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-rw-r--r--merge-recursive.c1770
1 files changed, 1770 insertions, 0 deletions
diff --git a/merge-recursive.c b/merge-recursive.c
new file mode 100644
index 0000000..8f72b2c
--- /dev/null
+++ b/merge-recursive.c
@@ -0,0 +1,1770 @@
+/*
+ * Recursive Merge algorithm stolen from git-merge-recursive.py by
+ * Fredrik Kuivinen.
+ * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
+ */
+#include "cache.h"
+#include "cache-tree.h"
+#include "commit.h"
+#include "blob.h"
+#include "tree-walk.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "run-command.h"
+#include "tag.h"
+#include "unpack-trees.h"
+#include "path-list.h"
+#include "xdiff-interface.h"
+#include "interpolate.h"
+#include "attr.h"
+
+static int subtree_merge;
+
+static struct tree *shift_tree_object(struct tree *one, struct tree *two)
+{
+ unsigned char shifted[20];
+
+ /*
+ * NEEDSWORK: this limits the recursion depth to hardcoded
+ * value '2' to avoid excessive overhead.
+ */
+ shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
+ if (!hashcmp(two->object.sha1, shifted))
+ return two;
+ return lookup_tree(shifted);
+}
+
+/*
+ * A virtual commit has
+ * - (const char *)commit->util set to the name, and
+ * - *(int *)commit->object.sha1 set to the virtual id.
+ */
+
+static unsigned commit_list_count(const struct commit_list *l)
+{
+ unsigned c = 0;
+ for (; l; l = l->next )
+ c++;
+ return c;
+}
+
+static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
+{
+ struct commit *commit = xcalloc(1, sizeof(struct commit));
+ static unsigned virtual_id = 1;
+ commit->tree = tree;
+ commit->util = (void*)comment;
+ *(int*)commit->object.sha1 = virtual_id++;
+ /* avoid warnings */
+ commit->object.parsed = 1;
+ return commit;
+}
+
+/*
+ * Since we use get_tree_entry(), which does not put the read object into
+ * the object pool, we cannot rely on a == b.
+ */
+static int sha_eq(const unsigned char *a, const unsigned char *b)
+{
+ if (!a && !b)
+ return 2;
+ return a && b && hashcmp(a, b) == 0;
+}
+
+/*
+ * Since we want to write the index eventually, we cannot reuse the index
+ * for these (temporary) data.
+ */
+struct stage_data
+{
+ struct
+ {
+ unsigned mode;
+ unsigned char sha[20];
+ } stages[4];
+ unsigned processed:1;
+};
+
+struct output_buffer
+{
+ struct output_buffer *next;
+ char *str;
+};
+
+static struct path_list current_file_set = {NULL, 0, 0, 1};
+static struct path_list current_directory_set = {NULL, 0, 0, 1};
+
+static int call_depth = 0;
+static int verbosity = 2;
+static int buffer_output = 1;
+static struct output_buffer *output_list, *output_end;
+
+static int show (int v)
+{
+ return (!call_depth && verbosity >= v) || verbosity >= 5;
+}
+
+static void output(int v, const char *fmt, ...)
+{
+ va_list args;
+ va_start(args, fmt);
+ if (buffer_output && show(v)) {
+ struct output_buffer *b = xmalloc(sizeof(*b));
+ nfvasprintf(&b->str, fmt, args);
+ b->next = NULL;
+ if (output_end)
+ output_end->next = b;
+ else
+ output_list = b;
+ output_end = b;
+ } else if (show(v)) {
+ int i;
+ for (i = call_depth; i--;)
+ fputs(" ", stdout);
+ vfprintf(stdout, fmt, args);
+ fputc('\n', stdout);
+ }
+ va_end(args);
+}
+
+static void flush_output()
+{
+ struct output_buffer *b, *n;
+ for (b = output_list; b; b = n) {
+ int i;
+ for (i = call_depth; i--;)
+ fputs(" ", stdout);
+ fputs(b->str, stdout);
+ fputc('\n', stdout);
+ n = b->next;
+ free(b->str);
+ free(b);
+ }
+ output_list = NULL;
+ output_end = NULL;
+}
+
+static void output_commit_title(struct commit *commit)
+{
+ int i;
+ flush_output();
+ for (i = call_depth; i--;)
+ fputs(" ", stdout);
+ if (commit->util)
+ printf("virtual %s\n", (char *)commit->util);
+ else {
+ printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
+ if (parse_commit(commit) != 0)
+ printf("(bad commit)\n");
+ else {
+ const char *s;
+ int len;
+ for (s = commit->buffer; *s; s++)
+ if (*s == '\n' && s[1] == '\n') {
+ s += 2;
+ break;
+ }
+ for (len = 0; s[len] && '\n' != s[len]; len++)
+ ; /* do nothing */
+ printf("%.*s\n", len, s);
+ }
+ }
+}
+
+static struct cache_entry *make_cache_entry(unsigned int mode,
+ const unsigned char *sha1, const char *path, int stage, int refresh)
+{
+ int size, len;
+ struct cache_entry *ce;
+
+ if (!verify_path(path))
+ return NULL;
+
+ 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 (refresh)
+ return refresh_cache_entry(ce, 0);
+
+ return ce;
+}
+
+static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
+ const char *path, int stage, int refresh, int options)
+{
+ struct cache_entry *ce;
+ ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
+ if (!ce)
+ return error("addinfo_cache failed for path '%s'", path);
+ return add_cache_entry(ce, options);
+}
+
+/*
+ * This is a global variable which is used in a number of places but
+ * only written to in the 'merge' function.
+ *
+ * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
+ * don't update the working directory.
+ * 0 => Leave unmerged entries in the cache and update
+ * the working directory.
+ */
+static int index_only = 0;
+
+static int git_merge_trees(int index_only,
+ struct tree *common,
+ struct tree *head,
+ struct tree *merge)
+{
+ int rc;
+ struct object_list *trees = NULL;
+ struct unpack_trees_options opts;
+
+ memset(&opts, 0, sizeof(opts));
+ if (index_only)
+ opts.index_only = 1;
+ else
+ opts.update = 1;
+ opts.merge = 1;
+ opts.head_idx = 2;
+ opts.fn = threeway_merge;
+
+ object_list_append(&common->object, &trees);
+ object_list_append(&head->object, &trees);
+ object_list_append(&merge->object, &trees);
+
+ rc = unpack_trees(trees, &opts);
+ cache_tree_free(&active_cache_tree);
+ return rc;
+}
+
+static int unmerged_index(void)
+{
+ int i;
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ if (ce_stage(ce))
+ return 1;
+ }
+ return 0;
+}
+
+static struct tree *git_write_tree(void)
+{
+ struct tree *result = NULL;
+
+ if (unmerged_index()) {
+ int i;
+ output(0, "There are unmerged index entries:");
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ if (ce_stage(ce))
+ output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
+ }
+ return NULL;
+ }
+
+ if (!active_cache_tree)
+ active_cache_tree = cache_tree();
+
+ if (!cache_tree_fully_valid(active_cache_tree) &&
+ cache_tree_update(active_cache_tree,
+ active_cache, active_nr, 0, 0) < 0)
+ die("error building trees");
+
+ result = lookup_tree(active_cache_tree->sha1);
+
+ return result;
+}
+
+static int save_files_dirs(const unsigned char *sha1,
+ const char *base, int baselen, const char *path,
+ unsigned int mode, int stage)
+{
+ int len = strlen(path);
+ char *newpath = xmalloc(baselen + len + 1);
+ memcpy(newpath, base, baselen);
+ memcpy(newpath + baselen, path, len);
+ newpath[baselen + len] = '\0';
+
+ if (S_ISDIR(mode))
+ path_list_insert(newpath, &current_directory_set);
+ else
+ path_list_insert(newpath, &current_file_set);
+ free(newpath);
+
+ return READ_TREE_RECURSIVE;
+}
+
+static int get_files_dirs(struct tree *tree)
+{
+ int n;
+ if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
+ return 0;
+ n = current_file_set.nr + current_directory_set.nr;
+ return n;
+}
+
+/*
+ * Returns a index_entry instance which doesn't have to correspond to
+ * a real cache entry in Git's index.
+ */
+static struct stage_data *insert_stage_data(const char *path,
+ struct tree *o, struct tree *a, struct tree *b,
+ struct path_list *entries)
+{
+ struct path_list_item *item;
+ struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
+ get_tree_entry(o->object.sha1, path,
+ e->stages[1].sha, &e->stages[1].mode);
+ get_tree_entry(a->object.sha1, path,
+ e->stages[2].sha, &e->stages[2].mode);
+ get_tree_entry(b->object.sha1, path,
+ e->stages[3].sha, &e->stages[3].mode);
+ item = path_list_insert(path, entries);
+ item->util = e;
+ return e;
+}
+
+/*
+ * Create a dictionary mapping file names to stage_data objects. The
+ * dictionary contains one entry for every path with a non-zero stage entry.
+ */
+static struct path_list *get_unmerged(void)
+{
+ struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
+ int i;
+
+ unmerged->strdup_paths = 1;
+
+ for (i = 0; i < active_nr; i++) {
+ struct path_list_item *item;
+ struct stage_data *e;
+ struct cache_entry *ce = active_cache[i];
+ if (!ce_stage(ce))
+ continue;
+
+ item = path_list_lookup(ce->name, unmerged);
+ if (!item) {
+ item = path_list_insert(ce->name, unmerged);
+ item->util = xcalloc(1, sizeof(struct stage_data));
+ }
+ e = item->util;
+ e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
+ hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
+ }
+
+ return unmerged;
+}
+
+struct rename
+{
+ struct diff_filepair *pair;
+ struct stage_data *src_entry;
+ struct stage_data *dst_entry;
+ unsigned processed:1;
+};
+
+/*
+ * Get information of all renames which occurred between 'o_tree' and
+ * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
+ * 'b_tree') to be able to associate the correct cache entries with
+ * the rename information. 'tree' is always equal to either a_tree or b_tree.
+ */
+static struct path_list *get_renames(struct tree *tree,
+ struct tree *o_tree,
+ struct tree *a_tree,
+ struct tree *b_tree,
+ struct path_list *entries)
+{
+ int i;
+ struct path_list *renames;
+ struct diff_options opts;
+
+ renames = xcalloc(1, sizeof(struct path_list));
+ diff_setup(&opts);
+ opts.recursive = 1;
+ opts.detect_rename = DIFF_DETECT_RENAME;
+ opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+ if (diff_setup_done(&opts) < 0)
+ die("diff setup failed");
+ diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
+ diffcore_std(&opts);
+ for (i = 0; i < diff_queued_diff.nr; ++i) {
+ struct path_list_item *item;
+ struct rename *re;
+ struct diff_filepair *pair = diff_queued_diff.queue[i];
+ if (pair->status != 'R') {
+ diff_free_filepair(pair);
+ continue;
+ }
+ re = xmalloc(sizeof(*re));
+ re->processed = 0;
+ re->pair = pair;
+ item = path_list_lookup(re->pair->one->path, entries);
+ if (!item)
+ re->src_entry = insert_stage_data(re->pair->one->path,
+ o_tree, a_tree, b_tree, entries);
+ else
+ re->src_entry = item->util;
+
+ item = path_list_lookup(re->pair->two->path, entries);
+ if (!item)
+ re->dst_entry = insert_stage_data(re->pair->two->path,
+ o_tree, a_tree, b_tree, entries);
+ else
+ re->dst_entry = item->util;
+ item = path_list_insert(pair->one->path, renames);
+ item->util = re;
+ }
+ opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+ diff_queued_diff.nr = 0;
+ diff_flush(&opts);
+ return renames;
+}
+
+static int update_stages(const char *path, struct diff_filespec *o,
+ struct diff_filespec *a, struct diff_filespec *b,
+ int clear)
+{
+ int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
+ if (clear)
+ if (remove_file_from_cache(path))
+ return -1;
+ if (o)
+ if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
+ return -1;
+ if (a)
+ if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
+ return -1;
+ if (b)
+ if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
+ return -1;
+ return 0;
+}
+
+static int remove_path(const char *name)
+{
+ int ret, len;
+ char *slash, *dirs;
+
+ ret = unlink(name);
+ if (ret)
+ return ret;
+ len = strlen(name);
+ dirs = xmalloc(len+1);
+ memcpy(dirs, name, len);
+ dirs[len] = '\0';
+ while ((slash = strrchr(name, '/'))) {
+ *slash = '\0';
+ len = slash - name;
+ if (rmdir(name) != 0)
+ break;
+ }
+ free(dirs);
+ return ret;
+}
+
+static int remove_file(int clean, const char *path, int no_wd)
+{
+ int update_cache = index_only || clean;
+ int update_working_directory = !index_only && !no_wd;
+
+ if (update_cache) {
+ if (remove_file_from_cache(path))
+ return -1;
+ }
+ if (update_working_directory) {
+ unlink(path);
+ if (errno != ENOENT || errno != EISDIR)
+ return -1;
+ remove_path(path);
+ }
+ return 0;
+}
+
+static char *unique_path(const char *path, const char *branch)
+{
+ char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
+ int suffix = 0;
+ struct stat st;
+ char *p = newpath + strlen(path);
+ strcpy(newpath, path);
+ *(p++) = '~';
+ strcpy(p, branch);
+ for (; *p; ++p)
+ if ('/' == *p)
+ *p = '_';
+ while (path_list_has_path(&current_file_set, newpath) ||
+ path_list_has_path(&current_directory_set, newpath) ||
+ lstat(newpath, &st) == 0)
+ sprintf(p, "_%d", suffix++);
+
+ path_list_insert(newpath, &current_file_set);
+ return newpath;
+}
+
+static int mkdir_p(const char *path, unsigned long mode)
+{
+ /* path points to cache entries, so xstrdup before messing with it */
+ char *buf = xstrdup(path);
+ int result = safe_create_leading_directories(buf);
+ free(buf);
+ return result;
+}
+
+static void flush_buffer(int fd, const char *buf, unsigned long size)
+{
+ while (size > 0) {
+ long ret = write_in_full(fd, buf, size);
+ if (ret < 0) {
+ /* Ignore epipe */
+ if (errno == EPIPE)
+ break;
+ die("merge-recursive: %s", strerror(errno));
+ } else if (!ret) {
+ die("merge-recursive: disk full?");
+ }
+ size -= ret;
+ buf += ret;
+ }
+}
+
+static int make_room_for_path(const char *path)
+{
+ int status;
+ const char *msg = "failed to create path '%s'%s";
+
+ status = mkdir_p(path, 0777);
+ if (status) {
+ if (status == -3) {
+ /* something else exists */
+ error(msg, path, ": perhaps a D/F conflict?");
+ return -1;
+ }
+ die(msg, path, "");
+ }
+
+ /* Successful unlink is good.. */
+ if (!unlink(path))
+ return 0;
+ /* .. and so is no existing file */
+ if (errno == ENOENT)
+ return 0;
+ /* .. but not some other error (who really cares what?) */
+ return error(msg, path, ": perhaps a D/F conflict?");
+}
+
+static void update_file_flags(const unsigned char *sha,
+ unsigned mode,
+ const char *path,
+ int update_cache,
+ int update_wd)
+{
+ if (index_only)
+ update_wd = 0;
+
+ if (update_wd) {
+ enum object_type type;
+ void *buf;
+ unsigned long size;
+
+ buf = read_sha1_file(sha, &type, &size);
+ if (!buf)
+ die("cannot read object %s '%s'", sha1_to_hex(sha), path);
+ if (type != OBJ_BLOB)
+ die("blob expected for %s '%s'", sha1_to_hex(sha), path);
+
+ if (make_room_for_path(path) < 0) {
+ update_wd = 0;
+ goto update_index;
+ }
+ if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
+ int fd;
+ if (mode & 0100)
+ mode = 0777;
+ else
+ mode = 0666;
+ fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
+ if (fd < 0)
+ die("failed to open %s: %s", path, strerror(errno));
+ flush_buffer(fd, buf, size);
+ close(fd);
+ } else if (S_ISLNK(mode)) {
+ char *lnk = xmalloc(size + 1);
+ memcpy(lnk, buf, size);
+ lnk[size] = '\0';
+ mkdir_p(path, 0777);
+ unlink(path);
+ symlink(lnk, path);
+ free(lnk);
+ } else
+ die("do not know what to do with %06o %s '%s'",
+ mode, sha1_to_hex(sha), path);
+ }
+ update_index:
+ if (update_cache)
+ add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
+}
+
+static void update_file(int clean,
+ const unsigned char *sha,
+ unsigned mode,
+ const char *path)
+{
+ update_file_flags(sha, mode, path, index_only || clean, !index_only);
+}
+
+/* Low level file merging, update and removal */
+
+struct merge_file_info
+{
+ unsigned char sha[20];
+ unsigned mode;
+ unsigned clean:1,
+ merge:1;
+};
+
+static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
+{
+ unsigned long size;
+ enum object_type type;
+
+ if (!hashcmp(sha1, null_sha1)) {
+ mm->ptr = xstrdup("");
+ mm->size = 0;
+ return;
+ }
+
+ mm->ptr = read_sha1_file(sha1, &type, &size);
+ if (!mm->ptr || type != OBJ_BLOB)
+ die("unable to read blob object %s", sha1_to_hex(sha1));
+ mm->size = size;
+}
+
+/*
+ * Customizable low-level merge drivers support.
+ */
+
+struct ll_merge_driver;
+typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
+ const char *path,
+ mmfile_t *orig,
+ mmfile_t *src1, const char *name1,
+ mmfile_t *src2, const char *name2,
+ mmbuffer_t *result);
+
+struct ll_merge_driver {
+ const char *name;
+ const char *description;
+ ll_merge_fn fn;
+ const char *recursive;
+ struct ll_merge_driver *next;
+ char *cmdline;
+};
+
+/*
+ * Built-in low-levels
+ */
+static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
+ const char *path_unused,
+ mmfile_t *orig,
+ mmfile_t *src1, const char *name1,
+ mmfile_t *src2, const char *name2,
+ mmbuffer_t *result)
+{
+ xpparam_t xpp;
+
+ memset(&xpp, 0, sizeof(xpp));
+ return xdl_merge(orig,
+ src1, name1,
+ src2, name2,
+ &xpp, XDL_MERGE_ZEALOUS,
+ result);
+}
+
+static int ll_union_merge(const struct ll_merge_driver *drv_unused,
+ const char *path_unused,
+ mmfile_t *orig,
+ mmfile_t *src1, const char *name1,
+ mmfile_t *src2, const char *name2,
+ mmbuffer_t *result)
+{
+ char *src, *dst;
+ long size;
+ const int marker_size = 7;
+
+ int status = ll_xdl_merge(drv_unused, path_unused,
+ orig, src1, NULL, src2, NULL, result);
+ if (status <= 0)
+ return status;
+ size = result->size;
+ src = dst = result->ptr;
+ while (size) {
+ char ch;
+ if ((marker_size < size) &&
+ (*src == '<' || *src == '=' || *src == '>')) {
+ int i;
+ ch = *src;
+ for (i = 0; i < marker_size; i++)
+ if (src[i] != ch)
+ goto not_a_marker;
+ if (src[marker_size] != '\n')
+ goto not_a_marker;
+ src += marker_size + 1;
+ size -= marker_size + 1;
+ continue;
+ }
+ not_a_marker:
+ do {
+ ch = *src++;
+ *dst++ = ch;
+ size--;
+ } while (ch != '\n' && size);
+ }
+ result->size = dst - result->ptr;
+ return 0;
+}
+
+static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
+ const char *path_unused,
+ mmfile_t *orig,
+ mmfile_t *src1, const char *name1,
+ mmfile_t *src2, const char *name2,
+ mmbuffer_t *result)
+{
+ /*
+ * The tentative merge result is "ours" for the final round,
+ * or common ancestor for an internal merge. Still return
+ * "conflicted merge" status.
+ */
+ mmfile_t *stolen = index_only ? orig : src1;
+
+ result->ptr = stolen->ptr;
+ result->size = stolen->size;
+ stolen->ptr = NULL;
+ return 1;
+}
+
+#define LL_BINARY_MERGE 0
+#define LL_TEXT_MERGE 1
+#define LL_UNION_MERGE 2
+static struct ll_merge_driver ll_merge_drv[] = {
+ { "binary", "built-in binary merge", ll_binary_merge },
+ { "text", "built-in 3-way text merge", ll_xdl_merge },
+ { "union", "built-in union merge", ll_union_merge },
+};
+
+static void create_temp(mmfile_t *src, char *path)
+{
+ int fd;
+
+ strcpy(path, ".merge_file_XXXXXX");
+ fd = mkstemp(path);
+ if (fd < 0)
+ die("unable to create temp-file");
+ if (write_in_full(fd, src->ptr, src->size) != src->size)
+ die("unable to write temp-file");
+ close(fd);
+}
+
+/*
+ * User defined low-level merge driver support.
+ */
+static int ll_ext_merge(const struct ll_merge_driver *fn,
+ const char *path,
+ mmfile_t *orig,
+ mmfile_t *src1, const char *name1,
+ mmfile_t *src2, const char *name2,
+ mmbuffer_t *result)
+{
+ char temp[3][50];
+ char cmdbuf[2048];
+ struct interp table[] = {
+ { "%O" },
+ { "%A" },
+ { "%B" },
+ };
+ struct child_process child;
+ const char *args[20];
+ int status, fd, i;
+ struct stat st;
+
+ if (fn->cmdline == NULL)
+ die("custom merge driver %s lacks command line.", fn->name);
+
+ result->ptr = NULL;
+ result->size = 0;
+ create_temp(orig, temp[0]);
+ create_temp(src1, temp[1]);
+ create_temp(src2, temp[2]);
+
+ interp_set_entry(table, 0, temp[0]);
+ interp_set_entry(table, 1, temp[1]);
+ interp_set_entry(table, 2, temp[2]);
+
+ output(1, "merging %s using %s", path,
+ fn->description ? fn->description : fn->name);
+
+ interpolate(cmdbuf, sizeof(cmdbuf), fn->cmdline, table, 3);
+
+ memset(&child, 0, sizeof(child));
+ child.argv = args;
+ args[0] = "sh";
+ args[1] = "-c";
+ args[2] = cmdbuf;
+ args[3] = NULL;
+
+ status = run_command(&child);
+ if (status < -ERR_RUN_COMMAND_FORK)
+ ; /* failure in run-command */
+ else
+ status = -status;
+ fd = open(temp[1], O_RDONLY);
+ if (fd < 0)
+ goto bad;
+ if (fstat(fd, &st))
+ goto close_bad;
+ result->size = st.st_size;
+ result->ptr = xmalloc(result->size + 1);
+ if (read_in_full(fd, result->ptr, result->size) != result->size) {
+ free(result->ptr);
+ result->ptr = NULL;
+ result->size = 0;
+ }
+ close_bad:
+ close(fd);
+ bad:
+ for (i = 0; i < 3; i++)
+ unlink(temp[i]);
+ return status;
+}
+
+/*
+ * merge.default and merge.driver configuration items
+ */
+static struct ll_merge_driver *ll_user_merge, **ll_user_merge_tail;
+static const char *default_ll_merge;
+
+static int read_merge_config(const char *var, const char *value)
+{
+ struct ll_merge_driver *fn;
+ const char *ep, *name;
+ int namelen;
+
+ if (!strcmp(var, "merge.default")) {
+ if (value)
+ default_ll_merge = strdup(value);
+ return 0;
+ }
+
+ /*
+ * We are not interested in anything but "merge.<name>.variable";
+ * especially, we do not want to look at variables such as
+ * "merge.summary", "merge.tool", and "merge.verbosity".
+ */
+ if (prefixcmp(var, "merge.") || (ep = strrchr(var, '.')) == var + 5)
+ return 0;
+
+ /*
+ * Find existing one as we might be processing merge.<name>.var2
+ * after seeing merge.<name>.var1.
+ */
+ name = var + 6;
+ namelen = ep - name;
+ for (fn = ll_user_merge; fn; fn = fn->next)
+ if (!strncmp(fn->name, name, namelen) && !fn->name[namelen])
+ break;
+ if (!fn) {
+ char *namebuf;
+ fn = xcalloc(1, sizeof(struct ll_merge_driver));
+ namebuf = xmalloc(namelen + 1);
+ memcpy(namebuf, name, namelen);
+ namebuf[namelen] = 0;
+ fn->name = namebuf;
+ fn->fn = ll_ext_merge;
+ fn->next = NULL;
+ *ll_user_merge_tail = fn;
+ ll_user_merge_tail = &(fn->next);
+ }
+
+ ep++;
+
+ if (!strcmp("name", ep)) {
+ if (!value)
+ return error("%s: lacks value", var);
+ fn->description = strdup(value);
+ return 0;
+ }
+
+ if (!strcmp("driver", ep)) {
+ if (!value)
+ return error("%s: lacks value", var);
+ /*
+ * merge.<name>.driver specifies the command line:
+ *
+ * command-line
+ *
+ * The command-line will be interpolated with the following
+ * tokens and is given to the shell:
+ *
+ * %O - temporary file name for the merge base.
+ * %A - temporary file name for our version.
+ * %B - temporary file name for the other branches' version.
+ *
+ * The external merge driver should write the results in the
+ * file named by %A, and signal that it has done with zero exit
+ * status.
+ */
+ fn->cmdline = strdup(value);
+ return 0;
+ }
+
+ if (!strcmp("recursive", ep)) {
+ if (!value)
+ return error("%s: lacks value", var);
+ fn->recursive = strdup(value);
+ return 0;
+ }
+
+ return 0;
+}
+
+static void initialize_ll_merge(void)
+{
+ if (ll_user_merge_tail)
+ return;
+ ll_user_merge_tail = &ll_user_merge;
+ git_config(read_merge_config);
+}
+
+static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr)
+{
+ struct ll_merge_driver *fn;
+ const char *name;
+ int i;
+
+ initialize_ll_merge();
+
+ if (ATTR_TRUE(merge_attr))
+ return &ll_merge_drv[LL_TEXT_MERGE];
+ else if (ATTR_FALSE(merge_attr))
+ return &ll_merge_drv[LL_BINARY_MERGE];
+ else if (ATTR_UNSET(merge_attr)) {
+ if (!default_ll_merge)
+ return &ll_merge_drv[LL_TEXT_MERGE];
+ else
+ name = default_ll_merge;
+ }
+ else
+ name = merge_attr;
+
+ for (fn = ll_user_merge; fn; fn = fn->next)
+ if (!strcmp(fn->name, name))
+ return fn;
+
+ for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++)
+ if (!strcmp(ll_merge_drv[i].name, name))
+ return &ll_merge_drv[i];
+
+ /* default to the 3-way */
+ return &ll_merge_drv[LL_TEXT_MERGE];
+}
+
+static const char *git_path_check_merge(const char *path)
+{
+ static struct git_attr_check attr_merge_check;
+
+ if (!attr_merge_check.attr)
+ attr_merge_check.attr = git_attr("merge", 5);
+
+ if (git_checkattr(path, 1, &attr_merge_check))
+ return NULL;
+ return attr_merge_check.value;
+}
+
+static int ll_merge(mmbuffer_t *result_buf,
+ struct diff_filespec *o,
+ struct diff_filespec *a,
+ struct diff_filespec *b,
+ const char *branch1,
+ const char *branch2)
+{
+ mmfile_t orig, src1, src2;
+ char *name1, *name2;
+ int merge_status;
+ const char *ll_driver_name;
+ const struct ll_merge_driver *driver;
+
+ name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
+ name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
+
+ fill_mm(o->sha1, &orig);
+ fill_mm(a->sha1, &src1);
+ fill_mm(b->sha1, &src2);
+
+ ll_driver_name = git_path_check_merge(a->path);
+ driver = find_ll_merge_driver(ll_driver_name);
+
+ if (index_only && driver->recursive)
+ driver = find_ll_merge_driver(driver->recursive);
+ merge_status = driver->fn(driver, a->path,
+ &orig, &src1, name1, &src2, name2,
+ result_buf);
+
+ free(name1);
+ free(name2);
+ free(orig.ptr);
+ free(src1.ptr);
+ free(src2.ptr);
+ return merge_status;
+}
+
+static struct merge_file_info merge_file(struct diff_filespec *o,
+ struct diff_filespec *a, struct diff_filespec *b,
+ const char *branch1, const char *branch2)
+{
+ struct merge_file_info result;
+ result.merge = 0;
+ result.clean = 1;
+
+ if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
+ result.clean = 0;
+ if (S_ISREG(a->mode)) {
+ result.mode = a->mode;
+ hashcpy(result.sha, a->sha1);
+ } else {
+ result.mode = b->mode;
+ hashcpy(result.sha, b->sha1);
+ }
+ } else {
+ if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
+ result.merge = 1;
+
+ result.mode = a->mode == o->mode ? b->mode: a->mode;
+
+ if (sha_eq(a->sha1, o->sha1))
+ hashcpy(result.sha, b->sha1);
+ else if (sha_eq(b->sha1, o->sha1))
+ hashcpy(result.sha, a->sha1);
+ else if (S_ISREG(a->mode)) {
+ mmbuffer_t result_buf;
+ int merge_status;
+
+ merge_status = ll_merge(&result_buf, o, a, b,
+ branch1, branch2);
+
+ if ((merge_status < 0) || !result_buf.ptr)
+ die("Failed to execute internal merge");
+
+ if (write_sha1_file(result_buf.ptr, result_buf.size,
+ blob_type, result.sha))
+ die("Unable to add %s to database",
+ a->path);
+
+ free(result_buf.ptr);
+ result.clean = (merge_status == 0);
+ } else {
+ if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
+ die("cannot merge modes?");
+
+ hashcpy(result.sha, a->sha1);
+
+ if (!sha_eq(a->sha1, b->sha1))
+ result.clean = 0;
+ }
+ }
+
+ return result;
+}
+
+static void conflict_rename_rename(struct rename *ren1,
+ const char *branch1,
+ struct rename *ren2,
+ const char *branch2)
+{
+ char *del[2];
+ int delp = 0;
+ const char *ren1_dst = ren1->pair->two->path;
+ const char *ren2_dst = ren2->pair->two->path;
+ const char *dst_name1 = ren1_dst;
+ const char *dst_name2 = ren2_dst;
+ if (path_list_has_path(&current_directory_set, ren1_dst)) {
+ dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
+ output(1, "%s is a directory in %s added as %s instead",
+ ren1_dst, branch2, dst_name1);
+ remove_file(0, ren1_dst, 0);
+ }
+ if (path_list_has_path(&current_directory_set, ren2_dst)) {
+ dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
+ output(1, "%s is a directory in %s added as %s instead",
+ ren2_dst, branch1, dst_name2);
+ remove_file(0, ren2_dst, 0);
+ }
+ if (index_only) {
+ remove_file_from_cache(dst_name1);
+ remove_file_from_cache(dst_name2);
+ /*
+ * Uncomment to leave the conflicting names in the resulting tree
+ *
+ * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
+ * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
+ */
+ } else {
+ update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
+ update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
+ }
+ while (delp--)
+ free(del[delp]);
+}
+
+static void conflict_rename_dir(struct rename *ren1,
+ const char *branch1)
+{
+ char *new_path = unique_path(ren1->pair->two->path, branch1);
+ output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
+ remove_file(0, ren1->pair->two->path, 0);
+ update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
+ free(new_path);
+}
+
+static void conflict_rename_rename_2(struct rename *ren1,
+ const char *branch1,
+ struct rename *ren2,
+ const char *branch2)
+{
+ char *new_path1 = unique_path(ren1->pair->two->path, branch1);
+ char *new_path2 = unique_path(ren2->pair->two->path, branch2);
+ output(1, "Renamed %s to %s and %s to %s instead",
+ ren1->pair->one->path, new_path1,
+ ren2->pair->one->path, new_path2);
+ remove_file(0, ren1->pair->two->path, 0);
+ update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
+ update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
+ free(new_path2);
+ free(new_path1);
+}
+
+static int process_renames(struct path_list *a_renames,
+ struct path_list *b_renames,
+ const char *a_branch,
+ const char *b_branch)
+{
+ int clean_merge = 1, i, j;
+ struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
+ const struct rename *sre;
+
+ for (i = 0; i < a_renames->nr; i++) {
+ sre = a_renames->items[i].util;
+ path_list_insert(sre->pair->two->path, &a_by_dst)->util
+ = sre->dst_entry;
+ }
+ for (i = 0; i < b_renames->nr; i++) {
+ sre = b_renames->items[i].util;
+ path_list_insert(sre->pair->two->path, &b_by_dst)->util
+ = sre->dst_entry;
+ }
+
+ for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
+ int compare;
+ char *src;
+ struct path_list *renames1, *renames2, *renames2Dst;
+ struct rename *ren1 = NULL, *ren2 = NULL;
+ const char *branch1, *branch2;
+ const char *ren1_src, *ren1_dst;
+
+ if (i >= a_renames->nr) {
+ compare = 1;
+ ren2 = b_renames->items[j++].util;
+ } else if (j >= b_renames->nr) {
+ compare = -1;
+ ren1 = a_renames->items[i++].util;
+ } else {
+ compare = strcmp(a_renames->items[i].path,
+ b_renames->items[j].path);
+ if (compare <= 0)
+ ren1 = a_renames->items[i++].util;
+ if (compare >= 0)
+ ren2 = b_renames->items[j++].util;
+ }
+
+ /* TODO: refactor, so that 1/2 are not needed */
+ if (ren1) {
+ renames1 = a_renames;
+ renames2 = b_renames;
+ renames2Dst = &b_by_dst;
+ branch1 = a_branch;
+ branch2 = b_branch;
+ } else {
+ struct rename *tmp;
+ renames1 = b_renames;
+ renames2 = a_renames;
+ renames2Dst = &a_by_dst;
+ branch1 = b_branch;
+ branch2 = a_branch;
+ tmp = ren2;
+ ren2 = ren1;
+ ren1 = tmp;
+ }
+ src = ren1->pair->one->path;
+
+ ren1->dst_entry->processed = 1;
+ ren1->src_entry->processed = 1;
+
+ if (ren1->processed)
+ continue;
+ ren1->processed = 1;
+
+ ren1_src = ren1->pair->one->path;
+ ren1_dst = ren1->pair->two->path;
+
+ if (ren2) {
+ const char *ren2_src = ren2->pair->one->path;
+ const char *ren2_dst = ren2->pair->two->path;
+ /* Renamed in 1 and renamed in 2 */
+ if (strcmp(ren1_src, ren2_src) != 0)
+ die("ren1.src != ren2.src");
+ ren2->dst_entry->processed = 1;
+ ren2->processed = 1;
+ if (strcmp(ren1_dst, ren2_dst) != 0) {
+ clean_merge = 0;
+ output(1, "CONFLICT (rename/rename): "
+ "Rename \"%s\"->\"%s\" in branch \"%s\" "
+ "rename \"%s\"->\"%s\" in \"%s\"%s",
+ src, ren1_dst, branch1,
+ src, ren2_dst, branch2,
+ index_only ? " (left unresolved)": "");
+ if (index_only) {
+ remove_file_from_cache(src);
+ update_file(0, ren1->pair->one->sha1,
+ ren1->pair->one->mode, src);
+ }
+ conflict_rename_rename(ren1, branch1, ren2, branch2);
+ } else {
+ struct merge_file_info mfi;
+ remove_file(1, ren1_src, 1);
+ mfi = merge_file(ren1->pair->one,
+ ren1->pair->two,
+ ren2->pair->two,
+ branch1,
+ branch2);
+ if (mfi.merge || !mfi.clean)
+ output(1, "Renamed %s->%s", src, ren1_dst);
+
+ if (mfi.merge)
+ output(2, "Auto-merged %s", ren1_dst);
+
+ if (!mfi.clean) {
+ output(1, "CONFLICT (content): merge conflict in %s",
+ ren1_dst);
+ clean_merge = 0;
+
+ if (!index_only)
+ update_stages(ren1_dst,
+ ren1->pair->one,
+ ren1->pair->two,
+ ren2->pair->two,
+ 1 /* clear */);
+ }
+ update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
+ }
+ } else {
+ /* Renamed in 1, maybe changed in 2 */
+ struct path_list_item *item;
+ /* we only use sha1 and mode of these */
+ struct diff_filespec src_other, dst_other;
+ int try_merge, stage = a_renames == renames1 ? 3: 2;
+
+ remove_file(1, ren1_src, index_only || stage == 3);
+
+ hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
+ src_other.mode = ren1->src_entry->stages[stage].mode;
+ hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
+ dst_other.mode = ren1->dst_entry->stages[stage].mode;
+
+ try_merge = 0;
+
+ if (path_list_has_path(&current_directory_set, ren1_dst)) {
+ clean_merge = 0;
+ output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
+ " directory %s added in %s",
+ ren1_src, ren1_dst, branch1,
+ ren1_dst, branch2);
+ conflict_rename_dir(ren1, branch1);
+ } else if (sha_eq(src_other.sha1, null_sha1)) {
+ clean_merge = 0;
+ output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
+ "and deleted in %s",
+ ren1_src, ren1_dst, branch1,
+ branch2);
+ update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
+ } else if (!sha_eq(dst_other.sha1, null_sha1)) {
+ const char *new_path;
+ clean_merge = 0;
+ try_merge = 1;
+ output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
+ "%s added in %s",
+ ren1_src, ren1_dst, branch1,
+ ren1_dst, branch2);
+ new_path = unique_path(ren1_dst, branch2);
+ output(1, "Added as %s instead", new_path);
+ update_file(0, dst_other.sha1, dst_other.mode, new_path);
+ } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
+ ren2 = item->util;
+ clean_merge = 0;
+ ren2->processed = 1;
+ output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
+ "Renamed %s->%s in %s",
+ ren1_src, ren1_dst, branch1,
+ ren2->pair->one->path, ren2->pair->two->path, branch2);
+ conflict_rename_rename_2(ren1, branch1, ren2, branch2);
+ } else
+ try_merge = 1;
+
+ if (try_merge) {
+ struct diff_filespec *o, *a, *b;
+ struct merge_file_info mfi;
+ src_other.path = (char *)ren1_src;
+
+ o = ren1->pair->one;
+ if (a_renames == renames1) {
+ a = ren1->pair->two;
+ b = &src_other;
+ } else {
+ b = ren1->pair->two;
+ a = &src_other;
+ }
+ mfi = merge_file(o, a, b,
+ a_branch, b_branch);
+
+ if (mfi.clean &&
+ sha_eq(mfi.sha, ren1->pair->two->sha1) &&
+ mfi.mode == ren1->pair->two->mode)
+ /*
+ * This messaged is part of
+ * t6022 test. If you change
+ * it update the test too.
+ */
+ output(3, "Skipped %s (merged same as existing)", ren1_dst);
+ else {
+ if (mfi.merge || !mfi.clean)
+ output(1, "Renamed %s => %s", ren1_src, ren1_dst);
+ if (mfi.merge)
+ output(2, "Auto-merged %s", ren1_dst);
+ if (!mfi.clean) {
+ output(1, "CONFLICT (rename/modify): Merge conflict in %s",
+ ren1_dst);
+ clean_merge = 0;
+
+ if (!index_only)
+ update_stages(ren1_dst,
+ o, a, b, 1);
+ }
+ update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
+ }
+ }
+ }
+ }
+ path_list_clear(&a_by_dst, 0);
+ path_list_clear(&b_by_dst, 0);
+
+ return clean_merge;
+}
+
+static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
+{
+ return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
+}
+
+/* Per entry merge function */
+static int process_entry(const char *path, struct stage_data *entry,
+ const char *branch1,
+ const char *branch2)
+{
+ /*
+ printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
+ print_index_entry("\tpath: ", entry);
+ */
+ int clean_merge = 1;
+ unsigned o_mode = entry->stages[1].mode;
+ unsigned a_mode = entry->stages[2].mode;
+ unsigned b_mode = entry->stages[3].mode;
+ unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
+ unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
+ unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
+
+ if (o_sha && (!a_sha || !b_sha)) {
+ /* Case A: Deleted in one */
+ if ((!a_sha && !b_sha) ||
+ (sha_eq(a_sha, o_sha) && !b_sha) ||
+ (!a_sha && sha_eq(b_sha, o_sha))) {
+ /* Deleted in both or deleted in one and
+ * unchanged in the other */
+ if (a_sha)
+ output(2, "Removed %s", path);
+ /* do not touch working file if it did not exist */
+ remove_file(1, path, !a_sha);
+ } else {
+ /* Deleted in one and changed in the other */
+ clean_merge = 0;
+ if (!a_sha) {
+ output(1, "CONFLICT (delete/modify): %s deleted in %s "
+ "and modified in %s. Version %s of %s left in tree.",
+ path, branch1,
+ branch2, branch2, path);
+ update_file(0, b_sha, b_mode, path);
+ } else {
+ output(1, "CONFLICT (delete/modify): %s deleted in %s "
+ "and modified in %s. Version %s of %s left in tree.",
+ path, branch2,
+ branch1, branch1, path);
+ update_file(0, a_sha, a_mode, path);
+ }
+ }
+
+ } else if ((!o_sha && a_sha && !b_sha) ||
+ (!o_sha && !a_sha && b_sha)) {
+ /* Case B: Added in one. */
+ const char *add_branch;
+ const char *other_branch;
+ unsigned mode;
+ const unsigned char *sha;
+ const char *conf;
+
+ if (a_sha) {
+ add_branch = branch1;
+ other_branch = branch2;
+ mode = a_mode;
+ sha = a_sha;
+ conf = "file/directory";
+ } else {
+ add_branch = branch2;
+ other_branch = branch1;
+ mode = b_mode;
+ sha = b_sha;
+ conf = "directory/file";
+ }
+ if (path_list_has_path(&current_directory_set, path)) {
+ const char *new_path = unique_path(path, add_branch);
+ clean_merge = 0;
+ output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
+ "Added %s as %s",
+ conf, path, other_branch, path, new_path);
+ remove_file(0, path, 0);
+ update_file(0, sha, mode, new_path);
+ } else {
+ output(2, "Added %s", path);
+ update_file(1, sha, mode, path);
+ }
+ } else if (a_sha && b_sha) {
+ /* Case C: Added in both (check for same permissions) and */
+ /* case D: Modified in both, but differently. */
+ const char *reason = "content";
+ struct merge_file_info mfi;
+ struct diff_filespec o, a, b;
+
+ if (!o_sha) {
+ reason = "add/add";
+ o_sha = (unsigned char *)null_sha1;
+ }
+ output(2, "Auto-merged %s", path);
+ o.path = a.path = b.path = (char *)path;
+ hashcpy(o.sha1, o_sha);
+ o.mode = o_mode;
+ hashcpy(a.sha1, a_sha);
+ a.mode = a_mode;
+ hashcpy(b.sha1, b_sha);
+ b.mode = b_mode;
+
+ mfi = merge_file(&o, &a, &b,
+ branch1, branch2);
+
+ if (mfi.clean)
+ update_file(1, mfi.sha, mfi.mode, path);
+ else {
+ clean_merge = 0;
+ output(1, "CONFLICT (%s): Merge conflict in %s",
+ reason, path);
+
+ if (index_only)
+ update_file(0, mfi.sha, mfi.mode, path);
+ else
+ update_file_flags(mfi.sha, mfi.mode, path,
+ 0 /* update_cache */, 1 /* update_working_directory */);
+ }
+ } else if (!o_sha && !a_sha && !b_sha) {
+ /*
+ * this entry was deleted altogether. a_mode == 0 means
+ * we had that path and want to actively remove it.
+ */
+ remove_file(1, path, !a_mode);
+ } else
+ die("Fatal merge failure, shouldn't happen.");
+
+ return clean_merge;
+}
+
+static int merge_trees(struct tree *head,
+ struct tree *merge,
+ struct tree *common,
+ const char *branch1,
+ const char *branch2,
+ struct tree **result)
+{
+ int code, clean;
+
+ if (subtree_merge) {
+ merge = shift_tree_object(head, merge);
+ common = shift_tree_object(head, common);
+ }
+
+ if (sha_eq(common->object.sha1, merge->object.sha1)) {
+ output(0, "Already uptodate!");
+ *result = head;
+ return 1;
+ }
+
+ code = git_merge_trees(index_only, common, head, merge);
+
+ if (code != 0)
+ die("merging of trees %s and %s failed",
+ sha1_to_hex(head->object.sha1),
+ sha1_to_hex(merge->object.sha1));
+
+ if (unmerged_index()) {
+ struct path_list *entries, *re_head, *re_merge;
+ int i;
+ path_list_clear(&current_file_set, 1);
+ path_list_clear(&current_directory_set, 1);
+ get_files_dirs(head);
+ get_files_dirs(merge);
+
+ entries = get_unmerged();
+ re_head = get_renames(head, common, head, merge, entries);
+ re_merge = get_renames(merge, common, head, merge, entries);
+ clean = process_renames(re_head, re_merge,
+ branch1, branch2);
+ for (i = 0; i < entries->nr; i++) {
+ const char *path = entries->items[i].path;
+ struct stage_data *e = entries->items[i].util;
+ if (!e->processed
+ && !process_entry(path, e, branch1, branch2))
+ clean = 0;
+ }
+
+ path_list_clear(re_merge, 0);
+ path_list_clear(re_head, 0);
+ path_list_clear(entries, 1);
+
+ }
+ else
+ clean = 1;
+
+ if (index_only)
+ *result = git_write_tree();
+
+ return clean;
+}
+
+static struct commit_list *reverse_commit_list(struct commit_list *list)
+{
+ struct commit_list *next = NULL, *current, *backup;
+ for (current = list; current; current = backup) {
+ backup = current->next;
+ current->next = next;
+ next = current;
+ }
+ return next;
+}
+
+/*
+ * Merge the commits h1 and h2, return the resulting virtual
+ * commit object and a flag indicating the cleanness of the merge.
+ */
+static int merge(struct commit *h1,
+ struct commit *h2,
+ const char *branch1,
+ const char *branch2,
+ struct commit_list *ca,
+ struct commit **result)
+{
+ struct commit_list *iter;
+ struct commit *merged_common_ancestors;
+ struct tree *mrtree;
+ int clean;
+
+ if (show(4)) {
+ output(4, "Merging:");
+ output_commit_title(h1);
+ output_commit_title(h2);
+ }
+
+ if (!ca) {
+ ca = get_merge_bases(h1, h2, 1);
+ ca = reverse_commit_list(ca);
+ }
+
+ if (show(5)) {
+ output(5, "found %u common ancestor(s):", commit_list_count(ca));
+ for (iter = ca; iter; iter = iter->next)
+ output_commit_title(iter->item);
+ }
+
+ merged_common_ancestors = pop_commit(&ca);
+ if (merged_common_ancestors == NULL) {
+ /* if there is no common ancestor, make an empty tree */
+ 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);
+ merged_common_ancestors = make_virtual_commit(tree, "ancestor");
+ }
+
+ for (iter = ca; iter; iter = iter->next) {
+ call_depth++;
+ /*
+ * When the merge fails, the result contains files
+ * with conflict markers. The cleanness flag is
+ * ignored, it was never actually used, as result of
+ * merge_trees has always overwritten it: the committed
+ * "conflicts" were already resolved.
+ */
+ discard_cache();
+ merge(merged_common_ancestors, iter->item,
+ "Temporary merge branch 1",
+ "Temporary merge branch 2",
+ NULL,
+ &merged_common_ancestors);
+ call_depth--;
+
+ if (!merged_common_ancestors)
+ die("merge returned no commit");
+ }
+
+ discard_cache();
+ if (!call_depth) {
+ read_cache();
+ index_only = 0;
+ } else
+ index_only = 1;
+
+ clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
+ branch1, branch2, &mrtree);
+
+ if (index_only) {
+ *result = make_virtual_commit(mrtree, "merged tree");
+ commit_list_insert(h1, &(*result)->parents);
+ commit_list_insert(h2, &(*result)->parents->next);
+ }
+ flush_output();
+ return clean;
+}
+
+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;
+}
+
+static struct commit *get_ref(const char *ref)
+{
+ unsigned char sha1[20];
+ struct object *object;
+
+ if (get_sha1(ref, sha1))
+ die("Could not resolve ref '%s'", ref);
+ object = deref_tag(parse_object(sha1), ref, strlen(ref));
+ if (object->type == OBJ_TREE)
+ return make_virtual_commit((struct tree*)object,
+ better_branch_name(ref));
+ if (object->type != OBJ_COMMIT)
+ return NULL;
+ if (parse_commit((struct commit *)object))
+ die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
+ return (struct commit *)object;
+}
+
+static int merge_config(const char *var, const char *value)
+{
+ if (!strcasecmp(var, "merge.verbosity")) {
+ verbosity = git_config_int(var, value);
+ return 0;
+ }
+ return git_default_config(var, value);
+}
+
+int main(int argc, char *argv[])
+{
+ static const char *bases[20];
+ static unsigned bases_count = 0;
+ int i, clean;
+ const char *branch1, *branch2;
+ struct commit *result, *h1, *h2;
+ struct commit_list *ca = NULL;
+ struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+ int index_fd;
+
+ if (argv[0]) {
+ int namelen = strlen(argv[0]);
+ if (8 < namelen &&
+ !strcmp(argv[0] + namelen - 8, "-subtree"))
+ subtree_merge = 1;
+ }
+
+ git_config(merge_config);
+ if (getenv("GIT_MERGE_VERBOSITY"))
+ verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
+
+ if (argc < 4)
+ die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
+
+ for (i = 1; i < argc; ++i) {
+ if (!strcmp(argv[i], "--"))
+ break;
+ if (bases_count < sizeof(bases)/sizeof(*bases))
+ bases[bases_count++] = argv[i];
+ }
+ if (argc - i != 3) /* "--" "<head>" "<remote>" */
+ die("Not handling anything other than two heads merge.");
+ if (verbosity >= 5)
+ buffer_output = 0;
+
+ branch1 = argv[++i];
+ branch2 = argv[++i];
+
+ h1 = get_ref(branch1);
+ h2 = get_ref(branch2);
+
+ branch1 = better_branch_name(branch1);
+ branch2 = better_branch_name(branch2);
+
+ if (show(3))
+ printf("Merging %s with %s\n", branch1, branch2);
+
+ index_fd = hold_locked_index(lock, 1);
+
+ for (i = 0; i < bases_count; i++) {
+ struct commit *ancestor = get_ref(bases[i]);
+ ca = commit_list_insert(ancestor, &ca);
+ }
+ clean = merge(h1, h2, branch1, branch2, ca, &result);
+
+ if (active_cache_changed &&
+ (write_cache(index_fd, active_cache, active_nr) ||
+ close(index_fd) || commit_locked_index(lock)))
+ die ("unable to write %s", get_index_file());
+
+ return clean ? 0: 1;
+}