read-cache.c: kill read_index()
[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_ADD,
190 RENAME_DELETE,
191 RENAME_ONE_FILE_TO_ONE,
192 RENAME_ONE_FILE_TO_TWO,
193 RENAME_TWO_FILES_TO_ONE
194 };
195
196 struct rename_conflict_info {
197 enum rename_type rename_type;
198 struct diff_filepair *pair1;
199 struct diff_filepair *pair2;
200 const char *branch1;
201 const char *branch2;
202 struct stage_data *dst_entry1;
203 struct stage_data *dst_entry2;
204 struct diff_filespec ren1_other;
205 struct diff_filespec ren2_other;
206 };
207
208 /*
209 * Since we want to write the index eventually, we cannot reuse the index
210 * for these (temporary) data.
211 */
212 struct stage_data {
213 struct {
214 unsigned mode;
215 struct object_id oid;
216 } stages[4];
217 struct rename_conflict_info *rename_conflict_info;
218 unsigned processed:1;
219 };
220
221 static inline void setup_rename_conflict_info(enum rename_type rename_type,
222 struct diff_filepair *pair1,
223 struct diff_filepair *pair2,
224 const char *branch1,
225 const char *branch2,
226 struct stage_data *dst_entry1,
227 struct stage_data *dst_entry2,
228 struct merge_options *o,
229 struct stage_data *src_entry1,
230 struct stage_data *src_entry2)
231 {
232 int ostage1 = 0, ostage2;
233 struct rename_conflict_info *ci;
234
235 /*
236 * When we have two renames involved, it's easiest to get the
237 * correct things into stage 2 and 3, and to make sure that the
238 * content merge puts HEAD before the other branch if we just
239 * ensure that branch1 == o->branch1. So, simply flip arguments
240 * around if we don't have that.
241 */
242 if (dst_entry2 && branch1 != o->branch1) {
243 setup_rename_conflict_info(rename_type,
244 pair2, pair1,
245 branch2, branch1,
246 dst_entry2, dst_entry1,
247 o,
248 src_entry2, src_entry1);
249 return;
250 }
251
252 ci = xcalloc(1, sizeof(struct rename_conflict_info));
253 ci->rename_type = rename_type;
254 ci->pair1 = pair1;
255 ci->branch1 = branch1;
256 ci->branch2 = branch2;
257
258 ci->dst_entry1 = dst_entry1;
259 dst_entry1->rename_conflict_info = ci;
260 dst_entry1->processed = 0;
261
262 assert(!pair2 == !dst_entry2);
263 if (dst_entry2) {
264 ci->dst_entry2 = dst_entry2;
265 ci->pair2 = pair2;
266 dst_entry2->rename_conflict_info = ci;
267 }
268
269 /*
270 * For each rename, there could have been
271 * modifications on the side of history where that
272 * file was not renamed.
273 */
274 if (rename_type == RENAME_ADD ||
275 rename_type == RENAME_TWO_FILES_TO_ONE) {
276 ostage1 = o->branch1 == branch1 ? 3 : 2;
277
278 ci->ren1_other.path = pair1->one->path;
279 oidcpy(&ci->ren1_other.oid, &src_entry1->stages[ostage1].oid);
280 ci->ren1_other.mode = src_entry1->stages[ostage1].mode;
281 }
282
283 if (rename_type == RENAME_TWO_FILES_TO_ONE) {
284 ostage2 = ostage1 ^ 1;
285
286 ci->ren2_other.path = pair2->one->path;
287 oidcpy(&ci->ren2_other.oid, &src_entry2->stages[ostage2].oid);
288 ci->ren2_other.mode = src_entry2->stages[ostage2].mode;
289 }
290 }
291
292 static int show(struct merge_options *o, int v)
293 {
294 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
295 }
296
297 __attribute__((format (printf, 3, 4)))
298 static void output(struct merge_options *o, int v, const char *fmt, ...)
299 {
300 va_list ap;
301
302 if (!show(o, v))
303 return;
304
305 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
306
307 va_start(ap, fmt);
308 strbuf_vaddf(&o->obuf, fmt, ap);
309 va_end(ap);
310
311 strbuf_addch(&o->obuf, '\n');
312 if (!o->buffer_output)
313 flush_output(o);
314 }
315
316 static void output_commit_title(struct merge_options *o, struct commit *commit)
317 {
318 struct merge_remote_desc *desc;
319
320 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
321 desc = merge_remote_util(commit);
322 if (desc)
323 strbuf_addf(&o->obuf, "virtual %s\n", desc->name);
324 else {
325 strbuf_add_unique_abbrev(&o->obuf, &commit->object.oid,
326 DEFAULT_ABBREV);
327 strbuf_addch(&o->obuf, ' ');
328 if (parse_commit(commit) != 0)
329 strbuf_addstr(&o->obuf, _("(bad commit)\n"));
330 else {
331 const char *title;
332 const char *msg = get_commit_buffer(commit, NULL);
333 int len = find_commit_subject(msg, &title);
334 if (len)
335 strbuf_addf(&o->obuf, "%.*s\n", len, title);
336 unuse_commit_buffer(commit, msg);
337 }
338 }
339 flush_output(o);
340 }
341
342 static int add_cacheinfo(struct merge_options *o,
343 unsigned int mode, const struct object_id *oid,
344 const char *path, int stage, int refresh, int options)
345 {
346 struct cache_entry *ce;
347 int ret;
348
349 ce = make_cache_entry(&the_index, mode, oid ? oid : &null_oid, path, stage, 0);
350 if (!ce)
351 return err(o, _("add_cacheinfo failed for path '%s'; merge aborting."), path);
352
353 ret = add_cache_entry(ce, options);
354 if (refresh) {
355 struct cache_entry *nce;
356
357 nce = refresh_cache_entry(&the_index, ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
358 if (!nce)
359 return err(o, _("add_cacheinfo failed to refresh for path '%s'; merge aborting."), path);
360 if (nce != ce)
361 ret = add_cache_entry(nce, options);
362 }
363 return ret;
364 }
365
366 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
367 {
368 parse_tree(tree);
369 init_tree_desc(desc, tree->buffer, tree->size);
370 }
371
372 static int unpack_trees_start(struct merge_options *o,
373 struct tree *common,
374 struct tree *head,
375 struct tree *merge)
376 {
377 int rc;
378 struct tree_desc t[3];
379 struct index_state tmp_index = { NULL };
380
381 memset(&o->unpack_opts, 0, sizeof(o->unpack_opts));
382 if (o->call_depth)
383 o->unpack_opts.index_only = 1;
384 else
385 o->unpack_opts.update = 1;
386 o->unpack_opts.merge = 1;
387 o->unpack_opts.head_idx = 2;
388 o->unpack_opts.fn = threeway_merge;
389 o->unpack_opts.src_index = &the_index;
390 o->unpack_opts.dst_index = &tmp_index;
391 o->unpack_opts.aggressive = !merge_detect_rename(o);
392 setup_unpack_trees_porcelain(&o->unpack_opts, "merge");
393
394 init_tree_desc_from_tree(t+0, common);
395 init_tree_desc_from_tree(t+1, head);
396 init_tree_desc_from_tree(t+2, merge);
397
398 rc = unpack_trees(3, t, &o->unpack_opts);
399 cache_tree_free(&active_cache_tree);
400
401 /*
402 * Update the_index to match the new results, AFTER saving a copy
403 * in o->orig_index. Update src_index to point to the saved copy.
404 * (verify_uptodate() checks src_index, and the original index is
405 * the one that had the necessary modification timestamps.)
406 */
407 o->orig_index = the_index;
408 the_index = tmp_index;
409 o->unpack_opts.src_index = &o->orig_index;
410
411 return rc;
412 }
413
414 static void unpack_trees_finish(struct merge_options *o)
415 {
416 discard_index(&o->orig_index);
417 clear_unpack_trees_porcelain(&o->unpack_opts);
418 }
419
420 struct tree *write_tree_from_memory(struct merge_options *o)
421 {
422 struct tree *result = NULL;
423
424 if (unmerged_cache()) {
425 int i;
426 fprintf(stderr, "BUG: There are unmerged index entries:\n");
427 for (i = 0; i < active_nr; i++) {
428 const struct cache_entry *ce = active_cache[i];
429 if (ce_stage(ce))
430 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
431 (int)ce_namelen(ce), ce->name);
432 }
433 BUG("unmerged index entries in merge-recursive.c");
434 }
435
436 if (!active_cache_tree)
437 active_cache_tree = cache_tree();
438
439 if (!cache_tree_fully_valid(active_cache_tree) &&
440 cache_tree_update(&the_index, 0) < 0) {
441 err(o, _("error building trees"));
442 return NULL;
443 }
444
445 result = lookup_tree(the_repository, &active_cache_tree->oid);
446
447 return result;
448 }
449
450 static int save_files_dirs(const struct object_id *oid,
451 struct strbuf *base, const char *path,
452 unsigned int mode, int stage, void *context)
453 {
454 struct path_hashmap_entry *entry;
455 int baselen = base->len;
456 struct merge_options *o = context;
457
458 strbuf_addstr(base, path);
459
460 FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
461 hashmap_entry_init(entry, path_hash(entry->path));
462 hashmap_add(&o->current_file_dir_set, entry);
463
464 strbuf_setlen(base, baselen);
465 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
466 }
467
468 static void get_files_dirs(struct merge_options *o, struct tree *tree)
469 {
470 struct pathspec match_all;
471 memset(&match_all, 0, sizeof(match_all));
472 read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
473 }
474
475 static int get_tree_entry_if_blob(const struct object_id *tree,
476 const char *path,
477 struct object_id *hashy,
478 unsigned int *mode_o)
479 {
480 int ret;
481
482 ret = get_tree_entry(tree, path, hashy, mode_o);
483 if (S_ISDIR(*mode_o)) {
484 oidcpy(hashy, &null_oid);
485 *mode_o = 0;
486 }
487 return ret;
488 }
489
490 /*
491 * Returns an index_entry instance which doesn't have to correspond to
492 * a real cache entry in Git's index.
493 */
494 static struct stage_data *insert_stage_data(const char *path,
495 struct tree *o, struct tree *a, struct tree *b,
496 struct string_list *entries)
497 {
498 struct string_list_item *item;
499 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
500 get_tree_entry_if_blob(&o->object.oid, path,
501 &e->stages[1].oid, &e->stages[1].mode);
502 get_tree_entry_if_blob(&a->object.oid, path,
503 &e->stages[2].oid, &e->stages[2].mode);
504 get_tree_entry_if_blob(&b->object.oid, path,
505 &e->stages[3].oid, &e->stages[3].mode);
506 item = string_list_insert(entries, path);
507 item->util = e;
508 return e;
509 }
510
511 /*
512 * Create a dictionary mapping file names to stage_data objects. The
513 * dictionary contains one entry for every path with a non-zero stage entry.
514 */
515 static struct string_list *get_unmerged(void)
516 {
517 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
518 int i;
519
520 unmerged->strdup_strings = 1;
521
522 for (i = 0; i < active_nr; i++) {
523 struct string_list_item *item;
524 struct stage_data *e;
525 const struct cache_entry *ce = active_cache[i];
526 if (!ce_stage(ce))
527 continue;
528
529 item = string_list_lookup(unmerged, ce->name);
530 if (!item) {
531 item = string_list_insert(unmerged, ce->name);
532 item->util = xcalloc(1, sizeof(struct stage_data));
533 }
534 e = item->util;
535 e->stages[ce_stage(ce)].mode = ce->ce_mode;
536 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
537 }
538
539 return unmerged;
540 }
541
542 static int string_list_df_name_compare(const char *one, const char *two)
543 {
544 int onelen = strlen(one);
545 int twolen = strlen(two);
546 /*
547 * Here we only care that entries for D/F conflicts are
548 * adjacent, in particular with the file of the D/F conflict
549 * appearing before files below the corresponding directory.
550 * The order of the rest of the list is irrelevant for us.
551 *
552 * To achieve this, we sort with df_name_compare and provide
553 * the mode S_IFDIR so that D/F conflicts will sort correctly.
554 * We use the mode S_IFDIR for everything else for simplicity,
555 * since in other cases any changes in their order due to
556 * sorting cause no problems for us.
557 */
558 int cmp = df_name_compare(one, onelen, S_IFDIR,
559 two, twolen, S_IFDIR);
560 /*
561 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
562 * that 'foo' comes before 'foo/bar'.
563 */
564 if (cmp)
565 return cmp;
566 return onelen - twolen;
567 }
568
569 static void record_df_conflict_files(struct merge_options *o,
570 struct string_list *entries)
571 {
572 /* If there is a D/F conflict and the file for such a conflict
573 * currently exists in the working tree, we want to allow it to be
574 * removed to make room for the corresponding directory if needed.
575 * The files underneath the directories of such D/F conflicts will
576 * be processed before the corresponding file involved in the D/F
577 * conflict. If the D/F directory ends up being removed by the
578 * merge, then we won't have to touch the D/F file. If the D/F
579 * directory needs to be written to the working copy, then the D/F
580 * file will simply be removed (in make_room_for_path()) to make
581 * room for the necessary paths. Note that if both the directory
582 * and the file need to be present, then the D/F file will be
583 * reinstated with a new unique name at the time it is processed.
584 */
585 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
586 const char *last_file = NULL;
587 int last_len = 0;
588 int i;
589
590 /*
591 * If we're merging merge-bases, we don't want to bother with
592 * any working directory changes.
593 */
594 if (o->call_depth)
595 return;
596
597 /* Ensure D/F conflicts are adjacent in the entries list. */
598 for (i = 0; i < entries->nr; i++) {
599 struct string_list_item *next = &entries->items[i];
600 string_list_append(&df_sorted_entries, next->string)->util =
601 next->util;
602 }
603 df_sorted_entries.cmp = string_list_df_name_compare;
604 string_list_sort(&df_sorted_entries);
605
606 string_list_clear(&o->df_conflict_file_set, 1);
607 for (i = 0; i < df_sorted_entries.nr; i++) {
608 const char *path = df_sorted_entries.items[i].string;
609 int len = strlen(path);
610 struct stage_data *e = df_sorted_entries.items[i].util;
611
612 /*
613 * Check if last_file & path correspond to a D/F conflict;
614 * i.e. whether path is last_file+'/'+<something>.
615 * If so, record that it's okay to remove last_file to make
616 * room for path and friends if needed.
617 */
618 if (last_file &&
619 len > last_len &&
620 memcmp(path, last_file, last_len) == 0 &&
621 path[last_len] == '/') {
622 string_list_insert(&o->df_conflict_file_set, last_file);
623 }
624
625 /*
626 * Determine whether path could exist as a file in the
627 * working directory as a possible D/F conflict. This
628 * will only occur when it exists in stage 2 as a
629 * file.
630 */
631 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
632 last_file = path;
633 last_len = len;
634 } else {
635 last_file = NULL;
636 }
637 }
638 string_list_clear(&df_sorted_entries, 0);
639 }
640
641 struct rename {
642 struct diff_filepair *pair;
643 /*
644 * Purpose of src_entry and dst_entry:
645 *
646 * If 'before' is renamed to 'after' then src_entry will contain
647 * the versions of 'before' from the merge_base, HEAD, and MERGE in
648 * stages 1, 2, and 3; dst_entry will contain the respective
649 * versions of 'after' in corresponding locations. Thus, we have a
650 * total of six modes and oids, though some will be null. (Stage 0
651 * is ignored; we're interested in handling conflicts.)
652 *
653 * Since we don't turn on break-rewrites by default, neither
654 * src_entry nor dst_entry can have all three of their stages have
655 * non-null oids, meaning at most four of the six will be non-null.
656 * Also, since this is a rename, both src_entry and dst_entry will
657 * have at least one non-null oid, meaning at least two will be
658 * non-null. Of the six oids, a typical rename will have three be
659 * non-null. Only two implies a rename/delete, and four implies a
660 * rename/add.
661 */
662 struct stage_data *src_entry;
663 struct stage_data *dst_entry;
664 unsigned add_turned_into_rename:1;
665 unsigned processed:1;
666 };
667
668 static int update_stages(struct merge_options *opt, const char *path,
669 const struct diff_filespec *o,
670 const struct diff_filespec *a,
671 const struct diff_filespec *b)
672 {
673
674 /*
675 * NOTE: It is usually a bad idea to call update_stages on a path
676 * before calling update_file on that same path, since it can
677 * sometimes lead to spurious "refusing to lose untracked file..."
678 * messages from update_file (via make_room_for path via
679 * would_lose_untracked). Instead, reverse the order of the calls
680 * (executing update_file first and then update_stages).
681 */
682 int clear = 1;
683 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
684 if (clear)
685 if (remove_file_from_cache(path))
686 return -1;
687 if (o)
688 if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options))
689 return -1;
690 if (a)
691 if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options))
692 return -1;
693 if (b)
694 if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options))
695 return -1;
696 return 0;
697 }
698
699 static void update_entry(struct stage_data *entry,
700 struct diff_filespec *o,
701 struct diff_filespec *a,
702 struct diff_filespec *b)
703 {
704 entry->processed = 0;
705 entry->stages[1].mode = o->mode;
706 entry->stages[2].mode = a->mode;
707 entry->stages[3].mode = b->mode;
708 oidcpy(&entry->stages[1].oid, &o->oid);
709 oidcpy(&entry->stages[2].oid, &a->oid);
710 oidcpy(&entry->stages[3].oid, &b->oid);
711 }
712
713 static int remove_file(struct merge_options *o, int clean,
714 const char *path, int no_wd)
715 {
716 int update_cache = o->call_depth || clean;
717 int update_working_directory = !o->call_depth && !no_wd;
718
719 if (update_cache) {
720 if (remove_file_from_cache(path))
721 return -1;
722 }
723 if (update_working_directory) {
724 if (ignore_case) {
725 struct cache_entry *ce;
726 ce = cache_file_exists(path, strlen(path), ignore_case);
727 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
728 return 0;
729 }
730 if (remove_path(path))
731 return -1;
732 }
733 return 0;
734 }
735
736 /* add a string to a strbuf, but converting "/" to "_" */
737 static void add_flattened_path(struct strbuf *out, const char *s)
738 {
739 size_t i = out->len;
740 strbuf_addstr(out, s);
741 for (; i < out->len; i++)
742 if (out->buf[i] == '/')
743 out->buf[i] = '_';
744 }
745
746 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
747 {
748 struct path_hashmap_entry *entry;
749 struct strbuf newpath = STRBUF_INIT;
750 int suffix = 0;
751 size_t base_len;
752
753 strbuf_addf(&newpath, "%s~", path);
754 add_flattened_path(&newpath, branch);
755
756 base_len = newpath.len;
757 while (hashmap_get_from_hash(&o->current_file_dir_set,
758 path_hash(newpath.buf), newpath.buf) ||
759 (!o->call_depth && file_exists(newpath.buf))) {
760 strbuf_setlen(&newpath, base_len);
761 strbuf_addf(&newpath, "_%d", suffix++);
762 }
763
764 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
765 hashmap_entry_init(entry, path_hash(entry->path));
766 hashmap_add(&o->current_file_dir_set, entry);
767 return strbuf_detach(&newpath, NULL);
768 }
769
770 /**
771 * Check whether a directory in the index is in the way of an incoming
772 * file. Return 1 if so. If check_working_copy is non-zero, also
773 * check the working directory. If empty_ok is non-zero, also return
774 * 0 in the case where the working-tree dir exists but is empty.
775 */
776 static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
777 {
778 int pos;
779 struct strbuf dirpath = STRBUF_INIT;
780 struct stat st;
781
782 strbuf_addstr(&dirpath, path);
783 strbuf_addch(&dirpath, '/');
784
785 pos = cache_name_pos(dirpath.buf, dirpath.len);
786
787 if (pos < 0)
788 pos = -1 - pos;
789 if (pos < active_nr &&
790 !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) {
791 strbuf_release(&dirpath);
792 return 1;
793 }
794
795 strbuf_release(&dirpath);
796 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
797 !(empty_ok && is_empty_dir(path));
798 }
799
800 /*
801 * Returns whether path was tracked in the index before the merge started,
802 * and its oid and mode match the specified values
803 */
804 static int was_tracked_and_matches(struct merge_options *o, const char *path,
805 const struct object_id *oid, unsigned mode)
806 {
807 int pos = index_name_pos(&o->orig_index, path, strlen(path));
808 struct cache_entry *ce;
809
810 if (0 > pos)
811 /* we were not tracking this path before the merge */
812 return 0;
813
814 /* See if the file we were tracking before matches */
815 ce = o->orig_index.cache[pos];
816 return (oid_eq(&ce->oid, oid) && ce->ce_mode == mode);
817 }
818
819 /*
820 * Returns whether path was tracked in the index before the merge started
821 */
822 static int was_tracked(struct merge_options *o, const char *path)
823 {
824 int pos = index_name_pos(&o->orig_index, path, strlen(path));
825
826 if (0 <= pos)
827 /* we were tracking this path before the merge */
828 return 1;
829
830 return 0;
831 }
832
833 static int would_lose_untracked(const char *path)
834 {
835 /*
836 * This may look like it can be simplified to:
837 * return !was_tracked(o, path) && file_exists(path)
838 * but it can't. This function needs to know whether path was in
839 * the working tree due to EITHER having been tracked in the index
840 * before the merge OR having been put into the working copy and
841 * index by unpack_trees(). Due to that either-or requirement, we
842 * check the current index instead of the original one.
843 *
844 * Note that we do not need to worry about merge-recursive itself
845 * updating the index after unpack_trees() and before calling this
846 * function, because we strictly require all code paths in
847 * merge-recursive to update the working tree first and the index
848 * second. Doing otherwise would break
849 * update_file()/would_lose_untracked(); see every comment in this
850 * file which mentions "update_stages".
851 */
852 int pos = cache_name_pos(path, strlen(path));
853
854 if (pos < 0)
855 pos = -1 - pos;
856 while (pos < active_nr &&
857 !strcmp(path, active_cache[pos]->name)) {
858 /*
859 * If stage #0, it is definitely tracked.
860 * If it has stage #2 then it was tracked
861 * before this merge started. All other
862 * cases the path was not tracked.
863 */
864 switch (ce_stage(active_cache[pos])) {
865 case 0:
866 case 2:
867 return 0;
868 }
869 pos++;
870 }
871 return file_exists(path);
872 }
873
874 static int was_dirty(struct merge_options *o, const char *path)
875 {
876 struct cache_entry *ce;
877 int dirty = 1;
878
879 if (o->call_depth || !was_tracked(o, path))
880 return !dirty;
881
882 ce = index_file_exists(o->unpack_opts.src_index,
883 path, strlen(path), ignore_case);
884 dirty = verify_uptodate(ce, &o->unpack_opts) != 0;
885 return dirty;
886 }
887
888 static int make_room_for_path(struct merge_options *o, const char *path)
889 {
890 int status, i;
891 const char *msg = _("failed to create path '%s'%s");
892
893 /* Unlink any D/F conflict files that are in the way */
894 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
895 const char *df_path = o->df_conflict_file_set.items[i].string;
896 size_t pathlen = strlen(path);
897 size_t df_pathlen = strlen(df_path);
898 if (df_pathlen < pathlen &&
899 path[df_pathlen] == '/' &&
900 strncmp(path, df_path, df_pathlen) == 0) {
901 output(o, 3,
902 _("Removing %s to make room for subdirectory\n"),
903 df_path);
904 unlink(df_path);
905 unsorted_string_list_delete_item(&o->df_conflict_file_set,
906 i, 0);
907 break;
908 }
909 }
910
911 /* Make sure leading directories are created */
912 status = safe_create_leading_directories_const(path);
913 if (status) {
914 if (status == SCLD_EXISTS)
915 /* something else exists */
916 return err(o, msg, path, _(": perhaps a D/F conflict?"));
917 return err(o, msg, path, "");
918 }
919
920 /*
921 * Do not unlink a file in the work tree if we are not
922 * tracking it.
923 */
924 if (would_lose_untracked(path))
925 return err(o, _("refusing to lose untracked file at '%s'"),
926 path);
927
928 /* Successful unlink is good.. */
929 if (!unlink(path))
930 return 0;
931 /* .. and so is no existing file */
932 if (errno == ENOENT)
933 return 0;
934 /* .. but not some other error (who really cares what?) */
935 return err(o, msg, path, _(": perhaps a D/F conflict?"));
936 }
937
938 static int update_file_flags(struct merge_options *o,
939 const struct object_id *oid,
940 unsigned mode,
941 const char *path,
942 int update_cache,
943 int update_wd)
944 {
945 int ret = 0;
946
947 if (o->call_depth)
948 update_wd = 0;
949
950 if (update_wd) {
951 enum object_type type;
952 void *buf;
953 unsigned long size;
954
955 if (S_ISGITLINK(mode)) {
956 /*
957 * We may later decide to recursively descend into
958 * the submodule directory and update its index
959 * and/or work tree, but we do not do that now.
960 */
961 update_wd = 0;
962 goto update_index;
963 }
964
965 buf = read_object_file(oid, &type, &size);
966 if (!buf)
967 return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path);
968 if (type != OBJ_BLOB) {
969 ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path);
970 goto free_buf;
971 }
972 if (S_ISREG(mode)) {
973 struct strbuf strbuf = STRBUF_INIT;
974 if (convert_to_working_tree(&the_index, path, buf, size, &strbuf)) {
975 free(buf);
976 size = strbuf.len;
977 buf = strbuf_detach(&strbuf, NULL);
978 }
979 }
980
981 if (make_room_for_path(o, path) < 0) {
982 update_wd = 0;
983 goto free_buf;
984 }
985 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
986 int fd;
987 if (mode & 0100)
988 mode = 0777;
989 else
990 mode = 0666;
991 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
992 if (fd < 0) {
993 ret = err(o, _("failed to open '%s': %s"),
994 path, strerror(errno));
995 goto free_buf;
996 }
997 write_in_full(fd, buf, size);
998 close(fd);
999 } else if (S_ISLNK(mode)) {
1000 char *lnk = xmemdupz(buf, size);
1001 safe_create_leading_directories_const(path);
1002 unlink(path);
1003 if (symlink(lnk, path))
1004 ret = err(o, _("failed to symlink '%s': %s"),
1005 path, strerror(errno));
1006 free(lnk);
1007 } else
1008 ret = err(o,
1009 _("do not know what to do with %06o %s '%s'"),
1010 mode, oid_to_hex(oid), path);
1011 free_buf:
1012 free(buf);
1013 }
1014 update_index:
1015 if (!ret && update_cache)
1016 if (add_cacheinfo(o, mode, oid, path, 0, update_wd,
1017 ADD_CACHE_OK_TO_ADD))
1018 return -1;
1019 return ret;
1020 }
1021
1022 static int update_file(struct merge_options *o,
1023 int clean,
1024 const struct object_id *oid,
1025 unsigned mode,
1026 const char *path)
1027 {
1028 return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth);
1029 }
1030
1031 /* Low level file merging, update and removal */
1032
1033 struct merge_file_info {
1034 struct object_id oid;
1035 unsigned mode;
1036 unsigned clean:1,
1037 merge:1;
1038 };
1039
1040 static int merge_3way(struct merge_options *o,
1041 mmbuffer_t *result_buf,
1042 const struct diff_filespec *one,
1043 const struct diff_filespec *a,
1044 const struct diff_filespec *b,
1045 const char *branch1,
1046 const char *branch2,
1047 const int extra_marker_size)
1048 {
1049 mmfile_t orig, src1, src2;
1050 struct ll_merge_options ll_opts = {0};
1051 char *base_name, *name1, *name2;
1052 int merge_status;
1053
1054 ll_opts.renormalize = o->renormalize;
1055 ll_opts.extra_marker_size = extra_marker_size;
1056 ll_opts.xdl_opts = o->xdl_opts;
1057
1058 if (o->call_depth) {
1059 ll_opts.virtual_ancestor = 1;
1060 ll_opts.variant = 0;
1061 } else {
1062 switch (o->recursive_variant) {
1063 case MERGE_RECURSIVE_OURS:
1064 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
1065 break;
1066 case MERGE_RECURSIVE_THEIRS:
1067 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
1068 break;
1069 default:
1070 ll_opts.variant = 0;
1071 break;
1072 }
1073 }
1074
1075 if (strcmp(a->path, b->path) ||
1076 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
1077 base_name = o->ancestor == NULL ? NULL :
1078 mkpathdup("%s:%s", o->ancestor, one->path);
1079 name1 = mkpathdup("%s:%s", branch1, a->path);
1080 name2 = mkpathdup("%s:%s", branch2, b->path);
1081 } else {
1082 base_name = o->ancestor == NULL ? NULL :
1083 mkpathdup("%s", o->ancestor);
1084 name1 = mkpathdup("%s", branch1);
1085 name2 = mkpathdup("%s", branch2);
1086 }
1087
1088 read_mmblob(&orig, &one->oid);
1089 read_mmblob(&src1, &a->oid);
1090 read_mmblob(&src2, &b->oid);
1091
1092 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
1093 &src1, name1, &src2, name2,
1094 &the_index, &ll_opts);
1095
1096 free(base_name);
1097 free(name1);
1098 free(name2);
1099 free(orig.ptr);
1100 free(src1.ptr);
1101 free(src2.ptr);
1102 return merge_status;
1103 }
1104
1105 static int find_first_merges(struct object_array *result, const char *path,
1106 struct commit *a, struct commit *b)
1107 {
1108 int i, j;
1109 struct object_array merges = OBJECT_ARRAY_INIT;
1110 struct commit *commit;
1111 int contains_another;
1112
1113 char merged_revision[42];
1114 const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1115 "--all", merged_revision, NULL };
1116 struct rev_info revs;
1117 struct setup_revision_opt rev_opts;
1118
1119 memset(result, 0, sizeof(struct object_array));
1120 memset(&rev_opts, 0, sizeof(rev_opts));
1121
1122 /* get all revisions that merge commit a */
1123 xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1124 oid_to_hex(&a->object.oid));
1125 repo_init_revisions(the_repository, &revs, NULL);
1126 rev_opts.submodule = path;
1127 /* FIXME: can't handle linked worktrees in submodules yet */
1128 revs.single_worktree = path != NULL;
1129 setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1130
1131 /* save all revisions from the above list that contain b */
1132 if (prepare_revision_walk(&revs))
1133 die("revision walk setup failed");
1134 while ((commit = get_revision(&revs)) != NULL) {
1135 struct object *o = &(commit->object);
1136 if (in_merge_bases(b, commit))
1137 add_object_array(o, NULL, &merges);
1138 }
1139 reset_revision_walk();
1140
1141 /* Now we've got all merges that contain a and b. Prune all
1142 * merges that contain another found merge and save them in
1143 * result.
1144 */
1145 for (i = 0; i < merges.nr; i++) {
1146 struct commit *m1 = (struct commit *) merges.objects[i].item;
1147
1148 contains_another = 0;
1149 for (j = 0; j < merges.nr; j++) {
1150 struct commit *m2 = (struct commit *) merges.objects[j].item;
1151 if (i != j && in_merge_bases(m2, m1)) {
1152 contains_another = 1;
1153 break;
1154 }
1155 }
1156
1157 if (!contains_another)
1158 add_object_array(merges.objects[i].item, NULL, result);
1159 }
1160
1161 object_array_clear(&merges);
1162 return result->nr;
1163 }
1164
1165 static void print_commit(struct commit *commit)
1166 {
1167 struct strbuf sb = STRBUF_INIT;
1168 struct pretty_print_context ctx = {0};
1169 ctx.date_mode.type = DATE_NORMAL;
1170 format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1171 fprintf(stderr, "%s\n", sb.buf);
1172 strbuf_release(&sb);
1173 }
1174
1175 static int merge_submodule(struct merge_options *o,
1176 struct object_id *result, const char *path,
1177 const struct object_id *base, const struct object_id *a,
1178 const struct object_id *b)
1179 {
1180 struct commit *commit_base, *commit_a, *commit_b;
1181 int parent_count;
1182 struct object_array merges;
1183
1184 int i;
1185 int search = !o->call_depth;
1186
1187 /* store a in result in case we fail */
1188 oidcpy(result, a);
1189
1190 /* we can not handle deletion conflicts */
1191 if (is_null_oid(base))
1192 return 0;
1193 if (is_null_oid(a))
1194 return 0;
1195 if (is_null_oid(b))
1196 return 0;
1197
1198 if (add_submodule_odb(path)) {
1199 output(o, 1, _("Failed to merge submodule %s (not checked out)"), path);
1200 return 0;
1201 }
1202
1203 if (!(commit_base = lookup_commit_reference(the_repository, base)) ||
1204 !(commit_a = lookup_commit_reference(the_repository, a)) ||
1205 !(commit_b = lookup_commit_reference(the_repository, b))) {
1206 output(o, 1, _("Failed to merge submodule %s (commits not present)"), path);
1207 return 0;
1208 }
1209
1210 /* check whether both changes are forward */
1211 if (!in_merge_bases(commit_base, commit_a) ||
1212 !in_merge_bases(commit_base, commit_b)) {
1213 output(o, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
1214 return 0;
1215 }
1216
1217 /* Case #1: a is contained in b or vice versa */
1218 if (in_merge_bases(commit_a, commit_b)) {
1219 oidcpy(result, b);
1220 if (show(o, 3)) {
1221 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1222 output_commit_title(o, commit_b);
1223 } else if (show(o, 2))
1224 output(o, 2, _("Fast-forwarding submodule %s"), path);
1225 else
1226 ; /* no output */
1227
1228 return 1;
1229 }
1230 if (in_merge_bases(commit_b, commit_a)) {
1231 oidcpy(result, a);
1232 if (show(o, 3)) {
1233 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1234 output_commit_title(o, commit_a);
1235 } else if (show(o, 2))
1236 output(o, 2, _("Fast-forwarding submodule %s"), path);
1237 else
1238 ; /* no output */
1239
1240 return 1;
1241 }
1242
1243 /*
1244 * Case #2: There are one or more merges that contain a and b in
1245 * the submodule. If there is only one, then present it as a
1246 * suggestion to the user, but leave it marked unmerged so the
1247 * user needs to confirm the resolution.
1248 */
1249
1250 /* Skip the search if makes no sense to the calling context. */
1251 if (!search)
1252 return 0;
1253
1254 /* find commit which merges them */
1255 parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1256 switch (parent_count) {
1257 case 0:
1258 output(o, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
1259 break;
1260
1261 case 1:
1262 output(o, 1, _("Failed to merge submodule %s (not fast-forward)"), path);
1263 output(o, 2, _("Found a possible merge resolution for the submodule:\n"));
1264 print_commit((struct commit *) merges.objects[0].item);
1265 output(o, 2, _(
1266 "If this is correct simply add it to the index "
1267 "for example\n"
1268 "by using:\n\n"
1269 " git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1270 "which will accept this suggestion.\n"),
1271 oid_to_hex(&merges.objects[0].item->oid), path);
1272 break;
1273
1274 default:
1275 output(o, 1, _("Failed to merge submodule %s (multiple merges found)"), path);
1276 for (i = 0; i < merges.nr; i++)
1277 print_commit((struct commit *) merges.objects[i].item);
1278 }
1279
1280 object_array_clear(&merges);
1281 return 0;
1282 }
1283
1284 static int merge_mode_and_contents(struct merge_options *o,
1285 const struct diff_filespec *one,
1286 const struct diff_filespec *a,
1287 const struct diff_filespec *b,
1288 const char *filename,
1289 const char *branch1,
1290 const char *branch2,
1291 const int extra_marker_size,
1292 struct merge_file_info *result)
1293 {
1294 if (o->branch1 != branch1) {
1295 /*
1296 * It's weird getting a reverse merge with HEAD on the bottom
1297 * side of the conflict markers and the other branch on the
1298 * top. Fix that.
1299 */
1300 return merge_mode_and_contents(o, one, b, a,
1301 filename,
1302 branch2, branch1,
1303 extra_marker_size, result);
1304 }
1305
1306 result->merge = 0;
1307 result->clean = 1;
1308
1309 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
1310 result->clean = 0;
1311 if (S_ISREG(a->mode)) {
1312 result->mode = a->mode;
1313 oidcpy(&result->oid, &a->oid);
1314 } else {
1315 result->mode = b->mode;
1316 oidcpy(&result->oid, &b->oid);
1317 }
1318 } else {
1319 if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid))
1320 result->merge = 1;
1321
1322 /*
1323 * Merge modes
1324 */
1325 if (a->mode == b->mode || a->mode == one->mode)
1326 result->mode = b->mode;
1327 else {
1328 result->mode = a->mode;
1329 if (b->mode != one->mode) {
1330 result->clean = 0;
1331 result->merge = 1;
1332 }
1333 }
1334
1335 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid))
1336 oidcpy(&result->oid, &b->oid);
1337 else if (oid_eq(&b->oid, &one->oid))
1338 oidcpy(&result->oid, &a->oid);
1339 else if (S_ISREG(a->mode)) {
1340 mmbuffer_t result_buf;
1341 int ret = 0, merge_status;
1342
1343 merge_status = merge_3way(o, &result_buf, one, a, b,
1344 branch1, branch2,
1345 extra_marker_size);
1346
1347 if ((merge_status < 0) || !result_buf.ptr)
1348 ret = err(o, _("Failed to execute internal merge"));
1349
1350 if (!ret &&
1351 write_object_file(result_buf.ptr, result_buf.size,
1352 blob_type, &result->oid))
1353 ret = err(o, _("Unable to add %s to database"),
1354 a->path);
1355
1356 free(result_buf.ptr);
1357 if (ret)
1358 return ret;
1359 result->clean = (merge_status == 0);
1360 } else if (S_ISGITLINK(a->mode)) {
1361 result->clean = merge_submodule(o, &result->oid,
1362 one->path,
1363 &one->oid,
1364 &a->oid,
1365 &b->oid);
1366 } else if (S_ISLNK(a->mode)) {
1367 switch (o->recursive_variant) {
1368 case MERGE_RECURSIVE_NORMAL:
1369 oidcpy(&result->oid, &a->oid);
1370 if (!oid_eq(&a->oid, &b->oid))
1371 result->clean = 0;
1372 break;
1373 case MERGE_RECURSIVE_OURS:
1374 oidcpy(&result->oid, &a->oid);
1375 break;
1376 case MERGE_RECURSIVE_THEIRS:
1377 oidcpy(&result->oid, &b->oid);
1378 break;
1379 }
1380 } else
1381 BUG("unsupported object type in the tree");
1382 }
1383
1384 if (result->merge)
1385 output(o, 2, _("Auto-merging %s"), filename);
1386
1387 return 0;
1388 }
1389
1390 static int handle_rename_via_dir(struct merge_options *o,
1391 struct diff_filepair *pair,
1392 const char *rename_branch,
1393 const char *other_branch)
1394 {
1395 /*
1396 * Handle file adds that need to be renamed due to directory rename
1397 * detection. This differs from handle_rename_normal, because
1398 * there is no content merge to do; just move the file into the
1399 * desired final location.
1400 */
1401 const struct diff_filespec *dest = pair->two;
1402
1403 if (!o->call_depth && would_lose_untracked(dest->path)) {
1404 char *alt_path = unique_path(o, dest->path, rename_branch);
1405
1406 output(o, 1, _("Error: Refusing to lose untracked file at %s; "
1407 "writing to %s instead."),
1408 dest->path, alt_path);
1409 /*
1410 * Write the file in worktree at alt_path, but not in the
1411 * index. Instead, write to dest->path for the index but
1412 * only at the higher appropriate stage.
1413 */
1414 if (update_file(o, 0, &dest->oid, dest->mode, alt_path))
1415 return -1;
1416 free(alt_path);
1417 return update_stages(o, dest->path, NULL,
1418 rename_branch == o->branch1 ? dest : NULL,
1419 rename_branch == o->branch1 ? NULL : dest);
1420 }
1421
1422 /* Update dest->path both in index and in worktree */
1423 if (update_file(o, 1, &dest->oid, dest->mode, dest->path))
1424 return -1;
1425 return 0;
1426 }
1427
1428 static int handle_change_delete(struct merge_options *o,
1429 const char *path, const char *old_path,
1430 const struct object_id *o_oid, int o_mode,
1431 const struct object_id *changed_oid,
1432 int changed_mode,
1433 const char *change_branch,
1434 const char *delete_branch,
1435 const char *change, const char *change_past)
1436 {
1437 char *alt_path = NULL;
1438 const char *update_path = path;
1439 int ret = 0;
1440
1441 if (dir_in_way(path, !o->call_depth, 0) ||
1442 (!o->call_depth && would_lose_untracked(path))) {
1443 update_path = alt_path = unique_path(o, path, change_branch);
1444 }
1445
1446 if (o->call_depth) {
1447 /*
1448 * We cannot arbitrarily accept either a_sha or b_sha as
1449 * correct; since there is no true "middle point" between
1450 * them, simply reuse the base version for virtual merge base.
1451 */
1452 ret = remove_file_from_cache(path);
1453 if (!ret)
1454 ret = update_file(o, 0, o_oid, o_mode, update_path);
1455 } else {
1456 /*
1457 * Despite the four nearly duplicate messages and argument
1458 * lists below and the ugliness of the nested if-statements,
1459 * having complete messages makes the job easier for
1460 * translators.
1461 *
1462 * The slight variance among the cases is due to the fact
1463 * that:
1464 * 1) directory/file conflicts (in effect if
1465 * !alt_path) could cause us to need to write the
1466 * file to a different path.
1467 * 2) renames (in effect if !old_path) could mean that
1468 * there are two names for the path that the user
1469 * may know the file by.
1470 */
1471 if (!alt_path) {
1472 if (!old_path) {
1473 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1474 "and %s in %s. Version %s of %s left in tree."),
1475 change, path, delete_branch, change_past,
1476 change_branch, change_branch, path);
1477 } else {
1478 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1479 "and %s to %s in %s. Version %s of %s left in tree."),
1480 change, old_path, delete_branch, change_past, path,
1481 change_branch, change_branch, path);
1482 }
1483 } else {
1484 if (!old_path) {
1485 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1486 "and %s in %s. Version %s of %s left in tree at %s."),
1487 change, path, delete_branch, change_past,
1488 change_branch, change_branch, path, alt_path);
1489 } else {
1490 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1491 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1492 change, old_path, delete_branch, change_past, path,
1493 change_branch, change_branch, path, alt_path);
1494 }
1495 }
1496 /*
1497 * No need to call update_file() on path when change_branch ==
1498 * o->branch1 && !alt_path, since that would needlessly touch
1499 * path. We could call update_file_flags() with update_cache=0
1500 * and update_wd=0, but that's a no-op.
1501 */
1502 if (change_branch != o->branch1 || alt_path)
1503 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1504 }
1505 free(alt_path);
1506
1507 return ret;
1508 }
1509
1510 static int handle_rename_delete(struct merge_options *o,
1511 struct diff_filepair *pair,
1512 const char *rename_branch,
1513 const char *delete_branch)
1514 {
1515 const struct diff_filespec *orig = pair->one;
1516 const struct diff_filespec *dest = pair->two;
1517
1518 if (handle_change_delete(o,
1519 o->call_depth ? orig->path : dest->path,
1520 o->call_depth ? NULL : orig->path,
1521 &orig->oid, orig->mode,
1522 &dest->oid, dest->mode,
1523 rename_branch, delete_branch,
1524 _("rename"), _("renamed")))
1525 return -1;
1526
1527 if (o->call_depth)
1528 return remove_file_from_cache(dest->path);
1529 else
1530 return update_stages(o, dest->path, NULL,
1531 rename_branch == o->branch1 ? dest : NULL,
1532 rename_branch == o->branch1 ? NULL : dest);
1533 }
1534
1535 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1536 struct stage_data *entry,
1537 int stage)
1538 {
1539 struct object_id *oid = &entry->stages[stage].oid;
1540 unsigned mode = entry->stages[stage].mode;
1541 if (mode == 0 || is_null_oid(oid))
1542 return NULL;
1543 oidcpy(&target->oid, oid);
1544 target->mode = mode;
1545 return target;
1546 }
1547
1548 static int handle_file_collision(struct merge_options *o,
1549 const char *collide_path,
1550 const char *prev_path1,
1551 const char *prev_path2,
1552 const char *branch1, const char *branch2,
1553 const struct object_id *a_oid,
1554 unsigned int a_mode,
1555 const struct object_id *b_oid,
1556 unsigned int b_mode)
1557 {
1558 struct merge_file_info mfi;
1559 struct diff_filespec null, a, b;
1560 char *alt_path = NULL;
1561 const char *update_path = collide_path;
1562
1563 /*
1564 * It's easiest to get the correct things into stage 2 and 3, and
1565 * to make sure that the content merge puts HEAD before the other
1566 * branch if we just ensure that branch1 == o->branch1. So, simply
1567 * flip arguments around if we don't have that.
1568 */
1569 if (branch1 != o->branch1) {
1570 return handle_file_collision(o, collide_path,
1571 prev_path2, prev_path1,
1572 branch2, branch1,
1573 b_oid, b_mode,
1574 a_oid, a_mode);
1575 }
1576
1577 /*
1578 * In the recursive case, we just opt to undo renames
1579 */
1580 if (o->call_depth && (prev_path1 || prev_path2)) {
1581 /* Put first file (a_oid, a_mode) in its original spot */
1582 if (prev_path1) {
1583 if (update_file(o, 1, a_oid, a_mode, prev_path1))
1584 return -1;
1585 } else {
1586 if (update_file(o, 1, a_oid, a_mode, collide_path))
1587 return -1;
1588 }
1589
1590 /* Put second file (b_oid, b_mode) in its original spot */
1591 if (prev_path2) {
1592 if (update_file(o, 1, b_oid, b_mode, prev_path2))
1593 return -1;
1594 } else {
1595 if (update_file(o, 1, b_oid, b_mode, collide_path))
1596 return -1;
1597 }
1598
1599 /* Don't leave something at collision path if unrenaming both */
1600 if (prev_path1 && prev_path2)
1601 remove_file(o, 1, collide_path, 0);
1602
1603 return 0;
1604 }
1605
1606 /* Remove rename sources if rename/add or rename/rename(2to1) */
1607 if (prev_path1)
1608 remove_file(o, 1, prev_path1,
1609 o->call_depth || would_lose_untracked(prev_path1));
1610 if (prev_path2)
1611 remove_file(o, 1, prev_path2,
1612 o->call_depth || would_lose_untracked(prev_path2));
1613
1614 /*
1615 * Remove the collision path, if it wouldn't cause dirty contents
1616 * or an untracked file to get lost. We'll either overwrite with
1617 * merged contents, or just write out to differently named files.
1618 */
1619 if (was_dirty(o, collide_path)) {
1620 output(o, 1, _("Refusing to lose dirty file at %s"),
1621 collide_path);
1622 update_path = alt_path = unique_path(o, collide_path, "merged");
1623 } else if (would_lose_untracked(collide_path)) {
1624 /*
1625 * Only way we get here is if both renames were from
1626 * a directory rename AND user had an untracked file
1627 * at the location where both files end up after the
1628 * two directory renames. See testcase 10d of t6043.
1629 */
1630 output(o, 1, _("Refusing to lose untracked file at "
1631 "%s, even though it's in the way."),
1632 collide_path);
1633 update_path = alt_path = unique_path(o, collide_path, "merged");
1634 } else {
1635 /*
1636 * FIXME: It's possible that the two files are identical
1637 * and that the current working copy happens to match, in
1638 * which case we are unnecessarily touching the working
1639 * tree file. It's not a likely enough scenario that I
1640 * want to code up the checks for it and a better fix is
1641 * available if we restructure how unpack_trees() and
1642 * merge-recursive interoperate anyway, so punting for
1643 * now...
1644 */
1645 remove_file(o, 0, collide_path, 0);
1646 }
1647
1648 /* Store things in diff_filespecs for functions that need it */
1649 memset(&a, 0, sizeof(struct diff_filespec));
1650 memset(&b, 0, sizeof(struct diff_filespec));
1651 null.path = a.path = b.path = (char *)collide_path;
1652 oidcpy(&null.oid, &null_oid);
1653 null.mode = 0;
1654 oidcpy(&a.oid, a_oid);
1655 a.mode = a_mode;
1656 a.oid_valid = 1;
1657 oidcpy(&b.oid, b_oid);
1658 b.mode = b_mode;
1659 b.oid_valid = 1;
1660
1661 if (merge_mode_and_contents(o, &null, &a, &b, collide_path,
1662 branch1, branch2, o->call_depth * 2, &mfi))
1663 return -1;
1664 mfi.clean &= !alt_path;
1665 if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, update_path))
1666 return -1;
1667 if (!mfi.clean && !o->call_depth &&
1668 update_stages(o, collide_path, NULL, &a, &b))
1669 return -1;
1670 free(alt_path);
1671 /*
1672 * FIXME: If both a & b both started with conflicts (only possible
1673 * if they came from a rename/rename(2to1)), but had IDENTICAL
1674 * contents including those conflicts, then in the next line we claim
1675 * it was clean. If someone cares about this case, we should have the
1676 * caller notify us if we started with conflicts.
1677 */
1678 return mfi.clean;
1679 }
1680
1681 static int handle_rename_add(struct merge_options *o,
1682 struct rename_conflict_info *ci)
1683 {
1684 /* a was renamed to c, and a separate c was added. */
1685 struct diff_filespec *a = ci->pair1->one;
1686 struct diff_filespec *c = ci->pair1->two;
1687 char *path = c->path;
1688 char *prev_path_desc;
1689 struct merge_file_info mfi;
1690
1691 int other_stage = (ci->branch1 == o->branch1 ? 3 : 2);
1692
1693 output(o, 1, _("CONFLICT (rename/add): "
1694 "Rename %s->%s in %s. Added %s in %s"),
1695 a->path, c->path, ci->branch1,
1696 c->path, ci->branch2);
1697
1698 prev_path_desc = xstrfmt("version of %s from %s", path, a->path);
1699 if (merge_mode_and_contents(o, a, c, &ci->ren1_other, prev_path_desc,
1700 o->branch1, o->branch2,
1701 1 + o->call_depth * 2, &mfi))
1702 return -1;
1703 free(prev_path_desc);
1704
1705 return handle_file_collision(o,
1706 c->path, a->path, NULL,
1707 ci->branch1, ci->branch2,
1708 &mfi.oid, mfi.mode,
1709 &ci->dst_entry1->stages[other_stage].oid,
1710 ci->dst_entry1->stages[other_stage].mode);
1711 }
1712
1713 static char *find_path_for_conflict(struct merge_options *o,
1714 const char *path,
1715 const char *branch1,
1716 const char *branch2)
1717 {
1718 char *new_path = NULL;
1719 if (dir_in_way(path, !o->call_depth, 0)) {
1720 new_path = unique_path(o, path, branch1);
1721 output(o, 1, _("%s is a directory in %s adding "
1722 "as %s instead"),
1723 path, branch2, new_path);
1724 } else if (would_lose_untracked(path)) {
1725 new_path = unique_path(o, path, branch1);
1726 output(o, 1, _("Refusing to lose untracked file"
1727 " at %s; adding as %s instead"),
1728 path, new_path);
1729 }
1730
1731 return new_path;
1732 }
1733
1734 static int handle_rename_rename_1to2(struct merge_options *o,
1735 struct rename_conflict_info *ci)
1736 {
1737 /* One file was renamed in both branches, but to different names. */
1738 struct merge_file_info mfi;
1739 struct diff_filespec other;
1740 struct diff_filespec *add;
1741 struct diff_filespec *one = ci->pair1->one;
1742 struct diff_filespec *a = ci->pair1->two;
1743 struct diff_filespec *b = ci->pair2->two;
1744 char *path_desc;
1745
1746 output(o, 1, _("CONFLICT (rename/rename): "
1747 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1748 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1749 one->path, a->path, ci->branch1,
1750 one->path, b->path, ci->branch2,
1751 o->call_depth ? _(" (left unresolved)") : "");
1752
1753 path_desc = xstrfmt("%s and %s, both renamed from %s",
1754 a->path, b->path, one->path);
1755 if (merge_mode_and_contents(o, one, a, b, path_desc,
1756 ci->branch1, ci->branch2,
1757 o->call_depth * 2, &mfi))
1758 return -1;
1759 free(path_desc);
1760
1761 if (o->call_depth) {
1762 /*
1763 * FIXME: For rename/add-source conflicts (if we could detect
1764 * such), this is wrong. We should instead find a unique
1765 * pathname and then either rename the add-source file to that
1766 * unique path, or use that unique path instead of src here.
1767 */
1768 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1769 return -1;
1770
1771 /*
1772 * Above, we put the merged content at the merge-base's
1773 * path. Now we usually need to delete both a->path and
1774 * b->path. However, the rename on each side of the merge
1775 * could also be involved in a rename/add conflict. In
1776 * such cases, we should keep the added file around,
1777 * resolving the conflict at that path in its favor.
1778 */
1779 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1780 if (add) {
1781 if (update_file(o, 0, &add->oid, add->mode, a->path))
1782 return -1;
1783 }
1784 else
1785 remove_file_from_cache(a->path);
1786 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1787 if (add) {
1788 if (update_file(o, 0, &add->oid, add->mode, b->path))
1789 return -1;
1790 }
1791 else
1792 remove_file_from_cache(b->path);
1793 } else {
1794 /*
1795 * For each destination path, we need to see if there is a
1796 * rename/add collision. If not, we can write the file out
1797 * to the specified location.
1798 */
1799 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1800 if (add) {
1801 if (handle_file_collision(o, a->path,
1802 NULL, NULL,
1803 ci->branch1, ci->branch2,
1804 &mfi.oid, mfi.mode,
1805 &add->oid, add->mode) < 0)
1806 return -1;
1807 } else {
1808 char *new_path = find_path_for_conflict(o, a->path,
1809 ci->branch1,
1810 ci->branch2);
1811 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path ? new_path : a->path))
1812 return -1;
1813 free(new_path);
1814 if (update_stages(o, a->path, NULL, a, NULL))
1815 return -1;
1816 }
1817
1818 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1819 if (add) {
1820 if (handle_file_collision(o, b->path,
1821 NULL, NULL,
1822 ci->branch1, ci->branch2,
1823 &add->oid, add->mode,
1824 &mfi.oid, mfi.mode) < 0)
1825 return -1;
1826 } else {
1827 char *new_path = find_path_for_conflict(o, b->path,
1828 ci->branch2,
1829 ci->branch1);
1830 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path ? new_path : b->path))
1831 return -1;
1832 free(new_path);
1833 if (update_stages(o, b->path, NULL, NULL, b))
1834 return -1;
1835 }
1836 }
1837
1838 return 0;
1839 }
1840
1841 static int handle_rename_rename_2to1(struct merge_options *o,
1842 struct rename_conflict_info *ci)
1843 {
1844 /* Two files, a & b, were renamed to the same thing, c. */
1845 struct diff_filespec *a = ci->pair1->one;
1846 struct diff_filespec *b = ci->pair2->one;
1847 struct diff_filespec *c1 = ci->pair1->two;
1848 struct diff_filespec *c2 = ci->pair2->two;
1849 char *path = c1->path; /* == c2->path */
1850 char *path_side_1_desc;
1851 char *path_side_2_desc;
1852 struct merge_file_info mfi_c1;
1853 struct merge_file_info mfi_c2;
1854
1855 output(o, 1, _("CONFLICT (rename/rename): "
1856 "Rename %s->%s in %s. "
1857 "Rename %s->%s in %s"),
1858 a->path, c1->path, ci->branch1,
1859 b->path, c2->path, ci->branch2);
1860
1861 path_side_1_desc = xstrfmt("version of %s from %s", path, a->path);
1862 path_side_2_desc = xstrfmt("version of %s from %s", path, b->path);
1863 if (merge_mode_and_contents(o, a, c1, &ci->ren1_other, path_side_1_desc,
1864 o->branch1, o->branch2,
1865 1 + o->call_depth * 2, &mfi_c1) ||
1866 merge_mode_and_contents(o, b, &ci->ren2_other, c2, path_side_2_desc,
1867 o->branch1, o->branch2,
1868 1 + o->call_depth * 2, &mfi_c2))
1869 return -1;
1870 free(path_side_1_desc);
1871 free(path_side_2_desc);
1872
1873 return handle_file_collision(o, path, a->path, b->path,
1874 ci->branch1, ci->branch2,
1875 &mfi_c1.oid, mfi_c1.mode,
1876 &mfi_c2.oid, mfi_c2.mode);
1877 }
1878
1879 /*
1880 * Get the diff_filepairs changed between o_tree and tree.
1881 */
1882 static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
1883 struct tree *o_tree,
1884 struct tree *tree)
1885 {
1886 struct diff_queue_struct *ret;
1887 struct diff_options opts;
1888
1889 repo_diff_setup(the_repository, &opts);
1890 opts.flags.recursive = 1;
1891 opts.flags.rename_empty = 0;
1892 opts.detect_rename = merge_detect_rename(o);
1893 /*
1894 * We do not have logic to handle the detection of copies. In
1895 * fact, it may not even make sense to add such logic: would we
1896 * really want a change to a base file to be propagated through
1897 * multiple other files by a merge?
1898 */
1899 if (opts.detect_rename > DIFF_DETECT_RENAME)
1900 opts.detect_rename = DIFF_DETECT_RENAME;
1901 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
1902 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
1903 1000;
1904 opts.rename_score = o->rename_score;
1905 opts.show_rename_progress = o->show_rename_progress;
1906 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1907 diff_setup_done(&opts);
1908 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1909 diffcore_std(&opts);
1910 if (opts.needed_rename_limit > o->needed_rename_limit)
1911 o->needed_rename_limit = opts.needed_rename_limit;
1912
1913 ret = xmalloc(sizeof(*ret));
1914 *ret = diff_queued_diff;
1915
1916 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1917 diff_queued_diff.nr = 0;
1918 diff_queued_diff.queue = NULL;
1919 diff_flush(&opts);
1920 return ret;
1921 }
1922
1923 static int tree_has_path(struct tree *tree, const char *path)
1924 {
1925 struct object_id hashy;
1926 unsigned int mode_o;
1927
1928 return !get_tree_entry(&tree->object.oid, path,
1929 &hashy, &mode_o);
1930 }
1931
1932 /*
1933 * Return a new string that replaces the beginning portion (which matches
1934 * entry->dir), with entry->new_dir. In perl-speak:
1935 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1936 * NOTE:
1937 * Caller must ensure that old_path starts with entry->dir + '/'.
1938 */
1939 static char *apply_dir_rename(struct dir_rename_entry *entry,
1940 const char *old_path)
1941 {
1942 struct strbuf new_path = STRBUF_INIT;
1943 int oldlen, newlen;
1944
1945 if (entry->non_unique_new_dir)
1946 return NULL;
1947
1948 oldlen = strlen(entry->dir);
1949 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1950 strbuf_grow(&new_path, newlen);
1951 strbuf_addbuf(&new_path, &entry->new_dir);
1952 strbuf_addstr(&new_path, &old_path[oldlen]);
1953
1954 return strbuf_detach(&new_path, NULL);
1955 }
1956
1957 static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1958 char **old_dir, char **new_dir)
1959 {
1960 char *end_of_old, *end_of_new;
1961 int old_len, new_len;
1962
1963 *old_dir = NULL;
1964 *new_dir = NULL;
1965
1966 /*
1967 * For
1968 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1969 * the "e/foo.c" part is the same, we just want to know that
1970 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1971 * so, for this example, this function returns "a/b/c/d" in
1972 * *old_dir and "a/b/some/thing/else" in *new_dir.
1973 *
1974 * Also, if the basename of the file changed, we don't care. We
1975 * want to know which portion of the directory, if any, changed.
1976 */
1977 end_of_old = strrchr(old_path, '/');
1978 end_of_new = strrchr(new_path, '/');
1979
1980 if (end_of_old == NULL || end_of_new == NULL)
1981 return;
1982 while (*--end_of_new == *--end_of_old &&
1983 end_of_old != old_path &&
1984 end_of_new != new_path)
1985 ; /* Do nothing; all in the while loop */
1986 /*
1987 * We've found the first non-matching character in the directory
1988 * paths. That means the current directory we were comparing
1989 * represents the rename. Move end_of_old and end_of_new back
1990 * to the full directory name.
1991 */
1992 if (*end_of_old == '/')
1993 end_of_old++;
1994 if (*end_of_old != '/')
1995 end_of_new++;
1996 end_of_old = strchr(end_of_old, '/');
1997 end_of_new = strchr(end_of_new, '/');
1998
1999 /*
2000 * It may have been the case that old_path and new_path were the same
2001 * directory all along. Don't claim a rename if they're the same.
2002 */
2003 old_len = end_of_old - old_path;
2004 new_len = end_of_new - new_path;
2005
2006 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
2007 *old_dir = xstrndup(old_path, old_len);
2008 *new_dir = xstrndup(new_path, new_len);
2009 }
2010 }
2011
2012 static void remove_hashmap_entries(struct hashmap *dir_renames,
2013 struct string_list *items_to_remove)
2014 {
2015 int i;
2016 struct dir_rename_entry *entry;
2017
2018 for (i = 0; i < items_to_remove->nr; i++) {
2019 entry = items_to_remove->items[i].util;
2020 hashmap_remove(dir_renames, entry, NULL);
2021 }
2022 string_list_clear(items_to_remove, 0);
2023 }
2024
2025 /*
2026 * See if there is a directory rename for path, and if there are any file
2027 * level conflicts for the renamed location. If there is a rename and
2028 * there are no conflicts, return the new name. Otherwise, return NULL.
2029 */
2030 static char *handle_path_level_conflicts(struct merge_options *o,
2031 const char *path,
2032 struct dir_rename_entry *entry,
2033 struct hashmap *collisions,
2034 struct tree *tree)
2035 {
2036 char *new_path = NULL;
2037 struct collision_entry *collision_ent;
2038 int clean = 1;
2039 struct strbuf collision_paths = STRBUF_INIT;
2040
2041 /*
2042 * entry has the mapping of old directory name to new directory name
2043 * that we want to apply to path.
2044 */
2045 new_path = apply_dir_rename(entry, path);
2046
2047 if (!new_path) {
2048 /* This should only happen when entry->non_unique_new_dir set */
2049 if (!entry->non_unique_new_dir)
2050 BUG("entry->non_unqiue_dir not set and !new_path");
2051 output(o, 1, _("CONFLICT (directory rename split): "
2052 "Unclear where to place %s because directory "
2053 "%s was renamed to multiple other directories, "
2054 "with no destination getting a majority of the "
2055 "files."),
2056 path, entry->dir);
2057 clean = 0;
2058 return NULL;
2059 }
2060
2061 /*
2062 * The caller needs to have ensured that it has pre-populated
2063 * collisions with all paths that map to new_path. Do a quick check
2064 * to ensure that's the case.
2065 */
2066 collision_ent = collision_find_entry(collisions, new_path);
2067 if (collision_ent == NULL)
2068 BUG("collision_ent is NULL");
2069
2070 /*
2071 * Check for one-sided add/add/.../add conflicts, i.e.
2072 * where implicit renames from the other side doing
2073 * directory rename(s) can affect this side of history
2074 * to put multiple paths into the same location. Warn
2075 * and bail on directory renames for such paths.
2076 */
2077 if (collision_ent->reported_already) {
2078 clean = 0;
2079 } else if (tree_has_path(tree, new_path)) {
2080 collision_ent->reported_already = 1;
2081 strbuf_add_separated_string_list(&collision_paths, ", ",
2082 &collision_ent->source_files);
2083 output(o, 1, _("CONFLICT (implicit dir rename): Existing "
2084 "file/dir at %s in the way of implicit "
2085 "directory rename(s) putting the following "
2086 "path(s) there: %s."),
2087 new_path, collision_paths.buf);
2088 clean = 0;
2089 } else if (collision_ent->source_files.nr > 1) {
2090 collision_ent->reported_already = 1;
2091 strbuf_add_separated_string_list(&collision_paths, ", ",
2092 &collision_ent->source_files);
2093 output(o, 1, _("CONFLICT (implicit dir rename): Cannot map "
2094 "more than one path to %s; implicit directory "
2095 "renames tried to put these paths there: %s"),
2096 new_path, collision_paths.buf);
2097 clean = 0;
2098 }
2099
2100 /* Free memory we no longer need */
2101 strbuf_release(&collision_paths);
2102 if (!clean && new_path) {
2103 free(new_path);
2104 return NULL;
2105 }
2106
2107 return new_path;
2108 }
2109
2110 /*
2111 * There are a couple things we want to do at the directory level:
2112 * 1. Check for both sides renaming to the same thing, in order to avoid
2113 * implicit renaming of files that should be left in place. (See
2114 * testcase 6b in t6043 for details.)
2115 * 2. Prune directory renames if there are still files left in the
2116 * the original directory. These represent a partial directory rename,
2117 * i.e. a rename where only some of the files within the directory
2118 * were renamed elsewhere. (Technically, this could be done earlier
2119 * in get_directory_renames(), except that would prevent us from
2120 * doing the previous check and thus failing testcase 6b.)
2121 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
2122 * In the future, we could potentially record this info as well and
2123 * omit reporting rename/rename(1to2) conflicts for each path within
2124 * the affected directories, thus cleaning up the merge output.
2125 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
2126 * directory level, because merging directories is fine. If it
2127 * causes conflicts for files within those merged directories, then
2128 * that should be detected at the individual path level.
2129 */
2130 static void handle_directory_level_conflicts(struct merge_options *o,
2131 struct hashmap *dir_re_head,
2132 struct tree *head,
2133 struct hashmap *dir_re_merge,
2134 struct tree *merge)
2135 {
2136 struct hashmap_iter iter;
2137 struct dir_rename_entry *head_ent;
2138 struct dir_rename_entry *merge_ent;
2139
2140 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
2141 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
2142
2143 hashmap_iter_init(dir_re_head, &iter);
2144 while ((head_ent = hashmap_iter_next(&iter))) {
2145 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
2146 if (merge_ent &&
2147 !head_ent->non_unique_new_dir &&
2148 !merge_ent->non_unique_new_dir &&
2149 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
2150 /* 1. Renamed identically; remove it from both sides */
2151 string_list_append(&remove_from_head,
2152 head_ent->dir)->util = head_ent;
2153 strbuf_release(&head_ent->new_dir);
2154 string_list_append(&remove_from_merge,
2155 merge_ent->dir)->util = merge_ent;
2156 strbuf_release(&merge_ent->new_dir);
2157 } else if (tree_has_path(head, head_ent->dir)) {
2158 /* 2. This wasn't a directory rename after all */
2159 string_list_append(&remove_from_head,
2160 head_ent->dir)->util = head_ent;
2161 strbuf_release(&head_ent->new_dir);
2162 }
2163 }
2164
2165 remove_hashmap_entries(dir_re_head, &remove_from_head);
2166 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2167
2168 hashmap_iter_init(dir_re_merge, &iter);
2169 while ((merge_ent = hashmap_iter_next(&iter))) {
2170 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
2171 if (tree_has_path(merge, merge_ent->dir)) {
2172 /* 2. This wasn't a directory rename after all */
2173 string_list_append(&remove_from_merge,
2174 merge_ent->dir)->util = merge_ent;
2175 } else if (head_ent &&
2176 !head_ent->non_unique_new_dir &&
2177 !merge_ent->non_unique_new_dir) {
2178 /* 3. rename/rename(1to2) */
2179 /*
2180 * We can assume it's not rename/rename(1to1) because
2181 * that was case (1), already checked above. So we
2182 * know that head_ent->new_dir and merge_ent->new_dir
2183 * are different strings.
2184 */
2185 output(o, 1, _("CONFLICT (rename/rename): "
2186 "Rename directory %s->%s in %s. "
2187 "Rename directory %s->%s in %s"),
2188 head_ent->dir, head_ent->new_dir.buf, o->branch1,
2189 head_ent->dir, merge_ent->new_dir.buf, o->branch2);
2190 string_list_append(&remove_from_head,
2191 head_ent->dir)->util = head_ent;
2192 strbuf_release(&head_ent->new_dir);
2193 string_list_append(&remove_from_merge,
2194 merge_ent->dir)->util = merge_ent;
2195 strbuf_release(&merge_ent->new_dir);
2196 }
2197 }
2198
2199 remove_hashmap_entries(dir_re_head, &remove_from_head);
2200 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2201 }
2202
2203 static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
2204 struct tree *tree)
2205 {
2206 struct hashmap *dir_renames;
2207 struct hashmap_iter iter;
2208 struct dir_rename_entry *entry;
2209 int i;
2210
2211 /*
2212 * Typically, we think of a directory rename as all files from a
2213 * certain directory being moved to a target directory. However,
2214 * what if someone first moved two files from the original
2215 * directory in one commit, and then renamed the directory
2216 * somewhere else in a later commit? At merge time, we just know
2217 * that files from the original directory went to two different
2218 * places, and that the bulk of them ended up in the same place.
2219 * We want each directory rename to represent where the bulk of the
2220 * files from that directory end up; this function exists to find
2221 * where the bulk of the files went.
2222 *
2223 * The first loop below simply iterates through the list of file
2224 * renames, finding out how often each directory rename pair
2225 * possibility occurs.
2226 */
2227 dir_renames = xmalloc(sizeof(*dir_renames));
2228 dir_rename_init(dir_renames);
2229 for (i = 0; i < pairs->nr; ++i) {
2230 struct string_list_item *item;
2231 int *count;
2232 struct diff_filepair *pair = pairs->queue[i];
2233 char *old_dir, *new_dir;
2234
2235 /* File not part of directory rename if it wasn't renamed */
2236 if (pair->status != 'R')
2237 continue;
2238
2239 get_renamed_dir_portion(pair->one->path, pair->two->path,
2240 &old_dir, &new_dir);
2241 if (!old_dir)
2242 /* Directory didn't change at all; ignore this one. */
2243 continue;
2244
2245 entry = dir_rename_find_entry(dir_renames, old_dir);
2246 if (!entry) {
2247 entry = xmalloc(sizeof(*entry));
2248 dir_rename_entry_init(entry, old_dir);
2249 hashmap_put(dir_renames, entry);
2250 } else {
2251 free(old_dir);
2252 }
2253 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
2254 if (!item) {
2255 item = string_list_insert(&entry->possible_new_dirs,
2256 new_dir);
2257 item->util = xcalloc(1, sizeof(int));
2258 } else {
2259 free(new_dir);
2260 }
2261 count = item->util;
2262 *count += 1;
2263 }
2264
2265 /*
2266 * For each directory with files moved out of it, we find out which
2267 * target directory received the most files so we can declare it to
2268 * be the "winning" target location for the directory rename. This
2269 * winner gets recorded in new_dir. If there is no winner
2270 * (multiple target directories received the same number of files),
2271 * we set non_unique_new_dir. Once we've determined the winner (or
2272 * that there is no winner), we no longer need possible_new_dirs.
2273 */
2274 hashmap_iter_init(dir_renames, &iter);
2275 while ((entry = hashmap_iter_next(&iter))) {
2276 int max = 0;
2277 int bad_max = 0;
2278 char *best = NULL;
2279
2280 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
2281 int *count = entry->possible_new_dirs.items[i].util;
2282
2283 if (*count == max)
2284 bad_max = max;
2285 else if (*count > max) {
2286 max = *count;
2287 best = entry->possible_new_dirs.items[i].string;
2288 }
2289 }
2290 if (bad_max == max)
2291 entry->non_unique_new_dir = 1;
2292 else {
2293 assert(entry->new_dir.len == 0);
2294 strbuf_addstr(&entry->new_dir, best);
2295 }
2296 /*
2297 * The relevant directory sub-portion of the original full
2298 * filepaths were xstrndup'ed before inserting into
2299 * possible_new_dirs, and instead of manually iterating the
2300 * list and free'ing each, just lie and tell
2301 * possible_new_dirs that it did the strdup'ing so that it
2302 * will free them for us.
2303 */
2304 entry->possible_new_dirs.strdup_strings = 1;
2305 string_list_clear(&entry->possible_new_dirs, 1);
2306 }
2307
2308 return dir_renames;
2309 }
2310
2311 static struct dir_rename_entry *check_dir_renamed(const char *path,
2312 struct hashmap *dir_renames)
2313 {
2314 char *temp = xstrdup(path);
2315 char *end;
2316 struct dir_rename_entry *entry = NULL;
2317
2318 while ((end = strrchr(temp, '/'))) {
2319 *end = '\0';
2320 entry = dir_rename_find_entry(dir_renames, temp);
2321 if (entry)
2322 break;
2323 }
2324 free(temp);
2325 return entry;
2326 }
2327
2328 static void compute_collisions(struct hashmap *collisions,
2329 struct hashmap *dir_renames,
2330 struct diff_queue_struct *pairs)
2331 {
2332 int i;
2333
2334 /*
2335 * Multiple files can be mapped to the same path due to directory
2336 * renames done by the other side of history. Since that other
2337 * side of history could have merged multiple directories into one,
2338 * if our side of history added the same file basename to each of
2339 * those directories, then all N of them would get implicitly
2340 * renamed by the directory rename detection into the same path,
2341 * and we'd get an add/add/.../add conflict, and all those adds
2342 * from *this* side of history. This is not representable in the
2343 * index, and users aren't going to easily be able to make sense of
2344 * it. So we need to provide a good warning about what's
2345 * happening, and fall back to no-directory-rename detection
2346 * behavior for those paths.
2347 *
2348 * See testcases 9e and all of section 5 from t6043 for examples.
2349 */
2350 collision_init(collisions);
2351
2352 for (i = 0; i < pairs->nr; ++i) {
2353 struct dir_rename_entry *dir_rename_ent;
2354 struct collision_entry *collision_ent;
2355 char *new_path;
2356 struct diff_filepair *pair = pairs->queue[i];
2357
2358 if (pair->status != 'A' && pair->status != 'R')
2359 continue;
2360 dir_rename_ent = check_dir_renamed(pair->two->path,
2361 dir_renames);
2362 if (!dir_rename_ent)
2363 continue;
2364
2365 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
2366 if (!new_path)
2367 /*
2368 * dir_rename_ent->non_unique_new_path is true, which
2369 * means there is no directory rename for us to use,
2370 * which means it won't cause us any additional
2371 * collisions.
2372 */
2373 continue;
2374 collision_ent = collision_find_entry(collisions, new_path);
2375 if (!collision_ent) {
2376 collision_ent = xcalloc(1,
2377 sizeof(struct collision_entry));
2378 hashmap_entry_init(collision_ent, strhash(new_path));
2379 hashmap_put(collisions, collision_ent);
2380 collision_ent->target_file = new_path;
2381 } else {
2382 free(new_path);
2383 }
2384 string_list_insert(&collision_ent->source_files,
2385 pair->two->path);
2386 }
2387 }
2388
2389 static char *check_for_directory_rename(struct merge_options *o,
2390 const char *path,
2391 struct tree *tree,
2392 struct hashmap *dir_renames,
2393 struct hashmap *dir_rename_exclusions,
2394 struct hashmap *collisions,
2395 int *clean_merge)
2396 {
2397 char *new_path = NULL;
2398 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
2399 struct dir_rename_entry *oentry = NULL;
2400
2401 if (!entry)
2402 return new_path;
2403
2404 /*
2405 * This next part is a little weird. We do not want to do an
2406 * implicit rename into a directory we renamed on our side, because
2407 * that will result in a spurious rename/rename(1to2) conflict. An
2408 * example:
2409 * Base commit: dumbdir/afile, otherdir/bfile
2410 * Side 1: smrtdir/afile, otherdir/bfile
2411 * Side 2: dumbdir/afile, dumbdir/bfile
2412 * Here, while working on Side 1, we could notice that otherdir was
2413 * renamed/merged to dumbdir, and change the diff_filepair for
2414 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
2415 * 2 will notice the rename from dumbdir to smrtdir, and do the
2416 * transitive rename to move it from dumbdir/bfile to
2417 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
2418 * smrtdir, a rename/rename(1to2) conflict. We really just want
2419 * the file to end up in smrtdir. And the way to achieve that is
2420 * to not let Side1 do the rename to dumbdir, since we know that is
2421 * the source of one of our directory renames.
2422 *
2423 * That's why oentry and dir_rename_exclusions is here.
2424 *
2425 * As it turns out, this also prevents N-way transient rename
2426 * confusion; See testcases 9c and 9d of t6043.
2427 */
2428 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
2429 if (oentry) {
2430 output(o, 1, _("WARNING: Avoiding applying %s -> %s rename "
2431 "to %s, because %s itself was renamed."),
2432 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
2433 } else {
2434 new_path = handle_path_level_conflicts(o, path, entry,
2435 collisions, tree);
2436 *clean_merge &= (new_path != NULL);
2437 }
2438
2439 return new_path;
2440 }
2441
2442 static void apply_directory_rename_modifications(struct merge_options *o,
2443 struct diff_filepair *pair,
2444 char *new_path,
2445 struct rename *re,
2446 struct tree *tree,
2447 struct tree *o_tree,
2448 struct tree *a_tree,
2449 struct tree *b_tree,
2450 struct string_list *entries,
2451 int *clean)
2452 {
2453 struct string_list_item *item;
2454 int stage = (tree == a_tree ? 2 : 3);
2455 int update_wd;
2456
2457 /*
2458 * In all cases where we can do directory rename detection,
2459 * unpack_trees() will have read pair->two->path into the
2460 * index and the working copy. We need to remove it so that
2461 * we can instead place it at new_path. It is guaranteed to
2462 * not be untracked (unpack_trees() would have errored out
2463 * saying the file would have been overwritten), but it might
2464 * be dirty, though.
2465 */
2466 update_wd = !was_dirty(o, pair->two->path);
2467 if (!update_wd)
2468 output(o, 1, _("Refusing to lose dirty file at %s"),
2469 pair->two->path);
2470 remove_file(o, 1, pair->two->path, !update_wd);
2471
2472 /* Find or create a new re->dst_entry */
2473 item = string_list_lookup(entries, new_path);
2474 if (item) {
2475 /*
2476 * Since we're renaming on this side of history, and it's
2477 * due to a directory rename on the other side of history
2478 * (which we only allow when the directory in question no
2479 * longer exists on the other side of history), the
2480 * original entry for re->dst_entry is no longer
2481 * necessary...
2482 */
2483 re->dst_entry->processed = 1;
2484
2485 /*
2486 * ...because we'll be using this new one.
2487 */
2488 re->dst_entry = item->util;
2489 } else {
2490 /*
2491 * re->dst_entry is for the before-dir-rename path, and we
2492 * need it to hold information for the after-dir-rename
2493 * path. Before creating a new entry, we need to mark the
2494 * old one as unnecessary (...unless it is shared by
2495 * src_entry, i.e. this didn't use to be a rename, in which
2496 * case we can just allow the normal processing to happen
2497 * for it).
2498 */
2499 if (pair->status == 'R')
2500 re->dst_entry->processed = 1;
2501
2502 re->dst_entry = insert_stage_data(new_path,
2503 o_tree, a_tree, b_tree,
2504 entries);
2505 item = string_list_insert(entries, new_path);
2506 item->util = re->dst_entry;
2507 }
2508
2509 /*
2510 * Update the stage_data with the information about the path we are
2511 * moving into place. That slot will be empty and available for us
2512 * to write to because of the collision checks in
2513 * handle_path_level_conflicts(). In other words,
2514 * re->dst_entry->stages[stage].oid will be the null_oid, so it's
2515 * open for us to write to.
2516 *
2517 * It may be tempting to actually update the index at this point as
2518 * well, using update_stages_for_stage_data(), but as per the big
2519 * "NOTE" in update_stages(), doing so will modify the current
2520 * in-memory index which will break calls to would_lose_untracked()
2521 * that we need to make. Instead, we need to just make sure that
2522 * the various handle_rename_*() functions update the index
2523 * explicitly rather than relying on unpack_trees() to have done it.
2524 */
2525 get_tree_entry(&tree->object.oid,
2526 pair->two->path,
2527 &re->dst_entry->stages[stage].oid,
2528 &re->dst_entry->stages[stage].mode);
2529
2530 /* Update pair status */
2531 if (pair->status == 'A') {
2532 /*
2533 * Recording rename information for this add makes it look
2534 * like a rename/delete conflict. Make sure we can
2535 * correctly handle this as an add that was moved to a new
2536 * directory instead of reporting a rename/delete conflict.
2537 */
2538 re->add_turned_into_rename = 1;
2539 }
2540 /*
2541 * We don't actually look at pair->status again, but it seems
2542 * pedagogically correct to adjust it.
2543 */
2544 pair->status = 'R';
2545
2546 /*
2547 * Finally, record the new location.
2548 */
2549 pair->two->path = new_path;
2550 }
2551
2552 /*
2553 * Get information of all renames which occurred in 'pairs', making use of
2554 * any implicit directory renames inferred from the other side of history.
2555 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
2556 * to be able to associate the correct cache entries with the rename
2557 * information; tree is always equal to either a_tree or b_tree.
2558 */
2559 static struct string_list *get_renames(struct merge_options *o,
2560 struct diff_queue_struct *pairs,
2561 struct hashmap *dir_renames,
2562 struct hashmap *dir_rename_exclusions,
2563 struct tree *tree,
2564 struct tree *o_tree,
2565 struct tree *a_tree,
2566 struct tree *b_tree,
2567 struct string_list *entries,
2568 int *clean_merge)
2569 {
2570 int i;
2571 struct hashmap collisions;
2572 struct hashmap_iter iter;
2573 struct collision_entry *e;
2574 struct string_list *renames;
2575
2576 compute_collisions(&collisions, dir_renames, pairs);
2577 renames = xcalloc(1, sizeof(struct string_list));
2578
2579 for (i = 0; i < pairs->nr; ++i) {
2580 struct string_list_item *item;
2581 struct rename *re;
2582 struct diff_filepair *pair = pairs->queue[i];
2583 char *new_path; /* non-NULL only with directory renames */
2584
2585 if (pair->status != 'A' && pair->status != 'R') {
2586 diff_free_filepair(pair);
2587 continue;
2588 }
2589 new_path = check_for_directory_rename(o, pair->two->path, tree,
2590 dir_renames,
2591 dir_rename_exclusions,
2592 &collisions,
2593 clean_merge);
2594 if (pair->status != 'R' && !new_path) {
2595 diff_free_filepair(pair);
2596 continue;
2597 }
2598
2599 re = xmalloc(sizeof(*re));
2600 re->processed = 0;
2601 re->add_turned_into_rename = 0;
2602 re->pair = pair;
2603 item = string_list_lookup(entries, re->pair->one->path);
2604 if (!item)
2605 re->src_entry = insert_stage_data(re->pair->one->path,
2606 o_tree, a_tree, b_tree, entries);
2607 else
2608 re->src_entry = item->util;
2609
2610 item = string_list_lookup(entries, re->pair->two->path);
2611 if (!item)
2612 re->dst_entry = insert_stage_data(re->pair->two->path,
2613 o_tree, a_tree, b_tree, entries);
2614 else
2615 re->dst_entry = item->util;
2616 item = string_list_insert(renames, pair->one->path);
2617 item->util = re;
2618 if (new_path)
2619 apply_directory_rename_modifications(o, pair, new_path,
2620 re, tree, o_tree,
2621 a_tree, b_tree,
2622 entries,
2623 clean_merge);
2624 }
2625
2626 hashmap_iter_init(&collisions, &iter);
2627 while ((e = hashmap_iter_next(&iter))) {
2628 free(e->target_file);
2629 string_list_clear(&e->source_files, 0);
2630 }
2631 hashmap_free(&collisions, 1);
2632 return renames;
2633 }
2634
2635 static int process_renames(struct merge_options *o,
2636 struct string_list *a_renames,
2637 struct string_list *b_renames)
2638 {
2639 int clean_merge = 1, i, j;
2640 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2641 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2642 const struct rename *sre;
2643
2644 for (i = 0; i < a_renames->nr; i++) {
2645 sre = a_renames->items[i].util;
2646 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2647 = (void *)sre;
2648 }
2649 for (i = 0; i < b_renames->nr; i++) {
2650 sre = b_renames->items[i].util;
2651 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2652 = (void *)sre;
2653 }
2654
2655 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2656 struct string_list *renames1, *renames2Dst;
2657 struct rename *ren1 = NULL, *ren2 = NULL;
2658 const char *branch1, *branch2;
2659 const char *ren1_src, *ren1_dst;
2660 struct string_list_item *lookup;
2661
2662 if (i >= a_renames->nr) {
2663 ren2 = b_renames->items[j++].util;
2664 } else if (j >= b_renames->nr) {
2665 ren1 = a_renames->items[i++].util;
2666 } else {
2667 int compare = strcmp(a_renames->items[i].string,
2668 b_renames->items[j].string);
2669 if (compare <= 0)
2670 ren1 = a_renames->items[i++].util;
2671 if (compare >= 0)
2672 ren2 = b_renames->items[j++].util;
2673 }
2674
2675 /* TODO: refactor, so that 1/2 are not needed */
2676 if (ren1) {
2677 renames1 = a_renames;
2678 renames2Dst = &b_by_dst;
2679 branch1 = o->branch1;
2680 branch2 = o->branch2;
2681 } else {
2682 renames1 = b_renames;
2683 renames2Dst = &a_by_dst;
2684 branch1 = o->branch2;
2685 branch2 = o->branch1;
2686 SWAP(ren2, ren1);
2687 }
2688
2689 if (ren1->processed)
2690 continue;
2691 ren1->processed = 1;
2692 ren1->dst_entry->processed = 1;
2693 /* BUG: We should only mark src_entry as processed if we
2694 * are not dealing with a rename + add-source case.
2695 */
2696 ren1->src_entry->processed = 1;
2697
2698 ren1_src = ren1->pair->one->path;
2699 ren1_dst = ren1->pair->two->path;
2700
2701 if (ren2) {
2702 /* One file renamed on both sides */
2703 const char *ren2_src = ren2->pair->one->path;
2704 const char *ren2_dst = ren2->pair->two->path;
2705 enum rename_type rename_type;
2706 if (strcmp(ren1_src, ren2_src) != 0)
2707 BUG("ren1_src != ren2_src");
2708 ren2->dst_entry->processed = 1;
2709 ren2->processed = 1;
2710 if (strcmp(ren1_dst, ren2_dst) != 0) {
2711 rename_type = RENAME_ONE_FILE_TO_TWO;
2712 clean_merge = 0;
2713 } else {
2714 rename_type = RENAME_ONE_FILE_TO_ONE;
2715 /* BUG: We should only remove ren1_src in
2716 * the base stage (think of rename +
2717 * add-source cases).
2718 */
2719 remove_file(o, 1, ren1_src, 1);
2720 update_entry(ren1->dst_entry,
2721 ren1->pair->one,
2722 ren1->pair->two,
2723 ren2->pair->two);
2724 }
2725 setup_rename_conflict_info(rename_type,
2726 ren1->pair,
2727 ren2->pair,
2728 branch1,
2729 branch2,
2730 ren1->dst_entry,
2731 ren2->dst_entry,
2732 o,
2733 NULL,
2734 NULL);
2735 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2736 /* Two different files renamed to the same thing */
2737 char *ren2_dst;
2738 ren2 = lookup->util;
2739 ren2_dst = ren2->pair->two->path;
2740 if (strcmp(ren1_dst, ren2_dst) != 0)
2741 BUG("ren1_dst != ren2_dst");
2742
2743 clean_merge = 0;
2744 ren2->processed = 1;
2745 /*
2746 * BUG: We should only mark src_entry as processed
2747 * if we are not dealing with a rename + add-source
2748 * case.
2749 */
2750 ren2->src_entry->processed = 1;
2751
2752 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2753 ren1->pair,
2754 ren2->pair,
2755 branch1,
2756 branch2,
2757 ren1->dst_entry,
2758 ren2->dst_entry,
2759 o,
2760 ren1->src_entry,
2761 ren2->src_entry);
2762
2763 } else {
2764 /* Renamed in 1, maybe changed in 2 */
2765 /* we only use sha1 and mode of these */
2766 struct diff_filespec src_other, dst_other;
2767 int try_merge;
2768
2769 /*
2770 * unpack_trees loads entries from common-commit
2771 * into stage 1, from head-commit into stage 2, and
2772 * from merge-commit into stage 3. We keep track
2773 * of which side corresponds to the rename.
2774 */
2775 int renamed_stage = a_renames == renames1 ? 2 : 3;
2776 int other_stage = a_renames == renames1 ? 3 : 2;
2777
2778 /* BUG: We should only remove ren1_src in the base
2779 * stage and in other_stage (think of rename +
2780 * add-source case).
2781 */
2782 remove_file(o, 1, ren1_src,
2783 renamed_stage == 2 || !was_tracked(o, ren1_src));
2784
2785 oidcpy(&src_other.oid,
2786 &ren1->src_entry->stages[other_stage].oid);
2787 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2788 oidcpy(&dst_other.oid,
2789 &ren1->dst_entry->stages[other_stage].oid);
2790 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2791 try_merge = 0;
2792
2793 if (oid_eq(&src_other.oid, &null_oid) &&
2794 ren1->add_turned_into_rename) {
2795 setup_rename_conflict_info(RENAME_VIA_DIR,
2796 ren1->pair,
2797 NULL,
2798 branch1,
2799 branch2,
2800 ren1->dst_entry,
2801 NULL,
2802 o,
2803 NULL,
2804 NULL);
2805 } else if (oid_eq(&src_other.oid, &null_oid)) {
2806 setup_rename_conflict_info(RENAME_DELETE,
2807 ren1->pair,
2808 NULL,
2809 branch1,
2810 branch2,
2811 ren1->dst_entry,
2812 NULL,
2813 o,
2814 NULL,
2815 NULL);
2816 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2817 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2818 /*
2819 * Added file on the other side identical to
2820 * the file being renamed: clean merge.
2821 * Also, there is no need to overwrite the
2822 * file already in the working copy, so call
2823 * update_file_flags() instead of
2824 * update_file().
2825 */
2826 if (update_file_flags(o,
2827 &ren1->pair->two->oid,
2828 ren1->pair->two->mode,
2829 ren1_dst,
2830 1, /* update_cache */
2831 0 /* update_wd */))
2832 clean_merge = -1;
2833 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2834 /*
2835 * Probably not a clean merge, but it's
2836 * premature to set clean_merge to 0 here,
2837 * because if the rename merges cleanly and
2838 * the merge exactly matches the newly added
2839 * file, then the merge will be clean.
2840 */
2841 setup_rename_conflict_info(RENAME_ADD,
2842 ren1->pair,
2843 NULL,
2844 branch1,
2845 branch2,
2846 ren1->dst_entry,
2847 NULL,
2848 o,
2849 ren1->src_entry,
2850 NULL);
2851 } else
2852 try_merge = 1;
2853
2854 if (clean_merge < 0)
2855 goto cleanup_and_return;
2856 if (try_merge) {
2857 struct diff_filespec *one, *a, *b;
2858 src_other.path = (char *)ren1_src;
2859
2860 one = ren1->pair->one;
2861 if (a_renames == renames1) {
2862 a = ren1->pair->two;
2863 b = &src_other;
2864 } else {
2865 b = ren1->pair->two;
2866 a = &src_other;
2867 }
2868 update_entry(ren1->dst_entry, one, a, b);
2869 setup_rename_conflict_info(RENAME_NORMAL,
2870 ren1->pair,
2871 NULL,
2872 branch1,
2873 NULL,
2874 ren1->dst_entry,
2875 NULL,
2876 o,
2877 NULL,
2878 NULL);
2879 }
2880 }
2881 }
2882 cleanup_and_return:
2883 string_list_clear(&a_by_dst, 0);
2884 string_list_clear(&b_by_dst, 0);
2885
2886 return clean_merge;
2887 }
2888
2889 struct rename_info {
2890 struct string_list *head_renames;
2891 struct string_list *merge_renames;
2892 };
2893
2894 static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2895 struct hashmap *dir_renames)
2896 {
2897 struct hashmap_iter iter;
2898 struct dir_rename_entry *e;
2899
2900 hashmap_iter_init(dir_renames, &iter);
2901 while ((e = hashmap_iter_next(&iter))) {
2902 free(e->dir);
2903 strbuf_release(&e->new_dir);
2904 /* possible_new_dirs already cleared in get_directory_renames */
2905 }
2906 hashmap_free(dir_renames, 1);
2907 free(dir_renames);
2908
2909 free(pairs->queue);
2910 free(pairs);
2911 }
2912
2913 static int detect_and_process_renames(struct merge_options *o,
2914 struct tree *common,
2915 struct tree *head,
2916 struct tree *merge,
2917 struct string_list *entries,
2918 struct rename_info *ri)
2919 {
2920 struct diff_queue_struct *head_pairs, *merge_pairs;
2921 struct hashmap *dir_re_head, *dir_re_merge;
2922 int clean = 1;
2923
2924 ri->head_renames = NULL;
2925 ri->merge_renames = NULL;
2926
2927 if (!merge_detect_rename(o))
2928 return 1;
2929
2930 head_pairs = get_diffpairs(o, common, head);
2931 merge_pairs = get_diffpairs(o, common, merge);
2932
2933 if (o->detect_directory_renames) {
2934 dir_re_head = get_directory_renames(head_pairs, head);
2935 dir_re_merge = get_directory_renames(merge_pairs, merge);
2936
2937 handle_directory_level_conflicts(o,
2938 dir_re_head, head,
2939 dir_re_merge, merge);
2940 } else {
2941 dir_re_head = xmalloc(sizeof(*dir_re_head));
2942 dir_re_merge = xmalloc(sizeof(*dir_re_merge));
2943 dir_rename_init(dir_re_head);
2944 dir_rename_init(dir_re_merge);
2945 }
2946
2947 ri->head_renames = get_renames(o, head_pairs,
2948 dir_re_merge, dir_re_head, head,
2949 common, head, merge, entries,
2950 &clean);
2951 if (clean < 0)
2952 goto cleanup;
2953 ri->merge_renames = get_renames(o, merge_pairs,
2954 dir_re_head, dir_re_merge, merge,
2955 common, head, merge, entries,
2956 &clean);
2957 if (clean < 0)
2958 goto cleanup;
2959 clean &= process_renames(o, ri->head_renames, ri->merge_renames);
2960
2961 cleanup:
2962 /*
2963 * Some cleanup is deferred until cleanup_renames() because the
2964 * data structures are still needed and referenced in
2965 * process_entry(). But there are a few things we can free now.
2966 */
2967 initial_cleanup_rename(head_pairs, dir_re_head);
2968 initial_cleanup_rename(merge_pairs, dir_re_merge);
2969
2970 return clean;
2971 }
2972
2973 static void final_cleanup_rename(struct string_list *rename)
2974 {
2975 const struct rename *re;
2976 int i;
2977
2978 if (rename == NULL)
2979 return;
2980
2981 for (i = 0; i < rename->nr; i++) {
2982 re = rename->items[i].util;
2983 diff_free_filepair(re->pair);
2984 }
2985 string_list_clear(rename, 1);
2986 free(rename);
2987 }
2988
2989 static void final_cleanup_renames(struct rename_info *re_info)
2990 {
2991 final_cleanup_rename(re_info->head_renames);
2992 final_cleanup_rename(re_info->merge_renames);
2993 }
2994
2995 static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
2996 {
2997 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
2998 }
2999
3000 static int read_oid_strbuf(struct merge_options *o,
3001 const struct object_id *oid,
3002 struct strbuf *dst)
3003 {
3004 void *buf;
3005 enum object_type type;
3006 unsigned long size;
3007 buf = read_object_file(oid, &type, &size);
3008 if (!buf)
3009 return err(o, _("cannot read object %s"), oid_to_hex(oid));
3010 if (type != OBJ_BLOB) {
3011 free(buf);
3012 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
3013 }
3014 strbuf_attach(dst, buf, size, size + 1);
3015 return 0;
3016 }
3017
3018 static int blob_unchanged(struct merge_options *opt,
3019 const struct object_id *o_oid,
3020 unsigned o_mode,
3021 const struct object_id *a_oid,
3022 unsigned a_mode,
3023 int renormalize, const char *path)
3024 {
3025 struct strbuf o = STRBUF_INIT;
3026 struct strbuf a = STRBUF_INIT;
3027 int ret = 0; /* assume changed for safety */
3028
3029 if (a_mode != o_mode)
3030 return 0;
3031 if (oid_eq(o_oid, a_oid))
3032 return 1;
3033 if (!renormalize)
3034 return 0;
3035
3036 assert(o_oid && a_oid);
3037 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
3038 goto error_return;
3039 /*
3040 * Note: binary | is used so that both renormalizations are
3041 * performed. Comparison can be skipped if both files are
3042 * unchanged since their sha1s have already been compared.
3043 */
3044 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
3045 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
3046 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
3047
3048 error_return:
3049 strbuf_release(&o);
3050 strbuf_release(&a);
3051 return ret;
3052 }
3053
3054 static int handle_modify_delete(struct merge_options *o,
3055 const char *path,
3056 struct object_id *o_oid, int o_mode,
3057 struct object_id *a_oid, int a_mode,
3058 struct object_id *b_oid, int b_mode)
3059 {
3060 const char *modify_branch, *delete_branch;
3061 struct object_id *changed_oid;
3062 int changed_mode;
3063
3064 if (a_oid) {
3065 modify_branch = o->branch1;
3066 delete_branch = o->branch2;
3067 changed_oid = a_oid;
3068 changed_mode = a_mode;
3069 } else {
3070 modify_branch = o->branch2;
3071 delete_branch = o->branch1;
3072 changed_oid = b_oid;
3073 changed_mode = b_mode;
3074 }
3075
3076 return handle_change_delete(o,
3077 path, NULL,
3078 o_oid, o_mode,
3079 changed_oid, changed_mode,
3080 modify_branch, delete_branch,
3081 _("modify"), _("modified"));
3082 }
3083
3084 static int handle_content_merge(struct merge_options *o,
3085 const char *path,
3086 int is_dirty,
3087 struct object_id *o_oid, int o_mode,
3088 struct object_id *a_oid, int a_mode,
3089 struct object_id *b_oid, int b_mode,
3090 struct rename_conflict_info *rename_conflict_info)
3091 {
3092 const char *reason = _("content");
3093 const char *path1 = NULL, *path2 = NULL;
3094 struct merge_file_info mfi;
3095 struct diff_filespec one, a, b;
3096 unsigned df_conflict_remains = 0;
3097
3098 if (!o_oid) {
3099 reason = _("add/add");
3100 o_oid = (struct object_id *)&null_oid;
3101 }
3102 one.path = a.path = b.path = (char *)path;
3103 oidcpy(&one.oid, o_oid);
3104 one.mode = o_mode;
3105 oidcpy(&a.oid, a_oid);
3106 a.mode = a_mode;
3107 oidcpy(&b.oid, b_oid);
3108 b.mode = b_mode;
3109
3110 if (rename_conflict_info) {
3111 struct diff_filepair *pair1 = rename_conflict_info->pair1;
3112
3113 path1 = (o->branch1 == rename_conflict_info->branch1) ?
3114 pair1->two->path : pair1->one->path;
3115 /* If rename_conflict_info->pair2 != NULL, we are in
3116 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
3117 * normal rename.
3118 */
3119 path2 = (rename_conflict_info->pair2 ||
3120 o->branch2 == rename_conflict_info->branch1) ?
3121 pair1->two->path : pair1->one->path;
3122 one.path = pair1->one->path;
3123 a.path = (char *)path1;
3124 b.path = (char *)path2;
3125
3126 if (dir_in_way(path, !o->call_depth,
3127 S_ISGITLINK(pair1->two->mode)))
3128 df_conflict_remains = 1;
3129 }
3130 if (merge_mode_and_contents(o, &one, &a, &b, path,
3131 o->branch1, o->branch2,
3132 o->call_depth * 2, &mfi))
3133 return -1;
3134
3135 /*
3136 * We can skip updating the working tree file iff:
3137 * a) The merge is clean
3138 * b) The merge matches what was in HEAD (content, mode, pathname)
3139 * c) The target path is usable (i.e. not involved in D/F conflict)
3140 */
3141 if (mfi.clean &&
3142 was_tracked_and_matches(o, path, &mfi.oid, mfi.mode) &&
3143 !df_conflict_remains) {
3144 int pos;
3145 struct cache_entry *ce;
3146
3147 output(o, 3, _("Skipped %s (merged same as existing)"), path);
3148 if (add_cacheinfo(o, mfi.mode, &mfi.oid, path,
3149 0, (!o->call_depth && !is_dirty), 0))
3150 return -1;
3151 /*
3152 * However, add_cacheinfo() will delete the old cache entry
3153 * and add a new one. We need to copy over any skip_worktree
3154 * flag to avoid making the file appear as if it were
3155 * deleted by the user.
3156 */
3157 pos = index_name_pos(&o->orig_index, path, strlen(path));
3158 ce = o->orig_index.cache[pos];
3159 if (ce_skip_worktree(ce)) {
3160 pos = index_name_pos(&the_index, path, strlen(path));
3161 ce = the_index.cache[pos];
3162 ce->ce_flags |= CE_SKIP_WORKTREE;
3163 }
3164 return mfi.clean;
3165 }
3166
3167 if (!mfi.clean) {
3168 if (S_ISGITLINK(mfi.mode))
3169 reason = _("submodule");
3170 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
3171 reason, path);
3172 if (rename_conflict_info && !df_conflict_remains)
3173 if (update_stages(o, path, &one, &a, &b))
3174 return -1;
3175 }
3176
3177 if (df_conflict_remains || is_dirty) {
3178 char *new_path;
3179 if (o->call_depth) {
3180 remove_file_from_cache(path);
3181 } else {
3182 if (!mfi.clean) {
3183 if (update_stages(o, path, &one, &a, &b))
3184 return -1;
3185 } else {
3186 int file_from_stage2 = was_tracked(o, path);
3187 struct diff_filespec merged;
3188 oidcpy(&merged.oid, &mfi.oid);
3189 merged.mode = mfi.mode;
3190
3191 if (update_stages(o, path, NULL,
3192 file_from_stage2 ? &merged : NULL,
3193 file_from_stage2 ? NULL : &merged))
3194 return -1;
3195 }
3196
3197 }
3198 new_path = unique_path(o, path, rename_conflict_info->branch1);
3199 if (is_dirty) {
3200 output(o, 1, _("Refusing to lose dirty file at %s"),
3201 path);
3202 }
3203 output(o, 1, _("Adding as %s instead"), new_path);
3204 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
3205 free(new_path);
3206 return -1;
3207 }
3208 free(new_path);
3209 mfi.clean = 0;
3210 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
3211 return -1;
3212 return !is_dirty && mfi.clean;
3213 }
3214
3215 static int handle_rename_normal(struct merge_options *o,
3216 const char *path,
3217 struct object_id *o_oid, unsigned int o_mode,
3218 struct object_id *a_oid, unsigned int a_mode,
3219 struct object_id *b_oid, unsigned int b_mode,
3220 struct rename_conflict_info *ci)
3221 {
3222 /* Merge the content and write it out */
3223 return handle_content_merge(o, path, was_dirty(o, path),
3224 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3225 ci);
3226 }
3227
3228 /* Per entry merge function */
3229 static int process_entry(struct merge_options *o,
3230 const char *path, struct stage_data *entry)
3231 {
3232 int clean_merge = 1;
3233 int normalize = o->renormalize;
3234 unsigned o_mode = entry->stages[1].mode;
3235 unsigned a_mode = entry->stages[2].mode;
3236 unsigned b_mode = entry->stages[3].mode;
3237 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
3238 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
3239 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
3240
3241 entry->processed = 1;
3242 if (entry->rename_conflict_info) {
3243 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
3244 switch (conflict_info->rename_type) {
3245 case RENAME_NORMAL:
3246 case RENAME_ONE_FILE_TO_ONE:
3247 clean_merge = handle_rename_normal(o,
3248 path,
3249 o_oid, o_mode,
3250 a_oid, a_mode,
3251 b_oid, b_mode,
3252 conflict_info);
3253 break;
3254 case RENAME_VIA_DIR:
3255 clean_merge = 1;
3256 if (handle_rename_via_dir(o,
3257 conflict_info->pair1,
3258 conflict_info->branch1,
3259 conflict_info->branch2))
3260 clean_merge = -1;
3261 break;
3262 case RENAME_ADD:
3263 /*
3264 * Probably unclean merge, but if the renamed file
3265 * merges cleanly and the result can then be
3266 * two-way merged cleanly with the added file, I
3267 * guess it's a clean merge?
3268 */
3269 clean_merge = handle_rename_add(o, conflict_info);
3270 break;
3271 case RENAME_DELETE:
3272 clean_merge = 0;
3273 if (handle_rename_delete(o,
3274 conflict_info->pair1,
3275 conflict_info->branch1,
3276 conflict_info->branch2))
3277 clean_merge = -1;
3278 break;
3279 case RENAME_ONE_FILE_TO_TWO:
3280 clean_merge = 0;
3281 if (handle_rename_rename_1to2(o, conflict_info))
3282 clean_merge = -1;
3283 break;
3284 case RENAME_TWO_FILES_TO_ONE:
3285 /*
3286 * Probably unclean merge, but if the two renamed
3287 * files merge cleanly and the two resulting files
3288 * can then be two-way merged cleanly, I guess it's
3289 * a clean merge?
3290 */
3291 clean_merge = handle_rename_rename_2to1(o,
3292 conflict_info);
3293 break;
3294 default:
3295 entry->processed = 0;
3296 break;
3297 }
3298 } else if (o_oid && (!a_oid || !b_oid)) {
3299 /* Case A: Deleted in one */
3300 if ((!a_oid && !b_oid) ||
3301 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
3302 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
3303 /* Deleted in both or deleted in one and
3304 * unchanged in the other */
3305 if (a_oid)
3306 output(o, 2, _("Removing %s"), path);
3307 /* do not touch working file if it did not exist */
3308 remove_file(o, 1, path, !a_oid);
3309 } else {
3310 /* Modify/delete; deleted side may have put a directory in the way */
3311 clean_merge = 0;
3312 if (handle_modify_delete(o, path, o_oid, o_mode,
3313 a_oid, a_mode, b_oid, b_mode))
3314 clean_merge = -1;
3315 }
3316 } else if ((!o_oid && a_oid && !b_oid) ||
3317 (!o_oid && !a_oid && b_oid)) {
3318 /* Case B: Added in one. */
3319 /* [nothing|directory] -> ([nothing|directory], file) */
3320
3321 const char *add_branch;
3322 const char *other_branch;
3323 unsigned mode;
3324 const struct object_id *oid;
3325 const char *conf;
3326
3327 if (a_oid) {
3328 add_branch = o->branch1;
3329 other_branch = o->branch2;
3330 mode = a_mode;
3331 oid = a_oid;
3332 conf = _("file/directory");
3333 } else {
3334 add_branch = o->branch2;
3335 other_branch = o->branch1;
3336 mode = b_mode;
3337 oid = b_oid;
3338 conf = _("directory/file");
3339 }
3340 if (dir_in_way(path,
3341 !o->call_depth && !S_ISGITLINK(a_mode),
3342 0)) {
3343 char *new_path = unique_path(o, path, add_branch);
3344 clean_merge = 0;
3345 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
3346 "Adding %s as %s"),
3347 conf, path, other_branch, path, new_path);
3348 if (update_file(o, 0, oid, mode, new_path))
3349 clean_merge = -1;
3350 else if (o->call_depth)
3351 remove_file_from_cache(path);
3352 free(new_path);
3353 } else {
3354 output(o, 2, _("Adding %s"), path);
3355 /* do not overwrite file if already present */
3356 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
3357 clean_merge = -1;
3358 }
3359 } else if (a_oid && b_oid) {
3360 if (!o_oid) {
3361 /* Case C: Added in both (check for same permissions) */
3362 output(o, 1,
3363 _("CONFLICT (add/add): Merge conflict in %s"),
3364 path);
3365 clean_merge = handle_file_collision(o,
3366 path, NULL, NULL,
3367 o->branch1,
3368 o->branch2,
3369 a_oid, a_mode,
3370 b_oid, b_mode);
3371 } else {
3372 /* case D: Modified in both, but differently. */
3373 int is_dirty = 0; /* unpack_trees would have bailed if dirty */
3374 clean_merge = handle_content_merge(o, path,
3375 is_dirty,
3376 o_oid, o_mode,
3377 a_oid, a_mode,
3378 b_oid, b_mode,
3379 NULL);
3380 }
3381 } else if (!o_oid && !a_oid && !b_oid) {
3382 /*
3383 * this entry was deleted altogether. a_mode == 0 means
3384 * we had that path and want to actively remove it.
3385 */
3386 remove_file(o, 1, path, !a_mode);
3387 } else
3388 BUG("fatal merge failure, shouldn't happen.");
3389
3390 return clean_merge;
3391 }
3392
3393 int merge_trees(struct merge_options *o,
3394 struct tree *head,
3395 struct tree *merge,
3396 struct tree *common,
3397 struct tree **result)
3398 {
3399 int code, clean;
3400 struct strbuf sb = STRBUF_INIT;
3401
3402 if (!o->call_depth && index_has_changes(&the_index, head, &sb)) {
3403 err(o, _("Your local changes to the following files would be overwritten by merge:\n %s"),
3404 sb.buf);
3405 return -1;
3406 }
3407
3408 if (o->subtree_shift) {
3409 merge = shift_tree_object(head, merge, o->subtree_shift);
3410 common = shift_tree_object(head, common, o->subtree_shift);
3411 }
3412
3413 if (oid_eq(&common->object.oid, &merge->object.oid)) {
3414 output(o, 0, _("Already up to date!"));
3415 *result = head;
3416 return 1;
3417 }
3418
3419 code = unpack_trees_start(o, common, head, merge);
3420
3421 if (code != 0) {
3422 if (show(o, 4) || o->call_depth)
3423 err(o, _("merging of trees %s and %s failed"),
3424 oid_to_hex(&head->object.oid),
3425 oid_to_hex(&merge->object.oid));
3426 unpack_trees_finish(o);
3427 return -1;
3428 }
3429
3430 if (unmerged_cache()) {
3431 struct string_list *entries;
3432 struct rename_info re_info;
3433 int i;
3434 /*
3435 * Only need the hashmap while processing entries, so
3436 * initialize it here and free it when we are done running
3437 * through the entries. Keeping it in the merge_options as
3438 * opposed to decaring a local hashmap is for convenience
3439 * so that we don't have to pass it to around.
3440 */
3441 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
3442 get_files_dirs(o, head);
3443 get_files_dirs(o, merge);
3444
3445 entries = get_unmerged();
3446 clean = detect_and_process_renames(o, common, head, merge,
3447 entries, &re_info);
3448 record_df_conflict_files(o, entries);
3449 if (clean < 0)
3450 goto cleanup;
3451 for (i = entries->nr-1; 0 <= i; i--) {
3452 const char *path = entries->items[i].string;
3453 struct stage_data *e = entries->items[i].util;
3454 if (!e->processed) {
3455 int ret = process_entry(o, path, e);
3456 if (!ret)
3457 clean = 0;
3458 else if (ret < 0) {
3459 clean = ret;
3460 goto cleanup;
3461 }
3462 }
3463 }
3464 for (i = 0; i < entries->nr; i++) {
3465 struct stage_data *e = entries->items[i].util;
3466 if (!e->processed)
3467 BUG("unprocessed path??? %s",
3468 entries->items[i].string);
3469 }
3470
3471 cleanup:
3472 final_cleanup_renames(&re_info);
3473
3474 string_list_clear(entries, 1);
3475 free(entries);
3476
3477 hashmap_free(&o->current_file_dir_set, 1);
3478
3479 if (clean < 0) {
3480 unpack_trees_finish(o);
3481 return clean;
3482 }
3483 }
3484 else
3485 clean = 1;
3486
3487 unpack_trees_finish(o);
3488
3489 if (o->call_depth && !(*result = write_tree_from_memory(o)))
3490 return -1;
3491
3492 return clean;
3493 }
3494
3495 static struct commit_list *reverse_commit_list(struct commit_list *list)
3496 {
3497 struct commit_list *next = NULL, *current, *backup;
3498 for (current = list; current; current = backup) {
3499 backup = current->next;
3500 current->next = next;
3501 next = current;
3502 }
3503 return next;
3504 }
3505
3506 /*
3507 * Merge the commits h1 and h2, return the resulting virtual
3508 * commit object and a flag indicating the cleanness of the merge.
3509 */
3510 int merge_recursive(struct merge_options *o,
3511 struct commit *h1,
3512 struct commit *h2,
3513 struct commit_list *ca,
3514 struct commit **result)
3515 {
3516 struct commit_list *iter;
3517 struct commit *merged_common_ancestors;
3518 struct tree *mrtree;
3519 int clean;
3520
3521 if (show(o, 4)) {
3522 output(o, 4, _("Merging:"));
3523 output_commit_title(o, h1);
3524 output_commit_title(o, h2);
3525 }
3526
3527 if (!ca) {
3528 ca = get_merge_bases(h1, h2);
3529 ca = reverse_commit_list(ca);
3530 }
3531
3532 if (show(o, 5)) {
3533 unsigned cnt = commit_list_count(ca);
3534
3535 output(o, 5, Q_("found %u common ancestor:",
3536 "found %u common ancestors:", cnt), cnt);
3537 for (iter = ca; iter; iter = iter->next)
3538 output_commit_title(o, iter->item);
3539 }
3540
3541 merged_common_ancestors = pop_commit(&ca);
3542 if (merged_common_ancestors == NULL) {
3543 /* if there is no common ancestor, use an empty tree */
3544 struct tree *tree;
3545
3546 tree = lookup_tree(the_repository, the_repository->hash_algo->empty_tree);
3547 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
3548 }
3549
3550 for (iter = ca; iter; iter = iter->next) {
3551 const char *saved_b1, *saved_b2;
3552 o->call_depth++;
3553 /*
3554 * When the merge fails, the result contains files
3555 * with conflict markers. The cleanness flag is
3556 * ignored (unless indicating an error), it was never
3557 * actually used, as result of merge_trees has always
3558 * overwritten it: the committed "conflicts" were
3559 * already resolved.
3560 */
3561 discard_cache();
3562 saved_b1 = o->branch1;
3563 saved_b2 = o->branch2;
3564 o->branch1 = "Temporary merge branch 1";
3565 o->branch2 = "Temporary merge branch 2";
3566 if (merge_recursive(o, merged_common_ancestors, iter->item,
3567 NULL, &merged_common_ancestors) < 0)
3568 return -1;
3569 o->branch1 = saved_b1;
3570 o->branch2 = saved_b2;
3571 o->call_depth--;
3572
3573 if (!merged_common_ancestors)
3574 return err(o, _("merge returned no commit"));
3575 }
3576
3577 discard_cache();
3578 if (!o->call_depth)
3579 repo_read_index(the_repository);
3580
3581 o->ancestor = "merged common ancestors";
3582 clean = merge_trees(o, get_commit_tree(h1), get_commit_tree(h2),
3583 get_commit_tree(merged_common_ancestors),
3584 &mrtree);
3585 if (clean < 0) {
3586 flush_output(o);
3587 return clean;
3588 }
3589
3590 if (o->call_depth) {
3591 *result = make_virtual_commit(mrtree, "merged tree");
3592 commit_list_insert(h1, &(*result)->parents);
3593 commit_list_insert(h2, &(*result)->parents->next);
3594 }
3595 flush_output(o);
3596 if (!o->call_depth && o->buffer_output < 2)
3597 strbuf_release(&o->obuf);
3598 if (show(o, 2))
3599 diff_warn_rename_limit("merge.renamelimit",
3600 o->needed_rename_limit, 0);
3601 return clean;
3602 }
3603
3604 static struct commit *get_ref(const struct object_id *oid, const char *name)
3605 {
3606 struct object *object;
3607
3608 object = deref_tag(the_repository, parse_object(the_repository, oid),
3609 name,
3610 strlen(name));
3611 if (!object)
3612 return NULL;
3613 if (object->type == OBJ_TREE)
3614 return make_virtual_commit((struct tree*)object, name);
3615 if (object->type != OBJ_COMMIT)
3616 return NULL;
3617 if (parse_commit((struct commit *)object))
3618 return NULL;
3619 return (struct commit *)object;
3620 }
3621
3622 int merge_recursive_generic(struct merge_options *o,
3623 const struct object_id *head,
3624 const struct object_id *merge,
3625 int num_base_list,
3626 const struct object_id **base_list,
3627 struct commit **result)
3628 {
3629 int clean;