Merge branch 'lt/deepen-builtin-source'

* lt/deepen-builtin-source:
  Move 'builtin-*' into a 'builtin/' subdirectory

Conflicts:
	Makefile

89 files changed, 42006 insertions, 0 deletions

diff --git a/builtin/add.c b/builtin/add.c
new file mode 100644
index 0000000..2705f8d
--- /dev/null
+++ b/builtin/add.c
@@ -0,0 +1,442 @@
+/*
+ * "git add" builtin command
+ *
+ * Copyright (C) 2006 Linus Torvalds
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "dir.h"
+#include "exec_cmd.h"
+#include "cache-tree.h"
+#include "run-command.h"
+#include "parse-options.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "revision.h"
+
+static const char * const builtin_add_usage[] = {
+	"git add [options] [--] <filepattern>...",
+	NULL
+};
+static int patch_interactive, add_interactive, edit_interactive;
+static int take_worktree_changes;
+
+struct update_callback_data
+{
+	int flags;
+	int add_errors;
+};
+
+static void update_callback(struct diff_queue_struct *q,
+			    struct diff_options *opt, void *cbdata)
+{
+	int i;
+	struct update_callback_data *data = cbdata;
+
+	for (i = 0; i < q->nr; i++) {
+		struct diff_filepair *p = q->queue[i];
+		const char *path = p->one->path;
+		switch (p->status) {
+		default:
+			die("unexpected diff status %c", p->status);
+		case DIFF_STATUS_UNMERGED:
+			/*
+			 * ADD_CACHE_IGNORE_REMOVAL is unset if "git
+			 * add -u" is calling us, In such a case, a
+			 * missing work tree file needs to be removed
+			 * if there is an unmerged entry at stage #2,
+			 * but such a diff record is followed by
+			 * another with DIFF_STATUS_DELETED (and if
+			 * there is no stage #2, we won't see DELETED
+			 * nor MODIFIED).  We can simply continue
+			 * either way.
+			 */
+			if (!(data->flags & ADD_CACHE_IGNORE_REMOVAL))
+				continue;
+			/*
+			 * Otherwise, it is "git add path" is asking
+			 * to explicitly add it; we fall through.  A
+			 * missing work tree file is an error and is
+			 * caught by add_file_to_index() in such a
+			 * case.
+			 */
+		case DIFF_STATUS_MODIFIED:
+		case DIFF_STATUS_TYPE_CHANGED:
+			if (add_file_to_index(&the_index, path, data->flags)) {
+				if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
+					die("updating files failed");
+				data->add_errors++;
+			}
+			break;
+		case DIFF_STATUS_DELETED:
+			if (data->flags & ADD_CACHE_IGNORE_REMOVAL)
+				break;
+			if (!(data->flags & ADD_CACHE_PRETEND))
+				remove_file_from_index(&the_index, path);
+			if (data->flags & (ADD_CACHE_PRETEND|ADD_CACHE_VERBOSE))
+				printf("remove '%s'\n", path);
+			break;
+		}
+	}
+}
+
+int add_files_to_cache(const char *prefix, const char **pathspec, int flags)
+{
+	struct update_callback_data data;
+	struct rev_info rev;
+	init_revisions(&rev, prefix);
+	setup_revisions(0, NULL, &rev, NULL);
+	rev.prune_data = pathspec;
+	rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
+	rev.diffopt.format_callback = update_callback;
+	data.flags = flags;
+	data.add_errors = 0;
+	rev.diffopt.format_callback_data = &data;
+	run_diff_files(&rev, DIFF_RACY_IS_MODIFIED);
+	return !!data.add_errors;
+}
+
+static void fill_pathspec_matches(const char **pathspec, char *seen, int specs)
+{
+	int num_unmatched = 0, i;
+
+	/*
+	 * Since we are walking the index as if we were walking the directory,
+	 * we have to mark the matched pathspec as seen; otherwise we will
+	 * mistakenly think that the user gave a pathspec that did not match
+	 * anything.
+	 */
+	for (i = 0; i < specs; i++)
+		if (!seen[i])
+			num_unmatched++;
+	if (!num_unmatched)
+		return;
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen);
+	}
+}
+
+static void prune_directory(struct dir_struct *dir, const char **pathspec, int prefix)
+{
+	char *seen;
+	int i, specs;
+	struct dir_entry **src, **dst;
+
+	for (specs = 0; pathspec[specs];  specs++)
+		/* nothing */;
+	seen = xcalloc(specs, 1);
+
+	src = dst = dir->entries;
+	i = dir->nr;
+	while (--i >= 0) {
+		struct dir_entry *entry = *src++;
+		if (match_pathspec(pathspec, entry->name, entry->len,
+				   prefix, seen))
+			*dst++ = entry;
+	}
+	dir->nr = dst - dir->entries;
+	fill_pathspec_matches(pathspec, seen, specs);
+
+	for (i = 0; i < specs; i++) {
+		if (!seen[i] && pathspec[i][0] && !file_exists(pathspec[i]))
+			die("pathspec '%s' did not match any files",
+					pathspec[i]);
+	}
+        free(seen);
+}
+
+static void treat_gitlinks(const char **pathspec)
+{
+	int i;
+
+	if (!pathspec || !*pathspec)
+		return;
+
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (S_ISGITLINK(ce->ce_mode)) {
+			int len = ce_namelen(ce), j;
+			for (j = 0; pathspec[j]; j++) {
+				int len2 = strlen(pathspec[j]);
+				if (len2 <= len || pathspec[j][len] != '/' ||
+				    memcmp(ce->name, pathspec[j], len))
+					continue;
+				if (len2 == len + 1)
+					/* strip trailing slash */
+					pathspec[j] = xstrndup(ce->name, len);
+				else
+					die ("Path '%s' is in submodule '%.*s'",
+						pathspec[j], len, ce->name);
+			}
+		}
+	}
+}
+
+static void refresh(int verbose, const char **pathspec)
+{
+	char *seen;
+	int i, specs;
+
+	for (specs = 0; pathspec[specs];  specs++)
+		/* nothing */;
+	seen = xcalloc(specs, 1);
+	refresh_index(&the_index, verbose ? REFRESH_IN_PORCELAIN : REFRESH_QUIET,
+		      pathspec, seen, "Unstaged changes after refreshing the index:");
+	for (i = 0; i < specs; i++) {
+		if (!seen[i])
+			die("pathspec '%s' did not match any files", pathspec[i]);
+	}
+        free(seen);
+}
+
+static const char **validate_pathspec(int argc, const char **argv, const char *prefix)
+{
+	const char **pathspec = get_pathspec(prefix, argv);
+
+	if (pathspec) {
+		const char **p;
+		for (p = pathspec; *p; p++) {
+			if (has_symlink_leading_path(*p, strlen(*p))) {
+				int len = prefix ? strlen(prefix) : 0;
+				die("'%s' is beyond a symbolic link", *p + len);
+			}
+		}
+	}
+
+	return pathspec;
+}
+
+int run_add_interactive(const char *revision, const char *patch_mode,
+			const char **pathspec)
+{
+	int status, ac, pc = 0;
+	const char **args;
+
+	if (pathspec)
+		while (pathspec[pc])
+			pc++;
+
+	args = xcalloc(sizeof(const char *), (pc + 5));
+	ac = 0;
+	args[ac++] = "add--interactive";
+	if (patch_mode)
+		args[ac++] = patch_mode;
+	if (revision)
+		args[ac++] = revision;
+	args[ac++] = "--";
+	if (pc) {
+		memcpy(&(args[ac]), pathspec, sizeof(const char *) * pc);
+		ac += pc;
+	}
+	args[ac] = NULL;
+
+	status = run_command_v_opt(args, RUN_GIT_CMD);
+	free(args);
+	return status;
+}
+
+int interactive_add(int argc, const char **argv, const char *prefix)
+{
+	const char **pathspec = NULL;
+
+	if (argc) {
+		pathspec = validate_pathspec(argc, argv, prefix);
+		if (!pathspec)
+			return -1;
+	}
+
+	return run_add_interactive(NULL,
+				   patch_interactive ? "--patch" : NULL,
+				   pathspec);
+}
+
+static int edit_patch(int argc, const char **argv, const char *prefix)
+{
+	char *file = xstrdup(git_path("ADD_EDIT.patch"));
+	const char *apply_argv[] = { "apply", "--recount", "--cached",
+		file, NULL };
+	struct child_process child;
+	struct rev_info rev;
+	int out;
+	struct stat st;
+
+	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
+
+	if (read_cache() < 0)
+		die ("Could not read the index");
+
+	init_revisions(&rev, prefix);
+	rev.diffopt.context = 7;
+
+	argc = setup_revisions(argc, argv, &rev, NULL);
+	rev.diffopt.output_format = DIFF_FORMAT_PATCH;
+	out = open(file, O_CREAT | O_WRONLY, 0644);
+	if (out < 0)
+		die ("Could not open '%s' for writing.", file);
+	rev.diffopt.file = xfdopen(out, "w");
+	rev.diffopt.close_file = 1;
+	if (run_diff_files(&rev, 0))
+		die ("Could not write patch");
+
+	launch_editor(file, NULL, NULL);
+
+	if (stat(file, &st))
+		die_errno("Could not stat '%s'", file);
+	if (!st.st_size)
+		die("Empty patch. Aborted.");
+
+	memset(&child, 0, sizeof(child));
+	child.git_cmd = 1;
+	child.argv = apply_argv;
+	if (run_command(&child))
+		die ("Could not apply '%s'", file);
+
+	unlink(file);
+	return 0;
+}
+
+static struct lock_file lock_file;
+
+static const char ignore_error[] =
+"The following paths are ignored by one of your .gitignore files:\n";
+
+static int verbose = 0, show_only = 0, ignored_too = 0, refresh_only = 0;
+static int ignore_add_errors, addremove, intent_to_add;
+
+static struct option builtin_add_options[] = {
+	OPT__DRY_RUN(&show_only),
+	OPT__VERBOSE(&verbose),
+	OPT_GROUP(""),
+	OPT_BOOLEAN('i', "interactive", &add_interactive, "interactive picking"),
+	OPT_BOOLEAN('p', "patch", &patch_interactive, "interactive patching"),
+	OPT_BOOLEAN('e', "edit", &edit_interactive, "edit current diff and apply"),
+	OPT_BOOLEAN('f', "force", &ignored_too, "allow adding otherwise ignored files"),
+	OPT_BOOLEAN('u', "update", &take_worktree_changes, "update tracked files"),
+	OPT_BOOLEAN('N', "intent-to-add", &intent_to_add, "record only the fact that the path will be added later"),
+	OPT_BOOLEAN('A', "all", &addremove, "add all, noticing removal of tracked files"),
+	OPT_BOOLEAN( 0 , "refresh", &refresh_only, "don't add, only refresh the index"),
+	OPT_BOOLEAN( 0 , "ignore-errors", &ignore_add_errors, "just skip files which cannot be added because of errors"),
+	OPT_END(),
+};
+
+static int add_config(const char *var, const char *value, void *cb)
+{
+	if (!strcasecmp(var, "add.ignore-errors")) {
+		ignore_add_errors = git_config_bool(var, value);
+		return 0;
+	}
+	return git_default_config(var, value, cb);
+}
+
+static int add_files(struct dir_struct *dir, int flags)
+{
+	int i, exit_status = 0;
+
+	if (dir->ignored_nr) {
+		fprintf(stderr, ignore_error);
+		for (i = 0; i < dir->ignored_nr; i++)
+			fprintf(stderr, "%s\n", dir->ignored[i]->name);
+		fprintf(stderr, "Use -f if you really want to add them.\n");
+		die("no files added");
+	}
+
+	for (i = 0; i < dir->nr; i++)
+		if (add_file_to_cache(dir->entries[i]->name, flags)) {
+			if (!ignore_add_errors)
+				die("adding files failed");
+			exit_status = 1;
+		}
+	return exit_status;
+}
+
+int cmd_add(int argc, const char **argv, const char *prefix)
+{
+	int exit_status = 0;
+	int newfd;
+	const char **pathspec;
+	struct dir_struct dir;
+	int flags;
+	int add_new_files;
+	int require_pathspec;
+
+	git_config(add_config, NULL);
+
+	argc = parse_options(argc, argv, prefix, builtin_add_options,
+			  builtin_add_usage, PARSE_OPT_KEEP_ARGV0);
+	if (patch_interactive)
+		add_interactive = 1;
+	if (add_interactive)
+		exit(interactive_add(argc - 1, argv + 1, prefix));
+
+	if (edit_interactive)
+		return(edit_patch(argc, argv, prefix));
+	argc--;
+	argv++;
+
+	if (addremove && take_worktree_changes)
+		die("-A and -u are mutually incompatible");
+	if ((addremove || take_worktree_changes) && !argc) {
+		static const char *here[2] = { ".", NULL };
+		argc = 1;
+		argv = here;
+	}
+
+	add_new_files = !take_worktree_changes && !refresh_only;
+	require_pathspec = !take_worktree_changes;
+
+	newfd = hold_locked_index(&lock_file, 1);
+
+	flags = ((verbose ? ADD_CACHE_VERBOSE : 0) |
+		 (show_only ? ADD_CACHE_PRETEND : 0) |
+		 (intent_to_add ? ADD_CACHE_INTENT : 0) |
+		 (ignore_add_errors ? ADD_CACHE_IGNORE_ERRORS : 0) |
+		 (!(addremove || take_worktree_changes)
+		  ? ADD_CACHE_IGNORE_REMOVAL : 0));
+
+	if (require_pathspec && argc == 0) {
+		fprintf(stderr, "Nothing specified, nothing added.\n");
+		fprintf(stderr, "Maybe you wanted to say 'git add .'?\n");
+		return 0;
+	}
+	pathspec = validate_pathspec(argc, argv, prefix);
+
+	if (read_cache() < 0)
+		die("index file corrupt");
+	treat_gitlinks(pathspec);
+
+	if (add_new_files) {
+		int baselen;
+
+		/* Set up the default git porcelain excludes */
+		memset(&dir, 0, sizeof(dir));
+		if (!ignored_too) {
+			dir.flags |= DIR_COLLECT_IGNORED;
+			setup_standard_excludes(&dir);
+		}
+
+		/* This picks up the paths that are not tracked */
+		baselen = fill_directory(&dir, pathspec);
+		if (pathspec)
+			prune_directory(&dir, pathspec, baselen);
+	}
+
+	if (refresh_only) {
+		refresh(verbose, pathspec);
+		goto finish;
+	}
+
+	exit_status |= add_files_to_cache(prefix, pathspec, flags);
+
+	if (add_new_files)
+		exit_status |= add_files(&dir, flags);
+
+ finish:
+	if (active_cache_changed) {
+		if (write_cache(newfd, active_cache, active_nr) ||
+		    commit_locked_index(&lock_file))
+			die("Unable to write new index file");
+	}
+
+	return exit_status;
+}
diff --git a/builtin/annotate.c b/builtin/annotate.c
new file mode 100644
index 0000000..fc43eed
--- /dev/null
+++ b/builtin/annotate.c
@@ -0,0 +1,24 @@
+/*
+ * "git annotate" builtin alias
+ *
+ * Copyright (C) 2006 Ryan Anderson
+ */
+#include "git-compat-util.h"
+#include "builtin.h"
+
+int cmd_annotate(int argc, const char **argv, const char *prefix)
+{
+	const char **nargv;
+	int i;
+	nargv = xmalloc(sizeof(char *) * (argc + 2));
+
+	nargv[0] = "annotate";
+	nargv[1] = "-c";
+
+	for (i = 1; i < argc; i++) {
+		nargv[i+1] = argv[i];
+	}
+	nargv[argc + 1] = NULL;
+
+	return cmd_blame(argc + 1, nargv, prefix);
+}
diff --git a/builtin/apply.c b/builtin/apply.c
new file mode 100644
index 0000000..3af4ae0
--- /dev/null
+++ b/builtin/apply.c
@@ -0,0 +1,3670 @@
+/*
+ * apply.c
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ *
+ * This applies patches on top of some (arbitrary) version of the SCM.
+ *
+ */
+#include "cache.h"
+#include "cache-tree.h"
+#include "quote.h"
+#include "blob.h"
+#include "delta.h"
+#include "builtin.h"
+#include "string-list.h"
+#include "dir.h"
+#include "parse-options.h"
+
+/*
+ *  --check turns on checking that the working tree matches the
+ *    files that are being modified, but doesn't apply the patch
+ *  --stat does just a diffstat, and doesn't actually apply
+ *  --numstat does numeric diffstat, and doesn't actually apply
+ *  --index-info shows the old and new index info for paths if available.
+ *  --index updates the cache as well.
+ *  --cached updates only the cache without ever touching the working tree.
+ */
+static const char *prefix;
+static int prefix_length = -1;
+static int newfd = -1;
+
+static int unidiff_zero;
+static int p_value = 1;
+static int p_value_known;
+static int check_index;
+static int update_index;
+static int cached;
+static int diffstat;
+static int numstat;
+static int summary;
+static int check;
+static int apply = 1;
+static int apply_in_reverse;
+static int apply_with_reject;
+static int apply_verbosely;
+static int no_add;
+static const char *fake_ancestor;
+static int line_termination = '\n';
+static unsigned int p_context = UINT_MAX;
+static const char * const apply_usage[] = {
+	"git apply [options] [<patch>...]",
+	NULL
+};
+
+static enum ws_error_action {
+	nowarn_ws_error,
+	warn_on_ws_error,
+	die_on_ws_error,
+	correct_ws_error,
+} ws_error_action = warn_on_ws_error;
+static int whitespace_error;
+static int squelch_whitespace_errors = 5;
+static int applied_after_fixing_ws;
+
+static enum ws_ignore {
+	ignore_ws_none,
+	ignore_ws_change,
+} ws_ignore_action = ignore_ws_none;
+
+
+static const char *patch_input_file;
+static const char *root;
+static int root_len;
+static int read_stdin = 1;
+static int options;
+
+static void parse_whitespace_option(const char *option)
+{
+	if (!option) {
+		ws_error_action = warn_on_ws_error;
+		return;
+	}
+	if (!strcmp(option, "warn")) {
+		ws_error_action = warn_on_ws_error;
+		return;
+	}
+	if (!strcmp(option, "nowarn")) {
+		ws_error_action = nowarn_ws_error;
+		return;
+	}
+	if (!strcmp(option, "error")) {
+		ws_error_action = die_on_ws_error;
+		return;
+	}
+	if (!strcmp(option, "error-all")) {
+		ws_error_action = die_on_ws_error;
+		squelch_whitespace_errors = 0;
+		return;
+	}
+	if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
+		ws_error_action = correct_ws_error;
+		return;
+	}
+	die("unrecognized whitespace option '%s'", option);
+}
+
+static void parse_ignorewhitespace_option(const char *option)
+{
+	if (!option || !strcmp(option, "no") ||
+	    !strcmp(option, "false") || !strcmp(option, "never") ||
+	    !strcmp(option, "none")) {
+		ws_ignore_action = ignore_ws_none;
+		return;
+	}
+	if (!strcmp(option, "change")) {
+		ws_ignore_action = ignore_ws_change;
+		return;
+	}
+	die("unrecognized whitespace ignore option '%s'", option);
+}
+
+static void set_default_whitespace_mode(const char *whitespace_option)
+{
+	if (!whitespace_option && !apply_default_whitespace)
+		ws_error_action = (apply ? warn_on_ws_error : nowarn_ws_error);
+}
+
+/*
+ * For "diff-stat" like behaviour, we keep track of the biggest change
+ * we've seen, and the longest filename. That allows us to do simple
+ * scaling.
+ */
+static int max_change, max_len;
+
+/*
+ * Various "current state", notably line numbers and what
+ * file (and how) we're patching right now.. The "is_xxxx"
+ * things are flags, where -1 means "don't know yet".
+ */
+static int linenr = 1;
+
+/*
+ * This represents one "hunk" from a patch, starting with
+ * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
+ * patch text is pointed at by patch, and its byte length
+ * is stored in size.  leading and trailing are the number
+ * of context lines.
+ */
+struct fragment {
+	unsigned long leading, trailing;
+	unsigned long oldpos, oldlines;
+	unsigned long newpos, newlines;
+	const char *patch;
+	int size;
+	int rejected;
+	int linenr;
+	struct fragment *next;
+};
+
+/*
+ * When dealing with a binary patch, we reuse "leading" field
+ * to store the type of the binary hunk, either deflated "delta"
+ * or deflated "literal".
+ */
+#define binary_patch_method leading
+#define BINARY_DELTA_DEFLATED	1
+#define BINARY_LITERAL_DEFLATED 2
+
+/*
+ * This represents a "patch" to a file, both metainfo changes
+ * such as creation/deletion, filemode and content changes represented
+ * as a series of fragments.
+ */
+struct patch {
+	char *new_name, *old_name, *def_name;
+	unsigned int old_mode, new_mode;
+	int is_new, is_delete;	/* -1 = unknown, 0 = false, 1 = true */
+	int rejected;
+	unsigned ws_rule;
+	unsigned long deflate_origlen;
+	int lines_added, lines_deleted;
+	int score;
+	unsigned int is_toplevel_relative:1;
+	unsigned int inaccurate_eof:1;
+	unsigned int is_binary:1;
+	unsigned int is_copy:1;
+	unsigned int is_rename:1;
+	unsigned int recount:1;
+	struct fragment *fragments;
+	char *result;
+	size_t resultsize;
+	char old_sha1_prefix[41];
+	char new_sha1_prefix[41];
+	struct patch *next;
+};
+
+/*
+ * A line in a file, len-bytes long (includes the terminating LF,
+ * except for an incomplete line at the end if the file ends with
+ * one), and its contents hashes to 'hash'.
+ */
+struct line {
+	size_t len;
+	unsigned hash : 24;
+	unsigned flag : 8;
+#define LINE_COMMON     1
+};
+
+/*
+ * This represents a "file", which is an array of "lines".
+ */
+struct image {
+	char *buf;
+	size_t len;
+	size_t nr;
+	size_t alloc;
+	struct line *line_allocated;
+	struct line *line;
+};
+
+/*
+ * Records filenames that have been touched, in order to handle
+ * the case where more than one patches touch the same file.
+ */
+
+static struct string_list fn_table;
+
+static uint32_t hash_line(const char *cp, size_t len)
+{
+	size_t i;
+	uint32_t h;
+	for (i = 0, h = 0; i < len; i++) {
+		if (!isspace(cp[i])) {
+			h = h * 3 + (cp[i] & 0xff);
+		}
+	}
+	return h;
+}
+
+/*
+ * Compare lines s1 of length n1 and s2 of length n2, ignoring
+ * whitespace difference. Returns 1 if they match, 0 otherwise
+ */
+static int fuzzy_matchlines(const char *s1, size_t n1,
+			    const char *s2, size_t n2)
+{
+	const char *last1 = s1 + n1 - 1;
+	const char *last2 = s2 + n2 - 1;
+	int result = 0;
+
+	if (n1 < 0 || n2 < 0)
+		return 0;
+
+	/* ignore line endings */
+	while ((*last1 == '\r') || (*last1 == '\n'))
+		last1--;
+	while ((*last2 == '\r') || (*last2 == '\n'))
+		last2--;
+
+	/* skip leading whitespace */
+	while (isspace(*s1) && (s1 <= last1))
+		s1++;
+	while (isspace(*s2) && (s2 <= last2))
+		s2++;
+	/* early return if both lines are empty */
+	if ((s1 > last1) && (s2 > last2))
+		return 1;
+	while (!result) {
+		result = *s1++ - *s2++;
+		/*
+		 * Skip whitespace inside. We check for whitespace on
+		 * both buffers because we don't want "a b" to match
+		 * "ab"
+		 */
+		if (isspace(*s1) && isspace(*s2)) {
+			while (isspace(*s1) && s1 <= last1)
+				s1++;
+			while (isspace(*s2) && s2 <= last2)
+				s2++;
+		}
+		/*
+		 * If we reached the end on one side only,
+		 * lines don't match
+		 */
+		if (
+		    ((s2 > last2) && (s1 <= last1)) ||
+		    ((s1 > last1) && (s2 <= last2)))
+			return 0;
+		if ((s1 > last1) && (s2 > last2))
+			break;
+	}
+
+	return !result;
+}
+
+static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
+{
+	ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
+	img->line_allocated[img->nr].len = len;
+	img->line_allocated[img->nr].hash = hash_line(bol, len);
+	img->line_allocated[img->nr].flag = flag;
+	img->nr++;
+}
+
+static void prepare_image(struct image *image, char *buf, size_t len,
+			  int prepare_linetable)
+{
+	const char *cp, *ep;
+
+	memset(image, 0, sizeof(*image));
+	image->buf = buf;
+	image->len = len;
+
+	if (!prepare_linetable)
+		return;
+
+	ep = image->buf + image->len;
+	cp = image->buf;
+	while (cp < ep) {
+		const char *next;
+		for (next = cp; next < ep && *next != '\n'; next++)
+			;
+		if (next < ep)
+			next++;
+		add_line_info(image, cp, next - cp, 0);
+		cp = next;
+	}
+	image->line = image->line_allocated;
+}
+
+static void clear_image(struct image *image)
+{
+	free(image->buf);
+	image->buf = NULL;
+	image->len = 0;
+}
+
+static void say_patch_name(FILE *output, const char *pre,
+			   struct patch *patch, const char *post)
+{
+	fputs(pre, output);
+	if (patch->old_name && patch->new_name &&
+	    strcmp(patch->old_name, patch->new_name)) {
+		quote_c_style(patch->old_name, NULL, output, 0);
+		fputs(" => ", output);
+		quote_c_style(patch->new_name, NULL, output, 0);
+	} else {
+		const char *n = patch->new_name;
+		if (!n)
+			n = patch->old_name;
+		quote_c_style(n, NULL, output, 0);
+	}
+	fputs(post, output);
+}
+
+#define CHUNKSIZE (8192)
+#define SLOP (16)
+
+static void read_patch_file(struct strbuf *sb, int fd)
+{
+	if (strbuf_read(sb, fd, 0) < 0)
+		die_errno("git apply: failed to read");
+
+	/*
+	 * Make sure that we have some slop in the buffer
+	 * so that we can do speculative "memcmp" etc, and
+	 * see to it that it is NUL-filled.
+	 */
+	strbuf_grow(sb, SLOP);
+	memset(sb->buf + sb->len, 0, SLOP);
+}
+
+static unsigned long linelen(const char *buffer, unsigned long size)
+{
+	unsigned long len = 0;
+	while (size--) {
+		len++;
+		if (*buffer++ == '\n')
+			break;
+	}
+	return len;
+}
+
+static int is_dev_null(const char *str)
+{
+	return !memcmp("/dev/null", str, 9) && isspace(str[9]);
+}
+
+#define TERM_SPACE	1
+#define TERM_TAB	2
+
+static int name_terminate(const char *name, int namelen, int c, int terminate)
+{
+	if (c == ' ' && !(terminate & TERM_SPACE))
+		return 0;
+	if (c == '\t' && !(terminate & TERM_TAB))
+		return 0;
+
+	return 1;
+}
+
+/* remove double slashes to make --index work with such filenames */
+static char *squash_slash(char *name)
+{
+	int i = 0, j = 0;
+
+	if (!name)
+		return NULL;
+
+	while (name[i]) {
+		if ((name[j++] = name[i++]) == '/')
+			while (name[i] == '/')
+				i++;
+	}
+	name[j] = '\0';
+	return name;
+}
+
+static char *find_name(const char *line, char *def, int p_value, int terminate)
+{
+	int len;
+	const char *start = NULL;
+
+	if (p_value == 0)
+		start = line;
+
+	if (*line == '"') {
+		struct strbuf name = STRBUF_INIT;
+
+		/*
+		 * Proposed "new-style" GNU patch/diff format; see
+		 * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
+		 */
+		if (!unquote_c_style(&name, line, NULL)) {
+			char *cp;
+
+			for (cp = name.buf; p_value; p_value--) {
+				cp = strchr(cp, '/');
+				if (!cp)
+					break;
+				cp++;
+			}
+			if (cp) {
+				/* name can later be freed, so we need
+				 * to memmove, not just return cp
+				 */
+				strbuf_remove(&name, 0, cp - name.buf);
+				free(def);
+				if (root)
+					strbuf_insert(&name, 0, root, root_len);
+				return squash_slash(strbuf_detach(&name, NULL));
+			}
+		}
+		strbuf_release(&name);
+	}
+
+	for (;;) {
+		char c = *line;
+
+		if (isspace(c)) {
+			if (c == '\n')
+				break;
+			if (name_terminate(start, line-start, c, terminate))
+				break;
+		}
+		line++;
+		if (c == '/' && !--p_value)
+			start = line;
+	}
+	if (!start)
+		return squash_slash(def);
+	len = line - start;
+	if (!len)
+		return squash_slash(def);
+
+	/*
+	 * Generally we prefer the shorter name, especially
+	 * if the other one is just a variation of that with
+	 * something else tacked on to the end (ie "file.orig"
+	 * or "file~").
+	 */
+	if (def) {
+		int deflen = strlen(def);
+		if (deflen < len && !strncmp(start, def, deflen))
+			return squash_slash(def);
+		free(def);
+	}
+
+	if (root) {
+		char *ret = xmalloc(root_len + len + 1);
+		strcpy(ret, root);
+		memcpy(ret + root_len, start, len);
+		ret[root_len + len] = '\0';
+		return squash_slash(ret);
+	}
+
+	return squash_slash(xmemdupz(start, len));
+}
+
+static int count_slashes(const char *cp)
+{
+	int cnt = 0;
+	char ch;
+
+	while ((ch = *cp++))
+		if (ch == '/')
+			cnt++;
+	return cnt;
+}
+
+/*
+ * Given the string after "--- " or "+++ ", guess the appropriate
+ * p_value for the given patch.
+ */
+static int guess_p_value(const char *nameline)
+{
+	char *name, *cp;
+	int val = -1;
+
+	if (is_dev_null(nameline))
+		return -1;
+	name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
+	if (!name)
+		return -1;
+	cp = strchr(name, '/');
+	if (!cp)
+		val = 0;
+	else if (prefix) {
+		/*
+		 * Does it begin with "a/$our-prefix" and such?  Then this is
+		 * very likely to apply to our directory.
+		 */
+		if (!strncmp(name, prefix, prefix_length))
+			val = count_slashes(prefix);
+		else {
+			cp++;
+			if (!strncmp(cp, prefix, prefix_length))
+				val = count_slashes(prefix) + 1;
+		}
+	}
+	free(name);
+	return val;
+}
+
+/*
+ * Does the ---/+++ line has the POSIX timestamp after the last HT?
+ * GNU diff puts epoch there to signal a creation/deletion event.  Is
+ * this such a timestamp?
+ */
+static int has_epoch_timestamp(const char *nameline)
+{
+	/*
+	 * We are only interested in epoch timestamp; any non-zero
+	 * fraction cannot be one, hence "(\.0+)?" in the regexp below.
+	 * For the same reason, the date must be either 1969-12-31 or
+	 * 1970-01-01, and the seconds part must be "00".
+	 */
+	const char stamp_regexp[] =
+		"^(1969-12-31|1970-01-01)"
+		" "
+		"[0-2][0-9]:[0-5][0-9]:00(\\.0+)?"
+		" "
+		"([-+][0-2][0-9][0-5][0-9])\n";
+	const char *timestamp = NULL, *cp;
+	static regex_t *stamp;
+	regmatch_t m[10];
+	int zoneoffset;
+	int hourminute;
+	int status;
+
+	for (cp = nameline; *cp != '\n'; cp++) {
+		if (*cp == '\t')
+			timestamp = cp + 1;
+	}
+	if (!timestamp)
+		return 0;
+	if (!stamp) {
+		stamp = xmalloc(sizeof(*stamp));
+		if (regcomp(stamp, stamp_regexp, REG_EXTENDED)) {
+			warning("Cannot prepare timestamp regexp %s",
+				stamp_regexp);
+			return 0;
+		}
+	}
+
+	status = regexec(stamp, timestamp, ARRAY_SIZE(m), m, 0);
+	if (status) {
+		if (status != REG_NOMATCH)
+			warning("regexec returned %d for input: %s",
+				status, timestamp);
+		return 0;
+	}
+
+	zoneoffset = strtol(timestamp + m[3].rm_so + 1, NULL, 10);
+	zoneoffset = (zoneoffset / 100) * 60 + (zoneoffset % 100);
+	if (timestamp[m[3].rm_so] == '-')
+		zoneoffset = -zoneoffset;
+
+	/*
+	 * YYYY-MM-DD hh:mm:ss must be from either 1969-12-31
+	 * (west of GMT) or 1970-01-01 (east of GMT)
+	 */
+	if ((zoneoffset < 0 && memcmp(timestamp, "1969-12-31", 10)) ||
+	    (0 <= zoneoffset && memcmp(timestamp, "1970-01-01", 10)))
+		return 0;
+
+	hourminute = (strtol(timestamp + 11, NULL, 10) * 60 +
+		      strtol(timestamp + 14, NULL, 10) -
+		      zoneoffset);
+
+	return ((zoneoffset < 0 && hourminute == 1440) ||
+		(0 <= zoneoffset && !hourminute));
+}
+
+/*
+ * Get the name etc info from the ---/+++ lines of a traditional patch header
+ *
+ * FIXME! The end-of-filename heuristics are kind of screwy. For existing
+ * files, we can happily check the index for a match, but for creating a
+ * new file we should try to match whatever "patch" does. I have no idea.
+ */
+static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
+{
+	char *name;
+
+	first += 4;	/* skip "--- " */
+	second += 4;	/* skip "+++ " */
+	if (!p_value_known) {
+		int p, q;
+		p = guess_p_value(first);
+		q = guess_p_value(second);
+		if (p < 0) p = q;
+		if (0 <= p && p == q) {
+			p_value = p;
+			p_value_known = 1;
+		}
+	}
+	if (is_dev_null(first)) {
+		patch->is_new = 1;
+		patch->is_delete = 0;
+		name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
+		patch->new_name = name;
+	} else if (is_dev_null(second)) {
+		patch->is_new = 0;
+		patch->is_delete = 1;
+		name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
+		patch->old_name = name;
+	} else {
+		name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
+		name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
+		if (has_epoch_timestamp(first)) {
+			patch->is_new = 1;
+			patch->is_delete = 0;
+			patch->new_name = name;
+		} else if (has_epoch_timestamp(second)) {
+			patch->is_new = 0;
+			patch->is_delete = 1;
+			patch->old_name = name;
+		} else {
+			patch->old_name = patch->new_name = name;
+		}
+	}
+	if (!name)
+		die("unable to find filename in patch at line %d", linenr);
+}
+
+static int gitdiff_hdrend(const char *line, struct patch *patch)
+{
+	return -1;
+}
+
+/*
+ * We're anal about diff header consistency, to make
+ * sure that we don't end up having strange ambiguous
+ * patches floating around.
+ *
+ * As a result, gitdiff_{old|new}name() will check
+ * their names against any previous information, just
+ * to make sure..
+ */
+static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
+{
+	if (!orig_name && !isnull)
+		return find_name(line, NULL, p_value, TERM_TAB);
+
+	if (orig_name) {
+		int len;
+		const char *name;
+		char *another;
+		name = orig_name;
+		len = strlen(name);
+		if (isnull)
+			die("git apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
+		another = find_name(line, NULL, p_value, TERM_TAB);
+		if (!another || memcmp(another, name, len + 1))
+			die("git apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
+		free(another);
+		return orig_name;
+	}
+	else {
+		/* expect "/dev/null" */
+		if (memcmp("/dev/null", line, 9) || line[9] != '\n')
+			die("git apply: bad git-diff - expected /dev/null on line %d", linenr);
+		return NULL;
+	}
+}
+
+static int gitdiff_oldname(const char *line, struct patch *patch)
+{
+	patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
+	return 0;
+}
+
+static int gitdiff_newname(const char *line, struct patch *patch)
+{
+	patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
+	return 0;
+}
+
+static int gitdiff_oldmode(const char *line, struct patch *patch)
+{
+	patch->old_mode = strtoul(line, NULL, 8);
+	return 0;
+}
+
+static int gitdiff_newmode(const char *line, struct patch *patch)
+{
+	patch->new_mode = strtoul(line, NULL, 8);
+	return 0;
+}
+
+static int gitdiff_delete(const char *line, struct patch *patch)
+{
+	patch->is_delete = 1;
+	patch->old_name = patch->def_name;
+	return gitdiff_oldmode(line, patch);
+}
+
+static int gitdiff_newfile(const char *line, struct patch *patch)
+{
+	patch->is_new = 1;
+	patch->new_name = patch->def_name;
+	return gitdiff_newmode(line, patch);
+}
+
+static int gitdiff_copysrc(const char *line, struct patch *patch)
+{
+	patch->is_copy = 1;
+	patch->old_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_copydst(const char *line, struct patch *patch)
+{
+	patch->is_copy = 1;
+	patch->new_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_renamesrc(const char *line, struct patch *patch)
+{
+	patch->is_rename = 1;
+	patch->old_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_renamedst(const char *line, struct patch *patch)
+{
+	patch->is_rename = 1;
+	patch->new_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_similarity(const char *line, struct patch *patch)
+{
+	if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
+		patch->score = 0;
+	return 0;
+}
+
+static int gitdiff_dissimilarity(const char *line, struct patch *patch)
+{
+	if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
+		patch->score = 0;
+	return 0;
+}
+
+static int gitdiff_index(const char *line, struct patch *patch)
+{
+	/*
+	 * index line is N hexadecimal, "..", N hexadecimal,
+	 * and optional space with octal mode.
+	 */
+	const char *ptr, *eol;
+	int len;
+
+	ptr = strchr(line, '.');
+	if (!ptr || ptr[1] != '.' || 40 < ptr - line)
+		return 0;
+	len = ptr - line;
+	memcpy(patch->old_sha1_prefix, line, len);
+	patch->old_sha1_prefix[len] = 0;
+
+	line = ptr + 2;
+	ptr = strchr(line, ' ');
+	eol = strchr(line, '\n');
+
+	if (!ptr || eol < ptr)
+		ptr = eol;
+	len = ptr - line;
+
+	if (40 < len)
+		return 0;
+	memcpy(patch->new_sha1_prefix, line, len);
+	patch->new_sha1_prefix[len] = 0;
+	if (*ptr == ' ')
+		patch->old_mode = strtoul(ptr+1, NULL, 8);
+	return 0;
+}
+
+/*
+ * This is normal for a diff that doesn't change anything: we'll fall through
+ * into the next diff. Tell the parser to break out.
+ */
+static int gitdiff_unrecognized(const char *line, struct patch *patch)
+{
+	return -1;
+}
+
+static const char *stop_at_slash(const char *line, int llen)
+{
+	int nslash = p_value;
+	int i;
+
+	for (i = 0; i < llen; i++) {
+		int ch = line[i];
+		if (ch == '/' && --nslash <= 0)
+			return &line[i];
+	}
+	return NULL;
+}
+
+/*
+ * This is to extract the same name that appears on "diff --git"
+ * line.  We do not find and return anything if it is a rename
+ * patch, and it is OK because we will find the name elsewhere.
+ * We need to reliably find name only when it is mode-change only,
+ * creation or deletion of an empty file.  In any of these cases,
+ * both sides are the same name under a/ and b/ respectively.
+ */
+static char *git_header_name(char *line, int llen)
+{
+	const char *name;
+	const char *second = NULL;
+	size_t len;
+
+	line += strlen("diff --git ");
+	llen -= strlen("diff --git ");
+
+	if (*line == '"') {
+		const char *cp;
+		struct strbuf first = STRBUF_INIT;
+		struct strbuf sp = STRBUF_INIT;
+
+		if (unquote_c_style(&first, line, &second))
+			goto free_and_fail1;
+
+		/* advance to the first slash */
+		cp = stop_at_slash(first.buf, first.len);
+		/* we do not accept absolute paths */
+		if (!cp || cp == first.buf)
+			goto free_and_fail1;
+		strbuf_remove(&first, 0, cp + 1 - first.buf);
+
+		/*
+		 * second points at one past closing dq of name.
+		 * find the second name.
+		 */
+		while ((second < line + llen) && isspace(*second))
+			second++;
+
+		if (line + llen <= second)
+			goto free_and_fail1;
+		if (*second == '"') {
+			if (unquote_c_style(&sp, second, NULL))
+				goto free_and_fail1;
+			cp = stop_at_slash(sp.buf, sp.len);
+			if (!cp || cp == sp.buf)
+				goto free_and_fail1;
+			/* They must match, otherwise ignore */
+			if (strcmp(cp + 1, first.buf))
+				goto free_and_fail1;
+			strbuf_release(&sp);
+			return strbuf_detach(&first, NULL);
+		}
+
+		/* unquoted second */
+		cp = stop_at_slash(second, line + llen - second);
+		if (!cp || cp == second)
+			goto free_and_fail1;
+		cp++;
+		if (line + llen - cp != first.len + 1 ||
+		    memcmp(first.buf, cp, first.len))
+			goto free_and_fail1;
+		return strbuf_detach(&first, NULL);
+
+	free_and_fail1:
+		strbuf_release(&first);
+		strbuf_release(&sp);
+		return NULL;
+	}
+
+	/* unquoted first name */
+	name = stop_at_slash(line, llen);
+	if (!name || name == line)
+		return NULL;
+	name++;
+
+	/*
+	 * since the first name is unquoted, a dq if exists must be
+	 * the beginning of the second name.
+	 */
+	for (second = name; second < line + llen; second++) {
+		if (*second == '"') {
+			struct strbuf sp = STRBUF_INIT;
+			const char *np;
+
+			if (unquote_c_style(&sp, second, NULL))
+				goto free_and_fail2;
+
+			np = stop_at_slash(sp.buf, sp.len);
+			if (!np || np == sp.buf)
+				goto free_and_fail2;
+			np++;
+
+			len = sp.buf + sp.len - np;
+			if (len < second - name &&
+			    !strncmp(np, name, len) &&
+			    isspace(name[len])) {
+				/* Good */
+				strbuf_remove(&sp, 0, np - sp.buf);
+				return strbuf_detach(&sp, NULL);
+			}
+
+		free_and_fail2:
+			strbuf_release(&sp);
+			return NULL;
+		}
+	}
+
+	/*
+	 * Accept a name only if it shows up twice, exactly the same
+	 * form.
+	 */
+	for (len = 0 ; ; len++) {
+		switch (name[len]) {
+		default:
+			continue;
+		case '\n':
+			return NULL;
+		case '\t': case ' ':
+			second = name+len;
+			for (;;) {
+				char c = *second++;
+				if (c == '\n')
+					return NULL;
+				if (c == '/')
+					break;
+			}
+			if (second[len] == '\n' && !memcmp(name, second, len)) {
+				return xmemdupz(name, len);
+			}
+		}
+	}
+}
+
+/* Verify that we recognize the lines following a git header */
+static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
+{
+	unsigned long offset;
+
+	/* A git diff has explicit new/delete information, so we don't guess */
+	patch->is_new = 0;
+	patch->is_delete = 0;
+
+	/*
+	 * Some things may not have the old name in the
+	 * rest of the headers anywhere (pure mode changes,
+	 * or removing or adding empty files), so we get
+	 * the default name from the header.
+	 */
+	patch->def_name = git_header_name(line, len);
+	if (patch->def_name && root) {
+		char *s = xmalloc(root_len + strlen(patch->def_name) + 1);
+		strcpy(s, root);
+		strcpy(s + root_len, patch->def_name);
+		free(patch->def_name);
+		patch->def_name = s;
+	}
+
+	line += len;
+	size -= len;
+	linenr++;
+	for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
+		static const struct opentry {
+			const char *str;
+			int (*fn)(const char *, struct patch *);
+		} optable[] = {
+			{ "@@ -", gitdiff_hdrend },
+			{ "--- ", gitdiff_oldname },
+			{ "+++ ", gitdiff_newname },
+			{ "old mode ", gitdiff_oldmode },
+			{ "new mode ", gitdiff_newmode },
+			{ "deleted file mode ", gitdiff_delete },
+			{ "new file mode ", gitdiff_newfile },
+			{ "copy from ", gitdiff_copysrc },
+			{ "copy to ", gitdiff_copydst },
+			{ "rename old ", gitdiff_renamesrc },
+			{ "rename new ", gitdiff_renamedst },
+			{ "rename from ", gitdiff_renamesrc },
+			{ "rename to ", gitdiff_renamedst },
+			{ "similarity index ", gitdiff_similarity },
+			{ "dissimilarity index ", gitdiff_dissimilarity },
+			{ "index ", gitdiff_index },
+			{ "", gitdiff_unrecognized },
+		};
+		int i;
+
+		len = linelen(line, size);
+		if (!len || line[len-1] != '\n')
+			break;
+		for (i = 0; i < ARRAY_SIZE(optable); i++) {
+			const struct opentry *p = optable + i;
+			int oplen = strlen(p->str);
+			if (len < oplen || memcmp(p->str, line, oplen))
+				continue;
+			if (p->fn(line + oplen, patch) < 0)
+				return offset;
+			break;
+		}
+	}
+
+	return offset;
+}
+
+static int parse_num(const char *line, unsigned long *p)
+{
+	char *ptr;
+
+	if (!isdigit(*line))
+		return 0;
+	*p = strtoul(line, &ptr, 10);
+	return ptr - line;
+}
+
+static int parse_range(const char *line, int len, int offset, const char *expect,
+		       unsigned long *p1, unsigned long *p2)
+{
+	int digits, ex;
+
+	if (offset < 0 || offset >= len)
+		return -1;
+	line += offset;
+	len -= offset;
+
+	digits = parse_num(line, p1);
+	if (!digits)
+		return -1;
+
+	offset += digits;
+	line += digits;
+	len -= digits;
+
+	*p2 = 1;
+	if (*line == ',') {
+		digits = parse_num(line+1, p2);
+		if (!digits)
+			return -1;
+
+		offset += digits+1;
+		line += digits+1;
+		len -= digits+1;
+	}
+
+	ex = strlen(expect);
+	if (ex > len)
+		return -1;
+	if (memcmp(line, expect, ex))
+		return -1;
+
+	return offset + ex;
+}
+
+static void recount_diff(char *line, int size, struct fragment *fragment)
+{
+	int oldlines = 0, newlines = 0, ret = 0;
+
+	if (size < 1) {
+		warning("recount: ignore empty hunk");
+		return;
+	}
+
+	for (;;) {
+		int len = linelen(line, size);
+		size -= len;
+		line += len;
+
+		if (size < 1)
+			break;
+
+		switch (*line) {
+		case ' ': case '\n':
+			newlines++;
+			/* fall through */
+		case '-':
+			oldlines++;
+			continue;
+		case '+':
+			newlines++;
+			continue;
+		case '\\':
+			continue;
+		case '@':
+			ret = size < 3 || prefixcmp(line, "@@ ");
+			break;
+		case 'd':
+			ret = size < 5 || prefixcmp(line, "diff ");
+			break;
+		default:
+			ret = -1;
+			break;
+		}
+		if (ret) {
+			warning("recount: unexpected line: %.*s",
+				(int)linelen(line, size), line);
+			return;
+		}
+		break;
+	}
+	fragment->oldlines = oldlines;
+	fragment->newlines = newlines;
+}
+
+/*
+ * Parse a unified diff fragment header of the
+ * form "@@ -a,b +c,d @@"
+ */
+static int parse_fragment_header(char *line, int len, struct fragment *fragment)
+{
+	int offset;
+
+	if (!len || line[len-1] != '\n')
+		return -1;
+
+	/* Figure out the number of lines in a fragment */
+	offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
+	offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
+
+	return offset;
+}
+
+static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
+{
+	unsigned long offset, len;
+
+	patch->is_toplevel_relative = 0;
+	patch->is_rename = patch->is_copy = 0;
+	patch->is_new = patch->is_delete = -1;
+	patch->old_mode = patch->new_mode = 0;
+	patch->old_name = patch->new_name = NULL;
+	for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
+		unsigned long nextlen;
+
+		len = linelen(line, size);
+		if (!len)
+			break;
+
+		/* Testing this early allows us to take a few shortcuts.. */
+		if (len < 6)
+			continue;
+
+		/*
+		 * Make sure we don't find any unconnected patch fragments.
+		 * That's a sign that we didn't find a header, and that a
+		 * patch has become corrupted/broken up.
+		 */
+		if (!memcmp("@@ -", line, 4)) {
+			struct fragment dummy;
+			if (parse_fragment_header(line, len, &dummy) < 0)
+				continue;
+			die("patch fragment without header at line %d: %.*s",
+			    linenr, (int)len-1, line);
+		}
+
+		if (size < len + 6)
+			break;
+
+		/*
+		 * Git patch? It might not have a real patch, just a rename
+		 * or mode change, so we handle that specially
+		 */
+		if (!memcmp("diff --git ", line, 11)) {
+			int git_hdr_len = parse_git_header(line, len, size, patch);
+			if (git_hdr_len <= len)
+				continue;
+			if (!patch->old_name && !patch->new_name) {
+				if (!patch->def_name)
+					die("git diff header lacks filename information when removing "
+					    "%d leading pathname components (line %d)" , p_value, linenr);
+				patch->old_name = patch->new_name = patch->def_name;
+			}
+			patch->is_toplevel_relative = 1;
+			*hdrsize = git_hdr_len;
+			return offset;
+		}
+
+		/* --- followed by +++ ? */
+		if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
+			continue;
+
+		/*
+		 * We only accept unified patches, so we want it to
+		 * at least have "@@ -a,b +c,d @@\n", which is 14 chars
+		 * minimum ("@@ -0,0 +1 @@\n" is the shortest).
+		 */
+		nextlen = linelen(line + len, size - len);
+		if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
+			continue;
+
+		/* Ok, we'll consider it a patch */
+		parse_traditional_patch(line, line+len, patch);
+		*hdrsize = len + nextlen;
+		linenr += 2;
+		return offset;
+	}
+	return -1;
+}
+
+static void record_ws_error(unsigned result, const char *line, int len, int linenr)
+{
+	char *err;
+
+	if (!result)
+		return;
+
+	whitespace_error++;
+	if (squelch_whitespace_errors &&
+	    squelch_whitespace_errors < whitespace_error)
+		return;
+
+	err = whitespace_error_string(result);
+	fprintf(stderr, "%s:%d: %s.\n%.*s\n",
+		patch_input_file, linenr, err, len, line);
+	free(err);
+}
+
+static void check_whitespace(const char *line, int len, unsigned ws_rule)
+{
+	unsigned result = ws_check(line + 1, len - 1, ws_rule);
+
+	record_ws_error(result, line + 1, len - 2, linenr);
+}
+
+/*
+ * Parse a unified diff. Note that this really needs to parse each
+ * fragment separately, since the only way to know the difference
+ * between a "---" that is part of a patch, and a "---" that starts
+ * the next patch is to look at the line counts..
+ */
+static int parse_fragment(char *line, unsigned long size,
+			  struct patch *patch, struct fragment *fragment)
+{
+	int added, deleted;
+	int len = linelen(line, size), offset;
+	unsigned long oldlines, newlines;
+	unsigned long leading, trailing;
+
+	offset = parse_fragment_header(line, len, fragment);
+	if (offset < 0)
+		return -1;
+	if (offset > 0 && patch->recount)
+		recount_diff(line + offset, size - offset, fragment);
+	oldlines = fragment->oldlines;
+	newlines = fragment->newlines;
+	leading = 0;
+	trailing = 0;
+
+	/* Parse the thing.. */
+	line += len;
+	size -= len;
+	linenr++;
+	added = deleted = 0;
+	for (offset = len;
+	     0 < size;
+	     offset += len, size -= len, line += len, linenr++) {
+		if (!oldlines && !newlines)
+			break;
+		len = linelen(line, size);
+		if (!len || line[len-1] != '\n')
+			return -1;
+		switch (*line) {
+		default:
+			return -1;
+		case '\n': /* newer GNU diff, an empty context line */
+		case ' ':
+			oldlines--;
+			newlines--;
+			if (!deleted && !added)
+				leading++;
+			trailing++;
+			break;
+		case '-':
+			if (apply_in_reverse &&
+			    ws_error_action != nowarn_ws_error)
+				check_whitespace(line, len, patch->ws_rule);
+			deleted++;
+			oldlines--;
+			trailing = 0;
+			break;
+		case '+':
+			if (!apply_in_reverse &&
+			    ws_error_action != nowarn_ws_error)
+				check_whitespace(line, len, patch->ws_rule);
+			added++;
+			newlines--;
+			trailing = 0;
+			break;
+
+		/*
+		 * We allow "\ No newline at end of file". Depending
+                 * on locale settings when the patch was produced we
+                 * don't know what this line looks like. The only
+                 * thing we do know is that it begins with "\ ".
+		 * Checking for 12 is just for sanity check -- any
+		 * l10n of "\ No newline..." is at least that long.
+		 */
+		case '\\':
+			if (len < 12 || memcmp(line, "\\ ", 2))
+				return -1;
+			break;
+		}
+	}
+	if (oldlines || newlines)
+		return -1;
+	fragment->leading = leading;
+	fragment->trailing = trailing;
+
+	/*
+	 * If a fragment ends with an incomplete line, we failed to include
+	 * it in the above loop because we hit oldlines == newlines == 0
+	 * before seeing it.
+	 */
+	if (12 < size && !memcmp(line, "\\ ", 2))
+		offset += linelen(line, size);
+
+	patch->lines_added += added;
+	patch->lines_deleted += deleted;
+
+	if (0 < patch->is_new && oldlines)
+		return error("new file depends on old contents");
+	if (0 < patch->is_delete && newlines)
+		return error("deleted file still has contents");
+	return offset;
+}
+
+static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
+{
+	unsigned long offset = 0;
+	unsigned long oldlines = 0, newlines = 0, context = 0;
+	struct fragment **fragp = &patch->fragments;
+
+	while (size > 4 && !memcmp(line, "@@ -", 4)) {
+		struct fragment *fragment;
+		int len;
+
+		fragment = xcalloc(1, sizeof(*fragment));
+		fragment->linenr = linenr;
+		len = parse_fragment(line, size, patch, fragment);
+		if (len <= 0)
+			die("corrupt patch at line %d", linenr);
+		fragment->patch = line;
+		fragment->size = len;
+		oldlines += fragment->oldlines;
+		newlines += fragment->newlines;
+		context += fragment->leading + fragment->trailing;
+
+		*fragp = fragment;
+		fragp = &fragment->next;
+
+		offset += len;
+		line += len;
+		size -= len;
+	}
+
+	/*
+	 * If something was removed (i.e. we have old-lines) it cannot
+	 * be creation, and if something was added it cannot be
+	 * deletion.  However, the reverse is not true; --unified=0
+	 * patches that only add are not necessarily creation even
+	 * though they do not have any old lines, and ones that only
+	 * delete are not necessarily deletion.
+	 *
+	 * Unfortunately, a real creation/deletion patch do _not_ have
+	 * any context line by definition, so we cannot safely tell it
+	 * apart with --unified=0 insanity.  At least if the patch has
+	 * more than one hunk it is not creation or deletion.
+	 */
+	if (patch->is_new < 0 &&
+	    (oldlines || (patch->fragments && patch->fragments->next)))
+		patch->is_new = 0;
+	if (patch->is_delete < 0 &&
+	    (newlines || (patch->fragments && patch->fragments->next)))
+		patch->is_delete = 0;
+
+	if (0 < patch->is_new && oldlines)
+		die("new file %s depends on old contents", patch->new_name);
+	if (0 < patch->is_delete && newlines)
+		die("deleted file %s still has contents", patch->old_name);
+	if (!patch->is_delete && !newlines && context)
+		fprintf(stderr, "** warning: file %s becomes empty but "
+			"is not deleted\n", patch->new_name);
+
+	return offset;
+}
+
+static inline int metadata_changes(struct patch *patch)
+{
+	return	patch->is_rename > 0 ||
+		patch->is_copy > 0 ||
+		patch->is_new > 0 ||
+		patch->is_delete ||
+		(patch->old_mode && patch->new_mode &&
+		 patch->old_mode != patch->new_mode);
+}
+
+static char *inflate_it(const void *data, unsigned long size,
+			unsigned long inflated_size)
+{
+	z_stream stream;
+	void *out;
+	int st;
+
+	memset(&stream, 0, sizeof(stream));
+
+	stream.next_in = (unsigned char *)data;
+	stream.avail_in = size;
+	stream.next_out = out = xmalloc(inflated_size);
+	stream.avail_out = inflated_size;
+	git_inflate_init(&stream);
+	st = git_inflate(&stream, Z_FINISH);
+	git_inflate_end(&stream);
+	if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
+		free(out);
+		return NULL;
+	}
+	return out;
+}
+
+static struct fragment *parse_binary_hunk(char **buf_p,
+					  unsigned long *sz_p,
+					  int *status_p,
+					  int *used_p)
+{
+	/*
+	 * Expect a line that begins with binary patch method ("literal"
+	 * or "delta"), followed by the length of data before deflating.
+	 * a sequence of 'length-byte' followed by base-85 encoded data
+	 * should follow, terminated by a newline.
+	 *
+	 * Each 5-byte sequence of base-85 encodes up to 4 bytes,
+	 * and we would limit the patch line to 66 characters,
+	 * so one line can fit up to 13 groups that would decode
+	 * to 52 bytes max.  The length byte 'A'-'Z' corresponds
+	 * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
+	 */
+	int llen, used;
+	unsigned long size = *sz_p;
+	char *buffer = *buf_p;
+	int patch_method;
+	unsigned long origlen;
+	char *data = NULL;
+	int hunk_size = 0;
+	struct fragment *frag;
+
+	llen = linelen(buffer, size);
+	used = llen;
+
+	*status_p = 0;
+
+	if (!prefixcmp(buffer, "delta ")) {
+		patch_method = BINARY_DELTA_DEFLATED;
+		origlen = strtoul(buffer + 6, NULL, 10);
+	}
+	else if (!prefixcmp(buffer, "literal ")) {
+		patch_method = BINARY_LITERAL_DEFLATED;
+		origlen = strtoul(buffer + 8, NULL, 10);
+	}
+	else
+		return NULL;
+
+	linenr++;
+	buffer += llen;
+	while (1) {
+		int byte_length, max_byte_length, newsize;
+		llen = linelen(buffer, size);
+		used += llen;
+		linenr++;
+		if (llen == 1) {
+			/* consume the blank line */
+			buffer++;
+			size--;
+			break;
+		}
+		/*
+		 * Minimum line is "A00000\n" which is 7-byte long,
+		 * and the line length must be multiple of 5 plus 2.
+		 */
+		if ((llen < 7) || (llen-2) % 5)
+			goto corrupt;
+		max_byte_length = (llen - 2) / 5 * 4;
+		byte_length = *buffer;
+		if ('A' <= byte_length && byte_length <= 'Z')
+			byte_length = byte_length - 'A' + 1;
+		else if ('a' <= byte_length && byte_length <= 'z')
+			byte_length = byte_length - 'a' + 27;
+		else
+			goto corrupt;
+		/* if the input length was not multiple of 4, we would
+		 * have filler at the end but the filler should never
+		 * exceed 3 bytes
+		 */
+		if (max_byte_length < byte_length ||
+		    byte_length <= max_byte_length - 4)
+			goto corrupt;
+		newsize = hunk_size + byte_length;
+		data = xrealloc(data, newsize);
+		if (decode_85(data + hunk_size, buffer + 1, byte_length))
+			goto corrupt;
+		hunk_size = newsize;
+		buffer += llen;
+		size -= llen;
+	}
+
+	frag = xcalloc(1, sizeof(*frag));
+	frag->patch = inflate_it(data, hunk_size, origlen);
+	if (!frag->patch)
+		goto corrupt;
+	free(data);
+	frag->size = origlen;
+	*buf_p = buffer;
+	*sz_p = size;
+	*used_p = used;
+	frag->binary_patch_method = patch_method;
+	return frag;
+
+ corrupt:
+	free(data);
+	*status_p = -1;
+	error("corrupt binary patch at line %d: %.*s",
+	      linenr-1, llen-1, buffer);
+	return NULL;
+}
+
+static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
+{
+	/*
+	 * We have read "GIT binary patch\n"; what follows is a line
+	 * that says the patch method (currently, either "literal" or
+	 * "delta") and the length of data before deflating; a
+	 * sequence of 'length-byte' followed by base-85 encoded data
+	 * follows.
+	 *
+	 * When a binary patch is reversible, there is another binary
+	 * hunk in the same format, starting with patch method (either
+	 * "literal" or "delta") with the length of data, and a sequence
+	 * of length-byte + base-85 encoded data, terminated with another
+	 * empty line.  This data, when applied to the postimage, produces
+	 * the preimage.
+	 */
+	struct fragment *forward;
+	struct fragment *reverse;
+	int status;
+	int used, used_1;
+
+	forward = parse_binary_hunk(&buffer, &size, &status, &used);
+	if (!forward && !status)
+		/* there has to be one hunk (forward hunk) */
+		return error("unrecognized binary patch at line %d", linenr-1);
+	if (status)
+		/* otherwise we already gave an error message */
+		return status;
+
+	reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
+	if (reverse)
+		used += used_1;
+	else if (status) {
+		/*
+		 * Not having reverse hunk is not an error, but having
+		 * a corrupt reverse hunk is.
+		 */
+		free((void*) forward->patch);
+		free(forward);
+		return status;
+	}
+	forward->next = reverse;
+	patch->fragments = forward;
+	patch->is_binary = 1;
+	return used;
+}
+
+static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
+{
+	int hdrsize, patchsize;
+	int offset = find_header(buffer, size, &hdrsize, patch);
+
+	if (offset < 0)
+		return offset;
+
+	patch->ws_rule = whitespace_rule(patch->new_name
+					 ? patch->new_name
+					 : patch->old_name);
+
+	patchsize = parse_single_patch(buffer + offset + hdrsize,
+				       size - offset - hdrsize, patch);
+
+	if (!patchsize) {
+		static const char *binhdr[] = {
+			"Binary files ",
+			"Files ",
+			NULL,
+		};
+		static const char git_binary[] = "GIT binary patch\n";
+		int i;
+		int hd = hdrsize + offset;
+		unsigned long llen = linelen(buffer + hd, size - hd);
+
+		if (llen == sizeof(git_binary) - 1 &&
+		    !memcmp(git_binary, buffer + hd, llen)) {
+			int used;
+			linenr++;
+			used = parse_binary(buffer + hd + llen,
+					    size - hd - llen, patch);
+			if (used)
+				patchsize = used + llen;
+			else
+				patchsize = 0;
+		}
+		else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
+			for (i = 0; binhdr[i]; i++) {
+				int len = strlen(binhdr[i]);
+				if (len < size - hd &&
+				    !memcmp(binhdr[i], buffer + hd, len)) {
+					linenr++;
+					patch->is_binary = 1;
+					patchsize = llen;
+					break;
+				}
+			}
+		}
+
+		/* Empty patch cannot be applied if it is a text patch
+		 * without metadata change.  A binary patch appears
+		 * empty to us here.
+		 */
+		if ((apply || check) &&
+		    (!patch->is_binary && !metadata_changes(patch)))
+			die("patch with only garbage at line %d", linenr);
+	}
+
+	return offset + hdrsize + patchsize;
+}
+
+#define swap(a,b) myswap((a),(b),sizeof(a))
+
+#define myswap(a, b, size) do {		\
+	unsigned char mytmp[size];	\
+	memcpy(mytmp, &a, size);		\
+	memcpy(&a, &b, size);		\
+	memcpy(&b, mytmp, size);		\
+} while (0)
+
+static void reverse_patches(struct patch *p)
+{
+	for (; p; p = p->next) {
+		struct fragment *frag = p->fragments;
+
+		swap(p->new_name, p->old_name);
+		swap(p->new_mode, p->old_mode);
+		swap(p->is_new, p->is_delete);
+		swap(p->lines_added, p->lines_deleted);
+		swap(p->old_sha1_prefix, p->new_sha1_prefix);
+
+		for (; frag; frag = frag->next) {
+			swap(frag->newpos, frag->oldpos);
+			swap(frag->newlines, frag->oldlines);
+		}
+	}
+}
+
+static const char pluses[] =
+"++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
+static const char minuses[]=
+"----------------------------------------------------------------------";
+
+static void show_stats(struct patch *patch)
+{
+	struct strbuf qname = STRBUF_INIT;
+	char *cp = patch->new_name ? patch->new_name : patch->old_name;
+	int max, add, del;
+
+	quote_c_style(cp, &qname, NULL, 0);
+
+	/*
+	 * "scale" the filename
+	 */
+	max = max_len;
+	if (max > 50)
+		max = 50;
+
+	if (qname.len > max) {
+		cp = strchr(qname.buf + qname.len + 3 - max, '/');
+		if (!cp)
+			cp = qname.buf + qname.len + 3 - max;
+		strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
+	}
+
+	if (patch->is_binary) {
+		printf(" %-*s |  Bin\n", max, qname.buf);
+		strbuf_release(&qname);
+		return;
+	}
+
+	printf(" %-*s |", max, qname.buf);
+	strbuf_release(&qname);
+
+	/*
+	 * scale the add/delete
+	 */
+	max = max + max_change > 70 ? 70 - max : max_change;
+	add = patch->lines_added;
+	del = patch->lines_deleted;
+
+	if (max_change > 0) {
+		int total = ((add + del) * max + max_change / 2) / max_change;
+		add = (add * max + max_change / 2) / max_change;
+		del = total - add;
+	}
+	printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
+		add, pluses, del, minuses);
+}
+
+static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
+{
+	switch (st->st_mode & S_IFMT) {
+	case S_IFLNK:
+		if (strbuf_readlink(buf, path, st->st_size) < 0)
+			return error("unable to read symlink %s", path);
+		return 0;
+	case S_IFREG:
+		if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
+			return error("unable to open or read %s", path);
+		convert_to_git(path, buf->buf, buf->len, buf, 0);
+		return 0;
+	default:
+		return -1;
+	}
+}
+
+/*
+ * Update the preimage, and the common lines in postimage,
+ * from buffer buf of length len. If postlen is 0 the postimage
+ * is updated in place, otherwise it's updated on a new buffer
+ * of length postlen
+ */
+
+static void update_pre_post_images(struct image *preimage,
+				   struct image *postimage,
+				   char *buf,
+				   size_t len, size_t postlen)
+{
+	int i, ctx;
+	char *new, *old, *fixed;
+	struct image fixed_preimage;
+
+	/*
+	 * Update the preimage with whitespace fixes.  Note that we
+	 * are not losing preimage->buf -- apply_one_fragment() will
+	 * free "oldlines".
+	 */
+	prepare_image(&fixed_preimage, buf, len, 1);
+	assert(fixed_preimage.nr == preimage->nr);
+	for (i = 0; i < preimage->nr; i++)
+		fixed_preimage.line[i].flag = preimage->line[i].flag;
+	free(preimage->line_allocated);
+	*preimage = fixed_preimage;
+
+	/*
+	 * Adjust the common context lines in postimage. This can be
+	 * done in-place when we are just doing whitespace fixing,
+	 * which does not make the string grow, but needs a new buffer
+	 * when ignoring whitespace causes the update, since in this case
+	 * we could have e.g. tabs converted to multiple spaces.
+	 * We trust the caller to tell us if the update can be done
+	 * in place (postlen==0) or not.
+	 */
+	old = postimage->buf;
+	if (postlen)
+		new = postimage->buf = xmalloc(postlen);
+	else
+		new = old;
+	fixed = preimage->buf;
+	for (i = ctx = 0; i < postimage->nr; i++) {
+		size_t len = postimage->line[i].len;
+		if (!(postimage->line[i].flag & LINE_COMMON)) {
+			/* an added line -- no counterparts in preimage */
+			memmove(new, old, len);
+			old += len;
+			new += len;
+			continue;
+		}
+
+		/* a common context -- skip it in the original postimage */
+		old += len;
+
+		/* and find the corresponding one in the fixed preimage */
+		while (ctx < preimage->nr &&
+		       !(preimage->line[ctx].flag & LINE_COMMON)) {
+			fixed += preimage->line[ctx].len;
+			ctx++;
+		}
+		if (preimage->nr <= ctx)
+			die("oops");
+
+		/* and copy it in, while fixing the line length */
+		len = preimage->line[ctx].len;
+		memcpy(new, fixed, len);
+		new += len;
+		fixed += len;
+		postimage->line[i].len = len;
+		ctx++;
+	}
+
+	/* Fix the length of the whole thing */
+	postimage->len = new - postimage->buf;
+}
+
+static int match_fragment(struct image *img,
+			  struct image *preimage,
+			  struct image *postimage,
+			  unsigned long try,
+			  int try_lno,
+			  unsigned ws_rule,
+			  int match_beginning, int match_end)
+{
+	int i;
+	char *fixed_buf, *buf, *orig, *target;
+
+	if (preimage->nr + try_lno > img->nr)
+		return 0;
+
+	if (match_beginning && try_lno)
+		return 0;
+
+	if (match_end && preimage->nr + try_lno != img->nr)
+		return 0;
+
+	/* Quick hash check */
+	for (i = 0; i < preimage->nr; i++)
+		if (preimage->line[i].hash != img->line[try_lno + i].hash)
+			return 0;
+
+	/*
+	 * Do we have an exact match?  If we were told to match
+	 * at the end, size must be exactly at try+fragsize,
+	 * otherwise try+fragsize must be still within the preimage,
+	 * and either case, the old piece should match the preimage
+	 * exactly.
+	 */
+	if ((match_end
+	     ? (try + preimage->len == img->len)
+	     : (try + preimage->len <= img->len)) &&
+	    !memcmp(img->buf + try, preimage->buf, preimage->len))
+		return 1;
+
+	/*
+	 * No exact match. If we are ignoring whitespace, run a line-by-line
+	 * fuzzy matching. We collect all the line length information because
+	 * we need it to adjust whitespace if we match.
+	 */
+	if (ws_ignore_action == ignore_ws_change) {
+		size_t imgoff = 0;
+		size_t preoff = 0;
+		size_t postlen = postimage->len;
+		for (i = 0; i < preimage->nr; i++) {
+			size_t prelen = preimage->line[i].len;
+			size_t imglen = img->line[try_lno+i].len;
+
+			if (!fuzzy_matchlines(img->buf + try + imgoff, imglen,
+					      preimage->buf + preoff, prelen))
+				return 0;
+			if (preimage->line[i].flag & LINE_COMMON)
+				postlen += imglen - prelen;
+			imgoff += imglen;
+			preoff += prelen;
+		}
+
+		/*
+		 * Ok, the preimage matches with whitespace fuzz. Update it and
+		 * the common postimage lines to use the same whitespace as the
+		 * target. imgoff now holds the true length of the target that
+		 * matches the preimage, and we need to update the line lengths
+		 * of the preimage to match the target ones.
+		 */
+		fixed_buf = xmalloc(imgoff);
+		memcpy(fixed_buf, img->buf + try, imgoff);
+		for (i = 0; i < preimage->nr; i++)
+			preimage->line[i].len = img->line[try_lno+i].len;
+
+		/*
+		 * Update the preimage buffer and the postimage context lines.
+		 */
+		update_pre_post_images(preimage, postimage,
+				fixed_buf, imgoff, postlen);
+		return 1;
+	}
+
+	if (ws_error_action != correct_ws_error)
+		return 0;
+
+	/*
+	 * The hunk does not apply byte-by-byte, but the hash says
+	 * it might with whitespace fuzz. We haven't been asked to
+	 * ignore whitespace, we were asked to correct whitespace
+	 * errors, so let's try matching after whitespace correction.
+	 */
+	fixed_buf = xmalloc(preimage->len + 1);
+	buf = fixed_buf;
+	orig = preimage->buf;
+	target = img->buf + try;
+	for (i = 0; i < preimage->nr; i++) {
+		size_t fixlen; /* length after fixing the preimage */
+		size_t oldlen = preimage->line[i].len;
+		size_t tgtlen = img->line[try_lno + i].len;
+		size_t tgtfixlen; /* length after fixing the target line */
+		char tgtfixbuf[1024], *tgtfix;
+		int match;
+
+		/* Try fixing the line in the preimage */
+		fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
+
+		/* Try fixing the line in the target */
+		if (sizeof(tgtfixbuf) > tgtlen)
+			tgtfix = tgtfixbuf;
+		else
+			tgtfix = xmalloc(tgtlen);
+		tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
+
+		/*
+		 * If they match, either the preimage was based on
+		 * a version before our tree fixed whitespace breakage,
+		 * or we are lacking a whitespace-fix patch the tree
+		 * the preimage was based on already had (i.e. target
+		 * has whitespace breakage, the preimage doesn't).
+		 * In either case, we are fixing the whitespace breakages
+		 * so we might as well take the fix together with their
+		 * real change.
+		 */
+		match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
+
+		if (tgtfix != tgtfixbuf)
+			free(tgtfix);
+		if (!match)
+			goto unmatch_exit;
+
+		orig += oldlen;
+		buf += fixlen;
+		target += tgtlen;
+	}
+
+	/*
+	 * Yes, the preimage is based on an older version that still
+	 * has whitespace breakages unfixed, and fixing them makes the
+	 * hunk match.  Update the context lines in the postimage.
+	 */
+	update_pre_post_images(preimage, postimage,
+			       fixed_buf, buf - fixed_buf, 0);
+	return 1;
+
+ unmatch_exit:
+	free(fixed_buf);
+	return 0;
+}
+
+static int find_pos(struct image *img,
+		    struct image *preimage,
+		    struct image *postimage,
+		    int line,
+		    unsigned ws_rule,
+		    int match_beginning, int match_end)
+{
+	int i;
+	unsigned long backwards, forwards, try;
+	int backwards_lno, forwards_lno, try_lno;
+
+	if (preimage->nr > img->nr)
+		return -1;
+
+	/*
+	 * If match_beginning or match_end is specified, there is no
+	 * point starting from a wrong line that will never match and
+	 * wander around and wait for a match at the specified end.
+	 */
+	if (match_beginning)
+		line = 0;
+	else if (match_end)
+		line = img->nr - preimage->nr;
+
+	if (line > img->nr)
+		line = img->nr;
+
+	try = 0;
+	for (i = 0; i < line; i++)
+		try += img->line[i].len;
+
+	/*
+	 * There's probably some smart way to do this, but I'll leave
+	 * that to the smart and beautiful people. I'm simple and stupid.
+	 */
+	backwards = try;
+	backwards_lno = line;
+	forwards = try;
+	forwards_lno = line;
+	try_lno = line;
+
+	for (i = 0; ; i++) {
+		if (match_fragment(img, preimage, postimage,
+				   try, try_lno, ws_rule,
+				   match_beginning, match_end))
+			return try_lno;
+
+	again:
+		if (backwards_lno == 0 && forwards_lno == img->nr)
+			break;
+
+		if (i & 1) {
+			if (backwards_lno == 0) {
+				i++;
+				goto again;
+			}
+			backwards_lno--;
+			backwards -= img->line[backwards_lno].len;
+			try = backwards;
+			try_lno = backwards_lno;
+		} else {
+			if (forwards_lno == img->nr) {
+				i++;
+				goto again;
+			}
+			forwards += img->line[forwards_lno].len;
+			forwards_lno++;
+			try = forwards;
+			try_lno = forwards_lno;
+		}
+
+	}
+	return -1;
+}
+
+static void remove_first_line(struct image *img)
+{
+	img->buf += img->line[0].len;
+	img->len -= img->line[0].len;
+	img->line++;
+	img->nr--;
+}
+
+static void remove_last_line(struct image *img)
+{
+	img->len -= img->line[--img->nr].len;
+}
+
+static void update_image(struct image *img,
+			 int applied_pos,
+			 struct image *preimage,
+			 struct image *postimage)
+{
+	/*
+	 * remove the copy of preimage at offset in img
+	 * and replace it with postimage
+	 */
+	int i, nr;
+	size_t remove_count, insert_count, applied_at = 0;
+	char *result;
+
+	for (i = 0; i < applied_pos; i++)
+		applied_at += img->line[i].len;
+
+	remove_count = 0;
+	for (i = 0; i < preimage->nr; i++)
+		remove_count += img->line[applied_pos + i].len;
+	insert_count = postimage->len;
+
+	/* Adjust the contents */
+	result = xmalloc(img->len + insert_count - remove_count + 1);
+	memcpy(result, img->buf, applied_at);
+	memcpy(result + applied_at, postimage->buf, postimage->len);
+	memcpy(result + applied_at + postimage->len,
+	       img->buf + (applied_at + remove_count),
+	       img->len - (applied_at + remove_count));
+	free(img->buf);
+	img->buf = result;
+	img->len += insert_count - remove_count;
+	result[img->len] = '\0';
+
+	/* Adjust the line table */
+	nr = img->nr + postimage->nr - preimage->nr;
+	if (preimage->nr < postimage->nr) {
+		/*
+		 * NOTE: this knows that we never call remove_first_line()
+		 * on anything other than pre/post image.
+		 */
+		img->line = xrealloc(img->line, nr * sizeof(*img->line));
+		img->line_allocated = img->line;
+	}
+	if (preimage->nr != postimage->nr)
+		memmove(img->line + applied_pos + postimage->nr,
+			img->line + applied_pos + preimage->nr,
+			(img->nr - (applied_pos + preimage->nr)) *
+			sizeof(*img->line));
+	memcpy(img->line + applied_pos,
+	       postimage->line,
+	       postimage->nr * sizeof(*img->line));
+	img->nr = nr;
+}
+
+static int apply_one_fragment(struct image *img, struct fragment *frag,
+			      int inaccurate_eof, unsigned ws_rule)
+{
+	int match_beginning, match_end;
+	const char *patch = frag->patch;
+	int size = frag->size;
+	char *old, *new, *oldlines, *newlines;
+	int new_blank_lines_at_end = 0;
+	unsigned long leading, trailing;
+	int pos, applied_pos;
+	struct image preimage;
+	struct image postimage;
+
+	memset(&preimage, 0, sizeof(preimage));
+	memset(&postimage, 0, sizeof(postimage));
+	oldlines = xmalloc(size);
+	newlines = xmalloc(size);
+
+	old = oldlines;
+	new = newlines;
+	while (size > 0) {
+		char first;
+		int len = linelen(patch, size);
+		int plen, added;
+		int added_blank_line = 0;
+		int is_blank_context = 0;
+
+		if (!len)
+			break;
+
+		/*
+		 * "plen" is how much of the line we should use for
+		 * the actual patch data. Normally we just remove the
+		 * first character on the line, but if the line is
+		 * followed by "\ No newline", then we also remove the
+		 * last one (which is the newline, of course).
+		 */
+		plen = len - 1;
+		if (len < size && patch[len] == '\\')
+			plen--;
+		first = *patch;
+		if (apply_in_reverse) {
+			if (first == '-')
+				first = '+';
+			else if (first == '+')
+				first = '-';
+		}
+
+		switch (first) {
+		case '\n':
+			/* Newer GNU diff, empty context line */
+			if (plen < 0)
+				/* ... followed by '\No newline'; nothing */
+				break;
+			*old++ = '\n';
+			*new++ = '\n';
+			add_line_info(&preimage, "\n", 1, LINE_COMMON);
+			add_line_info(&postimage, "\n", 1, LINE_COMMON);
+			is_blank_context = 1;
+			break;
+		case ' ':
+			if (plen && (ws_rule & WS_BLANK_AT_EOF) &&
+			    ws_blank_line(patch + 1, plen, ws_rule))
+				is_blank_context = 1;
+		case '-':
+			memcpy(old, patch + 1, plen);
+			add_line_info(&preimage, old, plen,
+				      (first == ' ' ? LINE_COMMON : 0));
+			old += plen;
+			if (first == '-')
+				break;
+		/* Fall-through for ' ' */
+		case '+':
+			/* --no-add does not add new lines */
+			if (first == '+' && no_add)
+				break;
+
+			if (first != '+' ||
+			    !whitespace_error ||
+			    ws_error_action != correct_ws_error) {
+				memcpy(new, patch + 1, plen);
+				added = plen;
+			}
+			else {
+				added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
+			}
+			add_line_info(&postimage, new, added,
+				      (first == '+' ? 0 : LINE_COMMON));
+			new += added;
+			if (first == '+' &&
+			    (ws_rule & WS_BLANK_AT_EOF) &&
+			    ws_blank_line(patch + 1, plen, ws_rule))
+				added_blank_line = 1;
+			break;
+		case '@': case '\\':
+			/* Ignore it, we already handled it */
+			break;
+		default:
+			if (apply_verbosely)
+				error("invalid start of line: '%c'", first);
+			return -1;
+		}
+		if (added_blank_line)
+			new_blank_lines_at_end++;
+		else if (is_blank_context)
+			;
+		else
+			new_blank_lines_at_end = 0;
+		patch += len;
+		size -= len;
+	}
+	if (inaccurate_eof &&
+	    old > oldlines && old[-1] == '\n' &&
+	    new > newlines && new[-1] == '\n') {
+		old--;
+		new--;
+	}
+
+	leading = frag->leading;
+	trailing = frag->trailing;
+
+	/*
+	 * A hunk to change lines at the beginning would begin with
+	 * @@ -1,L +N,M @@
+	 * but we need to be careful.  -U0 that inserts before the second
+	 * line also has this pattern.
+	 *
+	 * And a hunk to add to an empty file would begin with
+	 * @@ -0,0 +N,M @@
+	 *
+	 * In other words, a hunk that is (frag->oldpos <= 1) with or
+	 * without leading context must match at the beginning.
+	 */
+	match_beginning = (!frag->oldpos ||
+			   (frag->oldpos == 1 && !unidiff_zero));
+
+	/*
+	 * A hunk without trailing lines must match at the end.
+	 * However, we simply cannot tell if a hunk must match end
+	 * from the lack of trailing lines if the patch was generated
+	 * with unidiff without any context.
+	 */
+	match_end = !unidiff_zero && !trailing;
+
+	pos = frag->newpos ? (frag->newpos - 1) : 0;
+	preimage.buf = oldlines;
+	preimage.len = old - oldlines;
+	postimage.buf = newlines;
+	postimage.len = new - newlines;
+	preimage.line = preimage.line_allocated;
+	postimage.line = postimage.line_allocated;
+
+	for (;;) {
+
+		applied_pos = find_pos(img, &preimage, &postimage, pos,
+				       ws_rule, match_beginning, match_end);
+
+		if (applied_pos >= 0)
+			break;
+
+		/* Am I at my context limits? */
+		if ((leading <= p_context) && (trailing <= p_context))
+			break;
+		if (match_beginning || match_end) {
+			match_beginning = match_end = 0;
+			continue;
+		}
+
+		/*
+		 * Reduce the number of context lines; reduce both
+		 * leading and trailing if they are equal otherwise
+		 * just reduce the larger context.
+		 */
+		if (leading >= trailing) {
+			remove_first_line(&preimage);
+			remove_first_line(&postimage);
+			pos--;
+			leading--;
+		}
+		if (trailing > leading) {
+			remove_last_line(&preimage);
+			remove_last_line(&postimage);
+			trailing--;
+		}
+	}
+
+	if (applied_pos >= 0) {
+		if (new_blank_lines_at_end &&
+		    preimage.nr + applied_pos == img->nr &&
+		    (ws_rule & WS_BLANK_AT_EOF) &&
+		    ws_error_action != nowarn_ws_error) {
+			record_ws_error(WS_BLANK_AT_EOF, "+", 1, frag->linenr);
+			if (ws_error_action == correct_ws_error) {
+				while (new_blank_lines_at_end--)
+					remove_last_line(&postimage);
+			}
+			/*
+			 * We would want to prevent write_out_results()
+			 * from taking place in apply_patch() that follows
+			 * the callchain led us here, which is:
+			 * apply_patch->check_patch_list->check_patch->
+			 * apply_data->apply_fragments->apply_one_fragment
+			 */
+			if (ws_error_action == die_on_ws_error)
+				apply = 0;
+		}
+
+		/*
+		 * Warn if it was necessary to reduce the number
+		 * of context lines.
+		 */
+		if ((leading != frag->leading) ||
+		    (trailing != frag->trailing))
+			fprintf(stderr, "Context reduced to (%ld/%ld)"
+				" to apply fragment at %d\n",
+				leading, trailing, applied_pos+1);
+		update_image(img, applied_pos, &preimage, &postimage);
+	} else {
+		if (apply_verbosely)
+			error("while searching for:\n%.*s",
+			      (int)(old - oldlines), oldlines);
+	}
+
+	free(oldlines);
+	free(newlines);
+	free(preimage.line_allocated);
+	free(postimage.line_allocated);
+
+	return (applied_pos < 0);
+}
+
+static int apply_binary_fragment(struct image *img, struct patch *patch)
+{
+	struct fragment *fragment = patch->fragments;
+	unsigned long len;
+	void *dst;
+
+	/* Binary patch is irreversible without the optional second hunk */
+	if (apply_in_reverse) {
+		if (!fragment->next)
+			return error("cannot reverse-apply a binary patch "
+				     "without the reverse hunk to '%s'",
+				     patch->new_name
+				     ? patch->new_name : patch->old_name);
+		fragment = fragment->next;
+	}
+	switch (fragment->binary_patch_method) {
+	case BINARY_DELTA_DEFLATED:
+		dst = patch_delta(img->buf, img->len, fragment->patch,
+				  fragment->size, &len);
+		if (!dst)
+			return -1;
+		clear_image(img);
+		img->buf = dst;
+		img->len = len;
+		return 0;
+	case BINARY_LITERAL_DEFLATED:
+		clear_image(img);
+		img->len = fragment->size;
+		img->buf = xmalloc(img->len+1);
+		memcpy(img->buf, fragment->patch, img->len);
+		img->buf[img->len] = '\0';
+		return 0;
+	}
+	return -1;
+}
+
+static int apply_binary(struct image *img, struct patch *patch)
+{
+	const char *name = patch->old_name ? patch->old_name : patch->new_name;
+	unsigned char sha1[20];
+
+	/*
+	 * For safety, we require patch index line to contain
+	 * full 40-byte textual SHA1 for old and new, at least for now.
+	 */
+	if (strlen(patch->old_sha1_prefix) != 40 ||
+	    strlen(patch->new_sha1_prefix) != 40 ||
+	    get_sha1_hex(patch->old_sha1_prefix, sha1) ||
+	    get_sha1_hex(patch->new_sha1_prefix, sha1))
+		return error("cannot apply binary patch to '%s' "
+			     "without full index line", name);
+
+	if (patch->old_name) {
+		/*
+		 * See if the old one matches what the patch
+		 * applies to.
+		 */
+		hash_sha1_file(img->buf, img->len, blob_type, sha1);
+		if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
+			return error("the patch applies to '%s' (%s), "
+				     "which does not match the "
+				     "current contents.",
+				     name, sha1_to_hex(sha1));
+	}
+	else {
+		/* Otherwise, the old one must be empty. */
+		if (img->len)
+			return error("the patch applies to an empty "
+				     "'%s' but it is not empty", name);
+	}
+
+	get_sha1_hex(patch->new_sha1_prefix, sha1);
+	if (is_null_sha1(sha1)) {
+		clear_image(img);
+		return 0; /* deletion patch */
+	}
+
+	if (has_sha1_file(sha1)) {
+		/* We already have the postimage */
+		enum object_type type;
+		unsigned long size;
+		char *result;
+
+		result = read_sha1_file(sha1, &type, &size);
+		if (!result)
+			return error("the necessary postimage %s for "
+				     "'%s' cannot be read",
+				     patch->new_sha1_prefix, name);
+		clear_image(img);
+		img->buf = result;
+		img->len = size;
+	} else {
+		/*
+		 * We have verified buf matches the preimage;
+		 * apply the patch data to it, which is stored
+		 * in the patch->fragments->{patch,size}.
+		 */
+		if (apply_binary_fragment(img, patch))
+			return error("binary patch does not apply to '%s'",
+				     name);
+
+		/* verify that the result matches */
+		hash_sha1_file(img->buf, img->len, blob_type, sha1);
+		if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
+			return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
+				name, patch->new_sha1_prefix, sha1_to_hex(sha1));
+	}
+
+	return 0;
+}
+
+static int apply_fragments(struct image *img, struct patch *patch)
+{
+	struct fragment *frag = patch->fragments;
+	const char *name = patch->old_name ? patch->old_name : patch->new_name;
+	unsigned ws_rule = patch->ws_rule;
+	unsigned inaccurate_eof = patch->inaccurate_eof;
+
+	if (patch->is_binary)
+		return apply_binary(img, patch);
+
+	while (frag) {
+		if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
+			error("patch failed: %s:%ld", name, frag->oldpos);
+			if (!apply_with_reject)
+				return -1;
+			frag->rejected = 1;
+		}
+		frag = frag->next;
+	}
+	return 0;
+}
+
+static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
+{
+	if (!ce)
+		return 0;
+
+	if (S_ISGITLINK(ce->ce_mode)) {
+		strbuf_grow(buf, 100);
+		strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
+	} else {
+		enum object_type type;
+		unsigned long sz;
+		char *result;
+
+		result = read_sha1_file(ce->sha1, &type, &sz);
+		if (!result)
+			return -1;
+		/* XXX read_sha1_file NUL-terminates */
+		strbuf_attach(buf, result, sz, sz + 1);
+	}
+	return 0;
+}
+
+static struct patch *in_fn_table(const char *name)
+{
+	struct string_list_item *item;
+
+	if (name == NULL)
+		return NULL;
+
+	item = string_list_lookup(name, &fn_table);
+	if (item != NULL)
+		return (struct patch *)item->util;
+
+	return NULL;
+}
+
+/*
+ * item->util in the filename table records the status of the path.
+ * Usually it points at a patch (whose result records the contents
+ * of it after applying it), but it could be PATH_WAS_DELETED for a
+ * path that a previously applied patch has already removed.
+ */
+ #define PATH_TO_BE_DELETED ((struct patch *) -2)
+#define PATH_WAS_DELETED ((struct patch *) -1)
+
+static int to_be_deleted(struct patch *patch)
+{
+	return patch == PATH_TO_BE_DELETED;
+}
+
+static int was_deleted(struct patch *patch)
+{
+	return patch == PATH_WAS_DELETED;
+}
+
+static void add_to_fn_table(struct patch *patch)
+{
+	struct string_list_item *item;
+
+	/*
+	 * Always add new_name unless patch is a deletion
+	 * This should cover the cases for normal diffs,
+	 * file creations and copies
+	 */
+	if (patch->new_name != NULL) {
+		item = string_list_insert(patch->new_name, &fn_table);
+		item->util = patch;
+	}
+
+	/*
+	 * store a failure on rename/deletion cases because
+	 * later chunks shouldn't patch old names
+	 */
+	if ((patch->new_name == NULL) || (patch->is_rename)) {
+		item = string_list_insert(patch->old_name, &fn_table);
+		item->util = PATH_WAS_DELETED;
+	}
+}
+
+static void prepare_fn_table(struct patch *patch)
+{
+	/*
+	 * store information about incoming file deletion
+	 */
+	while (patch) {
+		if ((patch->new_name == NULL) || (patch->is_rename)) {
+			struct string_list_item *item;
+			item = string_list_insert(patch->old_name, &fn_table);
+			item->util = PATH_TO_BE_DELETED;
+		}
+		patch = patch->next;
+	}
+}
+
+static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
+{
+	struct strbuf buf = STRBUF_INIT;
+	struct image image;
+	size_t len;
+	char *img;
+	struct patch *tpatch;
+
+	if (!(patch->is_copy || patch->is_rename) &&
+	    (tpatch = in_fn_table(patch->old_name)) != NULL && !to_be_deleted(tpatch)) {
+		if (was_deleted(tpatch)) {
+			return error("patch %s has been renamed/deleted",
+				patch->old_name);
+		}
+		/* We have a patched copy in memory use that */
+		strbuf_add(&buf, tpatch->result, tpatch->resultsize);
+	} else if (cached) {
+		if (read_file_or_gitlink(ce, &buf))
+			return error("read of %s failed", patch->old_name);
+	} else if (patch->old_name) {
+		if (S_ISGITLINK(patch->old_mode)) {
+			if (ce) {
+				read_file_or_gitlink(ce, &buf);
+			} else {
+				/*
+				 * There is no way to apply subproject
+				 * patch without looking at the index.
+				 */
+				patch->fragments = NULL;
+			}
+		} else {
+			if (read_old_data(st, patch->old_name, &buf))
+				return error("read of %s failed", patch->old_name);
+		}
+	}
+
+	img = strbuf_detach(&buf, &len);
+	prepare_image(&image, img, len, !patch->is_binary);
+
+	if (apply_fragments(&image, patch) < 0)
+		return -1; /* note with --reject this succeeds. */
+	patch->result = image.buf;
+	patch->resultsize = image.len;
+	add_to_fn_table(patch);
+	free(image.line_allocated);
+
+	if (0 < patch->is_delete && patch->resultsize)
+		return error("removal patch leaves file contents");
+
+	return 0;
+}
+
+static int check_to_create_blob(const char *new_name, int ok_if_exists)
+{
+	struct stat nst;
+	if (!lstat(new_name, &nst)) {
+		if (S_ISDIR(nst.st_mode) || ok_if_exists)
+			return 0;
+		/*
+		 * A leading component of new_name might be a symlink
+		 * that is going to be removed with this patch, but
+		 * still pointing at somewhere that has the path.
+		 * In such a case, path "new_name" does not exist as
+		 * far as git is concerned.
+		 */
+		if (has_symlink_leading_path(new_name, strlen(new_name)))
+			return 0;
+
+		return error("%s: already exists in working directory", new_name);
+	}
+	else if ((errno != ENOENT) && (errno != ENOTDIR))
+		return error("%s: %s", new_name, strerror(errno));
+	return 0;
+}
+
+static int verify_index_match(struct cache_entry *ce, struct stat *st)
+{
+	if (S_ISGITLINK(ce->ce_mode)) {
+		if (!S_ISDIR(st->st_mode))
+			return -1;
+		return 0;
+	}
+	return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
+}
+
+static int check_preimage(struct patch *patch, struct cache_entry **ce, struct stat *st)
+{
+	const char *old_name = patch->old_name;
+	struct patch *tpatch = NULL;
+	int stat_ret = 0;
+	unsigned st_mode = 0;
+
+	/*
+	 * Make sure that we do not have local modifications from the
+	 * index when we are looking at the index.  Also make sure
+	 * we have the preimage file to be patched in the work tree,
+	 * unless --cached, which tells git to apply only in the index.
+	 */
+	if (!old_name)
+		return 0;
+
+	assert(patch->is_new <= 0);
+
+	if (!(patch->is_copy || patch->is_rename) &&
+	    (tpatch = in_fn_table(old_name)) != NULL && !to_be_deleted(tpatch)) {
+		if (was_deleted(tpatch))
+			return error("%s: has been deleted/renamed", old_name);
+		st_mode = tpatch->new_mode;
+	} else if (!cached) {
+		stat_ret = lstat(old_name, st);
+		if (stat_ret && errno != ENOENT)
+			return error("%s: %s", old_name, strerror(errno));
+	}
+
+	if (to_be_deleted(tpatch))
+		tpatch = NULL;
+
+	if (check_index && !tpatch) {
+		int pos = cache_name_pos(old_name, strlen(old_name));
+		if (pos < 0) {
+			if (patch->is_new < 0)
+				goto is_new;
+			return error("%s: does not exist in index", old_name);
+		}
+		*ce = active_cache[pos];
+		if (stat_ret < 0) {
+			struct checkout costate;
+			/* checkout */
+			costate.base_dir = "";
+			costate.base_dir_len = 0;
+			costate.force = 0;
+			costate.quiet = 0;
+			costate.not_new = 0;
+			costate.refresh_cache = 1;
+			if (checkout_entry(*ce, &costate, NULL) ||
+			    lstat(old_name, st))
+				return -1;
+		}
+		if (!cached && verify_index_match(*ce, st))
+			return error("%s: does not match index", old_name);
+		if (cached)
+			st_mode = (*ce)->ce_mode;
+	} else if (stat_ret < 0) {
+		if (patch->is_new < 0)
+			goto is_new;
+		return error("%s: %s", old_name, strerror(errno));
+	}
+
+	if (!cached && !tpatch)
+		st_mode = ce_mode_from_stat(*ce, st->st_mode);
+
+	if (patch->is_new < 0)
+		patch->is_new = 0;
+	if (!patch->old_mode)
+		patch->old_mode = st_mode;
+	if ((st_mode ^ patch->old_mode) & S_IFMT)
+		return error("%s: wrong type", old_name);
+	if (st_mode != patch->old_mode)
+		warning("%s has type %o, expected %o",
+			old_name, st_mode, patch->old_mode);
+	if (!patch->new_mode && !patch->is_delete)
+		patch->new_mode = st_mode;
+	return 0;
+
+ is_new:
+	patch->is_new = 1;
+	patch->is_delete = 0;
+	patch->old_name = NULL;
+	return 0;
+}
+
+static int check_patch(struct patch *patch)
+{
+	struct stat st;
+	const char *old_name = patch->old_name;
+	const char *new_name = patch->new_name;
+	const char *name = old_name ? old_name : new_name;
+	struct cache_entry *ce = NULL;
+	struct patch *tpatch;
+	int ok_if_exists;
+	int status;
+
+	patch->rejected = 1; /* we will drop this after we succeed */
+
+	status = check_preimage(patch, &ce, &st);
+	if (status)
+		return status;
+	old_name = patch->old_name;
+
+	if ((tpatch = in_fn_table(new_name)) &&
+			(was_deleted(tpatch) || to_be_deleted(tpatch)))
+		/*
+		 * A type-change diff is always split into a patch to
+		 * delete old, immediately followed by a patch to
+		 * create new (see diff.c::run_diff()); in such a case
+		 * it is Ok that the entry to be deleted by the
+		 * previous patch is still in the working tree and in
+		 * the index.
+		 */
+		ok_if_exists = 1;
+	else
+		ok_if_exists = 0;
+
+	if (new_name &&
+	    ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
+		if (check_index &&
+		    cache_name_pos(new_name, strlen(new_name)) >= 0 &&
+		    !ok_if_exists)
+			return error("%s: already exists in index", new_name);
+		if (!cached) {
+			int err = check_to_create_blob(new_name, ok_if_exists);
+			if (err)
+				return err;
+		}
+		if (!patch->new_mode) {
+			if (0 < patch->is_new)
+				patch->new_mode = S_IFREG | 0644;
+			else
+				patch->new_mode = patch->old_mode;
+		}
+	}
+
+	if (new_name && old_name) {
+		int same = !strcmp(old_name, new_name);
+		if (!patch->new_mode)
+			patch->new_mode = patch->old_mode;
+		if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
+			return error("new mode (%o) of %s does not match old mode (%o)%s%s",
+				patch->new_mode, new_name, patch->old_mode,
+				same ? "" : " of ", same ? "" : old_name);
+	}
+
+	if (apply_data(patch, &st, ce) < 0)
+		return error("%s: patch does not apply", name);
+	patch->rejected = 0;
+	return 0;
+}
+
+static int check_patch_list(struct patch *patch)
+{
+	int err = 0;
+
+	prepare_fn_table(patch);
+	while (patch) {
+		if (apply_verbosely)
+			say_patch_name(stderr,
+				       "Checking patch ", patch, "...\n");
+		err |= check_patch(patch);
+		patch = patch->next;
+	}
+	return err;
+}
+
+/* This function tries to read the sha1 from the current index */
+static int get_current_sha1(const char *path, unsigned char *sha1)
+{
+	int pos;
+
+	if (read_cache() < 0)
+		return -1;
+	pos = cache_name_pos(path, strlen(path));
+	if (pos < 0)
+		return -1;
+	hashcpy(sha1, active_cache[pos]->sha1);
+	return 0;
+}
+
+/* Build an index that contains the just the files needed for a 3way merge */
+static void build_fake_ancestor(struct patch *list, const char *filename)
+{
+	struct patch *patch;
+	struct index_state result = { NULL };
+	int fd;
+
+	/* Once we start supporting the reverse patch, it may be
+	 * worth showing the new sha1 prefix, but until then...
+	 */
+	for (patch = list; patch; patch = patch->next) {
+		const unsigned char *sha1_ptr;
+		unsigned char sha1[20];
+		struct cache_entry *ce;
+		const char *name;
+
+		name = patch->old_name ? patch->old_name : patch->new_name;
+		if (0 < patch->is_new)
+			continue;
+		else if (get_sha1(patch->old_sha1_prefix, sha1))
+			/* git diff has no index line for mode/type changes */
+			if (!patch->lines_added && !patch->lines_deleted) {
+				if (get_current_sha1(patch->new_name, sha1) ||
+				    get_current_sha1(patch->old_name, sha1))
+					die("mode change for %s, which is not "
+						"in current HEAD", name);
+				sha1_ptr = sha1;
+			} else
+				die("sha1 information is lacking or useless "
+					"(%s).", name);
+		else
+			sha1_ptr = sha1;
+
+		ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
+		if (!ce)
+			die("make_cache_entry failed for path '%s'", name);
+		if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
+			die ("Could not add %s to temporary index", name);
+	}
+
+	fd = open(filename, O_WRONLY | O_CREAT, 0666);
+	if (fd < 0 || write_index(&result, fd) || close(fd))
+		die ("Could not write temporary index to %s", filename);
+
+	discard_index(&result);
+}
+
+static void stat_patch_list(struct patch *patch)
+{
+	int files, adds, dels;
+
+	for (files = adds = dels = 0 ; patch ; patch = patch->next) {
+		files++;
+		adds += patch->lines_added;
+		dels += patch->lines_deleted;
+		show_stats(patch);
+	}
+
+	printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
+}
+
+static void numstat_patch_list(struct patch *patch)
+{
+	for ( ; patch; patch = patch->next) {
+		const char *name;
+		name = patch->new_name ? patch->new_name : patch->old_name;
+		if (patch->is_binary)
+			printf("-\t-\t");
+		else
+			printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
+		write_name_quoted(name, stdout, line_termination);
+	}
+}
+
+static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
+{
+	if (mode)
+		printf(" %s mode %06o %s\n", newdelete, mode, name);
+	else
+		printf(" %s %s\n", newdelete, name);
+}
+
+static void show_mode_change(struct patch *p, int show_name)
+{
+	if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
+		if (show_name)
+			printf(" mode change %06o => %06o %s\n",
+			       p->old_mode, p->new_mode, p->new_name);
+		else
+			printf(" mode change %06o => %06o\n",
+			       p->old_mode, p->new_mode);
+	}
+}
+
+static void show_rename_copy(struct patch *p)
+{
+	const char *renamecopy = p->is_rename ? "rename" : "copy";
+	const char *old, *new;
+
+	/* Find common prefix */
+	old = p->old_name;
+	new = p->new_name;
+	while (1) {
+		const char *slash_old, *slash_new;
+		slash_old = strchr(old, '/');
+		slash_new = strchr(new, '/');
+		if (!slash_old ||
+		    !slash_new ||
+		    slash_old - old != slash_new - new ||
+		    memcmp(old, new, slash_new - new))
+			break;
+		old = slash_old + 1;
+		new = slash_new + 1;
+	}
+	/* p->old_name thru old is the common prefix, and old and new
+	 * through the end of names are renames
+	 */
+	if (old != p->old_name)
+		printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
+		       (int)(old - p->old_name), p->old_name,
+		       old, new, p->score);
+	else
+		printf(" %s %s => %s (%d%%)\n", renamecopy,
+		       p->old_name, p->new_name, p->score);
+	show_mode_change(p, 0);
+}
+
+static void summary_patch_list(struct patch *patch)
+{
+	struct patch *p;
+
+	for (p = patch; p; p = p->next) {
+		if (p->is_new)
+			show_file_mode_name("create", p->new_mode, p->new_name);
+		else if (p->is_delete)
+			show_file_mode_name("delete", p->old_mode, p->old_name);
+		else {
+			if (p->is_rename || p->is_copy)
+				show_rename_copy(p);
+			else {
+				if (p->score) {
+					printf(" rewrite %s (%d%%)\n",
+					       p->new_name, p->score);
+					show_mode_change(p, 0);
+				}
+				else
+					show_mode_change(p, 1);
+			}
+		}
+	}
+}
+
+static void patch_stats(struct patch *patch)
+{
+	int lines = patch->lines_added + patch->lines_deleted;
+
+	if (lines > max_change)
+		max_change = lines;
+	if (patch->old_name) {
+		int len = quote_c_style(patch->old_name, NULL, NULL, 0);
+		if (!len)
+			len = strlen(patch->old_name);
+		if (len > max_len)
+			max_len = len;
+	}
+	if (patch->new_name) {
+		int len = quote_c_style(patch->new_name, NULL, NULL, 0);
+		if (!len)
+			len = strlen(patch->new_name);
+		if (len > max_len)
+			max_len = len;
+	}
+}
+
+static void remove_file(struct patch *patch, int rmdir_empty)
+{
+	if (update_index) {
+		if (remove_file_from_cache(patch->old_name) < 0)
+			die("unable to remove %s from index", patch->old_name);
+	}
+	if (!cached) {
+		if (S_ISGITLINK(patch->old_mode)) {
+			if (rmdir(patch->old_name))
+				warning("unable to remove submodule %s",
+					patch->old_name);
+		} else if (!unlink_or_warn(patch->old_name) && rmdir_empty) {
+			remove_path(patch->old_name);
+		}
+	}
+}
+
+static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
+{
+	struct stat st;
+	struct cache_entry *ce;
+	int namelen = strlen(path);
+	unsigned ce_size = cache_entry_size(namelen);
+
+	if (!update_index)
+		return;
+
+	ce = xcalloc(1, ce_size);
+	memcpy(ce->name, path, namelen);
+	ce->ce_mode = create_ce_mode(mode);
+	ce->ce_flags = namelen;
+	if (S_ISGITLINK(mode)) {
+		const char *s = buf;
+
+		if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
+			die("corrupt patch for subproject %s", path);
+	} else {
+		if (!cached) {
+			if (lstat(path, &st) < 0)
+				die_errno("unable to stat newly created file '%s'",
+					  path);
+			fill_stat_cache_info(ce, &st);
+		}
+		if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
+			die("unable to create backing store for newly created file %s", path);
+	}
+	if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
+		die("unable to add cache entry for %s", path);
+}
+
+static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
+{
+	int fd;
+	struct strbuf nbuf = STRBUF_INIT;
+
+	if (S_ISGITLINK(mode)) {
+		struct stat st;
+		if (!lstat(path, &st) && S_ISDIR(st.st_mode))
+			return 0;
+		return mkdir(path, 0777);
+	}
+
+	if (has_symlinks && S_ISLNK(mode))
+		/* Although buf:size is counted string, it also is NUL
+		 * terminated.
+		 */
+		return symlink(buf, path);
+
+	fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
+	if (fd < 0)
+		return -1;
+
+	if (convert_to_working_tree(path, buf, size, &nbuf)) {
+		size = nbuf.len;
+		buf  = nbuf.buf;
+	}
+	write_or_die(fd, buf, size);
+	strbuf_release(&nbuf);
+
+	if (close(fd) < 0)
+		die_errno("closing file '%s'", path);
+	return 0;
+}
+
+/*
+ * We optimistically assume that the directories exist,
+ * which is true 99% of the time anyway. If they don't,
+ * we create them and try again.
+ */
+static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
+{
+	if (cached)
+		return;
+	if (!try_create_file(path, mode, buf, size))
+		return;
+
+	if (errno == ENOENT) {
+		if (safe_create_leading_directories(path))
+			return;
+		if (!try_create_file(path, mode, buf, size))
+			return;
+	}
+
+	if (errno == EEXIST || errno == EACCES) {
+		/* We may be trying to create a file where a directory
+		 * used to be.
+		 */
+		struct stat st;
+		if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
+			errno = EEXIST;
+	}
+
+	if (errno == EEXIST) {
+		unsigned int nr = getpid();
+
+		for (;;) {
+			char newpath[PATH_MAX];
+			mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
+			if (!try_create_file(newpath, mode, buf, size)) {
+				if (!rename(newpath, path))
+					return;
+				unlink_or_warn(newpath);
+				break;
+			}
+			if (errno != EEXIST)
+				break;
+			++nr;
+		}
+	}
+	die_errno("unable to write file '%s' mode %o", path, mode);
+}
+
+static void create_file(struct patch *patch)
+{
+	char *path = patch->new_name;
+	unsigned mode = patch->new_mode;
+	unsigned long size = patch->resultsize;
+	char *buf = patch->result;
+
+	if (!mode)
+		mode = S_IFREG | 0644;
+	create_one_file(path, mode, buf, size);
+	add_index_file(path, mode, buf, size);
+}
+
+/* phase zero is to remove, phase one is to create */
+static void write_out_one_result(struct patch *patch, int phase)
+{
+	if (patch->is_delete > 0) {
+		if (phase == 0)
+			remove_file(patch, 1);
+		return;
+	}
+	if (patch->is_new > 0 || patch->is_copy) {
+		if (phase == 1)
+			create_file(patch);
+		return;
+	}
+	/*
+	 * Rename or modification boils down to the same
+	 * thing: remove the old, write the new
+	 */
+	if (phase == 0)
+		remove_file(patch, patch->is_rename);
+	if (phase == 1)
+		create_file(patch);
+}
+
+static int write_out_one_reject(struct patch *patch)
+{
+	FILE *rej;
+	char namebuf[PATH_MAX];
+	struct fragment *frag;
+	int cnt = 0;
+
+	for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
+		if (!frag->rejected)
+			continue;
+		cnt++;
+	}
+
+	if (!cnt) {
+		if (apply_verbosely)
+			say_patch_name(stderr,
+				       "Applied patch ", patch, " cleanly.\n");
+		return 0;
+	}
+
+	/* This should not happen, because a removal patch that leaves
+	 * contents are marked "rejected" at the patch level.
+	 */
+	if (!patch->new_name)
+		die("internal error");
+
+	/* Say this even without --verbose */
+	say_patch_name(stderr, "Applying patch ", patch, " with");
+	fprintf(stderr, " %d rejects...\n", cnt);
+
+	cnt = strlen(patch->new_name);
+	if (ARRAY_SIZE(namebuf) <= cnt + 5) {
+		cnt = ARRAY_SIZE(namebuf) - 5;
+		warning("truncating .rej filename to %.*s.rej",
+			cnt - 1, patch->new_name);
+	}
+	memcpy(namebuf, patch->new_name, cnt);
+	memcpy(namebuf + cnt, ".rej", 5);
+
+	rej = fopen(namebuf, "w");
+	if (!rej)
+		return error("cannot open %s: %s", namebuf, strerror(errno));
+
+	/* Normal git tools never deal with .rej, so do not pretend
+	 * this is a git patch by saying --git nor give extended
+	 * headers.  While at it, maybe please "kompare" that wants
+	 * the trailing TAB and some garbage at the end of line ;-).
+	 */
+	fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
+		patch->new_name, patch->new_name);
+	for (cnt = 1, frag = patch->fragments;
+	     frag;
+	     cnt++, frag = frag->next) {
+		if (!frag->rejected) {
+			fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
+			continue;
+		}
+		fprintf(stderr, "Rejected hunk #%d.\n", cnt);
+		fprintf(rej, "%.*s", frag->size, frag->patch);
+		if (frag->patch[frag->size-1] != '\n')
+			fputc('\n', rej);
+	}
+	fclose(rej);
+	return -1;
+}
+
+static int write_out_results(struct patch *list, int skipped_patch)
+{
+	int phase;
+	int errs = 0;
+	struct patch *l;
+
+	if (!list && !skipped_patch)
+		return error("No changes");
+
+	for (phase = 0; phase < 2; phase++) {
+		l = list;
+		while (l) {
+			if (l->rejected)
+				errs = 1;
+			else {
+				write_out_one_result(l, phase);
+				if (phase == 1 && write_out_one_reject(l))
+					errs = 1;
+			}
+			l = l->next;
+		}
+	}
+	return errs;
+}
+
+static struct lock_file lock_file;
+
+static struct string_list limit_by_name;
+static int has_include;
+static void add_name_limit(const char *name, int exclude)
+{
+	struct string_list_item *it;
+
+	it = string_list_append(name, &limit_by_name);
+	it->util = exclude ? NULL : (void *) 1;
+}
+
+static int use_patch(struct patch *p)
+{
+	const char *pathname = p->new_name ? p->new_name : p->old_name;
+	int i;
+
+	/* Paths outside are not touched regardless of "--include" */
+	if (0 < prefix_length) {
+		int pathlen = strlen(pathname);
+		if (pathlen <= prefix_length ||
+		    memcmp(prefix, pathname, prefix_length))
+			return 0;
+	}
+
+	/* See if it matches any of exclude/include rule */
+	for (i = 0; i < limit_by_name.nr; i++) {
+		struct string_list_item *it = &limit_by_name.items[i];
+		if (!fnmatch(it->string, pathname, 0))
+			return (it->util != NULL);
+	}
+
+	/*
+	 * If we had any include, a path that does not match any rule is
+	 * not used.  Otherwise, we saw bunch of exclude rules (or none)
+	 * and such a path is used.
+	 */
+	return !has_include;
+}
+
+
+static void prefix_one(char **name)
+{
+	char *old_name = *name;
+	if (!old_name)
+		return;
+	*name = xstrdup(prefix_filename(prefix, prefix_length, *name));
+	free(old_name);
+}
+
+static void prefix_patches(struct patch *p)
+{
+	if (!prefix || p->is_toplevel_relative)
+		return;
+	for ( ; p; p = p->next) {
+		if (p->new_name == p->old_name) {
+			char *prefixed = p->new_name;
+			prefix_one(&prefixed);
+			p->new_name = p->old_name = prefixed;
+		}
+		else {
+			prefix_one(&p->new_name);
+			prefix_one(&p->old_name);
+		}
+	}
+}
+
+#define INACCURATE_EOF	(1<<0)
+#define RECOUNT		(1<<1)
+
+static int apply_patch(int fd, const char *filename, int options)
+{
+	size_t offset;
+	struct strbuf buf = STRBUF_INIT;
+	struct patch *list = NULL, **listp = &list;
+	int skipped_patch = 0;
+
+	/* FIXME - memory leak when using multiple patch files as inputs */
+	memset(&fn_table, 0, sizeof(struct string_list));
+	patch_input_file = filename;
+	read_patch_file(&buf, fd);
+	offset = 0;
+	while (offset < buf.len) {
+		struct patch *patch;
+		int nr;
+
+		patch = xcalloc(1, sizeof(*patch));
+		patch->inaccurate_eof = !!(options & INACCURATE_EOF);
+		patch->recount =  !!(options & RECOUNT);
+		nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
+		if (nr < 0)
+			break;
+		if (apply_in_reverse)
+			reverse_patches(patch);
+		if (prefix)
+			prefix_patches(patch);
+		if (use_patch(patch)) {
+			patch_stats(patch);
+			*listp = patch;
+			listp = &patch->next;
+		}
+		else {
+			/* perhaps free it a bit better? */
+			free(patch);
+			skipped_patch++;
+		}
+		offset += nr;
+	}
+
+	if (whitespace_error && (ws_error_action == die_on_ws_error))
+		apply = 0;
+
+	update_index = check_index && apply;
+	if (update_index && newfd < 0)
+		newfd = hold_locked_index(&lock_file, 1);
+
+	if (check_index) {
+		if (read_cache() < 0)
+			die("unable to read index file");
+	}
+
+	if ((check || apply) &&
+	    check_patch_list(list) < 0 &&
+	    !apply_with_reject)
+		exit(1);
+
+	if (apply && write_out_results(list, skipped_patch))
+		exit(1);
+
+	if (fake_ancestor)
+		build_fake_ancestor(list, fake_ancestor);
+
+	if (diffstat)
+		stat_patch_list(list);
+
+	if (numstat)
+		numstat_patch_list(list);
+
+	if (summary)
+		summary_patch_list(list);
+
+	strbuf_release(&buf);
+	return 0;
+}
+
+static int git_apply_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "apply.whitespace"))
+		return git_config_string(&apply_default_whitespace, var, value);
+	else if (!strcmp(var, "apply.ignorewhitespace"))
+		return git_config_string(&apply_default_ignorewhitespace, var, value);
+	return git_default_config(var, value, cb);
+}
+
+static int option_parse_exclude(const struct option *opt,
+				const char *arg, int unset)
+{
+	add_name_limit(arg, 1);
+	return 0;
+}
+
+static int option_parse_include(const struct option *opt,
+				const char *arg, int unset)
+{
+	add_name_limit(arg, 0);
+	has_include = 1;
+	return 0;
+}
+
+static int option_parse_p(const struct option *opt,
+			  const char *arg, int unset)
+{
+	p_value = atoi(arg);
+	p_value_known = 1;
+	return 0;
+}
+
+static int option_parse_z(const struct option *opt,
+			  const char *arg, int unset)
+{
+	if (unset)
+		line_termination = '\n';
+	else
+		line_termination = 0;
+	return 0;
+}
+
+static int option_parse_space_change(const struct option *opt,
+			  const char *arg, int unset)
+{
+	if (unset)
+		ws_ignore_action = ignore_ws_none;
+	else
+		ws_ignore_action = ignore_ws_change;
+	return 0;
+}
+
+static int option_parse_whitespace(const struct option *opt,
+				   const char *arg, int unset)
+{
+	const char **whitespace_option = opt->value;
+
+	*whitespace_option = arg;
+	parse_whitespace_option(arg);
+	return 0;
+}
+
+static int option_parse_directory(const struct option *opt,
+				  const char *arg, int unset)
+{
+	root_len = strlen(arg);
+	if (root_len && arg[root_len - 1] != '/') {
+		char *new_root;
+		root = new_root = xmalloc(root_len + 2);
+		strcpy(new_root, arg);
+		strcpy(new_root + root_len++, "/");
+	} else
+		root = arg;
+	return 0;
+}
+
+int cmd_apply(int argc, const char **argv, const char *unused_prefix)
+{
+	int i;
+	int errs = 0;
+	int is_not_gitdir;
+	int binary;
+	int force_apply = 0;
+
+	const char *whitespace_option = NULL;
+
+	struct option builtin_apply_options[] = {
+		{ OPTION_CALLBACK, 0, "exclude", NULL, "path",
+			"don't apply changes matching the given path",
+			0, option_parse_exclude },
+		{ OPTION_CALLBACK, 0, "include", NULL, "path",
+			"apply changes matching the given path",
+			0, option_parse_include },
+		{ OPTION_CALLBACK, 'p', NULL, NULL, "num",
+			"remove <num> leading slashes from traditional diff paths",
+			0, option_parse_p },
+		OPT_BOOLEAN(0, "no-add", &no_add,
+			"ignore additions made by the patch"),
+		OPT_BOOLEAN(0, "stat", &diffstat,
+			"instead of applying the patch, output diffstat for the input"),
+		{ OPTION_BOOLEAN, 0, "allow-binary-replacement", &binary,
+		  NULL, "old option, now no-op",
+		  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG },
+		{ OPTION_BOOLEAN, 0, "binary", &binary,
+		  NULL, "old option, now no-op",
+		  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG },
+		OPT_BOOLEAN(0, "numstat", &numstat,
+			"shows number of added and deleted lines in decimal notation"),
+		OPT_BOOLEAN(0, "summary", &summary,
+			"instead of applying the patch, output a summary for the input"),
+		OPT_BOOLEAN(0, "check", &check,
+			"instead of applying the patch, see if the patch is applicable"),
+		OPT_BOOLEAN(0, "index", &check_index,
+			"make sure the patch is applicable to the current index"),
+		OPT_BOOLEAN(0, "cached", &cached,
+			"apply a patch without touching the working tree"),
+		OPT_BOOLEAN(0, "apply", &force_apply,
+			"also apply the patch (use with --stat/--summary/--check)"),
+		OPT_FILENAME(0, "build-fake-ancestor", &fake_ancestor,
+			"build a temporary index based on embedded index information"),
+		{ OPTION_CALLBACK, 'z', NULL, NULL, NULL,
+			"paths are separated with NUL character",
+			PARSE_OPT_NOARG, option_parse_z },
+		OPT_INTEGER('C', NULL, &p_context,
+				"ensure at least <n> lines of context match"),
+		{ OPTION_CALLBACK, 0, "whitespace", &whitespace_option, "action",
+			"detect new or modified lines that have whitespace errors",
+			0, option_parse_whitespace },
+		{ OPTION_CALLBACK, 0, "ignore-space-change", NULL, NULL,
+			"ignore changes in whitespace when finding context",
+			PARSE_OPT_NOARG, option_parse_space_change },
+		{ OPTION_CALLBACK, 0, "ignore-whitespace", NULL, NULL,
+			"ignore changes in whitespace when finding context",
+			PARSE_OPT_NOARG, option_parse_space_change },
+		OPT_BOOLEAN('R', "reverse", &apply_in_reverse,
+			"apply the patch in reverse"),
+		OPT_BOOLEAN(0, "unidiff-zero", &unidiff_zero,
+			"don't expect at least one line of context"),
+		OPT_BOOLEAN(0, "reject", &apply_with_reject,
+			"leave the rejected hunks in corresponding *.rej files"),
+		OPT__VERBOSE(&apply_verbosely),
+		OPT_BIT(0, "inaccurate-eof", &options,
+			"tolerate incorrectly detected missing new-line at the end of file",
+			INACCURATE_EOF),
+		OPT_BIT(0, "recount", &options,
+			"do not trust the line counts in the hunk headers",
+			RECOUNT),
+		{ OPTION_CALLBACK, 0, "directory", NULL, "root",
+			"prepend <root> to all filenames",
+			0, option_parse_directory },
+		OPT_END()
+	};
+
+	prefix = setup_git_directory_gently(&is_not_gitdir);
+	prefix_length = prefix ? strlen(prefix) : 0;
+	git_config(git_apply_config, NULL);
+	if (apply_default_whitespace)
+		parse_whitespace_option(apply_default_whitespace);
+	if (apply_default_ignorewhitespace)
+		parse_ignorewhitespace_option(apply_default_ignorewhitespace);
+
+	argc = parse_options(argc, argv, prefix, builtin_apply_options,
+			apply_usage, 0);
+
+	if (apply_with_reject)
+		apply = apply_verbosely = 1;
+	if (!force_apply && (diffstat || numstat || summary || check || fake_ancestor))
+		apply = 0;
+	if (check_index && is_not_gitdir)
+		die("--index outside a repository");
+	if (cached) {
+		if (is_not_gitdir)
+			die("--cached outside a repository");
+		check_index = 1;
+	}
+	for (i = 0; i < argc; i++) {
+		const char *arg = argv[i];
+		int fd;
+
+		if (!strcmp(arg, "-")) {
+			errs |= apply_patch(0, "<stdin>", options);
+			read_stdin = 0;
+			continue;
+		} else if (0 < prefix_length)
+			arg = prefix_filename(prefix, prefix_length, arg);
+
+		fd = open(arg, O_RDONLY);
+		if (fd < 0)
+			die_errno("can't open patch '%s'", arg);
+		read_stdin = 0;
+		set_default_whitespace_mode(whitespace_option);
+		errs |= apply_patch(fd, arg, options);
+		close(fd);
+	}
+	set_default_whitespace_mode(whitespace_option);
+	if (read_stdin)
+		errs |= apply_patch(0, "<stdin>", options);
+	if (whitespace_error) {
+		if (squelch_whitespace_errors &&
+		    squelch_whitespace_errors < whitespace_error) {
+			int squelched =
+				whitespace_error - squelch_whitespace_errors;
+			warning("squelched %d "
+				"whitespace error%s",
+				squelched,
+				squelched == 1 ? "" : "s");
+		}
+		if (ws_error_action == die_on_ws_error)
+			die("%d line%s add%s whitespace errors.",
+			    whitespace_error,
+			    whitespace_error == 1 ? "" : "s",
+			    whitespace_error == 1 ? "s" : "");
+		if (applied_after_fixing_ws && apply)
+			warning("%d line%s applied after"
+				" fixing whitespace errors.",
+				applied_after_fixing_ws,
+				applied_after_fixing_ws == 1 ? "" : "s");
+		else if (whitespace_error)
+			warning("%d line%s add%s whitespace errors.",
+				whitespace_error,
+				whitespace_error == 1 ? "" : "s",
+				whitespace_error == 1 ? "s" : "");
+	}
+
+	if (update_index) {
+		if (write_cache(newfd, active_cache, active_nr) ||
+		    commit_locked_index(&lock_file))
+			die("Unable to write new index file");
+	}
+
+	return !!errs;
+}
diff --git a/builtin/archive.c b/builtin/archive.c
new file mode 100644
index 0000000..6a887f5
--- /dev/null
+++ b/builtin/archive.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 2006 Franck Bui-Huu
+ * Copyright (c) 2006 Rene Scharfe
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "archive.h"
+#include "transport.h"
+#include "parse-options.h"
+#include "pkt-line.h"
+#include "sideband.h"
+
+static void create_output_file(const char *output_file)
+{
+	int output_fd = open(output_file, O_CREAT | O_WRONLY | O_TRUNC, 0666);
+	if (output_fd < 0)
+		die_errno("could not create archive file '%s'", output_file);
+	if (output_fd != 1) {
+		if (dup2(output_fd, 1) < 0)
+			die_errno("could not redirect output");
+		else
+			close(output_fd);
+	}
+}
+
+static int run_remote_archiver(int argc, const char **argv,
+			       const char *remote, const char *exec)
+{
+	char buf[LARGE_PACKET_MAX];
+	int fd[2], i, len, rv;
+	struct transport *transport;
+	struct remote *_remote;
+
+	_remote = remote_get(remote);
+	if (!_remote->url[0])
+		die("git archive: Remote with no URL");
+	transport = transport_get(_remote, _remote->url[0]);
+	transport_connect(transport, "git-upload-archive", exec, fd);
+
+	for (i = 1; i < argc; i++)
+		packet_write(fd[1], "argument %s\n", argv[i]);
+	packet_flush(fd[1]);
+
+	len = packet_read_line(fd[0], buf, sizeof(buf));
+	if (!len)
+		die("git archive: expected ACK/NAK, got EOF");
+	if (buf[len-1] == '\n')
+		buf[--len] = 0;
+	if (strcmp(buf, "ACK")) {
+		if (len > 5 && !prefixcmp(buf, "NACK "))
+			die("git archive: NACK %s", buf + 5);
+		die("git archive: protocol error");
+	}
+
+	len = packet_read_line(fd[0], buf, sizeof(buf));
+	if (len)
+		die("git archive: expected a flush");
+
+	/* Now, start reading from fd[0] and spit it out to stdout */
+	rv = recv_sideband("archive", fd[0], 1);
+	rv |= transport_disconnect(transport);
+
+	return !!rv;
+}
+
+static const char *format_from_name(const char *filename)
+{
+	const char *ext = strrchr(filename, '.');
+	if (!ext)
+		return NULL;
+	ext++;
+	if (!strcasecmp(ext, "zip"))
+		return "--format=zip";
+	return NULL;
+}
+
+#define PARSE_OPT_KEEP_ALL ( PARSE_OPT_KEEP_DASHDASH | 	\
+			     PARSE_OPT_KEEP_ARGV0 | 	\
+			     PARSE_OPT_KEEP_UNKNOWN |	\
+			     PARSE_OPT_NO_INTERNAL_HELP	)
+
+int cmd_archive(int argc, const char **argv, const char *prefix)
+{
+	const char *exec = "git-upload-archive";
+	const char *output = NULL;
+	const char *remote = NULL;
+	const char *format_option = NULL;
+	struct option local_opts[] = {
+		OPT_STRING('o', "output", &output, "file",
+			"write the archive to this file"),
+		OPT_STRING(0, "remote", &remote, "repo",
+			"retrieve the archive from remote repository <repo>"),
+		OPT_STRING(0, "exec", &exec, "cmd",
+			"path to the remote git-upload-archive command"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, local_opts, NULL,
+			     PARSE_OPT_KEEP_ALL);
+
+	if (output) {
+		create_output_file(output);
+		format_option = format_from_name(output);
+	}
+
+	/*
+	 * We have enough room in argv[] to muck it in place, because
+	 * --output must have been given on the original command line
+	 * if we get to this point, and parse_options() must have eaten
+	 * it, i.e. we can add back one element to the array.
+	 *
+	 * We add a fake --format option at the beginning, with the
+	 * format inferred from our output filename.  This way explicit
+	 * --format options can override it, and the fake option is
+	 * inserted before any "--" that might have been given.
+	 */
+	if (format_option) {
+		memmove(argv + 2, argv + 1, sizeof(*argv) * argc);
+		argv[1] = format_option;
+		argv[++argc] = NULL;
+	}
+
+	if (remote)
+		return run_remote_archiver(argc, argv, remote, exec);
+
+	setvbuf(stderr, NULL, _IOLBF, BUFSIZ);
+
+	return write_archive(argc, argv, prefix, 1);
+}
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
new file mode 100644
index 0000000..5b22639
--- /dev/null
+++ b/builtin/bisect--helper.c
@@ -0,0 +1,28 @@
+#include "builtin.h"
+#include "cache.h"
+#include "parse-options.h"
+#include "bisect.h"
+
+static const char * const git_bisect_helper_usage[] = {
+	"git bisect--helper --next-all",
+	NULL
+};
+
+int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
+{
+	int next_all = 0;
+	struct option options[] = {
+		OPT_BOOLEAN(0, "next-all", &next_all,
+			    "perform 'git bisect next'"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, options,
+			     git_bisect_helper_usage, 0);
+
+	if (!next_all)
+		usage_with_options(git_bisect_helper_usage, options);
+
+	/* next-all */
+	return bisect_next_all(prefix);
+}
diff --git a/builtin/blame.c b/builtin/blame.c
new file mode 100644
index 0000000..10f7eac
--- /dev/null
+++ b/builtin/blame.c
@@ -0,0 +1,2477 @@
+/*
+ * Blame
+ *
+ * Copyright (c) 2006, Junio C Hamano
+ */
+
+#include "cache.h"
+#include "builtin.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree-walk.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "revision.h"
+#include "quote.h"
+#include "xdiff-interface.h"
+#include "cache-tree.h"
+#include "string-list.h"
+#include "mailmap.h"
+#include "parse-options.h"
+#include "utf8.h"
+
+static char blame_usage[] = "git blame [options] [rev-opts] [rev] [--] file";
+
+static const char *blame_opt_usage[] = {
+	blame_usage,
+	"",
+	"[rev-opts] are documented in git-rev-list(1)",
+	NULL
+};
+
+static int longest_file;
+static int longest_author;
+static int max_orig_digits;
+static int max_digits;
+static int max_score_digits;
+static int show_root;
+static int reverse;
+static int blank_boundary;
+static int incremental;
+static int xdl_opts = XDF_NEED_MINIMAL;
+
+static enum date_mode blame_date_mode = DATE_ISO8601;
+static size_t blame_date_width;
+
+static struct string_list mailmap;
+
+#ifndef DEBUG
+#define DEBUG 0
+#endif
+
+/* stats */
+static int num_read_blob;
+static int num_get_patch;
+static int num_commits;
+
+#define PICKAXE_BLAME_MOVE		01
+#define PICKAXE_BLAME_COPY		02
+#define PICKAXE_BLAME_COPY_HARDER	04
+#define PICKAXE_BLAME_COPY_HARDEST	010
+
+/*
+ * blame for a blame_entry with score lower than these thresholds
+ * is not passed to the parent using move/copy logic.
+ */
+static unsigned blame_move_score;
+static unsigned blame_copy_score;
+#define BLAME_DEFAULT_MOVE_SCORE	20
+#define BLAME_DEFAULT_COPY_SCORE	40
+
+/* bits #0..7 in revision.h, #8..11 used for merge_bases() in commit.c */
+#define METAINFO_SHOWN		(1u<<12)
+#define MORE_THAN_ONE_PATH	(1u<<13)
+
+/*
+ * One blob in a commit that is being suspected
+ */
+struct origin {
+	int refcnt;
+	struct origin *previous;
+	struct commit *commit;
+	mmfile_t file;
+	unsigned char blob_sha1[20];
+	char path[FLEX_ARRAY];
+};
+
+/*
+ * Given an origin, prepare mmfile_t structure to be used by the
+ * diff machinery
+ */
+static void fill_origin_blob(struct origin *o, mmfile_t *file)
+{
+	if (!o->file.ptr) {
+		enum object_type type;
+		num_read_blob++;
+		file->ptr = read_sha1_file(o->blob_sha1, &type,
+					   (unsigned long *)(&(file->size)));
+		if (!file->ptr)
+			die("Cannot read blob %s for path %s",
+			    sha1_to_hex(o->blob_sha1),
+			    o->path);
+		o->file = *file;
+	}
+	else
+		*file = o->file;
+}
+
+/*
+ * Origin is refcounted and usually we keep the blob contents to be
+ * reused.
+ */
+static inline struct origin *origin_incref(struct origin *o)
+{
+	if (o)
+		o->refcnt++;
+	return o;
+}
+
+static void origin_decref(struct origin *o)
+{
+	if (o && --o->refcnt <= 0) {
+		if (o->previous)
+			origin_decref(o->previous);
+		free(o->file.ptr);
+		free(o);
+	}
+}
+
+static void drop_origin_blob(struct origin *o)
+{
+	if (o->file.ptr) {
+		free(o->file.ptr);
+		o->file.ptr = NULL;
+	}
+}
+
+/*
+ * Each group of lines is described by a blame_entry; it can be split
+ * as we pass blame to the parents.  They form a linked list in the
+ * scoreboard structure, sorted by the target line number.
+ */
+struct blame_entry {
+	struct blame_entry *prev;
+	struct blame_entry *next;
+
+	/* the first line of this group in the final image;
+	 * internally all line numbers are 0 based.
+	 */
+	int lno;
+
+	/* how many lines this group has */
+	int num_lines;
+
+	/* the commit that introduced this group into the final image */
+	struct origin *suspect;
+
+	/* true if the suspect is truly guilty; false while we have not
+	 * checked if the group came from one of its parents.
+	 */
+	char guilty;
+
+	/* true if the entry has been scanned for copies in the current parent
+	 */
+	char scanned;
+
+	/* the line number of the first line of this group in the
+	 * suspect's file; internally all line numbers are 0 based.
+	 */
+	int s_lno;
+
+	/* how significant this entry is -- cached to avoid
+	 * scanning the lines over and over.
+	 */
+	unsigned score;
+};
+
+/*
+ * The current state of the blame assignment.
+ */
+struct scoreboard {
+	/* the final commit (i.e. where we started digging from) */
+	struct commit *final;
+	struct rev_info *revs;
+	const char *path;
+
+	/*
+	 * The contents in the final image.
+	 * Used by many functions to obtain contents of the nth line,
+	 * indexed with scoreboard.lineno[blame_entry.lno].
+	 */
+	const char *final_buf;
+	unsigned long final_buf_size;
+
+	/* linked list of blames */
+	struct blame_entry *ent;
+
+	/* look-up a line in the final buffer */
+	int num_lines;
+	int *lineno;
+};
+
+static inline int same_suspect(struct origin *a, struct origin *b)
+{
+	if (a == b)
+		return 1;
+	if (a->commit != b->commit)
+		return 0;
+	return !strcmp(a->path, b->path);
+}
+
+static void sanity_check_refcnt(struct scoreboard *);
+
+/*
+ * If two blame entries that are next to each other came from
+ * contiguous lines in the same origin (i.e. <commit, path> pair),
+ * merge them together.
+ */
+static void coalesce(struct scoreboard *sb)
+{
+	struct blame_entry *ent, *next;
+
+	for (ent = sb->ent; ent && (next = ent->next); ent = next) {
+		if (same_suspect(ent->suspect, next->suspect) &&
+		    ent->guilty == next->guilty &&
+		    ent->s_lno + ent->num_lines == next->s_lno) {
+			ent->num_lines += next->num_lines;
+			ent->next = next->next;
+			if (ent->next)
+				ent->next->prev = ent;
+			origin_decref(next->suspect);
+			free(next);
+			ent->score = 0;
+			next = ent; /* again */
+		}
+	}
+
+	if (DEBUG) /* sanity */
+		sanity_check_refcnt(sb);
+}
+
+/*
+ * Given a commit and a path in it, create a new origin structure.
+ * The callers that add blame to the scoreboard should use
+ * get_origin() to obtain shared, refcounted copy instead of calling
+ * this function directly.
+ */
+static struct origin *make_origin(struct commit *commit, const char *path)
+{
+	struct origin *o;
+	o = xcalloc(1, sizeof(*o) + strlen(path) + 1);
+	o->commit = commit;
+	o->refcnt = 1;
+	strcpy(o->path, path);
+	return o;
+}
+
+/*
+ * Locate an existing origin or create a new one.
+ */
+static struct origin *get_origin(struct scoreboard *sb,
+				 struct commit *commit,
+				 const char *path)
+{
+	struct blame_entry *e;
+
+	for (e = sb->ent; e; e = e->next) {
+		if (e->suspect->commit == commit &&
+		    !strcmp(e->suspect->path, path))
+			return origin_incref(e->suspect);
+	}
+	return make_origin(commit, path);
+}
+
+/*
+ * Fill the blob_sha1 field of an origin if it hasn't, so that later
+ * call to fill_origin_blob() can use it to locate the data.  blob_sha1
+ * for an origin is also used to pass the blame for the entire file to
+ * the parent to detect the case where a child's blob is identical to
+ * that of its parent's.
+ */
+static int fill_blob_sha1(struct origin *origin)
+{
+	unsigned mode;
+
+	if (!is_null_sha1(origin->blob_sha1))
+		return 0;
+	if (get_tree_entry(origin->commit->object.sha1,
+			   origin->path,
+			   origin->blob_sha1, &mode))
+		goto error_out;
+	if (sha1_object_info(origin->blob_sha1, NULL) != OBJ_BLOB)
+		goto error_out;
+	return 0;
+ error_out:
+	hashclr(origin->blob_sha1);
+	return -1;
+}
+
+/*
+ * We have an origin -- check if the same path exists in the
+ * parent and return an origin structure to represent it.
+ */
+static struct origin *find_origin(struct scoreboard *sb,
+				  struct commit *parent,
+				  struct origin *origin)
+{
+	struct origin *porigin = NULL;
+	struct diff_options diff_opts;
+	const char *paths[2];
+
+	if (parent->util) {
+		/*
+		 * Each commit object can cache one origin in that
+		 * commit.  This is a freestanding copy of origin and
+		 * not refcounted.
+		 */
+		struct origin *cached = parent->util;
+		if (!strcmp(cached->path, origin->path)) {
+			/*
+			 * The same path between origin and its parent
+			 * without renaming -- the most common case.
+			 */
+			porigin = get_origin(sb, parent, cached->path);
+
+			/*
+			 * If the origin was newly created (i.e. get_origin
+			 * would call make_origin if none is found in the
+			 * scoreboard), it does not know the blob_sha1,
+			 * so copy it.  Otherwise porigin was in the
+			 * scoreboard and already knows blob_sha1.
+			 */
+			if (porigin->refcnt == 1)
+				hashcpy(porigin->blob_sha1, cached->blob_sha1);
+			return porigin;
+		}
+		/* otherwise it was not very useful; free it */
+		free(parent->util);
+		parent->util = NULL;
+	}
+
+	/* See if the origin->path is different between parent
+	 * and origin first.  Most of the time they are the
+	 * same and diff-tree is fairly efficient about this.
+	 */
+	diff_setup(&diff_opts);
+	DIFF_OPT_SET(&diff_opts, RECURSIVE);
+	diff_opts.detect_rename = 0;
+	diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+	paths[0] = origin->path;
+	paths[1] = NULL;
+
+	diff_tree_setup_paths(paths, &diff_opts);
+	if (diff_setup_done(&diff_opts) < 0)
+		die("diff-setup");
+
+	if (is_null_sha1(origin->commit->object.sha1))
+		do_diff_cache(parent->tree->object.sha1, &diff_opts);
+	else
+		diff_tree_sha1(parent->tree->object.sha1,
+			       origin->commit->tree->object.sha1,
+			       "", &diff_opts);
+	diffcore_std(&diff_opts);
+
+	if (!diff_queued_diff.nr) {
+		/* The path is the same as parent */
+		porigin = get_origin(sb, parent, origin->path);
+		hashcpy(porigin->blob_sha1, origin->blob_sha1);
+	} else {
+		/*
+		 * Since origin->path is a pathspec, if the parent
+		 * commit had it as a directory, we will see a whole
+		 * bunch of deletion of files in the directory that we
+		 * do not care about.
+		 */
+		int i;
+		struct diff_filepair *p = NULL;
+		for (i = 0; i < diff_queued_diff.nr; i++) {
+			const char *name;
+			p = diff_queued_diff.queue[i];
+			name = p->one->path ? p->one->path : p->two->path;
+			if (!strcmp(name, origin->path))
+				break;
+		}
+		if (!p)
+			die("internal error in blame::find_origin");
+		switch (p->status) {
+		default:
+			die("internal error in blame::find_origin (%c)",
+			    p->status);
+		case 'M':
+			porigin = get_origin(sb, parent, origin->path);
+			hashcpy(porigin->blob_sha1, p->one->sha1);
+			break;
+		case 'A':
+		case 'T':
+			/* Did not exist in parent, or type changed */
+			break;
+		}
+	}
+	diff_flush(&diff_opts);
+	diff_tree_release_paths(&diff_opts);
+	if (porigin) {
+		/*
+		 * Create a freestanding copy that is not part of
+		 * the refcounted origin found in the scoreboard, and
+		 * cache it in the commit.
+		 */
+		struct origin *cached;
+
+		cached = make_origin(porigin->commit, porigin->path);
+		hashcpy(cached->blob_sha1, porigin->blob_sha1);
+		parent->util = cached;
+	}
+	return porigin;
+}
+
+/*
+ * We have an origin -- find the path that corresponds to it in its
+ * parent and return an origin structure to represent it.
+ */
+static struct origin *find_rename(struct scoreboard *sb,
+				  struct commit *parent,
+				  struct origin *origin)
+{
+	struct origin *porigin = NULL;
+	struct diff_options diff_opts;
+	int i;
+	const char *paths[2];
+
+	diff_setup(&diff_opts);
+	DIFF_OPT_SET(&diff_opts, RECURSIVE);
+	diff_opts.detect_rename = DIFF_DETECT_RENAME;
+	diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+	diff_opts.single_follow = origin->path;
+	paths[0] = NULL;
+	diff_tree_setup_paths(paths, &diff_opts);
+	if (diff_setup_done(&diff_opts) < 0)
+		die("diff-setup");
+
+	if (is_null_sha1(origin->commit->object.sha1))
+		do_diff_cache(parent->tree->object.sha1, &diff_opts);
+	else
+		diff_tree_sha1(parent->tree->object.sha1,
+			       origin->commit->tree->object.sha1,
+			       "", &diff_opts);
+	diffcore_std(&diff_opts);
+
+	for (i = 0; i < diff_queued_diff.nr; i++) {
+		struct diff_filepair *p = diff_queued_diff.queue[i];
+		if ((p->status == 'R' || p->status == 'C') &&
+		    !strcmp(p->two->path, origin->path)) {
+			porigin = get_origin(sb, parent, p->one->path);
+			hashcpy(porigin->blob_sha1, p->one->sha1);
+			break;
+		}
+	}
+	diff_flush(&diff_opts);
+	diff_tree_release_paths(&diff_opts);
+	return porigin;
+}
+
+/*
+ * Link in a new blame entry to the scoreboard.  Entries that cover the
+ * same line range have been removed from the scoreboard previously.
+ */
+static void add_blame_entry(struct scoreboard *sb, struct blame_entry *e)
+{
+	struct blame_entry *ent, *prev = NULL;
+
+	origin_incref(e->suspect);
+
+	for (ent = sb->ent; ent && ent->lno < e->lno; ent = ent->next)
+		prev = ent;
+
+	/* prev, if not NULL, is the last one that is below e */
+	e->prev = prev;
+	if (prev) {
+		e->next = prev->next;
+		prev->next = e;
+	}
+	else {
+		e->next = sb->ent;
+		sb->ent = e;
+	}
+	if (e->next)
+		e->next->prev = e;
+}
+
+/*
+ * src typically is on-stack; we want to copy the information in it to
+ * a malloced blame_entry that is already on the linked list of the
+ * scoreboard.  The origin of dst loses a refcnt while the origin of src
+ * gains one.
+ */
+static void dup_entry(struct blame_entry *dst, struct blame_entry *src)
+{
+	struct blame_entry *p, *n;
+
+	p = dst->prev;
+	n = dst->next;
+	origin_incref(src->suspect);
+	origin_decref(dst->suspect);
+	memcpy(dst, src, sizeof(*src));
+	dst->prev = p;
+	dst->next = n;
+	dst->score = 0;
+}
+
+static const char *nth_line(struct scoreboard *sb, int lno)
+{
+	return sb->final_buf + sb->lineno[lno];
+}
+
+/*
+ * It is known that lines between tlno to same came from parent, and e
+ * has an overlap with that range.  it also is known that parent's
+ * line plno corresponds to e's line tlno.
+ *
+ *                <---- e ----->
+ *                   <------>
+ *                   <------------>
+ *             <------------>
+ *             <------------------>
+ *
+ * Split e into potentially three parts; before this chunk, the chunk
+ * to be blamed for the parent, and after that portion.
+ */
+static void split_overlap(struct blame_entry *split,
+			  struct blame_entry *e,
+			  int tlno, int plno, int same,
+			  struct origin *parent)
+{
+	int chunk_end_lno;
+	memset(split, 0, sizeof(struct blame_entry [3]));
+
+	if (e->s_lno < tlno) {
+		/* there is a pre-chunk part not blamed on parent */
+		split[0].suspect = origin_incref(e->suspect);
+		split[0].lno = e->lno;
+		split[0].s_lno = e->s_lno;
+		split[0].num_lines = tlno - e->s_lno;
+		split[1].lno = e->lno + tlno - e->s_lno;
+		split[1].s_lno = plno;
+	}
+	else {
+		split[1].lno = e->lno;
+		split[1].s_lno = plno + (e->s_lno - tlno);
+	}
+
+	if (same < e->s_lno + e->num_lines) {
+		/* there is a post-chunk part not blamed on parent */
+		split[2].suspect = origin_incref(e->suspect);
+		split[2].lno = e->lno + (same - e->s_lno);
+		split[2].s_lno = e->s_lno + (same - e->s_lno);
+		split[2].num_lines = e->s_lno + e->num_lines - same;
+		chunk_end_lno = split[2].lno;
+	}
+	else
+		chunk_end_lno = e->lno + e->num_lines;
+	split[1].num_lines = chunk_end_lno - split[1].lno;
+
+	/*
+	 * if it turns out there is nothing to blame the parent for,
+	 * forget about the splitting.  !split[1].suspect signals this.
+	 */
+	if (split[1].num_lines < 1)
+		return;
+	split[1].suspect = origin_incref(parent);
+}
+
+/*
+ * split_overlap() divided an existing blame e into up to three parts
+ * in split.  Adjust the linked list of blames in the scoreboard to
+ * reflect the split.
+ */
+static void split_blame(struct scoreboard *sb,
+			struct blame_entry *split,
+			struct blame_entry *e)
+{
+	struct blame_entry *new_entry;
+
+	if (split[0].suspect && split[2].suspect) {
+		/* The first part (reuse storage for the existing entry e) */
+		dup_entry(e, &split[0]);
+
+		/* The last part -- me */
+		new_entry = xmalloc(sizeof(*new_entry));
+		memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
+		add_blame_entry(sb, new_entry);
+
+		/* ... and the middle part -- parent */
+		new_entry = xmalloc(sizeof(*new_entry));
+		memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
+		add_blame_entry(sb, new_entry);
+	}
+	else if (!split[0].suspect && !split[2].suspect)
+		/*
+		 * The parent covers the entire area; reuse storage for
+		 * e and replace it with the parent.
+		 */
+		dup_entry(e, &split[1]);
+	else if (split[0].suspect) {
+		/* me and then parent */
+		dup_entry(e, &split[0]);
+
+		new_entry = xmalloc(sizeof(*new_entry));
+		memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
+		add_blame_entry(sb, new_entry);
+	}
+	else {
+		/* parent and then me */
+		dup_entry(e, &split[1]);
+
+		new_entry = xmalloc(sizeof(*new_entry));
+		memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
+		add_blame_entry(sb, new_entry);
+	}
+
+	if (DEBUG) { /* sanity */
+		struct blame_entry *ent;
+		int lno = sb->ent->lno, corrupt = 0;
+
+		for (ent = sb->ent; ent; ent = ent->next) {
+			if (lno != ent->lno)
+				corrupt = 1;
+			if (ent->s_lno < 0)
+				corrupt = 1;
+			lno += ent->num_lines;
+		}
+		if (corrupt) {
+			lno = sb->ent->lno;
+			for (ent = sb->ent; ent; ent = ent->next) {
+				printf("L %8d l %8d n %8d\n",
+				       lno, ent->lno, ent->num_lines);
+				lno = ent->lno + ent->num_lines;
+			}
+			die("oops");
+		}
+	}
+}
+
+/*
+ * After splitting the blame, the origins used by the
+ * on-stack blame_entry should lose one refcnt each.
+ */
+static void decref_split(struct blame_entry *split)
+{
+	int i;
+
+	for (i = 0; i < 3; i++)
+		origin_decref(split[i].suspect);
+}
+
+/*
+ * Helper for blame_chunk().  blame_entry e is known to overlap with
+ * the patch hunk; split it and pass blame to the parent.
+ */
+static void blame_overlap(struct scoreboard *sb, struct blame_entry *e,
+			  int tlno, int plno, int same,
+			  struct origin *parent)
+{
+	struct blame_entry split[3];
+
+	split_overlap(split, e, tlno, plno, same, parent);
+	if (split[1].suspect)
+		split_blame(sb, split, e);
+	decref_split(split);
+}
+
+/*
+ * Find the line number of the last line the target is suspected for.
+ */
+static int find_last_in_target(struct scoreboard *sb, struct origin *target)
+{
+	struct blame_entry *e;
+	int last_in_target = -1;
+
+	for (e = sb->ent; e; e = e->next) {
+		if (e->guilty || !same_suspect(e->suspect, target))
+			continue;
+		if (last_in_target < e->s_lno + e->num_lines)
+			last_in_target = e->s_lno + e->num_lines;
+	}
+	return last_in_target;
+}
+
+/*
+ * Process one hunk from the patch between the current suspect for
+ * blame_entry e and its parent.  Find and split the overlap, and
+ * pass blame to the overlapping part to the parent.
+ */
+static void blame_chunk(struct scoreboard *sb,
+			int tlno, int plno, int same,
+			struct origin *target, struct origin *parent)
+{
+	struct blame_entry *e;
+
+	for (e = sb->ent; e; e = e->next) {
+		if (e->guilty || !same_suspect(e->suspect, target))
+			continue;
+		if (same <= e->s_lno)
+			continue;
+		if (tlno < e->s_lno + e->num_lines)
+			blame_overlap(sb, e, tlno, plno, same, parent);
+	}
+}
+
+struct blame_chunk_cb_data {
+	struct scoreboard *sb;
+	struct origin *target;
+	struct origin *parent;
+	long plno;
+	long tlno;
+};
+
+static void blame_chunk_cb(void *data, long same, long p_next, long t_next)
+{
+	struct blame_chunk_cb_data *d = data;
+	blame_chunk(d->sb, d->tlno, d->plno, same, d->target, d->parent);
+	d->plno = p_next;
+	d->tlno = t_next;
+}
+
+/*
+ * We are looking at the origin 'target' and aiming to pass blame
+ * for the lines it is suspected to its parent.  Run diff to find
+ * which lines came from parent and pass blame for them.
+ */
+static int pass_blame_to_parent(struct scoreboard *sb,
+				struct origin *target,
+				struct origin *parent)
+{
+	int last_in_target;
+	mmfile_t file_p, file_o;
+	struct blame_chunk_cb_data d = { sb, target, parent, 0, 0 };
+	xpparam_t xpp;
+	xdemitconf_t xecfg;
+
+	last_in_target = find_last_in_target(sb, target);
+	if (last_in_target < 0)
+		return 1; /* nothing remains for this target */
+
+	fill_origin_blob(parent, &file_p);
+	fill_origin_blob(target, &file_o);
+	num_get_patch++;
+
+	memset(&xpp, 0, sizeof(xpp));
+	xpp.flags = xdl_opts;
+	memset(&xecfg, 0, sizeof(xecfg));
+	xecfg.ctxlen = 0;
+	xdi_diff_hunks(&file_p, &file_o, blame_chunk_cb, &d, &xpp, &xecfg);
+	/* The rest (i.e. anything after tlno) are the same as the parent */
+	blame_chunk(sb, d.tlno, d.plno, last_in_target, target, parent);
+
+	return 0;
+}
+
+/*
+ * The lines in blame_entry after splitting blames many times can become
+ * very small and trivial, and at some point it becomes pointless to
+ * blame the parents.  E.g. "\t\t}\n\t}\n\n" appears everywhere in any
+ * ordinary C program, and it is not worth to say it was copied from
+ * totally unrelated file in the parent.
+ *
+ * Compute how trivial the lines in the blame_entry are.
+ */
+static unsigned ent_score(struct scoreboard *sb, struct blame_entry *e)
+{
+	unsigned score;
+	const char *cp, *ep;
+
+	if (e->score)
+		return e->score;
+
+	score = 1;
+	cp = nth_line(sb, e->lno);
+	ep = nth_line(sb, e->lno + e->num_lines);
+	while (cp < ep) {
+		unsigned ch = *((unsigned char *)cp);
+		if (isalnum(ch))
+			score++;
+		cp++;
+	}
+	e->score = score;
+	return score;
+}
+
+/*
+ * best_so_far[] and this[] are both a split of an existing blame_entry
+ * that passes blame to the parent.  Maintain best_so_far the best split
+ * so far, by comparing this and best_so_far and copying this into
+ * bst_so_far as needed.
+ */
+static void copy_split_if_better(struct scoreboard *sb,
+				 struct blame_entry *best_so_far,
+				 struct blame_entry *this)
+{
+	int i;
+
+	if (!this[1].suspect)
+		return;
+	if (best_so_far[1].suspect) {
+		if (ent_score(sb, &this[1]) < ent_score(sb, &best_so_far[1]))
+			return;
+	}
+
+	for (i = 0; i < 3; i++)
+		origin_incref(this[i].suspect);
+	decref_split(best_so_far);
+	memcpy(best_so_far, this, sizeof(struct blame_entry [3]));
+}
+
+/*
+ * We are looking at a part of the final image represented by
+ * ent (tlno and same are offset by ent->s_lno).
+ * tlno is where we are looking at in the final image.
+ * up to (but not including) same match preimage.
+ * plno is where we are looking at in the preimage.
+ *
+ * <-------------- final image ---------------------->
+ *       <------ent------>
+ *         ^tlno ^same
+ *    <---------preimage----->
+ *         ^plno
+ *
+ * All line numbers are 0-based.
+ */
+static void handle_split(struct scoreboard *sb,
+			 struct blame_entry *ent,
+			 int tlno, int plno, int same,
+			 struct origin *parent,
+			 struct blame_entry *split)
+{
+	if (ent->num_lines <= tlno)
+		return;
+	if (tlno < same) {
+		struct blame_entry this[3];
+		tlno += ent->s_lno;
+		same += ent->s_lno;
+		split_overlap(this, ent, tlno, plno, same, parent);
+		copy_split_if_better(sb, split, this);
+		decref_split(this);
+	}
+}
+
+struct handle_split_cb_data {
+	struct scoreboard *sb;
+	struct blame_entry *ent;
+	struct origin *parent;
+	struct blame_entry *split;
+	long plno;
+	long tlno;
+};
+
+static void handle_split_cb(void *data, long same, long p_next, long t_next)
+{
+	struct handle_split_cb_data *d = data;
+	handle_split(d->sb, d->ent, d->tlno, d->plno, same, d->parent, d->split);
+	d->plno = p_next;
+	d->tlno = t_next;
+}
+
+/*
+ * Find the lines from parent that are the same as ent so that
+ * we can pass blames to it.  file_p has the blob contents for
+ * the parent.
+ */
+static void find_copy_in_blob(struct scoreboard *sb,
+			      struct blame_entry *ent,
+			      struct origin *parent,
+			      struct blame_entry *split,
+			      mmfile_t *file_p)
+{
+	const char *cp;
+	int cnt;
+	mmfile_t file_o;
+	struct handle_split_cb_data d = { sb, ent, parent, split, 0, 0 };
+	xpparam_t xpp;
+	xdemitconf_t xecfg;
+
+	/*
+	 * Prepare mmfile that contains only the lines in ent.
+	 */
+	cp = nth_line(sb, ent->lno);
+	file_o.ptr = (char *) cp;
+	cnt = ent->num_lines;
+
+	while (cnt && cp < sb->final_buf + sb->final_buf_size) {
+		if (*cp++ == '\n')
+			cnt--;
+	}
+	file_o.size = cp - file_o.ptr;
+
+	/*
+	 * file_o is a part of final image we are annotating.
+	 * file_p partially may match that image.
+	 */
+	memset(&xpp, 0, sizeof(xpp));
+	xpp.flags = xdl_opts;
+	memset(&xecfg, 0, sizeof(xecfg));
+	xecfg.ctxlen = 1;
+	memset(split, 0, sizeof(struct blame_entry [3]));
+	xdi_diff_hunks(file_p, &file_o, handle_split_cb, &d, &xpp, &xecfg);
+	/* remainder, if any, all match the preimage */
+	handle_split(sb, ent, d.tlno, d.plno, ent->num_lines, parent, split);
+}
+
+/*
+ * See if lines currently target is suspected for can be attributed to
+ * parent.
+ */
+static int find_move_in_parent(struct scoreboard *sb,
+			       struct origin *target,
+			       struct origin *parent)
+{
+	int last_in_target, made_progress;
+	struct blame_entry *e, split[3];
+	mmfile_t file_p;
+
+	last_in_target = find_last_in_target(sb, target);
+	if (last_in_target < 0)
+		return 1; /* nothing remains for this target */
+
+	fill_origin_blob(parent, &file_p);
+	if (!file_p.ptr)
+		return 0;
+
+	made_progress = 1;
+	while (made_progress) {
+		made_progress = 0;
+		for (e = sb->ent; e; e = e->next) {
+			if (e->guilty || !same_suspect(e->suspect, target) ||
+			    ent_score(sb, e) < blame_move_score)
+				continue;
+			find_copy_in_blob(sb, e, parent, split, &file_p);
+			if (split[1].suspect &&
+			    blame_move_score < ent_score(sb, &split[1])) {
+				split_blame(sb, split, e);
+				made_progress = 1;
+			}
+			decref_split(split);
+		}
+	}
+	return 0;
+}
+
+struct blame_list {
+	struct blame_entry *ent;
+	struct blame_entry split[3];
+};
+
+/*
+ * Count the number of entries the target is suspected for,
+ * and prepare a list of entry and the best split.
+ */
+static struct blame_list *setup_blame_list(struct scoreboard *sb,
+					   struct origin *target,
+					   int min_score,
+					   int *num_ents_p)
+{
+	struct blame_entry *e;
+	int num_ents, i;
+	struct blame_list *blame_list = NULL;
+
+	for (e = sb->ent, num_ents = 0; e; e = e->next)
+		if (!e->scanned && !e->guilty &&
+		    same_suspect(e->suspect, target) &&
+		    min_score < ent_score(sb, e))
+			num_ents++;
+	if (num_ents) {
+		blame_list = xcalloc(num_ents, sizeof(struct blame_list));
+		for (e = sb->ent, i = 0; e; e = e->next)
+			if (!e->scanned && !e->guilty &&
+			    same_suspect(e->suspect, target) &&
+			    min_score < ent_score(sb, e))
+				blame_list[i++].ent = e;
+	}
+	*num_ents_p = num_ents;
+	return blame_list;
+}
+
+/*
+ * Reset the scanned status on all entries.
+ */
+static void reset_scanned_flag(struct scoreboard *sb)
+{
+	struct blame_entry *e;
+	for (e = sb->ent; e; e = e->next)
+		e->scanned = 0;
+}
+
+/*
+ * For lines target is suspected for, see if we can find code movement
+ * across file boundary from the parent commit.  porigin is the path
+ * in the parent we already tried.
+ */
+static int find_copy_in_parent(struct scoreboard *sb,
+			       struct origin *target,
+			       struct commit *parent,
+			       struct origin *porigin,
+			       int opt)
+{
+	struct diff_options diff_opts;
+	const char *paths[1];
+	int i, j;
+	int retval;
+	struct blame_list *blame_list;
+	int num_ents;
+
+	blame_list = setup_blame_list(sb, target, blame_copy_score, &num_ents);
+	if (!blame_list)
+		return 1; /* nothing remains for this target */
+
+	diff_setup(&diff_opts);
+	DIFF_OPT_SET(&diff_opts, RECURSIVE);
+	diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+
+	paths[0] = NULL;
+	diff_tree_setup_paths(paths, &diff_opts);
+	if (diff_setup_done(&diff_opts) < 0)
+		die("diff-setup");
+
+	/* Try "find copies harder" on new path if requested;
+	 * we do not want to use diffcore_rename() actually to
+	 * match things up; find_copies_harder is set only to
+	 * force diff_tree_sha1() to feed all filepairs to diff_queue,
+	 * and this code needs to be after diff_setup_done(), which
+	 * usually makes find-copies-harder imply copy detection.
+	 */
+	if ((opt & PICKAXE_BLAME_COPY_HARDEST)
+	    || ((opt & PICKAXE_BLAME_COPY_HARDER)
+		&& (!porigin || strcmp(target->path, porigin->path))))
+		DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
+
+	if (is_null_sha1(target->commit->object.sha1))
+		do_diff_cache(parent->tree->object.sha1, &diff_opts);
+	else
+		diff_tree_sha1(parent->tree->object.sha1,
+			       target->commit->tree->object.sha1,
+			       "", &diff_opts);
+
+	if (!DIFF_OPT_TST(&diff_opts, FIND_COPIES_HARDER))
+		diffcore_std(&diff_opts);
+
+	retval = 0;
+	while (1) {
+		int made_progress = 0;
+
+		for (i = 0; i < diff_queued_diff.nr; i++) {
+			struct diff_filepair *p = diff_queued_diff.queue[i];
+			struct origin *norigin;
+			mmfile_t file_p;
+			struct blame_entry this[3];
+
+			if (!DIFF_FILE_VALID(p->one))
+				continue; /* does not exist in parent */
+			if (S_ISGITLINK(p->one->mode))
+				continue; /* ignore git links */
+			if (porigin && !strcmp(p->one->path, porigin->path))
+				/* find_move already dealt with this path */
+				continue;
+
+			norigin = get_origin(sb, parent, p->one->path);
+			hashcpy(norigin->blob_sha1, p->one->sha1);
+			fill_origin_blob(norigin, &file_p);
+			if (!file_p.ptr)
+				continue;
+
+			for (j = 0; j < num_ents; j++) {
+				find_copy_in_blob(sb, blame_list[j].ent,
+						  norigin, this, &file_p);
+				copy_split_if_better(sb, blame_list[j].split,
+						     this);
+				decref_split(this);
+			}
+			origin_decref(norigin);
+		}
+
+		for (j = 0; j < num_ents; j++) {
+			struct blame_entry *split = blame_list[j].split;
+			if (split[1].suspect &&
+			    blame_copy_score < ent_score(sb, &split[1])) {
+				split_blame(sb, split, blame_list[j].ent);
+				made_progress = 1;
+			}
+			else
+				blame_list[j].ent->scanned = 1;
+			decref_split(split);
+		}
+		free(blame_list);
+
+		if (!made_progress)
+			break;
+		blame_list = setup_blame_list(sb, target, blame_copy_score, &num_ents);
+		if (!blame_list) {
+			retval = 1;
+			break;
+		}
+	}
+	reset_scanned_flag(sb);
+	diff_flush(&diff_opts);
+	diff_tree_release_paths(&diff_opts);
+	return retval;
+}
+
+/*
+ * The blobs of origin and porigin exactly match, so everything
+ * origin is suspected for can be blamed on the parent.
+ */
+static void pass_whole_blame(struct scoreboard *sb,
+			     struct origin *origin, struct origin *porigin)
+{
+	struct blame_entry *e;
+
+	if (!porigin->file.ptr && origin->file.ptr) {
+		/* Steal its file */
+		porigin->file = origin->file;
+		origin->file.ptr = NULL;
+	}
+	for (e = sb->ent; e; e = e->next) {
+		if (!same_suspect(e->suspect, origin))
+			continue;
+		origin_incref(porigin);
+		origin_decref(e->suspect);
+		e->suspect = porigin;
+	}
+}
+
+/*
+ * We pass blame from the current commit to its parents.  We keep saying
+ * "parent" (and "porigin"), but what we mean is to find scapegoat to
+ * exonerate ourselves.
+ */
+static struct commit_list *first_scapegoat(struct rev_info *revs, struct commit *commit)
+{
+	if (!reverse)
+		return commit->parents;
+	return lookup_decoration(&revs->children, &commit->object);
+}
+
+static int num_scapegoats(struct rev_info *revs, struct commit *commit)
+{
+	int cnt;
+	struct commit_list *l = first_scapegoat(revs, commit);
+	for (cnt = 0; l; l = l->next)
+		cnt++;
+	return cnt;
+}
+
+#define MAXSG 16
+
+static void pass_blame(struct scoreboard *sb, struct origin *origin, int opt)
+{
+	struct rev_info *revs = sb->revs;
+	int i, pass, num_sg;
+	struct commit *commit = origin->commit;
+	struct commit_list *sg;
+	struct origin *sg_buf[MAXSG];
+	struct origin *porigin, **sg_origin = sg_buf;
+
+	num_sg = num_scapegoats(revs, commit);
+	if (!num_sg)
+		goto finish;
+	else if (num_sg < ARRAY_SIZE(sg_buf))
+		memset(sg_buf, 0, sizeof(sg_buf));
+	else
+		sg_origin = xcalloc(num_sg, sizeof(*sg_origin));
+
+	/*
+	 * The first pass looks for unrenamed path to optimize for
+	 * common cases, then we look for renames in the second pass.
+	 */
+	for (pass = 0; pass < 2; pass++) {
+		struct origin *(*find)(struct scoreboard *,
+				       struct commit *, struct origin *);
+		find = pass ? find_rename : find_origin;
+
+		for (i = 0, sg = first_scapegoat(revs, commit);
+		     i < num_sg && sg;
+		     sg = sg->next, i++) {
+			struct commit *p = sg->item;
+			int j, same;
+
+			if (sg_origin[i])
+				continue;
+			if (parse_commit(p))
+				continue;
+			porigin = find(sb, p, origin);
+			if (!porigin)
+				continue;
+			if (!hashcmp(porigin->blob_sha1, origin->blob_sha1)) {
+				pass_whole_blame(sb, origin, porigin);
+				origin_decref(porigin);
+				goto finish;
+			}
+			for (j = same = 0; j < i; j++)
+				if (sg_origin[j] &&
+				    !hashcmp(sg_origin[j]->blob_sha1,
+					     porigin->blob_sha1)) {
+					same = 1;
+					break;
+				}
+			if (!same)
+				sg_origin[i] = porigin;
+			else
+				origin_decref(porigin);
+		}
+	}
+
+	num_commits++;
+	for (i = 0, sg = first_scapegoat(revs, commit);
+	     i < num_sg && sg;
+	     sg = sg->next, i++) {
+		struct origin *porigin = sg_origin[i];
+		if (!porigin)
+			continue;
+		if (!origin->previous) {
+			origin_incref(porigin);
+			origin->previous = porigin;
+		}
+		if (pass_blame_to_parent(sb, origin, porigin))
+			goto finish;
+	}
+
+	/*
+	 * Optionally find moves in parents' files.
+	 */
+	if (opt & PICKAXE_BLAME_MOVE)
+		for (i = 0, sg = first_scapegoat(revs, commit);
+		     i < num_sg && sg;
+		     sg = sg->next, i++) {
+			struct origin *porigin = sg_origin[i];
+			if (!porigin)
+				continue;
+			if (find_move_in_parent(sb, origin, porigin))
+				goto finish;
+		}
+
+	/*
+	 * Optionally find copies from parents' files.
+	 */
+	if (opt & PICKAXE_BLAME_COPY)
+		for (i = 0, sg = first_scapegoat(revs, commit);
+		     i < num_sg && sg;
+		     sg = sg->next, i++) {
+			struct origin *porigin = sg_origin[i];
+			if (find_copy_in_parent(sb, origin, sg->item,
+						porigin, opt))
+				goto finish;
+		}
+
+ finish:
+	for (i = 0; i < num_sg; i++) {
+		if (sg_origin[i]) {
+			drop_origin_blob(sg_origin[i]);
+			origin_decref(sg_origin[i]);
+		}
+	}
+	drop_origin_blob(origin);
+	if (sg_buf != sg_origin)
+		free(sg_origin);
+}
+
+/*
+ * Information on commits, used for output.
+ */
+struct commit_info
+{
+	const char *author;
+	const char *author_mail;
+	unsigned long author_time;
+	const char *author_tz;
+
+	/* filled only when asked for details */
+	const char *committer;
+	const char *committer_mail;
+	unsigned long committer_time;
+	const char *committer_tz;
+
+	const char *summary;
+};
+
+/*
+ * Parse author/committer line in the commit object buffer
+ */
+static void get_ac_line(const char *inbuf, const char *what,
+			int person_len, char *person,
+			int mail_len, char *mail,
+			unsigned long *time, const char **tz)
+{
+	int len, tzlen, maillen;
+	char *tmp, *endp, *timepos, *mailpos;
+
+	tmp = strstr(inbuf, what);
+	if (!tmp)
+		goto error_out;
+	tmp += strlen(what);
+	endp = strchr(tmp, '\n');
+	if (!endp)
+		len = strlen(tmp);
+	else
+		len = endp - tmp;
+	if (person_len <= len) {
+	error_out:
+		/* Ugh */
+		*tz = "(unknown)";
+		strcpy(person, *tz);
+		strcpy(mail, *tz);
+		*time = 0;
+		return;
+	}
+	memcpy(person, tmp, len);
+
+	tmp = person;
+	tmp += len;
+	*tmp = 0;
+	while (person < tmp && *tmp != ' ')
+		tmp--;
+	if (tmp <= person)
+		goto error_out;
+	*tz = tmp+1;
+	tzlen = (person+len)-(tmp+1);
+
+	*tmp = 0;
+	while (person < tmp && *tmp != ' ')
+		tmp--;
+	if (tmp <= person)
+		goto error_out;
+	*time = strtoul(tmp, NULL, 10);
+	timepos = tmp;
+
+	*tmp = 0;
+	while (person < tmp && *tmp != ' ')
+		tmp--;
+	if (tmp <= person)
+		return;
+	mailpos = tmp + 1;
+	*tmp = 0;
+	maillen = timepos - tmp;
+	memcpy(mail, mailpos, maillen);
+
+	if (!mailmap.nr)
+		return;
+
+	/*
+	 * mailmap expansion may make the name longer.
+	 * make room by pushing stuff down.
+	 */
+	tmp = person + person_len - (tzlen + 1);
+	memmove(tmp, *tz, tzlen);
+	tmp[tzlen] = 0;
+	*tz = tmp;
+
+	/*
+	 * Now, convert both name and e-mail using mailmap
+	 */
+	if (map_user(&mailmap, mail+1, mail_len-1, person, tmp-person-1)) {
+		/* Add a trailing '>' to email, since map_user returns plain emails
+		   Note: It already has '<', since we replace from mail+1 */
+		mailpos = memchr(mail, '\0', mail_len);
+		if (mailpos && mailpos-mail < mail_len - 1) {
+			*mailpos = '>';
+			*(mailpos+1) = '\0';
+		}
+	}
+}
+
+static void get_commit_info(struct commit *commit,
+			    struct commit_info *ret,
+			    int detailed)
+{
+	int len;
+	char *tmp, *endp, *reencoded, *message;
+	static char author_name[1024];
+	static char author_mail[1024];
+	static char committer_name[1024];
+	static char committer_mail[1024];
+	static char summary_buf[1024];
+
+	/*
+	 * We've operated without save_commit_buffer, so
+	 * we now need to populate them for output.
+	 */
+	if (!commit->buffer) {
+		enum object_type type;
+		unsigned long size;
+		commit->buffer =
+			read_sha1_file(commit->object.sha1, &type, &size);
+		if (!commit->buffer)
+			die("Cannot read commit %s",
+			    sha1_to_hex(commit->object.sha1));
+	}
+	reencoded = reencode_commit_message(commit, NULL);
+	message   = reencoded ? reencoded : commit->buffer;
+	ret->author = author_name;
+	ret->author_mail = author_mail;
+	get_ac_line(message, "\nauthor ",
+		    sizeof(author_name), author_name,
+		    sizeof(author_mail), author_mail,
+		    &ret->author_time, &ret->author_tz);
+
+	if (!detailed) {
+		free(reencoded);
+		return;
+	}
+
+	ret->committer = committer_name;
+	ret->committer_mail = committer_mail;
+	get_ac_line(message, "\ncommitter ",
+		    sizeof(committer_name), committer_name,
+		    sizeof(committer_mail), committer_mail,
+		    &ret->committer_time, &ret->committer_tz);
+
+	ret->summary = summary_buf;
+	tmp = strstr(message, "\n\n");
+	if (!tmp) {
+	error_out:
+		sprintf(summary_buf, "(%s)", sha1_to_hex(commit->object.sha1));
+		free(reencoded);
+		return;
+	}
+	tmp += 2;
+	endp = strchr(tmp, '\n');
+	if (!endp)
+		endp = tmp + strlen(tmp);
+	len = endp - tmp;
+	if (len >= sizeof(summary_buf) || len == 0)
+		goto error_out;
+	memcpy(summary_buf, tmp, len);
+	summary_buf[len] = 0;
+	free(reencoded);
+}
+
+/*
+ * To allow LF and other nonportable characters in pathnames,
+ * they are c-style quoted as needed.
+ */
+static void write_filename_info(const char *path)
+{
+	printf("filename ");
+	write_name_quoted(path, stdout, '\n');
+}
+
+/*
+ * Porcelain/Incremental format wants to show a lot of details per
+ * commit.  Instead of repeating this every line, emit it only once,
+ * the first time each commit appears in the output.
+ */
+static int emit_one_suspect_detail(struct origin *suspect)
+{
+	struct commit_info ci;
+
+	if (suspect->commit->object.flags & METAINFO_SHOWN)
+		return 0;
+
+	suspect->commit->object.flags |= METAINFO_SHOWN;
+	get_commit_info(suspect->commit, &ci, 1);
+	printf("author %s\n", ci.author);
+	printf("author-mail %s\n", ci.author_mail);
+	printf("author-time %lu\n", ci.author_time);
+	printf("author-tz %s\n", ci.author_tz);
+	printf("committer %s\n", ci.committer);
+	printf("committer-mail %s\n", ci.committer_mail);
+	printf("committer-time %lu\n", ci.committer_time);
+	printf("committer-tz %s\n", ci.committer_tz);
+	printf("summary %s\n", ci.summary);
+	if (suspect->commit->object.flags & UNINTERESTING)
+		printf("boundary\n");
+	if (suspect->previous) {
+		struct origin *prev = suspect->previous;
+		printf("previous %s ", sha1_to_hex(prev->commit->object.sha1));
+		write_name_quoted(prev->path, stdout, '\n');
+	}
+	return 1;
+}
+
+/*
+ * The blame_entry is found to be guilty for the range.  Mark it
+ * as such, and show it in incremental output.
+ */
+static void found_guilty_entry(struct blame_entry *ent)
+{
+	if (ent->guilty)
+		return;
+	ent->guilty = 1;
+	if (incremental) {
+		struct origin *suspect = ent->suspect;
+
+		printf("%s %d %d %d\n",
+		       sha1_to_hex(suspect->commit->object.sha1),
+		       ent->s_lno + 1, ent->lno + 1, ent->num_lines);
+		emit_one_suspect_detail(suspect);
+		write_filename_info(suspect->path);
+		maybe_flush_or_die(stdout, "stdout");
+	}
+}
+
+/*
+ * The main loop -- while the scoreboard has lines whose true origin
+ * is still unknown, pick one blame_entry, and allow its current
+ * suspect to pass blames to its parents.
+ */
+static void assign_blame(struct scoreboard *sb, int opt)
+{
+	struct rev_info *revs = sb->revs;
+
+	while (1) {
+		struct blame_entry *ent;
+		struct commit *commit;
+		struct origin *suspect = NULL;
+
+		/* find one suspect to break down */
+		for (ent = sb->ent; !suspect && ent; ent = ent->next)
+			if (!ent->guilty)
+				suspect = ent->suspect;
+		if (!suspect)
+			return; /* all done */
+
+		/*
+		 * We will use this suspect later in the loop,
+		 * so hold onto it in the meantime.
+		 */
+		origin_incref(suspect);
+		commit = suspect->commit;
+		if (!commit->object.parsed)
+			parse_commit(commit);
+		if (reverse ||
+		    (!(commit->object.flags & UNINTERESTING) &&
+		     !(revs->max_age != -1 && commit->date < revs->max_age)))
+			pass_blame(sb, suspect, opt);
+		else {
+			commit->object.flags |= UNINTERESTING;
+			if (commit->object.parsed)
+				mark_parents_uninteresting(commit);
+		}
+		/* treat root commit as boundary */
+		if (!commit->parents && !show_root)
+			commit->object.flags |= UNINTERESTING;
+
+		/* Take responsibility for the remaining entries */
+		for (ent = sb->ent; ent; ent = ent->next)
+			if (same_suspect(ent->suspect, suspect))
+				found_guilty_entry(ent);
+		origin_decref(suspect);
+
+		if (DEBUG) /* sanity */
+			sanity_check_refcnt(sb);
+	}
+}
+
+static const char *format_time(unsigned long time, const char *tz_str,
+			       int show_raw_time)
+{
+	static char time_buf[128];
+	const char *time_str;
+	int time_len;
+	int tz;
+
+	if (show_raw_time) {
+		sprintf(time_buf, "%lu %s", time, tz_str);
+	}
+	else {
+		tz = atoi(tz_str);
+		time_str = show_date(time, tz, blame_date_mode);
+		time_len = strlen(time_str);
+		memcpy(time_buf, time_str, time_len);
+		memset(time_buf + time_len, ' ', blame_date_width - time_len);
+	}
+	return time_buf;
+}
+
+#define OUTPUT_ANNOTATE_COMPAT	001
+#define OUTPUT_LONG_OBJECT_NAME	002
+#define OUTPUT_RAW_TIMESTAMP	004
+#define OUTPUT_PORCELAIN	010
+#define OUTPUT_SHOW_NAME	020
+#define OUTPUT_SHOW_NUMBER	040
+#define OUTPUT_SHOW_SCORE      0100
+#define OUTPUT_NO_AUTHOR       0200
+
+static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent)
+{
+	int cnt;
+	const char *cp;
+	struct origin *suspect = ent->suspect;
+	char hex[41];
+
+	strcpy(hex, sha1_to_hex(suspect->commit->object.sha1));
+	printf("%s%c%d %d %d\n",
+	       hex,
+	       ent->guilty ? ' ' : '*', // purely for debugging
+	       ent->s_lno + 1,
+	       ent->lno + 1,
+	       ent->num_lines);
+	if (emit_one_suspect_detail(suspect) ||
+	    (suspect->commit->object.flags & MORE_THAN_ONE_PATH))
+		write_filename_info(suspect->path);
+
+	cp = nth_line(sb, ent->lno);
+	for (cnt = 0; cnt < ent->num_lines; cnt++) {
+		char ch;
+		if (cnt)
+			printf("%s %d %d\n", hex,
+			       ent->s_lno + 1 + cnt,
+			       ent->lno + 1 + cnt);
+		putchar('\t');
+		do {
+			ch = *cp++;
+			putchar(ch);
+		} while (ch != '\n' &&
+			 cp < sb->final_buf + sb->final_buf_size);
+	}
+
+	if (sb->final_buf_size && cp[-1] != '\n')
+		putchar('\n');
+}
+
+static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
+{
+	int cnt;
+	const char *cp;
+	struct origin *suspect = ent->suspect;
+	struct commit_info ci;
+	char hex[41];
+	int show_raw_time = !!(opt & OUTPUT_RAW_TIMESTAMP);
+
+	get_commit_info(suspect->commit, &ci, 1);
+	strcpy(hex, sha1_to_hex(suspect->commit->object.sha1));
+
+	cp = nth_line(sb, ent->lno);
+	for (cnt = 0; cnt < ent->num_lines; cnt++) {
+		char ch;
+		int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? 40 : 8;
+
+		if (suspect->commit->object.flags & UNINTERESTING) {
+			if (blank_boundary)
+				memset(hex, ' ', length);
+			else if (!(opt & OUTPUT_ANNOTATE_COMPAT)) {
+				length--;
+				putchar('^');
+			}
+		}
+
+		printf("%.*s", length, hex);
+		if (opt & OUTPUT_ANNOTATE_COMPAT)
+			printf("\t(%10s\t%10s\t%d)", ci.author,
+			       format_time(ci.author_time, ci.author_tz,
+					   show_raw_time),
+			       ent->lno + 1 + cnt);
+		else {
+			if (opt & OUTPUT_SHOW_SCORE)
+				printf(" %*d %02d",
+				       max_score_digits, ent->score,
+				       ent->suspect->refcnt);
+			if (opt & OUTPUT_SHOW_NAME)
+				printf(" %-*.*s", longest_file, longest_file,
+				       suspect->path);
+			if (opt & OUTPUT_SHOW_NUMBER)
+				printf(" %*d", max_orig_digits,
+				       ent->s_lno + 1 + cnt);
+
+			if (!(opt & OUTPUT_NO_AUTHOR)) {
+				int pad = longest_author - utf8_strwidth(ci.author);
+				printf(" (%s%*s %10s",
+				       ci.author, pad, "",
+				       format_time(ci.author_time,
+						   ci.author_tz,
+						   show_raw_time));
+			}
+			printf(" %*d) ",
+			       max_digits, ent->lno + 1 + cnt);
+		}
+		do {
+			ch = *cp++;
+			putchar(ch);
+		} while (ch != '\n' &&
+			 cp < sb->final_buf + sb->final_buf_size);
+	}
+
+	if (sb->final_buf_size && cp[-1] != '\n')
+		putchar('\n');
+}
+
+static void output(struct scoreboard *sb, int option)
+{
+	struct blame_entry *ent;
+
+	if (option & OUTPUT_PORCELAIN) {
+		for (ent = sb->ent; ent; ent = ent->next) {
+			struct blame_entry *oth;
+			struct origin *suspect = ent->suspect;
+			struct commit *commit = suspect->commit;
+			if (commit->object.flags & MORE_THAN_ONE_PATH)
+				continue;
+			for (oth = ent->next; oth; oth = oth->next) {
+				if ((oth->suspect->commit != commit) ||
+				    !strcmp(oth->suspect->path, suspect->path))
+					continue;
+				commit->object.flags |= MORE_THAN_ONE_PATH;
+				break;
+			}
+		}
+	}
+
+	for (ent = sb->ent; ent; ent = ent->next) {
+		if (option & OUTPUT_PORCELAIN)
+			emit_porcelain(sb, ent);
+		else {
+			emit_other(sb, ent, option);
+		}
+	}
+}
+
+/*
+ * To allow quick access to the contents of nth line in the
+ * final image, prepare an index in the scoreboard.
+ */
+static int prepare_lines(struct scoreboard *sb)
+{
+	const char *buf = sb->final_buf;
+	unsigned long len = sb->final_buf_size;
+	int num = 0, incomplete = 0, bol = 1;
+
+	if (len && buf[len-1] != '\n')
+		incomplete++; /* incomplete line at the end */
+	while (len--) {
+		if (bol) {
+			sb->lineno = xrealloc(sb->lineno,
+					      sizeof(int *) * (num + 1));
+			sb->lineno[num] = buf - sb->final_buf;
+			bol = 0;
+		}
+		if (*buf++ == '\n') {
+			num++;
+			bol = 1;
+		}
+	}
+	sb->lineno = xrealloc(sb->lineno,
+			      sizeof(int *) * (num + incomplete + 1));
+	sb->lineno[num + incomplete] = buf - sb->final_buf;
+	sb->num_lines = num + incomplete;
+	return sb->num_lines;
+}
+
+/*
+ * Add phony grafts for use with -S; this is primarily to
+ * support git's cvsserver that wants to give a linear history
+ * to its clients.
+ */
+static int read_ancestry(const char *graft_file)
+{
+	FILE *fp = fopen(graft_file, "r");
+	char buf[1024];
+	if (!fp)
+		return -1;
+	while (fgets(buf, sizeof(buf), fp)) {
+		/* The format is just "Commit Parent1 Parent2 ...\n" */
+		int len = strlen(buf);
+		struct commit_graft *graft = read_graft_line(buf, len);
+		if (graft)
+			register_commit_graft(graft, 0);
+	}
+	fclose(fp);
+	return 0;
+}
+
+/*
+ * How many columns do we need to show line numbers in decimal?
+ */
+static int lineno_width(int lines)
+{
+	int i, width;
+
+	for (width = 1, i = 10; i <= lines + 1; width++)
+		i *= 10;
+	return width;
+}
+
+/*
+ * How many columns do we need to show line numbers, authors,
+ * and filenames?
+ */
+static void find_alignment(struct scoreboard *sb, int *option)
+{
+	int longest_src_lines = 0;
+	int longest_dst_lines = 0;
+	unsigned largest_score = 0;
+	struct blame_entry *e;
+
+	for (e = sb->ent; e; e = e->next) {
+		struct origin *suspect = e->suspect;
+		struct commit_info ci;
+		int num;
+
+		if (strcmp(suspect->path, sb->path))
+			*option |= OUTPUT_SHOW_NAME;
+		num = strlen(suspect->path);
+		if (longest_file < num)
+			longest_file = num;
+		if (!(suspect->commit->object.flags & METAINFO_SHOWN)) {
+			suspect->commit->object.flags |= METAINFO_SHOWN;
+			get_commit_info(suspect->commit, &ci, 1);
+			num = utf8_strwidth(ci.author);
+			if (longest_author < num)
+				longest_author = num;
+		}
+		num = e->s_lno + e->num_lines;
+		if (longest_src_lines < num)
+			longest_src_lines = num;
+		num = e->lno + e->num_lines;
+		if (longest_dst_lines < num)
+			longest_dst_lines = num;
+		if (largest_score < ent_score(sb, e))
+			largest_score = ent_score(sb, e);
+	}
+	max_orig_digits = lineno_width(longest_src_lines);
+	max_digits = lineno_width(longest_dst_lines);
+	max_score_digits = lineno_width(largest_score);
+}
+
+/*
+ * For debugging -- origin is refcounted, and this asserts that
+ * we do not underflow.
+ */
+static void sanity_check_refcnt(struct scoreboard *sb)
+{
+	int baa = 0;
+	struct blame_entry *ent;
+
+	for (ent = sb->ent; ent; ent = ent->next) {
+		/* Nobody should have zero or negative refcnt */
+		if (ent->suspect->refcnt <= 0) {
+			fprintf(stderr, "%s in %s has negative refcnt %d\n",
+				ent->suspect->path,
+				sha1_to_hex(ent->suspect->commit->object.sha1),
+				ent->suspect->refcnt);
+			baa = 1;
+		}
+	}
+	if (baa) {
+		int opt = 0160;
+		find_alignment(sb, &opt);
+		output(sb, opt);
+		die("Baa %d!", baa);
+	}
+}
+
+/*
+ * Used for the command line parsing; check if the path exists
+ * in the working tree.
+ */
+static int has_string_in_work_tree(const char *path)
+{
+	struct stat st;
+	return !lstat(path, &st);
+}
+
+static unsigned parse_score(const char *arg)
+{
+	char *end;
+	unsigned long score = strtoul(arg, &end, 10);
+	if (*end)
+		return 0;
+	return score;
+}
+
+static const char *add_prefix(const char *prefix, const char *path)
+{
+	return prefix_path(prefix, prefix ? strlen(prefix) : 0, path);
+}
+
+/*
+ * Parsing of (comma separated) one item in the -L option
+ */
+static const char *parse_loc(const char *spec,
+			     struct scoreboard *sb, long lno,
+			     long begin, long *ret)
+{
+	char *term;
+	const char *line;
+	long num;
+	int reg_error;
+	regex_t regexp;
+	regmatch_t match[1];
+
+	/* Allow "-L <something>,+20" to mean starting at <something>
+	 * for 20 lines, or "-L <something>,-5" for 5 lines ending at
+	 * <something>.
+	 */
+	if (1 < begin && (spec[0] == '+' || spec[0] == '-')) {
+		num = strtol(spec + 1, &term, 10);
+		if (term != spec + 1) {
+			if (spec[0] == '-')
+				num = 0 - num;
+			if (0 < num)
+				*ret = begin + num - 2;
+			else if (!num)
+				*ret = begin;
+			else
+				*ret = begin + num;
+			return term;
+		}
+		return spec;
+	}
+	num = strtol(spec, &term, 10);
+	if (term != spec) {
+		*ret = num;
+		return term;
+	}
+	if (spec[0] != '/')
+		return spec;
+
+	/* it could be a regexp of form /.../ */
+	for (term = (char *) spec + 1; *term && *term != '/'; term++) {
+		if (*term == '\\')
+			term++;
+	}
+	if (*term != '/')
+		return spec;
+
+	/* try [spec+1 .. term-1] as regexp */
+	*term = 0;
+	begin--; /* input is in human terms */
+	line = nth_line(sb, begin);
+
+	if (!(reg_error = regcomp(&regexp, spec + 1, REG_NEWLINE)) &&
+	    !(reg_error = regexec(&regexp, line, 1, match, 0))) {
+		const char *cp = line + match[0].rm_so;
+		const char *nline;
+
+		while (begin++ < lno) {
+			nline = nth_line(sb, begin);
+			if (line <= cp && cp < nline)
+				break;
+			line = nline;
+		}
+		*ret = begin;
+		regfree(&regexp);
+		*term++ = '/';
+		return term;
+	}
+	else {
+		char errbuf[1024];
+		regerror(reg_error, &regexp, errbuf, 1024);
+		die("-L parameter '%s': %s", spec + 1, errbuf);
+	}
+}
+
+/*
+ * Parsing of -L option
+ */
+static void prepare_blame_range(struct scoreboard *sb,
+				const char *bottomtop,
+				long lno,
+				long *bottom, long *top)
+{
+	const char *term;
+
+	term = parse_loc(bottomtop, sb, lno, 1, bottom);
+	if (*term == ',') {
+		term = parse_loc(term + 1, sb, lno, *bottom + 1, top);
+		if (*term)
+			usage(blame_usage);
+	}
+	if (*term)
+		usage(blame_usage);
+}
+
+static int git_blame_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "blame.showroot")) {
+		show_root = git_config_bool(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "blame.blankboundary")) {
+		blank_boundary = git_config_bool(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "blame.date")) {
+		if (!value)
+			return config_error_nonbool(var);
+		blame_date_mode = parse_date_format(value);
+		return 0;
+	}
+	return git_default_config(var, value, cb);
+}
+
+/*
+ * Prepare a dummy commit that represents the work tree (or staged) item.
+ * Note that annotating work tree item never works in the reverse.
+ */
+static struct commit *fake_working_tree_commit(const char *path, const char *contents_from)
+{
+	struct commit *commit;
+	struct origin *origin;
+	unsigned char head_sha1[20];
+	struct strbuf buf = STRBUF_INIT;
+	const char *ident;
+	time_t now;
+	int size, len;
+	struct cache_entry *ce;
+	unsigned mode;
+
+	if (get_sha1("HEAD", head_sha1))
+		die("No such ref: HEAD");
+
+	time(&now);
+	commit = xcalloc(1, sizeof(*commit));
+	commit->parents = xcalloc(1, sizeof(*commit->parents));
+	commit->parents->item = lookup_commit_reference(head_sha1);
+	commit->object.parsed = 1;
+	commit->date = now;
+	commit->object.type = OBJ_COMMIT;
+
+	origin = make_origin(commit, path);
+
+	if (!contents_from || strcmp("-", contents_from)) {
+		struct stat st;
+		const char *read_from;
+
+		if (contents_from) {
+			if (stat(contents_from, &st) < 0)
+				die_errno("Cannot stat '%s'", contents_from);
+			read_from = contents_from;
+		}
+		else {
+			if (lstat(path, &st) < 0)
+				die_errno("Cannot lstat '%s'", path);
+			read_from = path;
+		}
+		mode = canon_mode(st.st_mode);
+		switch (st.st_mode & S_IFMT) {
+		case S_IFREG:
+			if (strbuf_read_file(&buf, read_from, st.st_size) != st.st_size)
+				die_errno("cannot open or read '%s'", read_from);
+			break;
+		case S_IFLNK:
+			if (strbuf_readlink(&buf, read_from, st.st_size) < 0)
+				die_errno("cannot readlink '%s'", read_from);
+			break;
+		default:
+			die("unsupported file type %s", read_from);
+		}
+	}
+	else {
+		/* Reading from stdin */
+		contents_from = "standard input";
+		mode = 0;
+		if (strbuf_read(&buf, 0, 0) < 0)
+			die_errno("failed to read from stdin");
+	}
+	convert_to_git(path, buf.buf, buf.len, &buf, 0);
+	origin->file.ptr = buf.buf;
+	origin->file.size = buf.len;
+	pretend_sha1_file(buf.buf, buf.len, OBJ_BLOB, origin->blob_sha1);
+	commit->util = origin;
+
+	/*
+	 * Read the current index, replace the path entry with
+	 * origin->blob_sha1 without mucking with its mode or type
+	 * bits; we are not going to write this index out -- we just
+	 * want to run "diff-index --cached".
+	 */
+	discard_cache();
+	read_cache();
+
+	len = strlen(path);
+	if (!mode) {
+		int pos = cache_name_pos(path, len);
+		if (0 <= pos)
+			mode = active_cache[pos]->ce_mode;
+		else
+			/* Let's not bother reading from HEAD tree */
+			mode = S_IFREG | 0644;
+	}
+	size = cache_entry_size(len);
+	ce = xcalloc(1, size);
+	hashcpy(ce->sha1, origin->blob_sha1);
+	memcpy(ce->name, path, len);
+	ce->ce_flags = create_ce_flags(len, 0);
+	ce->ce_mode = create_ce_mode(mode);
+	add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
+
+	/*
+	 * We are not going to write this out, so this does not matter
+	 * right now, but someday we might optimize diff-index --cached
+	 * with cache-tree information.
+	 */
+	cache_tree_invalidate_path(active_cache_tree, path);
+
+	commit->buffer = xmalloc(400);
+	ident = fmt_ident("Not Committed Yet", "not.committed.yet", NULL, 0);
+	snprintf(commit->buffer, 400,
+		"tree 0000000000000000000000000000000000000000\n"
+		"parent %s\n"
+		"author %s\n"
+		"committer %s\n\n"
+		"Version of %s from %s\n",
+		sha1_to_hex(head_sha1),
+		ident, ident, path, contents_from ? contents_from : path);
+	return commit;
+}
+
+static const char *prepare_final(struct scoreboard *sb)
+{
+	int i;
+	const char *final_commit_name = NULL;
+	struct rev_info *revs = sb->revs;
+
+	/*
+	 * There must be one and only one positive commit in the
+	 * revs->pending array.
+	 */
+	for (i = 0; i < revs->pending.nr; i++) {
+		struct object *obj = revs->pending.objects[i].item;
+		if (obj->flags & UNINTERESTING)
+			continue;
+		while (obj->type == OBJ_TAG)
+			obj = deref_tag(obj, NULL, 0);
+		if (obj->type != OBJ_COMMIT)
+			die("Non commit %s?", revs->pending.objects[i].name);
+		if (sb->final)
+			die("More than one commit to dig from %s and %s?",
+			    revs->pending.objects[i].name,
+			    final_commit_name);
+		sb->final = (struct commit *) obj;
+		final_commit_name = revs->pending.objects[i].name;
+	}
+	return final_commit_name;
+}
+
+static const char *prepare_initial(struct scoreboard *sb)
+{
+	int i;
+	const char *final_commit_name = NULL;
+	struct rev_info *revs = sb->revs;
+
+	/*
+	 * There must be one and only one negative commit, and it must be
+	 * the boundary.
+	 */
+	for (i = 0; i < revs->pending.nr; i++) {
+		struct object *obj = revs->pending.objects[i].item;
+		if (!(obj->flags & UNINTERESTING))
+			continue;
+		while (obj->type == OBJ_TAG)
+			obj = deref_tag(obj, NULL, 0);
+		if (obj->type != OBJ_COMMIT)
+			die("Non commit %s?", revs->pending.objects[i].name);
+		if (sb->final)
+			die("More than one commit to dig down to %s and %s?",
+			    revs->pending.objects[i].name,
+			    final_commit_name);
+		sb->final = (struct commit *) obj;
+		final_commit_name = revs->pending.objects[i].name;
+	}
+	if (!final_commit_name)
+		die("No commit to dig down to?");
+	return final_commit_name;
+}
+
+static int blame_copy_callback(const struct option *option, const char *arg, int unset)
+{
+	int *opt = option->value;
+
+	/*
+	 * -C enables copy from removed files;
+	 * -C -C enables copy from existing files, but only
+	 *       when blaming a new file;
+	 * -C -C -C enables copy from existing files for
+	 *          everybody
+	 */
+	if (*opt & PICKAXE_BLAME_COPY_HARDER)
+		*opt |= PICKAXE_BLAME_COPY_HARDEST;
+	if (*opt & PICKAXE_BLAME_COPY)
+		*opt |= PICKAXE_BLAME_COPY_HARDER;
+	*opt |= PICKAXE_BLAME_COPY | PICKAXE_BLAME_MOVE;
+
+	if (arg)
+		blame_copy_score = parse_score(arg);
+	return 0;
+}
+
+static int blame_move_callback(const struct option *option, const char *arg, int unset)
+{
+	int *opt = option->value;
+
+	*opt |= PICKAXE_BLAME_MOVE;
+
+	if (arg)
+		blame_move_score = parse_score(arg);
+	return 0;
+}
+
+static int blame_bottomtop_callback(const struct option *option, const char *arg, int unset)
+{
+	const char **bottomtop = option->value;
+	if (!arg)
+		return -1;
+	if (*bottomtop)
+		die("More than one '-L n,m' option given");
+	*bottomtop = arg;
+	return 0;
+}
+
+int cmd_blame(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info revs;
+	const char *path;
+	struct scoreboard sb;
+	struct origin *o;
+	struct blame_entry *ent;
+	long dashdash_pos, bottom, top, lno;
+	const char *final_commit_name = NULL;
+	enum object_type type;
+
+	static const char *bottomtop = NULL;
+	static int output_option = 0, opt = 0;
+	static int show_stats = 0;
+	static const char *revs_file = NULL;
+	static const char *contents_from = NULL;
+	static const struct option options[] = {
+		OPT_BOOLEAN(0, "incremental", &incremental, "Show blame entries as we find them, incrementally"),
+		OPT_BOOLEAN('b', NULL, &blank_boundary, "Show blank SHA-1 for boundary commits (Default: off)"),
+		OPT_BOOLEAN(0, "root", &show_root, "Do not treat root commits as boundaries (Default: off)"),
+		OPT_BOOLEAN(0, "show-stats", &show_stats, "Show work cost statistics"),
+		OPT_BIT(0, "score-debug", &output_option, "Show output score for blame entries", OUTPUT_SHOW_SCORE),
+		OPT_BIT('f', "show-name", &output_option, "Show original filename (Default: auto)", OUTPUT_SHOW_NAME),
+		OPT_BIT('n', "show-number", &output_option, "Show original linenumber (Default: off)", OUTPUT_SHOW_NUMBER),
+		OPT_BIT('p', "porcelain", &output_option, "Show in a format designed for machine consumption", OUTPUT_PORCELAIN),
+		OPT_BIT('c', NULL, &output_option, "Use the same output mode as git-annotate (Default: off)", OUTPUT_ANNOTATE_COMPAT),
+		OPT_BIT('t', NULL, &output_option, "Show raw timestamp (Default: off)", OUTPUT_RAW_TIMESTAMP),
+		OPT_BIT('l', NULL, &output_option, "Show long commit SHA1 (Default: off)", OUTPUT_LONG_OBJECT_NAME),
+		OPT_BIT('s', NULL, &output_option, "Suppress author name and timestamp (Default: off)", OUTPUT_NO_AUTHOR),
+		OPT_BIT('w', NULL, &xdl_opts, "Ignore whitespace differences", XDF_IGNORE_WHITESPACE),
+		OPT_STRING('S', NULL, &revs_file, "file", "Use revisions from <file> instead of calling git-rev-list"),
+		OPT_STRING(0, "contents", &contents_from, "file", "Use <file>'s contents as the final image"),
+		{ OPTION_CALLBACK, 'C', NULL, &opt, "score", "Find line copies within and across files", PARSE_OPT_OPTARG, blame_copy_callback },
+		{ OPTION_CALLBACK, 'M', NULL, &opt, "score", "Find line movements within and across files", PARSE_OPT_OPTARG, blame_move_callback },
+		OPT_CALLBACK('L', NULL, &bottomtop, "n,m", "Process only line range n,m, counting from 1", blame_bottomtop_callback),
+		OPT_END()
+	};
+
+	struct parse_opt_ctx_t ctx;
+	int cmd_is_annotate = !strcmp(argv[0], "annotate");
+
+	git_config(git_blame_config, NULL);
+	init_revisions(&revs, NULL);
+	revs.date_mode = blame_date_mode;
+
+	save_commit_buffer = 0;
+	dashdash_pos = 0;
+
+	parse_options_start(&ctx, argc, argv, prefix, PARSE_OPT_KEEP_DASHDASH |
+			    PARSE_OPT_KEEP_ARGV0);
+	for (;;) {
+		switch (parse_options_step(&ctx, options, blame_opt_usage)) {
+		case PARSE_OPT_HELP:
+			exit(129);
+		case PARSE_OPT_DONE:
+			if (ctx.argv[0])
+				dashdash_pos = ctx.cpidx;
+			goto parse_done;
+		}
+
+		if (!strcmp(ctx.argv[0], "--reverse")) {
+			ctx.argv[0] = "--children";
+			reverse = 1;
+		}
+		parse_revision_opt(&revs, &ctx, options, blame_opt_usage);
+	}
+parse_done:
+	argc = parse_options_end(&ctx);
+
+	if (revs_file && read_ancestry(revs_file))
+		die_errno("reading graft file '%s' failed", revs_file);
+
+	if (cmd_is_annotate) {
+		output_option |= OUTPUT_ANNOTATE_COMPAT;
+		blame_date_mode = DATE_ISO8601;
+	} else {
+		blame_date_mode = revs.date_mode;
+	}
+
+	/* The maximum width used to show the dates */
+	switch (blame_date_mode) {
+	case DATE_RFC2822:
+		blame_date_width = sizeof("Thu, 19 Oct 2006 16:00:04 -0700");
+		break;
+	case DATE_ISO8601:
+		blame_date_width = sizeof("2006-10-19 16:00:04 -0700");
+		break;
+	case DATE_RAW:
+		blame_date_width = sizeof("1161298804 -0700");
+		break;
+	case DATE_SHORT:
+		blame_date_width = sizeof("2006-10-19");
+		break;
+	case DATE_RELATIVE:
+		/* "normal" is used as the fallback for "relative" */
+	case DATE_LOCAL:
+	case DATE_NORMAL:
+		blame_date_width = sizeof("Thu Oct 19 16:00:04 2006 -0700");
+		break;
+	}
+	blame_date_width -= 1; /* strip the null */
+
+	if (DIFF_OPT_TST(&revs.diffopt, FIND_COPIES_HARDER))
+		opt |= (PICKAXE_BLAME_COPY | PICKAXE_BLAME_MOVE |
+			PICKAXE_BLAME_COPY_HARDER);
+
+	if (!blame_move_score)
+		blame_move_score = BLAME_DEFAULT_MOVE_SCORE;
+	if (!blame_copy_score)
+		blame_copy_score = BLAME_DEFAULT_COPY_SCORE;
+
+	/*
+	 * We have collected options unknown to us in argv[1..unk]
+	 * which are to be passed to revision machinery if we are
+	 * going to do the "bottom" processing.
+	 *
+	 * The remaining are:
+	 *
+	 * (1) if dashdash_pos != 0, its either
+	 *     "blame [revisions] -- <path>" or
+	 *     "blame -- <path> <rev>"
+	 *
+	 * (2) otherwise, its one of the two:
+	 *     "blame [revisions] <path>"
+	 *     "blame <path> <rev>"
+	 *
+	 * Note that we must strip out <path> from the arguments: we do not
+	 * want the path pruning but we may want "bottom" processing.
+	 */
+	if (dashdash_pos) {
+		switch (argc - dashdash_pos - 1) {
+		case 2: /* (1b) */
+			if (argc != 4)
+				usage_with_options(blame_opt_usage, options);
+			/* reorder for the new way: <rev> -- <path> */
+			argv[1] = argv[3];
+			argv[3] = argv[2];
+			argv[2] = "--";
+			/* FALLTHROUGH */
+		case 1: /* (1a) */
+			path = add_prefix(prefix, argv[--argc]);
+			argv[argc] = NULL;
+			break;
+		default:
+			usage_with_options(blame_opt_usage, options);
+		}
+	} else {
+		if (argc < 2)
+			usage_with_options(blame_opt_usage, options);
+		path = add_prefix(prefix, argv[argc - 1]);
+		if (argc == 3 && !has_string_in_work_tree(path)) { /* (2b) */
+			path = add_prefix(prefix, argv[1]);
+			argv[1] = argv[2];
+		}
+		argv[argc - 1] = "--";
+
+		setup_work_tree();
+		if (!has_string_in_work_tree(path))
+			die_errno("cannot stat path '%s'", path);
+	}
+
+	revs.disable_stdin = 1;
+	setup_revisions(argc, argv, &revs, NULL);
+	memset(&sb, 0, sizeof(sb));
+
+	sb.revs = &revs;
+	if (!reverse)
+		final_commit_name = prepare_final(&sb);
+	else if (contents_from)
+		die("--contents and --children do not blend well.");
+	else
+		final_commit_name = prepare_initial(&sb);
+
+	if (!sb.final) {
+		/*
+		 * "--not A B -- path" without anything positive;
+		 * do not default to HEAD, but use the working tree
+		 * or "--contents".
+		 */
+		setup_work_tree();
+		sb.final = fake_working_tree_commit(path, contents_from);
+		add_pending_object(&revs, &(sb.final->object), ":");
+	}
+	else if (contents_from)
+		die("Cannot use --contents with final commit object name");
+
+	/*
+	 * If we have bottom, this will mark the ancestors of the
+	 * bottom commits we would reach while traversing as
+	 * uninteresting.
+	 */
+	if (prepare_revision_walk(&revs))
+		die("revision walk setup failed");
+
+	if (is_null_sha1(sb.final->object.sha1)) {
+		char *buf;
+		o = sb.final->util;
+		buf = xmalloc(o->file.size + 1);
+		memcpy(buf, o->file.ptr, o->file.size + 1);
+		sb.final_buf = buf;
+		sb.final_buf_size = o->file.size;
+	}
+	else {
+		o = get_origin(&sb, sb.final, path);
+		if (fill_blob_sha1(o))
+			die("no such path %s in %s", path, final_commit_name);
+
+		sb.final_buf = read_sha1_file(o->blob_sha1, &type,
+					      &sb.final_buf_size);
+		if (!sb.final_buf)
+			die("Cannot read blob %s for path %s",
+			    sha1_to_hex(o->blob_sha1),
+			    path);
+	}
+	num_read_blob++;
+	lno = prepare_lines(&sb);
+
+	bottom = top = 0;
+	if (bottomtop)
+		prepare_blame_range(&sb, bottomtop, lno, &bottom, &top);
+	if (bottom && top && top < bottom) {
+		long tmp;
+		tmp = top; top = bottom; bottom = tmp;
+	}
+	if (bottom < 1)
+		bottom = 1;
+	if (top < 1)
+		top = lno;
+	bottom--;
+	if (lno < top || lno < bottom)
+		die("file %s has only %lu lines", path, lno);
+
+	ent = xcalloc(1, sizeof(*ent));
+	ent->lno = bottom;
+	ent->num_lines = top - bottom;
+	ent->suspect = o;
+	ent->s_lno = bottom;
+
+	sb.ent = ent;
+	sb.path = path;
+
+	read_mailmap(&mailmap, NULL);
+
+	if (!incremental)
+		setup_pager();
+
+	assign_blame(&sb, opt);
+
+	if (incremental)
+		return 0;
+
+	coalesce(&sb);
+
+	if (!(output_option & OUTPUT_PORCELAIN))
+		find_alignment(&sb, &output_option);
+
+	output(&sb, output_option);
+	free((void *)sb.final_buf);
+	for (ent = sb.ent; ent; ) {
+		struct blame_entry *e = ent->next;
+		free(ent);
+		ent = e;
+	}
+
+	if (show_stats) {
+		printf("num read blob: %d\n", num_read_blob);
+		printf("num get patch: %d\n", num_get_patch);
+		printf("num commits: %d\n", num_commits);
+	}
+	return 0;
+}
diff --git a/builtin/branch.c b/builtin/branch.c
new file mode 100644
index 0000000..6cf7e72
--- /dev/null
+++ b/builtin/branch.c
@@ -0,0 +1,696 @@
+/*
+ * Builtin "git branch"
+ *
+ * Copyright (c) 2006 Kristian Høgsberg <krh@redhat.com>
+ * Based on git-branch.sh by Junio C Hamano.
+ */
+
+#include "cache.h"
+#include "color.h"
+#include "refs.h"
+#include "commit.h"
+#include "builtin.h"
+#include "remote.h"
+#include "parse-options.h"
+#include "branch.h"
+#include "diff.h"
+#include "revision.h"
+
+static const char * const builtin_branch_usage[] = {
+	"git branch [options] [-r | -a] [--merged | --no-merged]",
+	"git branch [options] [-l] [-f] <branchname> [<start-point>]",
+	"git branch [options] [-r] (-d | -D) <branchname>",
+	"git branch [options] (-m | -M) [<oldbranch>] <newbranch>",
+	NULL
+};
+
+#define REF_LOCAL_BRANCH    0x01
+#define REF_REMOTE_BRANCH   0x02
+
+static const char *head;
+static unsigned char head_sha1[20];
+
+static int branch_use_color = -1;
+static char branch_colors[][COLOR_MAXLEN] = {
+	GIT_COLOR_RESET,
+	GIT_COLOR_NORMAL,	/* PLAIN */
+	GIT_COLOR_RED,		/* REMOTE */
+	GIT_COLOR_NORMAL,	/* LOCAL */
+	GIT_COLOR_GREEN,	/* CURRENT */
+};
+enum color_branch {
+	BRANCH_COLOR_RESET = 0,
+	BRANCH_COLOR_PLAIN = 1,
+	BRANCH_COLOR_REMOTE = 2,
+	BRANCH_COLOR_LOCAL = 3,
+	BRANCH_COLOR_CURRENT = 4,
+};
+
+static enum merge_filter {
+	NO_FILTER = 0,
+	SHOW_NOT_MERGED,
+	SHOW_MERGED,
+} merge_filter;
+static unsigned char merge_filter_ref[20];
+
+static int parse_branch_color_slot(const char *var, int ofs)
+{
+	if (!strcasecmp(var+ofs, "plain"))
+		return BRANCH_COLOR_PLAIN;
+	if (!strcasecmp(var+ofs, "reset"))
+		return BRANCH_COLOR_RESET;
+	if (!strcasecmp(var+ofs, "remote"))
+		return BRANCH_COLOR_REMOTE;
+	if (!strcasecmp(var+ofs, "local"))
+		return BRANCH_COLOR_LOCAL;
+	if (!strcasecmp(var+ofs, "current"))
+		return BRANCH_COLOR_CURRENT;
+	return -1;
+}
+
+static int git_branch_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "color.branch")) {
+		branch_use_color = git_config_colorbool(var, value, -1);
+		return 0;
+	}
+	if (!prefixcmp(var, "color.branch.")) {
+		int slot = parse_branch_color_slot(var, 13);
+		if (slot < 0)
+			return 0;
+		if (!value)
+			return config_error_nonbool(var);
+		color_parse(value, var, branch_colors[slot]);
+		return 0;
+	}
+	return git_color_default_config(var, value, cb);
+}
+
+static const char *branch_get_color(enum color_branch ix)
+{
+	if (branch_use_color > 0)
+		return branch_colors[ix];
+	return "";
+}
+
+static int branch_merged(int kind, const char *name,
+			 struct commit *rev, struct commit *head_rev)
+{
+	/*
+	 * This checks whether the merge bases of branch and HEAD (or
+	 * the other branch this branch builds upon) contains the
+	 * branch, which means that the branch has already been merged
+	 * safely to HEAD (or the other branch).
+	 */
+	struct commit *reference_rev = NULL;
+	const char *reference_name = NULL;
+	int merged;
+
+	if (kind == REF_LOCAL_BRANCH) {
+		struct branch *branch = branch_get(name);
+		unsigned char sha1[20];
+
+		if (branch &&
+		    branch->merge &&
+		    branch->merge[0] &&
+		    branch->merge[0]->dst &&
+		    (reference_name =
+		     resolve_ref(branch->merge[0]->dst, sha1, 1, NULL)) != NULL)
+			reference_rev = lookup_commit_reference(sha1);
+	}
+	if (!reference_rev)
+		reference_rev = head_rev;
+
+	merged = in_merge_bases(rev, &reference_rev, 1);
+
+	/*
+	 * After the safety valve is fully redefined to "check with
+	 * upstream, if any, otherwise with HEAD", we should just
+	 * return the result of the in_merge_bases() above without
+	 * any of the following code, but during the transition period,
+	 * a gentle reminder is in order.
+	 */
+	if ((head_rev != reference_rev) &&
+	    in_merge_bases(rev, &head_rev, 1) != merged) {
+		if (merged)
+			warning("deleting branch '%s' that has been merged to\n"
+				"         '%s', but it is not yet merged to HEAD.",
+				name, reference_name);
+		else
+			warning("not deleting branch '%s' that is not yet merged to\n"
+				"         '%s', even though it is merged to HEAD.",
+				name, reference_name);
+	}
+	return merged;
+}
+
+static int delete_branches(int argc, const char **argv, int force, int kinds)
+{
+	struct commit *rev, *head_rev = NULL;
+	unsigned char sha1[20];
+	char *name = NULL;
+	const char *fmt, *remote;
+	int i;
+	int ret = 0;
+	struct strbuf bname = STRBUF_INIT;
+
+	switch (kinds) {
+	case REF_REMOTE_BRANCH:
+		fmt = "refs/remotes/%s";
+		remote = "remote ";
+		force = 1;
+		break;
+	case REF_LOCAL_BRANCH:
+		fmt = "refs/heads/%s";
+		remote = "";
+		break;
+	default:
+		die("cannot use -a with -d");
+	}
+
+	if (!force) {
+		head_rev = lookup_commit_reference(head_sha1);
+		if (!head_rev)
+			die("Couldn't look up commit object for HEAD");
+	}
+	for (i = 0; i < argc; i++, strbuf_release(&bname)) {
+		strbuf_branchname(&bname, argv[i]);
+		if (kinds == REF_LOCAL_BRANCH && !strcmp(head, bname.buf)) {
+			error("Cannot delete the branch '%s' "
+			      "which you are currently on.", bname.buf);
+			ret = 1;
+			continue;
+		}
+
+		free(name);
+
+		name = xstrdup(mkpath(fmt, bname.buf));
+		if (!resolve_ref(name, sha1, 1, NULL)) {
+			error("%sbranch '%s' not found.",
+					remote, bname.buf);
+			ret = 1;
+			continue;
+		}
+
+		rev = lookup_commit_reference(sha1);
+		if (!rev) {
+			error("Couldn't look up commit object for '%s'", name);
+			ret = 1;
+			continue;
+		}
+
+		if (!force && !branch_merged(kinds, bname.buf, rev, head_rev)) {
+			error("The branch '%s' is not fully merged.\n"
+			      "If you are sure you want to delete it, "
+			      "run 'git branch -D %s'.", bname.buf, bname.buf);
+			ret = 1;
+			continue;
+		}
+
+		if (delete_ref(name, sha1, 0)) {
+			error("Error deleting %sbranch '%s'", remote,
+			      bname.buf);
+			ret = 1;
+		} else {
+			struct strbuf buf = STRBUF_INIT;
+			printf("Deleted %sbranch %s (was %s).\n", remote,
+			       bname.buf,
+			       find_unique_abbrev(sha1, DEFAULT_ABBREV));
+			strbuf_addf(&buf, "branch.%s", bname.buf);
+			if (git_config_rename_section(buf.buf, NULL) < 0)
+				warning("Update of config-file failed");
+			strbuf_release(&buf);
+		}
+	}
+
+	free(name);
+
+	return(ret);
+}
+
+struct ref_item {
+	char *name;
+	char *dest;
+	unsigned int kind, len;
+	struct commit *commit;
+};
+
+struct ref_list {
+	struct rev_info revs;
+	int index, alloc, maxwidth, verbose, abbrev;
+	struct ref_item *list;
+	struct commit_list *with_commit;
+	int kinds;
+};
+
+static char *resolve_symref(const char *src, const char *prefix)
+{
+	unsigned char sha1[20];
+	int flag;
+	const char *dst, *cp;
+
+	dst = resolve_ref(src, sha1, 0, &flag);
+	if (!(dst && (flag & REF_ISSYMREF)))
+		return NULL;
+	if (prefix && (cp = skip_prefix(dst, prefix)))
+		dst = cp;
+	return xstrdup(dst);
+}
+
+static int append_ref(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
+{
+	struct ref_list *ref_list = (struct ref_list*)(cb_data);
+	struct ref_item *newitem;
+	struct commit *commit;
+	int kind, i;
+	const char *prefix, *orig_refname = refname;
+
+	static struct {
+		int kind;
+		const char *prefix;
+		int pfxlen;
+	} ref_kind[] = {
+		{ REF_LOCAL_BRANCH, "refs/heads/", 11 },
+		{ REF_REMOTE_BRANCH, "refs/remotes/", 13 },
+	};
+
+	/* Detect kind */
+	for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
+		prefix = ref_kind[i].prefix;
+		if (strncmp(refname, prefix, ref_kind[i].pfxlen))
+			continue;
+		kind = ref_kind[i].kind;
+		refname += ref_kind[i].pfxlen;
+		break;
+	}
+	if (ARRAY_SIZE(ref_kind) <= i)
+		return 0;
+
+	/* Don't add types the caller doesn't want */
+	if ((kind & ref_list->kinds) == 0)
+		return 0;
+
+	commit = NULL;
+	if (ref_list->verbose || ref_list->with_commit || merge_filter != NO_FILTER) {
+		commit = lookup_commit_reference_gently(sha1, 1);
+		if (!commit)
+			return error("branch '%s' does not point at a commit", refname);
+
+		/* Filter with with_commit if specified */
+		if (!is_descendant_of(commit, ref_list->with_commit))
+			return 0;
+
+		if (merge_filter != NO_FILTER)
+			add_pending_object(&ref_list->revs,
+					   (struct object *)commit, refname);
+	}
+
+	/* Resize buffer */
+	if (ref_list->index >= ref_list->alloc) {
+		ref_list->alloc = alloc_nr(ref_list->alloc);
+		ref_list->list = xrealloc(ref_list->list,
+				ref_list->alloc * sizeof(struct ref_item));
+	}
+
+	/* Record the new item */
+	newitem = &(ref_list->list[ref_list->index++]);
+	newitem->name = xstrdup(refname);
+	newitem->kind = kind;
+	newitem->commit = commit;
+	newitem->len = strlen(refname);
+	newitem->dest = resolve_symref(orig_refname, prefix);
+	/* adjust for "remotes/" */
+	if (newitem->kind == REF_REMOTE_BRANCH &&
+	    ref_list->kinds != REF_REMOTE_BRANCH)
+		newitem->len += 8;
+	if (newitem->len > ref_list->maxwidth)
+		ref_list->maxwidth = newitem->len;
+
+	return 0;
+}
+
+static void free_ref_list(struct ref_list *ref_list)
+{
+	int i;
+
+	for (i = 0; i < ref_list->index; i++) {
+		free(ref_list->list[i].name);
+		free(ref_list->list[i].dest);
+	}
+	free(ref_list->list);
+}
+
+static int ref_cmp(const void *r1, const void *r2)
+{
+	struct ref_item *c1 = (struct ref_item *)(r1);
+	struct ref_item *c2 = (struct ref_item *)(r2);
+
+	if (c1->kind != c2->kind)
+		return c1->kind - c2->kind;
+	return strcmp(c1->name, c2->name);
+}
+
+static void fill_tracking_info(struct strbuf *stat, const char *branch_name,
+		int show_upstream_ref)
+{
+	int ours, theirs;
+	struct branch *branch = branch_get(branch_name);
+
+	if (!stat_tracking_info(branch, &ours, &theirs)) {
+		if (branch && branch->merge && branch->merge[0]->dst &&
+		    show_upstream_ref)
+			strbuf_addf(stat, "[%s] ",
+			    shorten_unambiguous_ref(branch->merge[0]->dst, 0));
+		return;
+	}
+
+	strbuf_addch(stat, '[');
+	if (show_upstream_ref)
+		strbuf_addf(stat, "%s: ",
+			shorten_unambiguous_ref(branch->merge[0]->dst, 0));
+	if (!ours)
+		strbuf_addf(stat, "behind %d] ", theirs);
+	else if (!theirs)
+		strbuf_addf(stat, "ahead %d] ", ours);
+	else
+		strbuf_addf(stat, "ahead %d, behind %d] ", ours, theirs);
+}
+
+static int matches_merge_filter(struct commit *commit)
+{
+	int is_merged;
+
+	if (merge_filter == NO_FILTER)
+		return 1;
+
+	is_merged = !!(commit->object.flags & UNINTERESTING);
+	return (is_merged == (merge_filter == SHOW_MERGED));
+}
+
+static void print_ref_item(struct ref_item *item, int maxwidth, int verbose,
+			   int abbrev, int current, char *prefix)
+{
+	char c;
+	int color;
+	struct commit *commit = item->commit;
+	struct strbuf out = STRBUF_INIT, name = STRBUF_INIT;
+
+	if (!matches_merge_filter(commit))
+		return;
+
+	switch (item->kind) {
+	case REF_LOCAL_BRANCH:
+		color = BRANCH_COLOR_LOCAL;
+		break;
+	case REF_REMOTE_BRANCH:
+		color = BRANCH_COLOR_REMOTE;
+		break;
+	default:
+		color = BRANCH_COLOR_PLAIN;
+		break;
+	}
+
+	c = ' ';
+	if (current) {
+		c = '*';
+		color = BRANCH_COLOR_CURRENT;
+	}
+
+	strbuf_addf(&name, "%s%s", prefix, item->name);
+	if (verbose)
+		strbuf_addf(&out, "%c %s%-*s%s", c, branch_get_color(color),
+			    maxwidth, name.buf,
+			    branch_get_color(BRANCH_COLOR_RESET));
+	else
+		strbuf_addf(&out, "%c %s%s%s", c, branch_get_color(color),
+			    name.buf, branch_get_color(BRANCH_COLOR_RESET));
+
+	if (item->dest)
+		strbuf_addf(&out, " -> %s", item->dest);
+	else if (verbose) {
+		struct strbuf subject = STRBUF_INIT, stat = STRBUF_INIT;
+		const char *sub = " **** invalid ref ****";
+
+		commit = item->commit;
+		if (commit && !parse_commit(commit)) {
+			struct pretty_print_context ctx = {0};
+			pretty_print_commit(CMIT_FMT_ONELINE, commit,
+					    &subject, &ctx);
+			sub = subject.buf;
+		}
+
+		if (item->kind == REF_LOCAL_BRANCH)
+			fill_tracking_info(&stat, item->name, verbose > 1);
+
+		strbuf_addf(&out, " %s %s%s",
+			find_unique_abbrev(item->commit->object.sha1, abbrev),
+			stat.buf, sub);
+		strbuf_release(&stat);
+		strbuf_release(&subject);
+	}
+	printf("%s\n", out.buf);
+	strbuf_release(&name);
+	strbuf_release(&out);
+}
+
+static int calc_maxwidth(struct ref_list *refs)
+{
+	int i, w = 0;
+	for (i = 0; i < refs->index; i++) {
+		if (!matches_merge_filter(refs->list[i].commit))
+			continue;
+		if (refs->list[i].len > w)
+			w = refs->list[i].len;
+	}
+	return w;
+}
+
+
+static void show_detached(struct ref_list *ref_list)
+{
+	struct commit *head_commit = lookup_commit_reference_gently(head_sha1, 1);
+
+	if (head_commit && is_descendant_of(head_commit, ref_list->with_commit)) {
+		struct ref_item item;
+		item.name = xstrdup("(no branch)");
+		item.len = strlen(item.name);
+		item.kind = REF_LOCAL_BRANCH;
+		item.dest = NULL;
+		item.commit = head_commit;
+		if (item.len > ref_list->maxwidth)
+			ref_list->maxwidth = item.len;
+		print_ref_item(&item, ref_list->maxwidth, ref_list->verbose, ref_list->abbrev, 1, "");
+		free(item.name);
+	}
+}
+
+static void print_ref_list(int kinds, int detached, int verbose, int abbrev, struct commit_list *with_commit)
+{
+	int i;
+	struct ref_list ref_list;
+
+	memset(&ref_list, 0, sizeof(ref_list));
+	ref_list.kinds = kinds;
+	ref_list.verbose = verbose;
+	ref_list.abbrev = abbrev;
+	ref_list.with_commit = with_commit;
+	if (merge_filter != NO_FILTER)
+		init_revisions(&ref_list.revs, NULL);
+	for_each_rawref(append_ref, &ref_list);
+	if (merge_filter != NO_FILTER) {
+		struct commit *filter;
+		filter = lookup_commit_reference_gently(merge_filter_ref, 0);
+		filter->object.flags |= UNINTERESTING;
+		add_pending_object(&ref_list.revs,
+				   (struct object *) filter, "");
+		ref_list.revs.limited = 1;
+		prepare_revision_walk(&ref_list.revs);
+		if (verbose)
+			ref_list.maxwidth = calc_maxwidth(&ref_list);
+	}
+
+	qsort(ref_list.list, ref_list.index, sizeof(struct ref_item), ref_cmp);
+
+	detached = (detached && (kinds & REF_LOCAL_BRANCH));
+	if (detached)
+		show_detached(&ref_list);
+
+	for (i = 0; i < ref_list.index; i++) {
+		int current = !detached &&
+			(ref_list.list[i].kind == REF_LOCAL_BRANCH) &&
+			!strcmp(ref_list.list[i].name, head);
+		char *prefix = (kinds != REF_REMOTE_BRANCH &&
+				ref_list.list[i].kind == REF_REMOTE_BRANCH)
+				? "remotes/" : "";
+		print_ref_item(&ref_list.list[i], ref_list.maxwidth, verbose,
+			       abbrev, current, prefix);
+	}
+
+	free_ref_list(&ref_list);
+}
+
+static void rename_branch(const char *oldname, const char *newname, int force)
+{
+	struct strbuf oldref = STRBUF_INIT, newref = STRBUF_INIT, logmsg = STRBUF_INIT;
+	unsigned char sha1[20];
+	struct strbuf oldsection = STRBUF_INIT, newsection = STRBUF_INIT;
+	int recovery = 0;
+
+	if (!oldname)
+		die("cannot rename the current branch while not on any.");
+
+	if (strbuf_check_branch_ref(&oldref, oldname)) {
+		/*
+		 * Bad name --- this could be an attempt to rename a
+		 * ref that we used to allow to be created by accident.
+		 */
+		if (resolve_ref(oldref.buf, sha1, 1, NULL))
+			recovery = 1;
+		else
+			die("Invalid branch name: '%s'", oldname);
+	}
+
+	if (strbuf_check_branch_ref(&newref, newname))
+		die("Invalid branch name: '%s'", newname);
+
+	if (resolve_ref(newref.buf, sha1, 1, NULL) && !force)
+		die("A branch named '%s' already exists.", newref.buf + 11);
+
+	strbuf_addf(&logmsg, "Branch: renamed %s to %s",
+		 oldref.buf, newref.buf);
+
+	if (rename_ref(oldref.buf, newref.buf, logmsg.buf))
+		die("Branch rename failed");
+	strbuf_release(&logmsg);
+
+	if (recovery)
+		warning("Renamed a misnamed branch '%s' away", oldref.buf + 11);
+
+	/* no need to pass logmsg here as HEAD didn't really move */
+	if (!strcmp(oldname, head) && create_symref("HEAD", newref.buf, NULL))
+		die("Branch renamed to %s, but HEAD is not updated!", newname);
+
+	strbuf_addf(&oldsection, "branch.%s", oldref.buf + 11);
+	strbuf_release(&oldref);
+	strbuf_addf(&newsection, "branch.%s", newref.buf + 11);
+	strbuf_release(&newref);
+	if (git_config_rename_section(oldsection.buf, newsection.buf) < 0)
+		die("Branch is renamed, but update of config-file failed");
+	strbuf_release(&oldsection);
+	strbuf_release(&newsection);
+}
+
+static int opt_parse_merge_filter(const struct option *opt, const char *arg, int unset)
+{
+	merge_filter = ((opt->long_name[0] == 'n')
+			? SHOW_NOT_MERGED
+			: SHOW_MERGED);
+	if (unset)
+		merge_filter = SHOW_NOT_MERGED; /* b/c for --no-merged */
+	if (!arg)
+		arg = "HEAD";
+	if (get_sha1(arg, merge_filter_ref))
+		die("malformed object name %s", arg);
+	return 0;
+}
+
+int cmd_branch(int argc, const char **argv, const char *prefix)
+{
+	int delete = 0, rename = 0, force_create = 0;
+	int verbose = 0, abbrev = DEFAULT_ABBREV, detached = 0;
+	int reflog = 0;
+	enum branch_track track;
+	int kinds = REF_LOCAL_BRANCH;
+	struct commit_list *with_commit = NULL;
+
+	struct option options[] = {
+		OPT_GROUP("Generic options"),
+		OPT__VERBOSE(&verbose),
+		OPT_SET_INT('t', "track",  &track, "set up tracking mode (see git-pull(1))",
+			BRANCH_TRACK_EXPLICIT),
+		OPT_SET_INT( 0, "set-upstream",  &track, "change upstream info",
+			BRANCH_TRACK_OVERRIDE),
+		OPT__COLOR(&branch_use_color, "use colored output"),
+		OPT_SET_INT('r', NULL,     &kinds, "act on remote-tracking branches",
+			REF_REMOTE_BRANCH),
+		{
+			OPTION_CALLBACK, 0, "contains", &with_commit, "commit",
+			"print only branches that contain the commit",
+			PARSE_OPT_LASTARG_DEFAULT,
+			parse_opt_with_commit, (intptr_t)"HEAD",
+		},
+		{
+			OPTION_CALLBACK, 0, "with", &with_commit, "commit",
+			"print only branches that contain the commit",
+			PARSE_OPT_HIDDEN | PARSE_OPT_LASTARG_DEFAULT,
+			parse_opt_with_commit, (intptr_t) "HEAD",
+		},
+		OPT__ABBREV(&abbrev),
+
+		OPT_GROUP("Specific git-branch actions:"),
+		OPT_SET_INT('a', NULL, &kinds, "list both remote-tracking and local branches",
+			REF_REMOTE_BRANCH | REF_LOCAL_BRANCH),
+		OPT_BIT('d', NULL, &delete, "delete fully merged branch", 1),
+		OPT_BIT('D', NULL, &delete, "delete branch (even if not merged)", 2),
+		OPT_BIT('m', NULL, &rename, "move/rename a branch and its reflog", 1),
+		OPT_BIT('M', NULL, &rename, "move/rename a branch, even if target exists", 2),
+		OPT_BOOLEAN('l', NULL, &reflog, "create the branch's reflog"),
+		OPT_BOOLEAN('f', "force", &force_create, "force creation (when already exists)"),
+		{
+			OPTION_CALLBACK, 0, "no-merged", &merge_filter_ref,
+			"commit", "print only not merged branches",
+			PARSE_OPT_LASTARG_DEFAULT | PARSE_OPT_NONEG,
+			opt_parse_merge_filter, (intptr_t) "HEAD",
+		},
+		{
+			OPTION_CALLBACK, 0, "merged", &merge_filter_ref,
+			"commit", "print only merged branches",
+			PARSE_OPT_LASTARG_DEFAULT | PARSE_OPT_NONEG,
+			opt_parse_merge_filter, (intptr_t) "HEAD",
+		},
+		OPT_END(),
+	};
+
+	git_config(git_branch_config, NULL);
+
+	if (branch_use_color == -1)
+		branch_use_color = git_use_color_default;
+
+	track = git_branch_track;
+
+	head = resolve_ref("HEAD", head_sha1, 0, NULL);
+	if (!head)
+		die("Failed to resolve HEAD as a valid ref.");
+	head = xstrdup(head);
+	if (!strcmp(head, "HEAD")) {
+		detached = 1;
+	} else {
+		if (prefixcmp(head, "refs/heads/"))
+			die("HEAD not found below refs/heads!");
+		head += 11;
+	}
+	hashcpy(merge_filter_ref, head_sha1);
+
+	argc = parse_options(argc, argv, prefix, options, builtin_branch_usage,
+			     0);
+	if (!!delete + !!rename + !!force_create > 1)
+		usage_with_options(builtin_branch_usage, options);
+
+	if (delete)
+		return delete_branches(argc, argv, delete > 1, kinds);
+	else if (argc == 0)
+		print_ref_list(kinds, detached, verbose, abbrev, with_commit);
+	else if (rename && (argc == 1))
+		rename_branch(head, argv[0], rename > 1);
+	else if (rename && (argc == 2))
+		rename_branch(argv[0], argv[1], rename > 1);
+	else if (argc <= 2) {
+		if (kinds != REF_LOCAL_BRANCH)
+			die("-a and -r options to 'git branch' do not make sense with a branch name");
+		create_branch(head, argv[0], (argc == 2) ? argv[1] : head,
+			      force_create, reflog, track);
+	} else
+		usage_with_options(builtin_branch_usage, options);
+
+	return 0;
+}
diff --git a/builtin/bundle.c b/builtin/bundle.c
new file mode 100644
index 0000000..2006cc5
--- /dev/null
+++ b/builtin/bundle.c
@@ -0,0 +1,67 @@
+#include "builtin.h"
+#include "cache.h"
+#include "bundle.h"
+
+/*
+ * Basic handler for bundle files to connect repositories via sneakernet.
+ * Invocation must include action.
+ * This function can create a bundle or provide information on an existing
+ * bundle supporting "fetch", "pull", and "ls-remote".
+ */
+
+static const char builtin_bundle_usage[] =
+  "git bundle create <file> <git-rev-list args>\n"
+  "   or: git bundle verify <file>\n"
+  "   or: git bundle list-heads <file> [refname...]\n"
+  "   or: git bundle unbundle <file> [refname...]";
+
+int cmd_bundle(int argc, const char **argv, const char *prefix)
+{
+	struct bundle_header header;
+	int nongit;
+	const char *cmd, *bundle_file;
+	int bundle_fd = -1;
+	char buffer[PATH_MAX];
+
+	if (argc < 3)
+		usage(builtin_bundle_usage);
+
+	cmd = argv[1];
+	bundle_file = argv[2];
+	argc -= 2;
+	argv += 2;
+
+	prefix = setup_git_directory_gently(&nongit);
+	if (prefix && bundle_file[0] != '/') {
+		snprintf(buffer, sizeof(buffer), "%s/%s", prefix, bundle_file);
+		bundle_file = buffer;
+	}
+
+	memset(&header, 0, sizeof(header));
+	if (strcmp(cmd, "create") && (bundle_fd =
+				read_bundle_header(bundle_file, &header)) < 0)
+		return 1;
+
+	if (!strcmp(cmd, "verify")) {
+		close(bundle_fd);
+		if (verify_bundle(&header, 1))
+			return 1;
+		fprintf(stderr, "%s is okay\n", bundle_file);
+		return 0;
+	}
+	if (!strcmp(cmd, "list-heads")) {
+		close(bundle_fd);
+		return !!list_bundle_refs(&header, argc, argv);
+	}
+	if (!strcmp(cmd, "create")) {
+		if (nongit)
+			die("Need a repository to create a bundle.");
+		return !!create_bundle(&header, bundle_file, argc, argv);
+	} else if (!strcmp(cmd, "unbundle")) {
+		if (nongit)
+			die("Need a repository to unbundle.");
+		return !!unbundle(&header, bundle_fd) ||
+			list_bundle_refs(&header, argc, argv);
+	} else
+		usage(builtin_bundle_usage);
+}
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
new file mode 100644
index 0000000..a933eaa
--- /dev/null
+++ b/builtin/cat-file.c
@@ -0,0 +1,258 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "exec_cmd.h"
+#include "tag.h"
+#include "tree.h"
+#include "builtin.h"
+#include "parse-options.h"
+
+#define BATCH 1
+#define BATCH_CHECK 2
+
+static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
+{
+	/* the parser in tag.c is useless here. */
+	const char *endp = buf + size;
+	const char *cp = buf;
+
+	while (cp < endp) {
+		char c = *cp++;
+		if (c != '\n')
+			continue;
+		if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
+			const char *tagger = cp;
+
+			/* Found the tagger line.  Copy out the contents
+			 * of the buffer so far.
+			 */
+			write_or_die(1, buf, cp - buf);
+
+			/*
+			 * Do something intelligent, like pretty-printing
+			 * the date.
+			 */
+			while (cp < endp) {
+				if (*cp++ == '\n') {
+					/* tagger to cp is a line
+					 * that has ident and time.
+					 */
+					const char *sp = tagger;
+					char *ep;
+					unsigned long date;
+					long tz;
+					while (sp < cp && *sp != '>')
+						sp++;
+					if (sp == cp) {
+						/* give up */
+						write_or_die(1, tagger,
+							     cp - tagger);
+						break;
+					}
+					while (sp < cp &&
+					       !('0' <= *sp && *sp <= '9'))
+						sp++;
+					write_or_die(1, tagger, sp - tagger);
+					date = strtoul(sp, &ep, 10);
+					tz = strtol(ep, NULL, 10);
+					sp = show_date(date, tz, 0);
+					write_or_die(1, sp, strlen(sp));
+					xwrite(1, "\n", 1);
+					break;
+				}
+			}
+			break;
+		}
+		if (cp < endp && *cp == '\n')
+			/* end of header */
+			break;
+	}
+	/* At this point, we have copied out the header up to the end of
+	 * the tagger line and cp points at one past \n.  It could be the
+	 * next header line after the tagger line, or it could be another
+	 * \n that marks the end of the headers.  We need to copy out the
+	 * remainder as is.
+	 */
+	if (cp < endp)
+		write_or_die(1, cp, endp - cp);
+}
+
+static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
+{
+	unsigned char sha1[20];
+	enum object_type type;
+	void *buf;
+	unsigned long size;
+
+	if (get_sha1(obj_name, sha1))
+		die("Not a valid object name %s", obj_name);
+
+	buf = NULL;
+	switch (opt) {
+	case 't':
+		type = sha1_object_info(sha1, NULL);
+		if (type > 0) {
+			printf("%s\n", typename(type));
+			return 0;
+		}
+		break;
+
+	case 's':
+		type = sha1_object_info(sha1, &size);
+		if (type > 0) {
+			printf("%lu\n", size);
+			return 0;
+		}
+		break;
+
+	case 'e':
+		return !has_sha1_file(sha1);
+
+	case 'p':
+		type = sha1_object_info(sha1, NULL);
+		if (type < 0)
+			die("Not a valid object name %s", obj_name);
+
+		/* custom pretty-print here */
+		if (type == OBJ_TREE) {
+			const char *ls_args[3] = {"ls-tree", obj_name, NULL};
+			return cmd_ls_tree(2, ls_args, NULL);
+		}
+
+		buf = read_sha1_file(sha1, &type, &size);
+		if (!buf)
+			die("Cannot read object %s", obj_name);
+		if (type == OBJ_TAG) {
+			pprint_tag(sha1, buf, size);
+			return 0;
+		}
+
+		/* otherwise just spit out the data */
+		break;
+	case 0:
+		buf = read_object_with_reference(sha1, exp_type, &size, NULL);
+		break;
+
+	default:
+		die("git cat-file: unknown option: %s", exp_type);
+	}
+
+	if (!buf)
+		die("git cat-file %s: bad file", obj_name);
+
+	write_or_die(1, buf, size);
+	return 0;
+}
+
+static int batch_one_object(const char *obj_name, int print_contents)
+{
+	unsigned char sha1[20];
+	enum object_type type = 0;
+	unsigned long size;
+	void *contents = contents;
+
+	if (!obj_name)
+	   return 1;
+
+	if (get_sha1(obj_name, sha1)) {
+		printf("%s missing\n", obj_name);
+		fflush(stdout);
+		return 0;
+	}
+
+	if (print_contents == BATCH)
+		contents = read_sha1_file(sha1, &type, &size);
+	else
+		type = sha1_object_info(sha1, &size);
+
+	if (type <= 0) {
+		printf("%s missing\n", obj_name);
+		fflush(stdout);
+		return 0;
+	}
+
+	printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
+	fflush(stdout);
+
+	if (print_contents == BATCH) {
+		write_or_die(1, contents, size);
+		printf("\n");
+		fflush(stdout);
+		free(contents);
+	}
+
+	return 0;
+}
+
+static int batch_objects(int print_contents)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
+		int error = batch_one_object(buf.buf, print_contents);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
+static const char * const cat_file_usage[] = {
+	"git cat-file (-t|-s|-e|-p|<type>) <object>",
+	"git cat-file (--batch|--batch-check) < <list_of_objects>",
+	NULL
+};
+
+int cmd_cat_file(int argc, const char **argv, const char *prefix)
+{
+	int opt = 0, batch = 0;
+	const char *exp_type = NULL, *obj_name = NULL;
+
+	const struct option options[] = {
+		OPT_GROUP("<type> can be one of: blob, tree, commit, tag"),
+		OPT_SET_INT('t', NULL, &opt, "show object type", 't'),
+		OPT_SET_INT('s', NULL, &opt, "show object size", 's'),
+		OPT_SET_INT('e', NULL, &opt,
+			    "exit with zero when there's no error", 'e'),
+		OPT_SET_INT('p', NULL, &opt, "pretty-print object's content", 'p'),
+		OPT_SET_INT(0, "batch", &batch,
+			    "show info and content of objects fed from the standard input",
+			    BATCH),
+		OPT_SET_INT(0, "batch-check", &batch,
+			    "show info about objects fed from the standard input",
+			    BATCH_CHECK),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+
+	if (argc != 3 && argc != 2)
+		usage_with_options(cat_file_usage, options);
+
+	argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
+
+	if (opt) {
+		if (argc == 1)
+			obj_name = argv[0];
+		else
+			usage_with_options(cat_file_usage, options);
+	}
+	if (!opt && !batch) {
+		if (argc == 2) {
+			exp_type = argv[0];
+			obj_name = argv[1];
+		} else
+			usage_with_options(cat_file_usage, options);
+	}
+	if (batch && (opt || argc)) {
+		usage_with_options(cat_file_usage, options);
+	}
+
+	if (batch)
+		return batch_objects(batch);
+
+	return cat_one_file(opt, exp_type, obj_name);
+}
diff --git a/builtin/check-attr.c b/builtin/check-attr.c
new file mode 100644
index 0000000..3016d29
--- /dev/null
+++ b/builtin/check-attr.c
@@ -0,0 +1,123 @@
+#include "builtin.h"
+#include "cache.h"
+#include "attr.h"
+#include "quote.h"
+#include "parse-options.h"
+
+static int stdin_paths;
+static const char * const check_attr_usage[] = {
+"git check-attr attr... [--] pathname...",
+"git check-attr --stdin attr... < <list-of-paths>",
+NULL
+};
+
+static int null_term_line;
+
+static const struct option check_attr_options[] = {
+	OPT_BOOLEAN(0 , "stdin", &stdin_paths, "read file names from stdin"),
+	OPT_BOOLEAN('z', NULL, &null_term_line,
+		"input paths are terminated by a null character"),
+	OPT_END()
+};
+
+static void check_attr(int cnt, struct git_attr_check *check,
+	const char** name, const char *file)
+{
+	int j;
+	if (git_checkattr(file, cnt, check))
+		die("git_checkattr died");
+	for (j = 0; j < cnt; j++) {
+		const char *value = check[j].value;
+
+		if (ATTR_TRUE(value))
+			value = "set";
+		else if (ATTR_FALSE(value))
+			value = "unset";
+		else if (ATTR_UNSET(value))
+			value = "unspecified";
+
+		quote_c_style(file, NULL, stdout, 0);
+		printf(": %s: %s\n", name[j], value);
+	}
+}
+
+static void check_attr_stdin_paths(int cnt, struct git_attr_check *check,
+	const char** name)
+{
+	struct strbuf buf, nbuf;
+	int line_termination = null_term_line ? 0 : '\n';
+
+	strbuf_init(&buf, 0);
+	strbuf_init(&nbuf, 0);
+	while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
+		if (line_termination && buf.buf[0] == '"') {
+			strbuf_reset(&nbuf);
+			if (unquote_c_style(&nbuf, buf.buf, NULL))
+				die("line is badly quoted");
+			strbuf_swap(&buf, &nbuf);
+		}
+		check_attr(cnt, check, name, buf.buf);
+		maybe_flush_or_die(stdout, "attribute to stdout");
+	}
+	strbuf_release(&buf);
+	strbuf_release(&nbuf);
+}
+
+int cmd_check_attr(int argc, const char **argv, const char *prefix)
+{
+	struct git_attr_check *check;
+	int cnt, i, doubledash;
+	const char *errstr = NULL;
+
+	argc = parse_options(argc, argv, prefix, check_attr_options,
+			     check_attr_usage, PARSE_OPT_KEEP_DASHDASH);
+	if (!argc)
+		usage_with_options(check_attr_usage, check_attr_options);
+
+	if (read_cache() < 0) {
+		die("invalid cache");
+	}
+
+	doubledash = -1;
+	for (i = 0; doubledash < 0 && i < argc; i++) {
+		if (!strcmp(argv[i], "--"))
+			doubledash = i;
+	}
+
+	/* If there is no double dash, we handle only one attribute */
+	if (doubledash < 0) {
+		cnt = 1;
+		doubledash = 0;
+	} else
+		cnt = doubledash;
+	doubledash++;
+
+	if (cnt <= 0)
+		errstr = "No attribute specified";
+	else if (stdin_paths && doubledash < argc)
+		errstr = "Can't specify files with --stdin";
+	if (errstr) {
+		error("%s", errstr);
+		usage_with_options(check_attr_usage, check_attr_options);
+	}
+
+	check = xcalloc(cnt, sizeof(*check));
+	for (i = 0; i < cnt; i++) {
+		const char *name;
+		struct git_attr *a;
+		name = argv[i];
+		a = git_attr(name);
+		if (!a)
+			return error("%s: not a valid attribute name", name);
+		check[i].attr = a;
+	}
+
+	if (stdin_paths)
+		check_attr_stdin_paths(cnt, check, argv);
+	else {
+		for (i = doubledash; i < argc; i++)
+			check_attr(cnt, check, argv, argv[i]);
+		maybe_flush_or_die(stdout, "attribute to stdout");
+	}
+	return 0;
+}
diff --git a/builtin/check-ref-format.c b/builtin/check-ref-format.c
new file mode 100644
index 0000000..b106c65
--- /dev/null
+++ b/builtin/check-ref-format.c
@@ -0,0 +1,61 @@
+/*
+ * GIT - The information manager from hell
+ */
+
+#include "cache.h"
+#include "refs.h"
+#include "builtin.h"
+#include "strbuf.h"
+
+static const char builtin_check_ref_format_usage[] =
+"git check-ref-format [--print] <refname>\n"
+"   or: git check-ref-format --branch <branchname-shorthand>";
+
+/*
+ * Replace each run of adjacent slashes in src with a single slash,
+ * and write the result to dst.
+ *
+ * This function is similar to normalize_path_copy(), but stripped down
+ * to meet check_ref_format's simpler needs.
+ */
+static void collapse_slashes(char *dst, const char *src)
+{
+	char ch;
+	char prev = '\0';
+
+	while ((ch = *src++) != '\0') {
+		if (prev == '/' && ch == prev)
+			continue;
+
+		*dst++ = ch;
+		prev = ch;
+	}
+	*dst = '\0';
+}
+
+int cmd_check_ref_format(int argc, const char **argv, const char *prefix)
+{
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage(builtin_check_ref_format_usage);
+
+	if (argc == 3 && !strcmp(argv[1], "--branch")) {
+		struct strbuf sb = STRBUF_INIT;
+
+		if (strbuf_check_branch_ref(&sb, argv[2]))
+			die("'%s' is not a valid branch name", argv[2]);
+		printf("%s\n", sb.buf + 11);
+		exit(0);
+	}
+	if (argc == 3 && !strcmp(argv[1], "--print")) {
+		char *refname = xmalloc(strlen(argv[2]) + 1);
+
+		if (check_ref_format(argv[2]))
+			exit(1);
+		collapse_slashes(refname, argv[2]);
+		printf("%s\n", refname);
+		exit(0);
+	}
+	if (argc != 2)
+		usage(builtin_check_ref_format_usage);
+	return !!check_ref_format(argv[1]);
+}
diff --git a/builtin/checkout-index.c b/builtin/checkout-index.c
new file mode 100644
index 0000000..a7a5ee1
--- /dev/null
+++ b/builtin/checkout-index.c
@@ -0,0 +1,315 @@
+/*
+ * Check-out files from the "current cache directory"
+ *
+ * Copyright (C) 2005 Linus Torvalds
+ *
+ * Careful: order of argument flags does matter. For example,
+ *
+ *	git checkout-index -a -f file.c
+ *
+ * Will first check out all files listed in the cache (but not
+ * overwrite any old ones), and then force-checkout "file.c" a
+ * second time (ie that one _will_ overwrite any old contents
+ * with the same filename).
+ *
+ * Also, just doing "git checkout-index" does nothing. You probably
+ * meant "git checkout-index -a". And if you want to force it, you
+ * want "git checkout-index -f -a".
+ *
+ * Intuitiveness is not the goal here. Repeatability is. The
+ * reason for the "no arguments means no work" thing is that
+ * from scripts you are supposed to be able to do things like
+ *
+ *	find . -name '*.h' -print0 | xargs -0 git checkout-index -f --
+ *
+ * or:
+ *
+ *	find . -name '*.h' -print0 | git checkout-index -f -z --stdin
+ *
+ * which will force all existing *.h files to be replaced with
+ * their cached copies. If an empty command line implied "all",
+ * then this would force-refresh everything in the cache, which
+ * was not the point.
+ *
+ * Oh, and the "--" is just a good idea when you know the rest
+ * will be filenames. Just so that you wouldn't have a filename
+ * of "-a" causing problems (not possible in the above example,
+ * but get used to it in scripting!).
+ */
+#include "builtin.h"
+#include "cache.h"
+#include "quote.h"
+#include "cache-tree.h"
+#include "parse-options.h"
+
+#define CHECKOUT_ALL 4
+static int line_termination = '\n';
+static int checkout_stage; /* default to checkout stage0 */
+static int to_tempfile;
+static char topath[4][PATH_MAX + 1];
+
+static struct checkout state;
+
+static void write_tempfile_record(const char *name, int prefix_length)
+{
+	int i;
+
+	if (CHECKOUT_ALL == checkout_stage) {
+		for (i = 1; i < 4; i++) {
+			if (i > 1)
+				putchar(' ');
+			if (topath[i][0])
+				fputs(topath[i], stdout);
+			else
+				putchar('.');
+		}
+	} else
+		fputs(topath[checkout_stage], stdout);
+
+	putchar('\t');
+	write_name_quoted(name + prefix_length, stdout, line_termination);
+
+	for (i = 0; i < 4; i++) {
+		topath[i][0] = 0;
+	}
+}
+
+static int checkout_file(const char *name, int prefix_length)
+{
+	int namelen = strlen(name);
+	int pos = cache_name_pos(name, namelen);
+	int has_same_name = 0;
+	int did_checkout = 0;
+	int errs = 0;
+
+	if (pos < 0)
+		pos = -pos - 1;
+
+	while (pos < active_nr) {
+		struct cache_entry *ce = active_cache[pos];
+		if (ce_namelen(ce) != namelen ||
+		    memcmp(ce->name, name, namelen))
+			break;
+		has_same_name = 1;
+		pos++;
+		if (ce_stage(ce) != checkout_stage
+		    && (CHECKOUT_ALL != checkout_stage || !ce_stage(ce)))
+			continue;
+		did_checkout = 1;
+		if (checkout_entry(ce, &state,
+		    to_tempfile ? topath[ce_stage(ce)] : NULL) < 0)
+			errs++;
+	}
+
+	if (did_checkout) {
+		if (to_tempfile)
+			write_tempfile_record(name, prefix_length);
+		return errs > 0 ? -1 : 0;
+	}
+
+	if (!state.quiet) {
+		fprintf(stderr, "git checkout-index: %s ", name);
+		if (!has_same_name)
+			fprintf(stderr, "is not in the cache");
+		else if (checkout_stage)
+			fprintf(stderr, "does not exist at stage %d",
+				checkout_stage);
+		else
+			fprintf(stderr, "is unmerged");
+		fputc('\n', stderr);
+	}
+	return -1;
+}
+
+static void checkout_all(const char *prefix, int prefix_length)
+{
+	int i, errs = 0;
+	struct cache_entry *last_ce = NULL;
+
+	for (i = 0; i < active_nr ; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (ce_stage(ce) != checkout_stage
+		    && (CHECKOUT_ALL != checkout_stage || !ce_stage(ce)))
+			continue;
+		if (prefix && *prefix &&
+		    (ce_namelen(ce) <= prefix_length ||
+		     memcmp(prefix, ce->name, prefix_length)))
+			continue;
+		if (last_ce && to_tempfile) {
+			if (ce_namelen(last_ce) != ce_namelen(ce)
+			    || memcmp(last_ce->name, ce->name, ce_namelen(ce)))
+				write_tempfile_record(last_ce->name, prefix_length);
+		}
+		if (checkout_entry(ce, &state,
+		    to_tempfile ? topath[ce_stage(ce)] : NULL) < 0)
+			errs++;
+		last_ce = ce;
+	}
+	if (last_ce && to_tempfile)
+		write_tempfile_record(last_ce->name, prefix_length);
+	if (errs)
+		/* we have already done our error reporting.
+		 * exit with the same code as die().
+		 */
+		exit(128);
+}
+
+static const char * const builtin_checkout_index_usage[] = {
+	"git checkout-index [options] [--] <file>...",
+	NULL
+};
+
+static struct lock_file lock_file;
+
+static int option_parse_u(const struct option *opt,
+			      const char *arg, int unset)
+{
+	int *newfd = opt->value;
+
+	state.refresh_cache = 1;
+	if (*newfd < 0)
+		*newfd = hold_locked_index(&lock_file, 1);
+	return 0;
+}
+
+static int option_parse_z(const struct option *opt,
+			  const char *arg, int unset)
+{
+	if (unset)
+		line_termination = '\n';
+	else
+		line_termination = 0;
+	return 0;
+}
+
+static int option_parse_prefix(const struct option *opt,
+			       const char *arg, int unset)
+{
+	state.base_dir = arg;
+	state.base_dir_len = strlen(arg);
+	return 0;
+}
+
+static int option_parse_stage(const struct option *opt,
+			      const char *arg, int unset)
+{
+	if (!strcmp(arg, "all")) {
+		to_tempfile = 1;
+		checkout_stage = CHECKOUT_ALL;
+	} else {
+		int ch = arg[0];
+		if ('1' <= ch && ch <= '3')
+			checkout_stage = arg[0] - '0';
+		else
+			die("stage should be between 1 and 3 or all");
+	}
+	return 0;
+}
+
+int cmd_checkout_index(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	int newfd = -1;
+	int all = 0;
+	int read_from_stdin = 0;
+	int prefix_length;
+	int force = 0, quiet = 0, not_new = 0;
+	struct option builtin_checkout_index_options[] = {
+		OPT_BOOLEAN('a', "all", &all,
+			"checks out all files in the index"),
+		OPT_BOOLEAN('f', "force", &force,
+			"forces overwrite of existing files"),
+		OPT__QUIET(&quiet),
+		OPT_BOOLEAN('n', "no-create", &not_new,
+			"don't checkout new files"),
+		{ OPTION_CALLBACK, 'u', "index", &newfd, NULL,
+			"update stat information in the index file",
+			PARSE_OPT_NOARG, option_parse_u },
+		{ OPTION_CALLBACK, 'z', NULL, NULL, NULL,
+			"paths are separated with NUL character",
+			PARSE_OPT_NOARG, option_parse_z },
+		OPT_BOOLEAN(0, "stdin", &read_from_stdin,
+			"read list of paths from the standard input"),
+		OPT_BOOLEAN(0, "temp", &to_tempfile,
+			"write the content to temporary files"),
+		OPT_CALLBACK(0, "prefix", NULL, "string",
+			"when creating files, prepend <string>",
+			option_parse_prefix),
+		OPT_CALLBACK(0, "stage", NULL, NULL,
+			"copy out the files from named stage",
+			option_parse_stage),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+	state.base_dir = "";
+	prefix_length = prefix ? strlen(prefix) : 0;
+
+	if (read_cache() < 0) {
+		die("invalid cache");
+	}
+
+	argc = parse_options(argc, argv, prefix, builtin_checkout_index_options,
+			builtin_checkout_index_usage, 0);
+	state.force = force;
+	state.quiet = quiet;
+	state.not_new = not_new;
+
+	if (state.base_dir_len || to_tempfile) {
+		/* when --prefix is specified we do not
+		 * want to update cache.
+		 */
+		if (state.refresh_cache) {
+			rollback_lock_file(&lock_file);
+			newfd = -1;
+		}
+		state.refresh_cache = 0;
+	}
+
+	/* Check out named files first */
+	for (i = 0; i < argc; i++) {
+		const char *arg = argv[i];
+		const char *p;
+
+		if (all)
+			die("git checkout-index: don't mix '--all' and explicit filenames");
+		if (read_from_stdin)
+			die("git checkout-index: don't mix '--stdin' and explicit filenames");
+		p = prefix_path(prefix, prefix_length, arg);
+		checkout_file(p, prefix_length);
+		if (p < arg || p > arg + strlen(arg))
+			free((char *)p);
+	}
+
+	if (read_from_stdin) {
+		struct strbuf buf = STRBUF_INIT, nbuf = STRBUF_INIT;
+
+		if (all)
+			die("git checkout-index: don't mix '--all' and '--stdin'");
+
+		while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
+			const char *p;
+			if (line_termination && buf.buf[0] == '"') {
+				strbuf_reset(&nbuf);
+				if (unquote_c_style(&nbuf, buf.buf, NULL))
+					die("line is badly quoted");
+				strbuf_swap(&buf, &nbuf);
+			}
+			p = prefix_path(prefix, prefix_length, buf.buf);
+			checkout_file(p, prefix_length);
+			if (p < buf.buf || p > buf.buf + buf.len)
+				free((char *)p);
+		}
+		strbuf_release(&nbuf);
+		strbuf_release(&buf);
+	}
+
+	if (all)
+		checkout_all(prefix, prefix_length);
+
+	if (0 <= newfd &&
+	    (write_cache(newfd, active_cache, active_nr) ||
+	     commit_locked_index(&lock_file)))
+		die("Unable to write new index file");
+	return 0;
+}
diff --git a/builtin/checkout.c b/builtin/checkout.c
new file mode 100644
index 0000000..acefaaf
--- /dev/null
+++ b/builtin/checkout.c
@@ -0,0 +1,835 @@
+#include "cache.h"
+#include "builtin.h"
+#include "parse-options.h"
+#include "refs.h"
+#include "commit.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "cache-tree.h"
+#include "unpack-trees.h"
+#include "dir.h"
+#include "run-command.h"
+#include "merge-recursive.h"
+#include "branch.h"
+#include "diff.h"
+#include "revision.h"
+#include "remote.h"
+#include "blob.h"
+#include "xdiff-interface.h"
+#include "ll-merge.h"
+#include "resolve-undo.h"
+
+static const char * const checkout_usage[] = {
+	"git checkout [options] <branch>",
+	"git checkout [options] [<branch>] -- <file>...",
+	NULL,
+};
+
+struct checkout_opts {
+	int quiet;
+	int merge;
+	int force;
+	int writeout_stage;
+	int writeout_error;
+
+	const char *new_branch;
+	int new_branch_log;
+	enum branch_track track;
+};
+
+static int post_checkout_hook(struct commit *old, struct commit *new,
+			      int changed)
+{
+	return run_hook(NULL, "post-checkout",
+			sha1_to_hex(old ? old->object.sha1 : null_sha1),
+			sha1_to_hex(new ? new->object.sha1 : null_sha1),
+			changed ? "1" : "0", NULL);
+	/* "new" can be NULL when checking out from the index before
+	   a commit exists. */
+
+}
+
+static int update_some(const unsigned char *sha1, const char *base, int baselen,
+		const char *pathname, unsigned mode, int stage, void *context)
+{
+	int len;
+	struct cache_entry *ce;
+
+	if (S_ISDIR(mode))
+		return READ_TREE_RECURSIVE;
+
+	len = baselen + strlen(pathname);
+	ce = xcalloc(1, cache_entry_size(len));
+	hashcpy(ce->sha1, sha1);
+	memcpy(ce->name, base, baselen);
+	memcpy(ce->name + baselen, pathname, len - baselen);
+	ce->ce_flags = create_ce_flags(len, 0);
+	ce->ce_mode = create_ce_mode(mode);
+	add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
+	return 0;
+}
+
+static int read_tree_some(struct tree *tree, const char **pathspec)
+{
+	read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
+
+	/* update the index with the given tree's info
+	 * for all args, expanding wildcards, and exit
+	 * with any non-zero return code.
+	 */
+	return 0;
+}
+
+static int skip_same_name(struct cache_entry *ce, int pos)
+{
+	while (++pos < active_nr &&
+	       !strcmp(active_cache[pos]->name, ce->name))
+		; /* skip */
+	return pos;
+}
+
+static int check_stage(int stage, struct cache_entry *ce, int pos)
+{
+	while (pos < active_nr &&
+	       !strcmp(active_cache[pos]->name, ce->name)) {
+		if (ce_stage(active_cache[pos]) == stage)
+			return 0;
+		pos++;
+	}
+	return error("path '%s' does not have %s version",
+		     ce->name,
+		     (stage == 2) ? "our" : "their");
+}
+
+static int check_all_stages(struct cache_entry *ce, int pos)
+{
+	if (ce_stage(ce) != 1 ||
+	    active_nr <= pos + 2 ||
+	    strcmp(active_cache[pos+1]->name, ce->name) ||
+	    ce_stage(active_cache[pos+1]) != 2 ||
+	    strcmp(active_cache[pos+2]->name, ce->name) ||
+	    ce_stage(active_cache[pos+2]) != 3)
+		return error("path '%s' does not have all three versions",
+			     ce->name);
+	return 0;
+}
+
+static int checkout_stage(int stage, struct cache_entry *ce, int pos,
+			  struct checkout *state)
+{
+	while (pos < active_nr &&
+	       !strcmp(active_cache[pos]->name, ce->name)) {
+		if (ce_stage(active_cache[pos]) == stage)
+			return checkout_entry(active_cache[pos], state, NULL);
+		pos++;
+	}
+	return error("path '%s' does not have %s version",
+		     ce->name,
+		     (stage == 2) ? "our" : "their");
+}
+
+static int checkout_merged(int pos, struct checkout *state)
+{
+	struct cache_entry *ce = active_cache[pos];
+	const char *path = ce->name;
+	mmfile_t ancestor, ours, theirs;
+	int status;
+	unsigned char sha1[20];
+	mmbuffer_t result_buf;
+
+	if (ce_stage(ce) != 1 ||
+	    active_nr <= pos + 2 ||
+	    strcmp(active_cache[pos+1]->name, path) ||
+	    ce_stage(active_cache[pos+1]) != 2 ||
+	    strcmp(active_cache[pos+2]->name, path) ||
+	    ce_stage(active_cache[pos+2]) != 3)
+		return error("path '%s' does not have all 3 versions", path);
+
+	read_mmblob(&ancestor, active_cache[pos]->sha1);
+	read_mmblob(&ours, active_cache[pos+1]->sha1);
+	read_mmblob(&theirs, active_cache[pos+2]->sha1);
+
+	status = ll_merge(&result_buf, path, &ancestor,
+			  &ours, "ours", &theirs, "theirs", 0);
+	free(ancestor.ptr);
+	free(ours.ptr);
+	free(theirs.ptr);
+	if (status < 0 || !result_buf.ptr) {
+		free(result_buf.ptr);
+		return error("path '%s': cannot merge", path);
+	}
+
+	/*
+	 * NEEDSWORK:
+	 * There is absolutely no reason to write this as a blob object
+	 * and create a phony cache entry just to leak.  This hack is
+	 * primarily to get to the write_entry() machinery that massages
+	 * the contents to work-tree format and writes out which only
+	 * allows it for a cache entry.  The code in write_entry() needs
+	 * to be refactored to allow us to feed a <buffer, size, mode>
+	 * instead of a cache entry.  Such a refactoring would help
+	 * merge_recursive as well (it also writes the merge result to the
+	 * object database even when it may contain conflicts).
+	 */
+	if (write_sha1_file(result_buf.ptr, result_buf.size,
+			    blob_type, sha1))
+		die("Unable to add merge result for '%s'", path);
+	ce = make_cache_entry(create_ce_mode(active_cache[pos+1]->ce_mode),
+			      sha1,
+			      path, 2, 0);
+	if (!ce)
+		die("make_cache_entry failed for path '%s'", path);
+	status = checkout_entry(ce, state, NULL);
+	return status;
+}
+
+static int checkout_paths(struct tree *source_tree, const char **pathspec,
+			  struct checkout_opts *opts)
+{
+	int pos;
+	struct checkout state;
+	static char *ps_matched;
+	unsigned char rev[20];
+	int flag;
+	struct commit *head;
+	int errs = 0;
+	int stage = opts->writeout_stage;
+	int merge = opts->merge;
+	int newfd;
+	struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
+
+	newfd = hold_locked_index(lock_file, 1);
+	if (read_cache_preload(pathspec) < 0)
+		return error("corrupt index file");
+
+	if (source_tree)
+		read_tree_some(source_tree, pathspec);
+
+	for (pos = 0; pathspec[pos]; pos++)
+		;
+	ps_matched = xcalloc(1, pos);
+
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+		match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, ps_matched);
+	}
+
+	if (report_path_error(ps_matched, pathspec, 0))
+		return 1;
+
+	/* "checkout -m path" to recreate conflicted state */
+	if (opts->merge)
+		unmerge_cache(pathspec);
+
+	/* Any unmerged paths? */
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+		if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
+			if (!ce_stage(ce))
+				continue;
+			if (opts->force) {
+				warning("path '%s' is unmerged", ce->name);
+			} else if (stage) {
+				errs |= check_stage(stage, ce, pos);
+			} else if (opts->merge) {
+				errs |= check_all_stages(ce, pos);
+			} else {
+				errs = 1;
+				error("path '%s' is unmerged", ce->name);
+			}
+			pos = skip_same_name(ce, pos) - 1;
+		}
+	}
+	if (errs)
+		return 1;
+
+	/* Now we are committed to check them out */
+	memset(&state, 0, sizeof(state));
+	state.force = 1;
+	state.refresh_cache = 1;
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+		if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
+			if (!ce_stage(ce)) {
+				errs |= checkout_entry(ce, &state, NULL);
+				continue;
+			}
+			if (stage)
+				errs |= checkout_stage(stage, ce, pos, &state);
+			else if (merge)
+				errs |= checkout_merged(pos, &state);
+			pos = skip_same_name(ce, pos) - 1;
+		}
+	}
+
+	if (write_cache(newfd, active_cache, active_nr) ||
+	    commit_locked_index(lock_file))
+		die("unable to write new index file");
+
+	resolve_ref("HEAD", rev, 0, &flag);
+	head = lookup_commit_reference_gently(rev, 1);
+
+	errs |= post_checkout_hook(head, head, 0);
+	return errs;
+}
+
+static void show_local_changes(struct object *head)
+{
+	struct rev_info rev;
+	/* I think we want full paths, even if we're in a subdirectory. */
+	init_revisions(&rev, NULL);
+	rev.abbrev = 0;
+	rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
+	if (diff_setup_done(&rev.diffopt) < 0)
+		die("diff_setup_done failed");
+	add_pending_object(&rev, head, NULL);
+	run_diff_index(&rev, 0);
+}
+
+static void describe_detached_head(char *msg, struct commit *commit)
+{
+	struct strbuf sb = STRBUF_INIT;
+	struct pretty_print_context ctx = {0};
+	parse_commit(commit);
+	pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, &ctx);
+	fprintf(stderr, "%s %s... %s\n", msg,
+		find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
+	strbuf_release(&sb);
+}
+
+static int reset_tree(struct tree *tree, struct checkout_opts *o, int worktree)
+{
+	struct unpack_trees_options opts;
+	struct tree_desc tree_desc;
+
+	memset(&opts, 0, sizeof(opts));
+	opts.head_idx = -1;
+	opts.update = worktree;
+	opts.skip_unmerged = !worktree;
+	opts.reset = 1;
+	opts.merge = 1;
+	opts.fn = oneway_merge;
+	opts.verbose_update = !o->quiet;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
+	parse_tree(tree);
+	init_tree_desc(&tree_desc, tree->buffer, tree->size);
+	switch (unpack_trees(1, &tree_desc, &opts)) {
+	case -2:
+		o->writeout_error = 1;
+		/*
+		 * We return 0 nevertheless, as the index is all right
+		 * and more importantly we have made best efforts to
+		 * update paths in the work tree, and we cannot revert
+		 * them.
+		 */
+	case 0:
+		return 0;
+	default:
+		return 128;
+	}
+}
+
+struct branch_info {
+	const char *name; /* The short name used */
+	const char *path; /* The full name of a real branch */
+	struct commit *commit; /* The named commit */
+};
+
+static void setup_branch_path(struct branch_info *branch)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	strbuf_branchname(&buf, branch->name);
+	if (strcmp(buf.buf, branch->name))
+		branch->name = xstrdup(buf.buf);
+	strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
+	branch->path = strbuf_detach(&buf, NULL);
+}
+
+static int merge_working_tree(struct checkout_opts *opts,
+			      struct branch_info *old, struct branch_info *new)
+{
+	int ret;
+	struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
+	int newfd = hold_locked_index(lock_file, 1);
+
+	if (read_cache_preload(NULL) < 0)
+		return error("corrupt index file");
+
+	resolve_undo_clear();
+	if (opts->force) {
+		ret = reset_tree(new->commit->tree, opts, 1);
+		if (ret)
+			return ret;
+	} else {
+		struct tree_desc trees[2];
+		struct tree *tree;
+		struct unpack_trees_options topts;
+
+		memset(&topts, 0, sizeof(topts));
+		topts.head_idx = -1;
+		topts.src_index = &the_index;
+		topts.dst_index = &the_index;
+
+		topts.msgs.not_uptodate_file = "You have local changes to '%s'; cannot switch branches.";
+
+		refresh_cache(REFRESH_QUIET);
+
+		if (unmerged_cache()) {
+			error("you need to resolve your current index first");
+			return 1;
+		}
+
+		/* 2-way merge to the new branch */
+		topts.initial_checkout = is_cache_unborn();
+		topts.update = 1;
+		topts.merge = 1;
+		topts.gently = opts->merge && old->commit;
+		topts.verbose_update = !opts->quiet;
+		topts.fn = twoway_merge;
+		topts.dir = xcalloc(1, sizeof(*topts.dir));
+		topts.dir->flags |= DIR_SHOW_IGNORED;
+		topts.dir->exclude_per_dir = ".gitignore";
+		tree = parse_tree_indirect(old->commit ?
+					   old->commit->object.sha1 :
+					   (unsigned char *)EMPTY_TREE_SHA1_BIN);
+		init_tree_desc(&trees[0], tree->buffer, tree->size);
+		tree = parse_tree_indirect(new->commit->object.sha1);
+		init_tree_desc(&trees[1], tree->buffer, tree->size);
+
+		ret = unpack_trees(2, trees, &topts);
+		if (ret == -1) {
+			/*
+			 * Unpack couldn't do a trivial merge; either
+			 * give up or do a real merge, depending on
+			 * whether the merge flag was used.
+			 */
+			struct tree *result;
+			struct tree *work;
+			struct merge_options o;
+			if (!opts->merge)
+				return 1;
+
+			/*
+			 * Without old->commit, the below is the same as
+			 * the two-tree unpack we already tried and failed.
+			 */
+			if (!old->commit)
+				return 1;
+
+			/* Do more real merge */
+
+			/*
+			 * We update the index fully, then write the
+			 * tree from the index, then merge the new
+			 * branch with the current tree, with the old
+			 * branch as the base. Then we reset the index
+			 * (but not the working tree) to the new
+			 * branch, leaving the working tree as the
+			 * merged version, but skipping unmerged
+			 * entries in the index.
+			 */
+
+			add_files_to_cache(NULL, NULL, 0);
+			init_merge_options(&o);
+			o.verbosity = 0;
+			work = write_tree_from_memory(&o);
+
+			ret = reset_tree(new->commit->tree, opts, 1);
+			if (ret)
+				return ret;
+			o.branch1 = new->name;
+			o.branch2 = "local";
+			merge_trees(&o, new->commit->tree, work,
+				old->commit->tree, &result);
+			ret = reset_tree(new->commit->tree, opts, 0);
+			if (ret)
+				return ret;
+		}
+	}
+
+	if (write_cache(newfd, active_cache, active_nr) ||
+	    commit_locked_index(lock_file))
+		die("unable to write new index file");
+
+	if (!opts->force && !opts->quiet)
+		show_local_changes(&new->commit->object);
+
+	return 0;
+}
+
+static void report_tracking(struct branch_info *new)
+{
+	struct strbuf sb = STRBUF_INIT;
+	struct branch *branch = branch_get(new->name);
+
+	if (!format_tracking_info(branch, &sb))
+		return;
+	fputs(sb.buf, stdout);
+	strbuf_release(&sb);
+}
+
+static void detach_advice(const char *old_path, const char *new_name)
+{
+	const char fmt[] =
+	"Note: checking out '%s'.\n\n"
+	"You are in 'detached HEAD' state. You can look around, make experimental\n"
+	"changes and commit them, and you can discard any commits you make in this\n"
+	"state without impacting any branches by performing another checkout.\n\n"
+	"If you want to create a new branch to retain commits you create, you may\n"
+	"do so (now or later) by using -b with the checkout command again. Example:\n\n"
+	"  git checkout -b new_branch_name\n\n";
+
+	fprintf(stderr, fmt, new_name);
+}
+
+static void update_refs_for_switch(struct checkout_opts *opts,
+				   struct branch_info *old,
+				   struct branch_info *new)
+{
+	struct strbuf msg = STRBUF_INIT;
+	const char *old_desc;
+	if (opts->new_branch) {
+		create_branch(old->name, opts->new_branch, new->name, 0,
+			      opts->new_branch_log, opts->track);
+		new->name = opts->new_branch;
+		setup_branch_path(new);
+	}
+
+	old_desc = old->name;
+	if (!old_desc && old->commit)
+		old_desc = sha1_to_hex(old->commit->object.sha1);
+	strbuf_addf(&msg, "checkout: moving from %s to %s",
+		    old_desc ? old_desc : "(invalid)", new->name);
+
+	if (new->path) {
+		create_symref("HEAD", new->path, msg.buf);
+		if (!opts->quiet) {
+			if (old->path && !strcmp(new->path, old->path))
+				fprintf(stderr, "Already on '%s'\n",
+					new->name);
+			else
+				fprintf(stderr, "Switched to%s branch '%s'\n",
+					opts->new_branch ? " a new" : "",
+					new->name);
+		}
+	} else if (strcmp(new->name, "HEAD")) {
+		update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
+			   REF_NODEREF, DIE_ON_ERR);
+		if (!opts->quiet) {
+			if (old->path && advice_detached_head)
+				detach_advice(old->path, new->name);
+			describe_detached_head("HEAD is now at", new->commit);
+		}
+	}
+	remove_branch_state();
+	strbuf_release(&msg);
+	if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD")))
+		report_tracking(new);
+}
+
+static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
+{
+	int ret = 0;
+	struct branch_info old;
+	unsigned char rev[20];
+	int flag;
+	memset(&old, 0, sizeof(old));
+	old.path = resolve_ref("HEAD", rev, 0, &flag);
+	old.commit = lookup_commit_reference_gently(rev, 1);
+	if (!(flag & REF_ISSYMREF))
+		old.path = NULL;
+
+	if (old.path && !prefixcmp(old.path, "refs/heads/"))
+		old.name = old.path + strlen("refs/heads/");
+
+	if (!new->name) {
+		new->name = "HEAD";
+		new->commit = old.commit;
+		if (!new->commit)
+			die("You are on a branch yet to be born");
+		parse_commit(new->commit);
+	}
+
+	ret = merge_working_tree(opts, &old, new);
+	if (ret)
+		return ret;
+
+	/*
+	 * If we were on a detached HEAD, but have now moved to
+	 * a new commit, we want to mention the old commit once more
+	 * to remind the user that it might be lost.
+	 */
+	if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
+		describe_detached_head("Previous HEAD position was", old.commit);
+
+	update_refs_for_switch(opts, &old, new);
+
+	ret = post_checkout_hook(old.commit, new->commit, 1);
+	return ret || opts->writeout_error;
+}
+
+static int git_checkout_config(const char *var, const char *value, void *cb)
+{
+	return git_xmerge_config(var, value, cb);
+}
+
+static int interactive_checkout(const char *revision, const char **pathspec,
+				struct checkout_opts *opts)
+{
+	return run_add_interactive(revision, "--patch=checkout", pathspec);
+}
+
+struct tracking_name_data {
+	const char *name;
+	char *remote;
+	int unique;
+};
+
+static int check_tracking_name(const char *refname, const unsigned char *sha1,
+			       int flags, void *cb_data)
+{
+	struct tracking_name_data *cb = cb_data;
+	const char *slash;
+
+	if (prefixcmp(refname, "refs/remotes/"))
+		return 0;
+	slash = strchr(refname + 13, '/');
+	if (!slash || strcmp(slash + 1, cb->name))
+		return 0;
+	if (cb->remote) {
+		cb->unique = 0;
+		return 0;
+	}
+	cb->remote = xstrdup(refname);
+	return 0;
+}
+
+static const char *unique_tracking_name(const char *name)
+{
+	struct tracking_name_data cb_data = { name, NULL, 1 };
+	for_each_ref(check_tracking_name, &cb_data);
+	if (cb_data.unique)
+		return cb_data.remote;
+	free(cb_data.remote);
+	return NULL;
+}
+
+int cmd_checkout(int argc, const char **argv, const char *prefix)
+{
+	struct checkout_opts opts;
+	unsigned char rev[20];
+	const char *arg;
+	struct branch_info new;
+	struct tree *source_tree = NULL;
+	char *conflict_style = NULL;
+	int patch_mode = 0;
+	int dwim_new_local_branch = 1;
+	struct option options[] = {
+		OPT__QUIET(&opts.quiet),
+		OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
+		OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"),
+		OPT_SET_INT('t', "track",  &opts.track, "track",
+			BRANCH_TRACK_EXPLICIT),
+		OPT_SET_INT('2', "ours", &opts.writeout_stage, "stage",
+			    2),
+		OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage",
+			    3),
+		OPT_BOOLEAN('f', "force", &opts.force, "force"),
+		OPT_BOOLEAN('m', "merge", &opts.merge, "merge"),
+		OPT_STRING(0, "conflict", &conflict_style, "style",
+			   "conflict style (merge or diff3)"),
+		OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
+		{ OPTION_BOOLEAN, 0, "guess", &dwim_new_local_branch, NULL,
+		  "second guess 'git checkout no-such-branch'",
+		  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
+		OPT_END(),
+	};
+	int has_dash_dash;
+
+	memset(&opts, 0, sizeof(opts));
+	memset(&new, 0, sizeof(new));
+
+	git_config(git_checkout_config, NULL);
+
+	opts.track = BRANCH_TRACK_UNSPECIFIED;
+
+	argc = parse_options(argc, argv, prefix, options, checkout_usage,
+			     PARSE_OPT_KEEP_DASHDASH);
+
+	if (patch_mode && (opts.track > 0 || opts.new_branch
+			   || opts.new_branch_log || opts.merge || opts.force))
+		die ("--patch is incompatible with all other options");
+
+	/* --track without -b should DWIM */
+	if (0 < opts.track && !opts.new_branch) {
+		const char *argv0 = argv[0];
+		if (!argc || !strcmp(argv0, "--"))
+			die ("--track needs a branch name");
+		if (!prefixcmp(argv0, "refs/"))
+			argv0 += 5;
+		if (!prefixcmp(argv0, "remotes/"))
+			argv0 += 8;
+		argv0 = strchr(argv0, '/');
+		if (!argv0 || !argv0[1])
+			die ("Missing branch name; try -b");
+		opts.new_branch = argv0 + 1;
+	}
+
+	if (conflict_style) {
+		opts.merge = 1; /* implied */
+		git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
+	}
+
+	if (opts.force && opts.merge)
+		die("git checkout: -f and -m are incompatible");
+
+	/*
+	 * case 1: git checkout <ref> -- [<paths>]
+	 *
+	 *   <ref> must be a valid tree, everything after the '--' must be
+	 *   a path.
+	 *
+	 * case 2: git checkout -- [<paths>]
+	 *
+	 *   everything after the '--' must be paths.
+	 *
+	 * case 3: git checkout <something> [<paths>]
+	 *
+	 *   With no paths, if <something> is a commit, that is to
+	 *   switch to the branch or detach HEAD at it.  As a special case,
+	 *   if <something> is A...B (missing A or B means HEAD but you can
+	 *   omit at most one side), and if there is a unique merge base
+	 *   between A and B, A...B names that merge base.
+	 *
+	 *   With no paths, if <something> is _not_ a commit, no -t nor -b
+	 *   was given, and there is a tracking branch whose name is
+	 *   <something> in one and only one remote, then this is a short-hand
+	 *   to fork local <something> from that remote tracking branch.
+	 *
+	 *   Otherwise <something> shall not be ambiguous.
+	 *   - If it's *only* a reference, treat it like case (1).
+	 *   - If it's only a path, treat it like case (2).
+	 *   - else: fail.
+	 *
+	 */
+	if (argc) {
+		if (!strcmp(argv[0], "--")) {       /* case (2) */
+			argv++;
+			argc--;
+			goto no_reference;
+		}
+
+		arg = argv[0];
+		has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
+
+		if (!strcmp(arg, "-"))
+			arg = "@{-1}";
+
+		if (get_sha1_mb(arg, rev)) {
+			if (has_dash_dash)          /* case (1) */
+				die("invalid reference: %s", arg);
+			if (!patch_mode &&
+			    dwim_new_local_branch &&
+			    opts.track == BRANCH_TRACK_UNSPECIFIED &&
+			    !opts.new_branch &&
+			    !check_filename(NULL, arg) &&
+			    argc == 1) {
+				const char *remote = unique_tracking_name(arg);
+				if (!remote || get_sha1(remote, rev))
+					goto no_reference;
+				opts.new_branch = arg;
+				arg = remote;
+				/* DWIMmed to create local branch */
+			}
+			else
+				goto no_reference;
+		}
+
+		/* we can't end up being in (2) anymore, eat the argument */
+		argv++;
+		argc--;
+
+		new.name = arg;
+		if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
+			setup_branch_path(&new);
+
+			if ((check_ref_format(new.path) == CHECK_REF_FORMAT_OK) &&
+			    resolve_ref(new.path, rev, 1, NULL))
+				;
+			else
+				new.path = NULL;
+			parse_commit(new.commit);
+			source_tree = new.commit->tree;
+		} else
+			source_tree = parse_tree_indirect(rev);
+
+		if (!source_tree)                   /* case (1): want a tree */
+			die("reference is not a tree: %s", arg);
+		if (!has_dash_dash) {/* case (3 -> 1) */
+			/*
+			 * Do not complain the most common case
+			 *	git checkout branch
+			 * even if there happen to be a file called 'branch';
+			 * it would be extremely annoying.
+			 */
+			if (argc)
+				verify_non_filename(NULL, arg);
+		}
+		else {
+			argv++;
+			argc--;
+		}
+	}
+
+no_reference:
+
+	if (opts.track == BRANCH_TRACK_UNSPECIFIED)
+		opts.track = git_branch_track;
+
+	if (argc) {
+		const char **pathspec = get_pathspec(prefix, argv);
+
+		if (!pathspec)
+			die("invalid path specification");
+
+		if (patch_mode)
+			return interactive_checkout(new.name, pathspec, &opts);
+
+		/* Checkout paths */
+		if (opts.new_branch) {
+			if (argc == 1) {
+				die("git checkout: updating paths is incompatible with switching branches.\nDid you intend to checkout '%s' which can not be resolved as commit?", argv[0]);
+			} else {
+				die("git checkout: updating paths is incompatible with switching branches.");
+			}
+		}
+
+		if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
+			die("git checkout: --ours/--theirs, --force and --merge are incompatible when\nchecking out of the index.");
+
+		return checkout_paths(source_tree, pathspec, &opts);
+	}
+
+	if (patch_mode)
+		return interactive_checkout(new.name, NULL, &opts);
+
+	if (opts.new_branch) {
+		struct strbuf buf = STRBUF_INIT;
+		if (strbuf_check_branch_ref(&buf, opts.new_branch))
+			die("git checkout: we do not like '%s' as a branch name.",
+			    opts.new_branch);
+		if (!get_sha1(buf.buf, rev))
+			die("git checkout: branch %s already exists", opts.new_branch);
+		strbuf_release(&buf);
+	}
+
+	if (new.name && !new.commit) {
+		die("Cannot switch branch to a non-commit.");
+	}
+	if (opts.writeout_stage)
+		die("--ours/--theirs is incompatible with switching branches.");
+
+	return switch_branches(&opts, &new);
+}
diff --git a/builtin/clean.c b/builtin/clean.c
new file mode 100644
index 0000000..fac64e6
--- /dev/null
+++ b/builtin/clean.c
@@ -0,0 +1,171 @@
+/*
+ * "git clean" builtin command
+ *
+ * Copyright (C) 2007 Shawn Bohrer
+ *
+ * Based on git-clean.sh by Pavel Roskin
+ */
+
+#include "builtin.h"
+#include "cache.h"
+#include "dir.h"
+#include "parse-options.h"
+#include "quote.h"
+
+static int force = -1; /* unset */
+
+static const char *const builtin_clean_usage[] = {
+	"git clean [-d] [-f] [-n] [-q] [-x | -X] [--] <paths>...",
+	NULL
+};
+
+static int git_clean_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "clean.requireforce"))
+		force = !git_config_bool(var, value);
+	return git_default_config(var, value, cb);
+}
+
+int cmd_clean(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	int show_only = 0, remove_directories = 0, quiet = 0, ignored = 0;
+	int ignored_only = 0, baselen = 0, config_set = 0, errors = 0;
+	int rm_flags = REMOVE_DIR_KEEP_NESTED_GIT;
+	struct strbuf directory = STRBUF_INIT;
+	struct dir_struct dir;
+	static const char **pathspec;
+	struct strbuf buf = STRBUF_INIT;
+	const char *qname;
+	char *seen = NULL;
+	struct option options[] = {
+		OPT__QUIET(&quiet),
+		OPT__DRY_RUN(&show_only),
+		OPT_BOOLEAN('f', "force", &force, "force"),
+		OPT_BOOLEAN('d', NULL, &remove_directories,
+				"remove whole directories"),
+		OPT_BOOLEAN('x', NULL, &ignored, "remove ignored files, too"),
+		OPT_BOOLEAN('X', NULL, &ignored_only,
+				"remove only ignored files"),
+		OPT_END()
+	};
+
+	git_config(git_clean_config, NULL);
+	if (force < 0)
+		force = 0;
+	else
+		config_set = 1;
+
+	argc = parse_options(argc, argv, prefix, options, builtin_clean_usage,
+			     0);
+
+	memset(&dir, 0, sizeof(dir));
+	if (ignored_only)
+		dir.flags |= DIR_SHOW_IGNORED;
+
+	if (ignored && ignored_only)
+		die("-x and -X cannot be used together");
+
+	if (!show_only && !force)
+		die("clean.requireForce %s to true and neither -n nor -f given; "
+		    "refusing to clean", config_set ? "set" : "defaults");
+
+	if (force > 1)
+		rm_flags = 0;
+
+	dir.flags |= DIR_SHOW_OTHER_DIRECTORIES;
+
+	if (read_cache() < 0)
+		die("index file corrupt");
+
+	if (!ignored)
+		setup_standard_excludes(&dir);
+
+	pathspec = get_pathspec(prefix, argv);
+
+	fill_directory(&dir, pathspec);
+
+	if (pathspec)
+		seen = xmalloc(argc > 0 ? argc : 1);
+
+	for (i = 0; i < dir.nr; i++) {
+		struct dir_entry *ent = dir.entries[i];
+		int len, pos;
+		int matches = 0;
+		struct cache_entry *ce;
+		struct stat st;
+
+		/*
+		 * Remove the '/' at the end that directory
+		 * walking adds for directory entries.
+		 */
+		len = ent->len;
+		if (len && ent->name[len-1] == '/')
+			len--;
+		pos = cache_name_pos(ent->name, len);
+		if (0 <= pos)
+			continue;	/* exact match */
+		pos = -pos - 1;
+		if (pos < active_nr) {
+			ce = active_cache[pos];
+			if (ce_namelen(ce) == len &&
+			    !memcmp(ce->name, ent->name, len))
+				continue; /* Yup, this one exists unmerged */
+		}
+
+		/*
+		 * we might have removed this as part of earlier
+		 * recursive directory removal, so lstat() here could
+		 * fail with ENOENT.
+		 */
+		if (lstat(ent->name, &st))
+			continue;
+
+		if (pathspec) {
+			memset(seen, 0, argc > 0 ? argc : 1);
+			matches = match_pathspec(pathspec, ent->name, len,
+						 baselen, seen);
+		}
+
+		if (S_ISDIR(st.st_mode)) {
+			strbuf_addstr(&directory, ent->name);
+			qname = quote_path_relative(directory.buf, directory.len, &buf, prefix);
+			if (show_only && (remove_directories ||
+			    (matches == MATCHED_EXACTLY))) {
+				printf("Would remove %s\n", qname);
+			} else if (remove_directories ||
+				   (matches == MATCHED_EXACTLY)) {
+				if (!quiet)
+					printf("Removing %s\n", qname);
+				if (remove_dir_recursively(&directory,
+							   rm_flags) != 0) {
+					warning("failed to remove '%s'", qname);
+					errors++;
+				}
+			} else if (show_only) {
+				printf("Would not remove %s\n", qname);
+			} else {
+				printf("Not removing %s\n", qname);
+			}
+			strbuf_reset(&directory);
+		} else {
+			if (pathspec && !matches)
+				continue;
+			qname = quote_path_relative(ent->name, -1, &buf, prefix);
+			if (show_only) {
+				printf("Would remove %s\n", qname);
+				continue;
+			} else if (!quiet) {
+				printf("Removing %s\n", qname);
+			}
+			if (unlink(ent->name) != 0) {
+				warning("failed to remove '%s'", qname);
+				errors++;
+			}
+		}
+	}
+	free(seen);
+
+	strbuf_release(&directory);
+	return (errors != 0);
+}
diff --git a/builtin/clone.c b/builtin/clone.c
new file mode 100644
index 0000000..58bacbd
--- /dev/null
+++ b/builtin/clone.c
@@ -0,0 +1,671 @@
+/*
+ * Builtin "git clone"
+ *
+ * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
+ *		 2008 Daniel Barkalow <barkalow@iabervon.org>
+ * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
+ *
+ * Clone a repository into a different directory that does not yet exist.
+ */
+
+#include "cache.h"
+#include "parse-options.h"
+#include "fetch-pack.h"
+#include "refs.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "unpack-trees.h"
+#include "transport.h"
+#include "strbuf.h"
+#include "dir.h"
+#include "pack-refs.h"
+#include "sigchain.h"
+#include "branch.h"
+#include "remote.h"
+#include "run-command.h"
+
+/*
+ * Overall FIXMEs:
+ *  - respect DB_ENVIRONMENT for .git/objects.
+ *
+ * Implementation notes:
+ *  - dropping use-separate-remote and no-separate-remote compatibility
+ *
+ */
+static const char * const builtin_clone_usage[] = {
+	"git clone [options] [--] <repo> [<dir>]",
+	NULL
+};
+
+static int option_quiet, option_no_checkout, option_bare, option_mirror;
+static int option_local, option_no_hardlinks, option_shared, option_recursive;
+static char *option_template, *option_reference, *option_depth;
+static char *option_origin = NULL;
+static char *option_branch = NULL;
+static char *option_upload_pack = "git-upload-pack";
+static int option_verbose;
+static int option_progress;
+
+static struct option builtin_clone_options[] = {
+	OPT__QUIET(&option_quiet),
+	OPT__VERBOSE(&option_verbose),
+	OPT_BOOLEAN(0, "progress", &option_progress,
+			"force progress reporting"),
+	OPT_BOOLEAN('n', "no-checkout", &option_no_checkout,
+		    "don't create a checkout"),
+	OPT_BOOLEAN(0, "bare", &option_bare, "create a bare repository"),
+	{ OPTION_BOOLEAN, 0, "naked", &option_bare, NULL,
+		"create a bare repository",
+		PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
+	OPT_BOOLEAN(0, "mirror", &option_mirror,
+		    "create a mirror repository (implies bare)"),
+	OPT_BOOLEAN('l', "local", &option_local,
+		    "to clone from a local repository"),
+	OPT_BOOLEAN(0, "no-hardlinks", &option_no_hardlinks,
+		    "don't use local hardlinks, always copy"),
+	OPT_BOOLEAN('s', "shared", &option_shared,
+		    "setup as shared repository"),
+	OPT_BOOLEAN(0, "recursive", &option_recursive,
+		    "initialize submodules in the clone"),
+	OPT_STRING(0, "template", &option_template, "path",
+		   "path the template repository"),
+	OPT_STRING(0, "reference", &option_reference, "repo",
+		   "reference repository"),
+	OPT_STRING('o', "origin", &option_origin, "branch",
+		   "use <branch> instead of 'origin' to track upstream"),
+	OPT_STRING('b', "branch", &option_branch, "branch",
+		   "checkout <branch> instead of the remote's HEAD"),
+	OPT_STRING('u', "upload-pack", &option_upload_pack, "path",
+		   "path to git-upload-pack on the remote"),
+	OPT_STRING(0, "depth", &option_depth, "depth",
+		    "create a shallow clone of that depth"),
+
+	OPT_END()
+};
+
+static const char *argv_submodule[] = {
+	"submodule", "update", "--init", "--recursive", NULL
+};
+
+static char *get_repo_path(const char *repo, int *is_bundle)
+{
+	static char *suffix[] = { "/.git", ".git", "" };
+	static char *bundle_suffix[] = { ".bundle", "" };
+	struct stat st;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(suffix); i++) {
+		const char *path;
+		path = mkpath("%s%s", repo, suffix[i]);
+		if (is_directory(path)) {
+			*is_bundle = 0;
+			return xstrdup(make_nonrelative_path(path));
+		}
+	}
+
+	for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
+		const char *path;
+		path = mkpath("%s%s", repo, bundle_suffix[i]);
+		if (!stat(path, &st) && S_ISREG(st.st_mode)) {
+			*is_bundle = 1;
+			return xstrdup(make_nonrelative_path(path));
+		}
+	}
+
+	return NULL;
+}
+
+static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
+{
+	const char *end = repo + strlen(repo), *start;
+	char *dir;
+
+	/*
+	 * Strip trailing spaces, slashes and /.git
+	 */
+	while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
+		end--;
+	if (end - repo > 5 && is_dir_sep(end[-5]) &&
+	    !strncmp(end - 4, ".git", 4)) {
+		end -= 5;
+		while (repo < end && is_dir_sep(end[-1]))
+			end--;
+	}
+
+	/*
+	 * Find last component, but be prepared that repo could have
+	 * the form  "remote.example.com:foo.git", i.e. no slash
+	 * in the directory part.
+	 */
+	start = end;
+	while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
+		start--;
+
+	/*
+	 * Strip .{bundle,git}.
+	 */
+	if (is_bundle) {
+		if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
+			end -= 7;
+	} else {
+		if (end - start > 4 && !strncmp(end - 4, ".git", 4))
+			end -= 4;
+	}
+
+	if (is_bare) {
+		struct strbuf result = STRBUF_INIT;
+		strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
+		dir = strbuf_detach(&result, NULL);
+	} else
+		dir = xstrndup(start, end - start);
+	/*
+	 * Replace sequences of 'control' characters and whitespace
+	 * with one ascii space, remove leading and trailing spaces.
+	 */
+	if (*dir) {
+		char *out = dir;
+		int prev_space = 1 /* strip leading whitespace */;
+		for (end = dir; *end; ++end) {
+			char ch = *end;
+			if ((unsigned char)ch < '\x20')
+				ch = '\x20';
+			if (isspace(ch)) {
+				if (prev_space)
+					continue;
+				prev_space = 1;
+			} else
+				prev_space = 0;
+			*out++ = ch;
+		}
+		*out = '\0';
+		if (out > dir && prev_space)
+			out[-1] = '\0';
+	}
+	return dir;
+}
+
+static void strip_trailing_slashes(char *dir)
+{
+	char *end = dir + strlen(dir);
+
+	while (dir < end - 1 && is_dir_sep(end[-1]))
+		end--;
+	*end = '\0';
+}
+
+static void setup_reference(const char *repo)
+{
+	const char *ref_git;
+	char *ref_git_copy;
+
+	struct remote *remote;
+	struct transport *transport;
+	const struct ref *extra;
+
+	ref_git = make_absolute_path(option_reference);
+
+	if (is_directory(mkpath("%s/.git/objects", ref_git)))
+		ref_git = mkpath("%s/.git", ref_git);
+	else if (!is_directory(mkpath("%s/objects", ref_git)))
+		die("reference repository '%s' is not a local directory.",
+		    option_reference);
+
+	ref_git_copy = xstrdup(ref_git);
+
+	add_to_alternates_file(ref_git_copy);
+
+	remote = remote_get(ref_git_copy);
+	transport = transport_get(remote, ref_git_copy);
+	for (extra = transport_get_remote_refs(transport); extra;
+	     extra = extra->next)
+		add_extra_ref(extra->name, extra->old_sha1, 0);
+
+	transport_disconnect(transport);
+
+	free(ref_git_copy);
+}
+
+static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest)
+{
+	struct dirent *de;
+	struct stat buf;
+	int src_len, dest_len;
+	DIR *dir;
+
+	dir = opendir(src->buf);
+	if (!dir)
+		die_errno("failed to open '%s'", src->buf);
+
+	if (mkdir(dest->buf, 0777)) {
+		if (errno != EEXIST)
+			die_errno("failed to create directory '%s'", dest->buf);
+		else if (stat(dest->buf, &buf))
+			die_errno("failed to stat '%s'", dest->buf);
+		else if (!S_ISDIR(buf.st_mode))
+			die("%s exists and is not a directory", dest->buf);
+	}
+
+	strbuf_addch(src, '/');
+	src_len = src->len;
+	strbuf_addch(dest, '/');
+	dest_len = dest->len;
+
+	while ((de = readdir(dir)) != NULL) {
+		strbuf_setlen(src, src_len);
+		strbuf_addstr(src, de->d_name);
+		strbuf_setlen(dest, dest_len);
+		strbuf_addstr(dest, de->d_name);
+		if (stat(src->buf, &buf)) {
+			warning ("failed to stat %s\n", src->buf);
+			continue;
+		}
+		if (S_ISDIR(buf.st_mode)) {
+			if (de->d_name[0] != '.')
+				copy_or_link_directory(src, dest);
+			continue;
+		}
+
+		if (unlink(dest->buf) && errno != ENOENT)
+			die_errno("failed to unlink '%s'", dest->buf);
+		if (!option_no_hardlinks) {
+			if (!link(src->buf, dest->buf))
+				continue;
+			if (option_local)
+				die_errno("failed to create link '%s'", dest->buf);
+			option_no_hardlinks = 1;
+		}
+		if (copy_file_with_time(dest->buf, src->buf, 0666))
+			die_errno("failed to copy file to '%s'", dest->buf);
+	}
+	closedir(dir);
+}
+
+static const struct ref *clone_local(const char *src_repo,
+				     const char *dest_repo)
+{
+	const struct ref *ret;
+	struct strbuf src = STRBUF_INIT;
+	struct strbuf dest = STRBUF_INIT;
+	struct remote *remote;
+	struct transport *transport;
+
+	if (option_shared)
+		add_to_alternates_file(src_repo);
+	else {
+		strbuf_addf(&src, "%s/objects", src_repo);
+		strbuf_addf(&dest, "%s/objects", dest_repo);
+		copy_or_link_directory(&src, &dest);
+		strbuf_release(&src);
+		strbuf_release(&dest);
+	}
+
+	remote = remote_get(src_repo);
+	transport = transport_get(remote, src_repo);
+	ret = transport_get_remote_refs(transport);
+	transport_disconnect(transport);
+	return ret;
+}
+
+static const char *junk_work_tree;
+static const char *junk_git_dir;
+static pid_t junk_pid;
+
+static void remove_junk(void)
+{
+	struct strbuf sb = STRBUF_INIT;
+	if (getpid() != junk_pid)
+		return;
+	if (junk_git_dir) {
+		strbuf_addstr(&sb, junk_git_dir);
+		remove_dir_recursively(&sb, 0);
+		strbuf_reset(&sb);
+	}
+	if (junk_work_tree) {
+		strbuf_addstr(&sb, junk_work_tree);
+		remove_dir_recursively(&sb, 0);
+		strbuf_reset(&sb);
+	}
+}
+
+static void remove_junk_on_signal(int signo)
+{
+	remove_junk();
+	sigchain_pop(signo);
+	raise(signo);
+}
+
+static struct ref *wanted_peer_refs(const struct ref *refs,
+		struct refspec *refspec)
+{
+	struct ref *local_refs = NULL;
+	struct ref **tail = &local_refs;
+
+	get_fetch_map(refs, refspec, &tail, 0);
+	if (!option_mirror)
+		get_fetch_map(refs, tag_refspec, &tail, 0);
+
+	return local_refs;
+}
+
+static void write_remote_refs(const struct ref *local_refs)
+{
+	const struct ref *r;
+
+	for (r = local_refs; r; r = r->next)
+		add_extra_ref(r->peer_ref->name, r->old_sha1, 0);
+
+	pack_refs(PACK_REFS_ALL);
+	clear_extra_refs();
+}
+
+int cmd_clone(int argc, const char **argv, const char *prefix)
+{
+	int is_bundle = 0;
+	struct stat buf;
+	const char *repo_name, *repo, *work_tree, *git_dir;
+	char *path, *dir;
+	int dest_exists;
+	const struct ref *refs, *remote_head;
+	const struct ref *remote_head_points_at;
+	const struct ref *our_head_points_at;
+	struct ref *mapped_refs;
+	struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
+	struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
+	struct transport *transport = NULL;
+	char *src_ref_prefix = "refs/heads/";
+	int err = 0;
+
+	struct refspec *refspec;
+	const char *fetch_pattern;
+
+	junk_pid = getpid();
+
+	argc = parse_options(argc, argv, prefix, builtin_clone_options,
+			     builtin_clone_usage, 0);
+
+	if (argc > 2)
+		usage_msg_opt("Too many arguments.",
+			builtin_clone_usage, builtin_clone_options);
+
+	if (argc == 0)
+		usage_msg_opt("You must specify a repository to clone.",
+			builtin_clone_usage, builtin_clone_options);
+
+	if (option_mirror)
+		option_bare = 1;
+
+	if (option_bare) {
+		if (option_origin)
+			die("--bare and --origin %s options are incompatible.",
+			    option_origin);
+		option_no_checkout = 1;
+	}
+
+	if (!option_origin)
+		option_origin = "origin";
+
+	repo_name = argv[0];
+
+	path = get_repo_path(repo_name, &is_bundle);
+	if (path)
+		repo = xstrdup(make_nonrelative_path(repo_name));
+	else if (!strchr(repo_name, ':'))
+		repo = xstrdup(make_absolute_path(repo_name));
+	else
+		repo = repo_name;
+
+	if (argc == 2)
+		dir = xstrdup(argv[1]);
+	else
+		dir = guess_dir_name(repo_name, is_bundle, option_bare);
+	strip_trailing_slashes(dir);
+
+	dest_exists = !stat(dir, &buf);
+	if (dest_exists && !is_empty_dir(dir))
+		die("destination path '%s' already exists and is not "
+			"an empty directory.", dir);
+
+	strbuf_addf(&reflog_msg, "clone: from %s", repo);
+
+	if (option_bare)
+		work_tree = NULL;
+	else {
+		work_tree = getenv("GIT_WORK_TREE");
+		if (work_tree && !stat(work_tree, &buf))
+			die("working tree '%s' already exists.", work_tree);
+	}
+
+	if (option_bare || work_tree)
+		git_dir = xstrdup(dir);
+	else {
+		work_tree = dir;
+		git_dir = xstrdup(mkpath("%s/.git", dir));
+	}
+
+	if (!option_bare) {
+		junk_work_tree = work_tree;
+		if (safe_create_leading_directories_const(work_tree) < 0)
+			die_errno("could not create leading directories of '%s'",
+				  work_tree);
+		if (!dest_exists && mkdir(work_tree, 0755))
+			die_errno("could not create work tree dir '%s'.",
+				  work_tree);
+		set_git_work_tree(work_tree);
+	}
+	junk_git_dir = git_dir;
+	atexit(remove_junk);
+	sigchain_push_common(remove_junk_on_signal);
+
+	setenv(CONFIG_ENVIRONMENT, mkpath("%s/config", git_dir), 1);
+
+	if (safe_create_leading_directories_const(git_dir) < 0)
+		die("could not create leading directories of '%s'", git_dir);
+	set_git_dir(make_absolute_path(git_dir));
+
+	init_db(option_template, option_quiet ? INIT_DB_QUIET : 0);
+
+	/*
+	 * At this point, the config exists, so we do not need the
+	 * environment variable.  We actually need to unset it, too, to
+	 * re-enable parsing of the global configs.
+	 */
+	unsetenv(CONFIG_ENVIRONMENT);
+
+	if (option_reference)
+		setup_reference(git_dir);
+
+	git_config(git_default_config, NULL);
+
+	if (option_bare) {
+		if (option_mirror)
+			src_ref_prefix = "refs/";
+		strbuf_addstr(&branch_top, src_ref_prefix);
+
+		git_config_set("core.bare", "true");
+	} else {
+		strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
+	}
+
+	strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
+
+	if (option_mirror || !option_bare) {
+		/* Configure the remote */
+		strbuf_addf(&key, "remote.%s.fetch", option_origin);
+		git_config_set_multivar(key.buf, value.buf, "^$", 0);
+		strbuf_reset(&key);
+
+		if (option_mirror) {
+			strbuf_addf(&key, "remote.%s.mirror", option_origin);
+			git_config_set(key.buf, "true");
+			strbuf_reset(&key);
+		}
+
+		strbuf_addf(&key, "remote.%s.url", option_origin);
+		git_config_set(key.buf, repo);
+		strbuf_reset(&key);
+	}
+
+	fetch_pattern = value.buf;
+	refspec = parse_fetch_refspec(1, &fetch_pattern);
+
+	strbuf_reset(&value);
+
+	if (path && !is_bundle) {
+		refs = clone_local(path, git_dir);
+		mapped_refs = wanted_peer_refs(refs, refspec);
+	} else {
+		struct remote *remote = remote_get(argv[0]);
+		transport = transport_get(remote, remote->url[0]);
+
+		if (!transport->get_refs_list || !transport->fetch)
+			die("Don't know how to clone %s", transport->url);
+
+		transport_set_option(transport, TRANS_OPT_KEEP, "yes");
+
+		if (option_depth)
+			transport_set_option(transport, TRANS_OPT_DEPTH,
+					     option_depth);
+
+		if (option_quiet)
+			transport->verbose = -1;
+		else if (option_verbose)
+			transport->verbose = 1;
+
+		if (option_progress)
+			transport->progress = 1;
+
+		if (option_upload_pack)
+			transport_set_option(transport, TRANS_OPT_UPLOADPACK,
+					     option_upload_pack);
+
+		refs = transport_get_remote_refs(transport);
+		if (refs) {
+			mapped_refs = wanted_peer_refs(refs, refspec);
+			transport_fetch_refs(transport, mapped_refs);
+		}
+	}
+
+	if (refs) {
+		clear_extra_refs();
+
+		write_remote_refs(mapped_refs);
+
+		remote_head = find_ref_by_name(refs, "HEAD");
+		remote_head_points_at =
+			guess_remote_head(remote_head, mapped_refs, 0);
+
+		if (option_branch) {
+			struct strbuf head = STRBUF_INIT;
+			strbuf_addstr(&head, src_ref_prefix);
+			strbuf_addstr(&head, option_branch);
+			our_head_points_at =
+				find_ref_by_name(mapped_refs, head.buf);
+			strbuf_release(&head);
+
+			if (!our_head_points_at) {
+				warning("Remote branch %s not found in "
+					"upstream %s, using HEAD instead",
+					option_branch, option_origin);
+				our_head_points_at = remote_head_points_at;
+			}
+		}
+		else
+			our_head_points_at = remote_head_points_at;
+	}
+	else {
+		warning("You appear to have cloned an empty repository.");
+		our_head_points_at = NULL;
+		remote_head_points_at = NULL;
+		remote_head = NULL;
+		option_no_checkout = 1;
+		if (!option_bare)
+			install_branch_config(0, "master", option_origin,
+					      "refs/heads/master");
+	}
+
+	if (remote_head_points_at && !option_bare) {
+		struct strbuf head_ref = STRBUF_INIT;
+		strbuf_addstr(&head_ref, branch_top.buf);
+		strbuf_addstr(&head_ref, "HEAD");
+		create_symref(head_ref.buf,
+			      remote_head_points_at->peer_ref->name,
+			      reflog_msg.buf);
+	}
+
+	if (our_head_points_at) {
+		/* Local default branch link */
+		create_symref("HEAD", our_head_points_at->name, NULL);
+		if (!option_bare) {
+			const char *head = skip_prefix(our_head_points_at->name,
+						       "refs/heads/");
+			update_ref(reflog_msg.buf, "HEAD",
+				   our_head_points_at->old_sha1,
+				   NULL, 0, DIE_ON_ERR);
+			install_branch_config(0, head, option_origin,
+					      our_head_points_at->name);
+		}
+	} else if (remote_head) {
+		/* Source had detached HEAD pointing somewhere. */
+		if (!option_bare) {
+			update_ref(reflog_msg.buf, "HEAD",
+				   remote_head->old_sha1,
+				   NULL, REF_NODEREF, DIE_ON_ERR);
+			our_head_points_at = remote_head;
+		}
+	} else {
+		/* Nothing to checkout out */
+		if (!option_no_checkout)
+			warning("remote HEAD refers to nonexistent ref, "
+				"unable to checkout.\n");
+		option_no_checkout = 1;
+	}
+
+	if (transport) {
+		transport_unlock_pack(transport);
+		transport_disconnect(transport);
+	}
+
+	if (!option_no_checkout) {
+		struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
+		struct unpack_trees_options opts;
+		struct tree *tree;
+		struct tree_desc t;
+		int fd;
+
+		/* We need to be in the new work tree for the checkout */
+		setup_work_tree();
+
+		fd = hold_locked_index(lock_file, 1);
+
+		memset(&opts, 0, sizeof opts);
+		opts.update = 1;
+		opts.merge = 1;
+		opts.fn = oneway_merge;
+		opts.verbose_update = !option_quiet;
+		opts.src_index = &the_index;
+		opts.dst_index = &the_index;
+
+		tree = parse_tree_indirect(our_head_points_at->old_sha1);
+		parse_tree(tree);
+		init_tree_desc(&t, tree->buffer, tree->size);
+		unpack_trees(1, &t, &opts);
+
+		if (write_cache(fd, active_cache, active_nr) ||
+		    commit_locked_index(lock_file))
+			die("unable to write new index file");
+
+		err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
+				sha1_to_hex(our_head_points_at->old_sha1), "1",
+				NULL);
+
+		if (!err && option_recursive)
+			err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
+	}
+
+	strbuf_release(&reflog_msg);
+	strbuf_release(&branch_top);
+	strbuf_release(&key);
+	strbuf_release(&value);
+	junk_pid = 0;
+	return err;
+}
diff --git a/builtin/commit-tree.c b/builtin/commit-tree.c
new file mode 100644
index 0000000..90dac34
--- /dev/null
+++ b/builtin/commit-tree.c
@@ -0,0 +1,133 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "commit.h"
+#include "tree.h"
+#include "builtin.h"
+#include "utf8.h"
+
+/*
+ * FIXME! Share the code with "write-tree.c"
+ */
+static void check_valid(unsigned char *sha1, enum object_type expect)
+{
+	enum object_type type = sha1_object_info(sha1, NULL);
+	if (type < 0)
+		die("%s is not a valid object", sha1_to_hex(sha1));
+	if (type != expect)
+		die("%s is not a valid '%s' object", sha1_to_hex(sha1),
+		    typename(expect));
+}
+
+static const char commit_tree_usage[] = "git commit-tree <sha1> [-p <sha1>]* < changelog";
+
+static void new_parent(struct commit *parent, struct commit_list **parents_p)
+{
+	unsigned char *sha1 = parent->object.sha1;
+	struct commit_list *parents;
+	for (parents = *parents_p; parents; parents = parents->next) {
+		if (parents->item == parent) {
+			error("duplicate parent %s ignored", sha1_to_hex(sha1));
+			return;
+		}
+		parents_p = &parents->next;
+	}
+	commit_list_insert(parent, parents_p);
+}
+
+static const char commit_utf8_warn[] =
+"Warning: commit message does not conform to UTF-8.\n"
+"You may want to amend it after fixing the message, or set the config\n"
+"variable i18n.commitencoding to the encoding your project uses.\n";
+
+int commit_tree(const char *msg, unsigned char *tree,
+		struct commit_list *parents, unsigned char *ret,
+		const char *author)
+{
+	int result;
+	int encoding_is_utf8;
+	struct strbuf buffer;
+
+	check_valid(tree, OBJ_TREE);
+
+	/* Not having i18n.commitencoding is the same as having utf-8 */
+	encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
+
+	strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
+	strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
+
+	/*
+	 * NOTE! This ordering means that the same exact tree merged with a
+	 * different order of parents will be a _different_ changeset even
+	 * if everything else stays the same.
+	 */
+	while (parents) {
+		struct commit_list *next = parents->next;
+		strbuf_addf(&buffer, "parent %s\n",
+			sha1_to_hex(parents->item->object.sha1));
+		free(parents);
+		parents = next;
+	}
+
+	/* Person/date information */
+	if (!author)
+		author = git_author_info(IDENT_ERROR_ON_NO_NAME);
+	strbuf_addf(&buffer, "author %s\n", author);
+	strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
+	if (!encoding_is_utf8)
+		strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
+	strbuf_addch(&buffer, '\n');
+
+	/* And add the comment */
+	strbuf_addstr(&buffer, msg);
+
+	/* And check the encoding */
+	if (encoding_is_utf8 && !is_utf8(buffer.buf))
+		fprintf(stderr, commit_utf8_warn);
+
+	result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
+	strbuf_release(&buffer);
+	return result;
+}
+
+int cmd_commit_tree(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	struct commit_list *parents = NULL;
+	unsigned char tree_sha1[20];
+	unsigned char commit_sha1[20];
+	struct strbuf buffer = STRBUF_INIT;
+
+	git_config(git_default_config, NULL);
+
+	if (argc < 2 || !strcmp(argv[1], "-h"))
+		usage(commit_tree_usage);
+	if (get_sha1(argv[1], tree_sha1))
+		die("Not a valid object name %s", argv[1]);
+
+	for (i = 2; i < argc; i += 2) {
+		unsigned char sha1[20];
+		const char *a, *b;
+		a = argv[i]; b = argv[i+1];
+		if (!b || strcmp(a, "-p"))
+			usage(commit_tree_usage);
+
+		if (get_sha1(b, sha1))
+			die("Not a valid object name %s", b);
+		check_valid(sha1, OBJ_COMMIT);
+		new_parent(lookup_commit(sha1), &parents);
+	}
+
+	if (strbuf_read(&buffer, 0, 0) < 0)
+		die_errno("git commit-tree: failed to read");
+
+	if (!commit_tree(buffer.buf, tree_sha1, parents, commit_sha1, NULL)) {
+		printf("%s\n", sha1_to_hex(commit_sha1));
+		return 0;
+	}
+	else
+		return 1;
+}
diff --git a/builtin/commit.c b/builtin/commit.c
new file mode 100644
index 0000000..f4c7344
--- /dev/null
+++ b/builtin/commit.c
@@ -0,0 +1,1310 @@
+/*
+ * Builtin "git commit"
+ *
+ * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>
+ * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
+ */
+
+#include "cache.h"
+#include "cache-tree.h"
+#include "color.h"
+#include "dir.h"
+#include "builtin.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "commit.h"
+#include "revision.h"
+#include "wt-status.h"
+#include "run-command.h"
+#include "refs.h"
+#include "log-tree.h"
+#include "strbuf.h"
+#include "utf8.h"
+#include "parse-options.h"
+#include "string-list.h"
+#include "rerere.h"
+#include "unpack-trees.h"
+#include "quote.h"
+
+static const char * const builtin_commit_usage[] = {
+	"git commit [options] [--] <filepattern>...",
+	NULL
+};
+
+static const char * const builtin_status_usage[] = {
+	"git status [options] [--] <filepattern>...",
+	NULL
+};
+
+static const char implicit_ident_advice[] =
+"Your name and email address were configured automatically based\n"
+"on your username and hostname. Please check that they are accurate.\n"
+"You can suppress this message by setting them explicitly:\n"
+"\n"
+"    git config --global user.name \"Your Name\"\n"
+"    git config --global user.email you@example.com\n"
+"\n"
+"If the identity used for this commit is wrong, you can fix it with:\n"
+"\n"
+"    git commit --amend --author='Your Name <you@example.com>'\n";
+
+static unsigned char head_sha1[20];
+
+static char *use_message_buffer;
+static const char commit_editmsg[] = "COMMIT_EDITMSG";
+static struct lock_file index_lock; /* real index */
+static struct lock_file false_lock; /* used only for partial commits */
+static enum {
+	COMMIT_AS_IS = 1,
+	COMMIT_NORMAL,
+	COMMIT_PARTIAL,
+} commit_style;
+
+static const char *logfile, *force_author;
+static const char *template_file;
+static char *edit_message, *use_message;
+static char *author_name, *author_email, *author_date;
+static int all, edit_flag, also, interactive, only, amend, signoff;
+static int quiet, verbose, no_verify, allow_empty, dry_run, renew_authorship;
+static char *untracked_files_arg, *force_date;
+/*
+ * The default commit message cleanup mode will remove the lines
+ * beginning with # (shell comments) and leading and trailing
+ * whitespaces (empty lines or containing only whitespaces)
+ * if editor is used, and only the whitespaces if the message
+ * is specified explicitly.
+ */
+static enum {
+	CLEANUP_SPACE,
+	CLEANUP_NONE,
+	CLEANUP_ALL,
+} cleanup_mode;
+static char *cleanup_arg;
+
+static int use_editor = 1, initial_commit, in_merge, include_status = 1;
+static const char *only_include_assumed;
+static struct strbuf message;
+
+static int null_termination;
+static enum {
+	STATUS_FORMAT_LONG,
+	STATUS_FORMAT_SHORT,
+	STATUS_FORMAT_PORCELAIN,
+} status_format = STATUS_FORMAT_LONG;
+
+static int opt_parse_m(const struct option *opt, const char *arg, int unset)
+{
+	struct strbuf *buf = opt->value;
+	if (unset)
+		strbuf_setlen(buf, 0);
+	else {
+		strbuf_addstr(buf, arg);
+		strbuf_addstr(buf, "\n\n");
+	}
+	return 0;
+}
+
+static struct option builtin_commit_options[] = {
+	OPT__QUIET(&quiet),
+	OPT__VERBOSE(&verbose),
+
+	OPT_GROUP("Commit message options"),
+	OPT_FILENAME('F', "file", &logfile, "read log from file"),
+	OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
+	OPT_STRING(0, "date", &force_date, "DATE", "override date for commit"),
+	OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
+	OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit"),
+	OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
+	OPT_BOOLEAN(0, "reset-author", &renew_authorship, "the commit is authored by me now (used with -C-c/--amend)"),
+	OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
+	OPT_FILENAME('t', "template", &template_file, "use specified template file"),
+	OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
+	OPT_STRING(0, "cleanup", &cleanup_arg, "default", "how to strip spaces and #comments from message"),
+	OPT_BOOLEAN(0, "status", &include_status, "include status in commit message template"),
+	/* end commit message options */
+
+	OPT_GROUP("Commit contents options"),
+	OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
+	OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
+	OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
+	OPT_BOOLEAN('o', "only", &only, "commit only specified files"),
+	OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
+	OPT_BOOLEAN(0, "dry-run", &dry_run, "show what would be committed"),
+	OPT_SET_INT(0, "short", &status_format, "show status concisely",
+		    STATUS_FORMAT_SHORT),
+	OPT_SET_INT(0, "porcelain", &status_format,
+		    "show porcelain output format", STATUS_FORMAT_PORCELAIN),
+	OPT_BOOLEAN('z', "null", &null_termination,
+		    "terminate entries with NUL"),
+	OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
+	{ OPTION_STRING, 'u', "untracked-files", &untracked_files_arg, "mode", "show untracked files, optional modes: all, normal, no. (Default: all)", PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
+	OPT_BOOLEAN(0, "allow-empty", &allow_empty, "ok to record an empty change"),
+	/* end commit contents options */
+
+	OPT_END()
+};
+
+static void rollback_index_files(void)
+{
+	switch (commit_style) {
+	case COMMIT_AS_IS:
+		break; /* nothing to do */
+	case COMMIT_NORMAL:
+		rollback_lock_file(&index_lock);
+		break;
+	case COMMIT_PARTIAL:
+		rollback_lock_file(&index_lock);
+		rollback_lock_file(&false_lock);
+		break;
+	}
+}
+
+static int commit_index_files(void)
+{
+	int err = 0;
+
+	switch (commit_style) {
+	case COMMIT_AS_IS:
+		break; /* nothing to do */
+	case COMMIT_NORMAL:
+		err = commit_lock_file(&index_lock);
+		break;
+	case COMMIT_PARTIAL:
+		err = commit_lock_file(&index_lock);
+		rollback_lock_file(&false_lock);
+		break;
+	}
+
+	return err;
+}
+
+/*
+ * Take a union of paths in the index and the named tree (typically, "HEAD"),
+ * and return the paths that match the given pattern in list.
+ */
+static int list_paths(struct string_list *list, const char *with_tree,
+		      const char *prefix, const char **pattern)
+{
+	int i;
+	char *m;
+
+	for (i = 0; pattern[i]; i++)
+		;
+	m = xcalloc(1, i);
+
+	if (with_tree)
+		overlay_tree_on_cache(with_tree, prefix);
+
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		struct string_list_item *item;
+
+		if (ce->ce_flags & CE_UPDATE)
+			continue;
+		if (!match_pathspec(pattern, ce->name, ce_namelen(ce), 0, m))
+			continue;
+		item = string_list_insert(ce->name, list);
+		if (ce_skip_worktree(ce))
+			item->util = item; /* better a valid pointer than a fake one */
+	}
+
+	return report_path_error(m, pattern, prefix ? strlen(prefix) : 0);
+}
+
+static void add_remove_files(struct string_list *list)
+{
+	int i;
+	for (i = 0; i < list->nr; i++) {
+		struct stat st;
+		struct string_list_item *p = &(list->items[i]);
+
+		/* p->util is skip-worktree */
+		if (p->util)
+			continue;
+
+		if (!lstat(p->string, &st)) {
+			if (add_to_cache(p->string, &st, 0))
+				die("updating files failed");
+		} else
+			remove_file_from_cache(p->string);
+	}
+}
+
+static void create_base_index(void)
+{
+	struct tree *tree;
+	struct unpack_trees_options opts;
+	struct tree_desc t;
+
+	if (initial_commit) {
+		discard_cache();
+		return;
+	}
+
+	memset(&opts, 0, sizeof(opts));
+	opts.head_idx = 1;
+	opts.index_only = 1;
+	opts.merge = 1;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
+
+	opts.fn = oneway_merge;
+	tree = parse_tree_indirect(head_sha1);
+	if (!tree)
+		die("failed to unpack HEAD tree object");
+	parse_tree(tree);
+	init_tree_desc(&t, tree->buffer, tree->size);
+	if (unpack_trees(1, &t, &opts))
+		exit(128); /* We've already reported the error, finish dying */
+}
+
+static void refresh_cache_or_die(int refresh_flags)
+{
+	/*
+	 * refresh_flags contains REFRESH_QUIET, so the only errors
+	 * are for unmerged entries.
+	 */
+	if (refresh_cache(refresh_flags | REFRESH_IN_PORCELAIN))
+		die_resolve_conflict("commit");
+}
+
+static char *prepare_index(int argc, const char **argv, const char *prefix, int is_status)
+{
+	int fd;
+	struct string_list partial;
+	const char **pathspec = NULL;
+	int refresh_flags = REFRESH_QUIET;
+
+	if (is_status)
+		refresh_flags |= REFRESH_UNMERGED;
+	if (interactive) {
+		if (interactive_add(argc, argv, prefix) != 0)
+			die("interactive add failed");
+		if (read_cache_preload(NULL) < 0)
+			die("index file corrupt");
+		commit_style = COMMIT_AS_IS;
+		return get_index_file();
+	}
+
+	if (*argv)
+		pathspec = get_pathspec(prefix, argv);
+
+	if (read_cache_preload(pathspec) < 0)
+		die("index file corrupt");
+
+	/*
+	 * Non partial, non as-is commit.
+	 *
+	 * (1) get the real index;
+	 * (2) update the_index as necessary;
+	 * (3) write the_index out to the real index (still locked);
+	 * (4) return the name of the locked index file.
+	 *
+	 * The caller should run hooks on the locked real index, and
+	 * (A) if all goes well, commit the real index;
+	 * (B) on failure, rollback the real index.
+	 */
+	if (all || (also && pathspec && *pathspec)) {
+		int fd = hold_locked_index(&index_lock, 1);
+		add_files_to_cache(also ? prefix : NULL, pathspec, 0);
+		refresh_cache_or_die(refresh_flags);
+		if (write_cache(fd, active_cache, active_nr) ||
+		    close_lock_file(&index_lock))
+			die("unable to write new_index file");
+		commit_style = COMMIT_NORMAL;
+		return index_lock.filename;
+	}
+
+	/*
+	 * As-is commit.
+	 *
+	 * (1) return the name of the real index file.
+	 *
+	 * The caller should run hooks on the real index, and run
+	 * hooks on the real index, and create commit from the_index.
+	 * We still need to refresh the index here.
+	 */
+	if (!pathspec || !*pathspec) {
+		fd = hold_locked_index(&index_lock, 1);
+		refresh_cache_or_die(refresh_flags);
+		if (write_cache(fd, active_cache, active_nr) ||
+		    commit_locked_index(&index_lock))
+			die("unable to write new_index file");
+		commit_style = COMMIT_AS_IS;
+		return get_index_file();
+	}
+
+	/*
+	 * A partial commit.
+	 *
+	 * (0) find the set of affected paths;
+	 * (1) get lock on the real index file;
+	 * (2) update the_index with the given paths;
+	 * (3) write the_index out to the real index (still locked);
+	 * (4) get lock on the false index file;
+	 * (5) reset the_index from HEAD;
+	 * (6) update the_index the same way as (2);
+	 * (7) write the_index out to the false index file;
+	 * (8) return the name of the false index file (still locked);
+	 *
+	 * The caller should run hooks on the locked false index, and
+	 * create commit from it.  Then
+	 * (A) if all goes well, commit the real index;
+	 * (B) on failure, rollback the real index;
+	 * In either case, rollback the false index.
+	 */
+	commit_style = COMMIT_PARTIAL;
+
+	if (in_merge)
+		die("cannot do a partial commit during a merge.");
+
+	memset(&partial, 0, sizeof(partial));
+	partial.strdup_strings = 1;
+	if (list_paths(&partial, initial_commit ? NULL : "HEAD", prefix, pathspec))
+		exit(1);
+
+	discard_cache();
+	if (read_cache() < 0)
+		die("cannot read the index");
+
+	fd = hold_locked_index(&index_lock, 1);
+	add_remove_files(&partial);
+	refresh_cache(REFRESH_QUIET);
+	if (write_cache(fd, active_cache, active_nr) ||
+	    close_lock_file(&index_lock))
+		die("unable to write new_index file");
+
+	fd = hold_lock_file_for_update(&false_lock,
+				       git_path("next-index-%"PRIuMAX,
+						(uintmax_t) getpid()),
+				       LOCK_DIE_ON_ERROR);
+
+	create_base_index();
+	add_remove_files(&partial);
+	refresh_cache(REFRESH_QUIET);
+
+	if (write_cache(fd, active_cache, active_nr) ||
+	    close_lock_file(&false_lock))
+		die("unable to write temporary index file");
+
+	discard_cache();
+	read_cache_from(false_lock.filename);
+
+	return false_lock.filename;
+}
+
+static int run_status(FILE *fp, const char *index_file, const char *prefix, int nowarn,
+		      struct wt_status *s)
+{
+	unsigned char sha1[20];
+
+	if (s->relative_paths)
+		s->prefix = prefix;
+
+	if (amend) {
+		s->amend = 1;
+		s->reference = "HEAD^1";
+	}
+	s->verbose = verbose;
+	s->index_file = index_file;
+	s->fp = fp;
+	s->nowarn = nowarn;
+	s->is_initial = get_sha1(s->reference, sha1) ? 1 : 0;
+
+	wt_status_collect(s);
+
+	switch (status_format) {
+	case STATUS_FORMAT_SHORT:
+		wt_shortstatus_print(s, null_termination);
+		break;
+	case STATUS_FORMAT_PORCELAIN:
+		wt_porcelain_print(s, null_termination);
+		break;
+	case STATUS_FORMAT_LONG:
+		wt_status_print(s);
+		break;
+	}
+
+	return s->commitable;
+}
+
+static int is_a_merge(const unsigned char *sha1)
+{
+	struct commit *commit = lookup_commit(sha1);
+	if (!commit || parse_commit(commit))
+		die("could not parse HEAD commit");
+	return !!(commit->parents && commit->parents->next);
+}
+
+static const char sign_off_header[] = "Signed-off-by: ";
+
+static void determine_author_info(void)
+{
+	char *name, *email, *date;
+
+	name = getenv("GIT_AUTHOR_NAME");
+	email = getenv("GIT_AUTHOR_EMAIL");
+	date = getenv("GIT_AUTHOR_DATE");
+
+	if (use_message && !renew_authorship) {
+		const char *a, *lb, *rb, *eol;
+
+		a = strstr(use_message_buffer, "\nauthor ");
+		if (!a)
+			die("invalid commit: %s", use_message);
+
+		lb = strstr(a + 8, " <");
+		rb = strstr(a + 8, "> ");
+		eol = strchr(a + 8, '\n');
+		if (!lb || !rb || !eol)
+			die("invalid commit: %s", use_message);
+
+		name = xstrndup(a + 8, lb - (a + 8));
+		email = xstrndup(lb + 2, rb - (lb + 2));
+		date = xstrndup(rb + 2, eol - (rb + 2));
+	}
+
+	if (force_author) {
+		const char *lb = strstr(force_author, " <");
+		const char *rb = strchr(force_author, '>');
+
+		if (!lb || !rb)
+			die("malformed --author parameter");
+		name = xstrndup(force_author, lb - force_author);
+		email = xstrndup(lb + 2, rb - (lb + 2));
+	}
+
+	if (force_date)
+		date = force_date;
+
+	author_name = name;
+	author_email = email;
+	author_date = date;
+}
+
+static int ends_rfc2822_footer(struct strbuf *sb)
+{
+	int ch;
+	int hit = 0;
+	int i, j, k;
+	int len = sb->len;
+	int first = 1;
+	const char *buf = sb->buf;
+
+	for (i = len - 1; i > 0; i--) {
+		if (hit && buf[i] == '\n')
+			break;
+		hit = (buf[i] == '\n');
+	}
+
+	while (i < len - 1 && buf[i] == '\n')
+		i++;
+
+	for (; i < len; i = k) {
+		for (k = i; k < len && buf[k] != '\n'; k++)
+			; /* do nothing */
+		k++;
+
+		if ((buf[k] == ' ' || buf[k] == '\t') && !first)
+			continue;
+
+		first = 0;
+
+		for (j = 0; i + j < len; j++) {
+			ch = buf[i + j];
+			if (ch == ':')
+				break;
+			if (isalnum(ch) ||
+			    (ch == '-'))
+				continue;
+			return 0;
+		}
+	}
+	return 1;
+}
+
+static int prepare_to_commit(const char *index_file, const char *prefix,
+			     struct wt_status *s)
+{
+	struct stat statbuf;
+	int commitable, saved_color_setting;
+	struct strbuf sb = STRBUF_INIT;
+	char *buffer;
+	FILE *fp;
+	const char *hook_arg1 = NULL;
+	const char *hook_arg2 = NULL;
+	int ident_shown = 0;
+
+	if (!no_verify && run_hook(index_file, "pre-commit", NULL))
+		return 0;
+
+	if (message.len) {
+		strbuf_addbuf(&sb, &message);
+		hook_arg1 = "message";
+	} else if (logfile && !strcmp(logfile, "-")) {
+		if (isatty(0))
+			fprintf(stderr, "(reading log message from standard input)\n");
+		if (strbuf_read(&sb, 0, 0) < 0)
+			die_errno("could not read log from standard input");
+		hook_arg1 = "message";
+	} else if (logfile) {
+		if (strbuf_read_file(&sb, logfile, 0) < 0)
+			die_errno("could not read log file '%s'",
+				  logfile);
+		hook_arg1 = "message";
+	} else if (use_message) {
+		buffer = strstr(use_message_buffer, "\n\n");
+		if (!buffer || buffer[2] == '\0')
+			die("commit has empty message");
+		strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
+		hook_arg1 = "commit";
+		hook_arg2 = use_message;
+	} else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
+		if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
+			die_errno("could not read MERGE_MSG");
+		hook_arg1 = "merge";
+	} else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
+		if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
+			die_errno("could not read SQUASH_MSG");
+		hook_arg1 = "squash";
+	} else if (template_file && !stat(template_file, &statbuf)) {
+		if (strbuf_read_file(&sb, template_file, 0) < 0)
+			die_errno("could not read '%s'", template_file);
+		hook_arg1 = "template";
+	}
+
+	/*
+	 * This final case does not modify the template message,
+	 * it just sets the argument to the prepare-commit-msg hook.
+	 */
+	else if (in_merge)
+		hook_arg1 = "merge";
+
+	fp = fopen(git_path(commit_editmsg), "w");
+	if (fp == NULL)
+		die_errno("could not open '%s'", git_path(commit_editmsg));
+
+	if (cleanup_mode != CLEANUP_NONE)
+		stripspace(&sb, 0);
+
+	if (signoff) {
+		struct strbuf sob = STRBUF_INIT;
+		int i;
+
+		strbuf_addstr(&sob, sign_off_header);
+		strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
+					     getenv("GIT_COMMITTER_EMAIL")));
+		strbuf_addch(&sob, '\n');
+		for (i = sb.len - 1; i > 0 && sb.buf[i - 1] != '\n'; i--)
+			; /* do nothing */
+		if (prefixcmp(sb.buf + i, sob.buf)) {
+			if (!i || !ends_rfc2822_footer(&sb))
+				strbuf_addch(&sb, '\n');
+			strbuf_addbuf(&sb, &sob);
+		}
+		strbuf_release(&sob);
+	}
+
+	if (fwrite(sb.buf, 1, sb.len, fp) < sb.len)
+		die_errno("could not write commit template");
+
+	strbuf_release(&sb);
+
+	determine_author_info();
+
+	/* This checks if committer ident is explicitly given */
+	git_committer_info(0);
+	if (use_editor && include_status) {
+		char *author_ident;
+		const char *committer_ident;
+
+		if (in_merge)
+			fprintf(fp,
+				"#\n"
+				"# It looks like you may be committing a MERGE.\n"
+				"# If this is not correct, please remove the file\n"
+				"#	%s\n"
+				"# and try again.\n"
+				"#\n",
+				git_path("MERGE_HEAD"));
+
+		fprintf(fp,
+			"\n"
+			"# Please enter the commit message for your changes.");
+		if (cleanup_mode == CLEANUP_ALL)
+			fprintf(fp,
+				" Lines starting\n"
+				"# with '#' will be ignored, and an empty"
+				" message aborts the commit.\n");
+		else /* CLEANUP_SPACE, that is. */
+			fprintf(fp,
+				" Lines starting\n"
+				"# with '#' will be kept; you may remove them"
+				" yourself if you want to.\n"
+				"# An empty message aborts the commit.\n");
+		if (only_include_assumed)
+			fprintf(fp, "# %s\n", only_include_assumed);
+
+		author_ident = xstrdup(fmt_name(author_name, author_email));
+		committer_ident = fmt_name(getenv("GIT_COMMITTER_NAME"),
+					   getenv("GIT_COMMITTER_EMAIL"));
+		if (strcmp(author_ident, committer_ident))
+			fprintf(fp,
+				"%s"
+				"# Author:    %s\n",
+				ident_shown++ ? "" : "#\n",
+				author_ident);
+		free(author_ident);
+
+		if (!user_ident_sufficiently_given())
+			fprintf(fp,
+				"%s"
+				"# Committer: %s\n",
+				ident_shown++ ? "" : "#\n",
+				committer_ident);
+
+		if (ident_shown)
+			fprintf(fp, "#\n");
+
+		saved_color_setting = s->use_color;
+		s->use_color = 0;
+		commitable = run_status(fp, index_file, prefix, 1, s);
+		s->use_color = saved_color_setting;
+	} else {
+		unsigned char sha1[20];
+		const char *parent = "HEAD";
+
+		if (!active_nr && read_cache() < 0)
+			die("Cannot read index");
+
+		if (amend)
+			parent = "HEAD^1";
+
+		if (get_sha1(parent, sha1))
+			commitable = !!active_nr;
+		else
+			commitable = index_differs_from(parent, 0);
+	}
+
+	fclose(fp);
+
+	if (!commitable && !in_merge && !allow_empty &&
+	    !(amend && is_a_merge(head_sha1))) {
+		run_status(stdout, index_file, prefix, 0, s);
+		return 0;
+	}
+
+	/*
+	 * Re-read the index as pre-commit hook could have updated it,
+	 * and write it out as a tree.  We must do this before we invoke
+	 * the editor and after we invoke run_status above.
+	 */
+	discard_cache();
+	read_cache_from(index_file);
+	if (!active_cache_tree)
+		active_cache_tree = cache_tree();
+	if (cache_tree_update(active_cache_tree,
+			      active_cache, active_nr, 0, 0) < 0) {
+		error("Error building trees");
+		return 0;
+	}
+
+	if (run_hook(index_file, "prepare-commit-msg",
+		     git_path(commit_editmsg), hook_arg1, hook_arg2, NULL))
+		return 0;
+
+	if (use_editor) {
+		char index[PATH_MAX];
+		const char *env[2] = { index, NULL };
+		snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
+		if (launch_editor(git_path(commit_editmsg), NULL, env)) {
+			fprintf(stderr,
+			"Please supply the message using either -m or -F option.\n");
+			exit(1);
+		}
+	}
+
+	if (!no_verify &&
+	    run_hook(index_file, "commit-msg", git_path(commit_editmsg), NULL)) {
+		return 0;
+	}
+
+	return 1;
+}
+
+/*
+ * Find out if the message in the strbuf contains only whitespace and
+ * Signed-off-by lines.
+ */
+static int message_is_empty(struct strbuf *sb)
+{
+	struct strbuf tmpl = STRBUF_INIT;
+	const char *nl;
+	int eol, i, start = 0;
+
+	if (cleanup_mode == CLEANUP_NONE && sb->len)
+		return 0;
+
+	/* See if the template is just a prefix of the message. */
+	if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
+		stripspace(&tmpl, cleanup_mode == CLEANUP_ALL);
+		if (start + tmpl.len <= sb->len &&
+		    memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
+			start += tmpl.len;
+	}
+	strbuf_release(&tmpl);
+
+	/* Check if the rest is just whitespace and Signed-of-by's. */
+	for (i = start; i < sb->len; i++) {
+		nl = memchr(sb->buf + i, '\n', sb->len - i);
+		if (nl)
+			eol = nl - sb->buf;
+		else
+			eol = sb->len;
+
+		if (strlen(sign_off_header) <= eol - i &&
+		    !prefixcmp(sb->buf + i, sign_off_header)) {
+			i = eol;
+			continue;
+		}
+		while (i < eol)
+			if (!isspace(sb->buf[i++]))
+				return 0;
+	}
+
+	return 1;
+}
+
+static const char *find_author_by_nickname(const char *name)
+{
+	struct rev_info revs;
+	struct commit *commit;
+	struct strbuf buf = STRBUF_INIT;
+	const char *av[20];
+	int ac = 0;
+
+	init_revisions(&revs, NULL);
+	strbuf_addf(&buf, "--author=%s", name);
+	av[++ac] = "--all";
+	av[++ac] = "-i";
+	av[++ac] = buf.buf;
+	av[++ac] = NULL;
+	setup_revisions(ac, av, &revs, NULL);
+	prepare_revision_walk(&revs);
+	commit = get_revision(&revs);
+	if (commit) {
+		struct pretty_print_context ctx = {0};
+		ctx.date_mode = DATE_NORMAL;
+		strbuf_release(&buf);
+		format_commit_message(commit, "%an <%ae>", &buf, &ctx);
+		return strbuf_detach(&buf, NULL);
+	}
+	die("No existing author found with '%s'", name);
+}
+
+
+static void handle_untracked_files_arg(struct wt_status *s)
+{
+	if (!untracked_files_arg)
+		; /* default already initialized */
+	else if (!strcmp(untracked_files_arg, "no"))
+		s->show_untracked_files = SHOW_NO_UNTRACKED_FILES;
+	else if (!strcmp(untracked_files_arg, "normal"))
+		s->show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
+	else if (!strcmp(untracked_files_arg, "all"))
+		s->show_untracked_files = SHOW_ALL_UNTRACKED_FILES;
+	else
+		die("Invalid untracked files mode '%s'", untracked_files_arg);
+}
+
+static int parse_and_validate_options(int argc, const char *argv[],
+				      const char * const usage[],
+				      const char *prefix,
+				      struct wt_status *s)
+{
+	int f = 0;
+
+	argc = parse_options(argc, argv, prefix, builtin_commit_options, usage,
+			     0);
+
+	if (force_author && !strchr(force_author, '>'))
+		force_author = find_author_by_nickname(force_author);
+
+	if (force_author && renew_authorship)
+		die("Using both --reset-author and --author does not make sense");
+
+	if (logfile || message.len || use_message)
+		use_editor = 0;
+	if (edit_flag)
+		use_editor = 1;
+	if (!use_editor)
+		setenv("GIT_EDITOR", ":", 1);
+
+	if (get_sha1("HEAD", head_sha1))
+		initial_commit = 1;
+
+	/* Sanity check options */
+	if (amend && initial_commit)
+		die("You have nothing to amend.");
+	if (amend && in_merge)
+		die("You are in the middle of a merge -- cannot amend.");
+
+	if (use_message)
+		f++;
+	if (edit_message)
+		f++;
+	if (logfile)
+		f++;
+	if (f > 1)
+		die("Only one of -c/-C/-F can be used.");
+	if (message.len && f > 0)
+		die("Option -m cannot be combined with -c/-C/-F.");
+	if (edit_message)
+		use_message = edit_message;
+	if (amend && !use_message)
+		use_message = "HEAD";
+	if (!use_message && renew_authorship)
+		die("--reset-author can be used only with -C, -c or --amend.");
+	if (use_message) {
+		unsigned char sha1[20];
+		static char utf8[] = "UTF-8";
+		const char *out_enc;
+		char *enc, *end;
+		struct commit *commit;
+
+		if (get_sha1(use_message, sha1))
+			die("could not lookup commit %s", use_message);
+		commit = lookup_commit_reference(sha1);
+		if (!commit || parse_commit(commit))
+			die("could not parse commit %s", use_message);
+
+		enc = strstr(commit->buffer, "\nencoding");
+		if (enc) {
+			end = strchr(enc + 10, '\n');
+			enc = xstrndup(enc + 10, end - (enc + 10));
+		} else {
+			enc = utf8;
+		}
+		out_enc = git_commit_encoding ? git_commit_encoding : utf8;
+
+		if (strcmp(out_enc, enc))
+			use_message_buffer =
+				reencode_string(commit->buffer, out_enc, enc);
+
+		/*
+		 * If we failed to reencode the buffer, just copy it
+		 * byte for byte so the user can try to fix it up.
+		 * This also handles the case where input and output
+		 * encodings are identical.
+		 */
+		if (use_message_buffer == NULL)
+			use_message_buffer = xstrdup(commit->buffer);
+		if (enc != utf8)
+			free(enc);
+	}
+
+	if (!!also + !!only + !!all + !!interactive > 1)
+		die("Only one of --include/--only/--all/--interactive can be used.");
+	if (argc == 0 && (also || (only && !amend)))
+		die("No paths with --include/--only does not make sense.");
+	if (argc == 0 && only && amend)
+		only_include_assumed = "Clever... amending the last one with dirty index.";
+	if (argc > 0 && !also && !only)
+		only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
+	if (!cleanup_arg || !strcmp(cleanup_arg, "default"))
+		cleanup_mode = use_editor ? CLEANUP_ALL : CLEANUP_SPACE;
+	else if (!strcmp(cleanup_arg, "verbatim"))
+		cleanup_mode = CLEANUP_NONE;
+	else if (!strcmp(cleanup_arg, "whitespace"))
+		cleanup_mode = CLEANUP_SPACE;
+	else if (!strcmp(cleanup_arg, "strip"))
+		cleanup_mode = CLEANUP_ALL;
+	else
+		die("Invalid cleanup mode %s", cleanup_arg);
+
+	handle_untracked_files_arg(s);
+
+	if (all && argc > 0)
+		die("Paths with -a does not make sense.");
+	else if (interactive && argc > 0)
+		die("Paths with --interactive does not make sense.");
+
+	if (null_termination && status_format == STATUS_FORMAT_LONG)
+		status_format = STATUS_FORMAT_PORCELAIN;
+	if (status_format != STATUS_FORMAT_LONG)
+		dry_run = 1;
+
+	return argc;
+}
+
+static int dry_run_commit(int argc, const char **argv, const char *prefix,
+			  struct wt_status *s)
+{
+	int commitable;
+	const char *index_file;
+
+	index_file = prepare_index(argc, argv, prefix, 1);
+	commitable = run_status(stdout, index_file, prefix, 0, s);
+	rollback_index_files();
+
+	return commitable ? 0 : 1;
+}
+
+static int parse_status_slot(const char *var, int offset)
+{
+	if (!strcasecmp(var+offset, "header"))
+		return WT_STATUS_HEADER;
+	if (!strcasecmp(var+offset, "updated")
+		|| !strcasecmp(var+offset, "added"))
+		return WT_STATUS_UPDATED;
+	if (!strcasecmp(var+offset, "changed"))
+		return WT_STATUS_CHANGED;
+	if (!strcasecmp(var+offset, "untracked"))
+		return WT_STATUS_UNTRACKED;
+	if (!strcasecmp(var+offset, "nobranch"))
+		return WT_STATUS_NOBRANCH;
+	if (!strcasecmp(var+offset, "unmerged"))
+		return WT_STATUS_UNMERGED;
+	return -1;
+}
+
+static int git_status_config(const char *k, const char *v, void *cb)
+{
+	struct wt_status *s = cb;
+
+	if (!strcmp(k, "status.submodulesummary")) {
+		int is_bool;
+		s->submodule_summary = git_config_bool_or_int(k, v, &is_bool);
+		if (is_bool && s->submodule_summary)
+			s->submodule_summary = -1;
+		return 0;
+	}
+	if (!strcmp(k, "status.color") || !strcmp(k, "color.status")) {
+		s->use_color = git_config_colorbool(k, v, -1);
+		return 0;
+	}
+	if (!prefixcmp(k, "status.color.") || !prefixcmp(k, "color.status.")) {
+		int slot = parse_status_slot(k, 13);
+		if (slot < 0)
+			return 0;
+		if (!v)
+			return config_error_nonbool(k);
+		color_parse(v, k, s->color_palette[slot]);
+		return 0;
+	}
+	if (!strcmp(k, "status.relativepaths")) {
+		s->relative_paths = git_config_bool(k, v);
+		return 0;
+	}
+	if (!strcmp(k, "status.showuntrackedfiles")) {
+		if (!v)
+			return config_error_nonbool(k);
+		else if (!strcmp(v, "no"))
+			s->show_untracked_files = SHOW_NO_UNTRACKED_FILES;
+		else if (!strcmp(v, "normal"))
+			s->show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
+		else if (!strcmp(v, "all"))
+			s->show_untracked_files = SHOW_ALL_UNTRACKED_FILES;
+		else
+			return error("Invalid untracked files mode '%s'", v);
+		return 0;
+	}
+	return git_diff_ui_config(k, v, NULL);
+}
+
+int cmd_status(int argc, const char **argv, const char *prefix)
+{
+	struct wt_status s;
+	unsigned char sha1[20];
+	static struct option builtin_status_options[] = {
+		OPT__VERBOSE(&verbose),
+		OPT_SET_INT('s', "short", &status_format,
+			    "show status concisely", STATUS_FORMAT_SHORT),
+		OPT_SET_INT(0, "porcelain", &status_format,
+			    "show porcelain output format",
+			    STATUS_FORMAT_PORCELAIN),
+		OPT_BOOLEAN('z', "null", &null_termination,
+			    "terminate entries with NUL"),
+		{ OPTION_STRING, 'u', "untracked-files", &untracked_files_arg,
+		  "mode",
+		  "show untracked files, optional modes: all, normal, no. (Default: all)",
+		  PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
+		OPT_END(),
+	};
+
+	if (null_termination && status_format == STATUS_FORMAT_LONG)
+		status_format = STATUS_FORMAT_PORCELAIN;
+
+	wt_status_prepare(&s);
+	git_config(git_status_config, &s);
+	in_merge = file_exists(git_path("MERGE_HEAD"));
+	argc = parse_options(argc, argv, prefix,
+			     builtin_status_options,
+			     builtin_status_usage, 0);
+	handle_untracked_files_arg(&s);
+
+	if (*argv)
+		s.pathspec = get_pathspec(prefix, argv);
+
+	read_cache_preload(s.pathspec);
+	refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, s.pathspec, NULL, NULL);
+	s.is_initial = get_sha1(s.reference, sha1) ? 1 : 0;
+	s.in_merge = in_merge;
+	wt_status_collect(&s);
+
+	if (s.relative_paths)
+		s.prefix = prefix;
+	if (s.use_color == -1)
+		s.use_color = git_use_color_default;
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	switch (status_format) {
+	case STATUS_FORMAT_SHORT:
+		wt_shortstatus_print(&s, null_termination);
+		break;
+	case STATUS_FORMAT_PORCELAIN:
+		wt_porcelain_print(&s, null_termination);
+		break;
+	case STATUS_FORMAT_LONG:
+		s.verbose = verbose;
+		wt_status_print(&s);
+		break;
+	}
+	return 0;
+}
+
+static void print_summary(const char *prefix, const unsigned char *sha1)
+{
+	struct rev_info rev;
+	struct commit *commit;
+	struct strbuf format = STRBUF_INIT;
+	unsigned char junk_sha1[20];
+	const char *head = resolve_ref("HEAD", junk_sha1, 0, NULL);
+	struct pretty_print_context pctx = {0};
+	struct strbuf author_ident = STRBUF_INIT;
+	struct strbuf committer_ident = STRBUF_INIT;
+
+	commit = lookup_commit(sha1);
+	if (!commit)
+		die("couldn't look up newly created commit");
+	if (!commit || parse_commit(commit))
+		die("could not parse newly created commit");
+
+	strbuf_addstr(&format, "format:%h] %s");
+
+	format_commit_message(commit, "%an <%ae>", &author_ident, &pctx);
+	format_commit_message(commit, "%cn <%ce>", &committer_ident, &pctx);
+	if (strbuf_cmp(&author_ident, &committer_ident)) {
+		strbuf_addstr(&format, "\n Author: ");
+		strbuf_addbuf_percentquote(&format, &author_ident);
+	}
+	if (!user_ident_sufficiently_given()) {
+		strbuf_addstr(&format, "\n Committer: ");
+		strbuf_addbuf_percentquote(&format, &committer_ident);
+		if (advice_implicit_identity) {
+			strbuf_addch(&format, '\n');
+			strbuf_addstr(&format, implicit_ident_advice);
+		}
+	}
+	strbuf_release(&author_ident);
+	strbuf_release(&committer_ident);
+
+	init_revisions(&rev, prefix);
+	setup_revisions(0, NULL, &rev, NULL);
+
+	rev.abbrev = 0;
+	rev.diff = 1;
+	rev.diffopt.output_format =
+		DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
+
+	rev.verbose_header = 1;
+	rev.show_root_diff = 1;
+	get_commit_format(format.buf, &rev);
+	rev.always_show_header = 0;
+	rev.diffopt.detect_rename = 1;
+	rev.diffopt.rename_limit = 100;
+	rev.diffopt.break_opt = 0;
+	diff_setup_done(&rev.diffopt);
+
+	printf("[%s%s ",
+		!prefixcmp(head, "refs/heads/") ?
+			head + 11 :
+			!strcmp(head, "HEAD") ?
+				"detached HEAD" :
+				head,
+		initial_commit ? " (root-commit)" : "");
+
+	if (!log_tree_commit(&rev, commit)) {
+		struct pretty_print_context ctx = {0};
+		struct strbuf buf = STRBUF_INIT;
+		ctx.date_mode = DATE_NORMAL;
+		format_commit_message(commit, format.buf + 7, &buf, &ctx);
+		printf("%s\n", buf.buf);
+		strbuf_release(&buf);
+	}
+	strbuf_release(&format);
+}
+
+static int git_commit_config(const char *k, const char *v, void *cb)
+{
+	struct wt_status *s = cb;
+
+	if (!strcmp(k, "commit.template"))
+		return git_config_pathname(&template_file, k, v);
+	if (!strcmp(k, "commit.status")) {
+		include_status = git_config_bool(k, v);
+		return 0;
+	}
+
+	return git_status_config(k, v, s);
+}
+
+int cmd_commit(int argc, const char **argv, const char *prefix)
+{
+	struct strbuf sb = STRBUF_INIT;
+	const char *index_file, *reflog_msg;
+	char *nl, *p;
+	unsigned char commit_sha1[20];
+	struct ref_lock *ref_lock;
+	struct commit_list *parents = NULL, **pptr = &parents;
+	struct stat statbuf;
+	int allow_fast_forward = 1;
+	struct wt_status s;
+
+	wt_status_prepare(&s);
+	git_config(git_commit_config, &s);
+	in_merge = file_exists(git_path("MERGE_HEAD"));
+	s.in_merge = in_merge;
+
+	if (s.use_color == -1)
+		s.use_color = git_use_color_default;
+	argc = parse_and_validate_options(argc, argv, builtin_commit_usage,
+					  prefix, &s);
+	if (dry_run) {
+		if (diff_use_color_default == -1)
+			diff_use_color_default = git_use_color_default;
+		return dry_run_commit(argc, argv, prefix, &s);
+	}
+	index_file = prepare_index(argc, argv, prefix, 0);
+
+	/* Set up everything for writing the commit object.  This includes
+	   running hooks, writing the trees, and interacting with the user.  */
+	if (!prepare_to_commit(index_file, prefix, &s)) {
+		rollback_index_files();
+		return 1;
+	}
+
+	/* Determine parents */
+	if (initial_commit) {
+		reflog_msg = "commit (initial)";
+	} else if (amend) {
+		struct commit_list *c;
+		struct commit *commit;
+
+		reflog_msg = "commit (amend)";
+		commit = lookup_commit(head_sha1);
+		if (!commit || parse_commit(commit))
+			die("could not parse HEAD commit");
+
+		for (c = commit->parents; c; c = c->next)
+			pptr = &commit_list_insert(c->item, pptr)->next;
+	} else if (in_merge) {
+		struct strbuf m = STRBUF_INIT;
+		FILE *fp;
+
+		reflog_msg = "commit (merge)";
+		pptr = &commit_list_insert(lookup_commit(head_sha1), pptr)->next;
+		fp = fopen(git_path("MERGE_HEAD"), "r");
+		if (fp == NULL)
+			die_errno("could not open '%s' for reading",
+				  git_path("MERGE_HEAD"));
+		while (strbuf_getline(&m, fp, '\n') != EOF) {
+			unsigned char sha1[20];
+			if (get_sha1_hex(m.buf, sha1) < 0)
+				die("Corrupt MERGE_HEAD file (%s)", m.buf);
+			pptr = &commit_list_insert(lookup_commit(sha1), pptr)->next;
+		}
+		fclose(fp);
+		strbuf_release(&m);
+		if (!stat(git_path("MERGE_MODE"), &statbuf)) {
+			if (strbuf_read_file(&sb, git_path("MERGE_MODE"), 0) < 0)
+				die_errno("could not read MERGE_MODE");
+			if (!strcmp(sb.buf, "no-ff"))
+				allow_fast_forward = 0;
+		}
+		if (allow_fast_forward)
+			parents = reduce_heads(parents);
+	} else {
+		reflog_msg = "commit";
+		pptr = &commit_list_insert(lookup_commit(head_sha1), pptr)->next;
+	}
+
+	/* Finally, get the commit message */
+	strbuf_reset(&sb);
+	if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
+		int saved_errno = errno;
+		rollback_index_files();
+		die("could not read commit message: %s", strerror(saved_errno));
+	}
+
+	/* Truncate the message just before the diff, if any. */
+	if (verbose) {
+		p = strstr(sb.buf, "\ndiff --git ");
+		if (p != NULL)
+			strbuf_setlen(&sb, p - sb.buf + 1);
+	}
+
+	if (cleanup_mode != CLEANUP_NONE)
+		stripspace(&sb, cleanup_mode == CLEANUP_ALL);
+	if (message_is_empty(&sb)) {
+		rollback_index_files();
+		fprintf(stderr, "Aborting commit due to empty commit message.\n");
+		exit(1);
+	}
+
+	if (commit_tree(sb.buf, active_cache_tree->sha1, parents, commit_sha1,
+			fmt_ident(author_name, author_email, author_date,
+				IDENT_ERROR_ON_NO_NAME))) {
+		rollback_index_files();
+		die("failed to write commit object");
+	}
+
+	ref_lock = lock_any_ref_for_update("HEAD",
+					   initial_commit ? NULL : head_sha1,
+					   0);
+
+	nl = strchr(sb.buf, '\n');
+	if (nl)
+		strbuf_setlen(&sb, nl + 1 - sb.buf);
+	else
+		strbuf_addch(&sb, '\n');
+	strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
+	strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
+
+	if (!ref_lock) {
+		rollback_index_files();
+		die("cannot lock HEAD ref");
+	}
+	if (write_ref_sha1(ref_lock, commit_sha1, sb.buf) < 0) {
+		rollback_index_files();
+		die("cannot update HEAD ref");
+	}
+
+	unlink(git_path("MERGE_HEAD"));
+	unlink(git_path("MERGE_MSG"));
+	unlink(git_path("MERGE_MODE"));
+	unlink(git_path("SQUASH_MSG"));
+
+	if (commit_index_files())
+		die ("Repository has been updated, but unable to write\n"
+		     "new_index file. Check that disk is not full or quota is\n"
+		     "not exceeded, and then \"git reset HEAD\" to recover.");
+
+	rerere(0);
+	run_hook(get_index_file(), "post-commit", NULL);
+	if (!quiet)
+		print_summary(prefix, commit_sha1);
+
+	return 0;
+}
diff --git a/builtin/config.c b/builtin/config.c
new file mode 100644
index 0000000..4bc46b1
--- /dev/null
+++ b/builtin/config.c
@@ -0,0 +1,496 @@
+#include "builtin.h"
+#include "cache.h"
+#include "color.h"
+#include "parse-options.h"
+
+static const char *const builtin_config_usage[] = {
+	"git config [options]",
+	NULL
+};
+
+static char *key;
+static regex_t *key_regexp;
+static regex_t *regexp;
+static int show_keys;
+static int use_key_regexp;
+static int do_all;
+static int do_not_match;
+static int seen;
+static char delim = '=';
+static char key_delim = ' ';
+static char term = '\n';
+
+static int use_global_config, use_system_config;
+static const char *given_config_file;
+static int actions, types;
+static const char *get_color_slot, *get_colorbool_slot;
+static int end_null;
+
+#define ACTION_GET (1<<0)
+#define ACTION_GET_ALL (1<<1)
+#define ACTION_GET_REGEXP (1<<2)
+#define ACTION_REPLACE_ALL (1<<3)
+#define ACTION_ADD (1<<4)
+#define ACTION_UNSET (1<<5)
+#define ACTION_UNSET_ALL (1<<6)
+#define ACTION_RENAME_SECTION (1<<7)
+#define ACTION_REMOVE_SECTION (1<<8)
+#define ACTION_LIST (1<<9)
+#define ACTION_EDIT (1<<10)
+#define ACTION_SET (1<<11)
+#define ACTION_SET_ALL (1<<12)
+#define ACTION_GET_COLOR (1<<13)
+#define ACTION_GET_COLORBOOL (1<<14)
+
+#define TYPE_BOOL (1<<0)
+#define TYPE_INT (1<<1)
+#define TYPE_BOOL_OR_INT (1<<2)
+#define TYPE_PATH (1<<3)
+
+static struct option builtin_config_options[] = {
+	OPT_GROUP("Config file location"),
+	OPT_BOOLEAN(0, "global", &use_global_config, "use global config file"),
+	OPT_BOOLEAN(0, "system", &use_system_config, "use system config file"),
+	OPT_STRING('f', "file", &given_config_file, "FILE", "use given config file"),
+	OPT_GROUP("Action"),
+	OPT_BIT(0, "get", &actions, "get value: name [value-regex]", ACTION_GET),
+	OPT_BIT(0, "get-all", &actions, "get all values: key [value-regex]", ACTION_GET_ALL),
+	OPT_BIT(0, "get-regexp", &actions, "get values for regexp: name-regex [value-regex]", ACTION_GET_REGEXP),
+	OPT_BIT(0, "replace-all", &actions, "replace all matching variables: name value [value_regex]", ACTION_REPLACE_ALL),
+	OPT_BIT(0, "add", &actions, "adds a new variable: name value", ACTION_ADD),
+	OPT_BIT(0, "unset", &actions, "removes a variable: name [value-regex]", ACTION_UNSET),
+	OPT_BIT(0, "unset-all", &actions, "removes all matches: name [value-regex]", ACTION_UNSET_ALL),
+	OPT_BIT(0, "rename-section", &actions, "rename section: old-name new-name", ACTION_RENAME_SECTION),
+	OPT_BIT(0, "remove-section", &actions, "remove a section: name", ACTION_REMOVE_SECTION),
+	OPT_BIT('l', "list", &actions, "list all", ACTION_LIST),
+	OPT_BIT('e', "edit", &actions, "opens an editor", ACTION_EDIT),
+	OPT_STRING(0, "get-color", &get_color_slot, "slot", "find the color configured: [default]"),
+	OPT_STRING(0, "get-colorbool", &get_colorbool_slot, "slot", "find the color setting: [stdout-is-tty]"),
+	OPT_GROUP("Type"),
+	OPT_BIT(0, "bool", &types, "value is \"true\" or \"false\"", TYPE_BOOL),
+	OPT_BIT(0, "int", &types, "value is decimal number", TYPE_INT),
+	OPT_BIT(0, "bool-or-int", &types, "value is --bool or --int", TYPE_BOOL_OR_INT),
+	OPT_BIT(0, "path", &types, "value is a path (file or directory name)", TYPE_PATH),
+	OPT_GROUP("Other"),
+	OPT_BOOLEAN('z', "null", &end_null, "terminate values with NUL byte"),
+	OPT_END(),
+};
+
+static void check_argc(int argc, int min, int max) {
+	if (argc >= min && argc <= max)
+		return;
+	error("wrong number of arguments");
+	usage_with_options(builtin_config_usage, builtin_config_options);
+}
+
+static int show_all_config(const char *key_, const char *value_, void *cb)
+{
+	if (value_)
+		printf("%s%c%s%c", key_, delim, value_, term);
+	else
+		printf("%s%c", key_, term);
+	return 0;
+}
+
+static int show_config(const char *key_, const char *value_, void *cb)
+{
+	char value[256];
+	const char *vptr = value;
+	int must_free_vptr = 0;
+	int dup_error = 0;
+
+	if (!use_key_regexp && strcmp(key_, key))
+		return 0;
+	if (use_key_regexp && regexec(key_regexp, key_, 0, NULL, 0))
+		return 0;
+	if (regexp != NULL &&
+	    (do_not_match ^ !!regexec(regexp, (value_?value_:""), 0, NULL, 0)))
+		return 0;
+
+	if (show_keys) {
+		if (value_)
+			printf("%s%c", key_, key_delim);
+		else
+			printf("%s", key_);
+	}
+	if (seen && !do_all)
+		dup_error = 1;
+	if (types == TYPE_INT)
+		sprintf(value, "%d", git_config_int(key_, value_?value_:""));
+	else if (types == TYPE_BOOL)
+		vptr = git_config_bool(key_, value_) ? "true" : "false";
+	else if (types == TYPE_BOOL_OR_INT) {
+		int is_bool, v;
+		v = git_config_bool_or_int(key_, value_, &is_bool);
+		if (is_bool)
+			vptr = v ? "true" : "false";
+		else
+			sprintf(value, "%d", v);
+	} else if (types == TYPE_PATH) {
+		git_config_pathname(&vptr, key_, value_);
+		must_free_vptr = 1;
+	}
+	else
+		vptr = value_?value_:"";
+	seen++;
+	if (dup_error) {
+		error("More than one value for the key %s: %s",
+				key_, vptr);
+	}
+	else
+		printf("%s%c", vptr, term);
+	if (must_free_vptr)
+		/* If vptr must be freed, it's a pointer to a
+		 * dynamically allocated buffer, it's safe to cast to
+		 * const.
+		*/
+		free((char *)vptr);
+
+	return 0;
+}
+
+static int get_value(const char *key_, const char *regex_)
+{
+	int ret = -1;
+	char *tl;
+	char *global = NULL, *repo_config = NULL;
+	const char *system_wide = NULL, *local;
+
+	local = config_exclusive_filename;
+	if (!local) {
+		const char *home = getenv("HOME");
+		local = repo_config = git_pathdup("config");
+		if (git_config_global() && home)
+			global = xstrdup(mkpath("%s/.gitconfig", home));
+		if (git_config_system())
+			system_wide = git_etc_gitconfig();
+	}
+
+	key = xstrdup(key_);
+	for (tl=key+strlen(key)-1; tl >= key && *tl != '.'; --tl)
+		*tl = tolower(*tl);
+	for (tl=key; *tl && *tl != '.'; ++tl)
+		*tl = tolower(*tl);
+
+	if (use_key_regexp) {
+		key_regexp = (regex_t*)xmalloc(sizeof(regex_t));
+		if (regcomp(key_regexp, key, REG_EXTENDED)) {
+			fprintf(stderr, "Invalid key pattern: %s\n", key_);
+			goto free_strings;
+		}
+	}
+
+	if (regex_) {
+		if (regex_[0] == '!') {
+			do_not_match = 1;
+			regex_++;
+		}
+
+		regexp = (regex_t*)xmalloc(sizeof(regex_t));
+		if (regcomp(regexp, regex_, REG_EXTENDED)) {
+			fprintf(stderr, "Invalid pattern: %s\n", regex_);
+			goto free_strings;
+		}
+	}
+
+	if (do_all && system_wide)
+		git_config_from_file(show_config, system_wide, NULL);
+	if (do_all && global)
+		git_config_from_file(show_config, global, NULL);
+	git_config_from_file(show_config, local, NULL);
+	if (!do_all && !seen && global)
+		git_config_from_file(show_config, global, NULL);
+	if (!do_all && !seen && system_wide)
+		git_config_from_file(show_config, system_wide, NULL);
+
+	free(key);
+	if (regexp) {
+		regfree(regexp);
+		free(regexp);
+	}
+
+	if (do_all)
+		ret = !seen;
+	else
+		ret = (seen == 1) ? 0 : seen > 1 ? 2 : 1;
+
+free_strings:
+	free(repo_config);
+	free(global);
+	return ret;
+}
+
+static char *normalize_value(const char *key, const char *value)
+{
+	char *normalized;
+
+	if (!value)
+		return NULL;
+
+	if (types == 0 || types == TYPE_PATH)
+		/*
+		 * We don't do normalization for TYPE_PATH here: If
+		 * the path is like ~/foobar/, we prefer to store
+		 * "~/foobar/" in the config file, and to expand the ~
+		 * when retrieving the value.
+		 */
+		normalized = xstrdup(value);
+	else {
+		normalized = xmalloc(64);
+		if (types == TYPE_INT) {
+			int v = git_config_int(key, value);
+			sprintf(normalized, "%d", v);
+		}
+		else if (types == TYPE_BOOL)
+			sprintf(normalized, "%s",
+				git_config_bool(key, value) ? "true" : "false");
+		else if (types == TYPE_BOOL_OR_INT) {
+			int is_bool, v;
+			v = git_config_bool_or_int(key, value, &is_bool);
+			if (!is_bool)
+				sprintf(normalized, "%d", v);
+			else
+				sprintf(normalized, "%s", v ? "true" : "false");
+		}
+	}
+
+	return normalized;
+}
+
+static int get_color_found;
+static const char *get_color_slot;
+static const char *get_colorbool_slot;
+static char parsed_color[COLOR_MAXLEN];
+
+static int git_get_color_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, get_color_slot)) {
+		if (!value)
+			config_error_nonbool(var);
+		color_parse(value, var, parsed_color);
+		get_color_found = 1;
+	}
+	return 0;
+}
+
+static void get_color(const char *def_color)
+{
+	get_color_found = 0;
+	parsed_color[0] = '\0';
+	git_config(git_get_color_config, NULL);
+
+	if (!get_color_found && def_color)
+		color_parse(def_color, "command line", parsed_color);
+
+	fputs(parsed_color, stdout);
+}
+
+static int stdout_is_tty;
+static int get_colorbool_found;
+static int get_diff_color_found;
+static int git_get_colorbool_config(const char *var, const char *value,
+		void *cb)
+{
+	if (!strcmp(var, get_colorbool_slot)) {
+		get_colorbool_found =
+			git_config_colorbool(var, value, stdout_is_tty);
+	}
+	if (!strcmp(var, "diff.color")) {
+		get_diff_color_found =
+			git_config_colorbool(var, value, stdout_is_tty);
+	}
+	if (!strcmp(var, "color.ui")) {
+		git_use_color_default = git_config_colorbool(var, value, stdout_is_tty);
+		return 0;
+	}
+	return 0;
+}
+
+static int get_colorbool(int print)
+{
+	get_colorbool_found = -1;
+	get_diff_color_found = -1;
+	git_config(git_get_colorbool_config, NULL);
+
+	if (get_colorbool_found < 0) {
+		if (!strcmp(get_colorbool_slot, "color.diff"))
+			get_colorbool_found = get_diff_color_found;
+		if (get_colorbool_found < 0)
+			get_colorbool_found = git_use_color_default;
+	}
+
+	if (print) {
+		printf("%s\n", get_colorbool_found ? "true" : "false");
+		return 0;
+	} else
+		return get_colorbool_found ? 0 : 1;
+}
+
+int cmd_config(int argc, const char **argv, const char *unused_prefix)
+{
+	int nongit;
+	char *value;
+	const char *prefix = setup_git_directory_gently(&nongit);
+
+	config_exclusive_filename = getenv(CONFIG_ENVIRONMENT);
+
+	argc = parse_options(argc, argv, prefix, builtin_config_options,
+			     builtin_config_usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (use_global_config + use_system_config + !!given_config_file > 1) {
+		error("only one config file at a time.");
+		usage_with_options(builtin_config_usage, builtin_config_options);
+	}
+
+	if (use_global_config) {
+		char *home = getenv("HOME");
+		if (home) {
+			char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
+			config_exclusive_filename = user_config;
+		} else {
+			die("$HOME not set");
+		}
+	}
+	else if (use_system_config)
+		config_exclusive_filename = git_etc_gitconfig();
+	else if (given_config_file) {
+		if (!is_absolute_path(given_config_file) && prefix)
+			config_exclusive_filename = prefix_filename(prefix,
+								    strlen(prefix),
+								    given_config_file);
+		else
+			config_exclusive_filename = given_config_file;
+	}
+
+	if (end_null) {
+		term = '\0';
+		delim = '\n';
+		key_delim = '\n';
+	}
+
+	if (HAS_MULTI_BITS(types)) {
+		error("only one type at a time.");
+		usage_with_options(builtin_config_usage, builtin_config_options);
+	}
+
+	if (get_color_slot)
+	    actions |= ACTION_GET_COLOR;
+	if (get_colorbool_slot)
+	    actions |= ACTION_GET_COLORBOOL;
+
+	if ((get_color_slot || get_colorbool_slot) && types) {
+		error("--get-color and variable type are incoherent");
+		usage_with_options(builtin_config_usage, builtin_config_options);
+	}
+
+	if (HAS_MULTI_BITS(actions)) {
+		error("only one action at a time.");
+		usage_with_options(builtin_config_usage, builtin_config_options);
+	}
+	if (actions == 0)
+		switch (argc) {
+		case 1: actions = ACTION_GET; break;
+		case 2: actions = ACTION_SET; break;
+		case 3: actions = ACTION_SET_ALL; break;
+		default:
+			usage_with_options(builtin_config_usage, builtin_config_options);
+		}
+
+	if (actions == ACTION_LIST) {
+		check_argc(argc, 0, 0);
+		if (git_config(show_all_config, NULL) < 0) {
+			if (config_exclusive_filename)
+				die_errno("unable to read config file '%s'",
+					  config_exclusive_filename);
+			else
+				die("error processing config file(s)");
+		}
+	}
+	else if (actions == ACTION_EDIT) {
+		check_argc(argc, 0, 0);
+		if (!config_exclusive_filename && nongit)
+			die("not in a git directory");
+		git_config(git_default_config, NULL);
+		launch_editor(config_exclusive_filename ?
+			      config_exclusive_filename : git_path("config"),
+			      NULL, NULL);
+	}
+	else if (actions == ACTION_SET) {
+		check_argc(argc, 2, 2);
+		value = normalize_value(argv[0], argv[1]);
+		return git_config_set(argv[0], value);
+	}
+	else if (actions == ACTION_SET_ALL) {
+		check_argc(argc, 2, 3);
+		value = normalize_value(argv[0], argv[1]);
+		return git_config_set_multivar(argv[0], value, argv[2], 0);
+	}
+	else if (actions == ACTION_ADD) {
+		check_argc(argc, 2, 2);
+		value = normalize_value(argv[0], argv[1]);
+		return git_config_set_multivar(argv[0], value, "^$", 0);
+	}
+	else if (actions == ACTION_REPLACE_ALL) {
+		check_argc(argc, 2, 3);
+		value = normalize_value(argv[0], argv[1]);
+		return git_config_set_multivar(argv[0], value, argv[2], 1);
+	}
+	else if (actions == ACTION_GET) {
+		check_argc(argc, 1, 2);
+		return get_value(argv[0], argv[1]);
+	}
+	else if (actions == ACTION_GET_ALL) {
+		do_all = 1;
+		check_argc(argc, 1, 2);
+		return get_value(argv[0], argv[1]);
+	}
+	else if (actions == ACTION_GET_REGEXP) {
+		show_keys = 1;
+		use_key_regexp = 1;
+		do_all = 1;
+		check_argc(argc, 1, 2);
+		return get_value(argv[0], argv[1]);
+	}
+	else if (actions == ACTION_UNSET) {
+		check_argc(argc, 1, 2);
+		if (argc == 2)
+			return git_config_set_multivar(argv[0], NULL, argv[1], 0);
+		else
+			return git_config_set(argv[0], NULL);
+	}
+	else if (actions == ACTION_UNSET_ALL) {
+		check_argc(argc, 1, 2);
+		return git_config_set_multivar(argv[0], NULL, argv[1], 1);
+	}
+	else if (actions == ACTION_RENAME_SECTION) {
+		int ret;
+		check_argc(argc, 2, 2);
+		ret = git_config_rename_section(argv[0], argv[1]);
+		if (ret < 0)
+			return ret;
+		if (ret == 0)
+			die("No such section!");
+	}
+	else if (actions == ACTION_REMOVE_SECTION) {
+		int ret;
+		check_argc(argc, 1, 1);
+		ret = git_config_rename_section(argv[0], NULL);
+		if (ret < 0)
+			return ret;
+		if (ret == 0)
+			die("No such section!");
+	}
+	else if (actions == ACTION_GET_COLOR) {
+		get_color(argv[0]);
+	}
+	else if (actions == ACTION_GET_COLORBOOL) {
+		if (argc == 1)
+			stdout_is_tty = git_config_bool("command line", argv[0]);
+		else if (argc == 0)
+			stdout_is_tty = isatty(1);
+		return get_colorbool(argc != 0);
+	}
+
+	return 0;
+}
diff --git a/builtin/count-objects.c b/builtin/count-objects.c
new file mode 100644
index 0000000..2bdd8eb
--- /dev/null
+++ b/builtin/count-objects.c
@@ -0,0 +1,130 @@
+/*
+ * Builtin "git count-objects".
+ *
+ * Copyright (c) 2006 Junio C Hamano
+ */
+
+#include "cache.h"
+#include "dir.h"
+#include "builtin.h"
+#include "parse-options.h"
+
+static void count_objects(DIR *d, char *path, int len, int verbose,
+			  unsigned long *loose,
+			  off_t *loose_size,
+			  unsigned long *packed_loose,
+			  unsigned long *garbage)
+{
+	struct dirent *ent;
+	while ((ent = readdir(d)) != NULL) {
+		char hex[41];
+		unsigned char sha1[20];
+		const char *cp;
+		int bad = 0;
+
+		if (is_dot_or_dotdot(ent->d_name))
+			continue;
+		for (cp = ent->d_name; *cp; cp++) {
+			int ch = *cp;
+			if (('0' <= ch && ch <= '9') ||
+			    ('a' <= ch && ch <= 'f'))
+				continue;
+			bad = 1;
+			break;
+		}
+		if (cp - ent->d_name != 38)
+			bad = 1;
+		else {
+			struct stat st;
+			memcpy(path + len + 3, ent->d_name, 38);
+			path[len + 2] = '/';
+			path[len + 41] = 0;
+			if (lstat(path, &st) || !S_ISREG(st.st_mode))
+				bad = 1;
+			else
+				(*loose_size) += xsize_t(on_disk_bytes(st));
+		}
+		if (bad) {
+			if (verbose) {
+				error("garbage found: %.*s/%s",
+				      len + 2, path, ent->d_name);
+				(*garbage)++;
+			}
+			continue;
+		}
+		(*loose)++;
+		if (!verbose)
+			continue;
+		memcpy(hex, path+len, 2);
+		memcpy(hex+2, ent->d_name, 38);
+		hex[40] = 0;
+		if (get_sha1_hex(hex, sha1))
+			die("internal error");
+		if (has_sha1_pack(sha1))
+			(*packed_loose)++;
+	}
+}
+
+static char const * const count_objects_usage[] = {
+	"git count-objects [-v]",
+	NULL
+};
+
+int cmd_count_objects(int argc, const char **argv, const char *prefix)
+{
+	int i, verbose = 0;
+	const char *objdir = get_object_directory();
+	int len = strlen(objdir);
+	char *path = xmalloc(len + 50);
+	unsigned long loose = 0, packed = 0, packed_loose = 0, garbage = 0;
+	off_t loose_size = 0;
+	struct option opts[] = {
+		OPT__VERBOSE(&verbose),
+		OPT_END(),
+	};
+
+	argc = parse_options(argc, argv, prefix, opts, count_objects_usage, 0);
+	/* we do not take arguments other than flags for now */
+	if (argc)
+		usage_with_options(count_objects_usage, opts);
+	memcpy(path, objdir, len);
+	if (len && objdir[len-1] != '/')
+		path[len++] = '/';
+	for (i = 0; i < 256; i++) {
+		DIR *d;
+		sprintf(path + len, "%02x", i);
+		d = opendir(path);
+		if (!d)
+			continue;
+		count_objects(d, path, len, verbose,
+			      &loose, &loose_size, &packed_loose, &garbage);
+		closedir(d);
+	}
+	if (verbose) {
+		struct packed_git *p;
+		unsigned long num_pack = 0;
+		off_t size_pack = 0;
+		if (!packed_git)
+			prepare_packed_git();
+		for (p = packed_git; p; p = p->next) {
+			if (!p->pack_local)
+				continue;
+			if (open_pack_index(p))
+				continue;
+			packed += p->num_objects;
+			size_pack += p->pack_size + p->index_size;
+			num_pack++;
+		}
+		printf("count: %lu\n", loose);
+		printf("size: %lu\n", (unsigned long) (loose_size / 1024));
+		printf("in-pack: %lu\n", packed);
+		printf("packs: %lu\n", num_pack);
+		printf("size-pack: %lu\n", (unsigned long) (size_pack / 1024));
+		printf("prune-packable: %lu\n", packed_loose);
+		printf("garbage: %lu\n", garbage);
+	}
+	else
+		printf("%lu objects, %lu kilobytes\n",
+		       loose, (unsigned long) (loose_size / 1024));
+	return 0;
+}
diff --git a/builtin/describe.c b/builtin/describe.c
new file mode 100644
index 0000000..71be2a9
--- /dev/null
+++ b/builtin/describe.c
@@ -0,0 +1,396 @@
+#include "cache.h"
+#include "commit.h"
+#include "tag.h"
+#include "refs.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "parse-options.h"
+#include "diff.h"
+
+#define SEEN		(1u<<0)
+#define MAX_TAGS	(FLAG_BITS - 1)
+
+static const char * const describe_usage[] = {
+	"git describe [options] <committish>*",
+	"git describe [options] --dirty",
+	NULL
+};
+
+static int debug;	/* Display lots of verbose info */
+static int all;	/* Any valid ref can be used */
+static int tags;	/* Allow lightweight tags */
+static int longformat;
+static int abbrev = DEFAULT_ABBREV;
+static int max_candidates = 10;
+static int found_names;
+static const char *pattern;
+static int always;
+static const char *dirty;
+
+/* diff-index command arguments to check if working tree is dirty. */
+static const char *diff_index_args[] = {
+	"diff-index", "--quiet", "HEAD", "--", NULL
+};
+
+
+struct commit_name {
+	struct tag *tag;
+	int prio; /* annotated tag = 2, tag = 1, head = 0 */
+	unsigned char sha1[20];
+	char path[FLEX_ARRAY]; /* more */
+};
+static const char *prio_names[] = {
+	"head", "lightweight", "annotated",
+};
+
+static void add_to_known_names(const char *path,
+			       struct commit *commit,
+			       int prio,
+			       const unsigned char *sha1)
+{
+	struct commit_name *e = commit->util;
+	if (!e || e->prio < prio) {
+		size_t len = strlen(path)+1;
+		free(e);
+		e = xmalloc(sizeof(struct commit_name) + len);
+		e->tag = NULL;
+		e->prio = prio;
+		hashcpy(e->sha1, sha1);
+		memcpy(e->path, path, len);
+		commit->util = e;
+	}
+	found_names = 1;
+}
+
+static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+	int might_be_tag = !prefixcmp(path, "refs/tags/");
+	struct commit *commit;
+	struct object *object;
+	unsigned char peeled[20];
+	int is_tag, prio;
+
+	if (!all && !might_be_tag)
+		return 0;
+
+	if (!peel_ref(path, peeled) && !is_null_sha1(peeled)) {
+		commit = lookup_commit_reference_gently(peeled, 1);
+		if (!commit)
+			return 0;
+		is_tag = !!hashcmp(sha1, commit->object.sha1);
+	} else {
+		commit = lookup_commit_reference_gently(sha1, 1);
+		object = parse_object(sha1);
+		if (!commit || !object)
+			return 0;
+		is_tag = object->type == OBJ_TAG;
+	}
+
+	/* If --all, then any refs are used.
+	 * If --tags, then any tags are used.
+	 * Otherwise only annotated tags are used.
+	 */
+	if (might_be_tag) {
+		if (is_tag)
+			prio = 2;
+		else
+			prio = 1;
+
+		if (pattern && fnmatch(pattern, path + 10, 0))
+			prio = 0;
+	}
+	else
+		prio = 0;
+
+	if (!all) {
+		if (!prio)
+			return 0;
+	}
+	add_to_known_names(all ? path + 5 : path + 10, commit, prio, sha1);
+	return 0;
+}
+
+struct possible_tag {
+	struct commit_name *name;
+	int depth;
+	int found_order;
+	unsigned flag_within;
+};
+
+static int compare_pt(const void *a_, const void *b_)
+{
+	struct possible_tag *a = (struct possible_tag *)a_;
+	struct possible_tag *b = (struct possible_tag *)b_;
+	if (a->depth != b->depth)
+		return a->depth - b->depth;
+	if (a->found_order != b->found_order)
+		return a->found_order - b->found_order;
+	return 0;
+}
+
+static unsigned long finish_depth_computation(
+	struct commit_list **list,
+	struct possible_tag *best)
+{
+	unsigned long seen_commits = 0;
+	while (*list) {
+		struct commit *c = pop_commit(list);
+		struct commit_list *parents = c->parents;
+		seen_commits++;
+		if (c->object.flags & best->flag_within) {
+			struct commit_list *a = *list;
+			while (a) {
+				struct commit *i = a->item;
+				if (!(i->object.flags & best->flag_within))
+					break;
+				a = a->next;
+			}
+			if (!a)
+				break;
+		} else
+			best->depth++;
+		while (parents) {
+			struct commit *p = parents->item;
+			parse_commit(p);
+			if (!(p->object.flags & SEEN))
+				insert_by_date(p, list);
+			p->object.flags |= c->object.flags;
+			parents = parents->next;
+		}
+	}
+	return seen_commits;
+}
+
+static void display_name(struct commit_name *n)
+{
+	if (n->prio == 2 && !n->tag) {
+		n->tag = lookup_tag(n->sha1);
+		if (!n->tag || parse_tag(n->tag) || !n->tag->tag)
+			die("annotated tag %s not available", n->path);
+		if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
+			warning("tag '%s' is really '%s' here", n->tag->tag, n->path);
+	}
+
+	if (n->tag)
+		printf("%s", n->tag->tag);
+	else
+		printf("%s", n->path);
+}
+
+static void show_suffix(int depth, const unsigned char *sha1)
+{
+	printf("-%d-g%s", depth, find_unique_abbrev(sha1, abbrev));
+}
+
+static void describe(const char *arg, int last_one)
+{
+	unsigned char sha1[20];
+	struct commit *cmit, *gave_up_on = NULL;
+	struct commit_list *list;
+	struct commit_name *n;
+	struct possible_tag all_matches[MAX_TAGS];
+	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
+	unsigned long seen_commits = 0;
+	unsigned int unannotated_cnt = 0;
+
+	if (get_sha1(arg, sha1))
+		die("Not a valid object name %s", arg);
+	cmit = lookup_commit_reference(sha1);
+	if (!cmit)
+		die("%s is not a valid '%s' object", arg, commit_type);
+
+	n = cmit->util;
+	if (n && (tags || all || n->prio == 2)) {
+		/*
+		 * Exact match to an existing ref.
+		 */
+		display_name(n);
+		if (longformat)
+			show_suffix(0, n->tag ? n->tag->tagged->sha1 : sha1);
+		if (dirty)
+			printf("%s", dirty);
+		printf("\n");
+		return;
+	}
+
+	if (!max_candidates)
+		die("no tag exactly matches '%s'", sha1_to_hex(cmit->object.sha1));
+	if (debug)
+		fprintf(stderr, "searching to describe %s\n", arg);
+
+	list = NULL;
+	cmit->object.flags = SEEN;
+	commit_list_insert(cmit, &list);
+	while (list) {
+		struct commit *c = pop_commit(&list);
+		struct commit_list *parents = c->parents;
+		seen_commits++;
+		n = c->util;
+		if (n) {
+			if (!tags && !all && n->prio < 2) {
+				unannotated_cnt++;
+			} else if (match_cnt < max_candidates) {
+				struct possible_tag *t = &all_matches[match_cnt++];
+				t->name = n;
+				t->depth = seen_commits - 1;
+				t->flag_within = 1u << match_cnt;
+				t->found_order = match_cnt;
+				c->object.flags |= t->flag_within;
+				if (n->prio == 2)
+					annotated_cnt++;
+			}
+			else {
+				gave_up_on = c;
+				break;
+			}
+		}
+		for (cur_match = 0; cur_match < match_cnt; cur_match++) {
+			struct possible_tag *t = &all_matches[cur_match];
+			if (!(c->object.flags & t->flag_within))
+				t->depth++;
+		}
+		if (annotated_cnt && !list) {
+			if (debug)
+				fprintf(stderr, "finished search at %s\n",
+					sha1_to_hex(c->object.sha1));
+			break;
+		}
+		while (parents) {
+			struct commit *p = parents->item;
+			parse_commit(p);
+			if (!(p->object.flags & SEEN))
+				insert_by_date(p, &list);
+			p->object.flags |= c->object.flags;
+			parents = parents->next;
+		}
+	}
+
+	if (!match_cnt) {
+		const unsigned char *sha1 = cmit->object.sha1;
+		if (always) {
+			printf("%s", find_unique_abbrev(sha1, abbrev));
+			if (dirty)
+				printf("%s", dirty);
+			printf("\n");
+			return;
+		}
+		if (unannotated_cnt)
+			die("No annotated tags can describe '%s'.\n"
+			    "However, there were unannotated tags: try --tags.",
+			    sha1_to_hex(sha1));
+		else
+			die("No tags can describe '%s'.\n"
+			    "Try --always, or create some tags.",
+			    sha1_to_hex(sha1));
+	}
+
+	qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
+
+	if (gave_up_on) {
+		insert_by_date(gave_up_on, &list);
+		seen_commits--;
+	}
+	seen_commits += finish_depth_computation(&list, &all_matches[0]);
+	free_commit_list(list);
+
+	if (debug) {
+		for (cur_match = 0; cur_match < match_cnt; cur_match++) {
+			struct possible_tag *t = &all_matches[cur_match];
+			fprintf(stderr, " %-11s %8d %s\n",
+				prio_names[t->name->prio],
+				t->depth, t->name->path);
+		}
+		fprintf(stderr, "traversed %lu commits\n", seen_commits);
+		if (gave_up_on) {
+			fprintf(stderr,
+				"more than %i tags found; listed %i most recent\n"
+				"gave up search at %s\n",
+				max_candidates, max_candidates,
+				sha1_to_hex(gave_up_on->object.sha1));
+		}
+	}
+
+	display_name(all_matches[0].name);
+	if (abbrev)
+		show_suffix(all_matches[0].depth, cmit->object.sha1);
+	if (dirty)
+		printf("%s", dirty);
+	printf("\n");
+
+	if (!last_one)
+		clear_commit_marks(cmit, -1);
+}
+
+int cmd_describe(int argc, const char **argv, const char *prefix)
+{
+	int contains = 0;
+	struct option options[] = {
+		OPT_BOOLEAN(0, "contains",   &contains, "find the tag that comes after the commit"),
+		OPT_BOOLEAN(0, "debug",      &debug, "debug search strategy on stderr"),
+		OPT_BOOLEAN(0, "all",        &all, "use any ref in .git/refs"),
+		OPT_BOOLEAN(0, "tags",       &tags, "use any tag in .git/refs/tags"),
+		OPT_BOOLEAN(0, "long",       &longformat, "always use long format"),
+		OPT__ABBREV(&abbrev),
+		OPT_SET_INT(0, "exact-match", &max_candidates,
+			    "only output exact matches", 0),
+		OPT_INTEGER(0, "candidates", &max_candidates,
+			    "consider <n> most recent tags (default: 10)"),
+		OPT_STRING(0, "match",       &pattern, "pattern",
+			   "only consider tags matching <pattern>"),
+		OPT_BOOLEAN(0, "always",     &always,
+			   "show abbreviated commit object as fallback"),
+		{OPTION_STRING, 0, "dirty",  &dirty, "mark",
+			   "append <mark> on dirty working tree (default: \"-dirty\")",
+		 PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
+		OPT_END(),
+	};
+
+	argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
+	if (max_candidates < 0)
+		max_candidates = 0;
+	else if (max_candidates > MAX_TAGS)
+		max_candidates = MAX_TAGS;
+
+	save_commit_buffer = 0;
+
+	if (longformat && abbrev == 0)
+		die("--long is incompatible with --abbrev=0");
+
+	if (contains) {
+		const char **args = xmalloc((7 + argc) * sizeof(char *));
+		int i = 0;
+		args[i++] = "name-rev";
+		args[i++] = "--name-only";
+		args[i++] = "--no-undefined";
+		if (always)
+			args[i++] = "--always";
+		if (!all) {
+			args[i++] = "--tags";
+			if (pattern) {
+				char *s = xmalloc(strlen("--refs=refs/tags/") + strlen(pattern) + 1);
+				sprintf(s, "--refs=refs/tags/%s", pattern);
+				args[i++] = s;
+			}
+		}
+		memcpy(args + i, argv, argc * sizeof(char *));
+		args[i + argc] = NULL;
+		return cmd_name_rev(i + argc, args, prefix);
+	}
+
+	for_each_ref(get_name, NULL);
+	if (!found_names && !always)
+		die("No names found, cannot describe anything.");
+
+	if (argc == 0) {
+		if (dirty && !cmd_diff_index(ARRAY_SIZE(diff_index_args) - 1, diff_index_args, prefix))
+			dirty = NULL;
+		describe("HEAD", 1);
+	} else if (dirty) {
+		die("--dirty is incompatible with committishes");
+	} else {
+		while (argc-- > 0) {
+			describe(*argv++, argc == 0);
+		}
+	}
+	return 0;
+}
diff --git a/builtin/diff-files.c b/builtin/diff-files.c
new file mode 100644
index 0000000..5b64011
--- /dev/null
+++ b/builtin/diff-files.c
@@ -0,0 +1,68 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "diff.h"
+#include "commit.h"
+#include "revision.h"
+#include "builtin.h"
+
+static const char diff_files_usage[] =
+"git diff-files [-q] [-0/-1/2/3 |-c|--cc] [<common diff options>] [<path>...]"
+COMMON_DIFF_OPTIONS_HELP;
+
+int cmd_diff_files(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info rev;
+	int result;
+	unsigned options = 0;
+
+	init_revisions(&rev, prefix);
+	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
+	rev.abbrev = 0;
+
+	argc = setup_revisions(argc, argv, &rev, NULL);
+	while (1 < argc && argv[1][0] == '-') {
+		if (!strcmp(argv[1], "--base"))
+			rev.max_count = 1;
+		else if (!strcmp(argv[1], "--ours"))
+			rev.max_count = 2;
+		else if (!strcmp(argv[1], "--theirs"))
+			rev.max_count = 3;
+		else if (!strcmp(argv[1], "-q"))
+			options |= DIFF_SILENT_ON_REMOVED;
+		else
+			usage(diff_files_usage);
+		argv++; argc--;
+	}
+	if (!rev.diffopt.output_format)
+		rev.diffopt.output_format = DIFF_FORMAT_RAW;
+
+	/*
+	 * Make sure there are NO revision (i.e. pending object) parameter,
+	 * rev.max_count is reasonable (0 <= n <= 3), and
+	 * there is no other revision filtering parameters.
+	 */
+	if (rev.pending.nr ||
+	    rev.min_age != -1 || rev.max_age != -1 ||
+	    3 < rev.max_count)
+		usage(diff_files_usage);
+
+	/*
+	 * "diff-files --base -p" should not combine merges because it
+	 * was not asked to.  "diff-files -c -p" should not densify
+	 * (the user should ask with "diff-files --cc" explicitly).
+	 */
+	if (rev.max_count == -1 && !rev.combine_merges &&
+	    (rev.diffopt.output_format & DIFF_FORMAT_PATCH))
+		rev.combine_merges = rev.dense_combined_merges = 1;
+
+	if (read_cache_preload(rev.diffopt.paths) < 0) {
+		perror("read_cache_preload");
+		return -1;
+	}
+	result = run_diff_files(&rev, options);
+	return diff_result_code(&rev.diffopt, result);
+}
diff --git a/builtin/diff-index.c b/builtin/diff-index.c
new file mode 100644
index 0000000..0483749
--- /dev/null
+++ b/builtin/diff-index.c
@@ -0,0 +1,50 @@
+#include "cache.h"
+#include "diff.h"
+#include "commit.h"
+#include "revision.h"
+#include "builtin.h"
+
+static const char diff_cache_usage[] =
+"git diff-index [-m] [--cached] "
+"[<common diff options>] <tree-ish> [<path>...]"
+COMMON_DIFF_OPTIONS_HELP;
+
+int cmd_diff_index(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info rev;
+	int cached = 0;
+	int i;
+	int result;
+
+	init_revisions(&rev, prefix);
+	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
+	rev.abbrev = 0;
+
+	argc = setup_revisions(argc, argv, &rev, NULL);
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (!strcmp(arg, "--cached"))
+			cached = 1;
+		else
+			usage(diff_cache_usage);
+	}
+	if (!rev.diffopt.output_format)
+		rev.diffopt.output_format = DIFF_FORMAT_RAW;
+
+	/*
+	 * Make sure there is one revision (i.e. pending object),
+	 * and there is no revision filtering parameters.
+	 */
+	if (rev.pending.nr != 1 ||
+	    rev.max_count != -1 || rev.min_age != -1 || rev.max_age != -1)
+		usage(diff_cache_usage);
+	if (!cached)
+		setup_work_tree();
+	if (read_cache() < 0) {
+		perror("read_cache");
+		return -1;
+	}
+	result = run_diff_index(&rev, cached);
+	return diff_result_code(&rev.diffopt, result);
+}
diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
new file mode 100644
index 0000000..2380c21
--- /dev/null
+++ b/builtin/diff-tree.c
@@ -0,0 +1,170 @@
+#include "cache.h"
+#include "diff.h"
+#include "commit.h"
+#include "log-tree.h"
+#include "builtin.h"
+
+static struct rev_info log_tree_opt;
+
+static int diff_tree_commit_sha1(const unsigned char *sha1)
+{
+	struct commit *commit = lookup_commit_reference(sha1);
+	if (!commit)
+		return -1;
+	return log_tree_commit(&log_tree_opt, commit);
+}
+
+/* Diff one or more commits. */
+static int stdin_diff_commit(struct commit *commit, char *line, int len)
+{
+	unsigned char sha1[20];
+	if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
+		/* Graft the fake parents locally to the commit */
+		int pos = 41;
+		struct commit_list **pptr, *parents;
+
+		/* Free the real parent list */
+		for (parents = commit->parents; parents; ) {
+			struct commit_list *tmp = parents->next;
+			free(parents);
+			parents = tmp;
+		}
+		commit->parents = NULL;
+		pptr = &(commit->parents);
+		while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
+			struct commit *parent = lookup_commit(sha1);
+			if (parent) {
+				pptr = &commit_list_insert(parent, pptr)->next;
+			}
+			pos += 41;
+		}
+	}
+	return log_tree_commit(&log_tree_opt, commit);
+}
+
+/* Diff two trees. */
+static int stdin_diff_trees(struct tree *tree1, char *line, int len)
+{
+	unsigned char sha1[20];
+	struct tree *tree2;
+	if (len != 82 || !isspace(line[40]) || get_sha1_hex(line + 41, sha1))
+		return error("Need exactly two trees, separated by a space");
+	tree2 = lookup_tree(sha1);
+	if (!tree2 || parse_tree(tree2))
+		return -1;
+	printf("%s %s\n", sha1_to_hex(tree1->object.sha1),
+			  sha1_to_hex(tree2->object.sha1));
+	diff_tree_sha1(tree1->object.sha1, tree2->object.sha1,
+		       "", &log_tree_opt.diffopt);
+	log_tree_diff_flush(&log_tree_opt);
+	return 0;
+}
+
+static int diff_tree_stdin(char *line)
+{
+	int len = strlen(line);
+	unsigned char sha1[20];
+	struct object *obj;
+
+	if (!len || line[len-1] != '\n')
+		return -1;
+	line[len-1] = 0;
+	if (get_sha1_hex(line, sha1))
+		return -1;
+	obj = lookup_unknown_object(sha1);
+	if (!obj || !obj->parsed)
+		obj = parse_object(sha1);
+	if (!obj)
+		return -1;
+	if (obj->type == OBJ_COMMIT)
+		return stdin_diff_commit((struct commit *)obj, line, len);
+	if (obj->type == OBJ_TREE)
+		return stdin_diff_trees((struct tree *)obj, line, len);
+	error("Object %s is a %s, not a commit or tree",
+	      sha1_to_hex(sha1), typename(obj->type));
+	return -1;
+}
+
+static const char diff_tree_usage[] =
+"git diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
+"[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
+"  -r            diff recursively\n"
+"  --root        include the initial commit as diff against /dev/null\n"
+COMMON_DIFF_OPTIONS_HELP;
+
+int cmd_diff_tree(int argc, const char **argv, const char *prefix)
+{
+	int nr_sha1;
+	char line[1000];
+	struct object *tree1, *tree2;
+	static struct rev_info *opt = &log_tree_opt;
+	int read_stdin = 0;
+
+	init_revisions(opt, prefix);
+	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
+	opt->abbrev = 0;
+	opt->diff = 1;
+	opt->disable_stdin = 1;
+	argc = setup_revisions(argc, argv, opt, NULL);
+
+	while (--argc > 0) {
+		const char *arg = *++argv;
+
+		if (!strcmp(arg, "--stdin")) {
+			read_stdin = 1;
+			continue;
+		}
+		usage(diff_tree_usage);
+	}
+
+	if (!opt->diffopt.output_format)
+		opt->diffopt.output_format = DIFF_FORMAT_RAW;
+
+	/*
+	 * NOTE! We expect "a ^b" to be equal to "a..b", so we
+	 * reverse the order of the objects if the second one
+	 * is marked UNINTERESTING.
+	 */
+	nr_sha1 = opt->pending.nr;
+	switch (nr_sha1) {
+	case 0:
+		if (!read_stdin)
+			usage(diff_tree_usage);
+		break;
+	case 1:
+		tree1 = opt->pending.objects[0].item;
+		diff_tree_commit_sha1(tree1->sha1);
+		break;
+	case 2:
+		tree1 = opt->pending.objects[0].item;
+		tree2 = opt->pending.objects[1].item;
+		if (tree2->flags & UNINTERESTING) {
+			struct object *tmp = tree2;
+			tree2 = tree1;
+			tree1 = tmp;
+		}
+		diff_tree_sha1(tree1->sha1,
+			       tree2->sha1,
+			       "", &opt->diffopt);
+		log_tree_diff_flush(opt);
+		break;
+	}
+
+	if (read_stdin) {
+		if (opt->diffopt.detect_rename)
+			opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
+					       DIFF_SETUP_USE_CACHE);
+		while (fgets(line, sizeof(line), stdin)) {
+			unsigned char sha1[20];
+
+			if (get_sha1_hex(line, sha1)) {
+				fputs(line, stdout);
+				fflush(stdout);
+			}
+			else
+				diff_tree_stdin(line);
+		}
+	}
+
+	return diff_result_code(&opt->diffopt, 0);
+}
diff --git a/builtin/diff.c b/builtin/diff.c
new file mode 100644
index 0000000..ffcdd05
--- /dev/null
+++ b/builtin/diff.c
@@ -0,0 +1,425 @@
+/*
+ * Builtin "git diff"
+ *
+ * Copyright (c) 2006 Junio C Hamano
+ */
+#include "cache.h"
+#include "color.h"
+#include "commit.h"
+#include "blob.h"
+#include "tag.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "revision.h"
+#include "log-tree.h"
+#include "builtin.h"
+
+struct blobinfo {
+	unsigned char sha1[20];
+	const char *name;
+	unsigned mode;
+};
+
+static const char builtin_diff_usage[] =
+"git diff <options> <rev>{0,2} -- <path>*";
+
+static void stuff_change(struct diff_options *opt,
+			 unsigned old_mode, unsigned new_mode,
+			 const unsigned char *old_sha1,
+			 const unsigned char *new_sha1,
+			 const char *old_name,
+			 const char *new_name)
+{
+	struct diff_filespec *one, *two;
+
+	if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
+	    !hashcmp(old_sha1, new_sha1) && (old_mode == new_mode))
+		return;
+
+	if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
+		unsigned tmp;
+		const unsigned char *tmp_u;
+		const char *tmp_c;
+		tmp = old_mode; old_mode = new_mode; new_mode = tmp;
+		tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
+		tmp_c = old_name; old_name = new_name; new_name = tmp_c;
+	}
+
+	if (opt->prefix &&
+	    (strncmp(old_name, opt->prefix, opt->prefix_length) ||
+	     strncmp(new_name, opt->prefix, opt->prefix_length)))
+		return;
+
+	one = alloc_filespec(old_name);
+	two = alloc_filespec(new_name);
+	fill_filespec(one, old_sha1, old_mode);
+	fill_filespec(two, new_sha1, new_mode);
+
+	diff_queue(&diff_queued_diff, one, two);
+}
+
+static int builtin_diff_b_f(struct rev_info *revs,
+			    int argc, const char **argv,
+			    struct blobinfo *blob,
+			    const char *path)
+{
+	/* Blob vs file in the working tree*/
+	struct stat st;
+
+	if (argc > 1)
+		usage(builtin_diff_usage);
+
+	if (lstat(path, &st))
+		die_errno("failed to stat '%s'", path);
+	if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
+		die("'%s': not a regular file or symlink", path);
+
+	diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
+
+	if (blob[0].mode == S_IFINVALID)
+		blob[0].mode = canon_mode(st.st_mode);
+
+	stuff_change(&revs->diffopt,
+		     blob[0].mode, canon_mode(st.st_mode),
+		     blob[0].sha1, null_sha1,
+		     path, path);
+	diffcore_std(&revs->diffopt);
+	diff_flush(&revs->diffopt);
+	return 0;
+}
+
+static int builtin_diff_blobs(struct rev_info *revs,
+			      int argc, const char **argv,
+			      struct blobinfo *blob)
+{
+	unsigned mode = canon_mode(S_IFREG | 0644);
+
+	if (argc > 1)
+		usage(builtin_diff_usage);
+
+	if (blob[0].mode == S_IFINVALID)
+		blob[0].mode = mode;
+
+	if (blob[1].mode == S_IFINVALID)
+		blob[1].mode = mode;
+
+	stuff_change(&revs->diffopt,
+		     blob[0].mode, blob[1].mode,
+		     blob[0].sha1, blob[1].sha1,
+		     blob[0].name, blob[1].name);
+	diffcore_std(&revs->diffopt);
+	diff_flush(&revs->diffopt);
+	return 0;
+}
+
+static int builtin_diff_index(struct rev_info *revs,
+			      int argc, const char **argv)
+{
+	int cached = 0;
+	while (1 < argc) {
+		const char *arg = argv[1];
+		if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
+			cached = 1;
+		else
+			usage(builtin_diff_usage);
+		argv++; argc--;
+	}
+	if (!cached)
+		setup_work_tree();
+	/*
+	 * Make sure there is one revision (i.e. pending object),
+	 * and there is no revision filtering parameters.
+	 */
+	if (revs->pending.nr != 1 ||
+	    revs->max_count != -1 || revs->min_age != -1 ||
+	    revs->max_age != -1)
+		usage(builtin_diff_usage);
+	if (read_cache_preload(revs->diffopt.paths) < 0) {
+		perror("read_cache_preload");
+		return -1;
+	}
+	return run_diff_index(revs, cached);
+}
+
+static int builtin_diff_tree(struct rev_info *revs,
+			     int argc, const char **argv,
+			     struct object_array_entry *ent)
+{
+	const unsigned char *(sha1[2]);
+	int swap = 0;
+
+	if (argc > 1)
+		usage(builtin_diff_usage);
+
+	/* We saw two trees, ent[0] and ent[1].
+	 * if ent[1] is uninteresting, they are swapped
+	 */
+	if (ent[1].item->flags & UNINTERESTING)
+		swap = 1;
+	sha1[swap] = ent[0].item->sha1;
+	sha1[1-swap] = ent[1].item->sha1;
+	diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
+	log_tree_diff_flush(revs);
+	return 0;
+}
+
+static int builtin_diff_combined(struct rev_info *revs,
+				 int argc, const char **argv,
+				 struct object_array_entry *ent,
+				 int ents)
+{
+	const unsigned char (*parent)[20];
+	int i;
+
+	if (argc > 1)
+		usage(builtin_diff_usage);
+
+	if (!revs->dense_combined_merges && !revs->combine_merges)
+		revs->dense_combined_merges = revs->combine_merges = 1;
+	parent = xmalloc(ents * sizeof(*parent));
+	for (i = 0; i < ents; i++)
+		hashcpy((unsigned char *)(parent + i), ent[i].item->sha1);
+	diff_tree_combined(parent[0], parent + 1, ents - 1,
+			   revs->dense_combined_merges, revs);
+	return 0;
+}
+
+static void refresh_index_quietly(void)
+{
+	struct lock_file *lock_file;
+	int fd;
+
+	lock_file = xcalloc(1, sizeof(struct lock_file));
+	fd = hold_locked_index(lock_file, 0);
+	if (fd < 0)
+		return;
+	discard_cache();
+	read_cache();
+	refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
+
+	if (active_cache_changed &&
+	    !write_cache(fd, active_cache, active_nr))
+		commit_locked_index(lock_file);
+
+	rollback_lock_file(lock_file);
+}
+
+static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
+{
+	int result;
+	unsigned int options = 0;
+
+	while (1 < argc && argv[1][0] == '-') {
+		if (!strcmp(argv[1], "--base"))
+			revs->max_count = 1;
+		else if (!strcmp(argv[1], "--ours"))
+			revs->max_count = 2;
+		else if (!strcmp(argv[1], "--theirs"))
+			revs->max_count = 3;
+		else if (!strcmp(argv[1], "-q"))
+			options |= DIFF_SILENT_ON_REMOVED;
+		else if (!strcmp(argv[1], "-h"))
+			usage(builtin_diff_usage);
+		else
+			return error("invalid option: %s", argv[1]);
+		argv++; argc--;
+	}
+
+	/*
+	 * "diff --base" should not combine merges because it was not
+	 * asked to.  "diff -c" should not densify (if the user wants
+	 * dense one, --cc can be explicitly asked for, or just rely
+	 * on the default).
+	 */
+	if (revs->max_count == -1 && !revs->combine_merges &&
+	    (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
+		revs->combine_merges = revs->dense_combined_merges = 1;
+
+	setup_work_tree();
+	if (read_cache_preload(revs->diffopt.paths) < 0) {
+		perror("read_cache_preload");
+		return -1;
+	}
+	result = run_diff_files(revs, options);
+	return diff_result_code(&revs->diffopt, result);
+}
+
+int cmd_diff(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	struct rev_info rev;
+	struct object_array_entry ent[100];
+	int ents = 0, blobs = 0, paths = 0;
+	const char *path = NULL;
+	struct blobinfo blob[2];
+	int nongit;
+	int result = 0;
+
+	/*
+	 * We could get N tree-ish in the rev.pending_objects list.
+	 * Also there could be M blobs there, and P pathspecs.
+	 *
+	 * N=0, M=0:
+	 *	cache vs files (diff-files)
+	 * N=0, M=2:
+	 *      compare two random blobs.  P must be zero.
+	 * N=0, M=1, P=1:
+	 *	compare a blob with a working tree file.
+	 *
+	 * N=1, M=0:
+	 *      tree vs cache (diff-index --cached)
+	 *
+	 * N=2, M=0:
+	 *      tree vs tree (diff-tree)
+	 *
+	 * N=0, M=0, P=2:
+	 *      compare two filesystem entities (aka --no-index).
+	 *
+	 * Other cases are errors.
+	 */
+
+	prefix = setup_git_directory_gently(&nongit);
+	git_config(git_diff_ui_config, NULL);
+
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	init_revisions(&rev, prefix);
+
+	/* If this is a no-index diff, just run it and exit there. */
+	diff_no_index(&rev, argc, argv, nongit, prefix);
+
+	/* Otherwise, we are doing the usual "git" diff */
+	rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
+
+	/* Default to let external and textconv be used */
+	DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
+	DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
+
+	if (nongit)
+		die("Not a git repository");
+	argc = setup_revisions(argc, argv, &rev, NULL);
+	if (!rev.diffopt.output_format) {
+		rev.diffopt.output_format = DIFF_FORMAT_PATCH;
+		if (diff_setup_done(&rev.diffopt) < 0)
+			die("diff_setup_done failed");
+	}
+
+	DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
+
+	/*
+	 * If the user asked for our exit code then don't start a
+	 * pager or we would end up reporting its exit code instead.
+	 */
+	if (!DIFF_OPT_TST(&rev.diffopt, EXIT_WITH_STATUS) &&
+	    check_pager_config("diff") != 0)
+		setup_pager();
+
+	/*
+	 * Do we have --cached and not have a pending object, then
+	 * default to HEAD by hand.  Eek.
+	 */
+	if (!rev.pending.nr) {
+		int i;
+		for (i = 1; i < argc; i++) {
+			const char *arg = argv[i];
+			if (!strcmp(arg, "--"))
+				break;
+			else if (!strcmp(arg, "--cached") ||
+				 !strcmp(arg, "--staged")) {
+				add_head_to_pending(&rev);
+				if (!rev.pending.nr)
+					die("No HEAD commit to compare with (yet)");
+				break;
+			}
+		}
+	}
+
+	for (i = 0; i < rev.pending.nr; i++) {
+		struct object_array_entry *list = rev.pending.objects+i;
+		struct object *obj = list->item;
+		const char *name = list->name;
+		int flags = (obj->flags & UNINTERESTING);
+		if (!obj->parsed)
+			obj = parse_object(obj->sha1);
+		obj = deref_tag(obj, NULL, 0);
+		if (!obj)
+			die("invalid object '%s' given.", name);
+		if (obj->type == OBJ_COMMIT)
+			obj = &((struct commit *)obj)->tree->object;
+		if (obj->type == OBJ_TREE) {
+			if (ARRAY_SIZE(ent) <= ents)
+				die("more than %d trees given: '%s'",
+				    (int) ARRAY_SIZE(ent), name);
+			obj->flags |= flags;
+			ent[ents].item = obj;
+			ent[ents].name = name;
+			ents++;
+			continue;
+		}
+		if (obj->type == OBJ_BLOB) {
+			if (2 <= blobs)
+				die("more than two blobs given: '%s'", name);
+			hashcpy(blob[blobs].sha1, obj->sha1);
+			blob[blobs].name = name;
+			blob[blobs].mode = list->mode;
+			blobs++;
+			continue;
+
+		}
+		die("unhandled object '%s' given.", name);
+	}
+	if (rev.prune_data) {
+		const char **pathspec = rev.prune_data;
+		while (*pathspec) {
+			if (!path)
+				path = *pathspec;
+			paths++;
+			pathspec++;
+		}
+	}
+
+	/*
+	 * Now, do the arguments look reasonable?
+	 */
+	if (!ents) {
+		switch (blobs) {
+		case 0:
+			result = builtin_diff_files(&rev, argc, argv);
+			break;
+		case 1:
+			if (paths != 1)
+				usage(builtin_diff_usage);
+			result = builtin_diff_b_f(&rev, argc, argv, blob, path);
+			break;
+		case 2:
+			if (paths)
+				usage(builtin_diff_usage);
+			result = builtin_diff_blobs(&rev, argc, argv, blob);
+			break;
+		default:
+			usage(builtin_diff_usage);
+		}
+	}
+	else if (blobs)
+		usage(builtin_diff_usage);
+	else if (ents == 1)
+		result = builtin_diff_index(&rev, argc, argv);
+	else if (ents == 2)
+		result = builtin_diff_tree(&rev, argc, argv, ent);
+	else if ((ents == 3) && (ent[0].item->flags & UNINTERESTING)) {
+		/* diff A...B where there is one sane merge base between
+		 * A and B.  We have ent[0] == merge-base, ent[1] == A,
+		 * and ent[2] == B.  Show diff between the base and B.
+		 */
+		ent[1] = ent[2];
+		result = builtin_diff_tree(&rev, argc, argv, ent);
+	}
+	else
+		result = builtin_diff_combined(&rev, argc, argv,
+					     ent, ents);
+	result = diff_result_code(&rev.diffopt, result);
+	if (1 < rev.diffopt.skip_stat_unmatch)
+		refresh_index_quietly();
+	return result;
+}
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
new file mode 100644
index 0000000..b0a4029
--- /dev/null
+++ b/builtin/fast-export.c
@@ -0,0 +1,633 @@
+/*
+ * "git fast-export" builtin command
+ *
+ * Copyright (C) 2007 Johannes E. Schindelin
+ */
+#include "builtin.h"
+#include "cache.h"
+#include "commit.h"
+#include "object.h"
+#include "tag.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "log-tree.h"
+#include "revision.h"
+#include "decorate.h"
+#include "string-list.h"
+#include "utf8.h"
+#include "parse-options.h"
+
+static const char *fast_export_usage[] = {
+	"git fast-export [rev-list-opts]",
+	NULL
+};
+
+static int progress;
+static enum { ABORT, VERBATIM, WARN, STRIP } signed_tag_mode = ABORT;
+static enum { ERROR, DROP, REWRITE } tag_of_filtered_mode = ABORT;
+static int fake_missing_tagger;
+static int no_data;
+
+static int parse_opt_signed_tag_mode(const struct option *opt,
+				     const char *arg, int unset)
+{
+	if (unset || !strcmp(arg, "abort"))
+		signed_tag_mode = ABORT;
+	else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
+		signed_tag_mode = VERBATIM;
+	else if (!strcmp(arg, "warn"))
+		signed_tag_mode = WARN;
+	else if (!strcmp(arg, "strip"))
+		signed_tag_mode = STRIP;
+	else
+		return error("Unknown signed-tag mode: %s", arg);
+	return 0;
+}
+
+static int parse_opt_tag_of_filtered_mode(const struct option *opt,
+					  const char *arg, int unset)
+{
+	if (unset || !strcmp(arg, "abort"))
+		tag_of_filtered_mode = ABORT;
+	else if (!strcmp(arg, "drop"))
+		tag_of_filtered_mode = DROP;
+	else if (!strcmp(arg, "rewrite"))
+		tag_of_filtered_mode = REWRITE;
+	else
+		return error("Unknown tag-of-filtered mode: %s", arg);
+	return 0;
+}
+
+static struct decoration idnums;
+static uint32_t last_idnum;
+
+static int has_unshown_parent(struct commit *commit)
+{
+	struct commit_list *parent;
+
+	for (parent = commit->parents; parent; parent = parent->next)
+		if (!(parent->item->object.flags & SHOWN) &&
+		    !(parent->item->object.flags & UNINTERESTING))
+			return 1;
+	return 0;
+}
+
+/* Since intptr_t is C99, we do not use it here */
+static inline uint32_t *mark_to_ptr(uint32_t mark)
+{
+	return ((uint32_t *)NULL) + mark;
+}
+
+static inline uint32_t ptr_to_mark(void * mark)
+{
+	return (uint32_t *)mark - (uint32_t *)NULL;
+}
+
+static inline void mark_object(struct object *object, uint32_t mark)
+{
+	add_decoration(&idnums, object, mark_to_ptr(mark));
+}
+
+static inline void mark_next_object(struct object *object)
+{
+	mark_object(object, ++last_idnum);
+}
+
+static int get_object_mark(struct object *object)
+{
+	void *decoration = lookup_decoration(&idnums, object);
+	if (!decoration)
+		return 0;
+	return ptr_to_mark(decoration);
+}
+
+static void show_progress(void)
+{
+	static int counter = 0;
+	if (!progress)
+		return;
+	if ((++counter % progress) == 0)
+		printf("progress %d objects\n", counter);
+}
+
+static void handle_object(const unsigned char *sha1)
+{
+	unsigned long size;
+	enum object_type type;
+	char *buf;
+	struct object *object;
+
+	if (no_data)
+		return;
+
+	if (is_null_sha1(sha1))
+		return;
+
+	object = parse_object(sha1);
+	if (!object)
+		die ("Could not read blob %s", sha1_to_hex(sha1));
+
+	if (object->flags & SHOWN)
+		return;
+
+	buf = read_sha1_file(sha1, &type, &size);
+	if (!buf)
+		die ("Could not read blob %s", sha1_to_hex(sha1));
+
+	mark_next_object(object);
+
+	printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
+	if (size && fwrite(buf, size, 1, stdout) != 1)
+		die_errno ("Could not write blob '%s'", sha1_to_hex(sha1));
+	printf("\n");
+
+	show_progress();
+
+	object->flags |= SHOWN;
+	free(buf);
+}
+
+static void show_filemodify(struct diff_queue_struct *q,
+			    struct diff_options *options, void *data)
+{
+	int i;
+	for (i = 0; i < q->nr; i++) {
+		struct diff_filespec *ospec = q->queue[i]->one;
+		struct diff_filespec *spec = q->queue[i]->two;
+
+		switch (q->queue[i]->status) {
+		case DIFF_STATUS_DELETED:
+			printf("D %s\n", spec->path);
+			break;
+
+		case DIFF_STATUS_COPIED:
+		case DIFF_STATUS_RENAMED:
+			printf("%c \"%s\" \"%s\"\n", q->queue[i]->status,
+			       ospec->path, spec->path);
+
+			if (!hashcmp(ospec->sha1, spec->sha1) &&
+			    ospec->mode == spec->mode)
+				break;
+			/* fallthrough */
+
+		case DIFF_STATUS_TYPE_CHANGED:
+		case DIFF_STATUS_MODIFIED:
+		case DIFF_STATUS_ADDED:
+			/*
+			 * Links refer to objects in another repositories;
+			 * output the SHA-1 verbatim.
+			 */
+			if (no_data || S_ISGITLINK(spec->mode))
+				printf("M %06o %s %s\n", spec->mode,
+				       sha1_to_hex(spec->sha1), spec->path);
+			else {
+				struct object *object = lookup_object(spec->sha1);
+				printf("M %06o :%d %s\n", spec->mode,
+				       get_object_mark(object), spec->path);
+			}
+			break;
+
+		default:
+			die("Unexpected comparison status '%c' for %s, %s",
+				q->queue[i]->status,
+				ospec->path ? ospec->path : "none",
+				spec->path ? spec->path : "none");
+		}
+	}
+}
+
+static const char *find_encoding(const char *begin, const char *end)
+{
+	const char *needle = "\nencoding ";
+	char *bol, *eol;
+
+	bol = memmem(begin, end ? end - begin : strlen(begin),
+		     needle, strlen(needle));
+	if (!bol)
+		return git_commit_encoding;
+	bol += strlen(needle);
+	eol = strchrnul(bol, '\n');
+	*eol = '\0';
+	return bol;
+}
+
+static void handle_commit(struct commit *commit, struct rev_info *rev)
+{
+	int saved_output_format = rev->diffopt.output_format;
+	const char *author, *author_end, *committer, *committer_end;
+	const char *encoding, *message;
+	char *reencoded = NULL;
+	struct commit_list *p;
+	int i;
+
+	rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
+
+	parse_commit(commit);
+	author = strstr(commit->buffer, "\nauthor ");
+	if (!author)
+		die ("Could not find author in commit %s",
+		     sha1_to_hex(commit->object.sha1));
+	author++;
+	author_end = strchrnul(author, '\n');
+	committer = strstr(author_end, "\ncommitter ");
+	if (!committer)
+		die ("Could not find committer in commit %s",
+		     sha1_to_hex(commit->object.sha1));
+	committer++;
+	committer_end = strchrnul(committer, '\n');
+	message = strstr(committer_end, "\n\n");
+	encoding = find_encoding(committer_end, message);
+	if (message)
+		message += 2;
+
+	if (commit->parents &&
+	    get_object_mark(&commit->parents->item->object) != 0) {
+		parse_commit(commit->parents->item);
+		diff_tree_sha1(commit->parents->item->tree->object.sha1,
+			       commit->tree->object.sha1, "", &rev->diffopt);
+	}
+	else
+		diff_root_tree_sha1(commit->tree->object.sha1,
+				    "", &rev->diffopt);
+
+	/* Export the referenced blobs, and remember the marks. */
+	for (i = 0; i < diff_queued_diff.nr; i++)
+		if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
+			handle_object(diff_queued_diff.queue[i]->two->sha1);
+
+	mark_next_object(&commit->object);
+	if (!is_encoding_utf8(encoding))
+		reencoded = reencode_string(message, "UTF-8", encoding);
+	if (!commit->parents)
+		printf("reset %s\n", (const char*)commit->util);
+	printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
+	       (const char *)commit->util, last_idnum,
+	       (int)(author_end - author), author,
+	       (int)(committer_end - committer), committer,
+	       (unsigned)(reencoded
+			  ? strlen(reencoded) : message
+			  ? strlen(message) : 0),
+	       reencoded ? reencoded : message ? message : "");
+	free(reencoded);
+
+	for (i = 0, p = commit->parents; p; p = p->next) {
+		int mark = get_object_mark(&p->item->object);
+		if (!mark)
+			continue;
+		if (i == 0)
+			printf("from :%d\n", mark);
+		else
+			printf("merge :%d\n", mark);
+		i++;
+	}
+
+	log_tree_diff_flush(rev);
+	rev->diffopt.output_format = saved_output_format;
+
+	printf("\n");
+
+	show_progress();
+}
+
+static void handle_tail(struct object_array *commits, struct rev_info *revs)
+{
+	struct commit *commit;
+	while (commits->nr) {
+		commit = (struct commit *)commits->objects[commits->nr - 1].item;
+		if (has_unshown_parent(commit))
+			return;
+		handle_commit(commit, revs);
+		commits->nr--;
+	}
+}
+
+static void handle_tag(const char *name, struct tag *tag)
+{
+	unsigned long size;
+	enum object_type type;
+	char *buf;
+	const char *tagger, *tagger_end, *message;
+	size_t message_size = 0;
+	struct object *tagged;
+	int tagged_mark;
+	struct commit *p;
+
+	/* Trees have no identifer in fast-export output, thus we have no way
+	 * to output tags of trees, tags of tags of trees, etc.  Simply omit
+	 * such tags.
+	 */
+	tagged = tag->tagged;
+	while (tagged->type == OBJ_TAG) {
+		tagged = ((struct tag *)tagged)->tagged;
+	}
+	if (tagged->type == OBJ_TREE) {
+		warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
+			sha1_to_hex(tag->object.sha1));
+		return;
+	}
+
+	buf = read_sha1_file(tag->object.sha1, &type, &size);
+	if (!buf)
+		die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
+	message = memmem(buf, size, "\n\n", 2);
+	if (message) {
+		message += 2;
+		message_size = strlen(message);
+	}
+	tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
+	if (!tagger) {
+		if (fake_missing_tagger)
+			tagger = "tagger Unspecified Tagger "
+				"<unspecified-tagger> 0 +0000";
+		else
+			tagger = "";
+		tagger_end = tagger + strlen(tagger);
+	} else {
+		tagger++;
+		tagger_end = strchrnul(tagger, '\n');
+	}
+
+	/* handle signed tags */
+	if (message) {
+		const char *signature = strstr(message,
+					       "\n-----BEGIN PGP SIGNATURE-----\n");
+		if (signature)
+			switch(signed_tag_mode) {
+			case ABORT:
+				die ("Encountered signed tag %s; use "
+				     "--signed-tag=<mode> to handle it.",
+				     sha1_to_hex(tag->object.sha1));
+			case WARN:
+				warning ("Exporting signed tag %s",
+					 sha1_to_hex(tag->object.sha1));
+				/* fallthru */
+			case VERBATIM:
+				break;
+			case STRIP:
+				message_size = signature + 1 - message;
+				break;
+			}
+	}
+
+	/* handle tag->tagged having been filtered out due to paths specified */
+	tagged = tag->tagged;
+	tagged_mark = get_object_mark(tagged);
+	if (!tagged_mark) {
+		switch(tag_of_filtered_mode) {
+		case ABORT:
+			die ("Tag %s tags unexported object; use "
+			     "--tag-of-filtered-object=<mode> to handle it.",
+			     sha1_to_hex(tag->object.sha1));
+		case DROP:
+			/* Ignore this tag altogether */
+			return;
+		case REWRITE:
+			if (tagged->type != OBJ_COMMIT) {
+				die ("Tag %s tags unexported %s!",
+				     sha1_to_hex(tag->object.sha1),
+				     typename(tagged->type));
+			}
+			p = (struct commit *)tagged;
+			for (;;) {
+				if (p->parents && p->parents->next)
+					break;
+				if (p->object.flags & UNINTERESTING)
+					break;
+				if (!(p->object.flags & TREESAME))
+					break;
+				if (!p->parents)
+					die ("Can't find replacement commit for tag %s\n",
+					     sha1_to_hex(tag->object.sha1));
+				p = p->parents->item;
+			}
+			tagged_mark = get_object_mark(&p->object);
+		}
+	}
+
+	if (!prefixcmp(name, "refs/tags/"))
+		name += 10;
+	printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
+	       name, tagged_mark,
+	       (int)(tagger_end - tagger), tagger,
+	       tagger == tagger_end ? "" : "\n",
+	       (int)message_size, (int)message_size, message ? message : "");
+}
+
+static void get_tags_and_duplicates(struct object_array *pending,
+				    struct string_list *extra_refs)
+{
+	struct tag *tag;
+	int i;
+
+	for (i = 0; i < pending->nr; i++) {
+		struct object_array_entry *e = pending->objects + i;
+		unsigned char sha1[20];
+		struct commit *commit = commit;
+		char *full_name;
+
+		if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
+			continue;
+
+		switch (e->item->type) {
+		case OBJ_COMMIT:
+			commit = (struct commit *)e->item;
+			break;
+		case OBJ_TAG:
+			tag = (struct tag *)e->item;
+
+			/* handle nested tags */
+			while (tag && tag->object.type == OBJ_TAG) {
+				parse_object(tag->object.sha1);
+				string_list_append(full_name, extra_refs)->util = tag;
+				tag = (struct tag *)tag->tagged;
+			}
+			if (!tag)
+				die ("Tag %s points nowhere?", e->name);
+			switch(tag->object.type) {
+			case OBJ_COMMIT:
+				commit = (struct commit *)tag;
+				break;
+			case OBJ_BLOB:
+				handle_object(tag->object.sha1);
+				continue;
+			default: /* OBJ_TAG (nested tags) is already handled */
+				warning("Tag points to object of unexpected type %s, skipping.",
+					typename(tag->object.type));
+				continue;
+			}
+			break;
+		default:
+			warning("%s: Unexpected object of type %s, skipping.",
+				e->name,
+				typename(e->item->type));
+			continue;
+		}
+		if (commit->util)
+			/* more than one name for the same object */
+			string_list_append(full_name, extra_refs)->util = commit;
+		else
+			commit->util = full_name;
+	}
+}
+
+static void handle_tags_and_duplicates(struct string_list *extra_refs)
+{
+	struct commit *commit;
+	int i;
+
+	for (i = extra_refs->nr - 1; i >= 0; i--) {
+		const char *name = extra_refs->items[i].string;
+		struct object *object = extra_refs->items[i].util;
+		switch (object->type) {
+		case OBJ_TAG:
+			handle_tag(name, (struct tag *)object);
+			break;
+		case OBJ_COMMIT:
+			/* create refs pointing to already seen commits */
+			commit = (struct commit *)object;
+			printf("reset %s\nfrom :%d\n\n", name,
+			       get_object_mark(&commit->object));
+			show_progress();
+			break;
+		}
+	}
+}
+
+static void export_marks(char *file)
+{
+	unsigned int i;
+	uint32_t mark;
+	struct object_decoration *deco = idnums.hash;
+	FILE *f;
+	int e = 0;
+
+	f = fopen(file, "w");
+	if (!f)
+		error("Unable to open marks file %s for writing.", file);
+
+	for (i = 0; i < idnums.size; i++) {
+		if (deco->base && deco->base->type == 1) {
+			mark = ptr_to_mark(deco->decoration);
+			if (fprintf(f, ":%"PRIu32" %s\n", mark,
+				sha1_to_hex(deco->base->sha1)) < 0) {
+			    e = 1;
+			    break;
+			}
+		}
+		deco++;
+	}
+
+	e |= ferror(f);
+	e |= fclose(f);
+	if (e)
+		error("Unable to write marks file %s.", file);
+}
+
+static void import_marks(char *input_file)
+{
+	char line[512];
+	FILE *f = fopen(input_file, "r");
+	if (!f)
+		die_errno("cannot read '%s'", input_file);
+
+	while (fgets(line, sizeof(line), f)) {
+		uint32_t mark;
+		char *line_end, *mark_end;
+		unsigned char sha1[20];
+		struct object *object;
+
+		line_end = strchr(line, '\n');
+		if (line[0] != ':' || !line_end)
+			die("corrupt mark line: %s", line);
+		*line_end = '\0';
+
+		mark = strtoumax(line + 1, &mark_end, 10);
+		if (!mark || mark_end == line + 1
+			|| *mark_end != ' ' || get_sha1(mark_end + 1, sha1))
+			die("corrupt mark line: %s", line);
+
+		object = parse_object(sha1);
+		if (!object)
+			die ("Could not read blob %s", sha1_to_hex(sha1));
+
+		if (object->flags & SHOWN)
+			error("Object %s already has a mark", sha1);
+
+		mark_object(object, mark);
+		if (last_idnum < mark)
+			last_idnum = mark;
+
+		object->flags |= SHOWN;
+	}
+	fclose(f);
+}
+
+int cmd_fast_export(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info revs;
+	struct object_array commits = { 0, 0, NULL };
+	struct string_list extra_refs = { NULL, 0, 0, 0 };
+	struct commit *commit;
+	char *export_filename = NULL, *import_filename = NULL;
+	struct option options[] = {
+		OPT_INTEGER(0, "progress", &progress,
+			    "show progress after <n> objects"),
+		OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, "mode",
+			     "select handling of signed tags",
+			     parse_opt_signed_tag_mode),
+		OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, "mode",
+			     "select handling of tags that tag filtered objects",
+			     parse_opt_tag_of_filtered_mode),
+		OPT_STRING(0, "export-marks", &export_filename, "FILE",
+			     "Dump marks to this file"),
+		OPT_STRING(0, "import-marks", &import_filename, "FILE",
+			     "Import marks from this file"),
+		OPT_BOOLEAN(0, "fake-missing-tagger", &fake_missing_tagger,
+			     "Fake a tagger when tags lack one"),
+		{ OPTION_NEGBIT, 0, "data", &no_data, NULL,
+			"Skip output of blob data",
+			PARSE_OPT_NOARG | PARSE_OPT_NEGHELP, NULL, 1 },
+		OPT_END()
+	};
+
+	if (argc == 1)
+		usage_with_options (fast_export_usage, options);
+
+	/* we handle encodings */
+	git_config(git_default_config, NULL);
+
+	init_revisions(&revs, prefix);
+	revs.topo_order = 1;
+	revs.show_source = 1;
+	revs.rewrite_parents = 1;
+	argc = setup_revisions(argc, argv, &revs, NULL);
+	argc = parse_options(argc, argv, prefix, options, fast_export_usage, 0);
+	if (argc > 1)
+		usage_with_options (fast_export_usage, options);
+
+	if (import_filename)
+		import_marks(import_filename);
+
+	get_tags_and_duplicates(&revs.pending, &extra_refs);
+
+	if (prepare_revision_walk(&revs))
+		die("revision walk setup failed");
+	revs.diffopt.format_callback = show_filemodify;
+	DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
+	while ((commit = get_revision(&revs))) {
+		if (has_unshown_parent(commit)) {
+			add_object_array(&commit->object, NULL, &commits);
+		}
+		else {
+			handle_commit(commit, &revs);
+			handle_tail(&commits, &revs);
+		}
+	}
+
+	handle_tags_and_duplicates(&extra_refs);
+
+	if (export_filename)
+		export_marks(export_filename);
+
+	return 0;
+}
diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c
new file mode 100644
index 0000000..dbd8b7b
--- /dev/null
+++ b/builtin/fetch-pack.c
@@ -0,0 +1,976 @@
+#include "cache.h"
+#include "refs.h"
+#include "pkt-line.h"
+#include "commit.h"
+#include "tag.h"
+#include "exec_cmd.h"
+#include "pack.h"
+#include "sideband.h"
+#include "fetch-pack.h"
+#include "remote.h"
+#include "run-command.h"
+
+static int transfer_unpack_limit = -1;
+static int fetch_unpack_limit = -1;
+static int unpack_limit = 100;
+static int prefer_ofs_delta = 1;
+static struct fetch_pack_args args = {
+	/* .uploadpack = */ "git-upload-pack",
+};
+
+static const char fetch_pack_usage[] =
+"git fetch-pack [--all] [--quiet|-q] [--keep|-k] [--thin] [--include-tag] [--upload-pack=<git-upload-pack>] [--depth=<n>] [--no-progress] [-v] [<host>:]<directory> [<refs>...]";
+
+#define COMPLETE	(1U << 0)
+#define COMMON		(1U << 1)
+#define COMMON_REF	(1U << 2)
+#define SEEN		(1U << 3)
+#define POPPED		(1U << 4)
+
+static int marked;
+
+/*
+ * After sending this many "have"s if we do not get any new ACK , we
+ * give up traversing our history.
+ */
+#define MAX_IN_VAIN 256
+
+static struct commit_list *rev_list;
+static int non_common_revs, multi_ack, use_sideband;
+
+static void rev_list_push(struct commit *commit, int mark)
+{
+	if (!(commit->object.flags & mark)) {
+		commit->object.flags |= mark;
+
+		if (!(commit->object.parsed))
+			if (parse_commit(commit))
+				return;
+
+		insert_by_date(commit, &rev_list);
+
+		if (!(commit->object.flags & COMMON))
+			non_common_revs++;
+	}
+}
+
+static int rev_list_insert_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+	struct object *o = deref_tag(parse_object(sha1), path, 0);
+
+	if (o && o->type == OBJ_COMMIT)
+		rev_list_push((struct commit *)o, SEEN);
+
+	return 0;
+}
+
+static int clear_marks(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+	struct object *o = deref_tag(parse_object(sha1), path, 0);
+
+	if (o && o->type == OBJ_COMMIT)
+		clear_commit_marks((struct commit *)o,
+				   COMMON | COMMON_REF | SEEN | POPPED);
+	return 0;
+}
+
+/*
+   This function marks a rev and its ancestors as common.
+   In some cases, it is desirable to mark only the ancestors (for example
+   when only the server does not yet know that they are common).
+*/
+
+static void mark_common(struct commit *commit,
+		int ancestors_only, int dont_parse)
+{
+	if (commit != NULL && !(commit->object.flags & COMMON)) {
+		struct object *o = (struct object *)commit;
+
+		if (!ancestors_only)
+			o->flags |= COMMON;
+
+		if (!(o->flags & SEEN))
+			rev_list_push(commit, SEEN);
+		else {
+			struct commit_list *parents;
+
+			if (!ancestors_only && !(o->flags & POPPED))
+				non_common_revs--;
+			if (!o->parsed && !dont_parse)
+				if (parse_commit(commit))
+					return;
+
+			for (parents = commit->parents;
+					parents;
+					parents = parents->next)
+				mark_common(parents->item, 0, dont_parse);
+		}
+	}
+}
+
+/*
+  Get the next rev to send, ignoring the common.
+*/
+
+static const unsigned char *get_rev(void)
+{
+	struct commit *commit = NULL;
+
+	while (commit == NULL) {
+		unsigned int mark;
+		struct commit_list *parents;
+
+		if (rev_list == NULL || non_common_revs == 0)
+			return NULL;
+
+		commit = rev_list->item;
+		if (!commit->object.parsed)
+			parse_commit(commit);
+		parents = commit->parents;
+
+		commit->object.flags |= POPPED;
+		if (!(commit->object.flags & COMMON))
+			non_common_revs--;
+
+		if (commit->object.flags & COMMON) {
+			/* do not send "have", and ignore ancestors */
+			commit = NULL;
+			mark = COMMON | SEEN;
+		} else if (commit->object.flags & COMMON_REF)
+			/* send "have", and ignore ancestors */
+			mark = COMMON | SEEN;
+		else
+			/* send "have", also for its ancestors */
+			mark = SEEN;
+
+		while (parents) {
+			if (!(parents->item->object.flags & SEEN))
+				rev_list_push(parents->item, mark);
+			if (mark & COMMON)
+				mark_common(parents->item, 1, 0);
+			parents = parents->next;
+		}
+
+		rev_list = rev_list->next;
+	}
+
+	return commit->object.sha1;
+}
+
+enum ack_type {
+	NAK = 0,
+	ACK,
+	ACK_continue,
+	ACK_common,
+	ACK_ready
+};
+
+static void consume_shallow_list(int fd)
+{
+	if (args.stateless_rpc && args.depth > 0) {
+		/* If we sent a depth we will get back "duplicate"
+		 * shallow and unshallow commands every time there
+		 * is a block of have lines exchanged.
+		 */
+		char line[1000];
+		while (packet_read_line(fd, line, sizeof(line))) {
+			if (!prefixcmp(line, "shallow "))
+				continue;
+			if (!prefixcmp(line, "unshallow "))
+				continue;
+			die("git fetch-pack: expected shallow list");
+		}
+	}
+}
+
+static enum ack_type get_ack(int fd, unsigned char *result_sha1)
+{
+	static char line[1000];
+	int len = packet_read_line(fd, line, sizeof(line));
+
+	if (!len)
+		die("git fetch-pack: expected ACK/NAK, got EOF");
+	if (line[len-1] == '\n')
+		line[--len] = 0;
+	if (!strcmp(line, "NAK"))
+		return NAK;
+	if (!prefixcmp(line, "ACK ")) {
+		if (!get_sha1_hex(line+4, result_sha1)) {
+			if (strstr(line+45, "continue"))
+				return ACK_continue;
+			if (strstr(line+45, "common"))
+				return ACK_common;
+			if (strstr(line+45, "ready"))
+				return ACK_ready;
+			return ACK;
+		}
+	}
+	die("git fetch_pack: expected ACK/NAK, got '%s'", line);
+}
+
+static void send_request(int fd, struct strbuf *buf)
+{
+	if (args.stateless_rpc) {
+		send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
+		packet_flush(fd);
+	} else
+		safe_write(fd, buf->buf, buf->len);
+}
+
+static int find_common(int fd[2], unsigned char *result_sha1,
+		       struct ref *refs)
+{
+	int fetching;
+	int count = 0, flushes = 0, retval;
+	const unsigned char *sha1;
+	unsigned in_vain = 0;
+	int got_continue = 0;
+	struct strbuf req_buf = STRBUF_INIT;
+	size_t state_len = 0;
+
+	if (args.stateless_rpc && multi_ack == 1)
+		die("--stateless-rpc requires multi_ack_detailed");
+	if (marked)
+		for_each_ref(clear_marks, NULL);
+	marked = 1;
+
+	for_each_ref(rev_list_insert_ref, NULL);
+
+	fetching = 0;
+	for ( ; refs ; refs = refs->next) {
+		unsigned char *remote = refs->old_sha1;
+		const char *remote_hex;
+		struct object *o;
+
+		/*
+		 * If that object is complete (i.e. it is an ancestor of a
+		 * local ref), we tell them we have it but do not have to
+		 * tell them about its ancestors, which they already know
+		 * about.
+		 *
+		 * We use lookup_object here because we are only
+		 * interested in the case we *know* the object is
+		 * reachable and we have already scanned it.
+		 */
+		if (((o = lookup_object(remote)) != NULL) &&
+				(o->flags & COMPLETE)) {
+			continue;
+		}
+
+		remote_hex = sha1_to_hex(remote);
+		if (!fetching) {
+			struct strbuf c = STRBUF_INIT;
+			if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
+			if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
+			if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
+			if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
+			if (args.use_thin_pack) strbuf_addstr(&c, " thin-pack");
+			if (args.no_progress)   strbuf_addstr(&c, " no-progress");
+			if (args.include_tag)   strbuf_addstr(&c, " include-tag");
+			if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
+			packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
+			strbuf_release(&c);
+		} else
+			packet_buf_write(&req_buf, "want %s\n", remote_hex);
+		fetching++;
+	}
+
+	if (!fetching) {
+		strbuf_release(&req_buf);
+		packet_flush(fd[1]);
+		return 1;
+	}
+
+	if (is_repository_shallow())
+		write_shallow_commits(&req_buf, 1);
+	if (args.depth > 0)
+		packet_buf_write(&req_buf, "deepen %d", args.depth);
+	packet_buf_flush(&req_buf);
+	state_len = req_buf.len;
+
+	if (args.depth > 0) {
+		char line[1024];
+		unsigned char sha1[20];
+
+		send_request(fd[1], &req_buf);
+		while (packet_read_line(fd[0], line, sizeof(line))) {
+			if (!prefixcmp(line, "shallow ")) {
+				if (get_sha1_hex(line + 8, sha1))
+					die("invalid shallow line: %s", line);
+				register_shallow(sha1);
+				continue;
+			}
+			if (!prefixcmp(line, "unshallow ")) {
+				if (get_sha1_hex(line + 10, sha1))
+					die("invalid unshallow line: %s", line);
+				if (!lookup_object(sha1))
+					die("object not found: %s", line);
+				/* make sure that it is parsed as shallow */
+				if (!parse_object(sha1))
+					die("error in object: %s", line);
+				if (unregister_shallow(sha1))
+					die("no shallow found: %s", line);
+				continue;
+			}
+			die("expected shallow/unshallow, got %s", line);
+		}
+	} else if (!args.stateless_rpc)
+		send_request(fd[1], &req_buf);
+
+	if (!args.stateless_rpc) {
+		/* If we aren't using the stateless-rpc interface
+		 * we don't need to retain the headers.
+		 */
+		strbuf_setlen(&req_buf, 0);
+		state_len = 0;
+	}
+
+	flushes = 0;
+	retval = -1;
+	while ((sha1 = get_rev())) {
+		packet_buf_write(&req_buf, "have %s\n", sha1_to_hex(sha1));
+		if (args.verbose)
+			fprintf(stderr, "have %s\n", sha1_to_hex(sha1));
+		in_vain++;
+		if (!(31 & ++count)) {
+			int ack;
+
+			packet_buf_flush(&req_buf);
+			send_request(fd[1], &req_buf);
+			strbuf_setlen(&req_buf, state_len);
+			flushes++;
+
+			/*
+			 * We keep one window "ahead" of the other side, and
+			 * will wait for an ACK only on the next one
+			 */
+			if (!args.stateless_rpc && count == 32)
+				continue;
+
+			consume_shallow_list(fd[0]);
+			do {
+				ack = get_ack(fd[0], result_sha1);
+				if (args.verbose && ack)
+					fprintf(stderr, "got ack %d %s\n", ack,
+							sha1_to_hex(result_sha1));
+				switch (ack) {
+				case ACK:
+					flushes = 0;
+					multi_ack = 0;
+					retval = 0;
+					goto done;
+				case ACK_common:
+				case ACK_ready:
+				case ACK_continue: {
+					struct commit *commit =
+						lookup_commit(result_sha1);
+					if (args.stateless_rpc
+					 && ack == ACK_common
+					 && !(commit->object.flags & COMMON)) {
+						/* We need to replay the have for this object
+						 * on the next RPC request so the peer knows
+						 * it is in common with us.
+						 */
+						const char *hex = sha1_to_hex(result_sha1);
+						packet_buf_write(&req_buf, "have %s\n", hex);
+						state_len = req_buf.len;
+					}
+					mark_common(commit, 0, 1);
+					retval = 0;
+					in_vain = 0;
+					got_continue = 1;
+					break;
+					}
+				}
+			} while (ack);
+			flushes--;
+			if (got_continue && MAX_IN_VAIN < in_vain) {
+				if (args.verbose)
+					fprintf(stderr, "giving up\n");
+				break; /* give up */
+			}
+		}
+	}
+done:
+	packet_buf_write(&req_buf, "done\n");
+	send_request(fd[1], &req_buf);
+	if (args.verbose)
+		fprintf(stderr, "done\n");
+	if (retval != 0) {
+		multi_ack = 0;
+		flushes++;
+	}
+	strbuf_release(&req_buf);
+
+	consume_shallow_list(fd[0]);
+	while (flushes || multi_ack) {
+		int ack = get_ack(fd[0], result_sha1);
+		if (ack) {
+			if (args.verbose)
+				fprintf(stderr, "got ack (%d) %s\n", ack,
+					sha1_to_hex(result_sha1));
+			if (ack == ACK)
+				return 0;
+			multi_ack = 1;
+			continue;
+		}
+		flushes--;
+	}
+	/* it is no error to fetch into a completely empty repo */
+	return count ? retval : 0;
+}
+
+static struct commit_list *complete;
+
+static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+	struct object *o = parse_object(sha1);
+
+	while (o && o->type == OBJ_TAG) {
+		struct tag *t = (struct tag *) o;
+		if (!t->tagged)
+			break; /* broken repository */
+		o->flags |= COMPLETE;
+		o = parse_object(t->tagged->sha1);
+	}
+	if (o && o->type == OBJ_COMMIT) {
+		struct commit *commit = (struct commit *)o;
+		commit->object.flags |= COMPLETE;
+		insert_by_date(commit, &complete);
+	}
+	return 0;
+}
+
+static void mark_recent_complete_commits(unsigned long cutoff)
+{
+	while (complete && cutoff <= complete->item->date) {
+		if (args.verbose)
+			fprintf(stderr, "Marking %s as complete\n",
+				sha1_to_hex(complete->item->object.sha1));
+		pop_most_recent_commit(&complete, COMPLETE);
+	}
+}
+
+static void filter_refs(struct ref **refs, int nr_match, char **match)
+{
+	struct ref **return_refs;
+	struct ref *newlist = NULL;
+	struct ref **newtail = &newlist;
+	struct ref *ref, *next;
+	struct ref *fastarray[32];
+
+	if (nr_match && !args.fetch_all) {
+		if (ARRAY_SIZE(fastarray) < nr_match)
+			return_refs = xcalloc(nr_match, sizeof(struct ref *));
+		else {
+			return_refs = fastarray;
+			memset(return_refs, 0, sizeof(struct ref *) * nr_match);
+		}
+	}
+	else
+		return_refs = NULL;
+
+	for (ref = *refs; ref; ref = next) {
+		next = ref->next;
+		if (!memcmp(ref->name, "refs/", 5) &&
+		    check_ref_format(ref->name + 5))
+			; /* trash */
+		else if (args.fetch_all &&
+			 (!args.depth || prefixcmp(ref->name, "refs/tags/") )) {
+			*newtail = ref;
+			ref->next = NULL;
+			newtail = &ref->next;
+			continue;
+		}
+		else {
+			int order = path_match(ref->name, nr_match, match);
+			if (order) {
+				return_refs[order-1] = ref;
+				continue; /* we will link it later */
+			}
+		}
+		free(ref);
+	}
+
+	if (!args.fetch_all) {
+		int i;
+		for (i = 0; i < nr_match; i++) {
+			ref = return_refs[i];
+			if (ref) {
+				*newtail = ref;
+				ref->next = NULL;
+				newtail = &ref->next;
+			}
+		}
+		if (return_refs != fastarray)
+			free(return_refs);
+	}
+	*refs = newlist;
+}
+
+static int everything_local(struct ref **refs, int nr_match, char **match)
+{
+	struct ref *ref;
+	int retval;
+	unsigned long cutoff = 0;
+
+	save_commit_buffer = 0;
+
+	for (ref = *refs; ref; ref = ref->next) {
+		struct object *o;
+
+		o = parse_object(ref->old_sha1);
+		if (!o)
+			continue;
+
+		/* We already have it -- which may mean that we were
+		 * in sync with the other side at some time after
+		 * that (it is OK if we guess wrong here).
+		 */
+		if (o->type == OBJ_COMMIT) {
+			struct commit *commit = (struct commit *)o;
+			if (!cutoff || cutoff < commit->date)
+				cutoff = commit->date;
+		}
+	}
+
+	if (!args.depth) {
+		for_each_ref(mark_complete, NULL);
+		if (cutoff)
+			mark_recent_complete_commits(cutoff);
+	}
+
+	/*
+	 * Mark all complete remote refs as common refs.
+	 * Don't mark them common yet; the server has to be told so first.
+	 */
+	for (ref = *refs; ref; ref = ref->next) {
+		struct object *o = deref_tag(lookup_object(ref->old_sha1),
+					     NULL, 0);
+
+		if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
+			continue;
+
+		if (!(o->flags & SEEN)) {
+			rev_list_push((struct commit *)o, COMMON_REF | SEEN);
+
+			mark_common((struct commit *)o, 1, 1);
+		}
+	}
+
+	filter_refs(refs, nr_match, match);
+
+	for (retval = 1, ref = *refs; ref ; ref = ref->next) {
+		const unsigned char *remote = ref->old_sha1;
+		unsigned char local[20];
+		struct object *o;
+
+		o = lookup_object(remote);
+		if (!o || !(o->flags & COMPLETE)) {
+			retval = 0;
+			if (!args.verbose)
+				continue;
+			fprintf(stderr,
+				"want %s (%s)\n", sha1_to_hex(remote),
+				ref->name);
+			continue;
+		}
+
+		hashcpy(ref->new_sha1, local);
+		if (!args.verbose)
+			continue;
+		fprintf(stderr,
+			"already have %s (%s)\n", sha1_to_hex(remote),
+			ref->name);
+	}
+	return retval;
+}
+
+static int sideband_demux(int in, int out, void *data)
+{
+	int *xd = data;
+
+	int ret = recv_sideband("fetch-pack", xd[0], out);
+	close(out);
+	return ret;
+}
+
+static int get_pack(int xd[2], char **pack_lockfile)
+{
+	struct async demux;
+	const char *argv[20];
+	char keep_arg[256];
+	char hdr_arg[256];
+	const char **av;
+	int do_keep = args.keep_pack;
+	struct child_process cmd;
+
+	memset(&demux, 0, sizeof(demux));
+	if (use_sideband) {
+		/* xd[] is talking with upload-pack; subprocess reads from
+		 * xd[0], spits out band#2 to stderr, and feeds us band#1
+		 * through demux->out.
+		 */
+		demux.proc = sideband_demux;
+		demux.data = xd;
+		demux.out = -1;
+		if (start_async(&demux))
+			die("fetch-pack: unable to fork off sideband"
+			    " demultiplexer");
+	}
+	else
+		demux.out = xd[0];
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.argv = argv;
+	av = argv;
+	*hdr_arg = 0;
+	if (!args.keep_pack && unpack_limit) {
+		struct pack_header header;
+
+		if (read_pack_header(demux.out, &header))
+			die("protocol error: bad pack header");
+		snprintf(hdr_arg, sizeof(hdr_arg),
+			 "--pack_header=%"PRIu32",%"PRIu32,
+			 ntohl(header.hdr_version), ntohl(header.hdr_entries));
+		if (ntohl(header.hdr_entries) < unpack_limit)
+			do_keep = 0;
+		else
+			do_keep = 1;
+	}
+
+	if (do_keep) {
+		if (pack_lockfile)
+			cmd.out = -1;
+		*av++ = "index-pack";
+		*av++ = "--stdin";
+		if (!args.quiet && !args.no_progress)
+			*av++ = "-v";
+		if (args.use_thin_pack)
+			*av++ = "--fix-thin";
+		if (args.lock_pack || unpack_limit) {
+			int s = sprintf(keep_arg,
+					"--keep=fetch-pack %"PRIuMAX " on ", (uintmax_t) getpid());
+			if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
+				strcpy(keep_arg + s, "localhost");
+			*av++ = keep_arg;
+		}
+	}
+	else {
+		*av++ = "unpack-objects";
+		if (args.quiet)
+			*av++ = "-q";
+	}
+	if (*hdr_arg)
+		*av++ = hdr_arg;
+	*av++ = NULL;
+
+	cmd.in = demux.out;
+	cmd.git_cmd = 1;
+	if (start_command(&cmd))
+		die("fetch-pack: unable to fork off %s", argv[0]);
+	if (do_keep && pack_lockfile) {
+		*pack_lockfile = index_pack_lockfile(cmd.out);
+		close(cmd.out);
+	}
+
+	if (finish_command(&cmd))
+		die("%s failed", argv[0]);
+	if (use_sideband && finish_async(&demux))
+		die("error in sideband demultiplexer");
+	return 0;
+}
+
+static struct ref *do_fetch_pack(int fd[2],
+		const struct ref *orig_ref,
+		int nr_match,
+		char **match,
+		char **pack_lockfile)
+{
+	struct ref *ref = copy_ref_list(orig_ref);
+	unsigned char sha1[20];
+
+	if (is_repository_shallow() && !server_supports("shallow"))
+		die("Server does not support shallow clients");
+	if (server_supports("multi_ack_detailed")) {
+		if (args.verbose)
+			fprintf(stderr, "Server supports multi_ack_detailed\n");
+		multi_ack = 2;
+	}
+	else if (server_supports("multi_ack")) {
+		if (args.verbose)
+			fprintf(stderr, "Server supports multi_ack\n");
+		multi_ack = 1;
+	}
+	if (server_supports("side-band-64k")) {
+		if (args.verbose)
+			fprintf(stderr, "Server supports side-band-64k\n");
+		use_sideband = 2;
+	}
+	else if (server_supports("side-band")) {
+		if (args.verbose)
+			fprintf(stderr, "Server supports side-band\n");
+		use_sideband = 1;
+	}
+	if (server_supports("ofs-delta")) {
+		if (args.verbose)
+			fprintf(stderr, "Server supports ofs-delta\n");
+	} else
+		prefer_ofs_delta = 0;
+	if (everything_local(&ref, nr_match, match)) {
+		packet_flush(fd[1]);
+		goto all_done;
+	}
+	if (find_common(fd, sha1, ref) < 0)
+		if (!args.keep_pack)
+			/* When cloning, it is not unusual to have
+			 * no common commit.
+			 */
+			warning("no common commits");
+
+	if (args.stateless_rpc)
+		packet_flush(fd[1]);
+	if (get_pack(fd, pack_lockfile))
+		die("git fetch-pack: fetch failed.");
+
+ all_done:
+	return ref;
+}
+
+static int remove_duplicates(int nr_heads, char **heads)
+{
+	int src, dst;
+
+	for (src = dst = 0; src < nr_heads; src++) {
+		/* If heads[src] is different from any of
+		 * heads[0..dst], push it in.
+		 */
+		int i;
+		for (i = 0; i < dst; i++) {
+			if (!strcmp(heads[i], heads[src]))
+				break;
+		}
+		if (i < dst)
+			continue;
+		if (src != dst)
+			heads[dst] = heads[src];
+		dst++;
+	}
+	return dst;
+}
+
+static int fetch_pack_config(const char *var, const char *value, void *cb)
+{
+	if (strcmp(var, "fetch.unpacklimit") == 0) {
+		fetch_unpack_limit = git_config_int(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "transfer.unpacklimit") == 0) {
+		transfer_unpack_limit = git_config_int(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "repack.usedeltabaseoffset") == 0) {
+		prefer_ofs_delta = git_config_bool(var, value);
+		return 0;
+	}
+
+	return git_default_config(var, value, cb);
+}
+
+static struct lock_file lock;
+
+static void fetch_pack_setup(void)
+{
+	static int did_setup;
+	if (did_setup)
+		return;
+	git_config(fetch_pack_config, NULL);
+	if (0 <= transfer_unpack_limit)
+		unpack_limit = transfer_unpack_limit;
+	else if (0 <= fetch_unpack_limit)
+		unpack_limit = fetch_unpack_limit;
+	did_setup = 1;
+}
+
+int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
+{
+	int i, ret, nr_heads;
+	struct ref *ref = NULL;
+	char *dest = NULL, **heads;
+	int fd[2];
+	char *pack_lockfile = NULL;
+	char **pack_lockfile_ptr = NULL;
+	struct child_process *conn;
+
+	nr_heads = 0;
+	heads = NULL;
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (*arg == '-') {
+			if (!prefixcmp(arg, "--upload-pack=")) {
+				args.uploadpack = arg + 14;
+				continue;
+			}
+			if (!prefixcmp(arg, "--exec=")) {
+				args.uploadpack = arg + 7;
+				continue;
+			}
+			if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) {
+				args.quiet = 1;
+				continue;
+			}
+			if (!strcmp("--keep", arg) || !strcmp("-k", arg)) {
+				args.lock_pack = args.keep_pack;
+				args.keep_pack = 1;
+				continue;
+			}
+			if (!strcmp("--thin", arg)) {
+				args.use_thin_pack = 1;
+				continue;
+			}
+			if (!strcmp("--include-tag", arg)) {
+				args.include_tag = 1;
+				continue;
+			}
+			if (!strcmp("--all", arg)) {
+				args.fetch_all = 1;
+				continue;
+			}
+			if (!strcmp("-v", arg)) {
+				args.verbose = 1;
+				continue;
+			}
+			if (!prefixcmp(arg, "--depth=")) {
+				args.depth = strtol(arg + 8, NULL, 0);
+				continue;
+			}
+			if (!strcmp("--no-progress", arg)) {
+				args.no_progress = 1;
+				continue;
+			}
+			if (!strcmp("--stateless-rpc", arg)) {
+				args.stateless_rpc = 1;
+				continue;
+			}
+			if (!strcmp("--lock-pack", arg)) {
+				args.lock_pack = 1;
+				pack_lockfile_ptr = &pack_lockfile;
+				continue;
+			}
+			usage(fetch_pack_usage);
+		}
+		dest = (char *)arg;
+		heads = (char **)(argv + i + 1);
+		nr_heads = argc - i - 1;
+		break;
+	}
+	if (!dest)
+		usage(fetch_pack_usage);
+
+	if (args.stateless_rpc) {
+		conn = NULL;
+		fd[0] = 0;
+		fd[1] = 1;
+	} else {
+		conn = git_connect(fd, (char *)dest, args.uploadpack,
+				   args.verbose ? CONNECT_VERBOSE : 0);
+	}
+
+	get_remote_heads(fd[0], &ref, 0, NULL, 0, NULL);
+
+	ref = fetch_pack(&args, fd, conn, ref, dest,
+		nr_heads, heads, pack_lockfile_ptr);
+	if (pack_lockfile) {
+		printf("lock %s\n", pack_lockfile);
+		fflush(stdout);
+	}
+	close(fd[0]);
+	close(fd[1]);
+	if (finish_connect(conn))
+		ref = NULL;
+	ret = !ref;
+
+	if (!ret && nr_heads) {
+		/* If the heads to pull were given, we should have
+		 * consumed all of them by matching the remote.
+		 * Otherwise, 'git fetch remote no-such-ref' would
+		 * silently succeed without issuing an error.
+		 */
+		for (i = 0; i < nr_heads; i++)
+			if (heads[i] && heads[i][0]) {
+				error("no such remote ref %s", heads[i]);
+				ret = 1;
+			}
+	}
+	while (ref) {
+		printf("%s %s\n",
+		       sha1_to_hex(ref->old_sha1), ref->name);
+		ref = ref->next;
+	}
+
+	return ret;
+}
+
+struct ref *fetch_pack(struct fetch_pack_args *my_args,
+		       int fd[], struct child_process *conn,
+		       const struct ref *ref,
+		const char *dest,
+		int nr_heads,
+		char **heads,
+		char **pack_lockfile)
+{
+	struct stat st;
+	struct ref *ref_cpy;
+
+	fetch_pack_setup();
+	if (&args != my_args)
+		memcpy(&args, my_args, sizeof(args));
+	if (args.depth > 0) {
+		if (stat(git_path("shallow"), &st))
+			st.st_mtime = 0;
+	}
+
+	if (heads && nr_heads)
+		nr_heads = remove_duplicates(nr_heads, heads);
+	if (!ref) {
+		packet_flush(fd[1]);
+		die("no matching remote head");
+	}
+	ref_cpy = do_fetch_pack(fd, ref, nr_heads, heads, pack_lockfile);
+
+	if (args.depth > 0) {
+		struct cache_time mtime;
+		struct strbuf sb = STRBUF_INIT;
+		char *shallow = git_path("shallow");
+		int fd;
+
+		mtime.sec = st.st_mtime;
+		mtime.nsec = ST_MTIME_NSEC(st);
+		if (stat(shallow, &st)) {
+			if (mtime.sec)
+				die("shallow file was removed during fetch");
+		} else if (st.st_mtime != mtime.sec
+#ifdef USE_NSEC
+				|| ST_MTIME_NSEC(st) != mtime.nsec
+#endif
+			  )
+			die("shallow file was changed during fetch");
+
+		fd = hold_lock_file_for_update(&lock, shallow,
+					       LOCK_DIE_ON_ERROR);
+		if (!write_shallow_commits(&sb, 0)
+		 || write_in_full(fd, sb.buf, sb.len) != sb.len) {
+			unlink_or_warn(shallow);
+			rollback_lock_file(&lock);
+		} else {
+			commit_lock_file(&lock);
+		}
+		strbuf_release(&sb);
+	}
+
+	reprepare_packed_git();
+	return ref_cpy;
+}
diff --git a/builtin/fetch.c b/builtin/fetch.c
new file mode 100644
index 0000000..b6c5b34
--- /dev/null
+++ b/builtin/fetch.c
@@ -0,0 +1,942 @@
+/*
+ * "git fetch"
+ */
+#include "cache.h"
+#include "refs.h"
+#include "commit.h"
+#include "builtin.h"
+#include "string-list.h"
+#include "remote.h"
+#include "transport.h"
+#include "run-command.h"
+#include "parse-options.h"
+#include "sigchain.h"
+#include "transport.h"
+
+static const char * const builtin_fetch_usage[] = {
+	"git fetch [options] [<repository> <refspec>...]",
+	"git fetch [options] <group>",
+	"git fetch --multiple [options] [<repository> | <group>]...",
+	"git fetch --all [options]",
+	NULL
+};
+
+enum {
+	TAGS_UNSET = 0,
+	TAGS_DEFAULT = 1,
+	TAGS_SET = 2
+};
+
+static int all, append, dry_run, force, keep, multiple, prune, update_head_ok, verbosity;
+static int tags = TAGS_DEFAULT;
+static const char *depth;
+static const char *upload_pack;
+static struct strbuf default_rla = STRBUF_INIT;
+static struct transport *transport;
+
+static struct option builtin_fetch_options[] = {
+	OPT__VERBOSITY(&verbosity),
+	OPT_BOOLEAN(0, "all", &all,
+		    "fetch from all remotes"),
+	OPT_BOOLEAN('a', "append", &append,
+		    "append to .git/FETCH_HEAD instead of overwriting"),
+	OPT_STRING(0, "upload-pack", &upload_pack, "PATH",
+		   "path to upload pack on remote end"),
+	OPT_BOOLEAN('f', "force", &force,
+		    "force overwrite of local branch"),
+	OPT_BOOLEAN('m', "multiple", &multiple,
+		    "fetch from multiple remotes"),
+	OPT_SET_INT('t', "tags", &tags,
+		    "fetch all tags and associated objects", TAGS_SET),
+	OPT_SET_INT('n', NULL, &tags,
+		    "do not fetch all tags (--no-tags)", TAGS_UNSET),
+	OPT_BOOLEAN('p', "prune", &prune,
+		    "prune tracking branches no longer on remote"),
+	OPT_BOOLEAN(0, "dry-run", &dry_run,
+		    "dry run"),
+	OPT_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
+	OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
+		    "allow updating of HEAD ref"),
+	OPT_STRING(0, "depth", &depth, "DEPTH",
+		   "deepen history of shallow clone"),
+	OPT_END()
+};
+
+static void unlock_pack(void)
+{
+	if (transport)
+		transport_unlock_pack(transport);
+}
+
+static void unlock_pack_on_signal(int signo)
+{
+	unlock_pack();
+	sigchain_pop(signo);
+	raise(signo);
+}
+
+static void add_merge_config(struct ref **head,
+			   const struct ref *remote_refs,
+		           struct branch *branch,
+		           struct ref ***tail)
+{
+	int i;
+
+	for (i = 0; i < branch->merge_nr; i++) {
+		struct ref *rm, **old_tail = *tail;
+		struct refspec refspec;
+
+		for (rm = *head; rm; rm = rm->next) {
+			if (branch_merge_matches(branch, i, rm->name)) {
+				rm->merge = 1;
+				break;
+			}
+		}
+		if (rm)
+			continue;
+
+		/*
+		 * Not fetched to a tracking branch?  We need to fetch
+		 * it anyway to allow this branch's "branch.$name.merge"
+		 * to be honored by 'git pull', but we do not have to
+		 * fail if branch.$name.merge is misconfigured to point
+		 * at a nonexisting branch.  If we were indeed called by
+		 * 'git pull', it will notice the misconfiguration because
+		 * there is no entry in the resulting FETCH_HEAD marked
+		 * for merging.
+		 */
+		refspec.src = branch->merge[i]->src;
+		refspec.dst = NULL;
+		refspec.pattern = 0;
+		refspec.force = 0;
+		get_fetch_map(remote_refs, &refspec, tail, 1);
+		for (rm = *old_tail; rm; rm = rm->next)
+			rm->merge = 1;
+	}
+}
+
+static void find_non_local_tags(struct transport *transport,
+			struct ref **head,
+			struct ref ***tail);
+
+static struct ref *get_ref_map(struct transport *transport,
+			       struct refspec *refs, int ref_count, int tags,
+			       int *autotags)
+{
+	int i;
+	struct ref *rm;
+	struct ref *ref_map = NULL;
+	struct ref **tail = &ref_map;
+
+	const struct ref *remote_refs = transport_get_remote_refs(transport);
+
+	if (ref_count || tags == TAGS_SET) {
+		for (i = 0; i < ref_count; i++) {
+			get_fetch_map(remote_refs, &refs[i], &tail, 0);
+			if (refs[i].dst && refs[i].dst[0])
+				*autotags = 1;
+		}
+		/* Merge everything on the command line, but not --tags */
+		for (rm = ref_map; rm; rm = rm->next)
+			rm->merge = 1;
+		if (tags == TAGS_SET)
+			get_fetch_map(remote_refs, tag_refspec, &tail, 0);
+	} else {
+		/* Use the defaults */
+		struct remote *remote = transport->remote;
+		struct branch *branch = branch_get(NULL);
+		int has_merge = branch_has_merge_config(branch);
+		if (remote && (remote->fetch_refspec_nr || has_merge)) {
+			for (i = 0; i < remote->fetch_refspec_nr; i++) {
+				get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
+				if (remote->fetch[i].dst &&
+				    remote->fetch[i].dst[0])
+					*autotags = 1;
+				if (!i && !has_merge && ref_map &&
+				    !remote->fetch[0].pattern)
+					ref_map->merge = 1;
+			}
+			/*
+			 * if the remote we're fetching from is the same
+			 * as given in branch.<name>.remote, we add the
+			 * ref given in branch.<name>.merge, too.
+			 */
+			if (has_merge &&
+			    !strcmp(branch->remote_name, remote->name))
+				add_merge_config(&ref_map, remote_refs, branch, &tail);
+		} else {
+			ref_map = get_remote_ref(remote_refs, "HEAD");
+			if (!ref_map)
+				die("Couldn't find remote ref HEAD");
+			ref_map->merge = 1;
+			tail = &ref_map->next;
+		}
+	}
+	if (tags == TAGS_DEFAULT && *autotags)
+		find_non_local_tags(transport, &ref_map, &tail);
+	ref_remove_duplicates(ref_map);
+
+	return ref_map;
+}
+
+#define STORE_REF_ERROR_OTHER 1
+#define STORE_REF_ERROR_DF_CONFLICT 2
+
+static int s_update_ref(const char *action,
+			struct ref *ref,
+			int check_old)
+{
+	char msg[1024];
+	char *rla = getenv("GIT_REFLOG_ACTION");
+	static struct ref_lock *lock;
+
+	if (dry_run)
+		return 0;
+	if (!rla)
+		rla = default_rla.buf;
+	snprintf(msg, sizeof(msg), "%s: %s", rla, action);
+	lock = lock_any_ref_for_update(ref->name,
+				       check_old ? ref->old_sha1 : NULL, 0);
+	if (!lock)
+		return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
+					  STORE_REF_ERROR_OTHER;
+	if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
+		return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
+					  STORE_REF_ERROR_OTHER;
+	return 0;
+}
+
+#define REFCOL_WIDTH  10
+
+static int update_local_ref(struct ref *ref,
+			    const char *remote,
+			    char *display)
+{
+	struct commit *current = NULL, *updated;
+	enum object_type type;
+	struct branch *current_branch = branch_get(NULL);
+	const char *pretty_ref = prettify_refname(ref->name);
+
+	*display = 0;
+	type = sha1_object_info(ref->new_sha1, NULL);
+	if (type < 0)
+		die("object %s not found", sha1_to_hex(ref->new_sha1));
+
+	if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
+		if (verbosity > 0)
+			sprintf(display, "= %-*s %-*s -> %s", TRANSPORT_SUMMARY_WIDTH,
+				"[up to date]", REFCOL_WIDTH, remote,
+				pretty_ref);
+		return 0;
+	}
+
+	if (current_branch &&
+	    !strcmp(ref->name, current_branch->name) &&
+	    !(update_head_ok || is_bare_repository()) &&
+	    !is_null_sha1(ref->old_sha1)) {
+		/*
+		 * If this is the head, and it's not okay to update
+		 * the head, and the old value of the head isn't empty...
+		 */
+		sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
+			TRANSPORT_SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
+			pretty_ref);
+		return 1;
+	}
+
+	if (!is_null_sha1(ref->old_sha1) &&
+	    !prefixcmp(ref->name, "refs/tags/")) {
+		int r;
+		r = s_update_ref("updating tag", ref, 0);
+		sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : '-',
+			TRANSPORT_SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
+			pretty_ref, r ? "  (unable to update local ref)" : "");
+		return r;
+	}
+
+	current = lookup_commit_reference_gently(ref->old_sha1, 1);
+	updated = lookup_commit_reference_gently(ref->new_sha1, 1);
+	if (!current || !updated) {
+		const char *msg;
+		const char *what;
+		int r;
+		if (!strncmp(ref->name, "refs/tags/", 10)) {
+			msg = "storing tag";
+			what = "[new tag]";
+		}
+		else {
+			msg = "storing head";
+			what = "[new branch]";
+		}
+
+		r = s_update_ref(msg, ref, 0);
+		sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : '*',
+			TRANSPORT_SUMMARY_WIDTH, what, REFCOL_WIDTH, remote, pretty_ref,
+			r ? "  (unable to update local ref)" : "");
+		return r;
+	}
+
+	if (in_merge_bases(current, &updated, 1)) {
+		char quickref[83];
+		int r;
+		strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
+		strcat(quickref, "..");
+		strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
+		r = s_update_ref("fast-forward", ref, 1);
+		sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : ' ',
+			TRANSPORT_SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote,
+			pretty_ref, r ? "  (unable to update local ref)" : "");
+		return r;
+	} else if (force || ref->force) {
+		char quickref[84];
+		int r;
+		strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
+		strcat(quickref, "...");
+		strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
+		r = s_update_ref("forced-update", ref, 1);
+		sprintf(display, "%c %-*s %-*s -> %s  (%s)", r ? '!' : '+',
+			TRANSPORT_SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote,
+			pretty_ref,
+			r ? "unable to update local ref" : "forced update");
+		return r;
+	} else {
+		sprintf(display, "! %-*s %-*s -> %s  (non-fast-forward)",
+			TRANSPORT_SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
+			pretty_ref);
+		return 1;
+	}
+}
+
+static int store_updated_refs(const char *raw_url, const char *remote_name,
+		struct ref *ref_map)
+{
+	FILE *fp;
+	struct commit *commit;
+	int url_len, i, note_len, shown_url = 0, rc = 0;
+	char note[1024];
+	const char *what, *kind;
+	struct ref *rm;
+	char *url, *filename = dry_run ? "/dev/null" : git_path("FETCH_HEAD");
+
+	fp = fopen(filename, "a");
+	if (!fp)
+		return error("cannot open %s: %s\n", filename, strerror(errno));
+
+	if (raw_url)
+		url = transport_anonymize_url(raw_url);
+	else
+		url = xstrdup("foreign");
+	for (rm = ref_map; rm; rm = rm->next) {
+		struct ref *ref = NULL;
+
+		if (rm->peer_ref) {
+			ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
+			strcpy(ref->name, rm->peer_ref->name);
+			hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
+			hashcpy(ref->new_sha1, rm->old_sha1);
+			ref->force = rm->peer_ref->force;
+		}
+
+		commit = lookup_commit_reference_gently(rm->old_sha1, 1);
+		if (!commit)
+			rm->merge = 0;
+
+		if (!strcmp(rm->name, "HEAD")) {
+			kind = "";
+			what = "";
+		}
+		else if (!prefixcmp(rm->name, "refs/heads/")) {
+			kind = "branch";
+			what = rm->name + 11;
+		}
+		else if (!prefixcmp(rm->name, "refs/tags/")) {
+			kind = "tag";
+			what = rm->name + 10;
+		}
+		else if (!prefixcmp(rm->name, "refs/remotes/")) {
+			kind = "remote branch";
+			what = rm->name + 13;
+		}
+		else {
+			kind = "";
+			what = rm->name;
+		}
+
+		url_len = strlen(url);
+		for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
+			;
+		url_len = i + 1;
+		if (4 < i && !strncmp(".git", url + i - 3, 4))
+			url_len = i - 3;
+
+		note_len = 0;
+		if (*what) {
+			if (*kind)
+				note_len += sprintf(note + note_len, "%s ",
+						    kind);
+			note_len += sprintf(note + note_len, "'%s' of ", what);
+		}
+		note[note_len] = '\0';
+		fprintf(fp, "%s\t%s\t%s",
+			sha1_to_hex(commit ? commit->object.sha1 :
+				    rm->old_sha1),
+			rm->merge ? "" : "not-for-merge",
+			note);
+		for (i = 0; i < url_len; ++i)
+			if ('\n' == url[i])
+				fputs("\\n", fp);
+			else
+				fputc(url[i], fp);
+		fputc('\n', fp);
+
+		if (ref)
+			rc |= update_local_ref(ref, what, note);
+		else
+			sprintf(note, "* %-*s %-*s -> FETCH_HEAD",
+				TRANSPORT_SUMMARY_WIDTH, *kind ? kind : "branch",
+				 REFCOL_WIDTH, *what ? what : "HEAD");
+		if (*note) {
+			if (verbosity >= 0 && !shown_url) {
+				fprintf(stderr, "From %.*s\n",
+						url_len, url);
+				shown_url = 1;
+			}
+			if (verbosity >= 0)
+				fprintf(stderr, " %s\n", note);
+		}
+	}
+	free(url);
+	fclose(fp);
+	if (rc & STORE_REF_ERROR_DF_CONFLICT)
+		error("some local refs could not be updated; try running\n"
+		      " 'git remote prune %s' to remove any old, conflicting "
+		      "branches", remote_name);
+	return rc;
+}
+
+/*
+ * We would want to bypass the object transfer altogether if
+ * everything we are going to fetch already exists and is connected
+ * locally.
+ *
+ * The refs we are going to fetch are in ref_map.  If running
+ *
+ *  $ git rev-list --objects --stdin --not --all
+ *
+ * (feeding all the refs in ref_map on its standard input)
+ * does not error out, that means everything reachable from the
+ * refs we are going to fetch exists and is connected to some of
+ * our existing refs.
+ */
+static int quickfetch(struct ref *ref_map)
+{
+	struct child_process revlist;
+	struct ref *ref;
+	int err;
+	const char *argv[] = {"rev-list",
+		"--quiet", "--objects", "--stdin", "--not", "--all", NULL};
+
+	/*
+	 * If we are deepening a shallow clone we already have these
+	 * objects reachable.  Running rev-list here will return with
+	 * a good (0) exit status and we'll bypass the fetch that we
+	 * really need to perform.  Claiming failure now will ensure
+	 * we perform the network exchange to deepen our history.
+	 */
+	if (depth)
+		return -1;
+
+	if (!ref_map)
+		return 0;
+
+	memset(&revlist, 0, sizeof(revlist));
+	revlist.argv = argv;
+	revlist.git_cmd = 1;
+	revlist.no_stdout = 1;
+	revlist.no_stderr = 1;
+	revlist.in = -1;
+
+	err = start_command(&revlist);
+	if (err) {
+		error("could not run rev-list");
+		return err;
+	}
+
+	/*
+	 * If rev-list --stdin encounters an unknown commit, it terminates,
+	 * which will cause SIGPIPE in the write loop below.
+	 */
+	sigchain_push(SIGPIPE, SIG_IGN);
+
+	for (ref = ref_map; ref; ref = ref->next) {
+		if (write_in_full(revlist.in, sha1_to_hex(ref->old_sha1), 40) < 0 ||
+		    write_str_in_full(revlist.in, "\n") < 0) {
+			if (errno != EPIPE && errno != EINVAL)
+				error("failed write to rev-list: %s", strerror(errno));
+			err = -1;
+			break;
+		}
+	}
+
+	if (close(revlist.in)) {
+		error("failed to close rev-list's stdin: %s", strerror(errno));
+		err = -1;
+	}
+
+	sigchain_pop(SIGPIPE);
+
+	return finish_command(&revlist) || err;
+}
+
+static int fetch_refs(struct transport *transport, struct ref *ref_map)
+{
+	int ret = quickfetch(ref_map);
+	if (ret)
+		ret = transport_fetch_refs(transport, ref_map);
+	if (!ret)
+		ret |= store_updated_refs(transport->url,
+				transport->remote->name,
+				ref_map);
+	transport_unlock_pack(transport);
+	return ret;
+}
+
+static int prune_refs(struct transport *transport, struct ref *ref_map)
+{
+	int result = 0;
+	struct ref *ref, *stale_refs = get_stale_heads(transport->remote, ref_map);
+	const char *dangling_msg = dry_run
+		? "   (%s will become dangling)\n"
+		: "   (%s has become dangling)\n";
+
+	for (ref = stale_refs; ref; ref = ref->next) {
+		if (!dry_run)
+			result |= delete_ref(ref->name, NULL, 0);
+		if (verbosity >= 0) {
+			fprintf(stderr, " x %-*s %-*s -> %s\n",
+				TRANSPORT_SUMMARY_WIDTH, "[deleted]",
+				REFCOL_WIDTH, "(none)", prettify_refname(ref->name));
+			warn_dangling_symref(stderr, dangling_msg, ref->name);
+		}
+	}
+	free_refs(stale_refs);
+	return result;
+}
+
+static int add_existing(const char *refname, const unsigned char *sha1,
+			int flag, void *cbdata)
+{
+	struct string_list *list = (struct string_list *)cbdata;
+	struct string_list_item *item = string_list_insert(refname, list);
+	item->util = (void *)sha1;
+	return 0;
+}
+
+static int will_fetch(struct ref **head, const unsigned char *sha1)
+{
+	struct ref *rm = *head;
+	while (rm) {
+		if (!hashcmp(rm->old_sha1, sha1))
+			return 1;
+		rm = rm->next;
+	}
+	return 0;
+}
+
+struct tag_data {
+	struct ref **head;
+	struct ref ***tail;
+};
+
+static int add_to_tail(struct string_list_item *item, void *cb_data)
+{
+	struct tag_data *data = (struct tag_data *)cb_data;
+	struct ref *rm = NULL;
+
+	/* We have already decided to ignore this item */
+	if (!item->util)
+		return 0;
+
+	rm = alloc_ref(item->string);
+	rm->peer_ref = alloc_ref(item->string);
+	hashcpy(rm->old_sha1, item->util);
+
+	**data->tail = rm;
+	*data->tail = &rm->next;
+
+	return 0;
+}
+
+static void find_non_local_tags(struct transport *transport,
+			struct ref **head,
+			struct ref ***tail)
+{
+	struct string_list existing_refs = { NULL, 0, 0, 0 };
+	struct string_list remote_refs = { NULL, 0, 0, 0 };
+	struct tag_data data = {head, tail};
+	const struct ref *ref;
+	struct string_list_item *item = NULL;
+
+	for_each_ref(add_existing, &existing_refs);
+	for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
+		if (prefixcmp(ref->name, "refs/tags"))
+			continue;
+
+		/*
+		 * The peeled ref always follows the matching base
+		 * ref, so if we see a peeled ref that we don't want
+		 * to fetch then we can mark the ref entry in the list
+		 * as one to ignore by setting util to NULL.
+		 */
+		if (!strcmp(ref->name + strlen(ref->name) - 3, "^{}")) {
+			if (item && !has_sha1_file(ref->old_sha1) &&
+			    !will_fetch(head, ref->old_sha1) &&
+			    !has_sha1_file(item->util) &&
+			    !will_fetch(head, item->util))
+				item->util = NULL;
+			item = NULL;
+			continue;
+		}
+
+		/*
+		 * If item is non-NULL here, then we previously saw a
+		 * ref not followed by a peeled reference, so we need
+		 * to check if it is a lightweight tag that we want to
+		 * fetch.
+		 */
+		if (item && !has_sha1_file(item->util) &&
+		    !will_fetch(head, item->util))
+			item->util = NULL;
+
+		item = NULL;
+
+		/* skip duplicates and refs that we already have */
+		if (string_list_has_string(&remote_refs, ref->name) ||
+		    string_list_has_string(&existing_refs, ref->name))
+			continue;
+
+		item = string_list_insert(ref->name, &remote_refs);
+		item->util = (void *)ref->old_sha1;
+	}
+	string_list_clear(&existing_refs, 0);
+
+	/*
+	 * We may have a final lightweight tag that needs to be
+	 * checked to see if it needs fetching.
+	 */
+	if (item && !has_sha1_file(item->util) &&
+	    !will_fetch(head, item->util))
+		item->util = NULL;
+
+	/*
+	 * For all the tags in the remote_refs string list, call
+	 * add_to_tail to add them to the list of refs to be fetched
+	 */
+	for_each_string_list(add_to_tail, &remote_refs, &data);
+
+	string_list_clear(&remote_refs, 0);
+}
+
+static void check_not_current_branch(struct ref *ref_map)
+{
+	struct branch *current_branch = branch_get(NULL);
+
+	if (is_bare_repository() || !current_branch)
+		return;
+
+	for (; ref_map; ref_map = ref_map->next)
+		if (ref_map->peer_ref && !strcmp(current_branch->refname,
+					ref_map->peer_ref->name))
+			die("Refusing to fetch into current branch %s "
+			    "of non-bare repository", current_branch->refname);
+}
+
+static int truncate_fetch_head(void)
+{
+	char *filename = git_path("FETCH_HEAD");
+	FILE *fp = fopen(filename, "w");
+
+	if (!fp)
+		return error("cannot open %s: %s\n", filename, strerror(errno));
+	fclose(fp);
+	return 0;
+}
+
+static int do_fetch(struct transport *transport,
+		    struct refspec *refs, int ref_count)
+{
+	struct string_list existing_refs = { NULL, 0, 0, 0 };
+	struct string_list_item *peer_item = NULL;
+	struct ref *ref_map;
+	struct ref *rm;
+	int autotags = (transport->remote->fetch_tags == 1);
+
+	for_each_ref(add_existing, &existing_refs);
+
+	if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
+		tags = TAGS_SET;
+	if (transport->remote->fetch_tags == -1)
+		tags = TAGS_UNSET;
+
+	if (!transport->get_refs_list || !transport->fetch)
+		die("Don't know how to fetch from %s", transport->url);
+
+	/* if not appending, truncate FETCH_HEAD */
+	if (!append && !dry_run) {
+		int errcode = truncate_fetch_head();
+		if (errcode)
+			return errcode;
+	}
+
+	ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
+	if (!update_head_ok)
+		check_not_current_branch(ref_map);
+
+	for (rm = ref_map; rm; rm = rm->next) {
+		if (rm->peer_ref) {
+			peer_item = string_list_lookup(rm->peer_ref->name,
+						       &existing_refs);
+			if (peer_item)
+				hashcpy(rm->peer_ref->old_sha1,
+					peer_item->util);
+		}
+	}
+
+	if (tags == TAGS_DEFAULT && autotags)
+		transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
+	if (fetch_refs(transport, ref_map)) {
+		free_refs(ref_map);
+		return 1;
+	}
+	if (prune)
+		prune_refs(transport, ref_map);
+	free_refs(ref_map);
+
+	/* if neither --no-tags nor --tags was specified, do automated tag
+	 * following ... */
+	if (tags == TAGS_DEFAULT && autotags) {
+		struct ref **tail = &ref_map;
+		ref_map = NULL;
+		find_non_local_tags(transport, &ref_map, &tail);
+		if (ref_map) {
+			transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
+			transport_set_option(transport, TRANS_OPT_DEPTH, "0");
+			fetch_refs(transport, ref_map);
+		}
+		free_refs(ref_map);
+	}
+
+	return 0;
+}
+
+static void set_option(const char *name, const char *value)
+{
+	int r = transport_set_option(transport, name, value);
+	if (r < 0)
+		die("Option \"%s\" value \"%s\" is not valid for %s",
+			name, value, transport->url);
+	if (r > 0)
+		warning("Option \"%s\" is ignored for %s\n",
+			name, transport->url);
+}
+
+static int get_one_remote_for_fetch(struct remote *remote, void *priv)
+{
+	struct string_list *list = priv;
+	if (!remote->skip_default_update)
+		string_list_append(remote->name, list);
+	return 0;
+}
+
+struct remote_group_data {
+	const char *name;
+	struct string_list *list;
+};
+
+static int get_remote_group(const char *key, const char *value, void *priv)
+{
+	struct remote_group_data *g = priv;
+
+	if (!prefixcmp(key, "remotes.") &&
+			!strcmp(key + 8, g->name)) {
+		/* split list by white space */
+		int space = strcspn(value, " \t\n");
+		while (*value) {
+			if (space > 1) {
+				string_list_append(xstrndup(value, space),
+						   g->list);
+			}
+			value += space + (value[space] != '\0');
+			space = strcspn(value, " \t\n");
+		}
+	}
+
+	return 0;
+}
+
+static int add_remote_or_group(const char *name, struct string_list *list)
+{
+	int prev_nr = list->nr;
+	struct remote_group_data g = { name, list };
+
+	git_config(get_remote_group, &g);
+	if (list->nr == prev_nr) {
+		struct remote *remote;
+		if (!remote_is_configured(name))
+			return 0;
+		remote = remote_get(name);
+		string_list_append(remote->name, list);
+	}
+	return 1;
+}
+
+static int fetch_multiple(struct string_list *list)
+{
+	int i, result = 0;
+	const char *argv[11] = { "fetch", "--append" };
+	int argc = 2;
+
+	if (dry_run)
+		argv[argc++] = "--dry-run";
+	if (prune)
+		argv[argc++] = "--prune";
+	if (update_head_ok)
+		argv[argc++] = "--update-head-ok";
+	if (force)
+		argv[argc++] = "--force";
+	if (keep)
+		argv[argc++] = "--keep";
+	if (verbosity >= 2)
+		argv[argc++] = "-v";
+	if (verbosity >= 1)
+		argv[argc++] = "-v";
+	else if (verbosity < 0)
+		argv[argc++] = "-q";
+
+	if (!append && !dry_run) {
+		int errcode = truncate_fetch_head();
+		if (errcode)
+			return errcode;
+	}
+
+	for (i = 0; i < list->nr; i++) {
+		const char *name = list->items[i].string;
+		argv[argc] = name;
+		argv[argc + 1] = NULL;
+		if (verbosity >= 0)
+			printf("Fetching %s\n", name);
+		if (run_command_v_opt(argv, RUN_GIT_CMD)) {
+			error("Could not fetch %s", name);
+			result = 1;
+		}
+	}
+
+	return result;
+}
+
+static int fetch_one(struct remote *remote, int argc, const char **argv)
+{
+	int i;
+	static const char **refs = NULL;
+	int ref_nr = 0;
+	int exit_code;
+
+	if (!remote)
+		die("Where do you want to fetch from today?");
+
+	transport = transport_get(remote, NULL);
+	if (verbosity >= 2)
+		transport->verbose = verbosity <= 3 ? verbosity : 3;
+	if (verbosity < 0)
+		transport->verbose = -1;
+	if (upload_pack)
+		set_option(TRANS_OPT_UPLOADPACK, upload_pack);
+	if (keep)
+		set_option(TRANS_OPT_KEEP, "yes");
+	if (depth)
+		set_option(TRANS_OPT_DEPTH, depth);
+
+	if (argc > 0) {
+		int j = 0;
+		refs = xcalloc(argc + 1, sizeof(const char *));
+		for (i = 0; i < argc; i++) {
+			if (!strcmp(argv[i], "tag")) {
+				char *ref;
+				i++;
+				if (i >= argc)
+					die("You need to specify a tag name.");
+				ref = xmalloc(strlen(argv[i]) * 2 + 22);
+				strcpy(ref, "refs/tags/");
+				strcat(ref, argv[i]);
+				strcat(ref, ":refs/tags/");
+				strcat(ref, argv[i]);
+				refs[j++] = ref;
+			} else
+				refs[j++] = argv[i];
+		}
+		refs[j] = NULL;
+		ref_nr = j;
+	}
+
+	sigchain_push_common(unlock_pack_on_signal);
+	atexit(unlock_pack);
+	exit_code = do_fetch(transport,
+			parse_fetch_refspec(ref_nr, refs), ref_nr);
+	transport_disconnect(transport);
+	transport = NULL;
+	return exit_code;
+}
+
+int cmd_fetch(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	struct string_list list = { NULL, 0, 0, 0 };
+	struct remote *remote;
+	int result = 0;
+
+	/* Record the command line for the reflog */
+	strbuf_addstr(&default_rla, "fetch");
+	for (i = 1; i < argc; i++)
+		strbuf_addf(&default_rla, " %s", argv[i]);
+
+	argc = parse_options(argc, argv, prefix,
+			     builtin_fetch_options, builtin_fetch_usage, 0);
+
+	if (all) {
+		if (argc == 1)
+			die("fetch --all does not take a repository argument");
+		else if (argc > 1)
+			die("fetch --all does not make sense with refspecs");
+		(void) for_each_remote(get_one_remote_for_fetch, &list);
+		result = fetch_multiple(&list);
+	} else if (argc == 0) {
+		/* No arguments -- use default remote */
+		remote = remote_get(NULL);
+		result = fetch_one(remote, argc, argv);
+	} else if (multiple) {
+		/* All arguments are assumed to be remotes or groups */
+		for (i = 0; i < argc; i++)
+			if (!add_remote_or_group(argv[i], &list))
+				die("No such remote or remote group: %s", argv[i]);
+		result = fetch_multiple(&list);
+	} else {
+		/* Single remote or group */
+		(void) add_remote_or_group(argv[0], &list);
+		if (list.nr > 1) {
+			/* More than one remote */
+			if (argc > 1)
+				die("Fetching a group and specifying refspecs does not make sense");
+			result = fetch_multiple(&list);
+		} else {
+			/* Zero or one remotes */
+			remote = remote_get(argv[0]);
+			result = fetch_one(remote, argc-1, argv+1);
+		}
+	}
+
+	/* All names were strdup()ed or strndup()ed */
+	list.strdup_strings = 1;
+	string_list_clear(&list, 0);
+
+	return result;
+}
diff --git a/builtin/fmt-merge-msg.c b/builtin/fmt-merge-msg.c
new file mode 100644
index 0000000..9d52400
--- /dev/null
+++ b/builtin/fmt-merge-msg.c
@@ -0,0 +1,381 @@
+#include "builtin.h"
+#include "cache.h"
+#include "commit.h"
+#include "diff.h"
+#include "revision.h"
+#include "tag.h"
+
+static const char * const fmt_merge_msg_usage[] = {
+	"git fmt-merge-msg [--log|--no-log] [--file <file>]",
+	NULL
+};
+
+static int merge_summary;
+
+static int fmt_merge_msg_config(const char *key, const char *value, void *cb)
+{
+	static int found_merge_log = 0;
+	if (!strcmp("merge.log", key)) {
+		found_merge_log = 1;
+		merge_summary = git_config_bool(key, value);
+	}
+	if (!found_merge_log && !strcmp("merge.summary", key))
+		merge_summary = git_config_bool(key, value);
+	return 0;
+}
+
+struct list {
+	char **list;
+	void **payload;
+	unsigned nr, alloc;
+};
+
+static void append_to_list(struct list *list, char *value, void *payload)
+{
+	if (list->nr == list->alloc) {
+		list->alloc += 32;
+		list->list = xrealloc(list->list, sizeof(char *) * list->alloc);
+		list->payload = xrealloc(list->payload,
+				sizeof(char *) * list->alloc);
+	}
+	list->payload[list->nr] = payload;
+	list->list[list->nr++] = value;
+}
+
+static int find_in_list(struct list *list, char *value)
+{
+	int i;
+
+	for (i = 0; i < list->nr; i++)
+		if (!strcmp(list->list[i], value))
+			return i;
+
+	return -1;
+}
+
+static void free_list(struct list *list)
+{
+	int i;
+
+	if (list->alloc == 0)
+		return;
+
+	for (i = 0; i < list->nr; i++) {
+		free(list->list[i]);
+		free(list->payload[i]);
+	}
+	free(list->list);
+	free(list->payload);
+	list->nr = list->alloc = 0;
+}
+
+struct src_data {
+	struct list branch, tag, r_branch, generic;
+	int head_status;
+};
+
+static struct list srcs = { NULL, NULL, 0, 0};
+static struct list origins = { NULL, NULL, 0, 0};
+
+static int handle_line(char *line)
+{
+	int i, len = strlen(line);
+	unsigned char *sha1;
+	char *src, *origin;
+	struct src_data *src_data;
+	int pulling_head = 0;
+
+	if (len < 43 || line[40] != '\t')
+		return 1;
+
+	if (!prefixcmp(line + 41, "not-for-merge"))
+		return 0;
+
+	if (line[41] != '\t')
+		return 2;
+
+	line[40] = 0;
+	sha1 = xmalloc(20);
+	i = get_sha1(line, sha1);
+	line[40] = '\t';
+	if (i)
+		return 3;
+
+	if (line[len - 1] == '\n')
+		line[len - 1] = 0;
+	line += 42;
+
+	src = strstr(line, " of ");
+	if (src) {
+		*src = 0;
+		src += 4;
+		pulling_head = 0;
+	} else {
+		src = line;
+		pulling_head = 1;
+	}
+
+	i = find_in_list(&srcs, src);
+	if (i < 0) {
+		i = srcs.nr;
+		append_to_list(&srcs, xstrdup(src),
+				xcalloc(1, sizeof(struct src_data)));
+	}
+	src_data = srcs.payload[i];
+
+	if (pulling_head) {
+		origin = xstrdup(src);
+		src_data->head_status |= 1;
+	} else if (!prefixcmp(line, "branch ")) {
+		origin = xstrdup(line + 7);
+		append_to_list(&src_data->branch, origin, NULL);
+		src_data->head_status |= 2;
+	} else if (!prefixcmp(line, "tag ")) {
+		origin = line;
+		append_to_list(&src_data->tag, xstrdup(origin + 4), NULL);
+		src_data->head_status |= 2;
+	} else if (!prefixcmp(line, "remote branch ")) {
+		origin = xstrdup(line + 14);
+		append_to_list(&src_data->r_branch, origin, NULL);
+		src_data->head_status |= 2;
+	} else {
+		origin = xstrdup(src);
+		append_to_list(&src_data->generic, xstrdup(line), NULL);
+		src_data->head_status |= 2;
+	}
+
+	if (!strcmp(".", src) || !strcmp(src, origin)) {
+		int len = strlen(origin);
+		if (origin[0] == '\'' && origin[len - 1] == '\'') {
+			origin = xmemdupz(origin + 1, len - 2);
+		} else {
+			origin = xstrdup(origin);
+		}
+	} else {
+		char *new_origin = xmalloc(strlen(origin) + strlen(src) + 5);
+		sprintf(new_origin, "%s of %s", origin, src);
+		origin = new_origin;
+	}
+	append_to_list(&origins, origin, sha1);
+	return 0;
+}
+
+static void print_joined(const char *singular, const char *plural,
+		struct list *list, struct strbuf *out)
+{
+	if (list->nr == 0)
+		return;
+	if (list->nr == 1) {
+		strbuf_addf(out, "%s%s", singular, list->list[0]);
+	} else {
+		int i;
+		strbuf_addstr(out, plural);
+		for (i = 0; i < list->nr - 1; i++)
+			strbuf_addf(out, "%s%s", i > 0 ? ", " : "", list->list[i]);
+		strbuf_addf(out, " and %s", list->list[list->nr - 1]);
+	}
+}
+
+static void shortlog(const char *name, unsigned char *sha1,
+		struct commit *head, struct rev_info *rev, int limit,
+		struct strbuf *out)
+{
+	int i, count = 0;
+	struct commit *commit;
+	struct object *branch;
+	struct list subjects = { NULL, NULL, 0, 0 };
+	int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
+
+	branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
+	if (!branch || branch->type != OBJ_COMMIT)
+		return;
+
+	setup_revisions(0, NULL, rev, NULL);
+	rev->ignore_merges = 1;
+	add_pending_object(rev, branch, name);
+	add_pending_object(rev, &head->object, "^HEAD");
+	head->object.flags |= UNINTERESTING;
+	if (prepare_revision_walk(rev))
+		die("revision walk setup failed");
+	while ((commit = get_revision(rev)) != NULL) {
+		char *oneline, *bol, *eol;
+
+		/* ignore merges */
+		if (commit->parents && commit->parents->next)
+			continue;
+
+		count++;
+		if (subjects.nr > limit)
+			continue;
+
+		bol = strstr(commit->buffer, "\n\n");
+		if (bol) {
+			unsigned char c;
+			do {
+				c = *++bol;
+			} while (isspace(c));
+			if (!c)
+				bol = NULL;
+		}
+
+		if (!bol) {
+			append_to_list(&subjects, xstrdup(sha1_to_hex(
+							commit->object.sha1)),
+					NULL);
+			continue;
+		}
+
+		eol = strchr(bol, '\n');
+		if (eol) {
+			oneline = xmemdupz(bol, eol - bol);
+		} else {
+			oneline = xstrdup(bol);
+		}
+		append_to_list(&subjects, oneline, NULL);
+	}
+
+	if (count > limit)
+		strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
+	else
+		strbuf_addf(out, "\n* %s:\n", name);
+
+	for (i = 0; i < subjects.nr; i++)
+		if (i >= limit)
+			strbuf_addf(out, "  ...\n");
+		else
+			strbuf_addf(out, "  %s\n", subjects.list[i]);
+
+	clear_commit_marks((struct commit *)branch, flags);
+	clear_commit_marks(head, flags);
+	free_commit_list(rev->commits);
+	rev->commits = NULL;
+	rev->pending.nr = 0;
+
+	free_list(&subjects);
+}
+
+int fmt_merge_msg(int merge_summary, struct strbuf *in, struct strbuf *out) {
+	int limit = 20, i = 0, pos = 0;
+	char *sep = "";
+	unsigned char head_sha1[20];
+	const char *current_branch;
+
+	/* get current branch */
+	current_branch = resolve_ref("HEAD", head_sha1, 1, NULL);
+	if (!current_branch)
+		die("No current branch");
+	if (!prefixcmp(current_branch, "refs/heads/"))
+		current_branch += 11;
+
+	/* get a line */
+	while (pos < in->len) {
+		int len;
+		char *newline, *p = in->buf + pos;
+
+		newline = strchr(p, '\n');
+		len = newline ? newline - p : strlen(p);
+		pos += len + !!newline;
+		i++;
+		p[len] = 0;
+		if (handle_line(p))
+			die ("Error in line %d: %.*s", i, len, p);
+	}
+
+	strbuf_addstr(out, "Merge ");
+	for (i = 0; i < srcs.nr; i++) {
+		struct src_data *src_data = srcs.payload[i];
+		const char *subsep = "";
+
+		strbuf_addstr(out, sep);
+		sep = "; ";
+
+		if (src_data->head_status == 1) {
+			strbuf_addstr(out, srcs.list[i]);
+			continue;
+		}
+		if (src_data->head_status == 3) {
+			subsep = ", ";
+			strbuf_addstr(out, "HEAD");
+		}
+		if (src_data->branch.nr) {
+			strbuf_addstr(out, subsep);
+			subsep = ", ";
+			print_joined("branch ", "branches ", &src_data->branch,
+					out);
+		}
+		if (src_data->r_branch.nr) {
+			strbuf_addstr(out, subsep);
+			subsep = ", ";
+			print_joined("remote branch ", "remote branches ",
+					&src_data->r_branch, out);
+		}
+		if (src_data->tag.nr) {
+			strbuf_addstr(out, subsep);
+			subsep = ", ";
+			print_joined("tag ", "tags ", &src_data->tag, out);
+		}
+		if (src_data->generic.nr) {
+			strbuf_addstr(out, subsep);
+			print_joined("commit ", "commits ", &src_data->generic,
+					out);
+		}
+		if (strcmp(".", srcs.list[i]))
+			strbuf_addf(out, " of %s", srcs.list[i]);
+	}
+
+	if (!strcmp("master", current_branch))
+		strbuf_addch(out, '\n');
+	else
+		strbuf_addf(out, " into %s\n", current_branch);
+
+	if (merge_summary) {
+		struct commit *head;
+		struct rev_info rev;
+
+		head = lookup_commit(head_sha1);
+		init_revisions(&rev, NULL);
+		rev.commit_format = CMIT_FMT_ONELINE;
+		rev.ignore_merges = 1;
+		rev.limited = 1;
+
+		for (i = 0; i < origins.nr; i++)
+			shortlog(origins.list[i], origins.payload[i],
+					head, &rev, limit, out);
+	}
+	return 0;
+}
+
+int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
+{
+	const char *inpath = NULL;
+	struct option options[] = {
+		OPT_BOOLEAN(0, "log",     &merge_summary, "populate log with the shortlog"),
+		OPT_BOOLEAN(0, "summary", &merge_summary, "alias for --log"),
+		OPT_FILENAME('F', "file", &inpath, "file to read from"),
+		OPT_END()
+	};
+
+	FILE *in = stdin;
+	struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
+	int ret;
+
+	git_config(fmt_merge_msg_config, NULL);
+	argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
+			     0);
+	if (argc > 0)
+		usage_with_options(fmt_merge_msg_usage, options);
+
+	if (inpath && strcmp(inpath, "-")) {
+		in = fopen(inpath, "r");
+		if (!in)
+			die_errno("cannot open '%s'", inpath);
+	}
+
+	if (strbuf_read(&input, fileno(in), 0) < 0)
+		die_errno("could not read input file");
+	ret = fmt_merge_msg(merge_summary, &input, &output);
+	if (ret)
+		return ret;
+	write_in_full(STDOUT_FILENO, output.buf, output.len);
+	return 0;
+}
diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
new file mode 100644
index 0000000..62be1bb
--- /dev/null
+++ b/builtin/for-each-ref.c
@@ -0,0 +1,996 @@
+#include "builtin.h"
+#include "cache.h"
+#include "refs.h"
+#include "object.h"
+#include "tag.h"
+#include "commit.h"
+#include "tree.h"
+#include "blob.h"
+#include "quote.h"
+#include "parse-options.h"
+#include "remote.h"
+
+/* Quoting styles */
+#define QUOTE_NONE 0
+#define QUOTE_SHELL 1
+#define QUOTE_PERL 2
+#define QUOTE_PYTHON 4
+#define QUOTE_TCL 8
+
+typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
+
+struct atom_value {
+	const char *s;
+	unsigned long ul; /* used for sorting when not FIELD_STR */
+};
+
+struct ref_sort {
+	struct ref_sort *next;
+	int atom; /* index into used_atom array */
+	unsigned reverse : 1;
+};
+
+struct refinfo {
+	char *refname;
+	unsigned char objectname[20];
+	int flag;
+	const char *symref;
+	struct atom_value *value;
+};
+
+static struct {
+	const char *name;
+	cmp_type cmp_type;
+} valid_atom[] = {
+	{ "refname" },
+	{ "objecttype" },
+	{ "objectsize", FIELD_ULONG },
+	{ "objectname" },
+	{ "tree" },
+	{ "parent" },
+	{ "numparent", FIELD_ULONG },
+	{ "object" },
+	{ "type" },
+	{ "tag" },
+	{ "author" },
+	{ "authorname" },
+	{ "authoremail" },
+	{ "authordate", FIELD_TIME },
+	{ "committer" },
+	{ "committername" },
+	{ "committeremail" },
+	{ "committerdate", FIELD_TIME },
+	{ "tagger" },
+	{ "taggername" },
+	{ "taggeremail" },
+	{ "taggerdate", FIELD_TIME },
+	{ "creator" },
+	{ "creatordate", FIELD_TIME },
+	{ "subject" },
+	{ "body" },
+	{ "contents" },
+	{ "upstream" },
+	{ "symref" },
+	{ "flag" },
+};
+
+/*
+ * An atom is a valid field atom listed above, possibly prefixed with
+ * a "*" to denote deref_tag().
+ *
+ * We parse given format string and sort specifiers, and make a list
+ * of properties that we need to extract out of objects.  refinfo
+ * structure will hold an array of values extracted that can be
+ * indexed with the "atom number", which is an index into this
+ * array.
+ */
+static const char **used_atom;
+static cmp_type *used_atom_type;
+static int used_atom_cnt, sort_atom_limit, need_tagged, need_symref;
+
+/*
+ * Used to parse format string and sort specifiers
+ */
+static int parse_atom(const char *atom, const char *ep)
+{
+	const char *sp;
+	int i, at;
+
+	sp = atom;
+	if (*sp == '*' && sp < ep)
+		sp++; /* deref */
+	if (ep <= sp)
+		die("malformed field name: %.*s", (int)(ep-atom), atom);
+
+	/* Do we have the atom already used elsewhere? */
+	for (i = 0; i < used_atom_cnt; i++) {
+		int len = strlen(used_atom[i]);
+		if (len == ep - atom && !memcmp(used_atom[i], atom, len))
+			return i;
+	}
+
+	/* Is the atom a valid one? */
+	for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
+		int len = strlen(valid_atom[i].name);
+		/*
+		 * If the atom name has a colon, strip it and everything after
+		 * it off - it specifies the format for this entry, and
+		 * shouldn't be used for checking against the valid_atom
+		 * table.
+		 */
+		const char *formatp = strchr(sp, ':');
+		if (!formatp || ep < formatp)
+			formatp = ep;
+		if (len == formatp - sp && !memcmp(valid_atom[i].name, sp, len))
+			break;
+	}
+
+	if (ARRAY_SIZE(valid_atom) <= i)
+		die("unknown field name: %.*s", (int)(ep-atom), atom);
+
+	/* Add it in, including the deref prefix */
+	at = used_atom_cnt;
+	used_atom_cnt++;
+	used_atom = xrealloc(used_atom,
+			     (sizeof *used_atom) * used_atom_cnt);
+	used_atom_type = xrealloc(used_atom_type,
+				  (sizeof(*used_atom_type) * used_atom_cnt));
+	used_atom[at] = xmemdupz(atom, ep - atom);
+	used_atom_type[at] = valid_atom[i].cmp_type;
+	if (*atom == '*')
+		need_tagged = 1;
+	if (!strcmp(used_atom[at], "symref"))
+		need_symref = 1;
+	return at;
+}
+
+/*
+ * In a format string, find the next occurrence of %(atom).
+ */
+static const char *find_next(const char *cp)
+{
+	while (*cp) {
+		if (*cp == '%') {
+			/*
+			 * %( is the start of an atom;
+			 * %% is a quoted per-cent.
+			 */
+			if (cp[1] == '(')
+				return cp;
+			else if (cp[1] == '%')
+				cp++; /* skip over two % */
+			/* otherwise this is a singleton, literal % */
+		}
+		cp++;
+	}
+	return NULL;
+}
+
+/*
+ * Make sure the format string is well formed, and parse out
+ * the used atoms.
+ */
+static int verify_format(const char *format)
+{
+	const char *cp, *sp;
+	for (cp = format; *cp && (sp = find_next(cp)); ) {
+		const char *ep = strchr(sp, ')');
+		if (!ep)
+			return error("malformed format string %s", sp);
+		/* sp points at "%(" and ep points at the closing ")" */
+		parse_atom(sp + 2, ep);
+		cp = ep + 1;
+	}
+	return 0;
+}
+
+/*
+ * Given an object name, read the object data and size, and return a
+ * "struct object".  If the object data we are returning is also borrowed
+ * by the "struct object" representation, set *eaten as well---it is a
+ * signal from parse_object_buffer to us not to free the buffer.
+ */
+static void *get_obj(const unsigned char *sha1, struct object **obj, unsigned long *sz, int *eaten)
+{
+	enum object_type type;
+	void *buf = read_sha1_file(sha1, &type, sz);
+
+	if (buf)
+		*obj = parse_object_buffer(sha1, type, *sz, buf, eaten);
+	else
+		*obj = NULL;
+	return buf;
+}
+
+/* See grab_values */
+static void grab_common_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
+{
+	int i;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &val[i];
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+		if (!strcmp(name, "objecttype"))
+			v->s = typename(obj->type);
+		else if (!strcmp(name, "objectsize")) {
+			char *s = xmalloc(40);
+			sprintf(s, "%lu", sz);
+			v->ul = sz;
+			v->s = s;
+		}
+		else if (!strcmp(name, "objectname")) {
+			char *s = xmalloc(41);
+			strcpy(s, sha1_to_hex(obj->sha1));
+			v->s = s;
+		}
+	}
+}
+
+/* See grab_values */
+static void grab_tag_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
+{
+	int i;
+	struct tag *tag = (struct tag *) obj;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &val[i];
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+		if (!strcmp(name, "tag"))
+			v->s = tag->tag;
+		else if (!strcmp(name, "type") && tag->tagged)
+			v->s = typename(tag->tagged->type);
+		else if (!strcmp(name, "object") && tag->tagged) {
+			char *s = xmalloc(41);
+			strcpy(s, sha1_to_hex(tag->tagged->sha1));
+			v->s = s;
+		}
+	}
+}
+
+static int num_parents(struct commit *commit)
+{
+	struct commit_list *parents;
+	int i;
+
+	for (i = 0, parents = commit->parents;
+	     parents;
+	     parents = parents->next)
+		i++;
+	return i;
+}
+
+/* See grab_values */
+static void grab_commit_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
+{
+	int i;
+	struct commit *commit = (struct commit *) obj;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &val[i];
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+		if (!strcmp(name, "tree")) {
+			char *s = xmalloc(41);
+			strcpy(s, sha1_to_hex(commit->tree->object.sha1));
+			v->s = s;
+		}
+		if (!strcmp(name, "numparent")) {
+			char *s = xmalloc(40);
+			v->ul = num_parents(commit);
+			sprintf(s, "%lu", v->ul);
+			v->s = s;
+		}
+		else if (!strcmp(name, "parent")) {
+			int num = num_parents(commit);
+			int i;
+			struct commit_list *parents;
+			char *s = xmalloc(41 * num + 1);
+			v->s = s;
+			for (i = 0, parents = commit->parents;
+			     parents;
+			     parents = parents->next, i = i + 41) {
+				struct commit *parent = parents->item;
+				strcpy(s+i, sha1_to_hex(parent->object.sha1));
+				if (parents->next)
+					s[i+40] = ' ';
+			}
+			if (!i)
+				*s = '\0';
+		}
+	}
+}
+
+static const char *find_wholine(const char *who, int wholen, const char *buf, unsigned long sz)
+{
+	const char *eol;
+	while (*buf) {
+		if (!strncmp(buf, who, wholen) &&
+		    buf[wholen] == ' ')
+			return buf + wholen + 1;
+		eol = strchr(buf, '\n');
+		if (!eol)
+			return "";
+		eol++;
+		if (*eol == '\n')
+			return ""; /* end of header */
+		buf = eol;
+	}
+	return "";
+}
+
+static const char *copy_line(const char *buf)
+{
+	const char *eol = strchrnul(buf, '\n');
+	return xmemdupz(buf, eol - buf);
+}
+
+static const char *copy_name(const char *buf)
+{
+	const char *cp;
+	for (cp = buf; *cp && *cp != '\n'; cp++) {
+		if (!strncmp(cp, " <", 2))
+			return xmemdupz(buf, cp - buf);
+	}
+	return "";
+}
+
+static const char *copy_email(const char *buf)
+{
+	const char *email = strchr(buf, '<');
+	const char *eoemail;
+	if (!email)
+		return "";
+	eoemail = strchr(email, '>');
+	if (!eoemail)
+		return "";
+	return xmemdupz(email, eoemail + 1 - email);
+}
+
+static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
+{
+	const char *eoemail = strstr(buf, "> ");
+	char *zone;
+	unsigned long timestamp;
+	long tz;
+	enum date_mode date_mode = DATE_NORMAL;
+	const char *formatp;
+
+	/*
+	 * We got here because atomname ends in "date" or "date<something>";
+	 * it's not possible that <something> is not ":<format>" because
+	 * parse_atom() wouldn't have allowed it, so we can assume that no
+	 * ":" means no format is specified, and use the default.
+	 */
+	formatp = strchr(atomname, ':');
+	if (formatp != NULL) {
+		formatp++;
+		date_mode = parse_date_format(formatp);
+	}
+
+	if (!eoemail)
+		goto bad;
+	timestamp = strtoul(eoemail + 2, &zone, 10);
+	if (timestamp == ULONG_MAX)
+		goto bad;
+	tz = strtol(zone, NULL, 10);
+	if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
+		goto bad;
+	v->s = xstrdup(show_date(timestamp, tz, date_mode));
+	v->ul = timestamp;
+	return;
+ bad:
+	v->s = "";
+	v->ul = 0;
+}
+
+/* See grab_values */
+static void grab_person(const char *who, struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
+{
+	int i;
+	int wholen = strlen(who);
+	const char *wholine = NULL;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &val[i];
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+		if (strncmp(who, name, wholen))
+			continue;
+		if (name[wholen] != 0 &&
+		    strcmp(name + wholen, "name") &&
+		    strcmp(name + wholen, "email") &&
+		    prefixcmp(name + wholen, "date"))
+			continue;
+		if (!wholine)
+			wholine = find_wholine(who, wholen, buf, sz);
+		if (!wholine)
+			return; /* no point looking for it */
+		if (name[wholen] == 0)
+			v->s = copy_line(wholine);
+		else if (!strcmp(name + wholen, "name"))
+			v->s = copy_name(wholine);
+		else if (!strcmp(name + wholen, "email"))
+			v->s = copy_email(wholine);
+		else if (!prefixcmp(name + wholen, "date"))
+			grab_date(wholine, v, name);
+	}
+
+	/*
+	 * For a tag or a commit object, if "creator" or "creatordate" is
+	 * requested, do something special.
+	 */
+	if (strcmp(who, "tagger") && strcmp(who, "committer"))
+		return; /* "author" for commit object is not wanted */
+	if (!wholine)
+		wholine = find_wholine(who, wholen, buf, sz);
+	if (!wholine)
+		return;
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &val[i];
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+
+		if (!prefixcmp(name, "creatordate"))
+			grab_date(wholine, v, name);
+		else if (!strcmp(name, "creator"))
+			v->s = copy_line(wholine);
+	}
+}
+
+static void find_subpos(const char *buf, unsigned long sz, const char **sub, const char **body)
+{
+	while (*buf) {
+		const char *eol = strchr(buf, '\n');
+		if (!eol)
+			return;
+		if (eol[1] == '\n') {
+			buf = eol + 1;
+			break; /* found end of header */
+		}
+		buf = eol + 1;
+	}
+	while (*buf == '\n')
+		buf++;
+	if (!*buf)
+		return;
+	*sub = buf; /* first non-empty line */
+	buf = strchr(buf, '\n');
+	if (!buf) {
+		*body = "";
+		return; /* no body */
+	}
+	while (*buf == '\n')
+		buf++; /* skip blank between subject and body */
+	*body = buf;
+}
+
+/* See grab_values */
+static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
+{
+	int i;
+	const char *subpos = NULL, *bodypos = NULL;
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &val[i];
+		if (!!deref != (*name == '*'))
+			continue;
+		if (deref)
+			name++;
+		if (strcmp(name, "subject") &&
+		    strcmp(name, "body") &&
+		    strcmp(name, "contents"))
+			continue;
+		if (!subpos)
+			find_subpos(buf, sz, &subpos, &bodypos);
+		if (!subpos)
+			return;
+
+		if (!strcmp(name, "subject"))
+			v->s = copy_line(subpos);
+		else if (!strcmp(name, "body"))
+			v->s = xstrdup(bodypos);
+		else if (!strcmp(name, "contents"))
+			v->s = xstrdup(subpos);
+	}
+}
+
+/*
+ * We want to have empty print-string for field requests
+ * that do not apply (e.g. "authordate" for a tag object)
+ */
+static void fill_missing_values(struct atom_value *val)
+{
+	int i;
+	for (i = 0; i < used_atom_cnt; i++) {
+		struct atom_value *v = &val[i];
+		if (v->s == NULL)
+			v->s = "";
+	}
+}
+
+/*
+ * val is a list of atom_value to hold returned values.  Extract
+ * the values for atoms in used_atom array out of (obj, buf, sz).
+ * when deref is false, (obj, buf, sz) is the object that is
+ * pointed at by the ref itself; otherwise it is the object the
+ * ref (which is a tag) refers to.
+ */
+static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
+{
+	grab_common_values(val, deref, obj, buf, sz);
+	switch (obj->type) {
+	case OBJ_TAG:
+		grab_tag_values(val, deref, obj, buf, sz);
+		grab_sub_body_contents(val, deref, obj, buf, sz);
+		grab_person("tagger", val, deref, obj, buf, sz);
+		break;
+	case OBJ_COMMIT:
+		grab_commit_values(val, deref, obj, buf, sz);
+		grab_sub_body_contents(val, deref, obj, buf, sz);
+		grab_person("author", val, deref, obj, buf, sz);
+		grab_person("committer", val, deref, obj, buf, sz);
+		break;
+	case OBJ_TREE:
+		// grab_tree_values(val, deref, obj, buf, sz);
+		break;
+	case OBJ_BLOB:
+		// grab_blob_values(val, deref, obj, buf, sz);
+		break;
+	default:
+		die("Eh?  Object of type %d?", obj->type);
+	}
+}
+
+static inline char *copy_advance(char *dst, const char *src)
+{
+	while (*src)
+		*dst++ = *src++;
+	return dst;
+}
+
+/*
+ * Parse the object referred by ref, and grab needed value.
+ */
+static void populate_value(struct refinfo *ref)
+{
+	void *buf;
+	struct object *obj;
+	int eaten, i;
+	unsigned long size;
+	const unsigned char *tagged;
+
+	ref->value = xcalloc(sizeof(struct atom_value), used_atom_cnt);
+
+	if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
+		unsigned char unused1[20];
+		const char *symref;
+		symref = resolve_ref(ref->refname, unused1, 1, NULL);
+		if (symref)
+			ref->symref = xstrdup(symref);
+		else
+			ref->symref = "";
+	}
+
+	/* Fill in specials first */
+	for (i = 0; i < used_atom_cnt; i++) {
+		const char *name = used_atom[i];
+		struct atom_value *v = &ref->value[i];
+		int deref = 0;
+		const char *refname;
+		const char *formatp;
+
+		if (*name == '*') {
+			deref = 1;
+			name++;
+		}
+
+		if (!prefixcmp(name, "refname"))
+			refname = ref->refname;
+		else if (!prefixcmp(name, "symref"))
+			refname = ref->symref ? ref->symref : "";
+		else if (!prefixcmp(name, "upstream")) {
+			struct branch *branch;
+			/* only local branches may have an upstream */
+			if (prefixcmp(ref->refname, "refs/heads/"))
+				continue;
+			branch = branch_get(ref->refname + 11);
+
+			if (!branch || !branch->merge || !branch->merge[0] ||
+			    !branch->merge[0]->dst)
+				continue;
+			refname = branch->merge[0]->dst;
+		}
+		else if (!strcmp(name, "flag")) {
+			char buf[256], *cp = buf;
+			if (ref->flag & REF_ISSYMREF)
+				cp = copy_advance(cp, ",symref");
+			if (ref->flag & REF_ISPACKED)
+				cp = copy_advance(cp, ",packed");
+			if (cp == buf)
+				v->s = "";
+			else {
+				*cp = '\0';
+				v->s = xstrdup(buf + 1);
+			}
+			continue;
+		}
+		else
+			continue;
+
+		formatp = strchr(name, ':');
+		/* look for "short" refname format */
+		if (formatp) {
+			formatp++;
+			if (!strcmp(formatp, "short"))
+				refname = shorten_unambiguous_ref(refname,
+						      warn_ambiguous_refs);
+			else
+				die("unknown %.*s format %s",
+				    (int)(formatp - name), name, formatp);
+		}
+
+		if (!deref)
+			v->s = refname;
+		else {
+			int len = strlen(refname);
+			char *s = xmalloc(len + 4);
+			sprintf(s, "%s^{}", refname);
+			v->s = s;
+		}
+	}
+
+	for (i = 0; i < used_atom_cnt; i++) {
+		struct atom_value *v = &ref->value[i];
+		if (v->s == NULL)
+			goto need_obj;
+	}
+	return;
+
+ need_obj:
+	buf = get_obj(ref->objectname, &obj, &size, &eaten);
+	if (!buf)
+		die("missing object %s for %s",
+		    sha1_to_hex(ref->objectname), ref->refname);
+	if (!obj)
+		die("parse_object_buffer failed on %s for %s",
+		    sha1_to_hex(ref->objectname), ref->refname);
+
+	grab_values(ref->value, 0, obj, buf, size);
+	if (!eaten)
+		free(buf);
+
+	/*
+	 * If there is no atom that wants to know about tagged
+	 * object, we are done.
+	 */
+	if (!need_tagged || (obj->type != OBJ_TAG))
+		return;
+
+	/*
+	 * If it is a tag object, see if we use a value that derefs
+	 * the object, and if we do grab the object it refers to.
+	 */
+	tagged = ((struct tag *)obj)->tagged->sha1;
+
+	/*
+	 * NEEDSWORK: This derefs tag only once, which
+	 * is good to deal with chains of trust, but
+	 * is not consistent with what deref_tag() does
+	 * which peels the onion to the core.
+	 */
+	buf = get_obj(tagged, &obj, &size, &eaten);
+	if (!buf)
+		die("missing object %s for %s",
+		    sha1_to_hex(tagged), ref->refname);
+	if (!obj)
+		die("parse_object_buffer failed on %s for %s",
+		    sha1_to_hex(tagged), ref->refname);
+	grab_values(ref->value, 1, obj, buf, size);
+	if (!eaten)
+		free(buf);
+}
+
+/*
+ * Given a ref, return the value for the atom.  This lazily gets value
+ * out of the object by calling populate value.
+ */
+static void get_value(struct refinfo *ref, int atom, struct atom_value **v)
+{
+	if (!ref->value) {
+		populate_value(ref);
+		fill_missing_values(ref->value);
+	}
+	*v = &ref->value[atom];
+}
+
+struct grab_ref_cbdata {
+	struct refinfo **grab_array;
+	const char **grab_pattern;
+	int grab_cnt;
+};
+
+/*
+ * A call-back given to for_each_ref().  Filter refs and keep them for
+ * later object processing.
+ */
+static int grab_single_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	struct grab_ref_cbdata *cb = cb_data;
+	struct refinfo *ref;
+	int cnt;
+
+	if (*cb->grab_pattern) {
+		const char **pattern;
+		int namelen = strlen(refname);
+		for (pattern = cb->grab_pattern; *pattern; pattern++) {
+			const char *p = *pattern;
+			int plen = strlen(p);
+
+			if ((plen <= namelen) &&
+			    !strncmp(refname, p, plen) &&
+			    (refname[plen] == '\0' ||
+			     refname[plen] == '/' ||
+			     p[plen-1] == '/'))
+				break;
+			if (!fnmatch(p, refname, FNM_PATHNAME))
+				break;
+		}
+		if (!*pattern)
+			return 0;
+	}
+
+	/*
+	 * We do not open the object yet; sort may only need refname
+	 * to do its job and the resulting list may yet to be pruned
+	 * by maxcount logic.
+	 */
+	ref = xcalloc(1, sizeof(*ref));
+	ref->refname = xstrdup(refname);
+	hashcpy(ref->objectname, sha1);
+	ref->flag = flag;
+
+	cnt = cb->grab_cnt;
+	cb->grab_array = xrealloc(cb->grab_array,
+				  sizeof(*cb->grab_array) * (cnt + 1));
+	cb->grab_array[cnt++] = ref;
+	cb->grab_cnt = cnt;
+	return 0;
+}
+
+static int cmp_ref_sort(struct ref_sort *s, struct refinfo *a, struct refinfo *b)
+{
+	struct atom_value *va, *vb;
+	int cmp;
+	cmp_type cmp_type = used_atom_type[s->atom];
+
+	get_value(a, s->atom, &va);
+	get_value(b, s->atom, &vb);
+	switch (cmp_type) {
+	case FIELD_STR:
+		cmp = strcmp(va->s, vb->s);
+		break;
+	default:
+		if (va->ul < vb->ul)
+			cmp = -1;
+		else if (va->ul == vb->ul)
+			cmp = 0;
+		else
+			cmp = 1;
+		break;
+	}
+	return (s->reverse) ? -cmp : cmp;
+}
+
+static struct ref_sort *ref_sort;
+static int compare_refs(const void *a_, const void *b_)
+{
+	struct refinfo *a = *((struct refinfo **)a_);
+	struct refinfo *b = *((struct refinfo **)b_);
+	struct ref_sort *s;
+
+	for (s = ref_sort; s; s = s->next) {
+		int cmp = cmp_ref_sort(s, a, b);
+		if (cmp)
+			return cmp;
+	}
+	return 0;
+}
+
+static void sort_refs(struct ref_sort *sort, struct refinfo **refs, int num_refs)
+{
+	ref_sort = sort;
+	qsort(refs, num_refs, sizeof(struct refinfo *), compare_refs);
+}
+
+static void print_value(struct refinfo *ref, int atom, int quote_style)
+{
+	struct atom_value *v;
+	get_value(ref, atom, &v);
+	switch (quote_style) {
+	case QUOTE_NONE:
+		fputs(v->s, stdout);
+		break;
+	case QUOTE_SHELL:
+		sq_quote_print(stdout, v->s);
+		break;
+	case QUOTE_PERL:
+		perl_quote_print(stdout, v->s);
+		break;
+	case QUOTE_PYTHON:
+		python_quote_print(stdout, v->s);
+		break;
+	case QUOTE_TCL:
+		tcl_quote_print(stdout, v->s);
+		break;
+	}
+}
+
+static int hex1(char ch)
+{
+	if ('0' <= ch && ch <= '9')
+		return ch - '0';
+	else if ('a' <= ch && ch <= 'f')
+		return ch - 'a' + 10;
+	else if ('A' <= ch && ch <= 'F')
+		return ch - 'A' + 10;
+	return -1;
+}
+static int hex2(const char *cp)
+{
+	if (cp[0] && cp[1])
+		return (hex1(cp[0]) << 4) | hex1(cp[1]);
+	else
+		return -1;
+}
+
+static void emit(const char *cp, const char *ep)
+{
+	while (*cp && (!ep || cp < ep)) {
+		if (*cp == '%') {
+			if (cp[1] == '%')
+				cp++;
+			else {
+				int ch = hex2(cp + 1);
+				if (0 <= ch) {
+					putchar(ch);
+					cp += 3;
+					continue;
+				}
+			}
+		}
+		putchar(*cp);
+		cp++;
+	}
+}
+
+static void show_ref(struct refinfo *info, const char *format, int quote_style)
+{
+	const char *cp, *sp, *ep;
+
+	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
+		ep = strchr(sp, ')');
+		if (cp < sp)
+			emit(cp, sp);
+		print_value(info, parse_atom(sp + 2, ep), quote_style);
+	}
+	if (*cp) {
+		sp = cp + strlen(cp);
+		emit(cp, sp);
+	}
+	putchar('\n');
+}
+
+static struct ref_sort *default_sort(void)
+{
+	static const char cstr_name[] = "refname";
+
+	struct ref_sort *sort = xcalloc(1, sizeof(*sort));
+
+	sort->next = NULL;
+	sort->atom = parse_atom(cstr_name, cstr_name + strlen(cstr_name));
+	return sort;
+}
+
+static int opt_parse_sort(const struct option *opt, const char *arg, int unset)
+{
+	struct ref_sort **sort_tail = opt->value;
+	struct ref_sort *s;
+	int len;
+
+	if (!arg) /* should --no-sort void the list ? */
+		return -1;
+
+	*sort_tail = s = xcalloc(1, sizeof(*s));
+
+	if (*arg == '-') {
+		s->reverse = 1;
+		arg++;
+	}
+	len = strlen(arg);
+	s->atom = parse_atom(arg, arg+len);
+	return 0;
+}
+
+static char const * const for_each_ref_usage[] = {
+	"git for-each-ref [options] [<pattern>]",
+	NULL
+};
+
+int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
+{
+	int i, num_refs;
+	const char *format = "%(objectname) %(objecttype)\t%(refname)";
+	struct ref_sort *sort = NULL, **sort_tail = &sort;
+	int maxcount = 0, quote_style = 0;
+	struct refinfo **refs;
+	struct grab_ref_cbdata cbdata;
+
+	struct option opts[] = {
+		OPT_BIT('s', "shell", &quote_style,
+		        "quote placeholders suitably for shells", QUOTE_SHELL),
+		OPT_BIT('p', "perl",  &quote_style,
+		        "quote placeholders suitably for perl", QUOTE_PERL),
+		OPT_BIT(0 , "python", &quote_style,
+		        "quote placeholders suitably for python", QUOTE_PYTHON),
+		OPT_BIT(0 , "tcl",  &quote_style,
+		        "quote placeholders suitably for tcl", QUOTE_TCL),
+
+		OPT_GROUP(""),
+		OPT_INTEGER( 0 , "count", &maxcount, "show only <n> matched refs"),
+		OPT_STRING(  0 , "format", &format, "format", "format to use for the output"),
+		OPT_CALLBACK(0 , "sort", sort_tail, "key",
+		            "field name to sort on", &opt_parse_sort),
+		OPT_END(),
+	};
+
+	parse_options(argc, argv, prefix, opts, for_each_ref_usage, 0);
+	if (maxcount < 0) {
+		error("invalid --count argument: `%d'", maxcount);
+		usage_with_options(for_each_ref_usage, opts);
+	}
+	if (HAS_MULTI_BITS(quote_style)) {
+		error("more than one quoting style?");
+		usage_with_options(for_each_ref_usage, opts);
+	}
+	if (verify_format(format))
+		usage_with_options(for_each_ref_usage, opts);
+
+	if (!sort)
+		sort = default_sort();
+	sort_atom_limit = used_atom_cnt;
+
+	/* for warn_ambiguous_refs */
+	git_config(git_default_config, NULL);
+
+	memset(&cbdata, 0, sizeof(cbdata));
+	cbdata.grab_pattern = argv;
+	for_each_rawref(grab_single_ref, &cbdata);
+	refs = cbdata.grab_array;
+	num_refs = cbdata.grab_cnt;
+
+	sort_refs(sort, refs, num_refs);
+
+	if (!maxcount || num_refs < maxcount)
+		maxcount = num_refs;
+	for (i = 0; i < maxcount; i++)
+		show_ref(refs[i], format, quote_style);
+	return 0;
+}
diff --git a/builtin/fsck.c b/builtin/fsck.c
new file mode 100644
index 0000000..0929c7f
--- /dev/null
+++ b/builtin/fsck.c
@@ -0,0 +1,684 @@
+#include "builtin.h"
+#include "cache.h"
+#include "commit.h"
+#include "tree.h"
+#include "blob.h"
+#include "tag.h"
+#include "refs.h"
+#include "pack.h"
+#include "cache-tree.h"
+#include "tree-walk.h"
+#include "fsck.h"
+#include "parse-options.h"
+#include "dir.h"
+
+#define REACHABLE 0x0001
+#define SEEN      0x0002
+
+static int show_root;
+static int show_tags;
+static int show_unreachable;
+static int include_reflogs = 1;
+static int check_full = 1;
+static int check_strict;
+static int keep_cache_objects;
+static unsigned char head_sha1[20];
+static const char *head_points_at;
+static int errors_found;
+static int write_lost_and_found;
+static int verbose;
+#define ERROR_OBJECT 01
+#define ERROR_REACHABLE 02
+
+#ifdef NO_D_INO_IN_DIRENT
+#define SORT_DIRENT 0
+#define DIRENT_SORT_HINT(de) 0
+#else
+#define SORT_DIRENT 1
+#define DIRENT_SORT_HINT(de) ((de)->d_ino)
+#endif
+
+static void objreport(struct object *obj, const char *severity,
+                      const char *err, va_list params)
+{
+	fprintf(stderr, "%s in %s %s: ",
+	        severity, typename(obj->type), sha1_to_hex(obj->sha1));
+	vfprintf(stderr, err, params);
+	fputs("\n", stderr);
+}
+
+__attribute__((format (printf, 2, 3)))
+static int objerror(struct object *obj, const char *err, ...)
+{
+	va_list params;
+	va_start(params, err);
+	errors_found |= ERROR_OBJECT;
+	objreport(obj, "error", err, params);
+	va_end(params);
+	return -1;
+}
+
+__attribute__((format (printf, 3, 4)))
+static int fsck_error_func(struct object *obj, int type, const char *err, ...)
+{
+	va_list params;
+	va_start(params, err);
+	objreport(obj, (type == FSCK_WARN) ? "warning" : "error", err, params);
+	va_end(params);
+	return (type == FSCK_WARN) ? 0 : 1;
+}
+
+static struct object_array pending;
+
+static int mark_object(struct object *obj, int type, void *data)
+{
+	struct object *parent = data;
+
+	if (!obj) {
+		printf("broken link from %7s %s\n",
+			   typename(parent->type), sha1_to_hex(parent->sha1));
+		printf("broken link from %7s %s\n",
+			   (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
+		errors_found |= ERROR_REACHABLE;
+		return 1;
+	}
+
+	if (type != OBJ_ANY && obj->type != type)
+		objerror(parent, "wrong object type in link");
+
+	if (obj->flags & REACHABLE)
+		return 0;
+	obj->flags |= REACHABLE;
+	if (!obj->parsed) {
+		if (parent && !has_sha1_file(obj->sha1)) {
+			printf("broken link from %7s %s\n",
+				 typename(parent->type), sha1_to_hex(parent->sha1));
+			printf("              to %7s %s\n",
+				 typename(obj->type), sha1_to_hex(obj->sha1));
+			errors_found |= ERROR_REACHABLE;
+		}
+		return 1;
+	}
+
+	add_object_array(obj, (void *) parent, &pending);
+	return 0;
+}
+
+static void mark_object_reachable(struct object *obj)
+{
+	mark_object(obj, OBJ_ANY, NULL);
+}
+
+static int traverse_one_object(struct object *obj, struct object *parent)
+{
+	int result;
+	struct tree *tree = NULL;
+
+	if (obj->type == OBJ_TREE) {
+		obj->parsed = 0;
+		tree = (struct tree *)obj;
+		if (parse_tree(tree) < 0)
+			return 1; /* error already displayed */
+	}
+	result = fsck_walk(obj, mark_object, obj);
+	if (tree) {
+		free(tree->buffer);
+		tree->buffer = NULL;
+	}
+	return result;
+}
+
+static int traverse_reachable(void)
+{
+	int result = 0;
+	while (pending.nr) {
+		struct object_array_entry *entry;
+		struct object *obj, *parent;
+
+		entry = pending.objects + --pending.nr;
+		obj = entry->item;
+		parent = (struct object *) entry->name;
+		result |= traverse_one_object(obj, parent);
+	}
+	return !!result;
+}
+
+static int mark_used(struct object *obj, int type, void *data)
+{
+	if (!obj)
+		return 1;
+	obj->used = 1;
+	return 0;
+}
+
+/*
+ * Check a single reachable object
+ */
+static void check_reachable_object(struct object *obj)
+{
+	/*
+	 * We obviously want the object to be parsed,
+	 * except if it was in a pack-file and we didn't
+	 * do a full fsck
+	 */
+	if (!obj->parsed) {
+		if (has_sha1_pack(obj->sha1))
+			return; /* it is in pack - forget about it */
+		printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
+		errors_found |= ERROR_REACHABLE;
+		return;
+	}
+}
+
+/*
+ * Check a single unreachable object
+ */
+static void check_unreachable_object(struct object *obj)
+{
+	/*
+	 * Missing unreachable object? Ignore it. It's not like
+	 * we miss it (since it can't be reached), nor do we want
+	 * to complain about it being unreachable (since it does
+	 * not exist).
+	 */
+	if (!obj->parsed)
+		return;
+
+	/*
+	 * Unreachable object that exists? Show it if asked to,
+	 * since this is something that is prunable.
+	 */
+	if (show_unreachable) {
+		printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
+		return;
+	}
+
+	/*
+	 * "!used" means that nothing at all points to it, including
+	 * other unreachable objects. In other words, it's the "tip"
+	 * of some set of unreachable objects, usually a commit that
+	 * got dropped.
+	 *
+	 * Such starting points are more interesting than some random
+	 * set of unreachable objects, so we show them even if the user
+	 * hasn't asked for _all_ unreachable objects. If you have
+	 * deleted a branch by mistake, this is a prime candidate to
+	 * start looking at, for example.
+	 */
+	if (!obj->used) {
+		printf("dangling %s %s\n", typename(obj->type),
+		       sha1_to_hex(obj->sha1));
+		if (write_lost_and_found) {
+			char *filename = git_path("lost-found/%s/%s",
+				obj->type == OBJ_COMMIT ? "commit" : "other",
+				sha1_to_hex(obj->sha1));
+			FILE *f;
+
+			if (safe_create_leading_directories(filename)) {
+				error("Could not create lost-found");
+				return;
+			}
+			if (!(f = fopen(filename, "w")))
+				die_errno("Could not open '%s'", filename);
+			if (obj->type == OBJ_BLOB) {
+				enum object_type type;
+				unsigned long size;
+				char *buf = read_sha1_file(obj->sha1,
+						&type, &size);
+				if (buf) {
+					if (fwrite(buf, size, 1, f) != 1)
+						die_errno("Could not write '%s'",
+							  filename);
+					free(buf);
+				}
+			} else
+				fprintf(f, "%s\n", sha1_to_hex(obj->sha1));
+			if (fclose(f))
+				die_errno("Could not finish '%s'",
+					  filename);
+		}
+		return;
+	}
+
+	/*
+	 * Otherwise? It's there, it's unreachable, and some other unreachable
+	 * object points to it. Ignore it - it's not interesting, and we showed
+	 * all the interesting cases above.
+	 */
+}
+
+static void check_object(struct object *obj)
+{
+	if (verbose)
+		fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1));
+
+	if (obj->flags & REACHABLE)
+		check_reachable_object(obj);
+	else
+		check_unreachable_object(obj);
+}
+
+static void check_connectivity(void)
+{
+	int i, max;
+
+	/* Traverse the pending reachable objects */
+	traverse_reachable();
+
+	/* Look up all the requirements, warn about missing objects.. */
+	max = get_max_object_index();
+	if (verbose)
+		fprintf(stderr, "Checking connectivity (%d objects)\n", max);
+
+	for (i = 0; i < max; i++) {
+		struct object *obj = get_indexed_object(i);
+
+		if (obj)
+			check_object(obj);
+	}
+}
+
+static int fsck_sha1(const unsigned char *sha1)
+{
+	struct object *obj = parse_object(sha1);
+	if (!obj) {
+		errors_found |= ERROR_OBJECT;
+		return error("%s: object corrupt or missing",
+			     sha1_to_hex(sha1));
+	}
+	if (obj->flags & SEEN)
+		return 0;
+	obj->flags |= SEEN;
+
+	if (verbose)
+		fprintf(stderr, "Checking %s %s\n",
+			typename(obj->type), sha1_to_hex(obj->sha1));
+
+	if (fsck_walk(obj, mark_used, NULL))
+		objerror(obj, "broken links");
+	if (fsck_object(obj, check_strict, fsck_error_func))
+		return -1;
+
+	if (obj->type == OBJ_TREE) {
+		struct tree *item = (struct tree *) obj;
+
+		free(item->buffer);
+		item->buffer = NULL;
+	}
+
+	if (obj->type == OBJ_COMMIT) {
+		struct commit *commit = (struct commit *) obj;
+
+		free(commit->buffer);
+		commit->buffer = NULL;
+
+		if (!commit->parents && show_root)
+			printf("root %s\n", sha1_to_hex(commit->object.sha1));
+	}
+
+	if (obj->type == OBJ_TAG) {
+		struct tag *tag = (struct tag *) obj;
+
+		if (show_tags && tag->tagged) {
+			printf("tagged %s %s", typename(tag->tagged->type), sha1_to_hex(tag->tagged->sha1));
+			printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * This is the sorting chunk size: make it reasonably
+ * big so that we can sort well..
+ */
+#define MAX_SHA1_ENTRIES (1024)
+
+struct sha1_entry {
+	unsigned long ino;
+	unsigned char sha1[20];
+};
+
+static struct {
+	unsigned long nr;
+	struct sha1_entry *entry[MAX_SHA1_ENTRIES];
+} sha1_list;
+
+static int ino_compare(const void *_a, const void *_b)
+{
+	const struct sha1_entry *a = _a, *b = _b;
+	unsigned long ino1 = a->ino, ino2 = b->ino;
+	return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
+}
+
+static void fsck_sha1_list(void)
+{
+	int i, nr = sha1_list.nr;
+
+	if (SORT_DIRENT)
+		qsort(sha1_list.entry, nr,
+		      sizeof(struct sha1_entry *), ino_compare);
+	for (i = 0; i < nr; i++) {
+		struct sha1_entry *entry = sha1_list.entry[i];
+		unsigned char *sha1 = entry->sha1;
+
+		sha1_list.entry[i] = NULL;
+		fsck_sha1(sha1);
+		free(entry);
+	}
+	sha1_list.nr = 0;
+}
+
+static void add_sha1_list(unsigned char *sha1, unsigned long ino)
+{
+	struct sha1_entry *entry = xmalloc(sizeof(*entry));
+	int nr;
+
+	entry->ino = ino;
+	hashcpy(entry->sha1, sha1);
+	nr = sha1_list.nr;
+	if (nr == MAX_SHA1_ENTRIES) {
+		fsck_sha1_list();
+		nr = 0;
+	}
+	sha1_list.entry[nr] = entry;
+	sha1_list.nr = ++nr;
+}
+
+static void fsck_dir(int i, char *path)
+{
+	DIR *dir = opendir(path);
+	struct dirent *de;
+
+	if (!dir)
+		return;
+
+	if (verbose)
+		fprintf(stderr, "Checking directory %s\n", path);
+
+	while ((de = readdir(dir)) != NULL) {
+		char name[100];
+		unsigned char sha1[20];
+
+		if (is_dot_or_dotdot(de->d_name))
+			continue;
+		if (strlen(de->d_name) == 38) {
+			sprintf(name, "%02x", i);
+			memcpy(name+2, de->d_name, 39);
+			if (get_sha1_hex(name, sha1) < 0)
+				break;
+			add_sha1_list(sha1, DIRENT_SORT_HINT(de));
+			continue;
+		}
+		if (!prefixcmp(de->d_name, "tmp_obj_"))
+			continue;
+		fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
+	}
+	closedir(dir);
+}
+
+static int default_refs;
+
+static int fsck_handle_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
+		const char *email, unsigned long timestamp, int tz,
+		const char *message, void *cb_data)
+{
+	struct object *obj;
+
+	if (verbose)
+		fprintf(stderr, "Checking reflog %s->%s\n",
+			sha1_to_hex(osha1), sha1_to_hex(nsha1));
+
+	if (!is_null_sha1(osha1)) {
+		obj = lookup_object(osha1);
+		if (obj) {
+			obj->used = 1;
+			mark_object_reachable(obj);
+		}
+	}
+	obj = lookup_object(nsha1);
+	if (obj) {
+		obj->used = 1;
+		mark_object_reachable(obj);
+	}
+	return 0;
+}
+
+static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	for_each_reflog_ent(logname, fsck_handle_reflog_ent, NULL);
+	return 0;
+}
+
+static int is_branch(const char *refname)
+{
+	return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
+}
+
+static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	struct object *obj;
+
+	obj = parse_object(sha1);
+	if (!obj) {
+		error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
+		/* We'll continue with the rest despite the error.. */
+		return 0;
+	}
+	if (obj->type != OBJ_COMMIT && is_branch(refname))
+		error("%s: not a commit", refname);
+	default_refs++;
+	obj->used = 1;
+	mark_object_reachable(obj);
+
+	return 0;
+}
+
+static void get_default_heads(void)
+{
+	if (head_points_at && !is_null_sha1(head_sha1))
+		fsck_handle_ref("HEAD", head_sha1, 0, NULL);
+	for_each_ref(fsck_handle_ref, NULL);
+	if (include_reflogs)
+		for_each_reflog(fsck_handle_reflog, NULL);
+
+	/*
+	 * Not having any default heads isn't really fatal, but
+	 * it does mean that "--unreachable" no longer makes any
+	 * sense (since in this case everything will obviously
+	 * be unreachable by definition.
+	 *
+	 * Showing dangling objects is valid, though (as those
+	 * dangling objects are likely lost heads).
+	 *
+	 * So we just print a warning about it, and clear the
+	 * "show_unreachable" flag.
+	 */
+	if (!default_refs) {
+		fprintf(stderr, "notice: No default references\n");
+		show_unreachable = 0;
+	}
+}
+
+static void fsck_object_dir(const char *path)
+{
+	int i;
+
+	if (verbose)
+		fprintf(stderr, "Checking object directory\n");
+
+	for (i = 0; i < 256; i++) {
+		static char dir[4096];
+		sprintf(dir, "%s/%02x", path, i);
+		fsck_dir(i, dir);
+	}
+	fsck_sha1_list();
+}
+
+static int fsck_head_link(void)
+{
+	int flag;
+	int null_is_error = 0;
+
+	if (verbose)
+		fprintf(stderr, "Checking HEAD link\n");
+
+	head_points_at = resolve_ref("HEAD", head_sha1, 0, &flag);
+	if (!head_points_at)
+		return error("Invalid HEAD");
+	if (!strcmp(head_points_at, "HEAD"))
+		/* detached HEAD */
+		null_is_error = 1;
+	else if (prefixcmp(head_points_at, "refs/heads/"))
+		return error("HEAD points to something strange (%s)",
+			     head_points_at);
+	if (is_null_sha1(head_sha1)) {
+		if (null_is_error)
+			return error("HEAD: detached HEAD points at nothing");
+		fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
+			head_points_at + 11);
+	}
+	return 0;
+}
+
+static int fsck_cache_tree(struct cache_tree *it)
+{
+	int i;
+	int err = 0;
+
+	if (verbose)
+		fprintf(stderr, "Checking cache tree\n");
+
+	if (0 <= it->entry_count) {
+		struct object *obj = parse_object(it->sha1);
+		if (!obj) {
+			error("%s: invalid sha1 pointer in cache-tree",
+			      sha1_to_hex(it->sha1));
+			return 1;
+		}
+		mark_object_reachable(obj);
+		obj->used = 1;
+		if (obj->type != OBJ_TREE)
+			err |= objerror(obj, "non-tree in cache-tree");
+	}
+	for (i = 0; i < it->subtree_nr; i++)
+		err |= fsck_cache_tree(it->down[i]->cache_tree);
+	return err;
+}
+
+static char const * const fsck_usage[] = {
+	"git fsck [options] [<object>...]",
+	NULL
+};
+
+static struct option fsck_opts[] = {
+	OPT__VERBOSE(&verbose),
+	OPT_BOOLEAN(0, "unreachable", &show_unreachable, "show unreachable objects"),
+	OPT_BOOLEAN(0, "tags", &show_tags, "report tags"),
+	OPT_BOOLEAN(0, "root", &show_root, "report root nodes"),
+	OPT_BOOLEAN(0, "cache", &keep_cache_objects, "make index objects head nodes"),
+	OPT_BOOLEAN(0, "reflogs", &include_reflogs, "make reflogs head nodes (default)"),
+	OPT_BOOLEAN(0, "full", &check_full, "also consider packs and alternate objects"),
+	OPT_BOOLEAN(0, "strict", &check_strict, "enable more strict checking"),
+	OPT_BOOLEAN(0, "lost-found", &write_lost_and_found,
+				"write dangling objects in .git/lost-found"),
+	OPT_END(),
+};
+
+int cmd_fsck(int argc, const char **argv, const char *prefix)
+{
+	int i, heads;
+	struct alternate_object_database *alt;
+
+	errors_found = 0;
+	read_replace_refs = 0;
+
+	argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0);
+	if (write_lost_and_found) {
+		check_full = 1;
+		include_reflogs = 0;
+	}
+
+	fsck_head_link();
+	fsck_object_dir(get_object_directory());
+
+	prepare_alt_odb();
+	for (alt = alt_odb_list; alt; alt = alt->next) {
+		char namebuf[PATH_MAX];
+		int namelen = alt->name - alt->base;
+		memcpy(namebuf, alt->base, namelen);
+		namebuf[namelen - 1] = 0;
+		fsck_object_dir(namebuf);
+	}
+
+	if (check_full) {
+		struct packed_git *p;
+
+		prepare_packed_git();
+		for (p = packed_git; p; p = p->next)
+			/* verify gives error messages itself */
+			verify_pack(p);
+
+		for (p = packed_git; p; p = p->next) {
+			uint32_t j, num;
+			if (open_pack_index(p))
+				continue;
+			num = p->num_objects;
+			for (j = 0; j < num; j++)
+				fsck_sha1(nth_packed_object_sha1(p, j));
+		}
+	}
+
+	heads = 0;
+	for (i = 0; i < argc; i++) {
+		const char *arg = argv[i];
+		unsigned char sha1[20];
+		if (!get_sha1(arg, sha1)) {
+			struct object *obj = lookup_object(sha1);
+
+			/* Error is printed by lookup_object(). */
+			if (!obj)
+				continue;
+
+			obj->used = 1;
+			mark_object_reachable(obj);
+			heads++;
+			continue;
+		}
+		error("invalid parameter: expected sha1, got '%s'", arg);
+	}
+
+	/*
+	 * If we've not been given any explicit head information, do the
+	 * default ones from .git/refs. We also consider the index file
+	 * in this case (ie this implies --cache).
+	 */
+	if (!heads) {
+		get_default_heads();
+		keep_cache_objects = 1;
+	}
+
+	if (keep_cache_objects) {
+		read_cache();
+		for (i = 0; i < active_nr; i++) {
+			unsigned int mode;
+			struct blob *blob;
+			struct object *obj;
+
+			mode = active_cache[i]->ce_mode;
+			if (S_ISGITLINK(mode))
+				continue;
+			blob = lookup_blob(active_cache[i]->sha1);
+			if (!blob)
+				continue;
+			obj = &blob->object;
+			obj->used = 1;
+			mark_object_reachable(obj);
+		}
+		if (active_cache_tree)
+			fsck_cache_tree(active_cache_tree);
+	}
+
+	check_connectivity();
+	return errors_found;
+}
diff --git a/builtin/gc.c b/builtin/gc.c
new file mode 100644
index 0000000..c304638
--- /dev/null
+++ b/builtin/gc.c
@@ -0,0 +1,255 @@
+/*
+ * git gc builtin command
+ *
+ * Cleanup unreachable files and optimize the repository.
+ *
+ * Copyright (c) 2007 James Bowes
+ *
+ * Based on git-gc.sh, which is
+ *
+ * Copyright (c) 2006 Shawn O. Pearce
+ */
+
+#include "builtin.h"
+#include "cache.h"
+#include "parse-options.h"
+#include "run-command.h"
+
+#define FAILED_RUN "failed to run %s"
+
+static const char * const builtin_gc_usage[] = {
+	"git gc [options]",
+	NULL
+};
+
+static int pack_refs = 1;
+static int aggressive_window = 250;
+static int gc_auto_threshold = 6700;
+static int gc_auto_pack_limit = 50;
+static const char *prune_expire = "2.weeks.ago";
+
+#define MAX_ADD 10
+static const char *argv_pack_refs[] = {"pack-refs", "--all", "--prune", NULL};
+static const char *argv_reflog[] = {"reflog", "expire", "--all", NULL};
+static const char *argv_repack[MAX_ADD] = {"repack", "-d", "-l", NULL};
+static const char *argv_prune[] = {"prune", "--expire", NULL, NULL};
+static const char *argv_rerere[] = {"rerere", "gc", NULL};
+
+static int gc_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "gc.packrefs")) {
+		if (value && !strcmp(value, "notbare"))
+			pack_refs = -1;
+		else
+			pack_refs = git_config_bool(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "gc.aggressivewindow")) {
+		aggressive_window = git_config_int(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "gc.auto")) {
+		gc_auto_threshold = git_config_int(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "gc.autopacklimit")) {
+		gc_auto_pack_limit = git_config_int(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "gc.pruneexpire")) {
+		if (value && strcmp(value, "now")) {
+			unsigned long now = approxidate("now");
+			if (approxidate(value) >= now)
+				return error("Invalid %s: '%s'", var, value);
+		}
+		return git_config_string(&prune_expire, var, value);
+	}
+	return git_default_config(var, value, cb);
+}
+
+static void append_option(const char **cmd, const char *opt, int max_length)
+{
+	int i;
+
+	for (i = 0; cmd[i]; i++)
+		;
+
+	if (i + 2 >= max_length)
+		die("Too many options specified");
+	cmd[i++] = opt;
+	cmd[i] = NULL;
+}
+
+static int too_many_loose_objects(void)
+{
+	/*
+	 * Quickly check if a "gc" is needed, by estimating how
+	 * many loose objects there are.  Because SHA-1 is evenly
+	 * distributed, we can check only one and get a reasonable
+	 * estimate.
+	 */
+	char path[PATH_MAX];
+	const char *objdir = get_object_directory();
+	DIR *dir;
+	struct dirent *ent;
+	int auto_threshold;
+	int num_loose = 0;
+	int needed = 0;
+
+	if (gc_auto_threshold <= 0)
+		return 0;
+
+	if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
+		warning("insanely long object directory %.*s", 50, objdir);
+		return 0;
+	}
+	dir = opendir(path);
+	if (!dir)
+		return 0;
+
+	auto_threshold = (gc_auto_threshold + 255) / 256;
+	while ((ent = readdir(dir)) != NULL) {
+		if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
+		    ent->d_name[38] != '\0')
+			continue;
+		if (++num_loose > auto_threshold) {
+			needed = 1;
+			break;
+		}
+	}
+	closedir(dir);
+	return needed;
+}
+
+static int too_many_packs(void)
+{
+	struct packed_git *p;
+	int cnt;
+
+	if (gc_auto_pack_limit <= 0)
+		return 0;
+
+	prepare_packed_git();
+	for (cnt = 0, p = packed_git; p; p = p->next) {
+		if (!p->pack_local)
+			continue;
+		if (p->pack_keep)
+			continue;
+		/*
+		 * Perhaps check the size of the pack and count only
+		 * very small ones here?
+		 */
+		cnt++;
+	}
+	return gc_auto_pack_limit <= cnt;
+}
+
+static int need_to_gc(void)
+{
+	/*
+	 * Setting gc.auto to 0 or negative can disable the
+	 * automatic gc.
+	 */
+	if (gc_auto_threshold <= 0)
+		return 0;
+
+	/*
+	 * If there are too many loose objects, but not too many
+	 * packs, we run "repack -d -l".  If there are too many packs,
+	 * we run "repack -A -d -l".  Otherwise we tell the caller
+	 * there is no need.
+	 */
+	if (too_many_packs())
+		append_option(argv_repack,
+			      prune_expire && !strcmp(prune_expire, "now") ?
+			      "-a" : "-A",
+			      MAX_ADD);
+	else if (!too_many_loose_objects())
+		return 0;
+
+	if (run_hook(NULL, "pre-auto-gc", NULL))
+		return 0;
+	return 1;
+}
+
+int cmd_gc(int argc, const char **argv, const char *prefix)
+{
+	int aggressive = 0;
+	int auto_gc = 0;
+	int quiet = 0;
+	char buf[80];
+
+	struct option builtin_gc_options[] = {
+		OPT__QUIET(&quiet),
+		{ OPTION_STRING, 0, "prune", &prune_expire, "date",
+			"prune unreferenced objects",
+			PARSE_OPT_OPTARG, NULL, (intptr_t)prune_expire },
+		OPT_BOOLEAN(0, "aggressive", &aggressive, "be more thorough (increased runtime)"),
+		OPT_BOOLEAN(0, "auto", &auto_gc, "enable auto-gc mode"),
+		OPT_END()
+	};
+
+	git_config(gc_config, NULL);
+
+	if (pack_refs < 0)
+		pack_refs = !is_bare_repository();
+
+	argc = parse_options(argc, argv, prefix, builtin_gc_options,
+			     builtin_gc_usage, 0);
+	if (argc > 0)
+		usage_with_options(builtin_gc_usage, builtin_gc_options);
+
+	if (aggressive) {
+		append_option(argv_repack, "-f", MAX_ADD);
+		append_option(argv_repack, "--depth=250", MAX_ADD);
+		if (aggressive_window > 0) {
+			sprintf(buf, "--window=%d", aggressive_window);
+			append_option(argv_repack, buf, MAX_ADD);
+		}
+	}
+	if (quiet)
+		append_option(argv_repack, "-q", MAX_ADD);
+
+	if (auto_gc) {
+		/*
+		 * Auto-gc should be least intrusive as possible.
+		 */
+		if (!need_to_gc())
+			return 0;
+		fprintf(stderr,
+			"Auto packing the repository for optimum performance.%s\n",
+			quiet
+			? ""
+			: (" You may also\n"
+			   "run \"git gc\" manually. See "
+			   "\"git help gc\" for more information."));
+	} else
+		append_option(argv_repack,
+			      prune_expire && !strcmp(prune_expire, "now")
+			      ? "-a" : "-A",
+			      MAX_ADD);
+
+	if (pack_refs && run_command_v_opt(argv_pack_refs, RUN_GIT_CMD))
+		return error(FAILED_RUN, argv_pack_refs[0]);
+
+	if (run_command_v_opt(argv_reflog, RUN_GIT_CMD))
+		return error(FAILED_RUN, argv_reflog[0]);
+
+	if (run_command_v_opt(argv_repack, RUN_GIT_CMD))
+		return error(FAILED_RUN, argv_repack[0]);
+
+	if (prune_expire) {
+		argv_prune[2] = prune_expire;
+		if (run_command_v_opt(argv_prune, RUN_GIT_CMD))
+			return error(FAILED_RUN, argv_prune[0]);
+	}
+
+	if (run_command_v_opt(argv_rerere, RUN_GIT_CMD))
+		return error(FAILED_RUN, argv_rerere[0]);
+
+	if (auto_gc && too_many_loose_objects())
+		warning("There are too many unreachable loose objects; "
+			"run 'git prune' to remove them.");
+
+	return 0;
+}
diff --git a/builtin/grep.c b/builtin/grep.c
new file mode 100644
index 0000000..40b9a93
--- /dev/null
+++ b/builtin/grep.c
@@ -0,0 +1,1011 @@
+/*
+ * Builtin "git grep"
+ *
+ * Copyright (c) 2006 Junio C Hamano
+ */
+#include "cache.h"
+#include "blob.h"
+#include "tree.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree-walk.h"
+#include "builtin.h"
+#include "parse-options.h"
+#include "userdiff.h"
+#include "grep.h"
+#include "quote.h"
+#include "dir.h"
+
+#ifndef NO_PTHREADS
+#include "thread-utils.h"
+#include <pthread.h>
+#endif
+
+static char const * const grep_usage[] = {
+	"git grep [options] [-e] <pattern> [<rev>...] [[--] path...]",
+	NULL
+};
+
+static int use_threads = 1;
+
+#ifndef NO_PTHREADS
+#define THREADS 8
+static pthread_t threads[THREADS];
+
+static void *load_sha1(const unsigned char *sha1, unsigned long *size,
+		       const char *name);
+static void *load_file(const char *filename, size_t *sz);
+
+enum work_type {WORK_SHA1, WORK_FILE};
+
+/* We use one producer thread and THREADS consumer
+ * threads. The producer adds struct work_items to 'todo' and the
+ * consumers pick work items from the same array.
+ */
+struct work_item
+{
+	enum work_type type;
+	char *name;
+
+	/* if type == WORK_SHA1, then 'identifier' is a SHA1,
+	 * otherwise type == WORK_FILE, and 'identifier' is a NUL
+	 * terminated filename.
+	 */
+	void *identifier;
+	char done;
+	struct strbuf out;
+};
+
+/* In the range [todo_done, todo_start) in 'todo' we have work_items
+ * that have been or are processed by a consumer thread. We haven't
+ * written the result for these to stdout yet.
+ *
+ * The work_items in [todo_start, todo_end) are waiting to be picked
+ * up by a consumer thread.
+ *
+ * The ranges are modulo TODO_SIZE.
+ */
+#define TODO_SIZE 128
+static struct work_item todo[TODO_SIZE];
+static int todo_start;
+static int todo_end;
+static int todo_done;
+
+/* Has all work items been added? */
+static int all_work_added;
+
+/* This lock protects all the variables above. */
+static pthread_mutex_t grep_mutex;
+
+/* Used to serialize calls to read_sha1_file. */
+static pthread_mutex_t read_sha1_mutex;
+
+#define grep_lock() pthread_mutex_lock(&grep_mutex)
+#define grep_unlock() pthread_mutex_unlock(&grep_mutex)
+#define read_sha1_lock() pthread_mutex_lock(&read_sha1_mutex)
+#define read_sha1_unlock() pthread_mutex_unlock(&read_sha1_mutex)
+
+/* Signalled when a new work_item is added to todo. */
+static pthread_cond_t cond_add;
+
+/* Signalled when the result from one work_item is written to
+ * stdout.
+ */
+static pthread_cond_t cond_write;
+
+/* Signalled when we are finished with everything. */
+static pthread_cond_t cond_result;
+
+static void add_work(enum work_type type, char *name, void *id)
+{
+	grep_lock();
+
+	while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
+		pthread_cond_wait(&cond_write, &grep_mutex);
+	}
+
+	todo[todo_end].type = type;
+	todo[todo_end].name = name;
+	todo[todo_end].identifier = id;
+	todo[todo_end].done = 0;
+	strbuf_reset(&todo[todo_end].out);
+	todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
+
+	pthread_cond_signal(&cond_add);
+	grep_unlock();
+}
+
+static struct work_item *get_work(void)
+{
+	struct work_item *ret;
+
+	grep_lock();
+	while (todo_start == todo_end && !all_work_added) {
+		pthread_cond_wait(&cond_add, &grep_mutex);
+	}
+
+	if (todo_start == todo_end && all_work_added) {
+		ret = NULL;
+	} else {
+		ret = &todo[todo_start];
+		todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
+	}
+	grep_unlock();
+	return ret;
+}
+
+static void grep_sha1_async(struct grep_opt *opt, char *name,
+			    const unsigned char *sha1)
+{
+	unsigned char *s;
+	s = xmalloc(20);
+	memcpy(s, sha1, 20);
+	add_work(WORK_SHA1, name, s);
+}
+
+static void grep_file_async(struct grep_opt *opt, char *name,
+			    const char *filename)
+{
+	add_work(WORK_FILE, name, xstrdup(filename));
+}
+
+static void work_done(struct work_item *w)
+{
+	int old_done;
+
+	grep_lock();
+	w->done = 1;
+	old_done = todo_done;
+	for(; todo[todo_done].done && todo_done != todo_start;
+	    todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
+		w = &todo[todo_done];
+		write_or_die(1, w->out.buf, w->out.len);
+		free(w->name);
+		free(w->identifier);
+	}
+
+	if (old_done != todo_done)
+		pthread_cond_signal(&cond_write);
+
+	if (all_work_added && todo_done == todo_end)
+		pthread_cond_signal(&cond_result);
+
+	grep_unlock();
+}
+
+static void *run(void *arg)
+{
+	int hit = 0;
+	struct grep_opt *opt = arg;
+
+	while (1) {
+		struct work_item *w = get_work();
+		if (!w)
+			break;
+
+		opt->output_priv = w;
+		if (w->type == WORK_SHA1) {
+			unsigned long sz;
+			void* data = load_sha1(w->identifier, &sz, w->name);
+
+			if (data) {
+				hit |= grep_buffer(opt, w->name, data, sz);
+				free(data);
+			}
+		} else if (w->type == WORK_FILE) {
+			size_t sz;
+			void* data = load_file(w->identifier, &sz);
+			if (data) {
+				hit |= grep_buffer(opt, w->name, data, sz);
+				free(data);
+			}
+		} else {
+			assert(0);
+		}
+
+		work_done(w);
+	}
+	free_grep_patterns(arg);
+	free(arg);
+
+	return (void*) (intptr_t) hit;
+}
+
+static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
+{
+	struct work_item *w = opt->output_priv;
+	strbuf_add(&w->out, buf, size);
+}
+
+static void start_threads(struct grep_opt *opt)
+{
+	int i;
+
+	pthread_mutex_init(&grep_mutex, NULL);
+	pthread_mutex_init(&read_sha1_mutex, NULL);
+	pthread_cond_init(&cond_add, NULL);
+	pthread_cond_init(&cond_write, NULL);
+	pthread_cond_init(&cond_result, NULL);
+
+	for (i = 0; i < ARRAY_SIZE(todo); i++) {
+		strbuf_init(&todo[i].out, 0);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(threads); i++) {
+		int err;
+		struct grep_opt *o = grep_opt_dup(opt);
+		o->output = strbuf_out;
+		compile_grep_patterns(o);
+		err = pthread_create(&threads[i], NULL, run, o);
+
+		if (err)
+			die("grep: failed to create thread: %s",
+			    strerror(err));
+	}
+}
+
+static int wait_all(void)
+{
+	int hit = 0;
+	int i;
+
+	grep_lock();
+	all_work_added = 1;
+
+	/* Wait until all work is done. */
+	while (todo_done != todo_end)
+		pthread_cond_wait(&cond_result, &grep_mutex);
+
+	/* Wake up all the consumer threads so they can see that there
+	 * is no more work to do.
+	 */
+	pthread_cond_broadcast(&cond_add);
+	grep_unlock();
+
+	for (i = 0; i < ARRAY_SIZE(threads); i++) {
+		void *h;
+		pthread_join(threads[i], &h);
+		hit |= (int) (intptr_t) h;
+	}
+
+	pthread_mutex_destroy(&grep_mutex);
+	pthread_mutex_destroy(&read_sha1_mutex);
+	pthread_cond_destroy(&cond_add);
+	pthread_cond_destroy(&cond_write);
+	pthread_cond_destroy(&cond_result);
+
+	return hit;
+}
+#else /* !NO_PTHREADS */
+#define read_sha1_lock()
+#define read_sha1_unlock()
+
+static int wait_all(void)
+{
+	return 0;
+}
+#endif
+
+static int grep_config(const char *var, const char *value, void *cb)
+{
+	struct grep_opt *opt = cb;
+
+	switch (userdiff_config(var, value)) {
+	case 0: break;
+	case -1: return -1;
+	default: return 0;
+	}
+
+	if (!strcmp(var, "color.grep")) {
+		opt->color = git_config_colorbool(var, value, -1);
+		return 0;
+	}
+	if (!strcmp(var, "color.grep.match")) {
+		if (!value)
+			return config_error_nonbool(var);
+		color_parse(value, var, opt->color_match);
+		return 0;
+	}
+	return git_color_default_config(var, value, cb);
+}
+
+/*
+ * Return non-zero if max_depth is negative or path has no more then max_depth
+ * slashes.
+ */
+static int accept_subdir(const char *path, int max_depth)
+{
+	if (max_depth < 0)
+		return 1;
+
+	while ((path = strchr(path, '/')) != NULL) {
+		max_depth--;
+		if (max_depth < 0)
+			return 0;
+		path++;
+	}
+	return 1;
+}
+
+/*
+ * Return non-zero if name is a subdirectory of match and is not too deep.
+ */
+static int is_subdir(const char *name, int namelen,
+		const char *match, int matchlen, int max_depth)
+{
+	if (matchlen > namelen || strncmp(name, match, matchlen))
+		return 0;
+
+	if (name[matchlen] == '\0') /* exact match */
+		return 1;
+
+	if (!matchlen || match[matchlen-1] == '/' || name[matchlen] == '/')
+		return accept_subdir(name + matchlen + 1, max_depth);
+
+	return 0;
+}
+
+/*
+ * git grep pathspecs are somewhat different from diff-tree pathspecs;
+ * pathname wildcards are allowed.
+ */
+static int pathspec_matches(const char **paths, const char *name, int max_depth)
+{
+	int namelen, i;
+	if (!paths || !*paths)
+		return accept_subdir(name, max_depth);
+	namelen = strlen(name);
+	for (i = 0; paths[i]; i++) {
+		const char *match = paths[i];
+		int matchlen = strlen(match);
+		const char *cp, *meta;
+
+		if (is_subdir(name, namelen, match, matchlen, max_depth))
+			return 1;
+		if (!fnmatch(match, name, 0))
+			return 1;
+		if (name[namelen-1] != '/')
+			continue;
+
+		/* We are being asked if the directory ("name") is worth
+		 * descending into.
+		 *
+		 * Find the longest leading directory name that does
+		 * not have metacharacter in the pathspec; the name
+		 * we are looking at must overlap with that directory.
+		 */
+		for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
+			char ch = *cp;
+			if (ch == '*' || ch == '[' || ch == '?') {
+				meta = cp;
+				break;
+			}
+		}
+		if (!meta)
+			meta = cp; /* fully literal */
+
+		if (namelen <= meta - match) {
+			/* Looking at "Documentation/" and
+			 * the pattern says "Documentation/howto/", or
+			 * "Documentation/diff*.txt".  The name we
+			 * have should match prefix.
+			 */
+			if (!memcmp(match, name, namelen))
+				return 1;
+			continue;
+		}
+
+		if (meta - match < namelen) {
+			/* Looking at "Documentation/howto/" and
+			 * the pattern says "Documentation/h*";
+			 * match up to "Do.../h"; this avoids descending
+			 * into "Documentation/technical/".
+			 */
+			if (!memcmp(match, name, meta - match))
+				return 1;
+			continue;
+		}
+	}
+	return 0;
+}
+
+static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
+{
+	void *data;
+
+	if (use_threads) {
+		read_sha1_lock();
+		data = read_sha1_file(sha1, type, size);
+		read_sha1_unlock();
+	} else {
+		data = read_sha1_file(sha1, type, size);
+	}
+	return data;
+}
+
+static void *load_sha1(const unsigned char *sha1, unsigned long *size,
+		       const char *name)
+{
+	enum object_type type;
+	void *data = lock_and_read_sha1_file(sha1, &type, size);
+
+	if (!data)
+		error("'%s': unable to read %s", name, sha1_to_hex(sha1));
+
+	return data;
+}
+
+static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
+		     const char *filename, int tree_name_len)
+{
+	struct strbuf pathbuf = STRBUF_INIT;
+	char *name;
+
+	if (opt->relative && opt->prefix_length) {
+		quote_path_relative(filename + tree_name_len, -1, &pathbuf,
+				    opt->prefix);
+		strbuf_insert(&pathbuf, 0, filename, tree_name_len);
+	} else {
+		strbuf_addstr(&pathbuf, filename);
+	}
+
+	name = strbuf_detach(&pathbuf, NULL);
+
+#ifndef NO_PTHREADS
+	if (use_threads) {
+		grep_sha1_async(opt, name, sha1);
+		return 0;
+	} else
+#endif
+	{
+		int hit;
+		unsigned long sz;
+		void *data = load_sha1(sha1, &sz, name);
+		if (!data)
+			hit = 0;
+		else
+			hit = grep_buffer(opt, name, data, sz);
+
+		free(data);
+		free(name);
+		return hit;
+	}
+}
+
+static void *load_file(const char *filename, size_t *sz)
+{
+	struct stat st;
+	char *data;
+	int i;
+
+	if (lstat(filename, &st) < 0) {
+	err_ret:
+		if (errno != ENOENT)
+			error("'%s': %s", filename, strerror(errno));
+		return 0;
+	}
+	if (!S_ISREG(st.st_mode))
+		return 0;
+	*sz = xsize_t(st.st_size);
+	i = open(filename, O_RDONLY);
+	if (i < 0)
+		goto err_ret;
+	data = xmalloc(*sz + 1);
+	if (st.st_size != read_in_full(i, data, *sz)) {
+		error("'%s': short read %s", filename, strerror(errno));
+		close(i);
+		free(data);
+		return 0;
+	}
+	close(i);
+	data[*sz] = 0;
+	return data;
+}
+
+static int grep_file(struct grep_opt *opt, const char *filename)
+{
+	struct strbuf buf = STRBUF_INIT;
+	char *name;
+
+	if (opt->relative && opt->prefix_length)
+		quote_path_relative(filename, -1, &buf, opt->prefix);
+	else
+		strbuf_addstr(&buf, filename);
+	name = strbuf_detach(&buf, NULL);
+
+#ifndef NO_PTHREADS
+	if (use_threads) {
+		grep_file_async(opt, name, filename);
+		return 0;
+	} else
+#endif
+	{
+		int hit;
+		size_t sz;
+		void *data = load_file(filename, &sz);
+		if (!data)
+			hit = 0;
+		else
+			hit = grep_buffer(opt, name, data, sz);
+
+		free(data);
+		free(name);
+		return hit;
+	}
+}
+
+static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
+{
+	int hit = 0;
+	int nr;
+	read_cache();
+
+	for (nr = 0; nr < active_nr; nr++) {
+		struct cache_entry *ce = active_cache[nr];
+		if (!S_ISREG(ce->ce_mode))
+			continue;
+		if (!pathspec_matches(paths, ce->name, opt->max_depth))
+			continue;
+		/*
+		 * If CE_VALID is on, we assume worktree file and its cache entry
+		 * are identical, even if worktree file has been modified, so use
+		 * cache version instead
+		 */
+		if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
+			if (ce_stage(ce))
+				continue;
+			hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
+		}
+		else
+			hit |= grep_file(opt, ce->name);
+		if (ce_stage(ce)) {
+			do {
+				nr++;
+			} while (nr < active_nr &&
+				 !strcmp(ce->name, active_cache[nr]->name));
+			nr--; /* compensate for loop control */
+		}
+		if (hit && opt->status_only)
+			break;
+	}
+	free_grep_patterns(opt);
+	return hit;
+}
+
+static int grep_tree(struct grep_opt *opt, const char **paths,
+		     struct tree_desc *tree,
+		     const char *tree_name, const char *base)
+{
+	int len;
+	int hit = 0;
+	struct name_entry entry;
+	char *down;
+	int tn_len = strlen(tree_name);
+	struct strbuf pathbuf;
+
+	strbuf_init(&pathbuf, PATH_MAX + tn_len);
+
+	if (tn_len) {
+		strbuf_add(&pathbuf, tree_name, tn_len);
+		strbuf_addch(&pathbuf, ':');
+		tn_len = pathbuf.len;
+	}
+	strbuf_addstr(&pathbuf, base);
+	len = pathbuf.len;
+
+	while (tree_entry(tree, &entry)) {
+		int te_len = tree_entry_len(entry.path, entry.sha1);
+		pathbuf.len = len;
+		strbuf_add(&pathbuf, entry.path, te_len);
+
+		if (S_ISDIR(entry.mode))
+			/* Match "abc/" against pathspec to
+			 * decide if we want to descend into "abc"
+			 * directory.
+			 */
+			strbuf_addch(&pathbuf, '/');
+
+		down = pathbuf.buf + tn_len;
+		if (!pathspec_matches(paths, down, opt->max_depth))
+			;
+		else if (S_ISREG(entry.mode))
+			hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
+		else if (S_ISDIR(entry.mode)) {
+			enum object_type type;
+			struct tree_desc sub;
+			void *data;
+			unsigned long size;
+
+			data = lock_and_read_sha1_file(entry.sha1, &type, &size);
+			if (!data)
+				die("unable to read tree (%s)",
+				    sha1_to_hex(entry.sha1));
+			init_tree_desc(&sub, data, size);
+			hit |= grep_tree(opt, paths, &sub, tree_name, down);
+			free(data);
+		}
+		if (hit && opt->status_only)
+			break;
+	}
+	strbuf_release(&pathbuf);
+	return hit;
+}
+
+static int grep_object(struct grep_opt *opt, const char **paths,
+		       struct object *obj, const char *name)
+{
+	if (obj->type == OBJ_BLOB)
+		return grep_sha1(opt, obj->sha1, name, 0);
+	if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
+		struct tree_desc tree;
+		void *data;
+		unsigned long size;
+		int hit;
+		data = read_object_with_reference(obj->sha1, tree_type,
+						  &size, NULL);
+		if (!data)
+			die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
+		init_tree_desc(&tree, data, size);
+		hit = grep_tree(opt, paths, &tree, name, "");
+		free(data);
+		return hit;
+	}
+	die("unable to grep from object of type %s", typename(obj->type));
+}
+
+static int grep_directory(struct grep_opt *opt, const char **paths)
+{
+	struct dir_struct dir;
+	int i, hit = 0;
+
+	memset(&dir, 0, sizeof(dir));
+	setup_standard_excludes(&dir);
+
+	fill_directory(&dir, paths);
+	for (i = 0; i < dir.nr; i++) {
+		hit |= grep_file(opt, dir.entries[i]->name);
+		if (hit && opt->status_only)
+			break;
+	}
+	free_grep_patterns(opt);
+	return hit;
+}
+
+static int context_callback(const struct option *opt, const char *arg,
+			    int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	int value;
+	const char *endp;
+
+	if (unset) {
+		grep_opt->pre_context = grep_opt->post_context = 0;
+		return 0;
+	}
+	value = strtol(arg, (char **)&endp, 10);
+	if (*endp) {
+		return error("switch `%c' expects a numerical value",
+			     opt->short_name);
+	}
+	grep_opt->pre_context = grep_opt->post_context = value;
+	return 0;
+}
+
+static int file_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	FILE *patterns;
+	int lno = 0;
+	struct strbuf sb = STRBUF_INIT;
+
+	patterns = fopen(arg, "r");
+	if (!patterns)
+		die_errno("cannot open '%s'", arg);
+	while (strbuf_getline(&sb, patterns, '\n') == 0) {
+		/* ignore empty line like grep does */
+		if (sb.len == 0)
+			continue;
+		append_grep_pattern(grep_opt, strbuf_detach(&sb, NULL), arg,
+				    ++lno, GREP_PATTERN);
+	}
+	fclose(patterns);
+	strbuf_release(&sb);
+	return 0;
+}
+
+static int not_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
+	return 0;
+}
+
+static int and_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
+	return 0;
+}
+
+static int open_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
+	return 0;
+}
+
+static int close_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
+	return 0;
+}
+
+static int pattern_callback(const struct option *opt, const char *arg,
+			    int unset)
+{
+	struct grep_opt *grep_opt = opt->value;
+	append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
+	return 0;
+}
+
+static int help_callback(const struct option *opt, const char *arg, int unset)
+{
+	return -1;
+}
+
+int cmd_grep(int argc, const char **argv, const char *prefix)
+{
+	int hit = 0;
+	int cached = 0;
+	int seen_dashdash = 0;
+	int external_grep_allowed__ignored;
+	struct grep_opt opt;
+	struct object_array list = { 0, 0, NULL };
+	const char **paths = NULL;
+	int i;
+	int dummy;
+	int nongit = 0, use_index = 1;
+	struct option options[] = {
+		OPT_BOOLEAN(0, "cached", &cached,
+			"search in index instead of in the work tree"),
+		OPT_BOOLEAN(0, "index", &use_index,
+			"--no-index finds in contents not managed by git"),
+		OPT_GROUP(""),
+		OPT_BOOLEAN('v', "invert-match", &opt.invert,
+			"show non-matching lines"),
+		OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
+			"case insensitive matching"),
+		OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
+			"match patterns only at word boundaries"),
+		OPT_SET_INT('a', "text", &opt.binary,
+			"process binary files as text", GREP_BINARY_TEXT),
+		OPT_SET_INT('I', NULL, &opt.binary,
+			"don't match patterns in binary files",
+			GREP_BINARY_NOMATCH),
+		{ OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
+			"descend at most <depth> levels", PARSE_OPT_NONEG,
+			NULL, 1 },
+		OPT_GROUP(""),
+		OPT_BIT('E', "extended-regexp", &opt.regflags,
+			"use extended POSIX regular expressions", REG_EXTENDED),
+		OPT_NEGBIT('G', "basic-regexp", &opt.regflags,
+			"use basic POSIX regular expressions (default)",
+			REG_EXTENDED),
+		OPT_BOOLEAN('F', "fixed-strings", &opt.fixed,
+			"interpret patterns as fixed strings"),
+		OPT_GROUP(""),
+		OPT_BOOLEAN('n', NULL, &opt.linenum, "show line numbers"),
+		OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
+		OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
+		OPT_NEGBIT(0, "full-name", &opt.relative,
+			"show filenames relative to top directory", 1),
+		OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
+			"show only filenames instead of matching lines"),
+		OPT_BOOLEAN(0, "name-only", &opt.name_only,
+			"synonym for --files-with-matches"),
+		OPT_BOOLEAN('L', "files-without-match",
+			&opt.unmatch_name_only,
+			"show only the names of files without match"),
+		OPT_BOOLEAN('z', "null", &opt.null_following_name,
+			"print NUL after filenames"),
+		OPT_BOOLEAN('c', "count", &opt.count,
+			"show the number of matches instead of matching lines"),
+		OPT__COLOR(&opt.color, "highlight matches"),
+		OPT_GROUP(""),
+		OPT_CALLBACK('C', NULL, &opt, "n",
+			"show <n> context lines before and after matches",
+			context_callback),
+		OPT_INTEGER('B', NULL, &opt.pre_context,
+			"show <n> context lines before matches"),
+		OPT_INTEGER('A', NULL, &opt.post_context,
+			"show <n> context lines after matches"),
+		OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
+			context_callback),
+		OPT_BOOLEAN('p', "show-function", &opt.funcname,
+			"show a line with the function name before matches"),
+		OPT_GROUP(""),
+		OPT_CALLBACK('f', NULL, &opt, "file",
+			"read patterns from file", file_callback),
+		{ OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
+			"match <pattern>", PARSE_OPT_NONEG, pattern_callback },
+		{ OPTION_CALLBACK, 0, "and", &opt, NULL,
+		  "combine patterns specified with -e",
+		  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
+		OPT_BOOLEAN(0, "or", &dummy, ""),
+		{ OPTION_CALLBACK, 0, "not", &opt, NULL, "",
+		  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
+		{ OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
+		  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
+		  open_callback },
+		{ OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
+		  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
+		  close_callback },
+		OPT_BOOLEAN('q', "quiet", &opt.status_only,
+			    "indicate hit with exit status without output"),
+		OPT_BOOLEAN(0, "all-match", &opt.all_match,
+			"show only matches from files that match all patterns"),
+		OPT_GROUP(""),
+		OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
+			    "allow calling of grep(1) (ignored by this build)"),
+		{ OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
+		  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
+		OPT_END()
+	};
+
+	prefix = setup_git_directory_gently(&nongit);
+
+	/*
+	 * 'git grep -h', unlike 'git grep -h <pattern>', is a request
+	 * to show usage information and exit.
+	 */
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage_with_options(grep_usage, options);
+
+	memset(&opt, 0, sizeof(opt));
+	opt.prefix = prefix;
+	opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
+	opt.relative = 1;
+	opt.pathname = 1;
+	opt.pattern_tail = &opt.pattern_list;
+	opt.header_tail = &opt.header_list;
+	opt.regflags = REG_NEWLINE;
+	opt.max_depth = -1;
+
+	strcpy(opt.color_match, GIT_COLOR_RED GIT_COLOR_BOLD);
+	opt.color = -1;
+	git_config(grep_config, &opt);
+	if (opt.color == -1)
+		opt.color = git_use_color_default;
+
+	/*
+	 * If there is no -- then the paths must exist in the working
+	 * tree.  If there is no explicit pattern specified with -e or
+	 * -f, we take the first unrecognized non option to be the
+	 * pattern, but then what follows it must be zero or more
+	 * valid refs up to the -- (if exists), and then existing
+	 * paths.  If there is an explicit pattern, then the first
+	 * unrecognized non option is the beginning of the refs list
+	 * that continues up to the -- (if exists), and then paths.
+	 */
+	argc = parse_options(argc, argv, prefix, options, grep_usage,
+			     PARSE_OPT_KEEP_DASHDASH |
+			     PARSE_OPT_STOP_AT_NON_OPTION |
+			     PARSE_OPT_NO_INTERNAL_HELP);
+
+	if (use_index && nongit)
+		/* die the same way as if we did it at the beginning */
+		setup_git_directory();
+
+	/*
+	 * skip a -- separator; we know it cannot be
+	 * separating revisions from pathnames if
+	 * we haven't even had any patterns yet
+	 */
+	if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
+		argv++;
+		argc--;
+	}
+
+	/* First unrecognized non-option token */
+	if (argc > 0 && !opt.pattern_list) {
+		append_grep_pattern(&opt, argv[0], "command line", 0,
+				    GREP_PATTERN);
+		argv++;
+		argc--;
+	}
+
+	if (!opt.pattern_list)
+		die("no pattern given.");
+	if (!opt.fixed && opt.ignore_case)
+		opt.regflags |= REG_ICASE;
+	if ((opt.regflags != REG_NEWLINE) && opt.fixed)
+		die("cannot mix --fixed-strings and regexp");
+
+#ifndef NO_PTHREADS
+	if (online_cpus() == 1 || !grep_threads_ok(&opt))
+		use_threads = 0;
+
+	if (use_threads)
+		start_threads(&opt);
+#else
+	use_threads = 0;
+#endif
+
+	compile_grep_patterns(&opt);
+
+	/* Check revs and then paths */
+	for (i = 0; i < argc; i++) {
+		const char *arg = argv[i];
+		unsigned char sha1[20];
+		/* Is it a rev? */
+		if (!get_sha1(arg, sha1)) {
+			struct object *object = parse_object(sha1);
+			if (!object)
+				die("bad object %s", arg);
+			add_object_array(object, arg, &list);
+			continue;
+		}
+		if (!strcmp(arg, "--")) {
+			i++;
+			seen_dashdash = 1;
+		}
+		break;
+	}
+
+	/* The rest are paths */
+	if (!seen_dashdash) {
+		int j;
+		for (j = i; j < argc; j++)
+			verify_filename(prefix, argv[j]);
+	}
+
+	if (i < argc)
+		paths = get_pathspec(prefix, argv + i);
+	else if (prefix) {
+		paths = xcalloc(2, sizeof(const char *));
+		paths[0] = prefix;
+		paths[1] = NULL;
+	}
+
+	if (!use_index) {
+		int hit;
+		if (cached)
+			die("--cached cannot be used with --no-index.");
+		if (list.nr)
+			die("--no-index cannot be used with revs.");
+		hit = grep_directory(&opt, paths);
+		if (use_threads)
+			hit |= wait_all();
+		return !hit;
+	}
+
+	if (!list.nr) {
+		int hit;
+		if (!cached)
+			setup_work_tree();
+
+		hit = grep_cache(&opt, paths, cached);
+		if (use_threads)
+			hit |= wait_all();
+		return !hit;
+	}
+
+	if (cached)
+		die("both --cached and trees are given.");
+
+	for (i = 0; i < list.nr; i++) {
+		struct object *real_obj;
+		real_obj = deref_tag(list.objects[i].item, NULL, 0);
+		if (grep_object(&opt, paths, real_obj, list.objects[i].name)) {
+			hit = 1;
+			if (opt.status_only)
+				break;
+		}
+	}
+
+	if (use_threads)
+		hit |= wait_all();
+	free_grep_patterns(&opt);
+	return !hit;
+}
diff --git a/builtin/hash-object.c b/builtin/hash-object.c
new file mode 100644
index 0000000..080af1a
--- /dev/null
+++ b/builtin/hash-object.c
@@ -0,0 +1,134 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ * Copyright (C) Junio C Hamano, 2005
+ */
+#include "cache.h"
+#include "blob.h"
+#include "quote.h"
+#include "parse-options.h"
+#include "exec_cmd.h"
+
+static void hash_fd(int fd, const char *type, int write_object, const char *path)
+{
+	struct stat st;
+	unsigned char sha1[20];
+	if (fstat(fd, &st) < 0 ||
+	    index_fd(sha1, fd, &st, write_object, type_from_string(type), path))
+		die(write_object
+		    ? "Unable to add %s to database"
+		    : "Unable to hash %s", path);
+	printf("%s\n", sha1_to_hex(sha1));
+	maybe_flush_or_die(stdout, "hash to stdout");
+}
+
+static void hash_object(const char *path, const char *type, int write_object,
+			const char *vpath)
+{
+	int fd;
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		die_errno("Cannot open '%s'", path);
+	hash_fd(fd, type, write_object, vpath);
+}
+
+static int no_filters;
+
+static void hash_stdin_paths(const char *type, int write_objects)
+{
+	struct strbuf buf = STRBUF_INIT, nbuf = STRBUF_INIT;
+
+	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
+		if (buf.buf[0] == '"') {
+			strbuf_reset(&nbuf);
+			if (unquote_c_style(&nbuf, buf.buf, NULL))
+				die("line is badly quoted");
+			strbuf_swap(&buf, &nbuf);
+		}
+		hash_object(buf.buf, type, write_objects,
+		    no_filters ? NULL : buf.buf);
+	}
+	strbuf_release(&buf);
+	strbuf_release(&nbuf);
+}
+
+static const char * const hash_object_usage[] = {
+	"git hash-object [-t <type>] [-w] [--path=<file>|--no-filters] [--stdin] [--] <file>...",
+	"git hash-object  --stdin-paths < <list-of-paths>",
+	NULL
+};
+
+static const char *type;
+static int write_object;
+static int hashstdin;
+static int stdin_paths;
+static const char *vpath;
+
+static const struct option hash_object_options[] = {
+	OPT_STRING('t', NULL, &type, "type", "object type"),
+	OPT_BOOLEAN('w', NULL, &write_object, "write the object into the object database"),
+	OPT_BOOLEAN( 0 , "stdin", &hashstdin, "read the object from stdin"),
+	OPT_BOOLEAN( 0 , "stdin-paths", &stdin_paths, "read file names from stdin"),
+	OPT_BOOLEAN( 0 , "no-filters", &no_filters, "store file as is without filters"),
+	OPT_STRING( 0 , "path", &vpath, "file", "process file as it were from this path"),
+	OPT_END()
+};
+
+int cmd_hash_object(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	int prefix_length = -1;
+	const char *errstr = NULL;
+
+	type = blob_type;
+
+	argc = parse_options(argc, argv, NULL, hash_object_options,
+			     hash_object_usage, 0);
+
+	if (write_object) {
+		prefix = setup_git_directory();
+		prefix_length = prefix ? strlen(prefix) : 0;
+		if (vpath && prefix)
+			vpath = prefix_filename(prefix, prefix_length, vpath);
+	}
+
+	git_config(git_default_config, NULL);
+
+	if (stdin_paths) {
+		if (hashstdin)
+			errstr = "Can't use --stdin-paths with --stdin";
+		else if (argc)
+			errstr = "Can't specify files with --stdin-paths";
+		else if (vpath)
+			errstr = "Can't use --stdin-paths with --path";
+	}
+	else {
+		if (hashstdin > 1)
+			errstr = "Multiple --stdin arguments are not supported";
+		if (vpath && no_filters)
+			errstr = "Can't use --path with --no-filters";
+	}
+
+	if (errstr) {
+		error("%s", errstr);
+		usage_with_options(hash_object_usage, hash_object_options);
+	}
+
+	if (hashstdin)
+		hash_fd(0, type, write_object, vpath);
+
+	for (i = 0 ; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (0 <= prefix_length)
+			arg = prefix_filename(prefix, prefix_length, arg);
+		hash_object(arg, type, write_object,
+			    no_filters ? NULL : vpath ? vpath : arg);
+	}
+
+	if (stdin_paths)
+		hash_stdin_paths(type, write_object);
+
+	return 0;
+}
diff --git a/builtin/help.c b/builtin/help.c
new file mode 100644
index 0000000..3182a2b
--- /dev/null
+++ b/builtin/help.c
@@ -0,0 +1,466 @@
+/*
+ * builtin-help.c
+ *
+ * Builtin help command
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "common-cmds.h"
+#include "parse-options.h"
+#include "run-command.h"
+#include "help.h"
+
+static struct man_viewer_list {
+	struct man_viewer_list *next;
+	char name[FLEX_ARRAY];
+} *man_viewer_list;
+
+static struct man_viewer_info_list {
+	struct man_viewer_info_list *next;
+	const char *info;
+	char name[FLEX_ARRAY];
+} *man_viewer_info_list;
+
+enum help_format {
+	HELP_FORMAT_NONE,
+	HELP_FORMAT_MAN,
+	HELP_FORMAT_INFO,
+	HELP_FORMAT_WEB,
+};
+
+static int show_all = 0;
+static enum help_format help_format = HELP_FORMAT_NONE;
+static struct option builtin_help_options[] = {
+	OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
+	OPT_SET_INT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
+	OPT_SET_INT('w', "web", &help_format, "show manual in web browser",
+			HELP_FORMAT_WEB),
+	OPT_SET_INT('i', "info", &help_format, "show info page",
+			HELP_FORMAT_INFO),
+	OPT_END(),
+};
+
+static const char * const builtin_help_usage[] = {
+	"git help [--all] [--man|--web|--info] [command]",
+	NULL
+};
+
+static enum help_format parse_help_format(const char *format)
+{
+	if (!strcmp(format, "man"))
+		return HELP_FORMAT_MAN;
+	if (!strcmp(format, "info"))
+		return HELP_FORMAT_INFO;
+	if (!strcmp(format, "web") || !strcmp(format, "html"))
+		return HELP_FORMAT_WEB;
+	die("unrecognized help format '%s'", format);
+}
+
+static const char *get_man_viewer_info(const char *name)
+{
+	struct man_viewer_info_list *viewer;
+
+	for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
+	{
+		if (!strcasecmp(name, viewer->name))
+			return viewer->info;
+	}
+	return NULL;
+}
+
+static int check_emacsclient_version(void)
+{
+	struct strbuf buffer = STRBUF_INIT;
+	struct child_process ec_process;
+	const char *argv_ec[] = { "emacsclient", "--version", NULL };
+	int version;
+
+	/* emacsclient prints its version number on stderr */
+	memset(&ec_process, 0, sizeof(ec_process));
+	ec_process.argv = argv_ec;
+	ec_process.err = -1;
+	ec_process.stdout_to_stderr = 1;
+	if (start_command(&ec_process))
+		return error("Failed to start emacsclient.");
+
+	strbuf_read(&buffer, ec_process.err, 20);
+	close(ec_process.err);
+
+	/*
+	 * Don't bother checking return value, because "emacsclient --version"
+	 * seems to always exits with code 1.
+	 */
+	finish_command(&ec_process);
+
+	if (prefixcmp(buffer.buf, "emacsclient")) {
+		strbuf_release(&buffer);
+		return error("Failed to parse emacsclient version.");
+	}
+
+	strbuf_remove(&buffer, 0, strlen("emacsclient"));
+	version = atoi(buffer.buf);
+
+	if (version < 22) {
+		strbuf_release(&buffer);
+		return error("emacsclient version '%d' too old (< 22).",
+			version);
+	}
+
+	strbuf_release(&buffer);
+	return 0;
+}
+
+static void exec_woman_emacs(const char *path, const char *page)
+{
+	if (!check_emacsclient_version()) {
+		/* This works only with emacsclient version >= 22. */
+		struct strbuf man_page = STRBUF_INIT;
+
+		if (!path)
+			path = "emacsclient";
+		strbuf_addf(&man_page, "(woman \"%s\")", page);
+		execlp(path, "emacsclient", "-e", man_page.buf, NULL);
+		warning("failed to exec '%s': %s", path, strerror(errno));
+	}
+}
+
+static void exec_man_konqueror(const char *path, const char *page)
+{
+	const char *display = getenv("DISPLAY");
+	if (display && *display) {
+		struct strbuf man_page = STRBUF_INIT;
+		const char *filename = "kfmclient";
+
+		/* It's simpler to launch konqueror using kfmclient. */
+		if (path) {
+			const char *file = strrchr(path, '/');
+			if (file && !strcmp(file + 1, "konqueror")) {
+				char *new = xstrdup(path);
+				char *dest = strrchr(new, '/');
+
+				/* strlen("konqueror") == strlen("kfmclient") */
+				strcpy(dest + 1, "kfmclient");
+				path = new;
+			}
+			if (file)
+				filename = file;
+		} else
+			path = "kfmclient";
+		strbuf_addf(&man_page, "man:%s(1)", page);
+		execlp(path, filename, "newTab", man_page.buf, NULL);
+		warning("failed to exec '%s': %s", path, strerror(errno));
+	}
+}
+
+static void exec_man_man(const char *path, const char *page)
+{
+	if (!path)
+		path = "man";
+	execlp(path, "man", page, NULL);
+	warning("failed to exec '%s': %s", path, strerror(errno));
+}
+
+static void exec_man_cmd(const char *cmd, const char *page)
+{
+	struct strbuf shell_cmd = STRBUF_INIT;
+	strbuf_addf(&shell_cmd, "%s %s", cmd, page);
+	execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
+	warning("failed to exec '%s': %s", cmd, strerror(errno));
+}
+
+static void add_man_viewer(const char *name)
+{
+	struct man_viewer_list **p = &man_viewer_list;
+	size_t len = strlen(name);
+
+	while (*p)
+		p = &((*p)->next);
+	*p = xcalloc(1, (sizeof(**p) + len + 1));
+	strncpy((*p)->name, name, len);
+}
+
+static int supported_man_viewer(const char *name, size_t len)
+{
+	return (!strncasecmp("man", name, len) ||
+		!strncasecmp("woman", name, len) ||
+		!strncasecmp("konqueror", name, len));
+}
+
+static void do_add_man_viewer_info(const char *name,
+				   size_t len,
+				   const char *value)
+{
+	struct man_viewer_info_list *new = xcalloc(1, sizeof(*new) + len + 1);
+
+	strncpy(new->name, name, len);
+	new->info = xstrdup(value);
+	new->next = man_viewer_info_list;
+	man_viewer_info_list = new;
+}
+
+static int add_man_viewer_path(const char *name,
+			       size_t len,
+			       const char *value)
+{
+	if (supported_man_viewer(name, len))
+		do_add_man_viewer_info(name, len, value);
+	else
+		warning("'%s': path for unsupported man viewer.\n"
+			"Please consider using 'man.<tool>.cmd' instead.",
+			name);
+
+	return 0;
+}
+
+static int add_man_viewer_cmd(const char *name,
+			      size_t len,
+			      const char *value)
+{
+	if (supported_man_viewer(name, len))
+		warning("'%s': cmd for supported man viewer.\n"
+			"Please consider using 'man.<tool>.path' instead.",
+			name);
+	else
+		do_add_man_viewer_info(name, len, value);
+
+	return 0;
+}
+
+static int add_man_viewer_info(const char *var, const char *value)
+{
+	const char *name = var + 4;
+	const char *subkey = strrchr(name, '.');
+
+	if (!subkey)
+		return 0;
+
+	if (!strcmp(subkey, ".path")) {
+		if (!value)
+			return config_error_nonbool(var);
+		return add_man_viewer_path(name, subkey - name, value);
+	}
+	if (!strcmp(subkey, ".cmd")) {
+		if (!value)
+			return config_error_nonbool(var);
+		return add_man_viewer_cmd(name, subkey - name, value);
+	}
+
+	return 0;
+}
+
+static int git_help_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "help.format")) {
+		if (!value)
+			return config_error_nonbool(var);
+		help_format = parse_help_format(value);
+		return 0;
+	}
+	if (!strcmp(var, "man.viewer")) {
+		if (!value)
+			return config_error_nonbool(var);
+		add_man_viewer(value);
+		return 0;
+	}
+	if (!prefixcmp(var, "man."))
+		return add_man_viewer_info(var, value);
+
+	return git_default_config(var, value, cb);
+}
+
+static struct cmdnames main_cmds, other_cmds;
+
+void list_common_cmds_help(void)
+{
+	int i, longest = 0;
+
+	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
+		if (longest < strlen(common_cmds[i].name))
+			longest = strlen(common_cmds[i].name);
+	}
+
+	puts("The most commonly used git commands are:");
+	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
+		printf("   %s   ", common_cmds[i].name);
+		mput_char(' ', longest - strlen(common_cmds[i].name));
+		puts(common_cmds[i].help);
+	}
+}
+
+static int is_git_command(const char *s)
+{
+	return is_in_cmdlist(&main_cmds, s) ||
+		is_in_cmdlist(&other_cmds, s);
+}
+
+static const char *prepend(const char *prefix, const char *cmd)
+{
+	size_t pre_len = strlen(prefix);
+	size_t cmd_len = strlen(cmd);
+	char *p = xmalloc(pre_len + cmd_len + 1);
+	memcpy(p, prefix, pre_len);
+	strcpy(p + pre_len, cmd);
+	return p;
+}
+
+static const char *cmd_to_page(const char *git_cmd)
+{
+	if (!git_cmd)
+		return "git";
+	else if (!prefixcmp(git_cmd, "git"))
+		return git_cmd;
+	else if (is_git_command(git_cmd))
+		return prepend("git-", git_cmd);
+	else
+		return prepend("git", git_cmd);
+}
+
+static void setup_man_path(void)
+{
+	struct strbuf new_path = STRBUF_INIT;
+	const char *old_path = getenv("MANPATH");
+
+	/* We should always put ':' after our path. If there is no
+	 * old_path, the ':' at the end will let 'man' to try
+	 * system-wide paths after ours to find the manual page. If
+	 * there is old_path, we need ':' as delimiter. */
+	strbuf_addstr(&new_path, system_path(GIT_MAN_PATH));
+	strbuf_addch(&new_path, ':');
+	if (old_path)
+		strbuf_addstr(&new_path, old_path);
+
+	setenv("MANPATH", new_path.buf, 1);
+
+	strbuf_release(&new_path);
+}
+
+static void exec_viewer(const char *name, const char *page)
+{
+	const char *info = get_man_viewer_info(name);
+
+	if (!strcasecmp(name, "man"))
+		exec_man_man(info, page);
+	else if (!strcasecmp(name, "woman"))
+		exec_woman_emacs(info, page);
+	else if (!strcasecmp(name, "konqueror"))
+		exec_man_konqueror(info, page);
+	else if (info)
+		exec_man_cmd(info, page);
+	else
+		warning("'%s': unknown man viewer.", name);
+}
+
+static void show_man_page(const char *git_cmd)
+{
+	struct man_viewer_list *viewer;
+	const char *page = cmd_to_page(git_cmd);
+	const char *fallback = getenv("GIT_MAN_VIEWER");
+
+	setup_man_path();
+	for (viewer = man_viewer_list; viewer; viewer = viewer->next)
+	{
+		exec_viewer(viewer->name, page); /* will return when unable */
+	}
+	if (fallback)
+		exec_viewer(fallback, page);
+	exec_viewer("man", page);
+	die("no man viewer handled the request");
+}
+
+static void show_info_page(const char *git_cmd)
+{
+	const char *page = cmd_to_page(git_cmd);
+	setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
+	execlp("info", "info", "gitman", page, NULL);
+	die("no info viewer handled the request");
+}
+
+static void get_html_page_path(struct strbuf *page_path, const char *page)
+{
+	struct stat st;
+	const char *html_path = system_path(GIT_HTML_PATH);
+
+	/* Check that we have a git documentation directory. */
+	if (stat(mkpath("%s/git.html", html_path), &st)
+	    || !S_ISREG(st.st_mode))
+		die("'%s': not a documentation directory.", html_path);
+
+	strbuf_init(page_path, 0);
+	strbuf_addf(page_path, "%s/%s.html", html_path, page);
+}
+
+/*
+ * If open_html is not defined in a platform-specific way (see for
+ * example compat/mingw.h), we use the script web--browse to display
+ * HTML.
+ */
+#ifndef open_html
+static void open_html(const char *path)
+{
+	execl_git_cmd("web--browse", "-c", "help.browser", path, NULL);
+}
+#endif
+
+static void show_html_page(const char *git_cmd)
+{
+	const char *page = cmd_to_page(git_cmd);
+	struct strbuf page_path; /* it leaks but we exec bellow */
+
+	get_html_page_path(&page_path, page);
+
+	open_html(page_path.buf);
+}
+
+int cmd_help(int argc, const char **argv, const char *prefix)
+{
+	int nongit;
+	const char *alias;
+	enum help_format parsed_help_format;
+	load_command_list("git-", &main_cmds, &other_cmds);
+
+	argc = parse_options(argc, argv, prefix, builtin_help_options,
+			builtin_help_usage, 0);
+	parsed_help_format = help_format;
+
+	if (show_all) {
+		printf("usage: %s\n\n", git_usage_string);
+		list_commands("git commands", &main_cmds, &other_cmds);
+		printf("%s\n", git_more_info_string);
+		return 0;
+	}
+
+	if (!argv[0]) {
+		printf("usage: %s\n\n", git_usage_string);
+		list_common_cmds_help();
+		printf("\n%s\n", git_more_info_string);
+		return 0;
+	}
+
+	setup_git_directory_gently(&nongit);
+	git_config(git_help_config, NULL);
+
+	if (parsed_help_format != HELP_FORMAT_NONE)
+		help_format = parsed_help_format;
+
+	alias = alias_lookup(argv[0]);
+	if (alias && !is_git_command(argv[0])) {
+		printf("`git %s' is aliased to `%s'\n", argv[0], alias);
+		return 0;
+	}
+
+	switch (help_format) {
+	case HELP_FORMAT_NONE:
+	case HELP_FORMAT_MAN:
+		show_man_page(argv[0]);
+		break;
+	case HELP_FORMAT_INFO:
+		show_info_page(argv[0]);
+		break;
+	case HELP_FORMAT_WEB:
+		show_html_page(argv[0]);
+		break;
+	}
+
+	return 0;
+}
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
new file mode 100644
index 0000000..b4cf8c5
--- /dev/null
+++ b/builtin/index-pack.c
@@ -0,0 +1,1045 @@
+#include "cache.h"
+#include "delta.h"
+#include "pack.h"
+#include "csum-file.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree.h"
+#include "progress.h"
+#include "fsck.h"
+#include "exec_cmd.h"
+
+static const char index_pack_usage[] =
+"git index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] [--strict] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
+
+struct object_entry
+{
+	struct pack_idx_entry idx;
+	unsigned long size;
+	unsigned int hdr_size;
+	enum object_type type;
+	enum object_type real_type;
+};
+
+union delta_base {
+	unsigned char sha1[20];
+	off_t offset;
+};
+
+struct base_data {
+	struct base_data *base;
+	struct base_data *child;
+	struct object_entry *obj;
+	void *data;
+	unsigned long size;
+};
+
+/*
+ * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
+ * to memcmp() only the first 20 bytes.
+ */
+#define UNION_BASE_SZ	20
+
+#define FLAG_LINK (1u<<20)
+#define FLAG_CHECKED (1u<<21)
+
+struct delta_entry
+{
+	union delta_base base;
+	int obj_no;
+};
+
+static struct object_entry *objects;
+static struct delta_entry *deltas;
+static struct base_data *base_cache;
+static size_t base_cache_used;
+static int nr_objects;
+static int nr_deltas;
+static int nr_resolved_deltas;
+
+static int from_stdin;
+static int strict;
+static int verbose;
+
+static struct progress *progress;
+
+/* We always read in 4kB chunks. */
+static unsigned char input_buffer[4096];
+static unsigned int input_offset, input_len;
+static off_t consumed_bytes;
+static git_SHA_CTX input_ctx;
+static uint32_t input_crc32;
+static int input_fd, output_fd, pack_fd;
+
+static int mark_link(struct object *obj, int type, void *data)
+{
+	if (!obj)
+		return -1;
+
+	if (type != OBJ_ANY && obj->type != type)
+		die("object type mismatch at %s", sha1_to_hex(obj->sha1));
+
+	obj->flags |= FLAG_LINK;
+	return 0;
+}
+
+/* The content of each linked object must have been checked
+   or it must be already present in the object database */
+static void check_object(struct object *obj)
+{
+	if (!obj)
+		return;
+
+	if (!(obj->flags & FLAG_LINK))
+		return;
+
+	if (!(obj->flags & FLAG_CHECKED)) {
+		unsigned long size;
+		int type = sha1_object_info(obj->sha1, &size);
+		if (type != obj->type || type <= 0)
+			die("object of unexpected type");
+		obj->flags |= FLAG_CHECKED;
+		return;
+	}
+}
+
+static void check_objects(void)
+{
+	unsigned i, max;
+
+	max = get_max_object_index();
+	for (i = 0; i < max; i++)
+		check_object(get_indexed_object(i));
+}
+
+
+/* Discard current buffer used content. */
+static void flush(void)
+{
+	if (input_offset) {
+		if (output_fd >= 0)
+			write_or_die(output_fd, input_buffer, input_offset);
+		git_SHA1_Update(&input_ctx, input_buffer, input_offset);
+		memmove(input_buffer, input_buffer + input_offset, input_len);
+		input_offset = 0;
+	}
+}
+
+/*
+ * Make sure at least "min" bytes are available in the buffer, and
+ * return the pointer to the buffer.
+ */
+static void *fill(int min)
+{
+	if (min <= input_len)
+		return input_buffer + input_offset;
+	if (min > sizeof(input_buffer))
+		die("cannot fill %d bytes", min);
+	flush();
+	do {
+		ssize_t ret = xread(input_fd, input_buffer + input_len,
+				sizeof(input_buffer) - input_len);
+		if (ret <= 0) {
+			if (!ret)
+				die("early EOF");
+			die_errno("read error on input");
+		}
+		input_len += ret;
+		if (from_stdin)
+			display_throughput(progress, consumed_bytes + input_len);
+	} while (input_len < min);
+	return input_buffer;
+}
+
+static void use(int bytes)
+{
+	if (bytes > input_len)
+		die("used more bytes than were available");
+	input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
+	input_len -= bytes;
+	input_offset += bytes;
+
+	/* make sure off_t is sufficiently large not to wrap */
+	if (consumed_bytes > consumed_bytes + bytes)
+		die("pack too large for current definition of off_t");
+	consumed_bytes += bytes;
+}
+
+static const char *open_pack_file(const char *pack_name)
+{
+	if (from_stdin) {
+		input_fd = 0;
+		if (!pack_name) {
+			static char tmpfile[PATH_MAX];
+			output_fd = odb_mkstemp(tmpfile, sizeof(tmpfile),
+						"pack/tmp_pack_XXXXXX");
+			pack_name = xstrdup(tmpfile);
+		} else
+			output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
+		if (output_fd < 0)
+			die_errno("unable to create '%s'", pack_name);
+		pack_fd = output_fd;
+	} else {
+		input_fd = open(pack_name, O_RDONLY);
+		if (input_fd < 0)
+			die_errno("cannot open packfile '%s'", pack_name);
+		output_fd = -1;
+		pack_fd = input_fd;
+	}
+	git_SHA1_Init(&input_ctx);
+	return pack_name;
+}
+
+static void parse_pack_header(void)
+{
+	struct pack_header *hdr = fill(sizeof(struct pack_header));
+
+	/* Header consistency check */
+	if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
+		die("pack signature mismatch");
+	if (!pack_version_ok(hdr->hdr_version))
+		die("pack version %"PRIu32" unsupported",
+			ntohl(hdr->hdr_version));
+
+	nr_objects = ntohl(hdr->hdr_entries);
+	use(sizeof(struct pack_header));
+}
+
+static NORETURN void bad_object(unsigned long offset, const char *format,
+		       ...) __attribute__((format (printf, 2, 3)));
+
+static void bad_object(unsigned long offset, const char *format, ...)
+{
+	va_list params;
+	char buf[1024];
+
+	va_start(params, format);
+	vsnprintf(buf, sizeof(buf), format, params);
+	va_end(params);
+	die("pack has bad object at offset %lu: %s", offset, buf);
+}
+
+static void free_base_data(struct base_data *c)
+{
+	if (c->data) {
+		free(c->data);
+		c->data = NULL;
+		base_cache_used -= c->size;
+	}
+}
+
+static void prune_base_data(struct base_data *retain)
+{
+	struct base_data *b;
+	for (b = base_cache;
+	     base_cache_used > delta_base_cache_limit && b;
+	     b = b->child) {
+		if (b->data && b != retain)
+			free_base_data(b);
+	}
+}
+
+static void link_base_data(struct base_data *base, struct base_data *c)
+{
+	if (base)
+		base->child = c;
+	else
+		base_cache = c;
+
+	c->base = base;
+	c->child = NULL;
+	if (c->data)
+		base_cache_used += c->size;
+	prune_base_data(c);
+}
+
+static void unlink_base_data(struct base_data *c)
+{
+	struct base_data *base = c->base;
+	if (base)
+		base->child = NULL;
+	else
+		base_cache = NULL;
+	free_base_data(c);
+}
+
+static void *unpack_entry_data(unsigned long offset, unsigned long size)
+{
+	z_stream stream;
+	void *buf = xmalloc(size);
+
+	memset(&stream, 0, sizeof(stream));
+	stream.next_out = buf;
+	stream.avail_out = size;
+	stream.next_in = fill(1);
+	stream.avail_in = input_len;
+	git_inflate_init(&stream);
+
+	for (;;) {
+		int ret = git_inflate(&stream, 0);
+		use(input_len - stream.avail_in);
+		if (stream.total_out == size && ret == Z_STREAM_END)
+			break;
+		if (ret != Z_OK)
+			bad_object(offset, "inflate returned %d", ret);
+		stream.next_in = fill(1);
+		stream.avail_in = input_len;
+	}
+	git_inflate_end(&stream);
+	return buf;
+}
+
+static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
+{
+	unsigned char *p;
+	unsigned long size, c;
+	off_t base_offset;
+	unsigned shift;
+	void *data;
+
+	obj->idx.offset = consumed_bytes;
+	input_crc32 = crc32(0, Z_NULL, 0);
+
+	p = fill(1);
+	c = *p;
+	use(1);
+	obj->type = (c >> 4) & 7;
+	size = (c & 15);
+	shift = 4;
+	while (c & 0x80) {
+		p = fill(1);
+		c = *p;
+		use(1);
+		size += (c & 0x7f) << shift;
+		shift += 7;
+	}
+	obj->size = size;
+
+	switch (obj->type) {
+	case OBJ_REF_DELTA:
+		hashcpy(delta_base->sha1, fill(20));
+		use(20);
+		break;
+	case OBJ_OFS_DELTA:
+		memset(delta_base, 0, sizeof(*delta_base));
+		p = fill(1);
+		c = *p;
+		use(1);
+		base_offset = c & 127;
+		while (c & 128) {
+			base_offset += 1;
+			if (!base_offset || MSB(base_offset, 7))
+				bad_object(obj->idx.offset, "offset value overflow for delta base object");
+			p = fill(1);
+			c = *p;
+			use(1);
+			base_offset = (base_offset << 7) + (c & 127);
+		}
+		delta_base->offset = obj->idx.offset - base_offset;
+		if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
+			bad_object(obj->idx.offset, "delta base offset is out of bound");
+		break;
+	case OBJ_COMMIT:
+	case OBJ_TREE:
+	case OBJ_BLOB:
+	case OBJ_TAG:
+		break;
+	default:
+		bad_object(obj->idx.offset, "unknown object type %d", obj->type);
+	}
+	obj->hdr_size = consumed_bytes - obj->idx.offset;
+
+	data = unpack_entry_data(obj->idx.offset, obj->size);
+	obj->idx.crc32 = input_crc32;
+	return data;
+}
+
+static void *get_data_from_pack(struct object_entry *obj)
+{
+	off_t from = obj[0].idx.offset + obj[0].hdr_size;
+	unsigned long len = obj[1].idx.offset - from;
+	unsigned long rdy = 0;
+	unsigned char *src, *data;
+	z_stream stream;
+	int st;
+
+	src = xmalloc(len);
+	data = src;
+	do {
+		ssize_t n = pread(pack_fd, data + rdy, len - rdy, from + rdy);
+		if (n < 0)
+			die_errno("cannot pread pack file");
+		if (!n)
+			die("premature end of pack file, %lu bytes missing",
+			    len - rdy);
+		rdy += n;
+	} while (rdy < len);
+	data = xmalloc(obj->size);
+	memset(&stream, 0, sizeof(stream));
+	stream.next_out = data;
+	stream.avail_out = obj->size;
+	stream.next_in = src;
+	stream.avail_in = len;
+	git_inflate_init(&stream);
+	while ((st = git_inflate(&stream, Z_FINISH)) == Z_OK);
+	git_inflate_end(&stream);
+	if (st != Z_STREAM_END || stream.total_out != obj->size)
+		die("serious inflate inconsistency");
+	free(src);
+	return data;
+}
+
+static int find_delta(const union delta_base *base)
+{
+	int first = 0, last = nr_deltas;
+
+        while (first < last) {
+                int next = (first + last) / 2;
+                struct delta_entry *delta = &deltas[next];
+                int cmp;
+
+                cmp = memcmp(base, &delta->base, UNION_BASE_SZ);
+                if (!cmp)
+                        return next;
+                if (cmp < 0) {
+                        last = next;
+                        continue;
+                }
+                first = next+1;
+        }
+        return -first-1;
+}
+
+static void find_delta_children(const union delta_base *base,
+				int *first_index, int *last_index)
+{
+	int first = find_delta(base);
+	int last = first;
+	int end = nr_deltas - 1;
+
+	if (first < 0) {
+		*first_index = 0;
+		*last_index = -1;
+		return;
+	}
+	while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
+		--first;
+	while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
+		++last;
+	*first_index = first;
+	*last_index = last;
+}
+
+static void sha1_object(const void *data, unsigned long size,
+			enum object_type type, unsigned char *sha1)
+{
+	hash_sha1_file(data, size, typename(type), sha1);
+	if (has_sha1_file(sha1)) {
+		void *has_data;
+		enum object_type has_type;
+		unsigned long has_size;
+		has_data = read_sha1_file(sha1, &has_type, &has_size);
+		if (!has_data)
+			die("cannot read existing object %s", sha1_to_hex(sha1));
+		if (size != has_size || type != has_type ||
+		    memcmp(data, has_data, size) != 0)
+			die("SHA1 COLLISION FOUND WITH %s !", sha1_to_hex(sha1));
+		free(has_data);
+	}
+	if (strict) {
+		if (type == OBJ_BLOB) {
+			struct blob *blob = lookup_blob(sha1);
+			if (blob)
+				blob->object.flags |= FLAG_CHECKED;
+			else
+				die("invalid blob object %s", sha1_to_hex(sha1));
+		} else {
+			struct object *obj;
+			int eaten;
+			void *buf = (void *) data;
+
+			/*
+			 * we do not need to free the memory here, as the
+			 * buf is deleted by the caller.
+			 */
+			obj = parse_object_buffer(sha1, type, size, buf, &eaten);
+			if (!obj)
+				die("invalid %s", typename(type));
+			if (fsck_object(obj, 1, fsck_error_function))
+				die("Error in object");
+			if (fsck_walk(obj, mark_link, NULL))
+				die("Not all child objects of %s are reachable", sha1_to_hex(obj->sha1));
+
+			if (obj->type == OBJ_TREE) {
+				struct tree *item = (struct tree *) obj;
+				item->buffer = NULL;
+			}
+			if (obj->type == OBJ_COMMIT) {
+				struct commit *commit = (struct commit *) obj;
+				commit->buffer = NULL;
+			}
+			obj->flags |= FLAG_CHECKED;
+		}
+	}
+}
+
+static void *get_base_data(struct base_data *c)
+{
+	if (!c->data) {
+		struct object_entry *obj = c->obj;
+
+		if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
+			void *base = get_base_data(c->base);
+			void *raw = get_data_from_pack(obj);
+			c->data = patch_delta(
+				base, c->base->size,
+				raw, obj->size,
+				&c->size);
+			free(raw);
+			if (!c->data)
+				bad_object(obj->idx.offset, "failed to apply delta");
+		} else {
+			c->data = get_data_from_pack(obj);
+			c->size = obj->size;
+		}
+
+		base_cache_used += c->size;
+		prune_base_data(c);
+	}
+	return c->data;
+}
+
+static void resolve_delta(struct object_entry *delta_obj,
+			  struct base_data *base, struct base_data *result)
+{
+	void *base_data, *delta_data;
+
+	delta_obj->real_type = base->obj->real_type;
+	delta_data = get_data_from_pack(delta_obj);
+	base_data = get_base_data(base);
+	result->obj = delta_obj;
+	result->data = patch_delta(base_data, base->size,
+				   delta_data, delta_obj->size, &result->size);
+	free(delta_data);
+	if (!result->data)
+		bad_object(delta_obj->idx.offset, "failed to apply delta");
+	sha1_object(result->data, result->size, delta_obj->real_type,
+		    delta_obj->idx.sha1);
+	nr_resolved_deltas++;
+}
+
+static void find_unresolved_deltas(struct base_data *base,
+				   struct base_data *prev_base)
+{
+	int i, ref_first, ref_last, ofs_first, ofs_last;
+
+	/*
+	 * This is a recursive function. Those brackets should help reducing
+	 * stack usage by limiting the scope of the delta_base union.
+	 */
+	{
+		union delta_base base_spec;
+
+		hashcpy(base_spec.sha1, base->obj->idx.sha1);
+		find_delta_children(&base_spec, &ref_first, &ref_last);
+
+		memset(&base_spec, 0, sizeof(base_spec));
+		base_spec.offset = base->obj->idx.offset;
+		find_delta_children(&base_spec, &ofs_first, &ofs_last);
+	}
+
+	if (ref_last == -1 && ofs_last == -1) {
+		free(base->data);
+		return;
+	}
+
+	link_base_data(prev_base, base);
+
+	for (i = ref_first; i <= ref_last; i++) {
+		struct object_entry *child = objects + deltas[i].obj_no;
+		if (child->real_type == OBJ_REF_DELTA) {
+			struct base_data result;
+			resolve_delta(child, base, &result);
+			if (i == ref_last && ofs_last == -1)
+				free_base_data(base);
+			find_unresolved_deltas(&result, base);
+		}
+	}
+
+	for (i = ofs_first; i <= ofs_last; i++) {
+		struct object_entry *child = objects + deltas[i].obj_no;
+		if (child->real_type == OBJ_OFS_DELTA) {
+			struct base_data result;
+			resolve_delta(child, base, &result);
+			if (i == ofs_last)
+				free_base_data(base);
+			find_unresolved_deltas(&result, base);
+		}
+	}
+
+	unlink_base_data(base);
+}
+
+static int compare_delta_entry(const void *a, const void *b)
+{
+	const struct delta_entry *delta_a = a;
+	const struct delta_entry *delta_b = b;
+	return memcmp(&delta_a->base, &delta_b->base, UNION_BASE_SZ);
+}
+
+/* Parse all objects and return the pack content SHA1 hash */
+static void parse_pack_objects(unsigned char *sha1)
+{
+	int i;
+	struct delta_entry *delta = deltas;
+	struct stat st;
+
+	/*
+	 * First pass:
+	 * - find locations of all objects;
+	 * - calculate SHA1 of all non-delta objects;
+	 * - remember base (SHA1 or offset) for all deltas.
+	 */
+	if (verbose)
+		progress = start_progress(
+				from_stdin ? "Receiving objects" : "Indexing objects",
+				nr_objects);
+	for (i = 0; i < nr_objects; i++) {
+		struct object_entry *obj = &objects[i];
+		void *data = unpack_raw_entry(obj, &delta->base);
+		obj->real_type = obj->type;
+		if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
+			nr_deltas++;
+			delta->obj_no = i;
+			delta++;
+		} else
+			sha1_object(data, obj->size, obj->type, obj->idx.sha1);
+		free(data);
+		display_progress(progress, i+1);
+	}
+	objects[i].idx.offset = consumed_bytes;
+	stop_progress(&progress);
+
+	/* Check pack integrity */
+	flush();
+	git_SHA1_Final(sha1, &input_ctx);
+	if (hashcmp(fill(20), sha1))
+		die("pack is corrupted (SHA1 mismatch)");
+	use(20);
+
+	/* If input_fd is a file, we should have reached its end now. */
+	if (fstat(input_fd, &st))
+		die_errno("cannot fstat packfile");
+	if (S_ISREG(st.st_mode) &&
+			lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
+		die("pack has junk at the end");
+
+	if (!nr_deltas)
+		return;
+
+	/* Sort deltas by base SHA1/offset for fast searching */
+	qsort(deltas, nr_deltas, sizeof(struct delta_entry),
+	      compare_delta_entry);
+
+	/*
+	 * Second pass:
+	 * - for all non-delta objects, look if it is used as a base for
+	 *   deltas;
+	 * - if used as a base, uncompress the object and apply all deltas,
+	 *   recursively checking if the resulting object is used as a base
+	 *   for some more deltas.
+	 */
+	if (verbose)
+		progress = start_progress("Resolving deltas", nr_deltas);
+	for (i = 0; i < nr_objects; i++) {
+		struct object_entry *obj = &objects[i];
+		struct base_data base_obj;
+
+		if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA)
+			continue;
+		base_obj.obj = obj;
+		base_obj.data = NULL;
+		find_unresolved_deltas(&base_obj, NULL);
+		display_progress(progress, nr_resolved_deltas);
+	}
+}
+
+static int write_compressed(struct sha1file *f, void *in, unsigned int size)
+{
+	z_stream stream;
+	unsigned long maxsize;
+	void *out;
+
+	memset(&stream, 0, sizeof(stream));
+	deflateInit(&stream, zlib_compression_level);
+	maxsize = deflateBound(&stream, size);
+	out = xmalloc(maxsize);
+
+	/* Compress it */
+	stream.next_in = in;
+	stream.avail_in = size;
+	stream.next_out = out;
+	stream.avail_out = maxsize;
+	while (deflate(&stream, Z_FINISH) == Z_OK);
+	deflateEnd(&stream);
+
+	size = stream.total_out;
+	sha1write(f, out, size);
+	free(out);
+	return size;
+}
+
+static struct object_entry *append_obj_to_pack(struct sha1file *f,
+			       const unsigned char *sha1, void *buf,
+			       unsigned long size, enum object_type type)
+{
+	struct object_entry *obj = &objects[nr_objects++];
+	unsigned char header[10];
+	unsigned long s = size;
+	int n = 0;
+	unsigned char c = (type << 4) | (s & 15);
+	s >>= 4;
+	while (s) {
+		header[n++] = c | 0x80;
+		c = s & 0x7f;
+		s >>= 7;
+	}
+	header[n++] = c;
+	crc32_begin(f);
+	sha1write(f, header, n);
+	obj[0].size = size;
+	obj[0].hdr_size = n;
+	obj[0].type = type;
+	obj[0].real_type = type;
+	obj[1].idx.offset = obj[0].idx.offset + n;
+	obj[1].idx.offset += write_compressed(f, buf, size);
+	obj[0].idx.crc32 = crc32_end(f);
+	sha1flush(f);
+	hashcpy(obj->idx.sha1, sha1);
+	return obj;
+}
+
+static int delta_pos_compare(const void *_a, const void *_b)
+{
+	struct delta_entry *a = *(struct delta_entry **)_a;
+	struct delta_entry *b = *(struct delta_entry **)_b;
+	return a->obj_no - b->obj_no;
+}
+
+static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
+{
+	struct delta_entry **sorted_by_pos;
+	int i, n = 0;
+
+	/*
+	 * Since many unresolved deltas may well be themselves base objects
+	 * for more unresolved deltas, we really want to include the
+	 * smallest number of base objects that would cover as much delta
+	 * as possible by picking the
+	 * trunc deltas first, allowing for other deltas to resolve without
+	 * additional base objects.  Since most base objects are to be found
+	 * before deltas depending on them, a good heuristic is to start
+	 * resolving deltas in the same order as their position in the pack.
+	 */
+	sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
+	for (i = 0; i < nr_deltas; i++) {
+		if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
+			continue;
+		sorted_by_pos[n++] = &deltas[i];
+	}
+	qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
+
+	for (i = 0; i < n; i++) {
+		struct delta_entry *d = sorted_by_pos[i];
+		enum object_type type;
+		struct base_data base_obj;
+
+		if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
+			continue;
+		base_obj.data = read_sha1_file(d->base.sha1, &type, &base_obj.size);
+		if (!base_obj.data)
+			continue;
+
+		if (check_sha1_signature(d->base.sha1, base_obj.data,
+				base_obj.size, typename(type)))
+			die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
+		base_obj.obj = append_obj_to_pack(f, d->base.sha1,
+					base_obj.data, base_obj.size, type);
+		find_unresolved_deltas(&base_obj, NULL);
+		display_progress(progress, nr_resolved_deltas);
+	}
+	free(sorted_by_pos);
+}
+
+static void final(const char *final_pack_name, const char *curr_pack_name,
+		  const char *final_index_name, const char *curr_index_name,
+		  const char *keep_name, const char *keep_msg,
+		  unsigned char *sha1)
+{
+	const char *report = "pack";
+	char name[PATH_MAX];
+	int err;
+
+	if (!from_stdin) {
+		close(input_fd);
+	} else {
+		fsync_or_die(output_fd, curr_pack_name);
+		err = close(output_fd);
+		if (err)
+			die_errno("error while closing pack file");
+	}
+
+	if (keep_msg) {
+		int keep_fd, keep_msg_len = strlen(keep_msg);
+
+		if (!keep_name)
+			keep_fd = odb_pack_keep(name, sizeof(name), sha1);
+		else
+			keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
+
+		if (keep_fd < 0) {
+			if (errno != EEXIST)
+				die_errno("cannot write keep file '%s'",
+					  keep_name);
+		} else {
+			if (keep_msg_len > 0) {
+				write_or_die(keep_fd, keep_msg, keep_msg_len);
+				write_or_die(keep_fd, "\n", 1);
+			}
+			if (close(keep_fd) != 0)
+				die_errno("cannot close written keep file '%s'",
+				    keep_name);
+			report = "keep";
+		}
+	}
+
+	if (final_pack_name != curr_pack_name) {
+		if (!final_pack_name) {
+			snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
+				 get_object_directory(), sha1_to_hex(sha1));
+			final_pack_name = name;
+		}
+		if (move_temp_to_file(curr_pack_name, final_pack_name))
+			die("cannot store pack file");
+	} else if (from_stdin)
+		chmod(final_pack_name, 0444);
+
+	if (final_index_name != curr_index_name) {
+		if (!final_index_name) {
+			snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
+				 get_object_directory(), sha1_to_hex(sha1));
+			final_index_name = name;
+		}
+		if (move_temp_to_file(curr_index_name, final_index_name))
+			die("cannot store index file");
+	} else
+		chmod(final_index_name, 0444);
+
+	if (!from_stdin) {
+		printf("%s\n", sha1_to_hex(sha1));
+	} else {
+		char buf[48];
+		int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
+				   report, sha1_to_hex(sha1));
+		write_or_die(1, buf, len);
+
+		/*
+		 * Let's just mimic git-unpack-objects here and write
+		 * the last part of the input buffer to stdout.
+		 */
+		while (input_len) {
+			err = xwrite(1, input_buffer + input_offset, input_len);
+			if (err <= 0)
+				break;
+			input_len -= err;
+			input_offset += err;
+		}
+	}
+}
+
+static int git_index_pack_config(const char *k, const char *v, void *cb)
+{
+	if (!strcmp(k, "pack.indexversion")) {
+		pack_idx_default_version = git_config_int(k, v);
+		if (pack_idx_default_version > 2)
+			die("bad pack.indexversion=%"PRIu32,
+				pack_idx_default_version);
+		return 0;
+	}
+	return git_default_config(k, v, cb);
+}
+
+int cmd_index_pack(int argc, const char **argv, const char *prefix)
+{
+	int i, fix_thin_pack = 0;
+	const char *curr_pack, *curr_index;
+	const char *index_name = NULL, *pack_name = NULL;
+	const char *keep_name = NULL, *keep_msg = NULL;
+	char *index_name_buf = NULL, *keep_name_buf = NULL;
+	struct pack_idx_entry **idx_objects;
+	unsigned char pack_sha1[20];
+
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage(index_pack_usage);
+
+	/*
+	 * We wish to read the repository's config file if any, and
+	 * for that it is necessary to call setup_git_directory_gently().
+	 * However if the cwd was inside .git/objects/pack/ then we need
+	 * to go back there or all the pack name arguments will be wrong.
+	 * And in that case we cannot rely on any prefix returned by
+	 * setup_git_directory_gently() either.
+	 */
+	{
+		char cwd[PATH_MAX+1];
+		int nongit;
+
+		if (!getcwd(cwd, sizeof(cwd)-1))
+			die("Unable to get current working directory");
+		setup_git_directory_gently(&nongit);
+		git_config(git_index_pack_config, NULL);
+		if (chdir(cwd))
+			die("Cannot come back to cwd");
+	}
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (*arg == '-') {
+			if (!strcmp(arg, "--stdin")) {
+				from_stdin = 1;
+			} else if (!strcmp(arg, "--fix-thin")) {
+				fix_thin_pack = 1;
+			} else if (!strcmp(arg, "--strict")) {
+				strict = 1;
+			} else if (!strcmp(arg, "--keep")) {
+				keep_msg = "";
+			} else if (!prefixcmp(arg, "--keep=")) {
+				keep_msg = arg + 7;
+			} else if (!prefixcmp(arg, "--pack_header=")) {
+				struct pack_header *hdr;
+				char *c;
+
+				hdr = (struct pack_header *)input_buffer;
+				hdr->hdr_signature = htonl(PACK_SIGNATURE);
+				hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
+				if (*c != ',')
+					die("bad %s", arg);
+				hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
+				if (*c)
+					die("bad %s", arg);
+				input_len = sizeof(*hdr);
+			} else if (!strcmp(arg, "-v")) {
+				verbose = 1;
+			} else if (!strcmp(arg, "-o")) {
+				if (index_name || (i+1) >= argc)
+					usage(index_pack_usage);
+				index_name = argv[++i];
+			} else if (!prefixcmp(arg, "--index-version=")) {
+				char *c;
+				pack_idx_default_version = strtoul(arg + 16, &c, 10);
+				if (pack_idx_default_version > 2)
+					die("bad %s", arg);
+				if (*c == ',')
+					pack_idx_off32_limit = strtoul(c+1, &c, 0);
+				if (*c || pack_idx_off32_limit & 0x80000000)
+					die("bad %s", arg);
+			} else
+				usage(index_pack_usage);
+			continue;
+		}
+
+		if (pack_name)
+			usage(index_pack_usage);
+		pack_name = arg;
+	}
+
+	if (!pack_name && !from_stdin)
+		usage(index_pack_usage);
+	if (fix_thin_pack && !from_stdin)
+		die("--fix-thin cannot be used without --stdin");
+	if (!index_name && pack_name) {
+		int len = strlen(pack_name);
+		if (!has_extension(pack_name, ".pack"))
+			die("packfile name '%s' does not end with '.pack'",
+			    pack_name);
+		index_name_buf = xmalloc(len);
+		memcpy(index_name_buf, pack_name, len - 5);
+		strcpy(index_name_buf + len - 5, ".idx");
+		index_name = index_name_buf;
+	}
+	if (keep_msg && !keep_name && pack_name) {
+		int len = strlen(pack_name);
+		if (!has_extension(pack_name, ".pack"))
+			die("packfile name '%s' does not end with '.pack'",
+			    pack_name);
+		keep_name_buf = xmalloc(len);
+		memcpy(keep_name_buf, pack_name, len - 5);
+		strcpy(keep_name_buf + len - 5, ".keep");
+		keep_name = keep_name_buf;
+	}
+
+	curr_pack = open_pack_file(pack_name);
+	parse_pack_header();
+	objects = xmalloc((nr_objects + 1) * sizeof(struct object_entry));
+	deltas = xmalloc(nr_objects * sizeof(struct delta_entry));
+	parse_pack_objects(pack_sha1);
+	if (nr_deltas == nr_resolved_deltas) {
+		stop_progress(&progress);
+		/* Flush remaining pack final 20-byte SHA1. */
+		flush();
+	} else {
+		if (fix_thin_pack) {
+			struct sha1file *f;
+			unsigned char read_sha1[20], tail_sha1[20];
+			char msg[48];
+			int nr_unresolved = nr_deltas - nr_resolved_deltas;
+			int nr_objects_initial = nr_objects;
+			if (nr_unresolved <= 0)
+				die("confusion beyond insanity");
+			objects = xrealloc(objects,
+					   (nr_objects + nr_unresolved + 1)
+					   * sizeof(*objects));
+			f = sha1fd(output_fd, curr_pack);
+			fix_unresolved_deltas(f, nr_unresolved);
+			sprintf(msg, "completed with %d local objects",
+				nr_objects - nr_objects_initial);
+			stop_progress_msg(&progress, msg);
+			sha1close(f, tail_sha1, 0);
+			hashcpy(read_sha1, pack_sha1);
+			fixup_pack_header_footer(output_fd, pack_sha1,
+						 curr_pack, nr_objects,
+						 read_sha1, consumed_bytes-20);
+			if (hashcmp(read_sha1, tail_sha1) != 0)
+				die("Unexpected tail checksum for %s "
+				    "(disk corruption?)", curr_pack);
+		}
+		if (nr_deltas != nr_resolved_deltas)
+			die("pack has %d unresolved deltas",
+			    nr_deltas - nr_resolved_deltas);
+	}
+	free(deltas);
+	if (strict)
+		check_objects();
+
+	idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
+	for (i = 0; i < nr_objects; i++)
+		idx_objects[i] = &objects[i].idx;
+	curr_index = write_idx_file(index_name, idx_objects, nr_objects, pack_sha1);
+	free(idx_objects);
+
+	final(pack_name, curr_pack,
+		index_name, curr_index,
+		keep_name, keep_msg,
+		pack_sha1);
+	free(objects);
+	free(index_name_buf);
+	free(keep_name_buf);
+	if (pack_name == NULL)
+		free((void *) curr_pack);
+	if (index_name == NULL)
+		free((void *) curr_index);
+
+	return 0;
+}
diff --git a/builtin/init-db.c b/builtin/init-db.c
new file mode 100644
index 0000000..aae7a4d
--- /dev/null
+++ b/builtin/init-db.c
@@ -0,0 +1,501 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "parse-options.h"
+
+#ifndef DEFAULT_GIT_TEMPLATE_DIR
+#define DEFAULT_GIT_TEMPLATE_DIR "/usr/share/git-core/templates"
+#endif
+
+#ifdef NO_TRUSTABLE_FILEMODE
+#define TEST_FILEMODE 0
+#else
+#define TEST_FILEMODE 1
+#endif
+
+static int init_is_bare_repository = 0;
+static int init_shared_repository = -1;
+
+static void safe_create_dir(const char *dir, int share)
+{
+	if (mkdir(dir, 0777) < 0) {
+		if (errno != EEXIST) {
+			perror(dir);
+			exit(1);
+		}
+	}
+	else if (share && adjust_shared_perm(dir))
+		die("Could not make %s writable by group", dir);
+}
+
+static void copy_templates_1(char *path, int baselen,
+			     char *template, int template_baselen,
+			     DIR *dir)
+{
+	struct dirent *de;
+
+	/* Note: if ".git/hooks" file exists in the repository being
+	 * re-initialized, /etc/core-git/templates/hooks/update would
+	 * cause "git init" to fail here.  I think this is sane but
+	 * it means that the set of templates we ship by default, along
+	 * with the way the namespace under .git/ is organized, should
+	 * be really carefully chosen.
+	 */
+	safe_create_dir(path, 1);
+	while ((de = readdir(dir)) != NULL) {
+		struct stat st_git, st_template;
+		int namelen;
+		int exists = 0;
+
+		if (de->d_name[0] == '.')
+			continue;
+		namelen = strlen(de->d_name);
+		if ((PATH_MAX <= baselen + namelen) ||
+		    (PATH_MAX <= template_baselen + namelen))
+			die("insanely long template name %s", de->d_name);
+		memcpy(path + baselen, de->d_name, namelen+1);
+		memcpy(template + template_baselen, de->d_name, namelen+1);
+		if (lstat(path, &st_git)) {
+			if (errno != ENOENT)
+				die_errno("cannot stat '%s'", path);
+		}
+		else
+			exists = 1;
+
+		if (lstat(template, &st_template))
+			die_errno("cannot stat template '%s'", template);
+
+		if (S_ISDIR(st_template.st_mode)) {
+			DIR *subdir = opendir(template);
+			int baselen_sub = baselen + namelen;
+			int template_baselen_sub = template_baselen + namelen;
+			if (!subdir)
+				die_errno("cannot opendir '%s'", template);
+			path[baselen_sub++] =
+				template[template_baselen_sub++] = '/';
+			path[baselen_sub] =
+				template[template_baselen_sub] = 0;
+			copy_templates_1(path, baselen_sub,
+					 template, template_baselen_sub,
+					 subdir);
+			closedir(subdir);
+		}
+		else if (exists)
+			continue;
+		else if (S_ISLNK(st_template.st_mode)) {
+			char lnk[256];
+			int len;
+			len = readlink(template, lnk, sizeof(lnk));
+			if (len < 0)
+				die_errno("cannot readlink '%s'", template);
+			if (sizeof(lnk) <= len)
+				die("insanely long symlink %s", template);
+			lnk[len] = 0;
+			if (symlink(lnk, path))
+				die_errno("cannot symlink '%s' '%s'", lnk, path);
+		}
+		else if (S_ISREG(st_template.st_mode)) {
+			if (copy_file(path, template, st_template.st_mode))
+				die_errno("cannot copy '%s' to '%s'", template,
+					  path);
+		}
+		else
+			error("ignoring template %s", template);
+	}
+}
+
+static void copy_templates(const char *template_dir)
+{
+	char path[PATH_MAX];
+	char template_path[PATH_MAX];
+	int template_len;
+	DIR *dir;
+	const char *git_dir = get_git_dir();
+	int len = strlen(git_dir);
+
+	if (!template_dir)
+		template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
+	if (!template_dir)
+		template_dir = system_path(DEFAULT_GIT_TEMPLATE_DIR);
+	if (!template_dir[0])
+		return;
+	template_len = strlen(template_dir);
+	if (PATH_MAX <= (template_len+strlen("/config")))
+		die("insanely long template path %s", template_dir);
+	strcpy(template_path, template_dir);
+	if (template_path[template_len-1] != '/') {
+		template_path[template_len++] = '/';
+		template_path[template_len] = 0;
+	}
+	dir = opendir(template_path);
+	if (!dir) {
+		warning("templates not found %s", template_dir);
+		return;
+	}
+
+	/* Make sure that template is from the correct vintage */
+	strcpy(template_path + template_len, "config");
+	repository_format_version = 0;
+	git_config_from_file(check_repository_format_version,
+			     template_path, NULL);
+	template_path[template_len] = 0;
+
+	if (repository_format_version &&
+	    repository_format_version != GIT_REPO_VERSION) {
+		warning("not copying templates of "
+			"a wrong format version %d from '%s'",
+			repository_format_version,
+			template_dir);
+		closedir(dir);
+		return;
+	}
+
+	memcpy(path, git_dir, len);
+	if (len && path[len - 1] != '/')
+		path[len++] = '/';
+	path[len] = 0;
+	copy_templates_1(path, len,
+			 template_path, template_len,
+			 dir);
+	closedir(dir);
+}
+
+static int create_default_files(const char *template_path)
+{
+	const char *git_dir = get_git_dir();
+	unsigned len = strlen(git_dir);
+	static char path[PATH_MAX];
+	struct stat st1;
+	char repo_version_string[10];
+	char junk[2];
+	int reinit;
+	int filemode;
+
+	if (len > sizeof(path)-50)
+		die("insane git directory %s", git_dir);
+	memcpy(path, git_dir, len);
+
+	if (len && path[len-1] != '/')
+		path[len++] = '/';
+
+	/*
+	 * Create .git/refs/{heads,tags}
+	 */
+	safe_create_dir(git_path("refs"), 1);
+	safe_create_dir(git_path("refs/heads"), 1);
+	safe_create_dir(git_path("refs/tags"), 1);
+
+	/* First copy the templates -- we might have the default
+	 * config file there, in which case we would want to read
+	 * from it after installing.
+	 */
+	copy_templates(template_path);
+
+	git_config(git_default_config, NULL);
+	is_bare_repository_cfg = init_is_bare_repository;
+
+	/* reading existing config may have overwrote it */
+	if (init_shared_repository != -1)
+		shared_repository = init_shared_repository;
+
+	/*
+	 * We would have created the above under user's umask -- under
+	 * shared-repository settings, we would need to fix them up.
+	 */
+	if (shared_repository) {
+		adjust_shared_perm(get_git_dir());
+		adjust_shared_perm(git_path("refs"));
+		adjust_shared_perm(git_path("refs/heads"));
+		adjust_shared_perm(git_path("refs/tags"));
+	}
+
+	/*
+	 * Create the default symlink from ".git/HEAD" to the "master"
+	 * branch, if it does not exist yet.
+	 */
+	strcpy(path + len, "HEAD");
+	reinit = (!access(path, R_OK)
+		  || readlink(path, junk, sizeof(junk)-1) != -1);
+	if (!reinit) {
+		if (create_symref("HEAD", "refs/heads/master", NULL) < 0)
+			exit(1);
+	}
+
+	/* This forces creation of new config file */
+	sprintf(repo_version_string, "%d", GIT_REPO_VERSION);
+	git_config_set("core.repositoryformatversion", repo_version_string);
+
+	path[len] = 0;
+	strcpy(path + len, "config");
+
+	/* Check filemode trustability */
+	filemode = TEST_FILEMODE;
+	if (TEST_FILEMODE && !lstat(path, &st1)) {
+		struct stat st2;
+		filemode = (!chmod(path, st1.st_mode ^ S_IXUSR) &&
+				!lstat(path, &st2) &&
+				st1.st_mode != st2.st_mode);
+	}
+	git_config_set("core.filemode", filemode ? "true" : "false");
+
+	if (is_bare_repository())
+		git_config_set("core.bare", "true");
+	else {
+		const char *work_tree = get_git_work_tree();
+		git_config_set("core.bare", "false");
+		/* allow template config file to override the default */
+		if (log_all_ref_updates == -1)
+		    git_config_set("core.logallrefupdates", "true");
+		if (prefixcmp(git_dir, work_tree) ||
+		    strcmp(git_dir + strlen(work_tree), "/.git")) {
+			git_config_set("core.worktree", work_tree);
+		}
+	}
+
+	if (!reinit) {
+		/* Check if symlink is supported in the work tree */
+		path[len] = 0;
+		strcpy(path + len, "tXXXXXX");
+		if (!close(xmkstemp(path)) &&
+		    !unlink(path) &&
+		    !symlink("testing", path) &&
+		    !lstat(path, &st1) &&
+		    S_ISLNK(st1.st_mode))
+			unlink(path); /* good */
+		else
+			git_config_set("core.symlinks", "false");
+
+		/* Check if the filesystem is case-insensitive */
+		path[len] = 0;
+		strcpy(path + len, "CoNfIg");
+		if (!access(path, F_OK))
+			git_config_set("core.ignorecase", "true");
+	}
+
+	return reinit;
+}
+
+int init_db(const char *template_dir, unsigned int flags)
+{
+	const char *sha1_dir;
+	char *path;
+	int len, reinit;
+
+	safe_create_dir(get_git_dir(), 0);
+
+	init_is_bare_repository = is_bare_repository();
+
+	/* Check to see if the repository version is right.
+	 * Note that a newly created repository does not have
+	 * config file, so this will not fail.  What we are catching
+	 * is an attempt to reinitialize new repository with an old tool.
+	 */
+	check_repository_format();
+
+	reinit = create_default_files(template_dir);
+
+	sha1_dir = get_object_directory();
+	len = strlen(sha1_dir);
+	path = xmalloc(len + 40);
+	memcpy(path, sha1_dir, len);
+
+	safe_create_dir(sha1_dir, 1);
+	strcpy(path+len, "/pack");
+	safe_create_dir(path, 1);
+	strcpy(path+len, "/info");
+	safe_create_dir(path, 1);
+
+	if (shared_repository) {
+		char buf[10];
+		/* We do not spell "group" and such, so that
+		 * the configuration can be read by older version
+		 * of git. Note, we use octal numbers for new share modes,
+		 * and compatibility values for PERM_GROUP and
+		 * PERM_EVERYBODY.
+		 */
+		if (shared_repository < 0)
+			/* force to the mode value */
+			sprintf(buf, "0%o", -shared_repository);
+		else if (shared_repository == PERM_GROUP)
+			sprintf(buf, "%d", OLD_PERM_GROUP);
+		else if (shared_repository == PERM_EVERYBODY)
+			sprintf(buf, "%d", OLD_PERM_EVERYBODY);
+		else
+			die("oops");
+		git_config_set("core.sharedrepository", buf);
+		git_config_set("receive.denyNonFastforwards", "true");
+	}
+
+	if (!(flags & INIT_DB_QUIET)) {
+		const char *git_dir = get_git_dir();
+		int len = strlen(git_dir);
+		printf("%s%s Git repository in %s%s\n",
+		       reinit ? "Reinitialized existing" : "Initialized empty",
+		       shared_repository ? " shared" : "",
+		       git_dir, len && git_dir[len-1] != '/' ? "/" : "");
+	}
+
+	return 0;
+}
+
+static int guess_repository_type(const char *git_dir)
+{
+	char cwd[PATH_MAX];
+	const char *slash;
+
+	/*
+	 * "GIT_DIR=. git init" is always bare.
+	 * "GIT_DIR=`pwd` git init" too.
+	 */
+	if (!strcmp(".", git_dir))
+		return 1;
+	if (!getcwd(cwd, sizeof(cwd)))
+		die_errno("cannot tell cwd");
+	if (!strcmp(git_dir, cwd))
+		return 1;
+	/*
+	 * "GIT_DIR=.git or GIT_DIR=something/.git is usually not.
+	 */
+	if (!strcmp(git_dir, ".git"))
+		return 0;
+	slash = strrchr(git_dir, '/');
+	if (slash && !strcmp(slash, "/.git"))
+		return 0;
+
+	/*
+	 * Otherwise it is often bare.  At this point
+	 * we are just guessing.
+	 */
+	return 1;
+}
+
+static int shared_callback(const struct option *opt, const char *arg, int unset)
+{
+	*((int *) opt->value) = (arg) ? git_config_perm("arg", arg) : PERM_GROUP;
+	return 0;
+}
+
+static const char *const init_db_usage[] = {
+	"git init [-q | --quiet] [--bare] [--template=<template-directory>] [--shared[=<permissions>]] [directory]",
+	NULL
+};
+
+/*
+ * If you want to, you can share the DB area with any number of branches.
+ * That has advantages: you can save space by sharing all the SHA1 objects.
+ * On the other hand, it might just make lookup slower and messier. You
+ * be the judge.  The default case is to have one DB per managed directory.
+ */
+int cmd_init_db(int argc, const char **argv, const char *prefix)
+{
+	const char *git_dir;
+	const char *template_dir = NULL;
+	unsigned int flags = 0;
+	const struct option init_db_options[] = {
+		OPT_STRING(0, "template", &template_dir, "template-directory",
+				"provide the directory from which templates will be used"),
+		OPT_SET_INT(0, "bare", &is_bare_repository_cfg,
+				"create a bare repository", 1),
+		{ OPTION_CALLBACK, 0, "shared", &init_shared_repository,
+			"permissions",
+			"specify that the git repository is to be shared amongst several users",
+			PARSE_OPT_OPTARG | PARSE_OPT_NONEG, shared_callback, 0},
+		OPT_BIT('q', "quiet", &flags, "be quiet", INIT_DB_QUIET),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, init_db_options, init_db_usage, 0);
+
+	if (argc == 1) {
+		int mkdir_tried = 0;
+	retry:
+		if (chdir(argv[0]) < 0) {
+			if (!mkdir_tried) {
+				int saved;
+				/*
+				 * At this point we haven't read any configuration,
+				 * and we know shared_repository should always be 0;
+				 * but just in case we play safe.
+				 */
+				saved = shared_repository;
+				shared_repository = 0;
+				switch (safe_create_leading_directories_const(argv[0])) {
+				case -3:
+					errno = EEXIST;
+					/* fallthru */
+				case -1:
+					die_errno("cannot mkdir %s", argv[0]);
+					break;
+				default:
+					break;
+				}
+				shared_repository = saved;
+				if (mkdir(argv[0], 0777) < 0)
+					die_errno("cannot mkdir %s", argv[0]);
+				mkdir_tried = 1;
+				goto retry;
+			}
+			die_errno("cannot chdir to %s", argv[0]);
+		}
+	} else if (0 < argc) {
+		usage(init_db_usage[0]);
+	}
+	if (is_bare_repository_cfg == 1) {
+		static char git_dir[PATH_MAX+1];
+
+		setenv(GIT_DIR_ENVIRONMENT,
+			getcwd(git_dir, sizeof(git_dir)), 0);
+	}
+
+	if (init_shared_repository != -1)
+		shared_repository = init_shared_repository;
+
+	/*
+	 * GIT_WORK_TREE makes sense only in conjunction with GIT_DIR
+	 * without --bare.  Catch the error early.
+	 */
+	git_dir = getenv(GIT_DIR_ENVIRONMENT);
+	if ((!git_dir || is_bare_repository_cfg == 1)
+	    && getenv(GIT_WORK_TREE_ENVIRONMENT))
+		die("%s (or --work-tree=<directory>) not allowed without "
+		    "specifying %s (or --git-dir=<directory>)",
+		    GIT_WORK_TREE_ENVIRONMENT,
+		    GIT_DIR_ENVIRONMENT);
+
+	/*
+	 * Set up the default .git directory contents
+	 */
+	if (!git_dir)
+		git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
+
+	if (is_bare_repository_cfg < 0)
+		is_bare_repository_cfg = guess_repository_type(git_dir);
+
+	if (!is_bare_repository_cfg) {
+		if (git_dir) {
+			const char *git_dir_parent = strrchr(git_dir, '/');
+			if (git_dir_parent) {
+				char *rel = xstrndup(git_dir, git_dir_parent - git_dir);
+				git_work_tree_cfg = xstrdup(make_absolute_path(rel));
+				free(rel);
+			}
+		}
+		if (!git_work_tree_cfg) {
+			git_work_tree_cfg = xcalloc(PATH_MAX, 1);
+			if (!getcwd(git_work_tree_cfg, PATH_MAX))
+				die_errno ("Cannot access current working directory");
+		}
+		if (access(get_git_work_tree(), X_OK))
+			die_errno ("Cannot access work tree '%s'",
+				   get_git_work_tree());
+	}
+
+	set_git_dir(make_absolute_path(git_dir));
+
+	return init_db(template_dir, flags);
+}
diff --git a/builtin/log.c b/builtin/log.c
new file mode 100644
index 0000000..e0d5caa
--- /dev/null
+++ b/builtin/log.c
@@ -0,0 +1,1352 @@
+/*
+ * Builtin "git log" and related commands (show, whatchanged)
+ *
+ * (C) Copyright 2006 Linus Torvalds
+ *		 2006 Junio Hamano
+ */
+#include "cache.h"
+#include "color.h"
+#include "commit.h"
+#include "diff.h"
+#include "revision.h"
+#include "log-tree.h"
+#include "builtin.h"
+#include "tag.h"
+#include "reflog-walk.h"
+#include "patch-ids.h"
+#include "run-command.h"
+#include "shortlog.h"
+#include "remote.h"
+#include "string-list.h"
+#include "parse-options.h"
+
+/* Set a default date-time format for git log ("log.date" config variable) */
+static const char *default_date_mode = NULL;
+
+static int default_show_root = 1;
+static const char *fmt_patch_subject_prefix = "PATCH";
+static const char *fmt_pretty;
+
+static const char * const builtin_log_usage =
+	"git log [<options>] [<since>..<until>] [[--] <path>...]\n"
+	"   or: git show [options] <object>...";
+
+static void cmd_log_init(int argc, const char **argv, const char *prefix,
+		      struct rev_info *rev)
+{
+	int i;
+	int decoration_style = 0;
+
+	rev->abbrev = DEFAULT_ABBREV;
+	rev->commit_format = CMIT_FMT_DEFAULT;
+	if (fmt_pretty)
+		get_commit_format(fmt_pretty, rev);
+	rev->verbose_header = 1;
+	DIFF_OPT_SET(&rev->diffopt, RECURSIVE);
+	rev->show_root_diff = default_show_root;
+	rev->subject_prefix = fmt_patch_subject_prefix;
+	DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
+
+	if (default_date_mode)
+		rev->date_mode = parse_date_format(default_date_mode);
+
+	/*
+	 * Check for -h before setup_revisions(), or "git log -h" will
+	 * fail when run without a git directory.
+	 */
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage(builtin_log_usage);
+	argc = setup_revisions(argc, argv, rev, "HEAD");
+
+	if (!rev->show_notes_given && !rev->pretty_given)
+		rev->show_notes = 1;
+
+	if (rev->diffopt.pickaxe || rev->diffopt.filter)
+		rev->always_show_header = 0;
+	if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) {
+		rev->always_show_header = 0;
+		if (rev->diffopt.nr_paths != 1)
+			usage("git logs can only follow renames on one pathname at a time");
+	}
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!strcmp(arg, "--decorate")) {
+			decoration_style = DECORATE_SHORT_REFS;
+		} else if (!prefixcmp(arg, "--decorate=")) {
+			const char *v = skip_prefix(arg, "--decorate=");
+			if (!strcmp(v, "full"))
+				decoration_style = DECORATE_FULL_REFS;
+			else if (!strcmp(v, "short"))
+				decoration_style = DECORATE_SHORT_REFS;
+			else
+				die("invalid --decorate option: %s", arg);
+		} else if (!strcmp(arg, "--source")) {
+			rev->show_source = 1;
+		} else if (!strcmp(arg, "-h")) {
+			usage(builtin_log_usage);
+		} else
+			die("unrecognized argument: %s", arg);
+	}
+	if (decoration_style) {
+		rev->show_decorations = 1;
+		load_ref_decorations(decoration_style);
+	}
+}
+
+/*
+ * This gives a rough estimate for how many commits we
+ * will print out in the list.
+ */
+static int estimate_commit_count(struct rev_info *rev, struct commit_list *list)
+{
+	int n = 0;
+
+	while (list) {
+		struct commit *commit = list->item;
+		unsigned int flags = commit->object.flags;
+		list = list->next;
+		if (!(flags & (TREESAME | UNINTERESTING)))
+			n++;
+	}
+	return n;
+}
+
+static void show_early_header(struct rev_info *rev, const char *stage, int nr)
+{
+	if (rev->shown_one) {
+		rev->shown_one = 0;
+		if (rev->commit_format != CMIT_FMT_ONELINE)
+			putchar(rev->diffopt.line_termination);
+	}
+	printf("Final output: %d %s\n", nr, stage);
+}
+
+static struct itimerval early_output_timer;
+
+static void log_show_early(struct rev_info *revs, struct commit_list *list)
+{
+	int i = revs->early_output;
+	int show_header = 1;
+
+	sort_in_topological_order(&list, revs->lifo);
+	while (list && i) {
+		struct commit *commit = list->item;
+		switch (simplify_commit(revs, commit)) {
+		case commit_show:
+			if (show_header) {
+				int n = estimate_commit_count(revs, list);
+				show_early_header(revs, "incomplete", n);
+				show_header = 0;
+			}
+			log_tree_commit(revs, commit);
+			i--;
+			break;
+		case commit_ignore:
+			break;
+		case commit_error:
+			return;
+		}
+		list = list->next;
+	}
+
+	/* Did we already get enough commits for the early output? */
+	if (!i)
+		return;
+
+	/*
+	 * ..if no, then repeat it twice a second until we
+	 * do.
+	 *
+	 * NOTE! We don't use "it_interval", because if the
+	 * reader isn't listening, we want our output to be
+	 * throttled by the writing, and not have the timer
+	 * trigger every second even if we're blocked on a
+	 * reader!
+	 */
+	early_output_timer.it_value.tv_sec = 0;
+	early_output_timer.it_value.tv_usec = 500000;
+	setitimer(ITIMER_REAL, &early_output_timer, NULL);
+}
+
+static void early_output(int signal)
+{
+	show_early_output = log_show_early;
+}
+
+static void setup_early_output(struct rev_info *rev)
+{
+	struct sigaction sa;
+
+	/*
+	 * Set up the signal handler, minimally intrusively:
+	 * we only set a single volatile integer word (not
+	 * using sigatomic_t - trying to avoid unnecessary
+	 * system dependencies and headers), and using
+	 * SA_RESTART.
+	 */
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = early_output;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_RESTART;
+	sigaction(SIGALRM, &sa, NULL);
+
+	/*
+	 * If we can get the whole output in less than a
+	 * tenth of a second, don't even bother doing the
+	 * early-output thing..
+	 *
+	 * This is a one-time-only trigger.
+	 */
+	early_output_timer.it_value.tv_sec = 0;
+	early_output_timer.it_value.tv_usec = 100000;
+	setitimer(ITIMER_REAL, &early_output_timer, NULL);
+}
+
+static void finish_early_output(struct rev_info *rev)
+{
+	int n = estimate_commit_count(rev, rev->commits);
+	signal(SIGALRM, SIG_IGN);
+	show_early_header(rev, "done", n);
+}
+
+static int cmd_log_walk(struct rev_info *rev)
+{
+	struct commit *commit;
+
+	if (rev->early_output)
+		setup_early_output(rev);
+
+	if (prepare_revision_walk(rev))
+		die("revision walk setup failed");
+
+	if (rev->early_output)
+		finish_early_output(rev);
+
+	/*
+	 * For --check and --exit-code, the exit code is based on CHECK_FAILED
+	 * and HAS_CHANGES being accumulated in rev->diffopt, so be careful to
+	 * retain that state information if replacing rev->diffopt in this loop
+	 */
+	while ((commit = get_revision(rev)) != NULL) {
+		log_tree_commit(rev, commit);
+		if (!rev->reflog_info) {
+			/* we allow cycles in reflog ancestry */
+			free(commit->buffer);
+			commit->buffer = NULL;
+		}
+		free_commit_list(commit->parents);
+		commit->parents = NULL;
+	}
+	if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF &&
+	    DIFF_OPT_TST(&rev->diffopt, CHECK_FAILED)) {
+		return 02;
+	}
+	return diff_result_code(&rev->diffopt, 0);
+}
+
+static int git_log_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "format.pretty"))
+		return git_config_string(&fmt_pretty, var, value);
+	if (!strcmp(var, "format.subjectprefix"))
+		return git_config_string(&fmt_patch_subject_prefix, var, value);
+	if (!strcmp(var, "log.date"))
+		return git_config_string(&default_date_mode, var, value);
+	if (!strcmp(var, "log.showroot")) {
+		default_show_root = git_config_bool(var, value);
+		return 0;
+	}
+	return git_diff_ui_config(var, value, cb);
+}
+
+int cmd_whatchanged(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info rev;
+
+	git_config(git_log_config, NULL);
+
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	init_revisions(&rev, prefix);
+	rev.diff = 1;
+	rev.simplify_history = 0;
+	cmd_log_init(argc, argv, prefix, &rev);
+	if (!rev.diffopt.output_format)
+		rev.diffopt.output_format = DIFF_FORMAT_RAW;
+	return cmd_log_walk(&rev);
+}
+
+static void show_tagger(char *buf, int len, struct rev_info *rev)
+{
+	struct strbuf out = STRBUF_INIT;
+
+	pp_user_info("Tagger", rev->commit_format, &out, buf, rev->date_mode,
+		git_log_output_encoding ?
+		git_log_output_encoding: git_commit_encoding);
+	printf("%s", out.buf);
+	strbuf_release(&out);
+}
+
+static int show_object(const unsigned char *sha1, int show_tag_object,
+	struct rev_info *rev)
+{
+	unsigned long size;
+	enum object_type type;
+	char *buf = read_sha1_file(sha1, &type, &size);
+	int offset = 0;
+
+	if (!buf)
+		return error("Could not read object %s", sha1_to_hex(sha1));
+
+	if (show_tag_object)
+		while (offset < size && buf[offset] != '\n') {
+			int new_offset = offset + 1;
+			while (new_offset < size && buf[new_offset++] != '\n')
+				; /* do nothing */
+			if (!prefixcmp(buf + offset, "tagger "))
+				show_tagger(buf + offset + 7,
+					    new_offset - offset - 7, rev);
+			offset = new_offset;
+		}
+
+	if (offset < size)
+		fwrite(buf + offset, size - offset, 1, stdout);
+	free(buf);
+	return 0;
+}
+
+static int show_tree_object(const unsigned char *sha1,
+		const char *base, int baselen,
+		const char *pathname, unsigned mode, int stage, void *context)
+{
+	printf("%s%s\n", pathname, S_ISDIR(mode) ? "/" : "");
+	return 0;
+}
+
+int cmd_show(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info rev;
+	struct object_array_entry *objects;
+	int i, count, ret = 0;
+
+	git_config(git_log_config, NULL);
+
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	init_revisions(&rev, prefix);
+	rev.diff = 1;
+	rev.combine_merges = 1;
+	rev.dense_combined_merges = 1;
+	rev.always_show_header = 1;
+	rev.ignore_merges = 0;
+	rev.no_walk = 1;
+	cmd_log_init(argc, argv, prefix, &rev);
+
+	count = rev.pending.nr;
+	objects = rev.pending.objects;
+	for (i = 0; i < count && !ret; i++) {
+		struct object *o = objects[i].item;
+		const char *name = objects[i].name;
+		switch (o->type) {
+		case OBJ_BLOB:
+			ret = show_object(o->sha1, 0, NULL);
+			break;
+		case OBJ_TAG: {
+			struct tag *t = (struct tag *)o;
+
+			if (rev.shown_one)
+				putchar('\n');
+			printf("%stag %s%s\n",
+					diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
+					t->tag,
+					diff_get_color_opt(&rev.diffopt, DIFF_RESET));
+			ret = show_object(o->sha1, 1, &rev);
+			rev.shown_one = 1;
+			if (ret)
+				break;
+			o = parse_object(t->tagged->sha1);
+			if (!o)
+				ret = error("Could not read object %s",
+					    sha1_to_hex(t->tagged->sha1));
+			objects[i].item = o;
+			i--;
+			break;
+		}
+		case OBJ_TREE:
+			if (rev.shown_one)
+				putchar('\n');
+			printf("%stree %s%s\n\n",
+					diff_get_color_opt(&rev.diffopt, DIFF_COMMIT),
+					name,
+					diff_get_color_opt(&rev.diffopt, DIFF_RESET));
+			read_tree_recursive((struct tree *)o, "", 0, 0, NULL,
+					show_tree_object, NULL);
+			rev.shown_one = 1;
+			break;
+		case OBJ_COMMIT:
+			rev.pending.nr = rev.pending.alloc = 0;
+			rev.pending.objects = NULL;
+			add_object_array(o, name, &rev.pending);
+			ret = cmd_log_walk(&rev);
+			break;
+		default:
+			ret = error("Unknown type: %d", o->type);
+		}
+	}
+	free(objects);
+	return ret;
+}
+
+/*
+ * This is equivalent to "git log -g --abbrev-commit --pretty=oneline"
+ */
+int cmd_log_reflog(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info rev;
+
+	git_config(git_log_config, NULL);
+
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	init_revisions(&rev, prefix);
+	init_reflog_walk(&rev.reflog_info);
+	rev.abbrev_commit = 1;
+	rev.verbose_header = 1;
+	cmd_log_init(argc, argv, prefix, &rev);
+
+	/*
+	 * This means that we override whatever commit format the user gave
+	 * on the cmd line.  Sad, but cmd_log_init() currently doesn't
+	 * allow us to set a different default.
+	 */
+	rev.commit_format = CMIT_FMT_ONELINE;
+	rev.use_terminator = 1;
+	rev.always_show_header = 1;
+
+	/*
+	 * We get called through "git reflog", so unlike the other log
+	 * routines, we need to set up our pager manually..
+	 */
+	setup_pager();
+
+	return cmd_log_walk(&rev);
+}
+
+int cmd_log(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info rev;
+
+	git_config(git_log_config, NULL);
+
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	init_revisions(&rev, prefix);
+	rev.always_show_header = 1;
+	cmd_log_init(argc, argv, prefix, &rev);
+	return cmd_log_walk(&rev);
+}
+
+/* format-patch */
+
+static const char *fmt_patch_suffix = ".patch";
+static int numbered = 0;
+static int auto_number = 1;
+
+static char *default_attach = NULL;
+
+static char **extra_hdr;
+static int extra_hdr_nr;
+static int extra_hdr_alloc;
+
+static char **extra_to;
+static int extra_to_nr;
+static int extra_to_alloc;
+
+static char **extra_cc;
+static int extra_cc_nr;
+static int extra_cc_alloc;
+
+static void add_header(const char *value)
+{
+	int len = strlen(value);
+	while (len && value[len - 1] == '\n')
+		len--;
+	if (!strncasecmp(value, "to: ", 4)) {
+		ALLOC_GROW(extra_to, extra_to_nr + 1, extra_to_alloc);
+		extra_to[extra_to_nr++] = xstrndup(value + 4, len - 4);
+		return;
+	}
+	if (!strncasecmp(value, "cc: ", 4)) {
+		ALLOC_GROW(extra_cc, extra_cc_nr + 1, extra_cc_alloc);
+		extra_cc[extra_cc_nr++] = xstrndup(value + 4, len - 4);
+		return;
+	}
+	ALLOC_GROW(extra_hdr, extra_hdr_nr + 1, extra_hdr_alloc);
+	extra_hdr[extra_hdr_nr++] = xstrndup(value, len);
+}
+
+#define THREAD_SHALLOW 1
+#define THREAD_DEEP 2
+static int thread = 0;
+static int do_signoff = 0;
+
+static int git_format_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "format.headers")) {
+		if (!value)
+			die("format.headers without value");
+		add_header(value);
+		return 0;
+	}
+	if (!strcmp(var, "format.suffix"))
+		return git_config_string(&fmt_patch_suffix, var, value);
+	if (!strcmp(var, "format.cc")) {
+		if (!value)
+			return config_error_nonbool(var);
+		ALLOC_GROW(extra_cc, extra_cc_nr + 1, extra_cc_alloc);
+		extra_cc[extra_cc_nr++] = xstrdup(value);
+		return 0;
+	}
+	if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
+		return 0;
+	}
+	if (!strcmp(var, "format.numbered")) {
+		if (value && !strcasecmp(value, "auto")) {
+			auto_number = 1;
+			return 0;
+		}
+		numbered = git_config_bool(var, value);
+		auto_number = auto_number && numbered;
+		return 0;
+	}
+	if (!strcmp(var, "format.attach")) {
+		if (value && *value)
+			default_attach = xstrdup(value);
+		else
+			default_attach = xstrdup(git_version_string);
+		return 0;
+	}
+	if (!strcmp(var, "format.thread")) {
+		if (value && !strcasecmp(value, "deep")) {
+			thread = THREAD_DEEP;
+			return 0;
+		}
+		if (value && !strcasecmp(value, "shallow")) {
+			thread = THREAD_SHALLOW;
+			return 0;
+		}
+		thread = git_config_bool(var, value) && THREAD_SHALLOW;
+		return 0;
+	}
+	if (!strcmp(var, "format.signoff")) {
+		do_signoff = git_config_bool(var, value);
+		return 0;
+	}
+
+	return git_log_config(var, value, cb);
+}
+
+static FILE *realstdout = NULL;
+static const char *output_directory = NULL;
+static int outdir_offset;
+
+static int reopen_stdout(struct commit *commit, struct rev_info *rev)
+{
+	struct strbuf filename = STRBUF_INIT;
+	int suffix_len = strlen(fmt_patch_suffix) + 1;
+
+	if (output_directory) {
+		strbuf_addstr(&filename, output_directory);
+		if (filename.len >=
+		    PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
+			return error("name of output directory is too long");
+		if (filename.buf[filename.len - 1] != '/')
+			strbuf_addch(&filename, '/');
+	}
+
+	get_patch_filename(commit, rev->nr, fmt_patch_suffix, &filename);
+
+	if (!DIFF_OPT_TST(&rev->diffopt, QUICK))
+		fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
+
+	if (freopen(filename.buf, "w", stdout) == NULL)
+		return error("Cannot open patch file %s", filename.buf);
+
+	strbuf_release(&filename);
+	return 0;
+}
+
+static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix)
+{
+	struct rev_info check_rev;
+	struct commit *commit;
+	struct object *o1, *o2;
+	unsigned flags1, flags2;
+
+	if (rev->pending.nr != 2)
+		die("Need exactly one range.");
+
+	o1 = rev->pending.objects[0].item;
+	flags1 = o1->flags;
+	o2 = rev->pending.objects[1].item;
+	flags2 = o2->flags;
+
+	if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING))
+		die("Not a range.");
+
+	init_patch_ids(ids);
+
+	/* given a range a..b get all patch ids for b..a */
+	init_revisions(&check_rev, prefix);
+	o1->flags ^= UNINTERESTING;
+	o2->flags ^= UNINTERESTING;
+	add_pending_object(&check_rev, o1, "o1");
+	add_pending_object(&check_rev, o2, "o2");
+	if (prepare_revision_walk(&check_rev))
+		die("revision walk setup failed");
+
+	while ((commit = get_revision(&check_rev)) != NULL) {
+		/* ignore merges */
+		if (commit->parents && commit->parents->next)
+			continue;
+
+		add_commit_patch_id(commit, ids);
+	}
+
+	/* reset for next revision walk */
+	clear_commit_marks((struct commit *)o1,
+			SEEN | UNINTERESTING | SHOWN | ADDED);
+	clear_commit_marks((struct commit *)o2,
+			SEEN | UNINTERESTING | SHOWN | ADDED);
+	o1->flags = flags1;
+	o2->flags = flags2;
+}
+
+static void gen_message_id(struct rev_info *info, char *base)
+{
+	const char *committer = git_committer_info(IDENT_WARN_ON_NO_NAME);
+	const char *email_start = strrchr(committer, '<');
+	const char *email_end = strrchr(committer, '>');
+	struct strbuf buf = STRBUF_INIT;
+	if (!email_start || !email_end || email_start > email_end - 1)
+		die("Could not extract email from committer identity.");
+	strbuf_addf(&buf, "%s.%lu.git.%.*s", base,
+		    (unsigned long) time(NULL),
+		    (int)(email_end - email_start - 1), email_start + 1);
+	info->message_id = strbuf_detach(&buf, NULL);
+}
+
+static void make_cover_letter(struct rev_info *rev, int use_stdout,
+			      int numbered, int numbered_files,
+			      struct commit *origin,
+			      int nr, struct commit **list, struct commit *head)
+{
+	const char *committer;
+	const char *subject_start = NULL;
+	const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
+	const char *msg;
+	const char *extra_headers = rev->extra_headers;
+	struct shortlog log;
+	struct strbuf sb = STRBUF_INIT;
+	int i;
+	const char *encoding = "UTF-8";
+	struct diff_options opts;
+	int need_8bit_cte = 0;
+	struct commit *commit = NULL;
+
+	if (rev->commit_format != CMIT_FMT_EMAIL)
+		die("Cover letter needs email format");
+
+	committer = git_committer_info(0);
+
+	if (!numbered_files) {
+		/*
+		 * We fake a commit for the cover letter so we get the filename
+		 * desired.
+		 */
+		commit = xcalloc(1, sizeof(*commit));
+		commit->buffer = xmalloc(400);
+		snprintf(commit->buffer, 400,
+			"tree 0000000000000000000000000000000000000000\n"
+			"parent %s\n"
+			"author %s\n"
+			"committer %s\n\n"
+			"cover letter\n",
+			sha1_to_hex(head->object.sha1), committer, committer);
+	}
+
+	if (!use_stdout && reopen_stdout(commit, rev))
+		return;
+
+	if (commit) {
+
+		free(commit->buffer);
+		free(commit);
+	}
+
+	log_write_email_headers(rev, head, &subject_start, &extra_headers,
+				&need_8bit_cte);
+
+	for (i = 0; !need_8bit_cte && i < nr; i++)
+		if (has_non_ascii(list[i]->buffer))
+			need_8bit_cte = 1;
+
+	msg = body;
+	pp_user_info(NULL, CMIT_FMT_EMAIL, &sb, committer, DATE_RFC2822,
+		     encoding);
+	pp_title_line(CMIT_FMT_EMAIL, &msg, &sb, subject_start, extra_headers,
+		      encoding, need_8bit_cte);
+	pp_remainder(CMIT_FMT_EMAIL, &msg, &sb, 0);
+	printf("%s\n", sb.buf);
+
+	strbuf_release(&sb);
+
+	shortlog_init(&log);
+	log.wrap_lines = 1;
+	log.wrap = 72;
+	log.in1 = 2;
+	log.in2 = 4;
+	for (i = 0; i < nr; i++)
+		shortlog_add_commit(&log, list[i]);
+
+	shortlog_output(&log);
+
+	/*
+	 * We can only do diffstat with a unique reference point
+	 */
+	if (!origin)
+		return;
+
+	memcpy(&opts, &rev->diffopt, sizeof(opts));
+	opts.output_format = DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
+
+	diff_setup_done(&opts);
+
+	diff_tree_sha1(origin->tree->object.sha1,
+		       head->tree->object.sha1,
+		       "", &opts);
+	diffcore_std(&opts);
+	diff_flush(&opts);
+
+	printf("\n");
+}
+
+static const char *clean_message_id(const char *msg_id)
+{
+	char ch;
+	const char *a, *z, *m;
+
+	m = msg_id;
+	while ((ch = *m) && (isspace(ch) || (ch == '<')))
+		m++;
+	a = m;
+	z = NULL;
+	while ((ch = *m)) {
+		if (!isspace(ch) && (ch != '>'))
+			z = m;
+		m++;
+	}
+	if (!z)
+		die("insane in-reply-to: %s", msg_id);
+	if (++z == m)
+		return a;
+	return xmemdupz(a, z - a);
+}
+
+static const char *set_outdir(const char *prefix, const char *output_directory)
+{
+	if (output_directory && is_absolute_path(output_directory))
+		return output_directory;
+
+	if (!prefix || !*prefix) {
+		if (output_directory)
+			return output_directory;
+		/* The user did not explicitly ask for "./" */
+		outdir_offset = 2;
+		return "./";
+	}
+
+	outdir_offset = strlen(prefix);
+	if (!output_directory)
+		return prefix;
+
+	return xstrdup(prefix_filename(prefix, outdir_offset,
+				       output_directory));
+}
+
+static const char * const builtin_format_patch_usage[] = {
+	"git format-patch [options] [<since> | <revision range>]",
+	NULL
+};
+
+static int keep_subject = 0;
+
+static int keep_callback(const struct option *opt, const char *arg, int unset)
+{
+	((struct rev_info *)opt->value)->total = -1;
+	keep_subject = 1;
+	return 0;
+}
+
+static int subject_prefix = 0;
+
+static int subject_prefix_callback(const struct option *opt, const char *arg,
+			    int unset)
+{
+	subject_prefix = 1;
+	((struct rev_info *)opt->value)->subject_prefix = arg;
+	return 0;
+}
+
+static int numbered_cmdline_opt = 0;
+
+static int numbered_callback(const struct option *opt, const char *arg,
+			     int unset)
+{
+	*(int *)opt->value = numbered_cmdline_opt = unset ? 0 : 1;
+	if (unset)
+		auto_number =  0;
+	return 0;
+}
+
+static int no_numbered_callback(const struct option *opt, const char *arg,
+				int unset)
+{
+	return numbered_callback(opt, arg, 1);
+}
+
+static int output_directory_callback(const struct option *opt, const char *arg,
+			      int unset)
+{
+	const char **dir = (const char **)opt->value;
+	if (*dir)
+		die("Two output directories?");
+	*dir = arg;
+	return 0;
+}
+
+static int thread_callback(const struct option *opt, const char *arg, int unset)
+{
+	int *thread = (int *)opt->value;
+	if (unset)
+		*thread = 0;
+	else if (!arg || !strcmp(arg, "shallow"))
+		*thread = THREAD_SHALLOW;
+	else if (!strcmp(arg, "deep"))
+		*thread = THREAD_DEEP;
+	else
+		return 1;
+	return 0;
+}
+
+static int attach_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct rev_info *rev = (struct rev_info *)opt->value;
+	if (unset)
+		rev->mime_boundary = NULL;
+	else if (arg)
+		rev->mime_boundary = arg;
+	else
+		rev->mime_boundary = git_version_string;
+	rev->no_inline = unset ? 0 : 1;
+	return 0;
+}
+
+static int inline_callback(const struct option *opt, const char *arg, int unset)
+{
+	struct rev_info *rev = (struct rev_info *)opt->value;
+	if (unset)
+		rev->mime_boundary = NULL;
+	else if (arg)
+		rev->mime_boundary = arg;
+	else
+		rev->mime_boundary = git_version_string;
+	rev->no_inline = 0;
+	return 0;
+}
+
+static int header_callback(const struct option *opt, const char *arg, int unset)
+{
+	add_header(arg);
+	return 0;
+}
+
+static int cc_callback(const struct option *opt, const char *arg, int unset)
+{
+	ALLOC_GROW(extra_cc, extra_cc_nr + 1, extra_cc_alloc);
+	extra_cc[extra_cc_nr++] = xstrdup(arg);
+	return 0;
+}
+
+int cmd_format_patch(int argc, const char **argv, const char *prefix)
+{
+	struct commit *commit;
+	struct commit **list = NULL;
+	struct rev_info rev;
+	int nr = 0, total, i;
+	int use_stdout = 0;
+	int start_number = -1;
+	int numbered_files = 0;		/* _just_ numbers */
+	int ignore_if_in_upstream = 0;
+	int cover_letter = 0;
+	int boundary_count = 0;
+	int no_binary_diff = 0;
+	struct commit *origin = NULL, *head = NULL;
+	const char *in_reply_to = NULL;
+	struct patch_ids ids;
+	char *add_signoff = NULL;
+	struct strbuf buf = STRBUF_INIT;
+	int use_patch_format = 0;
+	const struct option builtin_format_patch_options[] = {
+		{ OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
+			    "use [PATCH n/m] even with a single patch",
+			    PARSE_OPT_NOARG, numbered_callback },
+		{ OPTION_CALLBACK, 'N', "no-numbered", &numbered, NULL,
+			    "use [PATCH] even with multiple patches",
+			    PARSE_OPT_NOARG, no_numbered_callback },
+		OPT_BOOLEAN('s', "signoff", &do_signoff, "add Signed-off-by:"),
+		OPT_BOOLEAN(0, "stdout", &use_stdout,
+			    "print patches to standard out"),
+		OPT_BOOLEAN(0, "cover-letter", &cover_letter,
+			    "generate a cover letter"),
+		OPT_BOOLEAN(0, "numbered-files", &numbered_files,
+			    "use simple number sequence for output file names"),
+		OPT_STRING(0, "suffix", &fmt_patch_suffix, "sfx",
+			    "use <sfx> instead of '.patch'"),
+		OPT_INTEGER(0, "start-number", &start_number,
+			    "start numbering patches at <n> instead of 1"),
+		{ OPTION_CALLBACK, 0, "subject-prefix", &rev, "prefix",
+			    "Use [<prefix>] instead of [PATCH]",
+			    PARSE_OPT_NONEG, subject_prefix_callback },
+		{ OPTION_CALLBACK, 'o', "output-directory", &output_directory,
+			    "dir", "store resulting files in <dir>",
+			    PARSE_OPT_NONEG, output_directory_callback },
+		{ OPTION_CALLBACK, 'k', "keep-subject", &rev, NULL,
+			    "don't strip/add [PATCH]",
+			    PARSE_OPT_NOARG | PARSE_OPT_NONEG, keep_callback },
+		OPT_BOOLEAN(0, "no-binary", &no_binary_diff,
+			    "don't output binary diffs"),
+		OPT_BOOLEAN(0, "ignore-if-in-upstream", &ignore_if_in_upstream,
+			    "don't include a patch matching a commit upstream"),
+		{ OPTION_BOOLEAN, 'p', "no-stat", &use_patch_format, NULL,
+		  "show patch format instead of default (patch + stat)",
+		  PARSE_OPT_NONEG | PARSE_OPT_NOARG },
+		OPT_GROUP("Messaging"),
+		{ OPTION_CALLBACK, 0, "add-header", NULL, "header",
+			    "add email header", PARSE_OPT_NONEG,
+			    header_callback },
+		{ OPTION_CALLBACK, 0, "cc", NULL, "email", "add Cc: header",
+			    PARSE_OPT_NONEG, cc_callback },
+		OPT_STRING(0, "in-reply-to", &in_reply_to, "message-id",
+			    "make first mail a reply to <message-id>"),
+		{ OPTION_CALLBACK, 0, "attach", &rev, "boundary",
+			    "attach the patch", PARSE_OPT_OPTARG,
+			    attach_callback },
+		{ OPTION_CALLBACK, 0, "inline", &rev, "boundary",
+			    "inline the patch",
+			    PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
+			    inline_callback },
+		{ OPTION_CALLBACK, 0, "thread", &thread, "style",
+			    "enable message threading, styles: shallow, deep",
+			    PARSE_OPT_OPTARG, thread_callback },
+		OPT_END()
+	};
+
+	git_config(git_format_config, NULL);
+	init_revisions(&rev, prefix);
+	rev.commit_format = CMIT_FMT_EMAIL;
+	rev.verbose_header = 1;
+	rev.diff = 1;
+	rev.combine_merges = 0;
+	rev.ignore_merges = 1;
+	DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
+
+	rev.subject_prefix = fmt_patch_subject_prefix;
+
+	if (default_attach) {
+		rev.mime_boundary = default_attach;
+		rev.no_inline = 1;
+	}
+
+	/*
+	 * Parse the arguments before setup_revisions(), or something
+	 * like "git format-patch -o a123 HEAD^.." may fail; a123 is
+	 * possibly a valid SHA1.
+	 */
+	argc = parse_options(argc, argv, prefix, builtin_format_patch_options,
+			     builtin_format_patch_usage,
+			     PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN |
+			     PARSE_OPT_KEEP_DASHDASH);
+
+	if (do_signoff) {
+		const char *committer;
+		const char *endpos;
+		committer = git_committer_info(IDENT_ERROR_ON_NO_NAME);
+		endpos = strchr(committer, '>');
+		if (!endpos)
+			die("bogus committer info %s", committer);
+		add_signoff = xmemdupz(committer, endpos - committer + 1);
+	}
+
+	for (i = 0; i < extra_hdr_nr; i++) {
+		strbuf_addstr(&buf, extra_hdr[i]);
+		strbuf_addch(&buf, '\n');
+	}
+
+	if (extra_to_nr)
+		strbuf_addstr(&buf, "To: ");
+	for (i = 0; i < extra_to_nr; i++) {
+		if (i)
+			strbuf_addstr(&buf, "    ");
+		strbuf_addstr(&buf, extra_to[i]);
+		if (i + 1 < extra_to_nr)
+			strbuf_addch(&buf, ',');
+		strbuf_addch(&buf, '\n');
+	}
+
+	if (extra_cc_nr)
+		strbuf_addstr(&buf, "Cc: ");
+	for (i = 0; i < extra_cc_nr; i++) {
+		if (i)
+			strbuf_addstr(&buf, "    ");
+		strbuf_addstr(&buf, extra_cc[i]);
+		if (i + 1 < extra_cc_nr)
+			strbuf_addch(&buf, ',');
+		strbuf_addch(&buf, '\n');
+	}
+
+	rev.extra_headers = strbuf_detach(&buf, NULL);
+
+	if (start_number < 0)
+		start_number = 1;
+
+	/*
+	 * If numbered is set solely due to format.numbered in config,
+	 * and it would conflict with --keep-subject (-k) from the
+	 * command line, reset "numbered".
+	 */
+	if (numbered && keep_subject && !numbered_cmdline_opt)
+		numbered = 0;
+
+	if (numbered && keep_subject)
+		die ("-n and -k are mutually exclusive.");
+	if (keep_subject && subject_prefix)
+		die ("--subject-prefix and -k are mutually exclusive.");
+
+	argc = setup_revisions(argc, argv, &rev, "HEAD");
+	if (argc > 1)
+		die ("unrecognized argument: %s", argv[1]);
+
+	if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
+		die("--name-only does not make sense");
+	if (rev.diffopt.output_format & DIFF_FORMAT_NAME_STATUS)
+		die("--name-status does not make sense");
+	if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
+		die("--check does not make sense");
+
+	if (!use_patch_format &&
+		(!rev.diffopt.output_format ||
+		 rev.diffopt.output_format == DIFF_FORMAT_PATCH))
+		rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
+
+	/* Always generate a patch */
+	rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
+
+	if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
+		DIFF_OPT_SET(&rev.diffopt, BINARY);
+
+	if (!use_stdout)
+		output_directory = set_outdir(prefix, output_directory);
+
+	if (output_directory) {
+		if (use_stdout)
+			die("standard output, or directory, which one?");
+		if (mkdir(output_directory, 0777) < 0 && errno != EEXIST)
+			die_errno("Could not create directory '%s'",
+				  output_directory);
+	}
+
+	if (rev.pending.nr == 1) {
+		if (rev.max_count < 0 && !rev.show_root_diff) {
+			/*
+			 * This is traditional behaviour of "git format-patch
+			 * origin" that prepares what the origin side still
+			 * does not have.
+			 */
+			rev.pending.objects[0].item->flags |= UNINTERESTING;
+			add_head_to_pending(&rev);
+		}
+		/*
+		 * Otherwise, it is "format-patch -22 HEAD", and/or
+		 * "format-patch --root HEAD".  The user wants
+		 * get_revision() to do the usual traversal.
+		 */
+	}
+
+	/*
+	 * We cannot move this anywhere earlier because we do want to
+	 * know if --root was given explicitly from the command line.
+	 */
+	rev.show_root_diff = 1;
+
+	if (cover_letter) {
+		/* remember the range */
+		int i;
+		for (i = 0; i < rev.pending.nr; i++) {
+			struct object *o = rev.pending.objects[i].item;
+			if (!(o->flags & UNINTERESTING))
+				head = (struct commit *)o;
+		}
+		/* We can't generate a cover letter without any patches */
+		if (!head)
+			return 0;
+	}
+
+	if (ignore_if_in_upstream)
+		get_patch_ids(&rev, &ids, prefix);
+
+	if (!use_stdout)
+		realstdout = xfdopen(xdup(1), "w");
+
+	if (prepare_revision_walk(&rev))
+		die("revision walk setup failed");
+	rev.boundary = 1;
+	while ((commit = get_revision(&rev)) != NULL) {
+		if (commit->object.flags & BOUNDARY) {
+			boundary_count++;
+			origin = (boundary_count == 1) ? commit : NULL;
+			continue;
+		}
+
+		/* ignore merges */
+		if (commit->parents && commit->parents->next)
+			continue;
+
+		if (ignore_if_in_upstream &&
+				has_commit_patch_id(commit, &ids))
+			continue;
+
+		nr++;
+		list = xrealloc(list, nr * sizeof(list[0]));
+		list[nr - 1] = commit;
+	}
+	total = nr;
+	if (!keep_subject && auto_number && total > 1)
+		numbered = 1;
+	if (numbered)
+		rev.total = total + start_number - 1;
+	if (in_reply_to || thread || cover_letter)
+		rev.ref_message_ids = xcalloc(1, sizeof(struct string_list));
+	if (in_reply_to) {
+		const char *msgid = clean_message_id(in_reply_to);
+		string_list_append(msgid, rev.ref_message_ids);
+	}
+	rev.numbered_files = numbered_files;
+	rev.patch_suffix = fmt_patch_suffix;
+	if (cover_letter) {
+		if (thread)
+			gen_message_id(&rev, "cover");
+		make_cover_letter(&rev, use_stdout, numbered, numbered_files,
+				  origin, nr, list, head);
+		total++;
+		start_number--;
+	}
+	rev.add_signoff = add_signoff;
+	while (0 <= --nr) {
+		int shown;
+		commit = list[nr];
+		rev.nr = total - nr + (start_number - 1);
+		/* Make the second and subsequent mails replies to the first */
+		if (thread) {
+			/* Have we already had a message ID? */
+			if (rev.message_id) {
+				/*
+				 * For deep threading: make every mail
+				 * a reply to the previous one, no
+				 * matter what other options are set.
+				 *
+				 * For shallow threading:
+				 *
+				 * Without --cover-letter and
+				 * --in-reply-to, make every mail a
+				 * reply to the one before.
+				 *
+				 * With --in-reply-to but no
+				 * --cover-letter, make every mail a
+				 * reply to the <reply-to>.
+				 *
+				 * With --cover-letter, make every
+				 * mail but the cover letter a reply
+				 * to the cover letter.  The cover
+				 * letter is a reply to the
+				 * --in-reply-to, if specified.
+				 */
+				if (thread == THREAD_SHALLOW
+				    && rev.ref_message_ids->nr > 0
+				    && (!cover_letter || rev.nr > 1))
+					free(rev.message_id);
+				else
+					string_list_append(rev.message_id,
+							   rev.ref_message_ids);
+			}
+			gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
+		}
+
+		if (!use_stdout && reopen_stdout(numbered_files ? NULL : commit,
+						 &rev))
+			die("Failed to create output files");
+		shown = log_tree_commit(&rev, commit);
+		free(commit->buffer);
+		commit->buffer = NULL;
+
+		/* We put one extra blank line between formatted
+		 * patches and this flag is used by log-tree code
+		 * to see if it needs to emit a LF before showing
+		 * the log; when using one file per patch, we do
+		 * not want the extra blank line.
+		 */
+		if (!use_stdout)
+			rev.shown_one = 0;
+		if (shown) {
+			if (rev.mime_boundary)
+				printf("\n--%s%s--\n\n\n",
+				       mime_boundary_leader,
+				       rev.mime_boundary);
+			else
+				printf("-- \n%s\n\n", git_version_string);
+		}
+		if (!use_stdout)
+			fclose(stdout);
+	}
+	free(list);
+	if (ignore_if_in_upstream)
+		free_patch_ids(&ids);
+	return 0;
+}
+
+static int add_pending_commit(const char *arg, struct rev_info *revs, int flags)
+{
+	unsigned char sha1[20];
+	if (get_sha1(arg, sha1) == 0) {
+		struct commit *commit = lookup_commit_reference(sha1);
+		if (commit) {
+			commit->object.flags |= flags;
+			add_pending_object(revs, &commit->object, arg);
+			return 0;
+		}
+	}
+	return -1;
+}
+
+static const char cherry_usage[] =
+"git cherry [-v] [<upstream> [<head> [<limit>]]]";
+int cmd_cherry(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info revs;
+	struct patch_ids ids;
+	struct commit *commit;
+	struct commit_list *list = NULL;
+	struct branch *current_branch;
+	const char *upstream;
+	const char *head = "HEAD";
+	const char *limit = NULL;
+	int verbose = 0;
+
+	if (argc > 1 && !strcmp(argv[1], "-v")) {
+		verbose = 1;
+		argc--;
+		argv++;
+	}
+
+	if (argc > 1 && !strcmp(argv[1], "-h"))
+		usage(cherry_usage);
+
+	switch (argc) {
+	case 4:
+		limit = argv[3];
+		/* FALLTHROUGH */
+	case 3:
+		head = argv[2];
+		/* FALLTHROUGH */
+	case 2:
+		upstream = argv[1];
+		break;
+	default:
+		current_branch = branch_get(NULL);
+		if (!current_branch || !current_branch->merge
+					|| !current_branch->merge[0]
+					|| !current_branch->merge[0]->dst) {
+			fprintf(stderr, "Could not find a tracked"
+					" remote branch, please"
+					" specify <upstream> manually.\n");
+			usage(cherry_usage);
+		}
+
+		upstream = current_branch->merge[0]->dst;
+	}
+
+	init_revisions(&revs, prefix);
+	revs.diff = 1;
+	revs.combine_merges = 0;
+	revs.ignore_merges = 1;
+	DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
+
+	if (add_pending_commit(head, &revs, 0))
+		die("Unknown commit %s", head);
+	if (add_pending_commit(upstream, &revs, UNINTERESTING))
+		die("Unknown commit %s", upstream);
+
+	/* Don't say anything if head and upstream are the same. */
+	if (revs.pending.nr == 2) {
+		struct object_array_entry *o = revs.pending.objects;
+		if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
+			return 0;
+	}
+
+	get_patch_ids(&revs, &ids, prefix);
+
+	if (limit && add_pending_commit(limit, &revs, UNINTERESTING))
+		die("Unknown commit %s", limit);
+
+	/* reverse the list of commits */
+	if (prepare_revision_walk(&revs))
+		die("revision walk setup failed");
+	while ((commit = get_revision(&revs)) != NULL) {
+		/* ignore merges */
+		if (commit->parents && commit->parents->next)
+			continue;
+
+		commit_list_insert(commit, &list);
+	}
+
+	while (list) {
+		char sign = '+';
+
+		commit = list->item;
+		if (has_commit_patch_id(commit, &ids))
+			sign = '-';
+
+		if (verbose) {
+			struct strbuf buf = STRBUF_INIT;
+			struct pretty_print_context ctx = {0};
+			pretty_print_commit(CMIT_FMT_ONELINE, commit,
+					    &buf, &ctx);
+			printf("%c %s %s\n", sign,
+			       sha1_to_hex(commit->object.sha1), buf.buf);
+			strbuf_release(&buf);
+		}
+		else {
+			printf("%c %s\n", sign,
+			       sha1_to_hex(commit->object.sha1));
+		}
+
+		list = list->next;
+	}
+
+	free_patch_ids(&ids);
+	return 0;
+}
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
new file mode 100644
index 0000000..b065061
--- /dev/null
+++ b/builtin/ls-files.c
@@ -0,0 +1,606 @@
+/*
+ * This merges the file listing in the directory cache index
+ * with the actual working directory list, and shows different
+ * combinations of the two.
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "quote.h"
+#include "dir.h"
+#include "builtin.h"
+#include "tree.h"
+#include "parse-options.h"
+#include "resolve-undo.h"
+#include "string-list.h"
+
+static int abbrev;
+static int show_deleted;
+static int show_cached;
+static int show_others;
+static int show_stage;
+static int show_unmerged;
+static int show_resolve_undo;
+static int show_modified;
+static int show_killed;
+static int show_valid_bit;
+static int line_terminator = '\n';
+
+static int prefix_len;
+static int prefix_offset;
+static const char **pathspec;
+static int error_unmatch;
+static char *ps_matched;
+static const char *with_tree;
+static int exc_given;
+
+static const char *tag_cached = "";
+static const char *tag_unmerged = "";
+static const char *tag_removed = "";
+static const char *tag_other = "";
+static const char *tag_killed = "";
+static const char *tag_modified = "";
+static const char *tag_skip_worktree = "";
+static const char *tag_resolve_undo = "";
+
+static void show_dir_entry(const char *tag, struct dir_entry *ent)
+{
+	int len = prefix_len;
+	int offset = prefix_offset;
+
+	if (len >= ent->len)
+		die("git ls-files: internal error - directory entry not superset of prefix");
+
+	if (!match_pathspec(pathspec, ent->name, ent->len, len, ps_matched))
+		return;
+
+	fputs(tag, stdout);
+	write_name_quoted(ent->name + offset, stdout, line_terminator);
+}
+
+static void show_other_files(struct dir_struct *dir)
+{
+	int i;
+
+	for (i = 0; i < dir->nr; i++) {
+		struct dir_entry *ent = dir->entries[i];
+		if (!cache_name_is_other(ent->name, ent->len))
+			continue;
+		show_dir_entry(tag_other, ent);
+	}
+}
+
+static void show_killed_files(struct dir_struct *dir)
+{
+	int i;
+	for (i = 0; i < dir->nr; i++) {
+		struct dir_entry *ent = dir->entries[i];
+		char *cp, *sp;
+		int pos, len, killed = 0;
+
+		for (cp = ent->name; cp - ent->name < ent->len; cp = sp + 1) {
+			sp = strchr(cp, '/');
+			if (!sp) {
+				/* If ent->name is prefix of an entry in the
+				 * cache, it will be killed.
+				 */
+				pos = cache_name_pos(ent->name, ent->len);
+				if (0 <= pos)
+					die("bug in show-killed-files");
+				pos = -pos - 1;
+				while (pos < active_nr &&
+				       ce_stage(active_cache[pos]))
+					pos++; /* skip unmerged */
+				if (active_nr <= pos)
+					break;
+				/* pos points at a name immediately after
+				 * ent->name in the cache.  Does it expect
+				 * ent->name to be a directory?
+				 */
+				len = ce_namelen(active_cache[pos]);
+				if ((ent->len < len) &&
+				    !strncmp(active_cache[pos]->name,
+					     ent->name, ent->len) &&
+				    active_cache[pos]->name[ent->len] == '/')
+					killed = 1;
+				break;
+			}
+			if (0 <= cache_name_pos(ent->name, sp - ent->name)) {
+				/* If any of the leading directories in
+				 * ent->name is registered in the cache,
+				 * ent->name will be killed.
+				 */
+				killed = 1;
+				break;
+			}
+		}
+		if (killed)
+			show_dir_entry(tag_killed, dir->entries[i]);
+	}
+}
+
+static void show_ce_entry(const char *tag, struct cache_entry *ce)
+{
+	int len = prefix_len;
+	int offset = prefix_offset;
+
+	if (len >= ce_namelen(ce))
+		die("git ls-files: internal error - cache entry not superset of prefix");
+
+	if (!match_pathspec(pathspec, ce->name, ce_namelen(ce), len, ps_matched))
+		return;
+
+	if (tag && *tag && show_valid_bit &&
+	    (ce->ce_flags & CE_VALID)) {
+		static char alttag[4];
+		memcpy(alttag, tag, 3);
+		if (isalpha(tag[0]))
+			alttag[0] = tolower(tag[0]);
+		else if (tag[0] == '?')
+			alttag[0] = '!';
+		else {
+			alttag[0] = 'v';
+			alttag[1] = tag[0];
+			alttag[2] = ' ';
+			alttag[3] = 0;
+		}
+		tag = alttag;
+	}
+
+	if (!show_stage) {
+		fputs(tag, stdout);
+	} else {
+		printf("%s%06o %s %d\t",
+		       tag,
+		       ce->ce_mode,
+		       abbrev ? find_unique_abbrev(ce->sha1,abbrev)
+				: sha1_to_hex(ce->sha1),
+		       ce_stage(ce));
+	}
+	write_name_quoted(ce->name + offset, stdout, line_terminator);
+}
+
+static int show_one_ru(struct string_list_item *item, void *cbdata)
+{
+	int offset = prefix_offset;
+	const char *path = item->string;
+	struct resolve_undo_info *ui = item->util;
+	int i, len;
+
+	len = strlen(path);
+	if (len < prefix_len)
+		return 0; /* outside of the prefix */
+	if (!match_pathspec(pathspec, path, len, prefix_len, ps_matched))
+		return 0; /* uninterested */
+	for (i = 0; i < 3; i++) {
+		if (!ui->mode[i])
+			continue;
+		printf("%s%06o %s %d\t", tag_resolve_undo, ui->mode[i],
+		       abbrev
+		       ? find_unique_abbrev(ui->sha1[i], abbrev)
+		       : sha1_to_hex(ui->sha1[i]),
+		       i + 1);
+		write_name_quoted(path + offset, stdout, line_terminator);
+	}
+	return 0;
+}
+
+static void show_ru_info(const char *prefix)
+{
+	if (!the_index.resolve_undo)
+		return;
+	for_each_string_list(show_one_ru, the_index.resolve_undo, NULL);
+}
+
+static void show_files(struct dir_struct *dir, const char *prefix)
+{
+	int i;
+
+	/* For cached/deleted files we don't need to even do the readdir */
+	if (show_others || show_killed) {
+		fill_directory(dir, pathspec);
+		if (show_others)
+			show_other_files(dir);
+		if (show_killed)
+			show_killed_files(dir);
+	}
+	if (show_cached | show_stage) {
+		for (i = 0; i < active_nr; i++) {
+			struct cache_entry *ce = active_cache[i];
+			int dtype = ce_to_dtype(ce);
+			if (dir->flags & DIR_SHOW_IGNORED &&
+			    !excluded(dir, ce->name, &dtype))
+				continue;
+			if (show_unmerged && !ce_stage(ce))
+				continue;
+			if (ce->ce_flags & CE_UPDATE)
+				continue;
+			show_ce_entry(ce_stage(ce) ? tag_unmerged :
+				(ce_skip_worktree(ce) ? tag_skip_worktree : tag_cached), ce);
+		}
+	}
+	if (show_deleted | show_modified) {
+		for (i = 0; i < active_nr; i++) {
+			struct cache_entry *ce = active_cache[i];
+			struct stat st;
+			int err;
+			int dtype = ce_to_dtype(ce);
+			if (dir->flags & DIR_SHOW_IGNORED &&
+			    !excluded(dir, ce->name, &dtype))
+				continue;
+			if (ce->ce_flags & CE_UPDATE)
+				continue;
+			if (ce_skip_worktree(ce))
+				continue;
+			err = lstat(ce->name, &st);
+			if (show_deleted && err)
+				show_ce_entry(tag_removed, ce);
+			if (show_modified && ce_modified(ce, &st, 0))
+				show_ce_entry(tag_modified, ce);
+		}
+	}
+}
+
+/*
+ * Prune the index to only contain stuff starting with "prefix"
+ */
+static void prune_cache(const char *prefix)
+{
+	int pos = cache_name_pos(prefix, prefix_len);
+	unsigned int first, last;
+
+	if (pos < 0)
+		pos = -pos-1;
+	memmove(active_cache, active_cache + pos,
+		(active_nr - pos) * sizeof(struct cache_entry *));
+	active_nr -= pos;
+	first = 0;
+	last = active_nr;
+	while (last > first) {
+		int next = (last + first) >> 1;
+		struct cache_entry *ce = active_cache[next];
+		if (!strncmp(ce->name, prefix, prefix_len)) {
+			first = next+1;
+			continue;
+		}
+		last = next;
+	}
+	active_nr = last;
+}
+
+static const char *verify_pathspec(const char *prefix)
+{
+	const char **p, *n, *prev;
+	unsigned long max;
+
+	prev = NULL;
+	max = PATH_MAX;
+	for (p = pathspec; (n = *p) != NULL; p++) {
+		int i, len = 0;
+		for (i = 0; i < max; i++) {
+			char c = n[i];
+			if (prev && prev[i] != c)
+				break;
+			if (!c || c == '*' || c == '?')
+				break;
+			if (c == '/')
+				len = i+1;
+		}
+		prev = n;
+		if (len < max) {
+			max = len;
+			if (!max)
+				break;
+		}
+	}
+
+	if (prefix_offset > max || memcmp(prev, prefix, prefix_offset))
+		die("git ls-files: cannot generate relative filenames containing '..'");
+
+	prefix_len = max;
+	return max ? xmemdupz(prev, max) : NULL;
+}
+
+static void strip_trailing_slash_from_submodules(void)
+{
+	const char **p;
+
+	for (p = pathspec; *p != NULL; p++) {
+		int len = strlen(*p), pos;
+
+		if (len < 1 || (*p)[len - 1] != '/')
+			continue;
+		pos = cache_name_pos(*p, len - 1);
+		if (pos >= 0 && S_ISGITLINK(active_cache[pos]->ce_mode))
+			*p = xstrndup(*p, len - 1);
+	}
+}
+
+/*
+ * Read the tree specified with --with-tree option
+ * (typically, HEAD) into stage #1 and then
+ * squash them down to stage #0.  This is used for
+ * --error-unmatch to list and check the path patterns
+ * that were given from the command line.  We are not
+ * going to write this index out.
+ */
+void overlay_tree_on_cache(const char *tree_name, const char *prefix)
+{
+	struct tree *tree;
+	unsigned char sha1[20];
+	const char **match;
+	struct cache_entry *last_stage0 = NULL;
+	int i;
+
+	if (get_sha1(tree_name, sha1))
+		die("tree-ish %s not found.", tree_name);
+	tree = parse_tree_indirect(sha1);
+	if (!tree)
+		die("bad tree-ish %s", tree_name);
+
+	/* Hoist the unmerged entries up to stage #3 to make room */
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (!ce_stage(ce))
+			continue;
+		ce->ce_flags |= CE_STAGEMASK;
+	}
+
+	if (prefix) {
+		static const char *(matchbuf[2]);
+		matchbuf[0] = prefix;
+		matchbuf[1] = NULL;
+		match = matchbuf;
+	} else
+		match = NULL;
+	if (read_tree(tree, 1, match))
+		die("unable to read tree entries %s", tree_name);
+
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		switch (ce_stage(ce)) {
+		case 0:
+			last_stage0 = ce;
+			/* fallthru */
+		default:
+			continue;
+		case 1:
+			/*
+			 * If there is stage #0 entry for this, we do not
+			 * need to show it.  We use CE_UPDATE bit to mark
+			 * such an entry.
+			 */
+			if (last_stage0 &&
+			    !strcmp(last_stage0->name, ce->name))
+				ce->ce_flags |= CE_UPDATE;
+		}
+	}
+}
+
+int report_path_error(const char *ps_matched, const char **pathspec, int prefix_offset)
+{
+	/*
+	 * Make sure all pathspec matched; otherwise it is an error.
+	 */
+	int num, errors = 0;
+	for (num = 0; pathspec[num]; num++) {
+		int other, found_dup;
+
+		if (ps_matched[num])
+			continue;
+		/*
+		 * The caller might have fed identical pathspec
+		 * twice.  Do not barf on such a mistake.
+		 */
+		for (found_dup = other = 0;
+		     !found_dup && pathspec[other];
+		     other++) {
+			if (other == num || !ps_matched[other])
+				continue;
+			if (!strcmp(pathspec[other], pathspec[num]))
+				/*
+				 * Ok, we have a match already.
+				 */
+				found_dup = 1;
+		}
+		if (found_dup)
+			continue;
+
+		error("pathspec '%s' did not match any file(s) known to git.",
+		      pathspec[num] + prefix_offset);
+		errors++;
+	}
+	return errors;
+}
+
+static const char * const ls_files_usage[] = {
+	"git ls-files [options] [<file>]*",
+	NULL
+};
+
+static int option_parse_z(const struct option *opt,
+			  const char *arg, int unset)
+{
+	line_terminator = unset ? '\n' : '\0';
+
+	return 0;
+}
+
+static int option_parse_exclude(const struct option *opt,
+				const char *arg, int unset)
+{
+	struct exclude_list *list = opt->value;
+
+	exc_given = 1;
+	add_exclude(arg, "", 0, list);
+
+	return 0;
+}
+
+static int option_parse_exclude_from(const struct option *opt,
+				     const char *arg, int unset)
+{
+	struct dir_struct *dir = opt->value;
+
+	exc_given = 1;
+	add_excludes_from_file(dir, arg);
+
+	return 0;
+}
+
+static int option_parse_exclude_standard(const struct option *opt,
+					 const char *arg, int unset)
+{
+	struct dir_struct *dir = opt->value;
+
+	exc_given = 1;
+	setup_standard_excludes(dir);
+
+	return 0;
+}
+
+int cmd_ls_files(int argc, const char **argv, const char *prefix)
+{
+	int require_work_tree = 0, show_tag = 0;
+	struct dir_struct dir;
+	struct option builtin_ls_files_options[] = {
+		{ OPTION_CALLBACK, 'z', NULL, NULL, NULL,
+			"paths are separated with NUL character",
+			PARSE_OPT_NOARG, option_parse_z },
+		OPT_BOOLEAN('t', NULL, &show_tag,
+			"identify the file status with tags"),
+		OPT_BOOLEAN('v', NULL, &show_valid_bit,
+			"use lowercase letters for 'assume unchanged' files"),
+		OPT_BOOLEAN('c', "cached", &show_cached,
+			"show cached files in the output (default)"),
+		OPT_BOOLEAN('d', "deleted", &show_deleted,
+			"show deleted files in the output"),
+		OPT_BOOLEAN('m', "modified", &show_modified,
+			"show modified files in the output"),
+		OPT_BOOLEAN('o', "others", &show_others,
+			"show other files in the output"),
+		OPT_BIT('i', "ignored", &dir.flags,
+			"show ignored files in the output",
+			DIR_SHOW_IGNORED),
+		OPT_BOOLEAN('s', "stage", &show_stage,
+			"show staged contents' object name in the output"),
+		OPT_BOOLEAN('k', "killed", &show_killed,
+			"show files on the filesystem that need to be removed"),
+		OPT_BIT(0, "directory", &dir.flags,
+			"show 'other' directories' name only",
+			DIR_SHOW_OTHER_DIRECTORIES),
+		OPT_NEGBIT(0, "empty-directory", &dir.flags,
+			"don't show empty directories",
+			DIR_HIDE_EMPTY_DIRECTORIES),
+		OPT_BOOLEAN('u', "unmerged", &show_unmerged,
+			"show unmerged files in the output"),
+		OPT_BOOLEAN(0, "resolve-undo", &show_resolve_undo,
+			    "show resolve-undo information"),
+		{ OPTION_CALLBACK, 'x', "exclude", &dir.exclude_list[EXC_CMDL], "pattern",
+			"skip files matching pattern",
+			0, option_parse_exclude },
+		{ OPTION_CALLBACK, 'X', "exclude-from", &dir, "file",
+			"exclude patterns are read from <file>",
+			0, option_parse_exclude_from },
+		OPT_STRING(0, "exclude-per-directory", &dir.exclude_per_dir, "file",
+			"read additional per-directory exclude patterns in <file>"),
+		{ OPTION_CALLBACK, 0, "exclude-standard", &dir, NULL,
+			"add the standard git exclusions",
+			PARSE_OPT_NOARG, option_parse_exclude_standard },
+		{ OPTION_SET_INT, 0, "full-name", &prefix_offset, NULL,
+			"make the output relative to the project top directory",
+			PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL },
+		OPT_BOOLEAN(0, "error-unmatch", &error_unmatch,
+			"if any <file> is not in the index, treat this as an error"),
+		OPT_STRING(0, "with-tree", &with_tree, "tree-ish",
+			"pretend that paths removed since <tree-ish> are still present"),
+		OPT__ABBREV(&abbrev),
+		OPT_END()
+	};
+
+	memset(&dir, 0, sizeof(dir));
+	if (prefix)
+		prefix_offset = strlen(prefix);
+	git_config(git_default_config, NULL);
+
+	if (read_cache() < 0)
+		die("index file corrupt");
+
+	argc = parse_options(argc, argv, prefix, builtin_ls_files_options,
+			ls_files_usage, 0);
+	if (show_tag || show_valid_bit) {
+		tag_cached = "H ";
+		tag_unmerged = "M ";
+		tag_removed = "R ";
+		tag_modified = "C ";
+		tag_other = "? ";
+		tag_killed = "K ";
+		tag_skip_worktree = "S ";
+		tag_resolve_undo = "U ";
+	}
+	if (show_modified || show_others || show_deleted || (dir.flags & DIR_SHOW_IGNORED) || show_killed)
+		require_work_tree = 1;
+	if (show_unmerged)
+		/*
+		 * There's no point in showing unmerged unless
+		 * you also show the stage information.
+		 */
+		show_stage = 1;
+	if (dir.exclude_per_dir)
+		exc_given = 1;
+
+	if (require_work_tree && !is_inside_work_tree())
+		setup_work_tree();
+
+	pathspec = get_pathspec(prefix, argv);
+
+	/* be nice with submodule paths ending in a slash */
+	if (pathspec)
+		strip_trailing_slash_from_submodules();
+
+	/* Verify that the pathspec matches the prefix */
+	if (pathspec)
+		prefix = verify_pathspec(prefix);
+
+	/* Treat unmatching pathspec elements as errors */
+	if (pathspec && error_unmatch) {
+		int num;
+		for (num = 0; pathspec[num]; num++)
+			;
+		ps_matched = xcalloc(1, num);
+	}
+
+	if ((dir.flags & DIR_SHOW_IGNORED) && !exc_given)
+		die("ls-files --ignored needs some exclude pattern");
+
+	/* With no flags, we default to showing the cached files */
+	if (!(show_stage | show_deleted | show_others | show_unmerged |
+	      show_killed | show_modified | show_resolve_undo))
+		show_cached = 1;
+
+	if (prefix)
+		prune_cache(prefix);
+	if (with_tree) {
+		/*
+		 * Basic sanity check; show-stages and show-unmerged
+		 * would not make any sense with this option.
+		 */
+		if (show_stage || show_unmerged)
+			die("ls-files --with-tree is incompatible with -s or -u");
+		overlay_tree_on_cache(with_tree, prefix);
+	}
+	show_files(&dir, prefix);
+	if (show_resolve_undo)
+		show_ru_info(prefix);
+
+	if (ps_matched) {
+		int bad;
+		bad = report_path_error(ps_matched, pathspec, prefix_offset);
+		if (bad)
+			fprintf(stderr, "Did you forget to 'git add'?\n");
+
+		return bad ? 1 : 0;
+	}
+
+	return 0;
+}
diff --git a/builtin/ls-remote.c b/builtin/ls-remote.c
new file mode 100644
index 0000000..70f5622
--- /dev/null
+++ b/builtin/ls-remote.c
@@ -0,0 +1,107 @@
+#include "builtin.h"
+#include "cache.h"
+#include "transport.h"
+#include "remote.h"
+
+static const char ls_remote_usage[] =
+"git ls-remote [--heads] [--tags]  [-u <exec> | --upload-pack <exec>] <repository> <refs>...";
+
+/*
+ * Is there one among the list of patterns that match the tail part
+ * of the path?
+ */
+static int tail_match(const char **pattern, const char *path)
+{
+	const char *p;
+	char pathbuf[PATH_MAX];
+
+	if (!pattern)
+		return 1; /* no restriction */
+
+	if (snprintf(pathbuf, sizeof(pathbuf), "/%s", path) > sizeof(pathbuf))
+		return error("insanely long ref %.*s...", 20, path);
+	while ((p = *(pattern++)) != NULL) {
+		if (!fnmatch(p, pathbuf, 0))
+			return 1;
+	}
+	return 0;
+}
+
+int cmd_ls_remote(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	const char *dest = NULL;
+	int nongit;
+	unsigned flags = 0;
+	const char *uploadpack = NULL;
+	const char **pattern = NULL;
+
+	struct remote *remote;
+	struct transport *transport;
+	const struct ref *ref;
+
+	setup_git_directory_gently(&nongit);
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (*arg == '-') {
+			if (!prefixcmp(arg, "--upload-pack=")) {
+				uploadpack = arg + 14;
+				continue;
+			}
+			if (!prefixcmp(arg, "--exec=")) {
+				uploadpack = arg + 7;
+				continue;
+			}
+			if (!strcmp("--tags", arg) || !strcmp("-t", arg)) {
+				flags |= REF_TAGS;
+				continue;
+			}
+			if (!strcmp("--heads", arg) || !strcmp("-h", arg)) {
+				flags |= REF_HEADS;
+				continue;
+			}
+			if (!strcmp("--refs", arg)) {
+				flags |= REF_NORMAL;
+				continue;
+			}
+			usage(ls_remote_usage);
+		}
+		dest = arg;
+		i++;
+		break;
+	}
+
+	if (!dest)
+		usage(ls_remote_usage);
+
+	if (argv[i]) {
+		int j;
+		pattern = xcalloc(sizeof(const char *), argc - i + 1);
+		for (j = i; j < argc; j++) {
+			int len = strlen(argv[j]);
+			char *p = xmalloc(len + 3);
+			sprintf(p, "*/%s", argv[j]);
+			pattern[j - i] = p;
+		}
+	}
+	remote = remote_get(dest);
+	if (!remote->url_nr)
+		die("remote %s has no configured URL", dest);
+	transport = transport_get(remote, NULL);
+	if (uploadpack != NULL)
+		transport_set_option(transport, TRANS_OPT_UPLOADPACK, uploadpack);
+
+	ref = transport_get_remote_refs(transport);
+	if (transport_disconnect(transport))
+		return 1;
+	for ( ; ref; ref = ref->next) {
+		if (!check_ref_type(ref, flags))
+			continue;
+		if (!tail_match(pattern, ref->name))
+			continue;
+		printf("%s	%s\n", sha1_to_hex(ref->old_sha1), ref->name);
+	}
+	return 0;
+}
diff --git a/builtin/ls-tree.c b/builtin/ls-tree.c
new file mode 100644
index 0000000..4484185
--- /dev/null
+++ b/builtin/ls-tree.c
@@ -0,0 +1,176 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "blob.h"
+#include "tree.h"
+#include "commit.h"
+#include "quote.h"
+#include "builtin.h"
+#include "parse-options.h"
+
+static int line_termination = '\n';
+#define LS_RECURSIVE 1
+#define LS_TREE_ONLY 2
+#define LS_SHOW_TREES 4
+#define LS_NAME_ONLY 8
+#define LS_SHOW_SIZE 16
+static int abbrev;
+static int ls_options;
+static const char **pathspec;
+static int chomp_prefix;
+static const char *ls_tree_prefix;
+
+static const  char * const ls_tree_usage[] = {
+	"git ls-tree [<options>] <tree-ish> [path...]",
+	NULL
+};
+
+static int show_recursive(const char *base, int baselen, const char *pathname)
+{
+	const char **s;
+
+	if (ls_options & LS_RECURSIVE)
+		return 1;
+
+	s = pathspec;
+	if (!s)
+		return 0;
+
+	for (;;) {
+		const char *spec = *s++;
+		int len, speclen;
+
+		if (!spec)
+			return 0;
+		if (strncmp(base, spec, baselen))
+			continue;
+		len = strlen(pathname);
+		spec += baselen;
+		speclen = strlen(spec);
+		if (speclen <= len)
+			continue;
+		if (memcmp(pathname, spec, len))
+			continue;
+		return 1;
+	}
+}
+
+static int show_tree(const unsigned char *sha1, const char *base, int baselen,
+		const char *pathname, unsigned mode, int stage, void *context)
+{
+	int retval = 0;
+	const char *type = blob_type;
+
+	if (S_ISGITLINK(mode)) {
+		/*
+		 * Maybe we want to have some recursive version here?
+		 *
+		 * Something similar to this incomplete example:
+		 *
+		if (show_subprojects(base, baselen, pathname))
+			retval = READ_TREE_RECURSIVE;
+		 *
+		 */
+		type = commit_type;
+	} else if (S_ISDIR(mode)) {
+		if (show_recursive(base, baselen, pathname)) {
+			retval = READ_TREE_RECURSIVE;
+			if (!(ls_options & LS_SHOW_TREES))
+				return retval;
+		}
+		type = tree_type;
+	}
+	else if (ls_options & LS_TREE_ONLY)
+		return 0;
+
+	if (chomp_prefix &&
+	    (baselen < chomp_prefix || memcmp(ls_tree_prefix, base, chomp_prefix)))
+		return 0;
+
+	if (!(ls_options & LS_NAME_ONLY)) {
+		if (ls_options & LS_SHOW_SIZE) {
+			char size_text[24];
+			if (!strcmp(type, blob_type)) {
+				unsigned long size;
+				if (sha1_object_info(sha1, &size) == OBJ_BAD)
+					strcpy(size_text, "BAD");
+				else
+					snprintf(size_text, sizeof(size_text),
+						 "%lu", size);
+			} else
+				strcpy(size_text, "-");
+			printf("%06o %s %s %7s\t", mode, type,
+			       abbrev ? find_unique_abbrev(sha1, abbrev)
+				      : sha1_to_hex(sha1),
+			       size_text);
+		} else
+			printf("%06o %s %s\t", mode, type,
+			       abbrev ? find_unique_abbrev(sha1, abbrev)
+			              : sha1_to_hex(sha1));
+	}
+	write_name_quotedpfx(base + chomp_prefix, baselen - chomp_prefix,
+			  pathname, stdout, line_termination);
+	return retval;
+}
+
+int cmd_ls_tree(int argc, const char **argv, const char *prefix)
+{
+	unsigned char sha1[20];
+	struct tree *tree;
+	int full_tree = 0;
+	const struct option ls_tree_options[] = {
+		OPT_BIT('d', NULL, &ls_options, "only show trees",
+			LS_TREE_ONLY),
+		OPT_BIT('r', NULL, &ls_options, "recurse into subtrees",
+			LS_RECURSIVE),
+		OPT_BIT('t', NULL, &ls_options, "show trees when recursing",
+			LS_SHOW_TREES),
+		OPT_SET_INT('z', NULL, &line_termination,
+			    "terminate entries with NUL byte", 0),
+		OPT_BIT('l', "long", &ls_options, "include object size",
+			LS_SHOW_SIZE),
+		OPT_BIT(0, "name-only", &ls_options, "list only filenames",
+			LS_NAME_ONLY),
+		OPT_BIT(0, "name-status", &ls_options, "list only filenames",
+			LS_NAME_ONLY),
+		OPT_SET_INT(0, "full-name", &chomp_prefix,
+			    "use full path names", 0),
+		OPT_BOOLEAN(0, "full-tree", &full_tree,
+			    "list entire tree; not just current directory "
+			    "(implies --full-name)"),
+		OPT__ABBREV(&abbrev),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+	ls_tree_prefix = prefix;
+	if (prefix && *prefix)
+		chomp_prefix = strlen(prefix);
+
+	argc = parse_options(argc, argv, prefix, ls_tree_options,
+			     ls_tree_usage, 0);
+	if (full_tree) {
+		ls_tree_prefix = prefix = NULL;
+		chomp_prefix = 0;
+	}
+	/* -d -r should imply -t, but -d by itself should not have to. */
+	if ( (LS_TREE_ONLY|LS_RECURSIVE) ==
+	    ((LS_TREE_ONLY|LS_RECURSIVE) & ls_options))
+		ls_options |= LS_SHOW_TREES;
+
+	if (argc < 1)
+		usage_with_options(ls_tree_usage, ls_tree_options);
+	if (get_sha1(argv[0], sha1))
+		die("Not a valid object name %s", argv[0]);
+
+	pathspec = get_pathspec(prefix, argv + 1);
+	tree = parse_tree_indirect(sha1);
+	if (!tree)
+		die("not a tree object");
+	read_tree_recursive(tree, "", 0, 0, pathspec, show_tree, NULL);
+
+	return 0;
+}
diff --git a/builtin/mailinfo.c b/builtin/mailinfo.c
new file mode 100644
index 0000000..ce2ef6b
--- /dev/null
+++ b/builtin/mailinfo.c
@@ -0,0 +1,1063 @@
+/*
+ * Another stupid program, this one parsing the headers of an
+ * email to figure out authorship and subject
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "utf8.h"
+#include "strbuf.h"
+
+static FILE *cmitmsg, *patchfile, *fin, *fout;
+
+static int keep_subject;
+static int keep_non_patch_brackets_in_subject;
+static const char *metainfo_charset;
+static struct strbuf line = STRBUF_INIT;
+static struct strbuf name = STRBUF_INIT;
+static struct strbuf email = STRBUF_INIT;
+
+static enum  {
+	TE_DONTCARE, TE_QP, TE_BASE64,
+} transfer_encoding;
+static enum  {
+	TYPE_TEXT, TYPE_OTHER,
+} message_type;
+
+static struct strbuf charset = STRBUF_INIT;
+static int patch_lines;
+static struct strbuf **p_hdr_data, **s_hdr_data;
+static int use_scissors;
+static int use_inbody_headers = 1;
+
+#define MAX_HDR_PARSED 10
+#define MAX_BOUNDARIES 5
+
+static void cleanup_space(struct strbuf *sb);
+
+
+static void get_sane_name(struct strbuf *out, struct strbuf *name, struct strbuf *email)
+{
+	struct strbuf *src = name;
+	if (name->len < 3 || 60 < name->len || strchr(name->buf, '@') ||
+		strchr(name->buf, '<') || strchr(name->buf, '>'))
+		src = email;
+	else if (name == out)
+		return;
+	strbuf_reset(out);
+	strbuf_addbuf(out, src);
+}
+
+static void parse_bogus_from(const struct strbuf *line)
+{
+	/* John Doe <johndoe> */
+
+	char *bra, *ket;
+	/* This is fallback, so do not bother if we already have an
+	 * e-mail address.
+	 */
+	if (email.len)
+		return;
+
+	bra = strchr(line->buf, '<');
+	if (!bra)
+		return;
+	ket = strchr(bra, '>');
+	if (!ket)
+		return;
+
+	strbuf_reset(&email);
+	strbuf_add(&email, bra + 1, ket - bra - 1);
+
+	strbuf_reset(&name);
+	strbuf_add(&name, line->buf, bra - line->buf);
+	strbuf_trim(&name);
+	get_sane_name(&name, &name, &email);
+}
+
+static void handle_from(const struct strbuf *from)
+{
+	char *at;
+	size_t el;
+	struct strbuf f;
+
+	strbuf_init(&f, from->len);
+	strbuf_addbuf(&f, from);
+
+	at = strchr(f.buf, '@');
+	if (!at) {
+		parse_bogus_from(from);
+		return;
+	}
+
+	/*
+	 * If we already have one email, don't take any confusing lines
+	 */
+	if (email.len && strchr(at + 1, '@')) {
+		strbuf_release(&f);
+		return;
+	}
+
+	/* Pick up the string around '@', possibly delimited with <>
+	 * pair; that is the email part.
+	 */
+	while (at > f.buf) {
+		char c = at[-1];
+		if (isspace(c))
+			break;
+		if (c == '<') {
+			at[-1] = ' ';
+			break;
+		}
+		at--;
+	}
+	el = strcspn(at, " \n\t\r\v\f>");
+	strbuf_reset(&email);
+	strbuf_add(&email, at, el);
+	strbuf_remove(&f, at - f.buf, el + (at[el] ? 1 : 0));
+
+	/* The remainder is name.  It could be
+	 *
+	 * - "John Doe <john.doe@xz>"			(a), or
+	 * - "john.doe@xz (John Doe)"			(b), or
+	 * - "John (zzz) Doe <john.doe@xz> (Comment)"	(c)
+	 *
+	 * but we have removed the email part, so
+	 *
+	 * - remove extra spaces which could stay after email (case 'c'), and
+	 * - trim from both ends, possibly removing the () pair at the end
+	 *   (cases 'a' and 'b').
+	 */
+	cleanup_space(&f);
+	strbuf_trim(&f);
+	if (f.buf[0] == '(' && f.len && f.buf[f.len - 1] == ')') {
+		strbuf_remove(&f, 0, 1);
+		strbuf_setlen(&f, f.len - 1);
+	}
+
+	get_sane_name(&name, &f, &email);
+	strbuf_release(&f);
+}
+
+static void handle_header(struct strbuf **out, const struct strbuf *line)
+{
+	if (!*out) {
+		*out = xmalloc(sizeof(struct strbuf));
+		strbuf_init(*out, line->len);
+	} else
+		strbuf_reset(*out);
+
+	strbuf_addbuf(*out, line);
+}
+
+/* NOTE NOTE NOTE.  We do not claim we do full MIME.  We just attempt
+ * to have enough heuristics to grok MIME encoded patches often found
+ * on our mailing lists.  For example, we do not even treat header lines
+ * case insensitively.
+ */
+
+static int slurp_attr(const char *line, const char *name, struct strbuf *attr)
+{
+	const char *ends, *ap = strcasestr(line, name);
+	size_t sz;
+
+	if (!ap) {
+		strbuf_setlen(attr, 0);
+		return 0;
+	}
+	ap += strlen(name);
+	if (*ap == '"') {
+		ap++;
+		ends = "\"";
+	}
+	else
+		ends = "; \t";
+	sz = strcspn(ap, ends);
+	strbuf_add(attr, ap, sz);
+	return 1;
+}
+
+static struct strbuf *content[MAX_BOUNDARIES];
+
+static struct strbuf **content_top = content;
+
+static void handle_content_type(struct strbuf *line)
+{
+	struct strbuf *boundary = xmalloc(sizeof(struct strbuf));
+	strbuf_init(boundary, line->len);
+
+	if (!strcasestr(line->buf, "text/"))
+		 message_type = TYPE_OTHER;
+	if (slurp_attr(line->buf, "boundary=", boundary)) {
+		strbuf_insert(boundary, 0, "--", 2);
+		if (++content_top > &content[MAX_BOUNDARIES]) {
+			fprintf(stderr, "Too many boundaries to handle\n");
+			exit(1);
+		}
+		*content_top = boundary;
+		boundary = NULL;
+	}
+	slurp_attr(line->buf, "charset=", &charset);
+
+	if (boundary) {
+		strbuf_release(boundary);
+		free(boundary);
+	}
+}
+
+static void handle_content_transfer_encoding(const struct strbuf *line)
+{
+	if (strcasestr(line->buf, "base64"))
+		transfer_encoding = TE_BASE64;
+	else if (strcasestr(line->buf, "quoted-printable"))
+		transfer_encoding = TE_QP;
+	else
+		transfer_encoding = TE_DONTCARE;
+}
+
+static int is_multipart_boundary(const struct strbuf *line)
+{
+	return (((*content_top)->len <= line->len) &&
+		!memcmp(line->buf, (*content_top)->buf, (*content_top)->len));
+}
+
+static void cleanup_subject(struct strbuf *subject)
+{
+	size_t at = 0;
+
+	while (at < subject->len) {
+		char *pos;
+		size_t remove;
+
+		switch (subject->buf[at]) {
+		case 'r': case 'R':
+			if (subject->len <= at + 3)
+				break;
+			if (!memcmp(subject->buf + at + 1, "e:", 2)) {
+				strbuf_remove(subject, at, 3);
+				continue;
+			}
+			at++;
+			break;
+		case ' ': case '\t': case ':':
+			strbuf_remove(subject, at, 1);
+			continue;
+		case '[':
+			pos = strchr(subject->buf + at, ']');
+			if (!pos)
+				break;
+			remove = pos - subject->buf + at + 1;
+			if (!keep_non_patch_brackets_in_subject ||
+			    (7 <= remove &&
+			     memmem(subject->buf + at, remove, "PATCH", 5)))
+				strbuf_remove(subject, at, remove);
+			else
+				at += remove;
+			continue;
+		}
+		break;
+	}
+	strbuf_trim(subject);
+}
+
+static void cleanup_space(struct strbuf *sb)
+{
+	size_t pos, cnt;
+	for (pos = 0; pos < sb->len; pos++) {
+		if (isspace(sb->buf[pos])) {
+			sb->buf[pos] = ' ';
+			for (cnt = 0; isspace(sb->buf[pos + cnt + 1]); cnt++);
+			strbuf_remove(sb, pos + 1, cnt);
+		}
+	}
+}
+
+static void decode_header(struct strbuf *line);
+static const char *header[MAX_HDR_PARSED] = {
+	"From","Subject","Date",
+};
+
+static inline int cmp_header(const struct strbuf *line, const char *hdr)
+{
+	int len = strlen(hdr);
+	return !strncasecmp(line->buf, hdr, len) && line->len > len &&
+			line->buf[len] == ':' && isspace(line->buf[len + 1]);
+}
+
+static int check_header(const struct strbuf *line,
+				struct strbuf *hdr_data[], int overwrite)
+{
+	int i, ret = 0, len;
+	struct strbuf sb = STRBUF_INIT;
+	/* search for the interesting parts */
+	for (i = 0; header[i]; i++) {
+		int len = strlen(header[i]);
+		if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) {
+			/* Unwrap inline B and Q encoding, and optionally
+			 * normalize the meta information to utf8.
+			 */
+			strbuf_add(&sb, line->buf + len + 2, line->len - len - 2);
+			decode_header(&sb);
+			handle_header(&hdr_data[i], &sb);
+			ret = 1;
+			goto check_header_out;
+		}
+	}
+
+	/* Content stuff */
+	if (cmp_header(line, "Content-Type")) {
+		len = strlen("Content-Type: ");
+		strbuf_add(&sb, line->buf + len, line->len - len);
+		decode_header(&sb);
+		strbuf_insert(&sb, 0, "Content-Type: ", len);
+		handle_content_type(&sb);
+		ret = 1;
+		goto check_header_out;
+	}
+	if (cmp_header(line, "Content-Transfer-Encoding")) {
+		len = strlen("Content-Transfer-Encoding: ");
+		strbuf_add(&sb, line->buf + len, line->len - len);
+		decode_header(&sb);
+		handle_content_transfer_encoding(&sb);
+		ret = 1;
+		goto check_header_out;
+	}
+
+	/* for inbody stuff */
+	if (!prefixcmp(line->buf, ">From") && isspace(line->buf[5])) {
+		ret = 1; /* Should this return 0? */
+		goto check_header_out;
+	}
+	if (!prefixcmp(line->buf, "[PATCH]") && isspace(line->buf[7])) {
+		for (i = 0; header[i]; i++) {
+			if (!memcmp("Subject", header[i], 7)) {
+				handle_header(&hdr_data[i], line);
+				ret = 1;
+				goto check_header_out;
+			}
+		}
+	}
+
+check_header_out:
+	strbuf_release(&sb);
+	return ret;
+}
+
+static int is_rfc2822_header(const struct strbuf *line)
+{
+	/*
+	 * The section that defines the loosest possible
+	 * field name is "3.6.8 Optional fields".
+	 *
+	 * optional-field = field-name ":" unstructured CRLF
+	 * field-name = 1*ftext
+	 * ftext = %d33-57 / %59-126
+	 */
+	int ch;
+	char *cp = line->buf;
+
+	/* Count mbox From headers as headers */
+	if (!prefixcmp(cp, "From ") || !prefixcmp(cp, ">From "))
+		return 1;
+
+	while ((ch = *cp++)) {
+		if (ch == ':')
+			return 1;
+		if ((33 <= ch && ch <= 57) ||
+		    (59 <= ch && ch <= 126))
+			continue;
+		break;
+	}
+	return 0;
+}
+
+static int read_one_header_line(struct strbuf *line, FILE *in)
+{
+	/* Get the first part of the line. */
+	if (strbuf_getline(line, in, '\n'))
+		return 0;
+
+	/*
+	 * Is it an empty line or not a valid rfc2822 header?
+	 * If so, stop here, and return false ("not a header")
+	 */
+	strbuf_rtrim(line);
+	if (!line->len || !is_rfc2822_header(line)) {
+		/* Re-add the newline */
+		strbuf_addch(line, '\n');
+		return 0;
+	}
+
+	/*
+	 * Now we need to eat all the continuation lines..
+	 * Yuck, 2822 header "folding"
+	 */
+	for (;;) {
+		int peek;
+		struct strbuf continuation = STRBUF_INIT;
+
+		peek = fgetc(in); ungetc(peek, in);
+		if (peek != ' ' && peek != '\t')
+			break;
+		if (strbuf_getline(&continuation, in, '\n'))
+			break;
+		continuation.buf[0] = '\n';
+		strbuf_rtrim(&continuation);
+		strbuf_addbuf(line, &continuation);
+	}
+
+	return 1;
+}
+
+static struct strbuf *decode_q_segment(const struct strbuf *q_seg, int rfc2047)
+{
+	const char *in = q_seg->buf;
+	int c;
+	struct strbuf *out = xmalloc(sizeof(struct strbuf));
+	strbuf_init(out, q_seg->len);
+
+	while ((c = *in++) != 0) {
+		if (c == '=') {
+			int d = *in++;
+			if (d == '\n' || !d)
+				break; /* drop trailing newline */
+			strbuf_addch(out, (hexval(d) << 4) | hexval(*in++));
+			continue;
+		}
+		if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
+			c = 0x20;
+		strbuf_addch(out, c);
+	}
+	return out;
+}
+
+static struct strbuf *decode_b_segment(const struct strbuf *b_seg)
+{
+	/* Decode in..ep, possibly in-place to ot */
+	int c, pos = 0, acc = 0;
+	const char *in = b_seg->buf;
+	struct strbuf *out = xmalloc(sizeof(struct strbuf));
+	strbuf_init(out, b_seg->len);
+
+	while ((c = *in++) != 0) {
+		if (c == '+')
+			c = 62;
+		else if (c == '/')
+			c = 63;
+		else if ('A' <= c && c <= 'Z')
+			c -= 'A';
+		else if ('a' <= c && c <= 'z')
+			c -= 'a' - 26;
+		else if ('0' <= c && c <= '9')
+			c -= '0' - 52;
+		else
+			continue; /* garbage */
+		switch (pos++) {
+		case 0:
+			acc = (c << 2);
+			break;
+		case 1:
+			strbuf_addch(out, (acc | (c >> 4)));
+			acc = (c & 15) << 4;
+			break;
+		case 2:
+			strbuf_addch(out, (acc | (c >> 2)));
+			acc = (c & 3) << 6;
+			break;
+		case 3:
+			strbuf_addch(out, (acc | c));
+			acc = pos = 0;
+			break;
+		}
+	}
+	return out;
+}
+
+/*
+ * When there is no known charset, guess.
+ *
+ * Right now we assume that if the target is UTF-8 (the default),
+ * and it already looks like UTF-8 (which includes US-ASCII as its
+ * subset, of course) then that is what it is and there is nothing
+ * to do.
+ *
+ * Otherwise, we default to assuming it is Latin1 for historical
+ * reasons.
+ */
+static const char *guess_charset(const struct strbuf *line, const char *target_charset)
+{
+	if (is_encoding_utf8(target_charset)) {
+		if (is_utf8(line->buf))
+			return NULL;
+	}
+	return "ISO8859-1";
+}
+
+static void convert_to_utf8(struct strbuf *line, const char *charset)
+{
+	char *out;
+
+	if (!charset || !*charset) {
+		charset = guess_charset(line, metainfo_charset);
+		if (!charset)
+			return;
+	}
+
+	if (!strcasecmp(metainfo_charset, charset))
+		return;
+	out = reencode_string(line->buf, metainfo_charset, charset);
+	if (!out)
+		die("cannot convert from %s to %s",
+		    charset, metainfo_charset);
+	strbuf_attach(line, out, strlen(out), strlen(out));
+}
+
+static int decode_header_bq(struct strbuf *it)
+{
+	char *in, *ep, *cp;
+	struct strbuf outbuf = STRBUF_INIT, *dec;
+	struct strbuf charset_q = STRBUF_INIT, piecebuf = STRBUF_INIT;
+	int rfc2047 = 0;
+
+	in = it->buf;
+	while (in - it->buf <= it->len && (ep = strstr(in, "=?")) != NULL) {
+		int encoding;
+		strbuf_reset(&charset_q);
+		strbuf_reset(&piecebuf);
+		rfc2047 = 1;
+
+		if (in != ep) {
+			/*
+			 * We are about to process an encoded-word
+			 * that begins at ep, but there is something
+			 * before the encoded word.
+			 */
+			char *scan;
+			for (scan = in; scan < ep; scan++)
+				if (!isspace(*scan))
+					break;
+
+			if (scan != ep || in == it->buf) {
+				/*
+				 * We should not lose that "something",
+				 * unless we have just processed an
+				 * encoded-word, and there is only LWS
+				 * before the one we are about to process.
+				 */
+				strbuf_add(&outbuf, in, ep - in);
+			}
+		}
+		/* E.g.
+		 * ep : "=?iso-2022-jp?B?GyR...?= foo"
+		 * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
+		 */
+		ep += 2;
+
+		if (ep - it->buf >= it->len || !(cp = strchr(ep, '?')))
+			goto decode_header_bq_out;
+
+		if (cp + 3 - it->buf > it->len)
+			goto decode_header_bq_out;
+		strbuf_add(&charset_q, ep, cp - ep);
+
+		encoding = cp[1];
+		if (!encoding || cp[2] != '?')
+			goto decode_header_bq_out;
+		ep = strstr(cp + 3, "?=");
+		if (!ep)
+			goto decode_header_bq_out;
+		strbuf_add(&piecebuf, cp + 3, ep - cp - 3);
+		switch (tolower(encoding)) {
+		default:
+			goto decode_header_bq_out;
+		case 'b':
+			dec = decode_b_segment(&piecebuf);
+			break;
+		case 'q':
+			dec = decode_q_segment(&piecebuf, 1);
+			break;
+		}
+		if (metainfo_charset)
+			convert_to_utf8(dec, charset_q.buf);
+
+		strbuf_addbuf(&outbuf, dec);
+		strbuf_release(dec);
+		free(dec);
+		in = ep + 2;
+	}
+	strbuf_addstr(&outbuf, in);
+	strbuf_reset(it);
+	strbuf_addbuf(it, &outbuf);
+decode_header_bq_out:
+	strbuf_release(&outbuf);
+	strbuf_release(&charset_q);
+	strbuf_release(&piecebuf);
+	return rfc2047;
+}
+
+static void decode_header(struct strbuf *it)
+{
+	if (decode_header_bq(it))
+		return;
+	/* otherwise "it" is a straight copy of the input.
+	 * This can be binary guck but there is no charset specified.
+	 */
+	if (metainfo_charset)
+		convert_to_utf8(it, "");
+}
+
+static void decode_transfer_encoding(struct strbuf *line)
+{
+	struct strbuf *ret;
+
+	switch (transfer_encoding) {
+	case TE_QP:
+		ret = decode_q_segment(line, 0);
+		break;
+	case TE_BASE64:
+		ret = decode_b_segment(line);
+		break;
+	case TE_DONTCARE:
+	default:
+		return;
+	}
+	strbuf_reset(line);
+	strbuf_addbuf(line, ret);
+	strbuf_release(ret);
+	free(ret);
+}
+
+static void handle_filter(struct strbuf *line);
+
+static int find_boundary(void)
+{
+	while (!strbuf_getline(&line, fin, '\n')) {
+		if (*content_top && is_multipart_boundary(&line))
+			return 1;
+	}
+	return 0;
+}
+
+static int handle_boundary(void)
+{
+	struct strbuf newline = STRBUF_INIT;
+
+	strbuf_addch(&newline, '\n');
+again:
+	if (line.len >= (*content_top)->len + 2 &&
+	    !memcmp(line.buf + (*content_top)->len, "--", 2)) {
+		/* we hit an end boundary */
+		/* pop the current boundary off the stack */
+		strbuf_release(*content_top);
+		free(*content_top);
+		*content_top = NULL;
+
+		/* technically won't happen as is_multipart_boundary()
+		   will fail first.  But just in case..
+		 */
+		if (--content_top < content) {
+			fprintf(stderr, "Detected mismatched boundaries, "
+					"can't recover\n");
+			exit(1);
+		}
+		handle_filter(&newline);
+		strbuf_release(&newline);
+
+		/* skip to the next boundary */
+		if (!find_boundary())
+			return 0;
+		goto again;
+	}
+
+	/* set some defaults */
+	transfer_encoding = TE_DONTCARE;
+	strbuf_reset(&charset);
+	message_type = TYPE_TEXT;
+
+	/* slurp in this section's info */
+	while (read_one_header_line(&line, fin))
+		check_header(&line, p_hdr_data, 0);
+
+	strbuf_release(&newline);
+	/* replenish line */
+	if (strbuf_getline(&line, fin, '\n'))
+		return 0;
+	strbuf_addch(&line, '\n');
+	return 1;
+}
+
+static inline int patchbreak(const struct strbuf *line)
+{
+	size_t i;
+
+	/* Beginning of a "diff -" header? */
+	if (!prefixcmp(line->buf, "diff -"))
+		return 1;
+
+	/* CVS "Index: " line? */
+	if (!prefixcmp(line->buf, "Index: "))
+		return 1;
+
+	/*
+	 * "--- <filename>" starts patches without headers
+	 * "---<sp>*" is a manual separator
+	 */
+	if (line->len < 4)
+		return 0;
+
+	if (!prefixcmp(line->buf, "---")) {
+		/* space followed by a filename? */
+		if (line->buf[3] == ' ' && !isspace(line->buf[4]))
+			return 1;
+		/* Just whitespace? */
+		for (i = 3; i < line->len; i++) {
+			unsigned char c = line->buf[i];
+			if (c == '\n')
+				return 1;
+			if (!isspace(c))
+				break;
+		}
+		return 0;
+	}
+	return 0;
+}
+
+static int is_scissors_line(const struct strbuf *line)
+{
+	size_t i, len = line->len;
+	int scissors = 0, gap = 0;
+	int first_nonblank = -1;
+	int last_nonblank = 0, visible, perforation = 0, in_perforation = 0;
+	const char *buf = line->buf;
+
+	for (i = 0; i < len; i++) {
+		if (isspace(buf[i])) {
+			if (in_perforation) {
+				perforation++;
+				gap++;
+			}
+			continue;
+		}
+		last_nonblank = i;
+		if (first_nonblank < 0)
+			first_nonblank = i;
+		if (buf[i] == '-') {
+			in_perforation = 1;
+			perforation++;
+			continue;
+		}
+		if (i + 1 < len &&
+		    (!memcmp(buf + i, ">8", 2) || !memcmp(buf + i, "8<", 2))) {
+			in_perforation = 1;
+			perforation += 2;
+			scissors += 2;
+			i++;
+			continue;
+		}
+		in_perforation = 0;
+	}
+
+	/*
+	 * The mark must be at least 8 bytes long (e.g. "-- >8 --").
+	 * Even though there can be arbitrary cruft on the same line
+	 * (e.g. "cut here"), in order to avoid misidentification, the
+	 * perforation must occupy more than a third of the visible
+	 * width of the line, and dashes and scissors must occupy more
+	 * than half of the perforation.
+	 */
+
+	visible = last_nonblank - first_nonblank + 1;
+	return (scissors && 8 <= visible &&
+		visible < perforation * 3 &&
+		gap * 2 < perforation);
+}
+
+static int handle_commit_msg(struct strbuf *line)
+{
+	static int still_looking = 1;
+
+	if (!cmitmsg)
+		return 0;
+
+	if (still_looking) {
+		if (!line->len || (line->len == 1 && line->buf[0] == '\n'))
+			return 0;
+	}
+
+	if (use_inbody_headers && still_looking) {
+		still_looking = check_header(line, s_hdr_data, 0);
+		if (still_looking)
+			return 0;
+	} else
+		/* Only trim the first (blank) line of the commit message
+		 * when ignoring in-body headers.
+		 */
+		still_looking = 0;
+
+	/* normalize the log message to UTF-8. */
+	if (metainfo_charset)
+		convert_to_utf8(line, charset.buf);
+
+	if (use_scissors && is_scissors_line(line)) {
+		int i;
+		if (fseek(cmitmsg, 0L, SEEK_SET))
+			die_errno("Could not rewind output message file");
+		if (ftruncate(fileno(cmitmsg), 0))
+			die_errno("Could not truncate output message file at scissors");
+		still_looking = 1;
+
+		/*
+		 * We may have already read "secondary headers"; purge
+		 * them to give ourselves a clean restart.
+		 */
+		for (i = 0; header[i]; i++) {
+			if (s_hdr_data[i])
+				strbuf_release(s_hdr_data[i]);
+			s_hdr_data[i] = NULL;
+		}
+		return 0;
+	}
+
+	if (patchbreak(line)) {
+		fclose(cmitmsg);
+		cmitmsg = NULL;
+		return 1;
+	}
+
+	fputs(line->buf, cmitmsg);
+	return 0;
+}
+
+static void handle_patch(const struct strbuf *line)
+{
+	fwrite(line->buf, 1, line->len, patchfile);
+	patch_lines++;
+}
+
+static void handle_filter(struct strbuf *line)
+{
+	static int filter = 0;
+
+	/* filter tells us which part we left off on */
+	switch (filter) {
+	case 0:
+		if (!handle_commit_msg(line))
+			break;
+		filter++;
+	case 1:
+		handle_patch(line);
+		break;
+	}
+}
+
+static void handle_body(void)
+{
+	struct strbuf prev = STRBUF_INIT;
+
+	/* Skip up to the first boundary */
+	if (*content_top) {
+		if (!find_boundary())
+			goto handle_body_out;
+	}
+
+	do {
+		/* process any boundary lines */
+		if (*content_top && is_multipart_boundary(&line)) {
+			/* flush any leftover */
+			if (prev.len) {
+				handle_filter(&prev);
+				strbuf_reset(&prev);
+			}
+			if (!handle_boundary())
+				goto handle_body_out;
+		}
+
+		/* Unwrap transfer encoding */
+		decode_transfer_encoding(&line);
+
+		switch (transfer_encoding) {
+		case TE_BASE64:
+		case TE_QP:
+		{
+			struct strbuf **lines, **it, *sb;
+
+			/* Prepend any previous partial lines */
+			strbuf_insert(&line, 0, prev.buf, prev.len);
+			strbuf_reset(&prev);
+
+			/* binary data most likely doesn't have newlines */
+			if (message_type != TYPE_TEXT) {
+				handle_filter(&line);
+				break;
+			}
+			/*
+			 * This is a decoded line that may contain
+			 * multiple new lines.  Pass only one chunk
+			 * at a time to handle_filter()
+			 */
+			lines = strbuf_split(&line, '\n');
+			for (it = lines; (sb = *it); it++) {
+				if (*(it + 1) == NULL) /* The last line */
+					if (sb->buf[sb->len - 1] != '\n') {
+						/* Partial line, save it for later. */
+						strbuf_addbuf(&prev, sb);
+						break;
+					}
+				handle_filter(sb);
+			}
+			/*
+			 * The partial chunk is saved in "prev" and will be
+			 * appended by the next iteration of read_line_with_nul().
+			 */
+			strbuf_list_free(lines);
+			break;
+		}
+		default:
+			handle_filter(&line);
+		}
+
+	} while (!strbuf_getwholeline(&line, fin, '\n'));
+
+handle_body_out:
+	strbuf_release(&prev);
+}
+
+static void output_header_lines(FILE *fout, const char *hdr, const struct strbuf *data)
+{
+	const char *sp = data->buf;
+	while (1) {
+		char *ep = strchr(sp, '\n');
+		int len;
+		if (!ep)
+			len = strlen(sp);
+		else
+			len = ep - sp;
+		fprintf(fout, "%s: %.*s\n", hdr, len, sp);
+		if (!ep)
+			break;
+		sp = ep + 1;
+	}
+}
+
+static void handle_info(void)
+{
+	struct strbuf *hdr;
+	int i;
+
+	for (i = 0; header[i]; i++) {
+		/* only print inbody headers if we output a patch file */
+		if (patch_lines && s_hdr_data[i])
+			hdr = s_hdr_data[i];
+		else if (p_hdr_data[i])
+			hdr = p_hdr_data[i];
+		else
+			continue;
+
+		if (!memcmp(header[i], "Subject", 7)) {
+			if (!keep_subject) {
+				cleanup_subject(hdr);
+				cleanup_space(hdr);
+			}
+			output_header_lines(fout, "Subject", hdr);
+		} else if (!memcmp(header[i], "From", 4)) {
+			cleanup_space(hdr);
+			handle_from(hdr);
+			fprintf(fout, "Author: %s\n", name.buf);
+			fprintf(fout, "Email: %s\n", email.buf);
+		} else {
+			cleanup_space(hdr);
+			fprintf(fout, "%s: %s\n", header[i], hdr->buf);
+		}
+	}
+	fprintf(fout, "\n");
+}
+
+static int mailinfo(FILE *in, FILE *out, const char *msg, const char *patch)
+{
+	int peek;
+	fin = in;
+	fout = out;
+
+	cmitmsg = fopen(msg, "w");
+	if (!cmitmsg) {
+		perror(msg);
+		return -1;
+	}
+	patchfile = fopen(patch, "w");
+	if (!patchfile) {
+		perror(patch);
+		fclose(cmitmsg);
+		return -1;
+	}
+
+	p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*p_hdr_data));
+	s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*s_hdr_data));
+
+	do {
+		peek = fgetc(in);
+	} while (isspace(peek));
+	ungetc(peek, in);
+
+	/* process the email header */
+	while (read_one_header_line(&line, fin))
+		check_header(&line, p_hdr_data, 1);
+
+	handle_body();
+	handle_info();
+
+	return 0;
+}
+
+static int git_mailinfo_config(const char *var, const char *value, void *unused)
+{
+	if (prefixcmp(var, "mailinfo."))
+		return git_default_config(var, value, unused);
+	if (!strcmp(var, "mailinfo.scissors")) {
+		use_scissors = git_config_bool(var, value);
+		return 0;
+	}
+	/* perhaps others here */
+	return 0;
+}
+
+static const char mailinfo_usage[] =
+	"git mailinfo [-k|-b] [-u | --encoding=<encoding> | -n] [--scissors | --no-scissors] msg patch < mail >info";
+
+int cmd_mailinfo(int argc, const char **argv, const char *prefix)
+{
+	const char *def_charset;
+
+	/* NEEDSWORK: might want to do the optional .git/ directory
+	 * discovery
+	 */
+	git_config(git_mailinfo_config, NULL);
+
+	def_charset = (git_commit_encoding ? git_commit_encoding : "UTF-8");
+	metainfo_charset = def_charset;
+
+	while (1 < argc && argv[1][0] == '-') {
+		if (!strcmp(argv[1], "-k"))
+			keep_subject = 1;
+		else if (!strcmp(argv[1], "-b"))
+			keep_non_patch_brackets_in_subject = 1;
+		else if (!strcmp(argv[1], "-u"))
+			metainfo_charset = def_charset;
+		else if (!strcmp(argv[1], "-n"))
+			metainfo_charset = NULL;
+		else if (!prefixcmp(argv[1], "--encoding="))
+			metainfo_charset = argv[1] + 11;
+		else if (!strcmp(argv[1], "--scissors"))
+			use_scissors = 1;
+		else if (!strcmp(argv[1], "--no-scissors"))
+			use_scissors = 0;
+		else if (!strcmp(argv[1], "--no-inbody-headers"))
+			use_inbody_headers = 0;
+		else
+			usage(mailinfo_usage);
+		argc--; argv++;
+	}
+
+	if (argc != 3)
+		usage(mailinfo_usage);
+
+	return !!mailinfo(stdin, stdout, argv[1], argv[2]);
+}
diff --git a/builtin/mailsplit.c b/builtin/mailsplit.c
new file mode 100644
index 0000000..207e358
--- /dev/null
+++ b/builtin/mailsplit.c
@@ -0,0 +1,309 @@
+/*
+ * Totally braindamaged mbox splitter program.
+ *
+ * It just splits a mbox into a list of files: "0001" "0002" ..
+ * so you can process them further from there.
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "string-list.h"
+#include "strbuf.h"
+
+static const char git_mailsplit_usage[] =
+"git mailsplit [-d<prec>] [-f<n>] [-b] -o<directory> [<mbox>|<Maildir>...]";
+
+static int is_from_line(const char *line, int len)
+{
+	const char *colon;
+
+	if (len < 20 || memcmp("From ", line, 5))
+		return 0;
+
+	colon = line + len - 2;
+	line += 5;
+	for (;;) {
+		if (colon < line)
+			return 0;
+		if (*--colon == ':')
+			break;
+	}
+
+	if (!isdigit(colon[-4]) ||
+	    !isdigit(colon[-2]) ||
+	    !isdigit(colon[-1]) ||
+	    !isdigit(colon[ 1]) ||
+	    !isdigit(colon[ 2]))
+		return 0;
+
+	/* year */
+	if (strtol(colon+3, NULL, 10) <= 90)
+		return 0;
+
+	/* Ok, close enough */
+	return 1;
+}
+
+static struct strbuf buf = STRBUF_INIT;
+static int keep_cr;
+
+/* Called with the first line (potentially partial)
+ * already in buf[] -- normally that should begin with
+ * the Unix "From " line.  Write it into the specified
+ * file.
+ */
+static int split_one(FILE *mbox, const char *name, int allow_bare)
+{
+	FILE *output = NULL;
+	int fd;
+	int status = 0;
+	int is_bare = !is_from_line(buf.buf, buf.len);
+
+	if (is_bare && !allow_bare)
+		goto corrupt;
+
+	fd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0666);
+	if (fd < 0)
+		die_errno("cannot open output file '%s'", name);
+	output = xfdopen(fd, "w");
+
+	/* Copy it out, while searching for a line that begins with
+	 * "From " and having something that looks like a date format.
+	 */
+	for (;;) {
+		if (!keep_cr && buf.len > 1 && buf.buf[buf.len-1] == '\n' &&
+			buf.buf[buf.len-2] == '\r') {
+			strbuf_setlen(&buf, buf.len-2);
+			strbuf_addch(&buf, '\n');
+		}
+
+		if (fwrite(buf.buf, 1, buf.len, output) != buf.len)
+			die_errno("cannot write output");
+
+		if (strbuf_getwholeline(&buf, mbox, '\n')) {
+			if (feof(mbox)) {
+				status = 1;
+				break;
+			}
+			die_errno("cannot read mbox");
+		}
+		if (!is_bare && is_from_line(buf.buf, buf.len))
+			break; /* done with one message */
+	}
+	fclose(output);
+	return status;
+
+ corrupt:
+	if (output)
+		fclose(output);
+	unlink(name);
+	fprintf(stderr, "corrupt mailbox\n");
+	exit(1);
+}
+
+static int populate_maildir_list(struct string_list *list, const char *path)
+{
+	DIR *dir;
+	struct dirent *dent;
+	char name[PATH_MAX];
+	char *subs[] = { "cur", "new", NULL };
+	char **sub;
+
+	for (sub = subs; *sub; ++sub) {
+		snprintf(name, sizeof(name), "%s/%s", path, *sub);
+		if ((dir = opendir(name)) == NULL) {
+			if (errno == ENOENT)
+				continue;
+			error("cannot opendir %s (%s)", name, strerror(errno));
+			return -1;
+		}
+
+		while ((dent = readdir(dir)) != NULL) {
+			if (dent->d_name[0] == '.')
+				continue;
+			snprintf(name, sizeof(name), "%s/%s", *sub, dent->d_name);
+			string_list_insert(name, list);
+		}
+
+		closedir(dir);
+	}
+
+	return 0;
+}
+
+static int split_maildir(const char *maildir, const char *dir,
+	int nr_prec, int skip)
+{
+	char file[PATH_MAX];
+	char name[PATH_MAX];
+	int ret = -1;
+	int i;
+	struct string_list list = {NULL, 0, 0, 1};
+
+	if (populate_maildir_list(&list, maildir) < 0)
+		goto out;
+
+	for (i = 0; i < list.nr; i++) {
+		FILE *f;
+		snprintf(file, sizeof(file), "%s/%s", maildir, list.items[i].string);
+		f = fopen(file, "r");
+		if (!f) {
+			error("cannot open mail %s (%s)", file, strerror(errno));
+			goto out;
+		}
+
+		if (strbuf_getwholeline(&buf, f, '\n')) {
+			error("cannot read mail %s (%s)", file, strerror(errno));
+			goto out;
+		}
+
+		sprintf(name, "%s/%0*d", dir, nr_prec, ++skip);
+		split_one(f, name, 1);
+
+		fclose(f);
+	}
+
+	ret = skip;
+out:
+	string_list_clear(&list, 1);
+	return ret;
+}
+
+static int split_mbox(const char *file, const char *dir, int allow_bare,
+		      int nr_prec, int skip)
+{
+	char name[PATH_MAX];
+	int ret = -1;
+	int peek;
+
+	FILE *f = !strcmp(file, "-") ? stdin : fopen(file, "r");
+	int file_done = 0;
+
+	if (!f) {
+		error("cannot open mbox %s", file);
+		goto out;
+	}
+
+	do {
+		peek = fgetc(f);
+	} while (isspace(peek));
+	ungetc(peek, f);
+
+	if (strbuf_getwholeline(&buf, f, '\n')) {
+		/* empty stdin is OK */
+		if (f != stdin) {
+			error("cannot read mbox %s", file);
+			goto out;
+		}
+		file_done = 1;
+	}
+
+	while (!file_done) {
+		sprintf(name, "%s/%0*d", dir, nr_prec, ++skip);
+		file_done = split_one(f, name, allow_bare);
+	}
+
+	if (f != stdin)
+		fclose(f);
+
+	ret = skip;
+out:
+	return ret;
+}
+
+int cmd_mailsplit(int argc, const char **argv, const char *prefix)
+{
+	int nr = 0, nr_prec = 4, num = 0;
+	int allow_bare = 0;
+	const char *dir = NULL;
+	const char **argp;
+	static const char *stdin_only[] = { "-", NULL };
+
+	for (argp = argv+1; *argp; argp++) {
+		const char *arg = *argp;
+
+		if (arg[0] != '-')
+			break;
+		/* do flags here */
+		if ( arg[1] == 'd' ) {
+			nr_prec = strtol(arg+2, NULL, 10);
+			if (nr_prec < 3 || 10 <= nr_prec)
+				usage(git_mailsplit_usage);
+			continue;
+		} else if ( arg[1] == 'f' ) {
+			nr = strtol(arg+2, NULL, 10);
+		} else if ( arg[1] == 'h' ) {
+			usage(git_mailsplit_usage);
+		} else if ( arg[1] == 'b' && !arg[2] ) {
+			allow_bare = 1;
+		} else if (!strcmp(arg, "--keep-cr")) {
+			keep_cr = 1;
+		} else if ( arg[1] == 'o' && arg[2] ) {
+			dir = arg+2;
+		} else if ( arg[1] == '-' && !arg[2] ) {
+			argp++;	/* -- marks end of options */
+			break;
+		} else {
+			die("unknown option: %s", arg);
+		}
+	}
+
+	if ( !dir ) {
+		/* Backwards compatibility: if no -o specified, accept
+		   <mbox> <dir> or just <dir> */
+		switch (argc - (argp-argv)) {
+		case 1:
+			dir = argp[0];
+			argp = stdin_only;
+			break;
+		case 2:
+			stdin_only[0] = argp[0];
+			dir = argp[1];
+			argp = stdin_only;
+			break;
+		default:
+			usage(git_mailsplit_usage);
+		}
+	} else {
+		/* New usage: if no more argument, parse stdin */
+		if ( !*argp )
+			argp = stdin_only;
+	}
+
+	while (*argp) {
+		const char *arg = *argp++;
+		struct stat argstat;
+		int ret = 0;
+
+		if (arg[0] == '-' && arg[1] == 0) {
+			ret = split_mbox(arg, dir, allow_bare, nr_prec, nr);
+			if (ret < 0) {
+				error("cannot split patches from stdin");
+				return 1;
+			}
+			num += (ret - nr);
+			nr = ret;
+			continue;
+		}
+
+		if (stat(arg, &argstat) == -1) {
+			error("cannot stat %s (%s)", arg, strerror(errno));
+			return 1;
+		}
+
+		if (S_ISDIR(argstat.st_mode))
+			ret = split_maildir(arg, dir, nr_prec, nr);
+		else
+			ret = split_mbox(arg, dir, allow_bare, nr_prec, nr);
+
+		if (ret < 0) {
+			error("cannot split patches from %s", arg);
+			return 1;
+		}
+		num += (ret - nr);
+		nr = ret;
+	}
+
+	printf("%d\n", num);
+
+	return 0;
+}
diff --git a/builtin/merge-base.c b/builtin/merge-base.c
new file mode 100644
index 0000000..54e7ec2
--- /dev/null
+++ b/builtin/merge-base.c
@@ -0,0 +1,63 @@
+#include "builtin.h"
+#include "cache.h"
+#include "commit.h"
+#include "parse-options.h"
+
+static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
+{
+	struct commit_list *result;
+
+	result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0);
+
+	if (!result)
+		return 1;
+
+	while (result) {
+		printf("%s\n", sha1_to_hex(result->item->object.sha1));
+		if (!show_all)
+			return 0;
+		result = result->next;
+	}
+
+	return 0;
+}
+
+static const char * const merge_base_usage[] = {
+	"git merge-base [-a|--all] <commit> <commit>...",
+	NULL
+};
+
+static struct commit *get_commit_reference(const char *arg)
+{
+	unsigned char revkey[20];
+	struct commit *r;
+
+	if (get_sha1(arg, revkey))
+		die("Not a valid object name %s", arg);
+	r = lookup_commit_reference(revkey);
+	if (!r)
+		die("Not a valid commit name %s", arg);
+
+	return r;
+}
+
+int cmd_merge_base(int argc, const char **argv, const char *prefix)
+{
+	struct commit **rev;
+	int rev_nr = 0;
+	int show_all = 0;
+
+	struct option options[] = {
+		OPT_BOOLEAN('a', "all", &show_all, "outputs all common ancestors"),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0);
+	if (argc < 2)
+		usage_with_options(merge_base_usage, options);
+	rev = xmalloc(argc * sizeof(*rev));
+	while (argc-- > 0)
+		rev[rev_nr++] = get_commit_reference(*argv++);
+	return show_merge_base(rev, rev_nr, show_all);
+}
diff --git a/builtin/merge-file.c b/builtin/merge-file.c
new file mode 100644
index 0000000..1e70073
--- /dev/null
+++ b/builtin/merge-file.c
@@ -0,0 +1,96 @@
+#include "builtin.h"
+#include "cache.h"
+#include "xdiff/xdiff.h"
+#include "xdiff-interface.h"
+#include "parse-options.h"
+
+static const char *const merge_file_usage[] = {
+	"git merge-file [options] [-L name1 [-L orig [-L name2]]] file1 orig_file file2",
+	NULL
+};
+
+static int label_cb(const struct option *opt, const char *arg, int unset)
+{
+	static int label_count = 0;
+	const char **names = (const char **)opt->value;
+
+	if (label_count >= 3)
+		return error("too many labels on the command line");
+	names[label_count++] = arg;
+	return 0;
+}
+
+int cmd_merge_file(int argc, const char **argv, const char *prefix)
+{
+	const char *names[3] = { NULL, NULL, NULL };
+	mmfile_t mmfs[3];
+	mmbuffer_t result = {NULL, 0};
+	xmparam_t xmp = {{XDF_NEED_MINIMAL}};
+	int ret = 0, i = 0, to_stdout = 0;
+	int level = XDL_MERGE_ZEALOUS_ALNUM;
+	int style = 0, quiet = 0;
+	int favor = 0;
+	int nongit;
+
+	struct option options[] = {
+		OPT_BOOLEAN('p', "stdout", &to_stdout, "send results to standard output"),
+		OPT_SET_INT(0, "diff3", &style, "use a diff3 based merge", XDL_MERGE_DIFF3),
+		OPT_SET_INT(0, "ours", &favor, "for conflicts, use our version",
+			    XDL_MERGE_FAVOR_OURS),
+		OPT_SET_INT(0, "theirs", &favor, "for conflicts, use their version",
+			    XDL_MERGE_FAVOR_THEIRS),
+		OPT__QUIET(&quiet),
+		OPT_CALLBACK('L', NULL, names, "name",
+			     "set labels for file1/orig_file/file2", &label_cb),
+		OPT_END(),
+	};
+
+	prefix = setup_git_directory_gently(&nongit);
+	if (!nongit) {
+		/* Read the configuration file */
+		git_config(git_xmerge_config, NULL);
+		if (0 <= git_xmerge_style)
+			style = git_xmerge_style;
+	}
+
+	argc = parse_options(argc, argv, prefix, options, merge_file_usage, 0);
+	if (argc != 3)
+		usage_with_options(merge_file_usage, options);
+	if (quiet) {
+		if (!freopen("/dev/null", "w", stderr))
+			return error("failed to redirect stderr to /dev/null: "
+				     "%s\n", strerror(errno));
+	}
+
+	for (i = 0; i < 3; i++) {
+		if (!names[i])
+			names[i] = argv[i];
+		if (read_mmfile(mmfs + i, argv[i]))
+			return -1;
+		if (buffer_is_binary(mmfs[i].ptr, mmfs[i].size))
+			return error("Cannot merge binary files: %s\n",
+					argv[i]);
+	}
+
+	ret = xdl_merge(mmfs + 1, mmfs + 0, names[0], mmfs + 2, names[2],
+			&xmp, XDL_MERGE_FLAGS(level, style, favor), &result);
+
+	for (i = 0; i < 3; i++)
+		free(mmfs[i].ptr);
+
+	if (ret >= 0) {
+		const char *filename = argv[0];
+		FILE *f = to_stdout ? stdout : fopen(filename, "wb");
+
+		if (!f)
+			ret = error("Could not open %s for writing", filename);
+		else if (result.size &&
+			 fwrite(result.ptr, result.size, 1, f) != 1)
+			ret = error("Could not write to %s", filename);
+		else if (fclose(f))
+			ret = error("Could not close %s", filename);
+		free(result.ptr);
+	}
+
+	return ret;
+}
diff --git a/builtin/merge-index.c b/builtin/merge-index.c
new file mode 100644
index 0000000..2c4cf5e
--- /dev/null
+++ b/builtin/merge-index.c
@@ -0,0 +1,111 @@
+#include "cache.h"
+#include "run-command.h"
+#include "exec_cmd.h"
+
+static const char *pgm;
+static int one_shot, quiet;
+static int err;
+
+static int merge_entry(int pos, const char *path)
+{
+	int found;
+	const char *arguments[] = { pgm, "", "", "", path, "", "", "", NULL };
+	char hexbuf[4][60];
+	char ownbuf[4][60];
+
+	if (pos >= active_nr)
+		die("git merge-index: %s not in the cache", path);
+	found = 0;
+	do {
+		struct cache_entry *ce = active_cache[pos];
+		int stage = ce_stage(ce);
+
+		if (strcmp(ce->name, path))
+			break;
+		found++;
+		strcpy(hexbuf[stage], sha1_to_hex(ce->sha1));
+		sprintf(ownbuf[stage], "%o", ce->ce_mode);
+		arguments[stage] = hexbuf[stage];
+		arguments[stage + 4] = ownbuf[stage];
+	} while (++pos < active_nr);
+	if (!found)
+		die("git merge-index: %s not in the cache", path);
+
+	if (run_command_v_opt(arguments, 0)) {
+		if (one_shot)
+			err++;
+		else {
+			if (!quiet)
+				die("merge program failed");
+			exit(1);
+		}
+	}
+	return found;
+}
+
+static void merge_file(const char *path)
+{
+	int pos = cache_name_pos(path, strlen(path));
+
+	/*
+	 * If it already exists in the cache as stage0, it's
+	 * already merged and there is nothing to do.
+	 */
+	if (pos < 0)
+		merge_entry(-pos-1, path);
+}
+
+static void merge_all(void)
+{
+	int i;
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (!ce_stage(ce))
+			continue;
+		i += merge_entry(i, ce->name)-1;
+	}
+}
+
+int cmd_merge_index(int argc, const char **argv, const char *prefix)
+{
+	int i, force_file = 0;
+
+	/* Without this we cannot rely on waitpid() to tell
+	 * what happened to our children.
+	 */
+	signal(SIGCHLD, SIG_DFL);
+
+	if (argc < 3)
+		usage("git merge-index [-o] [-q] <merge-program> (-a | [--] <filename>*)");
+
+	read_cache();
+
+	i = 1;
+	if (!strcmp(argv[i], "-o")) {
+		one_shot = 1;
+		i++;
+	}
+	if (!strcmp(argv[i], "-q")) {
+		quiet = 1;
+		i++;
+	}
+	pgm = argv[i++];
+	for (; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!force_file && *arg == '-') {
+			if (!strcmp(arg, "--")) {
+				force_file = 1;
+				continue;
+			}
+			if (!strcmp(arg, "-a")) {
+				merge_all();
+				continue;
+			}
+			die("git merge-index: unknown option %s", arg);
+		}
+		merge_file(arg);
+	}
+	if (err && !quiet)
+		die("merge program failed");
+	return err;
+}
diff --git a/builtin/merge-ours.c b/builtin/merge-ours.c
new file mode 100644
index 0000000..6844116
--- /dev/null
+++ b/builtin/merge-ours.c
@@ -0,0 +1,34 @@
+/*
+ * Implementation of git-merge-ours.sh as builtin
+ *
+ * Copyright (c) 2007 Thomas Harning Jr
+ * Original:
+ * Original Copyright (c) 2005 Junio C Hamano
+ *
+ * Pretend we resolved the heads, but declare our tree trumps everybody else.
+ */
+#include "git-compat-util.h"
+#include "builtin.h"
+
+static const char builtin_merge_ours_usage[] =
+	"git merge-ours <base>... -- HEAD <remote>...";
+
+static const char *diff_index_args[] = {
+	"diff-index", "--quiet", "--cached", "HEAD", "--", NULL
+};
+#define NARGS (ARRAY_SIZE(diff_index_args) - 1)
+
+int cmd_merge_ours(int argc, const char **argv, const char *prefix)
+{
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage(builtin_merge_ours_usage);
+
+	/*
+	 * We need to exit with 2 if the index does not match our HEAD tree,
+	 * because the current index is what we will be committing as the
+	 * merge result.
+	 */
+	if (cmd_diff_index(NARGS, diff_index_args, prefix))
+		exit(2);
+	exit(0);
+}
diff --git a/builtin/merge-recursive.c b/builtin/merge-recursive.c
new file mode 100644
index 0000000..d8875d5
--- /dev/null
+++ b/builtin/merge-recursive.c
@@ -0,0 +1,84 @@
+#include "cache.h"
+#include "commit.h"
+#include "tag.h"
+#include "merge-recursive.h"
+
+static const char *better_branch_name(const char *branch)
+{
+	static char githead_env[8 + 40 + 1];
+	char *name;
+
+	if (strlen(branch) != 40)
+		return branch;
+	sprintf(githead_env, "GITHEAD_%s", branch);
+	name = getenv(githead_env);
+	return name ? name : branch;
+}
+
+int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
+{
+	const unsigned char *bases[21];
+	unsigned bases_count = 0;
+	int i, failed;
+	unsigned char h1[20], h2[20];
+	struct merge_options o;
+	struct commit *result;
+
+	init_merge_options(&o);
+	if (argv[0] && !suffixcmp(argv[0], "-subtree"))
+		o.subtree_shift = "";
+
+	if (argc < 4)
+		usagef("%s <base>... -- <head> <remote> ...", argv[0]);
+
+	for (i = 1; i < argc; ++i) {
+		const char *arg = argv[i];
+
+		if (!prefixcmp(arg, "--")) {
+			if (!arg[2])
+				break;
+			if (!strcmp(arg+2, "ours"))
+				o.recursive_variant = MERGE_RECURSIVE_OURS;
+			else if (!strcmp(arg+2, "theirs"))
+				o.recursive_variant = MERGE_RECURSIVE_THEIRS;
+			else if (!strcmp(arg+2, "subtree"))
+				o.subtree_shift = "";
+			else if (!prefixcmp(arg+2, "subtree="))
+				o.subtree_shift = arg + 10;
+			else
+				die("Unknown option %s", arg);
+			continue;
+		}
+		if (bases_count < ARRAY_SIZE(bases)-1) {
+			unsigned char *sha = xmalloc(20);
+			if (get_sha1(argv[i], sha))
+				die("Could not parse object '%s'", argv[i]);
+			bases[bases_count++] = sha;
+		}
+		else
+			warning("Cannot handle more than %d bases. "
+				"Ignoring %s.",
+				(int)ARRAY_SIZE(bases)-1, argv[i]);
+	}
+	if (argc - i != 3) /* "--" "<head>" "<remote>" */
+		die("Not handling anything other than two heads merge.");
+
+	o.branch1 = argv[++i];
+	o.branch2 = argv[++i];
+
+	if (get_sha1(o.branch1, h1))
+		die("Could not resolve ref '%s'", o.branch1);
+	if (get_sha1(o.branch2, h2))
+		die("Could not resolve ref '%s'", o.branch2);
+
+	o.branch1 = better_branch_name(o.branch1);
+	o.branch2 = better_branch_name(o.branch2);
+
+	if (o.verbosity >= 3)
+		printf("Merging %s with %s\n", o.branch1, o.branch2);
+
+	failed = merge_recursive_generic(&o, h1, h2, bases_count, bases, &result);
+	if (failed < 0)
+		return 128; /* die() error code */
+	return failed;
+}
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
new file mode 100644
index 0000000..a4a4f2c
--- /dev/null
+++ b/builtin/merge-tree.c
@@ -0,0 +1,358 @@
+#include "cache.h"
+#include "tree-walk.h"
+#include "xdiff-interface.h"
+#include "blob.h"
+#include "exec_cmd.h"
+
+static const char merge_tree_usage[] = "git merge-tree <base-tree> <branch1> <branch2>";
+static int resolve_directories = 1;
+
+struct merge_list {
+	struct merge_list *next;
+	struct merge_list *link;	/* other stages for this object */
+
+	unsigned int stage : 2,
+		     flags : 30;
+	unsigned int mode;
+	const char *path;
+	struct blob *blob;
+};
+
+static struct merge_list *merge_result, **merge_result_end = &merge_result;
+
+static void add_merge_entry(struct merge_list *entry)
+{
+	*merge_result_end = entry;
+	merge_result_end = &entry->next;
+}
+
+static void merge_trees(struct tree_desc t[3], const char *base);
+
+static const char *explanation(struct merge_list *entry)
+{
+	switch (entry->stage) {
+	case 0:
+		return "merged";
+	case 3:
+		return "added in remote";
+	case 2:
+		if (entry->link)
+			return "added in both";
+		return "added in local";
+	}
+
+	/* Existed in base */
+	entry = entry->link;
+	if (!entry)
+		return "removed in both";
+
+	if (entry->link)
+		return "changed in both";
+
+	if (entry->stage == 3)
+		return "removed in local";
+	return "removed in remote";
+}
+
+extern void *merge_file(const char *, struct blob *, struct blob *, struct blob *, unsigned long *);
+
+static void *result(struct merge_list *entry, unsigned long *size)
+{
+	enum object_type type;
+	struct blob *base, *our, *their;
+
+	if (!entry->stage)
+		return read_sha1_file(entry->blob->object.sha1, &type, size);
+	base = NULL;
+	if (entry->stage == 1) {
+		base = entry->blob;
+		entry = entry->link;
+	}
+	our = NULL;
+	if (entry && entry->stage == 2) {
+		our = entry->blob;
+		entry = entry->link;
+	}
+	their = NULL;
+	if (entry)
+		their = entry->blob;
+	return merge_file(entry->path, base, our, their, size);
+}
+
+static void *origin(struct merge_list *entry, unsigned long *size)
+{
+	enum object_type type;
+	while (entry) {
+		if (entry->stage == 2)
+			return read_sha1_file(entry->blob->object.sha1, &type, size);
+		entry = entry->link;
+	}
+	return NULL;
+}
+
+static int show_outf(void *priv_, mmbuffer_t *mb, int nbuf)
+{
+	int i;
+	for (i = 0; i < nbuf; i++)
+		printf("%.*s", (int) mb[i].size, mb[i].ptr);
+	return 0;
+}
+
+static void show_diff(struct merge_list *entry)
+{
+	unsigned long size;
+	mmfile_t src, dst;
+	xpparam_t xpp;
+	xdemitconf_t xecfg;
+	xdemitcb_t ecb;
+
+	xpp.flags = XDF_NEED_MINIMAL;
+	memset(&xecfg, 0, sizeof(xecfg));
+	xecfg.ctxlen = 3;
+	ecb.outf = show_outf;
+	ecb.priv = NULL;
+
+	src.ptr = origin(entry, &size);
+	if (!src.ptr)
+		size = 0;
+	src.size = size;
+	dst.ptr = result(entry, &size);
+	if (!dst.ptr)
+		size = 0;
+	dst.size = size;
+	xdi_diff(&src, &dst, &xpp, &xecfg, &ecb);
+	free(src.ptr);
+	free(dst.ptr);
+}
+
+static void show_result_list(struct merge_list *entry)
+{
+	printf("%s\n", explanation(entry));
+	do {
+		struct merge_list *link = entry->link;
+		static const char *desc[4] = { "result", "base", "our", "their" };
+		printf("  %-6s %o %s %s\n", desc[entry->stage], entry->mode, sha1_to_hex(entry->blob->object.sha1), entry->path);
+		entry = link;
+	} while (entry);
+}
+
+static void show_result(void)
+{
+	struct merge_list *walk;
+
+	walk = merge_result;
+	while (walk) {
+		show_result_list(walk);
+		show_diff(walk);
+		walk = walk->next;
+	}
+}
+
+/* An empty entry never compares same, not even to another empty entry */
+static int same_entry(struct name_entry *a, struct name_entry *b)
+{
+	return	a->sha1 &&
+		b->sha1 &&
+		!hashcmp(a->sha1, b->sha1) &&
+		a->mode == b->mode;
+}
+
+static struct merge_list *create_entry(unsigned stage, unsigned mode, const unsigned char *sha1, const char *path)
+{
+	struct merge_list *res = xcalloc(1, sizeof(*res));
+
+	res->stage = stage;
+	res->path = path;
+	res->mode = mode;
+	res->blob = lookup_blob(sha1);
+	return res;
+}
+
+static char *traverse_path(const struct traverse_info *info, const struct name_entry *n)
+{
+	char *path = xmalloc(traverse_path_len(info, n) + 1);
+	return make_traverse_path(path, info, n);
+}
+
+static void resolve(const struct traverse_info *info, struct name_entry *branch1, struct name_entry *result)
+{
+	struct merge_list *orig, *final;
+	const char *path;
+
+	/* If it's already branch1, don't bother showing it */
+	if (!branch1)
+		return;
+
+	path = traverse_path(info, result);
+	orig = create_entry(2, branch1->mode, branch1->sha1, path);
+	final = create_entry(0, result->mode, result->sha1, path);
+
+	final->link = orig;
+
+	add_merge_entry(final);
+}
+
+static int unresolved_directory(const struct traverse_info *info, struct name_entry n[3])
+{
+	char *newbase;
+	struct name_entry *p;
+	struct tree_desc t[3];
+	void *buf0, *buf1, *buf2;
+
+	if (!resolve_directories)
+		return 0;
+	p = n;
+	if (!p->mode) {
+		p++;
+		if (!p->mode)
+			p++;
+	}
+	if (!S_ISDIR(p->mode))
+		return 0;
+	newbase = traverse_path(info, p);
+	buf0 = fill_tree_descriptor(t+0, n[0].sha1);
+	buf1 = fill_tree_descriptor(t+1, n[1].sha1);
+	buf2 = fill_tree_descriptor(t+2, n[2].sha1);
+	merge_trees(t, newbase);
+
+	free(buf0);
+	free(buf1);
+	free(buf2);
+	free(newbase);
+	return 1;
+}
+
+
+static struct merge_list *link_entry(unsigned stage, const struct traverse_info *info, struct name_entry *n, struct merge_list *entry)
+{
+	const char *path;
+	struct merge_list *link;
+
+	if (!n->mode)
+		return entry;
+	if (entry)
+		path = entry->path;
+	else
+		path = traverse_path(info, n);
+	link = create_entry(stage, n->mode, n->sha1, path);
+	link->link = entry;
+	return link;
+}
+
+static void unresolved(const struct traverse_info *info, struct name_entry n[3])
+{
+	struct merge_list *entry = NULL;
+
+	if (unresolved_directory(info, n))
+		return;
+
+	/*
+	 * Do them in reverse order so that the resulting link
+	 * list has the stages in order - link_entry adds new
+	 * links at the front.
+	 */
+	entry = link_entry(3, info, n + 2, entry);
+	entry = link_entry(2, info, n + 1, entry);
+	entry = link_entry(1, info, n + 0, entry);
+
+	add_merge_entry(entry);
+}
+
+/*
+ * Merge two trees together (t[1] and t[2]), using a common base (t[0])
+ * as the origin.
+ *
+ * This walks the (sorted) trees in lock-step, checking every possible
+ * name. Note that directories automatically sort differently from other
+ * files (see "base_name_compare"), so you'll never see file/directory
+ * conflicts, because they won't ever compare the same.
+ *
+ * IOW, if a directory changes to a filename, it will automatically be
+ * seen as the directory going away, and the filename being created.
+ *
+ * Think of this as a three-way diff.
+ *
+ * The output will be either:
+ *  - successful merge
+ *	 "0 mode sha1 filename"
+ *    NOTE NOTE NOTE! FIXME! We really really need to walk the index
+ *    in parallel with this too!
+ *
+ *  - conflict:
+ *	"1 mode sha1 filename"
+ *	"2 mode sha1 filename"
+ *	"3 mode sha1 filename"
+ *    where not all of the 1/2/3 lines may exist, of course.
+ *
+ * The successful merge rules are the same as for the three-way merge
+ * in git-read-tree.
+ */
+static int threeway_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *info)
+{
+	/* Same in both? */
+	if (same_entry(entry+1, entry+2)) {
+		if (entry[0].sha1) {
+			resolve(info, NULL, entry+1);
+			return mask;
+		}
+	}
+
+	if (same_entry(entry+0, entry+1)) {
+		if (entry[2].sha1 && !S_ISDIR(entry[2].mode)) {
+			resolve(info, entry+1, entry+2);
+			return mask;
+		}
+	}
+
+	if (same_entry(entry+0, entry+2)) {
+		if (entry[1].sha1 && !S_ISDIR(entry[1].mode)) {
+			resolve(info, NULL, entry+1);
+			return mask;
+		}
+	}
+
+	unresolved(info, entry);
+	return mask;
+}
+
+static void merge_trees(struct tree_desc t[3], const char *base)
+{
+	struct traverse_info info;
+
+	setup_traverse_info(&info, base);
+	info.fn = threeway_callback;
+	traverse_trees(3, t, &info);
+}
+
+static void *get_tree_descriptor(struct tree_desc *desc, const char *rev)
+{
+	unsigned char sha1[20];
+	void *buf;
+
+	if (get_sha1(rev, sha1))
+		die("unknown rev %s", rev);
+	buf = fill_tree_descriptor(desc, sha1);
+	if (!buf)
+		die("%s is not a tree", rev);
+	return buf;
+}
+
+int cmd_merge_tree(int argc, const char **argv, const char *prefix)
+{
+	struct tree_desc t[3];
+	void *buf1, *buf2, *buf3;
+
+	if (argc != 4)
+		usage(merge_tree_usage);
+
+	buf1 = get_tree_descriptor(t+0, argv[1]);
+	buf2 = get_tree_descriptor(t+1, argv[2]);
+	buf3 = get_tree_descriptor(t+2, argv[3]);
+	merge_trees(t, "");
+	free(buf1);
+	free(buf2);
+	free(buf3);
+
+	show_result();
+	return 0;
+}
diff --git a/builtin/merge.c b/builtin/merge.c
new file mode 100644
index 0000000..3aaec7b
--- /dev/null
+++ b/builtin/merge.c
@@ -0,0 +1,1292 @@
+/*
+ * Builtin "git merge"
+ *
+ * Copyright (c) 2008 Miklos Vajna <vmiklos@frugalware.org>
+ *
+ * Based on git-merge.sh by Junio C Hamano.
+ */
+
+#include "cache.h"
+#include "parse-options.h"
+#include "builtin.h"
+#include "run-command.h"
+#include "diff.h"
+#include "refs.h"
+#include "commit.h"
+#include "diffcore.h"
+#include "revision.h"
+#include "unpack-trees.h"
+#include "cache-tree.h"
+#include "dir.h"
+#include "utf8.h"
+#include "log-tree.h"
+#include "color.h"
+#include "rerere.h"
+#include "help.h"
+#include "merge-recursive.h"
+#include "resolve-undo.h"
+
+#define DEFAULT_TWOHEAD (1<<0)
+#define DEFAULT_OCTOPUS (1<<1)
+#define NO_FAST_FORWARD (1<<2)
+#define NO_TRIVIAL      (1<<3)
+
+struct strategy {
+	const char *name;
+	unsigned attr;
+};
+
+static const char * const builtin_merge_usage[] = {
+	"git merge [options] <remote>...",
+	"git merge [options] <msg> HEAD <remote>",
+	NULL
+};
+
+static int show_diffstat = 1, option_log, squash;
+static int option_commit = 1, allow_fast_forward = 1;
+static int fast_forward_only;
+static int allow_trivial = 1, have_message;
+static struct strbuf merge_msg;
+static struct commit_list *remoteheads;
+static unsigned char head[20], stash[20];
+static struct strategy **use_strategies;
+static size_t use_strategies_nr, use_strategies_alloc;
+static const char **xopts;
+static size_t xopts_nr, xopts_alloc;
+static const char *branch;
+static int verbosity;
+static int allow_rerere_auto;
+
+static struct strategy all_strategy[] = {
+	{ "recursive",  DEFAULT_TWOHEAD | NO_TRIVIAL },
+	{ "octopus",    DEFAULT_OCTOPUS },
+	{ "resolve",    0 },
+	{ "ours",       NO_FAST_FORWARD | NO_TRIVIAL },
+	{ "subtree",    NO_FAST_FORWARD | NO_TRIVIAL },
+};
+
+static const char *pull_twohead, *pull_octopus;
+
+static int option_parse_message(const struct option *opt,
+				const char *arg, int unset)
+{
+	struct strbuf *buf = opt->value;
+
+	if (unset)
+		strbuf_setlen(buf, 0);
+	else if (arg) {
+		strbuf_addf(buf, "%s%s", buf->len ? "\n\n" : "", arg);
+		have_message = 1;
+	} else
+		return error("switch `m' requires a value");
+	return 0;
+}
+
+static struct strategy *get_strategy(const char *name)
+{
+	int i;
+	struct strategy *ret;
+	static struct cmdnames main_cmds, other_cmds;
+	static int loaded;
+
+	if (!name)
+		return NULL;
+
+	for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
+		if (!strcmp(name, all_strategy[i].name))
+			return &all_strategy[i];
+
+	if (!loaded) {
+		struct cmdnames not_strategies;
+		loaded = 1;
+
+		memset(&not_strategies, 0, sizeof(struct cmdnames));
+		load_command_list("git-merge-", &main_cmds, &other_cmds);
+		for (i = 0; i < main_cmds.cnt; i++) {
+			int j, found = 0;
+			struct cmdname *ent = main_cmds.names[i];
+			for (j = 0; j < ARRAY_SIZE(all_strategy); j++)
+				if (!strncmp(ent->name, all_strategy[j].name, ent->len)
+						&& !all_strategy[j].name[ent->len])
+					found = 1;
+			if (!found)
+				add_cmdname(&not_strategies, ent->name, ent->len);
+		}
+		exclude_cmds(&main_cmds, &not_strategies);
+	}
+	if (!is_in_cmdlist(&main_cmds, name) && !is_in_cmdlist(&other_cmds, name)) {
+		fprintf(stderr, "Could not find merge strategy '%s'.\n", name);
+		fprintf(stderr, "Available strategies are:");
+		for (i = 0; i < main_cmds.cnt; i++)
+			fprintf(stderr, " %s", main_cmds.names[i]->name);
+		fprintf(stderr, ".\n");
+		if (other_cmds.cnt) {
+			fprintf(stderr, "Available custom strategies are:");
+			for (i = 0; i < other_cmds.cnt; i++)
+				fprintf(stderr, " %s", other_cmds.names[i]->name);
+			fprintf(stderr, ".\n");
+		}
+		exit(1);
+	}
+
+	ret = xcalloc(1, sizeof(struct strategy));
+	ret->name = xstrdup(name);
+	return ret;
+}
+
+static void append_strategy(struct strategy *s)
+{
+	ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
+	use_strategies[use_strategies_nr++] = s;
+}
+
+static int option_parse_strategy(const struct option *opt,
+				 const char *name, int unset)
+{
+	if (unset)
+		return 0;
+
+	append_strategy(get_strategy(name));
+	return 0;
+}
+
+static int option_parse_x(const struct option *opt,
+			  const char *arg, int unset)
+{
+	if (unset)
+		return 0;
+
+	ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
+	xopts[xopts_nr++] = xstrdup(arg);
+	return 0;
+}
+
+static int option_parse_n(const struct option *opt,
+			  const char *arg, int unset)
+{
+	show_diffstat = unset;
+	return 0;
+}
+
+static struct option builtin_merge_options[] = {
+	{ OPTION_CALLBACK, 'n', NULL, NULL, NULL,
+		"do not show a diffstat at the end of the merge",
+		PARSE_OPT_NOARG, option_parse_n },
+	OPT_BOOLEAN(0, "stat", &show_diffstat,
+		"show a diffstat at the end of the merge"),
+	OPT_BOOLEAN(0, "summary", &show_diffstat, "(synonym to --stat)"),
+	OPT_BOOLEAN(0, "log", &option_log,
+		"add list of one-line log to merge commit message"),
+	OPT_BOOLEAN(0, "squash", &squash,
+		"create a single commit instead of doing a merge"),
+	OPT_BOOLEAN(0, "commit", &option_commit,
+		"perform a commit if the merge succeeds (default)"),
+	OPT_BOOLEAN(0, "ff", &allow_fast_forward,
+		"allow fast-forward (default)"),
+	OPT_BOOLEAN(0, "ff-only", &fast_forward_only,
+		"abort if fast-forward is not possible"),
+	OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
+	OPT_CALLBACK('s', "strategy", &use_strategies, "strategy",
+		"merge strategy to use", option_parse_strategy),
+	OPT_CALLBACK('X', "strategy-option", &xopts, "option=value",
+		"option for selected merge strategy", option_parse_x),
+	OPT_CALLBACK('m', "message", &merge_msg, "message",
+		"message to be used for the merge commit (if any)",
+		option_parse_message),
+	OPT__VERBOSITY(&verbosity),
+	OPT_END()
+};
+
+/* Cleans up metadata that is uninteresting after a succeeded merge. */
+static void drop_save(void)
+{
+	unlink(git_path("MERGE_HEAD"));
+	unlink(git_path("MERGE_MSG"));
+	unlink(git_path("MERGE_MODE"));
+}
+
+static void save_state(void)
+{
+	int len;
+	struct child_process cp;
+	struct strbuf buffer = STRBUF_INIT;
+	const char *argv[] = {"stash", "create", NULL};
+
+	memset(&cp, 0, sizeof(cp));
+	cp.argv = argv;
+	cp.out = -1;
+	cp.git_cmd = 1;
+
+	if (start_command(&cp))
+		die("could not run stash.");
+	len = strbuf_read(&buffer, cp.out, 1024);
+	close(cp.out);
+
+	if (finish_command(&cp) || len < 0)
+		die("stash failed");
+	else if (!len)
+		return;
+	strbuf_setlen(&buffer, buffer.len-1);
+	if (get_sha1(buffer.buf, stash))
+		die("not a valid object: %s", buffer.buf);
+}
+
+static void reset_hard(unsigned const char *sha1, int verbose)
+{
+	int i = 0;
+	const char *args[6];
+
+	args[i++] = "read-tree";
+	if (verbose)
+		args[i++] = "-v";
+	args[i++] = "--reset";
+	args[i++] = "-u";
+	args[i++] = sha1_to_hex(sha1);
+	args[i] = NULL;
+
+	if (run_command_v_opt(args, RUN_GIT_CMD))
+		die("read-tree failed");
+}
+
+static void restore_state(void)
+{
+	struct strbuf sb = STRBUF_INIT;
+	const char *args[] = { "stash", "apply", NULL, NULL };
+
+	if (is_null_sha1(stash))
+		return;
+
+	reset_hard(head, 1);
+
+	args[2] = sha1_to_hex(stash);
+
+	/*
+	 * It is OK to ignore error here, for example when there was
+	 * nothing to restore.
+	 */
+	run_command_v_opt(args, RUN_GIT_CMD);
+
+	strbuf_release(&sb);
+	refresh_cache(REFRESH_QUIET);
+}
+
+/* This is called when no merge was necessary. */
+static void finish_up_to_date(const char *msg)
+{
+	if (verbosity >= 0)
+		printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
+	drop_save();
+}
+
+static void squash_message(void)
+{
+	struct rev_info rev;
+	struct commit *commit;
+	struct strbuf out = STRBUF_INIT;
+	struct commit_list *j;
+	int fd;
+	struct pretty_print_context ctx = {0};
+
+	printf("Squash commit -- not updating HEAD\n");
+	fd = open(git_path("SQUASH_MSG"), O_WRONLY | O_CREAT, 0666);
+	if (fd < 0)
+		die_errno("Could not write to '%s'", git_path("SQUASH_MSG"));
+
+	init_revisions(&rev, NULL);
+	rev.ignore_merges = 1;
+	rev.commit_format = CMIT_FMT_MEDIUM;
+
+	commit = lookup_commit(head);
+	commit->object.flags |= UNINTERESTING;
+	add_pending_object(&rev, &commit->object, NULL);
+
+	for (j = remoteheads; j; j = j->next)
+		add_pending_object(&rev, &j->item->object, NULL);
+
+	setup_revisions(0, NULL, &rev, NULL);
+	if (prepare_revision_walk(&rev))
+		die("revision walk setup failed");
+
+	ctx.abbrev = rev.abbrev;
+	ctx.date_mode = rev.date_mode;
+
+	strbuf_addstr(&out, "Squashed commit of the following:\n");
+	while ((commit = get_revision(&rev)) != NULL) {
+		strbuf_addch(&out, '\n');
+		strbuf_addf(&out, "commit %s\n",
+			sha1_to_hex(commit->object.sha1));
+		pretty_print_commit(rev.commit_format, commit, &out, &ctx);
+	}
+	if (write(fd, out.buf, out.len) < 0)
+		die_errno("Writing SQUASH_MSG");
+	if (close(fd))
+		die_errno("Finishing SQUASH_MSG");
+	strbuf_release(&out);
+}
+
+static void finish(const unsigned char *new_head, const char *msg)
+{
+	struct strbuf reflog_message = STRBUF_INIT;
+
+	if (!msg)
+		strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
+	else {
+		if (verbosity >= 0)
+			printf("%s\n", msg);
+		strbuf_addf(&reflog_message, "%s: %s",
+			getenv("GIT_REFLOG_ACTION"), msg);
+	}
+	if (squash) {
+		squash_message();
+	} else {
+		if (verbosity >= 0 && !merge_msg.len)
+			printf("No merge message -- not updating HEAD\n");
+		else {
+			const char *argv_gc_auto[] = { "gc", "--auto", NULL };
+			update_ref(reflog_message.buf, "HEAD",
+				new_head, head, 0,
+				DIE_ON_ERR);
+			/*
+			 * We ignore errors in 'gc --auto', since the
+			 * user should see them.
+			 */
+			run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
+		}
+	}
+	if (new_head && show_diffstat) {
+		struct diff_options opts;
+		diff_setup(&opts);
+		opts.output_format |=
+			DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
+		opts.detect_rename = DIFF_DETECT_RENAME;
+		if (diff_use_color_default > 0)
+			DIFF_OPT_SET(&opts, COLOR_DIFF);
+		if (diff_setup_done(&opts) < 0)
+			die("diff_setup_done failed");
+		diff_tree_sha1(head, new_head, "", &opts);
+		diffcore_std(&opts);
+		diff_flush(&opts);
+	}
+
+	/* Run a post-merge hook */
+	run_hook(NULL, "post-merge", squash ? "1" : "0", NULL);
+
+	strbuf_release(&reflog_message);
+}
+
+/* Get the name for the merge commit's message. */
+static void merge_name(const char *remote, struct strbuf *msg)
+{
+	struct object *remote_head;
+	unsigned char branch_head[20], buf_sha[20];
+	struct strbuf buf = STRBUF_INIT;
+	struct strbuf bname = STRBUF_INIT;
+	const char *ptr;
+	char *found_ref;
+	int len, early;
+
+	strbuf_branchname(&bname, remote);
+	remote = bname.buf;
+
+	memset(branch_head, 0, sizeof(branch_head));
+	remote_head = peel_to_type(remote, 0, NULL, OBJ_COMMIT);
+	if (!remote_head)
+		die("'%s' does not point to a commit", remote);
+
+	if (dwim_ref(remote, strlen(remote), branch_head, &found_ref) > 0) {
+		if (!prefixcmp(found_ref, "refs/heads/")) {
+			strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
+				    sha1_to_hex(branch_head), remote);
+			goto cleanup;
+		}
+		if (!prefixcmp(found_ref, "refs/remotes/")) {
+			strbuf_addf(msg, "%s\t\tremote branch '%s' of .\n",
+				    sha1_to_hex(branch_head), remote);
+			goto cleanup;
+		}
+	}
+
+	/* See if remote matches <name>^^^.. or <name>~<number> */
+	for (len = 0, ptr = remote + strlen(remote);
+	     remote < ptr && ptr[-1] == '^';
+	     ptr--)
+		len++;
+	if (len)
+		early = 1;
+	else {
+		early = 0;
+		ptr = strrchr(remote, '~');
+		if (ptr) {
+			int seen_nonzero = 0;
+
+			len++; /* count ~ */
+			while (*++ptr && isdigit(*ptr)) {
+				seen_nonzero |= (*ptr != '0');
+				len++;
+			}
+			if (*ptr)
+				len = 0; /* not ...~<number> */
+			else if (seen_nonzero)
+				early = 1;
+			else if (len == 1)
+				early = 1; /* "name~" is "name~1"! */
+		}
+	}
+	if (len) {
+		struct strbuf truname = STRBUF_INIT;
+		strbuf_addstr(&truname, "refs/heads/");
+		strbuf_addstr(&truname, remote);
+		strbuf_setlen(&truname, truname.len - len);
+		if (resolve_ref(truname.buf, buf_sha, 0, NULL)) {
+			strbuf_addf(msg,
+				    "%s\t\tbranch '%s'%s of .\n",
+				    sha1_to_hex(remote_head->sha1),
+				    truname.buf + 11,
+				    (early ? " (early part)" : ""));
+			strbuf_release(&truname);
+			goto cleanup;
+		}
+	}
+
+	if (!strcmp(remote, "FETCH_HEAD") &&
+			!access(git_path("FETCH_HEAD"), R_OK)) {
+		FILE *fp;
+		struct strbuf line = STRBUF_INIT;
+		char *ptr;
+
+		fp = fopen(git_path("FETCH_HEAD"), "r");
+		if (!fp)
+			die_errno("could not open '%s' for reading",
+				  git_path("FETCH_HEAD"));
+		strbuf_getline(&line, fp, '\n');
+		fclose(fp);
+		ptr = strstr(line.buf, "\tnot-for-merge\t");
+		if (ptr)
+			strbuf_remove(&line, ptr-line.buf+1, 13);
+		strbuf_addbuf(msg, &line);
+		strbuf_release(&line);
+		goto cleanup;
+	}
+	strbuf_addf(msg, "%s\t\tcommit '%s'\n",
+		sha1_to_hex(remote_head->sha1), remote);
+cleanup:
+	strbuf_release(&buf);
+	strbuf_release(&bname);
+}
+
+static int git_merge_config(const char *k, const char *v, void *cb)
+{
+	if (branch && !prefixcmp(k, "branch.") &&
+		!prefixcmp(k + 7, branch) &&
+		!strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
+		const char **argv;
+		int argc;
+		char *buf;
+
+		buf = xstrdup(v);
+		argc = split_cmdline(buf, &argv);
+		if (argc < 0)
+			die("Bad branch.%s.mergeoptions string", branch);
+		argv = xrealloc(argv, sizeof(*argv) * (argc + 2));
+		memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
+		argc++;
+		parse_options(argc, argv, NULL, builtin_merge_options,
+			      builtin_merge_usage, 0);
+		free(buf);
+	}
+
+	if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
+		show_diffstat = git_config_bool(k, v);
+	else if (!strcmp(k, "pull.twohead"))
+		return git_config_string(&pull_twohead, k, v);
+	else if (!strcmp(k, "pull.octopus"))
+		return git_config_string(&pull_octopus, k, v);
+	else if (!strcmp(k, "merge.log") || !strcmp(k, "merge.summary"))
+		option_log = git_config_bool(k, v);
+	return git_diff_ui_config(k, v, cb);
+}
+
+static int read_tree_trivial(unsigned char *common, unsigned char *head,
+			     unsigned char *one)
+{
+	int i, nr_trees = 0;
+	struct tree *trees[MAX_UNPACK_TREES];
+	struct tree_desc t[MAX_UNPACK_TREES];
+	struct unpack_trees_options opts;
+
+	memset(&opts, 0, sizeof(opts));
+	opts.head_idx = 2;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
+	opts.update = 1;
+	opts.verbose_update = 1;
+	opts.trivial_merges_only = 1;
+	opts.merge = 1;
+	trees[nr_trees] = parse_tree_indirect(common);
+	if (!trees[nr_trees++])
+		return -1;
+	trees[nr_trees] = parse_tree_indirect(head);
+	if (!trees[nr_trees++])
+		return -1;
+	trees[nr_trees] = parse_tree_indirect(one);
+	if (!trees[nr_trees++])
+		return -1;
+	opts.fn = threeway_merge;
+	cache_tree_free(&active_cache_tree);
+	for (i = 0; i < nr_trees; i++) {
+		parse_tree(trees[i]);
+		init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
+	}
+	if (unpack_trees(nr_trees, t, &opts))
+		return -1;
+	return 0;
+}
+
+static void write_tree_trivial(unsigned char *sha1)
+{
+	if (write_cache_as_tree(sha1, 0, NULL))
+		die("git write-tree failed to write a tree");
+}
+
+static int try_merge_strategy(const char *strategy, struct commit_list *common,
+			      const char *head_arg)
+{
+	const char **args;
+	int i = 0, x = 0, ret;
+	struct commit_list *j;
+	struct strbuf buf = STRBUF_INIT;
+	int index_fd;
+	struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+
+	index_fd = hold_locked_index(lock, 1);
+	refresh_cache(REFRESH_QUIET);
+	if (active_cache_changed &&
+			(write_cache(index_fd, active_cache, active_nr) ||
+			 commit_locked_index(lock)))
+		return error("Unable to write index.");
+	rollback_lock_file(lock);
+
+	if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
+		int clean;
+		struct commit *result;
+		struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+		int index_fd;
+		struct commit_list *reversed = NULL;
+		struct merge_options o;
+
+		if (remoteheads->next) {
+			error("Not handling anything other than two heads merge.");
+			return 2;
+		}
+
+		init_merge_options(&o);
+		if (!strcmp(strategy, "subtree"))
+			o.subtree_shift = "";
+
+		for (x = 0; x < xopts_nr; x++) {
+			if (!strcmp(xopts[x], "ours"))
+				o.recursive_variant = MERGE_RECURSIVE_OURS;
+			else if (!strcmp(xopts[x], "theirs"))
+				o.recursive_variant = MERGE_RECURSIVE_THEIRS;
+			else if (!strcmp(xopts[x], "subtree"))
+				o.subtree_shift = "";
+			else if (!prefixcmp(xopts[x], "subtree="))
+				o.subtree_shift = xopts[x]+8;
+			else
+				die("Unknown option for merge-recursive: -X%s", xopts[x]);
+		}
+
+		o.branch1 = head_arg;
+		o.branch2 = remoteheads->item->util;
+
+		for (j = common; j; j = j->next)
+			commit_list_insert(j->item, &reversed);
+
+		index_fd = hold_locked_index(lock, 1);
+		clean = merge_recursive(&o, lookup_commit(head),
+				remoteheads->item, reversed, &result);
+		if (active_cache_changed &&
+				(write_cache(index_fd, active_cache, active_nr) ||
+				 commit_locked_index(lock)))
+			die ("unable to write %s", get_index_file());
+		rollback_lock_file(lock);
+		return clean ? 0 : 1;
+	} else {
+		args = xmalloc((4 + xopts_nr + commit_list_count(common) +
+					commit_list_count(remoteheads)) * sizeof(char *));
+		strbuf_addf(&buf, "merge-%s", strategy);
+		args[i++] = buf.buf;
+		for (x = 0; x < xopts_nr; x++) {
+			char *s = xmalloc(strlen(xopts[x])+2+1);
+			strcpy(s, "--");
+			strcpy(s+2, xopts[x]);
+			args[i++] = s;
+		}
+		for (j = common; j; j = j->next)
+			args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
+		args[i++] = "--";
+		args[i++] = head_arg;
+		for (j = remoteheads; j; j = j->next)
+			args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
+		args[i] = NULL;
+		ret = run_command_v_opt(args, RUN_GIT_CMD);
+		strbuf_release(&buf);
+		i = 1;
+		for (x = 0; x < xopts_nr; x++)
+			free((void *)args[i++]);
+		for (j = common; j; j = j->next)
+			free((void *)args[i++]);
+		i += 2;
+		for (j = remoteheads; j; j = j->next)
+			free((void *)args[i++]);
+		free(args);
+		discard_cache();
+		if (read_cache() < 0)
+			die("failed to read the cache");
+		resolve_undo_clear();
+		return ret;
+	}
+}
+
+static void count_diff_files(struct diff_queue_struct *q,
+			     struct diff_options *opt, void *data)
+{
+	int *count = data;
+
+	(*count) += q->nr;
+}
+
+static int count_unmerged_entries(void)
+{
+	int i, ret = 0;
+
+	for (i = 0; i < active_nr; i++)
+		if (ce_stage(active_cache[i]))
+			ret++;
+
+	return ret;
+}
+
+static int checkout_fast_forward(unsigned char *head, unsigned char *remote)
+{
+	struct tree *trees[MAX_UNPACK_TREES];
+	struct unpack_trees_options opts;
+	struct tree_desc t[MAX_UNPACK_TREES];
+	int i, fd, nr_trees = 0;
+	struct dir_struct dir;
+	struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
+
+	refresh_cache(REFRESH_QUIET);
+
+	fd = hold_locked_index(lock_file, 1);
+
+	memset(&trees, 0, sizeof(trees));
+	memset(&opts, 0, sizeof(opts));
+	memset(&t, 0, sizeof(t));
+	memset(&dir, 0, sizeof(dir));
+	dir.flags |= DIR_SHOW_IGNORED;
+	dir.exclude_per_dir = ".gitignore";
+	opts.dir = &dir;
+
+	opts.head_idx = 1;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
+	opts.update = 1;
+	opts.verbose_update = 1;
+	opts.merge = 1;
+	opts.fn = twoway_merge;
+	opts.msgs = get_porcelain_error_msgs();
+
+	trees[nr_trees] = parse_tree_indirect(head);
+	if (!trees[nr_trees++])
+		return -1;
+	trees[nr_trees] = parse_tree_indirect(remote);
+	if (!trees[nr_trees++])
+		return -1;
+	for (i = 0; i < nr_trees; i++) {
+		parse_tree(trees[i]);
+		init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
+	}
+	if (unpack_trees(nr_trees, t, &opts))
+		return -1;
+	if (write_cache(fd, active_cache, active_nr) ||
+		commit_locked_index(lock_file))
+		die("unable to write new index file");
+	return 0;
+}
+
+static void split_merge_strategies(const char *string, struct strategy **list,
+				   int *nr, int *alloc)
+{
+	char *p, *q, *buf;
+
+	if (!string)
+		return;
+
+	buf = xstrdup(string);
+	q = buf;
+	for (;;) {
+		p = strchr(q, ' ');
+		if (!p) {
+			ALLOC_GROW(*list, *nr + 1, *alloc);
+			(*list)[(*nr)++].name = xstrdup(q);
+			free(buf);
+			return;
+		} else {
+			*p = '\0';
+			ALLOC_GROW(*list, *nr + 1, *alloc);
+			(*list)[(*nr)++].name = xstrdup(q);
+			q = ++p;
+		}
+	}
+}
+
+static void add_strategies(const char *string, unsigned attr)
+{
+	struct strategy *list = NULL;
+	int list_alloc = 0, list_nr = 0, i;
+
+	memset(&list, 0, sizeof(list));
+	split_merge_strategies(string, &list, &list_nr, &list_alloc);
+	if (list) {
+		for (i = 0; i < list_nr; i++)
+			append_strategy(get_strategy(list[i].name));
+		return;
+	}
+	for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
+		if (all_strategy[i].attr & attr)
+			append_strategy(&all_strategy[i]);
+
+}
+
+static int merge_trivial(void)
+{
+	unsigned char result_tree[20], result_commit[20];
+	struct commit_list *parent = xmalloc(sizeof(*parent));
+
+	write_tree_trivial(result_tree);
+	printf("Wonderful.\n");
+	parent->item = lookup_commit(head);
+	parent->next = xmalloc(sizeof(*parent->next));
+	parent->next->item = remoteheads->item;
+	parent->next->next = NULL;
+	commit_tree(merge_msg.buf, result_tree, parent, result_commit, NULL);
+	finish(result_commit, "In-index merge");
+	drop_save();
+	return 0;
+}
+
+static int finish_automerge(struct commit_list *common,
+			    unsigned char *result_tree,
+			    const char *wt_strategy)
+{
+	struct commit_list *parents = NULL, *j;
+	struct strbuf buf = STRBUF_INIT;
+	unsigned char result_commit[20];
+
+	free_commit_list(common);
+	if (allow_fast_forward) {
+		parents = remoteheads;
+		commit_list_insert(lookup_commit(head), &parents);
+		parents = reduce_heads(parents);
+	} else {
+		struct commit_list **pptr = &parents;
+
+		pptr = &commit_list_insert(lookup_commit(head),
+				pptr)->next;
+		for (j = remoteheads; j; j = j->next)
+			pptr = &commit_list_insert(j->item, pptr)->next;
+	}
+	free_commit_list(remoteheads);
+	strbuf_addch(&merge_msg, '\n');
+	commit_tree(merge_msg.buf, result_tree, parents, result_commit, NULL);
+	strbuf_addf(&buf, "Merge made by %s.", wt_strategy);
+	finish(result_commit, buf.buf);
+	strbuf_release(&buf);
+	drop_save();
+	return 0;
+}
+
+static int suggest_conflicts(void)
+{
+	FILE *fp;
+	int pos;
+
+	fp = fopen(git_path("MERGE_MSG"), "a");
+	if (!fp)
+		die_errno("Could not open '%s' for writing",
+			  git_path("MERGE_MSG"));
+	fprintf(fp, "\nConflicts:\n");
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+
+		if (ce_stage(ce)) {
+			fprintf(fp, "\t%s\n", ce->name);
+			while (pos + 1 < active_nr &&
+					!strcmp(ce->name,
+						active_cache[pos + 1]->name))
+				pos++;
+		}
+	}
+	fclose(fp);
+	rerere(allow_rerere_auto);
+	printf("Automatic merge failed; "
+			"fix conflicts and then commit the result.\n");
+	return 1;
+}
+
+static struct commit *is_old_style_invocation(int argc, const char **argv)
+{
+	struct commit *second_token = NULL;
+	if (argc > 2) {
+		unsigned char second_sha1[20];
+
+		if (get_sha1(argv[1], second_sha1))
+			return NULL;
+		second_token = lookup_commit_reference_gently(second_sha1, 0);
+		if (!second_token)
+			die("'%s' is not a commit", argv[1]);
+		if (hashcmp(second_token->object.sha1, head))
+			return NULL;
+	}
+	return second_token;
+}
+
+static int evaluate_result(void)
+{
+	int cnt = 0;
+	struct rev_info rev;
+
+	/* Check how many files differ. */
+	init_revisions(&rev, "");
+	setup_revisions(0, NULL, &rev, NULL);
+	rev.diffopt.output_format |=
+		DIFF_FORMAT_CALLBACK;
+	rev.diffopt.format_callback = count_diff_files;
+	rev.diffopt.format_callback_data = &cnt;
+	run_diff_files(&rev, 0);
+
+	/*
+	 * Check how many unmerged entries are
+	 * there.
+	 */
+	cnt += count_unmerged_entries();
+
+	return cnt;
+}
+
+int cmd_merge(int argc, const char **argv, const char *prefix)
+{
+	unsigned char result_tree[20];
+	struct strbuf buf = STRBUF_INIT;
+	const char *head_arg;
+	int flag, head_invalid = 0, i;
+	int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
+	struct commit_list *common = NULL;
+	const char *best_strategy = NULL, *wt_strategy = NULL;
+	struct commit_list **remotes = &remoteheads;
+
+	if (read_cache_unmerged()) {
+		die_resolve_conflict("merge");
+	}
+	if (file_exists(git_path("MERGE_HEAD"))) {
+		/*
+		 * There is no unmerged entry, don't advise 'git
+		 * add/rm <file>', just 'git commit'.
+		 */
+		if (advice_resolve_conflict)
+			die("You have not concluded your merge (MERGE_HEAD exists).\n"
+			    "Please, commit your changes before you can merge.");
+		else
+			die("You have not concluded your merge (MERGE_HEAD exists).");
+	}
+
+	resolve_undo_clear();
+	/*
+	 * Check if we are _not_ on a detached HEAD, i.e. if there is a
+	 * current branch.
+	 */
+	branch = resolve_ref("HEAD", head, 0, &flag);
+	if (branch && !prefixcmp(branch, "refs/heads/"))
+		branch += 11;
+	if (is_null_sha1(head))
+		head_invalid = 1;
+
+	git_config(git_merge_config, NULL);
+
+	/* for color.ui */
+	if (diff_use_color_default == -1)
+		diff_use_color_default = git_use_color_default;
+
+	argc = parse_options(argc, argv, prefix, builtin_merge_options,
+			builtin_merge_usage, 0);
+	if (verbosity < 0)
+		show_diffstat = 0;
+
+	if (squash) {
+		if (!allow_fast_forward)
+			die("You cannot combine --squash with --no-ff.");
+		option_commit = 0;
+	}
+
+	if (!allow_fast_forward && fast_forward_only)
+		die("You cannot combine --no-ff with --ff-only.");
+
+	if (!argc)
+		usage_with_options(builtin_merge_usage,
+			builtin_merge_options);
+
+	/*
+	 * This could be traditional "merge <msg> HEAD <commit>..."  and
+	 * the way we can tell it is to see if the second token is HEAD,
+	 * but some people might have misused the interface and used a
+	 * committish that is the same as HEAD there instead.
+	 * Traditional format never would have "-m" so it is an
+	 * additional safety measure to check for it.
+	 */
+
+	if (!have_message && is_old_style_invocation(argc, argv)) {
+		strbuf_addstr(&merge_msg, argv[0]);
+		head_arg = argv[1];
+		argv += 2;
+		argc -= 2;
+	} else if (head_invalid) {
+		struct object *remote_head;
+		/*
+		 * If the merged head is a valid one there is no reason
+		 * to forbid "git merge" into a branch yet to be born.
+		 * We do the same for "git pull".
+		 */
+		if (argc != 1)
+			die("Can merge only exactly one commit into "
+				"empty head");
+		if (squash)
+			die("Squash commit into empty head not supported yet");
+		if (!allow_fast_forward)
+			die("Non-fast-forward commit does not make sense into "
+			    "an empty head");
+		remote_head = peel_to_type(argv[0], 0, NULL, OBJ_COMMIT);
+		if (!remote_head)
+			die("%s - not something we can merge", argv[0]);
+		update_ref("initial pull", "HEAD", remote_head->sha1, NULL, 0,
+				DIE_ON_ERR);
+		reset_hard(remote_head->sha1, 0);
+		return 0;
+	} else {
+		struct strbuf msg = STRBUF_INIT;
+
+		/* We are invoked directly as the first-class UI. */
+		head_arg = "HEAD";
+
+		/*
+		 * All the rest are the commits being merged;
+		 * prepare the standard merge summary message to
+		 * be appended to the given message.  If remote
+		 * is invalid we will die later in the common
+		 * codepath so we discard the error in this
+		 * loop.
+		 */
+		if (!have_message) {
+			for (i = 0; i < argc; i++)
+				merge_name(argv[i], &msg);
+			fmt_merge_msg(option_log, &msg, &merge_msg);
+			if (merge_msg.len)
+				strbuf_setlen(&merge_msg, merge_msg.len-1);
+		}
+	}
+
+	if (head_invalid || !argc)
+		usage_with_options(builtin_merge_usage,
+			builtin_merge_options);
+
+	strbuf_addstr(&buf, "merge");
+	for (i = 0; i < argc; i++)
+		strbuf_addf(&buf, " %s", argv[i]);
+	setenv("GIT_REFLOG_ACTION", buf.buf, 0);
+	strbuf_reset(&buf);
+
+	for (i = 0; i < argc; i++) {
+		struct object *o;
+		struct commit *commit;
+
+		o = peel_to_type(argv[i], 0, NULL, OBJ_COMMIT);
+		if (!o)
+			die("%s - not something we can merge", argv[i]);
+		commit = lookup_commit(o->sha1);
+		commit->util = (void *)argv[i];
+		remotes = &commit_list_insert(commit, remotes)->next;
+
+		strbuf_addf(&buf, "GITHEAD_%s", sha1_to_hex(o->sha1));
+		setenv(buf.buf, argv[i], 1);
+		strbuf_reset(&buf);
+	}
+
+	if (!use_strategies) {
+		if (!remoteheads->next)
+			add_strategies(pull_twohead, DEFAULT_TWOHEAD);
+		else
+			add_strategies(pull_octopus, DEFAULT_OCTOPUS);
+	}
+
+	for (i = 0; i < use_strategies_nr; i++) {
+		if (use_strategies[i]->attr & NO_FAST_FORWARD)
+			allow_fast_forward = 0;
+		if (use_strategies[i]->attr & NO_TRIVIAL)
+			allow_trivial = 0;
+	}
+
+	if (!remoteheads->next)
+		common = get_merge_bases(lookup_commit(head),
+				remoteheads->item, 1);
+	else {
+		struct commit_list *list = remoteheads;
+		commit_list_insert(lookup_commit(head), &list);
+		common = get_octopus_merge_bases(list);
+		free(list);
+	}
+
+	update_ref("updating ORIG_HEAD", "ORIG_HEAD", head, NULL, 0,
+		DIE_ON_ERR);
+
+	if (!common)
+		; /* No common ancestors found. We need a real merge. */
+	else if (!remoteheads->next && !common->next &&
+			common->item == remoteheads->item) {
+		/*
+		 * If head can reach all the merge then we are up to date.
+		 * but first the most common case of merging one remote.
+		 */
+		finish_up_to_date("Already up-to-date.");
+		return 0;
+	} else if (allow_fast_forward && !remoteheads->next &&
+			!common->next &&
+			!hashcmp(common->item->object.sha1, head)) {
+		/* Again the most common case of merging one remote. */
+		struct strbuf msg = STRBUF_INIT;
+		struct object *o;
+		char hex[41];
+
+		strcpy(hex, find_unique_abbrev(head, DEFAULT_ABBREV));
+
+		if (verbosity >= 0)
+			printf("Updating %s..%s\n",
+				hex,
+				find_unique_abbrev(remoteheads->item->object.sha1,
+				DEFAULT_ABBREV));
+		strbuf_addstr(&msg, "Fast-forward");
+		if (have_message)
+			strbuf_addstr(&msg,
+				" (no commit created; -m option ignored)");
+		o = peel_to_type(sha1_to_hex(remoteheads->item->object.sha1),
+			0, NULL, OBJ_COMMIT);
+		if (!o)
+			return 1;
+
+		if (checkout_fast_forward(head, remoteheads->item->object.sha1))
+			return 1;
+
+		finish(o->sha1, msg.buf);
+		drop_save();
+		return 0;
+	} else if (!remoteheads->next && common->next)
+		;
+		/*
+		 * We are not doing octopus and not fast-forward.  Need
+		 * a real merge.
+		 */
+	else if (!remoteheads->next && !common->next && option_commit) {
+		/*
+		 * We are not doing octopus, not fast-forward, and have
+		 * only one common.
+		 */
+		refresh_cache(REFRESH_QUIET);
+		if (allow_trivial && !fast_forward_only) {
+			/* See if it is really trivial. */
+			git_committer_info(IDENT_ERROR_ON_NO_NAME);
+			printf("Trying really trivial in-index merge...\n");
+			if (!read_tree_trivial(common->item->object.sha1,
+					head, remoteheads->item->object.sha1))
+				return merge_trivial();
+			printf("Nope.\n");
+		}
+	} else {
+		/*
+		 * An octopus.  If we can reach all the remote we are up
+		 * to date.
+		 */
+		int up_to_date = 1;
+		struct commit_list *j;
+
+		for (j = remoteheads; j; j = j->next) {
+			struct commit_list *common_one;
+
+			/*
+			 * Here we *have* to calculate the individual
+			 * merge_bases again, otherwise "git merge HEAD^
+			 * HEAD^^" would be missed.
+			 */
+			common_one = get_merge_bases(lookup_commit(head),
+				j->item, 1);
+			if (hashcmp(common_one->item->object.sha1,
+				j->item->object.sha1)) {
+				up_to_date = 0;
+				break;
+			}
+		}
+		if (up_to_date) {
+			finish_up_to_date("Already up-to-date. Yeeah!");
+			return 0;
+		}
+	}
+
+	if (fast_forward_only)
+		die("Not possible to fast-forward, aborting.");
+
+	/* We are going to make a new commit. */
+	git_committer_info(IDENT_ERROR_ON_NO_NAME);
+
+	/*
+	 * At this point, we need a real merge.  No matter what strategy
+	 * we use, it would operate on the index, possibly affecting the
+	 * working tree, and when resolved cleanly, have the desired
+	 * tree in the index -- this means that the index must be in
+	 * sync with the head commit.  The strategies are responsible
+	 * to ensure this.
+	 */
+	if (use_strategies_nr != 1) {
+		/*
+		 * Stash away the local changes so that we can try more
+		 * than one.
+		 */
+		save_state();
+	} else {
+		memcpy(stash, null_sha1, 20);
+	}
+
+	for (i = 0; i < use_strategies_nr; i++) {
+		int ret;
+		if (i) {
+			printf("Rewinding the tree to pristine...\n");
+			restore_state();
+		}
+		if (use_strategies_nr != 1)
+			printf("Trying merge strategy %s...\n",
+				use_strategies[i]->name);
+		/*
+		 * Remember which strategy left the state in the working
+		 * tree.
+		 */
+		wt_strategy = use_strategies[i]->name;
+
+		ret = try_merge_strategy(use_strategies[i]->name,
+			common, head_arg);
+		if (!option_commit && !ret) {
+			merge_was_ok = 1;
+			/*
+			 * This is necessary here just to avoid writing
+			 * the tree, but later we will *not* exit with
+			 * status code 1 because merge_was_ok is set.
+			 */
+			ret = 1;
+		}
+
+		if (ret) {
+			/*
+			 * The backend exits with 1 when conflicts are
+			 * left to be resolved, with 2 when it does not
+			 * handle the given merge at all.
+			 */
+			if (ret == 1) {
+				int cnt = evaluate_result();
+
+				if (best_cnt <= 0 || cnt <= best_cnt) {
+					best_strategy = use_strategies[i]->name;
+					best_cnt = cnt;
+				}
+			}
+			if (merge_was_ok)
+				break;
+			else
+				continue;
+		}
+
+		/* Automerge succeeded. */
+		write_tree_trivial(result_tree);
+		automerge_was_ok = 1;
+		break;
+	}
+
+	/*
+	 * If we have a resulting tree, that means the strategy module
+	 * auto resolved the merge cleanly.
+	 */
+	if (automerge_was_ok)
+		return finish_automerge(common, result_tree, wt_strategy);
+
+	/*
+	 * Pick the result from the best strategy and have the user fix
+	 * it up.
+	 */
+	if (!best_strategy) {
+		restore_state();
+		if (use_strategies_nr > 1)
+			fprintf(stderr,
+				"No merge strategy handled the merge.\n");
+		else
+			fprintf(stderr, "Merge with strategy %s failed.\n",
+				use_strategies[0]->name);
+		return 2;
+	} else if (best_strategy == wt_strategy)
+		; /* We already have its result in the working tree. */
+	else {
+		printf("Rewinding the tree to pristine...\n");
+		restore_state();
+		printf("Using the %s to prepare resolving by hand.\n",
+			best_strategy);
+		try_merge_strategy(best_strategy, common, head_arg);
+	}
+
+	if (squash)
+		finish(NULL, NULL);
+	else {
+		int fd;
+		struct commit_list *j;
+
+		for (j = remoteheads; j; j = j->next)
+			strbuf_addf(&buf, "%s\n",
+				sha1_to_hex(j->item->object.sha1));
+		fd = open(git_path("MERGE_HEAD"), O_WRONLY | O_CREAT, 0666);
+		if (fd < 0)
+			die_errno("Could not open '%s' for writing",
+				  git_path("MERGE_HEAD"));
+		if (write_in_full(fd, buf.buf, buf.len) != buf.len)
+			die_errno("Could not write to '%s'", git_path("MERGE_HEAD"));
+		close(fd);
+		strbuf_addch(&merge_msg, '\n');
+		fd = open(git_path("MERGE_MSG"), O_WRONLY | O_CREAT, 0666);
+		if (fd < 0)
+			die_errno("Could not open '%s' for writing",
+				  git_path("MERGE_MSG"));
+		if (write_in_full(fd, merge_msg.buf, merge_msg.len) !=
+			merge_msg.len)
+			die_errno("Could not write to '%s'", git_path("MERGE_MSG"));
+		close(fd);
+		fd = open(git_path("MERGE_MODE"), O_WRONLY | O_CREAT | O_TRUNC, 0666);
+		if (fd < 0)
+			die_errno("Could not open '%s' for writing",
+				  git_path("MERGE_MODE"));
+		strbuf_reset(&buf);
+		if (!allow_fast_forward)
+			strbuf_addf(&buf, "no-ff");
+		if (write_in_full(fd, buf.buf, buf.len) != buf.len)
+			die_errno("Could not write to '%s'", git_path("MERGE_MODE"));
+		close(fd);
+	}
+
+	if (merge_was_ok) {
+		fprintf(stderr, "Automatic merge went well; "
+			"stopped before committing as requested\n");
+		return 0;
+	} else
+		return suggest_conflicts();
+}
diff --git a/builtin/mktag.c b/builtin/mktag.c
new file mode 100644
index 0000000..1cb0f3f
--- /dev/null
+++ b/builtin/mktag.c
@@ -0,0 +1,179 @@
+#include "cache.h"
+#include "tag.h"
+#include "exec_cmd.h"
+
+/*
+ * A signature file has a very simple fixed format: four lines
+ * of "object <sha1>" + "type <typename>" + "tag <tagname>" +
+ * "tagger <committer>", followed by a blank line, a free-form tag
+ * message and a signature block that git itself doesn't care about,
+ * but that can be verified with gpg or similar.
+ *
+ * The first four lines are guaranteed to be at least 83 bytes:
+ * "object <sha1>\n" is 48 bytes, "type tag\n" at 9 bytes is the
+ * shortest possible type-line, "tag .\n" at 6 bytes is the shortest
+ * single-character-tag line, and "tagger . <> 0 +0000\n" at 20 bytes is
+ * the shortest possible tagger-line.
+ */
+
+/*
+ * We refuse to tag something we can't verify. Just because.
+ */
+static int verify_object(const unsigned char *sha1, const char *expected_type)
+{
+	int ret = -1;
+	enum object_type type;
+	unsigned long size;
+	const unsigned char *repl;
+	void *buffer = read_sha1_file_repl(sha1, &type, &size, &repl);
+
+	if (buffer) {
+		if (type == type_from_string(expected_type))
+			ret = check_sha1_signature(repl, buffer, size, expected_type);
+		free(buffer);
+	}
+	return ret;
+}
+
+#ifdef NO_C99_FORMAT
+#define PD_FMT "%d"
+#else
+#define PD_FMT "%td"
+#endif
+
+static int verify_tag(char *buffer, unsigned long size)
+{
+	int typelen;
+	char type[20];
+	unsigned char sha1[20];
+	const char *object, *type_line, *tag_line, *tagger_line, *lb, *rb;
+	size_t len;
+
+	if (size < 84)
+		return error("wanna fool me ? you obviously got the size wrong !");
+
+	buffer[size] = 0;
+
+	/* Verify object line */
+	object = buffer;
+	if (memcmp(object, "object ", 7))
+		return error("char%d: does not start with \"object \"", 0);
+
+	if (get_sha1_hex(object + 7, sha1))
+		return error("char%d: could not get SHA1 hash", 7);
+
+	/* Verify type line */
+	type_line = object + 48;
+	if (memcmp(type_line - 1, "\ntype ", 6))
+		return error("char%d: could not find \"\\ntype \"", 47);
+
+	/* Verify tag-line */
+	tag_line = strchr(type_line, '\n');
+	if (!tag_line)
+		return error("char" PD_FMT ": could not find next \"\\n\"", type_line - buffer);
+	tag_line++;
+	if (memcmp(tag_line, "tag ", 4) || tag_line[4] == '\n')
+		return error("char" PD_FMT ": no \"tag \" found", tag_line - buffer);
+
+	/* Get the actual type */
+	typelen = tag_line - type_line - strlen("type \n");
+	if (typelen >= sizeof(type))
+		return error("char" PD_FMT ": type too long", type_line+5 - buffer);
+
+	memcpy(type, type_line+5, typelen);
+	type[typelen] = 0;
+
+	/* Verify that the object matches */
+	if (verify_object(sha1, type))
+		return error("char%d: could not verify object %s", 7, sha1_to_hex(sha1));
+
+	/* Verify the tag-name: we don't allow control characters or spaces in it */
+	tag_line += 4;
+	for (;;) {
+		unsigned char c = *tag_line++;
+		if (c == '\n')
+			break;
+		if (c > ' ')
+			continue;
+		return error("char" PD_FMT ": could not verify tag name", tag_line - buffer);
+	}
+
+	/* Verify the tagger line */
+	tagger_line = tag_line;
+
+	if (memcmp(tagger_line, "tagger ", 7))
+		return error("char" PD_FMT ": could not find \"tagger \"",
+			tagger_line - buffer);
+
+	/*
+	 * Check for correct form for name and email
+	 * i.e. " <" followed by "> " on _this_ line
+	 * No angle brackets within the name or email address fields.
+	 * No spaces within the email address field.
+	 */
+	tagger_line += 7;
+	if (!(lb = strstr(tagger_line, " <")) || !(rb = strstr(lb+2, "> ")) ||
+		strpbrk(tagger_line, "<>\n") != lb+1 ||
+		strpbrk(lb+2, "><\n ") != rb)
+		return error("char" PD_FMT ": malformed tagger field",
+			tagger_line - buffer);
+
+	/* Check for author name, at least one character, space is acceptable */
+	if (lb == tagger_line)
+		return error("char" PD_FMT ": missing tagger name",
+			tagger_line - buffer);
+
+	/* timestamp, 1 or more digits followed by space */
+	tagger_line = rb + 2;
+	if (!(len = strspn(tagger_line, "0123456789")))
+		return error("char" PD_FMT ": missing tag timestamp",
+			tagger_line - buffer);
+	tagger_line += len;
+	if (*tagger_line != ' ')
+		return error("char" PD_FMT ": malformed tag timestamp",
+			tagger_line - buffer);
+	tagger_line++;
+
+	/* timezone, 5 digits [+-]hhmm, max. 1400 */
+	if (!((tagger_line[0] == '+' || tagger_line[0] == '-') &&
+	      strspn(tagger_line+1, "0123456789") == 4 &&
+	      tagger_line[5] == '\n' && atoi(tagger_line+1) <= 1400))
+		return error("char" PD_FMT ": malformed tag timezone",
+			tagger_line - buffer);
+	tagger_line += 6;
+
+	/* Verify the blank line separating the header from the body */
+	if (*tagger_line != '\n')
+		return error("char" PD_FMT ": trailing garbage in tag header",
+			tagger_line - buffer);
+
+	/* The actual stuff afterwards we don't care about.. */
+	return 0;
+}
+
+#undef PD_FMT
+
+int cmd_mktag(int argc, const char **argv, const char *prefix)
+{
+	struct strbuf buf = STRBUF_INIT;
+	unsigned char result_sha1[20];
+
+	if (argc != 1)
+		usage("git mktag < signaturefile");
+
+	if (strbuf_read(&buf, 0, 4096) < 0) {
+		die_errno("could not read from stdin");
+	}
+
+	/* Verify it for some basic sanity: it needs to start with
+	   "object <sha1>\ntype\ntagger " */
+	if (verify_tag(buf.buf, buf.len) < 0)
+		die("invalid tag signature file");
+
+	if (write_sha1_file(buf.buf, buf.len, tag_type, result_sha1) < 0)
+		die("unable to write tag file");
+
+	strbuf_release(&buf);
+	printf("%s\n", sha1_to_hex(result_sha1));
+	return 0;
+}
diff --git a/builtin/mktree.c b/builtin/mktree.c
new file mode 100644
index 0000000..098395f
--- /dev/null
+++ b/builtin/mktree.c
@@ -0,0 +1,190 @@
+/*
+ * GIT - the stupid content tracker
+ *
+ * Copyright (c) Junio C Hamano, 2006, 2009
+ */
+#include "builtin.h"
+#include "quote.h"
+#include "tree.h"
+#include "parse-options.h"
+
+static struct treeent {
+	unsigned mode;
+	unsigned char sha1[20];
+	int len;
+	char name[FLEX_ARRAY];
+} **entries;
+static int alloc, used;
+
+static void append_to_tree(unsigned mode, unsigned char *sha1, char *path)
+{
+	struct treeent *ent;
+	int len = strlen(path);
+	if (strchr(path, '/'))
+		die("path %s contains slash", path);
+
+	if (alloc <= used) {
+		alloc = alloc_nr(used);
+		entries = xrealloc(entries, sizeof(*entries) * alloc);
+	}
+	ent = entries[used++] = xmalloc(sizeof(**entries) + len + 1);
+	ent->mode = mode;
+	ent->len = len;
+	hashcpy(ent->sha1, sha1);
+	memcpy(ent->name, path, len+1);
+}
+
+static int ent_compare(const void *a_, const void *b_)
+{
+	struct treeent *a = *(struct treeent **)a_;
+	struct treeent *b = *(struct treeent **)b_;
+	return base_name_compare(a->name, a->len, a->mode,
+				 b->name, b->len, b->mode);
+}
+
+static void write_tree(unsigned char *sha1)
+{
+	struct strbuf buf;
+	size_t size;
+	int i;
+
+	qsort(entries, used, sizeof(*entries), ent_compare);
+	for (size = i = 0; i < used; i++)
+		size += 32 + entries[i]->len;
+
+	strbuf_init(&buf, size);
+	for (i = 0; i < used; i++) {
+		struct treeent *ent = entries[i];
+		strbuf_addf(&buf, "%o %s%c", ent->mode, ent->name, '\0');
+		strbuf_add(&buf, ent->sha1, 20);
+	}
+
+	write_sha1_file(buf.buf, buf.len, tree_type, sha1);
+}
+
+static const char *mktree_usage[] = {
+	"git mktree [-z] [--missing] [--batch]",
+	NULL
+};
+
+static void mktree_line(char *buf, size_t len, int line_termination, int allow_missing)
+{
+	char *ptr, *ntr;
+	unsigned mode;
+	enum object_type mode_type; /* object type derived from mode */
+	enum object_type obj_type; /* object type derived from sha */
+	char *path;
+	unsigned char sha1[20];
+
+	ptr = buf;
+	/*
+	 * Read non-recursive ls-tree output format:
+	 *     mode SP type SP sha1 TAB name
+	 */
+	mode = strtoul(ptr, &ntr, 8);
+	if (ptr == ntr || !ntr || *ntr != ' ')
+		die("input format error: %s", buf);
+	ptr = ntr + 1; /* type */
+	ntr = strchr(ptr, ' ');
+	if (!ntr || buf + len <= ntr + 40 ||
+	    ntr[41] != '\t' ||
+	    get_sha1_hex(ntr + 1, sha1))
+		die("input format error: %s", buf);
+
+	/* It is perfectly normal if we do not have a commit from a submodule */
+	if (S_ISGITLINK(mode))
+		allow_missing = 1;
+
+
+	*ntr++ = 0; /* now at the beginning of SHA1 */
+
+	path = ntr + 41;  /* at the beginning of name */
+	if (line_termination && path[0] == '"') {
+		struct strbuf p_uq = STRBUF_INIT;
+		if (unquote_c_style(&p_uq, path, NULL))
+			die("invalid quoting");
+		path = strbuf_detach(&p_uq, NULL);
+	}
+
+	/*
+	 * Object type is redundantly derivable three ways.
+	 * These should all agree.
+	 */
+	mode_type = object_type(mode);
+	if (mode_type != type_from_string(ptr)) {
+		die("entry '%s' object type (%s) doesn't match mode type (%s)",
+			path, ptr, typename(mode_type));
+	}
+
+	/* Check the type of object identified by sha1 */
+	obj_type = sha1_object_info(sha1, NULL);
+	if (obj_type < 0) {
+		if (allow_missing) {
+			; /* no problem - missing objects are presumed to be of the right type */
+		} else {
+			die("entry '%s' object %s is unavailable", path, sha1_to_hex(sha1));
+		}
+	} else {
+		if (obj_type != mode_type) {
+			/*
+			 * The object exists but is of the wrong type.
+			 * This is a problem regardless of allow_missing
+			 * because the new tree entry will never be correct.
+			 */
+			die("entry '%s' object %s is a %s but specified type was (%s)",
+				path, sha1_to_hex(sha1), typename(obj_type), typename(mode_type));
+		}
+	}
+
+	append_to_tree(mode, sha1, path);
+}
+
+int cmd_mktree(int ac, const char **av, const char *prefix)
+{
+	struct strbuf sb = STRBUF_INIT;
+	unsigned char sha1[20];
+	int line_termination = '\n';
+	int allow_missing = 0;
+	int is_batch_mode = 0;
+	int got_eof = 0;
+
+	const struct option option[] = {
+		OPT_SET_INT('z', NULL, &line_termination, "input is NUL terminated", '\0'),
+		OPT_SET_INT( 0 , "missing", &allow_missing, "allow missing objects", 1),
+		OPT_SET_INT( 0 , "batch", &is_batch_mode, "allow creation of more than one tree", 1),
+		OPT_END()
+	};
+
+	ac = parse_options(ac, av, prefix, option, mktree_usage, 0);
+
+	while (!got_eof) {
+		while (1) {
+			if (strbuf_getline(&sb, stdin, line_termination) == EOF) {
+				got_eof = 1;
+				break;
+			}
+			if (sb.buf[0] == '\0') {
+				/* empty lines denote tree boundaries in batch mode */
+				if (is_batch_mode)
+					break;
+				die("input format error: (blank line only valid in batch mode)");
+			}
+			mktree_line(sb.buf, sb.len, line_termination, allow_missing);
+		}
+		if (is_batch_mode && got_eof && used < 1) {
+			/*
+			 * Execution gets here if the last tree entry is terminated with a
+			 * new-line.  The final new-line has been made optional to be
+			 * consistent with the original non-batch behaviour of mktree.
+			 */
+			; /* skip creating an empty tree */
+		} else {
+			write_tree(sha1);
+			puts(sha1_to_hex(sha1));
+			fflush(stdout);
+		}
+		used=0; /* reset tree entry buffer for re-use in batch mode */
+	}
+	strbuf_release(&sb);
+	exit(0);
+}
diff --git a/builtin/mv.c b/builtin/mv.c
new file mode 100644
index 0000000..c07f53b
--- /dev/null
+++ b/builtin/mv.c
@@ -0,0 +1,227 @@
+/*
+ * "git mv" builtin command
+ *
+ * Copyright (C) 2006 Johannes Schindelin
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "dir.h"
+#include "cache-tree.h"
+#include "string-list.h"
+#include "parse-options.h"
+
+static const char * const builtin_mv_usage[] = {
+	"git mv [options] <source>... <destination>",
+	NULL
+};
+
+static const char **copy_pathspec(const char *prefix, const char **pathspec,
+				  int count, int base_name)
+{
+	int i;
+	const char **result = xmalloc((count + 1) * sizeof(const char *));
+	memcpy(result, pathspec, count * sizeof(const char *));
+	result[count] = NULL;
+	for (i = 0; i < count; i++) {
+		int length = strlen(result[i]);
+		int to_copy = length;
+		while (to_copy > 0 && is_dir_sep(result[i][to_copy - 1]))
+			to_copy--;
+		if (to_copy != length || base_name) {
+			char *it = xmemdupz(result[i], to_copy);
+			result[i] = base_name ? strdup(basename(it)) : it;
+		}
+	}
+	return get_pathspec(prefix, result);
+}
+
+static const char *add_slash(const char *path)
+{
+	int len = strlen(path);
+	if (path[len - 1] != '/') {
+		char *with_slash = xmalloc(len + 2);
+		memcpy(with_slash, path, len);
+		with_slash[len++] = '/';
+		with_slash[len] = 0;
+		return with_slash;
+	}
+	return path;
+}
+
+static struct lock_file lock_file;
+
+int cmd_mv(int argc, const char **argv, const char *prefix)
+{
+	int i, newfd;
+	int verbose = 0, show_only = 0, force = 0, ignore_errors = 0;
+	struct option builtin_mv_options[] = {
+		OPT__DRY_RUN(&show_only),
+		OPT_BOOLEAN('f', "force", &force, "force move/rename even if target exists"),
+		OPT_BOOLEAN('k', NULL, &ignore_errors, "skip move/rename errors"),
+		OPT_END(),
+	};
+	const char **source, **destination, **dest_path;
+	enum update_mode { BOTH = 0, WORKING_DIRECTORY, INDEX } *modes;
+	struct stat st;
+	struct string_list src_for_dst = {NULL, 0, 0, 0};
+
+	git_config(git_default_config, NULL);
+
+	argc = parse_options(argc, argv, prefix, builtin_mv_options,
+			     builtin_mv_usage, 0);
+	if (--argc < 1)
+		usage_with_options(builtin_mv_usage, builtin_mv_options);
+
+	newfd = hold_locked_index(&lock_file, 1);
+	if (read_cache() < 0)
+		die("index file corrupt");
+
+	source = copy_pathspec(prefix, argv, argc, 0);
+	modes = xcalloc(argc, sizeof(enum update_mode));
+	dest_path = copy_pathspec(prefix, argv + argc, 1, 0);
+
+	if (dest_path[0][0] == '\0')
+		/* special case: "." was normalized to "" */
+		destination = copy_pathspec(dest_path[0], argv, argc, 1);
+	else if (!lstat(dest_path[0], &st) &&
+			S_ISDIR(st.st_mode)) {
+		dest_path[0] = add_slash(dest_path[0]);
+		destination = copy_pathspec(dest_path[0], argv, argc, 1);
+	} else {
+		if (argc != 1)
+			usage_with_options(builtin_mv_usage, builtin_mv_options);
+		destination = dest_path;
+	}
+
+	/* Checking */
+	for (i = 0; i < argc; i++) {
+		const char *src = source[i], *dst = destination[i];
+		int length, src_is_dir;
+		const char *bad = NULL;
+
+		if (show_only)
+			printf("Checking rename of '%s' to '%s'\n", src, dst);
+
+		length = strlen(src);
+		if (lstat(src, &st) < 0)
+			bad = "bad source";
+		else if (!strncmp(src, dst, length) &&
+				(dst[length] == 0 || dst[length] == '/')) {
+			bad = "can not move directory into itself";
+		} else if ((src_is_dir = S_ISDIR(st.st_mode))
+				&& lstat(dst, &st) == 0)
+			bad = "cannot move directory over file";
+		else if (src_is_dir) {
+			const char *src_w_slash = add_slash(src);
+			int len_w_slash = length + 1;
+			int first, last;
+
+			modes[i] = WORKING_DIRECTORY;
+
+			first = cache_name_pos(src_w_slash, len_w_slash);
+			if (first >= 0)
+				die ("Huh? %.*s is in index?",
+						len_w_slash, src_w_slash);
+
+			first = -1 - first;
+			for (last = first; last < active_nr; last++) {
+				const char *path = active_cache[last]->name;
+				if (strncmp(path, src_w_slash, len_w_slash))
+					break;
+			}
+			free((char *)src_w_slash);
+
+			if (last - first < 1)
+				bad = "source directory is empty";
+			else {
+				int j, dst_len;
+
+				if (last - first > 0) {
+					source = xrealloc(source,
+							(argc + last - first)
+							* sizeof(char *));
+					destination = xrealloc(destination,
+							(argc + last - first)
+							* sizeof(char *));
+					modes = xrealloc(modes,
+							(argc + last - first)
+							* sizeof(enum update_mode));
+				}
+
+				dst = add_slash(dst);
+				dst_len = strlen(dst);
+
+				for (j = 0; j < last - first; j++) {
+					const char *path =
+						active_cache[first + j]->name;
+					source[argc + j] = path;
+					destination[argc + j] =
+						prefix_path(dst, dst_len,
+							path + length + 1);
+					modes[argc + j] = INDEX;
+				}
+				argc += last - first;
+			}
+		} else if (cache_name_pos(src, length) < 0)
+			bad = "not under version control";
+		else if (lstat(dst, &st) == 0) {
+			bad = "destination exists";
+			if (force) {
+				/*
+				 * only files can overwrite each other:
+				 * check both source and destination
+				 */
+				if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
+					warning("%s; will overwrite!", bad);
+					bad = NULL;
+				} else
+					bad = "Cannot overwrite";
+			}
+		} else if (string_list_has_string(&src_for_dst, dst))
+			bad = "multiple sources for the same target";
+		else
+			string_list_insert(dst, &src_for_dst);
+
+		if (bad) {
+			if (ignore_errors) {
+				if (--argc > 0) {
+					memmove(source + i, source + i + 1,
+						(argc - i) * sizeof(char *));
+					memmove(destination + i,
+						destination + i + 1,
+						(argc - i) * sizeof(char *));
+					i--;
+				}
+			} else
+				die ("%s, source=%s, destination=%s",
+				     bad, src, dst);
+		}
+	}
+
+	for (i = 0; i < argc; i++) {
+		const char *src = source[i], *dst = destination[i];
+		enum update_mode mode = modes[i];
+		int pos;
+		if (show_only || verbose)
+			printf("Renaming %s to %s\n", src, dst);
+		if (!show_only && mode != INDEX &&
+				rename(src, dst) < 0 && !ignore_errors)
+			die_errno ("renaming '%s' failed", src);
+
+		if (mode == WORKING_DIRECTORY)
+			continue;
+
+		pos = cache_name_pos(src, strlen(src));
+		assert(pos >= 0);
+		if (!show_only)
+			rename_cache_entry_at(pos, dst);
+	}
+
+	if (active_cache_changed) {
+		if (write_cache(newfd, active_cache, active_nr) ||
+		    commit_locked_index(&lock_file))
+			die("Unable to write new index file");
+	}
+
+	return 0;
+}
diff --git a/builtin/name-rev.c b/builtin/name-rev.c
new file mode 100644
index 0000000..06a38ac
--- /dev/null
+++ b/builtin/name-rev.c
@@ -0,0 +1,305 @@
+#include "builtin.h"
+#include "cache.h"
+#include "commit.h"
+#include "tag.h"
+#include "refs.h"
+#include "parse-options.h"
+
+#define CUTOFF_DATE_SLOP 86400 /* one day */
+
+typedef struct rev_name {
+	const char *tip_name;
+	int generation;
+	int distance;
+} rev_name;
+
+static long cutoff = LONG_MAX;
+
+/* How many generations are maximally preferred over _one_ merge traversal? */
+#define MERGE_TRAVERSAL_WEIGHT 65535
+
+static void name_rev(struct commit *commit,
+		const char *tip_name, int generation, int distance,
+		int deref)
+{
+	struct rev_name *name = (struct rev_name *)commit->util;
+	struct commit_list *parents;
+	int parent_number = 1;
+
+	if (!commit->object.parsed)
+		parse_commit(commit);
+
+	if (commit->date < cutoff)
+		return;
+
+	if (deref) {
+		char *new_name = xmalloc(strlen(tip_name)+3);
+		strcpy(new_name, tip_name);
+		strcat(new_name, "^0");
+		tip_name = new_name;
+
+		if (generation)
+			die("generation: %d, but deref?", generation);
+	}
+
+	if (name == NULL) {
+		name = xmalloc(sizeof(rev_name));
+		commit->util = name;
+		goto copy_data;
+	} else if (name->distance > distance) {
+copy_data:
+		name->tip_name = tip_name;
+		name->generation = generation;
+		name->distance = distance;
+	} else
+		return;
+
+	for (parents = commit->parents;
+			parents;
+			parents = parents->next, parent_number++) {
+		if (parent_number > 1) {
+			int len = strlen(tip_name);
+			char *new_name = xmalloc(len +
+				1 + decimal_length(generation) +  /* ~<n> */
+				1 + 2 +				  /* ^NN */
+				1);
+
+			if (len > 2 && !strcmp(tip_name + len - 2, "^0"))
+				len -= 2;
+			if (generation > 0)
+				sprintf(new_name, "%.*s~%d^%d", len, tip_name,
+						generation, parent_number);
+			else
+				sprintf(new_name, "%.*s^%d", len, tip_name,
+						parent_number);
+
+			name_rev(parents->item, new_name, 0,
+				distance + MERGE_TRAVERSAL_WEIGHT, 0);
+		} else {
+			name_rev(parents->item, tip_name, generation + 1,
+				distance + 1, 0);
+		}
+	}
+}
+
+struct name_ref_data {
+	int tags_only;
+	int name_only;
+	const char *ref_filter;
+};
+
+static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
+{
+	struct object *o = parse_object(sha1);
+	struct name_ref_data *data = cb_data;
+	int deref = 0;
+
+	if (data->tags_only && prefixcmp(path, "refs/tags/"))
+		return 0;
+
+	if (data->ref_filter && fnmatch(data->ref_filter, path, 0))
+		return 0;
+
+	while (o && o->type == OBJ_TAG) {
+		struct tag *t = (struct tag *) o;
+		if (!t->tagged)
+			break; /* broken repository */
+		o = parse_object(t->tagged->sha1);
+		deref = 1;
+	}
+	if (o && o->type == OBJ_COMMIT) {
+		struct commit *commit = (struct commit *)o;
+
+		if (!prefixcmp(path, "refs/heads/"))
+			path = path + 11;
+		else if (data->tags_only
+		    && data->name_only
+		    && !prefixcmp(path, "refs/tags/"))
+			path = path + 10;
+		else if (!prefixcmp(path, "refs/"))
+			path = path + 5;
+
+		name_rev(commit, xstrdup(path), 0, 0, deref);
+	}
+	return 0;
+}
+
+/* returns a static buffer */
+static const char *get_rev_name(const struct object *o)
+{
+	static char buffer[1024];
+	struct rev_name *n;
+	struct commit *c;
+
+	if (o->type != OBJ_COMMIT)
+		return NULL;
+	c = (struct commit *) o;
+	n = c->util;
+	if (!n)
+		return NULL;
+
+	if (!n->generation)
+		return n->tip_name;
+	else {
+		int len = strlen(n->tip_name);
+		if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
+			len -= 2;
+		snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
+				n->generation);
+
+		return buffer;
+	}
+}
+
+static void show_name(const struct object *obj,
+		      const char *caller_name,
+		      int always, int allow_undefined, int name_only)
+{
+	const char *name;
+	const unsigned char *sha1 = obj->sha1;
+
+	if (!name_only)
+		printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
+	name = get_rev_name(obj);
+	if (name)
+		printf("%s\n", name);
+	else if (allow_undefined)
+		printf("undefined\n");
+	else if (always)
+		printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
+	else
+		die("cannot describe '%s'", sha1_to_hex(sha1));
+}
+
+static char const * const name_rev_usage[] = {
+	"git name-rev [options] ( --all | --stdin | <commit>... )",
+	NULL
+};
+
+static void name_rev_line(char *p, struct name_ref_data *data)
+{
+	int forty = 0;
+	char *p_start;
+	for (p_start = p; *p; p++) {
+#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
+		if (!ishex(*p))
+			forty = 0;
+		else if (++forty == 40 &&
+			 !ishex(*(p+1))) {
+			unsigned char sha1[40];
+			const char *name = NULL;
+			char c = *(p+1);
+			int p_len = p - p_start + 1;
+
+			forty = 0;
+
+			*(p+1) = 0;
+			if (!get_sha1(p - 39, sha1)) {
+				struct object *o =
+					lookup_object(sha1);
+				if (o)
+					name = get_rev_name(o);
+			}
+			*(p+1) = c;
+
+			if (!name)
+				continue;
+
+			if (data->name_only)
+				printf("%.*s%s", p_len - 40, p_start, name);
+			else
+				printf("%.*s (%s)", p_len, p_start, name);
+			p_start = p + 1;
+		}
+	}
+
+	/* flush */
+	if (p_start != p)
+		fwrite(p_start, p - p_start, 1, stdout);
+}
+
+int cmd_name_rev(int argc, const char **argv, const char *prefix)
+{
+	struct object_array revs = { 0, 0, NULL };
+	int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0;
+	struct name_ref_data data = { 0, 0, NULL };
+	struct option opts[] = {
+		OPT_BOOLEAN(0, "name-only", &data.name_only, "print only names (no SHA-1)"),
+		OPT_BOOLEAN(0, "tags", &data.tags_only, "only use tags to name the commits"),
+		OPT_STRING(0, "refs", &data.ref_filter, "pattern",
+				   "only use refs matching <pattern>"),
+		OPT_GROUP(""),
+		OPT_BOOLEAN(0, "all", &all, "list all commits reachable from all refs"),
+		OPT_BOOLEAN(0, "stdin", &transform_stdin, "read from stdin"),
+		OPT_BOOLEAN(0, "undefined", &allow_undefined, "allow to print `undefined` names"),
+		OPT_BOOLEAN(0, "always",     &always,
+			   "show abbreviated commit object as fallback"),
+		OPT_END(),
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
+	if (!!all + !!transform_stdin + !!argc > 1) {
+		error("Specify either a list, or --all, not both!");
+		usage_with_options(name_rev_usage, opts);
+	}
+	if (all || transform_stdin)
+		cutoff = 0;
+
+	for (; argc; argc--, argv++) {
+		unsigned char sha1[20];
+		struct object *o;
+		struct commit *commit;
+
+		if (get_sha1(*argv, sha1)) {
+			fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
+					*argv);
+			continue;
+		}
+
+		o = deref_tag(parse_object(sha1), *argv, 0);
+		if (!o || o->type != OBJ_COMMIT) {
+			fprintf(stderr, "Could not get commit for %s. Skipping.\n",
+					*argv);
+			continue;
+		}
+
+		commit = (struct commit *)o;
+		if (cutoff > commit->date)
+			cutoff = commit->date;
+		add_object_array((struct object *)commit, *argv, &revs);
+	}
+
+	if (cutoff)
+		cutoff = cutoff - CUTOFF_DATE_SLOP;
+	for_each_ref(name_ref, &data);
+
+	if (transform_stdin) {
+		char buffer[2048];
+
+		while (!feof(stdin)) {
+			char *p = fgets(buffer, sizeof(buffer), stdin);
+			if (!p)
+				break;
+			name_rev_line(p, &data);
+		}
+	} else if (all) {
+		int i, max;
+
+		max = get_max_object_index();
+		for (i = 0; i < max; i++) {
+			struct object *obj = get_indexed_object(i);
+			if (!obj)
+				continue;
+			show_name(obj, NULL,
+				  always, allow_undefined, data.name_only);
+		}
+	} else {
+		int i;
+		for (i = 0; i < revs.nr; i++)
+			show_name(revs.objects[i].item, revs.objects[i].name,
+				  always, allow_undefined, data.name_only);
+	}
+
+	return 0;
+}
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
new file mode 100644
index 0000000..9780258
--- /dev/null
+++ b/builtin/pack-objects.c
@@ -0,0 +1,2334 @@
+#include "builtin.h"
+#include "cache.h"
+#include "attr.h"
+#include "object.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree.h"
+#include "delta.h"
+#include "pack.h"
+#include "pack-revindex.h"
+#include "csum-file.h"
+#include "tree-walk.h"
+#include "diff.h"
+#include "revision.h"
+#include "list-objects.h"
+#include "progress.h"
+#include "refs.h"
+
+#ifndef NO_PTHREADS
+#include "thread-utils.h"
+#include <pthread.h>
+#endif
+
+static const char pack_usage[] =
+  "git pack-objects [{ -q | --progress | --all-progress }]\n"
+  "        [--all-progress-implied]\n"
+  "        [--max-pack-size=N] [--local] [--incremental]\n"
+  "        [--window=N] [--window-memory=N] [--depth=N]\n"
+  "        [--no-reuse-delta] [--no-reuse-object] [--delta-base-offset]\n"
+  "        [--threads=N] [--non-empty] [--revs [--unpacked | --all]*]\n"
+  "        [--reflog] [--stdout | base-name] [--include-tag]\n"
+  "        [--keep-unreachable | --unpack-unreachable \n"
+  "        [<ref-list | <object-list]";
+
+struct object_entry {
+	struct pack_idx_entry idx;
+	unsigned long size;	/* uncompressed size */
+	struct packed_git *in_pack; 	/* already in pack */
+	off_t in_pack_offset;
+	struct object_entry *delta;	/* delta base object */
+	struct object_entry *delta_child; /* deltified objects who bases me */
+	struct object_entry *delta_sibling; /* other deltified objects who
+					     * uses the same base as me
+					     */
+	void *delta_data;	/* cached delta (uncompressed) */
+	unsigned long delta_size;	/* delta data size (uncompressed) */
+	unsigned long z_delta_size;	/* delta data size (compressed) */
+	unsigned int hash;	/* name hint hash */
+	enum object_type type;
+	enum object_type in_pack_type;	/* could be delta */
+	unsigned char in_pack_header_size;
+	unsigned char preferred_base; /* we do not pack this, but is available
+				       * to be used as the base object to delta
+				       * objects against.
+				       */
+	unsigned char no_try_delta;
+};
+
+/*
+ * Objects we are going to pack are collected in objects array (dynamically
+ * expanded).  nr_objects & nr_alloc controls this array.  They are stored
+ * in the order we see -- typically rev-list --objects order that gives us
+ * nice "minimum seek" order.
+ */
+static struct object_entry *objects;
+static struct pack_idx_entry **written_list;
+static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
+
+static int non_empty;
+static int reuse_delta = 1, reuse_object = 1;
+static int keep_unreachable, unpack_unreachable, include_tag;
+static int local;
+static int incremental;
+static int ignore_packed_keep;
+static int allow_ofs_delta;
+static const char *base_name;
+static int progress = 1;
+static int window = 10;
+static unsigned long pack_size_limit, pack_size_limit_cfg;
+static int depth = 50;
+static int delta_search_threads;
+static int pack_to_stdout;
+static int num_preferred_base;
+static struct progress *progress_state;
+static int pack_compression_level = Z_DEFAULT_COMPRESSION;
+static int pack_compression_seen;
+
+static unsigned long delta_cache_size = 0;
+static unsigned long max_delta_cache_size = 256 * 1024 * 1024;
+static unsigned long cache_max_small_delta_size = 1000;
+
+static unsigned long window_memory_limit = 0;
+
+/*
+ * The object names in objects array are hashed with this hashtable,
+ * to help looking up the entry by object name.
+ * This hashtable is built after all the objects are seen.
+ */
+static int *object_ix;
+static int object_ix_hashsz;
+
+/*
+ * stats
+ */
+static uint32_t written, written_delta;
+static uint32_t reused, reused_delta;
+
+
+static void *get_delta(struct object_entry *entry)
+{
+	unsigned long size, base_size, delta_size;
+	void *buf, *base_buf, *delta_buf;
+	enum object_type type;
+
+	buf = read_sha1_file(entry->idx.sha1, &type, &size);
+	if (!buf)
+		die("unable to read %s", sha1_to_hex(entry->idx.sha1));
+	base_buf = read_sha1_file(entry->delta->idx.sha1, &type, &base_size);
+	if (!base_buf)
+		die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
+	delta_buf = diff_delta(base_buf, base_size,
+			       buf, size, &delta_size, 0);
+	if (!delta_buf || delta_size != entry->delta_size)
+		die("delta size changed");
+	free(buf);
+	free(base_buf);
+	return delta_buf;
+}
+
+static unsigned long do_compress(void **pptr, unsigned long size)
+{
+	z_stream stream;
+	void *in, *out;
+	unsigned long maxsize;
+
+	memset(&stream, 0, sizeof(stream));
+	deflateInit(&stream, pack_compression_level);
+	maxsize = deflateBound(&stream, size);
+
+	in = *pptr;
+	out = xmalloc(maxsize);
+	*pptr = out;
+
+	stream.next_in = in;
+	stream.avail_in = size;
+	stream.next_out = out;
+	stream.avail_out = maxsize;
+	while (deflate(&stream, Z_FINISH) == Z_OK)
+		; /* nothing */
+	deflateEnd(&stream);
+
+	free(in);
+	return stream.total_out;
+}
+
+/*
+ * we are going to reuse the existing object data as is.  make
+ * sure it is not corrupt.
+ */
+static int check_pack_inflate(struct packed_git *p,
+		struct pack_window **w_curs,
+		off_t offset,
+		off_t len,
+		unsigned long expect)
+{
+	z_stream stream;
+	unsigned char fakebuf[4096], *in;
+	int st;
+
+	memset(&stream, 0, sizeof(stream));
+	git_inflate_init(&stream);
+	do {
+		in = use_pack(p, w_curs, offset, &stream.avail_in);
+		stream.next_in = in;
+		stream.next_out = fakebuf;
+		stream.avail_out = sizeof(fakebuf);
+		st = git_inflate(&stream, Z_FINISH);
+		offset += stream.next_in - in;
+	} while (st == Z_OK || st == Z_BUF_ERROR);
+	git_inflate_end(&stream);
+	return (st == Z_STREAM_END &&
+		stream.total_out == expect &&
+		stream.total_in == len) ? 0 : -1;
+}
+
+static void copy_pack_data(struct sha1file *f,
+		struct packed_git *p,
+		struct pack_window **w_curs,
+		off_t offset,
+		off_t len)
+{
+	unsigned char *in;
+	unsigned int avail;
+
+	while (len) {
+		in = use_pack(p, w_curs, offset, &avail);
+		if (avail > len)
+			avail = (unsigned int)len;
+		sha1write(f, in, avail);
+		offset += avail;
+		len -= avail;
+	}
+}
+
+static unsigned long write_object(struct sha1file *f,
+				  struct object_entry *entry,
+				  off_t write_offset)
+{
+	unsigned long size, limit, datalen;
+	void *buf;
+	unsigned char header[10], dheader[10];
+	unsigned hdrlen;
+	enum object_type type;
+	int usable_delta, to_reuse;
+
+	if (!pack_to_stdout)
+		crc32_begin(f);
+
+	type = entry->type;
+
+	/* apply size limit if limited packsize and not first object */
+	if (!pack_size_limit || !nr_written)
+		limit = 0;
+	else if (pack_size_limit <= write_offset)
+		/*
+		 * the earlier object did not fit the limit; avoid
+		 * mistaking this with unlimited (i.e. limit = 0).
+		 */
+		limit = 1;
+	else
+		limit = pack_size_limit - write_offset;
+
+	if (!entry->delta)
+		usable_delta = 0;	/* no delta */
+	else if (!pack_size_limit)
+	       usable_delta = 1;	/* unlimited packfile */
+	else if (entry->delta->idx.offset == (off_t)-1)
+		usable_delta = 0;	/* base was written to another pack */
+	else if (entry->delta->idx.offset)
+		usable_delta = 1;	/* base already exists in this pack */
+	else
+		usable_delta = 0;	/* base could end up in another pack */
+
+	if (!reuse_object)
+		to_reuse = 0;	/* explicit */
+	else if (!entry->in_pack)
+		to_reuse = 0;	/* can't reuse what we don't have */
+	else if (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA)
+				/* check_object() decided it for us ... */
+		to_reuse = usable_delta;
+				/* ... but pack split may override that */
+	else if (type != entry->in_pack_type)
+		to_reuse = 0;	/* pack has delta which is unusable */
+	else if (entry->delta)
+		to_reuse = 0;	/* we want to pack afresh */
+	else
+		to_reuse = 1;	/* we have it in-pack undeltified,
+				 * and we do not need to deltify it.
+				 */
+
+	if (!to_reuse) {
+		no_reuse:
+		if (!usable_delta) {
+			buf = read_sha1_file(entry->idx.sha1, &type, &size);
+			if (!buf)
+				die("unable to read %s", sha1_to_hex(entry->idx.sha1));
+			/*
+			 * make sure no cached delta data remains from a
+			 * previous attempt before a pack split occurred.
+			 */
+			free(entry->delta_data);
+			entry->delta_data = NULL;
+			entry->z_delta_size = 0;
+		} else if (entry->delta_data) {
+			size = entry->delta_size;
+			buf = entry->delta_data;
+			entry->delta_data = NULL;
+			type = (allow_ofs_delta && entry->delta->idx.offset) ?
+				OBJ_OFS_DELTA : OBJ_REF_DELTA;
+		} else {
+			buf = get_delta(entry);
+			size = entry->delta_size;
+			type = (allow_ofs_delta && entry->delta->idx.offset) ?
+				OBJ_OFS_DELTA : OBJ_REF_DELTA;
+		}
+
+		if (entry->z_delta_size)
+			datalen = entry->z_delta_size;
+		else
+			datalen = do_compress(&buf, size);
+
+		/*
+		 * The object header is a byte of 'type' followed by zero or
+		 * more bytes of length.
+		 */
+		hdrlen = encode_in_pack_object_header(type, size, header);
+
+		if (type == OBJ_OFS_DELTA) {
+			/*
+			 * Deltas with relative base contain an additional
+			 * encoding of the relative offset for the delta
+			 * base from this object's position in the pack.
+			 */
+			off_t ofs = entry->idx.offset - entry->delta->idx.offset;
+			unsigned pos = sizeof(dheader) - 1;
+			dheader[pos] = ofs & 127;
+			while (ofs >>= 7)
+				dheader[--pos] = 128 | (--ofs & 127);
+			if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+				free(buf);
+				return 0;
+			}
+			sha1write(f, header, hdrlen);
+			sha1write(f, dheader + pos, sizeof(dheader) - pos);
+			hdrlen += sizeof(dheader) - pos;
+		} else if (type == OBJ_REF_DELTA) {
+			/*
+			 * Deltas with a base reference contain
+			 * an additional 20 bytes for the base sha1.
+			 */
+			if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+				free(buf);
+				return 0;
+			}
+			sha1write(f, header, hdrlen);
+			sha1write(f, entry->delta->idx.sha1, 20);
+			hdrlen += 20;
+		} else {
+			if (limit && hdrlen + datalen + 20 >= limit) {
+				free(buf);
+				return 0;
+			}
+			sha1write(f, header, hdrlen);
+		}
+		sha1write(f, buf, datalen);
+		free(buf);
+	}
+	else {
+		struct packed_git *p = entry->in_pack;
+		struct pack_window *w_curs = NULL;
+		struct revindex_entry *revidx;
+		off_t offset;
+
+		if (entry->delta)
+			type = (allow_ofs_delta && entry->delta->idx.offset) ?
+				OBJ_OFS_DELTA : OBJ_REF_DELTA;
+		hdrlen = encode_in_pack_object_header(type, entry->size, header);
+
+		offset = entry->in_pack_offset;
+		revidx = find_pack_revindex(p, offset);
+		datalen = revidx[1].offset - offset;
+		if (!pack_to_stdout && p->index_version > 1 &&
+		    check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) {
+			error("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
+			unuse_pack(&w_curs);
+			goto no_reuse;
+		}
+
+		offset += entry->in_pack_header_size;
+		datalen -= entry->in_pack_header_size;
+		if (!pack_to_stdout && p->index_version == 1 &&
+		    check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) {
+			error("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
+			unuse_pack(&w_curs);
+			goto no_reuse;
+		}
+
+		if (type == OBJ_OFS_DELTA) {
+			off_t ofs = entry->idx.offset - entry->delta->idx.offset;
+			unsigned pos = sizeof(dheader) - 1;
+			dheader[pos] = ofs & 127;
+			while (ofs >>= 7)
+				dheader[--pos] = 128 | (--ofs & 127);
+			if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+				unuse_pack(&w_curs);
+				return 0;
+			}
+			sha1write(f, header, hdrlen);
+			sha1write(f, dheader + pos, sizeof(dheader) - pos);
+			hdrlen += sizeof(dheader) - pos;
+			reused_delta++;
+		} else if (type == OBJ_REF_DELTA) {
+			if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+				unuse_pack(&w_curs);
+				return 0;
+			}
+			sha1write(f, header, hdrlen);
+			sha1write(f, entry->delta->idx.sha1, 20);
+			hdrlen += 20;
+			reused_delta++;
+		} else {
+			if (limit && hdrlen + datalen + 20 >= limit) {
+				unuse_pack(&w_curs);
+				return 0;
+			}
+			sha1write(f, header, hdrlen);
+		}
+		copy_pack_data(f, p, &w_curs, offset, datalen);
+		unuse_pack(&w_curs);
+		reused++;
+	}
+	if (usable_delta)
+		written_delta++;
+	written++;
+	if (!pack_to_stdout)
+		entry->idx.crc32 = crc32_end(f);
+	return hdrlen + datalen;
+}
+
+static int write_one(struct sha1file *f,
+			       struct object_entry *e,
+			       off_t *offset)
+{
+	unsigned long size;
+
+	/* offset is non zero if object is written already. */
+	if (e->idx.offset || e->preferred_base)
+		return -1;
+
+	/* if we are deltified, write out base object first. */
+	if (e->delta && !write_one(f, e->delta, offset))
+		return 0;
+
+	e->idx.offset = *offset;
+	size = write_object(f, e, *offset);
+	if (!size) {
+		e->idx.offset = 0;
+		return 0;
+	}
+	written_list[nr_written++] = &e->idx;
+
+	/* make sure off_t is sufficiently large not to wrap */
+	if (*offset > *offset + size)
+		die("pack too large for current definition of off_t");
+	*offset += size;
+	return 1;
+}
+
+static void write_pack_file(void)
+{
+	uint32_t i = 0, j;
+	struct sha1file *f;
+	off_t offset;
+	struct pack_header hdr;
+	uint32_t nr_remaining = nr_result;
+	time_t last_mtime = 0;
+
+	if (progress > pack_to_stdout)
+		progress_state = start_progress("Writing objects", nr_result);
+	written_list = xmalloc(nr_objects * sizeof(*written_list));
+
+	do {
+		unsigned char sha1[20];
+		char *pack_tmp_name = NULL;
+
+		if (pack_to_stdout) {
+			f = sha1fd_throughput(1, "<stdout>", progress_state);
+		} else {
+			char tmpname[PATH_MAX];
+			int fd;
+			fd = odb_mkstemp(tmpname, sizeof(tmpname),
+					 "pack/tmp_pack_XXXXXX");
+			pack_tmp_name = xstrdup(tmpname);
+			f = sha1fd(fd, pack_tmp_name);
+		}
+
+		hdr.hdr_signature = htonl(PACK_SIGNATURE);
+		hdr.hdr_version = htonl(PACK_VERSION);
+		hdr.hdr_entries = htonl(nr_remaining);
+		sha1write(f, &hdr, sizeof(hdr));
+		offset = sizeof(hdr);
+		nr_written = 0;
+		for (; i < nr_objects; i++) {
+			if (!write_one(f, objects + i, &offset))
+				break;
+			display_progress(progress_state, written);
+		}
+
+		/*
+		 * Did we write the wrong # entries in the header?
+		 * If so, rewrite it like in fast-import
+		 */
+		if (pack_to_stdout) {
+			sha1close(f, sha1, CSUM_CLOSE);
+		} else if (nr_written == nr_remaining) {
+			sha1close(f, sha1, CSUM_FSYNC);
+		} else {
+			int fd = sha1close(f, sha1, 0);
+			fixup_pack_header_footer(fd, sha1, pack_tmp_name,
+						 nr_written, sha1, offset);
+			close(fd);
+		}
+
+		if (!pack_to_stdout) {
+			struct stat st;
+			const char *idx_tmp_name;
+			char tmpname[PATH_MAX];
+
+			idx_tmp_name = write_idx_file(NULL, written_list,
+						      nr_written, sha1);
+
+			snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
+				 base_name, sha1_to_hex(sha1));
+			free_pack_by_name(tmpname);
+			if (adjust_shared_perm(pack_tmp_name))
+				die_errno("unable to make temporary pack file readable");
+			if (rename(pack_tmp_name, tmpname))
+				die_errno("unable to rename temporary pack file");
+
+			/*
+			 * Packs are runtime accessed in their mtime
+			 * order since newer packs are more likely to contain
+			 * younger objects.  So if we are creating multiple
+			 * packs then we should modify the mtime of later ones
+			 * to preserve this property.
+			 */
+			if (stat(tmpname, &st) < 0) {
+				warning("failed to stat %s: %s",
+					tmpname, strerror(errno));
+			} else if (!last_mtime) {
+				last_mtime = st.st_mtime;
+			} else {
+				struct utimbuf utb;
+				utb.actime = st.st_atime;
+				utb.modtime = --last_mtime;
+				if (utime(tmpname, &utb) < 0)
+					warning("failed utime() on %s: %s",
+						tmpname, strerror(errno));
+			}
+
+			snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
+				 base_name, sha1_to_hex(sha1));
+			if (adjust_shared_perm(idx_tmp_name))
+				die_errno("unable to make temporary index file readable");
+			if (rename(idx_tmp_name, tmpname))
+				die_errno("unable to rename temporary index file");
+
+			free((void *) idx_tmp_name);
+			free(pack_tmp_name);
+			puts(sha1_to_hex(sha1));
+		}
+
+		/* mark written objects as written to previous pack */
+		for (j = 0; j < nr_written; j++) {
+			written_list[j]->offset = (off_t)-1;
+		}
+		nr_remaining -= nr_written;
+	} while (nr_remaining && i < nr_objects);
+
+	free(written_list);
+	stop_progress(&progress_state);
+	if (written != nr_result)
+		die("wrote %"PRIu32" objects while expecting %"PRIu32,
+			written, nr_result);
+}
+
+static int locate_object_entry_hash(const unsigned char *sha1)
+{
+	int i;
+	unsigned int ui;
+	memcpy(&ui, sha1, sizeof(unsigned int));
+	i = ui % object_ix_hashsz;
+	while (0 < object_ix[i]) {
+		if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
+			return i;
+		if (++i == object_ix_hashsz)
+			i = 0;
+	}
+	return -1 - i;
+}
+
+static struct object_entry *locate_object_entry(const unsigned char *sha1)
+{
+	int i;
+
+	if (!object_ix_hashsz)
+		return NULL;
+
+	i = locate_object_entry_hash(sha1);
+	if (0 <= i)
+		return &objects[object_ix[i]-1];
+	return NULL;
+}
+
+static void rehash_objects(void)
+{
+	uint32_t i;
+	struct object_entry *oe;
+
+	object_ix_hashsz = nr_objects * 3;
+	if (object_ix_hashsz < 1024)
+		object_ix_hashsz = 1024;
+	object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
+	memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
+	for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
+		int ix = locate_object_entry_hash(oe->idx.sha1);
+		if (0 <= ix)
+			continue;
+		ix = -1 - ix;
+		object_ix[ix] = i + 1;
+	}
+}
+
+static unsigned name_hash(const char *name)
+{
+	unsigned c, hash = 0;
+
+	if (!name)
+		return 0;
+
+	/*
+	 * This effectively just creates a sortable number from the
+	 * last sixteen non-whitespace characters. Last characters
+	 * count "most", so things that end in ".c" sort together.
+	 */
+	while ((c = *name++) != 0) {
+		if (isspace(c))
+			continue;
+		hash = (hash >> 2) + (c << 24);
+	}
+	return hash;
+}
+
+static void setup_delta_attr_check(struct git_attr_check *check)
+{
+	static struct git_attr *attr_delta;
+
+	if (!attr_delta)
+		attr_delta = git_attr("delta");
+
+	check[0].attr = attr_delta;
+}
+
+static int no_try_delta(const char *path)
+{
+	struct git_attr_check check[1];
+
+	setup_delta_attr_check(check);
+	if (git_checkattr(path, ARRAY_SIZE(check), check))
+		return 0;
+	if (ATTR_FALSE(check->value))
+		return 1;
+	return 0;
+}
+
+static int add_object_entry(const unsigned char *sha1, enum object_type type,
+			    const char *name, int exclude)
+{
+	struct object_entry *entry;
+	struct packed_git *p, *found_pack = NULL;
+	off_t found_offset = 0;
+	int ix;
+	unsigned hash = name_hash(name);
+
+	ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
+	if (ix >= 0) {
+		if (exclude) {
+			entry = objects + object_ix[ix] - 1;
+			if (!entry->preferred_base)
+				nr_result--;
+			entry->preferred_base = 1;
+		}
+		return 0;
+	}
+
+	if (!exclude && local && has_loose_object_nonlocal(sha1))
+		return 0;
+
+	for (p = packed_git; p; p = p->next) {
+		off_t offset = find_pack_entry_one(sha1, p);
+		if (offset) {
+			if (!found_pack) {
+				found_offset = offset;
+				found_pack = p;
+			}
+			if (exclude)
+				break;
+			if (incremental)
+				return 0;
+			if (local && !p->pack_local)
+				return 0;
+			if (ignore_packed_keep && p->pack_local && p->pack_keep)
+				return 0;
+		}
+	}
+
+	if (nr_objects >= nr_alloc) {
+		nr_alloc = (nr_alloc  + 1024) * 3 / 2;
+		objects = xrealloc(objects, nr_alloc * sizeof(*entry));
+	}
+
+	entry = objects + nr_objects++;
+	memset(entry, 0, sizeof(*entry));
+	hashcpy(entry->idx.sha1, sha1);
+	entry->hash = hash;
+	if (type)
+		entry->type = type;
+	if (exclude)
+		entry->preferred_base = 1;
+	else
+		nr_result++;
+	if (found_pack) {
+		entry->in_pack = found_pack;
+		entry->in_pack_offset = found_offset;
+	}
+
+	if (object_ix_hashsz * 3 <= nr_objects * 4)
+		rehash_objects();
+	else
+		object_ix[-1 - ix] = nr_objects;
+
+	display_progress(progress_state, nr_objects);
+
+	if (name && no_try_delta(name))
+		entry->no_try_delta = 1;
+
+	return 1;
+}
+
+struct pbase_tree_cache {
+	unsigned char sha1[20];
+	int ref;
+	int temporary;
+	void *tree_data;
+	unsigned long tree_size;
+};
+
+static struct pbase_tree_cache *(pbase_tree_cache[256]);
+static int pbase_tree_cache_ix(const unsigned char *sha1)
+{
+	return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
+}
+static int pbase_tree_cache_ix_incr(int ix)
+{
+	return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
+}
+
+static struct pbase_tree {
+	struct pbase_tree *next;
+	/* This is a phony "cache" entry; we are not
+	 * going to evict it nor find it through _get()
+	 * mechanism -- this is for the toplevel node that
+	 * would almost always change with any commit.
+	 */
+	struct pbase_tree_cache pcache;
+} *pbase_tree;
+
+static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
+{
+	struct pbase_tree_cache *ent, *nent;
+	void *data;
+	unsigned long size;
+	enum object_type type;
+	int neigh;
+	int my_ix = pbase_tree_cache_ix(sha1);
+	int available_ix = -1;
+
+	/* pbase-tree-cache acts as a limited hashtable.
+	 * your object will be found at your index or within a few
+	 * slots after that slot if it is cached.
+	 */
+	for (neigh = 0; neigh < 8; neigh++) {
+		ent = pbase_tree_cache[my_ix];
+		if (ent && !hashcmp(ent->sha1, sha1)) {
+			ent->ref++;
+			return ent;
+		}
+		else if (((available_ix < 0) && (!ent || !ent->ref)) ||
+			 ((0 <= available_ix) &&
+			  (!ent && pbase_tree_cache[available_ix])))
+			available_ix = my_ix;
+		if (!ent)
+			break;
+		my_ix = pbase_tree_cache_ix_incr(my_ix);
+	}
+
+	/* Did not find one.  Either we got a bogus request or
+	 * we need to read and perhaps cache.
+	 */
+	data = read_sha1_file(sha1, &type, &size);
+	if (!data)
+		return NULL;
+	if (type != OBJ_TREE) {
+		free(data);
+		return NULL;
+	}
+
+	/* We need to either cache or return a throwaway copy */
+
+	if (available_ix < 0)
+		ent = NULL;
+	else {
+		ent = pbase_tree_cache[available_ix];
+		my_ix = available_ix;
+	}
+
+	if (!ent) {
+		nent = xmalloc(sizeof(*nent));
+		nent->temporary = (available_ix < 0);
+	}
+	else {
+		/* evict and reuse */
+		free(ent->tree_data);
+		nent = ent;
+	}
+	hashcpy(nent->sha1, sha1);
+	nent->tree_data = data;
+	nent->tree_size = size;
+	nent->ref = 1;
+	if (!nent->temporary)
+		pbase_tree_cache[my_ix] = nent;
+	return nent;
+}
+
+static void pbase_tree_put(struct pbase_tree_cache *cache)
+{
+	if (!cache->temporary) {
+		cache->ref--;
+		return;
+	}
+	free(cache->tree_data);
+	free(cache);
+}
+
+static int name_cmp_len(const char *name)
+{
+	int i;
+	for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
+		;
+	return i;
+}
+
+static void add_pbase_object(struct tree_desc *tree,
+			     const char *name,
+			     int cmplen,
+			     const char *fullname)
+{
+	struct name_entry entry;
+	int cmp;
+
+	while (tree_entry(tree,&entry)) {
+		if (S_ISGITLINK(entry.mode))
+			continue;
+		cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
+		      memcmp(name, entry.path, cmplen);
+		if (cmp > 0)
+			continue;
+		if (cmp < 0)
+			return;
+		if (name[cmplen] != '/') {
+			add_object_entry(entry.sha1,
+					 object_type(entry.mode),
+					 fullname, 1);
+			return;
+		}
+		if (S_ISDIR(entry.mode)) {
+			struct tree_desc sub;
+			struct pbase_tree_cache *tree;
+			const char *down = name+cmplen+1;
+			int downlen = name_cmp_len(down);
+
+			tree = pbase_tree_get(entry.sha1);
+			if (!tree)
+				return;
+			init_tree_desc(&sub, tree->tree_data, tree->tree_size);
+
+			add_pbase_object(&sub, down, downlen, fullname);
+			pbase_tree_put(tree);
+		}
+	}
+}
+
+static unsigned *done_pbase_paths;
+static int done_pbase_paths_num;
+static int done_pbase_paths_alloc;
+static int done_pbase_path_pos(unsigned hash)
+{
+	int lo = 0;
+	int hi = done_pbase_paths_num;
+	while (lo < hi) {
+		int mi = (hi + lo) / 2;
+		if (done_pbase_paths[mi] == hash)
+			return mi;
+		if (done_pbase_paths[mi] < hash)
+			hi = mi;
+		else
+			lo = mi + 1;
+	}
+	return -lo-1;
+}
+
+static int check_pbase_path(unsigned hash)
+{
+	int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
+	if (0 <= pos)
+		return 1;
+	pos = -pos - 1;
+	if (done_pbase_paths_alloc <= done_pbase_paths_num) {
+		done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
+		done_pbase_paths = xrealloc(done_pbase_paths,
+					    done_pbase_paths_alloc *
+					    sizeof(unsigned));
+	}
+	done_pbase_paths_num++;
+	if (pos < done_pbase_paths_num)
+		memmove(done_pbase_paths + pos + 1,
+			done_pbase_paths + pos,
+			(done_pbase_paths_num - pos - 1) * sizeof(unsigned));
+	done_pbase_paths[pos] = hash;
+	return 0;
+}
+
+static void add_preferred_base_object(const char *name)
+{
+	struct pbase_tree *it;
+	int cmplen;
+	unsigned hash = name_hash(name);
+
+	if (!num_preferred_base || check_pbase_path(hash))
+		return;
+
+	cmplen = name_cmp_len(name);
+	for (it = pbase_tree; it; it = it->next) {
+		if (cmplen == 0) {
+			add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
+		}
+		else {
+			struct tree_desc tree;
+			init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
+			add_pbase_object(&tree, name, cmplen, name);
+		}
+	}
+}
+
+static void add_preferred_base(unsigned char *sha1)
+{
+	struct pbase_tree *it;
+	void *data;
+	unsigned long size;
+	unsigned char tree_sha1[20];
+
+	if (window <= num_preferred_base++)
+		return;
+
+	data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
+	if (!data)
+		return;
+
+	for (it = pbase_tree; it; it = it->next) {
+		if (!hashcmp(it->pcache.sha1, tree_sha1)) {
+			free(data);
+			return;
+		}
+	}
+
+	it = xcalloc(1, sizeof(*it));
+	it->next = pbase_tree;
+	pbase_tree = it;
+
+	hashcpy(it->pcache.sha1, tree_sha1);
+	it->pcache.tree_data = data;
+	it->pcache.tree_size = size;
+}
+
+static void cleanup_preferred_base(void)
+{
+	struct pbase_tree *it;
+	unsigned i;
+
+	it = pbase_tree;
+	pbase_tree = NULL;
+	while (it) {
+		struct pbase_tree *this = it;
+		it = this->next;
+		free(this->pcache.tree_data);
+		free(this);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(pbase_tree_cache); i++) {
+		if (!pbase_tree_cache[i])
+			continue;
+		free(pbase_tree_cache[i]->tree_data);
+		free(pbase_tree_cache[i]);
+		pbase_tree_cache[i] = NULL;
+	}
+
+	free(done_pbase_paths);
+	done_pbase_paths = NULL;
+	done_pbase_paths_num = done_pbase_paths_alloc = 0;
+}
+
+static void check_object(struct object_entry *entry)
+{
+	if (entry->in_pack) {
+		struct packed_git *p = entry->in_pack;
+		struct pack_window *w_curs = NULL;
+		const unsigned char *base_ref = NULL;
+		struct object_entry *base_entry;
+		unsigned long used, used_0;
+		unsigned int avail;
+		off_t ofs;
+		unsigned char *buf, c;
+
+		buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
+
+		/*
+		 * We want in_pack_type even if we do not reuse delta
+		 * since non-delta representations could still be reused.
+		 */
+		used = unpack_object_header_buffer(buf, avail,
+						   &entry->in_pack_type,
+						   &entry->size);
+		if (used == 0)
+			goto give_up;
+
+		/*
+		 * Determine if this is a delta and if so whether we can
+		 * reuse it or not.  Otherwise let's find out as cheaply as
+		 * possible what the actual type and size for this object is.
+		 */
+		switch (entry->in_pack_type) {
+		default:
+			/* Not a delta hence we've already got all we need. */
+			entry->type = entry->in_pack_type;
+			entry->in_pack_header_size = used;
+			if (entry->type < OBJ_COMMIT || entry->type > OBJ_BLOB)
+				goto give_up;
+			unuse_pack(&w_curs);
+			return;
+		case OBJ_REF_DELTA:
+			if (reuse_delta && !entry->preferred_base)
+				base_ref = use_pack(p, &w_curs,
+						entry->in_pack_offset + used, NULL);
+			entry->in_pack_header_size = used + 20;
+			break;
+		case OBJ_OFS_DELTA:
+			buf = use_pack(p, &w_curs,
+				       entry->in_pack_offset + used, NULL);
+			used_0 = 0;
+			c = buf[used_0++];
+			ofs = c & 127;
+			while (c & 128) {
+				ofs += 1;
+				if (!ofs || MSB(ofs, 7)) {
+					error("delta base offset overflow in pack for %s",
+					      sha1_to_hex(entry->idx.sha1));
+					goto give_up;
+				}
+				c = buf[used_0++];
+				ofs = (ofs << 7) + (c & 127);
+			}
+			ofs = entry->in_pack_offset - ofs;
+			if (ofs <= 0 || ofs >= entry->in_pack_offset) {
+				error("delta base offset out of bound for %s",
+				      sha1_to_hex(entry->idx.sha1));
+				goto give_up;
+			}
+			if (reuse_delta && !entry->preferred_base) {
+				struct revindex_entry *revidx;
+				revidx = find_pack_revindex(p, ofs);
+				if (!revidx)
+					goto give_up;
+				base_ref = nth_packed_object_sha1(p, revidx->nr);
+			}
+			entry->in_pack_header_size = used + used_0;
+			break;
+		}
+
+		if (base_ref && (base_entry = locate_object_entry(base_ref))) {
+			/*
+			 * If base_ref was set above that means we wish to
+			 * reuse delta data, and we even found that base
+			 * in the list of objects we want to pack. Goodie!
+			 *
+			 * Depth value does not matter - find_deltas() will
+			 * never consider reused delta as the base object to
+			 * deltify other objects against, in order to avoid
+			 * circular deltas.
+			 */
+			entry->type = entry->in_pack_type;
+			entry->delta = base_entry;
+			entry->delta_size = entry->size;
+			entry->delta_sibling = base_entry->delta_child;
+			base_entry->delta_child = entry;
+			unuse_pack(&w_curs);
+			return;
+		}
+
+		if (entry->type) {
+			/*
+			 * This must be a delta and we already know what the
+			 * final object type is.  Let's extract the actual
+			 * object size from the delta header.
+			 */
+			entry->size = get_size_from_delta(p, &w_curs,
+					entry->in_pack_offset + entry->in_pack_header_size);
+			if (entry->size == 0)
+				goto give_up;
+			unuse_pack(&w_curs);
+			return;
+		}
+
+		/*
+		 * No choice but to fall back to the recursive delta walk
+		 * with sha1_object_info() to find about the object type
+		 * at this point...
+		 */
+		give_up:
+		unuse_pack(&w_curs);
+	}
+
+	entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
+	/*
+	 * The error condition is checked in prepare_pack().  This is
+	 * to permit a missing preferred base object to be ignored
+	 * as a preferred base.  Doing so can result in a larger
+	 * pack file, but the transfer will still take place.
+	 */
+}
+
+static int pack_offset_sort(const void *_a, const void *_b)
+{
+	const struct object_entry *a = *(struct object_entry **)_a;
+	const struct object_entry *b = *(struct object_entry **)_b;
+
+	/* avoid filesystem trashing with loose objects */
+	if (!a->in_pack && !b->in_pack)
+		return hashcmp(a->idx.sha1, b->idx.sha1);
+
+	if (a->in_pack < b->in_pack)
+		return -1;
+	if (a->in_pack > b->in_pack)
+		return 1;
+	return a->in_pack_offset < b->in_pack_offset ? -1 :
+			(a->in_pack_offset > b->in_pack_offset);
+}
+
+static void get_object_details(void)
+{
+	uint32_t i;
+	struct object_entry **sorted_by_offset;
+
+	sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
+	for (i = 0; i < nr_objects; i++)
+		sorted_by_offset[i] = objects + i;
+	qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
+
+	for (i = 0; i < nr_objects; i++)
+		check_object(sorted_by_offset[i]);
+
+	free(sorted_by_offset);
+}
+
+/*
+ * We search for deltas in a list sorted by type, by filename hash, and then
+ * by size, so that we see progressively smaller and smaller files.
+ * That's because we prefer deltas to be from the bigger file
+ * to the smaller -- deletes are potentially cheaper, but perhaps
+ * more importantly, the bigger file is likely the more recent
+ * one.  The deepest deltas are therefore the oldest objects which are
+ * less susceptible to be accessed often.
+ */
+static int type_size_sort(const void *_a, const void *_b)
+{
+	const struct object_entry *a = *(struct object_entry **)_a;
+	const struct object_entry *b = *(struct object_entry **)_b;
+
+	if (a->type > b->type)
+		return -1;
+	if (a->type < b->type)
+		return 1;
+	if (a->hash > b->hash)
+		return -1;
+	if (a->hash < b->hash)
+		return 1;
+	if (a->preferred_base > b->preferred_base)
+		return -1;
+	if (a->preferred_base < b->preferred_base)
+		return 1;
+	if (a->size > b->size)
+		return -1;
+	if (a->size < b->size)
+		return 1;
+	return a < b ? -1 : (a > b);  /* newest first */
+}
+
+struct unpacked {
+	struct object_entry *entry;
+	void *data;
+	struct delta_index *index;
+	unsigned depth;
+};
+
+static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
+			   unsigned long delta_size)
+{
+	if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
+		return 0;
+
+	if (delta_size < cache_max_small_delta_size)
+		return 1;
+
+	/* cache delta, if objects are large enough compared to delta size */
+	if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
+		return 1;
+
+	return 0;
+}
+
+#ifndef NO_PTHREADS
+
+static pthread_mutex_t read_mutex;
+#define read_lock()		pthread_mutex_lock(&read_mutex)
+#define read_unlock()		pthread_mutex_unlock(&read_mutex)
+
+static pthread_mutex_t cache_mutex;
+#define cache_lock()		pthread_mutex_lock(&cache_mutex)
+#define cache_unlock()		pthread_mutex_unlock(&cache_mutex)
+
+static pthread_mutex_t progress_mutex;
+#define progress_lock()		pthread_mutex_lock(&progress_mutex)
+#define progress_unlock()	pthread_mutex_unlock(&progress_mutex)
+
+#else
+
+#define read_lock()		(void)0
+#define read_unlock()		(void)0
+#define cache_lock()		(void)0
+#define cache_unlock()		(void)0
+#define progress_lock()		(void)0
+#define progress_unlock()	(void)0
+
+#endif
+
+static int try_delta(struct unpacked *trg, struct unpacked *src,
+		     unsigned max_depth, unsigned long *mem_usage)
+{
+	struct object_entry *trg_entry = trg->entry;
+	struct object_entry *src_entry = src->entry;
+	unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
+	unsigned ref_depth;
+	enum object_type type;
+	void *delta_buf;
+
+	/* Don't bother doing diffs between different types */
+	if (trg_entry->type != src_entry->type)
+		return -1;
+
+	/*
+	 * We do not bother to try a delta that we discarded
+	 * on an earlier try, but only when reusing delta data.
+	 */
+	if (reuse_delta && trg_entry->in_pack &&
+	    trg_entry->in_pack == src_entry->in_pack &&
+	    trg_entry->in_pack_type != OBJ_REF_DELTA &&
+	    trg_entry->in_pack_type != OBJ_OFS_DELTA)
+		return 0;
+
+	/* Let's not bust the allowed depth. */
+	if (src->depth >= max_depth)
+		return 0;
+
+	/* Now some size filtering heuristics. */
+	trg_size = trg_entry->size;
+	if (!trg_entry->delta) {
+		max_size = trg_size/2 - 20;
+		ref_depth = 1;
+	} else {
+		max_size = trg_entry->delta_size;
+		ref_depth = trg->depth;
+	}
+	max_size = (uint64_t)max_size * (max_depth - src->depth) /
+						(max_depth - ref_depth + 1);
+	if (max_size == 0)
+		return 0;
+	src_size = src_entry->size;
+	sizediff = src_size < trg_size ? trg_size - src_size : 0;
+	if (sizediff >= max_size)
+		return 0;
+	if (trg_size < src_size / 32)
+		return 0;
+
+	/* Load data if not already done */
+	if (!trg->data) {
+		read_lock();
+		trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
+		read_unlock();
+		if (!trg->data)
+			die("object %s cannot be read",
+			    sha1_to_hex(trg_entry->idx.sha1));
+		if (sz != trg_size)
+			die("object %s inconsistent object length (%lu vs %lu)",
+			    sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
+		*mem_usage += sz;
+	}
+	if (!src->data) {
+		read_lock();
+		src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
+		read_unlock();
+		if (!src->data)
+			die("object %s cannot be read",
+			    sha1_to_hex(src_entry->idx.sha1));
+		if (sz != src_size)
+			die("object %s inconsistent object length (%lu vs %lu)",
+			    sha1_to_hex(src_entry->idx.sha1), sz, src_size);
+		*mem_usage += sz;
+	}
+	if (!src->index) {
+		src->index = create_delta_index(src->data, src_size);
+		if (!src->index) {
+			static int warned = 0;
+			if (!warned++)
+				warning("suboptimal pack - out of memory");
+			return 0;
+		}
+		*mem_usage += sizeof_delta_index(src->index);
+	}
+
+	delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
+	if (!delta_buf)
+		return 0;
+
+	if (trg_entry->delta) {
+		/* Prefer only shallower same-sized deltas. */
+		if (delta_size == trg_entry->delta_size &&
+		    src->depth + 1 >= trg->depth) {
+			free(delta_buf);
+			return 0;
+		}
+	}
+
+	/*
+	 * Handle memory allocation outside of the cache
+	 * accounting lock.  Compiler will optimize the strangeness
+	 * away when NO_PTHREADS is defined.
+	 */
+	free(trg_entry->delta_data);
+	cache_lock();
+	if (trg_entry->delta_data) {
+		delta_cache_size -= trg_entry->delta_size;
+		trg_entry->delta_data = NULL;
+	}
+	if (delta_cacheable(src_size, trg_size, delta_size)) {
+		delta_cache_size += delta_size;
+		cache_unlock();
+		trg_entry->delta_data = xrealloc(delta_buf, delta_size);
+	} else {
+		cache_unlock();
+		free(delta_buf);
+	}
+
+	trg_entry->delta = src_entry;
+	trg_entry->delta_size = delta_size;
+	trg->depth = src->depth + 1;
+
+	return 1;
+}
+
+static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
+{
+	struct object_entry *child = me->delta_child;
+	unsigned int m = n;
+	while (child) {
+		unsigned int c = check_delta_limit(child, n + 1);
+		if (m < c)
+			m = c;
+		child = child->delta_sibling;
+	}
+	return m;
+}
+
+static unsigned long free_unpacked(struct unpacked *n)
+{
+	unsigned long freed_mem = sizeof_delta_index(n->index);
+	free_delta_index(n->index);
+	n->index = NULL;
+	if (n->data) {
+		freed_mem += n->entry->size;
+		free(n->data);
+		n->data = NULL;
+	}
+	n->entry = NULL;
+	n->depth = 0;
+	return freed_mem;
+}
+
+static void find_deltas(struct object_entry **list, unsigned *list_size,
+			int window, int depth, unsigned *processed)
+{
+	uint32_t i, idx = 0, count = 0;
+	struct unpacked *array;
+	unsigned long mem_usage = 0;
+
+	array = xcalloc(window, sizeof(struct unpacked));
+
+	for (;;) {
+		struct object_entry *entry;
+		struct unpacked *n = array + idx;
+		int j, max_depth, best_base = -1;
+
+		progress_lock();
+		if (!*list_size) {
+			progress_unlock();
+			break;
+		}
+		entry = *list++;
+		(*list_size)--;
+		if (!entry->preferred_base) {
+			(*processed)++;
+			display_progress(progress_state, *processed);
+		}
+		progress_unlock();
+
+		mem_usage -= free_unpacked(n);
+		n->entry = entry;
+
+		while (window_memory_limit &&
+		       mem_usage > window_memory_limit &&
+		       count > 1) {
+			uint32_t tail = (idx + window - count) % window;
+			mem_usage -= free_unpacked(array + tail);
+			count--;
+		}
+
+		/* We do not compute delta to *create* objects we are not
+		 * going to pack.
+		 */
+		if (entry->preferred_base)
+			goto next;
+
+		/*
+		 * If the current object is at pack edge, take the depth the
+		 * objects that depend on the current object into account
+		 * otherwise they would become too deep.
+		 */
+		max_depth = depth;
+		if (entry->delta_child) {
+			max_depth -= check_delta_limit(entry, 0);
+			if (max_depth <= 0)
+				goto next;
+		}
+
+		j = window;
+		while (--j > 0) {
+			int ret;
+			uint32_t other_idx = idx + j;
+			struct unpacked *m;
+			if (other_idx >= window)
+				other_idx -= window;
+			m = array + other_idx;
+			if (!m->entry)
+				break;
+			ret = try_delta(n, m, max_depth, &mem_usage);
+			if (ret < 0)
+				break;
+			else if (ret > 0)
+				best_base = other_idx;
+		}
+
+		/*
+		 * If we decided to cache the delta data, then it is best
+		 * to compress it right away.  First because we have to do
+		 * it anyway, and doing it here while we're threaded will
+		 * save a lot of time in the non threaded write phase,
+		 * as well as allow for caching more deltas within
+		 * the same cache size limit.
+		 * ...
+		 * But only if not writing to stdout, since in that case
+		 * the network is most likely throttling writes anyway,
+		 * and therefore it is best to go to the write phase ASAP
+		 * instead, as we can afford spending more time compressing
+		 * between writes at that moment.
+		 */
+		if (entry->delta_data && !pack_to_stdout) {
+			entry->z_delta_size = do_compress(&entry->delta_data,
+							  entry->delta_size);
+			cache_lock();
+			delta_cache_size -= entry->delta_size;
+			delta_cache_size += entry->z_delta_size;
+			cache_unlock();
+		}
+
+		/* if we made n a delta, and if n is already at max
+		 * depth, leaving it in the window is pointless.  we
+		 * should evict it first.
+		 */
+		if (entry->delta && max_depth <= n->depth)
+			continue;
+
+		/*
+		 * Move the best delta base up in the window, after the
+		 * currently deltified object, to keep it longer.  It will
+		 * be the first base object to be attempted next.
+		 */
+		if (entry->delta) {
+			struct unpacked swap = array[best_base];
+			int dist = (window + idx - best_base) % window;
+			int dst = best_base;
+			while (dist--) {
+				int src = (dst + 1) % window;
+				array[dst] = array[src];
+				dst = src;
+			}
+			array[dst] = swap;
+		}
+
+		next:
+		idx++;
+		if (count + 1 < window)
+			count++;
+		if (idx >= window)
+			idx = 0;
+	}
+
+	for (i = 0; i < window; ++i) {
+		free_delta_index(array[i].index);
+		free(array[i].data);
+	}
+	free(array);
+}
+
+#ifndef NO_PTHREADS
+
+/*
+ * The main thread waits on the condition that (at least) one of the workers
+ * has stopped working (which is indicated in the .working member of
+ * struct thread_params).
+ * When a work thread has completed its work, it sets .working to 0 and
+ * signals the main thread and waits on the condition that .data_ready
+ * becomes 1.
+ */
+
+struct thread_params {
+	pthread_t thread;
+	struct object_entry **list;
+	unsigned list_size;
+	unsigned remaining;
+	int window;
+	int depth;
+	int working;
+	int data_ready;
+	pthread_mutex_t mutex;
+	pthread_cond_t cond;
+	unsigned *processed;
+};
+
+static pthread_cond_t progress_cond;
+
+/*
+ * Mutex and conditional variable can't be statically-initialized on Windows.
+ */
+static void init_threaded_search(void)
+{
+	pthread_mutex_init(&read_mutex, NULL);
+	pthread_mutex_init(&cache_mutex, NULL);
+	pthread_mutex_init(&progress_mutex, NULL);
+	pthread_cond_init(&progress_cond, NULL);
+}
+
+static void cleanup_threaded_search(void)
+{
+	pthread_cond_destroy(&progress_cond);
+	pthread_mutex_destroy(&read_mutex);
+	pthread_mutex_destroy(&cache_mutex);
+	pthread_mutex_destroy(&progress_mutex);
+}
+
+static void *threaded_find_deltas(void *arg)
+{
+	struct thread_params *me = arg;
+
+	while (me->remaining) {
+		find_deltas(me->list, &me->remaining,
+			    me->window, me->depth, me->processed);
+
+		progress_lock();
+		me->working = 0;
+		pthread_cond_signal(&progress_cond);
+		progress_unlock();
+
+		/*
+		 * We must not set ->data_ready before we wait on the
+		 * condition because the main thread may have set it to 1
+		 * before we get here. In order to be sure that new
+		 * work is available if we see 1 in ->data_ready, it
+		 * was initialized to 0 before this thread was spawned
+		 * and we reset it to 0 right away.
+		 */
+		pthread_mutex_lock(&me->mutex);
+		while (!me->data_ready)
+			pthread_cond_wait(&me->cond, &me->mutex);
+		me->data_ready = 0;
+		pthread_mutex_unlock(&me->mutex);
+	}
+	/* leave ->working 1 so that this doesn't get more work assigned */
+	return NULL;
+}
+
+static void ll_find_deltas(struct object_entry **list, unsigned list_size,
+			   int window, int depth, unsigned *processed)
+{
+	struct thread_params *p;
+	int i, ret, active_threads = 0;
+
+	init_threaded_search();
+
+	if (!delta_search_threads)	/* --threads=0 means autodetect */
+		delta_search_threads = online_cpus();
+	if (delta_search_threads <= 1) {
+		find_deltas(list, &list_size, window, depth, processed);
+		cleanup_threaded_search();
+		return;
+	}
+	if (progress > pack_to_stdout)
+		fprintf(stderr, "Delta compression using up to %d threads.\n",
+				delta_search_threads);
+	p = xcalloc(delta_search_threads, sizeof(*p));
+
+	/* Partition the work amongst work threads. */
+	for (i = 0; i < delta_search_threads; i++) {
+		unsigned sub_size = list_size / (delta_search_threads - i);
+
+		/* don't use too small segments or no deltas will be found */
+		if (sub_size < 2*window && i+1 < delta_search_threads)
+			sub_size = 0;
+
+		p[i].window = window;
+		p[i].depth = depth;
+		p[i].processed = processed;
+		p[i].working = 1;
+		p[i].data_ready = 0;
+
+		/* try to split chunks on "path" boundaries */
+		while (sub_size && sub_size < list_size &&
+		       list[sub_size]->hash &&
+		       list[sub_size]->hash == list[sub_size-1]->hash)
+			sub_size++;
+
+		p[i].list = list;
+		p[i].list_size = sub_size;
+		p[i].remaining = sub_size;
+
+		list += sub_size;
+		list_size -= sub_size;
+	}
+
+	/* Start work threads. */
+	for (i = 0; i < delta_search_threads; i++) {
+		if (!p[i].list_size)
+			continue;
+		pthread_mutex_init(&p[i].mutex, NULL);
+		pthread_cond_init(&p[i].cond, NULL);
+		ret = pthread_create(&p[i].thread, NULL,
+				     threaded_find_deltas, &p[i]);
+		if (ret)
+			die("unable to create thread: %s", strerror(ret));
+		active_threads++;
+	}
+
+	/*
+	 * Now let's wait for work completion.  Each time a thread is done
+	 * with its work, we steal half of the remaining work from the
+	 * thread with the largest number of unprocessed objects and give
+	 * it to that newly idle thread.  This ensure good load balancing
+	 * until the remaining object list segments are simply too short
+	 * to be worth splitting anymore.
+	 */
+	while (active_threads) {
+		struct thread_params *target = NULL;
+		struct thread_params *victim = NULL;
+		unsigned sub_size = 0;
+
+		progress_lock();
+		for (;;) {
+			for (i = 0; !target && i < delta_search_threads; i++)
+				if (!p[i].working)
+					target = &p[i];
+			if (target)
+				break;
+			pthread_cond_wait(&progress_cond, &progress_mutex);
+		}
+
+		for (i = 0; i < delta_search_threads; i++)
+			if (p[i].remaining > 2*window &&
+			    (!victim || victim->remaining < p[i].remaining))
+				victim = &p[i];
+		if (victim) {
+			sub_size = victim->remaining / 2;
+			list = victim->list + victim->list_size - sub_size;
+			while (sub_size && list[0]->hash &&
+			       list[0]->hash == list[-1]->hash) {
+				list++;
+				sub_size--;
+			}
+			if (!sub_size) {
+				/*
+				 * It is possible for some "paths" to have
+				 * so many objects that no hash boundary
+				 * might be found.  Let's just steal the
+				 * exact half in that case.
+				 */
+				sub_size = victim->remaining / 2;
+				list -= sub_size;
+			}
+			target->list = list;
+			victim->list_size -= sub_size;
+			victim->remaining -= sub_size;
+		}
+		target->list_size = sub_size;
+		target->remaining = sub_size;
+		target->working = 1;
+		progress_unlock();
+
+		pthread_mutex_lock(&target->mutex);
+		target->data_ready = 1;
+		pthread_cond_signal(&target->cond);
+		pthread_mutex_unlock(&target->mutex);
+
+		if (!sub_size) {
+			pthread_join(target->thread, NULL);
+			pthread_cond_destroy(&target->cond);
+			pthread_mutex_destroy(&target->mutex);
+			active_threads--;
+		}
+	}
+	cleanup_threaded_search();
+	free(p);
+}
+
+#else
+#define ll_find_deltas(l, s, w, d, p)	find_deltas(l, &s, w, d, p)
+#endif
+
+static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+	unsigned char peeled[20];
+
+	if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
+	    !peel_ref(path, peeled)        && /* peelable? */
+	    !is_null_sha1(peeled)          && /* annotated tag? */
+	    locate_object_entry(peeled))      /* object packed? */
+		add_object_entry(sha1, OBJ_TAG, NULL, 0);
+	return 0;
+}
+
+static void prepare_pack(int window, int depth)
+{
+	struct object_entry **delta_list;
+	uint32_t i, nr_deltas;
+	unsigned n;
+
+	get_object_details();
+
+	/*
+	 * If we're locally repacking then we need to be doubly careful
+	 * from now on in order to make sure no stealth corruption gets
+	 * propagated to the new pack.  Clients receiving streamed packs
+	 * should validate everything they get anyway so no need to incur
+	 * the additional cost here in that case.
+	 */
+	if (!pack_to_stdout)
+		do_check_packed_object_crc = 1;
+
+	if (!nr_objects || !window || !depth)
+		return;
+
+	delta_list = xmalloc(nr_objects * sizeof(*delta_list));
+	nr_deltas = n = 0;
+
+	for (i = 0; i < nr_objects; i++) {
+		struct object_entry *entry = objects + i;
+
+		if (entry->delta)
+			/* This happens if we decided to reuse existing
+			 * delta from a pack.  "reuse_delta &&" is implied.
+			 */
+			continue;
+
+		if (entry->size < 50)
+			continue;
+
+		if (entry->no_try_delta)
+			continue;
+
+		if (!entry->preferred_base) {
+			nr_deltas++;
+			if (entry->type < 0)
+				die("unable to get type of object %s",
+				    sha1_to_hex(entry->idx.sha1));
+		} else {
+			if (entry->type < 0) {
+				/*
+				 * This object is not found, but we
+				 * don't have to include it anyway.
+				 */
+				continue;
+			}
+		}
+
+		delta_list[n++] = entry;
+	}
+
+	if (nr_deltas && n > 1) {
+		unsigned nr_done = 0;
+		if (progress)
+			progress_state = start_progress("Compressing objects",
+							nr_deltas);
+		qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
+		ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
+		stop_progress(&progress_state);
+		if (nr_done != nr_deltas)
+			die("inconsistency with delta count");
+	}
+	free(delta_list);
+}
+
+static int git_pack_config(const char *k, const char *v, void *cb)
+{
+	if (!strcmp(k, "pack.window")) {
+		window = git_config_int(k, v);
+		return 0;
+	}
+	if (!strcmp(k, "pack.windowmemory")) {
+		window_memory_limit = git_config_ulong(k, v);
+		return 0;
+	}
+	if (!strcmp(k, "pack.depth")) {
+		depth = git_config_int(k, v);
+		return 0;
+	}
+	if (!strcmp(k, "pack.compression")) {
+		int level = git_config_int(k, v);
+		if (level == -1)
+			level = Z_DEFAULT_COMPRESSION;
+		else if (level < 0 || level > Z_BEST_COMPRESSION)
+			die("bad pack compression level %d", level);
+		pack_compression_level = level;
+		pack_compression_seen = 1;
+		return 0;
+	}
+	if (!strcmp(k, "pack.deltacachesize")) {
+		max_delta_cache_size = git_config_int(k, v);
+		return 0;
+	}
+	if (!strcmp(k, "pack.deltacachelimit")) {
+		cache_max_small_delta_size = git_config_int(k, v);
+		return 0;
+	}
+	if (!strcmp(k, "pack.threads")) {
+		delta_search_threads = git_config_int(k, v);
+		if (delta_search_threads < 0)
+			die("invalid number of threads specified (%d)",
+			    delta_search_threads);
+#ifdef NO_PTHREADS
+		if (delta_search_threads != 1)
+			warning("no threads support, ignoring %s", k);
+#endif
+		return 0;
+	}
+	if (!strcmp(k, "pack.indexversion")) {
+		pack_idx_default_version = git_config_int(k, v);
+		if (pack_idx_default_version > 2)
+			die("bad pack.indexversion=%"PRIu32,
+				pack_idx_default_version);
+		return 0;
+	}
+	if (!strcmp(k, "pack.packsizelimit")) {
+		pack_size_limit_cfg = git_config_ulong(k, v);
+		return 0;
+	}
+	return git_default_config(k, v, cb);
+}
+
+static void read_object_list_from_stdin(void)
+{
+	char line[40 + 1 + PATH_MAX + 2];
+	unsigned char sha1[20];
+
+	for (;;) {
+		if (!fgets(line, sizeof(line), stdin)) {
+			if (feof(stdin))
+				break;
+			if (!ferror(stdin))
+				die("fgets returned NULL, not EOF, not error!");
+			if (errno != EINTR)
+				die_errno("fgets");
+			clearerr(stdin);
+			continue;
+		}
+		if (line[0] == '-') {
+			if (get_sha1_hex(line+1, sha1))
+				die("expected edge sha1, got garbage:\n %s",
+				    line);
+			add_preferred_base(sha1);
+			continue;
+		}
+		if (get_sha1_hex(line, sha1))
+			die("expected sha1, got garbage:\n %s", line);
+
+		add_preferred_base_object(line+41);
+		add_object_entry(sha1, 0, line+41, 0);
+	}
+}
+
+#define OBJECT_ADDED (1u<<20)
+
+static void show_commit(struct commit *commit, void *data)
+{
+	add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
+	commit->object.flags |= OBJECT_ADDED;
+}
+
+static void show_object(struct object *obj, const struct name_path *path, const char *last)
+{
+	char *name = path_name(path, last);
+
+	add_preferred_base_object(name);
+	add_object_entry(obj->sha1, obj->type, name, 0);
+	obj->flags |= OBJECT_ADDED;
+
+	/*
+	 * We will have generated the hash from the name,
+	 * but not saved a pointer to it - we can free it
+	 */
+	free((char *)name);
+}
+
+static void show_edge(struct commit *commit)
+{
+	add_preferred_base(commit->object.sha1);
+}
+
+struct in_pack_object {
+	off_t offset;
+	struct object *object;
+};
+
+struct in_pack {
+	int alloc;
+	int nr;
+	struct in_pack_object *array;
+};
+
+static void mark_in_pack_object(struct object *object, struct packed_git *p, struct in_pack *in_pack)
+{
+	in_pack->array[in_pack->nr].offset = find_pack_entry_one(object->sha1, p);
+	in_pack->array[in_pack->nr].object = object;
+	in_pack->nr++;
+}
+
+/*
+ * Compare the objects in the offset order, in order to emulate the
+ * "git rev-list --objects" output that produced the pack originally.
+ */
+static int ofscmp(const void *a_, const void *b_)
+{
+	struct in_pack_object *a = (struct in_pack_object *)a_;
+	struct in_pack_object *b = (struct in_pack_object *)b_;
+
+	if (a->offset < b->offset)
+		return -1;
+	else if (a->offset > b->offset)
+		return 1;
+	else
+		return hashcmp(a->object->sha1, b->object->sha1);
+}
+
+static void add_objects_in_unpacked_packs(struct rev_info *revs)
+{
+	struct packed_git *p;
+	struct in_pack in_pack;
+	uint32_t i;
+
+	memset(&in_pack, 0, sizeof(in_pack));
+
+	for (p = packed_git; p; p = p->next) {
+		const unsigned char *sha1;
+		struct object *o;
+
+		if (!p->pack_local || p->pack_keep)
+			continue;
+		if (open_pack_index(p))
+			die("cannot open pack index");
+
+		ALLOC_GROW(in_pack.array,
+			   in_pack.nr + p->num_objects,
+			   in_pack.alloc);
+
+		for (i = 0; i < p->num_objects; i++) {
+			sha1 = nth_packed_object_sha1(p, i);
+			o = lookup_unknown_object(sha1);
+			if (!(o->flags & OBJECT_ADDED))
+				mark_in_pack_object(o, p, &in_pack);
+			o->flags |= OBJECT_ADDED;
+		}
+	}
+
+	if (in_pack.nr) {
+		qsort(in_pack.array, in_pack.nr, sizeof(in_pack.array[0]),
+		      ofscmp);
+		for (i = 0; i < in_pack.nr; i++) {
+			struct object *o = in_pack.array[i].object;
+			add_object_entry(o->sha1, o->type, "", 0);
+		}
+	}
+	free(in_pack.array);
+}
+
+static int has_sha1_pack_kept_or_nonlocal(const unsigned char *sha1)
+{
+	static struct packed_git *last_found = (void *)1;
+	struct packed_git *p;
+
+	p = (last_found != (void *)1) ? last_found : packed_git;
+
+	while (p) {
+		if ((!p->pack_local || p->pack_keep) &&
+			find_pack_entry_one(sha1, p)) {
+			last_found = p;
+			return 1;
+		}
+		if (p == last_found)
+			p = packed_git;
+		else
+			p = p->next;
+		if (p == last_found)
+			p = p->next;
+	}
+	return 0;
+}
+
+static void loosen_unused_packed_objects(struct rev_info *revs)
+{
+	struct packed_git *p;
+	uint32_t i;
+	const unsigned char *sha1;
+
+	for (p = packed_git; p; p = p->next) {
+		if (!p->pack_local || p->pack_keep)
+			continue;
+
+		if (open_pack_index(p))
+			die("cannot open pack index");
+
+		for (i = 0; i < p->num_objects; i++) {
+			sha1 = nth_packed_object_sha1(p, i);
+			if (!locate_object_entry(sha1) &&
+				!has_sha1_pack_kept_or_nonlocal(sha1))
+				if (force_object_loose(sha1, p->mtime))
+					die("unable to force loose object");
+		}
+	}
+}
+
+static void get_object_list(int ac, const char **av)
+{
+	struct rev_info revs;
+	char line[1000];
+	int flags = 0;
+
+	init_revisions(&revs, NULL);
+	save_commit_buffer = 0;
+	setup_revisions(ac, av, &revs, NULL);
+
+	while (fgets(line, sizeof(line), stdin) != NULL) {
+		int len = strlen(line);
+		if (len && line[len - 1] == '\n')
+			line[--len] = 0;
+		if (!len)
+			break;
+		if (*line == '-') {
+			if (!strcmp(line, "--not")) {
+				flags ^= UNINTERESTING;
+				continue;
+			}
+			die("not a rev '%s'", line);
+		}
+		if (handle_revision_arg(line, &revs, flags, 1))
+			die("bad revision '%s'", line);
+	}
+
+	if (prepare_revision_walk(&revs))
+		die("revision walk setup failed");
+	mark_edges_uninteresting(revs.commits, &revs, show_edge);
+	traverse_commit_list(&revs, show_commit, show_object, NULL);
+
+	if (keep_unreachable)
+		add_objects_in_unpacked_packs(&revs);
+	if (unpack_unreachable)
+		loosen_unused_packed_objects(&revs);
+}
+
+int cmd_pack_objects(int argc, const char **argv, const char *prefix)
+{
+	int use_internal_rev_list = 0;
+	int thin = 0;
+	int all_progress_implied = 0;
+	uint32_t i;
+	const char **rp_av;
+	int rp_ac_alloc = 64;
+	int rp_ac;
+
+	read_replace_refs = 0;
+
+	rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
+
+	rp_av[0] = "pack-objects";
+	rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
+	rp_ac = 2;
+
+	git_config(git_pack_config, NULL);
+	if (!pack_compression_seen && core_compression_seen)
+		pack_compression_level = core_compression_level;
+
+	progress = isatty(2);
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (*arg != '-')
+			break;
+
+		if (!strcmp("--non-empty", arg)) {
+			non_empty = 1;
+			continue;
+		}
+		if (!strcmp("--local", arg)) {
+			local = 1;
+			continue;
+		}
+		if (!strcmp("--incremental", arg)) {
+			incremental = 1;
+			continue;
+		}
+		if (!strcmp("--honor-pack-keep", arg)) {
+			ignore_packed_keep = 1;
+			continue;
+		}
+		if (!prefixcmp(arg, "--compression=")) {
+			char *end;
+			int level = strtoul(arg+14, &end, 0);
+			if (!arg[14] || *end)
+				usage(pack_usage);
+			if (level == -1)
+				level = Z_DEFAULT_COMPRESSION;
+			else if (level < 0 || level > Z_BEST_COMPRESSION)
+				die("bad pack compression level %d", level);
+			pack_compression_level = level;
+			continue;
+		}
+		if (!prefixcmp(arg, "--max-pack-size=")) {
+			pack_size_limit_cfg = 0;
+			if (!git_parse_ulong(arg+16, &pack_size_limit))
+				usage(pack_usage);
+			continue;
+		}
+		if (!prefixcmp(arg, "--window=")) {
+			char *end;
+			window = strtoul(arg+9, &end, 0);
+			if (!arg[9] || *end)
+				usage(pack_usage);
+			continue;
+		}
+		if (!prefixcmp(arg, "--window-memory=")) {
+			if (!git_parse_ulong(arg+16, &window_memory_limit))
+				usage(pack_usage);
+			continue;
+		}
+		if (!prefixcmp(arg, "--threads=")) {
+			char *end;
+			delta_search_threads = strtoul(arg+10, &end, 0);
+			if (!arg[10] || *end || delta_search_threads < 0)
+				usage(pack_usage);
+#ifdef NO_PTHREADS
+			if (delta_search_threads != 1)
+				warning("no threads support, "
+					"ignoring %s", arg);
+#endif
+			continue;
+		}
+		if (!prefixcmp(arg, "--depth=")) {
+			char *end;
+			depth = strtoul(arg+8, &end, 0);
+			if (!arg[8] || *end)
+				usage(pack_usage);
+			continue;
+		}
+		if (!strcmp("--progress", arg)) {
+			progress = 1;
+			continue;
+		}
+		if (!strcmp("--all-progress", arg)) {
+			progress = 2;
+			continue;
+		}
+		if (!strcmp("--all-progress-implied", arg)) {
+			all_progress_implied = 1;
+			continue;
+		}
+		if (!strcmp("-q", arg)) {
+			progress = 0;
+			continue;
+		}
+		if (!strcmp("--no-reuse-delta", arg)) {
+			reuse_delta = 0;
+			continue;
+		}
+		if (!strcmp("--no-reuse-object", arg)) {
+			reuse_object = reuse_delta = 0;
+			continue;
+		}
+		if (!strcmp("--delta-base-offset", arg)) {
+			allow_ofs_delta = 1;
+			continue;
+		}
+		if (!strcmp("--stdout", arg)) {
+			pack_to_stdout = 1;
+			continue;
+		}
+		if (!strcmp("--revs", arg)) {
+			use_internal_rev_list = 1;
+			continue;
+		}
+		if (!strcmp("--keep-unreachable", arg)) {
+			keep_unreachable = 1;
+			continue;
+		}
+		if (!strcmp("--unpack-unreachable", arg)) {
+			unpack_unreachable = 1;
+			continue;
+		}
+		if (!strcmp("--include-tag", arg)) {
+			include_tag = 1;
+			continue;
+		}
+		if (!strcmp("--unpacked", arg) ||
+		    !strcmp("--reflog", arg) ||
+		    !strcmp("--all", arg)) {
+			use_internal_rev_list = 1;
+			if (rp_ac >= rp_ac_alloc - 1) {
+				rp_ac_alloc = alloc_nr(rp_ac_alloc);
+				rp_av = xrealloc(rp_av,
+						 rp_ac_alloc * sizeof(*rp_av));
+			}
+			rp_av[rp_ac++] = arg;
+			continue;
+		}
+		if (!strcmp("--thin", arg)) {
+			use_internal_rev_list = 1;
+			thin = 1;
+			rp_av[1] = "--objects-edge";
+			continue;
+		}
+		if (!prefixcmp(arg, "--index-version=")) {
+			char *c;
+			pack_idx_default_version = strtoul(arg + 16, &c, 10);
+			if (pack_idx_default_version > 2)
+				die("bad %s", arg);
+			if (*c == ',')
+				pack_idx_off32_limit = strtoul(c+1, &c, 0);
+			if (*c || pack_idx_off32_limit & 0x80000000)
+				die("bad %s", arg);
+			continue;
+		}
+		if (!strcmp(arg, "--keep-true-parents")) {
+			grafts_replace_parents = 0;
+			continue;
+		}
+		usage(pack_usage);
+	}
+
+	/* Traditionally "pack-objects [options] base extra" failed;
+	 * we would however want to take refs parameter that would
+	 * have been given to upstream rev-list ourselves, which means
+	 * we somehow want to say what the base name is.  So the
+	 * syntax would be:
+	 *
+	 * pack-objects [options] base <refs...>
+	 *
+	 * in other words, we would treat the first non-option as the
+	 * base_name and send everything else to the internal revision
+	 * walker.
+	 */
+
+	if (!pack_to_stdout)
+		base_name = argv[i++];
+
+	if (pack_to_stdout != !base_name)
+		usage(pack_usage);
+
+	if (!pack_to_stdout && !pack_size_limit)
+		pack_size_limit = pack_size_limit_cfg;
+	if (pack_to_stdout && pack_size_limit)
+		die("--max-pack-size cannot be used to build a pack for transfer.");
+	if (pack_size_limit && pack_size_limit < 1024*1024) {
+		warning("minimum pack size limit is 1 MiB");
+		pack_size_limit = 1024*1024;
+	}
+
+	if (!pack_to_stdout && thin)
+		die("--thin cannot be used to build an indexable pack.");
+
+	if (keep_unreachable && unpack_unreachable)
+		die("--keep-unreachable and --unpack-unreachable are incompatible.");
+
+	if (progress && all_progress_implied)
+		progress = 2;
+
+	prepare_packed_git();
+
+	if (progress)
+		progress_state = start_progress("Counting objects", 0);
+	if (!use_internal_rev_list)
+		read_object_list_from_stdin();
+	else {
+		rp_av[rp_ac] = NULL;
+		get_object_list(rp_ac, rp_av);
+	}
+	cleanup_preferred_base();
+	if (include_tag && nr_result)
+		for_each_ref(add_ref_tag, NULL);
+	stop_progress(&progress_state);
+
+	if (non_empty && !nr_result)
+		return 0;
+	if (nr_result)
+		prepare_pack(window, depth);
+	write_pack_file();
+	if (progress)
+		fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
+			" reused %"PRIu32" (delta %"PRIu32")\n",
+			written, written_delta, reused, reused_delta);
+	return 0;
+}
diff --git a/builtin/pack-redundant.c b/builtin/pack-redundant.c
new file mode 100644
index 0000000..41e1615
--- /dev/null
+++ b/builtin/pack-redundant.c
@@ -0,0 +1,696 @@
+/*
+*
+* Copyright 2005, Lukas Sandstrom <lukass@etek.chalmers.se>
+*
+* This file is licensed under the GPL v2.
+*
+*/
+
+#include "cache.h"
+#include "exec_cmd.h"
+
+#define BLKSIZE 512
+
+static const char pack_redundant_usage[] =
+"git pack-redundant [ --verbose ] [ --alt-odb ] < --all | <.pack filename> ...>";
+
+static int load_all_packs, verbose, alt_odb;
+
+struct llist_item {
+	struct llist_item *next;
+	const unsigned char *sha1;
+};
+static struct llist {
+	struct llist_item *front;
+	struct llist_item *back;
+	size_t size;
+} *all_objects; /* all objects which must be present in local packfiles */
+
+static struct pack_list {
+	struct pack_list *next;
+	struct packed_git *pack;
+	struct llist *unique_objects;
+	struct llist *all_objects;
+} *local_packs = NULL, *altodb_packs = NULL;
+
+struct pll {
+	struct pll *next;
+	struct pack_list *pl;
+};
+
+static struct llist_item *free_nodes;
+
+static inline void llist_item_put(struct llist_item *item)
+{
+	item->next = free_nodes;
+	free_nodes = item;
+}
+
+static inline struct llist_item *llist_item_get(void)
+{
+	struct llist_item *new;
+	if ( free_nodes ) {
+		new = free_nodes;
+		free_nodes = free_nodes->next;
+	} else {
+		int i = 1;
+		new = xmalloc(sizeof(struct llist_item) * BLKSIZE);
+		for (; i < BLKSIZE; i++)
+			llist_item_put(&new[i]);
+	}
+	return new;
+}
+
+static void llist_free(struct llist *list)
+{
+	while ((list->back = list->front)) {
+		list->front = list->front->next;
+		llist_item_put(list->back);
+	}
+	free(list);
+}
+
+static inline void llist_init(struct llist **list)
+{
+	*list = xmalloc(sizeof(struct llist));
+	(*list)->front = (*list)->back = NULL;
+	(*list)->size = 0;
+}
+
+static struct llist * llist_copy(struct llist *list)
+{
+	struct llist *ret;
+	struct llist_item *new, *old, *prev;
+
+	llist_init(&ret);
+
+	if ((ret->size = list->size) == 0)
+		return ret;
+
+	new = ret->front = llist_item_get();
+	new->sha1 = list->front->sha1;
+
+	old = list->front->next;
+	while (old) {
+		prev = new;
+		new = llist_item_get();
+		prev->next = new;
+		new->sha1 = old->sha1;
+		old = old->next;
+	}
+	new->next = NULL;
+	ret->back = new;
+
+	return ret;
+}
+
+static inline struct llist_item *llist_insert(struct llist *list,
+					      struct llist_item *after,
+					       const unsigned char *sha1)
+{
+	struct llist_item *new = llist_item_get();
+	new->sha1 = sha1;
+	new->next = NULL;
+
+	if (after != NULL) {
+		new->next = after->next;
+		after->next = new;
+		if (after == list->back)
+			list->back = new;
+	} else {/* insert in front */
+		if (list->size == 0)
+			list->back = new;
+		else
+			new->next = list->front;
+		list->front = new;
+	}
+	list->size++;
+	return new;
+}
+
+static inline struct llist_item *llist_insert_back(struct llist *list,
+						   const unsigned char *sha1)
+{
+	return llist_insert(list, list->back, sha1);
+}
+
+static inline struct llist_item *llist_insert_sorted_unique(struct llist *list,
+			const unsigned char *sha1, struct llist_item *hint)
+{
+	struct llist_item *prev = NULL, *l;
+
+	l = (hint == NULL) ? list->front : hint;
+	while (l) {
+		int cmp = hashcmp(l->sha1, sha1);
+		if (cmp > 0) { /* we insert before this entry */
+			return llist_insert(list, prev, sha1);
+		}
+		if (!cmp) { /* already exists */
+			return l;
+		}
+		prev = l;
+		l = l->next;
+	}
+	/* insert at the end */
+	return llist_insert_back(list, sha1);
+}
+
+/* returns a pointer to an item in front of sha1 */
+static inline struct llist_item * llist_sorted_remove(struct llist *list, const unsigned char *sha1, struct llist_item *hint)
+{
+	struct llist_item *prev, *l;
+
+redo_from_start:
+	l = (hint == NULL) ? list->front : hint;
+	prev = NULL;
+	while (l) {
+		int cmp = hashcmp(l->sha1, sha1);
+		if (cmp > 0) /* not in list, since sorted */
+			return prev;
+		if (!cmp) { /* found */
+			if (prev == NULL) {
+				if (hint != NULL && hint != list->front) {
+					/* we don't know the previous element */
+					hint = NULL;
+					goto redo_from_start;
+				}
+				list->front = l->next;
+			} else
+				prev->next = l->next;
+			if (l == list->back)
+				list->back = prev;
+			llist_item_put(l);
+			list->size--;
+			return prev;
+		}
+		prev = l;
+		l = l->next;
+	}
+	return prev;
+}
+
+/* computes A\B */
+static void llist_sorted_difference_inplace(struct llist *A,
+				     struct llist *B)
+{
+	struct llist_item *hint, *b;
+
+	hint = NULL;
+	b = B->front;
+
+	while (b) {
+		hint = llist_sorted_remove(A, b->sha1, hint);
+		b = b->next;
+	}
+}
+
+static inline struct pack_list * pack_list_insert(struct pack_list **pl,
+					   struct pack_list *entry)
+{
+	struct pack_list *p = xmalloc(sizeof(struct pack_list));
+	memcpy(p, entry, sizeof(struct pack_list));
+	p->next = *pl;
+	*pl = p;
+	return p;
+}
+
+static inline size_t pack_list_size(struct pack_list *pl)
+{
+	size_t ret = 0;
+	while (pl) {
+		ret++;
+		pl = pl->next;
+	}
+	return ret;
+}
+
+static struct pack_list * pack_list_difference(const struct pack_list *A,
+					       const struct pack_list *B)
+{
+	struct pack_list *ret;
+	const struct pack_list *pl;
+
+	if (A == NULL)
+		return NULL;
+
+	pl = B;
+	while (pl != NULL) {
+		if (A->pack == pl->pack)
+			return pack_list_difference(A->next, B);
+		pl = pl->next;
+	}
+	ret = xmalloc(sizeof(struct pack_list));
+	memcpy(ret, A, sizeof(struct pack_list));
+	ret->next = pack_list_difference(A->next, B);
+	return ret;
+}
+
+static void cmp_two_packs(struct pack_list *p1, struct pack_list *p2)
+{
+	unsigned long p1_off = 0, p2_off = 0, p1_step, p2_step;
+	const unsigned char *p1_base, *p2_base;
+	struct llist_item *p1_hint = NULL, *p2_hint = NULL;
+
+	p1_base = p1->pack->index_data;
+	p2_base = p2->pack->index_data;
+	p1_base += 256 * 4 + ((p1->pack->index_version < 2) ? 4 : 8);
+	p2_base += 256 * 4 + ((p2->pack->index_version < 2) ? 4 : 8);
+	p1_step = (p1->pack->index_version < 2) ? 24 : 20;
+	p2_step = (p2->pack->index_version < 2) ? 24 : 20;
+
+	while (p1_off < p1->pack->num_objects * p1_step &&
+	       p2_off < p2->pack->num_objects * p2_step)
+	{
+		int cmp = hashcmp(p1_base + p1_off, p2_base + p2_off);
+		/* cmp ~ p1 - p2 */
+		if (cmp == 0) {
+			p1_hint = llist_sorted_remove(p1->unique_objects,
+					p1_base + p1_off, p1_hint);
+			p2_hint = llist_sorted_remove(p2->unique_objects,
+					p1_base + p1_off, p2_hint);
+			p1_off += p1_step;
+			p2_off += p2_step;
+			continue;
+		}
+		if (cmp < 0) { /* p1 has the object, p2 doesn't */
+			p1_off += p1_step;
+		} else { /* p2 has the object, p1 doesn't */
+			p2_off += p2_step;
+		}
+	}
+}
+
+static void pll_free(struct pll *l)
+{
+	struct pll *old;
+	struct pack_list *opl;
+
+	while (l) {
+		old = l;
+		while (l->pl) {
+			opl = l->pl;
+			l->pl = opl->next;
+			free(opl);
+		}
+		l = l->next;
+		free(old);
+	}
+}
+
+/* all the permutations have to be free()d at the same time,
+ * since they refer to each other
+ */
+static struct pll * get_permutations(struct pack_list *list, int n)
+{
+	struct pll *subset, *ret = NULL, *new_pll = NULL, *pll;
+
+	if (list == NULL || pack_list_size(list) < n || n == 0)
+		return NULL;
+
+	if (n == 1) {
+		while (list) {
+			new_pll = xmalloc(sizeof(pll));
+			new_pll->pl = NULL;
+			pack_list_insert(&new_pll->pl, list);
+			new_pll->next = ret;
+			ret = new_pll;
+			list = list->next;
+		}
+		return ret;
+	}
+
+	while (list->next) {
+		subset = get_permutations(list->next, n - 1);
+		while (subset) {
+			new_pll = xmalloc(sizeof(pll));
+			new_pll->pl = subset->pl;
+			pack_list_insert(&new_pll->pl, list);
+			new_pll->next = ret;
+			ret = new_pll;
+			subset = subset->next;
+		}
+		list = list->next;
+	}
+	return ret;
+}
+
+static int is_superset(struct pack_list *pl, struct llist *list)
+{
+	struct llist *diff;
+
+	diff = llist_copy(list);
+
+	while (pl) {
+		llist_sorted_difference_inplace(diff, pl->all_objects);
+		if (diff->size == 0) { /* we're done */
+			llist_free(diff);
+			return 1;
+		}
+		pl = pl->next;
+	}
+	llist_free(diff);
+	return 0;
+}
+
+static size_t sizeof_union(struct packed_git *p1, struct packed_git *p2)
+{
+	size_t ret = 0;
+	unsigned long p1_off = 0, p2_off = 0, p1_step, p2_step;
+	const unsigned char *p1_base, *p2_base;
+
+	p1_base = p1->index_data;
+	p2_base = p2->index_data;
+	p1_base += 256 * 4 + ((p1->index_version < 2) ? 4 : 8);
+	p2_base += 256 * 4 + ((p2->index_version < 2) ? 4 : 8);
+	p1_step = (p1->index_version < 2) ? 24 : 20;
+	p2_step = (p2->index_version < 2) ? 24 : 20;
+
+	while (p1_off < p1->num_objects * p1_step &&
+	       p2_off < p2->num_objects * p2_step)
+	{
+		int cmp = hashcmp(p1_base + p1_off, p2_base + p2_off);
+		/* cmp ~ p1 - p2 */
+		if (cmp == 0) {
+			ret++;
+			p1_off += p1_step;
+			p2_off += p2_step;
+			continue;
+		}
+		if (cmp < 0) { /* p1 has the object, p2 doesn't */
+			p1_off += p1_step;
+		} else { /* p2 has the object, p1 doesn't */
+			p2_off += p2_step;
+		}
+	}
+	return ret;
+}
+
+/* another O(n^2) function ... */
+static size_t get_pack_redundancy(struct pack_list *pl)
+{
+	struct pack_list *subset;
+	size_t ret = 0;
+
+	if (pl == NULL)
+		return 0;
+
+	while ((subset = pl->next)) {
+		while (subset) {
+			ret += sizeof_union(pl->pack, subset->pack);
+			subset = subset->next;
+		}
+		pl = pl->next;
+	}
+	return ret;
+}
+
+static inline off_t pack_set_bytecount(struct pack_list *pl)
+{
+	off_t ret = 0;
+	while (pl) {
+		ret += pl->pack->pack_size;
+		ret += pl->pack->index_size;
+		pl = pl->next;
+	}
+	return ret;
+}
+
+static void minimize(struct pack_list **min)
+{
+	struct pack_list *pl, *unique = NULL,
+		*non_unique = NULL, *min_perm = NULL;
+	struct pll *perm, *perm_all, *perm_ok = NULL, *new_perm;
+	struct llist *missing;
+	off_t min_perm_size = 0, perm_size;
+	int n;
+
+	pl = local_packs;
+	while (pl) {
+		if (pl->unique_objects->size)
+			pack_list_insert(&unique, pl);
+		else
+			pack_list_insert(&non_unique, pl);
+		pl = pl->next;
+	}
+	/* find out which objects are missing from the set of unique packs */
+	missing = llist_copy(all_objects);
+	pl = unique;
+	while (pl) {
+		llist_sorted_difference_inplace(missing, pl->all_objects);
+		pl = pl->next;
+	}
+
+	/* return if there are no objects missing from the unique set */
+	if (missing->size == 0) {
+		*min = unique;
+		return;
+	}
+
+	/* find the permutations which contain all missing objects */
+	for (n = 1; n <= pack_list_size(non_unique) && !perm_ok; n++) {
+		perm_all = perm = get_permutations(non_unique, n);
+		while (perm) {
+			if (is_superset(perm->pl, missing)) {
+				new_perm = xmalloc(sizeof(struct pll));
+				memcpy(new_perm, perm, sizeof(struct pll));
+				new_perm->next = perm_ok;
+				perm_ok = new_perm;
+			}
+			perm = perm->next;
+		}
+		if (perm_ok)
+			break;
+		pll_free(perm_all);
+	}
+	if (perm_ok == NULL)
+		die("Internal error: No complete sets found!");
+
+	/* find the permutation with the smallest size */
+	perm = perm_ok;
+	while (perm) {
+		perm_size = pack_set_bytecount(perm->pl);
+		if (!min_perm_size || min_perm_size > perm_size) {
+			min_perm_size = perm_size;
+			min_perm = perm->pl;
+		}
+		perm = perm->next;
+	}
+	*min = min_perm;
+	/* add the unique packs to the list */
+	pl = unique;
+	while (pl) {
+		pack_list_insert(min, pl);
+		pl = pl->next;
+	}
+}
+
+static void load_all_objects(void)
+{
+	struct pack_list *pl = local_packs;
+	struct llist_item *hint, *l;
+
+	llist_init(&all_objects);
+
+	while (pl) {
+		hint = NULL;
+		l = pl->all_objects->front;
+		while (l) {
+			hint = llist_insert_sorted_unique(all_objects,
+							  l->sha1, hint);
+			l = l->next;
+		}
+		pl = pl->next;
+	}
+	/* remove objects present in remote packs */
+	pl = altodb_packs;
+	while (pl) {
+		llist_sorted_difference_inplace(all_objects, pl->all_objects);
+		pl = pl->next;
+	}
+}
+
+/* this scales like O(n^2) */
+static void cmp_local_packs(void)
+{
+	struct pack_list *subset, *pl = local_packs;
+
+	while ((subset = pl)) {
+		while ((subset = subset->next))
+			cmp_two_packs(pl, subset);
+		pl = pl->next;
+	}
+}
+
+static void scan_alt_odb_packs(void)
+{
+	struct pack_list *local, *alt;
+
+	alt = altodb_packs;
+	while (alt) {
+		local = local_packs;
+		while (local) {
+			llist_sorted_difference_inplace(local->unique_objects,
+							alt->all_objects);
+			local = local->next;
+		}
+		llist_sorted_difference_inplace(all_objects, alt->all_objects);
+		alt = alt->next;
+	}
+}
+
+static struct pack_list * add_pack(struct packed_git *p)
+{
+	struct pack_list l;
+	unsigned long off = 0, step;
+	const unsigned char *base;
+
+	if (!p->pack_local && !(alt_odb || verbose))
+		return NULL;
+
+	l.pack = p;
+	llist_init(&l.all_objects);
+
+	if (open_pack_index(p))
+		return NULL;
+
+	base = p->index_data;
+	base += 256 * 4 + ((p->index_version < 2) ? 4 : 8);
+	step = (p->index_version < 2) ? 24 : 20;
+	while (off < p->num_objects * step) {
+		llist_insert_back(l.all_objects, base + off);
+		off += step;
+	}
+	/* this list will be pruned in cmp_two_packs later */
+	l.unique_objects = llist_copy(l.all_objects);
+	if (p->pack_local)
+		return pack_list_insert(&local_packs, &l);
+	else
+		return pack_list_insert(&altodb_packs, &l);
+}
+
+static struct pack_list * add_pack_file(const char *filename)
+{
+	struct packed_git *p = packed_git;
+
+	if (strlen(filename) < 40)
+		die("Bad pack filename: %s", filename);
+
+	while (p) {
+		if (strstr(p->pack_name, filename))
+			return add_pack(p);
+		p = p->next;
+	}
+	die("Filename %s not found in packed_git", filename);
+}
+
+static void load_all(void)
+{
+	struct packed_git *p = packed_git;
+
+	while (p) {
+		add_pack(p);
+		p = p->next;
+	}
+}
+
+int cmd_pack_redundant(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	struct pack_list *min, *red, *pl;
+	struct llist *ignore;
+	unsigned char *sha1;
+	char buf[42]; /* 40 byte sha1 + \n + \0 */
+
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage(pack_redundant_usage);
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!strcmp(arg, "--")) {
+			i++;
+			break;
+		}
+		if (!strcmp(arg, "--all")) {
+			load_all_packs = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--verbose")) {
+			verbose = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--alt-odb")) {
+			alt_odb = 1;
+			continue;
+		}
+		if (*arg == '-')
+			usage(pack_redundant_usage);
+		else
+			break;
+	}
+
+	prepare_packed_git();
+
+	if (load_all_packs)
+		load_all();
+	else
+		while (*(argv + i) != NULL)
+			add_pack_file(*(argv + i++));
+
+	if (local_packs == NULL)
+		die("Zero packs found!");
+
+	load_all_objects();
+
+	cmp_local_packs();
+	if (alt_odb)
+		scan_alt_odb_packs();
+
+	/* ignore objects given on stdin */
+	llist_init(&ignore);
+	if (!isatty(0)) {
+		while (fgets(buf, sizeof(buf), stdin)) {
+			sha1 = xmalloc(20);
+			if (get_sha1_hex(buf, sha1))
+				die("Bad sha1 on stdin: %s", buf);
+			llist_insert_sorted_unique(ignore, sha1, NULL);
+		}
+	}
+	llist_sorted_difference_inplace(all_objects, ignore);
+	pl = local_packs;
+	while (pl) {
+		llist_sorted_difference_inplace(pl->unique_objects, ignore);
+		pl = pl->next;
+	}
+
+	minimize(&min);
+
+	if (verbose) {
+		fprintf(stderr, "There are %lu packs available in alt-odbs.\n",
+			(unsigned long)pack_list_size(altodb_packs));
+		fprintf(stderr, "The smallest (bytewise) set of packs is:\n");
+		pl = min;
+		while (pl) {
+			fprintf(stderr, "\t%s\n", pl->pack->pack_name);
+			pl = pl->next;
+		}
+		fprintf(stderr, "containing %lu duplicate objects "
+				"with a total size of %lukb.\n",
+			(unsigned long)get_pack_redundancy(min),
+			(unsigned long)pack_set_bytecount(min)/1024);
+		fprintf(stderr, "A total of %lu unique objects were considered.\n",
+			(unsigned long)all_objects->size);
+		fprintf(stderr, "Redundant packs (with indexes):\n");
+	}
+	pl = red = pack_list_difference(local_packs, min);
+	while (pl) {
+		printf("%s\n%s\n",
+		       sha1_pack_index_name(pl->pack->sha1),
+		       pl->pack->pack_name);
+		pl = pl->next;
+	}
+	if (verbose)
+		fprintf(stderr, "%luMB of redundant packs in total.\n",
+			(unsigned long)pack_set_bytecount(red)/(1024*1024));
+
+	return 0;
+}
diff --git a/builtin/pack-refs.c b/builtin/pack-refs.c
new file mode 100644
index 0000000..091860b
--- /dev/null
+++ b/builtin/pack-refs.c
@@ -0,0 +1,21 @@
+#include "cache.h"
+#include "parse-options.h"
+#include "pack-refs.h"
+
+static char const * const pack_refs_usage[] = {
+	"git pack-refs [options]",
+	NULL
+};
+
+int cmd_pack_refs(int argc, const char **argv, const char *prefix)
+{
+	unsigned int flags = PACK_REFS_PRUNE;
+	struct option opts[] = {
+		OPT_BIT(0, "all",   &flags, "pack everything", PACK_REFS_ALL),
+		OPT_BIT(0, "prune", &flags, "prune loose refs (default)", PACK_REFS_PRUNE),
+		OPT_END(),
+	};
+	if (parse_options(argc, argv, prefix, opts, pack_refs_usage, 0))
+		usage_with_options(pack_refs_usage, opts);
+	return pack_refs(flags);
+}
diff --git a/builtin/patch-id.c b/builtin/patch-id.c
new file mode 100644
index 0000000..af0911e
--- /dev/null
+++ b/builtin/patch-id.c
@@ -0,0 +1,85 @@
+#include "cache.h"
+#include "exec_cmd.h"
+
+static void flush_current_id(int patchlen, unsigned char *id, git_SHA_CTX *c)
+{
+	unsigned char result[20];
+	char name[50];
+
+	if (!patchlen)
+		return;
+
+	git_SHA1_Final(result, c);
+	memcpy(name, sha1_to_hex(id), 41);
+	printf("%s %s\n", sha1_to_hex(result), name);
+	git_SHA1_Init(c);
+}
+
+static int remove_space(char *line)
+{
+	char *src = line;
+	char *dst = line;
+	unsigned char c;
+
+	while ((c = *src++) != '\0') {
+		if (!isspace(c))
+			*dst++ = c;
+	}
+	return dst - line;
+}
+
+static void generate_id_list(void)
+{
+	static unsigned char sha1[20];
+	static char line[1000];
+	git_SHA_CTX ctx;
+	int patchlen = 0;
+
+	git_SHA1_Init(&ctx);
+	while (fgets(line, sizeof(line), stdin) != NULL) {
+		unsigned char n[20];
+		char *p = line;
+		int len;
+
+		if (!memcmp(line, "diff-tree ", 10))
+			p += 10;
+		else if (!memcmp(line, "commit ", 7))
+			p += 7;
+
+		if (!get_sha1_hex(p, n)) {
+			flush_current_id(patchlen, sha1, &ctx);
+			hashcpy(sha1, n);
+			patchlen = 0;
+			continue;
+		}
+
+		/* Ignore commit comments */
+		if (!patchlen && memcmp(line, "diff ", 5))
+			continue;
+
+		/* Ignore git-diff index header */
+		if (!memcmp(line, "index ", 6))
+			continue;
+
+		/* Ignore line numbers when computing the SHA1 of the patch */
+		if (!memcmp(line, "@@ -", 4))
+			continue;
+
+		/* Compute the sha without whitespace */
+		len = remove_space(line);
+		patchlen += len;
+		git_SHA1_Update(&ctx, line, len);
+	}
+	flush_current_id(patchlen, sha1, &ctx);
+}
+
+static const char patch_id_usage[] = "git patch-id < patch";
+
+int cmd_patch_id(int argc, const char **argv, const char *prefix)
+{
+	if (argc != 1)
+		usage(patch_id_usage);
+
+	generate_id_list();
+	return 0;
+}
diff --git a/builtin/prune-packed.c b/builtin/prune-packed.c
new file mode 100644
index 0000000..f9463de
--- /dev/null
+++ b/builtin/prune-packed.c
@@ -0,0 +1,86 @@
+#include "builtin.h"
+#include "cache.h"
+#include "progress.h"
+#include "parse-options.h"
+
+static const char * const prune_packed_usage[] = {
+	"git prune-packed [-n|--dry-run] [-q|--quiet]",
+	NULL
+};
+
+#define DRY_RUN 01
+#define VERBOSE 02
+
+static struct progress *progress;
+
+static void prune_dir(int i, DIR *dir, char *pathname, int len, int opts)
+{
+	struct dirent *de;
+	char hex[40];
+
+	sprintf(hex, "%02x", i);
+	while ((de = readdir(dir)) != NULL) {
+		unsigned char sha1[20];
+		if (strlen(de->d_name) != 38)
+			continue;
+		memcpy(hex+2, de->d_name, 38);
+		if (get_sha1_hex(hex, sha1))
+			continue;
+		if (!has_sha1_pack(sha1))
+			continue;
+		memcpy(pathname + len, de->d_name, 38);
+		if (opts & DRY_RUN)
+			printf("rm -f %s\n", pathname);
+		else
+			unlink_or_warn(pathname);
+		display_progress(progress, i + 1);
+	}
+	pathname[len] = 0;
+	rmdir(pathname);
+}
+
+void prune_packed_objects(int opts)
+{
+	int i;
+	static char pathname[PATH_MAX];
+	const char *dir = get_object_directory();
+	int len = strlen(dir);
+
+	if (opts == VERBOSE)
+		progress = start_progress_delay("Removing duplicate objects",
+			256, 95, 2);
+
+	if (len > PATH_MAX - 42)
+		die("impossible object directory");
+	memcpy(pathname, dir, len);
+	if (len && pathname[len-1] != '/')
+		pathname[len++] = '/';
+	for (i = 0; i < 256; i++) {
+		DIR *d;
+
+		display_progress(progress, i + 1);
+		sprintf(pathname + len, "%02x/", i);
+		d = opendir(pathname);
+		if (!d)
+			continue;
+		prune_dir(i, d, pathname, len + 3, opts);
+		closedir(d);
+	}
+	stop_progress(&progress);
+}
+
+int cmd_prune_packed(int argc, const char **argv, const char *prefix)
+{
+	int opts = isatty(2) ? VERBOSE : 0;
+	const struct option prune_packed_options[] = {
+		OPT_BIT('n', "dry-run", &opts, "dry run", DRY_RUN),
+		OPT_NEGBIT('q', "quiet", &opts, "be quiet", VERBOSE),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, prune_packed_options,
+			     prune_packed_usage, 0);
+
+	prune_packed_objects(opts);
+	return 0;
+}
diff --git a/builtin/prune.c b/builtin/prune.c
new file mode 100644
index 0000000..81f915ec
--- /dev/null
+++ b/builtin/prune.c
@@ -0,0 +1,166 @@
+#include "cache.h"
+#include "commit.h"
+#include "diff.h"
+#include "revision.h"
+#include "builtin.h"
+#include "reachable.h"
+#include "parse-options.h"
+#include "dir.h"
+
+static const char * const prune_usage[] = {
+	"git prune [-n] [-v] [--expire <time>] [--] [<head>...]",
+	NULL
+};
+static int show_only;
+static int verbose;
+static unsigned long expire;
+
+static int prune_tmp_object(const char *path, const char *filename)
+{
+	const char *fullpath = mkpath("%s/%s", path, filename);
+	struct stat st;
+	if (lstat(fullpath, &st))
+		return error("Could not stat '%s'", fullpath);
+	if (st.st_mtime > expire)
+		return 0;
+	printf("Removing stale temporary file %s\n", fullpath);
+	if (!show_only)
+		unlink_or_warn(fullpath);
+	return 0;
+}
+
+static int prune_object(char *path, const char *filename, const unsigned char *sha1)
+{
+	const char *fullpath = mkpath("%s/%s", path, filename);
+	struct stat st;
+	if (lstat(fullpath, &st))
+		return error("Could not stat '%s'", fullpath);
+	if (st.st_mtime > expire)
+		return 0;
+	if (show_only || verbose) {
+		enum object_type type = sha1_object_info(sha1, NULL);
+		printf("%s %s\n", sha1_to_hex(sha1),
+		       (type > 0) ? typename(type) : "unknown");
+	}
+	if (!show_only)
+		unlink_or_warn(fullpath);
+	return 0;
+}
+
+static int prune_dir(int i, char *path)
+{
+	DIR *dir = opendir(path);
+	struct dirent *de;
+
+	if (!dir)
+		return 0;
+
+	while ((de = readdir(dir)) != NULL) {
+		char name[100];
+		unsigned char sha1[20];
+
+		if (is_dot_or_dotdot(de->d_name))
+			continue;
+		if (strlen(de->d_name) == 38) {
+			sprintf(name, "%02x", i);
+			memcpy(name+2, de->d_name, 39);
+			if (get_sha1_hex(name, sha1) < 0)
+				break;
+
+			/*
+			 * Do we know about this object?
+			 * It must have been reachable
+			 */
+			if (lookup_object(sha1))
+				continue;
+
+			prune_object(path, de->d_name, sha1);
+			continue;
+		}
+		if (!prefixcmp(de->d_name, "tmp_obj_")) {
+			prune_tmp_object(path, de->d_name);
+			continue;
+		}
+		fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
+	}
+	if (!show_only)
+		rmdir(path);
+	closedir(dir);
+	return 0;
+}
+
+static void prune_object_dir(const char *path)
+{
+	int i;
+	for (i = 0; i < 256; i++) {
+		static char dir[4096];
+		sprintf(dir, "%s/%02x", path, i);
+		prune_dir(i, dir);
+	}
+}
+
+/*
+ * Write errors (particularly out of space) can result in
+ * failed temporary packs (and more rarely indexes and other
+ * files beginning with "tmp_") accumulating in the object
+ * and the pack directories.
+ */
+static void remove_temporary_files(const char *path)
+{
+	DIR *dir;
+	struct dirent *de;
+
+	dir = opendir(path);
+	if (!dir) {
+		fprintf(stderr, "Unable to open directory %s\n", path);
+		return;
+	}
+	while ((de = readdir(dir)) != NULL)
+		if (!prefixcmp(de->d_name, "tmp_"))
+			prune_tmp_object(path, de->d_name);
+	closedir(dir);
+}
+
+int cmd_prune(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info revs;
+	const struct option options[] = {
+		OPT_BOOLEAN('n', NULL, &show_only,
+			    "do not remove, show only"),
+		OPT_BOOLEAN('v', NULL, &verbose,
+			"report pruned objects"),
+		OPT_DATE(0, "expire", &expire,
+			 "expire objects older than <time>"),
+		OPT_END()
+	};
+	char *s;
+
+	expire = ULONG_MAX;
+	save_commit_buffer = 0;
+	read_replace_refs = 0;
+	init_revisions(&revs, prefix);
+
+	argc = parse_options(argc, argv, prefix, options, prune_usage, 0);
+	while (argc--) {
+		unsigned char sha1[20];
+		const char *name = *argv++;
+
+		if (!get_sha1(name, sha1)) {
+			struct object *object = parse_object(sha1);
+			if (!object)
+				die("bad object: %s", name);
+			add_pending_object(&revs, object, "");
+		}
+		else
+			die("unrecognized argument: %s", name);
+	}
+	mark_reachable_objects(&revs, 1);
+	prune_object_dir(get_object_directory());
+
+	prune_packed_objects(show_only);
+	remove_temporary_files(get_object_directory());
+	s = xstrdup(mkpath("%s/pack", get_object_directory()));
+	remove_temporary_files(s);
+	free(s);
+	return 0;
+}
diff --git a/builtin/push.c b/builtin/push.c
new file mode 100644
index 0000000..f7bc2b2
--- /dev/null
+++ b/builtin/push.c
@@ -0,0 +1,247 @@
+/*
+ * "git push"
+ */
+#include "cache.h"
+#include "refs.h"
+#include "run-command.h"
+#include "builtin.h"
+#include "remote.h"
+#include "transport.h"
+#include "parse-options.h"
+
+static const char * const push_usage[] = {
+	"git push [<options>] [<repository> <refspec>...]",
+	NULL,
+};
+
+static int thin;
+static int deleterefs;
+static const char *receivepack;
+
+static const char **refspec;
+static int refspec_nr;
+
+static void add_refspec(const char *ref)
+{
+	int nr = refspec_nr + 1;
+	refspec = xrealloc(refspec, nr * sizeof(char *));
+	refspec[nr-1] = ref;
+	refspec_nr = nr;
+}
+
+static void set_refspecs(const char **refs, int nr)
+{
+	int i;
+	for (i = 0; i < nr; i++) {
+		const char *ref = refs[i];
+		if (!strcmp("tag", ref)) {
+			char *tag;
+			int len;
+			if (nr <= ++i)
+				die("tag shorthand without <tag>");
+			len = strlen(refs[i]) + 11;
+			if (deleterefs) {
+				tag = xmalloc(len+1);
+				strcpy(tag, ":refs/tags/");
+			} else {
+				tag = xmalloc(len);
+				strcpy(tag, "refs/tags/");
+			}
+			strcat(tag, refs[i]);
+			ref = tag;
+		} else if (deleterefs && !strchr(ref, ':')) {
+			char *delref;
+			int len = strlen(ref)+1;
+			delref = xmalloc(len+1);
+			strcpy(delref, ":");
+			strcat(delref, ref);
+			ref = delref;
+		} else if (deleterefs)
+			die("--delete only accepts plain target ref names");
+		add_refspec(ref);
+	}
+}
+
+static void setup_push_tracking(void)
+{
+	struct strbuf refspec = STRBUF_INIT;
+	struct branch *branch = branch_get(NULL);
+	if (!branch)
+		die("You are not currently on a branch.");
+	if (!branch->merge_nr || !branch->merge)
+		die("The current branch %s is not tracking anything.",
+		    branch->name);
+	if (branch->merge_nr != 1)
+		die("The current branch %s is tracking multiple branches, "
+		    "refusing to push.", branch->name);
+	strbuf_addf(&refspec, "%s:%s", branch->name, branch->merge[0]->src);
+	add_refspec(refspec.buf);
+}
+
+static void setup_default_push_refspecs(void)
+{
+	switch (push_default) {
+	default:
+	case PUSH_DEFAULT_MATCHING:
+		add_refspec(":");
+		break;
+
+	case PUSH_DEFAULT_TRACKING:
+		setup_push_tracking();
+		break;
+
+	case PUSH_DEFAULT_CURRENT:
+		add_refspec("HEAD");
+		break;
+
+	case PUSH_DEFAULT_NOTHING:
+		die("You didn't specify any refspecs to push, and "
+		    "push.default is \"nothing\".");
+		break;
+	}
+}
+
+static int push_with_options(struct transport *transport, int flags)
+{
+	int err;
+	int nonfastforward;
+	if (receivepack)
+		transport_set_option(transport,
+				     TRANS_OPT_RECEIVEPACK, receivepack);
+	if (thin)
+		transport_set_option(transport, TRANS_OPT_THIN, "yes");
+
+	if (flags & TRANSPORT_PUSH_VERBOSE)
+		fprintf(stderr, "Pushing to %s\n", transport->url);
+	err = transport_push(transport, refspec_nr, refspec, flags,
+			     &nonfastforward);
+	if (err != 0)
+		error("failed to push some refs to '%s'", transport->url);
+
+	err |= transport_disconnect(transport);
+
+	if (!err)
+		return 0;
+
+	if (nonfastforward && advice_push_nonfastforward) {
+		printf("To prevent you from losing history, non-fast-forward updates were rejected\n"
+		       "Merge the remote changes before pushing again.  See the 'Note about\n"
+		       "fast-forwards' section of 'git push --help' for details.\n");
+	}
+
+	return 1;
+}
+
+static int do_push(const char *repo, int flags)
+{
+	int i, errs;
+	struct remote *remote = remote_get(repo);
+	const char **url;
+	int url_nr;
+
+	if (!remote) {
+		if (repo)
+			die("bad repository '%s'", repo);
+		die("No destination configured to push to.");
+	}
+
+	if (remote->mirror)
+		flags |= (TRANSPORT_PUSH_MIRROR|TRANSPORT_PUSH_FORCE);
+
+	if ((flags & TRANSPORT_PUSH_ALL) && refspec) {
+		if (!strcmp(*refspec, "refs/tags/*"))
+			return error("--all and --tags are incompatible");
+		return error("--all can't be combined with refspecs");
+	}
+
+	if ((flags & TRANSPORT_PUSH_MIRROR) && refspec) {
+		if (!strcmp(*refspec, "refs/tags/*"))
+			return error("--mirror and --tags are incompatible");
+		return error("--mirror can't be combined with refspecs");
+	}
+
+	if ((flags & (TRANSPORT_PUSH_ALL|TRANSPORT_PUSH_MIRROR)) ==
+				(TRANSPORT_PUSH_ALL|TRANSPORT_PUSH_MIRROR)) {
+		return error("--all and --mirror are incompatible");
+	}
+
+	if (!refspec && !(flags & TRANSPORT_PUSH_ALL)) {
+		if (remote->push_refspec_nr) {
+			refspec = remote->push_refspec;
+			refspec_nr = remote->push_refspec_nr;
+		} else if (!(flags & TRANSPORT_PUSH_MIRROR))
+			setup_default_push_refspecs();
+	}
+	errs = 0;
+	if (remote->pushurl_nr) {
+		url = remote->pushurl;
+		url_nr = remote->pushurl_nr;
+	} else {
+		url = remote->url;
+		url_nr = remote->url_nr;
+	}
+	if (url_nr) {
+		for (i = 0; i < url_nr; i++) {
+			struct transport *transport =
+				transport_get(remote, url[i]);
+			if (push_with_options(transport, flags))
+				errs++;
+		}
+	} else {
+		struct transport *transport =
+			transport_get(remote, NULL);
+
+		if (push_with_options(transport, flags))
+			errs++;
+	}
+	return !!errs;
+}
+
+int cmd_push(int argc, const char **argv, const char *prefix)
+{
+	int flags = 0;
+	int tags = 0;
+	int rc;
+	const char *repo = NULL;	/* default repository */
+	struct option options[] = {
+		OPT_BIT('q', "quiet", &flags, "be quiet", TRANSPORT_PUSH_QUIET),
+		OPT_BIT('v', "verbose", &flags, "be verbose", TRANSPORT_PUSH_VERBOSE),
+		OPT_STRING( 0 , "repo", &repo, "repository", "repository"),
+		OPT_BIT( 0 , "all", &flags, "push all refs", TRANSPORT_PUSH_ALL),
+		OPT_BIT( 0 , "mirror", &flags, "mirror all refs",
+			    (TRANSPORT_PUSH_MIRROR|TRANSPORT_PUSH_FORCE)),
+		OPT_BOOLEAN( 0, "delete", &deleterefs, "delete refs"),
+		OPT_BOOLEAN( 0 , "tags", &tags, "push tags (can't be used with --all or --mirror)"),
+		OPT_BIT('n' , "dry-run", &flags, "dry run", TRANSPORT_PUSH_DRY_RUN),
+		OPT_BIT( 0,  "porcelain", &flags, "machine-readable output", TRANSPORT_PUSH_PORCELAIN),
+		OPT_BIT('f', "force", &flags, "force updates", TRANSPORT_PUSH_FORCE),
+		OPT_BOOLEAN( 0 , "thin", &thin, "use thin pack"),
+		OPT_STRING( 0 , "receive-pack", &receivepack, "receive-pack", "receive pack program"),
+		OPT_STRING( 0 , "exec", &receivepack, "receive-pack", "receive pack program"),
+		OPT_BIT('u', "set-upstream", &flags, "set upstream for git pull/status",
+			TRANSPORT_PUSH_SET_UPSTREAM),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, prefix, options, push_usage, 0);
+
+	if (deleterefs && (tags || (flags & (TRANSPORT_PUSH_ALL | TRANSPORT_PUSH_MIRROR))))
+		die("--delete is incompatible with --all, --mirror and --tags");
+	if (deleterefs && argc < 2)
+		die("--delete doesn't make sense without any refs");
+
+	if (tags)
+		add_refspec("refs/tags/*");
+
+	if (argc > 0) {
+		repo = argv[0];
+		set_refspecs(argv + 1, argc - 1);
+	}
+
+	rc = do_push(repo, flags);
+	if (rc == -1)
+		usage_with_options(push_usage, options);
+	else
+		return rc;
+}
diff --git a/builtin/read-tree.c b/builtin/read-tree.c
new file mode 100644
index 0000000..8bdcab1
--- /dev/null
+++ b/builtin/read-tree.c
@@ -0,0 +1,235 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+
+#include "cache.h"
+#include "object.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "cache-tree.h"
+#include "unpack-trees.h"
+#include "dir.h"
+#include "builtin.h"
+#include "parse-options.h"
+#include "resolve-undo.h"
+
+static int nr_trees;
+static struct tree *trees[MAX_UNPACK_TREES];
+
+static int list_tree(unsigned char *sha1)
+{
+	struct tree *tree;
+
+	if (nr_trees >= MAX_UNPACK_TREES)
+		die("I cannot read more than %d trees", MAX_UNPACK_TREES);
+	tree = parse_tree_indirect(sha1);
+	if (!tree)
+		return -1;
+	trees[nr_trees++] = tree;
+	return 0;
+}
+
+static const char * const read_tree_usage[] = {
+	"git read-tree [[-m [--trivial] [--aggressive] | --reset | --prefix=<prefix>] [-u [--exclude-per-directory=<gitignore>] | -i]] [--no-sparse-checkout] [--index-output=<file>] <tree-ish1> [<tree-ish2> [<tree-ish3>]]",
+	NULL
+};
+
+static int index_output_cb(const struct option *opt, const char *arg,
+				 int unset)
+{
+	set_alternate_index_output(arg);
+	return 0;
+}
+
+static int exclude_per_directory_cb(const struct option *opt, const char *arg,
+				    int unset)
+{
+	struct dir_struct *dir;
+	struct unpack_trees_options *opts;
+
+	opts = (struct unpack_trees_options *)opt->value;
+
+	if (opts->dir)
+		die("more than one --exclude-per-directory given.");
+
+	dir = xcalloc(1, sizeof(*opts->dir));
+	dir->flags |= DIR_SHOW_IGNORED;
+	dir->exclude_per_dir = arg;
+	opts->dir = dir;
+	/* We do not need to nor want to do read-directory
+	 * here; we are merely interested in reusing the
+	 * per directory ignore stack mechanism.
+	 */
+	return 0;
+}
+
+static void debug_stage(const char *label, struct cache_entry *ce,
+			struct unpack_trees_options *o)
+{
+	printf("%s ", label);
+	if (!ce)
+		printf("(missing)\n");
+	else if (ce == o->df_conflict_entry)
+		printf("(conflict)\n");
+	else
+		printf("%06o #%d %s %.8s\n",
+		       ce->ce_mode, ce_stage(ce), ce->name,
+		       sha1_to_hex(ce->sha1));
+}
+
+static int debug_merge(struct cache_entry **stages, struct unpack_trees_options *o)
+{
+	int i;
+
+	printf("* %d-way merge\n", o->merge_size);
+	debug_stage("index", stages[0], o);
+	for (i = 1; i <= o->merge_size; i++) {
+		char buf[24];
+		sprintf(buf, "ent#%d", i);
+		debug_stage(buf, stages[i], o);
+	}
+	return 0;
+}
+
+static struct lock_file lock_file;
+
+int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
+{
+	int i, newfd, stage = 0;
+	unsigned char sha1[20];
+	struct tree_desc t[MAX_UNPACK_TREES];
+	struct unpack_trees_options opts;
+	int prefix_set = 0;
+	const struct option read_tree_options[] = {
+		{ OPTION_CALLBACK, 0, "index-output", NULL, "FILE",
+		  "write resulting index to <FILE>",
+		  PARSE_OPT_NONEG, index_output_cb },
+		OPT__VERBOSE(&opts.verbose_update),
+		OPT_GROUP("Merging"),
+		OPT_SET_INT('m', NULL, &opts.merge,
+			    "perform a merge in addition to a read", 1),
+		OPT_SET_INT(0, "trivial", &opts.trivial_merges_only,
+			    "3-way merge if no file level merging required", 1),
+		OPT_SET_INT(0, "aggressive", &opts.aggressive,
+			    "3-way merge in presence of adds and removes", 1),
+		OPT_SET_INT(0, "reset", &opts.reset,
+			    "same as -m, but discard unmerged entries", 1),
+		{ OPTION_STRING, 0, "prefix", &opts.prefix, "<subdirectory>/",
+		  "read the tree into the index under <subdirectory>/",
+		  PARSE_OPT_NONEG | PARSE_OPT_LITERAL_ARGHELP },
+		OPT_SET_INT('u', NULL, &opts.update,
+			    "update working tree with merge result", 1),
+		{ OPTION_CALLBACK, 0, "exclude-per-directory", &opts,
+		  "gitignore",
+		  "allow explicitly ignored files to be overwritten",
+		  PARSE_OPT_NONEG, exclude_per_directory_cb },
+		OPT_SET_INT('i', NULL, &opts.index_only,
+			    "don't check the working tree after merging", 1),
+		OPT_SET_INT(0, "no-sparse-checkout", &opts.skip_sparse_checkout,
+			    "skip applying sparse checkout filter", 1),
+		OPT_SET_INT(0, "debug-unpack", &opts.debug_unpack,
+			    "debug unpack-trees", 1),
+		OPT_END()
+	};
+
+	memset(&opts, 0, sizeof(opts));
+	opts.head_idx = -1;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
+
+	git_config(git_default_config, NULL);
+
+	argc = parse_options(argc, argv, unused_prefix, read_tree_options,
+			     read_tree_usage, 0);
+
+	newfd = hold_locked_index(&lock_file, 1);
+
+	prefix_set = opts.prefix ? 1 : 0;
+	if (1 < opts.merge + opts.reset + prefix_set)
+		die("Which one? -m, --reset, or --prefix?");
+
+	if (opts.reset || opts.merge || opts.prefix) {
+		if (read_cache_unmerged() && (opts.prefix || opts.merge))
+			die("You need to resolve your current index first");
+		stage = opts.merge = 1;
+	}
+	resolve_undo_clear();
+
+	for (i = 0; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (get_sha1(arg, sha1))
+			die("Not a valid object name %s", arg);
+		if (list_tree(sha1) < 0)
+			die("failed to unpack tree object %s", arg);
+		stage++;
+	}
+	if (1 < opts.index_only + opts.update)
+		die("-u and -i at the same time makes no sense");
+	if ((opts.update||opts.index_only) && !opts.merge)
+		die("%s is meaningless without -m, --reset, or --prefix",
+		    opts.update ? "-u" : "-i");
+	if ((opts.dir && !opts.update))
+		die("--exclude-per-directory is meaningless unless -u");
+	if (opts.merge && !opts.index_only)
+		setup_work_tree();
+
+	if (opts.merge) {
+		if (stage < 2)
+			die("just how do you expect me to merge %d trees?", stage-1);
+		switch (stage - 1) {
+		case 1:
+			opts.fn = opts.prefix ? bind_merge : oneway_merge;
+			break;
+		case 2:
+			opts.fn = twoway_merge;
+			opts.initial_checkout = is_cache_unborn();
+			break;
+		case 3:
+		default:
+			opts.fn = threeway_merge;
+			break;
+		}
+
+		if (stage - 1 >= 3)
+			opts.head_idx = stage - 2;
+		else
+			opts.head_idx = 1;
+	}
+
+	if (opts.debug_unpack)
+		opts.fn = debug_merge;
+
+	cache_tree_free(&active_cache_tree);
+	for (i = 0; i < nr_trees; i++) {
+		struct tree *tree = trees[i];
+		parse_tree(tree);
+		init_tree_desc(t+i, tree->buffer, tree->size);
+	}
+	if (unpack_trees(nr_trees, t, &opts))
+		return 128;
+
+	if (opts.debug_unpack)
+		return 0; /* do not write the index out */
+
+	/*
+	 * When reading only one tree (either the most basic form,
+	 * "-m ent" or "--reset ent" form), we can obtain a fully
+	 * valid cache-tree because the index must match exactly
+	 * what came from the tree.
+	 *
+	 * The same holds true if we are switching between two trees
+	 * using read-tree -m A B.  The index must match B after that.
+	 */
+	if (nr_trees == 1 && !opts.prefix)
+		prime_cache_tree(&active_cache_tree, trees[0]);
+	else if (nr_trees == 2 && opts.merge)
+		prime_cache_tree(&active_cache_tree, trees[1]);
+
+	if (write_cache(newfd, active_cache, active_nr) ||
+	    commit_locked_index(&lock_file))
+		die("unable to write new index file");
+	return 0;
+}
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
new file mode 100644
index 0000000..0559fcc
--- /dev/null
+++ b/builtin/receive-pack.c
@@ -0,0 +1,800 @@
+#include "cache.h"
+#include "pack.h"
+#include "refs.h"
+#include "pkt-line.h"
+#include "sideband.h"
+#include "run-command.h"
+#include "exec_cmd.h"
+#include "commit.h"
+#include "object.h"
+#include "remote.h"
+#include "transport.h"
+
+static const char receive_pack_usage[] = "git receive-pack <git-dir>";
+
+enum deny_action {
+	DENY_UNCONFIGURED,
+	DENY_IGNORE,
+	DENY_WARN,
+	DENY_REFUSE,
+};
+
+static int deny_deletes;
+static int deny_non_fast_forwards;
+static enum deny_action deny_current_branch = DENY_UNCONFIGURED;
+static enum deny_action deny_delete_current = DENY_UNCONFIGURED;
+static int receive_fsck_objects;
+static int receive_unpack_limit = -1;
+static int transfer_unpack_limit = -1;
+static int unpack_limit = 100;
+static int report_status;
+static int use_sideband;
+static int prefer_ofs_delta = 1;
+static int auto_update_server_info;
+static int auto_gc = 1;
+static const char *head_name;
+static int sent_capabilities;
+
+static enum deny_action parse_deny_action(const char *var, const char *value)
+{
+	if (value) {
+		if (!strcasecmp(value, "ignore"))
+			return DENY_IGNORE;
+		if (!strcasecmp(value, "warn"))
+			return DENY_WARN;
+		if (!strcasecmp(value, "refuse"))
+			return DENY_REFUSE;
+	}
+	if (git_config_bool(var, value))
+		return DENY_REFUSE;
+	return DENY_IGNORE;
+}
+
+static int receive_pack_config(const char *var, const char *value, void *cb)
+{
+	if (strcmp(var, "receive.denydeletes") == 0) {
+		deny_deletes = git_config_bool(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "receive.denynonfastforwards") == 0) {
+		deny_non_fast_forwards = git_config_bool(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "receive.unpacklimit") == 0) {
+		receive_unpack_limit = git_config_int(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "transfer.unpacklimit") == 0) {
+		transfer_unpack_limit = git_config_int(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "receive.fsckobjects") == 0) {
+		receive_fsck_objects = git_config_bool(var, value);
+		return 0;
+	}
+
+	if (!strcmp(var, "receive.denycurrentbranch")) {
+		deny_current_branch = parse_deny_action(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "receive.denydeletecurrent") == 0) {
+		deny_delete_current = parse_deny_action(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "repack.usedeltabaseoffset") == 0) {
+		prefer_ofs_delta = git_config_bool(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "receive.updateserverinfo") == 0) {
+		auto_update_server_info = git_config_bool(var, value);
+		return 0;
+	}
+
+	if (strcmp(var, "receive.autogc") == 0) {
+		auto_gc = git_config_bool(var, value);
+		return 0;
+	}
+
+	return git_default_config(var, value, cb);
+}
+
+static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+	if (sent_capabilities)
+		packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
+	else
+		packet_write(1, "%s %s%c%s%s\n",
+			     sha1_to_hex(sha1), path, 0,
+			     " report-status delete-refs side-band-64k",
+			     prefer_ofs_delta ? " ofs-delta" : "");
+	sent_capabilities = 1;
+	return 0;
+}
+
+static void write_head_info(void)
+{
+	for_each_ref(show_ref, NULL);
+	if (!sent_capabilities)
+		show_ref("capabilities^{}", null_sha1, 0, NULL);
+
+}
+
+struct command {
+	struct command *next;
+	const char *error_string;
+	unsigned char old_sha1[20];
+	unsigned char new_sha1[20];
+	char ref_name[FLEX_ARRAY]; /* more */
+};
+
+static struct command *commands;
+
+static const char pre_receive_hook[] = "hooks/pre-receive";
+static const char post_receive_hook[] = "hooks/post-receive";
+
+static void rp_error(const char *err, ...) __attribute__((format (printf, 1, 2)));
+static void rp_warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
+
+static void report_message(const char *prefix, const char *err, va_list params)
+{
+	int sz = strlen(prefix);
+	char msg[4096];
+
+	strncpy(msg, prefix, sz);
+	sz += vsnprintf(msg + sz, sizeof(msg) - sz, err, params);
+	if (sz > (sizeof(msg) - 1))
+		sz = sizeof(msg) - 1;
+	msg[sz++] = '\n';
+
+	if (use_sideband)
+		send_sideband(1, 2, msg, sz, use_sideband);
+	else
+		xwrite(2, msg, sz);
+}
+
+static void rp_warning(const char *err, ...)
+{
+	va_list params;
+	va_start(params, err);
+	report_message("warning: ", err, params);
+	va_end(params);
+}
+
+static void rp_error(const char *err, ...)
+{
+	va_list params;
+	va_start(params, err);
+	report_message("error: ", err, params);
+	va_end(params);
+}
+
+static int copy_to_sideband(int in, int out, void *arg)
+{
+	char data[128];
+	while (1) {
+		ssize_t sz = xread(in, data, sizeof(data));
+		if (sz <= 0)
+			break;
+		send_sideband(1, 2, data, sz, use_sideband);
+	}
+	close(in);
+	return 0;
+}
+
+static int run_receive_hook(const char *hook_name)
+{
+	static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
+	struct command *cmd;
+	struct child_process proc;
+	struct async muxer;
+	const char *argv[2];
+	int have_input = 0, code;
+
+	for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
+		if (!cmd->error_string)
+			have_input = 1;
+	}
+
+	if (!have_input || access(hook_name, X_OK) < 0)
+		return 0;
+
+	argv[0] = hook_name;
+	argv[1] = NULL;
+
+	memset(&proc, 0, sizeof(proc));
+	proc.argv = argv;
+	proc.in = -1;
+	proc.stdout_to_stderr = 1;
+
+	if (use_sideband) {
+		memset(&muxer, 0, sizeof(muxer));
+		muxer.proc = copy_to_sideband;
+		muxer.in = -1;
+		code = start_async(&muxer);
+		if (code)
+			return code;
+		proc.err = muxer.in;
+	}
+
+	code = start_command(&proc);
+	if (code) {
+		if (use_sideband)
+			finish_async(&muxer);
+		return code;
+	}
+
+	for (cmd = commands; cmd; cmd = cmd->next) {
+		if (!cmd->error_string) {
+			size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
+				sha1_to_hex(cmd->old_sha1),
+				sha1_to_hex(cmd->new_sha1),
+				cmd->ref_name);
+			if (write_in_full(proc.in, buf, n) != n)
+				break;
+		}
+	}
+	close(proc.in);
+	if (use_sideband)
+		finish_async(&muxer);
+	return finish_command(&proc);
+}
+
+static int run_update_hook(struct command *cmd)
+{
+	static const char update_hook[] = "hooks/update";
+	const char *argv[5];
+	struct child_process proc;
+	int code;
+
+	if (access(update_hook, X_OK) < 0)
+		return 0;
+
+	argv[0] = update_hook;
+	argv[1] = cmd->ref_name;
+	argv[2] = sha1_to_hex(cmd->old_sha1);
+	argv[3] = sha1_to_hex(cmd->new_sha1);
+	argv[4] = NULL;
+
+	memset(&proc, 0, sizeof(proc));
+	proc.no_stdin = 1;
+	proc.stdout_to_stderr = 1;
+	proc.err = use_sideband ? -1 : 0;
+	proc.argv = argv;
+
+	code = start_command(&proc);
+	if (code)
+		return code;
+	if (use_sideband)
+		copy_to_sideband(proc.err, -1, NULL);
+	return finish_command(&proc);
+}
+
+static int is_ref_checked_out(const char *ref)
+{
+	if (is_bare_repository())
+		return 0;
+
+	if (!head_name)
+		return 0;
+	return !strcmp(head_name, ref);
+}
+
+static char *refuse_unconfigured_deny_msg[] = {
+	"By default, updating the current branch in a non-bare repository",
+	"is denied, because it will make the index and work tree inconsistent",
+	"with what you pushed, and will require 'git reset --hard' to match",
+	"the work tree to HEAD.",
+	"",
+	"You can set 'receive.denyCurrentBranch' configuration variable to",
+	"'ignore' or 'warn' in the remote repository to allow pushing into",
+	"its current branch; however, this is not recommended unless you",
+	"arranged to update its work tree to match what you pushed in some",
+	"other way.",
+	"",
+	"To squelch this message and still keep the default behaviour, set",
+	"'receive.denyCurrentBranch' configuration variable to 'refuse'."
+};
+
+static void refuse_unconfigured_deny(void)
+{
+	int i;
+	for (i = 0; i < ARRAY_SIZE(refuse_unconfigured_deny_msg); i++)
+		rp_error("%s", refuse_unconfigured_deny_msg[i]);
+}
+
+static char *refuse_unconfigured_deny_delete_current_msg[] = {
+	"By default, deleting the current branch is denied, because the next",
+	"'git clone' won't result in any file checked out, causing confusion.",
+	"",
+	"You can set 'receive.denyDeleteCurrent' configuration variable to",
+	"'warn' or 'ignore' in the remote repository to allow deleting the",
+	"current branch, with or without a warning message.",
+	"",
+	"To squelch this message, you can set it to 'refuse'."
+};
+
+static void refuse_unconfigured_deny_delete_current(void)
+{
+	int i;
+	for (i = 0;
+	     i < ARRAY_SIZE(refuse_unconfigured_deny_delete_current_msg);
+	     i++)
+		rp_error("%s", refuse_unconfigured_deny_delete_current_msg[i]);
+}
+
+static const char *update(struct command *cmd)
+{
+	const char *name = cmd->ref_name;
+	unsigned char *old_sha1 = cmd->old_sha1;
+	unsigned char *new_sha1 = cmd->new_sha1;
+	struct ref_lock *lock;
+
+	/* only refs/... are allowed */
+	if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
+		rp_error("refusing to create funny ref '%s' remotely", name);
+		return "funny refname";
+	}
+
+	if (is_ref_checked_out(name)) {
+		switch (deny_current_branch) {
+		case DENY_IGNORE:
+			break;
+		case DENY_WARN:
+			rp_warning("updating the current branch");
+			break;
+		case DENY_REFUSE:
+		case DENY_UNCONFIGURED:
+			rp_error("refusing to update checked out branch: %s", name);
+			if (deny_current_branch == DENY_UNCONFIGURED)
+				refuse_unconfigured_deny();
+			return "branch is currently checked out";
+		}
+	}
+
+	if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
+		error("unpack should have generated %s, "
+		      "but I can't find it!", sha1_to_hex(new_sha1));
+		return "bad pack";
+	}
+
+	if (!is_null_sha1(old_sha1) && is_null_sha1(new_sha1)) {
+		if (deny_deletes && !prefixcmp(name, "refs/heads/")) {
+			rp_error("denying ref deletion for %s", name);
+			return "deletion prohibited";
+		}
+
+		if (!strcmp(name, head_name)) {
+			switch (deny_delete_current) {
+			case DENY_IGNORE:
+				break;
+			case DENY_WARN:
+				rp_warning("deleting the current branch");
+				break;
+			case DENY_REFUSE:
+			case DENY_UNCONFIGURED:
+				if (deny_delete_current == DENY_UNCONFIGURED)
+					refuse_unconfigured_deny_delete_current();
+				rp_error("refusing to delete the current branch: %s", name);
+				return "deletion of the current branch prohibited";
+			}
+		}
+	}
+
+	if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
+	    !is_null_sha1(old_sha1) &&
+	    !prefixcmp(name, "refs/heads/")) {
+		struct object *old_object, *new_object;
+		struct commit *old_commit, *new_commit;
+		struct commit_list *bases, *ent;
+
+		old_object = parse_object(old_sha1);
+		new_object = parse_object(new_sha1);
+
+		if (!old_object || !new_object ||
+		    old_object->type != OBJ_COMMIT ||
+		    new_object->type != OBJ_COMMIT) {
+			error("bad sha1 objects for %s", name);
+			return "bad ref";
+		}
+		old_commit = (struct commit *)old_object;
+		new_commit = (struct commit *)new_object;
+		bases = get_merge_bases(old_commit, new_commit, 1);
+		for (ent = bases; ent; ent = ent->next)
+			if (!hashcmp(old_sha1, ent->item->object.sha1))
+				break;
+		free_commit_list(bases);
+		if (!ent) {
+			rp_error("denying non-fast-forward %s"
+				 " (you should pull first)", name);
+			return "non-fast-forward";
+		}
+	}
+	if (run_update_hook(cmd)) {
+		rp_error("hook declined to update %s", name);
+		return "hook declined";
+	}
+
+	if (is_null_sha1(new_sha1)) {
+		if (!parse_object(old_sha1)) {
+			rp_warning("Allowing deletion of corrupt ref.");
+			old_sha1 = NULL;
+		}
+		if (delete_ref(name, old_sha1, 0)) {
+			rp_error("failed to delete %s", name);
+			return "failed to delete";
+		}
+		return NULL; /* good */
+	}
+	else {
+		lock = lock_any_ref_for_update(name, old_sha1, 0);
+		if (!lock) {
+			rp_error("failed to lock %s", name);
+			return "failed to lock";
+		}
+		if (write_ref_sha1(lock, new_sha1, "push")) {
+			return "failed to write"; /* error() already called */
+		}
+		return NULL; /* good */
+	}
+}
+
+static char update_post_hook[] = "hooks/post-update";
+
+static void run_update_post_hook(struct command *cmd)
+{
+	struct command *cmd_p;
+	int argc;
+	const char **argv;
+	struct child_process proc;
+
+	for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
+		if (cmd_p->error_string)
+			continue;
+		argc++;
+	}
+	if (!argc || access(update_post_hook, X_OK) < 0)
+		return;
+	argv = xmalloc(sizeof(*argv) * (2 + argc));
+	argv[0] = update_post_hook;
+
+	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
+		char *p;
+		if (cmd_p->error_string)
+			continue;
+		p = xmalloc(strlen(cmd_p->ref_name) + 1);
+		strcpy(p, cmd_p->ref_name);
+		argv[argc] = p;
+		argc++;
+	}
+	argv[argc] = NULL;
+
+	memset(&proc, 0, sizeof(proc));
+	proc.no_stdin = 1;
+	proc.stdout_to_stderr = 1;
+	proc.err = use_sideband ? -1 : 0;
+	proc.argv = argv;
+
+	if (!start_command(&proc)) {
+		if (use_sideband)
+			copy_to_sideband(proc.err, -1, NULL);
+		finish_command(&proc);
+	}
+}
+
+static void execute_commands(const char *unpacker_error)
+{
+	struct command *cmd = commands;
+	unsigned char sha1[20];
+
+	if (unpacker_error) {
+		while (cmd) {
+			cmd->error_string = "n/a (unpacker error)";
+			cmd = cmd->next;
+		}
+		return;
+	}
+
+	if (run_receive_hook(pre_receive_hook)) {
+		while (cmd) {
+			cmd->error_string = "pre-receive hook declined";
+			cmd = cmd->next;
+		}
+		return;
+	}
+
+	head_name = resolve_ref("HEAD", sha1, 0, NULL);
+
+	while (cmd) {
+		cmd->error_string = update(cmd);
+		cmd = cmd->next;
+	}
+}
+
+static void read_head_info(void)
+{
+	struct command **p = &commands;
+	for (;;) {
+		static char line[1000];
+		unsigned char old_sha1[20], new_sha1[20];
+		struct command *cmd;
+		char *refname;
+		int len, reflen;
+
+		len = packet_read_line(0, line, sizeof(line));
+		if (!len)
+			break;
+		if (line[len-1] == '\n')
+			line[--len] = 0;
+		if (len < 83 ||
+		    line[40] != ' ' ||
+		    line[81] != ' ' ||
+		    get_sha1_hex(line, old_sha1) ||
+		    get_sha1_hex(line + 41, new_sha1))
+			die("protocol error: expected old/new/ref, got '%s'",
+			    line);
+
+		refname = line + 82;
+		reflen = strlen(refname);
+		if (reflen + 82 < len) {
+			if (strstr(refname + reflen + 1, "report-status"))
+				report_status = 1;
+			if (strstr(refname + reflen + 1, "side-band-64k"))
+				use_sideband = LARGE_PACKET_MAX;
+		}
+		cmd = xmalloc(sizeof(struct command) + len - 80);
+		hashcpy(cmd->old_sha1, old_sha1);
+		hashcpy(cmd->new_sha1, new_sha1);
+		memcpy(cmd->ref_name, line + 82, len - 81);
+		cmd->error_string = NULL;
+		cmd->next = NULL;
+		*p = cmd;
+		p = &cmd->next;
+	}
+}
+
+static const char *parse_pack_header(struct pack_header *hdr)
+{
+	switch (read_pack_header(0, hdr)) {
+	case PH_ERROR_EOF:
+		return "eof before pack header was fully read";
+
+	case PH_ERROR_PACK_SIGNATURE:
+		return "protocol error (pack signature mismatch detected)";
+
+	case PH_ERROR_PROTOCOL:
+		return "protocol error (pack version unsupported)";
+
+	default:
+		return "unknown error in parse_pack_header";
+
+	case 0:
+		return NULL;
+	}
+}
+
+static const char *pack_lockfile;
+
+static const char *unpack(void)
+{
+	struct pack_header hdr;
+	const char *hdr_err;
+	char hdr_arg[38];
+
+	hdr_err = parse_pack_header(&hdr);
+	if (hdr_err)
+		return hdr_err;
+	snprintf(hdr_arg, sizeof(hdr_arg),
+			"--pack_header=%"PRIu32",%"PRIu32,
+			ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
+
+	if (ntohl(hdr.hdr_entries) < unpack_limit) {
+		int code, i = 0;
+		const char *unpacker[4];
+		unpacker[i++] = "unpack-objects";
+		if (receive_fsck_objects)
+			unpacker[i++] = "--strict";
+		unpacker[i++] = hdr_arg;
+		unpacker[i++] = NULL;
+		code = run_command_v_opt(unpacker, RUN_GIT_CMD);
+		if (!code)
+			return NULL;
+		return "unpack-objects abnormal exit";
+	} else {
+		const char *keeper[7];
+		int s, status, i = 0;
+		char keep_arg[256];
+		struct child_process ip;
+
+		s = sprintf(keep_arg, "--keep=receive-pack %"PRIuMAX" on ", (uintmax_t) getpid());
+		if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
+			strcpy(keep_arg + s, "localhost");
+
+		keeper[i++] = "index-pack";
+		keeper[i++] = "--stdin";
+		if (receive_fsck_objects)
+			keeper[i++] = "--strict";
+		keeper[i++] = "--fix-thin";
+		keeper[i++] = hdr_arg;
+		keeper[i++] = keep_arg;
+		keeper[i++] = NULL;
+		memset(&ip, 0, sizeof(ip));
+		ip.argv = keeper;
+		ip.out = -1;
+		ip.git_cmd = 1;
+		status = start_command(&ip);
+		if (status) {
+			return "index-pack fork failed";
+		}
+		pack_lockfile = index_pack_lockfile(ip.out);
+		close(ip.out);
+		status = finish_command(&ip);
+		if (!status) {
+			reprepare_packed_git();
+			return NULL;
+		}
+		return "index-pack abnormal exit";
+	}
+}
+
+static void report(const char *unpack_status)
+{
+	struct command *cmd;
+	struct strbuf buf = STRBUF_INIT;
+
+	packet_buf_write(&buf, "unpack %s\n",
+			 unpack_status ? unpack_status : "ok");
+	for (cmd = commands; cmd; cmd = cmd->next) {
+		if (!cmd->error_string)
+			packet_buf_write(&buf, "ok %s\n",
+					 cmd->ref_name);
+		else
+			packet_buf_write(&buf, "ng %s %s\n",
+					 cmd->ref_name, cmd->error_string);
+	}
+	packet_buf_flush(&buf);
+
+	if (use_sideband)
+		send_sideband(1, 1, buf.buf, buf.len, use_sideband);
+	else
+		safe_write(1, buf.buf, buf.len);
+	strbuf_release(&buf);
+}
+
+static int delete_only(struct command *cmd)
+{
+	while (cmd) {
+		if (!is_null_sha1(cmd->new_sha1))
+			return 0;
+		cmd = cmd->next;
+	}
+	return 1;
+}
+
+static int add_refs_from_alternate(struct alternate_object_database *e, void *unused)
+{
+	char *other;
+	size_t len;
+	struct remote *remote;
+	struct transport *transport;
+	const struct ref *extra;
+
+	e->name[-1] = '\0';
+	other = xstrdup(make_absolute_path(e->base));
+	e->name[-1] = '/';
+	len = strlen(other);
+
+	while (other[len-1] == '/')
+		other[--len] = '\0';
+	if (len < 8 || memcmp(other + len - 8, "/objects", 8))
+		return 0;
+	/* Is this a git repository with refs? */
+	memcpy(other + len - 8, "/refs", 6);
+	if (!is_directory(other))
+		return 0;
+	other[len - 8] = '\0';
+	remote = remote_get(other);
+	transport = transport_get(remote, other);
+	for (extra = transport_get_remote_refs(transport);
+	     extra;
+	     extra = extra->next) {
+		add_extra_ref(".have", extra->old_sha1, 0);
+	}
+	transport_disconnect(transport);
+	free(other);
+	return 0;
+}
+
+static void add_alternate_refs(void)
+{
+	foreach_alt_odb(add_refs_from_alternate, NULL);
+}
+
+int cmd_receive_pack(int argc, const char **argv, const char *prefix)
+{
+	int advertise_refs = 0;
+	int stateless_rpc = 0;
+	int i;
+	char *dir = NULL;
+
+	argv++;
+	for (i = 1; i < argc; i++) {
+		const char *arg = *argv++;
+
+		if (*arg == '-') {
+			if (!strcmp(arg, "--advertise-refs")) {
+				advertise_refs = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--stateless-rpc")) {
+				stateless_rpc = 1;
+				continue;
+			}
+
+			usage(receive_pack_usage);
+		}
+		if (dir)
+			usage(receive_pack_usage);
+		dir = xstrdup(arg);
+	}
+	if (!dir)
+		usage(receive_pack_usage);
+
+	setup_path();
+
+	if (!enter_repo(dir, 0))
+		die("'%s' does not appear to be a git repository", dir);
+
+	if (is_repository_shallow())
+		die("attempt to push into a shallow repository");
+
+	git_config(receive_pack_config, NULL);
+
+	if (0 <= transfer_unpack_limit)
+		unpack_limit = transfer_unpack_limit;
+	else if (0 <= receive_unpack_limit)
+		unpack_limit = receive_unpack_limit;
+
+	if (advertise_refs || !stateless_rpc) {
+		add_alternate_refs();
+		write_head_info();
+		clear_extra_refs();
+
+		/* EOF */
+		packet_flush(1);
+	}
+	if (advertise_refs)
+		return 0;
+
+	read_head_info();
+	if (commands) {
+		const char *unpack_status = NULL;
+
+		if (!delete_only(commands))
+			unpack_status = unpack();
+		execute_commands(unpack_status);
+		if (pack_lockfile)
+			unlink_or_warn(pack_lockfile);
+		if (report_status)
+			report(unpack_status);
+		run_receive_hook(post_receive_hook);
+		run_update_post_hook(commands);
+		if (auto_gc) {
+			const char *argv_gc_auto[] = {
+				"gc", "--auto", "--quiet", NULL,
+			};
+			run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
+		}
+		if (auto_update_server_info)
+			update_server_info(0);
+	}
+	if (use_sideband)
+		packet_flush(1);
+	return 0;
+}
diff --git a/builtin/reflog.c b/builtin/reflog.c
new file mode 100644
index 0000000..64e45bd
--- /dev/null
+++ b/builtin/reflog.c
@@ -0,0 +1,717 @@
+#include "cache.h"
+#include "builtin.h"
+#include "commit.h"
+#include "refs.h"
+#include "dir.h"
+#include "tree-walk.h"
+#include "diff.h"
+#include "revision.h"
+#include "reachable.h"
+
+/*
+ * reflog expire
+ */
+
+static const char reflog_expire_usage[] =
+"git reflog (show|expire) [--verbose] [--dry-run] [--stale-fix] [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...";
+static const char reflog_delete_usage[] =
+"git reflog delete [--verbose] [--dry-run] [--rewrite] [--updateref] <refs>...";
+
+static unsigned long default_reflog_expire;
+static unsigned long default_reflog_expire_unreachable;
+
+struct cmd_reflog_expire_cb {
+	struct rev_info revs;
+	int dry_run;
+	int stalefix;
+	int rewrite;
+	int updateref;
+	int verbose;
+	unsigned long expire_total;
+	unsigned long expire_unreachable;
+	int recno;
+};
+
+struct expire_reflog_cb {
+	FILE *newlog;
+	const char *ref;
+	struct commit *ref_commit;
+	struct cmd_reflog_expire_cb *cmd;
+	unsigned char last_kept_sha1[20];
+};
+
+struct collected_reflog {
+	unsigned char sha1[20];
+	char reflog[FLEX_ARRAY];
+};
+struct collect_reflog_cb {
+	struct collected_reflog **e;
+	int alloc;
+	int nr;
+};
+
+#define INCOMPLETE	(1u<<10)
+#define STUDYING	(1u<<11)
+#define REACHABLE	(1u<<12)
+
+static int tree_is_complete(const unsigned char *sha1)
+{
+	struct tree_desc desc;
+	struct name_entry entry;
+	int complete;
+	struct tree *tree;
+
+	tree = lookup_tree(sha1);
+	if (!tree)
+		return 0;
+	if (tree->object.flags & SEEN)
+		return 1;
+	if (tree->object.flags & INCOMPLETE)
+		return 0;
+
+	if (!tree->buffer) {
+		enum object_type type;
+		unsigned long size;
+		void *data = read_sha1_file(sha1, &type, &size);
+		if (!data) {
+			tree->object.flags |= INCOMPLETE;
+			return 0;
+		}
+		tree->buffer = data;
+		tree->size = size;
+	}
+	init_tree_desc(&desc, tree->buffer, tree->size);
+	complete = 1;
+	while (tree_entry(&desc, &entry)) {
+		if (!has_sha1_file(entry.sha1) ||
+		    (S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
+			tree->object.flags |= INCOMPLETE;
+			complete = 0;
+		}
+	}
+	free(tree->buffer);
+	tree->buffer = NULL;
+
+	if (complete)
+		tree->object.flags |= SEEN;
+	return complete;
+}
+
+static int commit_is_complete(struct commit *commit)
+{
+	struct object_array study;
+	struct object_array found;
+	int is_incomplete = 0;
+	int i;
+
+	/* early return */
+	if (commit->object.flags & SEEN)
+		return 1;
+	if (commit->object.flags & INCOMPLETE)
+		return 0;
+	/*
+	 * Find all commits that are reachable and are not marked as
+	 * SEEN.  Then make sure the trees and blobs contained are
+	 * complete.  After that, mark these commits also as SEEN.
+	 * If some of the objects that are needed to complete this
+	 * commit are missing, mark this commit as INCOMPLETE.
+	 */
+	memset(&study, 0, sizeof(study));
+	memset(&found, 0, sizeof(found));
+	add_object_array(&commit->object, NULL, &study);
+	add_object_array(&commit->object, NULL, &found);
+	commit->object.flags |= STUDYING;
+	while (study.nr) {
+		struct commit *c;
+		struct commit_list *parent;
+
+		c = (struct commit *)study.objects[--study.nr].item;
+		if (!c->object.parsed && !parse_object(c->object.sha1))
+			c->object.flags |= INCOMPLETE;
+
+		if (c->object.flags & INCOMPLETE) {
+			is_incomplete = 1;
+			break;
+		}
+		else if (c->object.flags & SEEN)
+			continue;
+		for (parent = c->parents; parent; parent = parent->next) {
+			struct commit *p = parent->item;
+			if (p->object.flags & STUDYING)
+				continue;
+			p->object.flags |= STUDYING;
+			add_object_array(&p->object, NULL, &study);
+			add_object_array(&p->object, NULL, &found);
+		}
+	}
+	if (!is_incomplete) {
+		/*
+		 * make sure all commits in "found" array have all the
+		 * necessary objects.
+		 */
+		for (i = 0; i < found.nr; i++) {
+			struct commit *c =
+				(struct commit *)found.objects[i].item;
+			if (!tree_is_complete(c->tree->object.sha1)) {
+				is_incomplete = 1;
+				c->object.flags |= INCOMPLETE;
+			}
+		}
+		if (!is_incomplete) {
+			/* mark all found commits as complete, iow SEEN */
+			for (i = 0; i < found.nr; i++)
+				found.objects[i].item->flags |= SEEN;
+		}
+	}
+	/* clear flags from the objects we traversed */
+	for (i = 0; i < found.nr; i++)
+		found.objects[i].item->flags &= ~STUDYING;
+	if (is_incomplete)
+		commit->object.flags |= INCOMPLETE;
+	else {
+		/*
+		 * If we come here, we have (1) traversed the ancestry chain
+		 * from the "commit" until we reach SEEN commits (which are
+		 * known to be complete), and (2) made sure that the commits
+		 * encountered during the above traversal refer to trees that
+		 * are complete.  Which means that we know *all* the commits
+		 * we have seen during this process are complete.
+		 */
+		for (i = 0; i < found.nr; i++)
+			found.objects[i].item->flags |= SEEN;
+	}
+	/* free object arrays */
+	free(study.objects);
+	free(found.objects);
+	return !is_incomplete;
+}
+
+static int keep_entry(struct commit **it, unsigned char *sha1)
+{
+	struct commit *commit;
+
+	if (is_null_sha1(sha1))
+		return 1;
+	commit = lookup_commit_reference_gently(sha1, 1);
+	if (!commit)
+		return 0;
+
+	/*
+	 * Make sure everything in this commit exists.
+	 *
+	 * We have walked all the objects reachable from the refs
+	 * and cache earlier.  The commits reachable by this commit
+	 * must meet SEEN commits -- and then we should mark them as
+	 * SEEN as well.
+	 */
+	if (!commit_is_complete(commit))
+		return 0;
+	*it = commit;
+	return 1;
+}
+
+static int unreachable(struct expire_reflog_cb *cb, struct commit *commit, unsigned char *sha1)
+{
+	/*
+	 * We may or may not have the commit yet - if not, look it
+	 * up using the supplied sha1.
+	 */
+	if (!commit) {
+		if (is_null_sha1(sha1))
+			return 0;
+
+		commit = lookup_commit_reference_gently(sha1, 1);
+
+		/* Not a commit -- keep it */
+		if (!commit)
+			return 0;
+	}
+
+	/* Reachable from the current ref?  Don't prune. */
+	if (commit->object.flags & REACHABLE)
+		return 0;
+	if (in_merge_bases(commit, &cb->ref_commit, 1))
+		return 0;
+
+	/* We can't reach it - prune it. */
+	return 1;
+}
+
+static void mark_reachable(struct commit *commit, unsigned long expire_limit)
+{
+	/*
+	 * We need to compute whether the commit on either side of a reflog
+	 * entry is reachable from the tip of the ref for all entries.
+	 * Mark commits that are reachable from the tip down to the
+	 * time threshold first; we know a commit marked thusly is
+	 * reachable from the tip without running in_merge_bases()
+	 * at all.
+	 */
+	struct commit_list *pending = NULL;
+
+	commit_list_insert(commit, &pending);
+	while (pending) {
+		struct commit_list *entry = pending;
+		struct commit_list *parent;
+		pending = entry->next;
+		commit = entry->item;
+		free(entry);
+		if (commit->object.flags & REACHABLE)
+			continue;
+		if (parse_commit(commit))
+			continue;
+		commit->object.flags |= REACHABLE;
+		if (commit->date < expire_limit)
+			continue;
+		parent = commit->parents;
+		while (parent) {
+			commit = parent->item;
+			parent = parent->next;
+			if (commit->object.flags & REACHABLE)
+				continue;
+			commit_list_insert(commit, &pending);
+		}
+	}
+}
+
+static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
+		const char *email, unsigned long timestamp, int tz,
+		const char *message, void *cb_data)
+{
+	struct expire_reflog_cb *cb = cb_data;
+	struct commit *old, *new;
+
+	if (timestamp < cb->cmd->expire_total)
+		goto prune;
+
+	if (cb->cmd->rewrite)
+		osha1 = cb->last_kept_sha1;
+
+	old = new = NULL;
+	if (cb->cmd->stalefix &&
+	    (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
+		goto prune;
+
+	if (timestamp < cb->cmd->expire_unreachable) {
+		if (!cb->ref_commit)
+			goto prune;
+		if (unreachable(cb, old, osha1) || unreachable(cb, new, nsha1))
+			goto prune;
+	}
+
+	if (cb->cmd->recno && --(cb->cmd->recno) == 0)
+		goto prune;
+
+	if (cb->newlog) {
+		char sign = (tz < 0) ? '-' : '+';
+		int zone = (tz < 0) ? (-tz) : tz;
+		fprintf(cb->newlog, "%s %s %s %lu %c%04d\t%s",
+			sha1_to_hex(osha1), sha1_to_hex(nsha1),
+			email, timestamp, sign, zone,
+			message);
+		hashcpy(cb->last_kept_sha1, nsha1);
+	}
+	if (cb->cmd->verbose)
+		printf("keep %s", message);
+	return 0;
+ prune:
+	if (!cb->newlog || cb->cmd->verbose)
+		printf("%sprune %s", cb->newlog ? "" : "would ", message);
+	return 0;
+}
+
+static int expire_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
+{
+	struct cmd_reflog_expire_cb *cmd = cb_data;
+	struct expire_reflog_cb cb;
+	struct ref_lock *lock;
+	char *log_file, *newlog_path = NULL;
+	int status = 0;
+
+	memset(&cb, 0, sizeof(cb));
+
+	/*
+	 * we take the lock for the ref itself to prevent it from
+	 * getting updated.
+	 */
+	lock = lock_any_ref_for_update(ref, sha1, 0);
+	if (!lock)
+		return error("cannot lock ref '%s'", ref);
+	log_file = git_pathdup("logs/%s", ref);
+	if (!file_exists(log_file))
+		goto finish;
+	if (!cmd->dry_run) {
+		newlog_path = git_pathdup("logs/%s.lock", ref);
+		cb.newlog = fopen(newlog_path, "w");
+	}
+
+	cb.ref_commit = lookup_commit_reference_gently(sha1, 1);
+	cb.ref = ref;
+	cb.cmd = cmd;
+	if (cb.ref_commit)
+		mark_reachable(cb.ref_commit, cmd->expire_total);
+	for_each_reflog_ent(ref, expire_reflog_ent, &cb);
+	if (cb.ref_commit)
+		clear_commit_marks(cb.ref_commit, REACHABLE);
+ finish:
+	if (cb.newlog) {
+		if (fclose(cb.newlog)) {
+			status |= error("%s: %s", strerror(errno),
+					newlog_path);
+			unlink(newlog_path);
+		} else if (cmd->updateref &&
+			(write_in_full(lock->lock_fd,
+				sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
+			 write_str_in_full(lock->lock_fd, "\n") != 1 ||
+			 close_ref(lock) < 0)) {
+			status |= error("Couldn't write %s",
+				lock->lk->filename);
+			unlink(newlog_path);
+		} else if (rename(newlog_path, log_file)) {
+			status |= error("cannot rename %s to %s",
+					newlog_path, log_file);
+			unlink(newlog_path);
+		} else if (cmd->updateref && commit_ref(lock)) {
+			status |= error("Couldn't set %s", lock->ref_name);
+		} else {
+			adjust_shared_perm(log_file);
+		}
+	}
+	free(newlog_path);
+	free(log_file);
+	unlock_ref(lock);
+	return status;
+}
+
+static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
+{
+	struct collected_reflog *e;
+	struct collect_reflog_cb *cb = cb_data;
+	size_t namelen = strlen(ref);
+
+	e = xmalloc(sizeof(*e) + namelen + 1);
+	hashcpy(e->sha1, sha1);
+	memcpy(e->reflog, ref, namelen + 1);
+	ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
+	cb->e[cb->nr++] = e;
+	return 0;
+}
+
+static struct reflog_expire_cfg {
+	struct reflog_expire_cfg *next;
+	unsigned long expire_total;
+	unsigned long expire_unreachable;
+	size_t len;
+	char pattern[FLEX_ARRAY];
+} *reflog_expire_cfg, **reflog_expire_cfg_tail;
+
+static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
+{
+	struct reflog_expire_cfg *ent;
+
+	if (!reflog_expire_cfg_tail)
+		reflog_expire_cfg_tail = &reflog_expire_cfg;
+
+	for (ent = reflog_expire_cfg; ent; ent = ent->next)
+		if (ent->len == len &&
+		    !memcmp(ent->pattern, pattern, len))
+			return ent;
+
+	ent = xcalloc(1, (sizeof(*ent) + len));
+	memcpy(ent->pattern, pattern, len);
+	ent->len = len;
+	*reflog_expire_cfg_tail = ent;
+	reflog_expire_cfg_tail = &(ent->next);
+	return ent;
+}
+
+static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
+{
+	if (!value)
+		return config_error_nonbool(var);
+	if (!strcmp(value, "never") || !strcmp(value, "false")) {
+		*expire = 0;
+		return 0;
+	}
+	*expire = approxidate(value);
+	return 0;
+}
+
+/* expiry timer slot */
+#define EXPIRE_TOTAL   01
+#define EXPIRE_UNREACH 02
+
+static int reflog_expire_config(const char *var, const char *value, void *cb)
+{
+	const char *lastdot = strrchr(var, '.');
+	unsigned long expire;
+	int slot;
+	struct reflog_expire_cfg *ent;
+
+	if (!lastdot || prefixcmp(var, "gc."))
+		return git_default_config(var, value, cb);
+
+	if (!strcmp(lastdot, ".reflogexpire")) {
+		slot = EXPIRE_TOTAL;
+		if (parse_expire_cfg_value(var, value, &expire))
+			return -1;
+	} else if (!strcmp(lastdot, ".reflogexpireunreachable")) {
+		slot = EXPIRE_UNREACH;
+		if (parse_expire_cfg_value(var, value, &expire))
+			return -1;
+	} else
+		return git_default_config(var, value, cb);
+
+	if (lastdot == var + 2) {
+		switch (slot) {
+		case EXPIRE_TOTAL:
+			default_reflog_expire = expire;
+			break;
+		case EXPIRE_UNREACH:
+			default_reflog_expire_unreachable = expire;
+			break;
+		}
+		return 0;
+	}
+
+	ent = find_cfg_ent(var + 3, lastdot - (var+3));
+	if (!ent)
+		return -1;
+	switch (slot) {
+	case EXPIRE_TOTAL:
+		ent->expire_total = expire;
+		break;
+	case EXPIRE_UNREACH:
+		ent->expire_unreachable = expire;
+		break;
+	}
+	return 0;
+}
+
+static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
+{
+	struct reflog_expire_cfg *ent;
+
+	if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
+		return; /* both given explicitly -- nothing to tweak */
+
+	for (ent = reflog_expire_cfg; ent; ent = ent->next) {
+		if (!fnmatch(ent->pattern, ref, 0)) {
+			if (!(slot & EXPIRE_TOTAL))
+				cb->expire_total = ent->expire_total;
+			if (!(slot & EXPIRE_UNREACH))
+				cb->expire_unreachable = ent->expire_unreachable;
+			return;
+		}
+	}
+
+	/*
+	 * If unconfigured, make stash never expire
+	 */
+	if (!strcmp(ref, "refs/stash")) {
+		if (!(slot & EXPIRE_TOTAL))
+			cb->expire_total = 0;
+		if (!(slot & EXPIRE_UNREACH))
+			cb->expire_unreachable = 0;
+		return;
+	}
+
+	/* Nothing matched -- use the default value */
+	if (!(slot & EXPIRE_TOTAL))
+		cb->expire_total = default_reflog_expire;
+	if (!(slot & EXPIRE_UNREACH))
+		cb->expire_unreachable = default_reflog_expire_unreachable;
+}
+
+static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
+{
+	struct cmd_reflog_expire_cb cb;
+	unsigned long now = time(NULL);
+	int i, status, do_all;
+	int explicit_expiry = 0;
+
+	default_reflog_expire_unreachable = now - 30 * 24 * 3600;
+	default_reflog_expire = now - 90 * 24 * 3600;
+	git_config(reflog_expire_config, NULL);
+
+	save_commit_buffer = 0;
+	do_all = status = 0;
+	memset(&cb, 0, sizeof(cb));
+
+	cb.expire_total = default_reflog_expire;
+	cb.expire_unreachable = default_reflog_expire_unreachable;
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
+			cb.dry_run = 1;
+		else if (!prefixcmp(arg, "--expire=")) {
+			cb.expire_total = approxidate(arg + 9);
+			explicit_expiry |= EXPIRE_TOTAL;
+		}
+		else if (!prefixcmp(arg, "--expire-unreachable=")) {
+			cb.expire_unreachable = approxidate(arg + 21);
+			explicit_expiry |= EXPIRE_UNREACH;
+		}
+		else if (!strcmp(arg, "--stale-fix"))
+			cb.stalefix = 1;
+		else if (!strcmp(arg, "--rewrite"))
+			cb.rewrite = 1;
+		else if (!strcmp(arg, "--updateref"))
+			cb.updateref = 1;
+		else if (!strcmp(arg, "--all"))
+			do_all = 1;
+		else if (!strcmp(arg, "--verbose"))
+			cb.verbose = 1;
+		else if (!strcmp(arg, "--")) {
+			i++;
+			break;
+		}
+		else if (arg[0] == '-')
+			usage(reflog_expire_usage);
+		else
+			break;
+	}
+
+	/*
+	 * We can trust the commits and objects reachable from refs
+	 * even in older repository.  We cannot trust what's reachable
+	 * from reflog if the repository was pruned with older git.
+	 */
+	if (cb.stalefix) {
+		init_revisions(&cb.revs, prefix);
+		if (cb.verbose)
+			printf("Marking reachable objects...");
+		mark_reachable_objects(&cb.revs, 0);
+		if (cb.verbose)
+			putchar('\n');
+	}
+
+	if (do_all) {
+		struct collect_reflog_cb collected;
+		int i;
+
+		memset(&collected, 0, sizeof(collected));
+		for_each_reflog(collect_reflog, &collected);
+		for (i = 0; i < collected.nr; i++) {
+			struct collected_reflog *e = collected.e[i];
+			set_reflog_expiry_param(&cb, explicit_expiry, e->reflog);
+			status |= expire_reflog(e->reflog, e->sha1, 0, &cb);
+			free(e);
+		}
+		free(collected.e);
+	}
+
+	for (; i < argc; i++) {
+		char *ref;
+		unsigned char sha1[20];
+		if (!dwim_log(argv[i], strlen(argv[i]), sha1, &ref)) {
+			status |= error("%s points nowhere!", argv[i]);
+			continue;
+		}
+		set_reflog_expiry_param(&cb, explicit_expiry, ref);
+		status |= expire_reflog(ref, sha1, 0, &cb);
+	}
+	return status;
+}
+
+static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
+		const char *email, unsigned long timestamp, int tz,
+		const char *message, void *cb_data)
+{
+	struct cmd_reflog_expire_cb *cb = cb_data;
+	if (!cb->expire_total || timestamp < cb->expire_total)
+		cb->recno++;
+	return 0;
+}
+
+static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
+{
+	struct cmd_reflog_expire_cb cb;
+	int i, status = 0;
+
+	memset(&cb, 0, sizeof(cb));
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
+			cb.dry_run = 1;
+		else if (!strcmp(arg, "--rewrite"))
+			cb.rewrite = 1;
+		else if (!strcmp(arg, "--updateref"))
+			cb.updateref = 1;
+		else if (!strcmp(arg, "--verbose"))
+			cb.verbose = 1;
+		else if (!strcmp(arg, "--")) {
+			i++;
+			break;
+		}
+		else if (arg[0] == '-')
+			usage(reflog_delete_usage);
+		else
+			break;
+	}
+
+	if (argc - i < 1)
+		return error("Nothing to delete?");
+
+	for ( ; i < argc; i++) {
+		const char *spec = strstr(argv[i], "@{");
+		unsigned char sha1[20];
+		char *ep, *ref;
+		int recno;
+
+		if (!spec) {
+			status |= error("Not a reflog: %s", argv[i]);
+			continue;
+		}
+
+		if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
+			status |= error("no reflog for '%s'", argv[i]);
+			continue;
+		}
+
+		recno = strtoul(spec + 2, &ep, 10);
+		if (*ep == '}') {
+			cb.recno = -recno;
+			for_each_reflog_ent(ref, count_reflog_ent, &cb);
+		} else {
+			cb.expire_total = approxidate(spec + 2);
+			for_each_reflog_ent(ref, count_reflog_ent, &cb);
+			cb.expire_total = 0;
+		}
+
+		status |= expire_reflog(ref, sha1, 0, &cb);
+		free(ref);
+	}
+	return status;
+}
+
+/*
+ * main "reflog"
+ */
+
+static const char reflog_usage[] =
+"git reflog [ show | expire | delete ]";
+
+int cmd_reflog(int argc, const char **argv, const char *prefix)
+{
+	if (argc > 1 && !strcmp(argv[1], "-h"))
+		usage(reflog_usage);
+
+	/* With no command, we default to showing it. */
+	if (argc < 2 || *argv[1] == '-')
+		return cmd_log_reflog(argc, argv, prefix);
+
+	if (!strcmp(argv[1], "show"))
+		return cmd_log_reflog(argc - 1, argv + 1, prefix);
+
+	if (!strcmp(argv[1], "expire"))
+		return cmd_reflog_expire(argc - 1, argv + 1, prefix);
+
+	if (!strcmp(argv[1], "delete"))
+		return cmd_reflog_delete(argc - 1, argv + 1, prefix);
+
+	/* Not a recognized reflog command..*/
+	usage(reflog_usage);
+}
diff --git a/builtin/remote.c b/builtin/remote.c
new file mode 100644
index 0000000..277765b
--- /dev/null
+++ b/builtin/remote.c
@@ -0,0 +1,1447 @@
+#include "cache.h"
+#include "parse-options.h"
+#include "transport.h"
+#include "remote.h"
+#include "string-list.h"
+#include "strbuf.h"
+#include "run-command.h"
+#include "refs.h"
+
+static const char * const builtin_remote_usage[] = {
+	"git remote [-v | --verbose]",
+	"git remote add [-t <branch>] [-m <master>] [-f] [--mirror] <name> <url>",
+	"git remote rename <old> <new>",
+	"git remote rm <name>",
+	"git remote set-head <name> (-a | -d | <branch>)",
+	"git remote [-v | --verbose] show [-n] <name>",
+	"git remote prune [-n | --dry-run] <name>",
+	"git remote [-v | --verbose] update [-p | --prune] [group | remote]",
+	"git remote set-url <name> <newurl> [<oldurl>]",
+	"git remote set-url --add <name> <newurl>",
+	"git remote set-url --delete <name> <url>",
+	NULL
+};
+
+static const char * const builtin_remote_add_usage[] = {
+	"git remote add [<options>] <name> <url>",
+	NULL
+};
+
+static const char * const builtin_remote_rename_usage[] = {
+	"git remote rename <old> <new>",
+	NULL
+};
+
+static const char * const builtin_remote_rm_usage[] = {
+	"git remote rm <name>",
+	NULL
+};
+
+static const char * const builtin_remote_sethead_usage[] = {
+	"git remote set-head <name> (-a | -d | <branch>])",
+	NULL
+};
+
+static const char * const builtin_remote_show_usage[] = {
+	"git remote show [<options>] <name>",
+	NULL
+};
+
+static const char * const builtin_remote_prune_usage[] = {
+	"git remote prune [<options>] <name>",
+	NULL
+};
+
+static const char * const builtin_remote_update_usage[] = {
+	"git remote update [<options>] [<group> | <remote>]...",
+	NULL
+};
+
+static const char * const builtin_remote_seturl_usage[] = {
+	"git remote set-url [--push] <name> <newurl> [<oldurl>]",
+	"git remote set-url --add <name> <newurl>",
+	"git remote set-url --delete <name> <url>",
+	NULL
+};
+
+#define GET_REF_STATES (1<<0)
+#define GET_HEAD_NAMES (1<<1)
+#define GET_PUSH_REF_STATES (1<<2)
+
+static int verbose;
+
+static int show_all(void);
+static int prune_remote(const char *remote, int dry_run);
+
+static inline int postfixcmp(const char *string, const char *postfix)
+{
+	int len1 = strlen(string), len2 = strlen(postfix);
+	if (len1 < len2)
+		return 1;
+	return strcmp(string + len1 - len2, postfix);
+}
+
+static int opt_parse_track(const struct option *opt, const char *arg, int not)
+{
+	struct string_list *list = opt->value;
+	if (not)
+		string_list_clear(list, 0);
+	else
+		string_list_append(arg, list);
+	return 0;
+}
+
+static int fetch_remote(const char *name)
+{
+	const char *argv[] = { "fetch", name, NULL, NULL };
+	if (verbose) {
+		argv[1] = "-v";
+		argv[2] = name;
+	}
+	printf("Updating %s\n", name);
+	if (run_command_v_opt(argv, RUN_GIT_CMD))
+		return error("Could not fetch %s", name);
+	return 0;
+}
+
+static int add(int argc, const char **argv)
+{
+	int fetch = 0, mirror = 0;
+	struct string_list track = { NULL, 0, 0 };
+	const char *master = NULL;
+	struct remote *remote;
+	struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT;
+	const char *name, *url;
+	int i;
+
+	struct option options[] = {
+		OPT_BOOLEAN('f', "fetch", &fetch, "fetch the remote branches"),
+		OPT_CALLBACK('t', "track", &track, "branch",
+			"branch(es) to track", opt_parse_track),
+		OPT_STRING('m', "master", &master, "branch", "master branch"),
+		OPT_BOOLEAN(0, "mirror", &mirror, "no separate remotes"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, NULL, options, builtin_remote_add_usage,
+			     0);
+
+	if (argc < 2)
+		usage_with_options(builtin_remote_add_usage, options);
+
+	name = argv[0];
+	url = argv[1];
+
+	remote = remote_get(name);
+	if (remote && (remote->url_nr > 1 || strcmp(name, remote->url[0]) ||
+			remote->fetch_refspec_nr))
+		die("remote %s already exists.", name);
+
+	strbuf_addf(&buf2, "refs/heads/test:refs/remotes/%s/test", name);
+	if (!valid_fetch_refspec(buf2.buf))
+		die("'%s' is not a valid remote name", name);
+
+	strbuf_addf(&buf, "remote.%s.url", name);
+	if (git_config_set(buf.buf, url))
+		return 1;
+
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "remote.%s.fetch", name);
+
+	if (track.nr == 0)
+		string_list_append("*", &track);
+	for (i = 0; i < track.nr; i++) {
+		struct string_list_item *item = track.items + i;
+
+		strbuf_reset(&buf2);
+		strbuf_addch(&buf2, '+');
+		if (mirror)
+			strbuf_addf(&buf2, "refs/%s:refs/%s",
+					item->string, item->string);
+		else
+			strbuf_addf(&buf2, "refs/heads/%s:refs/remotes/%s/%s",
+					item->string, name, item->string);
+		if (git_config_set_multivar(buf.buf, buf2.buf, "^$", 0))
+			return 1;
+	}
+
+	if (mirror) {
+		strbuf_reset(&buf);
+		strbuf_addf(&buf, "remote.%s.mirror", name);
+		if (git_config_set(buf.buf, "true"))
+			return 1;
+	}
+
+	if (fetch && fetch_remote(name))
+		return 1;
+
+	if (master) {
+		strbuf_reset(&buf);
+		strbuf_addf(&buf, "refs/remotes/%s/HEAD", name);
+
+		strbuf_reset(&buf2);
+		strbuf_addf(&buf2, "refs/remotes/%s/%s", name, master);
+
+		if (create_symref(buf.buf, buf2.buf, "remote add"))
+			return error("Could not setup master '%s'", master);
+	}
+
+	strbuf_release(&buf);
+	strbuf_release(&buf2);
+	string_list_clear(&track, 0);
+
+	return 0;
+}
+
+struct branch_info {
+	char *remote_name;
+	struct string_list merge;
+	int rebase;
+};
+
+static struct string_list branch_list;
+
+static const char *abbrev_ref(const char *name, const char *prefix)
+{
+	const char *abbrev = skip_prefix(name, prefix);
+	if (abbrev)
+		return abbrev;
+	return name;
+}
+#define abbrev_branch(name) abbrev_ref((name), "refs/heads/")
+
+static int config_read_branches(const char *key, const char *value, void *cb)
+{
+	if (!prefixcmp(key, "branch.")) {
+		const char *orig_key = key;
+		char *name;
+		struct string_list_item *item;
+		struct branch_info *info;
+		enum { REMOTE, MERGE, REBASE } type;
+
+		key += 7;
+		if (!postfixcmp(key, ".remote")) {
+			name = xstrndup(key, strlen(key) - 7);
+			type = REMOTE;
+		} else if (!postfixcmp(key, ".merge")) {
+			name = xstrndup(key, strlen(key) - 6);
+			type = MERGE;
+		} else if (!postfixcmp(key, ".rebase")) {
+			name = xstrndup(key, strlen(key) - 7);
+			type = REBASE;
+		} else
+			return 0;
+
+		item = string_list_insert(name, &branch_list);
+
+		if (!item->util)
+			item->util = xcalloc(sizeof(struct branch_info), 1);
+		info = item->util;
+		if (type == REMOTE) {
+			if (info->remote_name)
+				warning("more than one %s", orig_key);
+			info->remote_name = xstrdup(value);
+		} else if (type == MERGE) {
+			char *space = strchr(value, ' ');
+			value = abbrev_branch(value);
+			while (space) {
+				char *merge;
+				merge = xstrndup(value, space - value);
+				string_list_append(merge, &info->merge);
+				value = abbrev_branch(space + 1);
+				space = strchr(value, ' ');
+			}
+			string_list_append(xstrdup(value), &info->merge);
+		} else
+			info->rebase = git_config_bool(orig_key, value);
+	}
+	return 0;
+}
+
+static void read_branches(void)
+{
+	if (branch_list.nr)
+		return;
+	git_config(config_read_branches, NULL);
+}
+
+struct ref_states {
+	struct remote *remote;
+	struct string_list new, stale, tracked, heads, push;
+	int queried;
+};
+
+static int get_ref_states(const struct ref *remote_refs, struct ref_states *states)
+{
+	struct ref *fetch_map = NULL, **tail = &fetch_map;
+	struct ref *ref, *stale_refs;
+	int i;
+
+	for (i = 0; i < states->remote->fetch_refspec_nr; i++)
+		if (get_fetch_map(remote_refs, states->remote->fetch + i, &tail, 1))
+			die("Could not get fetch map for refspec %s",
+				states->remote->fetch_refspec[i]);
+
+	states->new.strdup_strings = 1;
+	states->tracked.strdup_strings = 1;
+	states->stale.strdup_strings = 1;
+	for (ref = fetch_map; ref; ref = ref->next) {
+		unsigned char sha1[20];
+		if (!ref->peer_ref || read_ref(ref->peer_ref->name, sha1))
+			string_list_append(abbrev_branch(ref->name), &states->new);
+		else
+			string_list_append(abbrev_branch(ref->name), &states->tracked);
+	}
+	stale_refs = get_stale_heads(states->remote, fetch_map);
+	for (ref = stale_refs; ref; ref = ref->next) {
+		struct string_list_item *item =
+			string_list_append(abbrev_branch(ref->name), &states->stale);
+		item->util = xstrdup(ref->name);
+	}
+	free_refs(stale_refs);
+	free_refs(fetch_map);
+
+	sort_string_list(&states->new);
+	sort_string_list(&states->tracked);
+	sort_string_list(&states->stale);
+
+	return 0;
+}
+
+struct push_info {
+	char *dest;
+	int forced;
+	enum {
+		PUSH_STATUS_CREATE = 0,
+		PUSH_STATUS_DELETE,
+		PUSH_STATUS_UPTODATE,
+		PUSH_STATUS_FASTFORWARD,
+		PUSH_STATUS_OUTOFDATE,
+		PUSH_STATUS_NOTQUERIED,
+	} status;
+};
+
+static int get_push_ref_states(const struct ref *remote_refs,
+	struct ref_states *states)
+{
+	struct remote *remote = states->remote;
+	struct ref *ref, *local_refs, *push_map;
+	if (remote->mirror)
+		return 0;
+
+	local_refs = get_local_heads();
+	push_map = copy_ref_list(remote_refs);
+
+	match_refs(local_refs, &push_map, remote->push_refspec_nr,
+		   remote->push_refspec, MATCH_REFS_NONE);
+
+	states->push.strdup_strings = 1;
+	for (ref = push_map; ref; ref = ref->next) {
+		struct string_list_item *item;
+		struct push_info *info;
+
+		if (!ref->peer_ref)
+			continue;
+		hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
+
+		item = string_list_append(abbrev_branch(ref->peer_ref->name),
+					  &states->push);
+		item->util = xcalloc(sizeof(struct push_info), 1);
+		info = item->util;
+		info->forced = ref->force;
+		info->dest = xstrdup(abbrev_branch(ref->name));
+
+		if (is_null_sha1(ref->new_sha1)) {
+			info->status = PUSH_STATUS_DELETE;
+		} else if (!hashcmp(ref->old_sha1, ref->new_sha1))
+			info->status = PUSH_STATUS_UPTODATE;
+		else if (is_null_sha1(ref->old_sha1))
+			info->status = PUSH_STATUS_CREATE;
+		else if (has_sha1_file(ref->old_sha1) &&
+			 ref_newer(ref->new_sha1, ref->old_sha1))
+			info->status = PUSH_STATUS_FASTFORWARD;
+		else
+			info->status = PUSH_STATUS_OUTOFDATE;
+	}
+	free_refs(local_refs);
+	free_refs(push_map);
+	return 0;
+}
+
+static int get_push_ref_states_noquery(struct ref_states *states)
+{
+	int i;
+	struct remote *remote = states->remote;
+	struct string_list_item *item;
+	struct push_info *info;
+
+	if (remote->mirror)
+		return 0;
+
+	states->push.strdup_strings = 1;
+	if (!remote->push_refspec_nr) {
+		item = string_list_append("(matching)", &states->push);
+		info = item->util = xcalloc(sizeof(struct push_info), 1);
+		info->status = PUSH_STATUS_NOTQUERIED;
+		info->dest = xstrdup(item->string);
+	}
+	for (i = 0; i < remote->push_refspec_nr; i++) {
+		struct refspec *spec = remote->push + i;
+		if (spec->matching)
+			item = string_list_append("(matching)", &states->push);
+		else if (strlen(spec->src))
+			item = string_list_append(spec->src, &states->push);
+		else
+			item = string_list_append("(delete)", &states->push);
+
+		info = item->util = xcalloc(sizeof(struct push_info), 1);
+		info->forced = spec->force;
+		info->status = PUSH_STATUS_NOTQUERIED;
+		info->dest = xstrdup(spec->dst ? spec->dst : item->string);
+	}
+	return 0;
+}
+
+static int get_head_names(const struct ref *remote_refs, struct ref_states *states)
+{
+	struct ref *ref, *matches;
+	struct ref *fetch_map = NULL, **fetch_map_tail = &fetch_map;
+	struct refspec refspec;
+
+	refspec.force = 0;
+	refspec.pattern = 1;
+	refspec.src = refspec.dst = "refs/heads/*";
+	states->heads.strdup_strings = 1;
+	get_fetch_map(remote_refs, &refspec, &fetch_map_tail, 0);
+	matches = guess_remote_head(find_ref_by_name(remote_refs, "HEAD"),
+				    fetch_map, 1);
+	for (ref = matches; ref; ref = ref->next)
+		string_list_append(abbrev_branch(ref->name), &states->heads);
+
+	free_refs(fetch_map);
+	free_refs(matches);
+
+	return 0;
+}
+
+struct known_remote {
+	struct known_remote *next;
+	struct remote *remote;
+};
+
+struct known_remotes {
+	struct remote *to_delete;
+	struct known_remote *list;
+};
+
+static int add_known_remote(struct remote *remote, void *cb_data)
+{
+	struct known_remotes *all = cb_data;
+	struct known_remote *r;
+
+	if (!strcmp(all->to_delete->name, remote->name))
+		return 0;
+
+	r = xmalloc(sizeof(*r));
+	r->remote = remote;
+	r->next = all->list;
+	all->list = r;
+	return 0;
+}
+
+struct branches_for_remote {
+	struct remote *remote;
+	struct string_list *branches, *skipped;
+	struct known_remotes *keep;
+};
+
+static int add_branch_for_removal(const char *refname,
+	const unsigned char *sha1, int flags, void *cb_data)
+{
+	struct branches_for_remote *branches = cb_data;
+	struct refspec refspec;
+	struct string_list_item *item;
+	struct known_remote *kr;
+
+	memset(&refspec, 0, sizeof(refspec));
+	refspec.dst = (char *)refname;
+	if (remote_find_tracking(branches->remote, &refspec))
+		return 0;
+
+	/* don't delete a branch if another remote also uses it */
+	for (kr = branches->keep->list; kr; kr = kr->next) {
+		memset(&refspec, 0, sizeof(refspec));
+		refspec.dst = (char *)refname;
+		if (!remote_find_tracking(kr->remote, &refspec))
+			return 0;
+	}
+
+	/* don't delete non-remote refs */
+	if (prefixcmp(refname, "refs/remotes")) {
+		/* advise user how to delete local branches */
+		if (!prefixcmp(refname, "refs/heads/"))
+			string_list_append(abbrev_branch(refname),
+					   branches->skipped);
+		/* silently skip over other non-remote refs */
+		return 0;
+	}
+
+	/* make sure that symrefs are deleted */
+	if (flags & REF_ISSYMREF)
+		return unlink(git_path("%s", refname));
+
+	item = string_list_append(refname, branches->branches);
+	item->util = xmalloc(20);
+	hashcpy(item->util, sha1);
+
+	return 0;
+}
+
+struct rename_info {
+	const char *old;
+	const char *new;
+	struct string_list *remote_branches;
+};
+
+static int read_remote_branches(const char *refname,
+	const unsigned char *sha1, int flags, void *cb_data)
+{
+	struct rename_info *rename = cb_data;
+	struct strbuf buf = STRBUF_INIT;
+	struct string_list_item *item;
+	int flag;
+	unsigned char orig_sha1[20];
+	const char *symref;
+
+	strbuf_addf(&buf, "refs/remotes/%s", rename->old);
+	if (!prefixcmp(refname, buf.buf)) {
+		item = string_list_append(xstrdup(refname), rename->remote_branches);
+		symref = resolve_ref(refname, orig_sha1, 1, &flag);
+		if (flag & REF_ISSYMREF)
+			item->util = xstrdup(symref);
+		else
+			item->util = NULL;
+	}
+
+	return 0;
+}
+
+static int migrate_file(struct remote *remote)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int i;
+	char *path = NULL;
+
+	strbuf_addf(&buf, "remote.%s.url", remote->name);
+	for (i = 0; i < remote->url_nr; i++)
+		if (git_config_set_multivar(buf.buf, remote->url[i], "^$", 0))
+			return error("Could not append '%s' to '%s'",
+					remote->url[i], buf.buf);
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "remote.%s.push", remote->name);
+	for (i = 0; i < remote->push_refspec_nr; i++)
+		if (git_config_set_multivar(buf.buf, remote->push_refspec[i], "^$", 0))
+			return error("Could not append '%s' to '%s'",
+					remote->push_refspec[i], buf.buf);
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "remote.%s.fetch", remote->name);
+	for (i = 0; i < remote->fetch_refspec_nr; i++)
+		if (git_config_set_multivar(buf.buf, remote->fetch_refspec[i], "^$", 0))
+			return error("Could not append '%s' to '%s'",
+					remote->fetch_refspec[i], buf.buf);
+	if (remote->origin == REMOTE_REMOTES)
+		path = git_path("remotes/%s", remote->name);
+	else if (remote->origin == REMOTE_BRANCHES)
+		path = git_path("branches/%s", remote->name);
+	if (path)
+		unlink_or_warn(path);
+	return 0;
+}
+
+static int mv(int argc, const char **argv)
+{
+	struct option options[] = {
+		OPT_END()
+	};
+	struct remote *oldremote, *newremote;
+	struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT, buf3 = STRBUF_INIT;
+	struct string_list remote_branches = { NULL, 0, 0, 0 };
+	struct rename_info rename;
+	int i;
+
+	if (argc != 3)
+		usage_with_options(builtin_remote_rename_usage, options);
+
+	rename.old = argv[1];
+	rename.new = argv[2];
+	rename.remote_branches = &remote_branches;
+
+	oldremote = remote_get(rename.old);
+	if (!oldremote)
+		die("No such remote: %s", rename.old);
+
+	if (!strcmp(rename.old, rename.new) && oldremote->origin != REMOTE_CONFIG)
+		return migrate_file(oldremote);
+
+	newremote = remote_get(rename.new);
+	if (newremote && (newremote->url_nr > 1 || newremote->fetch_refspec_nr))
+		die("remote %s already exists.", rename.new);
+
+	strbuf_addf(&buf, "refs/heads/test:refs/remotes/%s/test", rename.new);
+	if (!valid_fetch_refspec(buf.buf))
+		die("'%s' is not a valid remote name", rename.new);
+
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "remote.%s", rename.old);
+	strbuf_addf(&buf2, "remote.%s", rename.new);
+	if (git_config_rename_section(buf.buf, buf2.buf) < 1)
+		return error("Could not rename config section '%s' to '%s'",
+				buf.buf, buf2.buf);
+
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "remote.%s.fetch", rename.new);
+	if (git_config_set_multivar(buf.buf, NULL, NULL, 1))
+		return error("Could not remove config section '%s'", buf.buf);
+	for (i = 0; i < oldremote->fetch_refspec_nr; i++) {
+		char *ptr;
+
+		strbuf_reset(&buf2);
+		strbuf_addstr(&buf2, oldremote->fetch_refspec[i]);
+		ptr = strstr(buf2.buf, rename.old);
+		if (ptr)
+			strbuf_splice(&buf2, ptr-buf2.buf, strlen(rename.old),
+					rename.new, strlen(rename.new));
+		if (git_config_set_multivar(buf.buf, buf2.buf, "^$", 0))
+			return error("Could not append '%s'", buf.buf);
+	}
+
+	read_branches();
+	for (i = 0; i < branch_list.nr; i++) {
+		struct string_list_item *item = branch_list.items + i;
+		struct branch_info *info = item->util;
+		if (info->remote_name && !strcmp(info->remote_name, rename.old)) {
+			strbuf_reset(&buf);
+			strbuf_addf(&buf, "branch.%s.remote", item->string);
+			if (git_config_set(buf.buf, rename.new)) {
+				return error("Could not set '%s'", buf.buf);
+			}
+		}
+	}
+
+	/*
+	 * First remove symrefs, then rename the rest, finally create
+	 * the new symrefs.
+	 */
+	for_each_ref(read_remote_branches, &rename);
+	for (i = 0; i < remote_branches.nr; i++) {
+		struct string_list_item *item = remote_branches.items + i;
+		int flag = 0;
+		unsigned char sha1[20];
+
+		resolve_ref(item->string, sha1, 1, &flag);
+		if (!(flag & REF_ISSYMREF))
+			continue;
+		if (delete_ref(item->string, NULL, REF_NODEREF))
+			die("deleting '%s' failed", item->string);
+	}
+	for (i = 0; i < remote_branches.nr; i++) {
+		struct string_list_item *item = remote_branches.items + i;
+
+		if (item->util)
+			continue;
+		strbuf_reset(&buf);
+		strbuf_addstr(&buf, item->string);
+		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old),
+				rename.new, strlen(rename.new));
+		strbuf_reset(&buf2);
+		strbuf_addf(&buf2, "remote: renamed %s to %s",
+				item->string, buf.buf);
+		if (rename_ref(item->string, buf.buf, buf2.buf))
+			die("renaming '%s' failed", item->string);
+	}
+	for (i = 0; i < remote_branches.nr; i++) {
+		struct string_list_item *item = remote_branches.items + i;
+
+		if (!item->util)
+			continue;
+		strbuf_reset(&buf);
+		strbuf_addstr(&buf, item->string);
+		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old),
+				rename.new, strlen(rename.new));
+		strbuf_reset(&buf2);
+		strbuf_addstr(&buf2, item->util);
+		strbuf_splice(&buf2, strlen("refs/remotes/"), strlen(rename.old),
+				rename.new, strlen(rename.new));
+		strbuf_reset(&buf3);
+		strbuf_addf(&buf3, "remote: renamed %s to %s",
+				item->string, buf.buf);
+		if (create_symref(buf.buf, buf2.buf, buf3.buf))
+			die("creating '%s' failed", buf.buf);
+	}
+	return 0;
+}
+
+static int remove_branches(struct string_list *branches)
+{
+	int i, result = 0;
+	for (i = 0; i < branches->nr; i++) {
+		struct string_list_item *item = branches->items + i;
+		const char *refname = item->string;
+		unsigned char *sha1 = item->util;
+
+		if (delete_ref(refname, sha1, 0))
+			result |= error("Could not remove branch %s", refname);
+	}
+	return result;
+}
+
+static int rm(int argc, const char **argv)
+{
+	struct option options[] = {
+		OPT_END()
+	};
+	struct remote *remote;
+	struct strbuf buf = STRBUF_INIT;
+	struct known_remotes known_remotes = { NULL, NULL };
+	struct string_list branches = { NULL, 0, 0, 1 };
+	struct string_list skipped = { NULL, 0, 0, 1 };
+	struct branches_for_remote cb_data = {
+		NULL, &branches, &skipped, &known_remotes
+	};
+	int i, result;
+
+	if (argc != 2)
+		usage_with_options(builtin_remote_rm_usage, options);
+
+	remote = remote_get(argv[1]);
+	if (!remote)
+		die("No such remote: %s", argv[1]);
+
+	known_remotes.to_delete = remote;
+	for_each_remote(add_known_remote, &known_remotes);
+
+	strbuf_addf(&buf, "remote.%s", remote->name);
+	if (git_config_rename_section(buf.buf, NULL) < 1)
+		return error("Could not remove config section '%s'", buf.buf);
+
+	read_branches();
+	for (i = 0; i < branch_list.nr; i++) {
+		struct string_list_item *item = branch_list.items + i;
+		struct branch_info *info = item->util;
+		if (info->remote_name && !strcmp(info->remote_name, remote->name)) {
+			const char *keys[] = { "remote", "merge", NULL }, **k;
+			for (k = keys; *k; k++) {
+				strbuf_reset(&buf);
+				strbuf_addf(&buf, "branch.%s.%s",
+						item->string, *k);
+				if (git_config_set(buf.buf, NULL)) {
+					strbuf_release(&buf);
+					return -1;
+				}
+			}
+		}
+	}
+
+	/*
+	 * We cannot just pass a function to for_each_ref() which deletes
+	 * the branches one by one, since for_each_ref() relies on cached
+	 * refs, which are invalidated when deleting a branch.
+	 */
+	cb_data.remote = remote;
+	result = for_each_ref(add_branch_for_removal, &cb_data);
+	strbuf_release(&buf);
+
+	if (!result)
+		result = remove_branches(&branches);
+	string_list_clear(&branches, 1);
+
+	if (skipped.nr) {
+		fprintf(stderr, skipped.nr == 1 ?
+			"Note: A non-remote branch was not removed; "
+			"to delete it, use:\n" :
+			"Note: Non-remote branches were not removed; "
+			"to delete them, use:\n");
+		for (i = 0; i < skipped.nr; i++)
+			fprintf(stderr, "  git branch -d %s\n",
+				skipped.items[i].string);
+	}
+	string_list_clear(&skipped, 0);
+
+	return result;
+}
+
+static void clear_push_info(void *util, const char *string)
+{
+	struct push_info *info = util;
+	free(info->dest);
+	free(info);
+}
+
+static void free_remote_ref_states(struct ref_states *states)
+{
+	string_list_clear(&states->new, 0);
+	string_list_clear(&states->stale, 1);
+	string_list_clear(&states->tracked, 0);
+	string_list_clear(&states->heads, 0);
+	string_list_clear_func(&states->push, clear_push_info);
+}
+
+static int append_ref_to_tracked_list(const char *refname,
+	const unsigned char *sha1, int flags, void *cb_data)
+{
+	struct ref_states *states = cb_data;
+	struct refspec refspec;
+
+	if (flags & REF_ISSYMREF)
+		return 0;
+
+	memset(&refspec, 0, sizeof(refspec));
+	refspec.dst = (char *)refname;
+	if (!remote_find_tracking(states->remote, &refspec))
+		string_list_append(abbrev_branch(refspec.src), &states->tracked);
+
+	return 0;
+}
+
+static int get_remote_ref_states(const char *name,
+				 struct ref_states *states,
+				 int query)
+{
+	struct transport *transport;
+	const struct ref *remote_refs;
+
+	states->remote = remote_get(name);
+	if (!states->remote)
+		return error("No such remote: %s", name);
+
+	read_branches();
+
+	if (query) {
+		transport = transport_get(states->remote, states->remote->url_nr > 0 ?
+			states->remote->url[0] : NULL);
+		remote_refs = transport_get_remote_refs(transport);
+		transport_disconnect(transport);
+
+		states->queried = 1;
+		if (query & GET_REF_STATES)
+			get_ref_states(remote_refs, states);
+		if (query & GET_HEAD_NAMES)
+			get_head_names(remote_refs, states);
+		if (query & GET_PUSH_REF_STATES)
+			get_push_ref_states(remote_refs, states);
+	} else {
+		for_each_ref(append_ref_to_tracked_list, states);
+		sort_string_list(&states->tracked);
+		get_push_ref_states_noquery(states);
+	}
+
+	return 0;
+}
+
+struct show_info {
+	struct string_list *list;
+	struct ref_states *states;
+	int width, width2;
+	int any_rebase;
+};
+
+static int add_remote_to_show_info(struct string_list_item *item, void *cb_data)
+{
+	struct show_info *info = cb_data;
+	int n = strlen(item->string);
+	if (n > info->width)
+		info->width = n;
+	string_list_insert(item->string, info->list);
+	return 0;
+}
+
+static int show_remote_info_item(struct string_list_item *item, void *cb_data)
+{
+	struct show_info *info = cb_data;
+	struct ref_states *states = info->states;
+	const char *name = item->string;
+
+	if (states->queried) {
+		const char *fmt = "%s";
+		const char *arg = "";
+		if (string_list_has_string(&states->new, name)) {
+			fmt = " new (next fetch will store in remotes/%s)";
+			arg = states->remote->name;
+		} else if (string_list_has_string(&states->tracked, name))
+			arg = " tracked";
+		else if (string_list_has_string(&states->stale, name))
+			arg = " stale (use 'git remote prune' to remove)";
+		else
+			arg = " ???";
+		printf("    %-*s", info->width, name);
+		printf(fmt, arg);
+		printf("\n");
+	} else
+		printf("    %s\n", name);
+
+	return 0;
+}
+
+static int add_local_to_show_info(struct string_list_item *branch_item, void *cb_data)
+{
+	struct show_info *show_info = cb_data;
+	struct ref_states *states = show_info->states;
+	struct branch_info *branch_info = branch_item->util;
+	struct string_list_item *item;
+	int n;
+
+	if (!branch_info->merge.nr || !branch_info->remote_name ||
+	    strcmp(states->remote->name, branch_info->remote_name))
+		return 0;
+	if ((n = strlen(branch_item->string)) > show_info->width)
+		show_info->width = n;
+	if (branch_info->rebase)
+		show_info->any_rebase = 1;
+
+	item = string_list_insert(branch_item->string, show_info->list);
+	item->util = branch_info;
+
+	return 0;
+}
+
+static int show_local_info_item(struct string_list_item *item, void *cb_data)
+{
+	struct show_info *show_info = cb_data;
+	struct branch_info *branch_info = item->util;
+	struct string_list *merge = &branch_info->merge;
+	const char *also;
+	int i;
+
+	if (branch_info->rebase && branch_info->merge.nr > 1) {
+		error("invalid branch.%s.merge; cannot rebase onto > 1 branch",
+			item->string);
+		return 0;
+	}
+
+	printf("    %-*s ", show_info->width, item->string);
+	if (branch_info->rebase) {
+		printf("rebases onto remote %s\n", merge->items[0].string);
+		return 0;
+	} else if (show_info->any_rebase) {
+		printf(" merges with remote %s\n", merge->items[0].string);
+		also = "    and with remote";
+	} else {
+		printf("merges with remote %s\n", merge->items[0].string);
+		also = "   and with remote";
+	}
+	for (i = 1; i < merge->nr; i++)
+		printf("    %-*s %s %s\n", show_info->width, "", also,
+		       merge->items[i].string);
+
+	return 0;
+}
+
+static int add_push_to_show_info(struct string_list_item *push_item, void *cb_data)
+{
+	struct show_info *show_info = cb_data;
+	struct push_info *push_info = push_item->util;
+	struct string_list_item *item;
+	int n;
+	if ((n = strlen(push_item->string)) > show_info->width)
+		show_info->width = n;
+	if ((n = strlen(push_info->dest)) > show_info->width2)
+		show_info->width2 = n;
+	item = string_list_append(push_item->string, show_info->list);
+	item->util = push_item->util;
+	return 0;
+}
+
+/*
+ * Sorting comparison for a string list that has push_info
+ * structs in its util field
+ */
+static int cmp_string_with_push(const void *va, const void *vb)
+{
+	const struct string_list_item *a = va;
+	const struct string_list_item *b = vb;
+	const struct push_info *a_push = a->util;
+	const struct push_info *b_push = b->util;
+	int cmp = strcmp(a->string, b->string);
+	return cmp ? cmp : strcmp(a_push->dest, b_push->dest);
+}
+
+static int show_push_info_item(struct string_list_item *item, void *cb_data)
+{
+	struct show_info *show_info = cb_data;
+	struct push_info *push_info = item->util;
+	char *src = item->string, *status = NULL;
+
+	switch (push_info->status) {
+	case PUSH_STATUS_CREATE:
+		status = "create";
+		break;
+	case PUSH_STATUS_DELETE:
+		status = "delete";
+		src = "(none)";
+		break;
+	case PUSH_STATUS_UPTODATE:
+		status = "up to date";
+		break;
+	case PUSH_STATUS_FASTFORWARD:
+		status = "fast-forwardable";
+		break;
+	case PUSH_STATUS_OUTOFDATE:
+		status = "local out of date";
+		break;
+	case PUSH_STATUS_NOTQUERIED:
+		break;
+	}
+	if (status)
+		printf("    %-*s %s to %-*s (%s)\n", show_info->width, src,
+			push_info->forced ? "forces" : "pushes",
+			show_info->width2, push_info->dest, status);
+	else
+		printf("    %-*s %s to %s\n", show_info->width, src,
+			push_info->forced ? "forces" : "pushes",
+			push_info->dest);
+	return 0;
+}
+
+static int show(int argc, const char **argv)
+{
+	int no_query = 0, result = 0, query_flag = 0;
+	struct option options[] = {
+		OPT_BOOLEAN('n', NULL, &no_query, "do not query remotes"),
+		OPT_END()
+	};
+	struct ref_states states;
+	struct string_list info_list = { NULL, 0, 0, 0 };
+	struct show_info info;
+
+	argc = parse_options(argc, argv, NULL, options, builtin_remote_show_usage,
+			     0);
+
+	if (argc < 1)
+		return show_all();
+
+	if (!no_query)
+		query_flag = (GET_REF_STATES | GET_HEAD_NAMES | GET_PUSH_REF_STATES);
+
+	memset(&states, 0, sizeof(states));
+	memset(&info, 0, sizeof(info));
+	info.states = &states;
+	info.list = &info_list;
+	for (; argc; argc--, argv++) {
+		int i;
+		const char **url;
+		int url_nr;
+
+		get_remote_ref_states(*argv, &states, query_flag);
+
+		printf("* remote %s\n", *argv);
+		printf("  Fetch URL: %s\n", states.remote->url_nr > 0 ?
+			states.remote->url[0] : "(no URL)");
+		if (states.remote->pushurl_nr) {
+			url = states.remote->pushurl;
+			url_nr = states.remote->pushurl_nr;
+		} else {
+			url = states.remote->url;
+			url_nr = states.remote->url_nr;
+		}
+		for (i=0; i < url_nr; i++)
+			printf("  Push  URL: %s\n", url[i]);
+		if (!i)
+			printf("  Push  URL: %s\n", "(no URL)");
+		if (no_query)
+			printf("  HEAD branch: (not queried)\n");
+		else if (!states.heads.nr)
+			printf("  HEAD branch: (unknown)\n");
+		else if (states.heads.nr == 1)
+			printf("  HEAD branch: %s\n", states.heads.items[0].string);
+		else {
+			printf("  HEAD branch (remote HEAD is ambiguous,"
+			       " may be one of the following):\n");
+			for (i = 0; i < states.heads.nr; i++)
+				printf("    %s\n", states.heads.items[i].string);
+		}
+
+		/* remote branch info */
+		info.width = 0;
+		for_each_string_list(add_remote_to_show_info, &states.new, &info);
+		for_each_string_list(add_remote_to_show_info, &states.tracked, &info);
+		for_each_string_list(add_remote_to_show_info, &states.stale, &info);
+		if (info.list->nr)
+			printf("  Remote branch%s:%s\n",
+			       info.list->nr > 1 ? "es" : "",
+				no_query ? " (status not queried)" : "");
+		for_each_string_list(show_remote_info_item, info.list, &info);
+		string_list_clear(info.list, 0);
+
+		/* git pull info */
+		info.width = 0;
+		info.any_rebase = 0;
+		for_each_string_list(add_local_to_show_info, &branch_list, &info);
+		if (info.list->nr)
+			printf("  Local branch%s configured for 'git pull':\n",
+			       info.list->nr > 1 ? "es" : "");
+		for_each_string_list(show_local_info_item, info.list, &info);
+		string_list_clear(info.list, 0);
+
+		/* git push info */
+		if (states.remote->mirror)
+			printf("  Local refs will be mirrored by 'git push'\n");
+
+		info.width = info.width2 = 0;
+		for_each_string_list(add_push_to_show_info, &states.push, &info);
+		qsort(info.list->items, info.list->nr,
+			sizeof(*info.list->items), cmp_string_with_push);
+		if (info.list->nr)
+			printf("  Local ref%s configured for 'git push'%s:\n",
+				info.list->nr > 1 ? "s" : "",
+				no_query ? " (status not queried)" : "");
+		for_each_string_list(show_push_info_item, info.list, &info);
+		string_list_clear(info.list, 0);
+
+		free_remote_ref_states(&states);
+	}
+
+	return result;
+}
+
+static int set_head(int argc, const char **argv)
+{
+	int i, opt_a = 0, opt_d = 0, result = 0;
+	struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT;
+	char *head_name = NULL;
+
+	struct option options[] = {
+		OPT_BOOLEAN('a', "auto", &opt_a,
+			    "set refs/remotes/<name>/HEAD according to remote"),
+		OPT_BOOLEAN('d', "delete", &opt_d,
+			    "delete refs/remotes/<name>/HEAD"),
+		OPT_END()
+	};
+	argc = parse_options(argc, argv, NULL, options, builtin_remote_sethead_usage,
+			     0);
+	if (argc)
+		strbuf_addf(&buf, "refs/remotes/%s/HEAD", argv[0]);
+
+	if (!opt_a && !opt_d && argc == 2) {
+		head_name = xstrdup(argv[1]);
+	} else if (opt_a && !opt_d && argc == 1) {
+		struct ref_states states;
+		memset(&states, 0, sizeof(states));
+		get_remote_ref_states(argv[0], &states, GET_HEAD_NAMES);
+		if (!states.heads.nr)
+			result |= error("Cannot determine remote HEAD");
+		else if (states.heads.nr > 1) {
+			result |= error("Multiple remote HEAD branches. "
+					"Please choose one explicitly with:");
+			for (i = 0; i < states.heads.nr; i++)
+				fprintf(stderr, "  git remote set-head %s %s\n",
+					argv[0], states.heads.items[i].string);
+		} else
+			head_name = xstrdup(states.heads.items[0].string);
+		free_remote_ref_states(&states);
+	} else if (opt_d && !opt_a && argc == 1) {
+		if (delete_ref(buf.buf, NULL, REF_NODEREF))
+			result |= error("Could not delete %s", buf.buf);
+	} else
+		usage_with_options(builtin_remote_sethead_usage, options);
+
+	if (head_name) {
+		unsigned char sha1[20];
+		strbuf_addf(&buf2, "refs/remotes/%s/%s", argv[0], head_name);
+		/* make sure it's valid */
+		if (!resolve_ref(buf2.buf, sha1, 1, NULL))
+			result |= error("Not a valid ref: %s", buf2.buf);
+		else if (create_symref(buf.buf, buf2.buf, "remote set-head"))
+			result |= error("Could not setup %s", buf.buf);
+		if (opt_a)
+			printf("%s/HEAD set to %s\n", argv[0], head_name);
+		free(head_name);
+	}
+
+	strbuf_release(&buf);
+	strbuf_release(&buf2);
+	return result;
+}
+
+static int prune(int argc, const char **argv)
+{
+	int dry_run = 0, result = 0;
+	struct option options[] = {
+		OPT__DRY_RUN(&dry_run),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, NULL, options, builtin_remote_prune_usage,
+			     0);
+
+	if (argc < 1)
+		usage_with_options(builtin_remote_prune_usage, options);
+
+	for (; argc; argc--, argv++)
+		result |= prune_remote(*argv, dry_run);
+
+	return result;
+}
+
+static int prune_remote(const char *remote, int dry_run)
+{
+	int result = 0, i;
+	struct ref_states states;
+	const char *dangling_msg = dry_run
+		? " %s will become dangling!\n"
+		: " %s has become dangling!\n";
+
+	memset(&states, 0, sizeof(states));
+	get_remote_ref_states(remote, &states, GET_REF_STATES);
+
+	if (states.stale.nr) {
+		printf("Pruning %s\n", remote);
+		printf("URL: %s\n",
+		       states.remote->url_nr
+		       ? states.remote->url[0]
+		       : "(no URL)");
+	}
+
+	for (i = 0; i < states.stale.nr; i++) {
+		const char *refname = states.stale.items[i].util;
+
+		if (!dry_run)
+			result |= delete_ref(refname, NULL, 0);
+
+		printf(" * [%s] %s\n", dry_run ? "would prune" : "pruned",
+		       abbrev_ref(refname, "refs/remotes/"));
+		warn_dangling_symref(stdout, dangling_msg, refname);
+	}
+
+	free_remote_ref_states(&states);
+	return result;
+}
+
+static int get_remote_default(const char *key, const char *value, void *priv)
+{
+	if (strcmp(key, "remotes.default") == 0) {
+		int *found = priv;
+		*found = 1;
+	}
+	return 0;
+}
+
+static int update(int argc, const char **argv)
+{
+	int i, prune = 0;
+	struct option options[] = {
+		OPT_BOOLEAN('p', "prune", &prune,
+			    "prune remotes after fetching"),
+		OPT_END()
+	};
+	const char **fetch_argv;
+	int fetch_argc = 0;
+	int default_defined = 0;
+
+	fetch_argv = xmalloc(sizeof(char *) * (argc+5));
+
+	argc = parse_options(argc, argv, NULL, options, builtin_remote_update_usage,
+			     PARSE_OPT_KEEP_ARGV0);
+
+	fetch_argv[fetch_argc++] = "fetch";
+
+	if (prune)
+		fetch_argv[fetch_argc++] = "--prune";
+	if (verbose)
+		fetch_argv[fetch_argc++] = "-v";
+	fetch_argv[fetch_argc++] = "--multiple";
+	if (argc < 2)
+		fetch_argv[fetch_argc++] = "default";
+	for (i = 1; i < argc; i++)
+		fetch_argv[fetch_argc++] = argv[i];
+
+	if (strcmp(fetch_argv[fetch_argc-1], "default") == 0) {
+		git_config(get_remote_default, &default_defined);
+		if (!default_defined)
+			fetch_argv[fetch_argc-1] = "--all";
+	}
+
+	fetch_argv[fetch_argc] = NULL;
+
+	return run_command_v_opt(fetch_argv, RUN_GIT_CMD);
+}
+
+static int set_url(int argc, const char **argv)
+{
+	int i, push_mode = 0, add_mode = 0, delete_mode = 0;
+	int matches = 0, negative_matches = 0;
+	const char *remotename = NULL;
+	const char *newurl = NULL;
+	const char *oldurl = NULL;
+	struct remote *remote;
+	regex_t old_regex;
+	const char **urlset;
+	int urlset_nr;
+	struct strbuf name_buf = STRBUF_INIT;
+	struct option options[] = {
+		OPT_BOOLEAN('\0', "push", &push_mode,
+			    "manipulate push URLs"),
+		OPT_BOOLEAN('\0', "add", &add_mode,
+			    "add URL"),
+		OPT_BOOLEAN('\0', "delete", &delete_mode,
+			    "delete URLs"),
+		OPT_END()
+	};
+	argc = parse_options(argc, argv, NULL, options, builtin_remote_update_usage,
+			     PARSE_OPT_KEEP_ARGV0);
+
+	if (add_mode && delete_mode)
+		die("--add --delete doesn't make sense");
+
+	if (argc < 3 || argc > 4 || ((add_mode || delete_mode) && argc != 3))
+		usage_with_options(builtin_remote_seturl_usage, options);
+
+	remotename = argv[1];
+	newurl = argv[2];
+	if (argc > 3)
+		oldurl = argv[3];
+
+	if (delete_mode)
+		oldurl = newurl;
+
+	if (!remote_is_configured(remotename))
+		die("No such remote '%s'", remotename);
+	remote = remote_get(remotename);
+
+	if (push_mode) {
+		strbuf_addf(&name_buf, "remote.%s.pushurl", remotename);
+		urlset = remote->pushurl;
+		urlset_nr = remote->pushurl_nr;
+	} else {
+		strbuf_addf(&name_buf, "remote.%s.url", remotename);
+		urlset = remote->url;
+		urlset_nr = remote->url_nr;
+	}
+
+	/* Special cases that add new entry. */
+	if ((!oldurl && !delete_mode) || add_mode) {
+		if (add_mode)
+			git_config_set_multivar(name_buf.buf, newurl,
+				"^$", 0);
+		else
+			git_config_set(name_buf.buf, newurl);
+		strbuf_release(&name_buf);
+		return 0;
+	}
+
+	/* Old URL specified. Demand that one matches. */
+	if (regcomp(&old_regex, oldurl, REG_EXTENDED))
+		die("Invalid old URL pattern: %s", oldurl);
+
+	for (i = 0; i < urlset_nr; i++)
+		if (!regexec(&old_regex, urlset[i], 0, NULL, 0))
+			matches++;
+		else
+			negative_matches++;
+	if (!delete_mode && !matches)
+		die("No such URL found: %s", oldurl);
+	if (delete_mode && !negative_matches && !push_mode)
+		die("Will not delete all non-push URLs");
+
+	regfree(&old_regex);
+
+	if (!delete_mode)
+		git_config_set_multivar(name_buf.buf, newurl, oldurl, 0);
+	else
+		git_config_set_multivar(name_buf.buf, NULL, oldurl, 1);
+	return 0;
+}
+
+static int get_one_entry(struct remote *remote, void *priv)
+{
+	struct string_list *list = priv;
+	struct strbuf url_buf = STRBUF_INIT;
+	const char **url;
+	int i, url_nr;
+
+	if (remote->url_nr > 0) {
+		strbuf_addf(&url_buf, "%s (fetch)", remote->url[0]);
+		string_list_append(remote->name, list)->util =
+				strbuf_detach(&url_buf, NULL);
+	} else
+		string_list_append(remote->name, list)->util = NULL;
+	if (remote->pushurl_nr) {
+		url = remote->pushurl;
+		url_nr = remote->pushurl_nr;
+	} else {
+		url = remote->url;
+		url_nr = remote->url_nr;
+	}
+	for (i = 0; i < url_nr; i++)
+	{
+		strbuf_addf(&url_buf, "%s (push)", url[i]);
+		string_list_append(remote->name, list)->util =
+				strbuf_detach(&url_buf, NULL);
+	}
+
+	return 0;
+}
+
+static int show_all(void)
+{
+	struct string_list list = { NULL, 0, 0 };
+	int result;
+
+	list.strdup_strings = 1;
+	result = for_each_remote(get_one_entry, &list);
+
+	if (!result) {
+		int i;
+
+		sort_string_list(&list);
+		for (i = 0; i < list.nr; i++) {
+			struct string_list_item *item = list.items + i;
+			if (verbose)
+				printf("%s\t%s\n", item->string,
+					item->util ? (const char *)item->util : "");
+			else {
+				if (i && !strcmp((item - 1)->string, item->string))
+					continue;
+				printf("%s\n", item->string);
+			}
+		}
+	}
+	string_list_clear(&list, 1);
+	return result;
+}
+
+int cmd_remote(int argc, const char **argv, const char *prefix)
+{
+	struct option options[] = {
+		OPT_BOOLEAN('v', "verbose", &verbose, "be verbose; must be placed before a subcommand"),
+		OPT_END()
+	};
+	int result;
+
+	argc = parse_options(argc, argv, prefix, options, builtin_remote_usage,
+		PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (argc < 1)
+		result = show_all();
+	else if (!strcmp(argv[0], "add"))
+		result = add(argc, argv);
+	else if (!strcmp(argv[0], "rename"))
+		result = mv(argc, argv);
+	else if (!strcmp(argv[0], "rm"))
+		result = rm(argc, argv);
+	else if (!strcmp(argv[0], "set-head"))
+		result = set_head(argc, argv);
+	else if (!strcmp(argv[0], "set-url"))
+		result = set_url(argc, argv);
+	else if (!strcmp(argv[0], "show"))
+		result = show(argc, argv);
+	else if (!strcmp(argv[0], "prune"))
+		result = prune(argc, argv);
+	else if (!strcmp(argv[0], "update"))
+		result = update(argc, argv);
+	else {
+		error("Unknown subcommand: %s", argv[0]);
+		usage_with_options(builtin_remote_usage, options);
+	}
+
+	return result ? 1 : 0;
+}
diff --git a/builtin/replace.c b/builtin/replace.c
new file mode 100644
index 0000000..fe3a647
--- /dev/null
+++ b/builtin/replace.c
@@ -0,0 +1,159 @@
+/*
+ * Builtin "git replace"
+ *
+ * Copyright (c) 2008 Christian Couder <chriscool@tuxfamily.org>
+ *
+ * Based on builtin-tag.c by Kristian Høgsberg <krh@redhat.com>
+ * and Carlos Rica <jasampler@gmail.com> that was itself based on
+ * git-tag.sh and mktag.c by Linus Torvalds.
+ */
+
+#include "cache.h"
+#include "builtin.h"
+#include "refs.h"
+#include "parse-options.h"
+
+static const char * const git_replace_usage[] = {
+	"git replace [-f] <object> <replacement>",
+	"git replace -d <object>...",
+	"git replace -l [<pattern>]",
+	NULL
+};
+
+static int show_reference(const char *refname, const unsigned char *sha1,
+			  int flag, void *cb_data)
+{
+	const char *pattern = cb_data;
+
+	if (!fnmatch(pattern, refname, 0))
+		printf("%s\n", refname);
+
+	return 0;
+}
+
+static int list_replace_refs(const char *pattern)
+{
+	if (pattern == NULL)
+		pattern = "*";
+
+	for_each_replace_ref(show_reference, (void *) pattern);
+
+	return 0;
+}
+
+typedef int (*each_replace_name_fn)(const char *name, const char *ref,
+				    const unsigned char *sha1);
+
+static int for_each_replace_name(const char **argv, each_replace_name_fn fn)
+{
+	const char **p;
+	char ref[PATH_MAX];
+	int had_error = 0;
+	unsigned char sha1[20];
+
+	for (p = argv; *p; p++) {
+		if (snprintf(ref, sizeof(ref), "refs/replace/%s", *p)
+					>= sizeof(ref)) {
+			error("replace ref name too long: %.*s...", 50, *p);
+			had_error = 1;
+			continue;
+		}
+		if (!resolve_ref(ref, sha1, 1, NULL)) {
+			error("replace ref '%s' not found.", *p);
+			had_error = 1;
+			continue;
+		}
+		if (fn(*p, ref, sha1))
+			had_error = 1;
+	}
+	return had_error;
+}
+
+static int delete_replace_ref(const char *name, const char *ref,
+			      const unsigned char *sha1)
+{
+	if (delete_ref(ref, sha1, 0))
+		return 1;
+	printf("Deleted replace ref '%s'\n", name);
+	return 0;
+}
+
+static int replace_object(const char *object_ref, const char *replace_ref,
+			  int force)
+{
+	unsigned char object[20], prev[20], repl[20];
+	char ref[PATH_MAX];
+	struct ref_lock *lock;
+
+	if (get_sha1(object_ref, object))
+		die("Failed to resolve '%s' as a valid ref.", object_ref);
+	if (get_sha1(replace_ref, repl))
+		die("Failed to resolve '%s' as a valid ref.", replace_ref);
+
+	if (snprintf(ref, sizeof(ref),
+		     "refs/replace/%s",
+		     sha1_to_hex(object)) > sizeof(ref) - 1)
+		die("replace ref name too long: %.*s...", 50, ref);
+	if (check_ref_format(ref))
+		die("'%s' is not a valid ref name.", ref);
+
+	if (!resolve_ref(ref, prev, 1, NULL))
+		hashclr(prev);
+	else if (!force)
+		die("replace ref '%s' already exists", ref);
+
+	lock = lock_any_ref_for_update(ref, prev, 0);
+	if (!lock)
+		die("%s: cannot lock the ref", ref);
+	if (write_ref_sha1(lock, repl, NULL) < 0)
+		die("%s: cannot update the ref", ref);
+
+	return 0;
+}
+
+int cmd_replace(int argc, const char **argv, const char *prefix)
+{
+	int list = 0, delete = 0, force = 0;
+	struct option options[] = {
+		OPT_BOOLEAN('l', NULL, &list, "list replace refs"),
+		OPT_BOOLEAN('d', NULL, &delete, "delete replace refs"),
+		OPT_BOOLEAN('f', NULL, &force, "replace the ref if it exists"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);
+
+	if (list && delete)
+		usage_msg_opt("-l and -d cannot be used together",
+			      git_replace_usage, options);
+
+	if (force && (list || delete))
+		usage_msg_opt("-f cannot be used with -d or -l",
+			      git_replace_usage, options);
+
+	/* Delete refs */
+	if (delete) {
+		if (argc < 1)
+			usage_msg_opt("-d needs at least one argument",
+				      git_replace_usage, options);
+		return for_each_replace_name(argv, delete_replace_ref);
+	}
+
+	/* Replace object */
+	if (!list && argc) {
+		if (argc != 2)
+			usage_msg_opt("bad number of arguments",
+				      git_replace_usage, options);
+		return replace_object(argv[0], argv[1], force);
+	}
+
+	/* List refs, even if "list" is not set */
+	if (argc > 1)
+		usage_msg_opt("only one pattern can be given with -l",
+			      git_replace_usage, options);
+	if (force)
+		usage_msg_opt("-f needs some arguments",
+			      git_replace_usage, options);
+
+	return list_replace_refs(argv[0]);
+}
diff --git a/builtin/rerere.c b/builtin/rerere.c
new file mode 100644
index 0000000..34f9ace
--- /dev/null
+++ b/builtin/rerere.c
@@ -0,0 +1,155 @@
+#include "builtin.h"
+#include "cache.h"
+#include "dir.h"
+#include "string-list.h"
+#include "rerere.h"
+#include "xdiff/xdiff.h"
+#include "xdiff-interface.h"
+
+static const char git_rerere_usage[] =
+"git rerere [clear | status | diff | gc]";
+
+/* these values are days */
+static int cutoff_noresolve = 15;
+static int cutoff_resolve = 60;
+
+static time_t rerere_created_at(const char *name)
+{
+	struct stat st;
+	return stat(rerere_path(name, "preimage"), &st) ? (time_t) 0 : st.st_mtime;
+}
+
+static void unlink_rr_item(const char *name)
+{
+	unlink(rerere_path(name, "thisimage"));
+	unlink(rerere_path(name, "preimage"));
+	unlink(rerere_path(name, "postimage"));
+	rmdir(git_path("rr-cache/%s", name));
+}
+
+static int git_rerere_gc_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "gc.rerereresolved"))
+		cutoff_resolve = git_config_int(var, value);
+	else if (!strcmp(var, "gc.rerereunresolved"))
+		cutoff_noresolve = git_config_int(var, value);
+	else
+		return git_default_config(var, value, cb);
+	return 0;
+}
+
+static void garbage_collect(struct string_list *rr)
+{
+	struct string_list to_remove = { NULL, 0, 0, 1 };
+	DIR *dir;
+	struct dirent *e;
+	int i, cutoff;
+	time_t now = time(NULL), then;
+
+	git_config(git_rerere_gc_config, NULL);
+	dir = opendir(git_path("rr-cache"));
+	if (!dir)
+		die_errno("unable to open rr-cache directory");
+	while ((e = readdir(dir))) {
+		if (is_dot_or_dotdot(e->d_name))
+			continue;
+		then = rerere_created_at(e->d_name);
+		if (!then)
+			continue;
+		cutoff = (has_rerere_resolution(e->d_name)
+			  ? cutoff_resolve : cutoff_noresolve);
+		if (then < now - cutoff * 86400)
+			string_list_append(e->d_name, &to_remove);
+	}
+	for (i = 0; i < to_remove.nr; i++)
+		unlink_rr_item(to_remove.items[i].string);
+	string_list_clear(&to_remove, 0);
+}
+
+static int outf(void *dummy, mmbuffer_t *ptr, int nbuf)
+{
+	int i;
+	for (i = 0; i < nbuf; i++)
+		if (write_in_full(1, ptr[i].ptr, ptr[i].size) != ptr[i].size)
+			return -1;
+	return 0;
+}
+
+static int diff_two(const char *file1, const char *label1,
+		const char *file2, const char *label2)
+{
+	xpparam_t xpp;
+	xdemitconf_t xecfg;
+	xdemitcb_t ecb;
+	mmfile_t minus, plus;
+
+	if (read_mmfile(&minus, file1) || read_mmfile(&plus, file2))
+		return 1;
+
+	printf("--- a/%s\n+++ b/%s\n", label1, label2);
+	fflush(stdout);
+	memset(&xpp, 0, sizeof(xpp));
+	xpp.flags = XDF_NEED_MINIMAL;
+	memset(&xecfg, 0, sizeof(xecfg));
+	xecfg.ctxlen = 3;
+	ecb.outf = outf;
+	xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
+
+	free(minus.ptr);
+	free(plus.ptr);
+	return 0;
+}
+
+int cmd_rerere(int argc, const char **argv, const char *prefix)
+{
+	struct string_list merge_rr = { NULL, 0, 0, 1 };
+	int i, fd, flags = 0;
+
+	if (2 < argc) {
+		if (!strcmp(argv[1], "-h"))
+			usage(git_rerere_usage);
+		if (!strcmp(argv[1], "--rerere-autoupdate"))
+			flags = RERERE_AUTOUPDATE;
+		else if (!strcmp(argv[1], "--no-rerere-autoupdate"))
+			flags = RERERE_NOAUTOUPDATE;
+		if (flags) {
+			argc--;
+			argv++;
+		}
+	}
+	if (argc < 2)
+		return rerere(flags);
+
+	if (!strcmp(argv[1], "forget")) {
+		const char **pathspec = get_pathspec(prefix, argv + 2);
+		return rerere_forget(pathspec);
+	}
+
+	fd = setup_rerere(&merge_rr, flags);
+	if (fd < 0)
+		return 0;
+
+	if (!strcmp(argv[1], "clear")) {
+		for (i = 0; i < merge_rr.nr; i++) {
+			const char *name = (const char *)merge_rr.items[i].util;
+			if (!has_rerere_resolution(name))
+				unlink_rr_item(name);
+		}
+		unlink_or_warn(git_path("rr-cache/MERGE_RR"));
+	} else if (!strcmp(argv[1], "gc"))
+		garbage_collect(&merge_rr);
+	else if (!strcmp(argv[1], "status"))
+		for (i = 0; i < merge_rr.nr; i++)
+			printf("%s\n", merge_rr.items[i].string);
+	else if (!strcmp(argv[1], "diff"))
+		for (i = 0; i < merge_rr.nr; i++) {
+			const char *path = merge_rr.items[i].string;
+			const char *name = (const char *)merge_rr.items[i].util;
+			diff_two(rerere_path(name, "preimage"), path, path, path);
+		}
+	else
+		usage(git_rerere_usage);
+
+	string_list_clear(&merge_rr, 1);
+	return 0;
+}
diff --git a/builtin/reset.c b/builtin/reset.c
new file mode 100644
index 0000000..0f5022e
--- /dev/null
+++ b/builtin/reset.c
@@ -0,0 +1,356 @@
+/*
+ * "git reset" builtin command
+ *
+ * Copyright (c) 2007 Carlos Rica
+ *
+ * Based on git-reset.sh, which is
+ *
+ * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
+ */
+#include "cache.h"
+#include "tag.h"
+#include "object.h"
+#include "commit.h"
+#include "run-command.h"
+#include "refs.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "tree.h"
+#include "branch.h"
+#include "parse-options.h"
+#include "unpack-trees.h"
+#include "cache-tree.h"
+
+static const char * const git_reset_usage[] = {
+	"git reset [--mixed | --soft | --hard | --merge] [-q] [<commit>]",
+	"git reset [--mixed] <commit> [--] <paths>...",
+	NULL
+};
+
+enum reset_type { MIXED, SOFT, HARD, MERGE, NONE };
+static const char *reset_type_names[] = { "mixed", "soft", "hard", "merge", NULL };
+
+static char *args_to_str(const char **argv)
+{
+	char *buf = NULL;
+	unsigned long len, space = 0, nr = 0;
+
+	for (; *argv; argv++) {
+		len = strlen(*argv);
+		ALLOC_GROW(buf, nr + 1 + len, space);
+		if (nr)
+			buf[nr++] = ' ';
+		memcpy(buf + nr, *argv, len);
+		nr += len;
+	}
+	ALLOC_GROW(buf, nr + 1, space);
+	buf[nr] = '\0';
+
+	return buf;
+}
+
+static inline int is_merge(void)
+{
+	return !access(git_path("MERGE_HEAD"), F_OK);
+}
+
+static int reset_index_file(const unsigned char *sha1, int reset_type, int quiet)
+{
+	int nr = 1;
+	int newfd;
+	struct tree_desc desc[2];
+	struct unpack_trees_options opts;
+	struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+
+	memset(&opts, 0, sizeof(opts));
+	opts.head_idx = 1;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
+	opts.fn = oneway_merge;
+	opts.merge = 1;
+	if (!quiet)
+		opts.verbose_update = 1;
+	switch (reset_type) {
+	case MERGE:
+		opts.update = 1;
+		break;
+	case HARD:
+		opts.update = 1;
+		/* fallthrough */
+	default:
+		opts.reset = 1;
+	}
+
+	newfd = hold_locked_index(lock, 1);
+
+	read_cache_unmerged();
+
+	if (!fill_tree_descriptor(desc + nr - 1, sha1))
+		return error("Failed to find tree of %s.", sha1_to_hex(sha1));
+	if (unpack_trees(nr, desc, &opts))
+		return -1;
+	if (write_cache(newfd, active_cache, active_nr) ||
+	    commit_locked_index(lock))
+		return error("Could not write new index file.");
+
+	return 0;
+}
+
+static void print_new_head_line(struct commit *commit)
+{
+	const char *hex, *body;
+
+	hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
+	printf("HEAD is now at %s", hex);
+	body = strstr(commit->buffer, "\n\n");
+	if (body) {
+		const char *eol;
+		size_t len;
+		body += 2;
+		eol = strchr(body, '\n');
+		len = eol ? eol - body : strlen(body);
+		printf(" %.*s\n", (int) len, body);
+	}
+	else
+		printf("\n");
+}
+
+static int update_index_refresh(int fd, struct lock_file *index_lock, int flags)
+{
+	int result;
+
+	if (!index_lock) {
+		index_lock = xcalloc(1, sizeof(struct lock_file));
+		fd = hold_locked_index(index_lock, 1);
+	}
+
+	if (read_cache() < 0)
+		return error("Could not read index");
+
+	result = refresh_index(&the_index, (flags), NULL, NULL,
+			       "Unstaged changes after reset:") ? 1 : 0;
+	if (write_cache(fd, active_cache, active_nr) ||
+			commit_locked_index(index_lock))
+		return error ("Could not refresh index");
+	return result;
+}
+
+static void update_index_from_diff(struct diff_queue_struct *q,
+		struct diff_options *opt, void *data)
+{
+	int i;
+	int *discard_flag = data;
+
+	/* do_diff_cache() mangled the index */
+	discard_cache();
+	*discard_flag = 1;
+	read_cache();
+
+	for (i = 0; i < q->nr; i++) {
+		struct diff_filespec *one = q->queue[i]->one;
+		if (one->mode) {
+			struct cache_entry *ce;
+			ce = make_cache_entry(one->mode, one->sha1, one->path,
+				0, 0);
+			if (!ce)
+				die("make_cache_entry failed for path '%s'",
+				    one->path);
+			add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
+				ADD_CACHE_OK_TO_REPLACE);
+		} else
+			remove_file_from_cache(one->path);
+	}
+}
+
+static int interactive_reset(const char *revision, const char **argv,
+			     const char *prefix)
+{
+	const char **pathspec = NULL;
+
+	if (*argv)
+		pathspec = get_pathspec(prefix, argv);
+
+	return run_add_interactive(revision, "--patch=reset", pathspec);
+}
+
+static int read_from_tree(const char *prefix, const char **argv,
+		unsigned char *tree_sha1, int refresh_flags)
+{
+	struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+	int index_fd, index_was_discarded = 0;
+	struct diff_options opt;
+
+	memset(&opt, 0, sizeof(opt));
+	diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
+	opt.output_format = DIFF_FORMAT_CALLBACK;
+	opt.format_callback = update_index_from_diff;
+	opt.format_callback_data = &index_was_discarded;
+
+	index_fd = hold_locked_index(lock, 1);
+	index_was_discarded = 0;
+	read_cache();
+	if (do_diff_cache(tree_sha1, &opt))
+		return 1;
+	diffcore_std(&opt);
+	diff_flush(&opt);
+	diff_tree_release_paths(&opt);
+
+	if (!index_was_discarded)
+		/* The index is still clobbered from do_diff_cache() */
+		discard_cache();
+	return update_index_refresh(index_fd, lock, refresh_flags);
+}
+
+static void prepend_reflog_action(const char *action, char *buf, size_t size)
+{
+	const char *sep = ": ";
+	const char *rla = getenv("GIT_REFLOG_ACTION");
+	if (!rla)
+		rla = sep = "";
+	if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size)
+		warning("Reflog action message too long: %.*s...", 50, buf);
+}
+
+int cmd_reset(int argc, const char **argv, const char *prefix)
+{
+	int i = 0, reset_type = NONE, update_ref_status = 0, quiet = 0;
+	int patch_mode = 0;
+	const char *rev = "HEAD";
+	unsigned char sha1[20], *orig = NULL, sha1_orig[20],
+				*old_orig = NULL, sha1_old_orig[20];
+	struct commit *commit;
+	char *reflog_action, msg[1024];
+	const struct option options[] = {
+		OPT__QUIET(&quiet),
+		OPT_SET_INT(0, "mixed", &reset_type,
+						"reset HEAD and index", MIXED),
+		OPT_SET_INT(0, "soft", &reset_type, "reset only HEAD", SOFT),
+		OPT_SET_INT(0, "hard", &reset_type,
+				"reset HEAD, index and working tree", HARD),
+		OPT_SET_INT(0, "merge", &reset_type,
+				"reset HEAD, index and working tree", MERGE),
+		OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+
+	argc = parse_options(argc, argv, prefix, options, git_reset_usage,
+						PARSE_OPT_KEEP_DASHDASH);
+	reflog_action = args_to_str(argv);
+	setenv("GIT_REFLOG_ACTION", reflog_action, 0);
+
+	/*
+	 * Possible arguments are:
+	 *
+	 * git reset [-opts] <rev> <paths>...
+	 * git reset [-opts] <rev> -- <paths>...
+	 * git reset [-opts] -- <paths>...
+	 * git reset [-opts] <paths>...
+	 *
+	 * At this point, argv[i] points immediately after [-opts].
+	 */
+
+	if (i < argc) {
+		if (!strcmp(argv[i], "--")) {
+			i++; /* reset to HEAD, possibly with paths */
+		} else if (i + 1 < argc && !strcmp(argv[i+1], "--")) {
+			rev = argv[i];
+			i += 2;
+		}
+		/*
+		 * Otherwise, argv[i] could be either <rev> or <paths> and
+		 * has to be unambiguous.
+		 */
+		else if (!get_sha1(argv[i], sha1)) {
+			/*
+			 * Ok, argv[i] looks like a rev; it should not
+			 * be a filename.
+			 */
+			verify_non_filename(prefix, argv[i]);
+			rev = argv[i++];
+		} else {
+			/* Otherwise we treat this as a filename */
+			verify_filename(prefix, argv[i]);
+		}
+	}
+
+	if (get_sha1(rev, sha1))
+		die("Failed to resolve '%s' as a valid ref.", rev);
+
+	commit = lookup_commit_reference(sha1);
+	if (!commit)
+		die("Could not parse object '%s'.", rev);
+	hashcpy(sha1, commit->object.sha1);
+
+	if (patch_mode) {
+		if (reset_type != NONE)
+			die("--patch is incompatible with --{hard,mixed,soft}");
+		return interactive_reset(rev, argv + i, prefix);
+	}
+
+	/* git reset tree [--] paths... can be used to
+	 * load chosen paths from the tree into the index without
+	 * affecting the working tree nor HEAD. */
+	if (i < argc) {
+		if (reset_type == MIXED)
+			warning("--mixed option is deprecated with paths.");
+		else if (reset_type != NONE)
+			die("Cannot do %s reset with paths.",
+					reset_type_names[reset_type]);
+		return read_from_tree(prefix, argv + i, sha1,
+				quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
+	}
+	if (reset_type == NONE)
+		reset_type = MIXED; /* by default */
+
+	if (reset_type == HARD || reset_type == MERGE)
+		setup_work_tree();
+
+	if (reset_type == MIXED && is_bare_repository())
+		die("%s reset is not allowed in a bare repository",
+		    reset_type_names[reset_type]);
+
+	/* Soft reset does not touch the index file nor the working tree
+	 * at all, but requires them in a good order.  Other resets reset
+	 * the index file to the tree object we are switching to. */
+	if (reset_type == SOFT) {
+		if (is_merge() || read_cache() < 0 || unmerged_cache())
+			die("Cannot do a soft reset in the middle of a merge.");
+	}
+	else if (reset_index_file(sha1, reset_type, quiet))
+		die("Could not reset index file to revision '%s'.", rev);
+
+	/* Any resets update HEAD to the head being switched to,
+	 * saving the previous head in ORIG_HEAD before. */
+	if (!get_sha1("ORIG_HEAD", sha1_old_orig))
+		old_orig = sha1_old_orig;
+	if (!get_sha1("HEAD", sha1_orig)) {
+		orig = sha1_orig;
+		prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
+		update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
+	}
+	else if (old_orig)
+		delete_ref("ORIG_HEAD", old_orig, 0);
+	prepend_reflog_action("updating HEAD", msg, sizeof(msg));
+	update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR);
+
+	switch (reset_type) {
+	case HARD:
+		if (!update_ref_status && !quiet)
+			print_new_head_line(commit);
+		break;
+	case SOFT: /* Nothing else to do. */
+		break;
+	case MIXED: /* Report what has not been updated. */
+		update_index_refresh(0, NULL,
+				quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
+		break;
+	}
+
+	remove_branch_state();
+
+	free(reflog_action);
+
+	return update_ref_status;
+}
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
new file mode 100644
index 0000000..5679170
--- /dev/null
+++ b/builtin/rev-list.c
@@ -0,0 +1,401 @@
+#include "cache.h"
+#include "commit.h"
+#include "diff.h"
+#include "revision.h"
+#include "list-objects.h"
+#include "builtin.h"
+#include "log-tree.h"
+#include "graph.h"
+#include "bisect.h"
+
+static const char rev_list_usage[] =
+"git rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
+"  limiting output:\n"
+"    --max-count=nr\n"
+"    --max-age=epoch\n"
+"    --min-age=epoch\n"
+"    --sparse\n"
+"    --no-merges\n"
+"    --remove-empty\n"
+"    --all\n"
+"    --branches\n"
+"    --tags\n"
+"    --remotes\n"
+"    --stdin\n"
+"    --quiet\n"
+"  ordering output:\n"
+"    --topo-order\n"
+"    --date-order\n"
+"    --reverse\n"
+"  formatting output:\n"
+"    --parents\n"
+"    --children\n"
+"    --objects | --objects-edge\n"
+"    --unpacked\n"
+"    --header | --pretty\n"
+"    --abbrev=nr | --no-abbrev\n"
+"    --abbrev-commit\n"
+"    --left-right\n"
+"  special purpose:\n"
+"    --bisect\n"
+"    --bisect-vars\n"
+"    --bisect-all"
+;
+
+static void finish_commit(struct commit *commit, void *data);
+static void show_commit(struct commit *commit, void *data)
+{
+	struct rev_list_info *info = data;
+	struct rev_info *revs = info->revs;
+
+	graph_show_commit(revs->graph);
+
+	if (info->show_timestamp)
+		printf("%lu ", commit->date);
+	if (info->header_prefix)
+		fputs(info->header_prefix, stdout);
+
+	if (!revs->graph) {
+		if (commit->object.flags & BOUNDARY)
+			putchar('-');
+		else if (commit->object.flags & UNINTERESTING)
+			putchar('^');
+		else if (revs->left_right) {
+			if (commit->object.flags & SYMMETRIC_LEFT)
+				putchar('<');
+			else
+				putchar('>');
+		}
+	}
+	if (revs->abbrev_commit && revs->abbrev)
+		fputs(find_unique_abbrev(commit->object.sha1, revs->abbrev),
+		      stdout);
+	else
+		fputs(sha1_to_hex(commit->object.sha1), stdout);
+	if (revs->print_parents) {
+		struct commit_list *parents = commit->parents;
+		while (parents) {
+			printf(" %s", sha1_to_hex(parents->item->object.sha1));
+			parents = parents->next;
+		}
+	}
+	if (revs->children.name) {
+		struct commit_list *children;
+
+		children = lookup_decoration(&revs->children, &commit->object);
+		while (children) {
+			printf(" %s", sha1_to_hex(children->item->object.sha1));
+			children = children->next;
+		}
+	}
+	show_decorations(revs, commit);
+	if (revs->commit_format == CMIT_FMT_ONELINE)
+		putchar(' ');
+	else
+		putchar('\n');
+
+	if (revs->verbose_header && commit->buffer) {
+		struct strbuf buf = STRBUF_INIT;
+		struct pretty_print_context ctx = {0};
+		ctx.abbrev = revs->abbrev;
+		ctx.date_mode = revs->date_mode;
+		pretty_print_commit(revs->commit_format, commit, &buf, &ctx);
+		if (revs->graph) {
+			if (buf.len) {
+				if (revs->commit_format != CMIT_FMT_ONELINE)
+					graph_show_oneline(revs->graph);
+
+				graph_show_commit_msg(revs->graph, &buf);
+
+				/*
+				 * Add a newline after the commit message.
+				 *
+				 * Usually, this newline produces a blank
+				 * padding line between entries, in which case
+				 * we need to add graph padding on this line.
+				 *
+				 * However, the commit message may not end in a
+				 * newline.  In this case the newline simply
+				 * ends the last line of the commit message,
+				 * and we don't need any graph output.  (This
+				 * always happens with CMIT_FMT_ONELINE, and it
+				 * happens with CMIT_FMT_USERFORMAT when the
+				 * format doesn't explicitly end in a newline.)
+				 */
+				if (buf.len && buf.buf[buf.len - 1] == '\n')
+					graph_show_padding(revs->graph);
+				putchar('\n');
+			} else {
+				/*
+				 * If the message buffer is empty, just show
+				 * the rest of the graph output for this
+				 * commit.
+				 */
+				if (graph_show_remainder(revs->graph))
+					putchar('\n');
+			}
+		} else {
+			if (buf.len)
+				printf("%s%c", buf.buf, info->hdr_termination);
+		}
+		strbuf_release(&buf);
+	} else {
+		if (graph_show_remainder(revs->graph))
+			putchar('\n');
+	}
+	maybe_flush_or_die(stdout, "stdout");
+	finish_commit(commit, data);
+}
+
+static void finish_commit(struct commit *commit, void *data)
+{
+	if (commit->parents) {
+		free_commit_list(commit->parents);
+		commit->parents = NULL;
+	}
+	free(commit->buffer);
+	commit->buffer = NULL;
+}
+
+static void finish_object(struct object *obj, const struct name_path *path, const char *name)
+{
+	if (obj->type == OBJ_BLOB && !has_sha1_file(obj->sha1))
+		die("missing blob object '%s'", sha1_to_hex(obj->sha1));
+}
+
+static void show_object(struct object *obj, const struct name_path *path, const char *component)
+{
+	char *name = path_name(path, component);
+	/* An object with name "foo\n0000000..." can be used to
+	 * confuse downstream "git pack-objects" very badly.
+	 */
+	const char *ep = strchr(name, '\n');
+
+	finish_object(obj, path, name);
+	if (ep) {
+		printf("%s %.*s\n", sha1_to_hex(obj->sha1),
+		       (int) (ep - name),
+		       name);
+	}
+	else
+		printf("%s %s\n", sha1_to_hex(obj->sha1), name);
+	free(name);
+}
+
+static void show_edge(struct commit *commit)
+{
+	printf("-%s\n", sha1_to_hex(commit->object.sha1));
+}
+
+static inline int log2i(int n)
+{
+	int log2 = 0;
+
+	for (; n > 1; n >>= 1)
+		log2++;
+
+	return log2;
+}
+
+static inline int exp2i(int n)
+{
+	return 1 << n;
+}
+
+/*
+ * Estimate the number of bisect steps left (after the current step)
+ *
+ * For any x between 0 included and 2^n excluded, the probability for
+ * n - 1 steps left looks like:
+ *
+ * P(2^n + x) == (2^n - x) / (2^n + x)
+ *
+ * and P(2^n + x) < 0.5 means 2^n < 3x
+ */
+int estimate_bisect_steps(int all)
+{
+	int n, x, e;
+
+	if (all < 3)
+		return 0;
+
+	n = log2i(all);
+	e = exp2i(n);
+	x = all - e;
+
+	return (e < 3 * x) ? n : n - 1;
+}
+
+void print_commit_list(struct commit_list *list,
+		       const char *format_cur,
+		       const char *format_last)
+{
+	for ( ; list; list = list->next) {
+		const char *format = list->next ? format_cur : format_last;
+		printf(format, sha1_to_hex(list->item->object.sha1));
+	}
+}
+
+static void show_tried_revs(struct commit_list *tried)
+{
+	printf("bisect_tried='");
+	print_commit_list(tried, "%s|", "%s");
+	printf("'\n");
+}
+
+static void print_var_str(const char *var, const char *val)
+{
+	printf("%s='%s'\n", var, val);
+}
+
+static void print_var_int(const char *var, int val)
+{
+	printf("%s=%d\n", var, val);
+}
+
+static int show_bisect_vars(struct rev_list_info *info, int reaches, int all)
+{
+	int cnt, flags = info->bisect_show_flags;
+	char hex[41] = "";
+	struct commit_list *tried;
+	struct rev_info *revs = info->revs;
+
+	if (!revs->commits && !(flags & BISECT_SHOW_TRIED))
+		return 1;
+
+	revs->commits = filter_skipped(revs->commits, &tried,
+				       flags & BISECT_SHOW_ALL,
+				       NULL, NULL);
+
+	/*
+	 * revs->commits can reach "reaches" commits among
+	 * "all" commits.  If it is good, then there are
+	 * (all-reaches) commits left to be bisected.
+	 * On the other hand, if it is bad, then the set
+	 * to bisect is "reaches".
+	 * A bisect set of size N has (N-1) commits further
+	 * to test, as we already know one bad one.
+	 */
+	cnt = all - reaches;
+	if (cnt < reaches)
+		cnt = reaches;
+
+	if (revs->commits)
+		strcpy(hex, sha1_to_hex(revs->commits->item->object.sha1));
+
+	if (flags & BISECT_SHOW_ALL) {
+		traverse_commit_list(revs, show_commit, show_object, info);
+		printf("------\n");
+	}
+
+	if (flags & BISECT_SHOW_TRIED)
+		show_tried_revs(tried);
+
+	print_var_str("bisect_rev", hex);
+	print_var_int("bisect_nr", cnt - 1);
+	print_var_int("bisect_good", all - reaches - 1);
+	print_var_int("bisect_bad", reaches - 1);
+	print_var_int("bisect_all", all);
+	print_var_int("bisect_steps", estimate_bisect_steps(all));
+
+	return 0;
+}
+
+int cmd_rev_list(int argc, const char **argv, const char *prefix)
+{
+	struct rev_info revs;
+	struct rev_list_info info;
+	int i;
+	int bisect_list = 0;
+	int bisect_show_vars = 0;
+	int bisect_find_all = 0;
+	int quiet = 0;
+
+	git_config(git_default_config, NULL);
+	init_revisions(&revs, prefix);
+	revs.abbrev = 0;
+	revs.commit_format = CMIT_FMT_UNSPECIFIED;
+	argc = setup_revisions(argc, argv, &revs, NULL);
+
+	memset(&info, 0, sizeof(info));
+	info.revs = &revs;
+	if (revs.bisect)
+		bisect_list = 1;
+
+	quiet = DIFF_OPT_TST(&revs.diffopt, QUICK);
+	for (i = 1 ; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (!strcmp(arg, "--header")) {
+			revs.verbose_header = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--timestamp")) {
+			info.show_timestamp = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--bisect")) {
+			bisect_list = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--bisect-all")) {
+			bisect_list = 1;
+			bisect_find_all = 1;
+			info.bisect_show_flags = BISECT_SHOW_ALL;
+			revs.show_decorations = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--bisect-vars")) {
+			bisect_list = 1;
+			bisect_show_vars = 1;
+			continue;
+		}
+		usage(rev_list_usage);
+
+	}
+	if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
+		/* The command line has a --pretty  */
+		info.hdr_termination = '\n';
+		if (revs.commit_format == CMIT_FMT_ONELINE)
+			info.header_prefix = "";
+		else
+			info.header_prefix = "commit ";
+	}
+	else if (revs.verbose_header)
+		/* Only --header was specified */
+		revs.commit_format = CMIT_FMT_RAW;
+
+	if ((!revs.commits &&
+	     (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) &&
+	      !revs.pending.nr)) ||
+	    revs.diff)
+		usage(rev_list_usage);
+
+	save_commit_buffer = (revs.verbose_header ||
+			      revs.grep_filter.pattern_list ||
+			      revs.grep_filter.header_list);
+	if (bisect_list)
+		revs.limited = 1;
+
+	if (prepare_revision_walk(&revs))
+		die("revision walk setup failed");
+	if (revs.tree_objects)
+		mark_edges_uninteresting(revs.commits, &revs, show_edge);
+
+	if (bisect_list) {
+		int reaches = reaches, all = all;
+
+		revs.commits = find_bisection(revs.commits, &reaches, &all,
+					      bisect_find_all);
+
+		if (bisect_show_vars)
+			return show_bisect_vars(&info, reaches, all);
+	}
+
+	traverse_commit_list(&revs,
+			     quiet ? finish_commit : show_commit,
+			     quiet ? finish_object : show_object,
+			     &info);
+
+	return 0;
+}
diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
new file mode 100644
index 0000000..8fbf9d0
--- /dev/null
+++ b/builtin/rev-parse.c
@@ -0,0 +1,733 @@
+/*
+ * rev-parse.c
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "commit.h"
+#include "refs.h"
+#include "quote.h"
+#include "builtin.h"
+#include "parse-options.h"
+
+#define DO_REVS		1
+#define DO_NOREV	2
+#define DO_FLAGS	4
+#define DO_NONFLAGS	8
+static int filter = ~0;
+
+static const char *def;
+
+#define NORMAL 0
+#define REVERSED 1
+static int show_type = NORMAL;
+
+#define SHOW_SYMBOLIC_ASIS 1
+#define SHOW_SYMBOLIC_FULL 2
+static int symbolic;
+static int abbrev;
+static int abbrev_ref;
+static int abbrev_ref_strict;
+static int output_sq;
+
+/*
+ * Some arguments are relevant "revision" arguments,
+ * others are about output format or other details.
+ * This sorts it all out.
+ */
+static int is_rev_argument(const char *arg)
+{
+	static const char *rev_args[] = {
+		"--all",
+		"--bisect",
+		"--dense",
+		"--branches=",
+		"--branches",
+		"--header",
+		"--max-age=",
+		"--max-count=",
+		"--min-age=",
+		"--no-merges",
+		"--objects",
+		"--objects-edge",
+		"--parents",
+		"--pretty",
+		"--remotes=",
+		"--remotes",
+		"--glob=",
+		"--sparse",
+		"--tags=",
+		"--tags",
+		"--topo-order",
+		"--date-order",
+		"--unpacked",
+		NULL
+	};
+	const char **p = rev_args;
+
+	/* accept -<digit>, like traditional "head" */
+	if ((*arg == '-') && isdigit(arg[1]))
+		return 1;
+
+	for (;;) {
+		const char *str = *p++;
+		int len;
+		if (!str)
+			return 0;
+		len = strlen(str);
+		if (!strcmp(arg, str) ||
+		    (str[len-1] == '=' && !strncmp(arg, str, len)))
+			return 1;
+	}
+}
+
+/* Output argument as a string, either SQ or normal */
+static void show(const char *arg)
+{
+	if (output_sq) {
+		int sq = '\'', ch;
+
+		putchar(sq);
+		while ((ch = *arg++)) {
+			if (ch == sq)
+				fputs("'\\'", stdout);
+			putchar(ch);
+		}
+		putchar(sq);
+		putchar(' ');
+	}
+	else
+		puts(arg);
+}
+
+/* Like show(), but with a negation prefix according to type */
+static void show_with_type(int type, const char *arg)
+{
+	if (type != show_type)
+		putchar('^');
+	show(arg);
+}
+
+/* Output a revision, only if filter allows it */
+static void show_rev(int type, const unsigned char *sha1, const char *name)
+{
+	if (!(filter & DO_REVS))
+		return;
+	def = NULL;
+
+	if ((symbolic || abbrev_ref) && name) {
+		if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
+			unsigned char discard[20];
+			char *full;
+
+			switch (dwim_ref(name, strlen(name), discard, &full)) {
+			case 0:
+				/*
+				 * Not found -- not a ref.  We could
+				 * emit "name" here, but symbolic-full
+				 * users are interested in finding the
+				 * refs spelled in full, and they would
+				 * need to filter non-refs if we did so.
+				 */
+				break;
+			case 1: /* happy */
+				if (abbrev_ref)
+					full = shorten_unambiguous_ref(full,
+						abbrev_ref_strict);
+				show_with_type(type, full);
+				break;
+			default: /* ambiguous */
+				error("refname '%s' is ambiguous", name);
+				break;
+			}
+		} else {
+			show_with_type(type, name);
+		}
+	}
+	else if (abbrev)
+		show_with_type(type, find_unique_abbrev(sha1, abbrev));
+	else
+		show_with_type(type, sha1_to_hex(sha1));
+}
+
+/* Output a flag, only if filter allows it. */
+static int show_flag(const char *arg)
+{
+	if (!(filter & DO_FLAGS))
+		return 0;
+	if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
+		show(arg);
+		return 1;
+	}
+	return 0;
+}
+
+static int show_default(void)
+{
+	const char *s = def;
+
+	if (s) {
+		unsigned char sha1[20];
+
+		def = NULL;
+		if (!get_sha1(s, sha1)) {
+			show_rev(NORMAL, sha1, s);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static int show_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	show_rev(NORMAL, sha1, refname);
+	return 0;
+}
+
+static int anti_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	show_rev(REVERSED, sha1, refname);
+	return 0;
+}
+
+static void show_datestring(const char *flag, const char *datestr)
+{
+	static char buffer[100];
+
+	/* date handling requires both flags and revs */
+	if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
+		return;
+	snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
+	show(buffer);
+}
+
+static int show_file(const char *arg)
+{
+	show_default();
+	if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
+		show(arg);
+		return 1;
+	}
+	return 0;
+}
+
+static int try_difference(const char *arg)
+{
+	char *dotdot;
+	unsigned char sha1[20];
+	unsigned char end[20];
+	const char *next;
+	const char *this;
+	int symmetric;
+
+	if (!(dotdot = strstr(arg, "..")))
+		return 0;
+	next = dotdot + 2;
+	this = arg;
+	symmetric = (*next == '.');
+
+	*dotdot = 0;
+	next += symmetric;
+
+	if (!*next)
+		next = "HEAD";
+	if (dotdot == arg)
+		this = "HEAD";
+	if (!get_sha1(this, sha1) && !get_sha1(next, end)) {
+		show_rev(NORMAL, end, next);
+		show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
+		if (symmetric) {
+			struct commit_list *exclude;
+			struct commit *a, *b;
+			a = lookup_commit_reference(sha1);
+			b = lookup_commit_reference(end);
+			exclude = get_merge_bases(a, b, 1);
+			while (exclude) {
+				struct commit_list *n = exclude->next;
+				show_rev(REVERSED,
+					 exclude->item->object.sha1,NULL);
+				free(exclude);
+				exclude = n;
+			}
+		}
+		return 1;
+	}
+	*dotdot = '.';
+	return 0;
+}
+
+static int try_parent_shorthands(const char *arg)
+{
+	char *dotdot;
+	unsigned char sha1[20];
+	struct commit *commit;
+	struct commit_list *parents;
+	int parents_only;
+
+	if ((dotdot = strstr(arg, "^!")))
+		parents_only = 0;
+	else if ((dotdot = strstr(arg, "^@")))
+		parents_only = 1;
+
+	if (!dotdot || dotdot[2])
+		return 0;
+
+	*dotdot = 0;
+	if (get_sha1(arg, sha1))
+		return 0;
+
+	if (!parents_only)
+		show_rev(NORMAL, sha1, arg);
+	commit = lookup_commit_reference(sha1);
+	for (parents = commit->parents; parents; parents = parents->next)
+		show_rev(parents_only ? NORMAL : REVERSED,
+				parents->item->object.sha1, arg);
+
+	return 1;
+}
+
+static int parseopt_dump(const struct option *o, const char *arg, int unset)
+{
+	struct strbuf *parsed = o->value;
+	if (unset)
+		strbuf_addf(parsed, " --no-%s", o->long_name);
+	else if (o->short_name)
+		strbuf_addf(parsed, " -%c", o->short_name);
+	else
+		strbuf_addf(parsed, " --%s", o->long_name);
+	if (arg) {
+		strbuf_addch(parsed, ' ');
+		sq_quote_buf(parsed, arg);
+	}
+	return 0;
+}
+
+static const char *skipspaces(const char *s)
+{
+	while (isspace(*s))
+		s++;
+	return s;
+}
+
+static int cmd_parseopt(int argc, const char **argv, const char *prefix)
+{
+	static int keep_dashdash = 0, stop_at_non_option = 0;
+	static char const * const parseopt_usage[] = {
+		"git rev-parse --parseopt [options] -- [<args>...]",
+		NULL
+	};
+	static struct option parseopt_opts[] = {
+		OPT_BOOLEAN(0, "keep-dashdash", &keep_dashdash,
+					"keep the `--` passed as an arg"),
+		OPT_BOOLEAN(0, "stop-at-non-option", &stop_at_non_option,
+					"stop parsing after the "
+					"first non-option argument"),
+		OPT_END(),
+	};
+
+	struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
+	const char **usage = NULL;
+	struct option *opts = NULL;
+	int onb = 0, osz = 0, unb = 0, usz = 0;
+
+	strbuf_addstr(&parsed, "set --");
+	argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
+	                     PARSE_OPT_KEEP_DASHDASH);
+	if (argc < 1 || strcmp(argv[0], "--"))
+		usage_with_options(parseopt_usage, parseopt_opts);
+
+	/* get the usage up to the first line with a -- on it */
+	for (;;) {
+		if (strbuf_getline(&sb, stdin, '\n') == EOF)
+			die("premature end of input");
+		ALLOC_GROW(usage, unb + 1, usz);
+		if (!strcmp("--", sb.buf)) {
+			if (unb < 1)
+				die("no usage string given before the `--' separator");
+			usage[unb] = NULL;
+			break;
+		}
+		usage[unb++] = strbuf_detach(&sb, NULL);
+	}
+
+	/* parse: (<short>|<short>,<long>|<long>)[=?]? SP+ <help> */
+	while (strbuf_getline(&sb, stdin, '\n') != EOF) {
+		const char *s;
+		struct option *o;
+
+		if (!sb.len)
+			continue;
+
+		ALLOC_GROW(opts, onb + 1, osz);
+		memset(opts + onb, 0, sizeof(opts[onb]));
+
+		o = &opts[onb++];
+		s = strchr(sb.buf, ' ');
+		if (!s || *sb.buf == ' ') {
+			o->type = OPTION_GROUP;
+			o->help = xstrdup(skipspaces(sb.buf));
+			continue;
+		}
+
+		o->type = OPTION_CALLBACK;
+		o->help = xstrdup(skipspaces(s));
+		o->value = &parsed;
+		o->flags = PARSE_OPT_NOARG;
+		o->callback = &parseopt_dump;
+		while (s > sb.buf && strchr("*=?!", s[-1])) {
+			switch (*--s) {
+			case '=':
+				o->flags &= ~PARSE_OPT_NOARG;
+				break;
+			case '?':
+				o->flags &= ~PARSE_OPT_NOARG;
+				o->flags |= PARSE_OPT_OPTARG;
+				break;
+			case '!':
+				o->flags |= PARSE_OPT_NONEG;
+				break;
+			case '*':
+				o->flags |= PARSE_OPT_HIDDEN;
+				break;
+			}
+		}
+
+		if (s - sb.buf == 1) /* short option only */
+			o->short_name = *sb.buf;
+		else if (sb.buf[1] != ',') /* long option only */
+			o->long_name = xmemdupz(sb.buf, s - sb.buf);
+		else {
+			o->short_name = *sb.buf;
+			o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
+		}
+	}
+	strbuf_release(&sb);
+
+	/* put an OPT_END() */
+	ALLOC_GROW(opts, onb + 1, osz);
+	memset(opts + onb, 0, sizeof(opts[onb]));
+	argc = parse_options(argc, argv, prefix, opts, usage,
+			keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0 |
+			stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0);
+
+	strbuf_addf(&parsed, " --");
+	sq_quote_argv(&parsed, argv, 0);
+	puts(parsed.buf);
+	return 0;
+}
+
+static int cmd_sq_quote(int argc, const char **argv)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	if (argc)
+		sq_quote_argv(&buf, argv, 0);
+	printf("%s\n", buf.buf);
+	strbuf_release(&buf);
+
+	return 0;
+}
+
+static void die_no_single_rev(int quiet)
+{
+	if (quiet)
+		exit(1);
+	else
+		die("Needed a single revision");
+}
+
+static const char builtin_rev_parse_usage[] =
+"git rev-parse --parseopt [options] -- [<args>...]\n"
+"   or: git rev-parse --sq-quote [<arg>...]\n"
+"   or: git rev-parse [options] [<arg>...]\n"
+"\n"
+"Run \"git rev-parse --parseopt -h\" for more information on the first usage.";
+
+int cmd_rev_parse(int argc, const char **argv, const char *prefix)
+{
+	int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
+	unsigned char sha1[20];
+	const char *name = NULL;
+
+	if (argc > 1 && !strcmp("--parseopt", argv[1]))
+		return cmd_parseopt(argc - 1, argv + 1, prefix);
+
+	if (argc > 1 && !strcmp("--sq-quote", argv[1]))
+		return cmd_sq_quote(argc - 2, argv + 2);
+
+	if (argc == 2 && !strcmp("--local-env-vars", argv[1])) {
+		int i;
+		for (i = 0; local_repo_env[i]; i++)
+			printf("%s\n", local_repo_env[i]);
+		return 0;
+	}
+
+	if (argc > 1 && !strcmp("-h", argv[1]))
+		usage(builtin_rev_parse_usage);
+
+	prefix = setup_git_directory();
+	git_config(git_default_config, NULL);
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (as_is) {
+			if (show_file(arg) && as_is < 2)
+				verify_filename(prefix, arg);
+			continue;
+		}
+		if (!strcmp(arg,"-n")) {
+			if (++i >= argc)
+				die("-n requires an argument");
+			if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
+				show(arg);
+				show(argv[i]);
+			}
+			continue;
+		}
+		if (!prefixcmp(arg, "-n")) {
+			if ((filter & DO_FLAGS) && (filter & DO_REVS))
+				show(arg);
+			continue;
+		}
+
+		if (*arg == '-') {
+			if (!strcmp(arg, "--")) {
+				as_is = 2;
+				/* Pass on the "--" if we show anything but files.. */
+				if (filter & (DO_FLAGS | DO_REVS))
+					show_file(arg);
+				continue;
+			}
+			if (!strcmp(arg, "--default")) {
+				def = argv[i+1];
+				i++;
+				continue;
+			}
+			if (!strcmp(arg, "--revs-only")) {
+				filter &= ~DO_NOREV;
+				continue;
+			}
+			if (!strcmp(arg, "--no-revs")) {
+				filter &= ~DO_REVS;
+				continue;
+			}
+			if (!strcmp(arg, "--flags")) {
+				filter &= ~DO_NONFLAGS;
+				continue;
+			}
+			if (!strcmp(arg, "--no-flags")) {
+				filter &= ~DO_FLAGS;
+				continue;
+			}
+			if (!strcmp(arg, "--verify")) {
+				filter &= ~(DO_FLAGS|DO_NOREV);
+				verify = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
+				quiet = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--short") ||
+			    !prefixcmp(arg, "--short=")) {
+				filter &= ~(DO_FLAGS|DO_NOREV);
+				verify = 1;
+				abbrev = DEFAULT_ABBREV;
+				if (arg[7] == '=')
+					abbrev = strtoul(arg + 8, NULL, 10);
+				if (abbrev < MINIMUM_ABBREV)
+					abbrev = MINIMUM_ABBREV;
+				else if (40 <= abbrev)
+					abbrev = 40;
+				continue;
+			}
+			if (!strcmp(arg, "--sq")) {
+				output_sq = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--not")) {
+				show_type ^= REVERSED;
+				continue;
+			}
+			if (!strcmp(arg, "--symbolic")) {
+				symbolic = SHOW_SYMBOLIC_ASIS;
+				continue;
+			}
+			if (!strcmp(arg, "--symbolic-full-name")) {
+				symbolic = SHOW_SYMBOLIC_FULL;
+				continue;
+			}
+			if (!prefixcmp(arg, "--abbrev-ref") &&
+			    (!arg[12] || arg[12] == '=')) {
+				abbrev_ref = 1;
+				abbrev_ref_strict = warn_ambiguous_refs;
+				if (arg[12] == '=') {
+					if (!strcmp(arg + 13, "strict"))
+						abbrev_ref_strict = 1;
+					else if (!strcmp(arg + 13, "loose"))
+						abbrev_ref_strict = 0;
+					else
+						die("unknown mode for %s", arg);
+				}
+				continue;
+			}
+			if (!strcmp(arg, "--all")) {
+				for_each_ref(show_reference, NULL);
+				continue;
+			}
+			if (!strcmp(arg, "--bisect")) {
+				for_each_ref_in("refs/bisect/bad", show_reference, NULL);
+				for_each_ref_in("refs/bisect/good", anti_reference, NULL);
+				continue;
+			}
+			if (!prefixcmp(arg, "--branches=")) {
+				for_each_glob_ref_in(show_reference, arg + 11,
+					"refs/heads/", NULL);
+				continue;
+			}
+			if (!strcmp(arg, "--branches")) {
+				for_each_branch_ref(show_reference, NULL);
+				continue;
+			}
+			if (!prefixcmp(arg, "--tags=")) {
+				for_each_glob_ref_in(show_reference, arg + 7,
+					"refs/tags/", NULL);
+				continue;
+			}
+			if (!strcmp(arg, "--tags")) {
+				for_each_tag_ref(show_reference, NULL);
+				continue;
+			}
+			if (!prefixcmp(arg, "--glob=")) {
+				for_each_glob_ref(show_reference, arg + 7, NULL);
+				continue;
+			}
+			if (!prefixcmp(arg, "--remotes=")) {
+				for_each_glob_ref_in(show_reference, arg + 10,
+					"refs/remotes/", NULL);
+				continue;
+			}
+			if (!strcmp(arg, "--remotes")) {
+				for_each_remote_ref(show_reference, NULL);
+				continue;
+			}
+			if (!strcmp(arg, "--show-toplevel")) {
+				const char *work_tree = get_git_work_tree();
+				if (work_tree)
+					puts(work_tree);
+				continue;
+			}
+			if (!strcmp(arg, "--show-prefix")) {
+				if (prefix)
+					puts(prefix);
+				continue;
+			}
+			if (!strcmp(arg, "--show-cdup")) {
+				const char *pfx = prefix;
+				if (!is_inside_work_tree()) {
+					const char *work_tree =
+						get_git_work_tree();
+					if (work_tree)
+						printf("%s\n", work_tree);
+					continue;
+				}
+				while (pfx) {
+					pfx = strchr(pfx, '/');
+					if (pfx) {
+						pfx++;
+						printf("../");
+					}
+				}
+				putchar('\n');
+				continue;
+			}
+			if (!strcmp(arg, "--git-dir")) {
+				const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
+				static char cwd[PATH_MAX];
+				int len;
+				if (gitdir) {
+					puts(gitdir);
+					continue;
+				}
+				if (!prefix) {
+					puts(".git");
+					continue;
+				}
+				if (!getcwd(cwd, PATH_MAX))
+					die_errno("unable to get current working directory");
+				len = strlen(cwd);
+				printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
+				continue;
+			}
+			if (!strcmp(arg, "--is-inside-git-dir")) {
+				printf("%s\n", is_inside_git_dir() ? "true"
+						: "false");
+				continue;
+			}
+			if (!strcmp(arg, "--is-inside-work-tree")) {
+				printf("%s\n", is_inside_work_tree() ? "true"
+						: "false");
+				continue;
+			}
+			if (!strcmp(arg, "--is-bare-repository")) {
+				printf("%s\n", is_bare_repository() ? "true"
+						: "false");
+				continue;
+			}
+			if (!prefixcmp(arg, "--since=")) {
+				show_datestring("--max-age=", arg+8);
+				continue;
+			}
+			if (!prefixcmp(arg, "--after=")) {
+				show_datestring("--max-age=", arg+8);
+				continue;
+			}
+			if (!prefixcmp(arg, "--before=")) {
+				show_datestring("--min-age=", arg+9);
+				continue;
+			}
+			if (!prefixcmp(arg, "--until=")) {
+				show_datestring("--min-age=", arg+8);
+				continue;
+			}
+			if (show_flag(arg) && verify)
+				die_no_single_rev(quiet);
+			continue;
+		}
+
+		/* Not a flag argument */
+		if (try_difference(arg))
+			continue;
+		if (try_parent_shorthands(arg))
+			continue;
+		name = arg;
+		type = NORMAL;
+		if (*arg == '^') {
+			name++;
+			type = REVERSED;
+		}
+		if (!get_sha1(name, sha1)) {
+			if (verify)
+				revs_count++;
+			else
+				show_rev(type, sha1, name);
+			continue;
+		}
+		if (verify)
+			die_no_single_rev(quiet);
+		as_is = 1;
+		if (!show_file(arg))
+			continue;
+		verify_filename(prefix, arg);
+	}
+	if (verify) {
+		if (revs_count == 1) {
+			show_rev(type, sha1, name);
+			return 0;
+		} else if (revs_count == 0 && show_default())
+			return 0;
+		die_no_single_rev(quiet);
+	} else
+		show_default();
+	return 0;
+}
diff --git a/builtin/revert.c b/builtin/revert.c
new file mode 100644
index 0000000..eff5268
--- /dev/null
+++ b/builtin/revert.c
@@ -0,0 +1,460 @@
+#include "cache.h"
+#include "builtin.h"
+#include "object.h"
+#include "commit.h"
+#include "tag.h"
+#include "wt-status.h"
+#include "run-command.h"
+#include "exec_cmd.h"
+#include "utf8.h"
+#include "parse-options.h"
+#include "cache-tree.h"
+#include "diff.h"
+#include "revision.h"
+#include "rerere.h"
+#include "merge-recursive.h"
+
+/*
+ * This implements the builtins revert and cherry-pick.
+ *
+ * Copyright (c) 2007 Johannes E. Schindelin
+ *
+ * Based on git-revert.sh, which is
+ *
+ * Copyright (c) 2005 Linus Torvalds
+ * Copyright (c) 2005 Junio C Hamano
+ */
+
+static const char * const revert_usage[] = {
+	"git revert [options] <commit-ish>",
+	NULL
+};
+
+static const char * const cherry_pick_usage[] = {
+	"git cherry-pick [options] <commit-ish>",
+	NULL
+};
+
+static int edit, no_replay, no_commit, mainline, signoff;
+static enum { REVERT, CHERRY_PICK } action;
+static struct commit *commit;
+static const char *commit_name;
+static int allow_rerere_auto;
+
+static const char *me;
+
+#define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
+
+static void parse_args(int argc, const char **argv)
+{
+	const char * const * usage_str =
+		action == REVERT ?  revert_usage : cherry_pick_usage;
+	unsigned char sha1[20];
+	int noop;
+	struct option options[] = {
+		OPT_BOOLEAN('n', "no-commit", &no_commit, "don't automatically commit"),
+		OPT_BOOLEAN('e', "edit", &edit, "edit the commit message"),
+		OPT_BOOLEAN('x', NULL, &no_replay, "append commit name when cherry-picking"),
+		OPT_BOOLEAN('r', NULL, &noop, "no-op (backward compatibility)"),
+		OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
+		OPT_INTEGER('m', "mainline", &mainline, "parent number"),
+		OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
+		OPT_END(),
+	};
+
+	if (parse_options(argc, argv, NULL, options, usage_str, 0) != 1)
+		usage_with_options(usage_str, options);
+
+	commit_name = argv[0];
+	if (get_sha1(commit_name, sha1))
+		die ("Cannot find '%s'", commit_name);
+	commit = lookup_commit_reference(sha1);
+	if (!commit)
+		exit(1);
+}
+
+static char *get_oneline(const char *message)
+{
+	char *result;
+	const char *p = message, *abbrev, *eol;
+	int abbrev_len, oneline_len;
+
+	if (!p)
+		die ("Could not read commit message of %s",
+				sha1_to_hex(commit->object.sha1));
+	while (*p && (*p != '\n' || p[1] != '\n'))
+		p++;
+
+	if (*p) {
+		p += 2;
+		for (eol = p + 1; *eol && *eol != '\n'; eol++)
+			; /* do nothing */
+	} else
+		eol = p;
+	abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
+	abbrev_len = strlen(abbrev);
+	oneline_len = eol - p;
+	result = xmalloc(abbrev_len + 5 + oneline_len);
+	memcpy(result, abbrev, abbrev_len);
+	memcpy(result + abbrev_len, "... ", 4);
+	memcpy(result + abbrev_len + 4, p, oneline_len);
+	result[abbrev_len + 4 + oneline_len] = '\0';
+	return result;
+}
+
+static char *get_encoding(const char *message)
+{
+	const char *p = message, *eol;
+
+	if (!p)
+		die ("Could not read commit message of %s",
+				sha1_to_hex(commit->object.sha1));
+	while (*p && *p != '\n') {
+		for (eol = p + 1; *eol && *eol != '\n'; eol++)
+			; /* do nothing */
+		if (!prefixcmp(p, "encoding ")) {
+			char *result = xmalloc(eol - 8 - p);
+			strlcpy(result, p + 9, eol - 8 - p);
+			return result;
+		}
+		p = eol;
+		if (*p == '\n')
+			p++;
+	}
+	return NULL;
+}
+
+static struct lock_file msg_file;
+static int msg_fd;
+
+static void add_to_msg(const char *string)
+{
+	int len = strlen(string);
+	if (write_in_full(msg_fd, string, len) < 0)
+		die_errno ("Could not write to MERGE_MSG");
+}
+
+static void add_message_to_msg(const char *message)
+{
+	const char *p = message;
+	while (*p && (*p != '\n' || p[1] != '\n'))
+		p++;
+
+	if (!*p)
+		add_to_msg(sha1_to_hex(commit->object.sha1));
+
+	p += 2;
+	add_to_msg(p);
+	return;
+}
+
+static void set_author_ident_env(const char *message)
+{
+	const char *p = message;
+	if (!p)
+		die ("Could not read commit message of %s",
+				sha1_to_hex(commit->object.sha1));
+	while (*p && *p != '\n') {
+		const char *eol;
+
+		for (eol = p; *eol && *eol != '\n'; eol++)
+			; /* do nothing */
+		if (!prefixcmp(p, "author ")) {
+			char *line, *pend, *email, *timestamp;
+
+			p += 7;
+			line = xmemdupz(p, eol - p);
+			email = strchr(line, '<');
+			if (!email)
+				die ("Could not extract author email from %s",
+					sha1_to_hex(commit->object.sha1));
+			if (email == line)
+				pend = line;
+			else
+				for (pend = email; pend != line + 1 &&
+						isspace(pend[-1]); pend--);
+					; /* do nothing */
+			*pend = '\0';
+			email++;
+			timestamp = strchr(email, '>');
+			if (!timestamp)
+				die ("Could not extract author time from %s",
+					sha1_to_hex(commit->object.sha1));
+			*timestamp = '\0';
+			for (timestamp++; *timestamp && isspace(*timestamp);
+					timestamp++)
+				; /* do nothing */
+			setenv("GIT_AUTHOR_NAME", line, 1);
+			setenv("GIT_AUTHOR_EMAIL", email, 1);
+			setenv("GIT_AUTHOR_DATE", timestamp, 1);
+			free(line);
+			return;
+		}
+		p = eol;
+		if (*p == '\n')
+			p++;
+	}
+	die ("No author information found in %s",
+			sha1_to_hex(commit->object.sha1));
+}
+
+static char *help_msg(const char *name)
+{
+	struct strbuf helpbuf = STRBUF_INIT;
+	char *msg = getenv("GIT_CHERRY_PICK_HELP");
+
+	if (msg)
+		return msg;
+
+	strbuf_addstr(&helpbuf, "  After resolving the conflicts,\n"
+		"mark the corrected paths with 'git add <paths>' or 'git rm <paths>'\n"
+		"and commit the result");
+
+	if (action == CHERRY_PICK) {
+		strbuf_addf(&helpbuf, " with: \n"
+			"\n"
+			"        git commit -c %s\n",
+			name);
+	}
+	else
+		strbuf_addch(&helpbuf, '.');
+	return strbuf_detach(&helpbuf, NULL);
+}
+
+static struct tree *empty_tree(void)
+{
+	struct tree *tree = xcalloc(1, sizeof(struct tree));
+
+	tree->object.parsed = 1;
+	tree->object.type = OBJ_TREE;
+	pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
+	return tree;
+}
+
+static NORETURN void die_dirty_index(const char *me)
+{
+	if (read_cache_unmerged()) {
+		die_resolve_conflict(me);
+	} else {
+		if (advice_commit_before_merge)
+			die("Your local changes would be overwritten by %s.\n"
+			    "Please, commit your changes or stash them to proceed.", me);
+		else
+			die("Your local changes would be overwritten by %s.\n", me);
+	}
+}
+
+static int revert_or_cherry_pick(int argc, const char **argv)
+{
+	unsigned char head[20];
+	struct commit *base, *next, *parent;
+	int i, index_fd, clean;
+	char *oneline, *reencoded_message = NULL;
+	const char *message, *encoding;
+	char *defmsg = git_pathdup("MERGE_MSG");
+	struct merge_options o;
+	struct tree *result, *next_tree, *base_tree, *head_tree;
+	static struct lock_file index_lock;
+
+	git_config(git_default_config, NULL);
+	me = action == REVERT ? "revert" : "cherry-pick";
+	setenv(GIT_REFLOG_ACTION, me, 0);
+	parse_args(argc, argv);
+
+	/* this is copied from the shell script, but it's never triggered... */
+	if (action == REVERT && !no_replay)
+		die("revert is incompatible with replay");
+
+	if (read_cache() < 0)
+		die("git %s: failed to read the index", me);
+	if (no_commit) {
+		/*
+		 * We do not intend to commit immediately.  We just want to
+		 * merge the differences in, so let's compute the tree
+		 * that represents the "current" state for merge-recursive
+		 * to work on.
+		 */
+		if (write_cache_as_tree(head, 0, NULL))
+			die ("Your index file is unmerged.");
+	} else {
+		if (get_sha1("HEAD", head))
+			die ("You do not have a valid HEAD");
+		if (index_differs_from("HEAD", 0))
+			die_dirty_index(me);
+	}
+	discard_cache();
+
+	index_fd = hold_locked_index(&index_lock, 1);
+
+	if (!commit->parents) {
+		if (action == REVERT)
+			die ("Cannot revert a root commit");
+		parent = NULL;
+	}
+	else if (commit->parents->next) {
+		/* Reverting or cherry-picking a merge commit */
+		int cnt;
+		struct commit_list *p;
+
+		if (!mainline)
+			die("Commit %s is a merge but no -m option was given.",
+			    sha1_to_hex(commit->object.sha1));
+
+		for (cnt = 1, p = commit->parents;
+		     cnt != mainline && p;
+		     cnt++)
+			p = p->next;
+		if (cnt != mainline || !p)
+			die("Commit %s does not have parent %d",
+			    sha1_to_hex(commit->object.sha1), mainline);
+		parent = p->item;
+	} else if (0 < mainline)
+		die("Mainline was specified but commit %s is not a merge.",
+		    sha1_to_hex(commit->object.sha1));
+	else
+		parent = commit->parents->item;
+
+	if (!(message = commit->buffer))
+		die ("Cannot get commit message for %s",
+				sha1_to_hex(commit->object.sha1));
+
+	if (parent && parse_commit(parent) < 0)
+		die("%s: cannot parse parent commit %s",
+		    me, sha1_to_hex(parent->object.sha1));
+
+	/*
+	 * "commit" is an existing commit.  We would want to apply
+	 * the difference it introduces since its first parent "prev"
+	 * on top of the current HEAD if we are cherry-pick.  Or the
+	 * reverse of it if we are revert.
+	 */
+
+	msg_fd = hold_lock_file_for_update(&msg_file, defmsg,
+					   LOCK_DIE_ON_ERROR);
+
+	encoding = get_encoding(message);
+	if (!encoding)
+		encoding = "UTF-8";
+	if (!git_commit_encoding)
+		git_commit_encoding = "UTF-8";
+	if ((reencoded_message = reencode_string(message,
+					git_commit_encoding, encoding)))
+		message = reencoded_message;
+
+	oneline = get_oneline(message);
+
+	if (action == REVERT) {
+		char *oneline_body = strchr(oneline, ' ');
+
+		base = commit;
+		next = parent;
+		add_to_msg("Revert \"");
+		add_to_msg(oneline_body + 1);
+		add_to_msg("\"\n\nThis reverts commit ");
+		add_to_msg(sha1_to_hex(commit->object.sha1));
+
+		if (commit->parents->next) {
+			add_to_msg(", reversing\nchanges made to ");
+			add_to_msg(sha1_to_hex(parent->object.sha1));
+		}
+		add_to_msg(".\n");
+	} else {
+		base = parent;
+		next = commit;
+		set_author_ident_env(message);
+		add_message_to_msg(message);
+		if (no_replay) {
+			add_to_msg("(cherry picked from commit ");
+			add_to_msg(sha1_to_hex(commit->object.sha1));
+			add_to_msg(")\n");
+		}
+	}
+
+	read_cache();
+	init_merge_options(&o);
+	o.branch1 = "HEAD";
+	o.branch2 = oneline;
+
+	head_tree = parse_tree_indirect(head);
+	next_tree = next ? next->tree : empty_tree();
+	base_tree = base ? base->tree : empty_tree();
+
+	clean = merge_trees(&o,
+			    head_tree,
+			    next_tree, base_tree, &result);
+
+	if (active_cache_changed &&
+	    (write_cache(index_fd, active_cache, active_nr) ||
+	     commit_locked_index(&index_lock)))
+		die("%s: Unable to write new index file", me);
+	rollback_lock_file(&index_lock);
+
+	if (!clean) {
+		add_to_msg("\nConflicts:\n\n");
+		for (i = 0; i < active_nr;) {
+			struct cache_entry *ce = active_cache[i++];
+			if (ce_stage(ce)) {
+				add_to_msg("\t");
+				add_to_msg(ce->name);
+				add_to_msg("\n");
+				while (i < active_nr && !strcmp(ce->name,
+						active_cache[i]->name))
+					i++;
+			}
+		}
+		if (commit_lock_file(&msg_file) < 0)
+			die ("Error wrapping up %s", defmsg);
+		fprintf(stderr, "Automatic %s failed.%s\n",
+			me, help_msg(commit_name));
+		rerere(allow_rerere_auto);
+		exit(1);
+	}
+	if (commit_lock_file(&msg_file) < 0)
+		die ("Error wrapping up %s", defmsg);
+	fprintf(stderr, "Finished one %s.\n", me);
+
+	/*
+	 *
+	 * If we are cherry-pick, and if the merge did not result in
+	 * hand-editing, we will hit this commit and inherit the original
+	 * author date and name.
+	 * If we are revert, or if our cherry-pick results in a hand merge,
+	 * we had better say that the current user is responsible for that.
+	 */
+
+	if (!no_commit) {
+		/* 6 is max possible length of our args array including NULL */
+		const char *args[6];
+		int i = 0;
+		args[i++] = "commit";
+		args[i++] = "-n";
+		if (signoff)
+			args[i++] = "-s";
+		if (!edit) {
+			args[i++] = "-F";
+			args[i++] = defmsg;
+		}
+		args[i] = NULL;
+		return execv_git_cmd(args);
+	}
+	free(reencoded_message);
+	free(defmsg);
+
+	return 0;
+}
+
+int cmd_revert(int argc, const char **argv, const char *prefix)
+{
+	if (isatty(0))
+		edit = 1;
+	no_replay = 1;
+	action = REVERT;
+	return revert_or_cherry_pick(argc, argv);
+}
+
+int cmd_cherry_pick(int argc, const char **argv, const char *prefix)
+{
+	no_replay = 0;
+	action = CHERRY_PICK;
+	return revert_or_cherry_pick(argc, argv);
+}
diff --git a/builtin/rm.c b/builtin/rm.c
new file mode 100644
index 0000000..f3772c8
--- /dev/null
+++ b/builtin/rm.c
@@ -0,0 +1,272 @@
+/*
+ * "git rm" builtin command
+ *
+ * Copyright (C) Linus Torvalds 2006
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "dir.h"
+#include "cache-tree.h"
+#include "tree-walk.h"
+#include "parse-options.h"
+
+static const char * const builtin_rm_usage[] = {
+	"git rm [options] [--] <file>...",
+	NULL
+};
+
+static struct {
+	int nr, alloc;
+	const char **name;
+} list;
+
+static void add_list(const char *name)
+{
+	if (list.nr >= list.alloc) {
+		list.alloc = alloc_nr(list.alloc);
+		list.name = xrealloc(list.name, list.alloc * sizeof(const char *));
+	}
+	list.name[list.nr++] = name;
+}
+
+static int check_local_mod(unsigned char *head, int index_only)
+{
+	/*
+	 * Items in list are already sorted in the cache order,
+	 * so we could do this a lot more efficiently by using
+	 * tree_desc based traversal if we wanted to, but I am
+	 * lazy, and who cares if removal of files is a tad
+	 * slower than the theoretical maximum speed?
+	 */
+	int i, no_head;
+	int errs = 0;
+
+	no_head = is_null_sha1(head);
+	for (i = 0; i < list.nr; i++) {
+		struct stat st;
+		int pos;
+		struct cache_entry *ce;
+		const char *name = list.name[i];
+		unsigned char sha1[20];
+		unsigned mode;
+		int local_changes = 0;
+		int staged_changes = 0;
+
+		pos = cache_name_pos(name, strlen(name));
+		if (pos < 0)
+			continue; /* removing unmerged entry */
+		ce = active_cache[pos];
+
+		if (lstat(ce->name, &st) < 0) {
+			if (errno != ENOENT)
+				warning("'%s': %s", ce->name, strerror(errno));
+			/* It already vanished from the working tree */
+			continue;
+		}
+		else if (S_ISDIR(st.st_mode)) {
+			/* if a file was removed and it is now a
+			 * directory, that is the same as ENOENT as
+			 * far as git is concerned; we do not track
+			 * directories.
+			 */
+			continue;
+		}
+
+		/*
+		 * "rm" of a path that has changes need to be treated
+		 * carefully not to allow losing local changes
+		 * accidentally.  A local change could be (1) file in
+		 * work tree is different since the index; and/or (2)
+		 * the user staged a content that is different from
+		 * the current commit in the index.
+		 *
+		 * In such a case, you would need to --force the
+		 * removal.  However, "rm --cached" (remove only from
+		 * the index) is safe if the index matches the file in
+		 * the work tree or the HEAD commit, as it means that
+		 * the content being removed is available elsewhere.
+		 */
+
+		/*
+		 * Is the index different from the file in the work tree?
+		 */
+		if (ce_match_stat(ce, &st, 0))
+			local_changes = 1;
+
+		/*
+		 * Is the index different from the HEAD commit?  By
+		 * definition, before the very initial commit,
+		 * anything staged in the index is treated by the same
+		 * way as changed from the HEAD.
+		 */
+		if (no_head
+		     || get_tree_entry(head, name, sha1, &mode)
+		     || ce->ce_mode != create_ce_mode(mode)
+		     || hashcmp(ce->sha1, sha1))
+			staged_changes = 1;
+
+		/*
+		 * If the index does not match the file in the work
+		 * tree and if it does not match the HEAD commit
+		 * either, (1) "git rm" without --cached definitely
+		 * will lose information; (2) "git rm --cached" will
+		 * lose information unless it is about removing an
+		 * "intent to add" entry.
+		 */
+		if (local_changes && staged_changes) {
+			if (!index_only || !(ce->ce_flags & CE_INTENT_TO_ADD))
+				errs = error("'%s' has staged content different "
+					     "from both the file and the HEAD\n"
+					     "(use -f to force removal)", name);
+		}
+		else if (!index_only) {
+			if (staged_changes)
+				errs = error("'%s' has changes staged in the index\n"
+					     "(use --cached to keep the file, "
+					     "or -f to force removal)", name);
+			if (local_changes)
+				errs = error("'%s' has local modifications\n"
+					     "(use --cached to keep the file, "
+					     "or -f to force removal)", name);
+		}
+	}
+	return errs;
+}
+
+static struct lock_file lock_file;
+
+static int show_only = 0, force = 0, index_only = 0, recursive = 0, quiet = 0;
+static int ignore_unmatch = 0;
+
+static struct option builtin_rm_options[] = {
+	OPT__DRY_RUN(&show_only),
+	OPT__QUIET(&quiet),
+	OPT_BOOLEAN( 0 , "cached",         &index_only, "only remove from the index"),
+	OPT_BOOLEAN('f', "force",          &force,      "override the up-to-date check"),
+	OPT_BOOLEAN('r', NULL,             &recursive,  "allow recursive removal"),
+	OPT_BOOLEAN( 0 , "ignore-unmatch", &ignore_unmatch,
+				"exit with a zero status even if nothing matched"),
+	OPT_END(),
+};
+
+int cmd_rm(int argc, const char **argv, const char *prefix)
+{
+	int i, newfd;
+	const char **pathspec;
+	char *seen;
+
+	git_config(git_default_config, NULL);
+
+	argc = parse_options(argc, argv, prefix, builtin_rm_options,
+			     builtin_rm_usage, 0);
+	if (!argc)
+		usage_with_options(builtin_rm_usage, builtin_rm_options);
+
+	if (!index_only)
+		setup_work_tree();
+
+	newfd = hold_locked_index(&lock_file, 1);
+
+	if (read_cache() < 0)
+		die("index file corrupt");
+
+	pathspec = get_pathspec(prefix, argv);
+	refresh_index(&the_index, REFRESH_QUIET, pathspec, NULL, NULL);
+
+	seen = NULL;
+	for (i = 0; pathspec[i] ; i++)
+		/* nothing */;
+	seen = xcalloc(i, 1);
+
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (!match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen))
+			continue;
+		add_list(ce->name);
+	}
+
+	if (pathspec) {
+		const char *match;
+		int seen_any = 0;
+		for (i = 0; (match = pathspec[i]) != NULL ; i++) {
+			if (!seen[i]) {
+				if (!ignore_unmatch) {
+					die("pathspec '%s' did not match any files",
+					    match);
+				}
+			}
+			else {
+				seen_any = 1;
+			}
+			if (!recursive && seen[i] == MATCHED_RECURSIVELY)
+				die("not removing '%s' recursively without -r",
+				    *match ? match : ".");
+		}
+
+		if (! seen_any)
+			exit(0);
+	}
+
+	/*
+	 * If not forced, the file, the index and the HEAD (if exists)
+	 * must match; but the file can already been removed, since
+	 * this sequence is a natural "novice" way:
+	 *
+	 *	rm F; git rm F
+	 *
+	 * Further, if HEAD commit exists, "diff-index --cached" must
+	 * report no changes unless forced.
+	 */
+	if (!force) {
+		unsigned char sha1[20];
+		if (get_sha1("HEAD", sha1))
+			hashclr(sha1);
+		if (check_local_mod(sha1, index_only))
+			exit(1);
+	}
+
+	/*
+	 * First remove the names from the index: we won't commit
+	 * the index unless all of them succeed.
+	 */
+	for (i = 0; i < list.nr; i++) {
+		const char *path = list.name[i];
+		if (!quiet)
+			printf("rm '%s'\n", path);
+
+		if (remove_file_from_cache(path))
+			die("git rm: unable to remove %s", path);
+	}
+
+	if (show_only)
+		return 0;
+
+	/*
+	 * Then, unless we used "--cached", remove the filenames from
+	 * the workspace. If we fail to remove the first one, we
+	 * abort the "git rm" (but once we've successfully removed
+	 * any file at all, we'll go ahead and commit to it all:
+	 * by then we've already committed ourselves and can't fail
+	 * in the middle)
+	 */
+	if (!index_only) {
+		int removed = 0;
+		for (i = 0; i < list.nr; i++) {
+			const char *path = list.name[i];
+			if (!remove_path(path)) {
+				removed = 1;
+				continue;
+			}
+			if (!removed)
+				die_errno("git rm: '%s'", path);
+		}
+	}
+
+	if (active_cache_changed) {
+		if (write_cache(newfd, active_cache, active_nr) ||
+		    commit_locked_index(&lock_file))
+			die("Unable to write new index file");
+	}
+
+	return 0;
+}
diff --git a/builtin/send-pack.c b/builtin/send-pack.c
new file mode 100644
index 0000000..6019eac
--- /dev/null
+++ b/builtin/send-pack.c
@@ -0,0 +1,527 @@
+#include "cache.h"
+#include "commit.h"
+#include "refs.h"
+#include "pkt-line.h"
+#include "sideband.h"
+#include "run-command.h"
+#include "remote.h"
+#include "send-pack.h"
+#include "quote.h"
+#include "transport.h"
+
+static const char send_pack_usage[] =
+"git send-pack [--all | --mirror] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
+"  --all and explicit <ref> specification are mutually exclusive.";
+
+static struct send_pack_args args;
+
+static int feed_object(const unsigned char *sha1, int fd, int negative)
+{
+	char buf[42];
+
+	if (negative && !has_sha1_file(sha1))
+		return 1;
+
+	memcpy(buf + negative, sha1_to_hex(sha1), 40);
+	if (negative)
+		buf[0] = '^';
+	buf[40 + negative] = '\n';
+	return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
+}
+
+/*
+ * Make a pack stream and spit it out into file descriptor fd
+ */
+static int pack_objects(int fd, struct ref *refs, struct extra_have_objects *extra, struct send_pack_args *args)
+{
+	/*
+	 * The child becomes pack-objects --revs; we feed
+	 * the revision parameters to it via its stdin and
+	 * let its stdout go back to the other end.
+	 */
+	const char *argv[] = {
+		"pack-objects",
+		"--all-progress-implied",
+		"--revs",
+		"--stdout",
+		NULL,
+		NULL,
+		NULL,
+		NULL,
+	};
+	struct child_process po;
+	int i;
+
+	i = 4;
+	if (args->use_thin_pack)
+		argv[i++] = "--thin";
+	if (args->use_ofs_delta)
+		argv[i++] = "--delta-base-offset";
+	if (args->quiet)
+		argv[i++] = "-q";
+	memset(&po, 0, sizeof(po));
+	po.argv = argv;
+	po.in = -1;
+	po.out = args->stateless_rpc ? -1 : fd;
+	po.git_cmd = 1;
+	if (start_command(&po))
+		die_errno("git pack-objects failed");
+
+	/*
+	 * We feed the pack-objects we just spawned with revision
+	 * parameters by writing to the pipe.
+	 */
+	for (i = 0; i < extra->nr; i++)
+		if (!feed_object(extra->array[i], po.in, 1))
+			break;
+
+	while (refs) {
+		if (!is_null_sha1(refs->old_sha1) &&
+		    !feed_object(refs->old_sha1, po.in, 1))
+			break;
+		if (!is_null_sha1(refs->new_sha1) &&
+		    !feed_object(refs->new_sha1, po.in, 0))
+			break;
+		refs = refs->next;
+	}
+
+	close(po.in);
+
+	if (args->stateless_rpc) {
+		char *buf = xmalloc(LARGE_PACKET_MAX);
+		while (1) {
+			ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
+			if (n <= 0)
+				break;
+			send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
+		}
+		free(buf);
+		close(po.out);
+		po.out = -1;
+	}
+
+	if (finish_command(&po))
+		return error("pack-objects died with strange error");
+	return 0;
+}
+
+static int receive_status(int in, struct ref *refs)
+{
+	struct ref *hint;
+	char line[1000];
+	int ret = 0;
+	int len = packet_read_line(in, line, sizeof(line));
+	if (len < 10 || memcmp(line, "unpack ", 7))
+		return error("did not receive remote status");
+	if (memcmp(line, "unpack ok\n", 10)) {
+		char *p = line + strlen(line) - 1;
+		if (*p == '\n')
+			*p = '\0';
+		error("unpack failed: %s", line + 7);
+		ret = -1;
+	}
+	hint = NULL;
+	while (1) {
+		char *refname;
+		char *msg;
+		len = packet_read_line(in, line, sizeof(line));
+		if (!len)
+			break;
+		if (len < 3 ||
+		    (memcmp(line, "ok ", 3) && memcmp(line, "ng ", 3))) {
+			fprintf(stderr, "protocol error: %s\n", line);
+			ret = -1;
+			break;
+		}
+
+		line[strlen(line)-1] = '\0';
+		refname = line + 3;
+		msg = strchr(refname, ' ');
+		if (msg)
+			*msg++ = '\0';
+
+		/* first try searching at our hint, falling back to all refs */
+		if (hint)
+			hint = find_ref_by_name(hint, refname);
+		if (!hint)
+			hint = find_ref_by_name(refs, refname);
+		if (!hint) {
+			warning("remote reported status on unknown ref: %s",
+					refname);
+			continue;
+		}
+		if (hint->status != REF_STATUS_EXPECTING_REPORT) {
+			warning("remote reported status on unexpected ref: %s",
+					refname);
+			continue;
+		}
+
+		if (line[0] == 'o' && line[1] == 'k')
+			hint->status = REF_STATUS_OK;
+		else {
+			hint->status = REF_STATUS_REMOTE_REJECT;
+			ret = -1;
+		}
+		if (msg)
+			hint->remote_status = xstrdup(msg);
+		/* start our next search from the next ref */
+		hint = hint->next;
+	}
+	return ret;
+}
+
+static void print_helper_status(struct ref *ref)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	for (; ref; ref = ref->next) {
+		const char *msg = NULL;
+		const char *res;
+
+		switch(ref->status) {
+		case REF_STATUS_NONE:
+			res = "error";
+			msg = "no match";
+			break;
+
+		case REF_STATUS_OK:
+			res = "ok";
+			break;
+
+		case REF_STATUS_UPTODATE:
+			res = "ok";
+			msg = "up to date";
+			break;
+
+		case REF_STATUS_REJECT_NONFASTFORWARD:
+			res = "error";
+			msg = "non-fast forward";
+			break;
+
+		case REF_STATUS_REJECT_NODELETE:
+		case REF_STATUS_REMOTE_REJECT:
+			res = "error";
+			break;
+
+		case REF_STATUS_EXPECTING_REPORT:
+		default:
+			continue;
+		}
+
+		strbuf_reset(&buf);
+		strbuf_addf(&buf, "%s %s", res, ref->name);
+		if (ref->remote_status)
+			msg = ref->remote_status;
+		if (msg) {
+			strbuf_addch(&buf, ' ');
+			quote_two_c_style(&buf, "", msg, 0);
+		}
+		strbuf_addch(&buf, '\n');
+
+		safe_write(1, buf.buf, buf.len);
+	}
+	strbuf_release(&buf);
+}
+
+static int sideband_demux(int in, int out, void *data)
+{
+	int *fd = data;
+	int ret = recv_sideband("send-pack", fd[0], out);
+	close(out);
+	return ret;
+}
+
+int send_pack(struct send_pack_args *args,
+	      int fd[], struct child_process *conn,
+	      struct ref *remote_refs,
+	      struct extra_have_objects *extra_have)
+{
+	int in = fd[0];
+	int out = fd[1];
+	struct strbuf req_buf = STRBUF_INIT;
+	struct ref *ref;
+	int new_refs;
+	int allow_deleting_refs = 0;
+	int status_report = 0;
+	int use_sideband = 0;
+	unsigned cmds_sent = 0;
+	int ret;
+	struct async demux;
+
+	/* Does the other end support the reporting? */
+	if (server_supports("report-status"))
+		status_report = 1;
+	if (server_supports("delete-refs"))
+		allow_deleting_refs = 1;
+	if (server_supports("ofs-delta"))
+		args->use_ofs_delta = 1;
+	if (server_supports("side-band-64k"))
+		use_sideband = 1;
+
+	if (!remote_refs) {
+		fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
+			"Perhaps you should specify a branch such as 'master'.\n");
+		return 0;
+	}
+
+	/*
+	 * Finally, tell the other end!
+	 */
+	new_refs = 0;
+	for (ref = remote_refs; ref; ref = ref->next) {
+		if (!ref->peer_ref && !args->send_mirror)
+			continue;
+
+		/* Check for statuses set by set_ref_status_for_push() */
+		switch (ref->status) {
+		case REF_STATUS_REJECT_NONFASTFORWARD:
+		case REF_STATUS_UPTODATE:
+			continue;
+		default:
+			; /* do nothing */
+		}
+
+		if (ref->deletion && !allow_deleting_refs) {
+			ref->status = REF_STATUS_REJECT_NODELETE;
+			continue;
+		}
+
+		if (!ref->deletion)
+			new_refs++;
+
+		if (args->dry_run) {
+			ref->status = REF_STATUS_OK;
+		} else {
+			char *old_hex = sha1_to_hex(ref->old_sha1);
+			char *new_hex = sha1_to_hex(ref->new_sha1);
+
+			if (!cmds_sent && (status_report || use_sideband)) {
+				packet_buf_write(&req_buf, "%s %s %s%c%s%s",
+					old_hex, new_hex, ref->name, 0,
+					status_report ? " report-status" : "",
+					use_sideband ? " side-band-64k" : "");
+			}
+			else
+				packet_buf_write(&req_buf, "%s %s %s",
+					old_hex, new_hex, ref->name);
+			ref->status = status_report ?
+				REF_STATUS_EXPECTING_REPORT :
+				REF_STATUS_OK;
+			cmds_sent++;
+		}
+	}
+
+	if (args->stateless_rpc) {
+		if (!args->dry_run && cmds_sent) {
+			packet_buf_flush(&req_buf);
+			send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
+		}
+	} else {
+		safe_write(out, req_buf.buf, req_buf.len);
+		packet_flush(out);
+	}
+	strbuf_release(&req_buf);
+
+	if (use_sideband && cmds_sent) {
+		memset(&demux, 0, sizeof(demux));
+		demux.proc = sideband_demux;
+		demux.data = fd;
+		demux.out = -1;
+		if (start_async(&demux))
+			die("receive-pack: unable to fork off sideband demultiplexer");
+		in = demux.out;
+	}
+
+	if (new_refs && cmds_sent) {
+		if (pack_objects(out, remote_refs, extra_have, args) < 0) {
+			for (ref = remote_refs; ref; ref = ref->next)
+				ref->status = REF_STATUS_NONE;
+			if (use_sideband)
+				finish_async(&demux);
+			return -1;
+		}
+	}
+	if (args->stateless_rpc && cmds_sent)
+		packet_flush(out);
+
+	if (status_report && cmds_sent)
+		ret = receive_status(in, remote_refs);
+	else
+		ret = 0;
+	if (args->stateless_rpc)
+		packet_flush(out);
+
+	if (use_sideband && cmds_sent) {
+		if (finish_async(&demux)) {
+			error("error in sideband demultiplexer");
+			ret = -1;
+		}
+		close(demux.out);
+	}
+
+	if (ret < 0)
+		return ret;
+	for (ref = remote_refs; ref; ref = ref->next) {
+		switch (ref->status) {
+		case REF_STATUS_NONE:
+		case REF_STATUS_UPTODATE:
+		case REF_STATUS_OK:
+			break;
+		default:
+			return -1;
+		}
+	}
+	return 0;
+}
+
+int cmd_send_pack(int argc, const char **argv, const char *prefix)
+{
+	int i, nr_refspecs = 0;
+	const char **refspecs = NULL;
+	const char *remote_name = NULL;
+	struct remote *remote = NULL;
+	const char *dest = NULL;
+	int fd[2];
+	struct child_process *conn;
+	struct extra_have_objects extra_have;
+	struct ref *remote_refs, *local_refs;
+	int ret;
+	int helper_status = 0;
+	int send_all = 0;
+	const char *receivepack = "git-receive-pack";
+	int flags;
+	int nonfastforward = 0;
+
+	argv++;
+	for (i = 1; i < argc; i++, argv++) {
+		const char *arg = *argv;
+
+		if (*arg == '-') {
+			if (!prefixcmp(arg, "--receive-pack=")) {
+				receivepack = arg + 15;
+				continue;
+			}
+			if (!prefixcmp(arg, "--exec=")) {
+				receivepack = arg + 7;
+				continue;
+			}
+			if (!prefixcmp(arg, "--remote=")) {
+				remote_name = arg + 9;
+				continue;
+			}
+			if (!strcmp(arg, "--all")) {
+				send_all = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--dry-run")) {
+				args.dry_run = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--mirror")) {
+				args.send_mirror = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--force")) {
+				args.force_update = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--verbose")) {
+				args.verbose = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--thin")) {
+				args.use_thin_pack = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--stateless-rpc")) {
+				args.stateless_rpc = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--helper-status")) {
+				helper_status = 1;
+				continue;
+			}
+			usage(send_pack_usage);
+		}
+		if (!dest) {
+			dest = arg;
+			continue;
+		}
+		refspecs = (const char **) argv;
+		nr_refspecs = argc - i;
+		break;
+	}
+	if (!dest)
+		usage(send_pack_usage);
+	/*
+	 * --all and --mirror are incompatible; neither makes sense
+	 * with any refspecs.
+	 */
+	if ((refspecs && (send_all || args.send_mirror)) ||
+	    (send_all && args.send_mirror))
+		usage(send_pack_usage);
+
+	if (remote_name) {
+		remote = remote_get(remote_name);
+		if (!remote_has_url(remote, dest)) {
+			die("Destination %s is not a uri for %s",
+			    dest, remote_name);
+		}
+	}
+
+	if (args.stateless_rpc) {
+		conn = NULL;
+		fd[0] = 0;
+		fd[1] = 1;
+	} else {
+		conn = git_connect(fd, dest, receivepack,
+			args.verbose ? CONNECT_VERBOSE : 0);
+	}
+
+	memset(&extra_have, 0, sizeof(extra_have));
+
+	get_remote_heads(fd[0], &remote_refs, 0, NULL, REF_NORMAL,
+			 &extra_have);
+
+	transport_verify_remote_names(nr_refspecs, refspecs);
+
+	local_refs = get_local_heads();
+
+	flags = MATCH_REFS_NONE;
+
+	if (send_all)
+		flags |= MATCH_REFS_ALL;
+	if (args.send_mirror)
+		flags |= MATCH_REFS_MIRROR;
+
+	/* match them up */
+	if (match_refs(local_refs, &remote_refs, nr_refspecs, refspecs, flags))
+		return -1;
+
+	set_ref_status_for_push(remote_refs, args.send_mirror,
+		args.force_update);
+
+	ret = send_pack(&args, fd, conn, remote_refs, &extra_have);
+
+	if (helper_status)
+		print_helper_status(remote_refs);
+
+	close(fd[1]);
+	close(fd[0]);
+
+	ret |= finish_connect(conn);
+
+	if (!helper_status)
+		transport_print_push_status(dest, remote_refs, args.verbose, 0, &nonfastforward);
+
+	if (!args.dry_run && remote) {
+		struct ref *ref;
+		for (ref = remote_refs; ref; ref = ref->next)
+			transport_update_tracking_ref(remote, ref, args.verbose);
+	}
+
+	if (!ret && !transport_refs_pushed(remote_refs))
+		fprintf(stderr, "Everything up-to-date\n");
+
+	return ret;
+}
diff --git a/builtin/shortlog.c b/builtin/shortlog.c
new file mode 100644
index 0000000..06320f5
--- /dev/null
+++ b/builtin/shortlog.c
@@ -0,0 +1,356 @@
+#include "builtin.h"
+#include "cache.h"
+#include "commit.h"
+#include "diff.h"
+#include "string-list.h"
+#include "revision.h"
+#include "utf8.h"
+#include "mailmap.h"
+#include "shortlog.h"
+#include "parse-options.h"
+
+static char const * const shortlog_usage[] = {
+	"git shortlog [-n] [-s] [-e] [-w] [rev-opts] [--] [<commit-id>... ]",
+	"",
+	"[rev-opts] are documented in git-rev-list(1)",
+	NULL
+};
+
+static int compare_by_number(const void *a1, const void *a2)
+{
+	const struct string_list_item *i1 = a1, *i2 = a2;
+	const struct string_list *l1 = i1->util, *l2 = i2->util;
+
+	if (l1->nr < l2->nr)
+		return 1;
+	else if (l1->nr == l2->nr)
+		return 0;
+	else
+		return -1;
+}
+
+const char *format_subject(struct strbuf *sb, const char *msg,
+			   const char *line_separator);
+
+static void insert_one_record(struct shortlog *log,
+			      const char *author,
+			      const char *oneline)
+{
+	const char *dot3 = log->common_repo_prefix;
+	char *buffer, *p;
+	struct string_list_item *item;
+	char namebuf[1024];
+	char emailbuf[1024];
+	size_t len;
+	const char *eol;
+	const char *boemail, *eoemail;
+	struct strbuf subject = STRBUF_INIT;
+
+	boemail = strchr(author, '<');
+	if (!boemail)
+		return;
+	eoemail = strchr(boemail, '>');
+	if (!eoemail)
+		return;
+
+	/* copy author name to namebuf, to support matching on both name and email */
+	memcpy(namebuf, author, boemail - author);
+	len = boemail - author;
+	while (len > 0 && isspace(namebuf[len-1]))
+		len--;
+	namebuf[len] = 0;
+
+	/* copy email name to emailbuf, to allow email replacement as well */
+	memcpy(emailbuf, boemail+1, eoemail - boemail);
+	emailbuf[eoemail - boemail - 1] = 0;
+
+	if (!map_user(&log->mailmap, emailbuf, sizeof(emailbuf), namebuf, sizeof(namebuf))) {
+		while (author < boemail && isspace(*author))
+			author++;
+		for (len = 0;
+		     len < sizeof(namebuf) - 1 && author + len < boemail;
+		     len++)
+			namebuf[len] = author[len];
+		while (0 < len && isspace(namebuf[len-1]))
+			len--;
+		namebuf[len] = '\0';
+	}
+	else
+		len = strlen(namebuf);
+
+	if (log->email) {
+		size_t room = sizeof(namebuf) - len - 1;
+		int maillen = strlen(emailbuf);
+		snprintf(namebuf + len, room, " <%.*s>", maillen, emailbuf);
+	}
+
+	item = string_list_insert(namebuf, &log->list);
+	if (item->util == NULL)
+		item->util = xcalloc(1, sizeof(struct string_list));
+
+	/* Skip any leading whitespace, including any blank lines. */
+	while (*oneline && isspace(*oneline))
+		oneline++;
+	eol = strchr(oneline, '\n');
+	if (!eol)
+		eol = oneline + strlen(oneline);
+	if (!prefixcmp(oneline, "[PATCH")) {
+		char *eob = strchr(oneline, ']');
+		if (eob && (!eol || eob < eol))
+			oneline = eob + 1;
+	}
+	while (*oneline && isspace(*oneline) && *oneline != '\n')
+		oneline++;
+	format_subject(&subject, oneline, " ");
+	buffer = strbuf_detach(&subject, NULL);
+
+	if (dot3) {
+		int dot3len = strlen(dot3);
+		if (dot3len > 5) {
+			while ((p = strstr(buffer, dot3)) != NULL) {
+				int taillen = strlen(p) - dot3len;
+				memcpy(p, "/.../", 5);
+				memmove(p + 5, p + dot3len, taillen + 1);
+			}
+		}
+	}
+
+	string_list_append(buffer, item->util);
+}
+
+static void read_from_stdin(struct shortlog *log)
+{
+	char author[1024], oneline[1024];
+
+	while (fgets(author, sizeof(author), stdin) != NULL) {
+		if (!(author[0] == 'A' || author[0] == 'a') ||
+		    prefixcmp(author + 1, "uthor: "))
+			continue;
+		while (fgets(oneline, sizeof(oneline), stdin) &&
+		       oneline[0] != '\n')
+			; /* discard headers */
+		while (fgets(oneline, sizeof(oneline), stdin) &&
+		       oneline[0] == '\n')
+			; /* discard blanks */
+		insert_one_record(log, author + 8, oneline);
+	}
+}
+
+void shortlog_add_commit(struct shortlog *log, struct commit *commit)
+{
+	const char *author = NULL, *buffer;
+	struct strbuf buf = STRBUF_INIT;
+	struct strbuf ufbuf = STRBUF_INIT;
+	struct pretty_print_context ctx = {0};
+
+	pretty_print_commit(CMIT_FMT_RAW, commit, &buf, &ctx);
+	buffer = buf.buf;
+	while (*buffer && *buffer != '\n') {
+		const char *eol = strchr(buffer, '\n');
+
+		if (eol == NULL)
+			eol = buffer + strlen(buffer);
+		else
+			eol++;
+
+		if (!prefixcmp(buffer, "author "))
+			author = buffer + 7;
+		buffer = eol;
+	}
+	if (!author)
+		die("Missing author: %s",
+		    sha1_to_hex(commit->object.sha1));
+	if (log->user_format) {
+		struct pretty_print_context ctx = {0};
+		ctx.abbrev = DEFAULT_ABBREV;
+		ctx.subject = "";
+		ctx.after_subject = "";
+		ctx.date_mode = DATE_NORMAL;
+		pretty_print_commit(CMIT_FMT_USERFORMAT, commit, &ufbuf, &ctx);
+		buffer = ufbuf.buf;
+	} else if (*buffer) {
+		buffer++;
+	}
+	insert_one_record(log, author, !*buffer ? "<none>" : buffer);
+	strbuf_release(&ufbuf);
+	strbuf_release(&buf);
+}
+
+static void get_from_rev(struct rev_info *rev, struct shortlog *log)
+{
+	struct commit *commit;
+
+	if (prepare_revision_walk(rev))
+		die("revision walk setup failed");
+	while ((commit = get_revision(rev)) != NULL)
+		shortlog_add_commit(log, commit);
+}
+
+static int parse_uint(char const **arg, int comma, int defval)
+{
+	unsigned long ul;
+	int ret;
+	char *endp;
+
+	ul = strtoul(*arg, &endp, 10);
+	if (*endp && *endp != comma)
+		return -1;
+	if (ul > INT_MAX)
+		return -1;
+	ret = *arg == endp ? defval : (int)ul;
+	*arg = *endp ? endp + 1 : endp;
+	return ret;
+}
+
+static const char wrap_arg_usage[] = "-w[<width>[,<indent1>[,<indent2>]]]";
+#define DEFAULT_WRAPLEN 76
+#define DEFAULT_INDENT1 6
+#define DEFAULT_INDENT2 9
+
+static int parse_wrap_args(const struct option *opt, const char *arg, int unset)
+{
+	struct shortlog *log = opt->value;
+
+	log->wrap_lines = !unset;
+	if (unset)
+		return 0;
+	if (!arg) {
+		log->wrap = DEFAULT_WRAPLEN;
+		log->in1 = DEFAULT_INDENT1;
+		log->in2 = DEFAULT_INDENT2;
+		return 0;
+	}
+
+	log->wrap = parse_uint(&arg, ',', DEFAULT_WRAPLEN);
+	log->in1 = parse_uint(&arg, ',', DEFAULT_INDENT1);
+	log->in2 = parse_uint(&arg, '\0', DEFAULT_INDENT2);
+	if (log->wrap < 0 || log->in1 < 0 || log->in2 < 0)
+		return error(wrap_arg_usage);
+	if (log->wrap &&
+	    ((log->in1 && log->wrap <= log->in1) ||
+	     (log->in2 && log->wrap <= log->in2)))
+		return error(wrap_arg_usage);
+	return 0;
+}
+
+void shortlog_init(struct shortlog *log)
+{
+	memset(log, 0, sizeof(*log));
+
+	read_mailmap(&log->mailmap, &log->common_repo_prefix);
+
+	log->list.strdup_strings = 1;
+	log->wrap = DEFAULT_WRAPLEN;
+	log->in1 = DEFAULT_INDENT1;
+	log->in2 = DEFAULT_INDENT2;
+}
+
+int cmd_shortlog(int argc, const char **argv, const char *prefix)
+{
+	static struct shortlog log;
+	static struct rev_info rev;
+	int nongit;
+
+	static const struct option options[] = {
+		OPT_BOOLEAN('n', "numbered", &log.sort_by_number,
+			    "sort output according to the number of commits per author"),
+		OPT_BOOLEAN('s', "summary", &log.summary,
+			    "Suppress commit descriptions, only provides commit count"),
+		OPT_BOOLEAN('e', "email", &log.email,
+			    "Show the email address of each author"),
+		{ OPTION_CALLBACK, 'w', NULL, &log, "w[,i1[,i2]]",
+			"Linewrap output", PARSE_OPT_OPTARG, &parse_wrap_args },
+		OPT_END(),
+	};
+
+	struct parse_opt_ctx_t ctx;
+
+	prefix = setup_git_directory_gently(&nongit);
+	git_config(git_default_config, NULL);
+	shortlog_init(&log);
+	init_revisions(&rev, prefix);
+	parse_options_start(&ctx, argc, argv, prefix, PARSE_OPT_KEEP_DASHDASH |
+			    PARSE_OPT_KEEP_ARGV0);
+
+	for (;;) {
+		switch (parse_options_step(&ctx, options, shortlog_usage)) {
+		case PARSE_OPT_HELP:
+			exit(129);
+		case PARSE_OPT_DONE:
+			goto parse_done;
+		}
+		parse_revision_opt(&rev, &ctx, options, shortlog_usage);
+	}
+parse_done:
+	argc = parse_options_end(&ctx);
+
+	if (setup_revisions(argc, argv, &rev, NULL) != 1) {
+		error("unrecognized argument: %s", argv[1]);
+		usage_with_options(shortlog_usage, options);
+	}
+
+	log.user_format = rev.commit_format == CMIT_FMT_USERFORMAT;
+
+	/* assume HEAD if from a tty */
+	if (!nongit && !rev.pending.nr && isatty(0))
+		add_head_to_pending(&rev);
+	if (rev.pending.nr == 0) {
+		if (isatty(0))
+			fprintf(stderr, "(reading log message from standard input)\n");
+		read_from_stdin(&log);
+	}
+	else
+		get_from_rev(&rev, &log);
+
+	shortlog_output(&log);
+	return 0;
+}
+
+static void add_wrapped_shortlog_msg(struct strbuf *sb, const char *s,
+				     const struct shortlog *log)
+{
+	int col = strbuf_add_wrapped_text(sb, s, log->in1, log->in2, log->wrap);
+	if (col != log->wrap)
+		strbuf_addch(sb, '\n');
+}
+
+void shortlog_output(struct shortlog *log)
+{
+	int i, j;
+	struct strbuf sb = STRBUF_INIT;
+
+	if (log->sort_by_number)
+		qsort(log->list.items, log->list.nr, sizeof(struct string_list_item),
+			compare_by_number);
+	for (i = 0; i < log->list.nr; i++) {
+		struct string_list *onelines = log->list.items[i].util;
+
+		if (log->summary) {
+			printf("%6d\t%s\n", onelines->nr, log->list.items[i].string);
+		} else {
+			printf("%s (%d):\n", log->list.items[i].string, onelines->nr);
+			for (j = onelines->nr - 1; j >= 0; j--) {
+				const char *msg = onelines->items[j].string;
+
+				if (log->wrap_lines) {
+					strbuf_reset(&sb);
+					add_wrapped_shortlog_msg(&sb, msg, log);
+					fwrite(sb.buf, sb.len, 1, stdout);
+				}
+				else
+					printf("      %s\n", msg);
+			}
+			putchar('\n');
+		}
+
+		onelines->strdup_strings = 1;
+		string_list_clear(onelines, 0);
+		free(onelines);
+		log->list.items[i].util = NULL;
+	}
+
+	strbuf_release(&sb);
+	log->list.strdup_strings = 1;
+	string_list_clear(&log->list, 1);
+	clear_mailmap(&log->mailmap);
+}
diff --git a/builtin/show-branch.c b/builtin/show-branch.c
new file mode 100644
index 0000000..e20fcf3
--- /dev/null
+++ b/builtin/show-branch.c
@@ -0,0 +1,967 @@
+#include "cache.h"
+#include "commit.h"
+#include "refs.h"
+#include "builtin.h"
+#include "color.h"
+#include "parse-options.h"
+
+static const char* show_branch_usage[] = {
+    "git show-branch [-a|--all] [-r|--remotes] [--topo-order | --date-order] [--current] [--color[=<when>] | --no-color] [--sparse] [--more=<n> | --list | --independent | --merge-base] [--no-name | --sha1-name] [--topics] [<rev> | <glob>]...",
+    "git show-branch (-g|--reflog)[=<n>[,<base>]] [--list] [<ref>]",
+    NULL
+};
+
+static int showbranch_use_color = -1;
+static char column_colors[][COLOR_MAXLEN] = {
+	GIT_COLOR_RED,
+	GIT_COLOR_GREEN,
+	GIT_COLOR_YELLOW,
+	GIT_COLOR_BLUE,
+	GIT_COLOR_MAGENTA,
+	GIT_COLOR_CYAN,
+};
+
+#define COLUMN_COLORS_MAX (ARRAY_SIZE(column_colors))
+
+static int default_num;
+static int default_alloc;
+static const char **default_arg;
+
+#define UNINTERESTING	01
+
+#define REV_SHIFT	 2
+#define MAX_REVS	(FLAG_BITS - REV_SHIFT) /* should not exceed bits_per_int - REV_SHIFT */
+
+#define DEFAULT_REFLOG	4
+
+static const char *get_color_code(int idx)
+{
+	if (showbranch_use_color)
+		return column_colors[idx];
+	return "";
+}
+
+static const char *get_color_reset_code(void)
+{
+	if (showbranch_use_color)
+		return GIT_COLOR_RESET;
+	return "";
+}
+
+static struct commit *interesting(struct commit_list *list)
+{
+	while (list) {
+		struct commit *commit = list->item;
+		list = list->next;
+		if (commit->object.flags & UNINTERESTING)
+			continue;
+		return commit;
+	}
+	return NULL;
+}
+
+static struct commit *pop_one_commit(struct commit_list **list_p)
+{
+	struct commit *commit;
+	struct commit_list *list;
+	list = *list_p;
+	commit = list->item;
+	*list_p = list->next;
+	free(list);
+	return commit;
+}
+
+struct commit_name {
+	const char *head_name; /* which head's ancestor? */
+	int generation; /* how many parents away from head_name */
+};
+
+/* Name the commit as nth generation ancestor of head_name;
+ * we count only the first-parent relationship for naming purposes.
+ */
+static void name_commit(struct commit *commit, const char *head_name, int nth)
+{
+	struct commit_name *name;
+	if (!commit->util)
+		commit->util = xmalloc(sizeof(struct commit_name));
+	name = commit->util;
+	name->head_name = head_name;
+	name->generation = nth;
+}
+
+/* Parent is the first parent of the commit.  We may name it
+ * as (n+1)th generation ancestor of the same head_name as
+ * commit is nth generation ancestor of, if that generation
+ * number is better than the name it already has.
+ */
+static void name_parent(struct commit *commit, struct commit *parent)
+{
+	struct commit_name *commit_name = commit->util;
+	struct commit_name *parent_name = parent->util;
+	if (!commit_name)
+		return;
+	if (!parent_name ||
+	    commit_name->generation + 1 < parent_name->generation)
+		name_commit(parent, commit_name->head_name,
+			    commit_name->generation + 1);
+}
+
+static int name_first_parent_chain(struct commit *c)
+{
+	int i = 0;
+	while (c) {
+		struct commit *p;
+		if (!c->util)
+			break;
+		if (!c->parents)
+			break;
+		p = c->parents->item;
+		if (!p->util) {
+			name_parent(c, p);
+			i++;
+		}
+		else
+			break;
+		c = p;
+	}
+	return i;
+}
+
+static void name_commits(struct commit_list *list,
+			 struct commit **rev,
+			 char **ref_name,
+			 int num_rev)
+{
+	struct commit_list *cl;
+	struct commit *c;
+	int i;
+
+	/* First give names to the given heads */
+	for (cl = list; cl; cl = cl->next) {
+		c = cl->item;
+		if (c->util)
+			continue;
+		for (i = 0; i < num_rev; i++) {
+			if (rev[i] == c) {
+				name_commit(c, ref_name[i], 0);
+				break;
+			}
+		}
+	}
+
+	/* Then commits on the first parent ancestry chain */
+	do {
+		i = 0;
+		for (cl = list; cl; cl = cl->next) {
+			i += name_first_parent_chain(cl->item);
+		}
+	} while (i);
+
+	/* Finally, any unnamed commits */
+	do {
+		i = 0;
+		for (cl = list; cl; cl = cl->next) {
+			struct commit_list *parents;
+			struct commit_name *n;
+			int nth;
+			c = cl->item;
+			if (!c->util)
+				continue;
+			n = c->util;
+			parents = c->parents;
+			nth = 0;
+			while (parents) {
+				struct commit *p = parents->item;
+				char newname[1000], *en;
+				parents = parents->next;
+				nth++;
+				if (p->util)
+					continue;
+				en = newname;
+				switch (n->generation) {
+				case 0:
+					en += sprintf(en, "%s", n->head_name);
+					break;
+				case 1:
+					en += sprintf(en, "%s^", n->head_name);
+					break;
+				default:
+					en += sprintf(en, "%s~%d",
+						n->head_name, n->generation);
+					break;
+				}
+				if (nth == 1)
+					en += sprintf(en, "^");
+				else
+					en += sprintf(en, "^%d", nth);
+				name_commit(p, xstrdup(newname), 0);
+				i++;
+				name_first_parent_chain(p);
+			}
+		}
+	} while (i);
+}
+
+static int mark_seen(struct commit *commit, struct commit_list **seen_p)
+{
+	if (!commit->object.flags) {
+		commit_list_insert(commit, seen_p);
+		return 1;
+	}
+	return 0;
+}
+
+static void join_revs(struct commit_list **list_p,
+		      struct commit_list **seen_p,
+		      int num_rev, int extra)
+{
+	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
+	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
+
+	while (*list_p) {
+		struct commit_list *parents;
+		int still_interesting = !!interesting(*list_p);
+		struct commit *commit = pop_one_commit(list_p);
+		int flags = commit->object.flags & all_mask;
+
+		if (!still_interesting && extra <= 0)
+			break;
+
+		mark_seen(commit, seen_p);
+		if ((flags & all_revs) == all_revs)
+			flags |= UNINTERESTING;
+		parents = commit->parents;
+
+		while (parents) {
+			struct commit *p = parents->item;
+			int this_flag = p->object.flags;
+			parents = parents->next;
+			if ((this_flag & flags) == flags)
+				continue;
+			if (!p->object.parsed)
+				parse_commit(p);
+			if (mark_seen(p, seen_p) && !still_interesting)
+				extra--;
+			p->object.flags |= flags;
+			insert_by_date(p, list_p);
+		}
+	}
+
+	/*
+	 * Postprocess to complete well-poisoning.
+	 *
+	 * At this point we have all the commits we have seen in
+	 * seen_p list.  Mark anything that can be reached from
+	 * uninteresting commits not interesting.
+	 */
+	for (;;) {
+		int changed = 0;
+		struct commit_list *s;
+		for (s = *seen_p; s; s = s->next) {
+			struct commit *c = s->item;
+			struct commit_list *parents;
+
+			if (((c->object.flags & all_revs) != all_revs) &&
+			    !(c->object.flags & UNINTERESTING))
+				continue;
+
+			/* The current commit is either a merge base or
+			 * already uninteresting one.  Mark its parents
+			 * as uninteresting commits _only_ if they are
+			 * already parsed.  No reason to find new ones
+			 * here.
+			 */
+			parents = c->parents;
+			while (parents) {
+				struct commit *p = parents->item;
+				parents = parents->next;
+				if (!(p->object.flags & UNINTERESTING)) {
+					p->object.flags |= UNINTERESTING;
+					changed = 1;
+				}
+			}
+		}
+		if (!changed)
+			break;
+	}
+}
+
+static void show_one_commit(struct commit *commit, int no_name)
+{
+	struct strbuf pretty = STRBUF_INIT;
+	const char *pretty_str = "(unavailable)";
+	struct commit_name *name = commit->util;
+
+	if (commit->object.parsed) {
+		struct pretty_print_context ctx = {0};
+		pretty_print_commit(CMIT_FMT_ONELINE, commit, &pretty, &ctx);
+		pretty_str = pretty.buf;
+	}
+	if (!prefixcmp(pretty_str, "[PATCH] "))
+		pretty_str += 8;
+
+	if (!no_name) {
+		if (name && name->head_name) {
+			printf("[%s", name->head_name);
+			if (name->generation) {
+				if (name->generation == 1)
+					printf("^");
+				else
+					printf("~%d", name->generation);
+			}
+			printf("] ");
+		}
+		else
+			printf("[%s] ",
+			       find_unique_abbrev(commit->object.sha1, 7));
+	}
+	puts(pretty_str);
+	strbuf_release(&pretty);
+}
+
+static char *ref_name[MAX_REVS + 1];
+static int ref_name_cnt;
+
+static const char *find_digit_prefix(const char *s, int *v)
+{
+	const char *p;
+	int ver;
+	char ch;
+
+	for (p = s, ver = 0;
+	     '0' <= (ch = *p) && ch <= '9';
+	     p++)
+		ver = ver * 10 + ch - '0';
+	*v = ver;
+	return p;
+}
+
+
+static int version_cmp(const char *a, const char *b)
+{
+	while (1) {
+		int va, vb;
+
+		a = find_digit_prefix(a, &va);
+		b = find_digit_prefix(b, &vb);
+		if (va != vb)
+			return va - vb;
+
+		while (1) {
+			int ca = *a;
+			int cb = *b;
+			if ('0' <= ca && ca <= '9')
+				ca = 0;
+			if ('0' <= cb && cb <= '9')
+				cb = 0;
+			if (ca != cb)
+				return ca - cb;
+			if (!ca)
+				break;
+			a++;
+			b++;
+		}
+		if (!*a && !*b)
+			return 0;
+	}
+}
+
+static int compare_ref_name(const void *a_, const void *b_)
+{
+	const char * const*a = a_, * const*b = b_;
+	return version_cmp(*a, *b);
+}
+
+static void sort_ref_range(int bottom, int top)
+{
+	qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
+	      compare_ref_name);
+}
+
+static int append_ref(const char *refname, const unsigned char *sha1,
+		      int allow_dups)
+{
+	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+	int i;
+
+	if (!commit)
+		return 0;
+
+	if (!allow_dups) {
+		/* Avoid adding the same thing twice */
+		for (i = 0; i < ref_name_cnt; i++)
+			if (!strcmp(refname, ref_name[i]))
+				return 0;
+	}
+	if (MAX_REVS <= ref_name_cnt) {
+		warning("ignoring %s; cannot handle more than %d refs",
+			refname, MAX_REVS);
+		return 0;
+	}
+	ref_name[ref_name_cnt++] = xstrdup(refname);
+	ref_name[ref_name_cnt] = NULL;
+	return 0;
+}
+
+static int append_head_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	unsigned char tmp[20];
+	int ofs = 11;
+	if (prefixcmp(refname, "refs/heads/"))
+		return 0;
+	/* If both heads/foo and tags/foo exists, get_sha1 would
+	 * get confused.
+	 */
+	if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
+		ofs = 5;
+	return append_ref(refname + ofs, sha1, 0);
+}
+
+static int append_remote_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	unsigned char tmp[20];
+	int ofs = 13;
+	if (prefixcmp(refname, "refs/remotes/"))
+		return 0;
+	/* If both heads/foo and tags/foo exists, get_sha1 would
+	 * get confused.
+	 */
+	if (get_sha1(refname + ofs, tmp) || hashcmp(tmp, sha1))
+		ofs = 5;
+	return append_ref(refname + ofs, sha1, 0);
+}
+
+static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	if (prefixcmp(refname, "refs/tags/"))
+		return 0;
+	return append_ref(refname + 5, sha1, 0);
+}
+
+static const char *match_ref_pattern = NULL;
+static int match_ref_slash = 0;
+static int count_slash(const char *s)
+{
+	int cnt = 0;
+	while (*s)
+		if (*s++ == '/')
+			cnt++;
+	return cnt;
+}
+
+static int append_matching_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	/* we want to allow pattern hold/<asterisk> to show all
+	 * branches under refs/heads/hold/, and v0.99.9? to show
+	 * refs/tags/v0.99.9a and friends.
+	 */
+	const char *tail;
+	int slash = count_slash(refname);
+	for (tail = refname; *tail && match_ref_slash < slash; )
+		if (*tail++ == '/')
+			slash--;
+	if (!*tail)
+		return 0;
+	if (fnmatch(match_ref_pattern, tail, 0))
+		return 0;
+	if (!prefixcmp(refname, "refs/heads/"))
+		return append_head_ref(refname, sha1, flag, cb_data);
+	if (!prefixcmp(refname, "refs/tags/"))
+		return append_tag_ref(refname, sha1, flag, cb_data);
+	return append_ref(refname, sha1, 0);
+}
+
+static void snarf_refs(int head, int remotes)
+{
+	if (head) {
+		int orig_cnt = ref_name_cnt;
+		for_each_ref(append_head_ref, NULL);
+		sort_ref_range(orig_cnt, ref_name_cnt);
+	}
+	if (remotes) {
+		int orig_cnt = ref_name_cnt;
+		for_each_ref(append_remote_ref, NULL);
+		sort_ref_range(orig_cnt, ref_name_cnt);
+	}
+}
+
+static int rev_is_head(char *head, int headlen, char *name,
+		       unsigned char *head_sha1, unsigned char *sha1)
+{
+	if ((!head[0]) ||
+	    (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
+		return 0;
+	if (!prefixcmp(head, "refs/heads/"))
+		head += 11;
+	if (!prefixcmp(name, "refs/heads/"))
+		name += 11;
+	else if (!prefixcmp(name, "heads/"))
+		name += 6;
+	return !strcmp(head, name);
+}
+
+static int show_merge_base(struct commit_list *seen, int num_rev)
+{
+	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
+	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
+	int exit_status = 1;
+
+	while (seen) {
+		struct commit *commit = pop_one_commit(&seen);
+		int flags = commit->object.flags & all_mask;
+		if (!(flags & UNINTERESTING) &&
+		    ((flags & all_revs) == all_revs)) {
+			puts(sha1_to_hex(commit->object.sha1));
+			exit_status = 0;
+			commit->object.flags |= UNINTERESTING;
+		}
+	}
+	return exit_status;
+}
+
+static int show_independent(struct commit **rev,
+			    int num_rev,
+			    char **ref_name,
+			    unsigned int *rev_mask)
+{
+	int i;
+
+	for (i = 0; i < num_rev; i++) {
+		struct commit *commit = rev[i];
+		unsigned int flag = rev_mask[i];
+
+		if (commit->object.flags == flag)
+			puts(sha1_to_hex(commit->object.sha1));
+		commit->object.flags |= UNINTERESTING;
+	}
+	return 0;
+}
+
+static void append_one_rev(const char *av)
+{
+	unsigned char revkey[20];
+	if (!get_sha1(av, revkey)) {
+		append_ref(av, revkey, 0);
+		return;
+	}
+	if (strchr(av, '*') || strchr(av, '?') || strchr(av, '[')) {
+		/* glob style match */
+		int saved_matches = ref_name_cnt;
+		match_ref_pattern = av;
+		match_ref_slash = count_slash(av);
+		for_each_ref(append_matching_ref, NULL);
+		if (saved_matches == ref_name_cnt &&
+		    ref_name_cnt < MAX_REVS)
+			error("no matching refs with %s", av);
+		if (saved_matches + 1 < ref_name_cnt)
+			sort_ref_range(saved_matches, ref_name_cnt);
+		return;
+	}
+	die("bad sha1 reference %s", av);
+}
+
+static int git_show_branch_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "showbranch.default")) {
+		if (!value)
+			return config_error_nonbool(var);
+		/*
+		 * default_arg is now passed to parse_options(), so we need to
+		 * mimic the real argv a bit better.
+		 */
+		if (!default_num) {
+			default_alloc = 20;
+			default_arg = xcalloc(default_alloc, sizeof(*default_arg));
+			default_arg[default_num++] = "show-branch";
+		} else if (default_alloc <= default_num + 1) {
+			default_alloc = default_alloc * 3 / 2 + 20;
+			default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc);
+		}
+		default_arg[default_num++] = xstrdup(value);
+		default_arg[default_num] = NULL;
+		return 0;
+	}
+
+	if (!strcmp(var, "color.showbranch")) {
+		showbranch_use_color = git_config_colorbool(var, value, -1);
+		return 0;
+	}
+
+	return git_color_default_config(var, value, cb);
+}
+
+static int omit_in_dense(struct commit *commit, struct commit **rev, int n)
+{
+	/* If the commit is tip of the named branches, do not
+	 * omit it.
+	 * Otherwise, if it is a merge that is reachable from only one
+	 * tip, it is not that interesting.
+	 */
+	int i, flag, count;
+	for (i = 0; i < n; i++)
+		if (rev[i] == commit)
+			return 0;
+	flag = commit->object.flags;
+	for (i = count = 0; i < n; i++) {
+		if (flag & (1u << (i + REV_SHIFT)))
+			count++;
+	}
+	if (count == 1)
+		return 1;
+	return 0;
+}
+
+static int reflog = 0;
+
+static int parse_reflog_param(const struct option *opt, const char *arg,
+			      int unset)
+{
+	char *ep;
+	const char **base = (const char **)opt->value;
+	if (!arg)
+		arg = "";
+	reflog = strtoul(arg, &ep, 10);
+	if (*ep == ',')
+		*base = ep + 1;
+	else if (*ep)
+		return error("unrecognized reflog param '%s'", arg);
+	else
+		*base = NULL;
+	if (reflog <= 0)
+		reflog = DEFAULT_REFLOG;
+	return 0;
+}
+
+int cmd_show_branch(int ac, const char **av, const char *prefix)
+{
+	struct commit *rev[MAX_REVS], *commit;
+	char *reflog_msg[MAX_REVS];
+	struct commit_list *list = NULL, *seen = NULL;
+	unsigned int rev_mask[MAX_REVS];
+	int num_rev, i, extra = 0;
+	int all_heads = 0, all_remotes = 0;
+	int all_mask, all_revs;
+	int lifo = 1;
+	char head[128];
+	const char *head_p;
+	int head_len;
+	unsigned char head_sha1[20];
+	int merge_base = 0;
+	int independent = 0;
+	int no_name = 0;
+	int sha1_name = 0;
+	int shown_merge_point = 0;
+	int with_current_branch = 0;
+	int head_at = -1;
+	int topics = 0;
+	int dense = 1;
+	const char *reflog_base = NULL;
+	struct option builtin_show_branch_options[] = {
+		OPT_BOOLEAN('a', "all", &all_heads,
+			    "show remote-tracking and local branches"),
+		OPT_BOOLEAN('r', "remotes", &all_remotes,
+			    "show remote-tracking branches"),
+		OPT__COLOR(&showbranch_use_color,
+			    "color '*!+-' corresponding to the branch"),
+		{ OPTION_INTEGER, 0, "more", &extra, "n",
+			    "show <n> more commits after the common ancestor",
+			    PARSE_OPT_OPTARG, NULL, (intptr_t)1 },
+		OPT_SET_INT(0, "list", &extra, "synonym to more=-1", -1),
+		OPT_BOOLEAN(0, "no-name", &no_name, "suppress naming strings"),
+		OPT_BOOLEAN(0, "current", &with_current_branch,
+			    "include the current branch"),
+		OPT_BOOLEAN(0, "sha1-name", &sha1_name,
+			    "name commits with their object names"),
+		OPT_BOOLEAN(0, "merge-base", &merge_base,
+			    "show possible merge bases"),
+		OPT_BOOLEAN(0, "independent", &independent,
+			    "show refs unreachable from any other ref"),
+		OPT_BOOLEAN(0, "topo-order", &lifo,
+			    "show commits in topological order"),
+		OPT_BOOLEAN(0, "topics", &topics,
+			    "show only commits not on the first branch"),
+		OPT_SET_INT(0, "sparse", &dense,
+			    "show merges reachable from only one tip", 0),
+		OPT_SET_INT(0, "date-order", &lifo,
+			    "show commits where no parent comes before its "
+			    "children", 0),
+		{ OPTION_CALLBACK, 'g', "reflog", &reflog_base, "<n>[,<base>]",
+			    "show <n> most recent ref-log entries starting at "
+			    "base",
+			    PARSE_OPT_OPTARG | PARSE_OPT_LITERAL_ARGHELP,
+			    parse_reflog_param },
+		OPT_END()
+	};
+
+	git_config(git_show_branch_config, NULL);
+
+	if (showbranch_use_color == -1)
+		showbranch_use_color = git_use_color_default;
+
+	/* If nothing is specified, try the default first */
+	if (ac == 1 && default_num) {
+		ac = default_num;
+		av = default_arg;
+	}
+
+	ac = parse_options(ac, av, prefix, builtin_show_branch_options,
+			   show_branch_usage, PARSE_OPT_STOP_AT_NON_OPTION);
+	if (all_heads)
+		all_remotes = 1;
+
+	if (extra || reflog) {
+		/* "listing" mode is incompatible with
+		 * independent nor merge-base modes.
+		 */
+		if (independent || merge_base)
+			usage_with_options(show_branch_usage,
+					   builtin_show_branch_options);
+		if (reflog && ((0 < extra) || all_heads || all_remotes))
+			/*
+			 * Asking for --more in reflog mode does not
+			 * make sense.  --list is Ok.
+			 *
+			 * Also --all and --remotes do not make sense either.
+			 */
+			die("--reflog is incompatible with --all, --remotes, "
+			    "--independent or --merge-base");
+	}
+
+	/* If nothing is specified, show all branches by default */
+	if (ac + all_heads + all_remotes == 0)
+		all_heads = 1;
+
+	if (reflog) {
+		unsigned char sha1[20];
+		char nth_desc[256];
+		char *ref;
+		int base = 0;
+
+		if (ac == 0) {
+			static const char *fake_av[2];
+			const char *refname;
+
+			refname = resolve_ref("HEAD", sha1, 1, NULL);
+			fake_av[0] = xstrdup(refname);
+			fake_av[1] = NULL;
+			av = fake_av;
+			ac = 1;
+		}
+		if (ac != 1)
+			die("--reflog option needs one branch name");
+
+		if (MAX_REVS < reflog)
+			die("Only %d entries can be shown at one time.",
+			    MAX_REVS);
+		if (!dwim_ref(*av, strlen(*av), sha1, &ref))
+			die("No such ref %s", *av);
+
+		/* Has the base been specified? */
+		if (reflog_base) {
+			char *ep;
+			base = strtoul(reflog_base, &ep, 10);
+			if (*ep) {
+				/* Ah, that is a date spec... */
+				unsigned long at;
+				at = approxidate(reflog_base);
+				read_ref_at(ref, at, -1, sha1, NULL,
+					    NULL, NULL, &base);
+			}
+		}
+
+		for (i = 0; i < reflog; i++) {
+			char *logmsg, *m;
+			const char *msg;
+			unsigned long timestamp;
+			int tz;
+
+			if (read_ref_at(ref, 0, base+i, sha1, &logmsg,
+					&timestamp, &tz, NULL)) {
+				reflog = i;
+				break;
+			}
+			msg = strchr(logmsg, '\t');
+			if (!msg)
+				msg = "(none)";
+			else
+				msg++;
+			m = xmalloc(strlen(msg) + 200);
+			sprintf(m, "(%s) %s",
+				show_date(timestamp, tz, 1),
+				msg);
+			reflog_msg[i] = m;
+			free(logmsg);
+			sprintf(nth_desc, "%s@{%d}", *av, base+i);
+			append_ref(nth_desc, sha1, 1);
+		}
+	}
+	else if (all_heads + all_remotes)
+		snarf_refs(all_heads, all_remotes);
+	else {
+		while (0 < ac) {
+			append_one_rev(*av);
+			ac--; av++;
+		}
+	}
+
+	head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
+	if (head_p) {
+		head_len = strlen(head_p);
+		memcpy(head, head_p, head_len + 1);
+	}
+	else {
+		head_len = 0;
+		head[0] = 0;
+	}
+
+	if (with_current_branch && head_p) {
+		int has_head = 0;
+		for (i = 0; !has_head && i < ref_name_cnt; i++) {
+			/* We are only interested in adding the branch
+			 * HEAD points at.
+			 */
+			if (rev_is_head(head,
+					head_len,
+					ref_name[i],
+					head_sha1, NULL))
+				has_head++;
+		}
+		if (!has_head) {
+			int offset = !prefixcmp(head, "refs/heads/") ? 11 : 0;
+			append_one_rev(head + offset);
+		}
+	}
+
+	if (!ref_name_cnt) {
+		fprintf(stderr, "No revs to be shown.\n");
+		exit(0);
+	}
+
+	for (num_rev = 0; ref_name[num_rev]; num_rev++) {
+		unsigned char revkey[20];
+		unsigned int flag = 1u << (num_rev + REV_SHIFT);
+
+		if (MAX_REVS <= num_rev)
+			die("cannot handle more than %d revs.", MAX_REVS);
+		if (get_sha1(ref_name[num_rev], revkey))
+			die("'%s' is not a valid ref.", ref_name[num_rev]);
+		commit = lookup_commit_reference(revkey);
+		if (!commit)
+			die("cannot find commit %s (%s)",
+			    ref_name[num_rev], revkey);
+		parse_commit(commit);
+		mark_seen(commit, &seen);
+
+		/* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
+		 * and so on.  REV_SHIFT bits from bit 0 are used for
+		 * internal bookkeeping.
+		 */
+		commit->object.flags |= flag;
+		if (commit->object.flags == flag)
+			insert_by_date(commit, &list);
+		rev[num_rev] = commit;
+	}
+	for (i = 0; i < num_rev; i++)
+		rev_mask[i] = rev[i]->object.flags;
+
+	if (0 <= extra)
+		join_revs(&list, &seen, num_rev, extra);
+
+	sort_by_date(&seen);
+
+	if (merge_base)
+		return show_merge_base(seen, num_rev);
+
+	if (independent)
+		return show_independent(rev, num_rev, ref_name, rev_mask);
+
+	/* Show list; --more=-1 means list-only */
+	if (1 < num_rev || extra < 0) {
+		for (i = 0; i < num_rev; i++) {
+			int j;
+			int is_head = rev_is_head(head,
+						  head_len,
+						  ref_name[i],
+						  head_sha1,
+						  rev[i]->object.sha1);
+			if (extra < 0)
+				printf("%c [%s] ",
+				       is_head ? '*' : ' ', ref_name[i]);
+			else {
+				for (j = 0; j < i; j++)
+					putchar(' ');
+				printf("%s%c%s [%s] ",
+				       get_color_code(i % COLUMN_COLORS_MAX),
+				       is_head ? '*' : '!',
+				       get_color_reset_code(), ref_name[i]);
+			}
+
+			if (!reflog) {
+				/* header lines never need name */
+				show_one_commit(rev[i], 1);
+			}
+			else
+				puts(reflog_msg[i]);
+
+			if (is_head)
+				head_at = i;
+		}
+		if (0 <= extra) {
+			for (i = 0; i < num_rev; i++)
+				putchar('-');
+			putchar('\n');
+		}
+	}
+	if (extra < 0)
+		exit(0);
+
+	/* Sort topologically */
+	sort_in_topological_order(&seen, lifo);
+
+	/* Give names to commits */
+	if (!sha1_name && !no_name)
+		name_commits(seen, rev, ref_name, num_rev);
+
+	all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
+	all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
+
+	while (seen) {
+		struct commit *commit = pop_one_commit(&seen);
+		int this_flag = commit->object.flags;
+		int is_merge_point = ((this_flag & all_revs) == all_revs);
+
+		shown_merge_point |= is_merge_point;
+
+		if (1 < num_rev) {
+			int is_merge = !!(commit->parents &&
+					  commit->parents->next);
+			if (topics &&
+			    !is_merge_point &&
+			    (this_flag & (1u << REV_SHIFT)))
+				continue;
+			if (dense && is_merge &&
+			    omit_in_dense(commit, rev, num_rev))
+				continue;
+			for (i = 0; i < num_rev; i++) {
+				int mark;
+				if (!(this_flag & (1u << (i + REV_SHIFT))))
+					mark = ' ';
+				else if (is_merge)
+					mark = '-';
+				else if (i == head_at)
+					mark = '*';
+				else
+					mark = '+';
+				printf("%s%c%s",
+				       get_color_code(i % COLUMN_COLORS_MAX),
+				       mark, get_color_reset_code());
+			}
+			putchar(' ');
+		}
+		show_one_commit(commit, no_name);
+
+		if (shown_merge_point && --extra < 0)
+			break;
+	}
+	return 0;
+}
diff --git a/builtin/show-ref.c b/builtin/show-ref.c
new file mode 100644
index 0000000..17ada88
--- /dev/null
+++ b/builtin/show-ref.c
@@ -0,0 +1,249 @@
+#include "builtin.h"
+#include "cache.h"
+#include "refs.h"
+#include "object.h"
+#include "tag.h"
+#include "string-list.h"
+#include "parse-options.h"
+
+static const char * const show_ref_usage[] = {
+	"git show-ref [-q|--quiet] [--verify] [--head] [-d|--dereference] [-s|--hash[=<n>]] [--abbrev[=<n>]] [--tags] [--heads] [--] [pattern*] ",
+	"git show-ref --exclude-existing[=pattern] < ref-list",
+	NULL
+};
+
+static int deref_tags, show_head, tags_only, heads_only, found_match, verify,
+	   quiet, hash_only, abbrev, exclude_arg;
+static const char **pattern;
+static const char *exclude_existing_arg;
+
+static void show_one(const char *refname, const unsigned char *sha1)
+{
+	const char *hex = find_unique_abbrev(sha1, abbrev);
+	if (hash_only)
+		printf("%s\n", hex);
+	else
+		printf("%s %s\n", hex, refname);
+}
+
+static int show_ref(const char *refname, const unsigned char *sha1, int flag, void *cbdata)
+{
+	struct object *obj;
+	const char *hex;
+	unsigned char peeled[20];
+
+	if (tags_only || heads_only) {
+		int match;
+
+		match = heads_only && !prefixcmp(refname, "refs/heads/");
+		match |= tags_only && !prefixcmp(refname, "refs/tags/");
+		if (!match)
+			return 0;
+	}
+	if (pattern) {
+		int reflen = strlen(refname);
+		const char **p = pattern, *m;
+		while ((m = *p++) != NULL) {
+			int len = strlen(m);
+			if (len > reflen)
+				continue;
+			if (memcmp(m, refname + reflen - len, len))
+				continue;
+			if (len == reflen)
+				goto match;
+			/* "--verify" requires an exact match */
+			if (verify)
+				continue;
+			if (refname[reflen - len - 1] == '/')
+				goto match;
+		}
+		return 0;
+	}
+
+match:
+	found_match++;
+
+	/* This changes the semantics slightly that even under quiet we
+	 * detect and return error if the repository is corrupt and
+	 * ref points at a nonexistent object.
+	 */
+	if (!has_sha1_file(sha1))
+		die("git show-ref: bad ref %s (%s)", refname,
+		    sha1_to_hex(sha1));
+
+	if (quiet)
+		return 0;
+
+	show_one(refname, sha1);
+
+	if (!deref_tags)
+		return 0;
+
+	if ((flag & REF_ISPACKED) && !peel_ref(refname, peeled)) {
+		if (!is_null_sha1(peeled)) {
+			hex = find_unique_abbrev(peeled, abbrev);
+			printf("%s %s^{}\n", hex, refname);
+		}
+	}
+	else {
+		obj = parse_object(sha1);
+		if (!obj)
+			die("git show-ref: bad ref %s (%s)", refname,
+			    sha1_to_hex(sha1));
+		if (obj->type == OBJ_TAG) {
+			obj = deref_tag(obj, refname, 0);
+			if (!obj)
+				die("git show-ref: bad tag at ref %s (%s)", refname,
+				    sha1_to_hex(sha1));
+			hex = find_unique_abbrev(obj->sha1, abbrev);
+			printf("%s %s^{}\n", hex, refname);
+		}
+	}
+	return 0;
+}
+
+static int add_existing(const char *refname, const unsigned char *sha1, int flag, void *cbdata)
+{
+	struct string_list *list = (struct string_list *)cbdata;
+	string_list_insert(refname, list);
+	return 0;
+}
+
+/*
+ * read "^(?:<anything>\s)?<refname>(?:\^\{\})?$" from the standard input,
+ * and
+ * (1) strip "^{}" at the end of line if any;
+ * (2) ignore if match is provided and does not head-match refname;
+ * (3) warn if refname is not a well-formed refname and skip;
+ * (4) ignore if refname is a ref that exists in the local repository;
+ * (5) otherwise output the line.
+ */
+static int exclude_existing(const char *match)
+{
+	static struct string_list existing_refs = { NULL, 0, 0, 0 };
+	char buf[1024];
+	int matchlen = match ? strlen(match) : 0;
+
+	for_each_ref(add_existing, &existing_refs);
+	while (fgets(buf, sizeof(buf), stdin)) {
+		char *ref;
+		int len = strlen(buf);
+
+		if (len > 0 && buf[len - 1] == '\n')
+			buf[--len] = '\0';
+		if (3 <= len && !strcmp(buf + len - 3, "^{}")) {
+			len -= 3;
+			buf[len] = '\0';
+		}
+		for (ref = buf + len; buf < ref; ref--)
+			if (isspace(ref[-1]))
+				break;
+		if (match) {
+			int reflen = buf + len - ref;
+			if (reflen < matchlen)
+				continue;
+			if (strncmp(ref, match, matchlen))
+				continue;
+		}
+		if (check_ref_format(ref)) {
+			warning("ref '%s' ignored", ref);
+			continue;
+		}
+		if (!string_list_has_string(&existing_refs, ref)) {
+			printf("%s\n", buf);
+		}
+	}
+	return 0;
+}
+
+static int hash_callback(const struct option *opt, const char *arg, int unset)
+{
+	hash_only = 1;
+	/* Use full length SHA1 if no argument */
+	if (!arg)
+		return 0;
+	return parse_opt_abbrev_cb(opt, arg, unset);
+}
+
+static int exclude_existing_callback(const struct option *opt, const char *arg,
+				     int unset)
+{
+	exclude_arg = 1;
+	*(const char **)opt->value = arg;
+	return 0;
+}
+
+static int help_callback(const struct option *opt, const char *arg, int unset)
+{
+	return -1;
+}
+
+static const struct option show_ref_options[] = {
+	OPT_BOOLEAN(0, "tags", &tags_only, "only show tags (can be combined with heads)"),
+	OPT_BOOLEAN(0, "heads", &heads_only, "only show heads (can be combined with tags)"),
+	OPT_BOOLEAN(0, "verify", &verify, "stricter reference checking, "
+		    "requires exact ref path"),
+	{ OPTION_BOOLEAN, 'h', NULL, &show_head, NULL,
+	  "show the HEAD reference",
+	  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
+	OPT_BOOLEAN(0, "head", &show_head, "show the HEAD reference"),
+	OPT_BOOLEAN('d', "dereference", &deref_tags,
+		    "dereference tags into object IDs"),
+	{ OPTION_CALLBACK, 's', "hash", &abbrev, "n",
+	  "only show SHA1 hash using <n> digits",
+	  PARSE_OPT_OPTARG, &hash_callback },
+	OPT__ABBREV(&abbrev),
+	OPT__QUIET(&quiet),
+	{ OPTION_CALLBACK, 0, "exclude-existing", &exclude_existing_arg,
+	  "pattern", "show refs from stdin that aren't in local repository",
+	  PARSE_OPT_OPTARG | PARSE_OPT_NONEG, exclude_existing_callback },
+	{ OPTION_CALLBACK, 0, "help-all", NULL, NULL, "show usage",
+	  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
+	OPT_END()
+};
+
+int cmd_show_ref(int argc, const char **argv, const char *prefix)
+{
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage_with_options(show_ref_usage, show_ref_options);
+
+	argc = parse_options(argc, argv, prefix, show_ref_options,
+			     show_ref_usage, PARSE_OPT_NO_INTERNAL_HELP);
+
+	if (exclude_arg)
+		return exclude_existing(exclude_existing_arg);
+
+	pattern = argv;
+	if (!*pattern)
+		pattern = NULL;
+
+	if (verify) {
+		if (!pattern)
+			die("--verify requires a reference");
+		while (*pattern) {
+			unsigned char sha1[20];
+
+			if (!prefixcmp(*pattern, "refs/") &&
+			    resolve_ref(*pattern, sha1, 1, NULL)) {
+				if (!quiet)
+					show_one(*pattern, sha1);
+			}
+			else if (!quiet)
+				die("'%s' - not a valid ref", *pattern);
+			else
+				return 1;
+			pattern++;
+		}
+		return 0;
+	}
+
+	if (show_head)
+		head_ref(show_ref, NULL);
+	for_each_ref(show_ref, NULL);
+	if (!found_match) {
+		if (verify && !quiet)
+			die("No match");
+		return 1;
+	}
+	return 0;
+}
diff --git a/builtin/stripspace.c b/builtin/stripspace.c
new file mode 100644
index 0000000..4d3b93f
--- /dev/null
+++ b/builtin/stripspace.c
@@ -0,0 +1,90 @@
+#include "builtin.h"
+#include "cache.h"
+
+/*
+ * Returns the length of a line, without trailing spaces.
+ *
+ * If the line ends with newline, it will be removed too.
+ */
+static size_t cleanup(char *line, size_t len)
+{
+	while (len) {
+		unsigned char c = line[len - 1];
+		if (!isspace(c))
+			break;
+		len--;
+	}
+
+	return len;
+}
+
+/*
+ * Remove empty lines from the beginning and end
+ * and also trailing spaces from every line.
+ *
+ * Note that the buffer will not be NUL-terminated.
+ *
+ * Turn multiple consecutive empty lines between paragraphs
+ * into just one empty line.
+ *
+ * If the input has only empty lines and spaces,
+ * no output will be produced.
+ *
+ * If last line does not have a newline at the end, one is added.
+ *
+ * Enable skip_comments to skip every line starting with "#".
+ */
+void stripspace(struct strbuf *sb, int skip_comments)
+{
+	int empties = 0;
+	size_t i, j, len, newlen;
+	char *eol;
+
+	/* We may have to add a newline. */
+	strbuf_grow(sb, 1);
+
+	for (i = j = 0; i < sb->len; i += len, j += newlen) {
+		eol = memchr(sb->buf + i, '\n', sb->len - i);
+		len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
+
+		if (skip_comments && len && sb->buf[i] == '#') {
+			newlen = 0;
+			continue;
+		}
+		newlen = cleanup(sb->buf + i, len);
+
+		/* Not just an empty line? */
+		if (newlen) {
+			if (empties > 0 && j > 0)
+				sb->buf[j++] = '\n';
+			empties = 0;
+			memmove(sb->buf + j, sb->buf + i, newlen);
+			sb->buf[newlen + j++] = '\n';
+		} else {
+			empties++;
+		}
+	}
+
+	strbuf_setlen(sb, j);
+}
+
+int cmd_stripspace(int argc, const char **argv, const char *prefix)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int strip_comments = 0;
+
+	if (argc == 2 && (!strcmp(argv[1], "-s") ||
+				!strcmp(argv[1], "--strip-comments")))
+		strip_comments = 1;
+	else if (argc > 1)
+		usage("git stripspace [-s | --strip-comments] < <stream>");
+
+	if (strbuf_read(&buf, 0, 1024) < 0)
+		die_errno("could not read the input");
+
+	stripspace(&buf, strip_comments);
+
+	write_or_die(1, buf.buf, buf.len);
+	strbuf_release(&buf);
+	return 0;
+}
diff --git a/builtin/symbolic-ref.c b/builtin/symbolic-ref.c
new file mode 100644
index 0000000..ca855a5
--- /dev/null
+++ b/builtin/symbolic-ref.c
@@ -0,0 +1,57 @@
+#include "builtin.h"
+#include "cache.h"
+#include "refs.h"
+#include "parse-options.h"
+
+static const char * const git_symbolic_ref_usage[] = {
+	"git symbolic-ref [options] name [ref]",
+	NULL
+};
+
+static void check_symref(const char *HEAD, int quiet)
+{
+	unsigned char sha1[20];
+	int flag;
+	const char *refs_heads_master = resolve_ref(HEAD, sha1, 0, &flag);
+
+	if (!refs_heads_master)
+		die("No such ref: %s", HEAD);
+	else if (!(flag & REF_ISSYMREF)) {
+		if (!quiet)
+			die("ref %s is not a symbolic ref", HEAD);
+		else
+			exit(1);
+	}
+	puts(refs_heads_master);
+}
+
+int cmd_symbolic_ref(int argc, const char **argv, const char *prefix)
+{
+	int quiet = 0;
+	const char *msg = NULL;
+	struct option options[] = {
+		OPT__QUIET(&quiet),
+		OPT_STRING('m', NULL, &msg, "reason", "reason of the update"),
+		OPT_END(),
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, prefix, options,
+			     git_symbolic_ref_usage, 0);
+	if (msg &&!*msg)
+		die("Refusing to perform update with empty message");
+	switch (argc) {
+	case 1:
+		check_symref(argv[0], quiet);
+		break;
+	case 2:
+		if (!strcmp(argv[0], "HEAD") &&
+		    prefixcmp(argv[1], "refs/"))
+			die("Refusing to point HEAD outside of refs/");
+		create_symref(argv[0], argv[1], msg);
+		break;
+	default:
+		usage_with_options(git_symbolic_ref_usage, options);
+	}
+	return 0;
+}
diff --git a/builtin/tag.c b/builtin/tag.c
new file mode 100644
index 0000000..4ef1c4f
--- /dev/null
+++ b/builtin/tag.c
@@ -0,0 +1,487 @@
+/*
+ * Builtin "git tag"
+ *
+ * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
+ *                    Carlos Rica <jasampler@gmail.com>
+ * Based on git-tag.sh and mktag.c by Linus Torvalds.
+ */
+
+#include "cache.h"
+#include "builtin.h"
+#include "refs.h"
+#include "tag.h"
+#include "run-command.h"
+#include "parse-options.h"
+
+static const char * const git_tag_usage[] = {
+	"git tag [-a|-s|-u <key-id>] [-f] [-m <msg>|-F <file>] <tagname> [<head>]",
+	"git tag -d <tagname>...",
+	"git tag -l [-n[<num>]] [<pattern>]",
+	"git tag -v <tagname>...",
+	NULL
+};
+
+static char signingkey[1000];
+
+struct tag_filter {
+	const char *pattern;
+	int lines;
+	struct commit_list *with_commit;
+};
+
+#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
+
+static int show_reference(const char *refname, const unsigned char *sha1,
+			  int flag, void *cb_data)
+{
+	struct tag_filter *filter = cb_data;
+
+	if (!fnmatch(filter->pattern, refname, 0)) {
+		int i;
+		unsigned long size;
+		enum object_type type;
+		char *buf, *sp, *eol;
+		size_t len;
+
+		if (filter->with_commit) {
+			struct commit *commit;
+
+			commit = lookup_commit_reference_gently(sha1, 1);
+			if (!commit)
+				return 0;
+			if (!is_descendant_of(commit, filter->with_commit))
+				return 0;
+		}
+
+		if (!filter->lines) {
+			printf("%s\n", refname);
+			return 0;
+		}
+		printf("%-15s ", refname);
+
+		buf = read_sha1_file(sha1, &type, &size);
+		if (!buf || !size)
+			return 0;
+
+		/* skip header */
+		sp = strstr(buf, "\n\n");
+		if (!sp) {
+			free(buf);
+			return 0;
+		}
+		/* only take up to "lines" lines, and strip the signature */
+		for (i = 0, sp += 2;
+				i < filter->lines && sp < buf + size &&
+				prefixcmp(sp, PGP_SIGNATURE "\n");
+				i++) {
+			if (i)
+				printf("\n    ");
+			eol = memchr(sp, '\n', size - (sp - buf));
+			len = eol ? eol - sp : size - (sp - buf);
+			fwrite(sp, len, 1, stdout);
+			if (!eol)
+				break;
+			sp = eol + 1;
+		}
+		putchar('\n');
+		free(buf);
+	}
+
+	return 0;
+}
+
+static int list_tags(const char *pattern, int lines,
+			struct commit_list *with_commit)
+{
+	struct tag_filter filter;
+
+	if (pattern == NULL)
+		pattern = "*";
+
+	filter.pattern = pattern;
+	filter.lines = lines;
+	filter.with_commit = with_commit;
+
+	for_each_tag_ref(show_reference, (void *) &filter);
+
+	return 0;
+}
+
+typedef int (*each_tag_name_fn)(const char *name, const char *ref,
+				const unsigned char *sha1);
+
+static int for_each_tag_name(const char **argv, each_tag_name_fn fn)
+{
+	const char **p;
+	char ref[PATH_MAX];
+	int had_error = 0;
+	unsigned char sha1[20];
+
+	for (p = argv; *p; p++) {
+		if (snprintf(ref, sizeof(ref), "refs/tags/%s", *p)
+					>= sizeof(ref)) {
+			error("tag name too long: %.*s...", 50, *p);
+			had_error = 1;
+			continue;
+		}
+		if (!resolve_ref(ref, sha1, 1, NULL)) {
+			error("tag '%s' not found.", *p);
+			had_error = 1;
+			continue;
+		}
+		if (fn(*p, ref, sha1))
+			had_error = 1;
+	}
+	return had_error;
+}
+
+static int delete_tag(const char *name, const char *ref,
+				const unsigned char *sha1)
+{
+	if (delete_ref(ref, sha1, 0))
+		return 1;
+	printf("Deleted tag '%s' (was %s)\n", name, find_unique_abbrev(sha1, DEFAULT_ABBREV));
+	return 0;
+}
+
+static int verify_tag(const char *name, const char *ref,
+				const unsigned char *sha1)
+{
+	const char *argv_verify_tag[] = {"git-verify-tag",
+					"-v", "SHA1_HEX", NULL};
+	argv_verify_tag[2] = sha1_to_hex(sha1);
+
+	if (run_command_v_opt(argv_verify_tag, 0))
+		return error("could not verify the tag '%s'", name);
+	return 0;
+}
+
+static int do_sign(struct strbuf *buffer)
+{
+	struct child_process gpg;
+	const char *args[4];
+	char *bracket;
+	int len;
+	int i, j;
+
+	if (!*signingkey) {
+		if (strlcpy(signingkey, git_committer_info(IDENT_ERROR_ON_NO_NAME),
+				sizeof(signingkey)) > sizeof(signingkey) - 1)
+			return error("committer info too long.");
+		bracket = strchr(signingkey, '>');
+		if (bracket)
+			bracket[1] = '\0';
+	}
+
+	/* When the username signingkey is bad, program could be terminated
+	 * because gpg exits without reading and then write gets SIGPIPE. */
+	signal(SIGPIPE, SIG_IGN);
+
+	memset(&gpg, 0, sizeof(gpg));
+	gpg.argv = args;
+	gpg.in = -1;
+	gpg.out = -1;
+	args[0] = "gpg";
+	args[1] = "-bsau";
+	args[2] = signingkey;
+	args[3] = NULL;
+
+	if (start_command(&gpg))
+		return error("could not run gpg.");
+
+	if (write_in_full(gpg.in, buffer->buf, buffer->len) != buffer->len) {
+		close(gpg.in);
+		close(gpg.out);
+		finish_command(&gpg);
+		return error("gpg did not accept the tag data");
+	}
+	close(gpg.in);
+	len = strbuf_read(buffer, gpg.out, 1024);
+	close(gpg.out);
+
+	if (finish_command(&gpg) || !len || len < 0)
+		return error("gpg failed to sign the tag");
+
+	/* Strip CR from the line endings, in case we are on Windows. */
+	for (i = j = 0; i < buffer->len; i++)
+		if (buffer->buf[i] != '\r') {
+			if (i != j)
+				buffer->buf[j] = buffer->buf[i];
+			j++;
+		}
+	strbuf_setlen(buffer, j);
+
+	return 0;
+}
+
+static const char tag_template[] =
+	"\n"
+	"#\n"
+	"# Write a tag message\n"
+	"#\n";
+
+static void set_signingkey(const char *value)
+{
+	if (strlcpy(signingkey, value, sizeof(signingkey)) >= sizeof(signingkey))
+		die("signing key value too long (%.10s...)", value);
+}
+
+static int git_tag_config(const char *var, const char *value, void *cb)
+{
+	if (!strcmp(var, "user.signingkey")) {
+		if (!value)
+			return config_error_nonbool(var);
+		set_signingkey(value);
+		return 0;
+	}
+
+	return git_default_config(var, value, cb);
+}
+
+static void write_tag_body(int fd, const unsigned char *sha1)
+{
+	unsigned long size;
+	enum object_type type;
+	char *buf, *sp, *eob;
+	size_t len;
+
+	buf = read_sha1_file(sha1, &type, &size);
+	if (!buf)
+		return;
+	/* skip header */
+	sp = strstr(buf, "\n\n");
+
+	if (!sp || !size || type != OBJ_TAG) {
+		free(buf);
+		return;
+	}
+	sp += 2; /* skip the 2 LFs */
+	eob = strstr(sp, "\n" PGP_SIGNATURE "\n");
+	if (eob)
+		len = eob - sp;
+	else
+		len = buf + size - sp;
+	write_or_die(fd, sp, len);
+
+	free(buf);
+}
+
+static int build_tag_object(struct strbuf *buf, int sign, unsigned char *result)
+{
+	if (sign && do_sign(buf) < 0)
+		return error("unable to sign the tag");
+	if (write_sha1_file(buf->buf, buf->len, tag_type, result) < 0)
+		return error("unable to write tag file");
+	return 0;
+}
+
+static void create_tag(const unsigned char *object, const char *tag,
+		       struct strbuf *buf, int message, int sign,
+		       unsigned char *prev, unsigned char *result)
+{
+	enum object_type type;
+	char header_buf[1024];
+	int header_len;
+	char *path = NULL;
+
+	type = sha1_object_info(object, NULL);
+	if (type <= OBJ_NONE)
+	    die("bad object type.");
+
+	header_len = snprintf(header_buf, sizeof(header_buf),
+			  "object %s\n"
+			  "type %s\n"
+			  "tag %s\n"
+			  "tagger %s\n\n",
+			  sha1_to_hex(object),
+			  typename(type),
+			  tag,
+			  git_committer_info(IDENT_ERROR_ON_NO_NAME));
+
+	if (header_len > sizeof(header_buf) - 1)
+		die("tag header too big.");
+
+	if (!message) {
+		int fd;
+
+		/* write the template message before editing: */
+		path = git_pathdup("TAG_EDITMSG");
+		fd = open(path, O_CREAT | O_TRUNC | O_WRONLY, 0600);
+		if (fd < 0)
+			die_errno("could not create file '%s'", path);
+
+		if (!is_null_sha1(prev))
+			write_tag_body(fd, prev);
+		else
+			write_or_die(fd, tag_template, strlen(tag_template));
+		close(fd);
+
+		if (launch_editor(path, buf, NULL)) {
+			fprintf(stderr,
+			"Please supply the message using either -m or -F option.\n");
+			exit(1);
+		}
+	}
+
+	stripspace(buf, 1);
+
+	if (!message && !buf->len)
+		die("no tag message?");
+
+	strbuf_insert(buf, 0, header_buf, header_len);
+
+	if (build_tag_object(buf, sign, result) < 0) {
+		if (path)
+			fprintf(stderr, "The tag message has been left in %s\n",
+				path);
+		exit(128);
+	}
+	if (path) {
+		unlink_or_warn(path);
+		free(path);
+	}
+}
+
+struct msg_arg {
+	int given;
+	struct strbuf buf;
+};
+
+static int parse_msg_arg(const struct option *opt, const char *arg, int unset)
+{
+	struct msg_arg *msg = opt->value;
+
+	if (!arg)
+		return -1;
+	if (msg->buf.len)
+		strbuf_addstr(&(msg->buf), "\n\n");
+	strbuf_addstr(&(msg->buf), arg);
+	msg->given = 1;
+	return 0;
+}
+
+int cmd_tag(int argc, const char **argv, const char *prefix)
+{
+	struct strbuf buf = STRBUF_INIT;
+	unsigned char object[20], prev[20];
+	char ref[PATH_MAX];
+	const char *object_ref, *tag;
+	struct ref_lock *lock;
+
+	int annotate = 0, sign = 0, force = 0, lines = -1,
+		list = 0, delete = 0, verify = 0;
+	const char *msgfile = NULL, *keyid = NULL;
+	struct msg_arg msg = { 0, STRBUF_INIT };
+	struct commit_list *with_commit = NULL;
+	struct option options[] = {
+		OPT_BOOLEAN('l', NULL, &list, "list tag names"),
+		{ OPTION_INTEGER, 'n', NULL, &lines, "n",
+				"print <n> lines of each tag message",
+				PARSE_OPT_OPTARG, NULL, 1 },
+		OPT_BOOLEAN('d', NULL, &delete, "delete tags"),
+		OPT_BOOLEAN('v', NULL, &verify, "verify tags"),
+
+		OPT_GROUP("Tag creation options"),
+		OPT_BOOLEAN('a', NULL, &annotate,
+					"annotated tag, needs a message"),
+		OPT_CALLBACK('m', NULL, &msg, "msg",
+			     "message for the tag", parse_msg_arg),
+		OPT_FILENAME('F', NULL, &msgfile, "message in a file"),
+		OPT_BOOLEAN('s', NULL, &sign, "annotated and GPG-signed tag"),
+		OPT_STRING('u', NULL, &keyid, "key-id",
+					"use another key to sign the tag"),
+		OPT_BOOLEAN('f', "force", &force, "replace the tag if exists"),
+
+		OPT_GROUP("Tag listing options"),
+		{
+			OPTION_CALLBACK, 0, "contains", &with_commit, "commit",
+			"print only tags that contain the commit",
+			PARSE_OPT_LASTARG_DEFAULT,
+			parse_opt_with_commit, (intptr_t)"HEAD",
+		},
+		OPT_END()
+	};
+
+	git_config(git_tag_config, NULL);
+
+	argc = parse_options(argc, argv, prefix, options, git_tag_usage, 0);
+
+	if (keyid) {
+		sign = 1;
+		set_signingkey(keyid);
+	}
+	if (sign)
+		annotate = 1;
+	if (argc == 0 && !(delete || verify))
+		list = 1;
+
+	if ((annotate || msg.given || msgfile || force) &&
+	    (list || delete || verify))
+		usage_with_options(git_tag_usage, options);
+
+	if (list + delete + verify > 1)
+		usage_with_options(git_tag_usage, options);
+	if (list)
+		return list_tags(argv[0], lines == -1 ? 0 : lines,
+				 with_commit);
+	if (lines != -1)
+		die("-n option is only allowed with -l.");
+	if (with_commit)
+		die("--contains option is only allowed with -l.");
+	if (delete)
+		return for_each_tag_name(argv, delete_tag);
+	if (verify)
+		return for_each_tag_name(argv, verify_tag);
+
+	if (msg.given || msgfile) {
+		if (msg.given && msgfile)
+			die("only one -F or -m option is allowed.");
+		annotate = 1;
+		if (msg.given)
+			strbuf_addbuf(&buf, &(msg.buf));
+		else {
+			if (!strcmp(msgfile, "-")) {
+				if (strbuf_read(&buf, 0, 1024) < 0)
+					die_errno("cannot read '%s'", msgfile);
+			} else {
+				if (strbuf_read_file(&buf, msgfile, 1024) < 0)
+					die_errno("could not open or read '%s'",
+						msgfile);
+			}
+		}
+	}
+
+	tag = argv[0];
+
+	object_ref = argc == 2 ? argv[1] : "HEAD";
+	if (argc > 2)
+		die("too many params");
+
+	if (get_sha1(object_ref, object))
+		die("Failed to resolve '%s' as a valid ref.", object_ref);
+
+	if (snprintf(ref, sizeof(ref), "refs/tags/%s", tag) > sizeof(ref) - 1)
+		die("tag name too long: %.*s...", 50, tag);
+	if (check_ref_format(ref))
+		die("'%s' is not a valid tag name.", tag);
+
+	if (!resolve_ref(ref, prev, 1, NULL))
+		hashclr(prev);
+	else if (!force)
+		die("tag '%s' already exists", tag);
+
+	if (annotate)
+		create_tag(object, tag, &buf, msg.given || msgfile,
+			   sign, prev, object);
+
+	lock = lock_any_ref_for_update(ref, prev, 0);
+	if (!lock)
+		die("%s: cannot lock the ref", ref);
+	if (write_ref_sha1(lock, object, NULL) < 0)
+		die("%s: cannot update the ref", ref);
+	if (force && hashcmp(prev, object))
+		printf("Updated tag '%s' (was %s)\n", tag, find_unique_abbrev(prev, DEFAULT_ABBREV));
+
+	strbuf_release(&buf);
+	return 0;
+}
diff --git a/builtin/tar-tree.c b/builtin/tar-tree.c
new file mode 100644
index 0000000..3f1e701
--- /dev/null
+++ b/builtin/tar-tree.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2005, 2006 Rene Scharfe
+ */
+#include "cache.h"
+#include "commit.h"
+#include "tar.h"
+#include "builtin.h"
+#include "quote.h"
+
+static const char tar_tree_usage[] =
+"git tar-tree [--remote=<repo>] <tree-ish> [basedir]\n"
+"*** Note that this command is now deprecated; use \"git archive\" instead.";
+
+static const char builtin_get_tar_commit_id_usage[] =
+"git get-tar-commit-id < <tarfile>";
+
+int cmd_tar_tree(int argc, const char **argv, const char *prefix)
+{
+	/*
+	 * "git tar-tree" is now a wrapper around "git archive --format=tar"
+	 *
+	 * $0 --remote=<repo> arg... ==>
+	 *	git archive --format=tar --remote=<repo> arg...
+	 * $0 tree-ish ==>
+	 *	git archive --format=tar tree-ish
+	 * $0 tree-ish basedir ==>
+	 * 	git archive --format-tar --prefix=basedir tree-ish
+	 */
+	int i;
+	const char **nargv = xcalloc(sizeof(*nargv), argc + 3);
+	char *basedir_arg;
+	int nargc = 0;
+
+	nargv[nargc++] = "archive";
+	nargv[nargc++] = "--format=tar";
+
+	if (2 <= argc && !prefixcmp(argv[1], "--remote=")) {
+		nargv[nargc++] = argv[1];
+		argv++;
+		argc--;
+	}
+
+	/*
+	 * Because it's just a compatibility wrapper, tar-tree supports only
+	 * the old behaviour of reading attributes from the work tree.
+	 */
+	nargv[nargc++] = "--worktree-attributes";
+
+	switch (argc) {
+	default:
+		usage(tar_tree_usage);
+		break;
+	case 3:
+		/* base-path */
+		basedir_arg = xmalloc(strlen(argv[2]) + 11);
+		sprintf(basedir_arg, "--prefix=%s/", argv[2]);
+		nargv[nargc++] = basedir_arg;
+		/* fallthru */
+	case 2:
+		/* tree-ish */
+		nargv[nargc++] = argv[1];
+	}
+	nargv[nargc] = NULL;
+
+	fprintf(stderr,
+		"*** \"git tar-tree\" is now deprecated.\n"
+		"*** Running \"git archive\" instead.\n***");
+	for (i = 0; i < nargc; i++) {
+		fputc(' ', stderr);
+		sq_quote_print(stderr, nargv[i]);
+	}
+	fputc('\n', stderr);
+	return cmd_archive(nargc, nargv, prefix);
+}
+
+/* ustar header + extended global header content */
+#define RECORDSIZE	(512)
+#define HEADERSIZE (2 * RECORDSIZE)
+
+int cmd_get_tar_commit_id(int argc, const char **argv, const char *prefix)
+{
+	char buffer[HEADERSIZE];
+	struct ustar_header *header = (struct ustar_header *)buffer;
+	char *content = buffer + RECORDSIZE;
+	ssize_t n;
+
+	if (argc != 1)
+		usage(builtin_get_tar_commit_id_usage);
+
+	n = read_in_full(0, buffer, HEADERSIZE);
+	if (n < HEADERSIZE)
+		die("git get-tar-commit-id: read error");
+	if (header->typeflag[0] != 'g')
+		return 1;
+	if (memcmp(content, "52 comment=", 11))
+		return 1;
+
+	n = write_in_full(1, content + 11, 41);
+	if (n < 41)
+		die_errno("git get-tar-commit-id: write error");
+
+	return 0;
+}
diff --git a/builtin/unpack-file.c b/builtin/unpack-file.c
new file mode 100644
index 0000000..608590a
--- /dev/null
+++ b/builtin/unpack-file.c
@@ -0,0 +1,38 @@
+#include "cache.h"
+#include "blob.h"
+#include "exec_cmd.h"
+
+static char *create_temp_file(unsigned char *sha1)
+{
+	static char path[50];
+	void *buf;
+	enum object_type type;
+	unsigned long size;
+	int fd;
+
+	buf = read_sha1_file(sha1, &type, &size);
+	if (!buf || type != OBJ_BLOB)
+		die("unable to read blob object %s", sha1_to_hex(sha1));
+
+	strcpy(path, ".merge_file_XXXXXX");
+	fd = xmkstemp(path);
+	if (write_in_full(fd, buf, size) != size)
+		die_errno("unable to write temp-file");
+	close(fd);
+	return path;
+}
+
+int cmd_unpack_file(int argc, const char **argv, const char *prefix)
+{
+	unsigned char sha1[20];
+
+	if (argc != 2 || !strcmp(argv[1], "-h"))
+		usage("git unpack-file <sha1>");
+	if (get_sha1(argv[1], sha1))
+		die("Not a valid object name %s", argv[1]);
+
+	git_config(git_default_config, NULL);
+
+	puts(create_temp_file(sha1));
+	return 0;
+}
diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
new file mode 100644
index 0000000..685566e
--- /dev/null
+++ b/builtin/unpack-objects.c
@@ -0,0 +1,568 @@
+#include "builtin.h"
+#include "cache.h"
+#include "object.h"
+#include "delta.h"
+#include "pack.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "progress.h"
+#include "decorate.h"
+#include "fsck.h"
+
+static int dry_run, quiet, recover, has_errors, strict;
+static const char unpack_usage[] = "git unpack-objects [-n] [-q] [-r] [--strict] < pack-file";
+
+/* We always read in 4kB chunks. */
+static unsigned char buffer[4096];
+static unsigned int offset, len;
+static off_t consumed_bytes;
+static git_SHA_CTX ctx;
+
+/*
+ * When running under --strict mode, objects whose reachability are
+ * suspect are kept in core without getting written in the object
+ * store.
+ */
+struct obj_buffer {
+	char *buffer;
+	unsigned long size;
+};
+
+static struct decoration obj_decorate;
+
+static struct obj_buffer *lookup_object_buffer(struct object *base)
+{
+	return lookup_decoration(&obj_decorate, base);
+}
+
+static void add_object_buffer(struct object *object, char *buffer, unsigned long size)
+{
+	struct obj_buffer *obj;
+	obj = xcalloc(1, sizeof(struct obj_buffer));
+	obj->buffer = buffer;
+	obj->size = size;
+	if (add_decoration(&obj_decorate, object, obj))
+		die("object %s tried to add buffer twice!", sha1_to_hex(object->sha1));
+}
+
+/*
+ * Make sure at least "min" bytes are available in the buffer, and
+ * return the pointer to the buffer.
+ */
+static void *fill(int min)
+{
+	if (min <= len)
+		return buffer + offset;
+	if (min > sizeof(buffer))
+		die("cannot fill %d bytes", min);
+	if (offset) {
+		git_SHA1_Update(&ctx, buffer, offset);
+		memmove(buffer, buffer + offset, len);
+		offset = 0;
+	}
+	do {
+		ssize_t ret = xread(0, buffer + len, sizeof(buffer) - len);
+		if (ret <= 0) {
+			if (!ret)
+				die("early EOF");
+			die_errno("read error on input");
+		}
+		len += ret;
+	} while (len < min);
+	return buffer;
+}
+
+static void use(int bytes)
+{
+	if (bytes > len)
+		die("used more bytes than were available");
+	len -= bytes;
+	offset += bytes;
+
+	/* make sure off_t is sufficiently large not to wrap */
+	if (consumed_bytes > consumed_bytes + bytes)
+		die("pack too large for current definition of off_t");
+	consumed_bytes += bytes;
+}
+
+static void *get_data(unsigned long size)
+{
+	z_stream stream;
+	void *buf = xmalloc(size);
+
+	memset(&stream, 0, sizeof(stream));
+
+	stream.next_out = buf;
+	stream.avail_out = size;
+	stream.next_in = fill(1);
+	stream.avail_in = len;
+	git_inflate_init(&stream);
+
+	for (;;) {
+		int ret = git_inflate(&stream, 0);
+		use(len - stream.avail_in);
+		if (stream.total_out == size && ret == Z_STREAM_END)
+			break;
+		if (ret != Z_OK) {
+			error("inflate returned %d\n", ret);
+			free(buf);
+			buf = NULL;
+			if (!recover)
+				exit(1);
+			has_errors = 1;
+			break;
+		}
+		stream.next_in = fill(1);
+		stream.avail_in = len;
+	}
+	git_inflate_end(&stream);
+	return buf;
+}
+
+struct delta_info {
+	unsigned char base_sha1[20];
+	unsigned nr;
+	off_t base_offset;
+	unsigned long size;
+	void *delta;
+	struct delta_info *next;
+};
+
+static struct delta_info *delta_list;
+
+static void add_delta_to_list(unsigned nr, unsigned const char *base_sha1,
+			      off_t base_offset,
+			      void *delta, unsigned long size)
+{
+	struct delta_info *info = xmalloc(sizeof(*info));
+
+	hashcpy(info->base_sha1, base_sha1);
+	info->base_offset = base_offset;
+	info->size = size;
+	info->delta = delta;
+	info->nr = nr;
+	info->next = delta_list;
+	delta_list = info;
+}
+
+struct obj_info {
+	off_t offset;
+	unsigned char sha1[20];
+	struct object *obj;
+};
+
+#define FLAG_OPEN (1u<<20)
+#define FLAG_WRITTEN (1u<<21)
+
+static struct obj_info *obj_list;
+static unsigned nr_objects;
+
+/*
+ * Called only from check_object() after it verified this object
+ * is Ok.
+ */
+static void write_cached_object(struct object *obj)
+{
+	unsigned char sha1[20];
+	struct obj_buffer *obj_buf = lookup_object_buffer(obj);
+	if (write_sha1_file(obj_buf->buffer, obj_buf->size, typename(obj->type), sha1) < 0)
+		die("failed to write object %s", sha1_to_hex(obj->sha1));
+	obj->flags |= FLAG_WRITTEN;
+}
+
+/*
+ * At the very end of the processing, write_rest() scans the objects
+ * that have reachability requirements and calls this function.
+ * Verify its reachability and validity recursively and write it out.
+ */
+static int check_object(struct object *obj, int type, void *data)
+{
+	if (!obj)
+		return 1;
+
+	if (obj->flags & FLAG_WRITTEN)
+		return 0;
+
+	if (type != OBJ_ANY && obj->type != type)
+		die("object type mismatch");
+
+	if (!(obj->flags & FLAG_OPEN)) {
+		unsigned long size;
+		int type = sha1_object_info(obj->sha1, &size);
+		if (type != obj->type || type <= 0)
+			die("object of unexpected type");
+		obj->flags |= FLAG_WRITTEN;
+		return 0;
+	}
+
+	if (fsck_object(obj, 1, fsck_error_function))
+		die("Error in object");
+	if (fsck_walk(obj, check_object, NULL))
+		die("Error on reachable objects of %s", sha1_to_hex(obj->sha1));
+	write_cached_object(obj);
+	return 0;
+}
+
+static void write_rest(void)
+{
+	unsigned i;
+	for (i = 0; i < nr_objects; i++) {
+		if (obj_list[i].obj)
+			check_object(obj_list[i].obj, OBJ_ANY, NULL);
+	}
+}
+
+static void added_object(unsigned nr, enum object_type type,
+			 void *data, unsigned long size);
+
+/*
+ * Write out nr-th object from the list, now we know the contents
+ * of it.  Under --strict, this buffers structured objects in-core,
+ * to be checked at the end.
+ */
+static void write_object(unsigned nr, enum object_type type,
+			 void *buf, unsigned long size)
+{
+	if (!strict) {
+		if (write_sha1_file(buf, size, typename(type), obj_list[nr].sha1) < 0)
+			die("failed to write object");
+		added_object(nr, type, buf, size);
+		free(buf);
+		obj_list[nr].obj = NULL;
+	} else if (type == OBJ_BLOB) {
+		struct blob *blob;
+		if (write_sha1_file(buf, size, typename(type), obj_list[nr].sha1) < 0)
+			die("failed to write object");
+		added_object(nr, type, buf, size);
+		free(buf);
+
+		blob = lookup_blob(obj_list[nr].sha1);
+		if (blob)
+			blob->object.flags |= FLAG_WRITTEN;
+		else
+			die("invalid blob object");
+		obj_list[nr].obj = NULL;
+	} else {
+		struct object *obj;
+		int eaten;
+		hash_sha1_file(buf, size, typename(type), obj_list[nr].sha1);
+		added_object(nr, type, buf, size);
+		obj = parse_object_buffer(obj_list[nr].sha1, type, size, buf, &eaten);
+		if (!obj)
+			die("invalid %s", typename(type));
+		add_object_buffer(obj, buf, size);
+		obj->flags |= FLAG_OPEN;
+		obj_list[nr].obj = obj;
+	}
+}
+
+static void resolve_delta(unsigned nr, enum object_type type,
+			  void *base, unsigned long base_size,
+			  void *delta, unsigned long delta_size)
+{
+	void *result;
+	unsigned long result_size;
+
+	result = patch_delta(base, base_size,
+			     delta, delta_size,
+			     &result_size);
+	if (!result)
+		die("failed to apply delta");
+	free(delta);
+	write_object(nr, type, result, result_size);
+}
+
+/*
+ * We now know the contents of an object (which is nr-th in the pack);
+ * resolve all the deltified objects that are based on it.
+ */
+static void added_object(unsigned nr, enum object_type type,
+			 void *data, unsigned long size)
+{
+	struct delta_info **p = &delta_list;
+	struct delta_info *info;
+
+	while ((info = *p) != NULL) {
+		if (!hashcmp(info->base_sha1, obj_list[nr].sha1) ||
+		    info->base_offset == obj_list[nr].offset) {
+			*p = info->next;
+			p = &delta_list;
+			resolve_delta(info->nr, type, data, size,
+				      info->delta, info->size);
+			free(info);
+			continue;
+		}
+		p = &info->next;
+	}
+}
+
+static void unpack_non_delta_entry(enum object_type type, unsigned long size,
+				   unsigned nr)
+{
+	void *buf = get_data(size);
+
+	if (!dry_run && buf)
+		write_object(nr, type, buf, size);
+	else
+		free(buf);
+}
+
+static int resolve_against_held(unsigned nr, const unsigned char *base,
+				void *delta_data, unsigned long delta_size)
+{
+	struct object *obj;
+	struct obj_buffer *obj_buffer;
+	obj = lookup_object(base);
+	if (!obj)
+		return 0;
+	obj_buffer = lookup_object_buffer(obj);
+	if (!obj_buffer)
+		return 0;
+	resolve_delta(nr, obj->type, obj_buffer->buffer,
+		      obj_buffer->size, delta_data, delta_size);
+	return 1;
+}
+
+static void unpack_delta_entry(enum object_type type, unsigned long delta_size,
+			       unsigned nr)
+{
+	void *delta_data, *base;
+	unsigned long base_size;
+	unsigned char base_sha1[20];
+
+	if (type == OBJ_REF_DELTA) {
+		hashcpy(base_sha1, fill(20));
+		use(20);
+		delta_data = get_data(delta_size);
+		if (dry_run || !delta_data) {
+			free(delta_data);
+			return;
+		}
+		if (has_sha1_file(base_sha1))
+			; /* Ok we have this one */
+		else if (resolve_against_held(nr, base_sha1,
+					      delta_data, delta_size))
+			return; /* we are done */
+		else {
+			/* cannot resolve yet --- queue it */
+			hashcpy(obj_list[nr].sha1, null_sha1);
+			add_delta_to_list(nr, base_sha1, 0, delta_data, delta_size);
+			return;
+		}
+	} else {
+		unsigned base_found = 0;
+		unsigned char *pack, c;
+		off_t base_offset;
+		unsigned lo, mid, hi;
+
+		pack = fill(1);
+		c = *pack;
+		use(1);
+		base_offset = c & 127;
+		while (c & 128) {
+			base_offset += 1;
+			if (!base_offset || MSB(base_offset, 7))
+				die("offset value overflow for delta base object");
+			pack = fill(1);
+			c = *pack;
+			use(1);
+			base_offset = (base_offset << 7) + (c & 127);
+		}
+		base_offset = obj_list[nr].offset - base_offset;
+		if (base_offset <= 0 || base_offset >= obj_list[nr].offset)
+			die("offset value out of bound for delta base object");
+
+		delta_data = get_data(delta_size);
+		if (dry_run || !delta_data) {
+			free(delta_data);
+			return;
+		}
+		lo = 0;
+		hi = nr;
+		while (lo < hi) {
+			mid = (lo + hi)/2;
+			if (base_offset < obj_list[mid].offset) {
+				hi = mid;
+			} else if (base_offset > obj_list[mid].offset) {
+				lo = mid + 1;
+			} else {
+				hashcpy(base_sha1, obj_list[mid].sha1);
+				base_found = !is_null_sha1(base_sha1);
+				break;
+			}
+		}
+		if (!base_found) {
+			/*
+			 * The delta base object is itself a delta that
+			 * has not been resolved yet.
+			 */
+			hashcpy(obj_list[nr].sha1, null_sha1);
+			add_delta_to_list(nr, null_sha1, base_offset, delta_data, delta_size);
+			return;
+		}
+	}
+
+	if (resolve_against_held(nr, base_sha1, delta_data, delta_size))
+		return;
+
+	base = read_sha1_file(base_sha1, &type, &base_size);
+	if (!base) {
+		error("failed to read delta-pack base object %s",
+		      sha1_to_hex(base_sha1));
+		if (!recover)
+			exit(1);
+		has_errors = 1;
+		return;
+	}
+	resolve_delta(nr, type, base, base_size, delta_data, delta_size);
+	free(base);
+}
+
+static void unpack_one(unsigned nr)
+{
+	unsigned shift;
+	unsigned char *pack;
+	unsigned long size, c;
+	enum object_type type;
+
+	obj_list[nr].offset = consumed_bytes;
+
+	pack = fill(1);
+	c = *pack;
+	use(1);
+	type = (c >> 4) & 7;
+	size = (c & 15);
+	shift = 4;
+	while (c & 0x80) {
+		pack = fill(1);
+		c = *pack;
+		use(1);
+		size += (c & 0x7f) << shift;
+		shift += 7;
+	}
+
+	switch (type) {
+	case OBJ_COMMIT:
+	case OBJ_TREE:
+	case OBJ_BLOB:
+	case OBJ_TAG:
+		unpack_non_delta_entry(type, size, nr);
+		return;
+	case OBJ_REF_DELTA:
+	case OBJ_OFS_DELTA:
+		unpack_delta_entry(type, size, nr);
+		return;
+	default:
+		error("bad object type %d", type);
+		has_errors = 1;
+		if (recover)
+			return;
+		exit(1);
+	}
+}
+
+static void unpack_all(void)
+{
+	int i;
+	struct progress *progress = NULL;
+	struct pack_header *hdr = fill(sizeof(struct pack_header));
+
+	nr_objects = ntohl(hdr->hdr_entries);
+
+	if (ntohl(hdr->hdr_signature) != PACK_SIGNATURE)
+		die("bad pack file");
+	if (!pack_version_ok(hdr->hdr_version))
+		die("unknown pack file version %"PRIu32,
+			ntohl(hdr->hdr_version));
+	use(sizeof(struct pack_header));
+
+	if (!quiet)
+		progress = start_progress("Unpacking objects", nr_objects);
+	obj_list = xcalloc(nr_objects, sizeof(*obj_list));
+	for (i = 0; i < nr_objects; i++) {
+		unpack_one(i);
+		display_progress(progress, i + 1);
+	}
+	stop_progress(&progress);
+
+	if (delta_list)
+		die("unresolved deltas left after unpacking");
+}
+
+int cmd_unpack_objects(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	unsigned char sha1[20];
+
+	read_replace_refs = 0;
+
+	git_config(git_default_config, NULL);
+
+	quiet = !isatty(2);
+
+	for (i = 1 ; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (*arg == '-') {
+			if (!strcmp(arg, "-n")) {
+				dry_run = 1;
+				continue;
+			}
+			if (!strcmp(arg, "-q")) {
+				quiet = 1;
+				continue;
+			}
+			if (!strcmp(arg, "-r")) {
+				recover = 1;
+				continue;
+			}
+			if (!strcmp(arg, "--strict")) {
+				strict = 1;
+				continue;
+			}
+			if (!prefixcmp(arg, "--pack_header=")) {
+				struct pack_header *hdr;
+				char *c;
+
+				hdr = (struct pack_header *)buffer;
+				hdr->hdr_signature = htonl(PACK_SIGNATURE);
+				hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
+				if (*c != ',')
+					die("bad %s", arg);
+				hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
+				if (*c)
+					die("bad %s", arg);
+				len = sizeof(*hdr);
+				continue;
+			}
+			usage(unpack_usage);
+		}
+
+		/* We don't take any non-flag arguments now.. Maybe some day */
+		usage(unpack_usage);
+	}
+	git_SHA1_Init(&ctx);
+	unpack_all();
+	git_SHA1_Update(&ctx, buffer, offset);
+	git_SHA1_Final(sha1, &ctx);
+	if (strict)
+		write_rest();
+	if (hashcmp(fill(20), sha1))
+		die("final sha1 did not match");
+	use(20);
+
+	/* Write the last part of the buffer to stdout */
+	while (len) {
+		int ret = xwrite(1, buffer + offset, len);
+		if (ret <= 0)
+			break;
+		len -= ret;
+		offset += ret;
+	}
+
+	/* All done */
+	return has_errors;
+}
diff --git a/builtin/update-index.c b/builtin/update-index.c
new file mode 100644
index 0000000..3ab214d
--- /dev/null
+++ b/builtin/update-index.c
@@ -0,0 +1,788 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "quote.h"
+#include "cache-tree.h"
+#include "tree-walk.h"
+#include "builtin.h"
+#include "refs.h"
+#include "resolve-undo.h"
+
+/*
+ * Default to not allowing changes to the list of files. The
+ * tool doesn't actually care, but this makes it harder to add
+ * files to the revision control by mistake by doing something
+ * like "git update-index *" and suddenly having all the object
+ * files be revision controlled.
+ */
+static int allow_add;
+static int allow_remove;
+static int allow_replace;
+static int info_only;
+static int force_remove;
+static int verbose;
+static int mark_valid_only;
+static int mark_skip_worktree_only;
+#define MARK_FLAG 1
+#define UNMARK_FLAG 2
+
+__attribute__((format (printf, 1, 2)))
+static void report(const char *fmt, ...)
+{
+	va_list vp;
+
+	if (!verbose)
+		return;
+
+	va_start(vp, fmt);
+	vprintf(fmt, vp);
+	putchar('\n');
+	va_end(vp);
+}
+
+static int mark_ce_flags(const char *path, int flag, int mark)
+{
+	int namelen = strlen(path);
+	int pos = cache_name_pos(path, namelen);
+	if (0 <= pos) {
+		if (mark)
+			active_cache[pos]->ce_flags |= flag;
+		else
+			active_cache[pos]->ce_flags &= ~flag;
+		cache_tree_invalidate_path(active_cache_tree, path);
+		active_cache_changed = 1;
+		return 0;
+	}
+	return -1;
+}
+
+static int remove_one_path(const char *path)
+{
+	if (!allow_remove)
+		return error("%s: does not exist and --remove not passed", path);
+	if (remove_file_from_cache(path))
+		return error("%s: cannot remove from the index", path);
+	return 0;
+}
+
+/*
+ * Handle a path that couldn't be lstat'ed. It's either:
+ *  - missing file (ENOENT or ENOTDIR). That's ok if we're
+ *    supposed to be removing it and the removal actually
+ *    succeeds.
+ *  - permission error. That's never ok.
+ */
+static int process_lstat_error(const char *path, int err)
+{
+	if (err == ENOENT || err == ENOTDIR)
+		return remove_one_path(path);
+	return error("lstat(\"%s\"): %s", path, strerror(errno));
+}
+
+static int add_one_path(struct cache_entry *old, const char *path, int len, struct stat *st)
+{
+	int option, size;
+	struct cache_entry *ce;
+
+	/* Was the old index entry already up-to-date? */
+	if (old && !ce_stage(old) && !ce_match_stat(old, st, 0))
+		return 0;
+
+	size = cache_entry_size(len);
+	ce = xcalloc(1, size);
+	memcpy(ce->name, path, len);
+	ce->ce_flags = len;
+	fill_stat_cache_info(ce, st);
+	ce->ce_mode = ce_mode_from_stat(old, st->st_mode);
+
+	if (index_path(ce->sha1, path, st, !info_only))
+		return -1;
+	option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
+	option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
+	if (add_cache_entry(ce, option))
+		return error("%s: cannot add to the index - missing --add option?", path);
+	return 0;
+}
+
+/*
+ * Handle a path that was a directory. Four cases:
+ *
+ *  - it's already a gitlink in the index, and we keep it that
+ *    way, and update it if we can (if we cannot find the HEAD,
+ *    we're going to keep it unchanged in the index!)
+ *
+ *  - it's a *file* in the index, in which case it should be
+ *    removed as a file if removal is allowed, since it doesn't
+ *    exist as such any more. If removal isn't allowed, it's
+ *    an error.
+ *
+ *    (NOTE! This is old and arguably fairly strange behaviour.
+ *    We might want to make this an error unconditionally, and
+ *    use "--force-remove" if you actually want to force removal).
+ *
+ *  - it used to exist as a subdirectory (ie multiple files with
+ *    this particular prefix) in the index, in which case it's wrong
+ *    to try to update it as a directory.
+ *
+ *  - it doesn't exist at all in the index, but it is a valid
+ *    git directory, and it should be *added* as a gitlink.
+ */
+static int process_directory(const char *path, int len, struct stat *st)
+{
+	unsigned char sha1[20];
+	int pos = cache_name_pos(path, len);
+
+	/* Exact match: file or existing gitlink */
+	if (pos >= 0) {
+		struct cache_entry *ce = active_cache[pos];
+		if (S_ISGITLINK(ce->ce_mode)) {
+
+			/* Do nothing to the index if there is no HEAD! */
+			if (resolve_gitlink_ref(path, "HEAD", sha1) < 0)
+				return 0;
+
+			return add_one_path(ce, path, len, st);
+		}
+		/* Should this be an unconditional error? */
+		return remove_one_path(path);
+	}
+
+	/* Inexact match: is there perhaps a subdirectory match? */
+	pos = -pos-1;
+	while (pos < active_nr) {
+		struct cache_entry *ce = active_cache[pos++];
+
+		if (strncmp(ce->name, path, len))
+			break;
+		if (ce->name[len] > '/')
+			break;
+		if (ce->name[len] < '/')
+			continue;
+
+		/* Subdirectory match - error out */
+		return error("%s: is a directory - add individual files instead", path);
+	}
+
+	/* No match - should we add it as a gitlink? */
+	if (!resolve_gitlink_ref(path, "HEAD", sha1))
+		return add_one_path(NULL, path, len, st);
+
+	/* Error out. */
+	return error("%s: is a directory - add files inside instead", path);
+}
+
+static int process_path(const char *path)
+{
+	int pos, len;
+	struct stat st;
+	struct cache_entry *ce;
+
+	len = strlen(path);
+	if (has_symlink_leading_path(path, len))
+		return error("'%s' is beyond a symbolic link", path);
+
+	pos = cache_name_pos(path, len);
+	ce = pos < 0 ? NULL : active_cache[pos];
+	if (ce && ce_skip_worktree(ce)) {
+		/*
+		 * working directory version is assumed "good"
+		 * so updating it does not make sense.
+		 * On the other hand, removing it from index should work
+		 */
+		if (allow_remove && remove_file_from_cache(path))
+			return error("%s: cannot remove from the index", path);
+		return 0;
+	}
+
+	/*
+	 * First things first: get the stat information, to decide
+	 * what to do about the pathname!
+	 */
+	if (lstat(path, &st) < 0)
+		return process_lstat_error(path, errno);
+
+	if (S_ISDIR(st.st_mode))
+		return process_directory(path, len, &st);
+
+	/*
+	 * Process a regular file
+	 */
+	if (ce && S_ISGITLINK(ce->ce_mode))
+		return error("%s is already a gitlink, not replacing", path);
+
+	return add_one_path(ce, path, len, &st);
+}
+
+static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
+			 const char *path, int stage)
+{
+	int size, len, option;
+	struct cache_entry *ce;
+
+	if (!verify_path(path))
+		return error("Invalid path '%s'", path);
+
+	len = strlen(path);
+	size = cache_entry_size(len);
+	ce = xcalloc(1, size);
+
+	hashcpy(ce->sha1, sha1);
+	memcpy(ce->name, path, len);
+	ce->ce_flags = create_ce_flags(len, stage);
+	ce->ce_mode = create_ce_mode(mode);
+	if (assume_unchanged)
+		ce->ce_flags |= CE_VALID;
+	option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
+	option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
+	if (add_cache_entry(ce, option))
+		return error("%s: cannot add to the index - missing --add option?",
+			     path);
+	report("add '%s'", path);
+	return 0;
+}
+
+static void chmod_path(int flip, const char *path)
+{
+	int pos;
+	struct cache_entry *ce;
+	unsigned int mode;
+
+	pos = cache_name_pos(path, strlen(path));
+	if (pos < 0)
+		goto fail;
+	ce = active_cache[pos];
+	mode = ce->ce_mode;
+	if (!S_ISREG(mode))
+		goto fail;
+	switch (flip) {
+	case '+':
+		ce->ce_mode |= 0111; break;
+	case '-':
+		ce->ce_mode &= ~0111; break;
+	default:
+		goto fail;
+	}
+	cache_tree_invalidate_path(active_cache_tree, path);
+	active_cache_changed = 1;
+	report("chmod %cx '%s'", flip, path);
+	return;
+ fail:
+	die("git update-index: cannot chmod %cx '%s'", flip, path);
+}
+
+static void update_one(const char *path, const char *prefix, int prefix_length)
+{
+	const char *p = prefix_path(prefix, prefix_length, path);
+	if (!verify_path(p)) {
+		fprintf(stderr, "Ignoring path %s\n", path);
+		goto free_return;
+	}
+	if (mark_valid_only) {
+		if (mark_ce_flags(p, CE_VALID, mark_valid_only == MARK_FLAG))
+			die("Unable to mark file %s", path);
+		goto free_return;
+	}
+	if (mark_skip_worktree_only) {
+		if (mark_ce_flags(p, CE_SKIP_WORKTREE, mark_skip_worktree_only == MARK_FLAG))
+			die("Unable to mark file %s", path);
+		goto free_return;
+	}
+
+	if (force_remove) {
+		if (remove_file_from_cache(p))
+			die("git update-index: unable to remove %s", path);
+		report("remove '%s'", path);
+		goto free_return;
+	}
+	if (process_path(p))
+		die("Unable to process path %s", path);
+	report("add '%s'", path);
+ free_return:
+	if (p < path || p > path + strlen(path))
+		free((char *)p);
+}
+
+static void read_index_info(int line_termination)
+{
+	struct strbuf buf = STRBUF_INIT;
+	struct strbuf uq = STRBUF_INIT;
+
+	while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
+		char *ptr, *tab;
+		char *path_name;
+		unsigned char sha1[20];
+		unsigned int mode;
+		unsigned long ul;
+		int stage;
+
+		/* This reads lines formatted in one of three formats:
+		 *
+		 * (1) mode         SP sha1          TAB path
+		 * The first format is what "git apply --index-info"
+		 * reports, and used to reconstruct a partial tree
+		 * that is used for phony merge base tree when falling
+		 * back on 3-way merge.
+		 *
+		 * (2) mode SP type SP sha1          TAB path
+		 * The second format is to stuff "git ls-tree" output
+		 * into the index file.
+		 *
+		 * (3) mode         SP sha1 SP stage TAB path
+		 * This format is to put higher order stages into the
+		 * index file and matches "git ls-files --stage" output.
+		 */
+		errno = 0;
+		ul = strtoul(buf.buf, &ptr, 8);
+		if (ptr == buf.buf || *ptr != ' '
+		    || errno || (unsigned int) ul != ul)
+			goto bad_line;
+		mode = ul;
+
+		tab = strchr(ptr, '\t');
+		if (!tab || tab - ptr < 41)
+			goto bad_line;
+
+		if (tab[-2] == ' ' && '0' <= tab[-1] && tab[-1] <= '3') {
+			stage = tab[-1] - '0';
+			ptr = tab + 1; /* point at the head of path */
+			tab = tab - 2; /* point at tail of sha1 */
+		}
+		else {
+			stage = 0;
+			ptr = tab + 1; /* point at the head of path */
+		}
+
+		if (get_sha1_hex(tab - 40, sha1) || tab[-41] != ' ')
+			goto bad_line;
+
+		path_name = ptr;
+		if (line_termination && path_name[0] == '"') {
+			strbuf_reset(&uq);
+			if (unquote_c_style(&uq, path_name, NULL)) {
+				die("git update-index: bad quoting of path name");
+			}
+			path_name = uq.buf;
+		}
+
+		if (!verify_path(path_name)) {
+			fprintf(stderr, "Ignoring path %s\n", path_name);
+			continue;
+		}
+
+		if (!mode) {
+			/* mode == 0 means there is no such path -- remove */
+			if (remove_file_from_cache(path_name))
+				die("git update-index: unable to remove %s",
+				    ptr);
+		}
+		else {
+			/* mode ' ' sha1 '\t' name
+			 * ptr[-1] points at tab,
+			 * ptr[-41] is at the beginning of sha1
+			 */
+			ptr[-42] = ptr[-1] = 0;
+			if (add_cacheinfo(mode, sha1, path_name, stage))
+				die("git update-index: unable to update %s",
+				    path_name);
+		}
+		continue;
+
+	bad_line:
+		die("malformed index info %s", buf.buf);
+	}
+	strbuf_release(&buf);
+	strbuf_release(&uq);
+}
+
+static const char update_index_usage[] =
+"git update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--really-refresh] [--cacheinfo] [--chmod=(+|-)x] [--assume-unchanged] [--skip-worktree|--no-skip-worktree] [--info-only] [--force-remove] [--stdin] [--index-info] [--unresolve] [--again | -g] [--ignore-missing] [-z] [--verbose] [--] <file>...";
+
+static unsigned char head_sha1[20];
+static unsigned char merge_head_sha1[20];
+
+static struct cache_entry *read_one_ent(const char *which,
+					unsigned char *ent, const char *path,
+					int namelen, int stage)
+{
+	unsigned mode;
+	unsigned char sha1[20];
+	int size;
+	struct cache_entry *ce;
+
+	if (get_tree_entry(ent, path, sha1, &mode)) {
+		if (which)
+			error("%s: not in %s branch.", path, which);
+		return NULL;
+	}
+	if (mode == S_IFDIR) {
+		if (which)
+			error("%s: not a blob in %s branch.", path, which);
+		return NULL;
+	}
+	size = cache_entry_size(namelen);
+	ce = xcalloc(1, size);
+
+	hashcpy(ce->sha1, sha1);
+	memcpy(ce->name, path, namelen);
+	ce->ce_flags = create_ce_flags(namelen, stage);
+	ce->ce_mode = create_ce_mode(mode);
+	return ce;
+}
+
+static int unresolve_one(const char *path)
+{
+	int namelen = strlen(path);
+	int pos;
+	int ret = 0;
+	struct cache_entry *ce_2 = NULL, *ce_3 = NULL;
+
+	/* See if there is such entry in the index. */
+	pos = cache_name_pos(path, namelen);
+	if (0 <= pos) {
+		/* already merged */
+		pos = unmerge_cache_entry_at(pos);
+		if (pos < active_nr) {
+			struct cache_entry *ce = active_cache[pos];
+			if (ce_stage(ce) &&
+			    ce_namelen(ce) == namelen &&
+			    !memcmp(ce->name, path, namelen))
+				return 0;
+		}
+		/* no resolve-undo information; fall back */
+	} else {
+		/* If there isn't, either it is unmerged, or
+		 * resolved as "removed" by mistake.  We do not
+		 * want to do anything in the former case.
+		 */
+		pos = -pos-1;
+		if (pos < active_nr) {
+			struct cache_entry *ce = active_cache[pos];
+			if (ce_namelen(ce) == namelen &&
+			    !memcmp(ce->name, path, namelen)) {
+				fprintf(stderr,
+					"%s: skipping still unmerged path.\n",
+					path);
+				goto free_return;
+			}
+		}
+	}
+
+	/* Grab blobs from given path from HEAD and MERGE_HEAD,
+	 * stuff HEAD version in stage #2,
+	 * stuff MERGE_HEAD version in stage #3.
+	 */
+	ce_2 = read_one_ent("our", head_sha1, path, namelen, 2);
+	ce_3 = read_one_ent("their", merge_head_sha1, path, namelen, 3);
+
+	if (!ce_2 || !ce_3) {
+		ret = -1;
+		goto free_return;
+	}
+	if (!hashcmp(ce_2->sha1, ce_3->sha1) &&
+	    ce_2->ce_mode == ce_3->ce_mode) {
+		fprintf(stderr, "%s: identical in both, skipping.\n",
+			path);
+		goto free_return;
+	}
+
+	remove_file_from_cache(path);
+	if (add_cache_entry(ce_2, ADD_CACHE_OK_TO_ADD)) {
+		error("%s: cannot add our version to the index.", path);
+		ret = -1;
+		goto free_return;
+	}
+	if (!add_cache_entry(ce_3, ADD_CACHE_OK_TO_ADD))
+		return 0;
+	error("%s: cannot add their version to the index.", path);
+	ret = -1;
+ free_return:
+	free(ce_2);
+	free(ce_3);
+	return ret;
+}
+
+static void read_head_pointers(void)
+{
+	if (read_ref("HEAD", head_sha1))
+		die("No HEAD -- no initial commit yet?");
+	if (read_ref("MERGE_HEAD", merge_head_sha1)) {
+		fprintf(stderr, "Not in the middle of a merge.\n");
+		exit(0);
+	}
+}
+
+static int do_unresolve(int ac, const char **av,
+			const char *prefix, int prefix_length)
+{
+	int i;
+	int err = 0;
+
+	/* Read HEAD and MERGE_HEAD; if MERGE_HEAD does not exist, we
+	 * are not doing a merge, so exit with success status.
+	 */
+	read_head_pointers();
+
+	for (i = 1; i < ac; i++) {
+		const char *arg = av[i];
+		const char *p = prefix_path(prefix, prefix_length, arg);
+		err |= unresolve_one(p);
+		if (p < arg || p > arg + strlen(arg))
+			free((char *)p);
+	}
+	return err;
+}
+
+static int do_reupdate(int ac, const char **av,
+		       const char *prefix, int prefix_length)
+{
+	/* Read HEAD and run update-index on paths that are
+	 * merged and already different between index and HEAD.
+	 */
+	int pos;
+	int has_head = 1;
+	const char **pathspec = get_pathspec(prefix, av + 1);
+
+	if (read_ref("HEAD", head_sha1))
+		/* If there is no HEAD, that means it is an initial
+		 * commit.  Update everything in the index.
+		 */
+		has_head = 0;
+ redo:
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+		struct cache_entry *old = NULL;
+		int save_nr;
+
+		if (ce_stage(ce) || !ce_path_match(ce, pathspec))
+			continue;
+		if (has_head)
+			old = read_one_ent(NULL, head_sha1,
+					   ce->name, ce_namelen(ce), 0);
+		if (old && ce->ce_mode == old->ce_mode &&
+		    !hashcmp(ce->sha1, old->sha1)) {
+			free(old);
+			continue; /* unchanged */
+		}
+		/* Be careful.  The working tree may not have the
+		 * path anymore, in which case, under 'allow_remove',
+		 * or worse yet 'allow_replace', active_nr may decrease.
+		 */
+		save_nr = active_nr;
+		update_one(ce->name + prefix_length, prefix, prefix_length);
+		if (save_nr != active_nr)
+			goto redo;
+	}
+	return 0;
+}
+
+int cmd_update_index(int argc, const char **argv, const char *prefix)
+{
+	int i, newfd, entries, has_errors = 0, line_termination = '\n';
+	int allow_options = 1;
+	int read_from_stdin = 0;
+	int prefix_length = prefix ? strlen(prefix) : 0;
+	char set_executable_bit = 0;
+	unsigned int refresh_flags = 0;
+	int lock_error = 0;
+	struct lock_file *lock_file;
+
+	git_config(git_default_config, NULL);
+
+	/* We can't free this memory, it becomes part of a linked list parsed atexit() */
+	lock_file = xcalloc(1, sizeof(struct lock_file));
+
+	newfd = hold_locked_index(lock_file, 0);
+	if (newfd < 0)
+		lock_error = errno;
+
+	entries = read_cache();
+	if (entries < 0)
+		die("cache corrupted");
+
+	for (i = 1 ; i < argc; i++) {
+		const char *path = argv[i];
+		const char *p;
+
+		if (allow_options && *path == '-') {
+			if (!strcmp(path, "--")) {
+				allow_options = 0;
+				continue;
+			}
+			if (!strcmp(path, "-q")) {
+				refresh_flags |= REFRESH_QUIET;
+				continue;
+			}
+			if (!strcmp(path, "--ignore-submodules")) {
+				refresh_flags |= REFRESH_IGNORE_SUBMODULES;
+				continue;
+			}
+			if (!strcmp(path, "--add")) {
+				allow_add = 1;
+				continue;
+			}
+			if (!strcmp(path, "--replace")) {
+				allow_replace = 1;
+				continue;
+			}
+			if (!strcmp(path, "--remove")) {
+				allow_remove = 1;
+				continue;
+			}
+			if (!strcmp(path, "--unmerged")) {
+				refresh_flags |= REFRESH_UNMERGED;
+				continue;
+			}
+			if (!strcmp(path, "--refresh")) {
+				setup_work_tree();
+				has_errors |= refresh_cache(refresh_flags);
+				continue;
+			}
+			if (!strcmp(path, "--really-refresh")) {
+				setup_work_tree();
+				has_errors |= refresh_cache(REFRESH_REALLY | refresh_flags);
+				continue;
+			}
+			if (!strcmp(path, "--cacheinfo")) {
+				unsigned char sha1[20];
+				unsigned int mode;
+
+				if (i+3 >= argc)
+					die("git update-index: --cacheinfo <mode> <sha1> <path>");
+
+				if (strtoul_ui(argv[i+1], 8, &mode) ||
+				    get_sha1_hex(argv[i+2], sha1) ||
+				    add_cacheinfo(mode, sha1, argv[i+3], 0))
+					die("git update-index: --cacheinfo"
+					    " cannot add %s", argv[i+3]);
+				i += 3;
+				continue;
+			}
+			if (!strcmp(path, "--chmod=-x") ||
+			    !strcmp(path, "--chmod=+x")) {
+				if (argc <= i+1)
+					die("git update-index: %s <path>", path);
+				set_executable_bit = path[8];
+				continue;
+			}
+			if (!strcmp(path, "--assume-unchanged")) {
+				mark_valid_only = MARK_FLAG;
+				continue;
+			}
+			if (!strcmp(path, "--no-assume-unchanged")) {
+				mark_valid_only = UNMARK_FLAG;
+				continue;
+			}
+			if (!strcmp(path, "--no-skip-worktree")) {
+				mark_skip_worktree_only = UNMARK_FLAG;
+				continue;
+			}
+			if (!strcmp(path, "--skip-worktree")) {
+				mark_skip_worktree_only = MARK_FLAG;
+				continue;
+			}
+			if (!strcmp(path, "--info-only")) {
+				info_only = 1;
+				continue;
+			}
+			if (!strcmp(path, "--force-remove")) {
+				force_remove = 1;
+				continue;
+			}
+			if (!strcmp(path, "-z")) {
+				line_termination = 0;
+				continue;
+			}
+			if (!strcmp(path, "--stdin")) {
+				if (i != argc - 1)
+					die("--stdin must be at the end");
+				read_from_stdin = 1;
+				break;
+			}
+			if (!strcmp(path, "--index-info")) {
+				if (i != argc - 1)
+					die("--index-info must be at the end");
+				allow_add = allow_replace = allow_remove = 1;
+				read_index_info(line_termination);
+				break;
+			}
+			if (!strcmp(path, "--unresolve")) {
+				has_errors = do_unresolve(argc - i, argv + i,
+							  prefix, prefix_length);
+				if (has_errors)
+					active_cache_changed = 0;
+				goto finish;
+			}
+			if (!strcmp(path, "--again") || !strcmp(path, "-g")) {
+				setup_work_tree();
+				has_errors = do_reupdate(argc - i, argv + i,
+							 prefix, prefix_length);
+				if (has_errors)
+					active_cache_changed = 0;
+				goto finish;
+			}
+			if (!strcmp(path, "--ignore-missing")) {
+				refresh_flags |= REFRESH_IGNORE_MISSING;
+				continue;
+			}
+			if (!strcmp(path, "--verbose")) {
+				verbose = 1;
+				continue;
+			}
+			if (!strcmp(path, "--clear-resolve-undo")) {
+				resolve_undo_clear();
+				continue;
+			}
+			if (!strcmp(path, "-h") || !strcmp(path, "--help"))
+				usage(update_index_usage);
+			die("unknown option %s", path);
+		}
+		setup_work_tree();
+		p = prefix_path(prefix, prefix_length, path);
+		update_one(p, NULL, 0);
+		if (set_executable_bit)
+			chmod_path(set_executable_bit, p);
+		if (p < path || p > path + strlen(path))
+			free((char *)p);
+	}
+	if (read_from_stdin) {
+		struct strbuf buf = STRBUF_INIT, nbuf = STRBUF_INIT;
+
+		setup_work_tree();
+		while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
+			const char *p;
+			if (line_termination && buf.buf[0] == '"') {
+				strbuf_reset(&nbuf);
+				if (unquote_c_style(&nbuf, buf.buf, NULL))
+					die("line is badly quoted");
+				strbuf_swap(&buf, &nbuf);
+			}
+			p = prefix_path(prefix, prefix_length, buf.buf);
+			update_one(p, NULL, 0);
+			if (set_executable_bit)
+				chmod_path(set_executable_bit, p);
+			if (p < buf.buf || p > buf.buf + buf.len)
+				free((char *)p);
+		}
+		strbuf_release(&nbuf);
+		strbuf_release(&buf);
+	}
+
+ finish:
+	if (active_cache_changed) {
+		if (newfd < 0) {
+			if (refresh_flags & REFRESH_QUIET)
+				exit(128);
+			unable_to_lock_index_die(get_index_file(), lock_error);
+		}
+		if (write_cache(newfd, active_cache, active_nr) ||
+		    commit_locked_index(lock_file))
+			die("Unable to write new index file");
+	}
+
+	rollback_lock_file(lock_file);
+
+	return has_errors ? 1 : 0;
+}
diff --git a/builtin/update-ref.c b/builtin/update-ref.c
new file mode 100644
index 0000000..76ba1d5
--- /dev/null
+++ b/builtin/update-ref.c
@@ -0,0 +1,58 @@
+#include "cache.h"
+#include "refs.h"
+#include "builtin.h"
+#include "parse-options.h"
+
+static const char * const git_update_ref_usage[] = {
+	"git update-ref [options] -d <refname> [<oldval>]",
+	"git update-ref [options]    <refname> <newval> [<oldval>]",
+	NULL
+};
+
+int cmd_update_ref(int argc, const char **argv, const char *prefix)
+{
+	const char *refname, *oldval, *msg=NULL;
+	unsigned char sha1[20], oldsha1[20];
+	int delete = 0, no_deref = 0, flags = 0;
+	struct option options[] = {
+		OPT_STRING( 'm', NULL, &msg, "reason", "reason of the update"),
+		OPT_BOOLEAN('d', NULL, &delete, "deletes the reference"),
+		OPT_BOOLEAN( 0 , "no-deref", &no_deref,
+					"update <refname> not the one it points to"),
+		OPT_END(),
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, prefix, options, git_update_ref_usage,
+			     0);
+	if (msg && !*msg)
+		die("Refusing to perform update with empty message.");
+
+	if (delete) {
+		if (argc < 1 || argc > 2)
+			usage_with_options(git_update_ref_usage, options);
+		refname = argv[0];
+		oldval = argv[1];
+	} else {
+		const char *value;
+		if (argc < 2 || argc > 3)
+			usage_with_options(git_update_ref_usage, options);
+		refname = argv[0];
+		value = argv[1];
+		oldval = argv[2];
+		if (get_sha1(value, sha1))
+			die("%s: not a valid SHA1", value);
+	}
+
+	hashclr(oldsha1); /* all-zero hash in case oldval is the empty string */
+	if (oldval && *oldval && get_sha1(oldval, oldsha1))
+		die("%s: not a valid old SHA1", oldval);
+
+	if (no_deref)
+		flags = REF_NODEREF;
+	if (delete)
+		return delete_ref(refname, oldval ? oldsha1 : NULL, flags);
+	else
+		return update_ref(msg, refname, sha1, oldval ? oldsha1 : NULL,
+				  flags, DIE_ON_ERR);
+}
diff --git a/builtin/update-server-info.c b/builtin/update-server-info.c
new file mode 100644
index 0000000..2b3fddc
--- /dev/null
+++ b/builtin/update-server-info.c
@@ -0,0 +1,25 @@
+#include "cache.h"
+#include "builtin.h"
+#include "parse-options.h"
+
+static const char * const update_server_info_usage[] = {
+	"git update-server-info [--force]",
+	NULL
+};
+
+int cmd_update_server_info(int argc, const char **argv, const char *prefix)
+{
+	int force = 0;
+	struct option options[] = {
+		OPT_BOOLEAN('f', "force", &force,
+			"update the info files from scratch"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, options,
+			     update_server_info_usage, 0);
+	if (argc > 0)
+		usage_with_options(update_server_info_usage, options);
+
+	return !!update_server_info(force);
+}
diff --git a/builtin/upload-archive.c b/builtin/upload-archive.c
new file mode 100644
index 0000000..73f788e
--- /dev/null
+++ b/builtin/upload-archive.c
@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) 2006 Franck Bui-Huu
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "archive.h"
+#include "pkt-line.h"
+#include "sideband.h"
+
+static const char upload_archive_usage[] =
+	"git upload-archive <repo>";
+
+static const char deadchild[] =
+"git upload-archive: archiver died with error";
+
+static const char lostchild[] =
+"git upload-archive: archiver process was lost";
+
+#define MAX_ARGS (64)
+
+static int run_upload_archive(int argc, const char **argv, const char *prefix)
+{
+	const char *sent_argv[MAX_ARGS];
+	const char *arg_cmd = "argument ";
+	char *p, buf[4096];
+	int sent_argc;
+	int len;
+
+	if (argc != 2)
+		usage(upload_archive_usage);
+
+	if (strlen(argv[1]) + 1 > sizeof(buf))
+		die("insanely long repository name");
+
+	strcpy(buf, argv[1]); /* enter-repo smudges its argument */
+
+	if (!enter_repo(buf, 0))
+		die("'%s' does not appear to be a git repository", buf);
+
+	/* put received options in sent_argv[] */
+	sent_argc = 1;
+	sent_argv[0] = "git-upload-archive";
+	for (p = buf;;) {
+		/* This will die if not enough free space in buf */
+		len = packet_read_line(0, p, (buf + sizeof buf) - p);
+		if (len == 0)
+			break;	/* got a flush */
+		if (sent_argc > MAX_ARGS - 2)
+			die("Too many options (>%d)", MAX_ARGS - 2);
+
+		if (p[len-1] == '\n') {
+			p[--len] = 0;
+		}
+		if (len < strlen(arg_cmd) ||
+		    strncmp(arg_cmd, p, strlen(arg_cmd)))
+			die("'argument' token or flush expected");
+
+		len -= strlen(arg_cmd);
+		memmove(p, p + strlen(arg_cmd), len);
+		sent_argv[sent_argc++] = p;
+		p += len;
+		*p++ = 0;
+	}
+	sent_argv[sent_argc] = NULL;
+
+	/* parse all options sent by the client */
+	return write_archive(sent_argc, sent_argv, prefix, 0);
+}
+
+__attribute__((format (printf, 1, 2)))
+static void error_clnt(const char *fmt, ...)
+{
+	char buf[1024];
+	va_list params;
+	int len;
+
+	va_start(params, fmt);
+	len = vsprintf(buf, fmt, params);
+	va_end(params);
+	send_sideband(1, 3, buf, len, LARGE_PACKET_MAX);
+	die("sent error to the client: %s", buf);
+}
+
+static ssize_t process_input(int child_fd, int band)
+{
+	char buf[16384];
+	ssize_t sz = read(child_fd, buf, sizeof(buf));
+	if (sz < 0) {
+		if (errno != EAGAIN && errno != EINTR)
+			error_clnt("read error: %s\n", strerror(errno));
+		return sz;
+	}
+	send_sideband(1, band, buf, sz, LARGE_PACKET_MAX);
+	return sz;
+}
+
+int cmd_upload_archive(int argc, const char **argv, const char *prefix)
+{
+	pid_t writer;
+	int fd1[2], fd2[2];
+	/*
+	 * Set up sideband subprocess.
+	 *
+	 * We (parent) monitor and read from child, sending its fd#1 and fd#2
+	 * multiplexed out to our fd#1.  If the child dies, we tell the other
+	 * end over channel #3.
+	 */
+	if (pipe(fd1) < 0 || pipe(fd2) < 0) {
+		int err = errno;
+		packet_write(1, "NACK pipe failed on the remote side\n");
+		die("upload-archive: %s", strerror(err));
+	}
+	writer = fork();
+	if (writer < 0) {
+		int err = errno;
+		packet_write(1, "NACK fork failed on the remote side\n");
+		die("upload-archive: %s", strerror(err));
+	}
+	if (!writer) {
+		/* child - connect fd#1 and fd#2 to the pipe */
+		dup2(fd1[1], 1);
+		dup2(fd2[1], 2);
+		close(fd1[1]); close(fd2[1]);
+		close(fd1[0]); close(fd2[0]); /* we do not read from pipe */
+
+		exit(run_upload_archive(argc, argv, prefix));
+	}
+
+	/* parent - read from child, multiplex and send out to fd#1 */
+	close(fd1[1]); close(fd2[1]); /* we do not write to pipe */
+	packet_write(1, "ACK\n");
+	packet_flush(1);
+
+	while (1) {
+		struct pollfd pfd[2];
+		int status;
+
+		pfd[0].fd = fd1[0];
+		pfd[0].events = POLLIN;
+		pfd[1].fd = fd2[0];
+		pfd[1].events = POLLIN;
+		if (poll(pfd, 2, -1) < 0) {
+			if (errno != EINTR) {
+				error("poll failed resuming: %s",
+				      strerror(errno));
+				sleep(1);
+			}
+			continue;
+		}
+		if (pfd[1].revents & POLLIN)
+			/* Status stream ready */
+			if (process_input(pfd[1].fd, 2))
+				continue;
+		if (pfd[0].revents & POLLIN)
+			/* Data stream ready */
+			if (process_input(pfd[0].fd, 1))
+				continue;
+
+		if (waitpid(writer, &status, 0) < 0)
+			error_clnt("%s", lostchild);
+		else if (!WIFEXITED(status) || WEXITSTATUS(status) > 0)
+			error_clnt("%s", deadchild);
+		packet_flush(1);
+		break;
+	}
+	return 0;
+}
diff --git a/builtin/var.c b/builtin/var.c
new file mode 100644
index 0000000..70fdb4d
--- /dev/null
+++ b/builtin/var.c
@@ -0,0 +1,99 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Eric Biederman, 2005
+ */
+#include "cache.h"
+#include "exec_cmd.h"
+
+static const char var_usage[] = "git var (-l | <variable>)";
+
+static const char *editor(int flag)
+{
+	const char *pgm = git_editor();
+
+	if (!pgm && flag & IDENT_ERROR_ON_NO_NAME)
+		die("Terminal is dumb, but EDITOR unset");
+
+	return pgm;
+}
+
+static const char *pager(int flag)
+{
+	const char *pgm = git_pager(1);
+
+	if (!pgm)
+		pgm = "cat";
+	return pgm;
+}
+
+struct git_var {
+	const char *name;
+	const char *(*read)(int);
+};
+static struct git_var git_vars[] = {
+	{ "GIT_COMMITTER_IDENT", git_committer_info },
+	{ "GIT_AUTHOR_IDENT",   git_author_info },
+	{ "GIT_EDITOR", editor },
+	{ "GIT_PAGER", pager },
+	{ "", NULL },
+};
+
+static void list_vars(void)
+{
+	struct git_var *ptr;
+	const char *val;
+
+	for (ptr = git_vars; ptr->read; ptr++)
+		if ((val = ptr->read(0)))
+			printf("%s=%s\n", ptr->name, val);
+}
+
+static const char *read_var(const char *var)
+{
+	struct git_var *ptr;
+	const char *val;
+	val = NULL;
+	for (ptr = git_vars; ptr->read; ptr++) {
+		if (strcmp(var, ptr->name) == 0) {
+			val = ptr->read(IDENT_ERROR_ON_NO_NAME);
+			break;
+		}
+	}
+	return val;
+}
+
+static int show_config(const char *var, const char *value, void *cb)
+{
+	if (value)
+		printf("%s=%s\n", var, value);
+	else
+		printf("%s\n", var);
+	return git_default_config(var, value, cb);
+}
+
+int cmd_var(int argc, const char **argv, const char *prefix)
+{
+	const char *val;
+	int nongit;
+	if (argc != 2) {
+		usage(var_usage);
+	}
+
+	setup_git_directory_gently(&nongit);
+	val = NULL;
+
+	if (strcmp(argv[1], "-l") == 0) {
+		git_config(show_config, NULL);
+		list_vars();
+		return 0;
+	}
+	git_config(git_default_config, NULL);
+	val = read_var(argv[1]);
+	if (!val)
+		usage(var_usage);
+
+	printf("%s\n", val);
+
+	return 0;
+}
diff --git a/builtin/verify-pack.c b/builtin/verify-pack.c
new file mode 100644
index 0000000..b6079ae
--- /dev/null
+++ b/builtin/verify-pack.c
@@ -0,0 +1,166 @@
+#include "builtin.h"
+#include "cache.h"
+#include "pack.h"
+#include "pack-revindex.h"
+#include "parse-options.h"
+
+#define MAX_CHAIN 50
+
+#define VERIFY_PACK_VERBOSE 01
+#define VERIFY_PACK_STAT_ONLY 02
+
+static void show_pack_info(struct packed_git *p, unsigned int flags)
+{
+	uint32_t nr_objects, i;
+	int cnt;
+	int stat_only = flags & VERIFY_PACK_STAT_ONLY;
+	unsigned long chain_histogram[MAX_CHAIN+1], baseobjects;
+
+	nr_objects = p->num_objects;
+	memset(chain_histogram, 0, sizeof(chain_histogram));
+	baseobjects = 0;
+
+	for (i = 0; i < nr_objects; i++) {
+		const unsigned char *sha1;
+		unsigned char base_sha1[20];
+		const char *type;
+		unsigned long size;
+		unsigned long store_size;
+		off_t offset;
+		unsigned int delta_chain_length;
+
+		sha1 = nth_packed_object_sha1(p, i);
+		if (!sha1)
+			die("internal error pack-check nth-packed-object");
+		offset = nth_packed_object_offset(p, i);
+		type = packed_object_info_detail(p, offset, &size, &store_size,
+						 &delta_chain_length,
+						 base_sha1);
+		if (!stat_only)
+			printf("%s ", sha1_to_hex(sha1));
+		if (!delta_chain_length) {
+			if (!stat_only)
+				printf("%-6s %lu %lu %"PRIuMAX"\n",
+				       type, size, store_size, (uintmax_t)offset);
+			baseobjects++;
+		}
+		else {
+			if (!stat_only)
+				printf("%-6s %lu %lu %"PRIuMAX" %u %s\n",
+				       type, size, store_size, (uintmax_t)offset,
+				       delta_chain_length, sha1_to_hex(base_sha1));
+			if (delta_chain_length <= MAX_CHAIN)
+				chain_histogram[delta_chain_length]++;
+			else
+				chain_histogram[0]++;
+		}
+	}
+
+	if (baseobjects)
+		printf("non delta: %lu object%s\n",
+		       baseobjects, baseobjects > 1 ? "s" : "");
+
+	for (cnt = 1; cnt <= MAX_CHAIN; cnt++) {
+		if (!chain_histogram[cnt])
+			continue;
+		printf("chain length = %d: %lu object%s\n", cnt,
+		       chain_histogram[cnt],
+		       chain_histogram[cnt] > 1 ? "s" : "");
+	}
+	if (chain_histogram[0])
+		printf("chain length > %d: %lu object%s\n", MAX_CHAIN,
+		       chain_histogram[0],
+		       chain_histogram[0] > 1 ? "s" : "");
+}
+
+static int verify_one_pack(const char *path, unsigned int flags)
+{
+	char arg[PATH_MAX];
+	int len;
+	int verbose = flags & VERIFY_PACK_VERBOSE;
+	int stat_only = flags & VERIFY_PACK_STAT_ONLY;
+	struct packed_git *pack;
+	int err;
+
+	len = strlcpy(arg, path, PATH_MAX);
+	if (len >= PATH_MAX)
+		return error("name too long: %s", path);
+
+	/*
+	 * In addition to "foo.idx" we accept "foo.pack" and "foo";
+	 * normalize these forms to "foo.idx" for add_packed_git().
+	 */
+	if (has_extension(arg, ".pack")) {
+		strcpy(arg + len - 5, ".idx");
+		len--;
+	} else if (!has_extension(arg, ".idx")) {
+		if (len + 4 >= PATH_MAX)
+			return error("name too long: %s.idx", arg);
+		strcpy(arg + len, ".idx");
+		len += 4;
+	}
+
+	/*
+	 * add_packed_git() uses our buffer (containing "foo.idx") to
+	 * build the pack filename ("foo.pack").  Make sure it fits.
+	 */
+	if (len + 1 >= PATH_MAX) {
+		arg[len - 4] = '\0';
+		return error("name too long: %s.pack", arg);
+	}
+
+	pack = add_packed_git(arg, len, 1);
+	if (!pack)
+		return error("packfile %s not found.", arg);
+
+	install_packed_git(pack);
+
+	if (!stat_only)
+		err = verify_pack(pack);
+	else
+		err = open_pack_index(pack);
+
+	if (verbose || stat_only) {
+		if (err)
+			printf("%s: bad\n", pack->pack_name);
+		else {
+			show_pack_info(pack, flags);
+			if (!stat_only)
+				printf("%s: ok\n", pack->pack_name);
+		}
+	}
+
+	return err;
+}
+
+static const char * const verify_pack_usage[] = {
+	"git verify-pack [-v|--verbose] [-s|--stat-only] <pack>...",
+	NULL
+};
+
+int cmd_verify_pack(int argc, const char **argv, const char *prefix)
+{
+	int err = 0;
+	unsigned int flags = 0;
+	int i;
+	const struct option verify_pack_options[] = {
+		OPT_BIT('v', "verbose", &flags, "verbose",
+			VERIFY_PACK_VERBOSE),
+		OPT_BIT('s', "stat-only", &flags, "show statistics only",
+			VERIFY_PACK_STAT_ONLY),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, prefix, verify_pack_options,
+			     verify_pack_usage, 0);
+	if (argc < 1)
+		usage_with_options(verify_pack_usage, verify_pack_options);
+	for (i = 0; i < argc; i++) {
+		if (verify_one_pack(argv[i], flags))
+			err = 1;
+		discard_revindex();
+	}
+
+	return err;
+}
diff --git a/builtin/verify-tag.c b/builtin/verify-tag.c
new file mode 100644
index 0000000..9f482c2
--- /dev/null
+++ b/builtin/verify-tag.c
@@ -0,0 +1,114 @@
+/*
+ * Builtin "git verify-tag"
+ *
+ * Copyright (c) 2007 Carlos Rica <jasampler@gmail.com>
+ *
+ * Based on git-verify-tag.sh
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "tag.h"
+#include "run-command.h"
+#include <signal.h>
+#include "parse-options.h"
+
+static const char * const verify_tag_usage[] = {
+		"git verify-tag [-v|--verbose] <tag>...",
+		NULL
+};
+
+#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
+
+static int run_gpg_verify(const char *buf, unsigned long size, int verbose)
+{
+	struct child_process gpg;
+	const char *args_gpg[] = {"gpg", "--verify", "FILE", "-", NULL};
+	char path[PATH_MAX], *eol;
+	size_t len;
+	int fd, ret;
+
+	fd = git_mkstemp(path, PATH_MAX, ".git_vtag_tmpXXXXXX");
+	if (fd < 0)
+		return error("could not create temporary file '%s': %s",
+						path, strerror(errno));
+	if (write_in_full(fd, buf, size) < 0)
+		return error("failed writing temporary file '%s': %s",
+						path, strerror(errno));
+	close(fd);
+
+	/* find the length without signature */
+	len = 0;
+	while (len < size && prefixcmp(buf + len, PGP_SIGNATURE)) {
+		eol = memchr(buf + len, '\n', size - len);
+		len += eol ? eol - (buf + len) + 1 : size - len;
+	}
+	if (verbose)
+		write_in_full(1, buf, len);
+
+	memset(&gpg, 0, sizeof(gpg));
+	gpg.argv = args_gpg;
+	gpg.in = -1;
+	args_gpg[2] = path;
+	if (start_command(&gpg)) {
+		unlink(path);
+		return error("could not run gpg.");
+	}
+
+	write_in_full(gpg.in, buf, len);
+	close(gpg.in);
+	ret = finish_command(&gpg);
+
+	unlink_or_warn(path);
+
+	return ret;
+}
+
+static int verify_tag(const char *name, int verbose)
+{
+	enum object_type type;
+	unsigned char sha1[20];
+	char *buf;
+	unsigned long size;
+	int ret;
+
+	if (get_sha1(name, sha1))
+		return error("tag '%s' not found.", name);
+
+	type = sha1_object_info(sha1, NULL);
+	if (type != OBJ_TAG)
+		return error("%s: cannot verify a non-tag object of type %s.",
+				name, typename(type));
+
+	buf = read_sha1_file(sha1, &type, &size);
+	if (!buf)
+		return error("%s: unable to read file.", name);
+
+	ret = run_gpg_verify(buf, size, verbose);
+
+	free(buf);
+	return ret;
+}
+
+int cmd_verify_tag(int argc, const char **argv, const char *prefix)
+{
+	int i = 1, verbose = 0, had_error = 0;
+	const struct option verify_tag_options[] = {
+		OPT__VERBOSE(&verbose),
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+
+	argc = parse_options(argc, argv, prefix, verify_tag_options,
+			     verify_tag_usage, PARSE_OPT_KEEP_ARGV0);
+	if (argc <= i)
+		usage_with_options(verify_tag_usage, verify_tag_options);
+
+	/* sometimes the program was terminated because this signal
+	 * was received in the process of writing the gpg input: */
+	signal(SIGPIPE, SIG_IGN);
+	while (i < argc)
+		if (verify_tag(argv[i++], verbose))
+			had_error = 1;
+	return had_error;
+}
diff --git a/builtin/write-tree.c b/builtin/write-tree.c
new file mode 100644
index 0000000..b223af4
--- /dev/null
+++ b/builtin/write-tree.c
@@ -0,0 +1,56 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "builtin.h"
+#include "cache.h"
+#include "tree.h"
+#include "cache-tree.h"
+#include "parse-options.h"
+
+static const char * const write_tree_usage[] = {
+	"git write-tree [--missing-ok] [--prefix=<prefix>/]",
+	NULL
+};
+
+int cmd_write_tree(int argc, const char **argv, const char *unused_prefix)
+{
+	int flags = 0, ret;
+	const char *prefix = NULL;
+	unsigned char sha1[20];
+	const char *me = "git-write-tree";
+	struct option write_tree_options[] = {
+		OPT_BIT(0, "missing-ok", &flags, "allow missing objects",
+			WRITE_TREE_MISSING_OK),
+		{ OPTION_STRING, 0, "prefix", &prefix, "<prefix>/",
+		  "write tree object for a subdirectory <prefix>" ,
+		  PARSE_OPT_LITERAL_ARGHELP },
+		{ OPTION_BIT, 0, "ignore-cache-tree", &flags, NULL,
+		  "only useful for debugging",
+		  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, NULL,
+		  WRITE_TREE_IGNORE_CACHE_TREE },
+		OPT_END()
+	};
+
+	git_config(git_default_config, NULL);
+	argc = parse_options(argc, argv, unused_prefix, write_tree_options,
+			     write_tree_usage, 0);
+
+	ret = write_cache_as_tree(sha1, flags, prefix);
+	switch (ret) {
+	case 0:
+		printf("%s\n", sha1_to_hex(sha1));
+		break;
+	case WRITE_TREE_UNREADABLE_INDEX:
+		die("%s: error reading the index", me);
+		break;
+	case WRITE_TREE_UNMERGED_INDEX:
+		die("%s: error building trees", me);
+		break;
+	case WRITE_TREE_PREFIX_ERROR:
+		die("%s: prefix %s not found", me, prefix);
+		break;
+	}
+	return ret;
+}