tree.c: make read_tree*() take 'struct repository *'
[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(the_repository, tree, "", 0, 0,
467 &match_all, save_files_dirs, o);
468 }
469
470 static int get_tree_entry_if_blob(const struct object_id *tree,
471 const char *path,
472 struct object_id *hashy,
473 unsigned int *mode_o)
474 {
475 int ret;
476
477 ret = get_tree_entry(tree, path, hashy, mode_o);
478 if (S_ISDIR(*mode_o)) {
479 oidcpy(hashy, &null_oid);
480 *mode_o = 0;
481 }
482 return ret;
483 }
484
485 /*
486 * Returns an index_entry instance which doesn't have to correspond to
487 * a real cache entry in Git's index.
488 */
489 static struct stage_data *insert_stage_data(const char *path,
490 struct tree *o, struct tree *a, struct tree *b,
491 struct string_list *entries)
492 {
493 struct string_list_item *item;
494 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
495 get_tree_entry_if_blob(&o->object.oid, path,
496 &e->stages[1].oid, &e->stages[1].mode);
497 get_tree_entry_if_blob(&a->object.oid, path,
498 &e->stages[2].oid, &e->stages[2].mode);
499 get_tree_entry_if_blob(&b->object.oid, path,
500 &e->stages[3].oid, &e->stages[3].mode);
501 item = string_list_insert(entries, path);
502 item->util = e;
503 return e;
504 }
505
506 /*
507 * Create a dictionary mapping file names to stage_data objects. The
508 * dictionary contains one entry for every path with a non-zero stage entry.
509 */
510 static struct string_list *get_unmerged(void)
511 {
512 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
513 int i;
514
515 unmerged->strdup_strings = 1;
516
517 for (i = 0; i < active_nr; i++) {
518 struct string_list_item *item;
519 struct stage_data *e;
520 const struct cache_entry *ce = active_cache[i];
521 if (!ce_stage(ce))
522 continue;
523
524 item = string_list_lookup(unmerged, ce->name);
525 if (!item) {
526 item = string_list_insert(unmerged, ce->name);
527 item->util = xcalloc(1, sizeof(struct stage_data));
528 }
529 e = item->util;
530 e->stages[ce_stage(ce)].mode = ce->ce_mode;
531 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
532 }
533
534 return unmerged;
535 }
536
537 static int string_list_df_name_compare(const char *one, const char *two)
538 {
539 int onelen = strlen(one);
540 int twolen = strlen(two);
541 /*
542 * Here we only care that entries for D/F conflicts are
543 * adjacent, in particular with the file of the D/F conflict
544 * appearing before files below the corresponding directory.
545 * The order of the rest of the list is irrelevant for us.
546 *
547 * To achieve this, we sort with df_name_compare and provide
548 * the mode S_IFDIR so that D/F conflicts will sort correctly.
549 * We use the mode S_IFDIR for everything else for simplicity,
550 * since in other cases any changes in their order due to
551 * sorting cause no problems for us.
552 */
553 int cmp = df_name_compare(one, onelen, S_IFDIR,
554 two, twolen, S_IFDIR);
555 /*
556 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
557 * that 'foo' comes before 'foo/bar'.
558 */
559 if (cmp)
560 return cmp;
561 return onelen - twolen;
562 }
563
564 static void record_df_conflict_files(struct merge_options *o,
565 struct string_list *entries)
566 {
567 /* If there is a D/F conflict and the file for such a conflict
568 * currently exists in the working tree, we want to allow it to be
569 * removed to make room for the corresponding directory if needed.
570 * The files underneath the directories of such D/F conflicts will
571 * be processed before the corresponding file involved in the D/F
572 * conflict. If the D/F directory ends up being removed by the
573 * merge, then we won't have to touch the D/F file. If the D/F
574 * directory needs to be written to the working copy, then the D/F
575 * file will simply be removed (in make_room_for_path()) to make
576 * room for the necessary paths. Note that if both the directory
577 * and the file need to be present, then the D/F file will be
578 * reinstated with a new unique name at the time it is processed.
579 */
580 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
581 const char *last_file = NULL;
582 int last_len = 0;
583 int i;
584
585 /*
586 * If we're merging merge-bases, we don't want to bother with
587 * any working directory changes.
588 */
589 if (o->call_depth)
590 return;
591
592 /* Ensure D/F conflicts are adjacent in the entries list. */
593 for (i = 0; i < entries->nr; i++) {
594 struct string_list_item *next = &entries->items[i];
595 string_list_append(&df_sorted_entries, next->string)->util =
596 next->util;
597 }
598 df_sorted_entries.cmp = string_list_df_name_compare;
599 string_list_sort(&df_sorted_entries);
600
601 string_list_clear(&o->df_conflict_file_set, 1);
602 for (i = 0; i < df_sorted_entries.nr; i++) {
603 const char *path = df_sorted_entries.items[i].string;
604 int len = strlen(path);
605 struct stage_data *e = df_sorted_entries.items[i].util;
606
607 /*
608 * Check if last_file & path correspond to a D/F conflict;
609 * i.e. whether path is last_file+'/'+<something>.
610 * If so, record that it's okay to remove last_file to make
611 * room for path and friends if needed.
612 */
613 if (last_file &&
614 len > last_len &&
615 memcmp(path, last_file, last_len) == 0 &&
616 path[last_len] == '/') {
617 string_list_insert(&o->df_conflict_file_set, last_file);
618 }
619
620 /*
621 * Determine whether path could exist as a file in the
622 * working directory as a possible D/F conflict. This
623 * will only occur when it exists in stage 2 as a
624 * file.
625 */
626 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
627 last_file = path;
628 last_len = len;
629 } else {
630 last_file = NULL;
631 }
632 }
633 string_list_clear(&df_sorted_entries, 0);
634 }
635
636 struct rename {
637 struct diff_filepair *pair;
638 /*
639 * Purpose of src_entry and dst_entry:
640 *
641 * If 'before' is renamed to 'after' then src_entry will contain
642 * the versions of 'before' from the merge_base, HEAD, and MERGE in
643 * stages 1, 2, and 3; dst_entry will contain the respective
644 * versions of 'after' in corresponding locations. Thus, we have a
645 * total of six modes and oids, though some will be null. (Stage 0
646 * is ignored; we're interested in handling conflicts.)
647 *
648 * Since we don't turn on break-rewrites by default, neither
649 * src_entry nor dst_entry can have all three of their stages have
650 * non-null oids, meaning at most four of the six will be non-null.
651 * Also, since this is a rename, both src_entry and dst_entry will
652 * have at least one non-null oid, meaning at least two will be
653 * non-null. Of the six oids, a typical rename will have three be
654 * non-null. Only two implies a rename/delete, and four implies a
655 * rename/add.
656 */
657 struct stage_data *src_entry;
658 struct stage_data *dst_entry;
659 unsigned add_turned_into_rename:1;
660 unsigned processed:1;
661 };
662
663 static int update_stages(struct merge_options *opt, const char *path,
664 const struct diff_filespec *o,
665 const struct diff_filespec *a,
666 const struct diff_filespec *b)
667 {
668
669 /*
670 * NOTE: It is usually a bad idea to call update_stages on a path
671 * before calling update_file on that same path, since it can
672 * sometimes lead to spurious "refusing to lose untracked file..."
673 * messages from update_file (via make_room_for path via
674 * would_lose_untracked). Instead, reverse the order of the calls
675 * (executing update_file first and then update_stages).
676 */
677 int clear = 1;
678 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
679 if (clear)
680 if (remove_file_from_cache(path))
681 return -1;
682 if (o)
683 if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options))
684 return -1;
685 if (a)
686 if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options))
687 return -1;
688 if (b)
689 if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options))
690 return -1;
691 return 0;
692 }
693
694 static int update_stages_for_stage_data(struct merge_options *opt,
695 const char *path,
696 const struct stage_data *stage_data)
697 {
698 struct diff_filespec o, a, b;
699
700 o.mode = stage_data->stages[1].mode;
701 oidcpy(&o.oid, &stage_data->stages[1].oid);
702
703 a.mode = stage_data->stages[2].mode;
704 oidcpy(&a.oid, &stage_data->stages[2].oid);
705
706 b.mode = stage_data->stages[3].mode;
707 oidcpy(&b.oid, &stage_data->stages[3].oid);
708
709 return update_stages(opt, path,
710 is_null_oid(&o.oid) ? NULL : &o,
711 is_null_oid(&a.oid) ? NULL : &a,
712 is_null_oid(&b.oid) ? NULL : &b);
713 }
714
715 static void update_entry(struct stage_data *entry,
716 struct diff_filespec *o,
717 struct diff_filespec *a,
718 struct diff_filespec *b)
719 {
720 entry->processed = 0;
721 entry->stages[1].mode = o->mode;
722 entry->stages[2].mode = a->mode;
723 entry->stages[3].mode = b->mode;
724 oidcpy(&entry->stages[1].oid, &o->oid);
725 oidcpy(&entry->stages[2].oid, &a->oid);
726 oidcpy(&entry->stages[3].oid, &b->oid);
727 }
728
729 static int remove_file(struct merge_options *o, int clean,
730 const char *path, int no_wd)
731 {
732 int update_cache = o->call_depth || clean;
733 int update_working_directory = !o->call_depth && !no_wd;
734
735 if (update_cache) {
736 if (remove_file_from_cache(path))
737 return -1;
738 }
739 if (update_working_directory) {
740 if (ignore_case) {
741 struct cache_entry *ce;
742 ce = cache_file_exists(path, strlen(path), ignore_case);
743 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
744 return 0;
745 }
746 if (remove_path(path))
747 return -1;
748 }
749 return 0;
750 }
751
752 /* add a string to a strbuf, but converting "/" to "_" */
753 static void add_flattened_path(struct strbuf *out, const char *s)
754 {
755 size_t i = out->len;
756 strbuf_addstr(out, s);
757 for (; i < out->len; i++)
758 if (out->buf[i] == '/')
759 out->buf[i] = '_';
760 }
761
762 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
763 {
764 struct path_hashmap_entry *entry;
765 struct strbuf newpath = STRBUF_INIT;
766 int suffix = 0;
767 size_t base_len;
768
769 strbuf_addf(&newpath, "%s~", path);
770 add_flattened_path(&newpath, branch);
771
772 base_len = newpath.len;
773 while (hashmap_get_from_hash(&o->current_file_dir_set,
774 path_hash(newpath.buf), newpath.buf) ||
775 (!o->call_depth && file_exists(newpath.buf))) {
776 strbuf_setlen(&newpath, base_len);
777 strbuf_addf(&newpath, "_%d", suffix++);
778 }
779
780 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
781 hashmap_entry_init(entry, path_hash(entry->path));
782 hashmap_add(&o->current_file_dir_set, entry);
783 return strbuf_detach(&newpath, NULL);
784 }
785
786 /**
787 * Check whether a directory in the index is in the way of an incoming
788 * file. Return 1 if so. If check_working_copy is non-zero, also
789 * check the working directory. If empty_ok is non-zero, also return
790 * 0 in the case where the working-tree dir exists but is empty.
791 */
792 static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
793 {
794 int pos;
795 struct strbuf dirpath = STRBUF_INIT;
796 struct stat st;
797
798 strbuf_addstr(&dirpath, path);
799 strbuf_addch(&dirpath, '/');
800
801 pos = cache_name_pos(dirpath.buf, dirpath.len);
802
803 if (pos < 0)
804 pos = -1 - pos;
805 if (pos < active_nr &&
806 !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) {
807 strbuf_release(&dirpath);
808 return 1;
809 }
810
811 strbuf_release(&dirpath);
812 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
813 !(empty_ok && is_empty_dir(path));
814 }
815
816 /*
817 * Returns whether path was tracked in the index before the merge started,
818 * and its oid and mode match the specified values
819 */
820 static int was_tracked_and_matches(struct merge_options *o, const char *path,
821 const struct object_id *oid, unsigned mode)
822 {
823 int pos = index_name_pos(&o->orig_index, path, strlen(path));
824 struct cache_entry *ce;
825
826 if (0 > pos)
827 /* we were not tracking this path before the merge */
828 return 0;
829
830 /* See if the file we were tracking before matches */
831 ce = o->orig_index.cache[pos];
832 return (oid_eq(&ce->oid, oid) && ce->ce_mode == mode);
833 }
834
835 /*
836 * Returns whether path was tracked in the index before the merge started
837 */
838 static int was_tracked(struct merge_options *o, const char *path)
839 {
840 int pos = index_name_pos(&o->orig_index, path, strlen(path));
841
842 if (0 <= pos)
843 /* we were tracking this path before the merge */
844 return 1;
845
846 return 0;
847 }
848
849 static int would_lose_untracked(const char *path)
850 {
851 /*
852 * This may look like it can be simplified to:
853 * return !was_tracked(o, path) && file_exists(path)
854 * but it can't. This function needs to know whether path was in
855 * the working tree due to EITHER having been tracked in the index
856 * before the merge OR having been put into the working copy and
857 * index by unpack_trees(). Due to that either-or requirement, we
858 * check the current index instead of the original one.
859 *
860 * Note that we do not need to worry about merge-recursive itself
861 * updating the index after unpack_trees() and before calling this
862 * function, because we strictly require all code paths in
863 * merge-recursive to update the working tree first and the index
864 * second. Doing otherwise would break
865 * update_file()/would_lose_untracked(); see every comment in this
866 * file which mentions "update_stages".
867 */
868 int pos = cache_name_pos(path, strlen(path));
869
870 if (pos < 0)
871 pos = -1 - pos;
872 while (pos < active_nr &&
873 !strcmp(path, active_cache[pos]->name)) {
874 /*
875 * If stage #0, it is definitely tracked.
876 * If it has stage #2 then it was tracked
877 * before this merge started. All other
878 * cases the path was not tracked.
879 */
880 switch (ce_stage(active_cache[pos])) {
881 case 0:
882 case 2:
883 return 0;
884 }
885 pos++;
886 }
887 return file_exists(path);
888 }
889
890 static int was_dirty(struct merge_options *o, const char *path)
891 {
892 struct cache_entry *ce;
893 int dirty = 1;
894
895 if (o->call_depth || !was_tracked(o, path))
896 return !dirty;
897
898 ce = index_file_exists(o->unpack_opts.src_index,
899 path, strlen(path), ignore_case);
900 dirty = verify_uptodate(ce, &o->unpack_opts) != 0;
901 return dirty;
902 }
903
904 static int make_room_for_path(struct merge_options *o, const char *path)
905 {
906 int status, i;
907 const char *msg = _("failed to create path '%s'%s");
908
909 /* Unlink any D/F conflict files that are in the way */
910 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
911 const char *df_path = o->df_conflict_file_set.items[i].string;
912 size_t pathlen = strlen(path);
913 size_t df_pathlen = strlen(df_path);
914 if (df_pathlen < pathlen &&
915 path[df_pathlen] == '/' &&
916 strncmp(path, df_path, df_pathlen) == 0) {
917 output(o, 3,
918 _("Removing %s to make room for subdirectory\n"),
919 df_path);
920 unlink(df_path);
921 unsorted_string_list_delete_item(&o->df_conflict_file_set,
922 i, 0);
923 break;
924 }
925 }
926
927 /* Make sure leading directories are created */
928 status = safe_create_leading_directories_const(path);
929 if (status) {
930 if (status == SCLD_EXISTS)
931 /* something else exists */
932 return err(o, msg, path, _(": perhaps a D/F conflict?"));
933 return err(o, msg, path, "");
934 }
935
936 /*
937 * Do not unlink a file in the work tree if we are not
938 * tracking it.
939 */
940 if (would_lose_untracked(path))
941 return err(o, _("refusing to lose untracked file at '%s'"),
942 path);
943
944 /* Successful unlink is good.. */
945 if (!unlink(path))
946 return 0;
947 /* .. and so is no existing file */
948 if (errno == ENOENT)
949 return 0;
950 /* .. but not some other error (who really cares what?) */
951 return err(o, msg, path, _(": perhaps a D/F conflict?"));
952 }
953
954 static int update_file_flags(struct merge_options *o,
955 const struct object_id *oid,
956 unsigned mode,
957 const char *path,
958 int update_cache,
959 int update_wd)
960 {
961 int ret = 0;
962
963 if (o->call_depth)
964 update_wd = 0;
965
966 if (update_wd) {
967 enum object_type type;
968 void *buf;
969 unsigned long size;
970
971 if (S_ISGITLINK(mode)) {
972 /*
973 * We may later decide to recursively descend into
974 * the submodule directory and update its index
975 * and/or work tree, but we do not do that now.
976 */
977 update_wd = 0;
978 goto update_index;
979 }
980
981 buf = read_object_file(oid, &type, &size);
982 if (!buf)
983 return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path);
984 if (type != OBJ_BLOB) {
985 ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path);
986 goto free_buf;
987 }
988 if (S_ISREG(mode)) {
989 struct strbuf strbuf = STRBUF_INIT;
990 if (convert_to_working_tree(&the_index, path, buf, size, &strbuf)) {
991 free(buf);
992 size = strbuf.len;
993 buf = strbuf_detach(&strbuf, NULL);
994 }
995 }
996
997 if (make_room_for_path(o, path) < 0) {
998 update_wd = 0;
999 goto free_buf;
1000 }
1001 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
1002 int fd;
1003 if (mode & 0100)
1004 mode = 0777;
1005 else
1006 mode = 0666;
1007 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
1008 if (fd < 0) {
1009 ret = err(o, _("failed to open '%s': %s"),
1010 path, strerror(errno));
1011 goto free_buf;
1012 }
1013 write_in_full(fd, buf, size);
1014 close(fd);
1015 } else if (S_ISLNK(mode)) {
1016 char *lnk = xmemdupz(buf, size);
1017 safe_create_leading_directories_const(path);
1018 unlink(path);
1019 if (symlink(lnk, path))
1020 ret = err(o, _("failed to symlink '%s': %s"),
1021 path, strerror(errno));
1022 free(lnk);
1023 } else
1024 ret = err(o,
1025 _("do not know what to do with %06o %s '%s'"),
1026 mode, oid_to_hex(oid), path);
1027 free_buf:
1028 free(buf);
1029 }
1030 update_index:
1031 if (!ret && update_cache)
1032 if (add_cacheinfo(o, mode, oid, path, 0, update_wd,
1033 ADD_CACHE_OK_TO_ADD))
1034 return -1;
1035 return ret;
1036 }
1037
1038 static int update_file(struct merge_options *o,
1039 int clean,
1040 const struct object_id *oid,
1041 unsigned mode,
1042 const char *path)
1043 {
1044 return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth);
1045 }
1046
1047 /* Low level file merging, update and removal */
1048
1049 struct merge_file_info {
1050 struct object_id oid;
1051 unsigned mode;
1052 unsigned clean:1,
1053 merge:1;
1054 };
1055
1056 static int merge_3way(struct merge_options *o,
1057 mmbuffer_t *result_buf,
1058 const struct diff_filespec *one,
1059 const struct diff_filespec *a,
1060 const struct diff_filespec *b,
1061 const char *branch1,
1062 const char *branch2)
1063 {
1064 mmfile_t orig, src1, src2;
1065 struct ll_merge_options ll_opts = {0};
1066 char *base_name, *name1, *name2;
1067 int merge_status;
1068
1069 ll_opts.renormalize = o->renormalize;
1070 ll_opts.xdl_opts = o->xdl_opts;
1071
1072 if (o->call_depth) {
1073 ll_opts.virtual_ancestor = 1;
1074 ll_opts.variant = 0;
1075 } else {
1076 switch (o->recursive_variant) {
1077 case MERGE_RECURSIVE_OURS:
1078 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
1079 break;
1080 case MERGE_RECURSIVE_THEIRS:
1081 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
1082 break;
1083 default:
1084 ll_opts.variant = 0;
1085 break;
1086 }
1087 }
1088
1089 if (strcmp(a->path, b->path) ||
1090 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
1091 base_name = o->ancestor == NULL ? NULL :
1092 mkpathdup("%s:%s", o->ancestor, one->path);
1093 name1 = mkpathdup("%s:%s", branch1, a->path);
1094 name2 = mkpathdup("%s:%s", branch2, b->path);
1095 } else {
1096 base_name = o->ancestor == NULL ? NULL :
1097 mkpathdup("%s", o->ancestor);
1098 name1 = mkpathdup("%s", branch1);
1099 name2 = mkpathdup("%s", branch2);
1100 }
1101
1102 read_mmblob(&orig, &one->oid);
1103 read_mmblob(&src1, &a->oid);
1104 read_mmblob(&src2, &b->oid);
1105
1106 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
1107 &src1, name1, &src2, name2,
1108 &the_index, &ll_opts);
1109
1110 free(base_name);
1111 free(name1);
1112 free(name2);
1113 free(orig.ptr);
1114 free(src1.ptr);
1115 free(src2.ptr);
1116 return merge_status;
1117 }
1118
1119 static int find_first_merges(struct object_array *result, const char *path,
1120 struct commit *a, struct commit *b)
1121 {
1122 int i, j;
1123 struct object_array merges = OBJECT_ARRAY_INIT;
1124 struct commit *commit;
1125 int contains_another;
1126
1127 char merged_revision[42];
1128 const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1129 "--all", merged_revision, NULL };
1130 struct rev_info revs;
1131 struct setup_revision_opt rev_opts;
1132
1133 memset(result, 0, sizeof(struct object_array));
1134 memset(&rev_opts, 0, sizeof(rev_opts));
1135
1136 /* get all revisions that merge commit a */
1137 xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1138 oid_to_hex(&a->object.oid));
1139 repo_init_revisions(the_repository, &revs, NULL);
1140 rev_opts.submodule = path;
1141 /* FIXME: can't handle linked worktrees in submodules yet */
1142 revs.single_worktree = path != NULL;
1143 setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1144
1145 /* save all revisions from the above list that contain b */
1146 if (prepare_revision_walk(&revs))
1147 die("revision walk setup failed");
1148 while ((commit = get_revision(&revs)) != NULL) {
1149 struct object *o = &(commit->object);
1150 if (in_merge_bases(b, commit))
1151 add_object_array(o, NULL, &merges);
1152 }
1153 reset_revision_walk();
1154
1155 /* Now we've got all merges that contain a and b. Prune all
1156 * merges that contain another found merge and save them in
1157 * result.
1158 */
1159 for (i = 0; i < merges.nr; i++) {
1160 struct commit *m1 = (struct commit *) merges.objects[i].item;
1161
1162 contains_another = 0;
1163 for (j = 0; j < merges.nr; j++) {
1164 struct commit *m2 = (struct commit *) merges.objects[j].item;
1165 if (i != j && in_merge_bases(m2, m1)) {
1166 contains_another = 1;
1167 break;
1168 }
1169 }
1170
1171 if (!contains_another)
1172 add_object_array(merges.objects[i].item, NULL, result);
1173 }
1174
1175 object_array_clear(&merges);
1176 return result->nr;
1177 }
1178
1179 static void print_commit(struct commit *commit)
1180 {
1181 struct strbuf sb = STRBUF_INIT;
1182 struct pretty_print_context ctx = {0};
1183 ctx.date_mode.type = DATE_NORMAL;
1184 format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1185 fprintf(stderr, "%s\n", sb.buf);
1186 strbuf_release(&sb);
1187 }
1188
1189 static int merge_submodule(struct merge_options *o,
1190 struct object_id *result, const char *path,
1191 const struct object_id *base, const struct object_id *a,
1192 const struct object_id *b)
1193 {
1194 struct commit *commit_base, *commit_a, *commit_b;
1195 int parent_count;
1196 struct object_array merges;
1197
1198 int i;
1199 int search = !o->call_depth;
1200
1201 /* store a in result in case we fail */
1202 oidcpy(result, a);
1203
1204 /* we can not handle deletion conflicts */
1205 if (is_null_oid(base))
1206 return 0;
1207 if (is_null_oid(a))
1208 return 0;
1209 if (is_null_oid(b))
1210 return 0;
1211
1212 if (add_submodule_odb(path)) {
1213 output(o, 1, _("Failed to merge submodule %s (not checked out)"), path);
1214 return 0;
1215 }
1216
1217 if (!(commit_base = lookup_commit_reference(the_repository, base)) ||
1218 !(commit_a = lookup_commit_reference(the_repository, a)) ||
1219 !(commit_b = lookup_commit_reference(the_repository, b))) {
1220 output(o, 1, _("Failed to merge submodule %s (commits not present)"), path);
1221 return 0;
1222 }
1223
1224 /* check whether both changes are forward */
1225 if (!in_merge_bases(commit_base, commit_a) ||
1226 !in_merge_bases(commit_base, commit_b)) {
1227 output(o, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
1228 return 0;
1229 }
1230
1231 /* Case #1: a is contained in b or vice versa */
1232 if (in_merge_bases(commit_a, commit_b)) {
1233 oidcpy(result, b);
1234 if (show(o, 3)) {
1235 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1236 output_commit_title(o, commit_b);
1237 } else if (show(o, 2))
1238 output(o, 2, _("Fast-forwarding submodule %s"), path);
1239 else
1240 ; /* no output */
1241
1242 return 1;
1243 }
1244 if (in_merge_bases(commit_b, commit_a)) {
1245 oidcpy(result, a);
1246 if (show(o, 3)) {
1247 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1248 output_commit_title(o, commit_a);
1249 } else if (show(o, 2))
1250 output(o, 2, _("Fast-forwarding submodule %s"), path);
1251 else
1252 ; /* no output */
1253
1254 return 1;
1255 }
1256
1257 /*
1258 * Case #2: There are one or more merges that contain a and b in
1259 * the submodule. If there is only one, then present it as a
1260 * suggestion to the user, but leave it marked unmerged so the
1261 * user needs to confirm the resolution.
1262 */
1263
1264 /* Skip the search if makes no sense to the calling context. */
1265 if (!search)
1266 return 0;
1267
1268 /* find commit which merges them */
1269 parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1270 switch (parent_count) {
1271 case 0:
1272 output(o, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
1273 break;
1274
1275 case 1:
1276 output(o, 1, _("Failed to merge submodule %s (not fast-forward)"), path);
1277 output(o, 2, _("Found a possible merge resolution for the submodule:\n"));
1278 print_commit((struct commit *) merges.objects[0].item);
1279 output(o, 2, _(
1280 "If this is correct simply add it to the index "
1281 "for example\n"
1282 "by using:\n\n"
1283 " git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1284 "which will accept this suggestion.\n"),
1285 oid_to_hex(&merges.objects[0].item->oid), path);
1286 break;
1287
1288 default:
1289 output(o, 1, _("Failed to merge submodule %s (multiple merges found)"), path);
1290 for (i = 0; i < merges.nr; i++)
1291 print_commit((struct commit *) merges.objects[i].item);
1292 }
1293
1294 object_array_clear(&merges);
1295 return 0;
1296 }
1297
1298 static int merge_mode_and_contents(struct merge_options *o,
1299 const struct diff_filespec *one,
1300 const struct diff_filespec *a,
1301 const struct diff_filespec *b,
1302 const char *filename,
1303 const char *branch1,
1304 const char *branch2,
1305 struct merge_file_info *result)
1306 {
1307 if (o->branch1 != branch1) {
1308 /*
1309 * It's weird getting a reverse merge with HEAD on the bottom
1310 * side of the conflict markers and the other branch on the
1311 * top. Fix that.
1312 */
1313 return merge_mode_and_contents(o, one, b, a,
1314 filename,
1315 branch2, branch1, result);
1316 }
1317
1318 result->merge = 0;
1319 result->clean = 1;
1320
1321 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
1322 result->clean = 0;
1323 if (S_ISREG(a->mode)) {
1324 result->mode = a->mode;
1325 oidcpy(&result->oid, &a->oid);
1326 } else {
1327 result->mode = b->mode;
1328 oidcpy(&result->oid, &b->oid);
1329 }
1330 } else {
1331 if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid))
1332 result->merge = 1;
1333
1334 /*
1335 * Merge modes
1336 */
1337 if (a->mode == b->mode || a->mode == one->mode)
1338 result->mode = b->mode;
1339 else {
1340 result->mode = a->mode;
1341 if (b->mode != one->mode) {
1342 result->clean = 0;
1343 result->merge = 1;
1344 }
1345 }
1346
1347 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid))
1348 oidcpy(&result->oid, &b->oid);
1349 else if (oid_eq(&b->oid, &one->oid))
1350 oidcpy(&result->oid, &a->oid);
1351 else if (S_ISREG(a->mode)) {
1352 mmbuffer_t result_buf;
1353 int ret = 0, merge_status;
1354
1355 merge_status = merge_3way(o, &result_buf, one, a, b,
1356 branch1, branch2);
1357
1358 if ((merge_status < 0) || !result_buf.ptr)
1359 ret = err(o, _("Failed to execute internal merge"));
1360
1361 if (!ret &&
1362 write_object_file(result_buf.ptr, result_buf.size,
1363 blob_type, &result->oid))
1364 ret = err(o, _("Unable to add %s to database"),
1365 a->path);
1366
1367 free(result_buf.ptr);
1368 if (ret)
1369 return ret;
1370 result->clean = (merge_status == 0);
1371 } else if (S_ISGITLINK(a->mode)) {
1372 result->clean = merge_submodule(o, &result->oid,
1373 one->path,
1374 &one->oid,
1375 &a->oid,
1376 &b->oid);
1377 } else if (S_ISLNK(a->mode)) {
1378 switch (o->recursive_variant) {
1379 case MERGE_RECURSIVE_NORMAL:
1380 oidcpy(&result->oid, &a->oid);
1381 if (!oid_eq(&a->oid, &b->oid))
1382 result->clean = 0;
1383 break;
1384 case MERGE_RECURSIVE_OURS:
1385 oidcpy(&result->oid, &a->oid);
1386 break;
1387 case MERGE_RECURSIVE_THEIRS:
1388 oidcpy(&result->oid, &b->oid);
1389 break;
1390 }
1391 } else
1392 BUG("unsupported object type in the tree");
1393 }
1394
1395 if (result->merge)
1396 output(o, 2, _("Auto-merging %s"), filename);
1397
1398 return 0;
1399 }
1400
1401 static int handle_rename_via_dir(struct merge_options *o,
1402 struct diff_filepair *pair,
1403 const char *rename_branch,
1404 const char *other_branch)
1405 {
1406 /*
1407 * Handle file adds that need to be renamed due to directory rename
1408 * detection. This differs from handle_rename_normal, because
1409 * there is no content merge to do; just move the file into the
1410 * desired final location.
1411 */
1412 const struct diff_filespec *dest = pair->two;
1413
1414 if (!o->call_depth && would_lose_untracked(dest->path)) {
1415 char *alt_path = unique_path(o, dest->path, rename_branch);
1416
1417 output(o, 1, _("Error: Refusing to lose untracked file at %s; "
1418 "writing to %s instead."),
1419 dest->path, alt_path);
1420 /*
1421 * Write the file in worktree at alt_path, but not in the
1422 * index. Instead, write to dest->path for the index but
1423 * only at the higher appropriate stage.
1424 */
1425 if (update_file(o, 0, &dest->oid, dest->mode, alt_path))
1426 return -1;
1427 free(alt_path);
1428 return update_stages(o, dest->path, NULL,
1429 rename_branch == o->branch1 ? dest : NULL,
1430 rename_branch == o->branch1 ? NULL : dest);
1431 }
1432
1433 /* Update dest->path both in index and in worktree */
1434 if (update_file(o, 1, &dest->oid, dest->mode, dest->path))
1435 return -1;
1436 return 0;
1437 }
1438
1439 static int handle_change_delete(struct merge_options *o,
1440 const char *path, const char *old_path,
1441 const struct object_id *o_oid, int o_mode,
1442 const struct object_id *changed_oid,
1443 int changed_mode,
1444 const char *change_branch,
1445 const char *delete_branch,
1446 const char *change, const char *change_past)
1447 {
1448 char *alt_path = NULL;
1449 const char *update_path = path;
1450 int ret = 0;
1451
1452 if (dir_in_way(path, !o->call_depth, 0) ||
1453 (!o->call_depth && would_lose_untracked(path))) {
1454 update_path = alt_path = unique_path(o, path, change_branch);
1455 }
1456
1457 if (o->call_depth) {
1458 /*
1459 * We cannot arbitrarily accept either a_sha or b_sha as
1460 * correct; since there is no true "middle point" between
1461 * them, simply reuse the base version for virtual merge base.
1462 */
1463 ret = remove_file_from_cache(path);
1464 if (!ret)
1465 ret = update_file(o, 0, o_oid, o_mode, update_path);
1466 } else {
1467 /*
1468 * Despite the four nearly duplicate messages and argument
1469 * lists below and the ugliness of the nested if-statements,
1470 * having complete messages makes the job easier for
1471 * translators.
1472 *
1473 * The slight variance among the cases is due to the fact
1474 * that:
1475 * 1) directory/file conflicts (in effect if
1476 * !alt_path) could cause us to need to write the
1477 * file to a different path.
1478 * 2) renames (in effect if !old_path) could mean that
1479 * there are two names for the path that the user
1480 * may know the file by.
1481 */
1482 if (!alt_path) {
1483 if (!old_path) {
1484 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1485 "and %s in %s. Version %s of %s left in tree."),
1486 change, path, delete_branch, change_past,
1487 change_branch, change_branch, path);
1488 } else {
1489 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1490 "and %s to %s in %s. Version %s of %s left in tree."),
1491 change, old_path, delete_branch, change_past, path,
1492 change_branch, change_branch, path);
1493 }
1494 } else {
1495 if (!old_path) {
1496 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1497 "and %s in %s. Version %s of %s left in tree at %s."),
1498 change, path, delete_branch, change_past,
1499 change_branch, change_branch, path, alt_path);
1500 } else {
1501 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1502 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1503 change, old_path, delete_branch, change_past, path,
1504 change_branch, change_branch, path, alt_path);
1505 }
1506 }
1507 /*
1508 * No need to call update_file() on path when change_branch ==
1509 * o->branch1 && !alt_path, since that would needlessly touch
1510 * path. We could call update_file_flags() with update_cache=0
1511 * and update_wd=0, but that's a no-op.
1512 */
1513 if (change_branch != o->branch1 || alt_path)
1514 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1515 }
1516 free(alt_path);
1517
1518 return ret;
1519 }
1520
1521 static int handle_rename_delete(struct merge_options *o,
1522 struct diff_filepair *pair,
1523 const char *rename_branch,
1524 const char *delete_branch)
1525 {
1526 const struct diff_filespec *orig = pair->one;
1527 const struct diff_filespec *dest = pair->two;
1528
1529 if (handle_change_delete(o,
1530 o->call_depth ? orig->path : dest->path,
1531 o->call_depth ? NULL : orig->path,
1532 &orig->oid, orig->mode,
1533 &dest->oid, dest->mode,
1534 rename_branch, delete_branch,
1535 _("rename"), _("renamed")))
1536 return -1;
1537
1538 if (o->call_depth)
1539 return remove_file_from_cache(dest->path);
1540 else
1541 return update_stages(o, dest->path, NULL,
1542 rename_branch == o->branch1 ? dest : NULL,
1543 rename_branch == o->branch1 ? NULL : dest);
1544 }
1545
1546 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1547 struct stage_data *entry,
1548 int stage)
1549 {
1550 struct object_id *oid = &entry->stages[stage].oid;
1551 unsigned mode = entry->stages[stage].mode;
1552 if (mode == 0 || is_null_oid(oid))
1553 return NULL;
1554 oidcpy(&target->oid, oid);
1555 target->mode = mode;
1556 return target;
1557 }
1558
1559 static int handle_file(struct merge_options *o,
1560 struct diff_filespec *rename,
1561 int stage,
1562 struct rename_conflict_info *ci)
1563 {
1564 char *dst_name = rename->path;
1565 struct stage_data *dst_entry;
1566 const char *cur_branch, *other_branch;
1567 struct diff_filespec other;
1568 struct diff_filespec *add;
1569 int ret;
1570
1571 if (stage == 2) {
1572 dst_entry = ci->dst_entry1;
1573 cur_branch = ci->branch1;
1574 other_branch = ci->branch2;
1575 } else {
1576 dst_entry = ci->dst_entry2;
1577 cur_branch = ci->branch2;
1578 other_branch = ci->branch1;
1579 }
1580
1581 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1582 if (add) {
1583 int ren_src_was_dirty = was_dirty(o, rename->path);
1584 char *add_name = unique_path(o, rename->path, other_branch);
1585 if (update_file(o, 0, &add->oid, add->mode, add_name))
1586 return -1;
1587
1588 if (ren_src_was_dirty) {
1589 output(o, 1, _("Refusing to lose dirty file at %s"),
1590 rename->path);
1591 }
1592 /*
1593 * Because the double negatives somehow keep confusing me...
1594 * 1) update_wd iff !ren_src_was_dirty.
1595 * 2) no_wd iff !update_wd
1596 * 3) so, no_wd == !!ren_src_was_dirty == ren_src_was_dirty
1597 */
1598 remove_file(o, 0, rename->path, ren_src_was_dirty);
1599 dst_name = unique_path(o, rename->path, cur_branch);
1600 } else {
1601 if (dir_in_way(rename->path, !o->call_depth, 0)) {
1602 dst_name = unique_path(o, rename->path, cur_branch);
1603 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1604 rename->path, other_branch, dst_name);
1605 } else if (!o->call_depth &&
1606 would_lose_untracked(rename->path)) {
1607 dst_name = unique_path(o, rename->path, cur_branch);
1608 output(o, 1, _("Refusing to lose untracked file at %s; "
1609 "adding as %s instead"),
1610 rename->path, dst_name);
1611 }
1612 }
1613 if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name)))
1614 ; /* fall through, do allow dst_name to be released */
1615 else if (stage == 2)
1616 ret = update_stages(o, rename->path, NULL, rename, add);
1617 else
1618 ret = update_stages(o, rename->path, NULL, add, rename);
1619
1620 if (dst_name != rename->path)
1621 free(dst_name);
1622
1623 return ret;
1624 }
1625
1626 static int handle_rename_rename_1to2(struct merge_options *o,
1627 struct rename_conflict_info *ci)
1628 {
1629 /* One file was renamed in both branches, but to different names. */
1630 struct diff_filespec *one = ci->pair1->one;
1631 struct diff_filespec *a = ci->pair1->two;
1632 struct diff_filespec *b = ci->pair2->two;
1633
1634 output(o, 1, _("CONFLICT (rename/rename): "
1635 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1636 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1637 one->path, a->path, ci->branch1,
1638 one->path, b->path, ci->branch2,
1639 o->call_depth ? _(" (left unresolved)") : "");
1640 if (o->call_depth) {
1641 struct merge_file_info mfi;
1642 struct diff_filespec other;
1643 struct diff_filespec *add;
1644 if (merge_mode_and_contents(o, one, a, b, one->path,
1645 ci->branch1, ci->branch2, &mfi))
1646 return -1;
1647
1648 /*
1649 * FIXME: For rename/add-source conflicts (if we could detect
1650 * such), this is wrong. We should instead find a unique
1651 * pathname and then either rename the add-source file to that
1652 * unique path, or use that unique path instead of src here.
1653 */
1654 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1655 return -1;
1656
1657 /*
1658 * Above, we put the merged content at the merge-base's
1659 * path. Now we usually need to delete both a->path and
1660 * b->path. However, the rename on each side of the merge
1661 * could also be involved in a rename/add conflict. In
1662 * such cases, we should keep the added file around,
1663 * resolving the conflict at that path in its favor.
1664 */
1665 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1666 if (add) {
1667 if (update_file(o, 0, &add->oid, add->mode, a->path))
1668 return -1;
1669 }
1670 else
1671 remove_file_from_cache(a->path);
1672 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1673 if (add) {
1674 if (update_file(o, 0, &add->oid, add->mode, b->path))
1675 return -1;
1676 }
1677 else
1678 remove_file_from_cache(b->path);
1679 } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci))
1680 return -1;
1681
1682 return 0;
1683 }
1684
1685 static int handle_rename_rename_2to1(struct merge_options *o,
1686 struct rename_conflict_info *ci)
1687 {
1688 /* Two files, a & b, were renamed to the same thing, c. */
1689 struct diff_filespec *a = ci->pair1->one;
1690 struct diff_filespec *b = ci->pair2->one;
1691 struct diff_filespec *c1 = ci->pair1->two;
1692 struct diff_filespec *c2 = ci->pair2->two;
1693 char *path = c1->path; /* == c2->path */
1694 char *path_side_1_desc;
1695 char *path_side_2_desc;
1696 struct merge_file_info mfi_c1;
1697 struct merge_file_info mfi_c2;
1698 int ret;
1699
1700 output(o, 1, _("CONFLICT (rename/rename): "
1701 "Rename %s->%s in %s. "
1702 "Rename %s->%s in %s"),
1703 a->path, c1->path, ci->branch1,
1704 b->path, c2->path, ci->branch2);
1705
1706 remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path));
1707 remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path));
1708
1709 path_side_1_desc = xstrfmt("version of %s from %s", path, a->path);
1710 path_side_2_desc = xstrfmt("version of %s from %s", path, b->path);
1711 if (merge_mode_and_contents(o, a, c1, &ci->ren1_other, path_side_1_desc,
1712 o->branch1, o->branch2, &mfi_c1) ||
1713 merge_mode_and_contents(o, b, &ci->ren2_other, c2, path_side_2_desc,
1714 o->branch1, o->branch2, &mfi_c2))
1715 return -1;
1716 free(path_side_1_desc);
1717 free(path_side_2_desc);
1718
1719 if (o->call_depth) {
1720 /*
1721 * If mfi_c1.clean && mfi_c2.clean, then it might make
1722 * sense to do a two-way merge of those results. But, I
1723 * think in all cases, it makes sense to have the virtual
1724 * merge base just undo the renames; they can be detected
1725 * again later for the non-recursive merge.
1726 */
1727 remove_file(o, 0, path, 0);
1728 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path);
1729 if (!ret)
1730 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1731 b->path);
1732 } else {
1733 char *new_path1 = unique_path(o, path, ci->branch1);
1734 char *new_path2 = unique_path(o, path, ci->branch2);
1735 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1736 a->path, new_path1, b->path, new_path2);
1737 if (was_dirty(o, path))
1738 output(o, 1, _("Refusing to lose dirty file at %s"),
1739 path);
1740 else if (would_lose_untracked(path))
1741 /*
1742 * Only way we get here is if both renames were from
1743 * a directory rename AND user had an untracked file
1744 * at the location where both files end up after the
1745 * two directory renames. See testcase 10d of t6043.
1746 */
1747 output(o, 1, _("Refusing to lose untracked file at "
1748 "%s, even though it's in the way."),
1749 path);
1750 else
1751 remove_file(o, 0, path, 0);
1752 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1);
1753 if (!ret)
1754 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1755 new_path2);
1756 /*
1757 * unpack_trees() actually populates the index for us for
1758 * "normal" rename/rename(2to1) situtations so that the
1759 * correct entries are at the higher stages, which would
1760 * make the call below to update_stages_for_stage_data
1761 * unnecessary. However, if either of the renames came
1762 * from a directory rename, then unpack_trees() will not
1763 * have gotten the right data loaded into the index, so we
1764 * need to do so now. (While it'd be tempting to move this
1765 * call to update_stages_for_stage_data() to
1766 * apply_directory_rename_modifications(), that would break
1767 * our intermediate calls to would_lose_untracked() since
1768 * those rely on the current in-memory index. See also the
1769 * big "NOTE" in update_stages()).
1770 */
1771 if (update_stages_for_stage_data(o, path, ci->dst_entry1))
1772 ret = -1;
1773
1774 free(new_path2);
1775 free(new_path1);
1776 }
1777
1778 return ret;
1779 }
1780
1781 /*
1782 * Get the diff_filepairs changed between o_tree and tree.
1783 */
1784 static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
1785 struct tree *o_tree,
1786 struct tree *tree)
1787 {
1788 struct diff_queue_struct *ret;
1789 struct diff_options opts;
1790
1791 repo_diff_setup(the_repository, &opts);
1792 opts.flags.recursive = 1;
1793 opts.flags.rename_empty = 0;
1794 opts.detect_rename = merge_detect_rename(o);
1795 /*
1796 * We do not have logic to handle the detection of copies. In
1797 * fact, it may not even make sense to add such logic: would we
1798 * really want a change to a base file to be propagated through
1799 * multiple other files by a merge?
1800 */
1801 if (opts.detect_rename > DIFF_DETECT_RENAME)
1802 opts.detect_rename = DIFF_DETECT_RENAME;
1803 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
1804 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
1805 1000;
1806 opts.rename_score = o->rename_score;
1807 opts.show_rename_progress = o->show_rename_progress;
1808 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1809 diff_setup_done(&opts);
1810 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1811 diffcore_std(&opts);
1812 if (opts.needed_rename_limit > o->needed_rename_limit)
1813 o->needed_rename_limit = opts.needed_rename_limit;
1814
1815 ret = xmalloc(sizeof(*ret));
1816 *ret = diff_queued_diff;
1817
1818 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1819 diff_queued_diff.nr = 0;
1820 diff_queued_diff.queue = NULL;
1821 diff_flush(&opts);
1822 return ret;
1823 }
1824
1825 static int tree_has_path(struct tree *tree, const char *path)
1826 {
1827 struct object_id hashy;
1828 unsigned int mode_o;
1829
1830 return !get_tree_entry(&tree->object.oid, path,
1831 &hashy, &mode_o);
1832 }
1833
1834 /*
1835 * Return a new string that replaces the beginning portion (which matches
1836 * entry->dir), with entry->new_dir. In perl-speak:
1837 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1838 * NOTE:
1839 * Caller must ensure that old_path starts with entry->dir + '/'.
1840 */
1841 static char *apply_dir_rename(struct dir_rename_entry *entry,
1842 const char *old_path)
1843 {
1844 struct strbuf new_path = STRBUF_INIT;
1845 int oldlen, newlen;
1846
1847 if (entry->non_unique_new_dir)
1848 return NULL;
1849
1850 oldlen = strlen(entry->dir);
1851 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1852 strbuf_grow(&new_path, newlen);
1853 strbuf_addbuf(&new_path, &entry->new_dir);
1854 strbuf_addstr(&new_path, &old_path[oldlen]);
1855
1856 return strbuf_detach(&new_path, NULL);
1857 }
1858
1859 static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1860 char **old_dir, char **new_dir)
1861 {
1862 char *end_of_old, *end_of_new;
1863 int old_len, new_len;
1864
1865 *old_dir = NULL;
1866 *new_dir = NULL;
1867
1868 /*
1869 * For
1870 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1871 * the "e/foo.c" part is the same, we just want to know that
1872 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1873 * so, for this example, this function returns "a/b/c/d" in
1874 * *old_dir and "a/b/some/thing/else" in *new_dir.
1875 *
1876 * Also, if the basename of the file changed, we don't care. We
1877 * want to know which portion of the directory, if any, changed.
1878 */
1879 end_of_old = strrchr(old_path, '/');
1880 end_of_new = strrchr(new_path, '/');
1881
1882 if (end_of_old == NULL || end_of_new == NULL)
1883 return;
1884 while (*--end_of_new == *--end_of_old &&
1885 end_of_old != old_path &&
1886 end_of_new != new_path)
1887 ; /* Do nothing; all in the while loop */
1888 /*
1889 * We've found the first non-matching character in the directory
1890 * paths. That means the current directory we were comparing
1891 * represents the rename. Move end_of_old and end_of_new back
1892 * to the full directory name.
1893 */
1894 if (*end_of_old == '/')
1895 end_of_old++;
1896 if (*end_of_old != '/')
1897 end_of_new++;
1898 end_of_old = strchr(end_of_old, '/');
1899 end_of_new = strchr(end_of_new, '/');
1900
1901 /*
1902 * It may have been the case that old_path and new_path were the same
1903 * directory all along. Don't claim a rename if they're the same.
1904 */
1905 old_len = end_of_old - old_path;
1906 new_len = end_of_new - new_path;
1907
1908 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
1909 *old_dir = xstrndup(old_path, old_len);
1910 *new_dir = xstrndup(new_path, new_len);
1911 }
1912 }
1913
1914 static void remove_hashmap_entries(struct hashmap *dir_renames,
1915 struct string_list *items_to_remove)
1916 {
1917 int i;
1918 struct dir_rename_entry *entry;
1919
1920 for (i = 0; i < items_to_remove->nr; i++) {
1921 entry = items_to_remove->items[i].util;
1922 hashmap_remove(dir_renames, entry, NULL);
1923 }
1924 string_list_clear(items_to_remove, 0);
1925 }
1926
1927 /*
1928 * See if there is a directory rename for path, and if there are any file
1929 * level conflicts for the renamed location. If there is a rename and
1930 * there are no conflicts, return the new name. Otherwise, return NULL.
1931 */
1932 static char *handle_path_level_conflicts(struct merge_options *o,
1933 const char *path,
1934 struct dir_rename_entry *entry,
1935 struct hashmap *collisions,
1936 struct tree *tree)
1937 {
1938 char *new_path = NULL;
1939 struct collision_entry *collision_ent;
1940 int clean = 1;
1941 struct strbuf collision_paths = STRBUF_INIT;
1942
1943 /*
1944 * entry has the mapping of old directory name to new directory name
1945 * that we want to apply to path.
1946 */
1947 new_path = apply_dir_rename(entry, path);
1948
1949 if (!new_path) {
1950 /* This should only happen when entry->non_unique_new_dir set */
1951 if (!entry->non_unique_new_dir)
1952 BUG("entry->non_unqiue_dir not set and !new_path");
1953 output(o, 1, _("CONFLICT (directory rename split): "
1954 "Unclear where to place %s because directory "
1955 "%s was renamed to multiple other directories, "
1956 "with no destination getting a majority of the "
1957 "files."),
1958 path, entry->dir);
1959 clean = 0;
1960 return NULL;
1961 }
1962
1963 /*
1964 * The caller needs to have ensured that it has pre-populated
1965 * collisions with all paths that map to new_path. Do a quick check
1966 * to ensure that's the case.
1967 */
1968 collision_ent = collision_find_entry(collisions, new_path);
1969 if (collision_ent == NULL)
1970 BUG("collision_ent is NULL");
1971
1972 /*
1973 * Check for one-sided add/add/.../add conflicts, i.e.
1974 * where implicit renames from the other side doing
1975 * directory rename(s) can affect this side of history
1976 * to put multiple paths into the same location. Warn
1977 * and bail on directory renames for such paths.
1978 */
1979 if (collision_ent->reported_already) {
1980 clean = 0;
1981 } else if (tree_has_path(tree, new_path)) {
1982 collision_ent->reported_already = 1;
1983 strbuf_add_separated_string_list(&collision_paths, ", ",
1984 &collision_ent->source_files);
1985 output(o, 1, _("CONFLICT (implicit dir rename): Existing "
1986 "file/dir at %s in the way of implicit "
1987 "directory rename(s) putting the following "
1988 "path(s) there: %s."),
1989 new_path, collision_paths.buf);
1990 clean = 0;
1991 } else if (collision_ent->source_files.nr > 1) {
1992 collision_ent->reported_already = 1;
1993 strbuf_add_separated_string_list(&collision_paths, ", ",
1994 &collision_ent->source_files);
1995 output(o, 1, _("CONFLICT (implicit dir rename): Cannot map "
1996 "more than one path to %s; implicit directory "
1997 "renames tried to put these paths there: %s"),
1998 new_path, collision_paths.buf);
1999 clean = 0;
2000 }
2001
2002 /* Free memory we no longer need */
2003 strbuf_release(&collision_paths);
2004 if (!clean && new_path) {
2005 free(new_path);
2006 return NULL;
2007 }
2008
2009 return new_path;
2010 }
2011
2012 /*
2013 * There are a couple things we want to do at the directory level:
2014 * 1. Check for both sides renaming to the same thing, in order to avoid
2015 * implicit renaming of files that should be left in place. (See
2016 * testcase 6b in t6043 for details.)
2017 * 2. Prune directory renames if there are still files left in the
2018 * the original directory. These represent a partial directory rename,
2019 * i.e. a rename where only some of the files within the directory
2020 * were renamed elsewhere. (Technically, this could be done earlier
2021 * in get_directory_renames(), except that would prevent us from
2022 * doing the previous check and thus failing testcase 6b.)
2023 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
2024 * In the future, we could potentially record this info as well and
2025 * omit reporting rename/rename(1to2) conflicts for each path within
2026 * the affected directories, thus cleaning up the merge output.
2027 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
2028 * directory level, because merging directories is fine. If it
2029 * causes conflicts for files within those merged directories, then
2030 * that should be detected at the individual path level.
2031 */
2032 static void handle_directory_level_conflicts(struct merge_options *o,
2033 struct hashmap *dir_re_head,
2034 struct tree *head,
2035 struct hashmap *dir_re_merge,
2036 struct tree *merge)
2037 {
2038 struct hashmap_iter iter;
2039 struct dir_rename_entry *head_ent;
2040 struct dir_rename_entry *merge_ent;
2041
2042 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
2043 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
2044
2045 hashmap_iter_init(dir_re_head, &iter);
2046 while ((head_ent = hashmap_iter_next(&iter))) {
2047 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
2048 if (merge_ent &&
2049 !head_ent->non_unique_new_dir &&
2050 !merge_ent->non_unique_new_dir &&
2051 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
2052 /* 1. Renamed identically; remove it from both sides */
2053 string_list_append(&remove_from_head,
2054 head_ent->dir)->util = head_ent;
2055 strbuf_release(&head_ent->new_dir);
2056 string_list_append(&remove_from_merge,
2057 merge_ent->dir)->util = merge_ent;
2058 strbuf_release(&merge_ent->new_dir);
2059 } else if (tree_has_path(head, head_ent->dir)) {
2060 /* 2. This wasn't a directory rename after all */
2061 string_list_append(&remove_from_head,
2062 head_ent->dir)->util = head_ent;
2063 strbuf_release(&head_ent->new_dir);
2064 }
2065 }
2066
2067 remove_hashmap_entries(dir_re_head, &remove_from_head);
2068 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2069
2070 hashmap_iter_init(dir_re_merge, &iter);
2071 while ((merge_ent = hashmap_iter_next(&iter))) {
2072 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
2073 if (tree_has_path(merge, merge_ent->dir)) {
2074 /* 2. This wasn't a directory rename after all */
2075 string_list_append(&remove_from_merge,
2076 merge_ent->dir)->util = merge_ent;
2077 } else if (head_ent &&
2078 !head_ent->non_unique_new_dir &&
2079 !merge_ent->non_unique_new_dir) {
2080 /* 3. rename/rename(1to2) */
2081 /*
2082 * We can assume it's not rename/rename(1to1) because
2083 * that was case (1), already checked above. So we
2084 * know that head_ent->new_dir and merge_ent->new_dir
2085 * are different strings.
2086 */
2087 output(o, 1, _("CONFLICT (rename/rename): "
2088 "Rename directory %s->%s in %s. "
2089 "Rename directory %s->%s in %s"),
2090 head_ent->dir, head_ent->new_dir.buf, o->branch1,
2091 head_ent->dir, merge_ent->new_dir.buf, o->branch2);
2092 string_list_append(&remove_from_head,
2093 head_ent->dir)->util = head_ent;
2094 strbuf_release(&head_ent->new_dir);
2095 string_list_append(&remove_from_merge,
2096 merge_ent->dir)->util = merge_ent;
2097 strbuf_release(&merge_ent->new_dir);
2098 }
2099 }
2100
2101 remove_hashmap_entries(dir_re_head, &remove_from_head);
2102 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2103 }
2104
2105 static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
2106 struct tree *tree)
2107 {
2108 struct hashmap *dir_renames;
2109 struct hashmap_iter iter;
2110 struct dir_rename_entry *entry;
2111 int i;
2112
2113 /*
2114 * Typically, we think of a directory rename as all files from a
2115 * certain directory being moved to a target directory. However,
2116 * what if someone first moved two files from the original
2117 * directory in one commit, and then renamed the directory
2118 * somewhere else in a later commit? At merge time, we just know
2119 * that files from the original directory went to two different
2120 * places, and that the bulk of them ended up in the same place.
2121 * We want each directory rename to represent where the bulk of the
2122 * files from that directory end up; this function exists to find
2123 * where the bulk of the files went.
2124 *
2125 * The first loop below simply iterates through the list of file
2126 * renames, finding out how often each directory rename pair
2127 * possibility occurs.
2128 */
2129 dir_renames = xmalloc(sizeof(*dir_renames));
2130 dir_rename_init(dir_renames);
2131 for (i = 0; i < pairs->nr; ++i) {
2132 struct string_list_item *item;
2133 int *count;
2134 struct diff_filepair *pair = pairs->queue[i];
2135 char *old_dir, *new_dir;
2136
2137 /* File not part of directory rename if it wasn't renamed */
2138 if (pair->status != 'R')
2139 continue;
2140
2141 get_renamed_dir_portion(pair->one->path, pair->two->path,
2142 &old_dir, &new_dir);
2143 if (!old_dir)
2144 /* Directory didn't change at all; ignore this one. */
2145 continue;
2146
2147 entry = dir_rename_find_entry(dir_renames, old_dir);
2148 if (!entry) {
2149 entry = xmalloc(sizeof(*entry));
2150 dir_rename_entry_init(entry, old_dir);
2151 hashmap_put(dir_renames, entry);
2152 } else {
2153 free(old_dir);
2154 }
2155 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
2156 if (!item) {
2157 item = string_list_insert(&entry->possible_new_dirs,
2158 new_dir);
2159 item->util = xcalloc(1, sizeof(int));
2160 } else {
2161 free(new_dir);
2162 }
2163 count = item->util;
2164 *count += 1;
2165 }
2166
2167 /*
2168 * For each directory with files moved out of it, we find out which
2169 * target directory received the most files so we can declare it to
2170 * be the "winning" target location for the directory rename. This
2171 * winner gets recorded in new_dir. If there is no winner
2172 * (multiple target directories received the same number of files),
2173 * we set non_unique_new_dir. Once we've determined the winner (or
2174 * that there is no winner), we no longer need possible_new_dirs.
2175 */
2176 hashmap_iter_init(dir_renames, &iter);
2177 while ((entry = hashmap_iter_next(&iter))) {
2178 int max = 0;
2179 int bad_max = 0;
2180 char *best = NULL;
2181
2182 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
2183 int *count = entry->possible_new_dirs.items[i].util;
2184
2185 if (*count == max)
2186 bad_max = max;
2187 else if (*count > max) {
2188 max = *count;
2189 best = entry->possible_new_dirs.items[i].string;
2190 }
2191 }
2192 if (bad_max == max)
2193 entry->non_unique_new_dir = 1;
2194 else {
2195 assert(entry->new_dir.len == 0);
2196 strbuf_addstr(&entry->new_dir, best);
2197 }
2198 /*
2199 * The relevant directory sub-portion of the original full
2200 * filepaths were xstrndup'ed before inserting into
2201 * possible_new_dirs, and instead of manually iterating the
2202 * list and free'ing each, just lie and tell
2203 * possible_new_dirs that it did the strdup'ing so that it
2204 * will free them for us.
2205 */
2206 entry->possible_new_dirs.strdup_strings = 1;
2207 string_list_clear(&entry->possible_new_dirs, 1);
2208 }
2209
2210 return dir_renames;
2211 }
2212
2213 static struct dir_rename_entry *check_dir_renamed(const char *path,
2214 struct hashmap *dir_renames)
2215 {
2216 char *temp = xstrdup(path);
2217 char *end;
2218 struct dir_rename_entry *entry = NULL;
2219
2220 while ((end = strrchr(temp, '/'))) {
2221 *end = '\0';
2222 entry = dir_rename_find_entry(dir_renames, temp);
2223 if (entry)
2224 break;
2225 }
2226 free(temp);
2227 return entry;
2228 }
2229
2230 static void compute_collisions(struct hashmap *collisions,
2231 struct hashmap *dir_renames,
2232 struct diff_queue_struct *pairs)
2233 {
2234 int i;
2235
2236 /*
2237 * Multiple files can be mapped to the same path due to directory
2238 * renames done by the other side of history. Since that other
2239 * side of history could have merged multiple directories into one,
2240 * if our side of history added the same file basename to each of
2241 * those directories, then all N of them would get implicitly
2242 * renamed by the directory rename detection into the same path,
2243 * and we'd get an add/add/.../add conflict, and all those adds
2244 * from *this* side of history. This is not representable in the
2245 * index, and users aren't going to easily be able to make sense of
2246 * it. So we need to provide a good warning about what's
2247 * happening, and fall back to no-directory-rename detection
2248 * behavior for those paths.
2249 *
2250 * See testcases 9e and all of section 5 from t6043 for examples.
2251 */
2252 collision_init(collisions);
2253
2254 for (i = 0; i < pairs->nr; ++i) {
2255 struct dir_rename_entry *dir_rename_ent;
2256 struct collision_entry *collision_ent;
2257 char *new_path;
2258 struct diff_filepair *pair = pairs->queue[i];
2259
2260 if (pair->status != 'A' && pair->status != 'R')
2261 continue;
2262 dir_rename_ent = check_dir_renamed(pair->two->path,
2263 dir_renames);
2264 if (!dir_rename_ent)
2265 continue;
2266
2267 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
2268 if (!new_path)
2269 /*
2270 * dir_rename_ent->non_unique_new_path is true, which
2271 * means there is no directory rename for us to use,
2272 * which means it won't cause us any additional
2273 * collisions.
2274 */
2275 continue;
2276 collision_ent = collision_find_entry(collisions, new_path);
2277 if (!collision_ent) {
2278 collision_ent = xcalloc(1,
2279 sizeof(struct collision_entry));
2280 hashmap_entry_init(collision_ent, strhash(new_path));
2281 hashmap_put(collisions, collision_ent);
2282 collision_ent->target_file = new_path;
2283 } else {
2284 free(new_path);
2285 }
2286 string_list_insert(&collision_ent->source_files,
2287 pair->two->path);
2288 }
2289 }
2290
2291 static char *check_for_directory_rename(struct merge_options *o,
2292 const char *path,
2293 struct tree *tree,
2294 struct hashmap *dir_renames,
2295 struct hashmap *dir_rename_exclusions,
2296 struct hashmap *collisions,
2297 int *clean_merge)
2298 {
2299 char *new_path = NULL;
2300 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
2301 struct dir_rename_entry *oentry = NULL;
2302
2303 if (!entry)
2304 return new_path;
2305
2306 /*
2307 * This next part is a little weird. We do not want to do an
2308 * implicit rename into a directory we renamed on our side, because
2309 * that will result in a spurious rename/rename(1to2) conflict. An
2310 * example:
2311 * Base commit: dumbdir/afile, otherdir/bfile
2312 * Side 1: smrtdir/afile, otherdir/bfile
2313 * Side 2: dumbdir/afile, dumbdir/bfile
2314 * Here, while working on Side 1, we could notice that otherdir was
2315 * renamed/merged to dumbdir, and change the diff_filepair for
2316 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
2317 * 2 will notice the rename from dumbdir to smrtdir, and do the
2318 * transitive rename to move it from dumbdir/bfile to
2319 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
2320 * smrtdir, a rename/rename(1to2) conflict. We really just want
2321 * the file to end up in smrtdir. And the way to achieve that is
2322 * to not let Side1 do the rename to dumbdir, since we know that is
2323 * the source of one of our directory renames.
2324 *
2325 * That's why oentry and dir_rename_exclusions is here.
2326 *
2327 * As it turns out, this also prevents N-way transient rename
2328 * confusion; See testcases 9c and 9d of t6043.
2329 */
2330 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
2331 if (oentry) {
2332 output(o, 1, _("WARNING: Avoiding applying %s -> %s rename "
2333 "to %s, because %s itself was renamed."),
2334 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
2335 } else {
2336 new_path = handle_path_level_conflicts(o, path, entry,
2337 collisions, tree);
2338 *clean_merge &= (new_path != NULL);
2339 }
2340
2341 return new_path;
2342 }
2343
2344 static void apply_directory_rename_modifications(struct merge_options *o,
2345 struct diff_filepair *pair,
2346 char *new_path,
2347 struct rename *re,
2348 struct tree *tree,
2349 struct tree *o_tree,
2350 struct tree *a_tree,
2351 struct tree *b_tree,
2352 struct string_list *entries,
2353 int *clean)
2354 {
2355 struct string_list_item *item;
2356 int stage = (tree == a_tree ? 2 : 3);
2357 int update_wd;
2358
2359 /*
2360 * In all cases where we can do directory rename detection,
2361 * unpack_trees() will have read pair->two->path into the
2362 * index and the working copy. We need to remove it so that
2363 * we can instead place it at new_path. It is guaranteed to
2364 * not be untracked (unpack_trees() would have errored out
2365 * saying the file would have been overwritten), but it might
2366 * be dirty, though.
2367 */
2368 update_wd = !was_dirty(o, pair->two->path);
2369 if (!update_wd)
2370 output(o, 1, _("Refusing to lose dirty file at %s"),
2371 pair->two->path);
2372 remove_file(o, 1, pair->two->path, !update_wd);
2373
2374 /* Find or create a new re->dst_entry */
2375 item = string_list_lookup(entries, new_path);
2376 if (item) {
2377 /*
2378 * Since we're renaming on this side of history, and it's
2379 * due to a directory rename on the other side of history
2380 * (which we only allow when the directory in question no
2381 * longer exists on the other side of history), the
2382 * original entry for re->dst_entry is no longer
2383 * necessary...
2384 */
2385 re->dst_entry->processed = 1;
2386
2387 /*
2388 * ...because we'll be using this new one.
2389 */
2390 re->dst_entry = item->util;
2391 } else {
2392 /*
2393 * re->dst_entry is for the before-dir-rename path, and we
2394 * need it to hold information for the after-dir-rename
2395 * path. Before creating a new entry, we need to mark the
2396 * old one as unnecessary (...unless it is shared by
2397 * src_entry, i.e. this didn't use to be a rename, in which
2398 * case we can just allow the normal processing to happen
2399 * for it).
2400 */
2401 if (pair->status == 'R')
2402 re->dst_entry->processed = 1;
2403
2404 re->dst_entry = insert_stage_data(new_path,
2405 o_tree, a_tree, b_tree,
2406 entries);
2407 item = string_list_insert(entries, new_path);
2408 item->util = re->dst_entry;
2409 }
2410
2411 /*
2412 * Update the stage_data with the information about the path we are
2413 * moving into place. That slot will be empty and available for us
2414 * to write to because of the collision checks in
2415 * handle_path_level_conflicts(). In other words,
2416 * re->dst_entry->stages[stage].oid will be the null_oid, so it's
2417 * open for us to write to.
2418 *
2419 * It may be tempting to actually update the index at this point as
2420 * well, using update_stages_for_stage_data(), but as per the big
2421 * "NOTE" in update_stages(), doing so will modify the current
2422 * in-memory index which will break calls to would_lose_untracked()
2423 * that we need to make. Instead, we need to just make sure that
2424 * the various handle_rename_*() functions update the index
2425 * explicitly rather than relying on unpack_trees() to have done it.
2426 */
2427 get_tree_entry(&tree->object.oid,
2428 pair->two->path,
2429 &re->dst_entry->stages[stage].oid,
2430 &re->dst_entry->stages[stage].mode);
2431
2432 /* Update pair status */
2433 if (pair->status == 'A') {
2434 /*
2435 * Recording rename information for this add makes it look
2436 * like a rename/delete conflict. Make sure we can
2437 * correctly handle this as an add that was moved to a new
2438 * directory instead of reporting a rename/delete conflict.
2439 */
2440 re->add_turned_into_rename = 1;
2441 }
2442 /*
2443 * We don't actually look at pair->status again, but it seems
2444 * pedagogically correct to adjust it.
2445 */
2446 pair->status = 'R';
2447
2448 /*
2449 * Finally, record the new location.
2450 */
2451 pair->two->path = new_path;
2452 }
2453
2454 /*
2455 * Get information of all renames which occurred in 'pairs', making use of
2456 * any implicit directory renames inferred from the other side of history.
2457 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
2458 * to be able to associate the correct cache entries with the rename
2459 * information; tree is always equal to either a_tree or b_tree.
2460 */
2461 static struct string_list *get_renames(struct merge_options *o,
2462 struct diff_queue_struct *pairs,
2463 struct hashmap *dir_renames,
2464 struct hashmap *dir_rename_exclusions,
2465 struct tree *tree,
2466 struct tree *o_tree,
2467 struct tree *a_tree,
2468 struct tree *b_tree,
2469 struct string_list *entries,
2470 int *clean_merge)
2471 {
2472 int i;
2473 struct hashmap collisions;
2474 struct hashmap_iter iter;
2475 struct collision_entry *e;
2476 struct string_list *renames;
2477
2478 compute_collisions(&collisions, dir_renames, pairs);
2479 renames = xcalloc(1, sizeof(struct string_list));
2480
2481 for (i = 0; i < pairs->nr; ++i) {
2482 struct string_list_item *item;
2483 struct rename *re;
2484 struct diff_filepair *pair = pairs->queue[i];
2485 char *new_path; /* non-NULL only with directory renames */
2486
2487 if (pair->status != 'A' && pair->status != 'R') {
2488 diff_free_filepair(pair);
2489 continue;
2490 }
2491 new_path = check_for_directory_rename(o, pair->two->path, tree,
2492 dir_renames,
2493 dir_rename_exclusions,
2494 &collisions,
2495 clean_merge);
2496 if (pair->status != 'R' && !new_path) {
2497 diff_free_filepair(pair);
2498 continue;
2499 }
2500
2501 re = xmalloc(sizeof(*re));
2502 re->processed = 0;
2503 re->add_turned_into_rename = 0;
2504 re->pair = pair;
2505 item = string_list_lookup(entries, re->pair->one->path);
2506 if (!item)
2507 re->src_entry = insert_stage_data(re->pair->one->path,
2508 o_tree, a_tree, b_tree, entries);
2509 else
2510 re->src_entry = item->util;
2511
2512 item = string_list_lookup(entries, re->pair->two->path);
2513 if (!item)
2514 re->dst_entry = insert_stage_data(re->pair->two->path,
2515 o_tree, a_tree, b_tree, entries);
2516 else
2517 re->dst_entry = item->util;
2518 item = string_list_insert(renames, pair->one->path);
2519 item->util = re;
2520 if (new_path)
2521 apply_directory_rename_modifications(o, pair, new_path,
2522 re, tree, o_tree,
2523 a_tree, b_tree,
2524 entries,
2525 clean_merge);
2526 }
2527
2528 hashmap_iter_init(&collisions, &iter);
2529 while ((e = hashmap_iter_next(&iter))) {
2530 free(e->target_file);
2531 string_list_clear(&e->source_files, 0);
2532 }
2533 hashmap_free(&collisions, 1);
2534 return renames;
2535 }
2536
2537 static int process_renames(struct merge_options *o,
2538 struct string_list *a_renames,
2539 struct string_list *b_renames)
2540 {
2541 int clean_merge = 1, i, j;
2542 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2543 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2544 const struct rename *sre;
2545
2546 for (i = 0; i < a_renames->nr; i++) {
2547 sre = a_renames->items[i].util;
2548 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2549 = (void *)sre;
2550 }
2551 for (i = 0; i < b_renames->nr; i++) {
2552 sre = b_renames->items[i].util;
2553 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2554 = (void *)sre;
2555 }
2556
2557 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2558 struct string_list *renames1, *renames2Dst;
2559 struct rename *ren1 = NULL, *ren2 = NULL;
2560 const char *branch1, *branch2;
2561 const char *ren1_src, *ren1_dst;
2562 struct string_list_item *lookup;
2563
2564 if (i >= a_renames->nr) {
2565 ren2 = b_renames->items[j++].util;
2566 } else if (j >= b_renames->nr) {
2567 ren1 = a_renames->items[i++].util;
2568 } else {
2569 int compare = strcmp(a_renames->items[i].string,
2570 b_renames->items[j].string);
2571 if (compare <= 0)
2572 ren1 = a_renames->items[i++].util;
2573 if (compare >= 0)
2574 ren2 = b_renames->items[j++].util;
2575 }
2576
2577 /* TODO: refactor, so that 1/2 are not needed */
2578 if (ren1) {
2579 renames1 = a_renames;
2580 renames2Dst = &b_by_dst;
2581 branch1 = o->branch1;
2582 branch2 = o->branch2;
2583 } else {
2584 renames1 = b_renames;
2585 renames2Dst = &a_by_dst;
2586 branch1 = o->branch2;
2587 branch2 = o->branch1;
2588 SWAP(ren2, ren1);
2589 }
2590
2591 if (ren1->processed)
2592 continue;
2593 ren1->processed = 1;
2594 ren1->dst_entry->processed = 1;
2595 /* BUG: We should only mark src_entry as processed if we
2596 * are not dealing with a rename + add-source case.
2597 */
2598 ren1->src_entry->processed = 1;
2599
2600 ren1_src = ren1->pair->one->path;
2601 ren1_dst = ren1->pair->two->path;
2602
2603 if (ren2) {
2604 /* One file renamed on both sides */
2605 const char *ren2_src = ren2->pair->one->path;
2606 const char *ren2_dst = ren2->pair->two->path;
2607 enum rename_type rename_type;
2608 if (strcmp(ren1_src, ren2_src) != 0)
2609 BUG("ren1_src != ren2_src");
2610 ren2->dst_entry->processed = 1;
2611 ren2->processed = 1;
2612 if (strcmp(ren1_dst, ren2_dst) != 0) {
2613 rename_type = RENAME_ONE_FILE_TO_TWO;
2614 clean_merge = 0;
2615 } else {
2616 rename_type = RENAME_ONE_FILE_TO_ONE;
2617 /* BUG: We should only remove ren1_src in
2618 * the base stage (think of rename +
2619 * add-source cases).
2620 */
2621 remove_file(o, 1, ren1_src, 1);
2622 update_entry(ren1->dst_entry,
2623 ren1->pair->one,
2624 ren1->pair->two,
2625 ren2->pair->two);
2626 }
2627 setup_rename_conflict_info(rename_type,
2628 ren1->pair,
2629 ren2->pair,
2630 branch1,
2631 branch2,
2632 ren1->dst_entry,
2633 ren2->dst_entry,
2634 o,
2635 NULL,
2636 NULL);
2637 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2638 /* Two different files renamed to the same thing */
2639 char *ren2_dst;
2640 ren2 = lookup->util;
2641 ren2_dst = ren2->pair->two->path;
2642 if (strcmp(ren1_dst, ren2_dst) != 0)
2643 BUG("ren1_dst != ren2_dst");
2644
2645 clean_merge = 0;
2646 ren2->processed = 1;
2647 /*
2648 * BUG: We should only mark src_entry as processed
2649 * if we are not dealing with a rename + add-source
2650 * case.
2651 */
2652 ren2->src_entry->processed = 1;
2653
2654 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2655 ren1->pair,
2656 ren2->pair,
2657 branch1,
2658 branch2,
2659 ren1->dst_entry,
2660 ren2->dst_entry,
2661 o,
2662 ren1->src_entry,
2663 ren2->src_entry);
2664
2665 } else {
2666 /* Renamed in 1, maybe changed in 2 */
2667 /* we only use sha1 and mode of these */
2668 struct diff_filespec src_other, dst_other;
2669 int try_merge;
2670
2671 /*
2672 * unpack_trees loads entries from common-commit
2673 * into stage 1, from head-commit into stage 2, and
2674 * from merge-commit into stage 3. We keep track
2675 * of which side corresponds to the rename.
2676 */
2677 int renamed_stage = a_renames == renames1 ? 2 : 3;
2678 int other_stage = a_renames == renames1 ? 3 : 2;
2679
2680 /* BUG: We should only remove ren1_src in the base
2681 * stage and in other_stage (think of rename +
2682 * add-source case).
2683 */
2684 remove_file(o, 1, ren1_src,
2685 renamed_stage == 2 || !was_tracked(o, ren1_src));
2686
2687 oidcpy(&src_other.oid,
2688 &ren1->src_entry->stages[other_stage].oid);
2689 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2690 oidcpy(&dst_other.oid,
2691 &ren1->dst_entry->stages[other_stage].oid);
2692 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2693 try_merge = 0;
2694
2695 if (oid_eq(&src_other.oid, &null_oid) &&
2696 ren1->add_turned_into_rename) {
2697 setup_rename_conflict_info(RENAME_VIA_DIR,
2698 ren1->pair,
2699 NULL,
2700 branch1,
2701 branch2,
2702 ren1->dst_entry,
2703 NULL,
2704 o,
2705 NULL,
2706 NULL);
2707 } else if (oid_eq(&src_other.oid, &null_oid)) {
2708 setup_rename_conflict_info(RENAME_DELETE,
2709 ren1->pair,
2710 NULL,
2711 branch1,
2712 branch2,
2713 ren1->dst_entry,
2714 NULL,
2715 o,
2716 NULL,
2717 NULL);
2718 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2719 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2720 /*
2721 * Added file on the other side identical to
2722 * the file being renamed: clean merge.
2723 * Also, there is no need to overwrite the
2724 * file already in the working copy, so call
2725 * update_file_flags() instead of
2726 * update_file().
2727 */
2728 if (update_file_flags(o,
2729 &ren1->pair->two->oid,
2730 ren1->pair->two->mode,
2731 ren1_dst,
2732 1, /* update_cache */
2733 0 /* update_wd */))
2734 clean_merge = -1;
2735 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2736 clean_merge = 0;
2737 try_merge = 1;
2738 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
2739 "%s added in %s"),
2740 ren1_src, ren1_dst, branch1,
2741 ren1_dst, branch2);
2742 if (o->call_depth) {
2743 struct merge_file_info mfi;
2744 struct diff_filespec one, a, b;
2745
2746 oidcpy(&one.oid, &null_oid);
2747 one.mode = 0;
2748 one.path = ren1->pair->two->path;
2749
2750 oidcpy(&a.oid, &ren1->pair->two->oid);
2751 a.mode = ren1->pair->two->mode;
2752 a.path = one.path;
2753
2754 oidcpy(&b.oid, &dst_other.oid);
2755 b.mode = dst_other.mode;
2756 b.path = one.path;
2757
2758 if (merge_mode_and_contents(o, &one, &a, &b, ren1_dst,
2759 branch1, branch2,
2760 &mfi)) {
2761 clean_merge = -1;
2762 goto cleanup_and_return;
2763 }
2764 output(o, 1, _("Adding merged %s"), ren1_dst);
2765 if (update_file(o, 0, &mfi.oid,
2766 mfi.mode, ren1_dst))
2767 clean_merge = -1;
2768 try_merge = 0;
2769 } else {
2770 char *new_path = unique_path(o, ren1_dst, branch2);
2771 output(o, 1, _("Adding as %s instead"), new_path);
2772 if (update_file(o, 0, &dst_other.oid,
2773 dst_other.mode, new_path))
2774 clean_merge = -1;
2775 free(new_path);
2776 }
2777 } else
2778 try_merge = 1;
2779
2780 if (clean_merge < 0)
2781 goto cleanup_and_return;
2782 if (try_merge) {
2783 struct diff_filespec *one, *a, *b;
2784 src_other.path = (char *)ren1_src;
2785
2786 one = ren1->pair->one;
2787 if (a_renames == renames1) {
2788 a = ren1->pair->two;
2789 b = &src_other;
2790 } else {
2791 b = ren1->pair->two;
2792 a = &src_other;
2793 }
2794 update_entry(ren1->dst_entry, one, a, b);
2795 setup_rename_conflict_info(RENAME_NORMAL,
2796 ren1->pair,
2797 NULL,
2798 branch1,
2799 NULL,
2800 ren1->dst_entry,
2801 NULL,
2802 o,
2803 NULL,
2804 NULL);
2805 }
2806 }
2807 }
2808 cleanup_and_return:
2809 string_list_clear(&a_by_dst, 0);
2810 string_list_clear(&b_by_dst, 0);
2811
2812 return clean_merge;
2813 }
2814
2815 struct rename_info {
2816 struct string_list *head_renames;
2817 struct string_list *merge_renames;
2818 };
2819
2820 static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2821 struct hashmap *dir_renames)
2822 {
2823 struct hashmap_iter iter;
2824 struct dir_rename_entry *e;
2825
2826 hashmap_iter_init(dir_renames, &iter);
2827 while ((e = hashmap_iter_next(&iter))) {
2828 free(e->dir);
2829 strbuf_release(&e->new_dir);
2830 /* possible_new_dirs already cleared in get_directory_renames */
2831 }
2832 hashmap_free(dir_renames, 1);
2833 free(dir_renames);
2834
2835 free(pairs->queue);
2836 free(pairs);
2837 }
2838
2839 static int detect_and_process_renames(struct merge_options *o,
2840 struct tree *common,
2841 struct tree *head,
2842 struct tree *merge,
2843 struct string_list *entries,
2844 struct rename_info *ri)
2845 {
2846 struct diff_queue_struct *head_pairs, *merge_pairs;
2847 struct hashmap *dir_re_head, *dir_re_merge;
2848 int clean = 1;
2849
2850 ri->head_renames = NULL;
2851 ri->merge_renames = NULL;
2852
2853 if (!merge_detect_rename(o))
2854 return 1;
2855
2856 head_pairs = get_diffpairs(o, common, head);
2857 merge_pairs = get_diffpairs(o, common, merge);
2858
2859 if (o->detect_directory_renames) {
2860 dir_re_head = get_directory_renames(head_pairs, head);
2861 dir_re_merge = get_directory_renames(merge_pairs, merge);
2862
2863 handle_directory_level_conflicts(o,
2864 dir_re_head, head,
2865 dir_re_merge, merge);
2866 } else {
2867 dir_re_head = xmalloc(sizeof(*dir_re_head));
2868 dir_re_merge = xmalloc(sizeof(*dir_re_merge));
2869 dir_rename_init(dir_re_head);
2870 dir_rename_init(dir_re_merge);
2871 }
2872
2873 ri->head_renames = get_renames(o, head_pairs,
2874 dir_re_merge, dir_re_head, head,
2875 common, head, merge, entries,
2876 &clean);
2877 if (clean < 0)
2878 goto cleanup;
2879 ri->merge_renames = get_renames(o, merge_pairs,
2880 dir_re_head, dir_re_merge, merge,
2881 common, head, merge, entries,
2882 &clean);
2883 if (clean < 0)
2884 goto cleanup;
2885 clean &= process_renames(o, ri->head_renames, ri->merge_renames);
2886
2887 cleanup:
2888 /*
2889 * Some cleanup is deferred until cleanup_renames() because the
2890 * data structures are still needed and referenced in
2891 * process_entry(). But there are a few things we can free now.
2892 */
2893 initial_cleanup_rename(head_pairs, dir_re_head);
2894 initial_cleanup_rename(merge_pairs, dir_re_merge);
2895
2896 return clean;
2897 }
2898
2899 static void final_cleanup_rename(struct string_list *rename)
2900 {
2901 const struct rename *re;
2902 int i;
2903
2904 if (rename == NULL)
2905 return;
2906
2907 for (i = 0; i < rename->nr; i++) {
2908 re = rename->items[i].util;
2909 diff_free_filepair(re->pair);
2910 }
2911 string_list_clear(rename, 1);
2912 free(rename);
2913 }
2914
2915 static void final_cleanup_renames(struct rename_info *re_info)
2916 {
2917 final_cleanup_rename(re_info->head_renames);
2918 final_cleanup_rename(re_info->merge_renames);
2919 }
2920
2921 static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
2922 {
2923 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
2924 }
2925
2926 static int read_oid_strbuf(struct merge_options *o,
2927 const struct object_id *oid,
2928 struct strbuf *dst)
2929 {
2930 void *buf;
2931 enum object_type type;
2932 unsigned long size;
2933 buf = read_object_file(oid, &type, &size);
2934 if (!buf)
2935 return err(o, _("cannot read object %s"), oid_to_hex(oid));
2936 if (type != OBJ_BLOB) {
2937 free(buf);
2938 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
2939 }
2940 strbuf_attach(dst, buf, size, size + 1);
2941 return 0;
2942 }
2943
2944 static int blob_unchanged(struct merge_options *opt,
2945 const struct object_id *o_oid,
2946 unsigned o_mode,
2947 const struct object_id *a_oid,
2948 unsigned a_mode,
2949 int renormalize, const char *path)
2950 {
2951 struct strbuf o = STRBUF_INIT;
2952 struct strbuf a = STRBUF_INIT;
2953 int ret = 0; /* assume changed for safety */
2954
2955 if (a_mode != o_mode)
2956 return 0;
2957 if (oid_eq(o_oid, a_oid))
2958 return 1;
2959 if (!renormalize)
2960 return 0;
2961
2962 assert(o_oid && a_oid);
2963 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
2964 goto error_return;
2965 /*
2966 * Note: binary | is used so that both renormalizations are
2967 * performed. Comparison can be skipped if both files are
2968 * unchanged since their sha1s have already been compared.
2969 */
2970 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
2971 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
2972 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
2973
2974 error_return:
2975 strbuf_release(&o);
2976 strbuf_release(&a);
2977 return ret;
2978 }
2979
2980 static int handle_modify_delete(struct merge_options *o,
2981 const char *path,
2982 struct object_id *o_oid, int o_mode,
2983 struct object_id *a_oid, int a_mode,
2984 struct object_id *b_oid, int b_mode)
2985 {
2986 const char *modify_branch, *delete_branch;
2987 struct object_id *changed_oid;
2988 int changed_mode;
2989
2990 if (a_oid) {
2991 modify_branch = o->branch1;
2992 delete_branch = o->branch2;
2993 changed_oid = a_oid;
2994 changed_mode = a_mode;
2995 } else {
2996 modify_branch = o->branch2;
2997 delete_branch = o->branch1;
2998 changed_oid = b_oid;
2999 changed_mode = b_mode;
3000 }
3001
3002 return handle_change_delete(o,
3003 path, NULL,
3004 o_oid, o_mode,
3005 changed_oid, changed_mode,
3006 modify_branch, delete_branch,
3007 _("modify"), _("modified"));
3008 }
3009
3010 static int handle_content_merge(struct merge_options *o,
3011 const char *path,
3012 int is_dirty,
3013 struct object_id *o_oid, int o_mode,
3014 struct object_id *a_oid, int a_mode,
3015 struct object_id *b_oid, int b_mode,
3016 struct rename_conflict_info *rename_conflict_info)
3017 {
3018 const char *reason = _("content");
3019 const char *path1 = NULL, *path2 = NULL;
3020 struct merge_file_info mfi;
3021 struct diff_filespec one, a, b;
3022 unsigned df_conflict_remains = 0;
3023
3024 if (!o_oid) {
3025 reason = _("add/add");
3026 o_oid = (struct object_id *)&null_oid;
3027 }
3028 one.path = a.path = b.path = (char *)path;
3029 oidcpy(&one.oid, o_oid);
3030 one.mode = o_mode;
3031 oidcpy(&a.oid, a_oid);
3032 a.mode = a_mode;
3033 oidcpy(&b.oid, b_oid);
3034 b.mode = b_mode;
3035
3036 if (rename_conflict_info) {
3037 struct diff_filepair *pair1 = rename_conflict_info->pair1;
3038
3039 path1 = (o->branch1 == rename_conflict_info->branch1) ?
3040 pair1->two->path : pair1->one->path;
3041 /* If rename_conflict_info->pair2 != NULL, we are in
3042 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
3043 * normal rename.
3044 */
3045 path2 = (rename_conflict_info->pair2 ||
3046 o->branch2 == rename_conflict_info->branch1) ?
3047 pair1->two->path : pair1->one->path;
3048 one.path = pair1->one->path;
3049 a.path = (char *)path1;
3050 b.path = (char *)path2;
3051
3052 if (dir_in_way(path, !o->call_depth,
3053 S_ISGITLINK(pair1->two->mode)))
3054 df_conflict_remains = 1;
3055 }
3056 if (merge_mode_and_contents(o, &one, &a, &b, path,
3057 o->branch1, o->branch2, &mfi))
3058 return -1;
3059
3060 /*
3061 * We can skip updating the working tree file iff:
3062 * a) The merge is clean
3063 * b) The merge matches what was in HEAD (content, mode, pathname)
3064 * c) The target path is usable (i.e. not involved in D/F conflict)
3065 */
3066 if (mfi.clean &&
3067 was_tracked_and_matches(o, path, &mfi.oid, mfi.mode) &&
3068 !df_conflict_remains) {
3069 int pos;
3070 struct cache_entry *ce;
3071
3072 output(o, 3, _("Skipped %s (merged same as existing)"), path);
3073 if (add_cacheinfo(o, mfi.mode, &mfi.oid, path,
3074 0, (!o->call_depth && !is_dirty), 0))
3075 return -1;
3076 /*
3077 * However, add_cacheinfo() will delete the old cache entry
3078 * and add a new one. We need to copy over any skip_worktree
3079 * flag to avoid making the file appear as if it were
3080 * deleted by the user.
3081 */
3082 pos = index_name_pos(&o->orig_index, path, strlen(path));
3083 ce = o->orig_index.cache[pos];
3084 if (ce_skip_worktree(ce)) {
3085 pos = index_name_pos(&the_index, path, strlen(path));
3086 ce = the_index.cache[pos];
3087 ce->ce_flags |= CE_SKIP_WORKTREE;
3088 }
3089 return mfi.clean;
3090 }
3091
3092 if (!mfi.clean) {
3093 if (S_ISGITLINK(mfi.mode))
3094 reason = _("submodule");
3095 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
3096 reason, path);
3097 if (rename_conflict_info && !df_conflict_remains)
3098 if (update_stages(o, path, &one, &a, &b))
3099 return -1;
3100 }
3101
3102 if (df_conflict_remains || is_dirty) {
3103 char *new_path;
3104 if (o->call_depth) {
3105 remove_file_from_cache(path);
3106 } else {
3107 if (!mfi.clean) {
3108 if (update_stages(o, path, &one, &a, &b))
3109 return -1;
3110 } else {
3111 int file_from_stage2 = was_tracked(o, path);
3112 struct diff_filespec merged;
3113 oidcpy(&merged.oid, &mfi.oid);
3114 merged.mode = mfi.mode;
3115
3116 if (update_stages(o, path, NULL,
3117 file_from_stage2 ? &merged : NULL,
3118 file_from_stage2 ? NULL : &merged))
3119 return -1;
3120 }
3121
3122 }
3123 new_path = unique_path(o, path, rename_conflict_info->branch1);
3124 if (is_dirty) {
3125 output(o, 1, _("Refusing to lose dirty file at %s"),
3126 path);
3127 }
3128 output(o, 1, _("Adding as %s instead"), new_path);
3129 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
3130 free(new_path);
3131 return -1;
3132 }
3133 free(new_path);
3134 mfi.clean = 0;
3135 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
3136 return -1;
3137 return !is_dirty && mfi.clean;
3138 }
3139
3140 static int handle_rename_normal(struct merge_options *o,
3141 const char *path,
3142 struct object_id *o_oid, unsigned int o_mode,
3143 struct object_id *a_oid, unsigned int a_mode,
3144 struct object_id *b_oid, unsigned int b_mode,
3145 struct rename_conflict_info *ci)
3146 {
3147 /* Merge the content and write it out */
3148 return handle_content_merge(o, path, was_dirty(o, path),
3149 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3150 ci);
3151 }
3152
3153 /* Per entry merge function */
3154 static int process_entry(struct merge_options *o,
3155 const char *path, struct stage_data *entry)
3156 {
3157 int clean_merge = 1;
3158 int normalize = o->renormalize;
3159 unsigned o_mode = entry->stages[1].mode;
3160 unsigned a_mode = entry->stages[2].mode;
3161 unsigned b_mode = entry->stages[3].mode;
3162 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
3163 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
3164 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
3165
3166 entry->processed = 1;
3167 if (entry->rename_conflict_info) {
3168 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
3169 switch (conflict_info->rename_type) {
3170 case RENAME_NORMAL:
3171 case RENAME_ONE_FILE_TO_ONE:
3172 clean_merge = handle_rename_normal(o,
3173 path,
3174 o_oid, o_mode,
3175 a_oid, a_mode,
3176 b_oid, b_mode,
3177 conflict_info);
3178 break;
3179 case RENAME_VIA_DIR:
3180 clean_merge = 1;
3181 if (handle_rename_via_dir(o,
3182 conflict_info->pair1,
3183 conflict_info->branch1,
3184 conflict_info->branch2))
3185 clean_merge = -1;
3186 break;
3187 case RENAME_DELETE:
3188 clean_merge = 0;
3189 if (handle_rename_delete(o,
3190 conflict_info->pair1,
3191 conflict_info->branch1,
3192 conflict_info->branch2))
3193 clean_merge = -1;
3194 break;
3195 case RENAME_ONE_FILE_TO_TWO:
3196 clean_merge = 0;
3197 if (handle_rename_rename_1to2(o, conflict_info))
3198 clean_merge = -1;
3199 break;
3200 case RENAME_TWO_FILES_TO_ONE:
3201 clean_merge = 0;
3202 if (handle_rename_rename_2to1(o, conflict_info))
3203 clean_merge = -1;
3204 break;
3205 default:
3206 entry->processed = 0;
3207 break;
3208 }
3209 } else if (o_oid && (!a_oid || !b_oid)) {
3210 /* Case A: Deleted in one */
3211 if ((!a_oid && !b_oid) ||
3212 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
3213 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
3214 /* Deleted in both or deleted in one and
3215 * unchanged in the other */
3216 if (a_oid)
3217 output(o, 2, _("Removing %s"), path);
3218 /* do not touch working file if it did not exist */
3219 remove_file(o, 1, path, !a_oid);
3220 } else {
3221 /* Modify/delete; deleted side may have put a directory in the way */
3222 clean_merge = 0;
3223 if (handle_modify_delete(o, path, o_oid, o_mode,
3224 a_oid, a_mode, b_oid, b_mode))
3225 clean_merge = -1;
3226 }
3227 } else if ((!o_oid && a_oid && !b_oid) ||
3228 (!o_oid && !a_oid && b_oid)) {
3229 /* Case B: Added in one. */
3230 /* [nothing|directory] -> ([nothing|directory], file) */
3231
3232 const char *add_branch;
3233 const char *other_branch;
3234 unsigned mode;
3235 const struct object_id *oid;
3236 const char *conf;
3237
3238 if (a_oid) {
3239 add_branch = o->branch1;
3240 other_branch = o->branch2;
3241 mode = a_mode;
3242 oid = a_oid;
3243 conf = _("file/directory");
3244 } else {
3245 add_branch = o->branch2;
3246 other_branch = o->branch1;
3247 mode = b_mode;
3248 oid = b_oid;
3249 conf = _("directory/file");
3250 }
3251 if (dir_in_way(path,
3252 !o->call_depth && !S_ISGITLINK(a_mode),
3253 0)) {
3254 char *new_path = unique_path(o, path, add_branch);
3255 clean_merge = 0;
3256 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
3257 "Adding %s as %s"),
3258 conf, path, other_branch, path, new_path);
3259 if (update_file(o, 0, oid, mode, new_path))
3260 clean_merge = -1;
3261 else if (o->call_depth)
3262 remove_file_from_cache(path);
3263 free(new_path);
3264 } else {
3265 output(o, 2, _("Adding %s"), path);
3266 /* do not overwrite file if already present */
3267 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
3268 clean_merge = -1;
3269 }
3270 } else if (a_oid && b_oid) {
3271 /* Case C: Added in both (check for same permissions) and */
3272 /* case D: Modified in both, but differently. */
3273 int is_dirty = 0; /* unpack_trees would have bailed if dirty */
3274 clean_merge = handle_content_merge(o, path, is_dirty,
3275 o_oid, o_mode,
3276 a_oid, a_mode,
3277 b_oid, b_mode,
3278 NULL);
3279 } else if (!o_oid && !a_oid && !b_oid) {
3280 /*
3281 * this entry was deleted altogether. a_mode == 0 means
3282 * we had that path and want to actively remove it.
3283 */
3284 remove_file(o, 1, path, !a_mode);
3285 } else
3286 BUG("fatal merge failure, shouldn't happen.");
3287
3288 return clean_merge;
3289 }
3290
3291 int merge_trees(struct merge_options *o,
3292 struct tree *head,
3293 struct tree *merge,
3294 struct tree *common,
3295 struct tree **result)
3296 {
3297 int code, clean;
3298 struct strbuf sb = STRBUF_INIT;
3299
3300 if (!o->call_depth && index_has_changes(&the_index, head, &sb)) {
3301 err(o, _("Your local changes to the following files would be overwritten by merge:\n %s"),
3302 sb.buf);
3303 return -1;
3304 }
3305
3306 if (o->subtree_shift) {
3307 merge = shift_tree_object(head, merge, o->subtree_shift);
3308 common = shift_tree_object(head, common, o->subtree_shift);
3309 }
3310
3311 if (oid_eq(&common->object.oid, &merge->object.oid)) {
3312 output(o, 0, _("Already up to date!"));
3313 *result = head;
3314 return 1;
3315 }
3316
3317 code = unpack_trees_start(o, common, head, merge);
3318
3319 if (code != 0) {
3320 if (show(o, 4) || o->call_depth)
3321 err(o, _("merging of trees %s and %s failed"),
3322 oid_to_hex(&head->object.oid),
3323 oid_to_hex(&merge->object.oid));
3324 unpack_trees_finish(o);
3325 return -1;
3326 }
3327
3328 if (unmerged_cache()) {
3329 struct string_list *entries;
3330 struct rename_info re_info;
3331 int i;
3332 /*
3333 * Only need the hashmap while processing entries, so
3334 * initialize it here and free it when we are done running
3335 * through the entries. Keeping it in the merge_options as
3336 * opposed to decaring a local hashmap is for convenience
3337 * so that we don't have to pass it to around.
3338 */
3339 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
3340 get_files_dirs(o, head);
3341 get_files_dirs(o, merge);
3342
3343 entries = get_unmerged();
3344 clean = detect_and_process_renames(o, common, head, merge,
3345 entries, &re_info);
3346 record_df_conflict_files(o, entries);
3347 if (clean < 0)
3348 goto cleanup;
3349 for (i = entries->nr-1; 0 <= i; i--) {
3350 const char *path = entries->items[i].string;
3351 struct stage_data *e = entries->items[i].util;
3352 if (!e->processed) {
3353 int ret = process_entry(o, path, e);
3354 if (!ret)
3355 clean = 0;
3356 else if (ret < 0) {
3357 clean = ret;
3358 goto cleanup;
3359 }
3360 }
3361 }
3362 for (i = 0; i < entries->nr; i++) {
3363 struct stage_data *e = entries->items[i].util;
3364 if (!e->processed)
3365 BUG("unprocessed path??? %s",
3366 entries->items[i].string);
3367 }
3368
3369 cleanup:
3370 final_cleanup_renames(&re_info);
3371
3372 string_list_clear(entries, 1);
3373 free(entries);
3374
3375 hashmap_free(&o->current_file_dir_set, 1);
3376
3377 if (clean < 0) {
3378 unpack_trees_finish(o);
3379 return clean;
3380 }
3381 }
3382 else
3383 clean = 1;
3384
3385 unpack_trees_finish(o);
3386
3387 if (o->call_depth && !(*result = write_tree_from_memory(o)))
3388 return -1;
3389
3390 return clean;
3391 }
3392
3393 static struct commit_list *reverse_commit_list(struct commit_list *list)
3394 {
3395 struct commit_list *next = NULL, *current, *backup;
3396 for (current = list; current; current = backup) {
3397 backup = current->next;
3398 current->next = next;
3399 next = current;
3400 }
3401 return next;
3402 }
3403
3404 /*
3405 * Merge the commits h1 and h2, return the resulting virtual
3406 * commit object and a flag indicating the cleanness of the merge.
3407 */
3408 int merge_recursive(struct merge_options *o,
3409 struct commit *h1,
3410 struct commit *h2,
3411 struct commit_list *ca,
3412 struct commit **result)
3413 {
3414 struct commit_list *iter;
3415 struct commit *merged_common_ancestors;
3416 struct tree *mrtree;
3417 int clean;
3418
3419 if (show(o, 4)) {
3420 output(o, 4, _("Merging:"));
3421 output_commit_title(o, h1);
3422 output_commit_title(o, h2);
3423 }
3424
3425 if (!ca) {
3426 ca = get_merge_bases(h1, h2);
3427 ca = reverse_commit_list(ca);
3428 }
3429
3430 if (show(o, 5)) {
3431 unsigned cnt = commit_list_count(ca);
3432
3433 output(o, 5, Q_("found %u common ancestor:",
3434 "found %u common ancestors:", cnt), cnt);
3435 for (iter = ca; iter; iter = iter->next)
3436 output_commit_title(o, iter->item);
3437 }
3438
3439 merged_common_ancestors = pop_commit(&ca);
3440 if (merged_common_ancestors == NULL) {
3441 /* if there is no common ancestor, use an empty tree */
3442 struct tree *tree;
3443
3444 tree = lookup_tree(the_repository, the_repository->hash_algo->empty_tree);
3445 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
3446 }
3447
3448 for (iter = ca; iter; iter = iter->next) {
3449 const char *saved_b1, *saved_b2;
3450 o->call_depth++;
3451 /*
3452 * When the merge fails, the result contains files
3453 * with conflict markers. The cleanness flag is
3454 * ignored (unless indicating an error), it was never
3455 * actually used, as result of merge_trees has always
3456 * overwritten it: the committed "conflicts" were
3457 * already resolved.
3458 */
3459 discard_cache();
3460 saved_b1 = o->branch1;
3461 saved_b2 = o->branch2;
3462 o->branch1 = "Temporary merge branch 1";
3463 o->branch2 = "Temporary merge branch 2";
3464 if (merge_recursive(o, merged_common_ancestors, iter->item,
3465 NULL, &merged_common_ancestors) < 0)
3466 return -1;
3467 o->branch1 = saved_b1;
3468 o->branch2 = saved_b2;
3469 o->call_depth--;
3470
3471 if (!merged_common_ancestors)
3472 return err(o, _("merge returned no commit"));
3473 }
3474
3475 discard_cache();
3476 if (!o->call_depth)
3477 read_cache();
3478
3479 o->ancestor = "merged common ancestors";
3480 clean = merge_trees(o, get_commit_tree(h1), get_commit_tree(h2),
3481 get_commit_tree(merged_common_ancestors),
3482 &mrtree);
3483 if (clean < 0) {
3484 flush_output(o);
3485 return clean;
3486 }
3487
3488 if (o->call_depth) {
3489 *result = make_virtual_commit(mrtree, "merged tree");
3490 commit_list_insert(h1, &(*result)->parents);
3491 commit_list_insert(h2, &(*result)->parents->next);
3492 }
3493 flush_output(o);
3494 if (!o->call_depth && o->buffer_output < 2)
3495 strbuf_release(&o->obuf);
3496 if (show(o, 2))
3497 diff_warn_rename_limit("merge.renamelimit",
3498 o->needed_rename_limit, 0);
3499 return clean;
3500 }
3501
3502 static struct commit *get_ref(const struct object_id *oid, const char *name)
3503 {
3504 struct object *object;
3505
3506 object = deref_tag(the_repository, parse_object(the_repository, oid),
3507 name,
3508 strlen(name));
3509 if (!object)
3510 return NULL;
3511 if (object->type == OBJ_TREE)
3512 return make_virtual_commit((struct tree*)object, name);
3513 if (object->type != OBJ_COMMIT)
3514 return NULL;
3515 if (parse_commit((struct commit *)object))
3516 return NULL;
3517 return (struct commit *)object;
3518 }
3519
3520 int merge_recursive_generic(struct merge_options *o,
3521 const struct object_id *head,
3522 const struct object_id *merge,
3523 int num_base_list,
3524 const struct object_id **base_list,
3525 struct commit **result)
3526 {
3527 int clean;
3528 struct lock_file lock = LOCK_INIT;
3529 struct commit *head_commit = get_ref(head, o->branch1);
3530 struct commit *next_commit = get_ref(merge, o->branch2);
3531 struct commit_list *ca = NULL;
3532
3533 if (base_list) {
3534 int i;
3535 for (i = 0; i < num_base_list; ++i) {
3536 struct commit *base;
3537 if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i]))))
3538 return err(o, _("Could not parse object '%s'"),
3539 oid_to_hex(base_list[i]));
3540 commit_list_insert(base, &ca);
3541 }
3542 }
3543
3544 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
3545 clean = merge_recursive(o, head_commit, next_commit, ca,
3546 result);
3547 if (clean < 0) {
3548 rollback_lock_file(&lock);
3549 return clean;
3550 }
3551
3552 if (write_locked_index(&the_index, &lock,
3553 COMMIT_LOCK | SKIP_IF_UNCHANGED))
3554 return err(o, _("Unable to write index."));
3555
3556 return clean ? 0 : 1;
3557 }
3558
3559 static void merge_recursive_config(struct merge_options *o)
3560 {
3561 char *value = NULL;
3562 git_config_get_int("merge.verbosity", &o->verbosity);
3563 git_config_get_int("diff.renamelimit", &o->diff_rename_limit);
3564 git_config_get_int("merge.renamelimit", &o->merge_rename_limit);
3565 if (!git_config_get_string("diff.renames", &value)) {
3566 o->diff_detect_rename = git_config_rename("diff.renames", value);
3567 free(value);
3568 }
3569 if (!git_config_get_string("merge.renames", &value)) {
3570 o->merge_detect_rename = git_config_rename("merge.renames", value);
3571 free(value);
3572 }
3573 git_config(git_xmerge_config, NULL);
3574 }
3575
3576 void init_merge_options(struct merge_options *o)
3577 {
3578 const char *merge_verbosity;
3579 memset(o, 0, sizeof(struct merge_options));
3580 o->verbosity = 2;
3581 o->buffer_output = 1;
3582 o->diff_rename_limit = -1;
3583 o->merge_rename_limit = -1;
3584 o->renormalize = 0;
3585 o->diff_detect_rename = -1;
3586 o->merge_detect_rename = -1;
3587 o->detect_directory_renames = 1;
3588 merge_recursive_config(o);
3589 merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
3590 if (merge_verbosity)
3591 o->verbosity = strtol(merge_verbosity, NULL, 10);
3592 if (o->verbosity >= 5)
3593 o->buffer_output = 0;
3594 strbuf_init(&o->obuf, 0);
3595 string_list_init(&o->df_conflict_file_set, 1);
3596 }
3597
3598 int parse_merge_opt(struct merge_options *o, const char *s)
3599 {
3600 const char *arg;
3601
3602 if (!s || !*s)
3603 return -1;
3604 if (!strcmp(s, "ours"))
3605 o->recursive_variant = MERGE_RECURSIVE_OURS;
3606 else if (!strcmp(s, "theirs"))
3607 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
3608 else if (!strcmp(s, "subtree"))
3609 o->subtree_shift = "";
3610 else if (skip_prefix(s, "subtree=", &arg))
3611 o->subtree_shift = arg;
3612 else if (!strcmp(s, "patience"))