Merge branch 'en/directory-renames-nothanks'
[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_VIA_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(&the_index, mode, oid ? oid : &null_oid, 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(&the_index, 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 exists 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(&the_index, 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(the_repository, base)) ||
1196 !(commit_a = lookup_commit_reference(the_repository, a)) ||
1197 !(commit_b = lookup_commit_reference(the_repository, 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 handle_rename_via_dir(struct merge_options *o,
1419 struct diff_filepair *pair,
1420 const char *rename_branch,
1421 const char *other_branch)
1422 {
1423 /*
1424 * Handle file adds that need to be renamed due to directory rename
1425 * detection. This differs from handle_rename_normal, because
1426 * there is no content merge to do; just move the file into the
1427 * desired final location.
1428 */
1429 const struct diff_filespec *dest = pair->two;
1430
1431 if (!o->call_depth && would_lose_untracked(dest->path)) {
1432 char *alt_path = unique_path(o, dest->path, rename_branch);
1433
1434 output(o, 1, _("Error: Refusing to lose untracked file at %s; "
1435 "writing to %s instead."),
1436 dest->path, alt_path);
1437 /*
1438 * Write the file in worktree at alt_path, but not in the
1439 * index. Instead, write to dest->path for the index but
1440 * only at the higher appropriate stage.
1441 */
1442 if (update_file(o, 0, &dest->oid, dest->mode, alt_path))
1443 return -1;
1444 free(alt_path);
1445 return update_stages(o, dest->path, NULL,
1446 rename_branch == o->branch1 ? dest : NULL,
1447 rename_branch == o->branch1 ? NULL : dest);
1448 }
1449
1450 /* Update dest->path both in index and in worktree */
1451 if (update_file(o, 1, &dest->oid, dest->mode, dest->path))
1452 return -1;
1453 return 0;
1454 }
1455
1456 static int handle_change_delete(struct merge_options *o,
1457 const char *path, const char *old_path,
1458 const struct object_id *o_oid, int o_mode,
1459 const struct object_id *changed_oid,
1460 int changed_mode,
1461 const char *change_branch,
1462 const char *delete_branch,
1463 const char *change, const char *change_past)
1464 {
1465 char *alt_path = NULL;
1466 const char *update_path = path;
1467 int ret = 0;
1468
1469 if (dir_in_way(path, !o->call_depth, 0) ||
1470 (!o->call_depth && would_lose_untracked(path))) {
1471 update_path = alt_path = unique_path(o, path, change_branch);
1472 }
1473
1474 if (o->call_depth) {
1475 /*
1476 * We cannot arbitrarily accept either a_sha or b_sha as
1477 * correct; since there is no true "middle point" between
1478 * them, simply reuse the base version for virtual merge base.
1479 */
1480 ret = remove_file_from_cache(path);
1481 if (!ret)
1482 ret = update_file(o, 0, o_oid, o_mode, update_path);
1483 } else {
1484 /*
1485 * Despite the four nearly duplicate messages and argument
1486 * lists below and the ugliness of the nested if-statements,
1487 * having complete messages makes the job easier for
1488 * translators.
1489 *
1490 * The slight variance among the cases is due to the fact
1491 * that:
1492 * 1) directory/file conflicts (in effect if
1493 * !alt_path) could cause us to need to write the
1494 * file to a different path.
1495 * 2) renames (in effect if !old_path) could mean that
1496 * there are two names for the path that the user
1497 * may know the file by.
1498 */
1499 if (!alt_path) {
1500 if (!old_path) {
1501 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1502 "and %s in %s. Version %s of %s left in tree."),
1503 change, path, delete_branch, change_past,
1504 change_branch, change_branch, path);
1505 } else {
1506 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1507 "and %s to %s in %s. Version %s of %s left in tree."),
1508 change, old_path, delete_branch, change_past, path,
1509 change_branch, change_branch, path);
1510 }
1511 } else {
1512 if (!old_path) {
1513 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1514 "and %s in %s. Version %s of %s left in tree at %s."),
1515 change, path, delete_branch, change_past,
1516 change_branch, change_branch, path, alt_path);
1517 } else {
1518 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1519 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1520 change, old_path, delete_branch, change_past, path,
1521 change_branch, change_branch, path, alt_path);
1522 }
1523 }
1524 /*
1525 * No need to call update_file() on path when change_branch ==
1526 * o->branch1 && !alt_path, since that would needlessly touch
1527 * path. We could call update_file_flags() with update_cache=0
1528 * and update_wd=0, but that's a no-op.
1529 */
1530 if (change_branch != o->branch1 || alt_path)
1531 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1532 }
1533 free(alt_path);
1534
1535 return ret;
1536 }
1537
1538 static int handle_rename_delete(struct merge_options *o,
1539 struct diff_filepair *pair,
1540 const char *rename_branch,
1541 const char *delete_branch)
1542 {
1543 const struct diff_filespec *orig = pair->one;
1544 const struct diff_filespec *dest = pair->two;
1545
1546 if (handle_change_delete(o,
1547 o->call_depth ? orig->path : dest->path,
1548 o->call_depth ? NULL : orig->path,
1549 &orig->oid, orig->mode,
1550 &dest->oid, dest->mode,
1551 rename_branch, delete_branch,
1552 _("rename"), _("renamed")))
1553 return -1;
1554
1555 if (o->call_depth)
1556 return remove_file_from_cache(dest->path);
1557 else
1558 return update_stages(o, dest->path, NULL,
1559 rename_branch == o->branch1 ? dest : NULL,
1560 rename_branch == o->branch1 ? NULL : dest);
1561 }
1562
1563 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1564 struct stage_data *entry,
1565 int stage)
1566 {
1567 struct object_id *oid = &entry->stages[stage].oid;
1568 unsigned mode = entry->stages[stage].mode;
1569 if (mode == 0 || is_null_oid(oid))
1570 return NULL;
1571 oidcpy(&target->oid, oid);
1572 target->mode = mode;
1573 return target;
1574 }
1575
1576 static int handle_file(struct merge_options *o,
1577 struct diff_filespec *rename,
1578 int stage,
1579 struct rename_conflict_info *ci)
1580 {
1581 char *dst_name = rename->path;
1582 struct stage_data *dst_entry;
1583 const char *cur_branch, *other_branch;
1584 struct diff_filespec other;
1585 struct diff_filespec *add;
1586 int ret;
1587
1588 if (stage == 2) {
1589 dst_entry = ci->dst_entry1;
1590 cur_branch = ci->branch1;
1591 other_branch = ci->branch2;
1592 } else {
1593 dst_entry = ci->dst_entry2;
1594 cur_branch = ci->branch2;
1595 other_branch = ci->branch1;
1596 }
1597
1598 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1599 if (add) {
1600 int ren_src_was_dirty = was_dirty(o, rename->path);
1601 char *add_name = unique_path(o, rename->path, other_branch);
1602 if (update_file(o, 0, &add->oid, add->mode, add_name))
1603 return -1;
1604
1605 if (ren_src_was_dirty) {
1606 output(o, 1, _("Refusing to lose dirty file at %s"),
1607 rename->path);
1608 }
1609 /*
1610 * Because the double negatives somehow keep confusing me...
1611 * 1) update_wd iff !ren_src_was_dirty.
1612 * 2) no_wd iff !update_wd
1613 * 3) so, no_wd == !!ren_src_was_dirty == ren_src_was_dirty
1614 */
1615 remove_file(o, 0, rename->path, ren_src_was_dirty);
1616 dst_name = unique_path(o, rename->path, cur_branch);
1617 } else {
1618 if (dir_in_way(rename->path, !o->call_depth, 0)) {
1619 dst_name = unique_path(o, rename->path, cur_branch);
1620 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1621 rename->path, other_branch, dst_name);
1622 } else if (!o->call_depth &&
1623 would_lose_untracked(rename->path)) {
1624 dst_name = unique_path(o, rename->path, cur_branch);
1625 output(o, 1, _("Refusing to lose untracked file at %s; "
1626 "adding as %s instead"),
1627 rename->path, dst_name);
1628 }
1629 }
1630 if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name)))
1631 ; /* fall through, do allow dst_name to be released */
1632 else if (stage == 2)
1633 ret = update_stages(o, rename->path, NULL, rename, add);
1634 else
1635 ret = update_stages(o, rename->path, NULL, add, rename);
1636
1637 if (dst_name != rename->path)
1638 free(dst_name);
1639
1640 return ret;
1641 }
1642
1643 static int handle_rename_rename_1to2(struct merge_options *o,
1644 struct rename_conflict_info *ci)
1645 {
1646 /* One file was renamed in both branches, but to different names. */
1647 struct diff_filespec *one = ci->pair1->one;
1648 struct diff_filespec *a = ci->pair1->two;
1649 struct diff_filespec *b = ci->pair2->two;
1650
1651 output(o, 1, _("CONFLICT (rename/rename): "
1652 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1653 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1654 one->path, a->path, ci->branch1,
1655 one->path, b->path, ci->branch2,
1656 o->call_depth ? _(" (left unresolved)") : "");
1657 if (o->call_depth) {
1658 struct merge_file_info mfi;
1659 struct diff_filespec other;
1660 struct diff_filespec *add;
1661 if (merge_file_one(o, one->path,
1662 &one->oid, one->mode,
1663 &a->oid, a->mode,
1664 &b->oid, b->mode,
1665 ci->branch1, ci->branch2, &mfi))
1666 return -1;
1667
1668 /*
1669 * FIXME: For rename/add-source conflicts (if we could detect
1670 * such), this is wrong. We should instead find a unique
1671 * pathname and then either rename the add-source file to that
1672 * unique path, or use that unique path instead of src here.
1673 */
1674 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1675 return -1;
1676
1677 /*
1678 * Above, we put the merged content at the merge-base's
1679 * path. Now we usually need to delete both a->path and
1680 * b->path. However, the rename on each side of the merge
1681 * could also be involved in a rename/add conflict. In
1682 * such cases, we should keep the added file around,
1683 * resolving the conflict at that path in its favor.
1684 */
1685 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1686 if (add) {
1687 if (update_file(o, 0, &add->oid, add->mode, a->path))
1688 return -1;
1689 }
1690 else
1691 remove_file_from_cache(a->path);
1692 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1693 if (add) {
1694 if (update_file(o, 0, &add->oid, add->mode, b->path))
1695 return -1;
1696 }
1697 else
1698 remove_file_from_cache(b->path);
1699 } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci))
1700 return -1;
1701
1702 return 0;
1703 }
1704
1705 static int handle_rename_rename_2to1(struct merge_options *o,
1706 struct rename_conflict_info *ci)
1707 {
1708 /* Two files, a & b, were renamed to the same thing, c. */
1709 struct diff_filespec *a = ci->pair1->one;
1710 struct diff_filespec *b = ci->pair2->one;
1711 struct diff_filespec *c1 = ci->pair1->two;
1712 struct diff_filespec *c2 = ci->pair2->two;
1713 char *path = c1->path; /* == c2->path */
1714 char *path_side_1_desc;
1715 char *path_side_2_desc;
1716 struct merge_file_info mfi_c1;
1717 struct merge_file_info mfi_c2;
1718 int ret;
1719
1720 output(o, 1, _("CONFLICT (rename/rename): "
1721 "Rename %s->%s in %s. "
1722 "Rename %s->%s in %s"),
1723 a->path, c1->path, ci->branch1,
1724 b->path, c2->path, ci->branch2);
1725
1726 remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path));
1727 remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path));
1728
1729 path_side_1_desc = xstrfmt("%s (was %s)", path, a->path);
1730 path_side_2_desc = xstrfmt("%s (was %s)", path, b->path);
1731 if (merge_file_special_markers(o, a, c1, &ci->ren1_other,
1732 path_side_1_desc,
1733 o->branch1, c1->path,
1734 o->branch2, ci->ren1_other.path, &mfi_c1) ||
1735 merge_file_special_markers(o, b, &ci->ren2_other, c2,
1736 path_side_2_desc,
1737 o->branch1, ci->ren2_other.path,
1738 o->branch2, c2->path, &mfi_c2))
1739 return -1;
1740 free(path_side_1_desc);
1741 free(path_side_2_desc);
1742
1743 if (o->call_depth) {
1744 /*
1745 * If mfi_c1.clean && mfi_c2.clean, then it might make
1746 * sense to do a two-way merge of those results. But, I
1747 * think in all cases, it makes sense to have the virtual
1748 * merge base just undo the renames; they can be detected
1749 * again later for the non-recursive merge.
1750 */
1751 remove_file(o, 0, path, 0);
1752 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path);
1753 if (!ret)
1754 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1755 b->path);
1756 } else {
1757 char *new_path1 = unique_path(o, path, ci->branch1);
1758 char *new_path2 = unique_path(o, path, ci->branch2);
1759 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1760 a->path, new_path1, b->path, new_path2);
1761 if (was_dirty(o, path))
1762 output(o, 1, _("Refusing to lose dirty file at %s"),
1763 path);
1764 else if (would_lose_untracked(path))
1765 /*
1766 * Only way we get here is if both renames were from
1767 * a directory rename AND user had an untracked file
1768 * at the location where both files end up after the
1769 * two directory renames. See testcase 10d of t6043.
1770 */
1771 output(o, 1, _("Refusing to lose untracked file at "
1772 "%s, even though it's in the way."),
1773 path);
1774 else
1775 remove_file(o, 0, path, 0);
1776 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1);
1777 if (!ret)
1778 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1779 new_path2);
1780 /*
1781 * unpack_trees() actually populates the index for us for
1782 * "normal" rename/rename(2to1) situtations so that the
1783 * correct entries are at the higher stages, which would
1784 * make the call below to update_stages_for_stage_data
1785 * unnecessary. However, if either of the renames came
1786 * from a directory rename, then unpack_trees() will not
1787 * have gotten the right data loaded into the index, so we
1788 * need to do so now. (While it'd be tempting to move this
1789 * call to update_stages_for_stage_data() to
1790 * apply_directory_rename_modifications(), that would break
1791 * our intermediate calls to would_lose_untracked() since
1792 * those rely on the current in-memory index. See also the
1793 * big "NOTE" in update_stages()).
1794 */
1795 if (update_stages_for_stage_data(o, path, ci->dst_entry1))
1796 ret = -1;
1797
1798 free(new_path2);
1799 free(new_path1);
1800 }
1801
1802 return ret;
1803 }
1804
1805 /*
1806 * Get the diff_filepairs changed between o_tree and tree.
1807 */
1808 static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
1809 struct tree *o_tree,
1810 struct tree *tree)
1811 {
1812 struct diff_queue_struct *ret;
1813 struct diff_options opts;
1814
1815 diff_setup(&opts);
1816 opts.flags.recursive = 1;
1817 opts.flags.rename_empty = 0;
1818 opts.detect_rename = merge_detect_rename(o);
1819 /*
1820 * We do not have logic to handle the detection of copies. In
1821 * fact, it may not even make sense to add such logic: would we
1822 * really want a change to a base file to be propagated through
1823 * multiple other files by a merge?
1824 */
1825 if (opts.detect_rename > DIFF_DETECT_RENAME)
1826 opts.detect_rename = DIFF_DETECT_RENAME;
1827 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
1828 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
1829 1000;
1830 opts.rename_score = o->rename_score;
1831 opts.show_rename_progress = o->show_rename_progress;
1832 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1833 diff_setup_done(&opts);
1834 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1835 diffcore_std(&opts);
1836 if (opts.needed_rename_limit > o->needed_rename_limit)
1837 o->needed_rename_limit = opts.needed_rename_limit;
1838
1839 ret = xmalloc(sizeof(*ret));
1840 *ret = diff_queued_diff;
1841
1842 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1843 diff_queued_diff.nr = 0;
1844 diff_queued_diff.queue = NULL;
1845 diff_flush(&opts);
1846 return ret;
1847 }
1848
1849 static int tree_has_path(struct tree *tree, const char *path)
1850 {
1851 struct object_id hashy;
1852 unsigned int mode_o;
1853
1854 return !get_tree_entry(&tree->object.oid, path,
1855 &hashy, &mode_o);
1856 }
1857
1858 /*
1859 * Return a new string that replaces the beginning portion (which matches
1860 * entry->dir), with entry->new_dir. In perl-speak:
1861 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1862 * NOTE:
1863 * Caller must ensure that old_path starts with entry->dir + '/'.
1864 */
1865 static char *apply_dir_rename(struct dir_rename_entry *entry,
1866 const char *old_path)
1867 {
1868 struct strbuf new_path = STRBUF_INIT;
1869 int oldlen, newlen;
1870
1871 if (entry->non_unique_new_dir)
1872 return NULL;
1873
1874 oldlen = strlen(entry->dir);
1875 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1876 strbuf_grow(&new_path, newlen);
1877 strbuf_addbuf(&new_path, &entry->new_dir);
1878 strbuf_addstr(&new_path, &old_path[oldlen]);
1879
1880 return strbuf_detach(&new_path, NULL);
1881 }
1882
1883 static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1884 char **old_dir, char **new_dir)
1885 {
1886 char *end_of_old, *end_of_new;
1887 int old_len, new_len;
1888
1889 *old_dir = NULL;
1890 *new_dir = NULL;
1891
1892 /*
1893 * For
1894 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1895 * the "e/foo.c" part is the same, we just want to know that
1896 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1897 * so, for this example, this function returns "a/b/c/d" in
1898 * *old_dir and "a/b/some/thing/else" in *new_dir.
1899 *
1900 * Also, if the basename of the file changed, we don't care. We
1901 * want to know which portion of the directory, if any, changed.
1902 */
1903 end_of_old = strrchr(old_path, '/');
1904 end_of_new = strrchr(new_path, '/');
1905
1906 if (end_of_old == NULL || end_of_new == NULL)
1907 return;
1908 while (*--end_of_new == *--end_of_old &&
1909 end_of_old != old_path &&
1910 end_of_new != new_path)
1911 ; /* Do nothing; all in the while loop */
1912 /*
1913 * We've found the first non-matching character in the directory
1914 * paths. That means the current directory we were comparing
1915 * represents the rename. Move end_of_old and end_of_new back
1916 * to the full directory name.
1917 */
1918 if (*end_of_old == '/')
1919 end_of_old++;
1920 if (*end_of_old != '/')
1921 end_of_new++;
1922 end_of_old = strchr(end_of_old, '/');
1923 end_of_new = strchr(end_of_new, '/');
1924
1925 /*
1926 * It may have been the case that old_path and new_path were the same
1927 * directory all along. Don't claim a rename if they're the same.
1928 */
1929 old_len = end_of_old - old_path;
1930 new_len = end_of_new - new_path;
1931
1932 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
1933 *old_dir = xstrndup(old_path, old_len);
1934 *new_dir = xstrndup(new_path, new_len);
1935 }
1936 }
1937
1938 static void remove_hashmap_entries(struct hashmap *dir_renames,
1939 struct string_list *items_to_remove)
1940 {
1941 int i;
1942 struct dir_rename_entry *entry;
1943
1944 for (i = 0; i < items_to_remove->nr; i++) {
1945 entry = items_to_remove->items[i].util;
1946 hashmap_remove(dir_renames, entry, NULL);
1947 }
1948 string_list_clear(items_to_remove, 0);
1949 }
1950
1951 /*
1952 * See if there is a directory rename for path, and if there are any file
1953 * level conflicts for the renamed location. If there is a rename and
1954 * there are no conflicts, return the new name. Otherwise, return NULL.
1955 */
1956 static char *handle_path_level_conflicts(struct merge_options *o,
1957 const char *path,
1958 struct dir_rename_entry *entry,
1959 struct hashmap *collisions,
1960 struct tree *tree)
1961 {
1962 char *new_path = NULL;
1963 struct collision_entry *collision_ent;
1964 int clean = 1;
1965 struct strbuf collision_paths = STRBUF_INIT;
1966
1967 /*
1968 * entry has the mapping of old directory name to new directory name
1969 * that we want to apply to path.
1970 */
1971 new_path = apply_dir_rename(entry, path);
1972
1973 if (!new_path) {
1974 /* This should only happen when entry->non_unique_new_dir set */
1975 if (!entry->non_unique_new_dir)
1976 BUG("entry->non_unqiue_dir not set and !new_path");
1977 output(o, 1, _("CONFLICT (directory rename split): "
1978 "Unclear where to place %s because directory "
1979 "%s was renamed to multiple other directories, "
1980 "with no destination getting a majority of the "
1981 "files."),
1982 path, entry->dir);
1983 clean = 0;
1984 return NULL;
1985 }
1986
1987 /*
1988 * The caller needs to have ensured that it has pre-populated
1989 * collisions with all paths that map to new_path. Do a quick check
1990 * to ensure that's the case.
1991 */
1992 collision_ent = collision_find_entry(collisions, new_path);
1993 if (collision_ent == NULL)
1994 BUG("collision_ent is NULL");
1995
1996 /*
1997 * Check for one-sided add/add/.../add conflicts, i.e.
1998 * where implicit renames from the other side doing
1999 * directory rename(s) can affect this side of history
2000 * to put multiple paths into the same location. Warn
2001 * and bail on directory renames for such paths.
2002 */
2003 if (collision_ent->reported_already) {
2004 clean = 0;
2005 } else if (tree_has_path(tree, new_path)) {
2006 collision_ent->reported_already = 1;
2007 strbuf_add_separated_string_list(&collision_paths, ", ",
2008 &collision_ent->source_files);
2009 output(o, 1, _("CONFLICT (implicit dir rename): Existing "
2010 "file/dir at %s in the way of implicit "
2011 "directory rename(s) putting the following "
2012 "path(s) there: %s."),
2013 new_path, collision_paths.buf);
2014 clean = 0;
2015 } else if (collision_ent->source_files.nr > 1) {
2016 collision_ent->reported_already = 1;
2017 strbuf_add_separated_string_list(&collision_paths, ", ",
2018 &collision_ent->source_files);
2019 output(o, 1, _("CONFLICT (implicit dir rename): Cannot map "
2020 "more than one path to %s; implicit directory "
2021 "renames tried to put these paths there: %s"),
2022 new_path, collision_paths.buf);
2023 clean = 0;
2024 }
2025
2026 /* Free memory we no longer need */
2027 strbuf_release(&collision_paths);
2028 if (!clean && new_path) {
2029 free(new_path);
2030 return NULL;
2031 }
2032
2033 return new_path;
2034 }
2035
2036 /*
2037 * There are a couple things we want to do at the directory level:
2038 * 1. Check for both sides renaming to the same thing, in order to avoid
2039 * implicit renaming of files that should be left in place. (See
2040 * testcase 6b in t6043 for details.)
2041 * 2. Prune directory renames if there are still files left in the
2042 * the original directory. These represent a partial directory rename,
2043 * i.e. a rename where only some of the files within the directory
2044 * were renamed elsewhere. (Technically, this could be done earlier
2045 * in get_directory_renames(), except that would prevent us from
2046 * doing the previous check and thus failing testcase 6b.)
2047 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
2048 * In the future, we could potentially record this info as well and
2049 * omit reporting rename/rename(1to2) conflicts for each path within
2050 * the affected directories, thus cleaning up the merge output.
2051 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
2052 * directory level, because merging directories is fine. If it
2053 * causes conflicts for files within those merged directories, then
2054 * that should be detected at the individual path level.
2055 */
2056 static void handle_directory_level_conflicts(struct merge_options *o,
2057 struct hashmap *dir_re_head,
2058 struct tree *head,
2059 struct hashmap *dir_re_merge,
2060 struct tree *merge)
2061 {
2062 struct hashmap_iter iter;
2063 struct dir_rename_entry *head_ent;
2064 struct dir_rename_entry *merge_ent;
2065
2066 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
2067 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
2068
2069 hashmap_iter_init(dir_re_head, &iter);
2070 while ((head_ent = hashmap_iter_next(&iter))) {
2071 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
2072 if (merge_ent &&
2073 !head_ent->non_unique_new_dir &&
2074 !merge_ent->non_unique_new_dir &&
2075 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
2076 /* 1. Renamed identically; remove it from both sides */
2077 string_list_append(&remove_from_head,
2078 head_ent->dir)->util = head_ent;
2079 strbuf_release(&head_ent->new_dir);
2080 string_list_append(&remove_from_merge,
2081 merge_ent->dir)->util = merge_ent;
2082 strbuf_release(&merge_ent->new_dir);
2083 } else if (tree_has_path(head, head_ent->dir)) {
2084 /* 2. This wasn't a directory rename after all */
2085 string_list_append(&remove_from_head,
2086 head_ent->dir)->util = head_ent;
2087 strbuf_release(&head_ent->new_dir);
2088 }
2089 }
2090
2091 remove_hashmap_entries(dir_re_head, &remove_from_head);
2092 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2093
2094 hashmap_iter_init(dir_re_merge, &iter);
2095 while ((merge_ent = hashmap_iter_next(&iter))) {
2096 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
2097 if (tree_has_path(merge, merge_ent->dir)) {
2098 /* 2. This wasn't a directory rename after all */
2099 string_list_append(&remove_from_merge,
2100 merge_ent->dir)->util = merge_ent;
2101 } else if (head_ent &&
2102 !head_ent->non_unique_new_dir &&
2103 !merge_ent->non_unique_new_dir) {
2104 /* 3. rename/rename(1to2) */
2105 /*
2106 * We can assume it's not rename/rename(1to1) because
2107 * that was case (1), already checked above. So we
2108 * know that head_ent->new_dir and merge_ent->new_dir
2109 * are different strings.
2110 */
2111 output(o, 1, _("CONFLICT (rename/rename): "
2112 "Rename directory %s->%s in %s. "
2113 "Rename directory %s->%s in %s"),
2114 head_ent->dir, head_ent->new_dir.buf, o->branch1,
2115 head_ent->dir, merge_ent->new_dir.buf, o->branch2);
2116 string_list_append(&remove_from_head,
2117 head_ent->dir)->util = head_ent;
2118 strbuf_release(&head_ent->new_dir);
2119 string_list_append(&remove_from_merge,
2120 merge_ent->dir)->util = merge_ent;
2121 strbuf_release(&merge_ent->new_dir);
2122 }
2123 }
2124
2125 remove_hashmap_entries(dir_re_head, &remove_from_head);
2126 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2127 }
2128
2129 static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
2130 struct tree *tree)
2131 {
2132 struct hashmap *dir_renames;
2133 struct hashmap_iter iter;
2134 struct dir_rename_entry *entry;
2135 int i;
2136
2137 /*
2138 * Typically, we think of a directory rename as all files from a
2139 * certain directory being moved to a target directory. However,
2140 * what if someone first moved two files from the original
2141 * directory in one commit, and then renamed the directory
2142 * somewhere else in a later commit? At merge time, we just know
2143 * that files from the original directory went to two different
2144 * places, and that the bulk of them ended up in the same place.
2145 * We want each directory rename to represent where the bulk of the
2146 * files from that directory end up; this function exists to find
2147 * where the bulk of the files went.
2148 *
2149 * The first loop below simply iterates through the list of file
2150 * renames, finding out how often each directory rename pair
2151 * possibility occurs.
2152 */
2153 dir_renames = xmalloc(sizeof(*dir_renames));
2154 dir_rename_init(dir_renames);
2155 for (i = 0; i < pairs->nr; ++i) {
2156 struct string_list_item *item;
2157 int *count;
2158 struct diff_filepair *pair = pairs->queue[i];
2159 char *old_dir, *new_dir;
2160
2161 /* File not part of directory rename if it wasn't renamed */
2162 if (pair->status != 'R')
2163 continue;
2164
2165 get_renamed_dir_portion(pair->one->path, pair->two->path,
2166 &old_dir, &new_dir);
2167 if (!old_dir)
2168 /* Directory didn't change at all; ignore this one. */
2169 continue;
2170
2171 entry = dir_rename_find_entry(dir_renames, old_dir);
2172 if (!entry) {
2173 entry = xmalloc(sizeof(*entry));
2174 dir_rename_entry_init(entry, old_dir);
2175 hashmap_put(dir_renames, entry);
2176 } else {
2177 free(old_dir);
2178 }
2179 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
2180 if (!item) {
2181 item = string_list_insert(&entry->possible_new_dirs,
2182 new_dir);
2183 item->util = xcalloc(1, sizeof(int));
2184 } else {
2185 free(new_dir);
2186 }
2187 count = item->util;
2188 *count += 1;
2189 }
2190
2191 /*
2192 * For each directory with files moved out of it, we find out which
2193 * target directory received the most files so we can declare it to
2194 * be the "winning" target location for the directory rename. This
2195 * winner gets recorded in new_dir. If there is no winner
2196 * (multiple target directories received the same number of files),
2197 * we set non_unique_new_dir. Once we've determined the winner (or
2198 * that there is no winner), we no longer need possible_new_dirs.
2199 */
2200 hashmap_iter_init(dir_renames, &iter);
2201 while ((entry = hashmap_iter_next(&iter))) {
2202 int max = 0;
2203 int bad_max = 0;
2204 char *best = NULL;
2205
2206 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
2207 int *count = entry->possible_new_dirs.items[i].util;
2208
2209 if (*count == max)
2210 bad_max = max;
2211 else if (*count > max) {
2212 max = *count;
2213 best = entry->possible_new_dirs.items[i].string;
2214 }
2215 }
2216 if (bad_max == max)
2217 entry->non_unique_new_dir = 1;
2218 else {
2219 assert(entry->new_dir.len == 0);
2220 strbuf_addstr(&entry->new_dir, best);
2221 }
2222 /*
2223 * The relevant directory sub-portion of the original full
2224 * filepaths were xstrndup'ed before inserting into
2225 * possible_new_dirs, and instead of manually iterating the
2226 * list and free'ing each, just lie and tell
2227 * possible_new_dirs that it did the strdup'ing so that it
2228 * will free them for us.
2229 */
2230 entry->possible_new_dirs.strdup_strings = 1;
2231 string_list_clear(&entry->possible_new_dirs, 1);
2232 }
2233
2234 return dir_renames;
2235 }
2236
2237 static struct dir_rename_entry *check_dir_renamed(const char *path,
2238 struct hashmap *dir_renames)
2239 {
2240 char *temp = xstrdup(path);
2241 char *end;
2242 struct dir_rename_entry *entry = NULL;;
2243
2244 while ((end = strrchr(temp, '/'))) {
2245 *end = '\0';
2246 entry = dir_rename_find_entry(dir_renames, temp);
2247 if (entry)
2248 break;
2249 }
2250 free(temp);
2251 return entry;
2252 }
2253
2254 static void compute_collisions(struct hashmap *collisions,
2255 struct hashmap *dir_renames,
2256 struct diff_queue_struct *pairs)
2257 {
2258 int i;
2259
2260 /*
2261 * Multiple files can be mapped to the same path due to directory
2262 * renames done by the other side of history. Since that other
2263 * side of history could have merged multiple directories into one,
2264 * if our side of history added the same file basename to each of
2265 * those directories, then all N of them would get implicitly
2266 * renamed by the directory rename detection into the same path,
2267 * and we'd get an add/add/.../add conflict, and all those adds
2268 * from *this* side of history. This is not representable in the
2269 * index, and users aren't going to easily be able to make sense of
2270 * it. So we need to provide a good warning about what's
2271 * happening, and fall back to no-directory-rename detection
2272 * behavior for those paths.
2273 *
2274 * See testcases 9e and all of section 5 from t6043 for examples.
2275 */
2276 collision_init(collisions);
2277
2278 for (i = 0; i < pairs->nr; ++i) {
2279 struct dir_rename_entry *dir_rename_ent;
2280 struct collision_entry *collision_ent;
2281 char *new_path;
2282 struct diff_filepair *pair = pairs->queue[i];
2283
2284 if (pair->status != 'A' && pair->status != 'R')
2285 continue;
2286 dir_rename_ent = check_dir_renamed(pair->two->path,
2287 dir_renames);
2288 if (!dir_rename_ent)
2289 continue;
2290
2291 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
2292 if (!new_path)
2293 /*
2294 * dir_rename_ent->non_unique_new_path is true, which
2295 * means there is no directory rename for us to use,
2296 * which means it won't cause us any additional
2297 * collisions.
2298 */
2299 continue;
2300 collision_ent = collision_find_entry(collisions, new_path);
2301 if (!collision_ent) {
2302 collision_ent = xcalloc(1,
2303 sizeof(struct collision_entry));
2304 hashmap_entry_init(collision_ent, strhash(new_path));
2305 hashmap_put(collisions, collision_ent);
2306 collision_ent->target_file = new_path;
2307 } else {
2308 free(new_path);
2309 }
2310 string_list_insert(&collision_ent->source_files,
2311 pair->two->path);
2312 }
2313 }
2314
2315 static char *check_for_directory_rename(struct merge_options *o,
2316 const char *path,
2317 struct tree *tree,
2318 struct hashmap *dir_renames,
2319 struct hashmap *dir_rename_exclusions,
2320 struct hashmap *collisions,
2321 int *clean_merge)
2322 {
2323 char *new_path = NULL;
2324 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
2325 struct dir_rename_entry *oentry = NULL;
2326
2327 if (!entry)
2328 return new_path;
2329
2330 /*
2331 * This next part is a little weird. We do not want to do an
2332 * implicit rename into a directory we renamed on our side, because
2333 * that will result in a spurious rename/rename(1to2) conflict. An
2334 * example:
2335 * Base commit: dumbdir/afile, otherdir/bfile
2336 * Side 1: smrtdir/afile, otherdir/bfile
2337 * Side 2: dumbdir/afile, dumbdir/bfile
2338 * Here, while working on Side 1, we could notice that otherdir was
2339 * renamed/merged to dumbdir, and change the diff_filepair for
2340 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
2341 * 2 will notice the rename from dumbdir to smrtdir, and do the
2342 * transitive rename to move it from dumbdir/bfile to
2343 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
2344 * smrtdir, a rename/rename(1to2) conflict. We really just want
2345 * the file to end up in smrtdir. And the way to achieve that is
2346 * to not let Side1 do the rename to dumbdir, since we know that is
2347 * the source of one of our directory renames.
2348 *
2349 * That's why oentry and dir_rename_exclusions is here.
2350 *
2351 * As it turns out, this also prevents N-way transient rename
2352 * confusion; See testcases 9c and 9d of t6043.
2353 */
2354 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
2355 if (oentry) {
2356 output(o, 1, _("WARNING: Avoiding applying %s -> %s rename "
2357 "to %s, because %s itself was renamed."),
2358 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
2359 } else {
2360 new_path = handle_path_level_conflicts(o, path, entry,
2361 collisions, tree);
2362 *clean_merge &= (new_path != NULL);
2363 }
2364
2365 return new_path;
2366 }
2367
2368 static void apply_directory_rename_modifications(struct merge_options *o,
2369 struct diff_filepair *pair,
2370 char *new_path,
2371 struct rename *re,
2372 struct tree *tree,
2373 struct tree *o_tree,
2374 struct tree *a_tree,
2375 struct tree *b_tree,
2376 struct string_list *entries,
2377 int *clean)
2378 {
2379 struct string_list_item *item;
2380 int stage = (tree == a_tree ? 2 : 3);
2381 int update_wd;
2382
2383 /*
2384 * In all cases where we can do directory rename detection,
2385 * unpack_trees() will have read pair->two->path into the
2386 * index and the working copy. We need to remove it so that
2387 * we can instead place it at new_path. It is guaranteed to
2388 * not be untracked (unpack_trees() would have errored out
2389 * saying the file would have been overwritten), but it might
2390 * be dirty, though.
2391 */
2392 update_wd = !was_dirty(o, pair->two->path);
2393 if (!update_wd)
2394 output(o, 1, _("Refusing to lose dirty file at %s"),
2395 pair->two->path);
2396 remove_file(o, 1, pair->two->path, !update_wd);
2397
2398 /* Find or create a new re->dst_entry */
2399 item = string_list_lookup(entries, new_path);
2400 if (item) {
2401 /*
2402 * Since we're renaming on this side of history, and it's
2403 * due to a directory rename on the other side of history
2404 * (which we only allow when the directory in question no
2405 * longer exists on the other side of history), the
2406 * original entry for re->dst_entry is no longer
2407 * necessary...
2408 */
2409 re->dst_entry->processed = 1;
2410
2411 /*
2412 * ...because we'll be using this new one.
2413 */
2414 re->dst_entry = item->util;
2415 } else {
2416 /*
2417 * re->dst_entry is for the before-dir-rename path, and we
2418 * need it to hold information for the after-dir-rename
2419 * path. Before creating a new entry, we need to mark the
2420 * old one as unnecessary (...unless it is shared by
2421 * src_entry, i.e. this didn't use to be a rename, in which
2422 * case we can just allow the normal processing to happen
2423 * for it).
2424 */
2425 if (pair->status == 'R')
2426 re->dst_entry->processed = 1;
2427
2428 re->dst_entry = insert_stage_data(new_path,
2429 o_tree, a_tree, b_tree,
2430 entries);
2431 item = string_list_insert(entries, new_path);
2432 item->util = re->dst_entry;
2433 }
2434
2435 /*
2436 * Update the stage_data with the information about the path we are
2437 * moving into place. That slot will be empty and available for us
2438 * to write to because of the collision checks in
2439 * handle_path_level_conflicts(). In other words,
2440 * re->dst_entry->stages[stage].oid will be the null_oid, so it's
2441 * open for us to write to.
2442 *
2443 * It may be tempting to actually update the index at this point as
2444 * well, using update_stages_for_stage_data(), but as per the big
2445 * "NOTE" in update_stages(), doing so will modify the current
2446 * in-memory index which will break calls to would_lose_untracked()
2447 * that we need to make. Instead, we need to just make sure that
2448 * the various handle_rename_*() functions update the index
2449 * explicitly rather than relying on unpack_trees() to have done it.
2450 */
2451 get_tree_entry(&tree->object.oid,
2452 pair->two->path,
2453 &re->dst_entry->stages[stage].oid,
2454 &re->dst_entry->stages[stage].mode);
2455
2456 /* Update pair status */
2457 if (pair->status == 'A') {
2458 /*
2459 * Recording rename information for this add makes it look
2460 * like a rename/delete conflict. Make sure we can
2461 * correctly handle this as an add that was moved to a new
2462 * directory instead of reporting a rename/delete conflict.
2463 */
2464 re->add_turned_into_rename = 1;
2465 }
2466 /*
2467 * We don't actually look at pair->status again, but it seems
2468 * pedagogically correct to adjust it.
2469 */
2470 pair->status = 'R';
2471
2472 /*
2473 * Finally, record the new location.
2474 */
2475 pair->two->path = new_path;
2476 }
2477
2478 /*
2479 * Get information of all renames which occurred in 'pairs', making use of
2480 * any implicit directory renames inferred from the other side of history.
2481 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
2482 * to be able to associate the correct cache entries with the rename
2483 * information; tree is always equal to either a_tree or b_tree.
2484 */
2485 static struct string_list *get_renames(struct merge_options *o,
2486 struct diff_queue_struct *pairs,
2487 struct hashmap *dir_renames,
2488 struct hashmap *dir_rename_exclusions,
2489 struct tree *tree,
2490 struct tree *o_tree,
2491 struct tree *a_tree,
2492 struct tree *b_tree,
2493 struct string_list *entries,
2494 int *clean_merge)
2495 {
2496 int i;
2497 struct hashmap collisions;
2498 struct hashmap_iter iter;
2499 struct collision_entry *e;
2500 struct string_list *renames;
2501
2502 compute_collisions(&collisions, dir_renames, pairs);
2503 renames = xcalloc(1, sizeof(struct string_list));
2504
2505 for (i = 0; i < pairs->nr; ++i) {
2506 struct string_list_item *item;
2507 struct rename *re;
2508 struct diff_filepair *pair = pairs->queue[i];
2509 char *new_path; /* non-NULL only with directory renames */
2510
2511 if (pair->status != 'A' && pair->status != 'R') {
2512 diff_free_filepair(pair);
2513 continue;
2514 }
2515 new_path = check_for_directory_rename(o, pair->two->path, tree,
2516 dir_renames,
2517 dir_rename_exclusions,
2518 &collisions,
2519 clean_merge);
2520 if (pair->status != 'R' && !new_path) {
2521 diff_free_filepair(pair);
2522 continue;
2523 }
2524
2525 re = xmalloc(sizeof(*re));
2526 re->processed = 0;
2527 re->add_turned_into_rename = 0;
2528 re->pair = pair;
2529 item = string_list_lookup(entries, re->pair->one->path);
2530 if (!item)
2531 re->src_entry = insert_stage_data(re->pair->one->path,
2532 o_tree, a_tree, b_tree, entries);
2533 else
2534 re->src_entry = item->util;
2535
2536 item = string_list_lookup(entries, re->pair->two->path);
2537 if (!item)
2538 re->dst_entry = insert_stage_data(re->pair->two->path,
2539 o_tree, a_tree, b_tree, entries);
2540 else
2541 re->dst_entry = item->util;
2542 item = string_list_insert(renames, pair->one->path);
2543 item->util = re;
2544 if (new_path)
2545 apply_directory_rename_modifications(o, pair, new_path,
2546 re, tree, o_tree,
2547 a_tree, b_tree,
2548 entries,
2549 clean_merge);
2550 }
2551
2552 hashmap_iter_init(&collisions, &iter);
2553 while ((e = hashmap_iter_next(&iter))) {
2554 free(e->target_file);
2555 string_list_clear(&e->source_files, 0);
2556 }
2557 hashmap_free(&collisions, 1);
2558 return renames;
2559 }
2560
2561 static int process_renames(struct merge_options *o,
2562 struct string_list *a_renames,
2563 struct string_list *b_renames)
2564 {
2565 int clean_merge = 1, i, j;
2566 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2567 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2568 const struct rename *sre;
2569
2570 for (i = 0; i < a_renames->nr; i++) {
2571 sre = a_renames->items[i].util;
2572 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2573 = (void *)sre;
2574 }
2575 for (i = 0; i < b_renames->nr; i++) {
2576 sre = b_renames->items[i].util;
2577 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2578 = (void *)sre;
2579 }
2580
2581 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2582 struct string_list *renames1, *renames2Dst;
2583 struct rename *ren1 = NULL, *ren2 = NULL;
2584 const char *branch1, *branch2;
2585 const char *ren1_src, *ren1_dst;
2586 struct string_list_item *lookup;
2587
2588 if (i >= a_renames->nr) {
2589 ren2 = b_renames->items[j++].util;
2590 } else if (j >= b_renames->nr) {
2591 ren1 = a_renames->items[i++].util;
2592 } else {
2593 int compare = strcmp(a_renames->items[i].string,
2594 b_renames->items[j].string);
2595 if (compare <= 0)
2596 ren1 = a_renames->items[i++].util;
2597 if (compare >= 0)
2598 ren2 = b_renames->items[j++].util;
2599 }
2600
2601 /* TODO: refactor, so that 1/2 are not needed */
2602 if (ren1) {
2603 renames1 = a_renames;
2604 renames2Dst = &b_by_dst;
2605 branch1 = o->branch1;
2606 branch2 = o->branch2;
2607 } else {
2608 renames1 = b_renames;
2609 renames2Dst = &a_by_dst;
2610 branch1 = o->branch2;
2611 branch2 = o->branch1;
2612 SWAP(ren2, ren1);
2613 }
2614
2615 if (ren1->processed)
2616 continue;
2617 ren1->processed = 1;
2618 ren1->dst_entry->processed = 1;
2619 /* BUG: We should only mark src_entry as processed if we
2620 * are not dealing with a rename + add-source case.
2621 */
2622 ren1->src_entry->processed = 1;
2623
2624 ren1_src = ren1->pair->one->path;
2625 ren1_dst = ren1->pair->two->path;
2626
2627 if (ren2) {
2628 /* One file renamed on both sides */
2629 const char *ren2_src = ren2->pair->one->path;
2630 const char *ren2_dst = ren2->pair->two->path;
2631 enum rename_type rename_type;
2632 if (strcmp(ren1_src, ren2_src) != 0)
2633 BUG("ren1_src != ren2_src");
2634 ren2->dst_entry->processed = 1;
2635 ren2->processed = 1;
2636 if (strcmp(ren1_dst, ren2_dst) != 0) {
2637 rename_type = RENAME_ONE_FILE_TO_TWO;
2638 clean_merge = 0;
2639 } else {
2640 rename_type = RENAME_ONE_FILE_TO_ONE;
2641 /* BUG: We should only remove ren1_src in
2642 * the base stage (think of rename +
2643 * add-source cases).
2644 */
2645 remove_file(o, 1, ren1_src, 1);
2646 update_entry(ren1->dst_entry,
2647 ren1->pair->one,
2648 ren1->pair->two,
2649 ren2->pair->two);
2650 }
2651 setup_rename_conflict_info(rename_type,
2652 ren1->pair,
2653 ren2->pair,
2654 branch1,
2655 branch2,
2656 ren1->dst_entry,
2657 ren2->dst_entry,
2658 o,
2659 NULL,
2660 NULL);
2661 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2662 /* Two different files renamed to the same thing */
2663 char *ren2_dst;
2664 ren2 = lookup->util;
2665 ren2_dst = ren2->pair->two->path;
2666 if (strcmp(ren1_dst, ren2_dst) != 0)
2667 BUG("ren1_dst != ren2_dst");
2668
2669 clean_merge = 0;
2670 ren2->processed = 1;
2671 /*
2672 * BUG: We should only mark src_entry as processed
2673 * if we are not dealing with a rename + add-source
2674 * case.
2675 */
2676 ren2->src_entry->processed = 1;
2677
2678 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2679 ren1->pair,
2680 ren2->pair,
2681 branch1,
2682 branch2,
2683 ren1->dst_entry,
2684 ren2->dst_entry,
2685 o,
2686 ren1->src_entry,
2687 ren2->src_entry);
2688
2689 } else {
2690 /* Renamed in 1, maybe changed in 2 */
2691 /* we only use sha1 and mode of these */
2692 struct diff_filespec src_other, dst_other;
2693 int try_merge;
2694
2695 /*
2696 * unpack_trees loads entries from common-commit
2697 * into stage 1, from head-commit into stage 2, and
2698 * from merge-commit into stage 3. We keep track
2699 * of which side corresponds to the rename.
2700 */
2701 int renamed_stage = a_renames == renames1 ? 2 : 3;
2702 int other_stage = a_renames == renames1 ? 3 : 2;
2703
2704 /* BUG: We should only remove ren1_src in the base
2705 * stage and in other_stage (think of rename +
2706 * add-source case).
2707 */
2708 remove_file(o, 1, ren1_src,
2709 renamed_stage == 2 || !was_tracked(o, ren1_src));
2710
2711 oidcpy(&src_other.oid,
2712 &ren1->src_entry->stages[other_stage].oid);
2713 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2714 oidcpy(&dst_other.oid,
2715 &ren1->dst_entry->stages[other_stage].oid);
2716 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2717 try_merge = 0;
2718
2719 if (oid_eq(&src_other.oid, &null_oid) &&
2720 ren1->add_turned_into_rename) {
2721 setup_rename_conflict_info(RENAME_VIA_DIR,
2722 ren1->pair,
2723 NULL,
2724 branch1,
2725 branch2,
2726 ren1->dst_entry,
2727 NULL,
2728 o,
2729 NULL,
2730 NULL);
2731 } else if (oid_eq(&src_other.oid, &null_oid)) {
2732 setup_rename_conflict_info(RENAME_DELETE,
2733 ren1->pair,
2734 NULL,
2735 branch1,
2736 branch2,
2737 ren1->dst_entry,
2738 NULL,
2739 o,
2740 NULL,
2741 NULL);
2742 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2743 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2744 /*
2745 * Added file on the other side identical to
2746 * the file being renamed: clean merge.
2747 * Also, there is no need to overwrite the
2748 * file already in the working copy, so call
2749 * update_file_flags() instead of
2750 * update_file().
2751 */
2752 if (update_file_flags(o,
2753 &ren1->pair->two->oid,
2754 ren1->pair->two->mode,
2755 ren1_dst,
2756 1, /* update_cache */
2757 0 /* update_wd */))
2758 clean_merge = -1;
2759 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2760 clean_merge = 0;
2761 try_merge = 1;
2762 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
2763 "%s added in %s"),
2764 ren1_src, ren1_dst, branch1,
2765 ren1_dst, branch2);
2766 if (o->call_depth) {
2767 struct merge_file_info mfi;
2768 if (merge_file_one(o, ren1_dst, &null_oid, 0,
2769 &ren1->pair->two->oid,
2770 ren1->pair->two->mode,
2771 &dst_other.oid,
2772 dst_other.mode,
2773 branch1, branch2, &mfi)) {
2774 clean_merge = -1;
2775 goto cleanup_and_return;
2776 }
2777 output(o, 1, _("Adding merged %s"), ren1_dst);
2778 if (update_file(o, 0, &mfi.oid,
2779 mfi.mode, ren1_dst))
2780 clean_merge = -1;
2781 try_merge = 0;
2782 } else {
2783 char *new_path = unique_path(o, ren1_dst, branch2);
2784 output(o, 1, _("Adding as %s instead"), new_path);
2785 if (update_file(o, 0, &dst_other.oid,
2786 dst_other.mode, new_path))
2787 clean_merge = -1;
2788 free(new_path);
2789 }
2790 } else
2791 try_merge = 1;
2792
2793 if (clean_merge < 0)
2794 goto cleanup_and_return;
2795 if (try_merge) {
2796 struct diff_filespec *one, *a, *b;
2797 src_other.path = (char *)ren1_src;
2798
2799 one = ren1->pair->one;
2800 if (a_renames == renames1) {
2801 a = ren1->pair->two;
2802 b = &src_other;
2803 } else {
2804 b = ren1->pair->two;
2805 a = &src_other;
2806 }
2807 update_entry(ren1->dst_entry, one, a, b);
2808 setup_rename_conflict_info(RENAME_NORMAL,
2809 ren1->pair,
2810 NULL,
2811 branch1,
2812 NULL,
2813 ren1->dst_entry,
2814 NULL,
2815 o,
2816 NULL,
2817 NULL);
2818 }
2819 }
2820 }
2821 cleanup_and_return:
2822 string_list_clear(&a_by_dst, 0);
2823 string_list_clear(&b_by_dst, 0);
2824
2825 return clean_merge;
2826 }
2827
2828 struct rename_info {
2829 struct string_list *head_renames;
2830 struct string_list *merge_renames;
2831 };
2832
2833 static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2834 struct hashmap *dir_renames)
2835 {
2836 struct hashmap_iter iter;
2837 struct dir_rename_entry *e;
2838
2839 hashmap_iter_init(dir_renames, &iter);
2840 while ((e = hashmap_iter_next(&iter))) {
2841 free(e->dir);
2842 strbuf_release(&e->new_dir);
2843 /* possible_new_dirs already cleared in get_directory_renames */
2844 }
2845 hashmap_free(dir_renames, 1);
2846 free(dir_renames);
2847
2848 free(pairs->queue);
2849 free(pairs);
2850 }
2851
2852 static int detect_and_process_renames(struct merge_options *o,
2853 struct tree *common,
2854 struct tree *head,
2855 struct tree *merge,
2856 struct string_list *entries,
2857 struct rename_info *ri)
2858 {
2859 struct diff_queue_struct *head_pairs, *merge_pairs;
2860 struct hashmap *dir_re_head, *dir_re_merge;
2861 int clean = 1;
2862
2863 ri->head_renames = NULL;
2864 ri->merge_renames = NULL;
2865
2866 if (!merge_detect_rename(o))
2867 return 1;
2868
2869 head_pairs = get_diffpairs(o, common, head);
2870 merge_pairs = get_diffpairs(o, common, merge);
2871
2872 if (o->detect_directory_renames) {
2873 dir_re_head = get_directory_renames(head_pairs, head);
2874 dir_re_merge = get_directory_renames(merge_pairs, merge);
2875
2876 handle_directory_level_conflicts(o,
2877 dir_re_head, head,
2878 dir_re_merge, merge);
2879 } else {
2880 dir_re_head = xmalloc(sizeof(*dir_re_head));
2881 dir_re_merge = xmalloc(sizeof(*dir_re_merge));
2882 dir_rename_init(dir_re_head);
2883 dir_rename_init(dir_re_merge);
2884 }
2885
2886 ri->head_renames = get_renames(o, head_pairs,
2887 dir_re_merge, dir_re_head, head,
2888 common, head, merge, entries,
2889 &clean);
2890 if (clean < 0)
2891 goto cleanup;
2892 ri->merge_renames = get_renames(o, merge_pairs,
2893 dir_re_head, dir_re_merge, merge,
2894 common, head, merge, entries,
2895 &clean);
2896 if (clean < 0)
2897 goto cleanup;
2898 clean &= process_renames(o, ri->head_renames, ri->merge_renames);
2899
2900 cleanup:
2901 /*
2902 * Some cleanup is deferred until cleanup_renames() because the
2903 * data structures are still needed and referenced in
2904 * process_entry(). But there are a few things we can free now.
2905 */
2906 initial_cleanup_rename(head_pairs, dir_re_head);
2907 initial_cleanup_rename(merge_pairs, dir_re_merge);
2908
2909 return clean;
2910 }
2911
2912 static void final_cleanup_rename(struct string_list *rename)
2913 {
2914 const struct rename *re;
2915 int i;
2916
2917 if (rename == NULL)
2918 return;
2919
2920 for (i = 0; i < rename->nr; i++) {
2921 re = rename->items[i].util;
2922 diff_free_filepair(re->pair);
2923 }
2924 string_list_clear(rename, 1);
2925 free(rename);
2926 }
2927
2928 static void final_cleanup_renames(struct rename_info *re_info)
2929 {
2930 final_cleanup_rename(re_info->head_renames);
2931 final_cleanup_rename(re_info->merge_renames);
2932 }
2933
2934 static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
2935 {
2936 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
2937 }
2938
2939 static int read_oid_strbuf(struct merge_options *o,
2940 const struct object_id *oid,
2941 struct strbuf *dst)
2942 {
2943 void *buf;
2944 enum object_type type;
2945 unsigned long size;
2946 buf = read_object_file(oid, &type, &size);
2947 if (!buf)
2948 return err(o, _("cannot read object %s"), oid_to_hex(oid));
2949 if (type != OBJ_BLOB) {
2950 free(buf);
2951 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
2952 }
2953 strbuf_attach(dst, buf, size, size + 1);
2954 return 0;
2955 }
2956
2957 static int blob_unchanged(struct merge_options *opt,
2958 const struct object_id *o_oid,
2959 unsigned o_mode,
2960 const struct object_id *a_oid,
2961 unsigned a_mode,
2962 int renormalize, const char *path)
2963 {
2964 struct strbuf o = STRBUF_INIT;
2965 struct strbuf a = STRBUF_INIT;
2966 int ret = 0; /* assume changed for safety */
2967
2968 if (a_mode != o_mode)
2969 return 0;
2970 if (oid_eq(o_oid, a_oid))
2971 return 1;
2972 if (!renormalize)
2973 return 0;
2974
2975 assert(o_oid && a_oid);
2976 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
2977 goto error_return;
2978 /*
2979 * Note: binary | is used so that both renormalizations are
2980 * performed. Comparison can be skipped if both files are
2981 * unchanged since their sha1s have already been compared.
2982 */
2983 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
2984 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
2985 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
2986
2987 error_return:
2988 strbuf_release(&o);
2989 strbuf_release(&a);
2990 return ret;
2991 }
2992
2993 static int handle_modify_delete(struct merge_options *o,
2994 const char *path,
2995 struct object_id *o_oid, int o_mode,
2996 struct object_id *a_oid, int a_mode,
2997 struct object_id *b_oid, int b_mode)
2998 {
2999 const char *modify_branch, *delete_branch;
3000 struct object_id *changed_oid;
3001 int changed_mode;
3002
3003 if (a_oid) {
3004 modify_branch = o->branch1;
3005 delete_branch = o->branch2;
3006 changed_oid = a_oid;
3007 changed_mode = a_mode;
3008 } else {
3009 modify_branch = o->branch2;
3010 delete_branch = o->branch1;
3011 changed_oid = b_oid;
3012 changed_mode = b_mode;
3013 }
3014
3015 return handle_change_delete(o,
3016 path, NULL,
3017 o_oid, o_mode,
3018 changed_oid, changed_mode,
3019 modify_branch, delete_branch,
3020 _("modify"), _("modified"));
3021 }
3022
3023 static int merge_content(struct merge_options *o,
3024 const char *path,
3025 int is_dirty,
3026 struct object_id *o_oid, int o_mode,
3027 struct object_id *a_oid, int a_mode,
3028 struct object_id *b_oid, int b_mode,
3029 struct rename_conflict_info *rename_conflict_info)
3030 {
3031 const char *reason = _("content");
3032 const char *path1 = NULL, *path2 = NULL;
3033 struct merge_file_info mfi;
3034 struct diff_filespec one, a, b;
3035 unsigned df_conflict_remains = 0;
3036
3037 if (!o_oid) {
3038 reason = _("add/add");
3039 o_oid = (struct object_id *)&null_oid;
3040 }
3041 one.path = a.path = b.path = (char *)path;
3042 oidcpy(&one.oid, o_oid);
3043 one.mode = o_mode;
3044 oidcpy(&a.oid, a_oid);
3045 a.mode = a_mode;
3046 oidcpy(&b.oid, b_oid);
3047 b.mode = b_mode;
3048
3049 if (rename_conflict_info) {
3050 struct diff_filepair *pair1 = rename_conflict_info->pair1;
3051
3052 path1 = (o->branch1 == rename_conflict_info->branch1) ?
3053 pair1->two->path : pair1->one->path;
3054 /* If rename_conflict_info->pair2 != NULL, we are in
3055 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
3056 * normal rename.
3057 */
3058 path2 = (rename_conflict_info->pair2 ||
3059 o->branch2 == rename_conflict_info->branch1) ?
3060 pair1->two->path : pair1->one->path;
3061
3062 if (dir_in_way(path, !o->call_depth,
3063 S_ISGITLINK(pair1->two->mode)))
3064 df_conflict_remains = 1;
3065 }
3066 if (merge_file_special_markers(o, &one, &a, &b, path,
3067 o->branch1, path1,
3068 o->branch2, path2, &mfi))
3069 return -1;
3070
3071 /*
3072 * We can skip updating the working tree file iff:
3073 * a) The merge is clean
3074 * b) The merge matches what was in HEAD (content, mode, pathname)
3075 * c) The target path is usable (i.e. not involved in D/F conflict)
3076 */
3077 if (mfi.clean &&
3078 was_tracked_and_matches(o, path, &mfi.oid, mfi.mode) &&
3079 !df_conflict_remains) {
3080 int pos;
3081 struct cache_entry *ce;
3082
3083 output(o, 3, _("Skipped %s (merged same as existing)"), path);
3084 if (add_cacheinfo(o, mfi.mode, &mfi.oid, path,
3085 0, (!o->call_depth && !is_dirty), 0))
3086 return -1;
3087 /*
3088 * However, add_cacheinfo() will delete the old cache entry
3089 * and add a new one. We need to copy over any skip_worktree
3090 * flag to avoid making the file appear as if it were
3091 * deleted by the user.
3092 */
3093 pos = index_name_pos(&o->orig_index, path, strlen(path));
3094 ce = o->orig_index.cache[pos];
3095 if (ce_skip_worktree(ce)) {
3096 pos = index_name_pos(&the_index, path, strlen(path));
3097 ce = the_index.cache[pos];
3098 ce->ce_flags |= CE_SKIP_WORKTREE;
3099 }
3100 return mfi.clean;
3101 }
3102
3103 if (!mfi.clean) {
3104 if (S_ISGITLINK(mfi.mode))
3105 reason = _("submodule");
3106 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
3107 reason, path);
3108 if (rename_conflict_info && !df_conflict_remains)
3109 if (update_stages(o, path, &one, &a, &b))
3110 return -1;
3111 }
3112
3113 if (df_conflict_remains || is_dirty) {
3114 char *new_path;
3115 if (o->call_depth) {
3116 remove_file_from_cache(path);
3117 } else {
3118 if (!mfi.clean) {
3119 if (update_stages(o, path, &one, &a, &b))
3120 return -1;
3121 } else {
3122 int file_from_stage2 = was_tracked(o, path);
3123 struct diff_filespec merged;
3124 oidcpy(&merged.oid, &mfi.oid);
3125 merged.mode = mfi.mode;
3126
3127 if (update_stages(o, path, NULL,
3128 file_from_stage2 ? &merged : NULL,
3129 file_from_stage2 ? NULL : &merged))
3130 return -1;
3131 }
3132
3133 }
3134 new_path = unique_path(o, path, rename_conflict_info->branch1);
3135 if (is_dirty) {
3136 output(o, 1, _("Refusing to lose dirty file at %s"),
3137 path);
3138 }
3139 output(o, 1, _("Adding as %s instead"), new_path);
3140 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
3141 free(new_path);
3142 return -1;
3143 }
3144 free(new_path);
3145 mfi.clean = 0;
3146 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
3147 return -1;
3148 return !is_dirty && mfi.clean;
3149 }
3150
3151 static int handle_rename_normal(struct merge_options *o,
3152 const char *path,
3153 struct object_id *o_oid, unsigned int o_mode,
3154 struct object_id *a_oid, unsigned int a_mode,
3155 struct object_id *b_oid, unsigned int b_mode,
3156 struct rename_conflict_info *ci)
3157 {
3158 /* Merge the content and write it out */
3159 return merge_content(o, path, was_dirty(o, path),
3160 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3161 ci);
3162 }
3163
3164 /* Per entry merge function */
3165 static int process_entry(struct merge_options *o,
3166 const char *path, struct stage_data *entry)
3167 {
3168 int clean_merge = 1;
3169 int normalize = o->renormalize;
3170 unsigned o_mode = entry->stages[1].mode;
3171 unsigned a_mode = entry->stages[2].mode;
3172 unsigned b_mode = entry->stages[3].mode;
3173 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
3174 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
3175 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
3176
3177 entry->processed = 1;
3178 if (entry->rename_conflict_info) {
3179 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
3180 switch (conflict_info->rename_type) {
3181 case RENAME_NORMAL:
3182 case RENAME_ONE_FILE_TO_ONE:
3183 clean_merge = handle_rename_normal(o,
3184 path,
3185 o_oid, o_mode,
3186 a_oid, a_mode,
3187 b_oid, b_mode,
3188 conflict_info);
3189 break;
3190 case RENAME_VIA_DIR:
3191 clean_merge = 1;
3192 if (handle_rename_via_dir(o,
3193 conflict_info->pair1,
3194 conflict_info->branch1,
3195 conflict_info->branch2))
3196 clean_merge = -1;
3197 break;
3198 case RENAME_DELETE:
3199 clean_merge = 0;
3200 if (handle_rename_delete(o,
3201 conflict_info->pair1,
3202 conflict_info->branch1,
3203 conflict_info->branch2))
3204 clean_merge = -1;
3205 break;
3206 case RENAME_ONE_FILE_TO_TWO:
3207 clean_merge = 0;
3208 if (handle_rename_rename_1to2(o, conflict_info))
3209 clean_merge = -1;
3210 break;
3211 case RENAME_TWO_FILES_TO_ONE:
3212 clean_merge = 0;
3213 if (handle_rename_rename_2to1(o, conflict_info))
3214 clean_merge = -1;
3215 break;
3216 default:
3217 entry->processed = 0;
3218 break;
3219 }
3220 } else if (o_oid && (!a_oid || !b_oid)) {
3221 /* Case A: Deleted in one */
3222 if ((!a_oid && !b_oid) ||
3223 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
3224 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
3225 /* Deleted in both or deleted in one and
3226 * unchanged in the other */
3227 if (a_oid)
3228 output(o, 2, _("Removing %s"), path);
3229 /* do not touch working file if it did not exist */
3230 remove_file(o, 1, path, !a_oid);
3231 } else {
3232 /* Modify/delete; deleted side may have put a directory in the way */
3233 clean_merge = 0;
3234 if (handle_modify_delete(o, path, o_oid, o_mode,
3235 a_oid, a_mode, b_oid, b_mode))
3236 clean_merge = -1;
3237 }
3238 } else if ((!o_oid && a_oid && !b_oid) ||
3239 (!o_oid && !a_oid && b_oid)) {
3240 /* Case B: Added in one. */
3241 /* [nothing|directory] -> ([nothing|directory], file) */
3242
3243 const char *add_branch;
3244 const char *other_branch;
3245 unsigned mode;
3246 const struct object_id *oid;
3247 const char *conf;
3248
3249 if (a_oid) {
3250 add_branch = o->branch1;
3251 other_branch = o->branch2;
3252 mode = a_mode;
3253 oid = a_oid;
3254 conf = _("file/directory");
3255 } else {
3256 add_branch = o->branch2;
3257 other_branch = o->branch1;
3258 mode = b_mode;
3259 oid = b_oid;
3260 conf = _("directory/file");
3261 }
3262 if (dir_in_way(path,
3263 !o->call_depth && !S_ISGITLINK(a_mode),
3264 0)) {
3265 char *new_path = unique_path(o, path, add_branch);
3266 clean_merge = 0;
3267 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
3268 "Adding %s as %s"),
3269 conf, path, other_branch, path, new_path);
3270 if (update_file(o, 0, oid, mode, new_path))
3271 clean_merge = -1;
3272 else if (o->call_depth)
3273 remove_file_from_cache(path);
3274 free(new_path);
3275 } else {
3276 output(o, 2, _("Adding %s"), path);
3277 /* do not overwrite file if already present */
3278 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
3279 clean_merge = -1;
3280 }
3281 } else if (a_oid && b_oid) {
3282 /* Case C: Added in both (check for same permissions) and */
3283 /* case D: Modified in both, but differently. */
3284 int is_dirty = 0; /* unpack_trees would have bailed if dirty */
3285 clean_merge = merge_content(o, path, is_dirty,
3286 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
3287 NULL);
3288 } else if (!o_oid && !a_oid && !b_oid) {
3289 /*
3290 * this entry was deleted altogether. a_mode == 0 means
3291 * we had that path and want to actively remove it.
3292 */
3293 remove_file(o, 1, path, !a_mode);
3294 } else
3295 BUG("fatal merge failure, shouldn't happen.");
3296
3297 return clean_merge;
3298 }
3299
3300 int merge_trees(struct merge_options *o,
3301 struct tree *head,
3302 struct tree *merge,
3303 struct tree *common,
3304 struct tree **result)
3305 {
3306 int code, clean;
3307 struct strbuf sb = STRBUF_INIT;
3308
3309 if (!o->call_depth && index_has_changes(&the_index, head, &sb)) {
3310 err(o, _("Your local changes to the following files would be overwritten by merge:\n %s"),
3311 sb.buf);
3312 return -1;
3313 }
3314
3315 if (o->subtree_shift) {
3316 merge = shift_tree_object(head, merge, o->subtree_shift);
3317 common = shift_tree_object(head, common, o->subtree_shift);
3318 }
3319
3320 if (oid_eq(&common->object.oid, &merge->object.oid)) {
3321 output(o, 0, _("Already up to date!"));
3322 *result = head;
3323 return 1;
3324 }
3325
3326 code = unpack_trees_start(o, common, head, merge);
3327
3328 if (code != 0) {
3329 if (show(o, 4) || o->call_depth)
3330 err(o, _("merging of trees %s and %s failed"),
3331 oid_to_hex(&head->object.oid),
3332 oid_to_hex(&merge->object.oid));
3333 unpack_trees_finish(o);
3334 return -1;
3335 }
3336
3337 if (unmerged_cache()) {
3338 struct string_list *entries;
3339 struct rename_info re_info;
3340 int i;
3341 /*
3342 * Only need the hashmap while processing entries, so
3343 * initialize it here and free it when we are done running
3344 * through the entries. Keeping it in the merge_options as
3345 * opposed to decaring a local hashmap is for convenience
3346 * so that we don't have to pass it to around.
3347 */
3348 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
3349 get_files_dirs(o, head);
3350 get_files_dirs(o, merge);
3351
3352 entries = get_unmerged();
3353 clean = detect_and_process_renames(o, common, head, merge,
3354 entries, &re_info);
3355 record_df_conflict_files(o, entries);
3356 if (clean < 0)
3357 goto cleanup;
3358 for (i = entries->nr-1; 0 <= i; i--) {
3359 const char *path = entries->items[i].string;
3360 struct stage_data *e = entries->items[i].util;
3361 if (!e->processed) {
3362 int ret = process_entry(o, path, e);
3363 if (!ret)
3364 clean = 0;
3365 else if (ret < 0) {
3366 clean = ret;
3367 goto cleanup;
3368 }
3369 }
3370 }
3371 for (i = 0; i < entries->nr; i++) {
3372 struct stage_data *e = entries->items[i].util;
3373 if (!e->processed)
3374 BUG("unprocessed path??? %s",
3375 entries->items[i].string);
3376 }
3377
3378 cleanup:
3379 final_cleanup_renames(&re_info);
3380
3381 string_list_clear(entries, 1);
3382 free(entries);
3383
3384 hashmap_free(&o->current_file_dir_set, 1);
3385
3386 if (clean < 0) {
3387 unpack_trees_finish(o);
3388 return clean;
3389 }
3390 }
3391 else
3392 clean = 1;
3393
3394 unpack_trees_finish(o);
3395
3396 if (o->call_depth && !(*result = write_tree_from_memory(o)))
3397 return -1;
3398
3399 return clean;
3400 }
3401
3402 static struct commit_list *reverse_commit_list(struct commit_list *list)
3403 {
3404 struct commit_list *next = NULL, *current, *backup;
3405 for (current = list; current; current = backup) {
3406 backup = current->next;
3407 current->next = next;
3408 next = current;
3409 }
3410 return next;
3411 }
3412
3413 /*
3414 * Merge the commits h1 and h2, return the resulting virtual
3415 * commit object and a flag indicating the cleanness of the merge.
3416 */
3417 int merge_recursive(struct merge_options *o,
3418 struct commit *h1,
3419 struct commit *h2,
3420 struct commit_list *ca,
3421 struct commit **result)
3422 {
3423 struct commit_list *iter;
3424 struct commit *merged_common_ancestors;
3425 struct tree *mrtree;
3426 int clean;
3427
3428 if (show(o, 4)) {
3429 output(o, 4, _("Merging:"));
3430 output_commit_title(o, h1);
3431 output_commit_title(o, h2);
3432 }
3433
3434 if (!ca) {
3435 ca = get_merge_bases(h1, h2);
3436 ca = reverse_commit_list(ca);
3437 }
3438
3439 if (show(o, 5)) {
3440 unsigned cnt = commit_list_count(ca);
3441
3442 output(o, 5, Q_("found %u common ancestor:",
3443 "found %u common ancestors:", cnt), cnt);
3444 for (iter = ca; iter; iter = iter->next)
3445 output_commit_title(o, iter->item);
3446 }
3447
3448 merged_common_ancestors = pop_commit(&ca);
3449 if (merged_common_ancestors == NULL) {
3450 /* if there is no common ancestor, use an empty tree */
3451 struct tree *tree;
3452
3453 tree = lookup_tree(the_repository, the_repository->hash_algo->empty_tree);
3454 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
3455 }
3456
3457 for (iter = ca; iter; iter = iter->next) {
3458 const char *saved_b1, *saved_b2;
3459 o->call_depth++;
3460 /*
3461 * When the merge fails, the result contains files
3462 * with conflict markers. The cleanness flag is
3463 * ignored (unless indicating an error), it was never
3464 * actually used, as result of merge_trees has always
3465 * overwritten it: the committed "conflicts" were
3466 * already resolved.
3467 */
3468 discard_cache();
3469 saved_b1 = o->branch1;
3470 saved_b2 = o->branch2;
3471 o->branch1 = "Temporary merge branch 1";
3472 o->branch2 = "Temporary merge branch 2";
3473 if (merge_recursive(o, merged_common_ancestors, iter->item,
3474 NULL, &merged_common_ancestors) < 0)
3475 return -1;
3476 o->branch1 = saved_b1;
3477 o->branch2 = saved_b2;
3478 o->call_depth--;
3479
3480 if (!merged_common_ancestors)
3481 return err(o, _("merge returned no commit"));
3482 }
3483
3484 discard_cache();
3485 if (!o->call_depth)
3486 read_cache();
3487
3488 o->ancestor = "merged common ancestors";
3489 clean = merge_trees(o, get_commit_tree(h1), get_commit_tree(h2),
3490 get_commit_tree(merged_common_ancestors),
3491 &mrtree);
3492 if (clean < 0) {
3493 flush_output(o);
3494 return clean;
3495 }
3496
3497 if (o->call_depth) {
3498 *result = make_virtual_commit(mrtree, "merged tree");
3499 commit_list_insert(h1, &(*result)->parents);
3500 commit_list_insert(h2, &(*result)->parents->next);
3501 }
3502 flush_output(o);
3503 if (!o->call_depth && o->buffer_output < 2)
3504 strbuf_release(&o->obuf);
3505 if (show(o, 2))
3506 diff_warn_rename_limit("merge.renamelimit",
3507 o->needed_rename_limit, 0);
3508 return clean;
3509 }
3510
3511 static struct commit *get_ref(const struct object_id *oid, const char *name)
3512 {
3513 struct object *object;
3514
3515 object = deref_tag(the_repository, parse_object(the_repository, oid),
3516 name,
3517 strlen(name));
3518 if (!object)
3519 return NULL;
3520 if (object->type == OBJ_TREE)
3521 return make_virtual_commit((struct tree*)object, name);
3522 if (object->type != OBJ_COMMIT)
3523 return NULL;
3524 if (parse_commit((struct commit *)object))
3525 return NULL;
3526 return (struct commit *)object;
3527 }
3528
3529 int merge_recursive_generic(struct merge_options *o,
3530 const struct object_id *head,
3531 const struct object_id *merge,
3532 int num_base_list,
3533 const struct object_id **base_list,
3534 struct commit **result)
3535 {
3536 int clean;
3537 struct lock_file lock = LOCK_INIT;
3538 struct commit *head_commit = get_ref(head, o->branch1);
3539 struct commit *next_commit = get_ref(merge, o->branch2);
3540 struct commit_list *ca = NULL;
3541
3542 if (base_list) {
3543 int i;
3544 for (i = 0; i < num_base_list; ++i) {
3545 struct commit *base;
3546 if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i]))))
3547 return err(o, _("Could not parse object '%s'"),
3548 oid_to_hex(base_list[i]));
3549 commit_list_insert(base, &ca);
3550 }
3551 }
3552
3553 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
3554 clean = merge_recursive(o, head_commit, next_commit, ca,
3555 result);
3556 if (clean < 0) {
3557 rollback_lock_file(&lock);
3558 return clean;
3559 }
3560
3561 if (write_locked_index(&the_index, &lock,
3562 COMMIT_LOCK | SKIP_IF_UNCHANGED))
3563 return err(o, _("Unable to write index."));
3564
3565 return clean ? 0 : 1;
3566 }
3567
3568 static void merge_recursive_config(struct merge_options *o)
3569 {
3570 char *value = NULL;
3571 git_config_get_int("merge.verbosity", &o->verbosity);
3572 git_config_get_int("diff.renamelimit", &o->diff_rename_limit);
3573 git_config_get_int("merge.renamelimit", &o->merge_rename_limit);
3574 if (!git_config_get_string("diff.renames", &value)) {
3575 o->diff_detect_rename = git_config_rename("diff.renames", value);
3576 free(value);
3577 }
3578 if (!git_config_get_string("merge.renames", &value)) {
3579 o->merge_detect_rename = git_config_rename("merge.renames", value);
3580 free(value);
3581 }
3582 git_config(git_xmerge_config, NULL);
3583 }
3584
3585 void init_merge_options(struct merge_options *o)
3586 {
3587 const char *merge_verbosity;
3588 memset(o, 0, sizeof(struct merge_options));
3589 o->verbosity = 2;
3590 o->buffer_output = 1;
3591 o->diff_rename_limit = -1;
3592 o->merge_rename_limit = -1;
3593 o->renormalize = 0;
3594 o->diff_detect_rename = -1;
3595 o->merge_detect_rename = -1;
3596 o->detect_directory_renames = 1;
3597 merge_recursive_config(o);
3598 merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
3599 if (merge_verbosity)
3600 o->verbosity = strtol(merge_verbosity, NULL, 10);
3601 if (o->verbosity >= 5)
3602 o->buffer_output = 0;
3603 strbuf_init(&o->obuf, 0);
3604 string_list_init(&o->df_conflict_file_set, 1);
3605 }
3606
3607 int parse_merge_opt(struct merge_options *o, const char *s)
3608 {
3609 const char *arg;
3610
3611