acc2f64a4e9d03f49165e3c46396ce00a09dc6bd
[git/git.git] / merge-recursive.c
1 /*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6 #include "cache.h"
7 #include "config.h"
8 #include "advice.h"
9 #include "lockfile.h"
10 #include "cache-tree.h"
11 #include "object-store.h"
12 #include "repository.h"
13 #include "commit.h"
14 #include "blob.h"
15 #include "builtin.h"
16 #include "tree-walk.h"
17 #include "diff.h"
18 #include "diffcore.h"
19 #include "tag.h"
20 #include "alloc.h"
21 #include "unpack-trees.h"
22 #include "string-list.h"
23 #include "xdiff-interface.h"
24 #include "ll-merge.h"
25 #include "attr.h"
26 #include "merge-recursive.h"
27 #include "dir.h"
28 #include "submodule.h"
29 #include "revision.h"
30 #include "commit-reach.h"
31
32 struct path_hashmap_entry {
33 struct hashmap_entry e;
34 char path[FLEX_ARRAY];
35 };
36
37 static int path_hashmap_cmp(const void *cmp_data,
38 const void *entry,
39 const void *entry_or_key,
40 const void *keydata)
41 {
42 const struct path_hashmap_entry *a = entry;
43 const struct path_hashmap_entry *b = entry_or_key;
44 const char *key = keydata;
45
46 if (ignore_case)
47 return strcasecmp(a->path, key ? key : b->path);
48 else
49 return strcmp(a->path, key ? key : b->path);
50 }
51
52 static unsigned int path_hash(const char *path)
53 {
54 return ignore_case ? strihash(path) : strhash(path);
55 }
56
57 static struct dir_rename_entry *dir_rename_find_entry(struct hashmap *hashmap,
58 char *dir)
59 {
60 struct dir_rename_entry key;
61
62 if (dir == NULL)
63 return NULL;
64 hashmap_entry_init(&key, strhash(dir));
65 key.dir = dir;
66 return hashmap_get(hashmap, &key, NULL);
67 }
68
69 static int dir_rename_cmp(const void *unused_cmp_data,
70 const void *entry,
71 const void *entry_or_key,
72 const void *unused_keydata)
73 {
74 const struct dir_rename_entry *e1 = entry;
75 const struct dir_rename_entry *e2 = entry_or_key;
76
77 return strcmp(e1->dir, e2->dir);
78 }
79
80 static void dir_rename_init(struct hashmap *map)
81 {
82 hashmap_init(map, dir_rename_cmp, NULL, 0);
83 }
84
85 static void dir_rename_entry_init(struct dir_rename_entry *entry,
86 char *directory)
87 {
88 hashmap_entry_init(entry, strhash(directory));
89 entry->dir = directory;
90 entry->non_unique_new_dir = 0;
91 strbuf_init(&entry->new_dir, 0);
92 string_list_init(&entry->possible_new_dirs, 0);
93 }
94
95 static struct collision_entry *collision_find_entry(struct hashmap *hashmap,
96 char *target_file)
97 {
98 struct collision_entry key;
99
100 hashmap_entry_init(&key, strhash(target_file));
101 key.target_file = target_file;
102 return hashmap_get(hashmap, &key, NULL);
103 }
104
105 static int collision_cmp(void *unused_cmp_data,
106 const struct collision_entry *e1,
107 const struct collision_entry *e2,
108 const void *unused_keydata)
109 {
110 return strcmp(e1->target_file, e2->target_file);
111 }
112
113 static void collision_init(struct hashmap *map)
114 {
115 hashmap_init(map, (hashmap_cmp_fn) collision_cmp, NULL, 0);
116 }
117
118 static void flush_output(struct merge_options *o)
119 {
120 if (o->buffer_output < 2 && o->obuf.len) {
121 fputs(o->obuf.buf, stdout);
122 strbuf_reset(&o->obuf);
123 }
124 }
125
126 static int err(struct merge_options *o, const char *err, ...)
127 {
128 va_list params;
129
130 if (o->buffer_output < 2)
131 flush_output(o);
132 else {
133 strbuf_complete(&o->obuf, '\n');
134 strbuf_addstr(&o->obuf, "error: ");
135 }
136 va_start(params, err);
137 strbuf_vaddf(&o->obuf, err, params);
138 va_end(params);
139 if (o->buffer_output > 1)
140 strbuf_addch(&o->obuf, '\n');
141 else {
142 error("%s", o->obuf.buf);
143 strbuf_reset(&o->obuf);
144 }
145
146 return -1;
147 }
148
149 static struct tree *shift_tree_object(struct tree *one, struct tree *two,
150 const char *subtree_shift)
151 {
152 struct object_id shifted;
153
154 if (!*subtree_shift) {
155 shift_tree(&one->object.oid, &two->object.oid, &shifted, 0);
156 } else {
157 shift_tree_by(&one->object.oid, &two->object.oid, &shifted,
158 subtree_shift);
159 }
160 if (oideq(&two->object.oid, &shifted))
161 return two;
162 return lookup_tree(the_repository, &shifted);
163 }
164
165 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
166 {
167 struct commit *commit = alloc_commit_node(the_repository);
168
169 set_merge_remote_desc(commit, comment, (struct object *)commit);
170 commit->maybe_tree = tree;
171 commit->object.parsed = 1;
172 return commit;
173 }
174
175 /*
176 * Since we use get_tree_entry(), which does not put the read object into
177 * the object pool, we cannot rely on a == b.
178 */
179 static int oid_eq(const struct object_id *a, const struct object_id *b)
180 {
181 if (!a && !b)
182 return 2;
183 return a && b && oideq(a, b);
184 }
185
186 enum rename_type {
187 RENAME_NORMAL = 0,
188 RENAME_VIA_DIR,
189 RENAME_DELETE,
190 RENAME_ONE_FILE_TO_ONE,
191 RENAME_ONE_FILE_TO_TWO,
192 RENAME_TWO_FILES_TO_ONE
193 };
194
195 struct rename_conflict_info {
196 enum rename_type rename_type;
197 struct diff_filepair *pair1;
198 struct diff_filepair *pair2;
199 const char *branch1;
200 const char *branch2;
201 struct stage_data *dst_entry1;
202 struct stage_data *dst_entry2;
203 struct diff_filespec ren1_other;
204 struct diff_filespec ren2_other;
205 };
206
207 /*
208 * Since we want to write the index eventually, we cannot reuse the index
209 * for these (temporary) data.
210 */
211 struct stage_data {
212 struct {
213 unsigned mode;
214 struct object_id oid;
215 } stages[4];
216 struct rename_conflict_info *rename_conflict_info;
217 unsigned processed:1;
218 };
219
220 static inline void setup_rename_conflict_info(enum rename_type rename_type,
221 struct diff_filepair *pair1,
222 struct diff_filepair *pair2,
223 const char *branch1,
224 const char *branch2,
225 struct stage_data *dst_entry1,
226 struct stage_data *dst_entry2,
227 struct merge_options *o,
228 struct stage_data *src_entry1,
229 struct stage_data *src_entry2)
230 {
231 struct rename_conflict_info *ci;
232
233 /*
234 * When we have two renames involved, it's easiest to get the
235 * correct things into stage 2 and 3, and to make sure that the
236 * content merge puts HEAD before the other branch if we just
237 * ensure that branch1 == o->branch1. So, simply flip arguments
238 * around if we don't have that.
239 */
240 if (dst_entry2 && branch1 != o->branch1) {
241 setup_rename_conflict_info(rename_type,
242 pair2, pair1,
243 branch2, branch1,
244 dst_entry2, dst_entry1,
245 o,
246 src_entry2, src_entry1);
247 return;
248 }
249
250 ci = xcalloc(1, sizeof(struct rename_conflict_info));
251 ci->rename_type = rename_type;
252 ci->pair1 = pair1;
253 ci->branch1 = branch1;
254 ci->branch2 = branch2;
255
256 ci->dst_entry1 = dst_entry1;
257 dst_entry1->rename_conflict_info = ci;
258 dst_entry1->processed = 0;
259
260 assert(!pair2 == !dst_entry2);
261 if (dst_entry2) {
262 ci->dst_entry2 = dst_entry2;
263 ci->pair2 = pair2;
264 dst_entry2->rename_conflict_info = ci;
265 }
266
267 if (rename_type == RENAME_TWO_FILES_TO_ONE) {
268 /*
269 * For each rename, there could have been
270 * modifications on the side of history where that
271 * file was not renamed.
272 */
273 int ostage1 = o->branch1 == branch1 ? 3 : 2;
274 int ostage2 = ostage1 ^ 1;
275
276 ci->ren1_other.path = pair1->one->path;
277 oidcpy(&ci->ren1_other.oid, &src_entry1->stages[ostage1].oid);
278 ci->ren1_other.mode = src_entry1->stages[ostage1].mode;
279
280 ci->ren2_other.path = pair2->one->path;
281 oidcpy(&ci->ren2_other.oid, &src_entry2->stages[ostage2].oid);
282 ci->ren2_other.mode = src_entry2->stages[ostage2].mode;
283 }
284 }
285
286 static int show(struct merge_options *o, int v)
287 {
288 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
289 }
290
291 __attribute__((format (printf, 3, 4)))
292 static void output(struct merge_options *o, int v, const char *fmt, ...)
293 {
294 va_list ap;
295
296 if (!show(o, v))
297 return;
298
299 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
300
301 va_start(ap, fmt);
302 strbuf_vaddf(&o->obuf, fmt, ap);
303 va_end(ap);
304
305 strbuf_addch(&o->obuf, '\n');
306 if (!o->buffer_output)
307 flush_output(o);
308 }
309
310 static void output_commit_title(struct merge_options *o, struct commit *commit)
311 {
312 struct merge_remote_desc *desc;
313
314 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
315 desc = merge_remote_util(commit);
316 if (desc)
317 strbuf_addf(&o->obuf, "virtual %s\n", desc->name);
318 else {
319 strbuf_add_unique_abbrev(&o->obuf, &commit->object.oid,
320 DEFAULT_ABBREV);
321 strbuf_addch(&o->obuf, ' ');
322 if (parse_commit(commit) != 0)
323 strbuf_addstr(&o->obuf, _("(bad commit)\n"));
324 else {
325 const char *title;
326 const char *msg = get_commit_buffer(commit, NULL);
327 int len = find_commit_subject(msg, &title);
328 if (len)
329 strbuf_addf(&o->obuf, "%.*s\n", len, title);
330 unuse_commit_buffer(commit, msg);
331 }
332 }
333 flush_output(o);
334 }
335
336 static int add_cacheinfo(struct merge_options *o,
337 unsigned int mode, const struct object_id *oid,
338 const char *path, int stage, int refresh, int options)
339 {
340 struct cache_entry *ce;
341 int ret;
342
343 ce = make_cache_entry(&the_index, mode, oid ? oid : &null_oid, path, stage, 0);
344 if (!ce)
345 return err(o, _("add_cacheinfo failed for path '%s'; merge aborting."), path);
346
347 ret = add_cache_entry(ce, options);
348 if (refresh) {
349 struct cache_entry *nce;
350
351 nce = refresh_cache_entry(&the_index, ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
352 if (!nce)
353 return err(o, _("add_cacheinfo failed to refresh for path '%s'; merge aborting."), path);
354 if (nce != ce)
355 ret = add_cache_entry(nce, options);
356 }
357 return ret;
358 }
359
360 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
361 {
362 parse_tree(tree);
363 init_tree_desc(desc, tree->buffer, tree->size);
364 }
365
366 static int unpack_trees_start(struct merge_options *o,
367 struct tree *common,
368 struct tree *head,
369 struct tree *merge)
370 {
371 int rc;
372 struct tree_desc t[3];
373 struct index_state tmp_index = { NULL };
374
375 memset(&o->unpack_opts, 0, sizeof(o->unpack_opts));
376 if (o->call_depth)
377 o->unpack_opts.index_only = 1;
378 else
379 o->unpack_opts.update = 1;
380 o->unpack_opts.merge = 1;
381 o->unpack_opts.head_idx = 2;
382 o->unpack_opts.fn = threeway_merge;
383 o->unpack_opts.src_index = &the_index;
384 o->unpack_opts.dst_index = &tmp_index;
385 o->unpack_opts.aggressive = !merge_detect_rename(o);
386 setup_unpack_trees_porcelain(&o->unpack_opts, "merge");
387
388 init_tree_desc_from_tree(t+0, common);
389 init_tree_desc_from_tree(t+1, head);
390 init_tree_desc_from_tree(t+2, merge);
391
392 rc = unpack_trees(3, t, &o->unpack_opts);
393 cache_tree_free(&active_cache_tree);
394
395 /*
396 * Update the_index to match the new results, AFTER saving a copy
397 * in o->orig_index. Update src_index to point to the saved copy.
398 * (verify_uptodate() checks src_index, and the original index is
399 * the one that had the necessary modification timestamps.)
400 */
401 o->orig_index = the_index;
402 the_index = tmp_index;
403 o->unpack_opts.src_index = &o->orig_index;
404
405 return rc;
406 }
407
408 static void unpack_trees_finish(struct merge_options *o)
409 {
410 discard_index(&o->orig_index);
411 clear_unpack_trees_porcelain(&o->unpack_opts);
412 }
413
414 struct tree *write_tree_from_memory(struct merge_options *o)
415 {
416 struct tree *result = NULL;
417
418 if (unmerged_cache()) {
419 int i;
420 fprintf(stderr, "BUG: There are unmerged index entries:\n");
421 for (i = 0; i < active_nr; i++) {
422 const struct cache_entry *ce = active_cache[i];
423 if (ce_stage(ce))
424 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
425 (int)ce_namelen(ce), ce->name);
426 }
427 BUG("unmerged index entries in merge-recursive.c");
428 }
429
430 if (!active_cache_tree)
431 active_cache_tree = cache_tree();
432
433 if (!cache_tree_fully_valid(active_cache_tree) &&
434 cache_tree_update(&the_index, 0) < 0) {
435 err(o, _("error building trees"));
436 return NULL;
437 }
438
439 result = lookup_tree(the_repository, &active_cache_tree->oid);
440
441 return result;
442 }
443
444 static int save_files_dirs(const struct object_id *oid,
445 struct strbuf *base, const char *path,
446 unsigned int mode, int stage, void *context)
447 {
448 struct path_hashmap_entry *entry;
449 int baselen = base->len;
450 struct merge_options *o = context;
451
452 strbuf_addstr(base, path);
453
454 FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
455 hashmap_entry_init(entry, path_hash(entry->path));
456 hashmap_add(&o->current_file_dir_set, entry);
457
458 strbuf_setlen(base, baselen);
459 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
460 }
461
462 static void get_files_dirs(struct merge_options *o, struct tree *tree)
463 {
464 struct pathspec match_all;
465 memset(&match_all, 0, sizeof(match_all));
466 read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
467 }
468
469 static int get_tree_entry_if_blob(const struct object_id *tree,
470 const char *path,
471 struct object_id *hashy,
472 unsigned int *mode_o)
473 {
474 int ret;
475
476 ret = get_tree_entry(tree, path, hashy, mode_o);
477 if (S_ISDIR(*mode_o)) {
478 oidcpy(hashy, &null_oid);
479 *mode_o = 0;
480 }
481 return ret;
482 }
483
484 /*
485 * Returns an index_entry instance which doesn't have to correspond to
486 * a real cache entry in Git's index.
487 */
488 static struct stage_data *insert_stage_data(const char *path,
489 struct tree *o, struct tree *a, struct tree *b,
490 struct string_list *entries)
491 {
492 struct string_list_item *item;
493 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
494 get_tree_entry_if_blob(&o->object.oid, path,
495 &e->stages[1].oid, &e->stages[1].mode);
496 get_tree_entry_if_blob(&a->object.oid, path,
497 &e->stages[2].oid, &e->stages[2].mode);
498 get_tree_entry_if_blob(&b->object.oid, path,
499 &e->stages[3].oid, &e->stages[3].mode);
500 item = string_list_insert(entries, path);
501 item->util = e;
502 return e;
503 }
504
505 /*
506 * Create a dictionary mapping file names to stage_data objects. The
507 * dictionary contains one entry for every path with a non-zero stage entry.
508 */
509 static struct string_list *get_unmerged(void)
510 {
511 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
512 int i;
513
514 unmerged->strdup_strings = 1;
515
516 for (i = 0; i < active_nr; i++) {
517 struct string_list_item *item;
518 struct stage_data *e;
519 const struct cache_entry *ce = active_cache[i];
520 if (!ce_stage(ce))
521 continue;
522
523 item = string_list_lookup(unmerged, ce->name);
524 if (!item) {
525 item = string_list_insert(unmerged, ce->name);
526 item->util = xcalloc(1, sizeof(struct stage_data));
527 }
528 e = item->util;
529 e->stages[ce_stage(ce)].mode = ce->ce_mode;
530 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
531 }
532
533 return unmerged;
534 }
535
536 static int string_list_df_name_compare(const char *one, const char *two)
537 {
538 int onelen = strlen(one);
539 int twolen = strlen(two);
540 /*
541 * Here we only care that entries for D/F conflicts are
542 * adjacent, in particular with the file of the D/F conflict
543 * appearing before files below the corresponding directory.
544 * The order of the rest of the list is irrelevant for us.
545 *
546 * To achieve this, we sort with df_name_compare and provide
547 * the mode S_IFDIR so that D/F conflicts will sort correctly.
548 * We use the mode S_IFDIR for everything else for simplicity,
549 * since in other cases any changes in their order due to
550 * sorting cause no problems for us.
551 */
552 int cmp = df_name_compare(one, onelen, S_IFDIR,
553 two, twolen, S_IFDIR);
554 /*
555 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
556 * that 'foo' comes before 'foo/bar'.
557 */
558 if (cmp)
559 return cmp;
560 return onelen - twolen;
561 }
562
563 static void record_df_conflict_files(struct merge_options *o,
564 struct string_list *entries)
565 {
566 /* If there is a D/F conflict and the file for such a conflict
567 * currently exists in the working tree, we want to allow it to be
568 * removed to make room for the corresponding directory if needed.
569 * The files underneath the directories of such D/F conflicts will
570 * be processed before the corresponding file involved in the D/F
571 * conflict. If the D/F directory ends up being removed by the
572 * merge, then we won't have to touch the D/F file. If the D/F
573 * directory needs to be written to the working copy, then the D/F
574 * file will simply be removed (in make_room_for_path()) to make
575 * room for the necessary paths. Note that if both the directory
576 * and the file need to be present, then the D/F file will be
577 * reinstated with a new unique name at the time it is processed.
578 */
579 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
580 const char *last_file = NULL;
581 int last_len = 0;
582 int i;
583
584 /*
585 * If we're merging merge-bases, we don't want to bother with
586 * any working directory changes.
587 */
588 if (o->call_depth)
589 return;
590
591 /* Ensure D/F conflicts are adjacent in the entries list. */
592 for (i = 0; i < entries->nr; i++) {
593 struct string_list_item *next = &entries->items[i];
594 string_list_append(&df_sorted_entries, next->string)->util =
595 next->util;
596 }
597 df_sorted_entries.cmp = string_list_df_name_compare;
598 string_list_sort(&df_sorted_entries);
599
600 string_list_clear(&o->df_conflict_file_set, 1);
601 for (i = 0; i < df_sorted_entries.nr; i++) {
602 const char *path = df_sorted_entries.items[i].string;
603 int len = strlen(path);
604 struct stage_data *e = df_sorted_entries.items[i].util;
605
606 /*
607 * Check if last_file & path correspond to a D/F conflict;
608 * i.e. whether path is last_file+'/'+<something>.
609 * If so, record that it's okay to remove last_file to make
610 * room for path and friends if needed.
611 */
612 if (last_file &&
613 len > last_len &&
614 memcmp(path, last_file, last_len) == 0 &&
615 path[last_len] == '/') {
616 string_list_insert(&o->df_conflict_file_set, last_file);
617 }
618
619 /*
620 * Determine whether path could exist as a file in the
621 * working directory as a possible D/F conflict. This
622 * will only occur when it exists in stage 2 as a
623 * file.
624 */
625 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
626 last_file = path;
627 last_len = len;
628 } else {
629 last_file = NULL;
630 }
631 }
632 string_list_clear(&df_sorted_entries, 0);
633 }
634
635 struct rename {
636 struct diff_filepair *pair;
637 /*
638 * Purpose of src_entry and dst_entry:
639 *
640 * If 'before' is renamed to 'after' then src_entry will contain
641 * the versions of 'before' from the merge_base, HEAD, and MERGE in
642 * stages 1, 2, and 3; dst_entry will contain the respective
643 * versions of 'after' in corresponding locations. Thus, we have a
644 * total of six modes and oids, though some will be null. (Stage 0
645 * is ignored; we're interested in handling conflicts.)
646 *
647 * Since we don't turn on break-rewrites by default, neither
648 * src_entry nor dst_entry can have all three of their stages have
649 * non-null oids, meaning at most four of the six will be non-null.
650 * Also, since this is a rename, both src_entry and dst_entry will
651 * have at least one non-null oid, meaning at least two will be
652 * non-null. Of the six oids, a typical rename will have three be
653 * non-null. Only two implies a rename/delete, and four implies a
654 * rename/add.
655 */
656 struct stage_data *src_entry;
657 struct stage_data *dst_entry;
658 unsigned add_turned_into_rename:1;
659 unsigned processed:1;
660 };
661
662 static int update_stages(struct merge_options *opt, const char *path,
663 const struct diff_filespec *o,
664 const struct diff_filespec *a,
665 const struct diff_filespec *b)
666 {
667
668 /*
669 * NOTE: It is usually a bad idea to call update_stages on a path
670 * before calling update_file on that same path, since it can
671 * sometimes lead to spurious "refusing to lose untracked file..."
672 * messages from update_file (via make_room_for path via
673 * would_lose_untracked). Instead, reverse the order of the calls
674 * (executing update_file first and then update_stages).
675 */
676 int clear = 1;
677 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
678 if (clear)
679 if (remove_file_from_cache(path))
680 return -1;
681 if (o)
682 if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options))
683 return -1;
684 if (a)
685 if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options))
686 return -1;
687 if (b)
688 if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options))
689 return -1;
690 return 0;
691 }
692
693 static int update_stages_for_stage_data(struct merge_options *opt,
694 const char *path,
695 const struct stage_data *stage_data)
696 {
697 struct diff_filespec o, a, b;
698
699 o.mode = stage_data->stages[1].mode;
700 oidcpy(&o.oid, &stage_data->stages[1].oid);
701
702 a.mode = stage_data->stages[2].mode;
703 oidcpy(&a.oid, &stage_data->stages[2].oid);
704
705 b.mode = stage_data->stages[3].mode;
706 oidcpy(&b.oid, &stage_data->stages[3].oid);
707
708 return update_stages(opt, path,
709 is_null_oid(&o.oid) ? NULL : &o,
710 is_null_oid(&a.oid) ? NULL : &a,
711 is_null_oid(&b.oid) ? NULL : &b);
712 }
713
714 static void update_entry(struct stage_data *entry,
715 struct diff_filespec *o,
716 struct diff_filespec *a,
717 struct diff_filespec *b)
718 {
719 entry->processed = 0;
720 entry->stages[1].mode = o->mode;
721 entry->stages[2].mode = a->mode;
722 entry->stages[3].mode = b->mode;
723 oidcpy(&entry->stages[1].oid, &o->oid);
724 oidcpy(&entry->stages[2].oid, &a->oid);
725 oidcpy(&entry->stages[3].oid, &b->oid);
726 }
727
728 static int remove_file(struct merge_options *o, int clean,
729 const char *path, int no_wd)
730 {
731 int update_cache = o->call_depth || clean;
732 int update_working_directory = !o->call_depth && !no_wd;
733
734 if (update_cache) {
735 if (remove_file_from_cache(path))
736 return -1;
737 }
738 if (update_working_directory) {
739 if (ignore_case) {
740 struct cache_entry *ce;
741 ce = cache_file_exists(path, strlen(path), ignore_case);
742 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
743 return 0;
744 }
745 if (remove_path(path))
746 return -1;
747 }
748 return 0;
749 }
750
751 /* add a string to a strbuf, but converting "/" to "_" */
752 static void add_flattened_path(struct strbuf *out, const char *s)
753 {
754 size_t i = out->len;
755 strbuf_addstr(out, s);
756 for (; i < out->len; i++)
757 if (out->buf[i] == '/')
758 out->buf[i] = '_';
759 }
760
761 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
762 {
763 struct path_hashmap_entry *entry;
764 struct strbuf newpath = STRBUF_INIT;
765 int suffix = 0;
766 size_t base_len;
767
768 strbuf_addf(&newpath, "%s~", path);
769 add_flattened_path(&newpath, branch);
770
771 base_len = newpath.len;
772 while (hashmap_get_from_hash(&o->current_file_dir_set,
773 path_hash(newpath.buf), newpath.buf) ||
774 (!o->call_depth && file_exists(newpath.buf))) {
775 strbuf_setlen(&newpath, base_len);
776 strbuf_addf(&newpath, "_%d", suffix++);
777 }
778
779 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
780 hashmap_entry_init(entry, path_hash(entry->path));
781 hashmap_add(&o->current_file_dir_set, entry);
782 return strbuf_detach(&newpath, NULL);
783 }
784
785 /**
786 * Check whether a directory in the index is in the way of an incoming
787 * file. Return 1 if so. If check_working_copy is non-zero, also
788 * check the working directory. If empty_ok is non-zero, also return
789 * 0 in the case where the working-tree dir exists but is empty.
790 */
791 static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
792 {
793 int pos;
794 struct strbuf dirpath = STRBUF_INIT;
795 struct stat st;
796
797 strbuf_addstr(&dirpath, path);
798 strbuf_addch(&dirpath, '/');
799
800 pos = cache_name_pos(dirpath.buf, dirpath.len);
801
802 if (pos < 0)
803 pos = -1 - pos;
804 if (pos < active_nr &&
805 !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) {
806 strbuf_release(&dirpath);
807 return 1;
808 }
809
810 strbuf_release(&dirpath);
811 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
812 !(empty_ok && is_empty_dir(path));
813 }
814
815 /*
816 * Returns whether path was tracked in the index before the merge started,
817 * and its oid and mode match the specified values
818 */
819 static int was_tracked_and_matches(struct merge_options *o, const char *path,
820 const struct object_id *oid, unsigned mode)
821 {
822 int pos = index_name_pos(&o->orig_index, path, strlen(path));
823 struct cache_entry *ce;
824
825 if (0 > pos)
826 /* we were not tracking this path before the merge */
827 return 0;
828
829 /* See if the file we were tracking before matches */
830 ce = o->orig_index.cache[pos];
831 return (oid_eq(&ce->oid, oid) && ce->ce_mode == mode);
832 }
833
834 /*
835 * Returns whether path was tracked in the index before the merge started
836 */
837 static int was_tracked(struct merge_options *o, const char *path)
838 {
839 int pos = index_name_pos(&o->orig_index, path, strlen(path));
840
841 if (0 <= pos)
842 /* we were tracking this path before the merge */
843 return 1;
844
845 return 0;
846 }
847
848 static int would_lose_untracked(const char *path)
849 {
850 /*
851 * This may look like it can be simplified to:
852 * return !was_tracked(o, path) && file_exists(path)
853 * but it can't. This function needs to know whether path was in
854 * the working tree due to EITHER having been tracked in the index
855 * before the merge OR having been put into the working copy and
856 * index by unpack_trees(). Due to that either-or requirement, we
857 * check the current index instead of the original one.
858 *
859 * Note that we do not need to worry about merge-recursive itself
860 * updating the index after unpack_trees() and before calling this
861 * function, because we strictly require all code paths in
862 * merge-recursive to update the working tree first and the index
863 * second. Doing otherwise would break
864 * update_file()/would_lose_untracked(); see every comment in this
865 * file which mentions "update_stages".
866 */
867 int pos = cache_name_pos(path, strlen(path));
868
869 if (pos < 0)
870 pos = -1 - pos;
871 while (pos < active_nr &&
872 !strcmp(path, active_cache[pos]->name)) {
873 /*
874 * If stage #0, it is definitely tracked.
875 * If it has stage #2 then it was tracked
876 * before this merge started. All other
877 * cases the path was not tracked.
878 */
879 switch (ce_stage(active_cache[pos])) {
880 case 0:
881 case 2:
882 return 0;
883 }
884 pos++;
885 }
886 return file_exists(path);
887 }
888
889 static int was_dirty(struct merge_options *o, const char *path)
890 {
891 struct cache_entry *ce;
892 int dirty = 1;
893
894 if (o->call_depth || !was_tracked(o, path))
895 return !dirty;
896
897 ce = index_file_exists(o->unpack_opts.src_index,
898 path, strlen(path), ignore_case);
899 dirty = verify_uptodate(ce, &o->unpack_opts) != 0;
900 return dirty;
901 }
902
903 static int make_room_for_path(struct merge_options *o, const char *path)
904 {
905 int status, i;
906 const char *msg = _("failed to create path '%s'%s");
907
908 /* Unlink any D/F conflict files that are in the way */
909 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
910 const char *df_path = o->df_conflict_file_set.items[i].string;
911 size_t pathlen = strlen(path);
912 size_t df_pathlen = strlen(df_path);
913 if (df_pathlen < pathlen &&
914 path[df_pathlen] == '/' &&
915 strncmp(path, df_path, df_pathlen) == 0) {
916 output(o, 3,
917 _("Removing %s to make room for subdirectory\n"),
918 df_path);
919 unlink(df_path);
920 unsorted_string_list_delete_item(&o->df_conflict_file_set,
921 i, 0);
922 break;
923 }
924 }
925
926 /* Make sure leading directories are created */
927 status = safe_create_leading_directories_const(path);
928 if (status) {
929 if (status == SCLD_EXISTS)
930 /* something else exists */
931 return err(o, msg, path, _(": perhaps a D/F conflict?"));
932 return err(o, msg, path, "");
933 }
934
935 /*
936 * Do not unlink a file in the work tree if we are not
937 * tracking it.
938 */
939 if (would_lose_untracked(path))
940 return err(o, _("refusing to lose untracked file at '%s'"),
941 path);
942
943 /* Successful unlink is good.. */
944 if (!unlink(path))
945 return 0;
946 /* .. and so is no existing file */
947 if (errno == ENOENT)
948 return 0;
949 /* .. but not some other error (who really cares what?) */
950 return err(o, msg, path, _(": perhaps a D/F conflict?"));
951 }
952
953 static int update_file_flags(struct merge_options *o,
954 const struct object_id *oid,
955 unsigned mode,
956 const char *path,
957 int update_cache,
958 int update_wd)
959 {
960 int ret = 0;
961
962 if (o->call_depth)
963 update_wd = 0;
964
965 if (update_wd) {
966 enum object_type type;
967 void *buf;
968 unsigned long size;
969
970 if (S_ISGITLINK(mode)) {
971 /*
972 * We may later decide to recursively descend into
973 * the submodule directory and update its index
974 * and/or work tree, but we do not do that now.
975 */
976 update_wd = 0;
977 goto update_index;
978 }
979
980 buf = read_object_file(oid, &type, &size);
981 if (!buf)
982 return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path);
983 if (type != OBJ_BLOB) {
984 ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path);
985 goto free_buf;
986 }
987 if (S_ISREG(mode)) {
988 struct strbuf strbuf = STRBUF_INIT;
989 if (convert_to_working_tree(&the_index, path, buf, size, &strbuf)) {
990 free(buf);
991 size = strbuf.len;
992 buf = strbuf_detach(&strbuf, NULL);
993 }
994 }
995
996 if (make_room_for_path(o, path) < 0) {
997 update_wd = 0;
998 goto free_buf;
999 }
1000 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
1001 int fd;
1002 if (mode & 0100)
1003 mode = 0777;
1004 else
1005 mode = 0666;
1006 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
1007 if (fd < 0) {
1008 ret = err(o, _("failed to open '%s': %s"),
1009 path, strerror(errno));
1010 goto free_buf;
1011 }
1012 write_in_full(fd, buf, size);
1013 close(fd);
1014 } else if (S_ISLNK(mode)) {
1015 char *lnk = xmemdupz(buf, size);
1016 safe_create_leading_directories_const(path);
1017 unlink(path);
1018 if (symlink(lnk, path))
1019 ret = err(o, _("failed to symlink '%s': %s"),
1020 path, strerror(errno));
1021 free(lnk);
1022 } else
1023 ret = err(o,
1024 _("do not know what to do with %06o %s '%s'"),
1025 mode, oid_to_hex(oid), path);
1026 free_buf:
1027 free(buf);
1028 }
1029 update_index:
1030 if (!ret && update_cache)
1031 if (add_cacheinfo(o, mode, oid, path, 0, update_wd,
1032 ADD_CACHE_OK_TO_ADD))
1033 return -1;
1034 return ret;
1035 }
1036
1037 static int update_file(struct merge_options *o,
1038 int clean,
1039 const struct object_id *oid,
1040 unsigned mode,
1041 const char *path)
1042 {
1043 return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth);
1044 }
1045
1046 /* Low level file merging, update and removal */
1047
1048 struct merge_file_info {
1049 struct object_id oid;
1050 unsigned mode;
1051 unsigned clean:1,
1052 merge:1;
1053 };
1054
1055 static int merge_3way(struct merge_options *o,
1056 mmbuffer_t *result_buf,
1057 const struct diff_filespec *one,
1058 const struct diff_filespec *a,
1059 const struct diff_filespec *b,
1060 const char *branch1,
1061 const char *branch2)
1062 {
1063 mmfile_t orig, src1, src2;
1064 struct ll_merge_options ll_opts = {0};
1065 char *base_name, *name1, *name2;
1066 int merge_status;
1067
1068 ll_opts.renormalize = o->renormalize;
1069 ll_opts.xdl_opts = o->xdl_opts;
1070
1071 if (o->call_depth) {
1072 ll_opts.virtual_ancestor = 1;
1073 ll_opts.variant = 0;
1074 } else {
1075 switch (o->recursive_variant) {
1076 case MERGE_RECURSIVE_OURS:
1077 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
1078 break;
1079 case MERGE_RECURSIVE_THEIRS:
1080 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
1081 break;
1082 default:
1083 ll_opts.variant = 0;
1084 break;
1085 }
1086 }
1087
1088 if (strcmp(a->path, b->path) ||
1089 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
1090 base_name = o->ancestor == NULL ? NULL :
1091 mkpathdup("%s:%s", o->ancestor, one->path);
1092 name1 = mkpathdup("%s:%s", branch1, a->path);
1093 name2 = mkpathdup("%s:%s", branch2, b->path);
1094 } else {
1095 base_name = o->ancestor == NULL ? NULL :
1096 mkpathdup("%s", o->ancestor);
1097 name1 = mkpathdup("%s", branch1);
1098 name2 = mkpathdup("%s", branch2);
1099 }
1100
1101 read_mmblob(&orig, &one->oid);
1102 read_mmblob(&src1, &a->oid);
1103 read_mmblob(&src2, &b->oid);
1104
1105 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
1106 &src1, name1, &src2, name2,
1107 &the_index, &ll_opts);
1108
1109 free(base_name);
1110 free(name1);
1111 free(name2);
1112 free(orig.ptr);
1113 free(src1.ptr);
1114 free(src2.ptr);
1115 return merge_status;
1116 }
1117
1118 static int find_first_merges(struct object_array *result, const char *path,
1119 struct commit *a, struct commit *b)
1120 {
1121 int i, j;
1122 struct object_array merges = OBJECT_ARRAY_INIT;
1123 struct commit *commit;
1124 int contains_another;
1125
1126 char merged_revision[42];
1127 const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1128 "--all", merged_revision, NULL };
1129 struct rev_info revs;
1130 struct setup_revision_opt rev_opts;
1131
1132 memset(result, 0, sizeof(struct object_array));
1133 memset(&rev_opts, 0, sizeof(rev_opts));
1134
1135 /* get all revisions that merge commit a */
1136 xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1137 oid_to_hex(&a->object.oid));
1138 repo_init_revisions(the_repository, &revs, NULL);
1139 rev_opts.submodule = path;
1140 /* FIXME: can't handle linked worktrees in submodules yet */
1141 revs.single_worktree = path != NULL;
1142 setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1143
1144 /* save all revisions from the above list that contain b */
1145 if (prepare_revision_walk(&revs))
1146 die("revision walk setup failed");
1147 while ((commit = get_revision(&revs)) != NULL) {
1148 struct object *o = &(commit->object);
1149 if (in_merge_bases(b, commit))
1150 add_object_array(o, NULL, &merges);
1151 }
1152 reset_revision_walk();
1153
1154 /* Now we've got all merges that contain a and b. Prune all
1155 * merges that contain another found merge and save them in
1156 * result.
1157 */
1158 for (i = 0; i < merges.nr; i++) {
1159 struct commit *m1 = (struct commit *) merges.objects[i].item;
1160
1161 contains_another = 0;
1162 for (j = 0; j < merges.nr; j++) {
1163 struct commit *m2 = (struct commit *) merges.objects[j].item;
1164 if (i != j && in_merge_bases(m2, m1)) {
1165 contains_another = 1;
1166 break;
1167 }
1168 }
1169
1170 if (!contains_another)
1171 add_object_array(merges.objects[i].item, NULL, result);
1172 }
1173
1174 object_array_clear(&merges);
1175 return result->nr;
1176 }
1177
1178 static void print_commit(struct commit *commit)
1179 {
1180 struct strbuf sb = STRBUF_INIT;
1181 struct pretty_print_context ctx = {0};
1182 ctx.date_mode.type = DATE_NORMAL;
1183 format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1184 fprintf(stderr, "%s\n", sb.buf);
1185 strbuf_release(&sb);
1186 }
1187
1188 static int merge_submodule(struct merge_options *o,
1189 struct object_id *result, const char *path,
1190 const struct object_id *base, const struct object_id *a,
1191 const struct object_id *b)
1192 {
1193 struct commit *commit_base, *commit_a, *commit_b;
1194 int parent_count;
1195 struct object_array merges;
1196
1197 int i;
1198 int search = !o->call_depth;
1199
1200 /* store a in result in case we fail */
1201 oidcpy(result, a);
1202
1203 /* we can not handle deletion conflicts */
1204 if (is_null_oid(base))
1205 return 0;
1206 if (is_null_oid(a))
1207 return 0;
1208 if (is_null_oid(b))
1209 return 0;
1210
1211 if (add_submodule_odb(path)) {
1212 output(o, 1, _("Failed to merge submodule %s (not checked out)"), path);
1213 return 0;
1214 }
1215
1216 if (!(commit_base = lookup_commit_reference(the_repository, base)) ||
1217 !(commit_a = lookup_commit_reference(the_repository, a)) ||
1218 !(commit_b = lookup_commit_reference(the_repository, b))) {
1219 output(o, 1, _("Failed to merge submodule %s (commits not present)"), path);
1220 return 0;
1221 }
1222
1223 /* check whether both changes are forward */
1224 if (!in_merge_bases(commit_base, commit_a) ||
1225 !in_merge_bases(commit_base, commit_b)) {
1226 output(o, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
1227 return 0;
1228 }
1229
1230 /* Case #1: a is contained in b or vice versa */
1231 if (in_merge_bases(commit_a, commit_b)) {
1232 oidcpy(result, b);
1233 if (show(o, 3)) {
1234 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1235 output_commit_title(o, commit_b);
1236 } else if (show(o, 2))
1237 output(o, 2, _("Fast-forwarding submodule %s"), path);
1238 else
1239 ; /* no output */
1240
1241 return 1;
1242 }
1243 if (in_merge_bases(commit_b, commit_a)) {
1244 oidcpy(result, a);
1245 if (show(o, 3)) {
1246 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1247 output_commit_title(o, commit_a);
1248 } else if (show(o, 2))
1249 output(o, 2, _("Fast-forwarding submodule %s"), path);
1250 else
1251 ; /* no output */
1252
1253 return 1;
1254 }
1255
1256 /*
1257 * Case #2: There are one or more merges that contain a and b in
1258 * the submodule. If there is only one, then present it as a
1259 * suggestion to the user, but leave it marked unmerged so the
1260 * user needs to confirm the resolution.
1261 */
1262
1263 /* Skip the search if makes no sense to the calling context. */
1264 if (!search)
1265 return 0;
1266
1267 /* find commit which merges them */
1268 parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1269 switch (parent_count) {
1270 case 0:
1271 output(o, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
1272 break;
1273
1274 case 1:
1275 output(o, 1, _("Failed to merge submodule %s (not fast-forward)"), path);
1276 output(o, 2, _("Found a possible merge resolution for the submodule:\n"));
1277 print_commit((struct commit *) merges.objects[0].item);
1278 output(o, 2, _(
1279 "If this is correct simply add it to the index "
1280 "for example\n"
1281 "by using:\n\n"
1282 " git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1283 "which will accept this suggestion.\n"),
1284 oid_to_hex(&merges.objects[0].item->oid), path);
1285 break;
1286
1287 default:
1288 output(o, 1, _("Failed to merge submodule %s (multiple merges found)"), path);
1289 for (i = 0; i < merges.nr; i++)
1290 print_commit((struct commit *) merges.objects[i].item);
1291 }
1292
1293 object_array_clear(&merges);
1294 return 0;
1295 }
1296
1297 static int merge_mode_and_contents(struct merge_options *o,
1298 const struct diff_filespec *one,
1299 const struct diff_filespec *a,
1300 const struct diff_filespec *b,
1301 const char *filename,
1302 const char *branch1,
1303 const char *branch2,
1304 struct merge_file_info *result)
1305 {
1306 if (o->branch1 != branch1) {
1307 /*
1308 * It's weird getting a reverse merge with HEAD on the bottom
1309 * side of the conflict markers and the other branch on the
1310 * top. Fix that.
1311 */
1312 return merge_mode_and_contents(o, one, b, a,
1313 filename,
1314 branch2, branch1, result);
1315 }
1316
1317 result->merge = 0;
1318 result->clean = 1;
1319
1320 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
1321 result->clean = 0;
1322 if (S_ISREG(a->mode)) {
1323 result->mode = a->mode;
1324 oidcpy(&result->oid, &a->oid);
1325 } else {
1326 result->mode = b->mode;
1327 oidcpy(&result->oid, &b->oid);
1328 }
1329 } else {
1330 if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid))
1331 result->merge = 1;
1332
1333 /*
1334 * Merge modes
1335 */
1336 if (a->mode == b->mode || a->mode == one->mode)
1337 result->mode = b->mode;
1338 else {
1339 result->mode = a->mode;
1340 if (b->mode != one->mode) {
1341 result->clean = 0;
1342 result->merge = 1;
1343 }
1344 }
1345
1346 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid))
1347 oidcpy(&result->oid, &b->oid);
1348 else if (oid_eq(&b->oid, &one->oid))
1349 oidcpy(&result->oid, &a->oid);
1350 else if (S_ISREG(a->mode)) {
1351 mmbuffer_t result_buf;
1352 int ret = 0, merge_status;
1353
1354 merge_status = merge_3way(o, &result_buf, one, a, b,
1355 branch1, branch2);
1356
1357 if ((merge_status < 0) || !result_buf.ptr)
1358 ret = err(o, _("Failed to execute internal merge"));
1359
1360 if (!ret &&
1361 write_object_file(result_buf.ptr, result_buf.size,
1362 blob_type, &result->oid))
1363 ret = err(o, _("Unable to add %s to database"),
1364 a->path);
1365
1366 free(result_buf.ptr);
1367 if (ret)
1368 return ret;
1369 result->clean = (merge_status == 0);
1370 } else if (S_ISGITLINK(a->mode)) {
1371 result->clean = merge_submodule(o, &result->oid,
1372 one->path,
1373 &one->oid,
1374 &a->oid,
1375 &b->oid);
1376 } else if (S_ISLNK(a->mode)) {
1377 switch (o->recursive_variant) {
1378 case MERGE_RECURSIVE_NORMAL:
1379 oidcpy(&result->oid, &a->oid);
1380 if (!oid_eq(&a->oid, &b->oid))
1381 result->clean = 0;
1382 break;
1383 case MERGE_RECURSIVE_OURS:
1384 oidcpy(&result->oid, &a->oid);
1385 break;
1386 case MERGE_RECURSIVE_THEIRS:
1387 oidcpy(&result->oid, &b->oid);
1388 break;
1389 }
1390 } else
1391 BUG("unsupported object type in the tree");
1392 }
1393
1394 if (result->merge)
1395 output(o, 2, _("Auto-merging %s"), filename);
1396
1397 return 0;
1398 }
1399
1400 static int handle_rename_via_dir(struct merge_options *o,
1401 struct diff_filepair *pair,
1402 const char *rename_branch,
1403 const char *other_branch)
1404 {
1405 /*
1406 * Handle file adds that need to be renamed due to directory rename
1407 * detection. This differs from handle_rename_normal, because
1408 * there is no content merge to do; just move the file into the
1409 * desired final location.
1410 */
1411 const struct diff_filespec *dest = pair->two;
1412
1413 if (!o->call_depth && would_lose_untracked(dest->path)) {
1414 char *alt_path = unique_path(o, dest->path, rename_branch);
1415
1416 output(o, 1, _("Error: Refusing to lose untracked file at %s; "
1417 "writing to %s instead."),
1418 dest->path, alt_path);
1419 /*
1420 * Write the file in worktree at alt_path, but not in the
1421 * index. Instead, write to dest->path for the index but
1422 * only at the higher appropriate stage.
1423 */
1424 if (update_file(o, 0, &dest->oid, dest->mode, alt_path))
1425 return -1;
1426 free(alt_path);
1427 return update_stages(o, dest->path, NULL,
1428 rename_branch == o->branch1 ? dest : NULL,
1429 rename_branch == o->branch1 ? NULL : dest);
1430 }
1431
1432 /* Update dest->path both in index and in worktree */
1433 if (update_file(o, 1, &dest->oid, dest->mode, dest->path))
1434 return -1;
1435 return 0;
1436 }
1437
1438 static int handle_change_delete(struct merge_options *o,
1439 const char *path, const char *old_path,
1440 const struct object_id *o_oid, int o_mode,
1441 const struct object_id *changed_oid,
1442 int changed_mode,
1443 const char *change_branch,
1444 const char *delete_branch,
1445 const char *change, const char *change_past)
1446 {
1447 char *alt_path = NULL;
1448 const char *update_path = path;
1449 int ret = 0;
1450
1451 if (dir_in_way(path, !o->call_depth, 0) ||
1452 (!o->call_depth && would_lose_untracked(path))) {
1453 update_path = alt_path = unique_path(o, path, change_branch);
1454 }
1455
1456 if (o->call_depth) {
1457 /*
1458 * We cannot arbitrarily accept either a_sha or b_sha as
1459 * correct; since there is no true "middle point" between
1460 * them, simply reuse the base version for virtual merge base.
1461 */
1462 ret = remove_file_from_cache(path);
1463 if (!ret)
1464 ret = update_file(o, 0, o_oid, o_mode, update_path);
1465 } else {
1466 /*
1467 * Despite the four nearly duplicate messages and argument
1468 * lists below and the ugliness of the nested if-statements,
1469 * having complete messages makes the job easier for
1470 * translators.
1471 *
1472 * The slight variance among the cases is due to the fact
1473 * that:
1474 * 1) directory/file conflicts (in effect if
1475 * !alt_path) could cause us to need to write the
1476 * file to a different path.
1477 * 2) renames (in effect if !old_path) could mean that
1478 * there are two names for the path that the user
1479 * may know the file by.
1480 */
1481 if (!alt_path) {
1482 if (!old_path) {
1483 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1484 "and %s in %s. Version %s of %s left in tree."),
1485 change, path, delete_branch, change_past,
1486 change_branch, change_branch, path);
1487 } else {
1488 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1489 "and %s to %s in %s. Version %s of %s left in tree."),
1490 change, old_path, delete_branch, change_past, path,
1491 change_branch, change_branch, path);
1492 }
1493 } else {
1494 if (!old_path) {
1495 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1496 "and %s in %s. Version %s of %s left in tree at %s."),
1497 change, path, delete_branch, change_past,
1498 change_branch, change_branch, path, alt_path);
1499 } else {
1500 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1501 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1502 change, old_path, delete_branch, change_past, path,
1503 change_branch, change_branch, path, alt_path);
1504 }
1505 }
1506 /*
1507 * No need to call update_file() on path when change_branch ==
1508 * o->branch1 && !alt_path, since that would needlessly touch
1509 * path. We could call update_file_flags() with update_cache=0
1510 * and update_wd=0, but that's a no-op.
1511 */
1512 if (change_branch != o->branch1 || alt_path)
1513 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1514 }
1515 free(alt_path);
1516
1517 return ret;
1518 }
1519
1520 static int handle_rename_delete(struct merge_options *o,
1521 struct diff_filepair *pair,
1522 const char *rename_branch,
1523 const char *delete_branch)
1524 {
1525 const struct diff_filespec *orig = pair->one;
1526 const struct diff_filespec *dest = pair->two;
1527
1528 if (handle_change_delete(o,
1529 o->call_depth ? orig->path : dest->path,
1530 o->call_depth ? NULL : orig->path,
1531 &orig->oid, orig->mode,
1532 &dest->oid, dest->mode,
1533 rename_branch, delete_branch,
1534 _("rename"), _("renamed")))
1535 return -1;
1536
1537 if (o->call_depth)
1538 return remove_file_from_cache(dest->path);
1539 else
1540 return update_stages(o, dest->path, NULL,
1541 rename_branch == o->branch1 ? dest : NULL,
1542 rename_branch == o->branch1 ? NULL : dest);
1543 }
1544
1545 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1546 struct stage_data *entry,
1547 int stage)
1548 {
1549 struct object_id *oid = &entry->stages[stage].oid;
1550 unsigned mode = entry->stages[stage].mode;
1551 if (mode == 0 || is_null_oid(oid))
1552 return NULL;
1553 oidcpy(&target->oid, oid);
1554 target->mode = mode;
1555 return target;
1556 }
1557
1558 static int handle_file(struct merge_options *o,
1559 struct diff_filespec *rename,
1560 int stage,
1561 struct rename_conflict_info *ci)
1562 {
1563 char *dst_name = rename->path;
1564 struct stage_data *dst_entry;
1565 const char *cur_branch, *other_branch;
1566 struct diff_filespec other;
1567 struct diff_filespec *add;
1568 int ret;
1569
1570 if (stage == 2) {
1571 dst_entry = ci->dst_entry1;
1572 cur_branch = ci->branch1;
1573 other_branch = ci->branch2;
1574 } else {
1575 dst_entry = ci->dst_entry2;
1576 cur_branch = ci->branch2;
1577 other_branch = ci->branch1;
1578 }
1579
1580 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1581 if (add) {
1582 int ren_src_was_dirty = was_dirty(o, rename->path);
1583 char *add_name = unique_path(o, rename->path, other_branch);
1584 if (update_file(o, 0, &add->oid, add->mode, add_name))
1585 return -1;
1586
1587 if (ren_src_was_dirty) {
1588 output(o, 1, _("Refusing to lose dirty file at %s"),
1589 rename->path);
1590 }
1591 /*
1592 * Because the double negatives somehow keep confusing me...
1593 * 1) update_wd iff !ren_src_was_dirty.
1594 * 2) no_wd iff !update_wd
1595 * 3) so, no_wd == !!ren_src_was_dirty == ren_src_was_dirty
1596 */
1597 remove_file(o, 0, rename->path, ren_src_was_dirty);
1598 dst_name = unique_path(o, rename->path, cur_branch);
1599 } else {
1600 if (dir_in_way(rename->path, !o->call_depth, 0)) {
1601 dst_name = unique_path(o, rename->path, cur_branch);
1602 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1603 rename->path, other_branch, dst_name);
1604 } else if (!o->call_depth &&
1605 would_lose_untracked(rename->path)) {
1606 dst_name = unique_path(o, rename->path, cur_branch);
1607 output(o, 1, _("Refusing to lose untracked file at %s; "
1608 "adding as %s instead"),
1609 rename->path, dst_name);
1610 }
1611 }
1612 if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name)))
1613 ; /* fall through, do allow dst_name to be released */
1614 else if (stage == 2)
1615 ret = update_stages(o, rename->path, NULL, rename, add);
1616 else
1617 ret = update_stages(o, rename->path, NULL, add, rename);
1618
1619 if (dst_name != rename->path)
1620 free(dst_name);
1621
1622 return ret;
1623 }
1624
1625 static int handle_rename_rename_1to2(struct merge_options *o,
1626 struct rename_conflict_info *ci)
1627 {
1628 /* One file was renamed in both branches, but to different names. */
1629 struct diff_filespec *one = ci->pair1->one;
1630 struct diff_filespec *a = ci->pair1->two;
1631 struct diff_filespec *b = ci->pair2->two;
1632
1633 output(o, 1, _("CONFLICT (rename/rename): "
1634 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1635 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1636 one->path, a->path, ci->branch1,
1637 one->path, b->path, ci->branch2,
1638 o->call_depth ? _(" (left unresolved)") : "");
1639 if (o->call_depth) {
1640 struct merge_file_info mfi;
1641 struct diff_filespec other;
1642 struct diff_filespec *add;
1643 if (merge_mode_and_contents(o, one, a, b, one->path,
1644 ci->branch1, ci->branch2, &mfi))
1645 return -1;
1646
1647 /*
1648 * FIXME: For rename/add-source conflicts (if we could detect
1649 * such), this is wrong. We should instead find a unique
1650 * pathname and then either rename the add-source file to that
1651 * unique path, or use that unique path instead of src here.
1652 */
1653 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1654 return -1;
1655
1656 /*
1657 * Above, we put the merged content at the merge-base's
1658 * path. Now we usually need to delete both a->path and
1659 * b->path. However, the rename on each side of the merge
1660 * could also be involved in a rename/add conflict. In
1661 * such cases, we should keep the added file around,
1662 * resolving the conflict at that path in its favor.
1663 */
1664 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1665 if (add) {
1666 if (update_file(o, 0, &add->oid, add->mode, a->path))
1667 return -1;
1668 }
1669 else
1670 remove_file_from_cache(a->path);
1671 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1672 if (add) {
1673 if (update_file(o, 0, &add->oid, add->mode, b->path))
1674 return -1;
1675 }
1676 else
1677 remove_file_from_cache(b->path);
1678 } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci))
1679 return -1;
1680
1681 return 0;
1682 }
1683
1684 static int handle_rename_rename_2to1(struct merge_options *o,
1685 struct rename_conflict_info *ci)
1686 {
1687 /* Two files, a & b, were renamed to the same thing, c. */
1688 struct diff_filespec *a = ci->pair1->one;
1689 struct diff_filespec *b = ci->pair2->one;
1690 struct diff_filespec *c1 = ci->pair1->two;
1691 struct diff_filespec *c2 = ci->pair2->two;
1692 char *path = c1->path; /* == c2->path */
1693 char *path_side_1_desc;
1694 char *path_side_2_desc;
1695 struct merge_file_info mfi_c1;
1696 struct merge_file_info mfi_c2;
1697 int ret;
1698
1699 output(o, 1, _("CONFLICT (rename/rename): "
1700 "Rename %s->%s in %s. "
1701 "Rename %s->%s in %s"),
1702 a->path, c1->path, ci->branch1,
1703 b->path, c2->path, ci->branch2);
1704
1705 remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path));
1706 remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path));
1707
1708 path_side_1_desc = xstrfmt("version of %s from %s", path, a->path);
1709 path_side_2_desc = xstrfmt("version of %s from %s", path, b->path);
1710 if (merge_mode_and_contents(o, a, c1, &ci->ren1_other, path_side_1_desc,
1711 o->branch1, o->branch2, &mfi_c1) ||
1712 merge_mode_and_contents(o, b, &ci->ren2_other, c2, path_side_2_desc,
1713 o->branch1, o->branch2, &mfi_c2))
1714 return -1;
1715 free(path_side_1_desc);
1716 free(path_side_2_desc);
1717
1718 if (o->call_depth) {
1719 /*
1720 * If mfi_c1.clean && mfi_c2.clean, then it might make
1721 * sense to do a two-way merge of those results. But, I
1722 * think in all cases, it makes sense to have the virtual
1723 * merge base just undo the renames; they can be detected
1724 * again later for the non-recursive merge.
1725 */
1726 remove_file(o, 0, path, 0);
1727 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path);
1728 if (!ret)
1729 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1730 b->path);
1731 } else {
1732 char *new_path1 = unique_path(o, path, ci->branch1);
1733 char *new_path2 = unique_path(o, path, ci->branch2);
1734 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1735 a->path, new_path1, b->path, new_path2);
1736 if (was_dirty(o, path))
1737 output(o, 1, _("Refusing to lose dirty file at %s"),
1738 path);
1739 else if (would_lose_untracked(path))
1740 /*
1741 * Only way we get here is if both renames were from
1742 * a directory rename AND user had an untracked file
1743 * at the location where both files end up after the
1744 * two directory renames. See testcase 10d of t6043.
1745 */
1746 output(o, 1, _("Refusing to lose untracked file at "
1747 "%s, even though it's in the way."),
1748 path);
1749 else
1750 remove_file(o, 0, path, 0);
1751 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1);
1752 if (!ret)
1753 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1754 new_path2);
1755 /*
1756 * unpack_trees() actually populates the index for us for
1757 * "normal" rename/rename(2to1) situtations so that the
1758 * correct entries are at the higher stages, which would
1759 * make the call below to update_stages_for_stage_data
1760 * unnecessary. However, if either of the renames came
1761 * from a directory rename, then unpack_trees() will not
1762 * have gotten the right data loaded into the index, so we
1763 * need to do so now. (While it'd be tempting to move this
1764 * call to update_stages_for_stage_data() to
1765 * apply_directory_rename_modifications(), that would break
1766 * our intermediate calls to would_lose_untracked() since
1767 * those rely on the current in-memory index. See also the
1768 * big "NOTE" in update_stages()).
1769 */
1770 if (update_stages_for_stage_data(o, path, ci->dst_entry1))
1771 ret = -1;
1772
1773 free(new_path2);
1774 free(new_path1);
1775 }
1776
1777 return ret;
1778 }
1779
1780 /*
1781 * Get the diff_filepairs changed between o_tree and tree.
1782 */
1783 static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
1784 struct tree *o_tree,
1785 struct tree *tree)
1786 {
1787 struct diff_queue_struct *ret;
1788 struct diff_options opts;
1789
1790 repo_diff_setup(the_repository, &opts);
1791 opts.flags.recursive = 1;
1792 opts.flags.rename_empty = 0;
1793 opts.detect_rename = merge_detect_rename(o);
1794 /*
1795 * We do not have logic to handle the detection of copies. In
1796 * fact, it may not even make sense to add such logic: would we
1797 * really want a change to a base file to be propagated through
1798 * multiple other files by a merge?
1799 */
1800 if (opts.detect_rename > DIFF_DETECT_RENAME)
1801 opts.detect_rename = DIFF_DETECT_RENAME;
1802 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
1803 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
1804 1000;
1805 opts.rename_score = o->rename_score;
1806 opts.show_rename_progress = o->show_rename_progress;
1807 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1808 diff_setup_done(&opts);
1809 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1810 diffcore_std(&opts);
1811 if (opts.needed_rename_limit > o->needed_rename_limit)
1812 o->needed_rename_limit = opts.needed_rename_limit;
1813
1814 ret = xmalloc(sizeof(*ret));
1815 *ret = diff_queued_diff;
1816
1817 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1818 diff_queued_diff.nr = 0;
1819 diff_queued_diff.queue = NULL;
1820 diff_flush(&opts);
1821 return ret;
1822 }
1823
1824 static int tree_has_path(struct tree *tree, const char *path)
1825 {
1826 struct object_id hashy;
1827 unsigned int mode_o;
1828
1829 return !get_tree_entry(&tree->object.oid, path,
1830 &hashy, &mode_o);
1831 }
1832
1833 /*
1834 * Return a new string that replaces the beginning portion (which matches
1835 * entry->dir), with entry->new_dir. In perl-speak:
1836 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1837 * NOTE:
1838 * Caller must ensure that old_path starts with entry->dir + '/'.
1839 */
1840 static char *apply_dir_rename(struct dir_rename_entry *entry,
1841 const char *old_path)
1842 {
1843 struct strbuf new_path = STRBUF_INIT;
1844 int oldlen, newlen;
1845
1846 if (entry->non_unique_new_dir)
1847 return NULL;
1848
1849 oldlen = strlen(entry->dir);
1850 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1851 strbuf_grow(&new_path, newlen);
1852 strbuf_addbuf(&new_path, &entry->new_dir);
1853 strbuf_addstr(&new_path, &old_path[oldlen]);
1854
1855 return strbuf_detach(&new_path, NULL);
1856 }
1857
1858 static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1859 char **old_dir, char **new_dir)
1860 {
1861 char *end_of_old, *end_of_new;
1862 int old_len, new_len;
1863
1864 *old_dir = NULL;
1865 *new_dir = NULL;
1866
1867 /*
1868 * For
1869 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1870 * the "e/foo.c" part is the same, we just want to know that
1871 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1872 * so, for this example, this function returns "a/b/c/d" in
1873 * *old_dir and "a/b/some/thing/else" in *new_dir.
1874 *
1875 * Also, if the basename of the file changed, we don't care. We
1876 * want to know which portion of the directory, if any, changed.
1877 */
1878 end_of_old = strrchr(old_path, '/');
1879 end_of_new = strrchr(new_path, '/');
1880
1881 if (end_of_old == NULL || end_of_new == NULL)
1882 return;
1883 while (*--end_of_new == *--end_of_old &&
1884 end_of_old != old_path &&
1885 end_of_new != new_path)
1886 ; /* Do nothing; all in the while loop */
1887 /*
1888 * We've found the first non-matching character in the directory
1889 * paths. That means the current directory we were comparing
1890 * represents the rename. Move end_of_old and end_of_new back
1891 * to the full directory name.
1892 */
1893 if (*end_of_old == '/')
1894 end_of_old++;
1895 if (*end_of_old != '/')
1896 end_of_new++;
1897 end_of_old = strchr(end_of_old, '/');
1898 end_of_new = strchr(end_of_new, '/');
1899
1900 /*
1901 * It may have been the case that old_path and new_path were the same
1902 * directory all along. Don't claim a rename if they're the same.
1903 */
1904 old_len = end_of_old - old_path;
1905 new_len = end_of_new - new_path;
1906
1907 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
1908 *old_dir = xstrndup(old_path, old_len);
1909 *new_dir = xstrndup(new_path, new_len);
1910 }
1911 }
1912
1913 static void remove_hashmap_entries(struct hashmap *dir_renames,
1914 struct string_list *items_to_remove)
1915 {
1916 int i;
1917 struct dir_rename_entry *entry;
1918
1919 for (i = 0; i < items_to_remove->nr; i++) {
1920 entry = items_to_remove->items[i].util;
1921 hashmap_remove(dir_renames, entry, NULL);
1922 }
1923 string_list_clear(items_to_remove, 0);
1924 }
1925
1926 /*
1927 * See if there is a directory rename for path, and if there are any file
1928 * level conflicts for the renamed location. If there is a rename and
1929 * there are no conflicts, return the new name. Otherwise, return NULL.
1930 */
1931 static char *handle_path_level_conflicts(struct merge_options *o,
1932 const char *path,
1933 struct dir_rename_entry *entry,
1934 struct hashmap *collisions,
1935 struct tree *tree)
1936 {
1937 char *new_path = NULL;
1938 struct collision_entry *collision_ent;
1939 int clean = 1;
1940 struct strbuf collision_paths = STRBUF_INIT;
1941
1942 /*
1943 * entry has the mapping of old directory name to new directory name
1944 * that we want to apply to path.
1945 */
1946 new_path = apply_dir_rename(entry, path);
1947
1948 if (!new_path) {
1949 /* This should only happen when entry->non_unique_new_dir set */
1950 if (!entry->non_unique_new_dir)
1951 BUG("entry->non_unqiue_dir not set and !new_path");
1952 output(o, 1, _("CONFLICT (directory rename split): "
1953 "Unclear where to place %s because directory "
1954 "%s was renamed to multiple other directories, "
1955 "with no destination getting a majority of the "
1956 "files."),
1957 path, entry->dir);
1958 clean = 0;
1959 return NULL;
1960 }
1961
1962 /*
1963 * The caller needs to have ensured that it has pre-populated
1964 * collisions with all paths that map to new_path. Do a quick check
1965 * to ensure that's the case.
1966 */
1967 collision_ent = collision_find_entry(collisions, new_path);
1968 if (collision_ent == NULL)
1969 BUG("collision_ent is NULL");
1970
1971 /*
1972 * Check for one-sided add/add/.../add conflicts, i.e.
1973 * where implicit renames from the other side doing
1974 * directory rename(s) can affect this side of history
1975 * to put multiple paths into the same location. Warn
1976 * and bail on directory renames for such paths.
1977 */
1978 if (collision_ent->reported_already) {
1979 clean = 0;
1980 } else if (tree_has_path(tree, new_path)) {
1981 collision_ent->reported_already = 1;
1982 strbuf_add_separated_string_list(&collision_paths, ", ",
1983 &collision_ent->source_files);
1984 output(o, 1, _("CONFLICT (implicit dir rename): Existing "
1985 "file/dir at %s in the way of implicit "
1986 "directory rename(s) putting the following "
1987 "path(s) there: %s."),
1988 new_path, collision_paths.buf);
1989 clean = 0;
1990 } else if (collision_ent->source_files.nr > 1) {
1991 collision_ent->reported_already = 1;
1992 strbuf_add_separated_string_list(&collision_paths, ", ",
1993 &collision_ent->source_files);
1994 output(o, 1, _("CONFLICT (implicit dir rename): Cannot map "
1995 "more than one path to %s; implicit directory "
1996 "renames tried to put these paths there: %s"),
1997 new_path, collision_paths.buf);
1998 clean = 0;
1999 }
2000
2001 /* Free memory we no longer need */
2002 strbuf_release(&collision_paths);
2003 if (!clean && new_path) {
2004 free(new_path);
2005 return NULL;
2006 }
2007
2008 return new_path;
2009 }
2010
2011 /*
2012 * There are a couple things we want to do at the directory level:
2013 * 1. Check for both sides renaming to the same thing, in order to avoid
2014 * implicit renaming of files that should be left in place. (See
2015 * testcase 6b in t6043 for details.)
2016 * 2. Prune directory renames if there are still files left in the
2017 * the original directory. These represent a partial directory rename,
2018 * i.e. a rename where only some of the files within the directory
2019 * were renamed elsewhere. (Technically, this could be done earlier
2020 * in get_directory_renames(), except that would prevent us from
2021 * doing the previous check and thus failing testcase 6b.)
2022 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
2023 * In the future, we could potentially record this info as well and
2024 * omit reporting rename/rename(1to2) conflicts for each path within
2025 * the affected directories, thus cleaning up the merge output.
2026 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
2027 * directory level, because merging directories is fine. If it
2028 * causes conflicts for files within those merged directories, then
2029 * that should be detected at the individual path level.
2030 */
2031 static void handle_directory_level_conflicts(struct merge_options *o,
2032 struct hashmap *dir_re_head,
2033 struct tree *head,
2034 struct hashmap *dir_re_merge,
2035 struct tree *merge)
2036 {
2037 struct hashmap_iter iter;
2038 struct dir_rename_entry *head_ent;
2039 struct dir_rename_entry *merge_ent;
2040
2041 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
2042 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
2043
2044 hashmap_iter_init(dir_re_head, &iter);
2045 while ((head_ent = hashmap_iter_next(&iter))) {
2046 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
2047 if (merge_ent &&
2048 !head_ent->non_unique_new_dir &&
2049 !merge_ent->non_unique_new_dir &&
2050 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
2051 /* 1. Renamed identically; remove it from both sides */
2052 string_list_append(&remove_from_head,
2053 head_ent->dir)->util = head_ent;
2054 strbuf_release(&head_ent->new_dir);
2055 string_list_append(&remove_from_merge,
2056 merge_ent->dir)->util = merge_ent;
2057 strbuf_release(&merge_ent->new_dir);
2058 } else if (tree_has_path(head, head_ent->dir)) {
2059 /* 2. This wasn't a directory rename after all */
2060 string_list_append(&remove_from_head,
2061 head_ent->dir)->util = head_ent;
2062 strbuf_release(&head_ent->new_dir);
2063 }
2064 }
2065
2066 remove_hashmap_entries(dir_re_head, &remove_from_head);
2067 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2068
2069 hashmap_iter_init(dir_re_merge, &iter);
2070 while ((merge_ent = hashmap_iter_next(&iter))) {
2071 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
2072 if (tree_has_path(merge, merge_ent->dir)) {
2073 /* 2. This wasn't a directory rename after all */
2074 string_list_append(&remove_from_merge,
2075 merge_ent->dir)->util = merge_ent;
2076 } else if (head_ent &&
2077 !head_ent->non_unique_new_dir &&
2078 !merge_ent->non_unique_new_dir) {
2079 /* 3. rename/rename(1to2) */
2080 /*
2081 * We can assume it's not rename/rename(1to1) because
2082 * that was case (1), already checked above. So we
2083 * know that head_ent->new_dir and merge_ent->new_dir
2084 * are different strings.
2085 */
2086 output(o, 1, _("CONFLICT (rename/rename): "
2087 "Rename directory %s->%s in %s. "
2088 "Rename directory %s->%s in %s"),
2089 head_ent->dir, head_ent->new_dir.buf, o->branch1,
2090 head_ent->dir, merge_ent->new_dir.buf, o->branch2);
2091 string_list_append(&remove_from_head,
2092 head_ent->dir)->util = head_ent;
2093 strbuf_release(&head_ent->new_dir);
2094 string_list_append(&remove_from_merge,
2095 merge_ent->dir)->util = merge_ent;
2096 strbuf_release(&merge_ent->new_dir);
2097 }
2098 }
2099
2100 remove_hashmap_entries(dir_re_head, &remove_from_head);
2101 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2102 }
2103
2104 static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
2105 struct tree *tree)
2106 {
2107 struct hashmap *dir_renames;
2108 struct hashmap_iter iter;
2109 struct dir_rename_entry *entry;
2110 int i;
2111
2112 /*
2113 * Typically, we think of a directory rename as all files from a
2114 * certain directory being moved to a target directory. However,
2115 * what if someone first moved two files from the original
2116 * directory in one commit, and then renamed the directory
2117 * somewhere else in a later commit? At merge time, we just know
2118 * that files from the original directory went to two different
2119 * places, and that the bulk of them ended up in the same place.
2120 * We want each directory rename to represent where the bulk of the
2121 * files from that directory end up; this function exists to find
2122 * where the bulk of the files went.
2123 *
2124 * The first loop below simply iterates through the list of file
2125 * renames, finding out how often each directory rename pair
2126 * possibility occurs.
2127 */
2128 dir_renames = xmalloc(sizeof(*dir_renames));
2129 dir_rename_init(dir_renames);
2130 for (i = 0; i < pairs->nr; ++i) {
2131 struct string_list_item *item;
2132 int *count;
2133 struct diff_filepair *pair = pairs->queue[i];
2134 char *old_dir, *new_dir;
2135
2136 /* File not part of directory rename if it wasn't renamed */
2137 if (pair->status != 'R')
2138 continue;
2139
2140 get_renamed_dir_portion(pair->one->path, pair->two->path,
2141 &old_dir, &new_dir);
2142 if (!old_dir)
2143 /* Directory didn't change at all; ignore this one. */
2144 continue;
2145
2146 entry = dir_rename_find_entry(dir_renames, old_dir);
2147 if (!entry) {
2148 entry = xmalloc(sizeof(*entry));
2149 dir_rename_entry_init(entry, old_dir);
2150 hashmap_put(dir_renames, entry);
2151 } else {
2152 free(old_dir);
2153 }
2154 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
2155 if (!item) {
2156 item = string_list_insert(&entry->possible_new_dirs,
2157 new_dir);
2158 item->util = xcalloc(1, sizeof(int));
2159 } else {
2160 free(new_dir);
2161 }
2162 count = item->util;
2163 *count += 1;
2164 }
2165
2166 /*
2167 * For each directory with files moved out of it, we find out which
2168 * target directory received the most files so we can declare it to
2169 * be the "winning" target location for the directory rename. This
2170 * winner gets recorded in new_dir. If there is no winner
2171 * (multiple target directories received the same number of files),
2172 * we set non_unique_new_dir. Once we've determined the winner (or
2173 * that there is no winner), we no longer need possible_new_dirs.
2174 */
2175 hashmap_iter_init(dir_renames, &iter);
2176 while ((entry = hashmap_iter_next(&iter))) {
2177 int max = 0;
2178 int bad_max = 0;
2179 char *best = NULL;
2180
2181 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
2182 int *count = entry->possible_new_dirs.items[i].util;
2183
2184 if (*count == max)
2185 bad_max = max;
2186 else if (*count > max) {
2187 max = *count;
2188 best = entry->possible_new_dirs.items[i].string;
2189 }
2190 }
2191 if (bad_max == max)
2192 entry->non_unique_new_dir = 1;
2193 else {
2194 assert(entry->new_dir.len == 0);
2195 strbuf_addstr(&entry->new_dir, best);
2196 }
2197 /*
2198 * The relevant directory sub-portion of the original full
2199 * filepaths were xstrndup'ed before inserting into
2200 * possible_new_dirs, and instead of manually iterating the
2201 * list and free'ing each, just lie and tell
2202 * possible_new_dirs that it did the strdup'ing so that it
2203 * will free them for us.
2204 */
2205 entry->possible_new_dirs.strdup_strings = 1;
2206 string_list_clear(&entry->possible_new_dirs, 1);
2207 }
2208
2209 return dir_renames;
2210 }
2211
2212 static struct dir_rename_entry *check_dir_renamed(const char *path,
2213 struct hashmap *dir_renames)
2214 {
2215 char *temp = xstrdup(path);
2216 char *end;
2217 struct dir_rename_entry *entry = NULL;
2218
2219 while ((end = strrchr(temp, '/'))) {
2220 *end = '\0';
2221 entry = dir_rename_find_entry(dir_renames, temp);
2222 if (entry)
2223 break;
2224 }
2225 free(temp);
2226 return entry;
2227 }
2228
2229 static void compute_collisions(struct hashmap *collisions,
2230 struct hashmap *dir_renames,
2231 struct diff_queue_struct *pairs)
2232 {
2233 int i;
2234
2235 /*
2236 * Multiple files can be mapped to the same path due to directory
2237 * renames done by the other side of history. Since that other
2238 * side of history could have merged multiple directories into one,
2239 * if our side of history added the same file basename to each of
2240 * those directories, then all N of them would get implicitly
2241 * renamed by the directory rename detection into the same path,
2242 * and we'd get an add/add/.../add conflict, and all those adds
2243 * from *this* side of history. This is not representable in the
2244 * index, and users aren't going to easily be able to make sense of
2245 * it. So we need to provide a good warning about what's
2246 * happening, and fall back to no-directory-rename detection
2247 * behavior for those paths.
2248 *
2249 * See testcases 9e and all of section 5 from t6043 for examples.
2250 */
2251 collision_init(collisions);
2252
2253 for (i = 0; i < pairs->nr; ++i) {
2254 struct dir_rename_entry *dir_rename_ent;
2255 struct collision_entry *collision_ent;
2256 char *new_path;
2257 struct diff_filepair *pair = pairs->queue[i];
2258
2259 if (pair->status != 'A' && pair->status != 'R')
2260 continue;
2261 dir_rename_ent = check_dir_renamed(pair->two->path,
2262 dir_renames);
2263 if (!dir_rename_ent)
2264 continue;
2265
2266 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
2267 if (!new_path)
2268 /*
2269 * dir_rename_ent->non_unique_new_path is true, which
2270 * means there is no directory rename for us to use,
2271 * which means it won't cause us any additional
2272 * collisions.
2273 */
2274 continue;
2275 collision_ent = collision_find_entry(collisions, new_path);
2276 if (!collision_ent) {
2277 collision_ent = xcalloc(1,
2278 sizeof(struct collision_entry));
2279 hashmap_entry_init(collision_ent, strhash(new_path));
2280 hashmap_put(collisions, collision_ent);
2281 collision_ent->target_file = new_path;
2282 } else {
2283 free(new_path);
2284 }
2285 string_list_insert(&collision_ent->source_files,
2286 pair->two->path);
2287 }
2288 }
2289
2290 static char *check_for_directory_rename(struct merge_options *o,
2291 const char *path,
2292 struct tree *tree,
2293 struct hashmap *dir_renames,
2294 struct hashmap *dir_rename_exclusions,
2295 struct hashmap *collisions,
2296 int *clean_merge)
2297 {
2298 char *new_path = NULL;
2299 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
2300 struct dir_rename_entry *oentry = NULL;
2301
2302 if (!entry)
2303 return new_path;
2304
2305 /*
2306 * This next part is a little weird. We do not want to do an
2307 * implicit rename into a directory we renamed on our side, because
2308 * that will result in a spurious rename/rename(1to2) conflict. An
2309 * example:
2310 * Base commit: dumbdir/afile, otherdir/bfile
2311 * Side 1: smrtdir/afile, otherdir/bfile
2312 * Side 2: dumbdir/afile, dumbdir/bfile
2313 * Here, while working on Side 1, we could notice that otherdir was
2314 * renamed/merged to dumbdir, and change the diff_filepair for
2315 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
2316 * 2 will notice the rename from dumbdir to smrtdir, and do the
2317 * transitive rename to move it from dumbdir/bfile to
2318 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
2319 * smrtdir, a rename/rename(1to2) conflict. We really just want
2320 * the file to end up in smrtdir. And the way to achieve that is
2321 * to not let Side1 do the rename to dumbdir, since we know that is
2322 * the source of one of our directory renames.
2323 *
2324 * That's why oentry and dir_rename_exclusions is here.
2325 *
2326 * As it turns out, this also prevents N-way transient rename
2327 * confusion; See testcases 9c and 9d of t6043.
2328 */
2329 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
2330 if (oentry) {
2331 output(o, 1, _("WARNING: Avoiding applying %s -> %s rename "
2332 "to %s, because %s itself was renamed."),
2333 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
2334 } else {
2335 new_path = handle_path_level_conflicts(o, path, entry,
2336 collisions, tree);
2337 *clean_merge &= (new_path != NULL);
2338 }
2339
2340 return new_path;
2341 }
2342
2343 static void apply_directory_rename_modifications(struct merge_options *o,
2344 struct diff_filepair *pair,
2345 char *new_path,
2346 struct rename *re,
2347 struct tree *tree,
2348 struct tree *o_tree,
2349 struct tree *a_tree,
2350 struct tree *b_tree,
2351 struct string_list *entries,
2352 int *clean)
2353 {
2354 struct string_list_item *item;
2355 int stage = (tree == a_tree ? 2 : 3);
2356 int update_wd;
2357
2358 /*
2359 * In all cases where we can do directory rename detection,
2360 * unpack_trees() will have read pair->two->path into the
2361 * index and the working copy. We need to remove it so that
2362 * we can instead place it at new_path. It is guaranteed to
2363 * not be untracked (unpack_trees() would have errored out
2364 * saying the file would have been overwritten), but it might
2365 * be dirty, though.
2366 */
2367 update_wd = !was_dirty(o, pair->two->path);
2368 if (!update_wd)
2369 output(o, 1, _("Refusing to lose dirty file at %s"),
2370 pair->two->path);
2371 remove_file(o, 1, pair->two->path, !update_wd);
2372
2373 /* Find or create a new re->dst_entry */
2374 item = string_list_lookup(entries, new_path);
2375 if (item) {
2376 /*
2377 * Since we're renaming on this side of history, and it's
2378 * due to a directory rename on the other side of history
2379 * (which we only allow when the directory in question no
2380 * longer exists on the other side of history), the
2381 * original entry for re->dst_entry is no longer
2382 * necessary...
2383 */
2384 re->dst_entry->processed = 1;
2385
2386 /*
2387 * ...because we'll be using this new one.
2388 */
2389 re->dst_entry = item->util;
2390 } else {
2391 /*
2392 * re->dst_entry is for the before-dir-rename path, and we
2393 * need it to hold information for the after-dir-rename
2394 * path. Before creating a new entry, we need to mark the
2395 * old one as unnecessary (...unless it is shared by
2396 * src_entry, i.e. this didn't use to be a rename, in which
2397 * case we can just allow the normal processing to happen
2398 * for it).
2399 */
2400 if (pair->status == 'R')
2401 re->dst_entry->processed = 1;
2402
2403 re->dst_entry = insert_stage_data(new_path,
2404 o_tree, a_tree, b_tree,
2405 entries);
2406 item = string_list_insert(entries, new_path);
2407 item->util = re->dst_entry;
2408 }
2409
2410 /*
2411 * Update the stage_data with the information about the path we are
2412 * moving into place. That slot will be empty and available for us
2413 * to write to because of the collision checks in
2414 * handle_path_level_conflicts(). In other words,
2415 * re->dst_entry->stages[stage].oid will be the null_oid, so it's
2416 * open for us to write to.
2417 *
2418 * It may be tempting to actually update the index at this point as
2419 * well, using update_stages_for_stage_data(), but as per the big
2420 * "NOTE" in update_stages(), doing so will modify the current
2421 * in-memory index which will break calls to would_lose_untracked()
2422 * that we need to make. Instead, we need to just make sure that
2423 * the various handle_rename_*() functions update the index
2424 * explicitly rather than relying on unpack_trees() to have done it.
2425 */
2426 get_tree_entry(&tree->object.oid,
2427 pair->two->path,
2428 &re->dst_entry->stages[stage].oid,
2429 &re->dst_entry->stages[stage].mode);
2430
2431 /* Update pair status */
2432 if (pair->status == 'A') {
2433 /*
2434 * Recording rename information for this add makes it look
2435 * like a rename/delete conflict. Make sure we can
2436 * correctly handle this as an add that was moved to a new
2437 * directory instead of reporting a rename/delete conflict.
2438 */
2439 re->add_turned_into_rename = 1;
2440 }
2441 /*
2442 * We don't actually look at pair->status again, but it seems
2443 * pedagogically correct to adjust it.
2444 */
2445 pair->status = 'R';
2446
2447 /*
2448 * Finally, record the new location.
2449 */
2450 pair->two->path = new_path;
2451 }
2452
2453 /*
2454 * Get information of all renames which occurred in 'pairs', making use of
2455 * any implicit directory renames inferred from the other side of history.
2456 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
2457 * to be able to associate the correct cache entries with the rename
2458 * information; tree is always equal to either a_tree or b_tree.
2459 */
2460 static struct string_list *get_renames(struct merge_options *o,
2461 struct diff_queue_struct *pairs,
2462 struct hashmap *dir_renames,
2463 struct hashmap *dir_rename_exclusions,
2464 struct tree *tree,
2465 struct tree *o_tree,
2466 struct tree *a_tree,
2467 struct tree *b_tree,
2468 struct string_list *entries,
2469 int *clean_merge)
2470 {
2471 int i;
2472 struct hashmap collisions;
2473 struct hashmap_iter iter;
2474 struct collision_entry *e;
2475 struct string_list *renames;
2476
2477 compute_collisions(&collisions, dir_renames, pairs);
2478 renames = xcalloc(1, sizeof(struct string_list));
2479
2480 for (i = 0; i < pairs->nr; ++i) {
2481 struct string_list_item *item;
2482 struct rename *re;
2483 struct diff_filepair *pair = pairs->queue[i];
2484 char *new_path; /* non-NULL only with directory renames */
2485
2486 if (pair->status != 'A' && pair->status != 'R') {
2487 diff_free_filepair(pair);
2488 continue;
2489 }
2490 new_path = check_for_directory_rename(o, pair->two->path, tree,
2491 dir_renames,
2492 dir_rename_exclusions,
2493 &collisions,
2494 clean_merge);
2495 if (pair->status != 'R' && !new_path) {
2496 diff_free_filepair(pair);
2497 continue;
2498 }
2499
2500 re = xmalloc(sizeof(*re));
2501 re->processed = 0;
2502 re->add_turned_into_rename = 0;
2503 re->pair = pair;
2504 item = string_list_lookup(entries, re->pair->one->path);
2505 if (!item)
2506 re->src_entry = insert_stage_data(re->pair->one->path,
2507 o_tree, a_tree, b_tree, entries);
2508 else
2509 re->src_entry = item->util;
2510
2511 item = string_list_lookup(entries, re->pair->two->path);
2512 if (!item)
2513 re->dst_entry = insert_stage_data(re->pair->two->path,
2514 o_tree, a_tree, b_tree, entries);
2515 else
2516 re->dst_entry = item->util;
2517 item = string_list_insert(renames, pair->one->path);
2518 item->util = re;
2519 if (new_path)
2520 apply_directory_rename_modifications(o, pair, new_path,
2521 re, tree, o_tree,
2522 a_tree, b_tree,
2523 entries,
2524 clean_merge);
2525 }
2526
2527 hashmap_iter_init(&collisions, &iter);
2528 while ((e = hashmap_iter_next(&iter))) {
2529 free(e->target_file);
2530 string_list_clear(&e->source_files, 0);
2531 }
2532 hashmap_free(&collisions, 1);
2533 return renames;
2534 }
2535
2536 static int process_renames(struct merge_options *o,
2537 struct string_list *a_renames,
2538 struct string_list *b_renames)
2539 {
2540 int clean_merge = 1, i, j;
2541 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2542 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2543 const struct rename *sre;
2544
2545 for (i = 0; i < a_renames->nr; i++) {
2546 sre = a_renames->items[i].util;
2547 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2548 = (void *)sre;
2549 }
2550 for (i = 0; i < b_renames->nr; i++) {
2551 sre = b_renames->items[i].util;
2552 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2553 = (void *)sre;
2554 }
2555
2556 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2557 struct string_list *renames1, *renames2Dst;
2558 struct rename *ren1 = NULL, *ren2 = NULL;
2559 const char *branch1, *branch2;
2560 const char *ren1_src, *ren1_dst;
2561 struct string_list_item *lookup;
2562
2563 if (i >= a_renames->nr) {
2564 ren2 = b_renames->items[j++].util;
2565 } else if (j >= b_renames->nr) {
2566 ren1 = a_renames->items[i++].util;
2567 } else {
2568 int compare = strcmp(a_renames->items[i].string,
2569 b_renames->items[j].string);
2570 if (compare <= 0)
2571 ren1 = a_renames->items[i++].util;
2572 if (compare >= 0)
2573 ren2 = b_renames->items[j++].util;
2574 }
2575
2576 /* TODO: refactor, so that 1/2 are not needed */
2577 if (ren1) {
2578 renames1 = a_renames;
2579 renames2Dst = &b_by_dst;
2580 branch1 = o->branch1;
2581 branch2 = o->branch2;
2582 } else {
2583 renames1 = b_renames;
2584 renames2Dst = &a_by_dst;
2585 branch1 = o->branch2;
2586 branch2 = o->branch1;
2587 SWAP(ren2, ren1);
2588 }
2589
2590 if (ren1->processed)
2591 continue;
2592 ren1->processed = 1;
2593 ren1->dst_entry->processed = 1;
2594 /* BUG: We should only mark src_entry as processed if we
2595 * are not dealing with a rename + add-source case.
2596 */
2597 ren1->src_entry->processed = 1;
2598
2599 ren1_src = ren1->pair->one->path;
2600 ren1_dst = ren1->pair->two->path;
2601
2602 if (ren2) {
2603 /* One file renamed on both sides */
2604 const char *ren2_src = ren2->pair->one->path;
2605 const char *ren2_dst = ren2->pair->two->path;
2606 enum rename_type rename_type;
2607 if (strcmp(ren1_src, ren2_src) != 0)
2608 BUG("ren1_src != ren2_src");
2609 ren2->dst_entry->processed = 1;
2610 ren2->processed = 1;
2611 if (strcmp(ren1_dst, ren2_dst) != 0) {
2612 rename_type = RENAME_ONE_FILE_TO_TWO;
2613 clean_merge = 0;
2614 } else {
2615 rename_type = RENAME_ONE_FILE_TO_ONE;
2616 /* BUG: We should only remove ren1_src in
2617 * the base stage (think of rename +
2618 * add-source cases).
2619 */
2620 remove_file(o, 1, ren1_src, 1);
2621 update_entry(ren1->dst_entry,
2622 ren1->pair->one,
2623 ren1->pair->two,
2624 ren2->pair->two);
2625 }
2626 setup_rename_conflict_info(rename_type,
2627 ren1->pair,
2628 ren2->pair,
2629 branch1,
2630 branch2,
2631 ren1->dst_entry,
2632 ren2->dst_entry,
2633 o,
2634 NULL,
2635 NULL);
2636 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2637 /* Two different files renamed to the same thing */
2638 char *ren2_dst;
2639 ren2 = lookup->util;
2640 ren2_dst = ren2->pair->two->path;
2641 if (strcmp(ren1_dst, ren2_dst) != 0)
2642 BUG("ren1_dst != ren2_dst");
2643
2644 clean_merge = 0;
2645 ren2->processed = 1;
2646 /*
2647 * BUG: We should only mark src_entry as processed
2648 * if we are not dealing with a rename + add-source
2649 * case.
2650 */
2651 ren2->src_entry->processed = 1;
2652
2653 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2654 ren1->pair,
2655 ren2->pair,
2656 branch1,
2657 branch2,
2658 ren1->dst_entry,
2659 ren2->dst_entry,
2660 o,
2661 ren1->src_entry,
2662 ren2->src_entry);
2663
2664 } else {
2665 /* Renamed in 1, maybe changed in 2 */
2666 /* we only use sha1 and mode of these */
2667 struct diff_filespec src_other, dst_other;
2668 int try_merge;
2669
2670 /*
2671 * unpack_trees loads entries from common-commit
2672 * into stage 1, from head-commit into stage 2, and
2673 * from merge-commit into stage 3. We keep track
2674 * of which side corresponds to the rename.
2675 */
2676 int renamed_stage = a_renames == renames1 ? 2 : 3;
2677 int other_stage = a_renames == renames1 ? 3 : 2;
2678
2679 /* BUG: We should only remove ren1_src in the base
2680 * stage and in other_stage (think of rename +
2681 * add-source case).
2682 */
2683 remove_file(o, 1, ren1_src,
2684 renamed_stage == 2 || !was_tracked(o, ren1_src));
2685
2686 oidcpy(&src_other.oid,
2687 &ren1->src_entry->stages[other_stage].oid);
2688 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2689 oidcpy(&dst_other.oid,
2690 &ren1->dst_entry->stages[other_stage].oid);
2691 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2692 try_merge = 0;
2693
2694 if (oid_eq(&src_other.oid, &null_oid) &&
2695 ren1->add_turned_into_rename) {
2696 setup_rename_conflict_info(RENAME_VIA_DIR,
2697 ren1->pair,
2698 NULL,
2699 branch1,
2700 branch2,
2701 ren1->dst_entry,
2702 NULL,
2703 o,
2704 NULL,
2705 NULL);
2706 } else if (oid_eq(&src_other.oid, &null_oid)) {
2707 setup_rename_conflict_info(RENAME_DELETE,
2708 ren1->pair,
2709 NULL,
2710 branch1,
2711 branch2,
2712 ren1->dst_entry,
2713 NULL,
2714 o,
2715 NULL,
2716 NULL);
2717 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2718 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2719 /*
2720 * Added file on the other side identical to
2721 * the file being renamed: clean merge.
2722 * Also, there is no need to overwrite the
2723 * file already in the working copy, so call
2724 * update_file_flags() instead of
2725 * update_file().
2726 */
2727 if (update_file_flags(o,
2728 &ren1->pair->two->oid,
2729 ren1->pair->two->mode,
2730 ren1_dst,
2731 1, /* update_cache */
2732 0 /* update_wd */))
2733 clean_merge = -1;
2734 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2735 clean_merge = 0;
2736 try_merge = 1;
2737 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
2738 "%s added in %s"),
2739 ren1_src, ren1_dst, branch1,
2740 ren1_dst, branch2);
2741 if (o->call_depth) {
2742 struct merge_file_info mfi;
2743 struct diff_filespec one, a, b;
2744
2745 oidcpy(&one.oid, &null_oid);
2746 one.mode = 0;
2747 one.path = ren1->pair->two->path;
2748
2749 oidcpy(&a.oid, &ren1->pair->two->oid);
2750 a.mode = ren1->pair->two->mode;
2751 a.path = one.path;
2752
2753 oidcpy(&b.oid, &dst_other.oid);
2754 b.mode = dst_other.mode;
2755 b.path = one.path;
2756
2757 if (merge_mode_and_contents(o, &one, &a, &b, ren1_dst,
2758 branch1, branch2,
2759 &mfi)) {
2760 clean_merge = -1;
2761 goto cleanup_and_return;
2762 }
2763 output(o, 1, _("Adding merged %s"), ren1_dst);
2764 if (update_file(o, 0, &mfi.oid,
2765 mfi.mode, ren1_dst))
2766 clean_merge = -1;
2767 try_merge = 0;
2768 } else {
2769 char *new_path = unique_path(o, ren1_dst, branch2);
2770 output(o, 1, _("Adding as %s instead"), new_path);
2771 if (update_file(o, 0, &dst_other.oid,
2772 dst_other.mode, new_path))
2773 clean_merge = -1;
2774 free(new_path);
2775 }
2776 } else
2777 try_merge = 1;
2778
2779 if (clean_merge < 0)
2780 goto cleanup_and_return;
2781 if (try_merge) {
2782 struct diff_filespec *one, *a, *b;
2783 src_other.path = (char *)ren1_src;
2784
2785 one = ren1->pair->one;
2786 if (a_renames == renames1) {
2787 a = ren1->pair->two;
2788 b = &src_other;
2789 } else {
2790 b = ren1->pair->two;
2791 a = &src_other;
2792 }
2793 update_entry(ren1->dst_entry, one, a, b);
2794 setup_rename_conflict_info(RENAME_NORMAL,
2795 ren1->pair,
2796 NULL,
2797 branch1,
2798 NULL,
2799 ren1->dst_entry,
2800 NULL,
2801 o,
2802 NULL,
2803 NULL);
2804 }
2805 }
2806 }
2807 cleanup_and_return:
2808 string_list_clear(&a_by_dst, 0);
2809 string_list_clear(&b_by_dst, 0);
2810
2811 return clean_merge;
2812 }
2813
2814 struct rename_info {
2815 struct string_list *head_renames;
2816 struct string_list *merge_renames;
2817 };
2818
2819 static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2820 struct hashmap *dir_renames)
2821 {
2822 struct hashmap_iter iter;
2823 struct dir_rename_entry *e;
2824
2825 hashmap_iter_init(dir_renames, &iter);
2826 while ((e = hashmap_iter_next(&iter))) {
2827 free(e->dir);
2828 strbuf_release(&e->new_dir);
2829 /* possible_new_dirs already cleared in get_directory_renames */
2830 }
2831 hashmap_free(dir_renames, 1);
2832 free(dir_renames);
2833
2834 free(pairs->queue);
2835 free(pairs);
2836 }
2837
2838 static int detect_and_process_renames(struct merge_options *o,
2839 struct tree *common,
2840 struct tree *head,
2841 struct tree *merge,
2842 struct string_list *entries,
2843 struct rename_info *ri)
2844 {
2845 struct diff_queue_struct *head_pairs, *merge_pairs;
2846 struct hashmap *dir_re_head, *dir_re_merge;
2847 int clean = 1;
2848
2849 ri->head_renames = NULL;
2850 ri->merge_renames = NULL;
2851
2852 if (!merge_detect_rename(o))
2853 return 1;
2854
2855 head_pairs = get_diffpairs(o, common, head);
2856 merge_pairs = get_diffpairs(o, common, merge);
2857
2858 if (o->detect_directory_renames) {
2859 dir_re_head = get_directory_renames(head_pairs, head);
2860 dir_re_merge = get_directory_renames(merge_pairs, merge);
2861
2862 handle_directory_level_conflicts(o,
2863 dir_re_head, head,
2864 dir_re_merge, merge);
2865 } else {
2866 dir_re_head = xmalloc(sizeof(*dir_re_head));
2867 dir_re_merge = xmalloc(sizeof(*dir_re_merge));
2868 dir_rename_init(dir_re_head);
2869 dir_rename_init(dir_re_merge);
2870 }
2871
2872 ri->head_renames = get_renames(o, head_pairs,
2873 dir_re_merge, dir_re_head, head,
2874 common, head, merge, entries,
2875 &clean);
2876 if (clean < 0)
2877 goto cleanup;
2878 ri->merge_renames = get_renames(o, merge_pairs,
2879 dir_re_head, dir_re_merge, merge,
2880 common, head, merge, entries,
2881 &clean);
2882 if (clean < 0)
2883 goto cleanup;
2884 clean &= process_renames(o, ri->head_renames, ri->merge_renames);
2885
2886 cleanup:
2887 /*
2888 * Some cleanup is deferred until cleanup_renames() because the
2889 * data structures are still needed and referenced in
2890 * process_entry(). But there are a few things we can free now.
2891 */
2892 initial_cleanup_rename(head_pairs, dir_re_head);
2893 initial_cleanup_rename(merge_pairs, dir_re_merge);
2894
2895 return clean;
2896 }
2897
2898 static void final_cleanup_rename(struct string_list *rename)
2899 {
2900 const struct rename *re;
2901 int i;
2902
2903 if (rename == NULL)
2904 return;
2905
2906 for (i = 0; i < rename->nr; i++) {
2907 re = rename->items[i].util;
2908 diff_free_filepair(re->pair);
2909 }
2910 string_list_clear(rename, 1);
2911 free(rename);
2912 }
2913
2914 static void final_cleanup_renames(struct rename_info *re_info)
2915 {
2916 final_cleanup_rename(re_info->head_renames);
2917 final_cleanup_rename(re_info->merge_renames);
2918 }
2919
2920 static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
2921 {
2922 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
2923 }
2924
2925 static int read_oid_strbuf(struct merge_options *o,
2926 const struct object_id *oid,
2927 struct strbuf *dst)
2928 {
2929 void *buf;
2930 enum object_type type;
2931 unsigned long size;
2932 buf = read_object_file(oid, &type, &size);
2933 if (!buf)
2934 return err(o, _("cannot read object %s"), oid_to_hex(oid));
2935 if (type != OBJ_BLOB) {
2936 free(buf);
2937 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
2938 }
2939 strbuf_attach(dst, buf, size, size + 1);
2940 return 0;
2941 }
2942
2943 static int blob_unchanged(struct merge_options *opt,
2944 const struct object_id *o_oid,
2945 unsigned o_mode,
2946 const struct object_id *a_oid,
2947 unsigned a_mode,
2948 int renormalize, const char *path)
2949 {
2950 struct strbuf o = STRBUF_INIT;
2951 struct strbuf a = STRBUF_INIT;
2952 int ret = 0; /* assume changed for safety */
2953
2954 if (a_mode != o_mode)
2955 return 0;
2956 if (oid_eq(o_oid, a_oid))
2957 return 1;
2958 if (!renormalize)
2959 return 0;
2960
2961 assert(o_oid && a_oid);
2962 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
2963 goto error_return;
2964 /*
2965 * Note: binary | is used so that both renormalizations are
2966 * performed. Comparison can be skipped if both files are
2967 * unchanged since their sha1s have already been compared.
2968 */
2969 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
2970 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
2971 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
2972
2973 error_return:
2974 strbuf_release(&o);
2975 strbuf_release(&a);
2976 return ret;
2977 }
2978
2979 static int handle_modify_delete(struct merge_options *o,
2980 const char *path,
2981 struct object_id *o_oid, int o_mode,
2982 struct object_id *a_oid, int a_mode,
2983 struct object_id *b_oid, int b_mode)
2984 {
2985 const char *modify_branch, *delete_branch;
2986 struct object_id *changed_oid;
2987 int changed_mode;
2988
2989 if (a_oid) {
2990 modify_branch = o->branch1;
2991 delete_branch = o->branch2;
2992 changed_oid = a_oid;
2993 changed_mode = a_mode;
2994 } else {
2995 modify_branch = o->branch2;
2996 delete_branch = o->branch1;
2997 changed_oid = b_oid;
2998 changed_mode = b_mode;
2999 }
3000
3001 return handle_change_delete(o,
3002 path, NULL,
3003 o_oid, o_mode,
3004 changed_oid, changed_mode,
3005 modify_branch, delete_branch,
3006 _("modify"), _("modified"));
3007 }
3008
3009 static int handle_content_merge(struct merge_options *o,
3010 const char *path,
3011 int is_dirty,
3012 struct object_id *o_oid, int o_mode,
3013 struct object_id *a_oid, int a_mode,
3014 struct object_id *b_oid, int b_mode,
3015 struct rename_conflict_info *rename_conflict_info)
3016 {
3017 const char *reason = _("content");
3018 const char *path1 = NULL, *path2 = NULL;
3019 struct merge_file_info mfi;
3020 struct diff_filespec one, a, b;
3021 unsigned df_conflict_remains = 0;
3022
3023 if (!o_oid) {
3024 reason = _("add/add");
3025 o_oid = (struct object_id *)&null_oid;
3026 }
3027 one.path = a.path = b.path = (char *)path;
3028 oidcpy(&one.oid, o_oid);
3029 one.mode = o_mode;
3030 oidcpy(&a.oid, a_oid);
3031 a.mode = a_mode;
3032 oidcpy(&b.oid, b_oid);
3033 b.mode = b_mode;
3034
3035 if (rename_conflict_info) {
3036 struct diff_filepair *pair1 = rename_conflict_info->pair1;
3037
3038 path1 = (o->branch1 == rename_conflict_info->branch1) ?
3039 pair1->two->path : pair1->one->path;
3040 /* If rename_conflict_info->pair2 != NULL, we are in
3041 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
3042 * normal rename.
3043 */
3044 path2 = (rename_conflict_info->pair2 ||
3045 o->branch2 == rename_conflict_info->branch1) ?
3046 pair1->two->path : pair1->one->path;
3047 one.path = pair1->one->path;
3048 a.path = (char *)path1;
3049 b.path = (char *)path2;
3050
3051 if (dir_in_way(path, !o->call_depth,
3052 S_ISGITLINK(pair1->two->mode)))
3053 df_conflict_remains = 1;
3054 }
3055 if (merge_mode_and_contents(o, &one, &a, &b, path,
3056 o->branch1, o->branch2, &mfi))
3057 return -1;
3058
3059 /*
3060 * We can skip updating the working tree file iff:
3061 * a) The merge is clean
3062 * b) The merge matches what was in HEAD (content, mode, pathname)
3063 * c) The target path is usable (i.e. not involved in D/F conflict)
3064 */
3065 if (mfi.clean &&
3066 was_tracked_and_matches(o, path, &mfi.oid, mfi.mode) &&
3067 !df_conflict_remains) {
3068 int pos;
3069 struct cache_entry *ce;
3070
3071 output(o, 3, _("Skipped %s (merged same as existing)"), path);
3072 if (add_cacheinfo(o, mfi.mode, &mfi.oid, path,
3073 0, (!o->call_depth && !is_dirty), 0))
3074 return -1;
3075 /*
3076 * However, add_cacheinfo() will delete the old cache entry
3077 * and add a new one. We need to copy over any skip_worktree
3078 * flag to avoid making the file appear as if it were
3079 * deleted by the user.
3080 */
3081 pos = index_name_pos(&o->orig_index, path, strlen(path));
3082 ce = o->orig_index.cache[pos];
3083 if (ce_skip_worktree(ce)) {
3084 pos = index_name_pos(&the_index, path, strlen(path));
3085 ce = the_index.cache[pos];
3086 ce->ce_flags |= CE_SKIP_WORKTREE;
3087 }
3088 return mfi.clean;
3089 }
3090
3091 if (!mfi.clean) {
3092 if (S_ISGITLINK(mfi.mode))
3093 reason = _("submodule");
3094 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
3095 reason, path);
3096 if (rename_conflict_info && !df_conflict_remains)
3097 if (update_stages(o, path, &one, &a, &b))
3098 return -1;
3099 }
3100
3101 if (df_conflict_remains || is_dirty) {
3102 char *new_path;
3103 if (o->call_depth) {
3104 remove_file_from_cache(path);
3105 } else {
3106 if (!mfi.clean) {
3107 if (update_stages(o, path, &one, &a, &b))
3108 return -1;
3109 } else {
3110 int file_from_stage2 = was_tracked(o, path);
3111 struct diff_filespec merged;
3112 oidcpy(&merged.oid, &mfi.oid);
3113 merged.mode = mfi.mode;
3114
3115 if (update_stages(o, path, NULL,
3116 file_from_stage2 ? &merged : NULL,
3117 file_from_stage2 ? NULL : &merged))
3118 return -1;
3119 }
3120
3121 }
3122 new_path = unique_path(o, path, rename_conflict_info->branch1);
3123 if (is_dirty) {
3124 output(o, 1, _("Refusing to lose dirty file at %s"),
3125 path);
3126 }
3127 output(o, 1, _("Adding as %s instead"), new_path);
3128 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
3129 free(new_path);
3130 return -1;
3131 }
3132 free(new_path);
3133 mfi.clean = 0;
3134 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
3135 return -1;
3136 return !is_dirty && mfi.clean;
3137 }
3138
3139 static int handle_rename_normal(struct merge_options *o,
3140 const char *path,
3141 struct object_id *o_oid, unsigned int o_mode,
3142 struct object_id *a_oid, unsigned int a_mode,
3143 struct object_id *b_oid, unsigned int b_mode,
3144 struct rename_conflict_info *ci)
3145 {
3146 /* Merge the content and write it out */
3147 return handle_content_merge(o, path, was_dirty(o, path),
3148 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3149 ci);
3150 }
3151
3152 /* Per entry merge function */
3153 static int process_entry(struct merge_options *o,
3154 const char *path, struct stage_data *entry)
3155 {
3156 int clean_merge = 1;
3157 int normalize = o->renormalize;
3158 unsigned o_mode = entry->stages[1].mode;
3159 unsigned a_mode = entry->stages[2].mode;
3160 unsigned b_mode = entry->stages[3].mode;
3161 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
3162 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
3163 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
3164
3165 entry->processed = 1;
3166 if (entry->rename_conflict_info) {
3167 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
3168 switch (conflict_info->rename_type) {
3169 case RENAME_NORMAL:
3170 case RENAME_ONE_FILE_TO_ONE:
3171 clean_merge = handle_rename_normal(o,
3172 path,
3173 o_oid, o_mode,
3174 a_oid, a_mode,
3175 b_oid, b_mode,
3176 conflict_info);
3177 break;
3178 case RENAME_VIA_DIR:
3179 clean_merge = 1;
3180 if (handle_rename_via_dir(o,
3181 conflict_info->pair1,
3182 conflict_info->branch1,
3183 conflict_info->branch2))
3184 clean_merge = -1;
3185 break;
3186 case RENAME_DELETE:
3187 clean_merge = 0;
3188 if (handle_rename_delete(o,
3189 conflict_info->pair1,
3190 conflict_info->branch1,
3191 conflict_info->branch2))
3192 clean_merge = -1;
3193 break;
3194 case RENAME_ONE_FILE_TO_TWO:
3195 clean_merge = 0;
3196 if (handle_rename_rename_1to2(o, conflict_info))
3197 clean_merge = -1;
3198 break;
3199 case RENAME_TWO_FILES_TO_ONE:
3200 clean_merge = 0;
3201 if (handle_rename_rename_2to1(o, conflict_info))
3202 clean_merge = -1;
3203 break;
3204 default:
3205 entry->processed = 0;
3206 break;
3207 }
3208 } else if (o_oid && (!a_oid || !b_oid)) {
3209 /* Case A: Deleted in one */
3210 if ((!a_oid && !b_oid) ||
3211 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
3212 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
3213 /* Deleted in both or deleted in one and
3214 * unchanged in the other */
3215 if (a_oid)
3216 output(o, 2, _("Removing %s"), path);
3217 /* do not touch working file if it did not exist */
3218 remove_file(o, 1, path, !a_oid);
3219 } else {
3220 /* Modify/delete; deleted side may have put a directory in the way */
3221 clean_merge = 0;
3222 if (handle_modify_delete(o, path, o_oid, o_mode,
3223 a_oid, a_mode, b_oid, b_mode))
3224 clean_merge = -1;
3225 }
3226 } else if ((!o_oid && a_oid && !b_oid) ||
3227 (!o_oid && !a_oid && b_oid)) {
3228 /* Case B: Added in one. */
3229 /* [nothing|directory] -> ([nothing|directory], file) */
3230
3231 const char *add_branch;
3232 const char *other_branch;
3233 unsigned mode;
3234 const struct object_id *oid;
3235 const char *conf;
3236
3237 if (a_oid) {
3238 add_branch = o->branch1;
3239 other_branch = o->branch2;
3240 mode = a_mode;
3241 oid = a_oid;
3242 conf = _("file/directory");
3243 } else {
3244 add_branch = o->branch2;
3245 other_branch = o->branch1;
3246 mode = b_mode;
3247 oid = b_oid;
3248 conf = _("directory/file");
3249 }
3250 if (dir_in_way(path,
3251 !o->call_depth && !S_ISGITLINK(a_mode),
3252 0)) {
3253 char *new_path = unique_path(o, path, add_branch);
3254 clean_merge = 0;
3255 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
3256 "Adding %s as %s"),
3257 conf, path, other_branch, path, new_path);
3258 if (update_file(o, 0, oid, mode, new_path))
3259 clean_merge = -1;
3260 else if (o->call_depth)
3261 remove_file_from_cache(path);
3262 free(new_path);
3263 } else {
3264 output(o, 2, _("Adding %s"), path);
3265 /* do not overwrite file if already present */
3266 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
3267 clean_merge = -1;
3268 }
3269 } else if (a_oid && b_oid) {
3270 /* Case C: Added in both (check for same permissions) and */
3271 /* case D: Modified in both, but differently. */
3272 int is_dirty = 0; /* unpack_trees would have bailed if dirty */
3273 clean_merge = handle_content_merge(o, path, is_dirty,
3274 o_oid, o_mode,
3275 a_oid, a_mode,
3276 b_oid, b_mode,
3277 NULL);
3278 } else if (!o_oid && !a_oid && !b_oid) {
3279 /*
3280 * this entry was deleted altogether. a_mode == 0 means
3281 * we had that path and want to actively remove it.
3282 */
3283 remove_file(o, 1, path, !a_mode);
3284 } else
3285 BUG("fatal merge failure, shouldn't happen.");
3286
3287 return clean_merge;
3288 }
3289
3290 int merge_trees(struct merge_options *o,
3291 struct tree *head,
3292 struct tree *merge,
3293 struct tree *common,
3294 struct tree **result)
3295 {
3296 int code, clean;
3297 struct strbuf sb = STRBUF_INIT;
3298
3299 if (!o->call_depth && index_has_changes(&the_index, head, &sb)) {
3300 err(o, _("Your local changes to the following files would be overwritten by merge:\n %s"),
3301 sb.buf);
3302 return -1;
3303 }
3304
3305 if (o->subtree_shift) {
3306 merge = shift_tree_object(head, merge, o->subtree_shift);
3307 common = shift_tree_object(head, common, o->subtree_shift);
3308 }
3309
3310 if (oid_eq(&common->object.oid, &merge->object.oid)) {
3311 output(o, 0, _("Already up to date!"));
3312 *result = head;
3313 return 1;
3314 }
3315
3316 code = unpack_trees_start(o, common, head, merge);
3317
3318 if (code != 0) {
3319 if (show(o, 4) || o->call_depth)
3320 err(o, _("merging of trees %s and %s failed"),
3321 oid_to_hex(&head->object.oid),
3322 oid_to_hex(&merge->object.oid));
3323 unpack_trees_finish(o);
3324 return -1;
3325 }
3326
3327 if (unmerged_cache()) {
3328 struct string_list *entries;
3329 struct rename_info re_info;
3330 int i;
3331 /*
3332 * Only need the hashmap while processing entries, so
3333 * initialize it here and free it when we are done running
3334 * through the entries. Keeping it in the merge_options as
3335 * opposed to decaring a local hashmap is for convenience
3336 * so that we don't have to pass it to around.
3337 */
3338 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
3339 get_files_dirs(o, head);
3340 get_files_dirs(o, merge);
3341
3342 entries = get_unmerged();
3343 clean = detect_and_process_renames(o, common, head, merge,
3344 entries, &re_info);
3345 record_df_conflict_files(o, entries);
3346 if (clean < 0)
3347 goto cleanup;
3348 for (i = entries->nr-1; 0 <= i; i--) {
3349 const char *path = entries->items[i].string;
3350 struct stage_data *e = entries->items[i].util;
3351 if (!e->processed) {
3352 int ret = process_entry(o, path, e);
3353 if (!ret)
3354 clean = 0;
3355 else if (ret < 0) {
3356 clean = ret;
3357 goto cleanup;
3358 }
3359 }
3360 }
3361 for (i = 0; i < entries->nr; i++) {
3362 struct stage_data *e = entries->items[i].util;
3363 if (!e->processed)
3364 BUG("unprocessed path??? %s",
3365 entries->items[i].string);
3366 }
3367
3368 cleanup:
3369 final_cleanup_renames(&re_info);
3370
3371 string_list_clear(entries, 1);
3372 free(entries);
3373
3374 hashmap_free(&o->current_file_dir_set, 1);
3375
3376 if (clean < 0) {
3377 unpack_trees_finish(o);
3378 return clean;
3379 }
3380 }
3381 else
3382 clean = 1;
3383
3384 unpack_trees_finish(o);
3385
3386 if (o->call_depth && !(*result = write_tree_from_memory(o)))
3387 return -1;
3388
3389 return clean;
3390 }
3391
3392 static struct commit_list *reverse_commit_list(struct commit_list *list)
3393 {
3394 struct commit_list *next = NULL, *current, *backup;
3395 for (current = list; current; current = backup) {
3396 backup = current->next;
3397 current->next = next;
3398 next = current;
3399 }
3400 return next;
3401 }
3402
3403 /*
3404 * Merge the commits h1 and h2, return the resulting virtual
3405 * commit object and a flag indicating the cleanness of the merge.
3406 */
3407 int merge_recursive(struct merge_options *o,
3408 struct commit *h1,
3409 struct commit *h2,
3410 struct commit_list *ca,
3411 struct commit **result)
3412 {
3413 struct commit_list *iter;
3414 struct commit *merged_common_ancestors;
3415 struct tree *mrtree;
3416 int clean;
3417
3418 if (show(o, 4)) {
3419 output(o, 4, _("Merging:"));
3420 output_commit_title(o, h1);
3421 output_commit_title(o, h2);
3422 }
3423
3424 if (!ca) {
3425 ca = get_merge_bases(h1, h2);
3426 ca = reverse_commit_list(ca);
3427 }
3428
3429 if (show(o, 5)) {
3430 unsigned cnt = commit_list_count(ca);
3431
3432 output(o, 5, Q_("found %u common ancestor:",
3433 "found %u common ancestors:", cnt), cnt);
3434 for (iter = ca; iter; iter = iter->next)
3435 output_commit_title(o, iter->item);
3436 }
3437
3438 merged_common_ancestors = pop_commit(&ca);
3439 if (merged_common_ancestors == NULL) {
3440 /* if there is no common ancestor, use an empty tree */
3441 struct tree *tree;
3442
3443 tree = lookup_tree(the_repository, the_repository->hash_algo->empty_tree);
3444 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
3445 }
3446
3447 for (iter = ca; iter; iter = iter->next) {
3448 const char *saved_b1, *saved_b2;
3449 o->call_depth++;
3450 /*
3451 * When the merge fails, the result contains files
3452 * with conflict markers. The cleanness flag is
3453 * ignored (unless indicating an error), it was never
3454 * actually used, as result of merge_trees has always
3455 * overwritten it: the committed "conflicts" were
3456 * already resolved.
3457 */
3458 discard_cache();
3459 saved_b1 = o->branch1;
3460 saved_b2 = o->branch2;
3461 o->branch1 = "Temporary merge branch 1";
3462 o->branch2 = "Temporary merge branch 2";
3463 if (merge_recursive(o, merged_common_ancestors, iter->item,
3464 NULL, &merged_common_ancestors) < 0)
3465 return -1;
3466 o->branch1 = saved_b1;
3467 o->branch2 = saved_b2;
3468 o->call_depth--;
3469
3470 if (!merged_common_ancestors)
3471 return err(o, _("merge returned no commit"));
3472 }
3473
3474 discard_cache();
3475 if (!o->call_depth)
3476 read_cache();
3477
3478 o->ancestor = "merged common ancestors";
3479 clean = merge_trees(o, get_commit_tree(h1), get_commit_tree(h2),
3480 get_commit_tree(merged_common_ancestors),
3481 &mrtree);
3482 if (clean < 0) {
3483 flush_output(o);
3484 return clean;
3485 }
3486
3487 if (o->call_depth) {
3488 *result = make_virtual_commit(mrtree, "merged tree");
3489 commit_list_insert(h1, &(*result)->parents);
3490 commit_list_insert(h2, &(*result)->parents->next);
3491 }
3492 flush_output(o);
3493 if (!o->call_depth && o->buffer_output < 2)
3494 strbuf_release(&o->obuf);
3495 if (show(o, 2))
3496 diff_warn_rename_limit("merge.renamelimit",
3497 o->needed_rename_limit, 0);
3498 return clean;
3499 }
3500
3501 static struct commit *get_ref(const struct object_id *oid, const char *name)
3502 {
3503 struct object *object;
3504
3505 object = deref_tag(the_repository, parse_object(the_repository, oid),
3506 name,
3507 strlen(name));
3508 if (!object)
3509 return NULL;
3510 if (object->type == OBJ_TREE)
3511 return make_virtual_commit((struct tree*)object, name);
3512 if (object->type != OBJ_COMMIT)
3513 return NULL;
3514 if (parse_commit((struct commit *)object))
3515 return NULL;
3516 return (struct commit *)object;
3517 }
3518
3519 int merge_recursive_generic(struct merge_options *o,
3520 const struct object_id *head,
3521 const struct object_id *merge,
3522 int num_base_list,
3523 const struct object_id **base_list,
3524 struct commit **result)
3525 {
3526 int clean;
3527 struct lock_file lock = LOCK_INIT;
3528 struct commit *head_commit = get_ref(head, o->branch1);
3529 struct commit *next_commit = get_ref(merge, o->branch2);
3530 struct commit_list *ca = NULL;
3531
3532 if (base_list) {
3533 int i;
3534 for (i = 0; i < num_base_list; ++i) {
3535 struct commit *base;
3536 if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i]))))
3537 return err(o, _("Could not parse object '%s'"),
3538 oid_to_hex(base_list[i]));
3539 commit_list_insert(base, &ca);
3540 }
3541 }
3542
3543 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
3544 clean = merge_recursive(o, head_commit, next_commit, ca,
3545 result);
3546 if (clean < 0) {
3547 rollback_lock_file(&lock);
3548 return clean;
3549 }
3550
3551 if (write_locked_index(&the_index, &lock,
3552 COMMIT_LOCK | SKIP_IF_UNCHANGED))
3553 return err(o, _("Unable to write index."));
3554
3555 return clean ? 0 : 1;
3556 }
3557
3558 static void merge_recursive_config(struct merge_options *o)
3559 {
3560 char *value = NULL;
3561 git_config_get_int("merge.verbosity", &o->verbosity);
3562 git_config_get_int("diff.renamelimit", &o->diff_rename_limit);
3563 git_config_get_int("merge.renamelimit", &o->merge_rename_limit);
3564 if (!git_config_get_string("diff.renames", &value)) {
3565 o->diff_detect_rename = git_config_rename("diff.renames", value);
3566 free(value);
3567 }
3568 if (!git_config_get_string("merge.renames", &value)) {
3569 o->merge_detect_rename = git_config_rename("merge.renames", value);
3570 free(value);
3571 }
3572 git_config(git_xmerge_config, NULL);
3573 }
3574
3575 void init_merge_options(struct merge_options *o)
3576 {
3577 const char *merge_verbosity;
3578 memset(o, 0, sizeof(struct merge_options));
3579 o->verbosity = 2;
3580 o->buffer_output = 1;
3581 o->diff_rename_limit = -1;
3582 o->merge_rename_limit = -1;
3583 o->renormalize = 0;
3584 o->diff_detect_rename = -1;
3585 o->merge_detect_rename = -1;
3586 o->detect_directory_renames = 1;
3587 merge_recursive_config(o);
3588 merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
3589 if (merge_verbosity)
3590 o->verbosity = strtol(merge_verbosity, NULL, 10);
3591 if (o->verbosity >= 5)
3592 o->buffer_output = 0;
3593 strbuf_init(&o->obuf, 0);
3594 string_list_init(&o->df_conflict_file_set, 1);
3595 }
3596
3597 int parse_merge_opt(struct merge_options *o, const char *s)
3598 {
3599 const char *arg;
3600
3601 if (!s || !*s)
3602 return -1;
3603 if (!strcmp(s, "ours"))
3604 o->recursive_variant = MERGE_RECURSIVE_OURS;
3605 else if (!strcmp(s