2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
7 #include "cache-tree.h"
10 #include "tree-walk.h"
13 #include "run-command.h"
15 #include "unpack-trees.h"
16 #include "path-list.h"
17 #include "xdiff-interface.h"
20 * A virtual commit has
21 * - (const char *)commit->util set to the name, and
22 * - *(int *)commit->object.sha1 set to the virtual id.
25 static unsigned commit_list_count(const struct commit_list *l)
28 for (; l; l = l->next )
33 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
35 struct commit *commit = xcalloc(1, sizeof(struct commit));
36 static unsigned virtual_id = 1;
38 commit->util = (void*)comment;
39 *(int*)commit->object.sha1 = virtual_id++;
41 commit->object.parsed = 1;
46 * Since we use get_tree_entry(), which does not put the read object into
47 * the object pool, we cannot rely on a == b.
49 static int sha_eq(const unsigned char *a, const unsigned char *b)
53 return a && b && hashcmp(a, b) == 0;
57 * Since we want to write the index eventually, we cannot reuse the index
58 * for these (temporary) data.
65 unsigned char sha[20];
70 static struct path_list current_file_set = {NULL, 0, 0, 1};
71 static struct path_list current_directory_set = {NULL, 0, 0, 1};
73 static int call_depth = 0;
75 static void output(const char *fmt, ...)
79 for (i = call_depth; i--;)
82 vfprintf(stdout, fmt, args);
87 static void output_commit_title(struct commit *commit)
90 for (i = call_depth; i--;)
93 printf("virtual %s\n", (char *)commit->util);
95 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
96 if (parse_commit(commit) != 0)
97 printf("(bad commit)\n");
101 for (s = commit->buffer; *s; s++)
102 if (*s == '\n' && s[1] == '\n') {
106 for (len = 0; s[len] && '\n' != s[len]; len++)
108 printf("%.*s\n", len, s);
113 static struct cache_entry *make_cache_entry(unsigned int mode,
114 const unsigned char *sha1, const char *path, int stage, int refresh)
117 struct cache_entry *ce;
119 if (!verify_path(path))
123 size = cache_entry_size(len);
124 ce = xcalloc(1, size);
126 hashcpy(ce->sha1, sha1);
127 memcpy(ce->name, path, len);
128 ce->ce_flags = create_ce_flags(len, stage);
129 ce->ce_mode = create_ce_mode(mode);
132 return refresh_cache_entry(ce, 0);
137 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
138 const char *path, int stage, int refresh, int options)
140 struct cache_entry *ce;
141 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
143 return error("cache_addinfo failed: %s", strerror(cache_errno));
144 return add_cache_entry(ce, options);
148 * This is a global variable which is used in a number of places but
149 * only written to in the 'merge' function.
151 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
152 * don't update the working directory.
153 * 0 => Leave unmerged entries in the cache and update
154 * the working directory.
156 static int index_only = 0;
158 static int git_merge_trees(int index_only,
164 struct object_list *trees = NULL;
165 struct unpack_trees_options opts;
167 memset(&opts, 0, sizeof(opts));
174 opts.fn = threeway_merge;
176 object_list_append(&common->object, &trees);
177 object_list_append(&head->object, &trees);
178 object_list_append(&merge->object, &trees);
180 rc = unpack_trees(trees, &opts);
181 cache_tree_free(&active_cache_tree);
185 static int unmerged_index(void)
188 for (i = 0; i < active_nr; i++) {
189 struct cache_entry *ce = active_cache[i];
196 static struct tree *git_write_tree(void)
198 struct tree *result = NULL;
200 if (unmerged_index())
203 if (!active_cache_tree)
204 active_cache_tree = cache_tree();
206 if (!cache_tree_fully_valid(active_cache_tree) &&
207 cache_tree_update(active_cache_tree,
208 active_cache, active_nr, 0, 0) < 0)
209 die("error building trees");
211 result = lookup_tree(active_cache_tree->sha1);
216 static int save_files_dirs(const unsigned char *sha1,
217 const char *base, int baselen, const char *path,
218 unsigned int mode, int stage)
220 int len = strlen(path);
221 char *newpath = xmalloc(baselen + len + 1);
222 memcpy(newpath, base, baselen);
223 memcpy(newpath + baselen, path, len);
224 newpath[baselen + len] = '\0';
227 path_list_insert(newpath, ¤t_directory_set);
229 path_list_insert(newpath, ¤t_file_set);
232 return READ_TREE_RECURSIVE;
235 static int get_files_dirs(struct tree *tree)
238 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
240 n = current_file_set.nr + current_directory_set.nr;
245 * Returns a index_entry instance which doesn't have to correspond to
246 * a real cache entry in Git's index.
248 static struct stage_data *insert_stage_data(const char *path,
249 struct tree *o, struct tree *a, struct tree *b,
250 struct path_list *entries)
252 struct path_list_item *item;
253 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
254 get_tree_entry(o->object.sha1, path,
255 e->stages[1].sha, &e->stages[1].mode);
256 get_tree_entry(a->object.sha1, path,
257 e->stages[2].sha, &e->stages[2].mode);
258 get_tree_entry(b->object.sha1, path,
259 e->stages[3].sha, &e->stages[3].mode);
260 item = path_list_insert(path, entries);
266 * Create a dictionary mapping file names to stage_data objects. The
267 * dictionary contains one entry for every path with a non-zero stage entry.
269 static struct path_list *get_unmerged(void)
271 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
274 unmerged->strdup_paths = 1;
276 for (i = 0; i < active_nr; i++) {
277 struct path_list_item *item;
278 struct stage_data *e;
279 struct cache_entry *ce = active_cache[i];
283 item = path_list_lookup(ce->name, unmerged);
285 item = path_list_insert(ce->name, unmerged);
286 item->util = xcalloc(1, sizeof(struct stage_data));
289 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
290 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
298 struct diff_filepair *pair;
299 struct stage_data *src_entry;
300 struct stage_data *dst_entry;
301 unsigned processed:1;
305 * Get information of all renames which occured between 'o_tree' and
306 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
307 * 'b_tree') to be able to associate the correct cache entries with
308 * the rename information. 'tree' is always equal to either a_tree or b_tree.
310 static struct path_list *get_renames(struct tree *tree,
314 struct path_list *entries)
317 struct path_list *renames;
318 struct diff_options opts;
320 renames = xcalloc(1, sizeof(struct path_list));
323 opts.detect_rename = DIFF_DETECT_RENAME;
324 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
325 if (diff_setup_done(&opts) < 0)
326 die("diff setup failed");
327 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
329 for (i = 0; i < diff_queued_diff.nr; ++i) {
330 struct path_list_item *item;
332 struct diff_filepair *pair = diff_queued_diff.queue[i];
333 if (pair->status != 'R') {
334 diff_free_filepair(pair);
337 re = xmalloc(sizeof(*re));
340 item = path_list_lookup(re->pair->one->path, entries);
342 re->src_entry = insert_stage_data(re->pair->one->path,
343 o_tree, a_tree, b_tree, entries);
345 re->src_entry = item->util;
347 item = path_list_lookup(re->pair->two->path, entries);
349 re->dst_entry = insert_stage_data(re->pair->two->path,
350 o_tree, a_tree, b_tree, entries);
352 re->dst_entry = item->util;
353 item = path_list_insert(pair->one->path, renames);
356 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
357 diff_queued_diff.nr = 0;
362 static int update_stages(const char *path, struct diff_filespec *o,
363 struct diff_filespec *a, struct diff_filespec *b,
366 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
368 if (remove_file_from_cache(path))
371 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
374 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
377 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
382 static int remove_path(const char *name)
391 dirs = xmalloc(len+1);
392 memcpy(dirs, name, len);
394 while ((slash = strrchr(name, '/'))) {
397 if (rmdir(name) != 0)
404 static int remove_file(int clean, const char *path, int no_wd)
406 int update_cache = index_only || clean;
407 int update_working_directory = !index_only && !no_wd;
410 if (remove_file_from_cache(path))
413 if (update_working_directory) {
415 if (errno != ENOENT || errno != EISDIR)
422 static char *unique_path(const char *path, const char *branch)
424 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
427 char *p = newpath + strlen(path);
428 strcpy(newpath, path);
434 while (path_list_has_path(¤t_file_set, newpath) ||
435 path_list_has_path(¤t_directory_set, newpath) ||
436 lstat(newpath, &st) == 0)
437 sprintf(p, "_%d", suffix++);
439 path_list_insert(newpath, ¤t_file_set);
443 static int mkdir_p(const char *path, unsigned long mode)
445 /* path points to cache entries, so xstrdup before messing with it */
446 char *buf = xstrdup(path);
447 int result = safe_create_leading_directories(buf);
452 static void flush_buffer(int fd, const char *buf, unsigned long size)
455 long ret = write_in_full(fd, buf, size);
460 die("merge-recursive: %s", strerror(errno));
462 die("merge-recursive: disk full?");
469 static void update_file_flags(const unsigned char *sha,
483 buf = read_sha1_file(sha, type, &size);
485 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
486 if (strcmp(type, blob_type) != 0)
487 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
491 if (mkdir_p(path, 0777))
492 die("failed to create path %s: %s", path, strerror(errno));
498 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
500 die("failed to open %s: %s", path, strerror(errno));
501 flush_buffer(fd, buf, size);
503 } else if (S_ISLNK(mode)) {
504 char *lnk = xmalloc(size + 1);
505 memcpy(lnk, buf, size);
511 die("do not know what to do with %06o %s '%s'",
512 mode, sha1_to_hex(sha), path);
515 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
518 static void update_file(int clean,
519 const unsigned char *sha,
523 update_file_flags(sha, mode, path, index_only || clean, !index_only);
526 /* Low level file merging, update and removal */
528 struct merge_file_info
530 unsigned char sha[20];
536 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
541 if (!hashcmp(sha1, null_sha1)) {
542 mm->ptr = xstrdup("");
547 mm->ptr = read_sha1_file(sha1, type, &size);
548 if (!mm->ptr || strcmp(type, blob_type))
549 die("unable to read blob object %s", sha1_to_hex(sha1));
553 static struct merge_file_info merge_file(struct diff_filespec *o,
554 struct diff_filespec *a, struct diff_filespec *b,
555 const char *branch1, const char *branch2)
557 struct merge_file_info result;
561 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
563 if (S_ISREG(a->mode)) {
564 result.mode = a->mode;
565 hashcpy(result.sha, a->sha1);
567 result.mode = b->mode;
568 hashcpy(result.sha, b->sha1);
571 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
574 result.mode = a->mode == o->mode ? b->mode: a->mode;
576 if (sha_eq(a->sha1, o->sha1))
577 hashcpy(result.sha, b->sha1);
578 else if (sha_eq(b->sha1, o->sha1))
579 hashcpy(result.sha, a->sha1);
580 else if (S_ISREG(a->mode)) {
581 mmfile_t orig, src1, src2;
582 mmbuffer_t result_buf;
587 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
588 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
590 fill_mm(o->sha1, &orig);
591 fill_mm(a->sha1, &src1);
592 fill_mm(b->sha1, &src2);
594 memset(&xpp, 0, sizeof(xpp));
595 merge_status = xdl_merge(&orig,
598 &xpp, XDL_MERGE_ZEALOUS,
606 if ((merge_status < 0) || !result_buf.ptr)
607 die("Failed to execute internal merge");
609 if (write_sha1_file(result_buf.ptr, result_buf.size,
610 blob_type, result.sha))
611 die("Unable to add %s to database",
614 free(result_buf.ptr);
615 result.clean = (merge_status == 0);
617 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
618 die("cannot merge modes?");
620 hashcpy(result.sha, a->sha1);
622 if (!sha_eq(a->sha1, b->sha1))
630 static void conflict_rename_rename(struct rename *ren1,
637 const char *ren1_dst = ren1->pair->two->path;
638 const char *ren2_dst = ren2->pair->two->path;
639 const char *dst_name1 = ren1_dst;
640 const char *dst_name2 = ren2_dst;
641 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
642 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
643 output("%s is a directory in %s adding as %s instead",
644 ren1_dst, branch2, dst_name1);
645 remove_file(0, ren1_dst, 0);
647 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
648 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
649 output("%s is a directory in %s adding as %s instead",
650 ren2_dst, branch1, dst_name2);
651 remove_file(0, ren2_dst, 0);
653 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
654 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
659 static void conflict_rename_dir(struct rename *ren1,
662 char *new_path = unique_path(ren1->pair->two->path, branch1);
663 output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
664 remove_file(0, ren1->pair->two->path, 0);
665 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
669 static void conflict_rename_rename_2(struct rename *ren1,
674 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
675 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
676 output("Renaming %s to %s and %s to %s instead",
677 ren1->pair->one->path, new_path1,
678 ren2->pair->one->path, new_path2);
679 remove_file(0, ren1->pair->two->path, 0);
680 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
681 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
686 static int process_renames(struct path_list *a_renames,
687 struct path_list *b_renames,
688 const char *a_branch,
689 const char *b_branch)
691 int clean_merge = 1, i, j;
692 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
693 const struct rename *sre;
695 for (i = 0; i < a_renames->nr; i++) {
696 sre = a_renames->items[i].util;
697 path_list_insert(sre->pair->two->path, &a_by_dst)->util
700 for (i = 0; i < b_renames->nr; i++) {
701 sre = b_renames->items[i].util;
702 path_list_insert(sre->pair->two->path, &b_by_dst)->util
706 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
709 struct path_list *renames1, *renames2, *renames2Dst;
710 struct rename *ren1 = NULL, *ren2 = NULL;
711 const char *branch1, *branch2;
712 const char *ren1_src, *ren1_dst;
714 if (i >= a_renames->nr) {
716 ren2 = b_renames->items[j++].util;
717 } else if (j >= b_renames->nr) {
719 ren1 = a_renames->items[i++].util;
721 compare = strcmp(a_renames->items[i].path,
722 b_renames->items[j].path);
724 ren1 = a_renames->items[i++].util;
726 ren2 = b_renames->items[j++].util;
729 /* TODO: refactor, so that 1/2 are not needed */
731 renames1 = a_renames;
732 renames2 = b_renames;
733 renames2Dst = &b_by_dst;
738 renames1 = b_renames;
739 renames2 = a_renames;
740 renames2Dst = &a_by_dst;
747 src = ren1->pair->one->path;
749 ren1->dst_entry->processed = 1;
750 ren1->src_entry->processed = 1;
756 ren1_src = ren1->pair->one->path;
757 ren1_dst = ren1->pair->two->path;
760 const char *ren2_src = ren2->pair->one->path;
761 const char *ren2_dst = ren2->pair->two->path;
762 /* Renamed in 1 and renamed in 2 */
763 if (strcmp(ren1_src, ren2_src) != 0)
764 die("ren1.src != ren2.src");
765 ren2->dst_entry->processed = 1;
767 if (strcmp(ren1_dst, ren2_dst) != 0) {
769 output("CONFLICT (rename/rename): "
770 "Rename %s->%s in branch %s "
771 "rename %s->%s in %s",
772 src, ren1_dst, branch1,
773 src, ren2_dst, branch2);
774 conflict_rename_rename(ren1, branch1, ren2, branch2);
776 struct merge_file_info mfi;
777 remove_file(1, ren1_src, 1);
778 mfi = merge_file(ren1->pair->one,
783 if (mfi.merge || !mfi.clean)
784 output("Renaming %s->%s", src, ren1_dst);
787 output("Auto-merging %s", ren1_dst);
790 output("CONFLICT (content): merge conflict in %s",
795 update_stages(ren1_dst,
801 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
804 /* Renamed in 1, maybe changed in 2 */
805 struct path_list_item *item;
806 /* we only use sha1 and mode of these */
807 struct diff_filespec src_other, dst_other;
808 int try_merge, stage = a_renames == renames1 ? 3: 2;
810 remove_file(1, ren1_src, index_only);
812 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
813 src_other.mode = ren1->src_entry->stages[stage].mode;
814 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
815 dst_other.mode = ren1->dst_entry->stages[stage].mode;
819 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
821 output("CONFLICT (rename/directory): Rename %s->%s in %s "
822 " directory %s added in %s",
823 ren1_src, ren1_dst, branch1,
825 conflict_rename_dir(ren1, branch1);
826 } else if (sha_eq(src_other.sha1, null_sha1)) {
828 output("CONFLICT (rename/delete): Rename %s->%s in %s "
830 ren1_src, ren1_dst, branch1,
832 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
833 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
834 const char *new_path;
837 output("CONFLICT (rename/add): Rename %s->%s in %s. "
839 ren1_src, ren1_dst, branch1,
841 new_path = unique_path(ren1_dst, branch2);
842 output("Adding as %s instead", new_path);
843 update_file(0, dst_other.sha1, dst_other.mode, new_path);
844 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
848 output("CONFLICT (rename/rename): Rename %s->%s in %s. "
849 "Rename %s->%s in %s",
850 ren1_src, ren1_dst, branch1,
851 ren2->pair->one->path, ren2->pair->two->path, branch2);
852 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
857 struct diff_filespec *o, *a, *b;
858 struct merge_file_info mfi;
859 src_other.path = (char *)ren1_src;
862 if (a_renames == renames1) {
869 mfi = merge_file(o, a, b,
872 if (mfi.merge || !mfi.clean)
873 output("Renaming %s => %s", ren1_src, ren1_dst);
875 output("Auto-merging %s", ren1_dst);
877 output("CONFLICT (rename/modify): Merge conflict in %s",
882 update_stages(ren1_dst,
885 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
889 path_list_clear(&a_by_dst, 0);
890 path_list_clear(&b_by_dst, 0);
895 static unsigned char *has_sha(const unsigned char *sha)
897 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
900 /* Per entry merge function */
901 static int process_entry(const char *path, struct stage_data *entry,
906 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
907 print_index_entry("\tpath: ", entry);
910 unsigned char *o_sha = has_sha(entry->stages[1].sha);
911 unsigned char *a_sha = has_sha(entry->stages[2].sha);
912 unsigned char *b_sha = has_sha(entry->stages[3].sha);
913 unsigned o_mode = entry->stages[1].mode;
914 unsigned a_mode = entry->stages[2].mode;
915 unsigned b_mode = entry->stages[3].mode;
917 if (o_sha && (!a_sha || !b_sha)) {
918 /* Case A: Deleted in one */
919 if ((!a_sha && !b_sha) ||
920 (sha_eq(a_sha, o_sha) && !b_sha) ||
921 (!a_sha && sha_eq(b_sha, o_sha))) {
922 /* Deleted in both or deleted in one and
923 * unchanged in the other */
925 output("Removing %s", path);
926 /* do not touch working file if it did not exist */
927 remove_file(1, path, !a_sha);
929 /* Deleted in one and changed in the other */
932 output("CONFLICT (delete/modify): %s deleted in %s "
933 "and modified in %s. Version %s of %s left in tree.",
935 branch2, branch2, path);
936 update_file(0, b_sha, b_mode, path);
938 output("CONFLICT (delete/modify): %s deleted in %s "
939 "and modified in %s. Version %s of %s left in tree.",
941 branch1, branch1, path);
942 update_file(0, a_sha, a_mode, path);
946 } else if ((!o_sha && a_sha && !b_sha) ||
947 (!o_sha && !a_sha && b_sha)) {
948 /* Case B: Added in one. */
949 const char *add_branch;
950 const char *other_branch;
952 const unsigned char *sha;
956 add_branch = branch1;
957 other_branch = branch2;
960 conf = "file/directory";
962 add_branch = branch2;
963 other_branch = branch1;
966 conf = "directory/file";
968 if (path_list_has_path(¤t_directory_set, path)) {
969 const char *new_path = unique_path(path, add_branch);
971 output("CONFLICT (%s): There is a directory with name %s in %s. "
973 conf, path, other_branch, path, new_path);
974 remove_file(0, path, 0);
975 update_file(0, sha, mode, new_path);
977 output("Adding %s", path);
978 update_file(1, sha, mode, path);
980 } else if (a_sha && b_sha) {
981 /* Case C: Added in both (check for same permissions) and */
982 /* case D: Modified in both, but differently. */
983 const char *reason = "content";
984 struct merge_file_info mfi;
985 struct diff_filespec o, a, b;
989 o_sha = (unsigned char *)null_sha1;
991 output("Auto-merging %s", path);
992 o.path = a.path = b.path = (char *)path;
993 hashcpy(o.sha1, o_sha);
995 hashcpy(a.sha1, a_sha);
997 hashcpy(b.sha1, b_sha);
1000 mfi = merge_file(&o, &a, &b,
1004 update_file(1, mfi.sha, mfi.mode, path);
1007 output("CONFLICT (%s): Merge conflict in %s",
1011 update_file(0, mfi.sha, mfi.mode, path);
1013 update_file_flags(mfi.sha, mfi.mode, path,
1014 0 /* update_cache */, 1 /* update_working_directory */);
1017 die("Fatal merge failure, shouldn't happen.");
1022 static int merge_trees(struct tree *head,
1024 struct tree *common,
1025 const char *branch1,
1026 const char *branch2,
1027 struct tree **result)
1030 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1031 output("Already uptodate!");
1036 code = git_merge_trees(index_only, common, head, merge);
1039 die("merging of trees %s and %s failed",
1040 sha1_to_hex(head->object.sha1),
1041 sha1_to_hex(merge->object.sha1));
1043 if (unmerged_index()) {
1044 struct path_list *entries, *re_head, *re_merge;
1046 path_list_clear(¤t_file_set, 1);
1047 path_list_clear(¤t_directory_set, 1);
1048 get_files_dirs(head);
1049 get_files_dirs(merge);
1051 entries = get_unmerged();
1052 re_head = get_renames(head, common, head, merge, entries);
1053 re_merge = get_renames(merge, common, head, merge, entries);
1054 clean = process_renames(re_head, re_merge,
1056 for (i = 0; i < entries->nr; i++) {
1057 const char *path = entries->items[i].path;
1058 struct stage_data *e = entries->items[i].util;
1061 if (!process_entry(path, e, branch1, branch2))
1065 path_list_clear(re_merge, 0);
1066 path_list_clear(re_head, 0);
1067 path_list_clear(entries, 1);
1074 *result = git_write_tree();
1079 static struct commit_list *reverse_commit_list(struct commit_list *list)
1081 struct commit_list *next = NULL, *current, *backup;
1082 for (current = list; current; current = backup) {
1083 backup = current->next;
1084 current->next = next;
1091 * Merge the commits h1 and h2, return the resulting virtual
1092 * commit object and a flag indicating the cleaness of the merge.
1094 static int merge(struct commit *h1,
1096 const char *branch1,
1097 const char *branch2,
1098 struct commit_list *ca,
1099 struct commit **result)
1101 struct commit_list *iter;
1102 struct commit *merged_common_ancestors;
1103 struct tree *mrtree;
1107 output_commit_title(h1);
1108 output_commit_title(h2);
1111 ca = get_merge_bases(h1, h2, 1);
1112 ca = reverse_commit_list(ca);
1115 output("found %u common ancestor(s):", commit_list_count(ca));
1116 for (iter = ca; iter; iter = iter->next)
1117 output_commit_title(iter->item);
1119 merged_common_ancestors = pop_commit(&ca);
1120 if (merged_common_ancestors == NULL) {
1121 /* if there is no common ancestor, make an empty tree */
1122 struct tree *tree = xcalloc(1, sizeof(struct tree));
1124 tree->object.parsed = 1;
1125 tree->object.type = OBJ_TREE;
1126 write_sha1_file(NULL, 0, tree_type, tree->object.sha1);
1127 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1130 for (iter = ca; iter; iter = iter->next) {
1133 * When the merge fails, the result contains files
1134 * with conflict markers. The cleanness flag is
1135 * ignored, it was never acutally used, as result of
1136 * merge_trees has always overwritten it: the commited
1137 * "conflicts" were already resolved.
1140 merge(merged_common_ancestors, iter->item,
1141 "Temporary merge branch 1",
1142 "Temporary merge branch 2",
1144 &merged_common_ancestors);
1147 if (!merged_common_ancestors)
1148 die("merge returned no commit");
1158 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1159 branch1, branch2, &mrtree);
1162 *result = make_virtual_commit(mrtree, "merged tree");
1163 commit_list_insert(h1, &(*result)->parents);
1164 commit_list_insert(h2, &(*result)->parents->next);
1169 static const char *better_branch_name(const char *branch)
1171 static char githead_env[8 + 40 + 1];
1174 if (strlen(branch) != 40)
1176 sprintf(githead_env, "GITHEAD_%s", branch);
1177 name = getenv(githead_env);
1178 return name ? name : branch;
1181 static struct commit *get_ref(const char *ref)
1183 unsigned char sha1[20];
1184 struct object *object;
1186 if (get_sha1(ref, sha1))
1187 die("Could not resolve ref '%s'", ref);
1188 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1189 if (object->type == OBJ_TREE)
1190 return make_virtual_commit((struct tree*)object,
1191 better_branch_name(ref));
1192 if (object->type != OBJ_COMMIT)
1194 if (parse_commit((struct commit *)object))
1195 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1196 return (struct commit *)object;
1199 int main(int argc, char *argv[])
1201 static const char *bases[20];
1202 static unsigned bases_count = 0;
1204 const char *branch1, *branch2;
1205 struct commit *result, *h1, *h2;
1206 struct commit_list *ca = NULL;
1207 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1210 git_config(git_default_config); /* core.filemode */
1213 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1215 for (i = 1; i < argc; ++i) {
1216 if (!strcmp(argv[i], "--"))
1218 if (bases_count < sizeof(bases)/sizeof(*bases))
1219 bases[bases_count++] = argv[i];
1221 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1222 die("Not handling anything other than two heads merge.");
1224 branch1 = argv[++i];
1225 branch2 = argv[++i];
1227 h1 = get_ref(branch1);
1228 h2 = get_ref(branch2);
1230 branch1 = better_branch_name(branch1);
1231 branch2 = better_branch_name(branch2);
1232 printf("Merging %s with %s\n", branch1, branch2);
1234 index_fd = hold_lock_file_for_update(lock, get_index_file(), 1);
1236 for (i = 0; i < bases_count; i++) {
1237 struct commit *ancestor = get_ref(bases[i]);
1238 ca = commit_list_insert(ancestor, &ca);
1240 clean = merge(h1, h2, branch1, branch2, ca, &result);
1242 if (active_cache_changed &&
1243 (write_cache(index_fd, active_cache, active_nr) ||
1244 close(index_fd) || commit_lock_file(lock)))
1245 die ("unable to write %s", get_index_file());
1247 return clean ? 0: 1;