Start preparing for 1.8.4.2
[alt-git.git] / merge-recursive.c
blobf95933b0aacce84a8b911634e5c40d5e937a322b
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 "advice.h"
7 #include "cache.h"
8 #include "cache-tree.h"
9 #include "commit.h"
10 #include "blob.h"
11 #include "builtin.h"
12 #include "tree-walk.h"
13 #include "diff.h"
14 #include "diffcore.h"
15 #include "tag.h"
16 #include "unpack-trees.h"
17 #include "string-list.h"
18 #include "xdiff-interface.h"
19 #include "ll-merge.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
22 #include "dir.h"
23 #include "submodule.h"
25 static struct tree *shift_tree_object(struct tree *one, struct tree *two,
26 const char *subtree_shift)
28 unsigned char shifted[20];
30 if (!*subtree_shift) {
31 shift_tree(one->object.sha1, two->object.sha1, shifted, 0);
32 } else {
33 shift_tree_by(one->object.sha1, two->object.sha1, shifted,
34 subtree_shift);
36 if (!hashcmp(two->object.sha1, shifted))
37 return two;
38 return lookup_tree(shifted);
41 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
43 struct commit *commit = xcalloc(1, sizeof(struct commit));
44 struct merge_remote_desc *desc = xmalloc(sizeof(*desc));
46 desc->name = comment;
47 desc->obj = (struct object *)commit;
48 commit->tree = tree;
49 commit->util = desc;
50 commit->object.parsed = 1;
51 return commit;
55 * Since we use get_tree_entry(), which does not put the read object into
56 * the object pool, we cannot rely on a == b.
58 static int sha_eq(const unsigned char *a, const unsigned char *b)
60 if (!a && !b)
61 return 2;
62 return a && b && hashcmp(a, b) == 0;
65 enum rename_type {
66 RENAME_NORMAL = 0,
67 RENAME_DELETE,
68 RENAME_ONE_FILE_TO_ONE,
69 RENAME_ONE_FILE_TO_TWO,
70 RENAME_TWO_FILES_TO_ONE
73 struct rename_conflict_info {
74 enum rename_type rename_type;
75 struct diff_filepair *pair1;
76 struct diff_filepair *pair2;
77 const char *branch1;
78 const char *branch2;
79 struct stage_data *dst_entry1;
80 struct stage_data *dst_entry2;
81 struct diff_filespec ren1_other;
82 struct diff_filespec ren2_other;
86 * Since we want to write the index eventually, we cannot reuse the index
87 * for these (temporary) data.
89 struct stage_data {
90 struct {
91 unsigned mode;
92 unsigned char sha[20];
93 } stages[4];
94 struct rename_conflict_info *rename_conflict_info;
95 unsigned processed:1;
98 static inline void setup_rename_conflict_info(enum rename_type rename_type,
99 struct diff_filepair *pair1,
100 struct diff_filepair *pair2,
101 const char *branch1,
102 const char *branch2,
103 struct stage_data *dst_entry1,
104 struct stage_data *dst_entry2,
105 struct merge_options *o,
106 struct stage_data *src_entry1,
107 struct stage_data *src_entry2)
109 struct rename_conflict_info *ci = xcalloc(1, sizeof(struct rename_conflict_info));
110 ci->rename_type = rename_type;
111 ci->pair1 = pair1;
112 ci->branch1 = branch1;
113 ci->branch2 = branch2;
115 ci->dst_entry1 = dst_entry1;
116 dst_entry1->rename_conflict_info = ci;
117 dst_entry1->processed = 0;
119 assert(!pair2 == !dst_entry2);
120 if (dst_entry2) {
121 ci->dst_entry2 = dst_entry2;
122 ci->pair2 = pair2;
123 dst_entry2->rename_conflict_info = ci;
126 if (rename_type == RENAME_TWO_FILES_TO_ONE) {
128 * For each rename, there could have been
129 * modifications on the side of history where that
130 * file was not renamed.
132 int ostage1 = o->branch1 == branch1 ? 3 : 2;
133 int ostage2 = ostage1 ^ 1;
135 ci->ren1_other.path = pair1->one->path;
136 hashcpy(ci->ren1_other.sha1, src_entry1->stages[ostage1].sha);
137 ci->ren1_other.mode = src_entry1->stages[ostage1].mode;
139 ci->ren2_other.path = pair2->one->path;
140 hashcpy(ci->ren2_other.sha1, src_entry2->stages[ostage2].sha);
141 ci->ren2_other.mode = src_entry2->stages[ostage2].mode;
145 static int show(struct merge_options *o, int v)
147 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
150 static void flush_output(struct merge_options *o)
152 if (o->obuf.len) {
153 fputs(o->obuf.buf, stdout);
154 strbuf_reset(&o->obuf);
158 __attribute__((format (printf, 3, 4)))
159 static void output(struct merge_options *o, int v, const char *fmt, ...)
161 va_list ap;
163 if (!show(o, v))
164 return;
166 strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
167 memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
168 strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
170 va_start(ap, fmt);
171 strbuf_vaddf(&o->obuf, fmt, ap);
172 va_end(ap);
174 strbuf_add(&o->obuf, "\n", 1);
175 if (!o->buffer_output)
176 flush_output(o);
179 static void output_commit_title(struct merge_options *o, struct commit *commit)
181 int i;
182 flush_output(o);
183 for (i = o->call_depth; i--;)
184 fputs(" ", stdout);
185 if (commit->util)
186 printf("virtual %s\n", merge_remote_util(commit)->name);
187 else {
188 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
189 if (parse_commit(commit) != 0)
190 printf(_("(bad commit)\n"));
191 else {
192 const char *title;
193 int len = find_commit_subject(commit->buffer, &title);
194 if (len)
195 printf("%.*s\n", len, title);
200 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
201 const char *path, int stage, int refresh, int options)
203 struct cache_entry *ce;
204 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
205 if (!ce)
206 return error(_("addinfo_cache failed for path '%s'"), path);
207 return add_cache_entry(ce, options);
210 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
212 parse_tree(tree);
213 init_tree_desc(desc, tree->buffer, tree->size);
216 static int git_merge_trees(int index_only,
217 struct tree *common,
218 struct tree *head,
219 struct tree *merge)
221 int rc;
222 struct tree_desc t[3];
223 struct unpack_trees_options opts;
225 memset(&opts, 0, sizeof(opts));
226 if (index_only)
227 opts.index_only = 1;
228 else
229 opts.update = 1;
230 opts.merge = 1;
231 opts.head_idx = 2;
232 opts.fn = threeway_merge;
233 opts.src_index = &the_index;
234 opts.dst_index = &the_index;
235 setup_unpack_trees_porcelain(&opts, "merge");
237 init_tree_desc_from_tree(t+0, common);
238 init_tree_desc_from_tree(t+1, head);
239 init_tree_desc_from_tree(t+2, merge);
241 rc = unpack_trees(3, t, &opts);
242 cache_tree_free(&active_cache_tree);
243 return rc;
246 struct tree *write_tree_from_memory(struct merge_options *o)
248 struct tree *result = NULL;
250 if (unmerged_cache()) {
251 int i;
252 fprintf(stderr, "BUG: There are unmerged index entries:\n");
253 for (i = 0; i < active_nr; i++) {
254 const struct cache_entry *ce = active_cache[i];
255 if (ce_stage(ce))
256 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
257 (int)ce_namelen(ce), ce->name);
259 die("Bug in merge-recursive.c");
262 if (!active_cache_tree)
263 active_cache_tree = cache_tree();
265 if (!cache_tree_fully_valid(active_cache_tree) &&
266 cache_tree_update(active_cache_tree,
267 (const struct cache_entry * const *)active_cache,
268 active_nr, 0) < 0)
269 die(_("error building trees"));
271 result = lookup_tree(active_cache_tree->sha1);
273 return result;
276 static int save_files_dirs(const unsigned char *sha1,
277 const char *base, int baselen, const char *path,
278 unsigned int mode, int stage, void *context)
280 int len = strlen(path);
281 char *newpath = xmalloc(baselen + len + 1);
282 struct merge_options *o = context;
284 memcpy(newpath, base, baselen);
285 memcpy(newpath + baselen, path, len);
286 newpath[baselen + len] = '\0';
288 if (S_ISDIR(mode))
289 string_list_insert(&o->current_directory_set, newpath);
290 else
291 string_list_insert(&o->current_file_set, newpath);
292 free(newpath);
294 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
297 static int get_files_dirs(struct merge_options *o, struct tree *tree)
299 int n;
300 struct pathspec match_all;
301 init_pathspec(&match_all, NULL);
302 if (read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o))
303 return 0;
304 n = o->current_file_set.nr + o->current_directory_set.nr;
305 return n;
309 * Returns an index_entry instance which doesn't have to correspond to
310 * a real cache entry in Git's index.
312 static struct stage_data *insert_stage_data(const char *path,
313 struct tree *o, struct tree *a, struct tree *b,
314 struct string_list *entries)
316 struct string_list_item *item;
317 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
318 get_tree_entry(o->object.sha1, path,
319 e->stages[1].sha, &e->stages[1].mode);
320 get_tree_entry(a->object.sha1, path,
321 e->stages[2].sha, &e->stages[2].mode);
322 get_tree_entry(b->object.sha1, path,
323 e->stages[3].sha, &e->stages[3].mode);
324 item = string_list_insert(entries, path);
325 item->util = e;
326 return e;
330 * Create a dictionary mapping file names to stage_data objects. The
331 * dictionary contains one entry for every path with a non-zero stage entry.
333 static struct string_list *get_unmerged(void)
335 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
336 int i;
338 unmerged->strdup_strings = 1;
340 for (i = 0; i < active_nr; i++) {
341 struct string_list_item *item;
342 struct stage_data *e;
343 const struct cache_entry *ce = active_cache[i];
344 if (!ce_stage(ce))
345 continue;
347 item = string_list_lookup(unmerged, ce->name);
348 if (!item) {
349 item = string_list_insert(unmerged, ce->name);
350 item->util = xcalloc(1, sizeof(struct stage_data));
352 e = item->util;
353 e->stages[ce_stage(ce)].mode = ce->ce_mode;
354 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
357 return unmerged;
360 static int string_list_df_name_compare(const void *a, const void *b)
362 const struct string_list_item *one = a;
363 const struct string_list_item *two = b;
364 int onelen = strlen(one->string);
365 int twolen = strlen(two->string);
367 * Here we only care that entries for D/F conflicts are
368 * adjacent, in particular with the file of the D/F conflict
369 * appearing before files below the corresponding directory.
370 * The order of the rest of the list is irrelevant for us.
372 * To achieve this, we sort with df_name_compare and provide
373 * the mode S_IFDIR so that D/F conflicts will sort correctly.
374 * We use the mode S_IFDIR for everything else for simplicity,
375 * since in other cases any changes in their order due to
376 * sorting cause no problems for us.
378 int cmp = df_name_compare(one->string, onelen, S_IFDIR,
379 two->string, twolen, S_IFDIR);
381 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
382 * that 'foo' comes before 'foo/bar'.
384 if (cmp)
385 return cmp;
386 return onelen - twolen;
389 static void record_df_conflict_files(struct merge_options *o,
390 struct string_list *entries)
392 /* If there is a D/F conflict and the file for such a conflict
393 * currently exist in the working tree, we want to allow it to be
394 * removed to make room for the corresponding directory if needed.
395 * The files underneath the directories of such D/F conflicts will
396 * be processed before the corresponding file involved in the D/F
397 * conflict. If the D/F directory ends up being removed by the
398 * merge, then we won't have to touch the D/F file. If the D/F
399 * directory needs to be written to the working copy, then the D/F
400 * file will simply be removed (in make_room_for_path()) to make
401 * room for the necessary paths. Note that if both the directory
402 * and the file need to be present, then the D/F file will be
403 * reinstated with a new unique name at the time it is processed.
405 struct string_list df_sorted_entries;
406 const char *last_file = NULL;
407 int last_len = 0;
408 int i;
411 * If we're merging merge-bases, we don't want to bother with
412 * any working directory changes.
414 if (o->call_depth)
415 return;
417 /* Ensure D/F conflicts are adjacent in the entries list. */
418 memset(&df_sorted_entries, 0, sizeof(struct string_list));
419 for (i = 0; i < entries->nr; i++) {
420 struct string_list_item *next = &entries->items[i];
421 string_list_append(&df_sorted_entries, next->string)->util =
422 next->util;
424 qsort(df_sorted_entries.items, entries->nr, sizeof(*entries->items),
425 string_list_df_name_compare);
427 string_list_clear(&o->df_conflict_file_set, 1);
428 for (i = 0; i < df_sorted_entries.nr; i++) {
429 const char *path = df_sorted_entries.items[i].string;
430 int len = strlen(path);
431 struct stage_data *e = df_sorted_entries.items[i].util;
434 * Check if last_file & path correspond to a D/F conflict;
435 * i.e. whether path is last_file+'/'+<something>.
436 * If so, record that it's okay to remove last_file to make
437 * room for path and friends if needed.
439 if (last_file &&
440 len > last_len &&
441 memcmp(path, last_file, last_len) == 0 &&
442 path[last_len] == '/') {
443 string_list_insert(&o->df_conflict_file_set, last_file);
447 * Determine whether path could exist as a file in the
448 * working directory as a possible D/F conflict. This
449 * will only occur when it exists in stage 2 as a
450 * file.
452 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
453 last_file = path;
454 last_len = len;
455 } else {
456 last_file = NULL;
459 string_list_clear(&df_sorted_entries, 0);
462 struct rename {
463 struct diff_filepair *pair;
464 struct stage_data *src_entry;
465 struct stage_data *dst_entry;
466 unsigned processed:1;
470 * Get information of all renames which occurred between 'o_tree' and
471 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
472 * 'b_tree') to be able to associate the correct cache entries with
473 * the rename information. 'tree' is always equal to either a_tree or b_tree.
475 static struct string_list *get_renames(struct merge_options *o,
476 struct tree *tree,
477 struct tree *o_tree,
478 struct tree *a_tree,
479 struct tree *b_tree,
480 struct string_list *entries)
482 int i;
483 struct string_list *renames;
484 struct diff_options opts;
486 renames = xcalloc(1, sizeof(struct string_list));
487 diff_setup(&opts);
488 DIFF_OPT_SET(&opts, RECURSIVE);
489 DIFF_OPT_CLR(&opts, RENAME_EMPTY);
490 opts.detect_rename = DIFF_DETECT_RENAME;
491 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
492 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
493 1000;
494 opts.rename_score = o->rename_score;
495 opts.show_rename_progress = o->show_rename_progress;
496 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
497 diff_setup_done(&opts);
498 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
499 diffcore_std(&opts);
500 if (opts.needed_rename_limit > o->needed_rename_limit)
501 o->needed_rename_limit = opts.needed_rename_limit;
502 for (i = 0; i < diff_queued_diff.nr; ++i) {
503 struct string_list_item *item;
504 struct rename *re;
505 struct diff_filepair *pair = diff_queued_diff.queue[i];
506 if (pair->status != 'R') {
507 diff_free_filepair(pair);
508 continue;
510 re = xmalloc(sizeof(*re));
511 re->processed = 0;
512 re->pair = pair;
513 item = string_list_lookup(entries, re->pair->one->path);
514 if (!item)
515 re->src_entry = insert_stage_data(re->pair->one->path,
516 o_tree, a_tree, b_tree, entries);
517 else
518 re->src_entry = item->util;
520 item = string_list_lookup(entries, re->pair->two->path);
521 if (!item)
522 re->dst_entry = insert_stage_data(re->pair->two->path,
523 o_tree, a_tree, b_tree, entries);
524 else
525 re->dst_entry = item->util;
526 item = string_list_insert(renames, pair->one->path);
527 item->util = re;
529 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
530 diff_queued_diff.nr = 0;
531 diff_flush(&opts);
532 return renames;
535 static int update_stages(const char *path, const struct diff_filespec *o,
536 const struct diff_filespec *a,
537 const struct diff_filespec *b)
541 * NOTE: It is usually a bad idea to call update_stages on a path
542 * before calling update_file on that same path, since it can
543 * sometimes lead to spurious "refusing to lose untracked file..."
544 * messages from update_file (via make_room_for path via
545 * would_lose_untracked). Instead, reverse the order of the calls
546 * (executing update_file first and then update_stages).
548 int clear = 1;
549 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
550 if (clear)
551 if (remove_file_from_cache(path))
552 return -1;
553 if (o)
554 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
555 return -1;
556 if (a)
557 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
558 return -1;
559 if (b)
560 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
561 return -1;
562 return 0;
565 static void update_entry(struct stage_data *entry,
566 struct diff_filespec *o,
567 struct diff_filespec *a,
568 struct diff_filespec *b)
570 entry->processed = 0;
571 entry->stages[1].mode = o->mode;
572 entry->stages[2].mode = a->mode;
573 entry->stages[3].mode = b->mode;
574 hashcpy(entry->stages[1].sha, o->sha1);
575 hashcpy(entry->stages[2].sha, a->sha1);
576 hashcpy(entry->stages[3].sha, b->sha1);
579 static int remove_file(struct merge_options *o, int clean,
580 const char *path, int no_wd)
582 int update_cache = o->call_depth || clean;
583 int update_working_directory = !o->call_depth && !no_wd;
585 if (update_cache) {
586 if (remove_file_from_cache(path))
587 return -1;
589 if (update_working_directory) {
590 if (remove_path(path))
591 return -1;
593 return 0;
596 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
598 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
599 int suffix = 0;
600 struct stat st;
601 char *p = newpath + strlen(path);
602 strcpy(newpath, path);
603 *(p++) = '~';
604 strcpy(p, branch);
605 for (; *p; ++p)
606 if ('/' == *p)
607 *p = '_';
608 while (string_list_has_string(&o->current_file_set, newpath) ||
609 string_list_has_string(&o->current_directory_set, newpath) ||
610 lstat(newpath, &st) == 0)
611 sprintf(p, "_%d", suffix++);
613 string_list_insert(&o->current_file_set, newpath);
614 return newpath;
617 static int dir_in_way(const char *path, int check_working_copy)
619 int pos, pathlen = strlen(path);
620 char *dirpath = xmalloc(pathlen + 2);
621 struct stat st;
623 strcpy(dirpath, path);
624 dirpath[pathlen] = '/';
625 dirpath[pathlen+1] = '\0';
627 pos = cache_name_pos(dirpath, pathlen+1);
629 if (pos < 0)
630 pos = -1 - pos;
631 if (pos < active_nr &&
632 !strncmp(dirpath, active_cache[pos]->name, pathlen+1)) {
633 free(dirpath);
634 return 1;
637 free(dirpath);
638 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode);
641 static int was_tracked(const char *path)
643 int pos = cache_name_pos(path, strlen(path));
645 if (pos < 0)
646 pos = -1 - pos;
647 while (pos < active_nr &&
648 !strcmp(path, active_cache[pos]->name)) {
650 * If stage #0, it is definitely tracked.
651 * If it has stage #2 then it was tracked
652 * before this merge started. All other
653 * cases the path was not tracked.
655 switch (ce_stage(active_cache[pos])) {
656 case 0:
657 case 2:
658 return 1;
660 pos++;
662 return 0;
665 static int would_lose_untracked(const char *path)
667 return !was_tracked(path) && file_exists(path);
670 static int make_room_for_path(struct merge_options *o, const char *path)
672 int status, i;
673 const char *msg = _("failed to create path '%s'%s");
675 /* Unlink any D/F conflict files that are in the way */
676 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
677 const char *df_path = o->df_conflict_file_set.items[i].string;
678 size_t pathlen = strlen(path);
679 size_t df_pathlen = strlen(df_path);
680 if (df_pathlen < pathlen &&
681 path[df_pathlen] == '/' &&
682 strncmp(path, df_path, df_pathlen) == 0) {
683 output(o, 3,
684 _("Removing %s to make room for subdirectory\n"),
685 df_path);
686 unlink(df_path);
687 unsorted_string_list_delete_item(&o->df_conflict_file_set,
688 i, 0);
689 break;
693 /* Make sure leading directories are created */
694 status = safe_create_leading_directories_const(path);
695 if (status) {
696 if (status == -3) {
697 /* something else exists */
698 error(msg, path, _(": perhaps a D/F conflict?"));
699 return -1;
701 die(msg, path, "");
705 * Do not unlink a file in the work tree if we are not
706 * tracking it.
708 if (would_lose_untracked(path))
709 return error(_("refusing to lose untracked file at '%s'"),
710 path);
712 /* Successful unlink is good.. */
713 if (!unlink(path))
714 return 0;
715 /* .. and so is no existing file */
716 if (errno == ENOENT)
717 return 0;
718 /* .. but not some other error (who really cares what?) */
719 return error(msg, path, _(": perhaps a D/F conflict?"));
722 static void update_file_flags(struct merge_options *o,
723 const unsigned char *sha,
724 unsigned mode,
725 const char *path,
726 int update_cache,
727 int update_wd)
729 if (o->call_depth)
730 update_wd = 0;
732 if (update_wd) {
733 enum object_type type;
734 void *buf;
735 unsigned long size;
737 if (S_ISGITLINK(mode)) {
739 * We may later decide to recursively descend into
740 * the submodule directory and update its index
741 * and/or work tree, but we do not do that now.
743 update_wd = 0;
744 goto update_index;
747 buf = read_sha1_file(sha, &type, &size);
748 if (!buf)
749 die(_("cannot read object %s '%s'"), sha1_to_hex(sha), path);
750 if (type != OBJ_BLOB)
751 die(_("blob expected for %s '%s'"), sha1_to_hex(sha), path);
752 if (S_ISREG(mode)) {
753 struct strbuf strbuf = STRBUF_INIT;
754 if (convert_to_working_tree(path, buf, size, &strbuf)) {
755 free(buf);
756 size = strbuf.len;
757 buf = strbuf_detach(&strbuf, NULL);
761 if (make_room_for_path(o, path) < 0) {
762 update_wd = 0;
763 free(buf);
764 goto update_index;
766 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
767 int fd;
768 if (mode & 0100)
769 mode = 0777;
770 else
771 mode = 0666;
772 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
773 if (fd < 0)
774 die_errno(_("failed to open '%s'"), path);
775 write_in_full(fd, buf, size);
776 close(fd);
777 } else if (S_ISLNK(mode)) {
778 char *lnk = xmemdupz(buf, size);
779 safe_create_leading_directories_const(path);
780 unlink(path);
781 if (symlink(lnk, path))
782 die_errno(_("failed to symlink '%s'"), path);
783 free(lnk);
784 } else
785 die(_("do not know what to do with %06o %s '%s'"),
786 mode, sha1_to_hex(sha), path);
787 free(buf);
789 update_index:
790 if (update_cache)
791 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
794 static void update_file(struct merge_options *o,
795 int clean,
796 const unsigned char *sha,
797 unsigned mode,
798 const char *path)
800 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
803 /* Low level file merging, update and removal */
805 struct merge_file_info {
806 unsigned char sha[20];
807 unsigned mode;
808 unsigned clean:1,
809 merge:1;
812 static int merge_3way(struct merge_options *o,
813 mmbuffer_t *result_buf,
814 const struct diff_filespec *one,
815 const struct diff_filespec *a,
816 const struct diff_filespec *b,
817 const char *branch1,
818 const char *branch2)
820 mmfile_t orig, src1, src2;
821 struct ll_merge_options ll_opts = {0};
822 char *base_name, *name1, *name2;
823 int merge_status;
825 ll_opts.renormalize = o->renormalize;
826 ll_opts.xdl_opts = o->xdl_opts;
828 if (o->call_depth) {
829 ll_opts.virtual_ancestor = 1;
830 ll_opts.variant = 0;
831 } else {
832 switch (o->recursive_variant) {
833 case MERGE_RECURSIVE_OURS:
834 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
835 break;
836 case MERGE_RECURSIVE_THEIRS:
837 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
838 break;
839 default:
840 ll_opts.variant = 0;
841 break;
845 if (strcmp(a->path, b->path) ||
846 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
847 base_name = o->ancestor == NULL ? NULL :
848 mkpathdup("%s:%s", o->ancestor, one->path);
849 name1 = mkpathdup("%s:%s", branch1, a->path);
850 name2 = mkpathdup("%s:%s", branch2, b->path);
851 } else {
852 base_name = o->ancestor == NULL ? NULL :
853 mkpathdup("%s", o->ancestor);
854 name1 = mkpathdup("%s", branch1);
855 name2 = mkpathdup("%s", branch2);
858 read_mmblob(&orig, one->sha1);
859 read_mmblob(&src1, a->sha1);
860 read_mmblob(&src2, b->sha1);
862 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
863 &src1, name1, &src2, name2, &ll_opts);
865 free(base_name);
866 free(name1);
867 free(name2);
868 free(orig.ptr);
869 free(src1.ptr);
870 free(src2.ptr);
871 return merge_status;
874 static struct merge_file_info merge_file_1(struct merge_options *o,
875 const struct diff_filespec *one,
876 const struct diff_filespec *a,
877 const struct diff_filespec *b,
878 const char *branch1,
879 const char *branch2)
881 struct merge_file_info result;
882 result.merge = 0;
883 result.clean = 1;
885 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
886 result.clean = 0;
887 if (S_ISREG(a->mode)) {
888 result.mode = a->mode;
889 hashcpy(result.sha, a->sha1);
890 } else {
891 result.mode = b->mode;
892 hashcpy(result.sha, b->sha1);
894 } else {
895 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
896 result.merge = 1;
899 * Merge modes
901 if (a->mode == b->mode || a->mode == one->mode)
902 result.mode = b->mode;
903 else {
904 result.mode = a->mode;
905 if (b->mode != one->mode) {
906 result.clean = 0;
907 result.merge = 1;
911 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
912 hashcpy(result.sha, b->sha1);
913 else if (sha_eq(b->sha1, one->sha1))
914 hashcpy(result.sha, a->sha1);
915 else if (S_ISREG(a->mode)) {
916 mmbuffer_t result_buf;
917 int merge_status;
919 merge_status = merge_3way(o, &result_buf, one, a, b,
920 branch1, branch2);
922 if ((merge_status < 0) || !result_buf.ptr)
923 die(_("Failed to execute internal merge"));
925 if (write_sha1_file(result_buf.ptr, result_buf.size,
926 blob_type, result.sha))
927 die(_("Unable to add %s to database"),
928 a->path);
930 free(result_buf.ptr);
931 result.clean = (merge_status == 0);
932 } else if (S_ISGITLINK(a->mode)) {
933 result.clean = merge_submodule(result.sha,
934 one->path, one->sha1,
935 a->sha1, b->sha1,
936 !o->call_depth);
937 } else if (S_ISLNK(a->mode)) {
938 hashcpy(result.sha, a->sha1);
940 if (!sha_eq(a->sha1, b->sha1))
941 result.clean = 0;
942 } else {
943 die(_("unsupported object type in the tree"));
947 return result;
950 static struct merge_file_info
951 merge_file_special_markers(struct merge_options *o,
952 const struct diff_filespec *one,
953 const struct diff_filespec *a,
954 const struct diff_filespec *b,
955 const char *branch1,
956 const char *filename1,
957 const char *branch2,
958 const char *filename2)
960 char *side1 = NULL;
961 char *side2 = NULL;
962 struct merge_file_info mfi;
964 if (filename1) {
965 side1 = xmalloc(strlen(branch1) + strlen(filename1) + 2);
966 sprintf(side1, "%s:%s", branch1, filename1);
968 if (filename2) {
969 side2 = xmalloc(strlen(branch2) + strlen(filename2) + 2);
970 sprintf(side2, "%s:%s", branch2, filename2);
973 mfi = merge_file_1(o, one, a, b,
974 side1 ? side1 : branch1, side2 ? side2 : branch2);
975 free(side1);
976 free(side2);
977 return mfi;
980 static struct merge_file_info merge_file_one(struct merge_options *o,
981 const char *path,
982 const unsigned char *o_sha, int o_mode,
983 const unsigned char *a_sha, int a_mode,
984 const unsigned char *b_sha, int b_mode,
985 const char *branch1,
986 const char *branch2)
988 struct diff_filespec one, a, b;
990 one.path = a.path = b.path = (char *)path;
991 hashcpy(one.sha1, o_sha);
992 one.mode = o_mode;
993 hashcpy(a.sha1, a_sha);
994 a.mode = a_mode;
995 hashcpy(b.sha1, b_sha);
996 b.mode = b_mode;
997 return merge_file_1(o, &one, &a, &b, branch1, branch2);
1000 static void handle_change_delete(struct merge_options *o,
1001 const char *path,
1002 const unsigned char *o_sha, int o_mode,
1003 const unsigned char *a_sha, int a_mode,
1004 const unsigned char *b_sha, int b_mode,
1005 const char *change, const char *change_past)
1007 char *renamed = NULL;
1008 if (dir_in_way(path, !o->call_depth)) {
1009 renamed = unique_path(o, path, a_sha ? o->branch1 : o->branch2);
1012 if (o->call_depth) {
1014 * We cannot arbitrarily accept either a_sha or b_sha as
1015 * correct; since there is no true "middle point" between
1016 * them, simply reuse the base version for virtual merge base.
1018 remove_file_from_cache(path);
1019 update_file(o, 0, o_sha, o_mode, renamed ? renamed : path);
1020 } else if (!a_sha) {
1021 if (!renamed) {
1022 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1023 "and %s in %s. Version %s of %s left in tree."),
1024 change, path, o->branch1, change_past,
1025 o->branch2, o->branch2, path);
1026 update_file(o, 0, b_sha, b_mode, path);
1027 } else {
1028 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1029 "and %s in %s. Version %s of %s left in tree at %s."),
1030 change, path, o->branch1, change_past,
1031 o->branch2, o->branch2, path, renamed);
1032 update_file(o, 0, b_sha, b_mode, renamed);
1034 } else {
1035 if (!renamed) {
1036 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1037 "and %s in %s. Version %s of %s left in tree."),
1038 change, path, o->branch2, change_past,
1039 o->branch1, o->branch1, path);
1040 } else {
1041 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1042 "and %s in %s. Version %s of %s left in tree at %s."),
1043 change, path, o->branch2, change_past,
1044 o->branch1, o->branch1, path, renamed);
1045 update_file(o, 0, a_sha, a_mode, renamed);
1048 * No need to call update_file() on path when !renamed, since
1049 * that would needlessly touch path. We could call
1050 * update_file_flags() with update_cache=0 and update_wd=0,
1051 * but that's a no-op.
1054 free(renamed);
1057 static void conflict_rename_delete(struct merge_options *o,
1058 struct diff_filepair *pair,
1059 const char *rename_branch,
1060 const char *other_branch)
1062 const struct diff_filespec *orig = pair->one;
1063 const struct diff_filespec *dest = pair->two;
1064 const unsigned char *a_sha = NULL;
1065 const unsigned char *b_sha = NULL;
1066 int a_mode = 0;
1067 int b_mode = 0;
1069 if (rename_branch == o->branch1) {
1070 a_sha = dest->sha1;
1071 a_mode = dest->mode;
1072 } else {
1073 b_sha = dest->sha1;
1074 b_mode = dest->mode;
1077 handle_change_delete(o,
1078 o->call_depth ? orig->path : dest->path,
1079 orig->sha1, orig->mode,
1080 a_sha, a_mode,
1081 b_sha, b_mode,
1082 _("rename"), _("renamed"));
1084 if (o->call_depth) {
1085 remove_file_from_cache(dest->path);
1086 } else {
1087 update_stages(dest->path, NULL,
1088 rename_branch == o->branch1 ? dest : NULL,
1089 rename_branch == o->branch1 ? NULL : dest);
1094 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1095 struct stage_data *entry,
1096 int stage)
1098 unsigned char *sha = entry->stages[stage].sha;
1099 unsigned mode = entry->stages[stage].mode;
1100 if (mode == 0 || is_null_sha1(sha))
1101 return NULL;
1102 hashcpy(target->sha1, sha);
1103 target->mode = mode;
1104 return target;
1107 static void handle_file(struct merge_options *o,
1108 struct diff_filespec *rename,
1109 int stage,
1110 struct rename_conflict_info *ci)
1112 char *dst_name = rename->path;
1113 struct stage_data *dst_entry;
1114 const char *cur_branch, *other_branch;
1115 struct diff_filespec other;
1116 struct diff_filespec *add;
1118 if (stage == 2) {
1119 dst_entry = ci->dst_entry1;
1120 cur_branch = ci->branch1;
1121 other_branch = ci->branch2;
1122 } else {
1123 dst_entry = ci->dst_entry2;
1124 cur_branch = ci->branch2;
1125 other_branch = ci->branch1;
1128 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1129 if (add) {
1130 char *add_name = unique_path(o, rename->path, other_branch);
1131 update_file(o, 0, add->sha1, add->mode, add_name);
1133 remove_file(o, 0, rename->path, 0);
1134 dst_name = unique_path(o, rename->path, cur_branch);
1135 } else {
1136 if (dir_in_way(rename->path, !o->call_depth)) {
1137 dst_name = unique_path(o, rename->path, cur_branch);
1138 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1139 rename->path, other_branch, dst_name);
1142 update_file(o, 0, rename->sha1, rename->mode, dst_name);
1143 if (stage == 2)
1144 update_stages(rename->path, NULL, rename, add);
1145 else
1146 update_stages(rename->path, NULL, add, rename);
1148 if (dst_name != rename->path)
1149 free(dst_name);
1152 static void conflict_rename_rename_1to2(struct merge_options *o,
1153 struct rename_conflict_info *ci)
1155 /* One file was renamed in both branches, but to different names. */
1156 struct diff_filespec *one = ci->pair1->one;
1157 struct diff_filespec *a = ci->pair1->two;
1158 struct diff_filespec *b = ci->pair2->two;
1160 output(o, 1, _("CONFLICT (rename/rename): "
1161 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1162 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1163 one->path, a->path, ci->branch1,
1164 one->path, b->path, ci->branch2,
1165 o->call_depth ? _(" (left unresolved)") : "");
1166 if (o->call_depth) {
1167 struct merge_file_info mfi;
1168 struct diff_filespec other;
1169 struct diff_filespec *add;
1170 mfi = merge_file_one(o, one->path,
1171 one->sha1, one->mode,
1172 a->sha1, a->mode,
1173 b->sha1, b->mode,
1174 ci->branch1, ci->branch2);
1176 * FIXME: For rename/add-source conflicts (if we could detect
1177 * such), this is wrong. We should instead find a unique
1178 * pathname and then either rename the add-source file to that
1179 * unique path, or use that unique path instead of src here.
1181 update_file(o, 0, mfi.sha, mfi.mode, one->path);
1184 * Above, we put the merged content at the merge-base's
1185 * path. Now we usually need to delete both a->path and
1186 * b->path. However, the rename on each side of the merge
1187 * could also be involved in a rename/add conflict. In
1188 * such cases, we should keep the added file around,
1189 * resolving the conflict at that path in its favor.
1191 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1192 if (add)
1193 update_file(o, 0, add->sha1, add->mode, a->path);
1194 else
1195 remove_file_from_cache(a->path);
1196 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1197 if (add)
1198 update_file(o, 0, add->sha1, add->mode, b->path);
1199 else
1200 remove_file_from_cache(b->path);
1201 } else {
1202 handle_file(o, a, 2, ci);
1203 handle_file(o, b, 3, ci);
1207 static void conflict_rename_rename_2to1(struct merge_options *o,
1208 struct rename_conflict_info *ci)
1210 /* Two files, a & b, were renamed to the same thing, c. */
1211 struct diff_filespec *a = ci->pair1->one;
1212 struct diff_filespec *b = ci->pair2->one;
1213 struct diff_filespec *c1 = ci->pair1->two;
1214 struct diff_filespec *c2 = ci->pair2->two;
1215 char *path = c1->path; /* == c2->path */
1216 struct merge_file_info mfi_c1;
1217 struct merge_file_info mfi_c2;
1219 output(o, 1, _("CONFLICT (rename/rename): "
1220 "Rename %s->%s in %s. "
1221 "Rename %s->%s in %s"),
1222 a->path, c1->path, ci->branch1,
1223 b->path, c2->path, ci->branch2);
1225 remove_file(o, 1, a->path, would_lose_untracked(a->path));
1226 remove_file(o, 1, b->path, would_lose_untracked(b->path));
1228 mfi_c1 = merge_file_special_markers(o, a, c1, &ci->ren1_other,
1229 o->branch1, c1->path,
1230 o->branch2, ci->ren1_other.path);
1231 mfi_c2 = merge_file_special_markers(o, b, &ci->ren2_other, c2,
1232 o->branch1, ci->ren2_other.path,
1233 o->branch2, c2->path);
1235 if (o->call_depth) {
1237 * If mfi_c1.clean && mfi_c2.clean, then it might make
1238 * sense to do a two-way merge of those results. But, I
1239 * think in all cases, it makes sense to have the virtual
1240 * merge base just undo the renames; they can be detected
1241 * again later for the non-recursive merge.
1243 remove_file(o, 0, path, 0);
1244 update_file(o, 0, mfi_c1.sha, mfi_c1.mode, a->path);
1245 update_file(o, 0, mfi_c2.sha, mfi_c2.mode, b->path);
1246 } else {
1247 char *new_path1 = unique_path(o, path, ci->branch1);
1248 char *new_path2 = unique_path(o, path, ci->branch2);
1249 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1250 a->path, new_path1, b->path, new_path2);
1251 remove_file(o, 0, path, 0);
1252 update_file(o, 0, mfi_c1.sha, mfi_c1.mode, new_path1);
1253 update_file(o, 0, mfi_c2.sha, mfi_c2.mode, new_path2);
1254 free(new_path2);
1255 free(new_path1);
1259 static int process_renames(struct merge_options *o,
1260 struct string_list *a_renames,
1261 struct string_list *b_renames)
1263 int clean_merge = 1, i, j;
1264 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
1265 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
1266 const struct rename *sre;
1268 for (i = 0; i < a_renames->nr; i++) {
1269 sre = a_renames->items[i].util;
1270 string_list_insert(&a_by_dst, sre->pair->two->path)->util
1271 = (void *)sre;
1273 for (i = 0; i < b_renames->nr; i++) {
1274 sre = b_renames->items[i].util;
1275 string_list_insert(&b_by_dst, sre->pair->two->path)->util
1276 = (void *)sre;
1279 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1280 struct string_list *renames1, *renames2Dst;
1281 struct rename *ren1 = NULL, *ren2 = NULL;
1282 const char *branch1, *branch2;
1283 const char *ren1_src, *ren1_dst;
1284 struct string_list_item *lookup;
1286 if (i >= a_renames->nr) {
1287 ren2 = b_renames->items[j++].util;
1288 } else if (j >= b_renames->nr) {
1289 ren1 = a_renames->items[i++].util;
1290 } else {
1291 int compare = strcmp(a_renames->items[i].string,
1292 b_renames->items[j].string);
1293 if (compare <= 0)
1294 ren1 = a_renames->items[i++].util;
1295 if (compare >= 0)
1296 ren2 = b_renames->items[j++].util;
1299 /* TODO: refactor, so that 1/2 are not needed */
1300 if (ren1) {
1301 renames1 = a_renames;
1302 renames2Dst = &b_by_dst;
1303 branch1 = o->branch1;
1304 branch2 = o->branch2;
1305 } else {
1306 struct rename *tmp;
1307 renames1 = b_renames;
1308 renames2Dst = &a_by_dst;
1309 branch1 = o->branch2;
1310 branch2 = o->branch1;
1311 tmp = ren2;
1312 ren2 = ren1;
1313 ren1 = tmp;
1316 if (ren1->processed)
1317 continue;
1318 ren1->processed = 1;
1319 ren1->dst_entry->processed = 1;
1320 /* BUG: We should only mark src_entry as processed if we
1321 * are not dealing with a rename + add-source case.
1323 ren1->src_entry->processed = 1;
1325 ren1_src = ren1->pair->one->path;
1326 ren1_dst = ren1->pair->two->path;
1328 if (ren2) {
1329 /* One file renamed on both sides */
1330 const char *ren2_src = ren2->pair->one->path;
1331 const char *ren2_dst = ren2->pair->two->path;
1332 enum rename_type rename_type;
1333 if (strcmp(ren1_src, ren2_src) != 0)
1334 die("ren1_src != ren2_src");
1335 ren2->dst_entry->processed = 1;
1336 ren2->processed = 1;
1337 if (strcmp(ren1_dst, ren2_dst) != 0) {
1338 rename_type = RENAME_ONE_FILE_TO_TWO;
1339 clean_merge = 0;
1340 } else {
1341 rename_type = RENAME_ONE_FILE_TO_ONE;
1342 /* BUG: We should only remove ren1_src in
1343 * the base stage (think of rename +
1344 * add-source cases).
1346 remove_file(o, 1, ren1_src, 1);
1347 update_entry(ren1->dst_entry,
1348 ren1->pair->one,
1349 ren1->pair->two,
1350 ren2->pair->two);
1352 setup_rename_conflict_info(rename_type,
1353 ren1->pair,
1354 ren2->pair,
1355 branch1,
1356 branch2,
1357 ren1->dst_entry,
1358 ren2->dst_entry,
1360 NULL,
1361 NULL);
1362 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
1363 /* Two different files renamed to the same thing */
1364 char *ren2_dst;
1365 ren2 = lookup->util;
1366 ren2_dst = ren2->pair->two->path;
1367 if (strcmp(ren1_dst, ren2_dst) != 0)
1368 die("ren1_dst != ren2_dst");
1370 clean_merge = 0;
1371 ren2->processed = 1;
1373 * BUG: We should only mark src_entry as processed
1374 * if we are not dealing with a rename + add-source
1375 * case.
1377 ren2->src_entry->processed = 1;
1379 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
1380 ren1->pair,
1381 ren2->pair,
1382 branch1,
1383 branch2,
1384 ren1->dst_entry,
1385 ren2->dst_entry,
1387 ren1->src_entry,
1388 ren2->src_entry);
1390 } else {
1391 /* Renamed in 1, maybe changed in 2 */
1392 /* we only use sha1 and mode of these */
1393 struct diff_filespec src_other, dst_other;
1394 int try_merge;
1397 * unpack_trees loads entries from common-commit
1398 * into stage 1, from head-commit into stage 2, and
1399 * from merge-commit into stage 3. We keep track
1400 * of which side corresponds to the rename.
1402 int renamed_stage = a_renames == renames1 ? 2 : 3;
1403 int other_stage = a_renames == renames1 ? 3 : 2;
1405 /* BUG: We should only remove ren1_src in the base
1406 * stage and in other_stage (think of rename +
1407 * add-source case).
1409 remove_file(o, 1, ren1_src,
1410 renamed_stage == 2 || !was_tracked(ren1_src));
1412 hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
1413 src_other.mode = ren1->src_entry->stages[other_stage].mode;
1414 hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
1415 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1416 try_merge = 0;
1418 if (sha_eq(src_other.sha1, null_sha1)) {
1419 setup_rename_conflict_info(RENAME_DELETE,
1420 ren1->pair,
1421 NULL,
1422 branch1,
1423 branch2,
1424 ren1->dst_entry,
1425 NULL,
1427 NULL,
1428 NULL);
1429 } else if ((dst_other.mode == ren1->pair->two->mode) &&
1430 sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
1432 * Added file on the other side identical to
1433 * the file being renamed: clean merge.
1434 * Also, there is no need to overwrite the
1435 * file already in the working copy, so call
1436 * update_file_flags() instead of
1437 * update_file().
1439 update_file_flags(o,
1440 ren1->pair->two->sha1,
1441 ren1->pair->two->mode,
1442 ren1_dst,
1443 1, /* update_cache */
1444 0 /* update_wd */);
1445 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1446 clean_merge = 0;
1447 try_merge = 1;
1448 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
1449 "%s added in %s"),
1450 ren1_src, ren1_dst, branch1,
1451 ren1_dst, branch2);
1452 if (o->call_depth) {
1453 struct merge_file_info mfi;
1454 mfi = merge_file_one(o, ren1_dst, null_sha1, 0,
1455 ren1->pair->two->sha1, ren1->pair->two->mode,
1456 dst_other.sha1, dst_other.mode,
1457 branch1, branch2);
1458 output(o, 1, _("Adding merged %s"), ren1_dst);
1459 update_file(o, 0, mfi.sha, mfi.mode, ren1_dst);
1460 try_merge = 0;
1461 } else {
1462 char *new_path = unique_path(o, ren1_dst, branch2);
1463 output(o, 1, _("Adding as %s instead"), new_path);
1464 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
1465 free(new_path);
1467 } else
1468 try_merge = 1;
1470 if (try_merge) {
1471 struct diff_filespec *one, *a, *b;
1472 src_other.path = (char *)ren1_src;
1474 one = ren1->pair->one;
1475 if (a_renames == renames1) {
1476 a = ren1->pair->two;
1477 b = &src_other;
1478 } else {
1479 b = ren1->pair->two;
1480 a = &src_other;
1482 update_entry(ren1->dst_entry, one, a, b);
1483 setup_rename_conflict_info(RENAME_NORMAL,
1484 ren1->pair,
1485 NULL,
1486 branch1,
1487 NULL,
1488 ren1->dst_entry,
1489 NULL,
1491 NULL,
1492 NULL);
1496 string_list_clear(&a_by_dst, 0);
1497 string_list_clear(&b_by_dst, 0);
1499 return clean_merge;
1502 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1504 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1507 static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1509 void *buf;
1510 enum object_type type;
1511 unsigned long size;
1512 buf = read_sha1_file(sha1, &type, &size);
1513 if (!buf)
1514 return error(_("cannot read object %s"), sha1_to_hex(sha1));
1515 if (type != OBJ_BLOB) {
1516 free(buf);
1517 return error(_("object %s is not a blob"), sha1_to_hex(sha1));
1519 strbuf_attach(dst, buf, size, size + 1);
1520 return 0;
1523 static int blob_unchanged(const unsigned char *o_sha,
1524 const unsigned char *a_sha,
1525 int renormalize, const char *path)
1527 struct strbuf o = STRBUF_INIT;
1528 struct strbuf a = STRBUF_INIT;
1529 int ret = 0; /* assume changed for safety */
1531 if (sha_eq(o_sha, a_sha))
1532 return 1;
1533 if (!renormalize)
1534 return 0;
1536 assert(o_sha && a_sha);
1537 if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1538 goto error_return;
1540 * Note: binary | is used so that both renormalizations are
1541 * performed. Comparison can be skipped if both files are
1542 * unchanged since their sha1s have already been compared.
1544 if (renormalize_buffer(path, o.buf, o.len, &o) |
1545 renormalize_buffer(path, a.buf, o.len, &a))
1546 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1548 error_return:
1549 strbuf_release(&o);
1550 strbuf_release(&a);
1551 return ret;
1554 static void handle_modify_delete(struct merge_options *o,
1555 const char *path,
1556 unsigned char *o_sha, int o_mode,
1557 unsigned char *a_sha, int a_mode,
1558 unsigned char *b_sha, int b_mode)
1560 handle_change_delete(o,
1561 path,
1562 o_sha, o_mode,
1563 a_sha, a_mode,
1564 b_sha, b_mode,
1565 _("modify"), _("modified"));
1568 static int merge_content(struct merge_options *o,
1569 const char *path,
1570 unsigned char *o_sha, int o_mode,
1571 unsigned char *a_sha, int a_mode,
1572 unsigned char *b_sha, int b_mode,
1573 struct rename_conflict_info *rename_conflict_info)
1575 const char *reason = _("content");
1576 const char *path1 = NULL, *path2 = NULL;
1577 struct merge_file_info mfi;
1578 struct diff_filespec one, a, b;
1579 unsigned df_conflict_remains = 0;
1581 if (!o_sha) {
1582 reason = _("add/add");
1583 o_sha = (unsigned char *)null_sha1;
1585 one.path = a.path = b.path = (char *)path;
1586 hashcpy(one.sha1, o_sha);
1587 one.mode = o_mode;
1588 hashcpy(a.sha1, a_sha);
1589 a.mode = a_mode;
1590 hashcpy(b.sha1, b_sha);
1591 b.mode = b_mode;
1593 if (rename_conflict_info) {
1594 struct diff_filepair *pair1 = rename_conflict_info->pair1;
1596 path1 = (o->branch1 == rename_conflict_info->branch1) ?
1597 pair1->two->path : pair1->one->path;
1598 /* If rename_conflict_info->pair2 != NULL, we are in
1599 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
1600 * normal rename.
1602 path2 = (rename_conflict_info->pair2 ||
1603 o->branch2 == rename_conflict_info->branch1) ?
1604 pair1->two->path : pair1->one->path;
1606 if (dir_in_way(path, !o->call_depth))
1607 df_conflict_remains = 1;
1609 mfi = merge_file_special_markers(o, &one, &a, &b,
1610 o->branch1, path1,
1611 o->branch2, path2);
1613 if (mfi.clean && !df_conflict_remains &&
1614 sha_eq(mfi.sha, a_sha) && mfi.mode == a_mode) {
1615 int path_renamed_outside_HEAD;
1616 output(o, 3, _("Skipped %s (merged same as existing)"), path);
1618 * The content merge resulted in the same file contents we
1619 * already had. We can return early if those file contents
1620 * are recorded at the correct path (which may not be true
1621 * if the merge involves a rename).
1623 path_renamed_outside_HEAD = !path2 || !strcmp(path, path2);
1624 if (!path_renamed_outside_HEAD) {
1625 add_cacheinfo(mfi.mode, mfi.sha, path,
1626 0, (!o->call_depth), 0);
1627 return mfi.clean;
1629 } else
1630 output(o, 2, _("Auto-merging %s"), path);
1632 if (!mfi.clean) {
1633 if (S_ISGITLINK(mfi.mode))
1634 reason = _("submodule");
1635 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
1636 reason, path);
1637 if (rename_conflict_info && !df_conflict_remains)
1638 update_stages(path, &one, &a, &b);
1641 if (df_conflict_remains) {
1642 char *new_path;
1643 if (o->call_depth) {
1644 remove_file_from_cache(path);
1645 } else {
1646 if (!mfi.clean)
1647 update_stages(path, &one, &a, &b);
1648 else {
1649 int file_from_stage2 = was_tracked(path);
1650 struct diff_filespec merged;
1651 hashcpy(merged.sha1, mfi.sha);
1652 merged.mode = mfi.mode;
1654 update_stages(path, NULL,
1655 file_from_stage2 ? &merged : NULL,
1656 file_from_stage2 ? NULL : &merged);
1660 new_path = unique_path(o, path, rename_conflict_info->branch1);
1661 output(o, 1, _("Adding as %s instead"), new_path);
1662 update_file(o, 0, mfi.sha, mfi.mode, new_path);
1663 free(new_path);
1664 mfi.clean = 0;
1665 } else {
1666 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1668 return mfi.clean;
1672 /* Per entry merge function */
1673 static int process_entry(struct merge_options *o,
1674 const char *path, struct stage_data *entry)
1677 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1678 print_index_entry("\tpath: ", entry);
1680 int clean_merge = 1;
1681 int normalize = o->renormalize;
1682 unsigned o_mode = entry->stages[1].mode;
1683 unsigned a_mode = entry->stages[2].mode;
1684 unsigned b_mode = entry->stages[3].mode;
1685 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1686 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1687 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1689 entry->processed = 1;
1690 if (entry->rename_conflict_info) {
1691 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
1692 switch (conflict_info->rename_type) {
1693 case RENAME_NORMAL:
1694 case RENAME_ONE_FILE_TO_ONE:
1695 clean_merge = merge_content(o, path,
1696 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1697 conflict_info);
1698 break;
1699 case RENAME_DELETE:
1700 clean_merge = 0;
1701 conflict_rename_delete(o, conflict_info->pair1,
1702 conflict_info->branch1,
1703 conflict_info->branch2);
1704 break;
1705 case RENAME_ONE_FILE_TO_TWO:
1706 clean_merge = 0;
1707 conflict_rename_rename_1to2(o, conflict_info);
1708 break;
1709 case RENAME_TWO_FILES_TO_ONE:
1710 clean_merge = 0;
1711 conflict_rename_rename_2to1(o, conflict_info);
1712 break;
1713 default:
1714 entry->processed = 0;
1715 break;
1717 } else if (o_sha && (!a_sha || !b_sha)) {
1718 /* Case A: Deleted in one */
1719 if ((!a_sha && !b_sha) ||
1720 (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1721 (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1722 /* Deleted in both or deleted in one and
1723 * unchanged in the other */
1724 if (a_sha)
1725 output(o, 2, _("Removing %s"), path);
1726 /* do not touch working file if it did not exist */
1727 remove_file(o, 1, path, !a_sha);
1728 } else {
1729 /* Modify/delete; deleted side may have put a directory in the way */
1730 clean_merge = 0;
1731 handle_modify_delete(o, path, o_sha, o_mode,
1732 a_sha, a_mode, b_sha, b_mode);
1734 } else if ((!o_sha && a_sha && !b_sha) ||
1735 (!o_sha && !a_sha && b_sha)) {
1736 /* Case B: Added in one. */
1737 /* [nothing|directory] -> ([nothing|directory], file) */
1739 const char *add_branch;
1740 const char *other_branch;
1741 unsigned mode;
1742 const unsigned char *sha;
1743 const char *conf;
1745 if (a_sha) {
1746 add_branch = o->branch1;
1747 other_branch = o->branch2;
1748 mode = a_mode;
1749 sha = a_sha;
1750 conf = _("file/directory");
1751 } else {
1752 add_branch = o->branch2;
1753 other_branch = o->branch1;
1754 mode = b_mode;
1755 sha = b_sha;
1756 conf = _("directory/file");
1758 if (dir_in_way(path, !o->call_depth)) {
1759 char *new_path = unique_path(o, path, add_branch);
1760 clean_merge = 0;
1761 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
1762 "Adding %s as %s"),
1763 conf, path, other_branch, path, new_path);
1764 if (o->call_depth)
1765 remove_file_from_cache(path);
1766 update_file(o, 0, sha, mode, new_path);
1767 if (o->call_depth)
1768 remove_file_from_cache(path);
1769 free(new_path);
1770 } else {
1771 output(o, 2, _("Adding %s"), path);
1772 /* do not overwrite file if already present */
1773 update_file_flags(o, sha, mode, path, 1, !a_sha);
1775 } else if (a_sha && b_sha) {
1776 /* Case C: Added in both (check for same permissions) and */
1777 /* case D: Modified in both, but differently. */
1778 clean_merge = merge_content(o, path,
1779 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1780 NULL);
1781 } else if (!o_sha && !a_sha && !b_sha) {
1783 * this entry was deleted altogether. a_mode == 0 means
1784 * we had that path and want to actively remove it.
1786 remove_file(o, 1, path, !a_mode);
1787 } else
1788 die(_("Fatal merge failure, shouldn't happen."));
1790 return clean_merge;
1793 int merge_trees(struct merge_options *o,
1794 struct tree *head,
1795 struct tree *merge,
1796 struct tree *common,
1797 struct tree **result)
1799 int code, clean;
1801 if (o->subtree_shift) {
1802 merge = shift_tree_object(head, merge, o->subtree_shift);
1803 common = shift_tree_object(head, common, o->subtree_shift);
1806 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1807 output(o, 0, _("Already up-to-date!"));
1808 *result = head;
1809 return 1;
1812 code = git_merge_trees(o->call_depth, common, head, merge);
1814 if (code != 0) {
1815 if (show(o, 4) || o->call_depth)
1816 die(_("merging of trees %s and %s failed"),
1817 sha1_to_hex(head->object.sha1),
1818 sha1_to_hex(merge->object.sha1));
1819 else
1820 exit(128);
1823 if (unmerged_cache()) {
1824 struct string_list *entries, *re_head, *re_merge;
1825 int i;
1826 string_list_clear(&o->current_file_set, 1);
1827 string_list_clear(&o->current_directory_set, 1);
1828 get_files_dirs(o, head);
1829 get_files_dirs(o, merge);
1831 entries = get_unmerged();
1832 record_df_conflict_files(o, entries);
1833 re_head = get_renames(o, head, common, head, merge, entries);
1834 re_merge = get_renames(o, merge, common, head, merge, entries);
1835 clean = process_renames(o, re_head, re_merge);
1836 for (i = entries->nr-1; 0 <= i; i--) {
1837 const char *path = entries->items[i].string;
1838 struct stage_data *e = entries->items[i].util;
1839 if (!e->processed
1840 && !process_entry(o, path, e))
1841 clean = 0;
1843 for (i = 0; i < entries->nr; i++) {
1844 struct stage_data *e = entries->items[i].util;
1845 if (!e->processed)
1846 die(_("Unprocessed path??? %s"),
1847 entries->items[i].string);
1850 string_list_clear(re_merge, 0);
1851 string_list_clear(re_head, 0);
1852 string_list_clear(entries, 1);
1855 else
1856 clean = 1;
1858 if (o->call_depth)
1859 *result = write_tree_from_memory(o);
1861 return clean;
1864 static struct commit_list *reverse_commit_list(struct commit_list *list)
1866 struct commit_list *next = NULL, *current, *backup;
1867 for (current = list; current; current = backup) {
1868 backup = current->next;
1869 current->next = next;
1870 next = current;
1872 return next;
1876 * Merge the commits h1 and h2, return the resulting virtual
1877 * commit object and a flag indicating the cleanness of the merge.
1879 int merge_recursive(struct merge_options *o,
1880 struct commit *h1,
1881 struct commit *h2,
1882 struct commit_list *ca,
1883 struct commit **result)
1885 struct commit_list *iter;
1886 struct commit *merged_common_ancestors;
1887 struct tree *mrtree = mrtree;
1888 int clean;
1890 if (show(o, 4)) {
1891 output(o, 4, _("Merging:"));
1892 output_commit_title(o, h1);
1893 output_commit_title(o, h2);
1896 if (!ca) {
1897 ca = get_merge_bases(h1, h2, 1);
1898 ca = reverse_commit_list(ca);
1901 if (show(o, 5)) {
1902 unsigned cnt = commit_list_count(ca);
1904 output(o, 5, Q_("found %u common ancestor:",
1905 "found %u common ancestors:", cnt), cnt);
1906 for (iter = ca; iter; iter = iter->next)
1907 output_commit_title(o, iter->item);
1910 merged_common_ancestors = pop_commit(&ca);
1911 if (merged_common_ancestors == NULL) {
1912 /* if there is no common ancestor, use an empty tree */
1913 struct tree *tree;
1915 tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
1916 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1919 for (iter = ca; iter; iter = iter->next) {
1920 const char *saved_b1, *saved_b2;
1921 o->call_depth++;
1923 * When the merge fails, the result contains files
1924 * with conflict markers. The cleanness flag is
1925 * ignored, it was never actually used, as result of
1926 * merge_trees has always overwritten it: the committed
1927 * "conflicts" were already resolved.
1929 discard_cache();
1930 saved_b1 = o->branch1;
1931 saved_b2 = o->branch2;
1932 o->branch1 = "Temporary merge branch 1";
1933 o->branch2 = "Temporary merge branch 2";
1934 merge_recursive(o, merged_common_ancestors, iter->item,
1935 NULL, &merged_common_ancestors);
1936 o->branch1 = saved_b1;
1937 o->branch2 = saved_b2;
1938 o->call_depth--;
1940 if (!merged_common_ancestors)
1941 die(_("merge returned no commit"));
1944 discard_cache();
1945 if (!o->call_depth)
1946 read_cache();
1948 o->ancestor = "merged common ancestors";
1949 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1950 &mrtree);
1952 if (o->call_depth) {
1953 *result = make_virtual_commit(mrtree, "merged tree");
1954 commit_list_insert(h1, &(*result)->parents);
1955 commit_list_insert(h2, &(*result)->parents->next);
1957 flush_output(o);
1958 if (show(o, 2))
1959 diff_warn_rename_limit("merge.renamelimit",
1960 o->needed_rename_limit, 0);
1961 return clean;
1964 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1966 struct object *object;
1968 object = deref_tag(parse_object(sha1), name, strlen(name));
1969 if (!object)
1970 return NULL;
1971 if (object->type == OBJ_TREE)
1972 return make_virtual_commit((struct tree*)object, name);
1973 if (object->type != OBJ_COMMIT)
1974 return NULL;
1975 if (parse_commit((struct commit *)object))
1976 return NULL;
1977 return (struct commit *)object;
1980 int merge_recursive_generic(struct merge_options *o,
1981 const unsigned char *head,
1982 const unsigned char *merge,
1983 int num_base_list,
1984 const unsigned char **base_list,
1985 struct commit **result)
1987 int clean, index_fd;
1988 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1989 struct commit *head_commit = get_ref(head, o->branch1);
1990 struct commit *next_commit = get_ref(merge, o->branch2);
1991 struct commit_list *ca = NULL;
1993 if (base_list) {
1994 int i;
1995 for (i = 0; i < num_base_list; ++i) {
1996 struct commit *base;
1997 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1998 return error(_("Could not parse object '%s'"),
1999 sha1_to_hex(base_list[i]));
2000 commit_list_insert(base, &ca);
2004 index_fd = hold_locked_index(lock, 1);
2005 clean = merge_recursive(o, head_commit, next_commit, ca,
2006 result);
2007 if (active_cache_changed &&
2008 (write_cache(index_fd, active_cache, active_nr) ||
2009 commit_locked_index(lock)))
2010 return error(_("Unable to write index."));
2012 return clean ? 0 : 1;
2015 static int merge_recursive_config(const char *var, const char *value, void *cb)
2017 struct merge_options *o = cb;
2018 if (!strcmp(var, "merge.verbosity")) {
2019 o->verbosity = git_config_int(var, value);
2020 return 0;
2022 if (!strcmp(var, "diff.renamelimit")) {
2023 o->diff_rename_limit = git_config_int(var, value);
2024 return 0;
2026 if (!strcmp(var, "merge.renamelimit")) {
2027 o->merge_rename_limit = git_config_int(var, value);
2028 return 0;
2030 return git_xmerge_config(var, value, cb);
2033 void init_merge_options(struct merge_options *o)
2035 memset(o, 0, sizeof(struct merge_options));
2036 o->verbosity = 2;
2037 o->buffer_output = 1;
2038 o->diff_rename_limit = -1;
2039 o->merge_rename_limit = -1;
2040 o->renormalize = 0;
2041 git_config(merge_recursive_config, o);
2042 if (getenv("GIT_MERGE_VERBOSITY"))
2043 o->verbosity =
2044 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
2045 if (o->verbosity >= 5)
2046 o->buffer_output = 0;
2047 strbuf_init(&o->obuf, 0);
2048 memset(&o->current_file_set, 0, sizeof(struct string_list));
2049 o->current_file_set.strdup_strings = 1;
2050 memset(&o->current_directory_set, 0, sizeof(struct string_list));
2051 o->current_directory_set.strdup_strings = 1;
2052 memset(&o->df_conflict_file_set, 0, sizeof(struct string_list));
2053 o->df_conflict_file_set.strdup_strings = 1;
2056 int parse_merge_opt(struct merge_options *o, const char *s)
2058 if (!s || !*s)
2059 return -1;
2060 if (!strcmp(s, "ours"))
2061 o->recursive_variant = MERGE_RECURSIVE_OURS;
2062 else if (!strcmp(s, "theirs"))
2063 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
2064 else if (!strcmp(s, "subtree"))
2065 o->subtree_shift = "";
2066 else if (!prefixcmp(s, "subtree="))
2067 o->subtree_shift = s + strlen("subtree=");
2068 else if (!strcmp(s, "patience"))
2069 o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF);
2070 else if (!strcmp(s, "histogram"))
2071 o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF);
2072 else if (!strcmp(s, "diff-algorithm=")) {
2073 long value = parse_algorithm_value(s+15);
2074 if (value < 0)
2075 return -1;
2076 /* clear out previous settings */
2077 DIFF_XDL_CLR(o, NEED_MINIMAL);
2078 o->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
2079 o->xdl_opts |= value;
2081 else if (!strcmp(s, "ignore-space-change"))
2082 o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2083 else if (!strcmp(s, "ignore-all-space"))
2084 o->xdl_opts |= XDF_IGNORE_WHITESPACE;
2085 else if (!strcmp(s, "ignore-space-at-eol"))
2086 o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2087 else if (!strcmp(s, "renormalize"))
2088 o->renormalize = 1;
2089 else if (!strcmp(s, "no-renormalize"))
2090 o->renormalize = 0;
2091 else if (!prefixcmp(s, "rename-threshold=")) {
2092 const char *score = s + strlen("rename-threshold=");
2093 if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
2094 return -1;
2096 else
2097 return -1;
2098 return 0;