Simplify and rename find_sha1_file()
[git/git-svn.git] / builtin-merge-recursive.c
blob4aa28a1babbb275df8110fd80311f34a12fea750
1 /*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6 #include "cache.h"
7 #include "cache-tree.h"
8 #include "commit.h"
9 #include "blob.h"
10 #include "builtin.h"
11 #include "tree-walk.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "tag.h"
15 #include "unpack-trees.h"
16 #include "path-list.h"
17 #include "xdiff-interface.h"
18 #include "ll-merge.h"
19 #include "interpolate.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
23 static int subtree_merge;
25 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
27 unsigned char shifted[20];
30 * NEEDSWORK: this limits the recursion depth to hardcoded
31 * value '2' to avoid excessive overhead.
33 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
34 if (!hashcmp(two->object.sha1, shifted))
35 return two;
36 return lookup_tree(shifted);
40 * A virtual commit has
41 * - (const char *)commit->util set to the name, and
42 * - *(int *)commit->object.sha1 set to the virtual id.
45 static unsigned commit_list_count(const struct commit_list *l)
47 unsigned c = 0;
48 for (; l; l = l->next )
49 c++;
50 return c;
53 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
55 struct commit *commit = xcalloc(1, sizeof(struct commit));
56 static unsigned virtual_id = 1;
57 commit->tree = tree;
58 commit->util = (void*)comment;
59 *(int*)commit->object.sha1 = virtual_id++;
60 /* avoid warnings */
61 commit->object.parsed = 1;
62 return commit;
66 * Since we use get_tree_entry(), which does not put the read object into
67 * the object pool, we cannot rely on a == b.
69 static int sha_eq(const unsigned char *a, const unsigned char *b)
71 if (!a && !b)
72 return 2;
73 return a && b && hashcmp(a, b) == 0;
77 * Since we want to write the index eventually, we cannot reuse the index
78 * for these (temporary) data.
80 struct stage_data
82 struct
84 unsigned mode;
85 unsigned char sha[20];
86 } stages[4];
87 unsigned processed:1;
90 static struct path_list current_file_set = {NULL, 0, 0, 1};
91 static struct path_list current_directory_set = {NULL, 0, 0, 1};
93 static int call_depth = 0;
94 static int verbosity = 2;
95 static int diff_rename_limit = -1;
96 static int merge_rename_limit = -1;
97 static int buffer_output = 1;
98 static struct strbuf obuf = STRBUF_INIT;
100 static int show(int v)
102 return (!call_depth && verbosity >= v) || verbosity >= 5;
105 static void flush_output(void)
107 if (obuf.len) {
108 fputs(obuf.buf, stdout);
109 strbuf_reset(&obuf);
113 static void output(int v, const char *fmt, ...)
115 int len;
116 va_list ap;
118 if (!show(v))
119 return;
121 strbuf_grow(&obuf, call_depth * 2 + 2);
122 memset(obuf.buf + obuf.len, ' ', call_depth * 2);
123 strbuf_setlen(&obuf, obuf.len + call_depth * 2);
125 va_start(ap, fmt);
126 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
127 va_end(ap);
129 if (len < 0)
130 len = 0;
131 if (len >= strbuf_avail(&obuf)) {
132 strbuf_grow(&obuf, len + 2);
133 va_start(ap, fmt);
134 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
135 va_end(ap);
136 if (len >= strbuf_avail(&obuf)) {
137 die("this should not happen, your snprintf is broken");
140 strbuf_setlen(&obuf, obuf.len + len);
141 strbuf_add(&obuf, "\n", 1);
142 if (!buffer_output)
143 flush_output();
146 static void output_commit_title(struct commit *commit)
148 int i;
149 flush_output();
150 for (i = call_depth; i--;)
151 fputs(" ", stdout);
152 if (commit->util)
153 printf("virtual %s\n", (char *)commit->util);
154 else {
155 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
156 if (parse_commit(commit) != 0)
157 printf("(bad commit)\n");
158 else {
159 const char *s;
160 int len;
161 for (s = commit->buffer; *s; s++)
162 if (*s == '\n' && s[1] == '\n') {
163 s += 2;
164 break;
166 for (len = 0; s[len] && '\n' != s[len]; len++)
167 ; /* do nothing */
168 printf("%.*s\n", len, s);
173 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
174 const char *path, int stage, int refresh, int options)
176 struct cache_entry *ce;
177 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
178 if (!ce)
179 return error("addinfo_cache failed for path '%s'", path);
180 return add_cache_entry(ce, options);
184 * This is a global variable which is used in a number of places but
185 * only written to in the 'merge' function.
187 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
188 * don't update the working directory.
189 * 0 => Leave unmerged entries in the cache and update
190 * the working directory.
192 static int index_only = 0;
194 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
196 parse_tree(tree);
197 init_tree_desc(desc, tree->buffer, tree->size);
200 static int git_merge_trees(int index_only,
201 struct tree *common,
202 struct tree *head,
203 struct tree *merge)
205 int rc;
206 struct tree_desc t[3];
207 struct unpack_trees_options opts;
209 memset(&opts, 0, sizeof(opts));
210 if (index_only)
211 opts.index_only = 1;
212 else
213 opts.update = 1;
214 opts.merge = 1;
215 opts.head_idx = 2;
216 opts.fn = threeway_merge;
217 opts.src_index = &the_index;
218 opts.dst_index = &the_index;
220 init_tree_desc_from_tree(t+0, common);
221 init_tree_desc_from_tree(t+1, head);
222 init_tree_desc_from_tree(t+2, merge);
224 rc = unpack_trees(3, t, &opts);
225 cache_tree_free(&active_cache_tree);
226 return rc;
229 struct tree *write_tree_from_memory(void)
231 struct tree *result = NULL;
233 if (unmerged_cache()) {
234 int i;
235 output(0, "There are unmerged index entries:");
236 for (i = 0; i < active_nr; i++) {
237 struct cache_entry *ce = active_cache[i];
238 if (ce_stage(ce))
239 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
241 return NULL;
244 if (!active_cache_tree)
245 active_cache_tree = cache_tree();
247 if (!cache_tree_fully_valid(active_cache_tree) &&
248 cache_tree_update(active_cache_tree,
249 active_cache, active_nr, 0, 0) < 0)
250 die("error building trees");
252 result = lookup_tree(active_cache_tree->sha1);
254 return result;
257 static int save_files_dirs(const unsigned char *sha1,
258 const char *base, int baselen, const char *path,
259 unsigned int mode, int stage)
261 int len = strlen(path);
262 char *newpath = xmalloc(baselen + len + 1);
263 memcpy(newpath, base, baselen);
264 memcpy(newpath + baselen, path, len);
265 newpath[baselen + len] = '\0';
267 if (S_ISDIR(mode))
268 path_list_insert(newpath, &current_directory_set);
269 else
270 path_list_insert(newpath, &current_file_set);
271 free(newpath);
273 return READ_TREE_RECURSIVE;
276 static int get_files_dirs(struct tree *tree)
278 int n;
279 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
280 return 0;
281 n = current_file_set.nr + current_directory_set.nr;
282 return n;
286 * Returns an index_entry instance which doesn't have to correspond to
287 * a real cache entry in Git's index.
289 static struct stage_data *insert_stage_data(const char *path,
290 struct tree *o, struct tree *a, struct tree *b,
291 struct path_list *entries)
293 struct path_list_item *item;
294 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
295 get_tree_entry(o->object.sha1, path,
296 e->stages[1].sha, &e->stages[1].mode);
297 get_tree_entry(a->object.sha1, path,
298 e->stages[2].sha, &e->stages[2].mode);
299 get_tree_entry(b->object.sha1, path,
300 e->stages[3].sha, &e->stages[3].mode);
301 item = path_list_insert(path, entries);
302 item->util = e;
303 return e;
307 * Create a dictionary mapping file names to stage_data objects. The
308 * dictionary contains one entry for every path with a non-zero stage entry.
310 static struct path_list *get_unmerged(void)
312 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
313 int i;
315 unmerged->strdup_paths = 1;
317 for (i = 0; i < active_nr; i++) {
318 struct path_list_item *item;
319 struct stage_data *e;
320 struct cache_entry *ce = active_cache[i];
321 if (!ce_stage(ce))
322 continue;
324 item = path_list_lookup(ce->name, unmerged);
325 if (!item) {
326 item = path_list_insert(ce->name, unmerged);
327 item->util = xcalloc(1, sizeof(struct stage_data));
329 e = item->util;
330 e->stages[ce_stage(ce)].mode = ce->ce_mode;
331 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
334 return unmerged;
337 struct rename
339 struct diff_filepair *pair;
340 struct stage_data *src_entry;
341 struct stage_data *dst_entry;
342 unsigned processed:1;
346 * Get information of all renames which occurred between 'o_tree' and
347 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
348 * 'b_tree') to be able to associate the correct cache entries with
349 * the rename information. 'tree' is always equal to either a_tree or b_tree.
351 static struct path_list *get_renames(struct tree *tree,
352 struct tree *o_tree,
353 struct tree *a_tree,
354 struct tree *b_tree,
355 struct path_list *entries)
357 int i;
358 struct path_list *renames;
359 struct diff_options opts;
361 renames = xcalloc(1, sizeof(struct path_list));
362 diff_setup(&opts);
363 DIFF_OPT_SET(&opts, RECURSIVE);
364 opts.detect_rename = DIFF_DETECT_RENAME;
365 opts.rename_limit = merge_rename_limit >= 0 ? merge_rename_limit :
366 diff_rename_limit >= 0 ? diff_rename_limit :
367 500;
368 opts.warn_on_too_large_rename = 1;
369 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
370 if (diff_setup_done(&opts) < 0)
371 die("diff setup failed");
372 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
373 diffcore_std(&opts);
374 for (i = 0; i < diff_queued_diff.nr; ++i) {
375 struct path_list_item *item;
376 struct rename *re;
377 struct diff_filepair *pair = diff_queued_diff.queue[i];
378 if (pair->status != 'R') {
379 diff_free_filepair(pair);
380 continue;
382 re = xmalloc(sizeof(*re));
383 re->processed = 0;
384 re->pair = pair;
385 item = path_list_lookup(re->pair->one->path, entries);
386 if (!item)
387 re->src_entry = insert_stage_data(re->pair->one->path,
388 o_tree, a_tree, b_tree, entries);
389 else
390 re->src_entry = item->util;
392 item = path_list_lookup(re->pair->two->path, entries);
393 if (!item)
394 re->dst_entry = insert_stage_data(re->pair->two->path,
395 o_tree, a_tree, b_tree, entries);
396 else
397 re->dst_entry = item->util;
398 item = path_list_insert(pair->one->path, renames);
399 item->util = re;
401 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
402 diff_queued_diff.nr = 0;
403 diff_flush(&opts);
404 return renames;
407 static int update_stages(const char *path, struct diff_filespec *o,
408 struct diff_filespec *a, struct diff_filespec *b,
409 int clear)
411 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
412 if (clear)
413 if (remove_file_from_cache(path))
414 return -1;
415 if (o)
416 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
417 return -1;
418 if (a)
419 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
420 return -1;
421 if (b)
422 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
423 return -1;
424 return 0;
427 static int remove_path(const char *name)
429 int ret;
430 char *slash, *dirs;
432 ret = unlink(name);
433 if (ret)
434 return ret;
435 dirs = xstrdup(name);
436 while ((slash = strrchr(name, '/'))) {
437 *slash = '\0';
438 if (rmdir(name) != 0)
439 break;
441 free(dirs);
442 return ret;
445 static int remove_file(int clean, const char *path, int no_wd)
447 int update_cache = index_only || clean;
448 int update_working_directory = !index_only && !no_wd;
450 if (update_cache) {
451 if (remove_file_from_cache(path))
452 return -1;
454 if (update_working_directory) {
455 unlink(path);
456 if (errno != ENOENT || errno != EISDIR)
457 return -1;
458 remove_path(path);
460 return 0;
463 static char *unique_path(const char *path, const char *branch)
465 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
466 int suffix = 0;
467 struct stat st;
468 char *p = newpath + strlen(path);
469 strcpy(newpath, path);
470 *(p++) = '~';
471 strcpy(p, branch);
472 for (; *p; ++p)
473 if ('/' == *p)
474 *p = '_';
475 while (path_list_has_path(&current_file_set, newpath) ||
476 path_list_has_path(&current_directory_set, newpath) ||
477 lstat(newpath, &st) == 0)
478 sprintf(p, "_%d", suffix++);
480 path_list_insert(newpath, &current_file_set);
481 return newpath;
484 static int mkdir_p(const char *path, unsigned long mode)
486 /* path points to cache entries, so xstrdup before messing with it */
487 char *buf = xstrdup(path);
488 int result = safe_create_leading_directories(buf);
489 free(buf);
490 return result;
493 static void flush_buffer(int fd, const char *buf, unsigned long size)
495 while (size > 0) {
496 long ret = write_in_full(fd, buf, size);
497 if (ret < 0) {
498 /* Ignore epipe */
499 if (errno == EPIPE)
500 break;
501 die("merge-recursive: %s", strerror(errno));
502 } else if (!ret) {
503 die("merge-recursive: disk full?");
505 size -= ret;
506 buf += ret;
510 static int make_room_for_path(const char *path)
512 int status;
513 const char *msg = "failed to create path '%s'%s";
515 status = mkdir_p(path, 0777);
516 if (status) {
517 if (status == -3) {
518 /* something else exists */
519 error(msg, path, ": perhaps a D/F conflict?");
520 return -1;
522 die(msg, path, "");
525 /* Successful unlink is good.. */
526 if (!unlink(path))
527 return 0;
528 /* .. and so is no existing file */
529 if (errno == ENOENT)
530 return 0;
531 /* .. but not some other error (who really cares what?) */
532 return error(msg, path, ": perhaps a D/F conflict?");
535 static void update_file_flags(const unsigned char *sha,
536 unsigned mode,
537 const char *path,
538 int update_cache,
539 int update_wd)
541 if (index_only)
542 update_wd = 0;
544 if (update_wd) {
545 enum object_type type;
546 void *buf;
547 unsigned long size;
549 if (S_ISGITLINK(mode))
550 die("cannot read object %s '%s': It is a submodule!",
551 sha1_to_hex(sha), path);
553 buf = read_sha1_file(sha, &type, &size);
554 if (!buf)
555 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
556 if (type != OBJ_BLOB)
557 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
558 if (S_ISREG(mode)) {
559 struct strbuf strbuf;
560 strbuf_init(&strbuf, 0);
561 if (convert_to_working_tree(path, buf, size, &strbuf)) {
562 free(buf);
563 size = strbuf.len;
564 buf = strbuf_detach(&strbuf, NULL);
568 if (make_room_for_path(path) < 0) {
569 update_wd = 0;
570 free(buf);
571 goto update_index;
573 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
574 int fd;
575 if (mode & 0100)
576 mode = 0777;
577 else
578 mode = 0666;
579 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
580 if (fd < 0)
581 die("failed to open %s: %s", path, strerror(errno));
582 flush_buffer(fd, buf, size);
583 close(fd);
584 } else if (S_ISLNK(mode)) {
585 char *lnk = xmemdupz(buf, size);
586 mkdir_p(path, 0777);
587 unlink(path);
588 symlink(lnk, path);
589 free(lnk);
590 } else
591 die("do not know what to do with %06o %s '%s'",
592 mode, sha1_to_hex(sha), path);
593 free(buf);
595 update_index:
596 if (update_cache)
597 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
600 static void update_file(int clean,
601 const unsigned char *sha,
602 unsigned mode,
603 const char *path)
605 update_file_flags(sha, mode, path, index_only || clean, !index_only);
608 /* Low level file merging, update and removal */
610 struct merge_file_info
612 unsigned char sha[20];
613 unsigned mode;
614 unsigned clean:1,
615 merge:1;
618 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
620 unsigned long size;
621 enum object_type type;
623 if (!hashcmp(sha1, null_sha1)) {
624 mm->ptr = xstrdup("");
625 mm->size = 0;
626 return;
629 mm->ptr = read_sha1_file(sha1, &type, &size);
630 if (!mm->ptr || type != OBJ_BLOB)
631 die("unable to read blob object %s", sha1_to_hex(sha1));
632 mm->size = size;
635 static int merge_3way(mmbuffer_t *result_buf,
636 struct diff_filespec *o,
637 struct diff_filespec *a,
638 struct diff_filespec *b,
639 const char *branch1,
640 const char *branch2)
642 mmfile_t orig, src1, src2;
643 char *name1, *name2;
644 int merge_status;
646 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
647 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
649 fill_mm(o->sha1, &orig);
650 fill_mm(a->sha1, &src1);
651 fill_mm(b->sha1, &src2);
653 merge_status = ll_merge(result_buf, a->path, &orig,
654 &src1, name1, &src2, name2,
655 index_only);
657 free(name1);
658 free(name2);
659 free(orig.ptr);
660 free(src1.ptr);
661 free(src2.ptr);
662 return merge_status;
665 static struct merge_file_info merge_file(struct diff_filespec *o,
666 struct diff_filespec *a, struct diff_filespec *b,
667 const char *branch1, const char *branch2)
669 struct merge_file_info result;
670 result.merge = 0;
671 result.clean = 1;
673 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
674 result.clean = 0;
675 if (S_ISREG(a->mode)) {
676 result.mode = a->mode;
677 hashcpy(result.sha, a->sha1);
678 } else {
679 result.mode = b->mode;
680 hashcpy(result.sha, b->sha1);
682 } else {
683 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
684 result.merge = 1;
687 * Merge modes
689 if (a->mode == b->mode || a->mode == o->mode)
690 result.mode = b->mode;
691 else {
692 result.mode = a->mode;
693 if (b->mode != o->mode) {
694 result.clean = 0;
695 result.merge = 1;
699 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, o->sha1))
700 hashcpy(result.sha, b->sha1);
701 else if (sha_eq(b->sha1, o->sha1))
702 hashcpy(result.sha, a->sha1);
703 else if (S_ISREG(a->mode)) {
704 mmbuffer_t result_buf;
705 int merge_status;
707 merge_status = merge_3way(&result_buf, o, a, b,
708 branch1, branch2);
710 if ((merge_status < 0) || !result_buf.ptr)
711 die("Failed to execute internal merge");
713 if (write_sha1_file(result_buf.ptr, result_buf.size,
714 blob_type, result.sha))
715 die("Unable to add %s to database",
716 a->path);
718 free(result_buf.ptr);
719 result.clean = (merge_status == 0);
720 } else if (S_ISGITLINK(a->mode)) {
721 result.clean = 0;
722 hashcpy(result.sha, a->sha1);
723 } else if (S_ISLNK(a->mode)) {
724 hashcpy(result.sha, a->sha1);
726 if (!sha_eq(a->sha1, b->sha1))
727 result.clean = 0;
728 } else {
729 die("unsupported object type in the tree");
733 return result;
736 static void conflict_rename_rename(struct rename *ren1,
737 const char *branch1,
738 struct rename *ren2,
739 const char *branch2)
741 char *del[2];
742 int delp = 0;
743 const char *ren1_dst = ren1->pair->two->path;
744 const char *ren2_dst = ren2->pair->two->path;
745 const char *dst_name1 = ren1_dst;
746 const char *dst_name2 = ren2_dst;
747 if (path_list_has_path(&current_directory_set, ren1_dst)) {
748 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
749 output(1, "%s is a directory in %s added as %s instead",
750 ren1_dst, branch2, dst_name1);
751 remove_file(0, ren1_dst, 0);
753 if (path_list_has_path(&current_directory_set, ren2_dst)) {
754 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
755 output(1, "%s is a directory in %s added as %s instead",
756 ren2_dst, branch1, dst_name2);
757 remove_file(0, ren2_dst, 0);
759 if (index_only) {
760 remove_file_from_cache(dst_name1);
761 remove_file_from_cache(dst_name2);
763 * Uncomment to leave the conflicting names in the resulting tree
765 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
766 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
768 } else {
769 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
770 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
772 while (delp--)
773 free(del[delp]);
776 static void conflict_rename_dir(struct rename *ren1,
777 const char *branch1)
779 char *new_path = unique_path(ren1->pair->two->path, branch1);
780 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
781 remove_file(0, ren1->pair->two->path, 0);
782 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
783 free(new_path);
786 static void conflict_rename_rename_2(struct rename *ren1,
787 const char *branch1,
788 struct rename *ren2,
789 const char *branch2)
791 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
792 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
793 output(1, "Renamed %s to %s and %s to %s instead",
794 ren1->pair->one->path, new_path1,
795 ren2->pair->one->path, new_path2);
796 remove_file(0, ren1->pair->two->path, 0);
797 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
798 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
799 free(new_path2);
800 free(new_path1);
803 static int process_renames(struct path_list *a_renames,
804 struct path_list *b_renames,
805 const char *a_branch,
806 const char *b_branch)
808 int clean_merge = 1, i, j;
809 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
810 const struct rename *sre;
812 for (i = 0; i < a_renames->nr; i++) {
813 sre = a_renames->items[i].util;
814 path_list_insert(sre->pair->two->path, &a_by_dst)->util
815 = sre->dst_entry;
817 for (i = 0; i < b_renames->nr; i++) {
818 sre = b_renames->items[i].util;
819 path_list_insert(sre->pair->two->path, &b_by_dst)->util
820 = sre->dst_entry;
823 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
824 int compare;
825 char *src;
826 struct path_list *renames1, *renames2, *renames2Dst;
827 struct rename *ren1 = NULL, *ren2 = NULL;
828 const char *branch1, *branch2;
829 const char *ren1_src, *ren1_dst;
831 if (i >= a_renames->nr) {
832 compare = 1;
833 ren2 = b_renames->items[j++].util;
834 } else if (j >= b_renames->nr) {
835 compare = -1;
836 ren1 = a_renames->items[i++].util;
837 } else {
838 compare = strcmp(a_renames->items[i].path,
839 b_renames->items[j].path);
840 if (compare <= 0)
841 ren1 = a_renames->items[i++].util;
842 if (compare >= 0)
843 ren2 = b_renames->items[j++].util;
846 /* TODO: refactor, so that 1/2 are not needed */
847 if (ren1) {
848 renames1 = a_renames;
849 renames2 = b_renames;
850 renames2Dst = &b_by_dst;
851 branch1 = a_branch;
852 branch2 = b_branch;
853 } else {
854 struct rename *tmp;
855 renames1 = b_renames;
856 renames2 = a_renames;
857 renames2Dst = &a_by_dst;
858 branch1 = b_branch;
859 branch2 = a_branch;
860 tmp = ren2;
861 ren2 = ren1;
862 ren1 = tmp;
864 src = ren1->pair->one->path;
866 ren1->dst_entry->processed = 1;
867 ren1->src_entry->processed = 1;
869 if (ren1->processed)
870 continue;
871 ren1->processed = 1;
873 ren1_src = ren1->pair->one->path;
874 ren1_dst = ren1->pair->two->path;
876 if (ren2) {
877 const char *ren2_src = ren2->pair->one->path;
878 const char *ren2_dst = ren2->pair->two->path;
879 /* Renamed in 1 and renamed in 2 */
880 if (strcmp(ren1_src, ren2_src) != 0)
881 die("ren1.src != ren2.src");
882 ren2->dst_entry->processed = 1;
883 ren2->processed = 1;
884 if (strcmp(ren1_dst, ren2_dst) != 0) {
885 clean_merge = 0;
886 output(1, "CONFLICT (rename/rename): "
887 "Rename \"%s\"->\"%s\" in branch \"%s\" "
888 "rename \"%s\"->\"%s\" in \"%s\"%s",
889 src, ren1_dst, branch1,
890 src, ren2_dst, branch2,
891 index_only ? " (left unresolved)": "");
892 if (index_only) {
893 remove_file_from_cache(src);
894 update_file(0, ren1->pair->one->sha1,
895 ren1->pair->one->mode, src);
897 conflict_rename_rename(ren1, branch1, ren2, branch2);
898 } else {
899 struct merge_file_info mfi;
900 remove_file(1, ren1_src, 1);
901 mfi = merge_file(ren1->pair->one,
902 ren1->pair->two,
903 ren2->pair->two,
904 branch1,
905 branch2);
906 if (mfi.merge || !mfi.clean)
907 output(1, "Renamed %s->%s", src, ren1_dst);
909 if (mfi.merge)
910 output(2, "Auto-merged %s", ren1_dst);
912 if (!mfi.clean) {
913 output(1, "CONFLICT (content): merge conflict in %s",
914 ren1_dst);
915 clean_merge = 0;
917 if (!index_only)
918 update_stages(ren1_dst,
919 ren1->pair->one,
920 ren1->pair->two,
921 ren2->pair->two,
922 1 /* clear */);
924 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
926 } else {
927 /* Renamed in 1, maybe changed in 2 */
928 struct path_list_item *item;
929 /* we only use sha1 and mode of these */
930 struct diff_filespec src_other, dst_other;
931 int try_merge, stage = a_renames == renames1 ? 3: 2;
933 remove_file(1, ren1_src, index_only || stage == 3);
935 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
936 src_other.mode = ren1->src_entry->stages[stage].mode;
937 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
938 dst_other.mode = ren1->dst_entry->stages[stage].mode;
940 try_merge = 0;
942 if (path_list_has_path(&current_directory_set, ren1_dst)) {
943 clean_merge = 0;
944 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
945 " directory %s added in %s",
946 ren1_src, ren1_dst, branch1,
947 ren1_dst, branch2);
948 conflict_rename_dir(ren1, branch1);
949 } else if (sha_eq(src_other.sha1, null_sha1)) {
950 clean_merge = 0;
951 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
952 "and deleted in %s",
953 ren1_src, ren1_dst, branch1,
954 branch2);
955 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
956 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
957 const char *new_path;
958 clean_merge = 0;
959 try_merge = 1;
960 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
961 "%s added in %s",
962 ren1_src, ren1_dst, branch1,
963 ren1_dst, branch2);
964 new_path = unique_path(ren1_dst, branch2);
965 output(1, "Added as %s instead", new_path);
966 update_file(0, dst_other.sha1, dst_other.mode, new_path);
967 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
968 ren2 = item->util;
969 clean_merge = 0;
970 ren2->processed = 1;
971 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
972 "Renamed %s->%s in %s",
973 ren1_src, ren1_dst, branch1,
974 ren2->pair->one->path, ren2->pair->two->path, branch2);
975 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
976 } else
977 try_merge = 1;
979 if (try_merge) {
980 struct diff_filespec *o, *a, *b;
981 struct merge_file_info mfi;
982 src_other.path = (char *)ren1_src;
984 o = ren1->pair->one;
985 if (a_renames == renames1) {
986 a = ren1->pair->two;
987 b = &src_other;
988 } else {
989 b = ren1->pair->two;
990 a = &src_other;
992 mfi = merge_file(o, a, b,
993 a_branch, b_branch);
995 if (mfi.clean &&
996 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
997 mfi.mode == ren1->pair->two->mode)
999 * This messaged is part of
1000 * t6022 test. If you change
1001 * it update the test too.
1003 output(3, "Skipped %s (merged same as existing)", ren1_dst);
1004 else {
1005 if (mfi.merge || !mfi.clean)
1006 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
1007 if (mfi.merge)
1008 output(2, "Auto-merged %s", ren1_dst);
1009 if (!mfi.clean) {
1010 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
1011 ren1_dst);
1012 clean_merge = 0;
1014 if (!index_only)
1015 update_stages(ren1_dst,
1016 o, a, b, 1);
1018 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1023 path_list_clear(&a_by_dst, 0);
1024 path_list_clear(&b_by_dst, 0);
1026 return clean_merge;
1029 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1031 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1034 /* Per entry merge function */
1035 static int process_entry(const char *path, struct stage_data *entry,
1036 const char *branch1,
1037 const char *branch2)
1040 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1041 print_index_entry("\tpath: ", entry);
1043 int clean_merge = 1;
1044 unsigned o_mode = entry->stages[1].mode;
1045 unsigned a_mode = entry->stages[2].mode;
1046 unsigned b_mode = entry->stages[3].mode;
1047 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1048 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1049 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1051 if (o_sha && (!a_sha || !b_sha)) {
1052 /* Case A: Deleted in one */
1053 if ((!a_sha && !b_sha) ||
1054 (sha_eq(a_sha, o_sha) && !b_sha) ||
1055 (!a_sha && sha_eq(b_sha, o_sha))) {
1056 /* Deleted in both or deleted in one and
1057 * unchanged in the other */
1058 if (a_sha)
1059 output(2, "Removed %s", path);
1060 /* do not touch working file if it did not exist */
1061 remove_file(1, path, !a_sha);
1062 } else {
1063 /* Deleted in one and changed in the other */
1064 clean_merge = 0;
1065 if (!a_sha) {
1066 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1067 "and modified in %s. Version %s of %s left in tree.",
1068 path, branch1,
1069 branch2, branch2, path);
1070 update_file(0, b_sha, b_mode, path);
1071 } else {
1072 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1073 "and modified in %s. Version %s of %s left in tree.",
1074 path, branch2,
1075 branch1, branch1, path);
1076 update_file(0, a_sha, a_mode, path);
1080 } else if ((!o_sha && a_sha && !b_sha) ||
1081 (!o_sha && !a_sha && b_sha)) {
1082 /* Case B: Added in one. */
1083 const char *add_branch;
1084 const char *other_branch;
1085 unsigned mode;
1086 const unsigned char *sha;
1087 const char *conf;
1089 if (a_sha) {
1090 add_branch = branch1;
1091 other_branch = branch2;
1092 mode = a_mode;
1093 sha = a_sha;
1094 conf = "file/directory";
1095 } else {
1096 add_branch = branch2;
1097 other_branch = branch1;
1098 mode = b_mode;
1099 sha = b_sha;
1100 conf = "directory/file";
1102 if (path_list_has_path(&current_directory_set, path)) {
1103 const char *new_path = unique_path(path, add_branch);
1104 clean_merge = 0;
1105 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1106 "Added %s as %s",
1107 conf, path, other_branch, path, new_path);
1108 remove_file(0, path, 0);
1109 update_file(0, sha, mode, new_path);
1110 } else {
1111 output(2, "Added %s", path);
1112 update_file(1, sha, mode, path);
1114 } else if (a_sha && b_sha) {
1115 /* Case C: Added in both (check for same permissions) and */
1116 /* case D: Modified in both, but differently. */
1117 const char *reason = "content";
1118 struct merge_file_info mfi;
1119 struct diff_filespec o, a, b;
1121 if (!o_sha) {
1122 reason = "add/add";
1123 o_sha = (unsigned char *)null_sha1;
1125 output(2, "Auto-merged %s", path);
1126 o.path = a.path = b.path = (char *)path;
1127 hashcpy(o.sha1, o_sha);
1128 o.mode = o_mode;
1129 hashcpy(a.sha1, a_sha);
1130 a.mode = a_mode;
1131 hashcpy(b.sha1, b_sha);
1132 b.mode = b_mode;
1134 mfi = merge_file(&o, &a, &b,
1135 branch1, branch2);
1137 clean_merge = mfi.clean;
1138 if (mfi.clean)
1139 update_file(1, mfi.sha, mfi.mode, path);
1140 else if (S_ISGITLINK(mfi.mode))
1141 output(1, "CONFLICT (submodule): Merge conflict in %s "
1142 "- needs %s", path, sha1_to_hex(b.sha1));
1143 else {
1144 output(1, "CONFLICT (%s): Merge conflict in %s",
1145 reason, path);
1147 if (index_only)
1148 update_file(0, mfi.sha, mfi.mode, path);
1149 else
1150 update_file_flags(mfi.sha, mfi.mode, path,
1151 0 /* update_cache */, 1 /* update_working_directory */);
1153 } else if (!o_sha && !a_sha && !b_sha) {
1155 * this entry was deleted altogether. a_mode == 0 means
1156 * we had that path and want to actively remove it.
1158 remove_file(1, path, !a_mode);
1159 } else
1160 die("Fatal merge failure, shouldn't happen.");
1162 return clean_merge;
1165 int merge_trees(struct tree *head,
1166 struct tree *merge,
1167 struct tree *common,
1168 const char *branch1,
1169 const char *branch2,
1170 struct tree **result)
1172 int code, clean;
1174 if (subtree_merge) {
1175 merge = shift_tree_object(head, merge);
1176 common = shift_tree_object(head, common);
1179 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1180 output(0, "Already uptodate!");
1181 *result = head;
1182 return 1;
1185 code = git_merge_trees(index_only, common, head, merge);
1187 if (code != 0)
1188 die("merging of trees %s and %s failed",
1189 sha1_to_hex(head->object.sha1),
1190 sha1_to_hex(merge->object.sha1));
1192 if (unmerged_cache()) {
1193 struct path_list *entries, *re_head, *re_merge;
1194 int i;
1195 path_list_clear(&current_file_set, 1);
1196 path_list_clear(&current_directory_set, 1);
1197 get_files_dirs(head);
1198 get_files_dirs(merge);
1200 entries = get_unmerged();
1201 re_head = get_renames(head, common, head, merge, entries);
1202 re_merge = get_renames(merge, common, head, merge, entries);
1203 clean = process_renames(re_head, re_merge,
1204 branch1, branch2);
1205 for (i = 0; i < entries->nr; i++) {
1206 const char *path = entries->items[i].path;
1207 struct stage_data *e = entries->items[i].util;
1208 if (!e->processed
1209 && !process_entry(path, e, branch1, branch2))
1210 clean = 0;
1213 path_list_clear(re_merge, 0);
1214 path_list_clear(re_head, 0);
1215 path_list_clear(entries, 1);
1218 else
1219 clean = 1;
1221 if (index_only)
1222 *result = write_tree_from_memory();
1224 return clean;
1227 static struct commit_list *reverse_commit_list(struct commit_list *list)
1229 struct commit_list *next = NULL, *current, *backup;
1230 for (current = list; current; current = backup) {
1231 backup = current->next;
1232 current->next = next;
1233 next = current;
1235 return next;
1239 * Merge the commits h1 and h2, return the resulting virtual
1240 * commit object and a flag indicating the cleanness of the merge.
1242 int merge_recursive(struct commit *h1,
1243 struct commit *h2,
1244 const char *branch1,
1245 const char *branch2,
1246 struct commit_list *ca,
1247 struct commit **result)
1249 struct commit_list *iter;
1250 struct commit *merged_common_ancestors;
1251 struct tree *mrtree = mrtree;
1252 int clean;
1254 if (show(4)) {
1255 output(4, "Merging:");
1256 output_commit_title(h1);
1257 output_commit_title(h2);
1260 if (!ca) {
1261 ca = get_merge_bases(h1, h2, 1);
1262 ca = reverse_commit_list(ca);
1265 if (show(5)) {
1266 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1267 for (iter = ca; iter; iter = iter->next)
1268 output_commit_title(iter->item);
1271 merged_common_ancestors = pop_commit(&ca);
1272 if (merged_common_ancestors == NULL) {
1273 /* if there is no common ancestor, make an empty tree */
1274 struct tree *tree = xcalloc(1, sizeof(struct tree));
1276 tree->object.parsed = 1;
1277 tree->object.type = OBJ_TREE;
1278 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1279 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1282 for (iter = ca; iter; iter = iter->next) {
1283 call_depth++;
1285 * When the merge fails, the result contains files
1286 * with conflict markers. The cleanness flag is
1287 * ignored, it was never actually used, as result of
1288 * merge_trees has always overwritten it: the committed
1289 * "conflicts" were already resolved.
1291 discard_cache();
1292 merge_recursive(merged_common_ancestors, iter->item,
1293 "Temporary merge branch 1",
1294 "Temporary merge branch 2",
1295 NULL,
1296 &merged_common_ancestors);
1297 call_depth--;
1299 if (!merged_common_ancestors)
1300 die("merge returned no commit");
1303 discard_cache();
1304 if (!call_depth) {
1305 read_cache();
1306 index_only = 0;
1307 } else
1308 index_only = 1;
1310 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1311 branch1, branch2, &mrtree);
1313 if (index_only) {
1314 *result = make_virtual_commit(mrtree, "merged tree");
1315 commit_list_insert(h1, &(*result)->parents);
1316 commit_list_insert(h2, &(*result)->parents->next);
1318 flush_output();
1319 return clean;
1322 static const char *better_branch_name(const char *branch)
1324 static char githead_env[8 + 40 + 1];
1325 char *name;
1327 if (strlen(branch) != 40)
1328 return branch;
1329 sprintf(githead_env, "GITHEAD_%s", branch);
1330 name = getenv(githead_env);
1331 return name ? name : branch;
1334 static struct commit *get_ref(const char *ref)
1336 unsigned char sha1[20];
1337 struct object *object;
1339 if (get_sha1(ref, sha1))
1340 die("Could not resolve ref '%s'", ref);
1341 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1342 if (!object)
1343 return NULL;
1344 if (object->type == OBJ_TREE)
1345 return make_virtual_commit((struct tree*)object,
1346 better_branch_name(ref));
1347 if (object->type != OBJ_COMMIT)
1348 return NULL;
1349 if (parse_commit((struct commit *)object))
1350 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1351 return (struct commit *)object;
1354 static int merge_config(const char *var, const char *value, void *cb)
1356 if (!strcasecmp(var, "merge.verbosity")) {
1357 verbosity = git_config_int(var, value);
1358 return 0;
1360 if (!strcasecmp(var, "diff.renamelimit")) {
1361 diff_rename_limit = git_config_int(var, value);
1362 return 0;
1364 if (!strcasecmp(var, "merge.renamelimit")) {
1365 merge_rename_limit = git_config_int(var, value);
1366 return 0;
1368 return git_default_config(var, value, cb);
1371 int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
1373 static const char *bases[20];
1374 static unsigned bases_count = 0;
1375 int i, clean;
1376 const char *branch1, *branch2;
1377 struct commit *result, *h1, *h2;
1378 struct commit_list *ca = NULL;
1379 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1380 int index_fd;
1382 if (argv[0]) {
1383 int namelen = strlen(argv[0]);
1384 if (8 < namelen &&
1385 !strcmp(argv[0] + namelen - 8, "-subtree"))
1386 subtree_merge = 1;
1389 git_config(merge_config, NULL);
1390 if (getenv("GIT_MERGE_VERBOSITY"))
1391 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1393 if (argc < 4)
1394 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1396 for (i = 1; i < argc; ++i) {
1397 if (!strcmp(argv[i], "--"))
1398 break;
1399 if (bases_count < sizeof(bases)/sizeof(*bases))
1400 bases[bases_count++] = argv[i];
1402 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1403 die("Not handling anything other than two heads merge.");
1404 if (verbosity >= 5)
1405 buffer_output = 0;
1407 branch1 = argv[++i];
1408 branch2 = argv[++i];
1410 h1 = get_ref(branch1);
1411 h2 = get_ref(branch2);
1413 branch1 = better_branch_name(branch1);
1414 branch2 = better_branch_name(branch2);
1416 if (show(3))
1417 printf("Merging %s with %s\n", branch1, branch2);
1419 index_fd = hold_locked_index(lock, 1);
1421 for (i = 0; i < bases_count; i++) {
1422 struct commit *ancestor = get_ref(bases[i]);
1423 ca = commit_list_insert(ancestor, &ca);
1425 clean = merge_recursive(h1, h2, branch1, branch2, ca, &result);
1427 if (active_cache_changed &&
1428 (write_cache(index_fd, active_cache, active_nr) ||
1429 commit_locked_index(lock)))
1430 die ("unable to write %s", get_index_file());
1432 return clean ? 0: 1;