stash: invoke rerere in case of conflict
[git/mingw.git] / merge-recursive.c
blobd83cd6c662847fb51641d7b8bf16739e588f67a2
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 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 active_cache, active_nr, 0, 0, 0) < 0)
268 die("error building trees");
270 result = lookup_tree(active_cache_tree->sha1);
272 return result;
275 static int save_files_dirs(const unsigned char *sha1,
276 const char *base, int baselen, const char *path,
277 unsigned int mode, int stage, void *context)
279 int len = strlen(path);
280 char *newpath = xmalloc(baselen + len + 1);
281 struct merge_options *o = context;
283 memcpy(newpath, base, baselen);
284 memcpy(newpath + baselen, path, len);
285 newpath[baselen + len] = '\0';
287 if (S_ISDIR(mode))
288 string_list_insert(&o->current_directory_set, newpath);
289 else
290 string_list_insert(&o->current_file_set, newpath);
291 free(newpath);
293 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
296 static int get_files_dirs(struct merge_options *o, struct tree *tree)
298 int n;
299 struct pathspec match_all;
300 init_pathspec(&match_all, NULL);
301 if (read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o))
302 return 0;
303 n = o->current_file_set.nr + o->current_directory_set.nr;
304 return n;
308 * Returns an index_entry instance which doesn't have to correspond to
309 * a real cache entry in Git's index.
311 static struct stage_data *insert_stage_data(const char *path,
312 struct tree *o, struct tree *a, struct tree *b,
313 struct string_list *entries)
315 struct string_list_item *item;
316 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
317 get_tree_entry(o->object.sha1, path,
318 e->stages[1].sha, &e->stages[1].mode);
319 get_tree_entry(a->object.sha1, path,
320 e->stages[2].sha, &e->stages[2].mode);
321 get_tree_entry(b->object.sha1, path,
322 e->stages[3].sha, &e->stages[3].mode);
323 item = string_list_insert(entries, path);
324 item->util = e;
325 return e;
329 * Create a dictionary mapping file names to stage_data objects. The
330 * dictionary contains one entry for every path with a non-zero stage entry.
332 static struct string_list *get_unmerged(void)
334 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
335 int i;
337 unmerged->strdup_strings = 1;
339 for (i = 0; i < active_nr; i++) {
340 struct string_list_item *item;
341 struct stage_data *e;
342 struct cache_entry *ce = active_cache[i];
343 if (!ce_stage(ce))
344 continue;
346 item = string_list_lookup(unmerged, ce->name);
347 if (!item) {
348 item = string_list_insert(unmerged, ce->name);
349 item->util = xcalloc(1, sizeof(struct stage_data));
351 e = item->util;
352 e->stages[ce_stage(ce)].mode = ce->ce_mode;
353 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
356 return unmerged;
359 static int string_list_df_name_compare(const void *a, const void *b)
361 const struct string_list_item *one = a;
362 const struct string_list_item *two = b;
363 int onelen = strlen(one->string);
364 int twolen = strlen(two->string);
366 * Here we only care that entries for D/F conflicts are
367 * adjacent, in particular with the file of the D/F conflict
368 * appearing before files below the corresponding directory.
369 * The order of the rest of the list is irrelevant for us.
371 * To achieve this, we sort with df_name_compare and provide
372 * the mode S_IFDIR so that D/F conflicts will sort correctly.
373 * We use the mode S_IFDIR for everything else for simplicity,
374 * since in other cases any changes in their order due to
375 * sorting cause no problems for us.
377 int cmp = df_name_compare(one->string, onelen, S_IFDIR,
378 two->string, twolen, S_IFDIR);
380 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
381 * that 'foo' comes before 'foo/bar'.
383 if (cmp)
384 return cmp;
385 return onelen - twolen;
388 static void record_df_conflict_files(struct merge_options *o,
389 struct string_list *entries)
391 /* If there is a D/F conflict and the file for such a conflict
392 * currently exist in the working tree, we want to allow it to be
393 * removed to make room for the corresponding directory if needed.
394 * The files underneath the directories of such D/F conflicts will
395 * be processed before the corresponding file involved in the D/F
396 * conflict. If the D/F directory ends up being removed by the
397 * merge, then we won't have to touch the D/F file. If the D/F
398 * directory needs to be written to the working copy, then the D/F
399 * file will simply be removed (in make_room_for_path()) to make
400 * room for the necessary paths. Note that if both the directory
401 * and the file need to be present, then the D/F file will be
402 * reinstated with a new unique name at the time it is processed.
404 struct string_list df_sorted_entries;
405 const char *last_file = NULL;
406 int last_len = 0;
407 int i;
410 * If we're merging merge-bases, we don't want to bother with
411 * any working directory changes.
413 if (o->call_depth)
414 return;
416 /* Ensure D/F conflicts are adjacent in the entries list. */
417 memset(&df_sorted_entries, 0, sizeof(struct string_list));
418 for (i = 0; i < entries->nr; i++) {
419 struct string_list_item *next = &entries->items[i];
420 string_list_append(&df_sorted_entries, next->string)->util =
421 next->util;
423 qsort(df_sorted_entries.items, entries->nr, sizeof(*entries->items),
424 string_list_df_name_compare);
426 string_list_clear(&o->df_conflict_file_set, 1);
427 for (i = 0; i < df_sorted_entries.nr; i++) {
428 const char *path = df_sorted_entries.items[i].string;
429 int len = strlen(path);
430 struct stage_data *e = df_sorted_entries.items[i].util;
433 * Check if last_file & path correspond to a D/F conflict;
434 * i.e. whether path is last_file+'/'+<something>.
435 * If so, record that it's okay to remove last_file to make
436 * room for path and friends if needed.
438 if (last_file &&
439 len > last_len &&
440 memcmp(path, last_file, last_len) == 0 &&
441 path[last_len] == '/') {
442 string_list_insert(&o->df_conflict_file_set, last_file);
446 * Determine whether path could exist as a file in the
447 * working directory as a possible D/F conflict. This
448 * will only occur when it exists in stage 2 as a
449 * file.
451 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
452 last_file = path;
453 last_len = len;
454 } else {
455 last_file = NULL;
458 string_list_clear(&df_sorted_entries, 0);
461 struct rename {
462 struct diff_filepair *pair;
463 struct stage_data *src_entry;
464 struct stage_data *dst_entry;
465 unsigned processed:1;
469 * Get information of all renames which occurred between 'o_tree' and
470 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
471 * 'b_tree') to be able to associate the correct cache entries with
472 * the rename information. 'tree' is always equal to either a_tree or b_tree.
474 static struct string_list *get_renames(struct merge_options *o,
475 struct tree *tree,
476 struct tree *o_tree,
477 struct tree *a_tree,
478 struct tree *b_tree,
479 struct string_list *entries)
481 int i;
482 struct string_list *renames;
483 struct diff_options opts;
485 renames = xcalloc(1, sizeof(struct string_list));
486 diff_setup(&opts);
487 DIFF_OPT_SET(&opts, RECURSIVE);
488 opts.detect_rename = DIFF_DETECT_RENAME;
489 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
490 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
491 1000;
492 opts.rename_score = o->rename_score;
493 opts.show_rename_progress = o->show_rename_progress;
494 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
495 if (diff_setup_done(&opts) < 0)
496 die("diff setup failed");
497 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
498 diffcore_std(&opts);
499 if (opts.needed_rename_limit > o->needed_rename_limit)
500 o->needed_rename_limit = opts.needed_rename_limit;
501 for (i = 0; i < diff_queued_diff.nr; ++i) {
502 struct string_list_item *item;
503 struct rename *re;
504 struct diff_filepair *pair = diff_queued_diff.queue[i];
505 if (pair->status != 'R') {
506 diff_free_filepair(pair);
507 continue;
509 re = xmalloc(sizeof(*re));
510 re->processed = 0;
511 re->pair = pair;
512 item = string_list_lookup(entries, re->pair->one->path);
513 if (!item)
514 re->src_entry = insert_stage_data(re->pair->one->path,
515 o_tree, a_tree, b_tree, entries);
516 else
517 re->src_entry = item->util;
519 item = string_list_lookup(entries, re->pair->two->path);
520 if (!item)
521 re->dst_entry = insert_stage_data(re->pair->two->path,
522 o_tree, a_tree, b_tree, entries);
523 else
524 re->dst_entry = item->util;
525 item = string_list_insert(renames, pair->one->path);
526 item->util = re;
528 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
529 diff_queued_diff.nr = 0;
530 diff_flush(&opts);
531 return renames;
534 static int update_stages(const char *path, const struct diff_filespec *o,
535 const struct diff_filespec *a,
536 const struct diff_filespec *b)
540 * NOTE: It is usually a bad idea to call update_stages on a path
541 * before calling update_file on that same path, since it can
542 * sometimes lead to spurious "refusing to lose untracked file..."
543 * messages from update_file (via make_room_for path via
544 * would_lose_untracked). Instead, reverse the order of the calls
545 * (executing update_file first and then update_stages).
547 int clear = 1;
548 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
549 if (clear)
550 if (remove_file_from_cache(path))
551 return -1;
552 if (o)
553 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
554 return -1;
555 if (a)
556 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
557 return -1;
558 if (b)
559 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
560 return -1;
561 return 0;
564 static void update_entry(struct stage_data *entry,
565 struct diff_filespec *o,
566 struct diff_filespec *a,
567 struct diff_filespec *b)
569 entry->processed = 0;
570 entry->stages[1].mode = o->mode;
571 entry->stages[2].mode = a->mode;
572 entry->stages[3].mode = b->mode;
573 hashcpy(entry->stages[1].sha, o->sha1);
574 hashcpy(entry->stages[2].sha, a->sha1);
575 hashcpy(entry->stages[3].sha, b->sha1);
578 static int remove_file(struct merge_options *o, int clean,
579 const char *path, int no_wd)
581 int update_cache = o->call_depth || clean;
582 int update_working_directory = !o->call_depth && !no_wd;
584 if (update_cache) {
585 if (remove_file_from_cache(path))
586 return -1;
588 if (update_working_directory) {
589 if (remove_path(path))
590 return -1;
592 return 0;
595 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
597 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
598 int suffix = 0;
599 struct stat st;
600 char *p = newpath + strlen(path);
601 strcpy(newpath, path);
602 *(p++) = '~';
603 strcpy(p, branch);
604 for (; *p; ++p)
605 if ('/' == *p)
606 *p = '_';
607 while (string_list_has_string(&o->current_file_set, newpath) ||
608 string_list_has_string(&o->current_directory_set, newpath) ||
609 lstat(newpath, &st) == 0)
610 sprintf(p, "_%d", suffix++);
612 string_list_insert(&o->current_file_set, newpath);
613 return newpath;
616 static void flush_buffer(int fd, const char *buf, unsigned long size)
618 while (size > 0) {
619 long ret = write_in_full(fd, buf, size);
620 if (ret < 0) {
621 /* Ignore epipe */
622 if (errno == EPIPE)
623 break;
624 die_errno("merge-recursive");
625 } else if (!ret) {
626 die("merge-recursive: disk full?");
628 size -= ret;
629 buf += ret;
633 static int dir_in_way(const char *path, int check_working_copy)
635 int pos, pathlen = strlen(path);
636 char *dirpath = xmalloc(pathlen + 2);
637 struct stat st;
639 strcpy(dirpath, path);
640 dirpath[pathlen] = '/';
641 dirpath[pathlen+1] = '\0';
643 pos = cache_name_pos(dirpath, pathlen+1);
645 if (pos < 0)
646 pos = -1 - pos;
647 if (pos < active_nr &&
648 !strncmp(dirpath, active_cache[pos]->name, pathlen+1)) {
649 free(dirpath);
650 return 1;
653 free(dirpath);
654 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode);
657 static int was_tracked(const char *path)
659 int pos = cache_name_pos(path, strlen(path));
661 if (pos < 0)
662 pos = -1 - pos;
663 while (pos < active_nr &&
664 !strcmp(path, active_cache[pos]->name)) {
666 * If stage #0, it is definitely tracked.
667 * If it has stage #2 then it was tracked
668 * before this merge started. All other
669 * cases the path was not tracked.
671 switch (ce_stage(active_cache[pos])) {
672 case 0:
673 case 2:
674 return 1;
676 pos++;
678 return 0;
681 static int would_lose_untracked(const char *path)
683 return !was_tracked(path) && file_exists(path);
686 static int make_room_for_path(struct merge_options *o, const char *path)
688 int status, i;
689 const char *msg = "failed to create path '%s'%s";
691 /* Unlink any D/F conflict files that are in the way */
692 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
693 const char *df_path = o->df_conflict_file_set.items[i].string;
694 size_t pathlen = strlen(path);
695 size_t df_pathlen = strlen(df_path);
696 if (df_pathlen < pathlen &&
697 path[df_pathlen] == '/' &&
698 strncmp(path, df_path, df_pathlen) == 0) {
699 output(o, 3,
700 "Removing %s to make room for subdirectory\n",
701 df_path);
702 unlink(df_path);
703 unsorted_string_list_delete_item(&o->df_conflict_file_set,
704 i, 0);
705 break;
709 /* Make sure leading directories are created */
710 status = safe_create_leading_directories_const(path);
711 if (status) {
712 if (status == -3) {
713 /* something else exists */
714 error(msg, path, ": perhaps a D/F conflict?");
715 return -1;
717 die(msg, path, "");
721 * Do not unlink a file in the work tree if we are not
722 * tracking it.
724 if (would_lose_untracked(path))
725 return error("refusing to lose untracked file at '%s'",
726 path);
728 /* Successful unlink is good.. */
729 if (!unlink(path))
730 return 0;
731 /* .. and so is no existing file */
732 if (errno == ENOENT)
733 return 0;
734 /* .. but not some other error (who really cares what?) */
735 return error(msg, path, ": perhaps a D/F conflict?");
738 static void update_file_flags(struct merge_options *o,
739 const unsigned char *sha,
740 unsigned mode,
741 const char *path,
742 int update_cache,
743 int update_wd)
745 if (o->call_depth)
746 update_wd = 0;
748 if (update_wd) {
749 enum object_type type;
750 void *buf;
751 unsigned long size;
753 if (S_ISGITLINK(mode)) {
755 * We may later decide to recursively descend into
756 * the submodule directory and update its index
757 * and/or work tree, but we do not do that now.
759 update_wd = 0;
760 goto update_index;
763 buf = read_sha1_file(sha, &type, &size);
764 if (!buf)
765 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
766 if (type != OBJ_BLOB)
767 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
768 if (S_ISREG(mode)) {
769 struct strbuf strbuf = STRBUF_INIT;
770 if (convert_to_working_tree(path, buf, size, &strbuf)) {
771 free(buf);
772 size = strbuf.len;
773 buf = strbuf_detach(&strbuf, NULL);
777 if (make_room_for_path(o, path) < 0) {
778 update_wd = 0;
779 free(buf);
780 goto update_index;
782 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
783 int fd;
784 if (mode & 0100)
785 mode = 0777;
786 else
787 mode = 0666;
788 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
789 if (fd < 0)
790 die_errno("failed to open '%s'", path);
791 flush_buffer(fd, buf, size);
792 close(fd);
793 } else if (S_ISLNK(mode)) {
794 char *lnk = xmemdupz(buf, size);
795 safe_create_leading_directories_const(path);
796 unlink(path);
797 if (symlink(lnk, path))
798 die_errno("failed to symlink '%s'", path);
799 free(lnk);
800 } else
801 die("do not know what to do with %06o %s '%s'",
802 mode, sha1_to_hex(sha), path);
803 free(buf);
805 update_index:
806 if (update_cache)
807 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
810 static void update_file(struct merge_options *o,
811 int clean,
812 const unsigned char *sha,
813 unsigned mode,
814 const char *path)
816 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
819 /* Low level file merging, update and removal */
821 struct merge_file_info {
822 unsigned char sha[20];
823 unsigned mode;
824 unsigned clean:1,
825 merge:1;
828 static int merge_3way(struct merge_options *o,
829 mmbuffer_t *result_buf,
830 const struct diff_filespec *one,
831 const struct diff_filespec *a,
832 const struct diff_filespec *b,
833 const char *branch1,
834 const char *branch2)
836 mmfile_t orig, src1, src2;
837 struct ll_merge_options ll_opts = {0};
838 char *base_name, *name1, *name2;
839 int merge_status;
841 ll_opts.renormalize = o->renormalize;
842 ll_opts.xdl_opts = o->xdl_opts;
844 if (o->call_depth) {
845 ll_opts.virtual_ancestor = 1;
846 ll_opts.variant = 0;
847 } else {
848 switch (o->recursive_variant) {
849 case MERGE_RECURSIVE_OURS:
850 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
851 break;
852 case MERGE_RECURSIVE_THEIRS:
853 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
854 break;
855 default:
856 ll_opts.variant = 0;
857 break;
861 if (strcmp(a->path, b->path) ||
862 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
863 base_name = o->ancestor == NULL ? NULL :
864 xstrdup(mkpath("%s:%s", o->ancestor, one->path));
865 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
866 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
867 } else {
868 base_name = o->ancestor == NULL ? NULL :
869 xstrdup(mkpath("%s", o->ancestor));
870 name1 = xstrdup(mkpath("%s", branch1));
871 name2 = xstrdup(mkpath("%s", branch2));
874 read_mmblob(&orig, one->sha1);
875 read_mmblob(&src1, a->sha1);
876 read_mmblob(&src2, b->sha1);
878 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
879 &src1, name1, &src2, name2, &ll_opts);
881 free(name1);
882 free(name2);
883 free(orig.ptr);
884 free(src1.ptr);
885 free(src2.ptr);
886 return merge_status;
889 static struct merge_file_info merge_file_1(struct merge_options *o,
890 const struct diff_filespec *one,
891 const struct diff_filespec *a,
892 const struct diff_filespec *b,
893 const char *branch1,
894 const char *branch2)
896 struct merge_file_info result;
897 result.merge = 0;
898 result.clean = 1;
900 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
901 result.clean = 0;
902 if (S_ISREG(a->mode)) {
903 result.mode = a->mode;
904 hashcpy(result.sha, a->sha1);
905 } else {
906 result.mode = b->mode;
907 hashcpy(result.sha, b->sha1);
909 } else {
910 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
911 result.merge = 1;
914 * Merge modes
916 if (a->mode == b->mode || a->mode == one->mode)
917 result.mode = b->mode;
918 else {
919 result.mode = a->mode;
920 if (b->mode != one->mode) {
921 result.clean = 0;
922 result.merge = 1;
926 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
927 hashcpy(result.sha, b->sha1);
928 else if (sha_eq(b->sha1, one->sha1))
929 hashcpy(result.sha, a->sha1);
930 else if (S_ISREG(a->mode)) {
931 mmbuffer_t result_buf;
932 int merge_status;
934 merge_status = merge_3way(o, &result_buf, one, a, b,
935 branch1, branch2);
937 if ((merge_status < 0) || !result_buf.ptr)
938 die("Failed to execute internal merge");
940 if (write_sha1_file(result_buf.ptr, result_buf.size,
941 blob_type, result.sha))
942 die("Unable to add %s to database",
943 a->path);
945 free(result_buf.ptr);
946 result.clean = (merge_status == 0);
947 } else if (S_ISGITLINK(a->mode)) {
948 result.clean = merge_submodule(result.sha,
949 one->path, one->sha1,
950 a->sha1, b->sha1,
951 !o->call_depth);
952 } else if (S_ISLNK(a->mode)) {
953 hashcpy(result.sha, a->sha1);
955 if (!sha_eq(a->sha1, b->sha1))
956 result.clean = 0;
957 } else {
958 die("unsupported object type in the tree");
962 return result;
965 static struct merge_file_info
966 merge_file_special_markers(struct merge_options *o,
967 const struct diff_filespec *one,
968 const struct diff_filespec *a,
969 const struct diff_filespec *b,
970 const char *branch1,
971 const char *filename1,
972 const char *branch2,
973 const char *filename2)
975 char *side1 = NULL;
976 char *side2 = NULL;
977 struct merge_file_info mfi;
979 if (filename1) {
980 side1 = xmalloc(strlen(branch1) + strlen(filename1) + 2);
981 sprintf(side1, "%s:%s", branch1, filename1);
983 if (filename2) {
984 side2 = xmalloc(strlen(branch2) + strlen(filename2) + 2);
985 sprintf(side2, "%s:%s", branch2, filename2);
988 mfi = merge_file_1(o, one, a, b,
989 side1 ? side1 : branch1, side2 ? side2 : branch2);
990 free(side1);
991 free(side2);
992 return mfi;
995 static struct merge_file_info merge_file(struct merge_options *o,
996 const char *path,
997 const unsigned char *o_sha, int o_mode,
998 const unsigned char *a_sha, int a_mode,
999 const unsigned char *b_sha, int b_mode,
1000 const char *branch1,
1001 const char *branch2)
1003 struct diff_filespec one, a, b;
1005 one.path = a.path = b.path = (char *)path;
1006 hashcpy(one.sha1, o_sha);
1007 one.mode = o_mode;
1008 hashcpy(a.sha1, a_sha);
1009 a.mode = a_mode;
1010 hashcpy(b.sha1, b_sha);
1011 b.mode = b_mode;
1012 return merge_file_1(o, &one, &a, &b, branch1, branch2);
1015 static void handle_change_delete(struct merge_options *o,
1016 const char *path,
1017 const unsigned char *o_sha, int o_mode,
1018 const unsigned char *a_sha, int a_mode,
1019 const unsigned char *b_sha, int b_mode,
1020 const char *change, const char *change_past)
1022 char *renamed = NULL;
1023 if (dir_in_way(path, !o->call_depth)) {
1024 renamed = unique_path(o, path, a_sha ? o->branch1 : o->branch2);
1027 if (o->call_depth) {
1029 * We cannot arbitrarily accept either a_sha or b_sha as
1030 * correct; since there is no true "middle point" between
1031 * them, simply reuse the base version for virtual merge base.
1033 remove_file_from_cache(path);
1034 update_file(o, 0, o_sha, o_mode, renamed ? renamed : path);
1035 } else if (!a_sha) {
1036 output(o, 1, "CONFLICT (%s/delete): %s deleted in %s "
1037 "and %s in %s. Version %s of %s left in tree%s%s.",
1038 change, path, o->branch1,
1039 change_past, o->branch2, o->branch2, path,
1040 NULL == renamed ? "" : " at ",
1041 NULL == renamed ? "" : renamed);
1042 update_file(o, 0, b_sha, b_mode, renamed ? renamed : path);
1043 } else {
1044 output(o, 1, "CONFLICT (%s/delete): %s deleted in %s "
1045 "and %s in %s. Version %s of %s left in tree%s%s.",
1046 change, path, o->branch2,
1047 change_past, o->branch1, o->branch1, path,
1048 NULL == renamed ? "" : " at ",
1049 NULL == renamed ? "" : renamed);
1050 if (renamed)
1051 update_file(o, 0, a_sha, a_mode, renamed);
1053 * No need to call update_file() on path when !renamed, since
1054 * that would needlessly touch path. We could call
1055 * update_file_flags() with update_cache=0 and update_wd=0,
1056 * but that's a no-op.
1059 free(renamed);
1062 static void conflict_rename_delete(struct merge_options *o,
1063 struct diff_filepair *pair,
1064 const char *rename_branch,
1065 const char *other_branch)
1067 const struct diff_filespec *orig = pair->one;
1068 const struct diff_filespec *dest = pair->two;
1069 const unsigned char *a_sha = NULL;
1070 const unsigned char *b_sha = NULL;
1071 int a_mode = 0;
1072 int b_mode = 0;
1074 if (rename_branch == o->branch1) {
1075 a_sha = dest->sha1;
1076 a_mode = dest->mode;
1077 } else {
1078 b_sha = dest->sha1;
1079 b_mode = dest->mode;
1082 handle_change_delete(o,
1083 o->call_depth ? orig->path : dest->path,
1084 orig->sha1, orig->mode,
1085 a_sha, a_mode,
1086 b_sha, b_mode,
1087 "rename", "renamed");
1089 if (o->call_depth) {
1090 remove_file_from_cache(dest->path);
1091 } else {
1092 update_stages(dest->path, NULL,
1093 rename_branch == o->branch1 ? dest : NULL,
1094 rename_branch == o->branch1 ? NULL : dest);
1099 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1100 struct stage_data *entry,
1101 int stage)
1103 unsigned char *sha = entry->stages[stage].sha;
1104 unsigned mode = entry->stages[stage].mode;
1105 if (mode == 0 || is_null_sha1(sha))
1106 return NULL;
1107 hashcpy(target->sha1, sha);
1108 target->mode = mode;
1109 return target;
1112 static void handle_file(struct merge_options *o,
1113 struct diff_filespec *rename,
1114 int stage,
1115 struct rename_conflict_info *ci)
1117 char *dst_name = rename->path;
1118 struct stage_data *dst_entry;
1119 const char *cur_branch, *other_branch;
1120 struct diff_filespec other;
1121 struct diff_filespec *add;
1123 if (stage == 2) {
1124 dst_entry = ci->dst_entry1;
1125 cur_branch = ci->branch1;
1126 other_branch = ci->branch2;
1127 } else {
1128 dst_entry = ci->dst_entry2;
1129 cur_branch = ci->branch2;
1130 other_branch = ci->branch1;
1133 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1134 if (add) {
1135 char *add_name = unique_path(o, rename->path, other_branch);
1136 update_file(o, 0, add->sha1, add->mode, add_name);
1138 remove_file(o, 0, rename->path, 0);
1139 dst_name = unique_path(o, rename->path, cur_branch);
1140 } else {
1141 if (dir_in_way(rename->path, !o->call_depth)) {
1142 dst_name = unique_path(o, rename->path, cur_branch);
1143 output(o, 1, "%s is a directory in %s adding as %s instead",
1144 rename->path, other_branch, dst_name);
1147 update_file(o, 0, rename->sha1, rename->mode, dst_name);
1148 if (stage == 2)
1149 update_stages(rename->path, NULL, rename, add);
1150 else
1151 update_stages(rename->path, NULL, add, rename);
1153 if (dst_name != rename->path)
1154 free(dst_name);
1157 static void conflict_rename_rename_1to2(struct merge_options *o,
1158 struct rename_conflict_info *ci)
1160 /* One file was renamed in both branches, but to different names. */
1161 struct diff_filespec *one = ci->pair1->one;
1162 struct diff_filespec *a = ci->pair1->two;
1163 struct diff_filespec *b = ci->pair2->two;
1165 output(o, 1, "CONFLICT (rename/rename): "
1166 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1167 "rename \"%s\"->\"%s\" in \"%s\"%s",
1168 one->path, a->path, ci->branch1,
1169 one->path, b->path, ci->branch2,
1170 o->call_depth ? " (left unresolved)" : "");
1171 if (o->call_depth) {
1172 struct merge_file_info mfi;
1173 struct diff_filespec other;
1174 struct diff_filespec *add;
1175 mfi = merge_file(o, one->path,
1176 one->sha1, one->mode,
1177 a->sha1, a->mode,
1178 b->sha1, b->mode,
1179 ci->branch1, ci->branch2);
1181 * FIXME: For rename/add-source conflicts (if we could detect
1182 * such), this is wrong. We should instead find a unique
1183 * pathname and then either rename the add-source file to that
1184 * unique path, or use that unique path instead of src here.
1186 update_file(o, 0, mfi.sha, mfi.mode, one->path);
1189 * Above, we put the merged content at the merge-base's
1190 * path. Now we usually need to delete both a->path and
1191 * b->path. However, the rename on each side of the merge
1192 * could also be involved in a rename/add conflict. In
1193 * such cases, we should keep the added file around,
1194 * resolving the conflict at that path in its favor.
1196 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1197 if (add)
1198 update_file(o, 0, add->sha1, add->mode, a->path);
1199 else
1200 remove_file_from_cache(a->path);
1201 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1202 if (add)
1203 update_file(o, 0, add->sha1, add->mode, b->path);
1204 else
1205 remove_file_from_cache(b->path);
1206 } else {
1207 handle_file(o, a, 2, ci);
1208 handle_file(o, b, 3, ci);
1212 static void conflict_rename_rename_2to1(struct merge_options *o,
1213 struct rename_conflict_info *ci)
1215 /* Two files, a & b, were renamed to the same thing, c. */
1216 struct diff_filespec *a = ci->pair1->one;
1217 struct diff_filespec *b = ci->pair2->one;
1218 struct diff_filespec *c1 = ci->pair1->two;
1219 struct diff_filespec *c2 = ci->pair2->two;
1220 char *path = c1->path; /* == c2->path */
1221 struct merge_file_info mfi_c1;
1222 struct merge_file_info mfi_c2;
1224 output(o, 1, "CONFLICT (rename/rename): "
1225 "Rename %s->%s in %s. "
1226 "Rename %s->%s in %s",
1227 a->path, c1->path, ci->branch1,
1228 b->path, c2->path, ci->branch2);
1230 remove_file(o, 1, a->path, would_lose_untracked(a->path));
1231 remove_file(o, 1, b->path, would_lose_untracked(b->path));
1233 mfi_c1 = merge_file_special_markers(o, a, c1, &ci->ren1_other,
1234 o->branch1, c1->path,
1235 o->branch2, ci->ren1_other.path);
1236 mfi_c2 = merge_file_special_markers(o, b, &ci->ren2_other, c2,
1237 o->branch1, ci->ren2_other.path,
1238 o->branch2, c2->path);
1240 if (o->call_depth) {
1242 * If mfi_c1.clean && mfi_c2.clean, then it might make
1243 * sense to do a two-way merge of those results. But, I
1244 * think in all cases, it makes sense to have the virtual
1245 * merge base just undo the renames; they can be detected
1246 * again later for the non-recursive merge.
1248 remove_file(o, 0, path, 0);
1249 update_file(o, 0, mfi_c1.sha, mfi_c1.mode, a->path);
1250 update_file(o, 0, mfi_c2.sha, mfi_c2.mode, b->path);
1251 } else {
1252 char *new_path1 = unique_path(o, path, ci->branch1);
1253 char *new_path2 = unique_path(o, path, ci->branch2);
1254 output(o, 1, "Renaming %s to %s and %s to %s instead",
1255 a->path, new_path1, b->path, new_path2);
1256 remove_file(o, 0, path, 0);
1257 update_file(o, 0, mfi_c1.sha, mfi_c1.mode, new_path1);
1258 update_file(o, 0, mfi_c2.sha, mfi_c2.mode, new_path2);
1259 free(new_path2);
1260 free(new_path1);
1264 static int process_renames(struct merge_options *o,
1265 struct string_list *a_renames,
1266 struct string_list *b_renames)
1268 int clean_merge = 1, i, j;
1269 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
1270 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
1271 const struct rename *sre;
1273 for (i = 0; i < a_renames->nr; i++) {
1274 sre = a_renames->items[i].util;
1275 string_list_insert(&a_by_dst, sre->pair->two->path)->util
1276 = (void *)sre;
1278 for (i = 0; i < b_renames->nr; i++) {
1279 sre = b_renames->items[i].util;
1280 string_list_insert(&b_by_dst, sre->pair->two->path)->util
1281 = (void *)sre;
1284 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1285 struct string_list *renames1, *renames2Dst;
1286 struct rename *ren1 = NULL, *ren2 = NULL;
1287 const char *branch1, *branch2;
1288 const char *ren1_src, *ren1_dst;
1289 struct string_list_item *lookup;
1291 if (i >= a_renames->nr) {
1292 ren2 = b_renames->items[j++].util;
1293 } else if (j >= b_renames->nr) {
1294 ren1 = a_renames->items[i++].util;
1295 } else {
1296 int compare = strcmp(a_renames->items[i].string,
1297 b_renames->items[j].string);
1298 if (compare <= 0)
1299 ren1 = a_renames->items[i++].util;
1300 if (compare >= 0)
1301 ren2 = b_renames->items[j++].util;
1304 /* TODO: refactor, so that 1/2 are not needed */
1305 if (ren1) {
1306 renames1 = a_renames;
1307 renames2Dst = &b_by_dst;
1308 branch1 = o->branch1;
1309 branch2 = o->branch2;
1310 } else {
1311 struct rename *tmp;
1312 renames1 = b_renames;
1313 renames2Dst = &a_by_dst;
1314 branch1 = o->branch2;
1315 branch2 = o->branch1;
1316 tmp = ren2;
1317 ren2 = ren1;
1318 ren1 = tmp;
1321 if (ren1->processed)
1322 continue;
1323 ren1->processed = 1;
1324 ren1->dst_entry->processed = 1;
1325 /* BUG: We should only mark src_entry as processed if we
1326 * are not dealing with a rename + add-source case.
1328 ren1->src_entry->processed = 1;
1330 ren1_src = ren1->pair->one->path;
1331 ren1_dst = ren1->pair->two->path;
1333 if (ren2) {
1334 /* One file renamed on both sides */
1335 const char *ren2_src = ren2->pair->one->path;
1336 const char *ren2_dst = ren2->pair->two->path;
1337 enum rename_type rename_type;
1338 if (strcmp(ren1_src, ren2_src) != 0)
1339 die("ren1_src != ren2_src");
1340 ren2->dst_entry->processed = 1;
1341 ren2->processed = 1;
1342 if (strcmp(ren1_dst, ren2_dst) != 0) {
1343 rename_type = RENAME_ONE_FILE_TO_TWO;
1344 clean_merge = 0;
1345 } else {
1346 rename_type = RENAME_ONE_FILE_TO_ONE;
1347 /* BUG: We should only remove ren1_src in
1348 * the base stage (think of rename +
1349 * add-source cases).
1351 remove_file(o, 1, ren1_src, 1);
1352 update_entry(ren1->dst_entry,
1353 ren1->pair->one,
1354 ren1->pair->two,
1355 ren2->pair->two);
1357 setup_rename_conflict_info(rename_type,
1358 ren1->pair,
1359 ren2->pair,
1360 branch1,
1361 branch2,
1362 ren1->dst_entry,
1363 ren2->dst_entry,
1365 NULL,
1366 NULL);
1367 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
1368 /* Two different files renamed to the same thing */
1369 char *ren2_dst;
1370 ren2 = lookup->util;
1371 ren2_dst = ren2->pair->two->path;
1372 if (strcmp(ren1_dst, ren2_dst) != 0)
1373 die("ren1_dst != ren2_dst");
1375 clean_merge = 0;
1376 ren2->processed = 1;
1378 * BUG: We should only mark src_entry as processed
1379 * if we are not dealing with a rename + add-source
1380 * case.
1382 ren2->src_entry->processed = 1;
1384 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
1385 ren1->pair,
1386 ren2->pair,
1387 branch1,
1388 branch2,
1389 ren1->dst_entry,
1390 ren2->dst_entry,
1392 ren1->src_entry,
1393 ren2->src_entry);
1395 } else {
1396 /* Renamed in 1, maybe changed in 2 */
1397 /* we only use sha1 and mode of these */
1398 struct diff_filespec src_other, dst_other;
1399 int try_merge;
1402 * unpack_trees loads entries from common-commit
1403 * into stage 1, from head-commit into stage 2, and
1404 * from merge-commit into stage 3. We keep track
1405 * of which side corresponds to the rename.
1407 int renamed_stage = a_renames == renames1 ? 2 : 3;
1408 int other_stage = a_renames == renames1 ? 3 : 2;
1410 /* BUG: We should only remove ren1_src in the base
1411 * stage and in other_stage (think of rename +
1412 * add-source case).
1414 remove_file(o, 1, ren1_src,
1415 renamed_stage == 2 || !was_tracked(ren1_src));
1417 hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
1418 src_other.mode = ren1->src_entry->stages[other_stage].mode;
1419 hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
1420 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1421 try_merge = 0;
1423 if (sha_eq(src_other.sha1, null_sha1)) {
1424 setup_rename_conflict_info(RENAME_DELETE,
1425 ren1->pair,
1426 NULL,
1427 branch1,
1428 branch2,
1429 ren1->dst_entry,
1430 NULL,
1432 NULL,
1433 NULL);
1434 } else if ((dst_other.mode == ren1->pair->two->mode) &&
1435 sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
1437 * Added file on the other side identical to
1438 * the file being renamed: clean merge.
1439 * Also, there is no need to overwrite the
1440 * file already in the working copy, so call
1441 * update_file_flags() instead of
1442 * update_file().
1444 update_file_flags(o,
1445 ren1->pair->two->sha1,
1446 ren1->pair->two->mode,
1447 ren1_dst,
1448 1, /* update_cache */
1449 0 /* update_wd */);
1450 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1451 clean_merge = 0;
1452 try_merge = 1;
1453 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
1454 "%s added in %s",
1455 ren1_src, ren1_dst, branch1,
1456 ren1_dst, branch2);
1457 if (o->call_depth) {
1458 struct merge_file_info mfi;
1459 mfi = merge_file(o, ren1_dst, null_sha1, 0,
1460 ren1->pair->two->sha1, ren1->pair->two->mode,
1461 dst_other.sha1, dst_other.mode,
1462 branch1, branch2);
1463 output(o, 1, "Adding merged %s", ren1_dst);
1464 update_file(o, 0, mfi.sha, mfi.mode, ren1_dst);
1465 try_merge = 0;
1466 } else {
1467 char *new_path = unique_path(o, ren1_dst, branch2);
1468 output(o, 1, "Adding as %s instead", new_path);
1469 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
1470 free(new_path);
1472 } else
1473 try_merge = 1;
1475 if (try_merge) {
1476 struct diff_filespec *one, *a, *b;
1477 src_other.path = (char *)ren1_src;
1479 one = ren1->pair->one;
1480 if (a_renames == renames1) {
1481 a = ren1->pair->two;
1482 b = &src_other;
1483 } else {
1484 b = ren1->pair->two;
1485 a = &src_other;
1487 update_entry(ren1->dst_entry, one, a, b);
1488 setup_rename_conflict_info(RENAME_NORMAL,
1489 ren1->pair,
1490 NULL,
1491 branch1,
1492 NULL,
1493 ren1->dst_entry,
1494 NULL,
1496 NULL,
1497 NULL);
1501 string_list_clear(&a_by_dst, 0);
1502 string_list_clear(&b_by_dst, 0);
1504 return clean_merge;
1507 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1509 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1512 static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1514 void *buf;
1515 enum object_type type;
1516 unsigned long size;
1517 buf = read_sha1_file(sha1, &type, &size);
1518 if (!buf)
1519 return error("cannot read object %s", sha1_to_hex(sha1));
1520 if (type != OBJ_BLOB) {
1521 free(buf);
1522 return error("object %s is not a blob", sha1_to_hex(sha1));
1524 strbuf_attach(dst, buf, size, size + 1);
1525 return 0;
1528 static int blob_unchanged(const unsigned char *o_sha,
1529 const unsigned char *a_sha,
1530 int renormalize, const char *path)
1532 struct strbuf o = STRBUF_INIT;
1533 struct strbuf a = STRBUF_INIT;
1534 int ret = 0; /* assume changed for safety */
1536 if (sha_eq(o_sha, a_sha))
1537 return 1;
1538 if (!renormalize)
1539 return 0;
1541 assert(o_sha && a_sha);
1542 if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1543 goto error_return;
1545 * Note: binary | is used so that both renormalizations are
1546 * performed. Comparison can be skipped if both files are
1547 * unchanged since their sha1s have already been compared.
1549 if (renormalize_buffer(path, o.buf, o.len, &o) |
1550 renormalize_buffer(path, a.buf, o.len, &a))
1551 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1553 error_return:
1554 strbuf_release(&o);
1555 strbuf_release(&a);
1556 return ret;
1559 static void handle_modify_delete(struct merge_options *o,
1560 const char *path,
1561 unsigned char *o_sha, int o_mode,
1562 unsigned char *a_sha, int a_mode,
1563 unsigned char *b_sha, int b_mode)
1565 handle_change_delete(o,
1566 path,
1567 o_sha, o_mode,
1568 a_sha, a_mode,
1569 b_sha, b_mode,
1570 "modify", "modified");
1573 static int merge_content(struct merge_options *o,
1574 const char *path,
1575 unsigned char *o_sha, int o_mode,
1576 unsigned char *a_sha, int a_mode,
1577 unsigned char *b_sha, int b_mode,
1578 struct rename_conflict_info *rename_conflict_info)
1580 const char *reason = "content";
1581 const char *path1 = NULL, *path2 = NULL;
1582 struct merge_file_info mfi;
1583 struct diff_filespec one, a, b;
1584 unsigned df_conflict_remains = 0;
1586 if (!o_sha) {
1587 reason = "add/add";
1588 o_sha = (unsigned char *)null_sha1;
1590 one.path = a.path = b.path = (char *)path;
1591 hashcpy(one.sha1, o_sha);
1592 one.mode = o_mode;
1593 hashcpy(a.sha1, a_sha);
1594 a.mode = a_mode;
1595 hashcpy(b.sha1, b_sha);
1596 b.mode = b_mode;
1598 if (rename_conflict_info) {
1599 struct diff_filepair *pair1 = rename_conflict_info->pair1;
1601 path1 = (o->branch1 == rename_conflict_info->branch1) ?
1602 pair1->two->path : pair1->one->path;
1603 /* If rename_conflict_info->pair2 != NULL, we are in
1604 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
1605 * normal rename.
1607 path2 = (rename_conflict_info->pair2 ||
1608 o->branch2 == rename_conflict_info->branch1) ?
1609 pair1->two->path : pair1->one->path;
1611 if (dir_in_way(path, !o->call_depth))
1612 df_conflict_remains = 1;
1614 mfi = merge_file_special_markers(o, &one, &a, &b,
1615 o->branch1, path1,
1616 o->branch2, path2);
1618 if (mfi.clean && !df_conflict_remains &&
1619 sha_eq(mfi.sha, a_sha) && mfi.mode == a_mode) {
1620 int path_renamed_outside_HEAD;
1621 output(o, 3, "Skipped %s (merged same as existing)", path);
1623 * The content merge resulted in the same file contents we
1624 * already had. We can return early if those file contents
1625 * are recorded at the correct path (which may not be true
1626 * if the merge involves a rename).
1628 path_renamed_outside_HEAD = !path2 || !strcmp(path, path2);
1629 if (!path_renamed_outside_HEAD) {
1630 add_cacheinfo(mfi.mode, mfi.sha, path,
1631 0, (!o->call_depth), 0);
1632 return mfi.clean;
1634 } else
1635 output(o, 2, "Auto-merging %s", path);
1637 if (!mfi.clean) {
1638 if (S_ISGITLINK(mfi.mode))
1639 reason = "submodule";
1640 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1641 reason, path);
1642 if (rename_conflict_info && !df_conflict_remains)
1643 update_stages(path, &one, &a, &b);
1646 if (df_conflict_remains) {
1647 char *new_path;
1648 if (o->call_depth) {
1649 remove_file_from_cache(path);
1650 } else {
1651 if (!mfi.clean)
1652 update_stages(path, &one, &a, &b);
1653 else {
1654 int file_from_stage2 = was_tracked(path);
1655 struct diff_filespec merged;
1656 hashcpy(merged.sha1, mfi.sha);
1657 merged.mode = mfi.mode;
1659 update_stages(path, NULL,
1660 file_from_stage2 ? &merged : NULL,
1661 file_from_stage2 ? NULL : &merged);
1665 new_path = unique_path(o, path, rename_conflict_info->branch1);
1666 output(o, 1, "Adding as %s instead", new_path);
1667 update_file(o, 0, mfi.sha, mfi.mode, new_path);
1668 free(new_path);
1669 mfi.clean = 0;
1670 } else {
1671 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1673 return mfi.clean;
1677 /* Per entry merge function */
1678 static int process_entry(struct merge_options *o,
1679 const char *path, struct stage_data *entry)
1682 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1683 print_index_entry("\tpath: ", entry);
1685 int clean_merge = 1;
1686 int normalize = o->renormalize;
1687 unsigned o_mode = entry->stages[1].mode;
1688 unsigned a_mode = entry->stages[2].mode;
1689 unsigned b_mode = entry->stages[3].mode;
1690 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1691 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1692 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1694 entry->processed = 1;
1695 if (entry->rename_conflict_info) {
1696 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
1697 switch (conflict_info->rename_type) {
1698 case RENAME_NORMAL:
1699 case RENAME_ONE_FILE_TO_ONE:
1700 clean_merge = merge_content(o, path,
1701 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1702 conflict_info);
1703 break;
1704 case RENAME_DELETE:
1705 clean_merge = 0;
1706 conflict_rename_delete(o, conflict_info->pair1,
1707 conflict_info->branch1,
1708 conflict_info->branch2);
1709 break;
1710 case RENAME_ONE_FILE_TO_TWO:
1711 clean_merge = 0;
1712 conflict_rename_rename_1to2(o, conflict_info);
1713 break;
1714 case RENAME_TWO_FILES_TO_ONE:
1715 clean_merge = 0;
1716 conflict_rename_rename_2to1(o, conflict_info);
1717 break;
1718 default:
1719 entry->processed = 0;
1720 break;
1722 } else if (o_sha && (!a_sha || !b_sha)) {
1723 /* Case A: Deleted in one */
1724 if ((!a_sha && !b_sha) ||
1725 (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1726 (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1727 /* Deleted in both or deleted in one and
1728 * unchanged in the other */
1729 if (a_sha)
1730 output(o, 2, "Removing %s", path);
1731 /* do not touch working file if it did not exist */
1732 remove_file(o, 1, path, !a_sha);
1733 } else {
1734 /* Modify/delete; deleted side may have put a directory in the way */
1735 clean_merge = 0;
1736 handle_modify_delete(o, path, o_sha, o_mode,
1737 a_sha, a_mode, b_sha, b_mode);
1739 } else if ((!o_sha && a_sha && !b_sha) ||
1740 (!o_sha && !a_sha && b_sha)) {
1741 /* Case B: Added in one. */
1742 /* [nothing|directory] -> ([nothing|directory], file) */
1744 const char *add_branch;
1745 const char *other_branch;
1746 unsigned mode;
1747 const unsigned char *sha;
1748 const char *conf;
1750 if (a_sha) {
1751 add_branch = o->branch1;
1752 other_branch = o->branch2;
1753 mode = a_mode;
1754 sha = a_sha;
1755 conf = "file/directory";
1756 } else {
1757 add_branch = o->branch2;
1758 other_branch = o->branch1;
1759 mode = b_mode;
1760 sha = b_sha;
1761 conf = "directory/file";
1763 if (dir_in_way(path, !o->call_depth)) {
1764 char *new_path = unique_path(o, path, add_branch);
1765 clean_merge = 0;
1766 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1767 "Adding %s as %s",
1768 conf, path, other_branch, path, new_path);
1769 if (o->call_depth)
1770 remove_file_from_cache(path);
1771 update_file(o, 0, sha, mode, new_path);
1772 if (o->call_depth)
1773 remove_file_from_cache(path);
1774 free(new_path);
1775 } else {
1776 output(o, 2, "Adding %s", path);
1777 /* do not overwrite file if already present */
1778 update_file_flags(o, sha, mode, path, 1, !a_sha);
1780 } else if (a_sha && b_sha) {
1781 /* Case C: Added in both (check for same permissions) and */
1782 /* case D: Modified in both, but differently. */
1783 clean_merge = merge_content(o, path,
1784 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1785 NULL);
1786 } else if (!o_sha && !a_sha && !b_sha) {
1788 * this entry was deleted altogether. a_mode == 0 means
1789 * we had that path and want to actively remove it.
1791 remove_file(o, 1, path, !a_mode);
1792 } else
1793 die("Fatal merge failure, shouldn't happen.");
1795 return clean_merge;
1798 int merge_trees(struct merge_options *o,
1799 struct tree *head,
1800 struct tree *merge,
1801 struct tree *common,
1802 struct tree **result)
1804 int code, clean;
1806 if (o->subtree_shift) {
1807 merge = shift_tree_object(head, merge, o->subtree_shift);
1808 common = shift_tree_object(head, common, o->subtree_shift);
1811 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1812 output(o, 0, "Already up-to-date!");
1813 *result = head;
1814 return 1;
1817 code = git_merge_trees(o->call_depth, common, head, merge);
1819 if (code != 0) {
1820 if (show(o, 4) || o->call_depth)
1821 die("merging of trees %s and %s failed",
1822 sha1_to_hex(head->object.sha1),
1823 sha1_to_hex(merge->object.sha1));
1824 else
1825 exit(128);
1828 if (unmerged_cache()) {
1829 struct string_list *entries, *re_head, *re_merge;
1830 int i;
1831 string_list_clear(&o->current_file_set, 1);
1832 string_list_clear(&o->current_directory_set, 1);
1833 get_files_dirs(o, head);
1834 get_files_dirs(o, merge);
1836 entries = get_unmerged();
1837 record_df_conflict_files(o, entries);
1838 re_head = get_renames(o, head, common, head, merge, entries);
1839 re_merge = get_renames(o, merge, common, head, merge, entries);
1840 clean = process_renames(o, re_head, re_merge);
1841 for (i = entries->nr-1; 0 <= i; i--) {
1842 const char *path = entries->items[i].string;
1843 struct stage_data *e = entries->items[i].util;
1844 if (!e->processed
1845 && !process_entry(o, path, e))
1846 clean = 0;
1848 for (i = 0; i < entries->nr; i++) {
1849 struct stage_data *e = entries->items[i].util;
1850 if (!e->processed)
1851 die("Unprocessed path??? %s",
1852 entries->items[i].string);
1855 string_list_clear(re_merge, 0);
1856 string_list_clear(re_head, 0);
1857 string_list_clear(entries, 1);
1860 else
1861 clean = 1;
1863 if (o->call_depth)
1864 *result = write_tree_from_memory(o);
1866 return clean;
1869 static struct commit_list *reverse_commit_list(struct commit_list *list)
1871 struct commit_list *next = NULL, *current, *backup;
1872 for (current = list; current; current = backup) {
1873 backup = current->next;
1874 current->next = next;
1875 next = current;
1877 return next;
1881 * Merge the commits h1 and h2, return the resulting virtual
1882 * commit object and a flag indicating the cleanness of the merge.
1884 int merge_recursive(struct merge_options *o,
1885 struct commit *h1,
1886 struct commit *h2,
1887 struct commit_list *ca,
1888 struct commit **result)
1890 struct commit_list *iter;
1891 struct commit *merged_common_ancestors;
1892 struct tree *mrtree = mrtree;
1893 int clean;
1895 if (show(o, 4)) {
1896 output(o, 4, "Merging:");
1897 output_commit_title(o, h1);
1898 output_commit_title(o, h2);
1901 if (!ca) {
1902 ca = get_merge_bases(h1, h2, 1);
1903 ca = reverse_commit_list(ca);
1906 if (show(o, 5)) {
1907 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1908 for (iter = ca; iter; iter = iter->next)
1909 output_commit_title(o, iter->item);
1912 merged_common_ancestors = pop_commit(&ca);
1913 if (merged_common_ancestors == NULL) {
1914 /* if there is no common ancestor, use an empty tree */
1915 struct tree *tree;
1917 tree = lookup_tree((const unsigned char *)EMPTY_TREE_SHA1_BIN);
1918 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1921 for (iter = ca; iter; iter = iter->next) {
1922 const char *saved_b1, *saved_b2;
1923 o->call_depth++;
1925 * When the merge fails, the result contains files
1926 * with conflict markers. The cleanness flag is
1927 * ignored, it was never actually used, as result of
1928 * merge_trees has always overwritten it: the committed
1929 * "conflicts" were already resolved.
1931 discard_cache();
1932 saved_b1 = o->branch1;
1933 saved_b2 = o->branch2;
1934 o->branch1 = "Temporary merge branch 1";
1935 o->branch2 = "Temporary merge branch 2";
1936 merge_recursive(o, merged_common_ancestors, iter->item,
1937 NULL, &merged_common_ancestors);
1938 o->branch1 = saved_b1;
1939 o->branch2 = saved_b2;
1940 o->call_depth--;
1942 if (!merged_common_ancestors)
1943 die("merge returned no commit");
1946 discard_cache();
1947 if (!o->call_depth)
1948 read_cache();
1950 o->ancestor = "merged common ancestors";
1951 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1952 &mrtree);
1954 if (o->call_depth) {
1955 *result = make_virtual_commit(mrtree, "merged tree");
1956 commit_list_insert(h1, &(*result)->parents);
1957 commit_list_insert(h2, &(*result)->parents->next);
1959 flush_output(o);
1960 if (show(o, 2))
1961 diff_warn_rename_limit("merge.renamelimit",
1962 o->needed_rename_limit, 0);
1963 return clean;
1966 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1968 struct object *object;
1970 object = deref_tag(parse_object(sha1), name, strlen(name));
1971 if (!object)
1972 return NULL;
1973 if (object->type == OBJ_TREE)
1974 return make_virtual_commit((struct tree*)object, name);
1975 if (object->type != OBJ_COMMIT)
1976 return NULL;
1977 if (parse_commit((struct commit *)object))
1978 return NULL;
1979 return (struct commit *)object;
1982 int merge_recursive_generic(struct merge_options *o,
1983 const unsigned char *head,
1984 const unsigned char *merge,
1985 int num_base_list,
1986 const unsigned char **base_list,
1987 struct commit **result)
1989 int clean, index_fd;
1990 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1991 struct commit *head_commit = get_ref(head, o->branch1);
1992 struct commit *next_commit = get_ref(merge, o->branch2);
1993 struct commit_list *ca = NULL;
1995 if (base_list) {
1996 int i;
1997 for (i = 0; i < num_base_list; ++i) {
1998 struct commit *base;
1999 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
2000 return error("Could not parse object '%s'",
2001 sha1_to_hex(base_list[i]));
2002 commit_list_insert(base, &ca);
2006 index_fd = hold_locked_index(lock, 1);
2007 clean = merge_recursive(o, head_commit, next_commit, ca,
2008 result);
2009 if (active_cache_changed &&
2010 (write_cache(index_fd, active_cache, active_nr) ||
2011 commit_locked_index(lock)))
2012 return error("Unable to write index.");
2014 return clean ? 0 : 1;
2017 static int merge_recursive_config(const char *var, const char *value, void *cb)
2019 struct merge_options *o = cb;
2020 if (!strcmp(var, "merge.verbosity")) {
2021 o->verbosity = git_config_int(var, value);
2022 return 0;
2024 if (!strcmp(var, "diff.renamelimit")) {
2025 o->diff_rename_limit = git_config_int(var, value);
2026 return 0;
2028 if (!strcmp(var, "merge.renamelimit")) {
2029 o->merge_rename_limit = git_config_int(var, value);
2030 return 0;
2032 return git_xmerge_config(var, value, cb);
2035 void init_merge_options(struct merge_options *o)
2037 memset(o, 0, sizeof(struct merge_options));
2038 o->verbosity = 2;
2039 o->buffer_output = 1;
2040 o->diff_rename_limit = -1;
2041 o->merge_rename_limit = -1;
2042 o->renormalize = 0;
2043 git_config(merge_recursive_config, o);
2044 if (getenv("GIT_MERGE_VERBOSITY"))
2045 o->verbosity =
2046 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
2047 if (o->verbosity >= 5)
2048 o->buffer_output = 0;
2049 strbuf_init(&o->obuf, 0);
2050 memset(&o->current_file_set, 0, sizeof(struct string_list));
2051 o->current_file_set.strdup_strings = 1;
2052 memset(&o->current_directory_set, 0, sizeof(struct string_list));
2053 o->current_directory_set.strdup_strings = 1;
2054 memset(&o->df_conflict_file_set, 0, sizeof(struct string_list));
2055 o->df_conflict_file_set.strdup_strings = 1;
2058 int parse_merge_opt(struct merge_options *o, const char *s)
2060 if (!s || !*s)
2061 return -1;
2062 if (!strcmp(s, "ours"))
2063 o->recursive_variant = MERGE_RECURSIVE_OURS;
2064 else if (!strcmp(s, "theirs"))
2065 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
2066 else if (!strcmp(s, "subtree"))
2067 o->subtree_shift = "";
2068 else if (!prefixcmp(s, "subtree="))
2069 o->subtree_shift = s + strlen("subtree=");
2070 else if (!strcmp(s, "patience"))
2071 o->xdl_opts |= XDF_PATIENCE_DIFF;
2072 else if (!strcmp(s, "histogram"))
2073 o->xdl_opts |= XDF_HISTOGRAM_DIFF;
2074 else if (!strcmp(s, "ignore-space-change"))
2075 o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2076 else if (!strcmp(s, "ignore-all-space"))
2077 o->xdl_opts |= XDF_IGNORE_WHITESPACE;
2078 else if (!strcmp(s, "ignore-space-at-eol"))
2079 o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2080 else if (!strcmp(s, "renormalize"))
2081 o->renormalize = 1;
2082 else if (!strcmp(s, "no-renormalize"))
2083 o->renormalize = 0;
2084 else if (!prefixcmp(s, "rename-threshold=")) {
2085 const char *score = s + strlen("rename-threshold=");
2086 if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
2087 return -1;
2089 else
2090 return -1;
2091 return 0;