tree: add repository argument to lookup_tree
[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
31 struct path_hashmap_entry {
32 struct hashmap_entry e;
33 char path[FLEX_ARRAY];
34 };
35
36 static int path_hashmap_cmp(const void *cmp_data,
37 const void *entry,
38 const void *entry_or_key,
39 const void *keydata)
40 {
41 const struct path_hashmap_entry *a = entry;
42 const struct path_hashmap_entry *b = entry_or_key;
43 const char *key = keydata;
44
45 if (ignore_case)
46 return strcasecmp(a->path, key ? key : b->path);
47 else
48 return strcmp(a->path, key ? key : b->path);
49 }
50
51 static unsigned int path_hash(const char *path)
52 {
53 return ignore_case ? strihash(path) : strhash(path);
54 }
55
56 static struct dir_rename_entry *dir_rename_find_entry(struct hashmap *hashmap,
57 char *dir)
58 {
59 struct dir_rename_entry key;
60
61 if (dir == NULL)
62 return NULL;
63 hashmap_entry_init(&key, strhash(dir));
64 key.dir = dir;
65 return hashmap_get(hashmap, &key, NULL);
66 }
67
68 static int dir_rename_cmp(const void *unused_cmp_data,
69 const void *entry,
70 const void *entry_or_key,
71 const void *unused_keydata)
72 {
73 const struct dir_rename_entry *e1 = entry;
74 const struct dir_rename_entry *e2 = entry_or_key;
75
76 return strcmp(e1->dir, e2->dir);
77 }
78
79 static void dir_rename_init(struct hashmap *map)
80 {
81 hashmap_init(map, dir_rename_cmp, NULL, 0);
82 }
83
84 static void dir_rename_entry_init(struct dir_rename_entry *entry,
85 char *directory)
86 {
87 hashmap_entry_init(entry, strhash(directory));
88 entry->dir = directory;
89 entry->non_unique_new_dir = 0;
90 strbuf_init(&entry->new_dir, 0);
91 string_list_init(&entry->possible_new_dirs, 0);
92 }
93
94 static struct collision_entry *collision_find_entry(struct hashmap *hashmap,
95 char *target_file)
96 {
97 struct collision_entry key;
98
99 hashmap_entry_init(&key, strhash(target_file));
100 key.target_file = target_file;
101 return hashmap_get(hashmap, &key, NULL);
102 }
103
104 static int collision_cmp(void *unused_cmp_data,
105 const struct collision_entry *e1,
106 const struct collision_entry *e2,
107 const void *unused_keydata)
108 {
109 return strcmp(e1->target_file, e2->target_file);
110 }
111
112 static void collision_init(struct hashmap *map)
113 {
114 hashmap_init(map, (hashmap_cmp_fn) collision_cmp, NULL, 0);
115 }
116
117 static void flush_output(struct merge_options *o)
118 {
119 if (o->buffer_output < 2 && o->obuf.len) {
120 fputs(o->obuf.buf, stdout);
121 strbuf_reset(&o->obuf);
122 }
123 }
124
125 static int err(struct merge_options *o, const char *err, ...)
126 {
127 va_list params;
128
129 if (o->buffer_output < 2)
130 flush_output(o);
131 else {
132 strbuf_complete(&o->obuf, '\n');
133 strbuf_addstr(&o->obuf, "error: ");
134 }
135 va_start(params, err);
136 strbuf_vaddf(&o->obuf, err, params);
137 va_end(params);
138 if (o->buffer_output > 1)
139 strbuf_addch(&o->obuf, '\n');
140 else {
141 error("%s", o->obuf.buf);
142 strbuf_reset(&o->obuf);
143 }
144
145 return -1;
146 }
147
148 static struct tree *shift_tree_object(struct tree *one, struct tree *two,
149 const char *subtree_shift)
150 {
151 struct object_id shifted;
152
153 if (!*subtree_shift) {
154 shift_tree(&one->object.oid, &two->object.oid, &shifted, 0);
155 } else {
156 shift_tree_by(&one->object.oid, &two->object.oid, &shifted,
157 subtree_shift);
158 }
159 if (!oidcmp(&two->object.oid, &shifted))
160 return two;
161 return lookup_tree(the_repository, &shifted);
162 }
163
164 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
165 {
166 struct commit *commit = alloc_commit_node(the_repository);
167
168 set_merge_remote_desc(commit, comment, (struct object *)commit);
169 commit->maybe_tree = tree;
170 commit->object.parsed = 1;
171 return commit;
172 }
173
174 /*
175 * Since we use get_tree_entry(), which does not put the read object into
176 * the object pool, we cannot rely on a == b.
177 */
178 static int oid_eq(const struct object_id *a, const struct object_id *b)
179 {
180 if (!a && !b)
181 return 2;
182 return a && b && oidcmp(a, b) == 0;
183 }
184
185 enum rename_type {
186 RENAME_NORMAL = 0,
187 RENAME_DIR,
188 RENAME_DELETE,
189 RENAME_ONE_FILE_TO_ONE,
190 RENAME_ONE_FILE_TO_TWO,
191 RENAME_TWO_FILES_TO_ONE
192 };
193
194 struct rename_conflict_info {
195 enum rename_type rename_type;
196 struct diff_filepair *pair1;
197 struct diff_filepair *pair2;
198 const char *branch1;
199 const char *branch2;
200 struct stage_data *dst_entry1;
201 struct stage_data *dst_entry2;
202 struct diff_filespec ren1_other;
203 struct diff_filespec ren2_other;
204 };
205
206 /*
207 * Since we want to write the index eventually, we cannot reuse the index
208 * for these (temporary) data.
209 */
210 struct stage_data {
211 struct {
212 unsigned mode;
213 struct object_id oid;
214 } stages[4];
215 struct rename_conflict_info *rename_conflict_info;
216 unsigned processed:1;
217 };
218
219 static inline void setup_rename_conflict_info(enum rename_type rename_type,
220 struct diff_filepair *pair1,
221 struct diff_filepair *pair2,
222 const char *branch1,
223 const char *branch2,
224 struct stage_data *dst_entry1,
225 struct stage_data *dst_entry2,
226 struct merge_options *o,
227 struct stage_data *src_entry1,
228 struct stage_data *src_entry2)
229 {
230 struct rename_conflict_info *ci = xcalloc(1, sizeof(struct rename_conflict_info));
231 ci->rename_type = rename_type;
232 ci->pair1 = pair1;
233 ci->branch1 = branch1;
234 ci->branch2 = branch2;
235
236 ci->dst_entry1 = dst_entry1;
237 dst_entry1->rename_conflict_info = ci;
238 dst_entry1->processed = 0;
239
240 assert(!pair2 == !dst_entry2);
241 if (dst_entry2) {
242 ci->dst_entry2 = dst_entry2;
243 ci->pair2 = pair2;
244 dst_entry2->rename_conflict_info = ci;
245 }
246
247 if (rename_type == RENAME_TWO_FILES_TO_ONE) {
248 /*
249 * For each rename, there could have been
250 * modifications on the side of history where that
251 * file was not renamed.
252 */
253 int ostage1 = o->branch1 == branch1 ? 3 : 2;
254 int ostage2 = ostage1 ^ 1;
255
256 ci->ren1_other.path = pair1->one->path;
257 oidcpy(&ci->ren1_other.oid, &src_entry1->stages[ostage1].oid);
258 ci->ren1_other.mode = src_entry1->stages[ostage1].mode;
259
260 ci->ren2_other.path = pair2->one->path;
261 oidcpy(&ci->ren2_other.oid, &src_entry2->stages[ostage2].oid);
262 ci->ren2_other.mode = src_entry2->stages[ostage2].mode;
263 }
264 }
265
266 static int show(struct merge_options *o, int v)
267 {
268 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
269 }
270
271 __attribute__((format (printf, 3, 4)))
272 static void output(struct merge_options *o, int v, const char *fmt, ...)
273 {
274 va_list ap;
275
276 if (!show(o, v))
277 return;
278
279 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
280
281 va_start(ap, fmt);
282 strbuf_vaddf(&o->obuf, fmt, ap);
283 va_end(ap);
284
285 strbuf_addch(&o->obuf, '\n');
286 if (!o->buffer_output)
287 flush_output(o);
288 }
289
290 static void output_commit_title(struct merge_options *o, struct commit *commit)
291 {
292 struct merge_remote_desc *desc;
293
294 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
295 desc = merge_remote_util(commit);
296 if (desc)
297 strbuf_addf(&o->obuf, "virtual %s\n", desc->name);
298 else {
299 strbuf_add_unique_abbrev(&o->obuf, &commit->object.oid,
300 DEFAULT_ABBREV);
301 strbuf_addch(&o->obuf, ' ');
302 if (parse_commit(commit) != 0)
303 strbuf_addstr(&o->obuf, _("(bad commit)\n"));
304 else {
305 const char *title;
306 const char *msg = get_commit_buffer(commit, NULL);
307 int len = find_commit_subject(msg, &title);
308 if (len)
309 strbuf_addf(&o->obuf, "%.*s\n", len, title);
310 unuse_commit_buffer(commit, msg);
311 }
312 }
313 flush_output(o);
314 }
315
316 static int add_cacheinfo(struct merge_options *o,
317 unsigned int mode, const struct object_id *oid,
318 const char *path, int stage, int refresh, int options)
319 {
320 struct cache_entry *ce;
321 int ret;
322
323 ce = make_cache_entry(mode, oid ? oid->hash : null_sha1, path, stage, 0);
324 if (!ce)
325 return err(o, _("add_cacheinfo failed for path '%s'; merge aborting."), path);
326
327 ret = add_cache_entry(ce, options);
328 if (refresh) {
329 struct cache_entry *nce;
330
331 nce = refresh_cache_entry(ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
332 if (!nce)
333 return err(o, _("add_cacheinfo failed to refresh for path '%s'; merge aborting."), path);
334 if (nce != ce)
335 ret = add_cache_entry(nce, options);
336 }
337 return ret;
338 }
339
340 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
341 {
342 parse_tree(tree);
343 init_tree_desc(desc, tree->buffer, tree->size);
344 }
345
346 static int unpack_trees_start(struct merge_options *o,
347 struct tree *common,
348 struct tree *head,
349 struct tree *merge)
350 {
351 int rc;
352 struct tree_desc t[3];
353 struct index_state tmp_index = { NULL };
354
355 memset(&o->unpack_opts, 0, sizeof(o->unpack_opts));
356 if (o->call_depth)
357 o->unpack_opts.index_only = 1;
358 else
359 o->unpack_opts.update = 1;
360 o->unpack_opts.merge = 1;
361 o->unpack_opts.head_idx = 2;
362 o->unpack_opts.fn = threeway_merge;
363 o->unpack_opts.src_index = &the_index;
364 o->unpack_opts.dst_index = &tmp_index;
365 o->unpack_opts.aggressive = !merge_detect_rename(o);
366 setup_unpack_trees_porcelain(&o->unpack_opts, "merge");
367
368 init_tree_desc_from_tree(t+0, common);
369 init_tree_desc_from_tree(t+1, head);
370 init_tree_desc_from_tree(t+2, merge);
371
372 rc = unpack_trees(3, t, &o->unpack_opts);
373 cache_tree_free(&active_cache_tree);
374
375 /*
376 * Update the_index to match the new results, AFTER saving a copy
377 * in o->orig_index. Update src_index to point to the saved copy.
378 * (verify_uptodate() checks src_index, and the original index is
379 * the one that had the necessary modification timestamps.)
380 */
381 o->orig_index = the_index;
382 the_index = tmp_index;
383 o->unpack_opts.src_index = &o->orig_index;
384
385 return rc;
386 }
387
388 static void unpack_trees_finish(struct merge_options *o)
389 {
390 discard_index(&o->orig_index);
391 clear_unpack_trees_porcelain(&o->unpack_opts);
392 }
393
394 struct tree *write_tree_from_memory(struct merge_options *o)
395 {
396 struct tree *result = NULL;
397
398 if (unmerged_cache()) {
399 int i;
400 fprintf(stderr, "BUG: There are unmerged index entries:\n");
401 for (i = 0; i < active_nr; i++) {
402 const struct cache_entry *ce = active_cache[i];
403 if (ce_stage(ce))
404 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
405 (int)ce_namelen(ce), ce->name);
406 }
407 BUG("unmerged index entries in merge-recursive.c");
408 }
409
410 if (!active_cache_tree)
411 active_cache_tree = cache_tree();
412
413 if (!cache_tree_fully_valid(active_cache_tree) &&
414 cache_tree_update(&the_index, 0) < 0) {
415 err(o, _("error building trees"));
416 return NULL;
417 }
418
419 result = lookup_tree(the_repository, &active_cache_tree->oid);
420
421 return result;
422 }
423
424 static int save_files_dirs(const struct object_id *oid,
425 struct strbuf *base, const char *path,
426 unsigned int mode, int stage, void *context)
427 {
428 struct path_hashmap_entry *entry;
429 int baselen = base->len;
430 struct merge_options *o = context;
431
432 strbuf_addstr(base, path);
433
434 FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
435 hashmap_entry_init(entry, path_hash(entry->path));
436 hashmap_add(&o->current_file_dir_set, entry);
437
438 strbuf_setlen(base, baselen);
439 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
440 }
441
442 static void get_files_dirs(struct merge_options *o, struct tree *tree)
443 {
444 struct pathspec match_all;
445 memset(&match_all, 0, sizeof(match_all));
446 read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
447 }
448
449 static int get_tree_entry_if_blob(const struct object_id *tree,
450 const char *path,
451 struct object_id *hashy,
452 unsigned int *mode_o)
453 {
454 int ret;
455
456 ret = get_tree_entry(tree, path, hashy, mode_o);
457 if (S_ISDIR(*mode_o)) {
458 oidcpy(hashy, &null_oid);
459 *mode_o = 0;
460 }
461 return ret;
462 }
463
464 /*
465 * Returns an index_entry instance which doesn't have to correspond to
466 * a real cache entry in Git's index.
467 */
468 static struct stage_data *insert_stage_data(const char *path,
469 struct tree *o, struct tree *a, struct tree *b,
470 struct string_list *entries)
471 {
472 struct string_list_item *item;
473 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
474 get_tree_entry_if_blob(&o->object.oid, path,
475 &e->stages[1].oid, &e->stages[1].mode);
476 get_tree_entry_if_blob(&a->object.oid, path,
477 &e->stages[2].oid, &e->stages[2].mode);
478 get_tree_entry_if_blob(&b->object.oid, path,
479 &e->stages[3].oid, &e->stages[3].mode);
480 item = string_list_insert(entries, path);
481 item->util = e;
482 return e;
483 }
484
485 /*
486 * Create a dictionary mapping file names to stage_data objects. The
487 * dictionary contains one entry for every path with a non-zero stage entry.
488 */
489 static struct string_list *get_unmerged(void)
490 {
491 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
492 int i;
493
494 unmerged->strdup_strings = 1;
495
496 for (i = 0; i < active_nr; i++) {
497 struct string_list_item *item;
498 struct stage_data *e;
499 const struct cache_entry *ce = active_cache[i];
500 if (!ce_stage(ce))
501 continue;
502
503 item = string_list_lookup(unmerged, ce->name);
504 if (!item) {
505 item = string_list_insert(unmerged, ce->name);
506 item->util = xcalloc(1, sizeof(struct stage_data));
507 }
508 e = item->util;
509 e->stages[ce_stage(ce)].mode = ce->ce_mode;
510 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
511 }
512
513 return unmerged;
514 }
515
516 static int string_list_df_name_compare(const char *one, const char *two)
517 {
518 int onelen = strlen(one);
519 int twolen = strlen(two);
520 /*
521 * Here we only care that entries for D/F conflicts are
522 * adjacent, in particular with the file of the D/F conflict
523 * appearing before files below the corresponding directory.
524 * The order of the rest of the list is irrelevant for us.
525 *
526 * To achieve this, we sort with df_name_compare and provide
527 * the mode S_IFDIR so that D/F conflicts will sort correctly.
528 * We use the mode S_IFDIR for everything else for simplicity,
529 * since in other cases any changes in their order due to
530 * sorting cause no problems for us.
531 */
532 int cmp = df_name_compare(one, onelen, S_IFDIR,
533 two, twolen, S_IFDIR);
534 /*
535 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
536 * that 'foo' comes before 'foo/bar'.
537 */
538 if (cmp)
539 return cmp;
540 return onelen - twolen;
541 }
542
543 static void record_df_conflict_files(struct merge_options *o,
544 struct string_list *entries)
545 {
546 /* If there is a D/F conflict and the file for such a conflict
547 * currently exist in the working tree, we want to allow it to be
548 * removed to make room for the corresponding directory if needed.
549 * The files underneath the directories of such D/F conflicts will
550 * be processed before the corresponding file involved in the D/F
551 * conflict. If the D/F directory ends up being removed by the
552 * merge, then we won't have to touch the D/F file. If the D/F
553 * directory needs to be written to the working copy, then the D/F
554 * file will simply be removed (in make_room_for_path()) to make
555 * room for the necessary paths. Note that if both the directory
556 * and the file need to be present, then the D/F file will be
557 * reinstated with a new unique name at the time it is processed.
558 */
559 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
560 const char *last_file = NULL;
561 int last_len = 0;
562 int i;
563
564 /*
565 * If we're merging merge-bases, we don't want to bother with
566 * any working directory changes.
567 */
568 if (o->call_depth)
569 return;
570
571 /* Ensure D/F conflicts are adjacent in the entries list. */
572 for (i = 0; i < entries->nr; i++) {
573 struct string_list_item *next = &entries->items[i];
574 string_list_append(&df_sorted_entries, next->string)->util =
575 next->util;
576 }
577 df_sorted_entries.cmp = string_list_df_name_compare;
578 string_list_sort(&df_sorted_entries);
579
580 string_list_clear(&o->df_conflict_file_set, 1);
581 for (i = 0; i < df_sorted_entries.nr; i++) {
582 const char *path = df_sorted_entries.items[i].string;
583 int len = strlen(path);
584 struct stage_data *e = df_sorted_entries.items[i].util;
585
586 /*
587 * Check if last_file & path correspond to a D/F conflict;
588 * i.e. whether path is last_file+'/'+<something>.
589 * If so, record that it's okay to remove last_file to make
590 * room for path and friends if needed.
591 */
592 if (last_file &&
593 len > last_len &&
594 memcmp(path, last_file, last_len) == 0 &&
595 path[last_len] == '/') {
596 string_list_insert(&o->df_conflict_file_set, last_file);
597 }
598
599 /*
600 * Determine whether path could exist as a file in the
601 * working directory as a possible D/F conflict. This
602 * will only occur when it exists in stage 2 as a
603 * file.
604 */
605 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
606 last_file = path;
607 last_len = len;
608 } else {
609 last_file = NULL;
610 }
611 }
612 string_list_clear(&df_sorted_entries, 0);
613 }
614
615 struct rename {
616 struct diff_filepair *pair;
617 /*
618 * Purpose of src_entry and dst_entry:
619 *
620 * If 'before' is renamed to 'after' then src_entry will contain
621 * the versions of 'before' from the merge_base, HEAD, and MERGE in
622 * stages 1, 2, and 3; dst_entry will contain the respective
623 * versions of 'after' in corresponding locations. Thus, we have a
624 * total of six modes and oids, though some will be null. (Stage 0
625 * is ignored; we're interested in handling conflicts.)
626 *
627 * Since we don't turn on break-rewrites by default, neither
628 * src_entry nor dst_entry can have all three of their stages have
629 * non-null oids, meaning at most four of the six will be non-null.
630 * Also, since this is a rename, both src_entry and dst_entry will
631 * have at least one non-null oid, meaning at least two will be
632 * non-null. Of the six oids, a typical rename will have three be
633 * non-null. Only two implies a rename/delete, and four implies a
634 * rename/add.
635 */
636 struct stage_data *src_entry;
637 struct stage_data *dst_entry;
638 unsigned add_turned_into_rename:1;
639 unsigned processed:1;
640 };
641
642 static int update_stages(struct merge_options *opt, const char *path,
643 const struct diff_filespec *o,
644 const struct diff_filespec *a,
645 const struct diff_filespec *b)
646 {
647
648 /*
649 * NOTE: It is usually a bad idea to call update_stages on a path
650 * before calling update_file on that same path, since it can
651 * sometimes lead to spurious "refusing to lose untracked file..."
652 * messages from update_file (via make_room_for path via
653 * would_lose_untracked). Instead, reverse the order of the calls
654 * (executing update_file first and then update_stages).
655 */
656 int clear = 1;
657 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
658 if (clear)
659 if (remove_file_from_cache(path))
660 return -1;
661 if (o)
662 if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options))
663 return -1;
664 if (a)
665 if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options))
666 return -1;
667 if (b)
668 if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options))
669 return -1;
670 return 0;
671 }
672
673 static int update_stages_for_stage_data(struct merge_options *opt,
674 const char *path,
675 const struct stage_data *stage_data)
676 {
677 struct diff_filespec o, a, b;
678
679 o.mode = stage_data->stages[1].mode;
680 oidcpy(&o.oid, &stage_data->stages[1].oid);
681
682 a.mode = stage_data->stages[2].mode;
683 oidcpy(&a.oid, &stage_data->stages[2].oid);
684
685 b.mode = stage_data->stages[3].mode;
686 oidcpy(&b.oid, &stage_data->stages[3].oid);
687
688 return update_stages(opt, path,
689 is_null_oid(&o.oid) ? NULL : &o,
690 is_null_oid(&a.oid) ? NULL : &a,
691 is_null_oid(&b.oid) ? NULL : &b);
692 }
693
694 static void update_entry(struct stage_data *entry,
695 struct diff_filespec *o,
696 struct diff_filespec *a,
697 struct diff_filespec *b)
698 {
699 entry->processed = 0;
700 entry->stages[1].mode = o->mode;
701 entry->stages[2].mode = a->mode;
702 entry->stages[3].mode = b->mode;
703 oidcpy(&entry->stages[1].oid, &o->oid);
704 oidcpy(&entry->stages[2].oid, &a->oid);
705 oidcpy(&entry->stages[3].oid, &b->oid);
706 }
707
708 static int remove_file(struct merge_options *o, int clean,
709 const char *path, int no_wd)
710 {
711 int update_cache = o->call_depth || clean;
712 int update_working_directory = !o->call_depth && !no_wd;
713
714 if (update_cache) {
715 if (remove_file_from_cache(path))
716 return -1;
717 }
718 if (update_working_directory) {
719 if (ignore_case) {
720 struct cache_entry *ce;
721 ce = cache_file_exists(path, strlen(path), ignore_case);
722 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
723 return 0;
724 }
725 if (remove_path(path))
726 return -1;
727 }
728 return 0;
729 }
730
731 /* add a string to a strbuf, but converting "/" to "_" */
732 static void add_flattened_path(struct strbuf *out, const char *s)
733 {
734 size_t i = out->len;
735 strbuf_addstr(out, s);
736 for (; i < out->len; i++)
737 if (out->buf[i] == '/')
738 out->buf[i] = '_';
739 }
740
741 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
742 {
743 struct path_hashmap_entry *entry;
744 struct strbuf newpath = STRBUF_INIT;
745 int suffix = 0;
746 size_t base_len;
747
748 strbuf_addf(&newpath, "%s~", path);
749 add_flattened_path(&newpath, branch);
750
751 base_len = newpath.len;
752 while (hashmap_get_from_hash(&o->current_file_dir_set,
753 path_hash(newpath.buf), newpath.buf) ||
754 (!o->call_depth && file_exists(newpath.buf))) {
755 strbuf_setlen(&newpath, base_len);
756 strbuf_addf(&newpath, "_%d", suffix++);
757 }
758
759 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
760 hashmap_entry_init(entry, path_hash(entry->path));
761 hashmap_add(&o->current_file_dir_set, entry);
762 return strbuf_detach(&newpath, NULL);
763 }
764
765 /**
766 * Check whether a directory in the index is in the way of an incoming
767 * file. Return 1 if so. If check_working_copy is non-zero, also
768 * check the working directory. If empty_ok is non-zero, also return
769 * 0 in the case where the working-tree dir exists but is empty.
770 */
771 static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
772 {
773 int pos;
774 struct strbuf dirpath = STRBUF_INIT;
775 struct stat st;
776
777 strbuf_addstr(&dirpath, path);
778 strbuf_addch(&dirpath, '/');
779
780 pos = cache_name_pos(dirpath.buf, dirpath.len);
781
782 if (pos < 0)
783 pos = -1 - pos;
784 if (pos < active_nr &&
785 !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) {
786 strbuf_release(&dirpath);
787 return 1;
788 }
789
790 strbuf_release(&dirpath);
791 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
792 !(empty_ok && is_empty_dir(path));
793 }
794
795 /*
796 * Returns whether path was tracked in the index before the merge started,
797 * and its oid and mode match the specified values
798 */
799 static int was_tracked_and_matches(struct merge_options *o, const char *path,
800 const struct object_id *oid, unsigned mode)
801 {
802 int pos = index_name_pos(&o->orig_index, path, strlen(path));
803 struct cache_entry *ce;
804
805 if (0 > pos)
806 /* we were not tracking this path before the merge */
807 return 0;
808
809 /* See if the file we were tracking before matches */
810 ce = o->orig_index.cache[pos];
811 return (oid_eq(&ce->oid, oid) && ce->ce_mode == mode);
812 }
813
814 /*
815 * Returns whether path was tracked in the index before the merge started
816 */
817 static int was_tracked(struct merge_options *o, const char *path)
818 {
819 int pos = index_name_pos(&o->orig_index, path, strlen(path));
820
821 if (0 <= pos)
822 /* we were tracking this path before the merge */
823 return 1;
824
825 return 0;
826 }
827
828 static int would_lose_untracked(const char *path)
829 {
830 /*
831 * This may look like it can be simplified to:
832 * return !was_tracked(o, path) && file_exists(path)
833 * but it can't. This function needs to know whether path was in
834 * the working tree due to EITHER having been tracked in the index
835 * before the merge OR having been put into the working copy and
836 * index by unpack_trees(). Due to that either-or requirement, we
837 * check the current index instead of the original one.
838 *
839 * Note that we do not need to worry about merge-recursive itself
840 * updating the index after unpack_trees() and before calling this
841 * function, because we strictly require all code paths in
842 * merge-recursive to update the working tree first and the index
843 * second. Doing otherwise would break
844 * update_file()/would_lose_untracked(); see every comment in this
845 * file which mentions "update_stages".
846 */
847 int pos = cache_name_pos(path, strlen(path));
848
849 if (pos < 0)
850 pos = -1 - pos;
851 while (pos < active_nr &&
852 !strcmp(path, active_cache[pos]->name)) {
853 /*
854 * If stage #0, it is definitely tracked.
855 * If it has stage #2 then it was tracked
856 * before this merge started. All other
857 * cases the path was not tracked.
858 */
859 switch (ce_stage(active_cache[pos])) {
860 case 0:
861 case 2:
862 return 0;
863 }
864 pos++;
865 }
866 return file_exists(path);
867 }
868
869 static int was_dirty(struct merge_options *o, const char *path)
870 {
871 struct cache_entry *ce;
872 int dirty = 1;
873
874 if (o->call_depth || !was_tracked(o, path))
875 return !dirty;
876
877 ce = index_file_exists(o->unpack_opts.src_index,
878 path, strlen(path), ignore_case);
879 dirty = verify_uptodate(ce, &o->unpack_opts) != 0;
880 return dirty;
881 }
882
883 static int make_room_for_path(struct merge_options *o, const char *path)
884 {
885 int status, i;
886 const char *msg = _("failed to create path '%s'%s");
887
888 /* Unlink any D/F conflict files that are in the way */
889 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
890 const char *df_path = o->df_conflict_file_set.items[i].string;
891 size_t pathlen = strlen(path);
892 size_t df_pathlen = strlen(df_path);
893 if (df_pathlen < pathlen &&
894 path[df_pathlen] == '/' &&
895 strncmp(path, df_path, df_pathlen) == 0) {
896 output(o, 3,
897 _("Removing %s to make room for subdirectory\n"),
898 df_path);
899 unlink(df_path);
900 unsorted_string_list_delete_item(&o->df_conflict_file_set,
901 i, 0);
902 break;
903 }
904 }
905
906 /* Make sure leading directories are created */
907 status = safe_create_leading_directories_const(path);
908 if (status) {
909 if (status == SCLD_EXISTS)
910 /* something else exists */
911 return err(o, msg, path, _(": perhaps a D/F conflict?"));
912 return err(o, msg, path, "");
913 }
914
915 /*
916 * Do not unlink a file in the work tree if we are not
917 * tracking it.
918 */
919 if (would_lose_untracked(path))
920 return err(o, _("refusing to lose untracked file at '%s'"),
921 path);
922
923 /* Successful unlink is good.. */
924 if (!unlink(path))
925 return 0;
926 /* .. and so is no existing file */
927 if (errno == ENOENT)
928 return 0;
929 /* .. but not some other error (who really cares what?) */
930 return err(o, msg, path, _(": perhaps a D/F conflict?"));
931 }
932
933 static int update_file_flags(struct merge_options *o,
934 const struct object_id *oid,
935 unsigned mode,
936 const char *path,
937 int update_cache,
938 int update_wd)
939 {
940 int ret = 0;
941
942 if (o->call_depth)
943 update_wd = 0;
944
945 if (update_wd) {
946 enum object_type type;
947 void *buf;
948 unsigned long size;
949
950 if (S_ISGITLINK(mode)) {
951 /*
952 * We may later decide to recursively descend into
953 * the submodule directory and update its index
954 * and/or work tree, but we do not do that now.
955 */
956 update_wd = 0;
957 goto update_index;
958 }
959
960 buf = read_object_file(oid, &type, &size);
961 if (!buf)
962 return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path);
963 if (type != OBJ_BLOB) {
964 ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path);
965 goto free_buf;
966 }
967 if (S_ISREG(mode)) {
968 struct strbuf strbuf = STRBUF_INIT;
969 if (convert_to_working_tree(path, buf, size, &strbuf)) {
970 free(buf);
971 size = strbuf.len;
972 buf = strbuf_detach(&strbuf, NULL);
973 }
974 }
975
976 if (make_room_for_path(o, path) < 0) {
977 update_wd = 0;
978 goto free_buf;
979 }
980 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
981 int fd;
982 if (mode & 0100)
983 mode = 0777;
984 else
985 mode = 0666;
986 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
987 if (fd < 0) {
988 ret = err(o, _("failed to open '%s': %s"),
989 path, strerror(errno));
990 goto free_buf;
991 }
992 write_in_full(fd, buf, size);
993 close(fd);
994 } else if (S_ISLNK(mode)) {
995 char *lnk = xmemdupz(buf, size);
996 safe_create_leading_directories_const(path);
997 unlink(path);
998 if (symlink(lnk, path))
999 ret = err(o, _("failed to symlink '%s': %s"),
1000 path, strerror(errno));
1001 free(lnk);
1002 } else
1003 ret = err(o,
1004 _("do not know what to do with %06o %s '%s'"),
1005 mode, oid_to_hex(oid), path);
1006 free_buf:
1007 free(buf);
1008 }
1009 update_index:
1010 if (!ret && update_cache)
1011 if (add_cacheinfo(o, mode, oid, path, 0, update_wd,
1012 ADD_CACHE_OK_TO_ADD))
1013 return -1;
1014 return ret;
1015 }
1016
1017 static int update_file(struct merge_options *o,
1018 int clean,
1019 const struct object_id *oid,
1020 unsigned mode,
1021 const char *path)
1022 {
1023 return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth);
1024 }
1025
1026 /* Low level file merging, update and removal */
1027
1028 struct merge_file_info {
1029 struct object_id oid;
1030 unsigned mode;
1031 unsigned clean:1,
1032 merge:1;
1033 };
1034
1035 static int merge_3way(struct merge_options *o,
1036 mmbuffer_t *result_buf,
1037 const struct diff_filespec *one,
1038 const struct diff_filespec *a,
1039 const struct diff_filespec *b,
1040 const char *branch1,
1041 const char *branch2)
1042 {
1043 mmfile_t orig, src1, src2;
1044 struct ll_merge_options ll_opts = {0};
1045 char *base_name, *name1, *name2;
1046 int merge_status;
1047
1048 ll_opts.renormalize = o->renormalize;
1049 ll_opts.xdl_opts = o->xdl_opts;
1050
1051 if (o->call_depth) {
1052 ll_opts.virtual_ancestor = 1;
1053 ll_opts.variant = 0;
1054 } else {
1055 switch (o->recursive_variant) {
1056 case MERGE_RECURSIVE_OURS:
1057 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
1058 break;
1059 case MERGE_RECURSIVE_THEIRS:
1060 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
1061 break;
1062 default:
1063 ll_opts.variant = 0;
1064 break;
1065 }
1066 }
1067
1068 if (strcmp(a->path, b->path) ||
1069 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
1070 base_name = o->ancestor == NULL ? NULL :
1071 mkpathdup("%s:%s", o->ancestor, one->path);
1072 name1 = mkpathdup("%s:%s", branch1, a->path);
1073 name2 = mkpathdup("%s:%s", branch2, b->path);
1074 } else {
1075 base_name = o->ancestor == NULL ? NULL :
1076 mkpathdup("%s", o->ancestor);
1077 name1 = mkpathdup("%s", branch1);
1078 name2 = mkpathdup("%s", branch2);
1079 }
1080
1081 read_mmblob(&orig, &one->oid);
1082 read_mmblob(&src1, &a->oid);
1083 read_mmblob(&src2, &b->oid);
1084
1085 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
1086 &src1, name1, &src2, name2, &ll_opts);
1087
1088 free(base_name);
1089 free(name1);
1090 free(name2);
1091 free(orig.ptr);
1092 free(src1.ptr);
1093 free(src2.ptr);
1094 return merge_status;
1095 }
1096
1097 static int find_first_merges(struct object_array *result, const char *path,
1098 struct commit *a, struct commit *b)
1099 {
1100 int i, j;
1101 struct object_array merges = OBJECT_ARRAY_INIT;
1102 struct commit *commit;
1103 int contains_another;
1104
1105 char merged_revision[42];
1106 const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1107 "--all", merged_revision, NULL };
1108 struct rev_info revs;
1109 struct setup_revision_opt rev_opts;
1110
1111 memset(result, 0, sizeof(struct object_array));
1112 memset(&rev_opts, 0, sizeof(rev_opts));
1113
1114 /* get all revisions that merge commit a */
1115 xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1116 oid_to_hex(&a->object.oid));
1117 init_revisions(&revs, NULL);
1118 rev_opts.submodule = path;
1119 /* FIXME: can't handle linked worktrees in submodules yet */
1120 revs.single_worktree = path != NULL;
1121 setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1122
1123 /* save all revisions from the above list that contain b */
1124 if (prepare_revision_walk(&revs))
1125 die("revision walk setup failed");
1126 while ((commit = get_revision(&revs)) != NULL) {
1127 struct object *o = &(commit->object);
1128 if (in_merge_bases(b, commit))
1129 add_object_array(o, NULL, &merges);
1130 }
1131 reset_revision_walk();
1132
1133 /* Now we've got all merges that contain a and b. Prune all
1134 * merges that contain another found merge and save them in
1135 * result.
1136 */
1137 for (i = 0; i < merges.nr; i++) {
1138 struct commit *m1 = (struct commit *) merges.objects[i].item;
1139
1140 contains_another = 0;
1141 for (j = 0; j < merges.nr; j++) {
1142 struct commit *m2 = (struct commit *) merges.objects[j].item;
1143 if (i != j && in_merge_bases(m2, m1)) {
1144 contains_another = 1;
1145 break;
1146 }
1147 }
1148
1149 if (!contains_another)
1150 add_object_array(merges.objects[i].item, NULL, result);
1151 }
1152
1153 object_array_clear(&merges);
1154 return result->nr;
1155 }
1156
1157 static void print_commit(struct commit *commit)
1158 {
1159 struct strbuf sb = STRBUF_INIT;
1160 struct pretty_print_context ctx = {0};
1161 ctx.date_mode.type = DATE_NORMAL;
1162 format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1163 fprintf(stderr, "%s\n", sb.buf);
1164 strbuf_release(&sb);
1165 }
1166
1167 static int merge_submodule(struct merge_options *o,
1168 struct object_id *result, const char *path,
1169 const struct object_id *base, const struct object_id *a,
1170 const struct object_id *b)
1171 {
1172 struct commit *commit_base, *commit_a, *commit_b;
1173 int parent_count;
1174 struct object_array merges;
1175
1176 int i;
1177 int search = !o->call_depth;
1178
1179 /* store a in result in case we fail */
1180 oidcpy(result, a);
1181
1182 /* we can not handle deletion conflicts */
1183 if (is_null_oid(base))
1184 return 0;
1185 if (is_null_oid(a))
1186 return 0;
1187 if (is_null_oid(b))
1188 return 0;
1189
1190 if (add_submodule_odb(path)) {
1191 output(o, 1, _("Failed to merge submodule %s (not checked out)"), path);
1192 return 0;
1193 }
1194
1195 if (!(commit_base = lookup_commit_reference(base)) ||
1196 !(commit_a = lookup_commit_reference(a)) ||
1197 !(commit_b = lookup_commit_reference(b))) {
1198 output(o, 1, _("Failed to merge submodule %s (commits not present)"), path);
1199 return 0;
1200 }
1201
1202 /* check whether both changes are forward */
1203 if (!in_merge_bases(commit_base, commit_a) ||
1204 !in_merge_bases(commit_base, commit_b)) {
1205 output(o, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
1206 return 0;
1207 }
1208
1209 /* Case #1: a is contained in b or vice versa */
1210 if (in_merge_bases(commit_a, commit_b)) {
1211 oidcpy(result, b);
1212 if (show(o, 3)) {
1213 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1214 output_commit_title(o, commit_b);
1215 } else if (show(o, 2))
1216 output(o, 2, _("Fast-forwarding submodule %s"), path);
1217 else
1218 ; /* no output */
1219
1220 return 1;
1221 }
1222 if (in_merge_bases(commit_b, commit_a)) {
1223 oidcpy(result, a);
1224 if (show(o, 3)) {
1225 output(o, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1226 output_commit_title(o, commit_a);
1227 } else if (show(o, 2))
1228 output(o, 2, _("Fast-forwarding submodule %s"), path);
1229 else
1230 ; /* no output */
1231
1232 return 1;
1233 }
1234
1235 /*
1236 * Case #2: There are one or more merges that contain a and b in
1237 * the submodule. If there is only one, then present it as a
1238 * suggestion to the user, but leave it marked unmerged so the
1239 * user needs to confirm the resolution.
1240 */
1241
1242 /* Skip the search if makes no sense to the calling context. */
1243 if (!search)
1244 return 0;
1245
1246 /* find commit which merges them */
1247 parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1248 switch (parent_count) {
1249 case 0:
1250 output(o, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
1251 break;
1252
1253 case 1:
1254 output(o, 1, _("Failed to merge submodule %s (not fast-forward)"), path);
1255 output(o, 2, _("Found a possible merge resolution for the submodule:\n"));
1256 print_commit((struct commit *) merges.objects[0].item);
1257 output(o, 2, _(
1258 "If this is correct simply add it to the index "
1259 "for example\n"
1260 "by using:\n\n"
1261 " git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1262 "which will accept this suggestion.\n"),
1263 oid_to_hex(&merges.objects[0].item->oid), path);
1264 break;
1265
1266 default:
1267 output(o, 1, _("Failed to merge submodule %s (multiple merges found)"), path);
1268 for (i = 0; i < merges.nr; i++)
1269 print_commit((struct commit *) merges.objects[i].item);
1270 }
1271
1272 object_array_clear(&merges);
1273 return 0;
1274 }
1275
1276 static int merge_file_1(struct merge_options *o,
1277 const struct diff_filespec *one,
1278 const struct diff_filespec *a,
1279 const struct diff_filespec *b,
1280 const char *filename,
1281 const char *branch1,
1282 const char *branch2,
1283 struct merge_file_info *result)
1284 {
1285 result->merge = 0;
1286 result->clean = 1;
1287
1288 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
1289 result->clean = 0;
1290 if (S_ISREG(a->mode)) {
1291 result->mode = a->mode;
1292 oidcpy(&result->oid, &a->oid);
1293 } else {
1294 result->mode = b->mode;
1295 oidcpy(&result->oid, &b->oid);
1296 }
1297 } else {
1298 if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid))
1299 result->merge = 1;
1300
1301 /*
1302 * Merge modes
1303 */
1304 if (a->mode == b->mode || a->mode == one->mode)
1305 result->mode = b->mode;
1306 else {
1307 result->mode = a->mode;
1308 if (b->mode != one->mode) {
1309 result->clean = 0;
1310 result->merge = 1;
1311 }
1312 }
1313
1314 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid))
1315 oidcpy(&result->oid, &b->oid);
1316 else if (oid_eq(&b->oid, &one->oid))
1317 oidcpy(&result->oid, &a->oid);
1318 else if (S_ISREG(a->mode)) {
1319 mmbuffer_t result_buf;
1320 int ret = 0, merge_status;
1321
1322 merge_status = merge_3way(o, &result_buf, one, a, b,
1323 branch1, branch2);
1324
1325 if ((merge_status < 0) || !result_buf.ptr)
1326 ret = err(o, _("Failed to execute internal merge"));
1327
1328 if (!ret &&
1329 write_object_file(result_buf.ptr, result_buf.size,
1330 blob_type, &result->oid))
1331 ret = err(o, _("Unable to add %s to database"),
1332 a->path);
1333
1334 free(result_buf.ptr);
1335 if (ret)
1336 return ret;
1337 result->clean = (merge_status == 0);
1338 } else if (S_ISGITLINK(a->mode)) {
1339 result->clean = merge_submodule(o, &result->oid,
1340 one->path,
1341 &one->oid,
1342 &a->oid,
1343 &b->oid);
1344 } else if (S_ISLNK(a->mode)) {
1345 switch (o->recursive_variant) {
1346 case MERGE_RECURSIVE_NORMAL:
1347 oidcpy(&result->oid, &a->oid);
1348 if (!oid_eq(&a->oid, &b->oid))
1349 result->clean = 0;
1350 break;
1351 case MERGE_RECURSIVE_OURS:
1352 oidcpy(&result->oid, &a->oid);
1353 break;
1354 case MERGE_RECURSIVE_THEIRS:
1355 oidcpy(&result->oid, &b->oid);
1356 break;
1357 }
1358 } else
1359 BUG("unsupported object type in the tree");
1360 }
1361
1362 if (result->merge)
1363 output(o, 2, _("Auto-merging %s"), filename);
1364
1365 return 0;
1366 }
1367
1368 static int merge_file_special_markers(struct merge_options *o,
1369 const struct diff_filespec *one,
1370 const struct diff_filespec *a,
1371 const struct diff_filespec *b,
1372 const char *target_filename,
1373 const char *branch1,
1374 const char *filename1,
1375 const char *branch2,
1376 const char *filename2,
1377 struct merge_file_info *mfi)
1378 {
1379 char *side1 = NULL;
1380 char *side2 = NULL;
1381 int ret;
1382
1383 if (filename1)
1384 side1 = xstrfmt("%s:%s", branch1, filename1);
1385 if (filename2)
1386 side2 = xstrfmt("%s:%s", branch2, filename2);
1387
1388 ret = merge_file_1(o, one, a, b, target_filename,
1389 side1 ? side1 : branch1,
1390 side2 ? side2 : branch2, mfi);
1391
1392 free(side1);
1393 free(side2);
1394 return ret;
1395 }
1396
1397 static int merge_file_one(struct merge_options *o,
1398 const char *path,
1399 const struct object_id *o_oid, int o_mode,
1400 const struct object_id *a_oid, int a_mode,
1401 const struct object_id *b_oid, int b_mode,
1402 const char *branch1,
1403 const char *branch2,
1404 struct merge_file_info *mfi)
1405 {
1406 struct diff_filespec one, a, b;
1407
1408 one.path = a.path = b.path = (char *)path;
1409 oidcpy(&one.oid, o_oid);
1410 one.mode = o_mode;
1411 oidcpy(&a.oid, a_oid);
1412 a.mode = a_mode;
1413 oidcpy(&b.oid, b_oid);
1414 b.mode = b_mode;
1415 return merge_file_1(o, &one, &a, &b, path, branch1, branch2, mfi);
1416 }
1417
1418 static int conflict_rename_dir(struct merge_options *o,
1419 struct diff_filepair *pair,
1420 const char *rename_branch,
1421 const char *other_branch)
1422 {
1423 const struct diff_filespec *dest = pair->two;
1424
1425 if (!o->call_depth && would_lose_untracked(dest->path)) {
1426 char *alt_path = unique_path(o, dest->path, rename_branch);
1427
1428 output(o, 1, _("Error: Refusing to lose untracked file at %s; "
1429 "writing to %s instead."),
1430 dest->path, alt_path);
1431 /*
1432 * Write the file in worktree at alt_path, but not in the
1433 * index. Instead, write to dest->path for the index but
1434 * only at the higher appropriate stage.
1435 */
1436 if (update_file(o, 0, &dest->oid, dest->mode, alt_path))
1437 return -1;
1438 free(alt_path);
1439 return update_stages(o, dest->path, NULL,
1440 rename_branch == o->branch1 ? dest : NULL,
1441 rename_branch == o->branch1 ? NULL : dest);
1442 }
1443
1444 /* Update dest->path both in index and in worktree */
1445 if (update_file(o, 1, &dest->oid, dest->mode, dest->path))
1446 return -1;
1447 return 0;
1448 }
1449
1450 static int handle_change_delete(struct merge_options *o,
1451 const char *path, const char *old_path,
1452 const struct object_id *o_oid, int o_mode,
1453 const struct object_id *changed_oid,
1454 int changed_mode,
1455 const char *change_branch,
1456 const char *delete_branch,
1457 const char *change, const char *change_past)
1458 {
1459 char *alt_path = NULL;
1460 const char *update_path = path;
1461 int ret = 0;
1462
1463 if (dir_in_way(path, !o->call_depth, 0) ||
1464 (!o->call_depth && would_lose_untracked(path))) {
1465 update_path = alt_path = unique_path(o, path, change_branch);
1466 }
1467
1468 if (o->call_depth) {
1469 /*
1470 * We cannot arbitrarily accept either a_sha or b_sha as
1471 * correct; since there is no true "middle point" between
1472 * them, simply reuse the base version for virtual merge base.
1473 */
1474 ret = remove_file_from_cache(path);
1475 if (!ret)
1476 ret = update_file(o, 0, o_oid, o_mode, update_path);
1477 } else {
1478 if (!alt_path) {
1479 if (!old_path) {
1480 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1481 "and %s in %s. Version %s of %s left in tree."),
1482 change, path, delete_branch, change_past,
1483 change_branch, change_branch, path);
1484 } else {
1485 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1486 "and %s to %s in %s. Version %s of %s left in tree."),
1487 change, old_path, delete_branch, change_past, path,
1488 change_branch, change_branch, path);
1489 }
1490 } else {
1491 if (!old_path) {
1492 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1493 "and %s in %s. Version %s of %s left in tree at %s."),
1494 change, path, delete_branch, change_past,
1495 change_branch, change_branch, path, alt_path);
1496 } else {
1497 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1498 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1499 change, old_path, delete_branch, change_past, path,
1500 change_branch, change_branch, path, alt_path);
1501 }
1502 }
1503 /*
1504 * No need to call update_file() on path when change_branch ==
1505 * o->branch1 && !alt_path, since that would needlessly touch
1506 * path. We could call update_file_flags() with update_cache=0
1507 * and update_wd=0, but that's a no-op.
1508 */
1509 if (change_branch != o->branch1 || alt_path)
1510 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1511 }
1512 free(alt_path);
1513
1514 return ret;
1515 }
1516
1517 static int conflict_rename_delete(struct merge_options *o,
1518 struct diff_filepair *pair,
1519 const char *rename_branch,
1520 const char *delete_branch)
1521 {
1522 const struct diff_filespec *orig = pair->one;
1523 const struct diff_filespec *dest = pair->two;
1524
1525 if (handle_change_delete(o,
1526 o->call_depth ? orig->path : dest->path,
1527 o->call_depth ? NULL : orig->path,
1528 &orig->oid, orig->mode,
1529 &dest->oid, dest->mode,
1530 rename_branch, delete_branch,
1531 _("rename"), _("renamed")))
1532 return -1;
1533
1534 if (o->call_depth)
1535 return remove_file_from_cache(dest->path);
1536 else
1537 return update_stages(o, dest->path, NULL,
1538 rename_branch == o->branch1 ? dest : NULL,
1539 rename_branch == o->branch1 ? NULL : dest);
1540 }
1541
1542 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1543 struct stage_data *entry,
1544 int stage)
1545 {
1546 struct object_id *oid = &entry->stages[stage].oid;
1547 unsigned mode = entry->stages[stage].mode;
1548 if (mode == 0 || is_null_oid(oid))
1549 return NULL;
1550 oidcpy(&target->oid, oid);
1551 target->mode = mode;
1552 return target;
1553 }
1554
1555 static int handle_file(struct merge_options *o,
1556 struct diff_filespec *rename,
1557 int stage,
1558 struct rename_conflict_info *ci)
1559 {
1560 char *dst_name = rename->path;
1561 struct stage_data *dst_entry;
1562 const char *cur_branch, *other_branch;
1563 struct diff_filespec other;
1564 struct diff_filespec *add;
1565 int ret;
1566
1567 if (stage == 2) {
1568 dst_entry = ci->dst_entry1;
1569 cur_branch = ci->branch1;
1570 other_branch = ci->branch2;
1571 } else {
1572 dst_entry = ci->dst_entry2;
1573 cur_branch = ci->branch2;
1574 other_branch = ci->branch1;
1575 }
1576
1577 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1578 if (add) {
1579 int ren_src_was_dirty = was_dirty(o, rename->path);
1580 char *add_name = unique_path(o, rename->path, other_branch);
1581 if (update_file(o, 0, &add->oid, add->mode, add_name))
1582 return -1;
1583
1584 if (ren_src_was_dirty) {
1585 output(o, 1, _("Refusing to lose dirty file at %s"),
1586 rename->path);
1587 }
1588 /*
1589 * Because the double negatives somehow keep confusing me...
1590 * 1) update_wd iff !ren_src_was_dirty.
1591 * 2) no_wd iff !update_wd
1592 * 3) so, no_wd == !!ren_src_was_dirty == ren_src_was_dirty
1593 */
1594 remove_file(o, 0, rename->path, ren_src_was_dirty);
1595 dst_name = unique_path(o, rename->path, cur_branch);
1596 } else {
1597 if (dir_in_way(rename->path, !o->call_depth, 0)) {
1598 dst_name = unique_path(o, rename->path, cur_branch);
1599 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1600 rename->path, other_branch, dst_name);
1601 } else if (!o->call_depth &&
1602 would_lose_untracked(rename->path)) {
1603 dst_name = unique_path(o, rename->path, cur_branch);
1604 output(o, 1, _("Refusing to lose untracked file at %s; "
1605 "adding as %s instead"),
1606 rename->path, dst_name);
1607 }
1608 }
1609 if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name)))
1610 ; /* fall through, do allow dst_name to be released */
1611 else if (stage == 2)
1612 ret = update_stages(o, rename->path, NULL, rename, add);
1613 else
1614 ret = update_stages(o, rename->path, NULL, add, rename);
1615
1616 if (dst_name != rename->path)
1617 free(dst_name);
1618
1619 return ret;
1620 }
1621
1622 static int conflict_rename_rename_1to2(struct merge_options *o,
1623 struct rename_conflict_info *ci)
1624 {
1625 /* One file was renamed in both branches, but to different names. */
1626 struct diff_filespec *one = ci->pair1->one;
1627 struct diff_filespec *a = ci->pair1->two;
1628 struct diff_filespec *b = ci->pair2->two;
1629
1630 output(o, 1, _("CONFLICT (rename/rename): "
1631 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1632 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1633 one->path, a->path, ci->branch1,
1634 one->path, b->path, ci->branch2,
1635 o->call_depth ? _(" (left unresolved)") : "");
1636 if (o->call_depth) {
1637 struct merge_file_info mfi;
1638 struct diff_filespec other;
1639 struct diff_filespec *add;
1640 if (merge_file_one(o, one->path,
1641 &one->oid, one->mode,
1642 &a->oid, a->mode,
1643 &b->oid, b->mode,
1644 ci->branch1, ci->branch2, &mfi))
1645 return -1;
1646
1647 /*
1648 * FIXME: For rename/add-source conflicts (if we could detect
1649 * such), this is wrong. We should instead find a unique
1650 * pathname and then either rename the add-source file to that
1651 * unique path, or use that unique path instead of src here.
1652 */
1653 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1654 return -1;
1655
1656 /*
1657 * Above, we put the merged content at the merge-base's
1658 * path. Now we usually need to delete both a->path and
1659 * b->path. However, the rename on each side of the merge
1660 * could also be involved in a rename/add conflict. In
1661 * such cases, we should keep the added file around,
1662 * resolving the conflict at that path in its favor.
1663 */
1664 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1665 if (add) {
1666 if (update_file(o, 0, &add->oid, add->mode, a->path))
1667 return -1;
1668 }
1669 else
1670 remove_file_from_cache(a->path);
1671 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1672 if (add) {
1673 if (update_file(o, 0, &add->oid, add->mode, b->path))
1674 return -1;
1675 }
1676 else
1677 remove_file_from_cache(b->path);
1678 } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci))
1679 return -1;
1680
1681 return 0;
1682 }
1683
1684 static int conflict_rename_rename_2to1(struct merge_options *o,
1685 struct rename_conflict_info *ci)
1686 {
1687 /* Two files, a & b, were renamed to the same thing, c. */
1688 struct diff_filespec *a = ci->pair1->one;
1689 struct diff_filespec *b = ci->pair2->one;
1690 struct diff_filespec *c1 = ci->pair1->two;
1691 struct diff_filespec *c2 = ci->pair2->two;
1692 char *path = c1->path; /* == c2->path */
1693 char *path_side_1_desc;
1694 char *path_side_2_desc;
1695 struct merge_file_info mfi_c1;
1696 struct merge_file_info mfi_c2;
1697 int ret;
1698
1699 output(o, 1, _("CONFLICT (rename/rename): "
1700 "Rename %s->%s in %s. "
1701 "Rename %s->%s in %s"),
1702 a->path, c1->path, ci->branch1,
1703 b->path, c2->path, ci->branch2);
1704
1705 remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path));
1706 remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path));
1707
1708 path_side_1_desc = xstrfmt("%s (was %s)", path, a->path);
1709 path_side_2_desc = xstrfmt("%s (was %s)", path, b->path);
1710 if (merge_file_special_markers(o, a, c1, &ci->ren1_other,
1711 path_side_1_desc,
1712 o->branch1, c1->path,
1713 o->branch2, ci->ren1_other.path, &mfi_c1) ||
1714 merge_file_special_markers(o, b, &ci->ren2_other, c2,
1715 path_side_2_desc,
1716 o->branch1, ci->ren2_other.path,
1717 o->branch2, c2->path, &mfi_c2))
1718 return -1;
1719 free(path_side_1_desc);
1720 free(path_side_2_desc);
1721
1722 if (o->call_depth) {
1723 /*
1724 * If mfi_c1.clean && mfi_c2.clean, then it might make
1725 * sense to do a two-way merge of those results. But, I
1726 * think in all cases, it makes sense to have the virtual
1727 * merge base just undo the renames; they can be detected
1728 * again later for the non-recursive merge.
1729 */
1730 remove_file(o, 0, path, 0);
1731 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path);
1732 if (!ret)
1733 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1734 b->path);
1735 } else {
1736 char *new_path1 = unique_path(o, path, ci->branch1);
1737 char *new_path2 = unique_path(o, path, ci->branch2);
1738 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1739 a->path, new_path1, b->path, new_path2);
1740 if (was_dirty(o, path))
1741 output(o, 1, _("Refusing to lose dirty file at %s"),
1742 path);
1743 else if (would_lose_untracked(path))
1744 /*
1745 * Only way we get here is if both renames were from
1746 * a directory rename AND user had an untracked file
1747 * at the location where both files end up after the
1748 * two directory renames. See testcase 10d of t6043.
1749 */
1750 output(o, 1, _("Refusing to lose untracked file at "
1751 "%s, even though it's in the way."),
1752 path);
1753 else
1754 remove_file(o, 0, path, 0);
1755 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1);
1756 if (!ret)
1757 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1758 new_path2);
1759 /*
1760 * unpack_trees() actually populates the index for us for
1761 * "normal" rename/rename(2to1) situtations so that the
1762 * correct entries are at the higher stages, which would
1763 * make the call below to update_stages_for_stage_data
1764 * unnecessary. However, if either of the renames came
1765 * from a directory rename, then unpack_trees() will not
1766 * have gotten the right data loaded into the index, so we
1767 * need to do so now. (While it'd be tempting to move this
1768 * call to update_stages_for_stage_data() to
1769 * apply_directory_rename_modifications(), that would break
1770 * our intermediate calls to would_lose_untracked() since
1771 * those rely on the current in-memory index. See also the
1772 * big "NOTE" in update_stages()).
1773 */
1774 if (update_stages_for_stage_data(o, path, ci->dst_entry1))
1775 ret = -1;
1776
1777 free(new_path2);
1778 free(new_path1);
1779 }
1780
1781 return ret;
1782 }
1783
1784 /*
1785 * Get the diff_filepairs changed between o_tree and tree.
1786 */
1787 static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
1788 struct tree *o_tree,
1789 struct tree *tree)
1790 {
1791 struct diff_queue_struct *ret;
1792 struct diff_options opts;
1793
1794 diff_setup(&opts);
1795 opts.flags.recursive = 1;
1796 opts.flags.rename_empty = 0;
1797 opts.detect_rename = merge_detect_rename(o);
1798 /*
1799 * We do not have logic to handle the detection of copies. In
1800 * fact, it may not even make sense to add such logic: would we
1801 * really want a change to a base file to be propagated through
1802 * multiple other files by a merge?
1803 */
1804 if (opts.detect_rename > DIFF_DETECT_RENAME)
1805 opts.detect_rename = DIFF_DETECT_RENAME;
1806 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
1807 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
1808 1000;
1809 opts.rename_score = o->rename_score;
1810 opts.show_rename_progress = o->show_rename_progress;
1811 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1812 diff_setup_done(&opts);
1813 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1814 diffcore_std(&opts);
1815 if (opts.needed_rename_limit > o->needed_rename_limit)
1816 o->needed_rename_limit = opts.needed_rename_limit;
1817
1818 ret = xmalloc(sizeof(*ret));
1819 *ret = diff_queued_diff;
1820
1821 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1822 diff_queued_diff.nr = 0;
1823 diff_queued_diff.queue = NULL;
1824 diff_flush(&opts);
1825 return ret;
1826 }
1827
1828 static int tree_has_path(struct tree *tree, const char *path)
1829 {
1830 struct object_id hashy;
1831 unsigned int mode_o;
1832
1833 return !get_tree_entry(&tree->object.oid, path,
1834 &hashy, &mode_o);
1835 }
1836
1837 /*
1838 * Return a new string that replaces the beginning portion (which matches
1839 * entry->dir), with entry->new_dir. In perl-speak:
1840 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1841 * NOTE:
1842 * Caller must ensure that old_path starts with entry->dir + '/'.
1843 */
1844 static char *apply_dir_rename(struct dir_rename_entry *entry,
1845 const char *old_path)
1846 {
1847 struct strbuf new_path = STRBUF_INIT;
1848 int oldlen, newlen;
1849
1850 if (entry->non_unique_new_dir)
1851 return NULL;
1852
1853 oldlen = strlen(entry->dir);
1854 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1855 strbuf_grow(&new_path, newlen);
1856 strbuf_addbuf(&new_path, &entry->new_dir);
1857 strbuf_addstr(&new_path, &old_path[oldlen]);
1858
1859 return strbuf_detach(&new_path, NULL);
1860 }
1861
1862 static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1863 char **old_dir, char **new_dir)
1864 {
1865 char *end_of_old, *end_of_new;
1866 int old_len, new_len;
1867
1868 *old_dir = NULL;
1869 *new_dir = NULL;
1870
1871 /*
1872 * For
1873 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1874 * the "e/foo.c" part is the same, we just want to know that
1875 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1876 * so, for this example, this function returns "a/b/c/d" in
1877 * *old_dir and "a/b/some/thing/else" in *new_dir.
1878 *
1879 * Also, if the basename of the file changed, we don't care. We
1880 * want to know which portion of the directory, if any, changed.
1881 */
1882 end_of_old = strrchr(old_path, '/');
1883 end_of_new = strrchr(new_path, '/');
1884
1885 if (end_of_old == NULL || end_of_new == NULL)
1886 return;
1887 while (*--end_of_new == *--end_of_old &&
1888 end_of_old != old_path &&
1889 end_of_new != new_path)
1890 ; /* Do nothing; all in the while loop */
1891 /*
1892 * We've found the first non-matching character in the directory
1893 * paths. That means the current directory we were comparing
1894 * represents the rename. Move end_of_old and end_of_new back
1895 * to the full directory name.
1896 */
1897 if (*end_of_old == '/')
1898 end_of_old++;
1899 if (*end_of_old != '/')
1900 end_of_new++;
1901 end_of_old = strchr(end_of_old, '/');
1902 end_of_new = strchr(end_of_new, '/');
1903
1904 /*
1905 * It may have been the case that old_path and new_path were the same
1906 * directory all along. Don't claim a rename if they're the same.
1907 */
1908 old_len = end_of_old - old_path;
1909 new_len = end_of_new - new_path;
1910
1911 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
1912 *old_dir = xstrndup(old_path, old_len);
1913 *new_dir = xstrndup(new_path, new_len);
1914 }
1915 }
1916
1917 static void remove_hashmap_entries(struct hashmap *dir_renames,
1918 struct string_list *items_to_remove)
1919 {
1920 int i;
1921 struct dir_rename_entry *entry;
1922
1923 for (i = 0; i < items_to_remove->nr; i++) {
1924 entry = items_to_remove->items[i].util;
1925 hashmap_remove(dir_renames, entry, NULL);
1926 }
1927 string_list_clear(items_to_remove, 0);
1928 }
1929
1930 /*
1931 * See if there is a directory rename for path, and if there are any file
1932 * level conflicts for the renamed location. If there is a rename and
1933 * there are no conflicts, return the new name. Otherwise, return NULL.
1934 */
1935 static char *handle_path_level_conflicts(struct merge_options *o,
1936 const char *path,
1937 struct dir_rename_entry *entry,
1938 struct hashmap *collisions,
1939 struct tree *tree)
1940 {
1941 char *new_path = NULL;
1942 struct collision_entry *collision_ent;
1943 int clean = 1;
1944 struct strbuf collision_paths = STRBUF_INIT;
1945
1946 /*
1947 * entry has the mapping of old directory name to new directory name
1948 * that we want to apply to path.
1949 */
1950 new_path = apply_dir_rename(entry, path);
1951
1952 if (!new_path) {
1953 /* This should only happen when entry->non_unique_new_dir set */
1954 if (!entry->non_unique_new_dir)
1955 BUG("entry->non_unqiue_dir not set and !new_path");
1956 output(o, 1, _("CONFLICT (directory rename split): "
1957 "Unclear where to place %s because directory "
1958 "%s was renamed to multiple other directories, "
1959 "with no destination getting a majority of the "
1960 "files."),
1961 path, entry->dir);
1962 clean = 0;
1963 return NULL;
1964 }
1965
1966 /*
1967 * The caller needs to have ensured that it has pre-populated
1968 * collisions with all paths that map to new_path. Do a quick check
1969 * to ensure that's the case.
1970 */
1971 collision_ent = collision_find_entry(collisions, new_path);
1972 if (collision_ent == NULL)
1973 BUG("collision_ent is NULL");
1974
1975 /*
1976 * Check for one-sided add/add/.../add conflicts, i.e.
1977 * where implicit renames from the other side doing
1978 * directory rename(s) can affect this side of history
1979 * to put multiple paths into the same location. Warn
1980 * and bail on directory renames for such paths.
1981 */
1982 if (collision_ent->reported_already) {
1983 clean = 0;
1984 } else if (tree_has_path(tree, new_path)) {
1985 collision_ent->reported_already = 1;
1986 strbuf_add_separated_string_list(&collision_paths, ", ",
1987 &collision_ent->source_files);
1988 output(o, 1, _("CONFLICT (implicit dir rename): Existing "
1989 "file/dir at %s in the way of implicit "
1990 "directory rename(s) putting the following "
1991 "path(s) there: %s."),
1992 new_path, collision_paths.buf);
1993 clean = 0;
1994 } else if (collision_ent->source_files.nr > 1) {
1995 collision_ent->reported_already = 1;
1996 strbuf_add_separated_string_list(&collision_paths, ", ",
1997 &collision_ent->source_files);
1998 output(o, 1, _("CONFLICT (implicit dir rename): Cannot map "
1999 "more than one path to %s; implicit directory "
2000 "renames tried to put these paths there: %s"),
2001 new_path, collision_paths.buf);
2002 clean = 0;
2003 }
2004
2005 /* Free memory we no longer need */
2006 strbuf_release(&collision_paths);
2007 if (!clean && new_path) {
2008 free(new_path);
2009 return NULL;
2010 }
2011
2012 return new_path;
2013 }
2014
2015 /*
2016 * There are a couple things we want to do at the directory level:
2017 * 1. Check for both sides renaming to the same thing, in order to avoid
2018 * implicit renaming of files that should be left in place. (See
2019 * testcase 6b in t6043 for details.)
2020 * 2. Prune directory renames if there are still files left in the
2021 * the original directory. These represent a partial directory rename,
2022 * i.e. a rename where only some of the files within the directory
2023 * were renamed elsewhere. (Technically, this could be done earlier
2024 * in get_directory_renames(), except that would prevent us from
2025 * doing the previous check and thus failing testcase 6b.)
2026 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
2027 * In the future, we could potentially record this info as well and
2028 * omit reporting rename/rename(1to2) conflicts for each path within
2029 * the affected directories, thus cleaning up the merge output.
2030 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
2031 * directory level, because merging directories is fine. If it
2032 * causes conflicts for files within those merged directories, then
2033 * that should be detected at the individual path level.
2034 */
2035 static void handle_directory_level_conflicts(struct merge_options *o,
2036 struct hashmap *dir_re_head,
2037 struct tree *head,
2038 struct hashmap *dir_re_merge,
2039 struct tree *merge)
2040 {
2041 struct hashmap_iter iter;
2042 struct dir_rename_entry *head_ent;
2043 struct dir_rename_entry *merge_ent;
2044
2045 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
2046 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
2047
2048 hashmap_iter_init(dir_re_head, &iter);
2049 while ((head_ent = hashmap_iter_next(&iter))) {
2050 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
2051 if (merge_ent &&
2052 !head_ent->non_unique_new_dir &&
2053 !merge_ent->non_unique_new_dir &&
2054 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
2055 /* 1. Renamed identically; remove it from both sides */
2056 string_list_append(&remove_from_head,
2057 head_ent->dir)->util = head_ent;
2058 strbuf_release(&head_ent->new_dir);
2059 string_list_append(&remove_from_merge,
2060 merge_ent->dir)->util = merge_ent;
2061 strbuf_release(&merge_ent->new_dir);
2062 } else if (tree_has_path(head, head_ent->dir)) {
2063 /* 2. This wasn't a directory rename after all */
2064 string_list_append(&remove_from_head,
2065 head_ent->dir)->util = head_ent;
2066 strbuf_release(&head_ent->new_dir);
2067 }
2068 }
2069
2070 remove_hashmap_entries(dir_re_head, &remove_from_head);
2071 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2072
2073 hashmap_iter_init(dir_re_merge, &iter);
2074 while ((merge_ent = hashmap_iter_next(&iter))) {
2075 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
2076 if (tree_has_path(merge, merge_ent->dir)) {
2077 /* 2. This wasn't a directory rename after all */
2078 string_list_append(&remove_from_merge,
2079 merge_ent->dir)->util = merge_ent;
2080 } else if (head_ent &&
2081 !head_ent->non_unique_new_dir &&
2082 !merge_ent->non_unique_new_dir) {
2083 /* 3. rename/rename(1to2) */
2084 /*
2085 * We can assume it's not rename/rename(1to1) because
2086 * that was case (1), already checked above. So we
2087 * know that head_ent->new_dir and merge_ent->new_dir
2088 * are different strings.
2089 */
2090 output(o, 1, _("CONFLICT (rename/rename): "
2091 "Rename directory %s->%s in %s. "
2092 "Rename directory %s->%s in %s"),
2093 head_ent->dir, head_ent->new_dir.buf, o->branch1,
2094 head_ent->dir, merge_ent->new_dir.buf, o->branch2);
2095 string_list_append(&remove_from_head,
2096 head_ent->dir)->util = head_ent;
2097 strbuf_release(&head_ent->new_dir);
2098 string_list_append(&remove_from_merge,
2099 merge_ent->dir)->util = merge_ent;
2100 strbuf_release(&merge_ent->new_dir);
2101 }
2102 }
2103
2104 remove_hashmap_entries(dir_re_head, &remove_from_head);
2105 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2106 }
2107
2108 static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
2109 struct tree *tree)
2110 {
2111 struct hashmap *dir_renames;
2112 struct hashmap_iter iter;
2113 struct dir_rename_entry *entry;
2114 int i;
2115
2116 /*
2117 * Typically, we think of a directory rename as all files from a
2118 * certain directory being moved to a target directory. However,
2119 * what if someone first moved two files from the original
2120 * directory in one commit, and then renamed the directory
2121 * somewhere else in a later commit? At merge time, we just know
2122 * that files from the original directory went to two different
2123 * places, and that the bulk of them ended up in the same place.
2124 * We want each directory rename to represent where the bulk of the
2125 * files from that directory end up; this function exists to find
2126 * where the bulk of the files went.
2127 *
2128 * The first loop below simply iterates through the list of file
2129 * renames, finding out how often each directory rename pair
2130 * possibility occurs.
2131 */
2132 dir_renames = xmalloc(sizeof(*dir_renames));
2133 dir_rename_init(dir_renames);
2134 for (i = 0; i < pairs->nr; ++i) {
2135 struct string_list_item *item;
2136 int *count;
2137 struct diff_filepair *pair = pairs->queue[i];
2138 char *old_dir, *new_dir;
2139
2140 /* File not part of directory rename if it wasn't renamed */
2141 if (pair->status != 'R')
2142 continue;
2143
2144 get_renamed_dir_portion(pair->one->path, pair->two->path,
2145 &old_dir, &new_dir);
2146 if (!old_dir)
2147 /* Directory didn't change at all; ignore this one. */
2148 continue;
2149
2150 entry = dir_rename_find_entry(dir_renames, old_dir);
2151 if (!entry) {
2152 entry = xmalloc(sizeof(*entry));
2153 dir_rename_entry_init(entry, old_dir);
2154 hashmap_put(dir_renames, entry);
2155 } else {
2156 free(old_dir);
2157 }
2158 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
2159 if (!item) {
2160 item = string_list_insert(&entry->possible_new_dirs,
2161 new_dir);
2162 item->util = xcalloc(1, sizeof(int));
2163 } else {
2164 free(new_dir);
2165 }
2166 count = item->util;
2167 *count += 1;
2168 }
2169
2170 /*
2171 * For each directory with files moved out of it, we find out which
2172 * target directory received the most files so we can declare it to
2173 * be the "winning" target location for the directory rename. This
2174 * winner gets recorded in new_dir. If there is no winner
2175 * (multiple target directories received the same number of files),
2176 * we set non_unique_new_dir. Once we've determined the winner (or
2177 * that there is no winner), we no longer need possible_new_dirs.
2178 */
2179 hashmap_iter_init(dir_renames, &iter);
2180 while ((entry = hashmap_iter_next(&iter))) {
2181 int max = 0;
2182 int bad_max = 0;
2183 char *best = NULL;
2184
2185 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
2186 int *count = entry->possible_new_dirs.items[i].util;
2187
2188 if (*count == max)
2189 bad_max = max;
2190 else if (*count > max) {
2191 max = *count;
2192 best = entry->possible_new_dirs.items[i].string;
2193 }
2194 }
2195 if (bad_max == max)
2196 entry->non_unique_new_dir = 1;
2197 else {
2198 assert(entry->new_dir.len == 0);
2199 strbuf_addstr(&entry->new_dir, best);
2200 }
2201 /*
2202 * The relevant directory sub-portion of the original full
2203 * filepaths were xstrndup'ed before inserting into
2204 * possible_new_dirs, and instead of manually iterating the
2205 * list and free'ing each, just lie and tell
2206 * possible_new_dirs that it did the strdup'ing so that it
2207 * will free them for us.
2208 */
2209 entry->possible_new_dirs.strdup_strings = 1;
2210 string_list_clear(&entry->possible_new_dirs, 1);
2211 }
2212
2213 return dir_renames;
2214 }
2215
2216 static struct dir_rename_entry *check_dir_renamed(const char *path,
2217 struct hashmap *dir_renames)
2218 {
2219 char *temp = xstrdup(path);
2220 char *end;
2221 struct dir_rename_entry *entry = NULL;;
2222
2223 while ((end = strrchr(temp, '/'))) {
2224 *end = '\0';
2225 entry = dir_rename_find_entry(dir_renames, temp);
2226 if (entry)
2227 break;
2228 }
2229 free(temp);
2230 return entry;
2231 }
2232
2233 static void compute_collisions(struct hashmap *collisions,
2234 struct hashmap *dir_renames,
2235 struct diff_queue_struct *pairs)
2236 {
2237 int i;
2238
2239 /*
2240 * Multiple files can be mapped to the same path due to directory
2241 * renames done by the other side of history. Since that other
2242 * side of history could have merged multiple directories into one,
2243 * if our side of history added the same file basename to each of
2244 * those directories, then all N of them would get implicitly
2245 * renamed by the directory rename detection into the same path,
2246 * and we'd get an add/add/.../add conflict, and all those adds
2247 * from *this* side of history. This is not representable in the
2248 * index, and users aren't going to easily be able to make sense of
2249 * it. So we need to provide a good warning about what's
2250 * happening, and fall back to no-directory-rename detection
2251 * behavior for those paths.
2252 *
2253 * See testcases 9e and all of section 5 from t6043 for examples.
2254 */
2255 collision_init(collisions);
2256
2257 for (i = 0; i < pairs->nr; ++i) {
2258 struct dir_rename_entry *dir_rename_ent;
2259 struct collision_entry *collision_ent;
2260 char *new_path;
2261 struct diff_filepair *pair = pairs->queue[i];
2262
2263 if (pair->status != 'A' && pair->status != 'R')
2264 continue;
2265 dir_rename_ent = check_dir_renamed(pair->two->path,
2266 dir_renames);
2267 if (!dir_rename_ent)
2268 continue;
2269
2270 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
2271 if (!new_path)
2272 /*
2273 * dir_rename_ent->non_unique_new_path is true, which
2274 * means there is no directory rename for us to use,
2275 * which means it won't cause us any additional
2276 * collisions.
2277 */
2278 continue;
2279 collision_ent = collision_find_entry(collisions, new_path);
2280 if (!collision_ent) {
2281 collision_ent = xcalloc(1,
2282 sizeof(struct collision_entry));
2283 hashmap_entry_init(collision_ent, strhash(new_path));
2284 hashmap_put(collisions, collision_ent);
2285 collision_ent->target_file = new_path;
2286 } else {
2287 free(new_path);
2288 }
2289 string_list_insert(&collision_ent->source_files,
2290 pair->two->path);
2291 }
2292 }
2293
2294 static char *check_for_directory_rename(struct merge_options *o,
2295 const char *path,
2296 struct tree *tree,
2297 struct hashmap *dir_renames,
2298 struct hashmap *dir_rename_exclusions,
2299 struct hashmap *collisions,
2300 int *clean_merge)
2301 {
2302 char *new_path = NULL;
2303 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
2304 struct dir_rename_entry *oentry = NULL;
2305
2306 if (!entry)
2307 return new_path;
2308
2309 /*
2310 * This next part is a little weird. We do not want to do an
2311 * implicit rename into a directory we renamed on our side, because
2312 * that will result in a spurious rename/rename(1to2) conflict. An
2313 * example:
2314 * Base commit: dumbdir/afile, otherdir/bfile
2315 * Side 1: smrtdir/afile, otherdir/bfile
2316 * Side 2: dumbdir/afile, dumbdir/bfile
2317 * Here, while working on Side 1, we could notice that otherdir was
2318 * renamed/merged to dumbdir, and change the diff_filepair for
2319 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
2320 * 2 will notice the rename from dumbdir to smrtdir, and do the
2321 * transitive rename to move it from dumbdir/bfile to
2322 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
2323 * smrtdir, a rename/rename(1to2) conflict. We really just want
2324 * the file to end up in smrtdir. And the way to achieve that is
2325 * to not let Side1 do the rename to dumbdir, since we know that is
2326 * the source of one of our directory renames.
2327 *
2328 * That's why oentry and dir_rename_exclusions is here.
2329 *
2330 * As it turns out, this also prevents N-way transient rename
2331 * confusion; See testcases 9c and 9d of t6043.
2332 */
2333 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
2334 if (oentry) {
2335 output(o, 1, _("WARNING: Avoiding applying %s -> %s rename "
2336 "to %s, because %s itself was renamed."),
2337 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
2338 } else {
2339 new_path = handle_path_level_conflicts(o, path, entry,
2340 collisions, tree);
2341 *clean_merge &= (new_path != NULL);
2342 }
2343
2344 return new_path;
2345 }
2346
2347 static void apply_directory_rename_modifications(struct merge_options *o,
2348 struct diff_filepair *pair,
2349 char *new_path,
2350 struct rename *re,
2351 struct tree *tree,
2352 struct tree *o_tree,
2353 struct tree *a_tree,
2354 struct tree *b_tree,
2355 struct string_list *entries,
2356 int *clean)
2357 {
2358 struct string_list_item *item;
2359 int stage = (tree == a_tree ? 2 : 3);
2360 int update_wd;
2361
2362 /*
2363 * In all cases where we can do directory rename detection,
2364 * unpack_trees() will have read pair->two->path into the
2365 * index and the working copy. We need to remove it so that
2366 * we can instead place it at new_path. It is guaranteed to
2367 * not be untracked (unpack_trees() would have errored out
2368 * saying the file would have been overwritten), but it might
2369 * be dirty, though.
2370 */
2371 update_wd = !was_dirty(o, pair->two->path);
2372 if (!update_wd)
2373 output(o, 1, _("Refusing to lose dirty file at %s"),
2374 pair->two->path);
2375 remove_file(o, 1, pair->two->path, !update_wd);
2376
2377 /* Find or create a new re->dst_entry */
2378 item = string_list_lookup(entries, new_path);
2379 if (item) {
2380 /*
2381 * Since we're renaming on this side of history, and it's
2382 * due to a directory rename on the other side of history
2383 * (which we only allow when the directory in question no
2384 * longer exists on the other side of history), the
2385 * original entry for re->dst_entry is no longer
2386 * necessary...
2387 */
2388 re->dst_entry->processed = 1;
2389
2390 /*
2391 * ...because we'll be using this new one.
2392 */
2393 re->dst_entry = item->util;
2394 } else {
2395 /*
2396 * re->dst_entry is for the before-dir-rename path, and we
2397 * need it to hold information for the after-dir-rename
2398 * path. Before creating a new entry, we need to mark the
2399 * old one as unnecessary (...unless it is shared by
2400 * src_entry, i.e. this didn't use to be a rename, in which
2401 * case we can just allow the normal processing to happen
2402 * for it).
2403 */
2404 if (pair->status == 'R')
2405 re->dst_entry->processed = 1;
2406
2407 re->dst_entry = insert_stage_data(new_path,
2408 o_tree, a_tree, b_tree,
2409 entries);
2410 item = string_list_insert(entries, new_path);
2411 item->util = re->dst_entry;
2412 }
2413
2414 /*
2415 * Update the stage_data with the information about the path we are
2416 * moving into place. That slot will be empty and available for us
2417 * to write to because of the collision checks in
2418 * handle_path_level_conflicts(). In other words,
2419 * re->dst_entry->stages[stage].oid will be the null_oid, so it's
2420 * open for us to write to.
2421 *
2422 * It may be tempting to actually update the index at this point as
2423 * well, using update_stages_for_stage_data(), but as per the big
2424 * "NOTE" in update_stages(), doing so will modify the current
2425 * in-memory index which will break calls to would_lose_untracked()
2426 * that we need to make. Instead, we need to just make sure that
2427 * the various conflict_rename_*() functions update the index
2428 * explicitly rather than relying on unpack_trees() to have done it.
2429 */
2430 get_tree_entry(&tree->object.oid,
2431 pair->two->path,
2432 &re->dst_entry->stages[stage].oid,
2433 &re->dst_entry->stages[stage].mode);
2434
2435 /* Update pair status */
2436 if (pair->status == 'A') {
2437 /*
2438 * Recording rename information for this add makes it look
2439 * like a rename/delete conflict. Make sure we can
2440 * correctly handle this as an add that was moved to a new
2441 * directory instead of reporting a rename/delete conflict.
2442 */
2443 re->add_turned_into_rename = 1;
2444 }
2445 /*
2446 * We don't actually look at pair->status again, but it seems
2447 * pedagogically correct to adjust it.
2448 */
2449 pair->status = 'R';
2450
2451 /*
2452 * Finally, record the new location.
2453 */
2454 pair->two->path = new_path;
2455 }
2456
2457 /*
2458 * Get information of all renames which occurred in 'pairs', making use of
2459 * any implicit directory renames inferred from the other side of history.
2460 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
2461 * to be able to associate the correct cache entries with the rename
2462 * information; tree is always equal to either a_tree or b_tree.
2463 */
2464 static struct string_list *get_renames(struct merge_options *o,
2465 struct diff_queue_struct *pairs,
2466 struct hashmap *dir_renames,
2467 struct hashmap *dir_rename_exclusions,
2468 struct tree *tree,
2469 struct tree *o_tree,
2470 struct tree *a_tree,
2471 struct tree *b_tree,
2472 struct string_list *entries,
2473 int *clean_merge)
2474 {
2475 int i;
2476 struct hashmap collisions;
2477 struct hashmap_iter iter;
2478 struct collision_entry *e;
2479 struct string_list *renames;
2480
2481 compute_collisions(&collisions, dir_renames, pairs);
2482 renames = xcalloc(1, sizeof(struct string_list));
2483
2484 for (i = 0; i < pairs->nr; ++i) {
2485 struct string_list_item *item;
2486 struct rename *re;
2487 struct diff_filepair *pair = pairs->queue[i];
2488 char *new_path; /* non-NULL only with directory renames */
2489
2490 if (pair->status != 'A' && pair->status != 'R') {
2491 diff_free_filepair(pair);
2492 continue;
2493 }
2494 new_path = check_for_directory_rename(o, pair->two->path, tree,
2495 dir_renames,
2496 dir_rename_exclusions,
2497 &collisions,
2498 clean_merge);
2499 if (pair->status != 'R' && !new_path) {
2500 diff_free_filepair(pair);
2501 continue;
2502 }
2503
2504 re = xmalloc(sizeof(*re));
2505 re->processed = 0;
2506 re->add_turned_into_rename = 0;
2507 re->pair = pair;
2508 item = string_list_lookup(entries, re->pair->one->path);
2509 if (!item)
2510 re->src_entry = insert_stage_data(re->pair->one->path,
2511 o_tree, a_tree, b_tree, entries);
2512 else
2513 re->src_entry = item->util;
2514
2515 item = string_list_lookup(entries, re->pair->two->path);
2516 if (!item)
2517 re->dst_entry = insert_stage_data(re->pair->two->path,
2518 o_tree, a_tree, b_tree, entries);
2519 else
2520 re->dst_entry = item->util;
2521 item = string_list_insert(renames, pair->one->path);
2522 item->util = re;
2523 if (new_path)
2524 apply_directory_rename_modifications(o, pair, new_path,
2525 re, tree, o_tree,
2526 a_tree, b_tree,
2527 entries,
2528 clean_merge);
2529 }
2530
2531 hashmap_iter_init(&collisions, &iter);
2532 while ((e = hashmap_iter_next(&iter))) {
2533 free(e->target_file);
2534 string_list_clear(&e->source_files, 0);
2535 }
2536 hashmap_free(&collisions, 1);
2537 return renames;
2538 }
2539
2540 static int process_renames(struct merge_options *o,
2541 struct string_list *a_renames,
2542 struct string_list *b_renames)
2543 {
2544 int clean_merge = 1, i, j;
2545 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2546 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2547 const struct rename *sre;
2548
2549 for (i = 0; i < a_renames->nr; i++) {
2550 sre = a_renames->items[i].util;
2551 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2552 = (void *)sre;
2553 }
2554 for (i = 0; i < b_renames->nr; i++) {
2555 sre = b_renames->items[i].util;
2556 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2557 = (void *)sre;
2558 }
2559
2560 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2561 struct string_list *renames1, *renames2Dst;
2562 struct rename *ren1 = NULL, *ren2 = NULL;
2563 const char *branch1, *branch2;
2564 const char *ren1_src, *ren1_dst;
2565 struct string_list_item *lookup;
2566
2567 if (i >= a_renames->nr) {
2568 ren2 = b_renames->items[j++].util;
2569 } else if (j >= b_renames->nr) {
2570 ren1 = a_renames->items[i++].util;
2571 } else {
2572 int compare = strcmp(a_renames->items[i].string,
2573 b_renames->items[j].string);
2574 if (compare <= 0)
2575 ren1 = a_renames->items[i++].util;
2576 if (compare >= 0)
2577 ren2 = b_renames->items[j++].util;
2578 }
2579
2580 /* TODO: refactor, so that 1/2 are not needed */
2581 if (ren1) {
2582 renames1 = a_renames;
2583 renames2Dst = &b_by_dst;
2584 branch1 = o->branch1;
2585 branch2 = o->branch2;
2586 } else {
2587 renames1 = b_renames;
2588 renames2Dst = &a_by_dst;
2589 branch1 = o->branch2;
2590 branch2 = o->branch1;
2591 SWAP(ren2, ren1);
2592 }
2593
2594 if (ren1->processed)
2595 continue;
2596 ren1->processed = 1;
2597 ren1->dst_entry->processed = 1;
2598 /* BUG: We should only mark src_entry as processed if we
2599 * are not dealing with a rename + add-source case.
2600 */
2601 ren1->src_entry->processed = 1;
2602
2603 ren1_src = ren1->pair->one->path;
2604 ren1_dst = ren1->pair->two->path;
2605
2606 if (ren2) {
2607 /* One file renamed on both sides */
2608 const char *ren2_src = ren2->pair->one->path;
2609 const char *ren2_dst = ren2->pair->two->path;
2610 enum rename_type rename_type;
2611 if (strcmp(ren1_src, ren2_src) != 0)
2612 BUG("ren1_src != ren2_src");
2613 ren2->dst_entry->processed = 1;
2614 ren2->processed = 1;
2615 if (strcmp(ren1_dst, ren2_dst) != 0) {
2616 rename_type = RENAME_ONE_FILE_TO_TWO;
2617 clean_merge = 0;
2618 } else {
2619 rename_type = RENAME_ONE_FILE_TO_ONE;
2620 /* BUG: We should only remove ren1_src in
2621 * the base stage (think of rename +
2622 * add-source cases).
2623 */
2624 remove_file(o, 1, ren1_src, 1);
2625 update_entry(ren1->dst_entry,
2626 ren1->pair->one,
2627 ren1->pair->two,
2628 ren2->pair->two);
2629 }
2630 setup_rename_conflict_info(rename_type,
2631 ren1->pair,
2632 ren2->pair,
2633 branch1,
2634 branch2,
2635 ren1->dst_entry,
2636 ren2->dst_entry,
2637 o,
2638 NULL,
2639 NULL);
2640 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2641 /* Two different files renamed to the same thing */
2642 char *ren2_dst;
2643 ren2 = lookup->util;
2644 ren2_dst = ren2->pair->two->path;
2645 if (strcmp(ren1_dst, ren2_dst) != 0)
2646 BUG("ren1_dst != ren2_dst");
2647
2648 clean_merge = 0;
2649 ren2->processed = 1;
2650 /*
2651 * BUG: We should only mark src_entry as processed
2652 * if we are not dealing with a rename + add-source
2653 * case.
2654 */
2655 ren2->src_entry->processed = 1;
2656
2657 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2658 ren1->pair,
2659 ren2->pair,
2660 branch1,
2661 branch2,
2662 ren1->dst_entry,
2663 ren2->dst_entry,
2664 o,
2665 ren1->src_entry,
2666 ren2->src_entry);
2667
2668 } else {
2669 /* Renamed in 1, maybe changed in 2 */
2670 /* we only use sha1 and mode of these */
2671 struct diff_filespec src_other, dst_other;
2672 int try_merge;
2673
2674 /*
2675 * unpack_trees loads entries from common-commit
2676 * into stage 1, from head-commit into stage 2, and
2677 * from merge-commit into stage 3. We keep track
2678 * of which side corresponds to the rename.
2679 */
2680 int renamed_stage = a_renames == renames1 ? 2 : 3;
2681 int other_stage = a_renames == renames1 ? 3 : 2;
2682
2683 /* BUG: We should only remove ren1_src in the base
2684 * stage and in other_stage (think of rename +
2685 * add-source case).
2686 */
2687 remove_file(o, 1, ren1_src,
2688 renamed_stage == 2 || !was_tracked(o, ren1_src));
2689
2690 oidcpy(&src_other.oid,
2691 &ren1->src_entry->stages[other_stage].oid);
2692 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2693 oidcpy(&dst_other.oid,
2694 &ren1->dst_entry->stages[other_stage].oid);
2695 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2696 try_merge = 0;
2697
2698 if (oid_eq(&src_other.oid, &null_oid) &&
2699 ren1->add_turned_into_rename) {
2700 setup_rename_conflict_info(RENAME_DIR,
2701 ren1->pair,
2702 NULL,
2703 branch1,
2704 branch2,
2705 ren1->dst_entry,
2706 NULL,
2707 o,
2708 NULL,
2709 NULL);
2710 } else if (oid_eq(&src_other.oid, &null_oid)) {
2711 setup_rename_conflict_info(RENAME_DELETE,
2712 ren1->pair,
2713 NULL,
2714 branch1,
2715 branch2,
2716 ren1->dst_entry,
2717 NULL,
2718 o,
2719 NULL,
2720 NULL);
2721 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2722 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2723 /*
2724 * Added file on the other side identical to
2725 * the file being renamed: clean merge.
2726 * Also, there is no need to overwrite the
2727 * file already in the working copy, so call
2728 * update_file_flags() instead of
2729 * update_file().
2730 */
2731 if (update_file_flags(o,
2732 &ren1->pair->two->oid,
2733 ren1->pair->two->mode,
2734 ren1_dst,
2735 1, /* update_cache */
2736 0 /* update_wd */))
2737 clean_merge = -1;
2738 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2739 clean_merge = 0;
2740 try_merge = 1;
2741 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
2742 "%s added in %s"),
2743 ren1_src, ren1_dst, branch1,
2744 ren1_dst, branch2);
2745 if (o->call_depth) {
2746 struct merge_file_info mfi;
2747 if (merge_file_one(o, ren1_dst, &null_oid, 0,
2748 &ren1->pair->two->oid,
2749 ren1->pair->two->mode,
2750 &dst_other.oid,
2751 dst_other.mode,
2752 branch1, branch2, &mfi)) {
2753 clean_merge = -1;
2754 goto cleanup_and_return;
2755 }
2756 output(o, 1, _("Adding merged %s"), ren1_dst);
2757 if (update_file(o, 0, &mfi.oid,
2758 mfi.mode, ren1_dst))
2759 clean_merge = -1;
2760 try_merge = 0;
2761 } else {
2762 char *new_path = unique_path(o, ren1_dst, branch2);
2763 output(o, 1, _("Adding as %s instead"), new_path);
2764 if (update_file(o, 0, &dst_other.oid,
2765 dst_other.mode, new_path))
2766 clean_merge = -1;
2767 free(new_path);
2768 }
2769 } else
2770 try_merge = 1;
2771
2772 if (clean_merge < 0)
2773 goto cleanup_and_return;
2774 if (try_merge) {
2775 struct diff_filespec *one, *a, *b;
2776 src_other.path = (char *)ren1_src;
2777
2778 one = ren1->pair->one;
2779 if (a_renames == renames1) {
2780 a = ren1->pair->two;
2781 b = &src_other;
2782 } else {
2783 b = ren1->pair->two;
2784 a = &src_other;
2785 }
2786 update_entry(ren1->dst_entry, one, a, b);
2787 setup_rename_conflict_info(RENAME_NORMAL,
2788 ren1->pair,
2789 NULL,
2790 branch1,
2791 NULL,
2792 ren1->dst_entry,
2793 NULL,
2794 o,
2795 NULL,
2796 NULL);
2797 }
2798 }
2799 }
2800 cleanup_and_return:
2801 string_list_clear(&a_by_dst, 0);
2802 string_list_clear(&b_by_dst, 0);
2803
2804 return clean_merge;
2805 }
2806
2807 struct rename_info {
2808 struct string_list *head_renames;
2809 struct string_list *merge_renames;
2810 };
2811
2812 static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2813 struct hashmap *dir_renames)
2814 {
2815 struct hashmap_iter iter;
2816 struct dir_rename_entry *e;
2817
2818 hashmap_iter_init(dir_renames, &iter);
2819 while ((e = hashmap_iter_next(&iter))) {
2820 free(e->dir);
2821 strbuf_release(&e->new_dir);
2822 /* possible_new_dirs already cleared in get_directory_renames */
2823 }
2824 hashmap_free(dir_renames, 1);
2825 free(dir_renames);
2826
2827 free(pairs->queue);
2828 free(pairs);
2829 }
2830
2831 static int handle_renames(struct merge_options *o,
2832 struct tree *common,
2833 struct tree *head,
2834 struct tree *merge,
2835 struct string_list *entries,
2836 struct rename_info *ri)
2837 {
2838 struct diff_queue_struct *head_pairs, *merge_pairs;
2839 struct hashmap *dir_re_head, *dir_re_merge;
2840 int clean = 1;
2841
2842 ri->head_renames = NULL;
2843 ri->merge_renames = NULL;
2844
2845 if (!merge_detect_rename(o))
2846 return 1;
2847
2848 head_pairs = get_diffpairs(o, common, head);
2849 merge_pairs = get_diffpairs(o, common, merge);
2850
2851 dir_re_head = get_directory_renames(head_pairs, head);
2852 dir_re_merge = get_directory_renames(merge_pairs, merge);
2853
2854 handle_directory_level_conflicts(o,
2855 dir_re_head, head,
2856 dir_re_merge, merge);
2857
2858 ri->head_renames = get_renames(o, head_pairs,
2859 dir_re_merge, dir_re_head, head,
2860 common, head, merge, entries,
2861 &clean);
2862 if (clean < 0)
2863 goto cleanup;
2864 ri->merge_renames = get_renames(o, merge_pairs,
2865 dir_re_head, dir_re_merge, merge,
2866 common, head, merge, entries,
2867 &clean);
2868 if (clean < 0)
2869 goto cleanup;
2870 clean &= process_renames(o, ri->head_renames, ri->merge_renames);
2871
2872 cleanup:
2873 /*
2874 * Some cleanup is deferred until cleanup_renames() because the
2875 * data structures are still needed and referenced in
2876 * process_entry(). But there are a few things we can free now.
2877 */
2878 initial_cleanup_rename(head_pairs, dir_re_head);
2879 initial_cleanup_rename(merge_pairs, dir_re_merge);
2880
2881 return clean;
2882 }
2883
2884 static void final_cleanup_rename(struct string_list *rename)
2885 {
2886 const struct rename *re;
2887 int i;
2888
2889 if (rename == NULL)
2890 return;
2891
2892 for (i = 0; i < rename->nr; i++) {
2893 re = rename->items[i].util;
2894 diff_free_filepair(re->pair);
2895 }
2896 string_list_clear(rename, 1);
2897 free(rename);
2898 }
2899
2900 static void final_cleanup_renames(struct rename_info *re_info)
2901 {
2902 final_cleanup_rename(re_info->head_renames);
2903 final_cleanup_rename(re_info->merge_renames);
2904 }
2905
2906 static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
2907 {
2908 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
2909 }
2910
2911 static int read_oid_strbuf(struct merge_options *o,
2912 const struct object_id *oid, struct strbuf *dst)
2913 {
2914 void *buf;
2915 enum object_type type;
2916 unsigned long size;
2917 buf = read_object_file(oid, &type, &size);
2918 if (!buf)
2919 return err(o, _("cannot read object %s"), oid_to_hex(oid));
2920 if (type != OBJ_BLOB) {
2921 free(buf);
2922 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
2923 }
2924 strbuf_attach(dst, buf, size, size + 1);
2925 return 0;
2926 }
2927
2928 static int blob_unchanged(struct merge_options *opt,
2929 const struct object_id *o_oid,
2930 unsigned o_mode,
2931 const struct object_id *a_oid,
2932 unsigned a_mode,
2933 int renormalize, const char *path)
2934 {
2935 struct strbuf o = STRBUF_INIT;
2936 struct strbuf a = STRBUF_INIT;
2937 int ret = 0; /* assume changed for safety */
2938
2939 if (a_mode != o_mode)
2940 return 0;
2941 if (oid_eq(o_oid, a_oid))
2942 return 1;
2943 if (!renormalize)
2944 return 0;
2945
2946 assert(o_oid && a_oid);
2947 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
2948 goto error_return;
2949 /*
2950 * Note: binary | is used so that both renormalizations are
2951 * performed. Comparison can be skipped if both files are
2952 * unchanged since their sha1s have already been compared.
2953 */
2954 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
2955 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
2956 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
2957
2958 error_return:
2959 strbuf_release(&o);
2960 strbuf_release(&a);
2961 return ret;
2962 }
2963
2964 static int handle_modify_delete(struct merge_options *o,
2965 const char *path,
2966 struct object_id *o_oid, int o_mode,
2967 struct object_id *a_oid, int a_mode,
2968 struct object_id *b_oid, int b_mode)
2969 {
2970 const char *modify_branch, *delete_branch;
2971 struct object_id *changed_oid;
2972 int changed_mode;
2973
2974 if (a_oid) {
2975 modify_branch = o->branch1;
2976 delete_branch = o->branch2;
2977 changed_oid = a_oid;
2978 changed_mode = a_mode;
2979 } else {
2980 modify_branch = o->branch2;
2981 delete_branch = o->branch1;
2982 changed_oid = b_oid;
2983 changed_mode = b_mode;
2984 }
2985
2986 return handle_change_delete(o,
2987 path, NULL,
2988 o_oid, o_mode,
2989 changed_oid, changed_mode,
2990 modify_branch, delete_branch,
2991 _("modify"), _("modified"));
2992 }
2993
2994 static int merge_content(struct merge_options *o,
2995 const char *path,
2996 int is_dirty,
2997 struct object_id *o_oid, int o_mode,
2998 struct object_id *a_oid, int a_mode,
2999 struct object_id *b_oid, int b_mode,
3000 struct rename_conflict_info *rename_conflict_info)
3001 {
3002 const char *reason = _("content");
3003 const char *path1 = NULL, *path2 = NULL;
3004 struct merge_file_info mfi;
3005 struct diff_filespec one, a, b;
3006 unsigned df_conflict_remains = 0;
3007
3008 if (!o_oid) {
3009 reason = _("add/add");
3010 o_oid = (struct object_id *)&null_oid;
3011 }
3012 one.path = a.path = b.path = (char *)path;
3013 oidcpy(&one.oid, o_oid);
3014 one.mode = o_mode;
3015 oidcpy(&a.oid, a_oid);
3016 a.mode = a_mode;
3017 oidcpy(&b.oid, b_oid);
3018 b.mode = b_mode;
3019
3020 if (rename_conflict_info) {
3021 struct diff_filepair *pair1 = rename_conflict_info->pair1;
3022
3023 path1 = (o->branch1 == rename_conflict_info->branch1) ?
3024 pair1->two->path : pair1->one->path;
3025 /* If rename_conflict_info->pair2 != NULL, we are in
3026 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
3027 * normal rename.
3028 */
3029 path2 = (rename_conflict_info->pair2 ||
3030 o->branch2 == rename_conflict_info->branch1) ?
3031 pair1->two->path : pair1->one->path;
3032
3033 if (dir_in_way(path, !o->call_depth,
3034 S_ISGITLINK(pair1->two->mode)))
3035 df_conflict_remains = 1;
3036 }
3037 if (merge_file_special_markers(o, &one, &a, &b, path,
3038 o->branch1, path1,
3039 o->branch2, path2, &mfi))
3040 return -1;
3041
3042 /*
3043 * We can skip updating the working tree file iff:
3044 * a) The merge is clean
3045 * b) The merge matches what was in HEAD (content, mode, pathname)
3046 * c) The target path is usable (i.e. not involved in D/F conflict)
3047 */
3048 if (mfi.clean &&
3049 was_tracked_and_matches(o, path, &mfi.oid, mfi.mode) &&
3050 !df_conflict_remains) {
3051 output(o, 3, _("Skipped %s (merged same as existing)"), path);
3052 if (add_cacheinfo(o, mfi.mode, &mfi.oid, path,
3053 0, (!o->call_depth && !is_dirty), 0))
3054 return -1;
3055 return mfi.clean;
3056 }
3057
3058 if (!mfi.clean) {
3059 if (S_ISGITLINK(mfi.mode))
3060 reason = _("submodule");
3061 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
3062 reason, path);
3063 if (rename_conflict_info && !df_conflict_remains)
3064 if (update_stages(o, path, &one, &a, &b))
3065 return -1;
3066 }
3067
3068 if (df_conflict_remains || is_dirty) {
3069 char *new_path;
3070 if (o->call_depth) {
3071 remove_file_from_cache(path);
3072 } else {
3073 if (!mfi.clean) {
3074 if (update_stages(o, path, &one, &a, &b))
3075 return -1;
3076 } else {
3077 int file_from_stage2 = was_tracked(o, path);
3078 struct diff_filespec merged;
3079 oidcpy(&merged.oid, &mfi.oid);
3080 merged.mode = mfi.mode;
3081
3082 if (update_stages(o, path, NULL,
3083 file_from_stage2 ? &merged : NULL,
3084 file_from_stage2 ? NULL : &merged))
3085 return -1;
3086 }
3087
3088 }
3089 new_path = unique_path(o, path, rename_conflict_info->branch1);
3090 if (is_dirty) {
3091 output(o, 1, _("Refusing to lose dirty file at %s"),
3092 path);
3093 }
3094 output(o, 1, _("Adding as %s instead"), new_path);
3095 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
3096 free(new_path);
3097 return -1;
3098 }
3099 free(new_path);
3100 mfi.clean = 0;
3101 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
3102 return -1;
3103 return !is_dirty && mfi.clean;
3104 }
3105
3106 static int conflict_rename_normal(struct merge_options *o,
3107 const char *path,
3108 struct object_id *o_oid, unsigned int o_mode,
3109 struct object_id *a_oid, unsigned int a_mode,
3110 struct object_id *b_oid, unsigned int b_mode,
3111 struct rename_conflict_info *ci)
3112 {
3113 /* Merge the content and write it out */
3114 return merge_content(o, path, was_dirty(o, path),
3115 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3116 ci);
3117 }
3118
3119 /* Per entry merge function */
3120 static int process_entry(struct merge_options *o,
3121 const char *path, struct stage_data *entry)
3122 {
3123 int clean_merge = 1;
3124 int normalize = o->renormalize;
3125 unsigned o_mode = entry->stages[1].mode;
3126 unsigned a_mode = entry->stages[2].mode;
3127 unsigned b_mode = entry->stages[3].mode;
3128 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
3129 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
3130 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
3131
3132 entry->processed = 1;
3133 if (entry->rename_conflict_info) {
3134 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
3135 switch (conflict_info->rename_type) {
3136 case RENAME_NORMAL:
3137 case RENAME_ONE_FILE_TO_ONE:
3138 clean_merge = conflict_rename_normal(o,
3139 path,
3140 o_oid, o_mode,
3141 a_oid, a_mode,
3142 b_oid, b_mode,
3143 conflict_info);
3144 break;
3145 case RENAME_DIR:
3146 clean_merge = 1;
3147 if (conflict_rename_dir(o,
3148 conflict_info->pair1,
3149 conflict_info->branch1,
3150 conflict_info->branch2))
3151 clean_merge = -1;
3152 break;
3153 case RENAME_DELETE:
3154 clean_merge = 0;
3155 if (conflict_rename_delete(o,
3156 conflict_info->pair1,
3157 conflict_info->branch1,
3158 conflict_info->branch2))
3159 clean_merge = -1;
3160 break;
3161 case RENAME_ONE_FILE_TO_TWO:
3162 clean_merge = 0;
3163 if (conflict_rename_rename_1to2(o, conflict_info))
3164 clean_merge = -1;
3165 break;
3166 case RENAME_TWO_FILES_TO_ONE:
3167 clean_merge = 0;
3168 if (conflict_rename_rename_2to1(o, conflict_info))
3169 clean_merge = -1;
3170 break;
3171 default:
3172 entry->processed = 0;
3173 break;
3174 }
3175 } else if (o_oid && (!a_oid || !b_oid)) {
3176 /* Case A: Deleted in one */
3177 if ((!a_oid && !b_oid) ||
3178 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
3179 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
3180 /* Deleted in both or deleted in one and
3181 * unchanged in the other */
3182 if (a_oid)
3183 output(o, 2, _("Removing %s"), path);
3184 /* do not touch working file if it did not exist */
3185 remove_file(o, 1, path, !a_oid);
3186 } else {
3187 /* Modify/delete; deleted side may have put a directory in the way */
3188 clean_merge = 0;
3189 if (handle_modify_delete(o, path, o_oid, o_mode,
3190 a_oid, a_mode, b_oid, b_mode))
3191 clean_merge = -1;
3192 }
3193 } else if ((!o_oid && a_oid && !b_oid) ||
3194 (!o_oid && !a_oid && b_oid)) {
3195 /* Case B: Added in one. */
3196 /* [nothing|directory] -> ([nothing|directory], file) */
3197
3198 const char *add_branch;
3199 const char *other_branch;
3200 unsigned mode;
3201 const struct object_id *oid;
3202 const char *conf;
3203
3204 if (a_oid) {
3205 add_branch = o->branch1;
3206 other_branch = o->branch2;
3207 mode = a_mode;
3208 oid = a_oid;
3209 conf = _("file/directory");
3210 } else {
3211 add_branch = o->branch2;
3212 other_branch = o->branch1;
3213 mode = b_mode;
3214 oid = b_oid;
3215 conf = _("directory/file");
3216 }
3217 if (dir_in_way(path,
3218 !o->call_depth && !S_ISGITLINK(a_mode),
3219 0)) {
3220 char *new_path = unique_path(o, path, add_branch);
3221 clean_merge = 0;
3222 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
3223 "Adding %s as %s"),
3224 conf, path, other_branch, path, new_path);
3225 if (update_file(o, 0, oid, mode, new_path))
3226 clean_merge = -1;
3227 else if (o->call_depth)
3228 remove_file_from_cache(path);
3229 free(new_path);
3230 } else {
3231 output(o, 2, _("Adding %s"), path);
3232 /* do not overwrite file if already present */
3233 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
3234 clean_merge = -1;
3235 }
3236 } else if (a_oid && b_oid) {
3237 /* Case C: Added in both (check for same permissions) and */
3238 /* case D: Modified in both, but differently. */
3239 int is_dirty = 0; /* unpack_trees would have bailed if dirty */
3240 clean_merge = merge_content(o, path, is_dirty,
3241 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3242 NULL);
3243 } else if (!o_oid && !a_oid && !b_oid) {
3244 /*
3245 * this entry was deleted altogether. a_mode == 0 means
3246 * we had that path and want to actively remove it.
3247 */
3248 remove_file(o, 1, path, !a_mode);
3249 } else
3250 BUG("fatal merge failure, shouldn't happen.");
3251
3252 return clean_merge;
3253 }
3254
3255 int merge_trees(struct merge_options *o,
3256 struct tree *head,
3257 struct tree *merge,
3258 struct tree *common,
3259 struct tree **result)
3260 {
3261 int code, clean;
3262
3263 if (o->subtree_shift) {
3264 merge = shift_tree_object(head, merge, o->subtree_shift);
3265 common = shift_tree_object(head, common, o->subtree_shift);
3266 }
3267
3268 if (oid_eq(&common->object.oid, &merge->object.oid)) {
3269 struct strbuf sb = STRBUF_INIT;
3270
3271 if (!o->call_depth && index_has_changes(&sb)) {
3272 err(o, _("Dirty index: cannot merge (dirty: %s)"),
3273 sb.buf);
3274 return 0;
3275 }
3276 output(o, 0, _("Already up to date!"));
3277 *result = head;
3278 return 1;
3279 }
3280
3281 code = unpack_trees_start(o, common, head, merge);
3282
3283 if (code != 0) {
3284 if (show(o, 4) || o->call_depth)
3285 err(o, _("merging of trees %s and %s failed"),
3286 oid_to_hex(&head->object.oid),
3287 oid_to_hex(&merge->object.oid));
3288 unpack_trees_finish(o);
3289 return -1;
3290 }
3291
3292 if (unmerged_cache()) {
3293 struct string_list *entries;
3294 struct rename_info re_info;
3295 int i;
3296 /*
3297 * Only need the hashmap while processing entries, so
3298 * initialize it here and free it when we are done running
3299 * through the entries. Keeping it in the merge_options as
3300 * opposed to decaring a local hashmap is for convenience
3301 * so that we don't have to pass it to around.
3302 */
3303 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
3304 get_files_dirs(o, head);
3305 get_files_dirs(o, merge);
3306
3307 entries = get_unmerged();
3308 clean = handle_renames(o, common, head, merge, entries,
3309 &re_info);
3310 record_df_conflict_files(o, entries);
3311 if (clean < 0)
3312 goto cleanup;
3313 for (i = entries->nr-1; 0 <= i; i--) {
3314 const char *path = entries->items[i].string;
3315 struct stage_data *e = entries->items[i].util;
3316 if (!e->processed) {
3317 int ret = process_entry(o, path, e);
3318 if (!ret)
3319 clean = 0;
3320 else if (ret < 0) {
3321 clean = ret;
3322 goto cleanup;
3323 }
3324 }
3325 }
3326 for (i = 0; i < entries->nr; i++) {
3327 struct stage_data *e = entries->items[i].util;
3328 if (!e->processed)
3329 BUG("unprocessed path??? %s",
3330 entries->items[i].string);
3331 }
3332
3333 cleanup:
3334 final_cleanup_renames(&re_info);
3335
3336 string_list_clear(entries, 1);
3337 free(entries);
3338
3339 hashmap_free(&o->current_file_dir_set, 1);
3340
3341 if (clean < 0) {
3342 unpack_trees_finish(o);
3343 return clean;
3344 }
3345 }
3346 else
3347 clean = 1;
3348
3349 unpack_trees_finish(o);
3350
3351 if (o->call_depth && !(*result = write_tree_from_memory(o)))
3352 return -1;
3353
3354 return clean;
3355 }
3356
3357 static struct commit_list *reverse_commit_list(struct commit_list *list)
3358 {
3359 struct commit_list *next = NULL, *current, *backup;
3360 for (current = list; current; current = backup) {
3361 backup = current->next;
3362 current->next = next;
3363 next = current;
3364 }
3365 return next;
3366 }
3367
3368 /*
3369 * Merge the commits h1 and h2, return the resulting virtual
3370 * commit object and a flag indicating the cleanness of the merge.
3371 */
3372 int merge_recursive(struct merge_options *o,
3373 struct commit *h1,
3374 struct commit *h2,
3375 struct commit_list *ca,
3376 struct commit **result)
3377 {
3378 struct commit_list *iter;
3379 struct commit *merged_common_ancestors;
3380 struct tree *mrtree;
3381 int clean;
3382
3383 if (show(o, 4)) {
3384 output(o, 4, _("Merging:"));
3385 output_commit_title(o, h1);
3386 output_commit_title(o, h2);
3387 }
3388
3389 if (!ca) {
3390 ca = get_merge_bases(h1, h2);
3391 ca = reverse_commit_list(ca);
3392 }
3393
3394 if (show(o, 5)) {
3395 unsigned cnt = commit_list_count(ca);
3396
3397 output(o, 5, Q_("found %u common ancestor:",
3398 "found %u common ancestors:", cnt), cnt);
3399 for (iter = ca; iter; iter = iter->next)
3400 output_commit_title(o, iter->item);
3401 }
3402
3403 merged_common_ancestors = pop_commit(&ca);
3404 if (merged_common_ancestors == NULL) {
3405 /* if there is no common ancestor, use an empty tree */
3406 struct tree *tree;
3407
3408 tree = lookup_tree(the_repository, the_repository->hash_algo->empty_tree);
3409 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
3410 }
3411
3412 for (iter = ca; iter; iter = iter->next) {
3413 const char *saved_b1, *saved_b2;
3414 o->call_depth++;
3415 /*
3416 * When the merge fails, the result contains files
3417 * with conflict markers. The cleanness flag is
3418 * ignored (unless indicating an error), it was never
3419 * actually used, as result of merge_trees has always
3420 * overwritten it: the committed "conflicts" were
3421 * already resolved.
3422 */
3423 discard_cache();
3424 saved_b1 = o->branch1;
3425 saved_b2 = o->branch2;
3426 o->branch1 = "Temporary merge branch 1";
3427 o->branch2 = "Temporary merge branch 2";
3428 if (merge_recursive(o, merged_common_ancestors, iter->item,
3429 NULL, &merged_common_ancestors) < 0)
3430 return -1;
3431 o->branch1 = saved_b1;
3432 o->branch2 = saved_b2;
3433 o->call_depth--;
3434
3435 if (!merged_common_ancestors)
3436 return err(o, _("merge returned no commit"));
3437 }
3438
3439 discard_cache();
3440 if (!o->call_depth)
3441 read_cache();
3442
3443 o->ancestor = "merged common ancestors";
3444 clean = merge_trees(o, get_commit_tree(h1), get_commit_tree(h2),
3445 get_commit_tree(merged_common_ancestors),
3446 &mrtree);
3447 if (clean < 0) {
3448 flush_output(o);
3449 return clean;
3450 }
3451
3452 if (o->call_depth) {
3453 *result = make_virtual_commit(mrtree, "merged tree");
3454 commit_list_insert(h1, &(*result)->parents);
3455 commit_list_insert(h2, &(*result)->parents->next);
3456 }
3457 flush_output(o);
3458 if (!o->call_depth && o->buffer_output < 2)
3459 strbuf_release(&o->obuf);
3460 if (show(o, 2))
3461 diff_warn_rename_limit("merge.renamelimit",
3462 o->needed_rename_limit, 0);
3463 return clean;
3464 }
3465
3466 static struct commit *get_ref(const struct object_id *oid, const char *name)
3467 {
3468 struct object *object;
3469
3470 object = deref_tag(parse_object(the_repository, oid), name,
3471 strlen(name));
3472 if (!object)
3473 return NULL;
3474 if (object->type == OBJ_TREE)
3475 return make_virtual_commit((struct tree*)object, name);
3476 if (object->type != OBJ_COMMIT)
3477 return NULL;
3478 if (parse_commit((struct commit *)object))
3479 return NULL;
3480 return (struct commit *)object;
3481 }
3482
3483 int merge_recursive_generic(struct merge_options *o,
3484 const struct object_id *head,
3485 const struct object_id *merge,
3486 int num_base_list,
3487 const struct object_id **base_list,
3488 struct commit **result)
3489 {
3490 int clean;
3491 struct lock_file lock = LOCK_INIT;
3492 struct commit *head_commit = get_ref(head, o->branch1);
3493 struct commit *next_commit = get_ref(merge, o->branch2);
3494 struct commit_list *ca = NULL;
3495
3496 if (base_list) {
3497 int i;
3498 for (i = 0; i < num_base_list; ++i) {
3499 struct commit *base;
3500 if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i]))))
3501 return err(o, _("Could not parse object '%s'"),
3502 oid_to_hex(base_list[i]));
3503 commit_list_insert(base, &ca);
3504 }
3505 }
3506
3507 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
3508 clean = merge_recursive(o, head_commit, next_commit, ca,
3509 result);
3510 if (clean < 0) {
3511 rollback_lock_file(&lock);
3512 return clean;
3513 }
3514
3515 if (write_locked_index(&the_index, &lock,
3516 COMMIT_LOCK | SKIP_IF_UNCHANGED))
3517 return err(o, _("Unable to write index."));
3518
3519 return clean ? 0 : 1;
3520 }
3521
3522 static void merge_recursive_config(struct merge_options *o)
3523 {
3524 char *value = NULL;
3525 git_config_get_int("merge.verbosity", &o->verbosity);
3526 git_config_get_int("diff.renamelimit", &o->diff_rename_limit);
3527 git_config_get_int("merge.renamelimit", &o->merge_rename_limit);
3528 if (!git_config_get_string("diff.renames", &value)) {
3529 o->diff_detect_rename = git_config_rename("diff.renames", value);
3530 free(value);
3531 }
3532 if (!git_config_get_string("merge.renames", &value)) {
3533 o->merge_detect_rename = git_config_rename("merge.renames", value);
3534 free(value);
3535 }
3536 git_config(git_xmerge_config, NULL);
3537 }
3538
3539 void init_merge_options(struct merge_options *o)
3540 {
3541 const char *merge_verbosity;
3542 memset(o, 0, sizeof(struct merge_options));
3543 o->verbosity = 2;
3544 o->buffer_output = 1;
3545 o->diff_rename_limit = -1;
3546 o->merge_rename_limit = -1;
3547 o->renormalize = 0;
3548 o->diff_detect_rename = -1;
3549 o->merge_detect_rename = -1;
3550 merge_recursive_config(o);
3551 merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
3552 if (merge_verbosity)
3553 o->verbosity = strtol(merge_verbosity, NULL, 10);
3554 if (o->verbosity >= 5)
3555 o->buffer_output = 0;
3556 strbuf_init(&o->obuf, 0);
3557 string_list_init(&o->df_conflict_file_set, 1);
3558 }
3559
3560 int parse_merge_opt(struct merge_options *o, const char *s)
3561 {
3562 const char *arg;
3563
3564 if (!s || !*s)
3565 return -1;
3566 if (!strcmp(s, "ours"))
3567 o->recursive_variant = MERGE_RECURSIVE_OURS;
3568 else if (!strcmp(s, "theirs"))
3569 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
3570 else if (!strcmp(s, "subtree"))
3571 o->subtree_shift = "";
3572 else if (skip_prefix(s, "subtree=", &arg))
3573 o->subtree_shift = arg;
3574 else if (!strcmp(s, "patience"))
3575 o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF);
3576 else if (!strcmp(s, "histogram"))
3577 o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF);
3578 else if (skip_prefix(s, "diff-algorithm=", &arg)) {
3579 long value = parse_algorithm_value(arg);
3580 if (value < 0)
3581 return -1;
3582 /* clear out previous settings */
3583 DIFF_XDL_CLR(o, NEED_MINIMAL);
3584 o->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
3585 o->xdl_opts |= value;
3586 }
3587 else if (!strcmp(s, "ignore-space-change"))
3588 DIFF_XDL_SET(o, IGNORE_WHITESPACE_CHANGE);
3589 else if (!strcmp(s, "ignore-all-space"))
3590 DIFF_XDL_SET(o, IGNORE_WHITESPACE);
3591 else if (!strcmp(s, "ignore-space-at-eol"))
3592 DIFF_XDL_SET(o, IGNORE_WHITESPACE_AT_EOL);
3593 else if (!strcmp(s, "ignore-cr-at-eol"))
3594 DIFF_XDL_SET(o, IGNORE_CR_AT_EOL);
3595 else if (!strcmp(s, "renormalize"))
3596 o->renormalize = 1;
3597 else if (!strcmp(s, "no-renormalize"))
3598 o->renormalize = 0;
3599 else if (!strcmp(s, "no-renames"))
3600 o->merge_detect_rename = 0;
360