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authorJohannes Schindelin <Johannes.Schindelin@gmx.de>2006-07-08 16:42:41 (GMT)
committerJunio C Hamano <junkio@cox.net>2006-07-14 06:10:19 (GMT)
commit6d297f81373e19d86b8f02cb68120201d1b0ab1d (patch)
treef036ee3b98ce1a260895d8d3bec4889189dabafe /merge-recursive.c
parent4b7ce6e2d6ba088da50de1df38b040ea2c0b8f18 (diff)
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Status update on merge-recursive in C
This is just an update for people being interested. Alex and me were busy with that project for a few days now. While it has progressed nicely, there are quite a couple TODOs in merge-recursive.c, just search for "TODO". For impatient people: yes, it passes all the tests, and yes, according to the evil test Alex did, it is faster than the Python script. But no, it is not yet finished. Biggest points are: - there are still three external calls - in the end, it should not be necessary to write the index more than once (just before exiting) - a lot of things can be refactored to make the code easier and shorter BTW we cannot just plug in git-merge-tree yet, because git-merge-tree does not handle renames at all. This patch is meant for testing, and as such, - it compile the program to git-merge-recur - it adjusts the scripts and tests to use git-merge-recur instead of git-merge-recursive - it provides "TEST", a script to execute the tests regarding -recursive - it inlines the changes to read-cache.c (read_cache_from(), discard_cache() and refresh_cache_entry()) Brought to you by Alex Riesen and Dscho Signed-off-by: Junio C Hamano <junkio@cox.net>
Diffstat (limited to 'merge-recursive.c')
-rw-r--r--merge-recursive.c1560
1 files changed, 1560 insertions, 0 deletions
diff --git a/merge-recursive.c b/merge-recursive.c
new file mode 100644
index 0000000..cf81768
--- /dev/null
+++ b/merge-recursive.c
@@ -0,0 +1,1560 @@
+/*
+ * 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 <stdarg.h>
+#include <string.h>
+#include <assert.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <time.h>
+#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 "path-list.h"
+
+/*#define DEBUG*/
+
+#ifdef DEBUG
+#define debug(args, ...) fprintf(stderr, args, ## __VA_ARGS__)
+#else
+#define debug(args, ...)
+#endif
+
+#ifdef DEBUG
+#include "quote.h"
+static void show_ce_entry(const char *tag, struct cache_entry *ce)
+{
+ if (tag && *tag &&
+ (ce->ce_flags & htons(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;
+ }
+
+ fprintf(stderr,"%s%06o %s %d\t",
+ tag,
+ ntohl(ce->ce_mode),
+ sha1_to_hex(ce->sha1),
+ ce_stage(ce));
+ write_name_quoted("", 0, ce->name,
+ '\n', stderr);
+ fputc('\n', stderr);
+}
+
+static void ls_files() {
+ int i;
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ show_ce_entry("", ce);
+ }
+ fprintf(stderr, "---\n");
+}
+#endif
+
+/*
+ * A virtual commit has
+ * - (const char *)commit->util set to the name, and
+ * - *(int *)commit->object.sha1 set to the virtual id.
+ */
+static const char *commit_title(struct commit *commit, int *len)
+{
+ const char *s = "(null commit)";
+ *len = strlen(s);
+
+ if ( commit->util ) {
+ s = commit->util;
+ *len = strlen(s);
+ } else {
+ if ( parse_commit(commit) != 0 ) {
+ s = "(bad commit)";
+ *len = strlen(s);
+ } else {
+ s = commit->buffer;
+ char prev = '\0';
+ while ( *s ) {
+ if ( '\n' == prev && '\n' == *s ) {
+ ++s;
+ break;
+ }
+ prev = *s++;
+ }
+ *len = 0;
+ while ( s[*len] && '\n' != s[*len] )
+ ++(*len);
+ }
+ }
+ return s;
+}
+
+static const char *commit_hex_sha1(const struct commit *commit)
+{
+ return commit->util ? "virtual" : commit ?
+ sha1_to_hex(commit->object.sha1) : "undefined";
+}
+
+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++;
+ return commit;
+}
+
+/*
+ * TODO: we should not have to copy the SHA1s around, but rather reference
+ * them. That way, sha_eq() is just sha1 == sha2.
+ */
+static int sha_eq(const unsigned char *a, const unsigned char *b)
+{
+ if ( !a && !b )
+ return 2;
+ return a && b && memcmp(a, b, 20) == 0;
+}
+
+static void memswp(void *p1, void *p2, unsigned n)
+{
+ unsigned char *a = p1, *b = p2;
+ while ( n-- ) {
+ *a ^= *b;
+ *b ^= *a;
+ *a ^= *b;
+ ++a;
+ ++b;
+ }
+}
+
+/*
+ * TODO: we should convert the merge_result users to
+ * int blabla(..., struct commit **result)
+ * like everywhere else in git.
+ * Same goes for merge_tree_result and merge_file_info.
+ */
+struct merge_result
+{
+ struct commit *commit;
+ unsigned clean:1;
+};
+
+struct merge_tree_result
+{
+ struct tree *tree;
+ unsigned clean:1;
+};
+
+/*
+ * TODO: check if we can just reuse the active_cache structure: it is already
+ * sorted (by name, stage).
+ * Only problem: do not write it when flushing the cache.
+ */
+struct stage_data
+{
+ struct
+ {
+ unsigned mode;
+ unsigned char sha[20];
+ } stages[4];
+ unsigned processed:1;
+};
+
+static struct path_list currentFileSet = {NULL, 0, 0, 1};
+static struct path_list currentDirectorySet = {NULL, 0, 0, 1};
+
+static int output_indent = 0;
+
+static void output(const char *fmt, ...)
+{
+ va_list args;
+ int i;
+ for ( i = output_indent; i--; )
+ fputs(" ", stdout);
+ va_start(args, fmt);
+ vfprintf(stdout, fmt, args);
+ va_end(args);
+ fputc('\n', stdout);
+}
+
+static const char *original_index_file;
+static const char *temporary_index_file;
+static int cache_dirty = 0;
+
+static int flush_cache()
+{
+ /* flush temporary index */
+ struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+ int fd = hold_lock_file_for_update(lock, getenv("GIT_INDEX_FILE"));
+ if (fd < 0)
+ die("could not lock %s", temporary_index_file);
+ if (write_cache(fd, active_cache, active_nr) ||
+ close(fd) || commit_lock_file(lock))
+ die ("unable to write %s", getenv("GIT_INDEX_FILE"));
+ discard_cache();
+ cache_dirty = 0;
+ return 0;
+}
+
+static void setup_index(int temp)
+{
+ const char *idx = temp ? temporary_index_file: original_index_file;
+ if (cache_dirty)
+ die("fatal: cache changed flush_cache();");
+ unlink(temporary_index_file);
+ setenv("GIT_INDEX_FILE", idx, 1);
+ discard_cache();
+}
+
+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);
+
+ memcpy(ce->sha1, sha1, 20);
+ 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;
+ if (!cache_dirty)
+ read_cache_from(getenv("GIT_INDEX_FILE"));
+ cache_dirty++;
+ ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
+ if (!ce)
+ return error("cache_addinfo failed: %s", strerror(cache_errno));
+ 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;
+
+/*
+ * TODO: this can be streamlined by refactoring builtin-read-tree.c
+ */
+static int git_read_tree(const struct tree *tree)
+{
+#if 0
+ fprintf(stderr, "GIT_INDEX_FILE='%s' git-read-tree %s\n",
+ getenv("GIT_INDEX_FILE"),
+ sha1_to_hex(tree->object.sha1));
+#endif
+ const char *argv[] = { "git-read-tree", NULL, NULL, };
+ if (cache_dirty)
+ die("read-tree with dirty cache");
+ argv[1] = sha1_to_hex(tree->object.sha1);
+ int rc = run_command_v(2, argv);
+ return rc < 0 ? -1: rc;
+}
+
+/*
+ * TODO: this can be streamlined by refactoring builtin-read-tree.c
+ */
+static int git_merge_trees(const char *update_arg,
+ struct tree *common,
+ struct tree *head,
+ struct tree *merge)
+{
+#if 0
+ fprintf(stderr, "GIT_INDEX_FILE='%s' git-read-tree %s -m %s %s %s\n",
+ getenv("GIT_INDEX_FILE"),
+ update_arg,
+ sha1_to_hex(common->object.sha1),
+ sha1_to_hex(head->object.sha1),
+ sha1_to_hex(merge->object.sha1));
+#endif
+ const char *argv[] = {
+ "git-read-tree", NULL, "-m", NULL, NULL, NULL,
+ NULL,
+ };
+ if (cache_dirty)
+ flush_cache();
+ argv[1] = update_arg;
+ argv[3] = sha1_to_hex(common->object.sha1);
+ argv[4] = sha1_to_hex(head->object.sha1);
+ argv[5] = sha1_to_hex(merge->object.sha1);
+ int rc = run_command_v(6, argv);
+ return rc < 0 ? -1: rc;
+}
+
+/*
+ * TODO: this can be streamlined by refactoring builtin-write-tree.c
+ */
+static struct tree *git_write_tree()
+{
+#if 0
+ fprintf(stderr, "GIT_INDEX_FILE='%s' git-write-tree\n",
+ getenv("GIT_INDEX_FILE"));
+#endif
+ if (cache_dirty)
+ flush_cache();
+ FILE *fp = popen("git-write-tree 2>/dev/null", "r");
+ char buf[41];
+ unsigned char sha1[20];
+ int ch;
+ unsigned i = 0;
+ while ( (ch = fgetc(fp)) != EOF )
+ if ( i < sizeof(buf)-1 && ch >= '0' && ch <= 'f' )
+ buf[i++] = ch;
+ else
+ break;
+ int rc = pclose(fp);
+ if ( rc == -1 || WEXITSTATUS(rc) )
+ return NULL;
+ buf[i] = '\0';
+ if ( get_sha1(buf, sha1) != 0 )
+ return NULL;
+ return lookup_tree(sha1);
+}
+
+/*
+ * TODO: get rid of files_and_dirs; we do not use it except for
+ * current_file_set and current_dir_set, which are global already.
+ */
+static struct
+{
+ struct path_list *files;
+ struct path_list *dirs;
+} files_and_dirs;
+
+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 = malloc(baselen + len + 1);
+ memcpy(newpath, base, baselen);
+ memcpy(newpath + baselen, path, len);
+ newpath[baselen + len] = '\0';
+
+ if (S_ISDIR(mode))
+ path_list_insert(newpath, files_and_dirs.dirs);
+ else
+ path_list_insert(newpath, files_and_dirs.files);
+ free(newpath);
+
+ return READ_TREE_RECURSIVE;
+}
+
+static int get_files_dirs(struct tree *tree,
+ struct path_list *files,
+ struct path_list *dirs)
+{
+ int n;
+ files_and_dirs.files = files;
+ files_and_dirs.dirs = dirs;
+ debug("get_files_dirs ...\n");
+ if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0) {
+ debug(" get_files_dirs done (0)\n");
+ return 0;
+ }
+ n = files->nr + dirs->nr;
+ debug(" get_files_dirs done (%d)\n", n);
+ return n;
+}
+
+/*
+ * TODO: this wrapper is so small, we can use path_list_lookup directly.
+ * Same goes for index_entry_get(), free_index_entries(), find_rename_bysrc(),
+ * free_rename_entries().
+ */
+static struct stage_data *index_entry_find(struct path_list *ents,
+ const char *path)
+{
+ struct path_list_item *item = path_list_lookup(path, ents);
+ if (item)
+ return item->util;
+ return NULL;
+}
+
+static struct stage_data *index_entry_get(struct path_list *ents,
+ const char *path)
+{
+ struct path_list_item *item = path_list_lookup(path, ents);
+
+ if (item == NULL) {
+ item = path_list_insert(path, ents);
+ item->util = xcalloc(1, sizeof(struct stage_data));
+ }
+ return item->util;
+}
+
+/*
+ * TODO: since the result of index_entry_from_db() is tucked into a
+ * path_list anyway, this helper can do that already.
+ */
+/*
+ * Returns a index_entry instance which doesn't have to correspond to
+ * a real cache entry in Git's index.
+ */
+static struct stage_data *index_entry_from_db(const char *path,
+ struct tree *o,
+ struct tree *a,
+ struct tree *b)
+{
+ 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);
+ return e;
+}
+
+static void free_index_entries(struct path_list **ents)
+{
+ if (!*ents)
+ return;
+
+ path_list_clear(*ents, 1);
+ free(*ents);
+ *ents = NULL;
+}
+
+/*
+ * Create a dictionary mapping file names to CacheEntry objects. The
+ * dictionary contains one entry for every path with a non-zero stage entry.
+ */
+static struct path_list *get_unmerged()
+{
+ struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
+ int i;
+
+ unmerged->strdup_paths = 1;
+ if (!cache_dirty) {
+ read_cache_from(getenv("GIT_INDEX_FILE"));
+ cache_dirty++;
+ }
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ if (!ce_stage(ce))
+ continue;
+
+ struct stage_data *e = index_entry_get(unmerged, ce->name);
+ e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
+ memcpy(e->stages[ce_stage(ce)].sha, ce->sha1, 20);
+ }
+
+ debug(" get_unmerged done\n");
+ return unmerged;
+}
+
+struct rename
+{
+ struct diff_filepair *pair;
+ struct stage_data *src_entry;
+ struct stage_data *dst_entry;
+ unsigned processed:1;
+};
+
+static struct rename *find_rename_bysrc(struct path_list *e,
+ const char *name)
+{
+ struct path_list_item *item = path_list_lookup(name, e);
+ if (item)
+ return item->util;
+ return NULL;
+}
+
+static void free_rename_entries(struct path_list **list)
+{
+ if (!*list)
+ return;
+
+ path_list_clear(*list, 0);
+ free(*list);
+ *list = NULL;
+}
+
+/*
+ * Get information of all renames which occured between 'oTree' and
+ * 'tree'. We need the three trees in the merge ('oTree', 'aTree' and
+ * 'bTree') to be able to associate the correct cache entries with
+ * the rename information. 'tree' is always equal to either aTree or bTree.
+ */
+static struct path_list *get_renames(struct tree *tree,
+ struct tree *oTree,
+ struct tree *aTree,
+ struct tree *bTree,
+ struct path_list *entries)
+{
+#ifdef DEBUG
+ time_t t = time(0);
+ debug("getRenames ...\n");
+#endif
+ int i;
+ struct path_list *renames = xcalloc(1, sizeof(struct path_list));
+ struct diff_options opts;
+ 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(oTree->object.sha1, tree->object.sha1, "", &opts);
+ diffcore_std(&opts);
+ for (i = 0; i < diff_queued_diff.nr; ++i) {
+ 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;
+ re->src_entry = index_entry_find(entries, re->pair->one->path);
+ /* TODO: should it not be an error, if src_entry was found? */
+ if ( !re->src_entry ) {
+ re->src_entry = index_entry_from_db(re->pair->one->path,
+ oTree, aTree, bTree);
+ struct path_list_item *item =
+ path_list_insert(re->pair->one->path, entries);
+ item->util = re->src_entry;
+ }
+ re->dst_entry = index_entry_find(entries, re->pair->two->path);
+ if ( !re->dst_entry ) {
+ re->dst_entry = index_entry_from_db(re->pair->two->path,
+ oTree, aTree, bTree);
+ struct path_list_item *item =
+ path_list_insert(re->pair->two->path, entries);
+ item->util = re->dst_entry;
+ }
+ struct path_list_item *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);
+ debug(" getRenames done in %ld\n", time(0)-t);
+ return renames;
+}
+
+/*
+ * TODO: the code would be way nicer, if we had a struct containing just sha1 and mode.
+ * In this particular case, we might get away reusing stage_data, no?
+ */
+int update_stages(const char *path,
+ unsigned char *osha, unsigned omode,
+ unsigned char *asha, unsigned amode,
+ unsigned char *bsha, unsigned bmode,
+ int clear /* =True */)
+{
+ int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
+ if ( clear )
+ if (add_cacheinfo(0, null_sha1, path, 0, 0, options))
+ return -1;
+ if ( omode )
+ if (add_cacheinfo(omode, osha, path, 1, 0, options))
+ return -1;
+ if ( amode )
+ if (add_cacheinfo(omode, osha, path, 2, 0, options))
+ return -1;
+ if ( bmode )
+ if (add_cacheinfo(omode, osha, path, 3, 0, options))
+ return -1;
+ return 0;
+}
+
+/*
+ * TODO: there has to be a function in libgit doing this exact thing.
+ */
+static int remove_path(const char *name)
+{
+ int ret;
+ char *slash;
+
+ ret = unlink(name);
+ if ( ret )
+ return ret;
+ int len = strlen(name);
+ char *dirs = malloc(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;
+}
+
+/* General TODO: unC99ify the code: no declaration after code */
+/* General TODO: no javaIfiCation: rename updateCache to update_cache */
+/*
+ * TODO: once we no longer call external programs, we'd probably be better of
+ * not setting / getting the environment variable GIT_INDEX_FILE all the time.
+ */
+int remove_file(int clean, const char *path)
+{
+ int updateCache = index_only || clean;
+ int updateWd = !index_only;
+
+ if ( updateCache ) {
+ if (!cache_dirty)
+ read_cache_from(getenv("GIT_INDEX_FILE"));
+ cache_dirty++;
+ if (remove_file_from_cache(path))
+ return -1;
+ }
+ if ( updateWd )
+ {
+ 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);
+ strcpy(newpath, path);
+ strcat(newpath, "~");
+ char *p = newpath + strlen(newpath);
+ strcpy(p, branch);
+ for ( ; *p; ++p )
+ if ( '/' == *p )
+ *p = '_';
+ int suffix = 0;
+ struct stat st;
+ while ( path_list_has_path(&currentFileSet, newpath) ||
+ path_list_has_path(&currentDirectorySet, newpath) ||
+ lstat(newpath, &st) == 0 ) {
+ sprintf(p, "_%d", suffix++);
+ }
+ path_list_insert(newpath, &currentFileSet);
+ return newpath;
+}
+
+/*
+ * TODO: except for create_last, this so looks like
+ * safe_create_leading_directories().
+ */
+static int mkdir_p(const char *path, unsigned long mode, int create_last)
+{
+ char *buf = strdup(path);
+ char *p;
+
+ for ( p = buf; *p; ++p ) {
+ if ( *p != '/' )
+ continue;
+ *p = '\0';
+ if (mkdir(buf, mode)) {
+ int e = errno;
+ if ( e == EEXIST ) {
+ struct stat st;
+ if ( !stat(buf, &st) && S_ISDIR(st.st_mode) )
+ goto next; /* ok */
+ errno = e;
+ }
+ free(buf);
+ return -1;
+ }
+ next:
+ *p = '/';
+ }
+ free(buf);
+ if ( create_last && mkdir(path, mode) )
+ return -1;
+ return 0;
+}
+
+static void flush_buffer(int fd, const char *buf, unsigned long size)
+{
+ while (size > 0) {
+ long ret = xwrite(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;
+ }
+}
+
+/* General TODO: reindent according to guide lines (no if ( blabla )) */
+void update_file_flags(const unsigned char *sha,
+ unsigned mode,
+ const char *path,
+ int updateCache,
+ int updateWd)
+{
+ if ( index_only )
+ updateWd = 0;
+
+ if ( updateWd ) {
+ char type[20];
+ 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 ( strcmp(type, blob_type) != 0 )
+ die("blob expected for %s '%s'", sha1_to_hex(sha), path);
+
+ if ( S_ISREG(mode) ) {
+ if ( mkdir_p(path, 0777, 0 /* don't create last element */) )
+ die("failed to create path %s: %s", path, strerror(errno));
+ unlink(path);
+ if ( mode & 0100 )
+ mode = 0777;
+ else
+ mode = 0666;
+ int 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 *linkTarget = malloc(size + 1);
+ memcpy(linkTarget, buf, size);
+ linkTarget[size] = '\0';
+ mkdir_p(path, 0777, 0);
+ symlink(linkTarget, path);
+ } else
+ die("do not know what to do with %06o %s '%s'",
+ mode, sha1_to_hex(sha), path);
+ }
+ if ( updateCache )
+ add_cacheinfo(mode, sha, path, 0, updateWd, ADD_CACHE_OK_TO_ADD);
+}
+
+/* TODO: is this often used? if not, do direct call */
+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 char *git_unpack_file(const unsigned char *sha1, char *path)
+{
+ void *buf;
+ char type[20];
+ unsigned long size;
+ int fd;
+
+ buf = read_sha1_file(sha1, type, &size);
+ if (!buf || strcmp(type, blob_type))
+ die("unable to read blob object %s", sha1_to_hex(sha1));
+
+ strcpy(path, ".merge_file_XXXXXX");
+ fd = mkstemp(path);
+ if (fd < 0)
+ die("unable to create temp-file");
+ flush_buffer(fd, buf, size);
+ close(fd);
+ return path;
+}
+
+/*
+ * TODO: the signature would be much more efficient using stage_data
+ */
+static struct merge_file_info merge_file(const char *oPath,
+ const unsigned char *oSha,
+ unsigned oMode,
+ const char *aPath,
+ const unsigned char *aSha,
+ unsigned aMode,
+ const char *bPath,
+ const unsigned char *bSha,
+ unsigned bMode,
+ const char *branch1Name,
+ const char *branch2Name)
+{
+ struct merge_file_info result;
+ result.merge = 0;
+ result.clean = 1;
+
+ if ( (S_IFMT & aMode) != (S_IFMT & bMode) ) {
+ result.clean = 0;
+ if ( S_ISREG(aMode) ) {
+ result.mode = aMode;
+ memcpy(result.sha, aSha, 20);
+ } else {
+ result.mode = bMode;
+ memcpy(result.sha, bSha, 20);
+ }
+ } else {
+ if ( memcmp(aSha, oSha, 20) != 0 && memcmp(bSha, oSha, 20) != 0 )
+ result.merge = 1;
+
+ result.mode = aMode == oMode ? bMode: aMode;
+
+ if ( memcmp(aSha, oSha, 20) == 0 )
+ memcpy(result.sha, bSha, 20);
+ else if ( memcmp(bSha, oSha, 20) == 0 )
+ memcpy(result.sha, aSha, 20);
+ else if ( S_ISREG(aMode) ) {
+
+ int code = 1;
+ char orig[PATH_MAX];
+ char src1[PATH_MAX];
+ char src2[PATH_MAX];
+
+ git_unpack_file(oSha, orig);
+ git_unpack_file(aSha, src1);
+ git_unpack_file(bSha, src2);
+
+ const char *argv[] = {
+ "merge", "-L", NULL, "-L", NULL, "-L", NULL,
+ src1, orig, src2,
+ NULL
+ };
+ char *la, *lb, *lo;
+ argv[2] = la = strdup(mkpath("%s/%s", branch1Name, aPath));
+ argv[6] = lb = strdup(mkpath("%s/%s", branch2Name, bPath));
+ argv[4] = lo = strdup(mkpath("orig/%s", oPath));
+
+#if 0
+ printf("%s %s %s %s %s %s %s %s %s %s\n",
+ argv[0], argv[1], argv[2], argv[3], argv[4],
+ argv[5], argv[6], argv[7], argv[8], argv[9]);
+#endif
+ code = run_command_v(10, argv);
+
+ free(la);
+ free(lb);
+ free(lo);
+ if ( code && code < -256 ) {
+ die("Failed to execute 'merge'. merge(1) is used as the "
+ "file-level merge tool. Is 'merge' in your path?");
+ }
+ struct stat st;
+ int fd = open(src1, O_RDONLY);
+ if (fd < 0 || fstat(fd, &st) < 0 ||
+ index_fd(result.sha, fd, &st, 1,
+ "blob"))
+ die("Unable to add %s to database", src1);
+ close(fd);
+
+ unlink(orig);
+ unlink(src1);
+ unlink(src2);
+
+ result.clean = WEXITSTATUS(code) == 0;
+ } else {
+ if ( !(S_ISLNK(aMode) || S_ISLNK(bMode)) )
+ die("cannot merge modes?");
+
+ memcpy(result.sha, aSha, 20);
+
+ if ( memcmp(aSha, bSha, 20) != 0 )
+ 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 *dstName1 = ren1_dst;
+ const char *dstName2 = ren2_dst;
+ if (path_list_has_path(&currentDirectorySet, ren1_dst)) {
+ dstName1 = del[delp++] = unique_path(ren1_dst, branch1);
+ output("%s is a directory in %s adding as %s instead",
+ ren1_dst, branch2, dstName1);
+ remove_file(0, ren1_dst);
+ }
+ if (path_list_has_path(&currentDirectorySet, ren2_dst)) {
+ dstName2 = del[delp++] = unique_path(ren2_dst, branch2);
+ output("%s is a directory in %s adding as %s instead",
+ ren2_dst, branch1, dstName2);
+ remove_file(0, ren2_dst);
+ }
+ update_stages(dstName1,
+ NULL, 0,
+ ren1->pair->two->sha1, ren1->pair->two->mode,
+ NULL, 0,
+ 1 /* clear */);
+ update_stages(dstName2,
+ NULL, 0,
+ NULL, 0,
+ ren2->pair->two->sha1, ren2->pair->two->mode,
+ 1 /* clear */);
+ while ( delp-- )
+ free(del[delp]);
+}
+
+static void conflict_rename_dir(struct rename *ren1,
+ const char *branch1)
+{
+ char *newPath = unique_path(ren1->pair->two->path, branch1);
+ output("Renaming %s to %s instead", ren1->pair->one->path, newPath);
+ remove_file(0, ren1->pair->two->path);
+ update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, newPath);
+ free(newPath);
+}
+
+static void conflict_rename_rename_2(struct rename *ren1,
+ const char *branch1,
+ struct rename *ren2,
+ const char *branch2)
+{
+ char *newPath1 = unique_path(ren1->pair->two->path, branch1);
+ char *newPath2 = unique_path(ren2->pair->two->path, branch2);
+ output("Renaming %s to %s and %s to %s instead",
+ ren1->pair->one->path, newPath1,
+ ren2->pair->one->path, newPath2);
+ remove_file(0, ren1->pair->two->path);
+ update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, newPath1);
+ update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, newPath2);
+ free(newPath2);
+ free(newPath1);
+}
+
+/* General TODO: get rid of all the debug messages */
+static int process_renames(struct path_list *renamesA,
+ struct path_list *renamesB,
+ const char *branchNameA,
+ const char *branchNameB)
+{
+ int cleanMerge = 1, i;
+ struct path_list srcNames = {NULL, 0, 0, 0}, byDstA = {NULL, 0, 0, 0}, byDstB = {NULL, 0, 0, 0};
+ const struct rename *sre;
+
+ /*
+ * TODO: think about a saner way to do this.
+ * Since both renamesA and renamesB are sorted, it should
+ * be much more efficient to traverse both simultaneously,
+ * only byDstA and byDstB should be needed.
+ */
+ debug("processRenames...\n");
+ for (i = 0; i < renamesA->nr; i++) {
+ sre = renamesA->items[i].util;
+ path_list_insert(sre->pair->one->path, &srcNames);
+ path_list_insert(sre->pair->two->path, &byDstA)->util
+ = sre->dst_entry;
+ }
+ for (i = 0; i < renamesB->nr; i++) {
+ sre = renamesB->items[i].util;
+ path_list_insert(sre->pair->one->path, &srcNames);
+ path_list_insert(sre->pair->two->path, &byDstB)->util
+ = sre->dst_entry;
+ }
+
+ for (i = 0; i < srcNames.nr; i++) {
+ char *src = srcNames.items[i].path;
+ struct path_list *renames1, *renames2, *renames2Dst;
+ struct rename *ren1, *ren2;
+ const char *branchName1, *branchName2;
+ ren1 = find_rename_bysrc(renamesA, src);
+ ren2 = find_rename_bysrc(renamesB, src);
+ /* TODO: refactor, so that 1/2 are not needed */
+ if ( ren1 ) {
+ renames1 = renamesA;
+ renames2 = renamesB;
+ renames2Dst = &byDstB;
+ branchName1 = branchNameA;
+ branchName2 = branchNameB;
+ } else {
+ renames1 = renamesB;
+ renames2 = renamesA;
+ renames2Dst = &byDstA;
+ branchName1 = branchNameB;
+ branchName2 = branchNameA;
+ struct rename *tmp = ren2;
+ ren2 = ren1;
+ ren1 = tmp;
+ }
+
+ ren1->dst_entry->processed = 1;
+ ren1->src_entry->processed = 1;
+
+ if ( ren1->processed )
+ continue;
+ ren1->processed = 1;
+
+ const char *ren1_src = ren1->pair->one->path;
+ const char *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) {
+ cleanMerge = 0;
+ output("CONFLICT (rename/rename): "
+ "Rename %s->%s in branch %s "
+ "rename %s->%s in %s",
+ src, ren1_dst, branchName1,
+ src, ren2_dst, branchName2);
+ conflict_rename_rename(ren1, branchName1, ren2, branchName2);
+ } else {
+ remove_file(1, ren1_src);
+ struct merge_file_info mfi;
+ mfi = merge_file(ren1_src,
+ ren1->pair->one->sha1,
+ ren1->pair->one->mode,
+ ren1_dst,
+ ren1->pair->two->sha1,
+ ren1->pair->two->mode,
+ ren2_dst,
+ ren2->pair->two->sha1,
+ ren2->pair->two->mode,
+ branchName1,
+ branchName2);
+ if ( mfi.merge || !mfi.clean )
+ output("Renaming %s->%s", src, ren1_dst);
+
+ if ( mfi.merge )
+ output("Auto-merging %s", ren1_dst);
+
+ if ( !mfi.clean ) {
+ output("CONFLICT (content): merge conflict in %s",
+ ren1_dst);
+ cleanMerge = 0;
+
+ if ( !index_only )
+ update_stages(ren1_dst,
+ ren1->pair->one->sha1,
+ ren1->pair->one->mode,
+ ren1->pair->two->sha1,
+ ren1->pair->two->mode,
+ ren2->pair->two->sha1,
+ ren2->pair->two->mode,
+ 1 /* clear */);
+ }
+ update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
+ }
+ } else {
+ /* Renamed in 1, maybe changed in 2 */
+ remove_file(1, ren1_src);
+
+ unsigned char srcShaOtherBranch[20], dstShaOtherBranch[20];
+ unsigned srcModeOtherBranch, dstModeOtherBranch;
+
+ int stage = renamesA == renames1 ? 3: 2;
+
+ memcpy(srcShaOtherBranch, ren1->src_entry->stages[stage].sha, 20);
+ srcModeOtherBranch = ren1->src_entry->stages[stage].mode;
+
+ memcpy(dstShaOtherBranch, ren1->dst_entry->stages[stage].sha, 20);
+ dstModeOtherBranch = ren1->dst_entry->stages[stage].mode;
+
+ int tryMerge = 0;
+ char *newPath;
+
+ if (path_list_has_path(&currentDirectorySet, ren1_dst)) {
+ cleanMerge = 0;
+ output("CONFLICT (rename/directory): Rename %s->%s in %s "
+ " directory %s added in %s",
+ ren1_src, ren1_dst, branchName1,
+ ren1_dst, branchName2);
+ conflict_rename_dir(ren1, branchName1);
+ } else if ( memcmp(srcShaOtherBranch, null_sha1, 20) == 0 ) {
+ cleanMerge = 0;
+ output("CONFLICT (rename/delete): Rename %s->%s in %s "
+ "and deleted in %s",
+ ren1_src, ren1_dst, branchName1,
+ branchName2);
+ update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
+ } else if ( memcmp(dstShaOtherBranch, null_sha1, 20) != 0 ) {
+ cleanMerge = 0;
+ tryMerge = 1;
+ output("CONFLICT (rename/add): Rename %s->%s in %s. "
+ "%s added in %s",
+ ren1_src, ren1_dst, branchName1,
+ ren1_dst, branchName2);
+ newPath = unique_path(ren1_dst, branchName2);
+ output("Adding as %s instead", newPath);
+ update_file(0, dstShaOtherBranch, dstModeOtherBranch, newPath);
+ } else if ( (ren2 = find_rename_bysrc(renames2Dst, ren1_dst)) ) {
+ cleanMerge = 0;
+ ren2->processed = 1;
+ output("CONFLICT (rename/rename): Rename %s->%s in %s. "
+ "Rename %s->%s in %s",
+ ren1_src, ren1_dst, branchName1,
+ ren2->pair->one->path, ren2->pair->two->path, branchName2);
+ conflict_rename_rename_2(ren1, branchName1, ren2, branchName2);
+ } else
+ tryMerge = 1;
+
+ if ( tryMerge ) {
+ const char *oname = ren1_src;
+ const char *aname = ren1_dst;
+ const char *bname = ren1_src;
+ unsigned char osha[20], asha[20], bsha[20];
+ unsigned omode = ren1->pair->one->mode;
+ unsigned amode = ren1->pair->two->mode;
+ unsigned bmode = srcModeOtherBranch;
+ memcpy(osha, ren1->pair->one->sha1, 20);
+ memcpy(asha, ren1->pair->two->sha1, 20);
+ memcpy(bsha, srcShaOtherBranch, 20);
+ const char *aBranch = branchName1;
+ const char *bBranch = branchName2;
+
+ if ( renamesA != renames1 ) {
+ memswp(&aname, &bname, sizeof(aname));
+ memswp(asha, bsha, 20);
+ memswp(&aBranch, &bBranch, sizeof(aBranch));
+ }
+ struct merge_file_info mfi;
+ mfi = merge_file(oname, osha, omode,
+ aname, asha, amode,
+ bname, bsha, bmode,
+ aBranch, bBranch);
+
+ if ( mfi.merge || !mfi.clean )
+ output("Renaming %s => %s", ren1_src, ren1_dst);
+ if ( mfi.merge )
+ output("Auto-merging %s", ren1_dst);
+ if ( !mfi.clean ) {
+ output("CONFLICT (rename/modify): Merge conflict in %s",
+ ren1_dst);
+ cleanMerge = 0;
+
+ if ( !index_only )
+ update_stages(ren1_dst,
+ osha, omode,
+ asha, amode,
+ bsha, bmode,
+ 1 /* clear */);
+ }
+ update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
+ }
+ }
+ }
+ path_list_clear(&srcNames, 0);
+ debug(" processRenames done\n");
+
+ if (cache_dirty)
+ flush_cache();
+ return cleanMerge;
+}
+
+static unsigned char *has_sha(const unsigned char *sha)
+{
+ return memcmp(sha, null_sha1, 20) == 0 ? NULL: (unsigned char *)sha;
+}
+
+/* Per entry merge function */
+static int process_entry(const char *path, struct stage_data *entry,
+ const char *branch1Name,
+ const char *branch2Name)
+{
+ /*
+ printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
+ print_index_entry("\tpath: ", entry);
+ */
+ int cleanMerge = 1;
+ unsigned char *oSha = has_sha(entry->stages[1].sha);
+ unsigned char *aSha = has_sha(entry->stages[2].sha);
+ unsigned char *bSha = has_sha(entry->stages[3].sha);
+ unsigned oMode = entry->stages[1].mode;
+ unsigned aMode = entry->stages[2].mode;
+ unsigned bMode = entry->stages[3].mode;
+
+ if ( oSha && (!aSha || !bSha) ) {
+ /* Case A: Deleted in one */
+ if ( (!aSha && !bSha) ||
+ (sha_eq(aSha, oSha) && !bSha) ||
+ (!aSha && sha_eq(bSha, oSha)) ) {
+ /* Deleted in both or deleted in one and
+ * unchanged in the other */
+ if ( aSha )
+ output("Removing %s", path);
+ remove_file(1, path);
+ } else {
+ /* Deleted in one and changed in the other */
+ cleanMerge = 0;
+ if ( !aSha ) {
+ output("CONFLICT (delete/modify): %s deleted in %s "
+ "and modified in %s. Version %s of %s left in tree.",
+ path, branch1Name,
+ branch2Name, branch2Name, path);
+ update_file(0, bSha, bMode, path);
+ } else {
+ output("CONFLICT (delete/modify): %s deleted in %s "
+ "and modified in %s. Version %s of %s left in tree.",
+ path, branch2Name,
+ branch1Name, branch1Name, path);
+ update_file(0, aSha, aMode, path);
+ }
+ }
+
+ } else if ( (!oSha && aSha && !bSha) ||
+ (!oSha && !aSha && bSha) ) {
+ /* Case B: Added in one. */
+ const char *addBranch;
+ const char *otherBranch;
+ unsigned mode;
+ const unsigned char *sha;
+ const char *conf;
+
+ if ( aSha ) {
+ addBranch = branch1Name;
+ otherBranch = branch2Name;
+ mode = aMode;
+ sha = aSha;
+ conf = "file/directory";
+ } else {
+ addBranch = branch2Name;
+ otherBranch = branch1Name;
+ mode = bMode;
+ sha = bSha;
+ conf = "directory/file";
+ }
+ if ( path_list_has_path(&currentDirectorySet, path) ) {
+ cleanMerge = 0;
+ const char *newPath = unique_path(path, addBranch);
+ output("CONFLICT (%s): There is a directory with name %s in %s. "
+ "Adding %s as %s",
+ conf, path, otherBranch, path, newPath);
+ remove_file(0, path);
+ update_file(0, sha, mode, newPath);
+ } else {
+ output("Adding %s", path);
+ update_file(1, sha, mode, path);
+ }
+ } else if ( !oSha && aSha && bSha ) {
+ /* Case C: Added in both (check for same permissions). */
+ if ( sha_eq(aSha, bSha) ) {
+ if ( aMode != bMode ) {
+ cleanMerge = 0;
+ output("CONFLICT: File %s added identically in both branches, "
+ "but permissions conflict %06o->%06o",
+ path, aMode, bMode);
+ output("CONFLICT: adding with permission: %06o", aMode);
+ update_file(0, aSha, aMode, path);
+ } else {
+ /* This case is handled by git-read-tree */
+ assert(0 && "This case must be handled by git-read-tree");
+ }
+ } else {
+ cleanMerge = 0;
+ const char *newPath1 = unique_path(path, branch1Name);
+ const char *newPath2 = unique_path(path, branch2Name);
+ output("CONFLICT (add/add): File %s added non-identically "
+ "in both branches. Adding as %s and %s instead.",
+ path, newPath1, newPath2);
+ remove_file(0, path);
+ update_file(0, aSha, aMode, newPath1);
+ update_file(0, bSha, bMode, newPath2);
+ }
+
+ } else if ( oSha && aSha && bSha ) {
+ /* case D: Modified in both, but differently. */
+ output("Auto-merging %s", path);
+ struct merge_file_info mfi;
+ mfi = merge_file(path, oSha, oMode,
+ path, aSha, aMode,
+ path, bSha, bMode,
+ branch1Name, branch2Name);
+
+ if ( mfi.clean )
+ update_file(1, mfi.sha, mfi.mode, path);
+ else {
+ cleanMerge = 0;
+ output("CONFLICT (content): Merge conflict in %s", path);
+
+ if ( index_only )
+ update_file(0, mfi.sha, mfi.mode, path);
+ else
+ update_file_flags(mfi.sha, mfi.mode, path,
+ 0 /* updateCache */, 1 /* updateWd */);
+ }
+ } else
+ die("Fatal merge failure, shouldn't happen.");
+
+ if (cache_dirty)
+ flush_cache();
+
+ return cleanMerge;
+}
+
+static struct merge_tree_result merge_trees(struct tree *head,
+ struct tree *merge,
+ struct tree *common,
+ const char *branch1Name,
+ const char *branch2Name)
+{
+ int code;
+ struct merge_tree_result result = { NULL, 0 };
+ if ( !memcmp(common->object.sha1, merge->object.sha1, 20) ) {
+ output("Already uptodate!");
+ result.tree = head;
+ result.clean = 1;
+ return result;
+ }
+
+ debug("merge_trees ...\n");
+ code = git_merge_trees(index_only ? "-i": "-u", 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));
+
+ result.tree = git_write_tree();
+
+ if ( !result.tree ) {
+ path_list_clear(&currentFileSet, 1);
+ path_list_clear(&currentDirectorySet, 1);
+ get_files_dirs(head, &currentFileSet, &currentDirectorySet);
+ get_files_dirs(merge, &currentFileSet, &currentDirectorySet);
+
+ struct path_list *entries = get_unmerged();
+ struct path_list *re_head, *re_merge;
+ re_head = get_renames(head, common, head, merge, entries);
+ re_merge = get_renames(merge, common, head, merge, entries);
+ result.clean = process_renames(re_head, re_merge,
+ branch1Name, branch2Name);
+ debug("\tprocessing entries...\n");
+ int i;
+ 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)
+ continue;
+ if (!process_entry(path, e, branch1Name, branch2Name))
+ result.clean = 0;
+ }
+
+ free_rename_entries(&re_merge);
+ free_rename_entries(&re_head);
+ free_index_entries(&entries);
+
+ if (result.clean || index_only)
+ result.tree = git_write_tree();
+ else
+ result.tree = NULL;
+ debug("\t processing entries done\n");
+ } else {
+ result.clean = 1;
+ printf("merging of trees %s and %s resulted in %s\n",
+ sha1_to_hex(head->object.sha1),
+ sha1_to_hex(merge->object.sha1),
+ sha1_to_hex(result.tree->object.sha1));
+ }
+
+ debug(" merge_trees done\n");
+ return result;
+}
+
+/*
+ * Merge the commits h1 and h2, return the resulting virtual
+ * commit object and a flag indicating the cleaness of the merge.
+ */
+static
+struct merge_result merge(struct commit *h1,
+ struct commit *h2,
+ const char *branch1Name,
+ const char *branch2Name,
+ int callDepth /* =0 */,
+ struct commit *ancestor /* =None */)
+{
+ struct merge_result result = { NULL, 0 };
+ const char *msg;
+ int msglen;
+ struct commit_list *ca = NULL, *iter;
+ struct commit *mergedCA;
+ struct merge_tree_result mtr;
+
+ output("Merging:");
+ msg = commit_title(h1, &msglen);
+ /* TODO: refactor. we always show the sha1 with the title */
+ output("%s %.*s", commit_hex_sha1(h1), msglen, msg);
+ msg = commit_title(h2, &msglen);
+ output("%s %.*s", commit_hex_sha1(h2), msglen, msg);
+
+ if ( ancestor )
+ commit_list_insert(ancestor, &ca);
+ else
+ ca = get_merge_bases(h1, h2, 1);
+
+ output("found %u common ancestor(s):", commit_list_count(ca));
+ for (iter = ca; iter; iter = iter->next) {
+ msg = commit_title(iter->item, &msglen);
+ output("%s %.*s", commit_hex_sha1(iter->item), msglen, msg);
+ }
+
+ mergedCA = pop_commit(&ca);
+
+ /* TODO: what happens when merge with virtual commits fails? */
+ for (iter = ca; iter; iter = iter->next) {
+ output_indent = callDepth + 1;
+ result = merge(mergedCA, iter->item,
+ "Temporary merge branch 1",
+ "Temporary merge branch 2",
+ callDepth + 1,
+ NULL);
+ mergedCA = result.commit;
+ output_indent = callDepth;
+
+ if ( !mergedCA )
+ die("merge returned no commit");
+ }
+
+ if ( callDepth == 0 ) {
+ setup_index(0);
+ index_only = 0;
+ } else {
+ setup_index(1);
+ git_read_tree(h1->tree);
+ index_only = 1;
+ }
+
+ mtr = merge_trees(h1->tree, h2->tree,
+ mergedCA->tree, branch1Name, branch2Name);
+
+ if ( !ancestor && (mtr.clean || index_only) ) {
+ result.commit = make_virtual_commit(mtr.tree, "merged tree");
+ commit_list_insert(h1, &result.commit->parents);
+ commit_list_insert(h2, &result.commit->parents->next);
+ } else
+ result.commit = NULL;
+
+ result.clean = mtr.clean;
+ return result;
+}
+
+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 != TYPE_COMMIT)
+ return NULL;
+ if (parse_commit((struct commit *)object))
+ die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
+ return (struct commit *)object;
+}
+
+int main(int argc, char *argv[])
+{
+ static const char *bases[2];
+ static unsigned bases_count = 0;
+
+ original_index_file = getenv("GIT_INDEX_FILE");
+
+ if (!original_index_file)
+ original_index_file = strdup(git_path("index"));
+
+ temporary_index_file = strdup(git_path("mrg-rcrsv-tmp-idx"));
+
+ if (argc < 4)
+ die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
+
+ int i;
+ 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.");
+
+ const char *branch1, *branch2;
+
+ branch1 = argv[++i];
+ branch2 = argv[++i];
+ printf("Merging %s with %s\n", branch1, branch2);
+
+ struct merge_result result;
+ struct commit *h1 = get_ref(branch1);
+ struct commit *h2 = get_ref(branch2);
+
+ if (bases_count == 1) {
+ struct commit *ancestor = get_ref(bases[0]);
+ result = merge(h1, h2, branch1, branch2, 0, ancestor);
+ } else
+ result = merge(h1, h2, branch1, branch2, 0, NULL);
+
+ if (cache_dirty)
+ flush_cache();
+
+ return result.clean ? 0: 1;
+}
+
+/*
+vim: sw=8 noet
+*/