promisor-remote: skip move_to_tail when no-op
[git/git.git] / merge-recursive.c
1 /*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6 #include "cache.h"
7 #include "config.h"
8 #include "advice.h"
9 #include "lockfile.h"
10 #include "cache-tree.h"
11 #include "object-store.h"
12 #include "repository.h"
13 #include "commit.h"
14 #include "blob.h"
15 #include "builtin.h"
16 #include "tree-walk.h"
17 #include "diff.h"
18 #include "diffcore.h"
19 #include "tag.h"
20 #include "alloc.h"
21 #include "unpack-trees.h"
22 #include "string-list.h"
23 #include "xdiff-interface.h"
24 #include "ll-merge.h"
25 #include "attr.h"
26 #include "merge-recursive.h"
27 #include "dir.h"
28 #include "submodule.h"
29 #include "revision.h"
30 #include "commit-reach.h"
31
32 struct path_hashmap_entry {
33 struct hashmap_entry e;
34 char path[FLEX_ARRAY];
35 };
36
37 static int path_hashmap_cmp(const void *cmp_data,
38 const void *entry,
39 const void *entry_or_key,
40 const void *keydata)
41 {
42 const struct path_hashmap_entry *a = entry;
43 const struct path_hashmap_entry *b = entry_or_key;
44 const char *key = keydata;
45
46 if (ignore_case)
47 return strcasecmp(a->path, key ? key : b->path);
48 else
49 return strcmp(a->path, key ? key : b->path);
50 }
51
52 static unsigned int path_hash(const char *path)
53 {
54 return ignore_case ? strihash(path) : strhash(path);
55 }
56
57 static struct dir_rename_entry *dir_rename_find_entry(struct hashmap *hashmap,
58 char *dir)
59 {
60 struct dir_rename_entry key;
61
62 if (dir == NULL)
63 return NULL;
64 hashmap_entry_init(&key, strhash(dir));
65 key.dir = dir;
66 return hashmap_get(hashmap, &key, NULL);
67 }
68
69 static int dir_rename_cmp(const void *unused_cmp_data,
70 const void *entry,
71 const void *entry_or_key,
72 const void *unused_keydata)
73 {
74 const struct dir_rename_entry *e1 = entry;
75 const struct dir_rename_entry *e2 = entry_or_key;
76
77 return strcmp(e1->dir, e2->dir);
78 }
79
80 static void dir_rename_init(struct hashmap *map)
81 {
82 hashmap_init(map, dir_rename_cmp, NULL, 0);
83 }
84
85 static void dir_rename_entry_init(struct dir_rename_entry *entry,
86 char *directory)
87 {
88 hashmap_entry_init(entry, strhash(directory));
89 entry->dir = directory;
90 entry->non_unique_new_dir = 0;
91 strbuf_init(&entry->new_dir, 0);
92 string_list_init(&entry->possible_new_dirs, 0);
93 }
94
95 static struct collision_entry *collision_find_entry(struct hashmap *hashmap,
96 char *target_file)
97 {
98 struct collision_entry key;
99
100 hashmap_entry_init(&key, strhash(target_file));
101 key.target_file = target_file;
102 return hashmap_get(hashmap, &key, NULL);
103 }
104
105 static int collision_cmp(void *unused_cmp_data,
106 const struct collision_entry *e1,
107 const struct collision_entry *e2,
108 const void *unused_keydata)
109 {
110 return strcmp(e1->target_file, e2->target_file);
111 }
112
113 static void collision_init(struct hashmap *map)
114 {
115 hashmap_init(map, (hashmap_cmp_fn) collision_cmp, NULL, 0);
116 }
117
118 static void flush_output(struct merge_options *opt)
119 {
120 if (opt->buffer_output < 2 && opt->obuf.len) {
121 fputs(opt->obuf.buf, stdout);
122 strbuf_reset(&opt->obuf);
123 }
124 }
125
126 static int err(struct merge_options *opt, const char *err, ...)
127 {
128 va_list params;
129
130 if (opt->buffer_output < 2)
131 flush_output(opt);
132 else {
133 strbuf_complete(&opt->obuf, '\n');
134 strbuf_addstr(&opt->obuf, "error: ");
135 }
136 va_start(params, err);
137 strbuf_vaddf(&opt->obuf, err, params);
138 va_end(params);
139 if (opt->buffer_output > 1)
140 strbuf_addch(&opt->obuf, '\n');
141 else {
142 error("%s", opt->obuf.buf);
143 strbuf_reset(&opt->obuf);
144 }
145
146 return -1;
147 }
148
149 static struct tree *shift_tree_object(struct repository *repo,
150 struct tree *one, struct tree *two,
151 const char *subtree_shift)
152 {
153 struct object_id shifted;
154
155 if (!*subtree_shift) {
156 shift_tree(&one->object.oid, &two->object.oid, &shifted, 0);
157 } else {
158 shift_tree_by(&one->object.oid, &two->object.oid, &shifted,
159 subtree_shift);
160 }
161 if (oideq(&two->object.oid, &shifted))
162 return two;
163 return lookup_tree(repo, &shifted);
164 }
165
166 static inline void set_commit_tree(struct commit *c, struct tree *t)
167 {
168 c->maybe_tree = t;
169 }
170
171 static struct commit *make_virtual_commit(struct repository *repo,
172 struct tree *tree,
173 const char *comment)
174 {
175 struct commit *commit = alloc_commit_node(repo);
176
177 set_merge_remote_desc(commit, comment, (struct object *)commit);
178 set_commit_tree(commit, tree);
179 commit->object.parsed = 1;
180 return commit;
181 }
182
183 /*
184 * Since we use get_tree_entry(), which does not put the read object into
185 * the object pool, we cannot rely on a == b.
186 */
187 static int oid_eq(const struct object_id *a, const struct object_id *b)
188 {
189 if (!a && !b)
190 return 2;
191 return a && b && oideq(a, b);
192 }
193
194 enum rename_type {
195 RENAME_NORMAL = 0,
196 RENAME_VIA_DIR,
197 RENAME_ADD,
198 RENAME_DELETE,
199 RENAME_ONE_FILE_TO_ONE,
200 RENAME_ONE_FILE_TO_TWO,
201 RENAME_TWO_FILES_TO_ONE
202 };
203
204 /*
205 * Since we want to write the index eventually, we cannot reuse the index
206 * for these (temporary) data.
207 */
208 struct stage_data {
209 struct diff_filespec stages[4]; /* mostly for oid & mode; maybe path */
210 struct rename_conflict_info *rename_conflict_info;
211 unsigned processed:1;
212 };
213
214 struct rename {
215 unsigned processed:1;
216 struct diff_filepair *pair;
217 const char *branch; /* branch that the rename occurred on */
218 /*
219 * If directory rename detection affected this rename, what was its
220 * original type ('A' or 'R') and it's original destination before
221 * the directory rename (otherwise, '\0' and NULL for these two vars).
222 */
223 char dir_rename_original_type;
224 char *dir_rename_original_dest;
225 /*
226 * Purpose of src_entry and dst_entry:
227 *
228 * If 'before' is renamed to 'after' then src_entry will contain
229 * the versions of 'before' from the merge_base, HEAD, and MERGE in
230 * stages 1, 2, and 3; dst_entry will contain the respective
231 * versions of 'after' in corresponding locations. Thus, we have a
232 * total of six modes and oids, though some will be null. (Stage 0
233 * is ignored; we're interested in handling conflicts.)
234 *
235 * Since we don't turn on break-rewrites by default, neither
236 * src_entry nor dst_entry can have all three of their stages have
237 * non-null oids, meaning at most four of the six will be non-null.
238 * Also, since this is a rename, both src_entry and dst_entry will
239 * have at least one non-null oid, meaning at least two will be
240 * non-null. Of the six oids, a typical rename will have three be
241 * non-null. Only two implies a rename/delete, and four implies a
242 * rename/add.
243 */
244 struct stage_data *src_entry;
245 struct stage_data *dst_entry;
246 };
247
248 struct rename_conflict_info {
249 enum rename_type rename_type;
250 struct rename *ren1;
251 struct rename *ren2;
252 };
253
254 static inline void setup_rename_conflict_info(enum rename_type rename_type,
255 struct merge_options *opt,
256 struct rename *ren1,
257 struct rename *ren2)
258 {
259 struct rename_conflict_info *ci;
260
261 /*
262 * When we have two renames involved, it's easiest to get the
263 * correct things into stage 2 and 3, and to make sure that the
264 * content merge puts HEAD before the other branch if we just
265 * ensure that branch1 == opt->branch1. So, simply flip arguments
266 * around if we don't have that.
267 */
268 if (ren2 && ren1->branch != opt->branch1) {
269 setup_rename_conflict_info(rename_type, opt, ren2, ren1);
270 return;
271 }
272
273 ci = xcalloc(1, sizeof(struct rename_conflict_info));
274 ci->rename_type = rename_type;
275 ci->ren1 = ren1;
276 ci->ren2 = ren2;
277
278 ci->ren1->dst_entry->processed = 0;
279 ci->ren1->dst_entry->rename_conflict_info = ci;
280 if (ren2) {
281 ci->ren2->dst_entry->rename_conflict_info = ci;
282 }
283 }
284
285 static int show(struct merge_options *opt, int v)
286 {
287 return (!opt->call_depth && opt->verbosity >= v) || opt->verbosity >= 5;
288 }
289
290 __attribute__((format (printf, 3, 4)))
291 static void output(struct merge_options *opt, int v, const char *fmt, ...)
292 {
293 va_list ap;
294
295 if (!show(opt, v))
296 return;
297
298 strbuf_addchars(&opt->obuf, ' ', opt->call_depth * 2);
299
300 va_start(ap, fmt);
301 strbuf_vaddf(&opt->obuf, fmt, ap);
302 va_end(ap);
303
304 strbuf_addch(&opt->obuf, '\n');
305 if (!opt->buffer_output)
306 flush_output(opt);
307 }
308
309 static void output_commit_title(struct merge_options *opt, struct commit *commit)
310 {
311 struct merge_remote_desc *desc;
312
313 strbuf_addchars(&opt->obuf, ' ', opt->call_depth * 2);
314 desc = merge_remote_util(commit);
315 if (desc)
316 strbuf_addf(&opt->obuf, "virtual %s\n", desc->name);
317 else {
318 strbuf_add_unique_abbrev(&opt->obuf, &commit->object.oid,
319 DEFAULT_ABBREV);
320 strbuf_addch(&opt->obuf, ' ');
321 if (parse_commit(commit) != 0)
322 strbuf_addstr(&opt->obuf, _("(bad commit)\n"));
323 else {
324 const char *title;
325 const char *msg = get_commit_buffer(commit, NULL);
326 int len = find_commit_subject(msg, &title);
327 if (len)
328 strbuf_addf(&opt->obuf, "%.*s\n", len, title);
329 unuse_commit_buffer(commit, msg);
330 }
331 }
332 flush_output(opt);
333 }
334
335 static int add_cacheinfo(struct merge_options *opt,
336 const struct diff_filespec *blob,
337 const char *path, int stage, int refresh, int options)
338 {
339 struct index_state *istate = opt->repo->index;
340 struct cache_entry *ce;
341 int ret;
342
343 ce = make_cache_entry(istate, blob->mode, &blob->oid, path, stage, 0);
344 if (!ce)
345 return err(opt, _("add_cacheinfo failed for path '%s'; merge aborting."), path);
346
347 ret = add_index_entry(istate, ce, options);
348 if (refresh) {
349 struct cache_entry *nce;
350
351 nce = refresh_cache_entry(istate, ce,
352 CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
353 if (!nce)
354 return err(opt, _("add_cacheinfo failed to refresh for path '%s'; merge aborting."), path);
355 if (nce != ce)
356 ret = add_index_entry(istate, nce, options);
357 }
358 return ret;
359 }
360
361 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
362 {
363 parse_tree(tree);
364 init_tree_desc(desc, tree->buffer, tree->size);
365 }
366
367 static int unpack_trees_start(struct merge_options *opt,
368 struct tree *common,
369 struct tree *head,
370 struct tree *merge)
371 {
372 int rc;
373 struct tree_desc t[3];
374 struct index_state tmp_index = { NULL };
375
376 memset(&opt->unpack_opts, 0, sizeof(opt->unpack_opts));
377 if (opt->call_depth)
378 opt->unpack_opts.index_only = 1;
379 else
380 opt->unpack_opts.update = 1;
381 opt->unpack_opts.merge = 1;
382 opt->unpack_opts.head_idx = 2;
383 opt->unpack_opts.fn = threeway_merge;
384 opt->unpack_opts.src_index = opt->repo->index;
385 opt->unpack_opts.dst_index = &tmp_index;
386 opt->unpack_opts.aggressive = !merge_detect_rename(opt);
387 setup_unpack_trees_porcelain(&opt->unpack_opts, "merge");
388
389 init_tree_desc_from_tree(t+0, common);
390 init_tree_desc_from_tree(t+1, head);
391 init_tree_desc_from_tree(t+2, merge);
392
393 rc = unpack_trees(3, t, &opt->unpack_opts);
394 cache_tree_free(&opt->repo->index->cache_tree);
395
396 /*
397 * Update opt->repo->index to match the new results, AFTER saving a copy
398 * in opt->orig_index. Update src_index to point to the saved copy.
399 * (verify_uptodate() checks src_index, and the original index is
400 * the one that had the necessary modification timestamps.)
401 */
402 opt->orig_index = *opt->repo->index;
403 *opt->repo->index = tmp_index;
404 opt->unpack_opts.src_index = &opt->orig_index;
405
406 return rc;
407 }
408
409 static void unpack_trees_finish(struct merge_options *opt)
410 {
411 discard_index(&opt->orig_index);
412 clear_unpack_trees_porcelain(&opt->unpack_opts);
413 }
414
415 struct tree *write_tree_from_memory(struct merge_options *opt)
416 {
417 struct tree *result = NULL;
418 struct index_state *istate = opt->repo->index;
419
420 if (unmerged_index(istate)) {
421 int i;
422 fprintf(stderr, "BUG: There are unmerged index entries:\n");
423 for (i = 0; i < istate->cache_nr; i++) {
424 const struct cache_entry *ce = istate->cache[i];
425 if (ce_stage(ce))
426 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
427 (int)ce_namelen(ce), ce->name);
428 }
429 BUG("unmerged index entries in merge-recursive.c");
430 }
431
432 if (!istate->cache_tree)
433 istate->cache_tree = cache_tree();
434
435 if (!cache_tree_fully_valid(istate->cache_tree) &&
436 cache_tree_update(istate, 0) < 0) {
437 err(opt, _("error building trees"));
438 return NULL;
439 }
440
441 result = lookup_tree(opt->repo, &istate->cache_tree->oid);
442
443 return result;
444 }
445
446 static int save_files_dirs(const struct object_id *oid,
447 struct strbuf *base, const char *path,
448 unsigned int mode, int stage, void *context)
449 {
450 struct path_hashmap_entry *entry;
451 int baselen = base->len;
452 struct merge_options *opt = context;
453
454 strbuf_addstr(base, path);
455
456 FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
457 hashmap_entry_init(entry, path_hash(entry->path));
458 hashmap_add(&opt->current_file_dir_set, entry);
459
460 strbuf_setlen(base, baselen);
461 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
462 }
463
464 static void get_files_dirs(struct merge_options *opt, struct tree *tree)
465 {
466 struct pathspec match_all;
467 memset(&match_all, 0, sizeof(match_all));
468 read_tree_recursive(the_repository, tree, "", 0, 0,
469 &match_all, save_files_dirs, opt);
470 }
471
472 static int get_tree_entry_if_blob(const struct object_id *tree,
473 const char *path,
474 struct diff_filespec *dfs)
475 {
476 int ret;
477
478 ret = get_tree_entry(tree, path, &dfs->oid, &dfs->mode);
479 if (S_ISDIR(dfs->mode)) {
480 oidcpy(&dfs->oid, &null_oid);
481 dfs->mode = 0;
482 }
483 return ret;
484 }
485
486 /*
487 * Returns an index_entry instance which doesn't have to correspond to
488 * a real cache entry in Git's index.
489 */
490 static struct stage_data *insert_stage_data(const char *path,
491 struct tree *o, struct tree *a, struct tree *b,
492 struct string_list *entries)
493 {
494 struct string_list_item *item;
495 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
496 get_tree_entry_if_blob(&o->object.oid, path, &e->stages[1]);
497 get_tree_entry_if_blob(&a->object.oid, path, &e->stages[2]);
498 get_tree_entry_if_blob(&b->object.oid, path, &e->stages[3]);
499 item = string_list_insert(entries, path);
500 item->util = e;
501 return e;
502 }
503
504 /*
505 * Create a dictionary mapping file names to stage_data objects. The
506 * dictionary contains one entry for every path with a non-zero stage entry.
507 */
508 static struct string_list *get_unmerged(struct index_state *istate)
509 {
510 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
511 int i;
512
513 unmerged->strdup_strings = 1;
514
515 for (i = 0; i < istate->cache_nr; i++) {
516 struct string_list_item *item;
517 struct stage_data *e;
518 const struct cache_entry *ce = istate->cache[i];
519 if (!ce_stage(ce))
520 continue;
521
522 item = string_list_lookup(unmerged, ce->name);
523 if (!item) {
524 item = string_list_insert(unmerged, ce->name);
525 item->util = xcalloc(1, sizeof(struct stage_data));
526 }
527 e = item->util;
528 e->stages[ce_stage(ce)].mode = ce->ce_mode;
529 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
530 }
531
532 return unmerged;
533 }
534
535 static int string_list_df_name_compare(const char *one, const char *two)
536 {
537 int onelen = strlen(one);
538 int twolen = strlen(two);
539 /*
540 * Here we only care that entries for D/F conflicts are
541 * adjacent, in particular with the file of the D/F conflict
542 * appearing before files below the corresponding directory.
543 * The order of the rest of the list is irrelevant for us.
544 *
545 * To achieve this, we sort with df_name_compare and provide
546 * the mode S_IFDIR so that D/F conflicts will sort correctly.
547 * We use the mode S_IFDIR for everything else for simplicity,
548 * since in other cases any changes in their order due to
549 * sorting cause no problems for us.
550 */
551 int cmp = df_name_compare(one, onelen, S_IFDIR,
552 two, twolen, S_IFDIR);
553 /*
554 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
555 * that 'foo' comes before 'foo/bar'.
556 */
557 if (cmp)
558 return cmp;
559 return onelen - twolen;
560 }
561
562 static void record_df_conflict_files(struct merge_options *opt,
563 struct string_list *entries)
564 {
565 /* If there is a D/F conflict and the file for such a conflict
566 * currently exists in the working tree, we want to allow it to be
567 * removed to make room for the corresponding directory if needed.
568 * The files underneath the directories of such D/F conflicts will
569 * be processed before the corresponding file involved in the D/F
570 * conflict. If the D/F directory ends up being removed by the
571 * merge, then we won't have to touch the D/F file. If the D/F
572 * directory needs to be written to the working copy, then the D/F
573 * file will simply be removed (in make_room_for_path()) to make
574 * room for the necessary paths. Note that if both the directory
575 * and the file need to be present, then the D/F file will be
576 * reinstated with a new unique name at the time it is processed.
577 */
578 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
579 const char *last_file = NULL;
580 int last_len = 0;
581 int i;
582
583 /*
584 * If we're merging merge-bases, we don't want to bother with
585 * any working directory changes.
586 */
587 if (opt->call_depth)
588 return;
589
590 /* Ensure D/F conflicts are adjacent in the entries list. */
591 for (i = 0; i < entries->nr; i++) {
592 struct string_list_item *next = &entries->items[i];
593 string_list_append(&df_sorted_entries, next->string)->util =
594 next->util;
595 }
596 df_sorted_entries.cmp = string_list_df_name_compare;
597 string_list_sort(&df_sorted_entries);
598
599 string_list_clear(&opt->df_conflict_file_set, 1);
600 for (i = 0; i < df_sorted_entries.nr; i++) {
601 const char *path = df_sorted_entries.items[i].string;
602 int len = strlen(path);
603 struct stage_data *e = df_sorted_entries.items[i].util;
604
605 /*
606 * Check if last_file & path correspond to a D/F conflict;
607 * i.e. whether path is last_file+'/'+<something>.
608 * If so, record that it's okay to remove last_file to make
609 * room for path and friends if needed.
610 */
611 if (last_file &&
612 len > last_len &&
613 memcmp(path, last_file, last_len) == 0 &&
614 path[last_len] == '/') {
615 string_list_insert(&opt->df_conflict_file_set, last_file);
616 }
617
618 /*
619 * Determine whether path could exist as a file in the
620 * working directory as a possible D/F conflict. This
621 * will only occur when it exists in stage 2 as a
622 * file.
623 */
624 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
625 last_file = path;
626 last_len = len;
627 } else {
628 last_file = NULL;
629 }
630 }
631 string_list_clear(&df_sorted_entries, 0);
632 }
633
634 static int update_stages(struct merge_options *opt, const char *path,
635 const struct diff_filespec *o,
636 const struct diff_filespec *a,
637 const struct diff_filespec *b)
638 {
639
640 /*
641 * NOTE: It is usually a bad idea to call update_stages on a path
642 * before calling update_file on that same path, since it can
643 * sometimes lead to spurious "refusing to lose untracked file..."
644 * messages from update_file (via make_room_for path via
645 * would_lose_untracked). Instead, reverse the order of the calls
646 * (executing update_file first and then update_stages).
647 */
648 int clear = 1;
649 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
650 if (clear)
651 if (remove_file_from_index(opt->repo->index, path))
652 return -1;
653 if (o)
654 if (add_cacheinfo(opt, o, path, 1, 0, options))
655 return -1;
656 if (a)
657 if (add_cacheinfo(opt, a, path, 2, 0, options))
658 return -1;
659 if (b)
660 if (add_cacheinfo(opt, b, path, 3, 0, options))
661 return -1;
662 return 0;
663 }
664
665 static void update_entry(struct stage_data *entry,
666 struct diff_filespec *o,
667 struct diff_filespec *a,
668 struct diff_filespec *b)
669 {
670 entry->processed = 0;
671 entry->stages[1].mode = o->mode;
672 entry->stages[2].mode = a->mode;
673 entry->stages[3].mode = b->mode;
674 oidcpy(&entry->stages[1].oid, &o->oid);
675 oidcpy(&entry->stages[2].oid, &a->oid);
676 oidcpy(&entry->stages[3].oid, &b->oid);
677 }
678
679 static int remove_file(struct merge_options *opt, int clean,
680 const char *path, int no_wd)
681 {
682 int update_cache = opt->call_depth || clean;
683 int update_working_directory = !opt->call_depth && !no_wd;
684
685 if (update_cache) {
686 if (remove_file_from_index(opt->repo->index, path))
687 return -1;
688 }
689 if (update_working_directory) {
690 if (ignore_case) {
691 struct cache_entry *ce;
692 ce = index_file_exists(opt->repo->index, path, strlen(path),
693 ignore_case);
694 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
695 return 0;
696 }
697 if (remove_path(path))
698 return -1;
699 }
700 return 0;
701 }
702
703 /* add a string to a strbuf, but converting "/" to "_" */
704 static void add_flattened_path(struct strbuf *out, const char *s)
705 {
706 size_t i = out->len;
707 strbuf_addstr(out, s);
708 for (; i < out->len; i++)
709 if (out->buf[i] == '/')
710 out->buf[i] = '_';
711 }
712
713 static char *unique_path(struct merge_options *opt, const char *path, const char *branch)
714 {
715 struct path_hashmap_entry *entry;
716 struct strbuf newpath = STRBUF_INIT;
717 int suffix = 0;
718 size_t base_len;
719
720 strbuf_addf(&newpath, "%s~", path);
721 add_flattened_path(&newpath, branch);
722
723 base_len = newpath.len;
724 while (hashmap_get_from_hash(&opt->current_file_dir_set,
725 path_hash(newpath.buf), newpath.buf) ||
726 (!opt->call_depth && file_exists(newpath.buf))) {
727 strbuf_setlen(&newpath, base_len);
728 strbuf_addf(&newpath, "_%d", suffix++);
729 }
730
731 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
732 hashmap_entry_init(entry, path_hash(entry->path));
733 hashmap_add(&opt->current_file_dir_set, entry);
734 return strbuf_detach(&newpath, NULL);
735 }
736
737 /**
738 * Check whether a directory in the index is in the way of an incoming
739 * file. Return 1 if so. If check_working_copy is non-zero, also
740 * check the working directory. If empty_ok is non-zero, also return
741 * 0 in the case where the working-tree dir exists but is empty.
742 */
743 static int dir_in_way(struct index_state *istate, const char *path,
744 int check_working_copy, int empty_ok)
745 {
746 int pos;
747 struct strbuf dirpath = STRBUF_INIT;
748 struct stat st;
749
750 strbuf_addstr(&dirpath, path);
751 strbuf_addch(&dirpath, '/');
752
753 pos = index_name_pos(istate, dirpath.buf, dirpath.len);
754
755 if (pos < 0)
756 pos = -1 - pos;
757 if (pos < istate->cache_nr &&
758 !strncmp(dirpath.buf, istate->cache[pos]->name, dirpath.len)) {
759 strbuf_release(&dirpath);
760 return 1;
761 }
762
763 strbuf_release(&dirpath);
764 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
765 !(empty_ok && is_empty_dir(path));
766 }
767
768 /*
769 * Returns whether path was tracked in the index before the merge started,
770 * and its oid and mode match the specified values
771 */
772 static int was_tracked_and_matches(struct merge_options *opt, const char *path,
773 const struct diff_filespec *blob)
774 {
775 int pos = index_name_pos(&opt->orig_index, path, strlen(path));
776 struct cache_entry *ce;
777
778 if (0 > pos)
779 /* we were not tracking this path before the merge */
780 return 0;
781
782 /* See if the file we were tracking before matches */
783 ce = opt->orig_index.cache[pos];
784 return (oid_eq(&ce->oid, &blob->oid) && ce->ce_mode == blob->mode);
785 }
786
787 /*
788 * Returns whether path was tracked in the index before the merge started
789 */
790 static int was_tracked(struct merge_options *opt, const char *path)
791 {
792 int pos = index_name_pos(&opt->orig_index, path, strlen(path));
793
794 if (0 <= pos)
795 /* we were tracking this path before the merge */
796 return 1;
797
798 return 0;
799 }
800
801 static int would_lose_untracked(struct merge_options *opt, const char *path)
802 {
803 struct index_state *istate = opt->repo->index;
804
805 /*
806 * This may look like it can be simplified to:
807 * return !was_tracked(opt, path) && file_exists(path)
808 * but it can't. This function needs to know whether path was in
809 * the working tree due to EITHER having been tracked in the index
810 * before the merge OR having been put into the working copy and
811 * index by unpack_trees(). Due to that either-or requirement, we
812 * check the current index instead of the original one.
813 *
814 * Note that we do not need to worry about merge-recursive itself
815 * updating the index after unpack_trees() and before calling this
816 * function, because we strictly require all code paths in
817 * merge-recursive to update the working tree first and the index
818 * second. Doing otherwise would break
819 * update_file()/would_lose_untracked(); see every comment in this
820 * file which mentions "update_stages".
821 */
822 int pos = index_name_pos(istate, path, strlen(path));
823
824 if (pos < 0)
825 pos = -1 - pos;
826 while (pos < istate->cache_nr &&
827 !strcmp(path, istate->cache[pos]->name)) {
828 /*
829 * If stage #0, it is definitely tracked.
830 * If it has stage #2 then it was tracked
831 * before this merge started. All other
832 * cases the path was not tracked.
833 */
834 switch (ce_stage(istate->cache[pos])) {
835 case 0:
836 case 2:
837 return 0;
838 }
839 pos++;
840 }
841 return file_exists(path);
842 }
843
844 static int was_dirty(struct merge_options *opt, const char *path)
845 {
846 struct cache_entry *ce;
847 int dirty = 1;
848
849 if (opt->call_depth || !was_tracked(opt, path))
850 return !dirty;
851
852 ce = index_file_exists(opt->unpack_opts.src_index,
853 path, strlen(path), ignore_case);
854 dirty = verify_uptodate(ce, &opt->unpack_opts) != 0;
855 return dirty;
856 }
857
858 static int make_room_for_path(struct merge_options *opt, const char *path)
859 {
860 int status, i;
861 const char *msg = _("failed to create path '%s'%s");
862
863 /* Unlink any D/F conflict files that are in the way */
864 for (i = 0; i < opt->df_conflict_file_set.nr; i++) {
865 const char *df_path = opt->df_conflict_file_set.items[i].string;
866 size_t pathlen = strlen(path);
867 size_t df_pathlen = strlen(df_path);
868 if (df_pathlen < pathlen &&
869 path[df_pathlen] == '/' &&
870 strncmp(path, df_path, df_pathlen) == 0) {
871 output(opt, 3,
872 _("Removing %s to make room for subdirectory\n"),
873 df_path);
874 unlink(df_path);
875 unsorted_string_list_delete_item(&opt->df_conflict_file_set,
876 i, 0);
877 break;
878 }
879 }
880
881 /* Make sure leading directories are created */
882 status = safe_create_leading_directories_const(path);
883 if (status) {
884 if (status == SCLD_EXISTS)
885 /* something else exists */
886 return err(opt, msg, path, _(": perhaps a D/F conflict?"));
887 return err(opt, msg, path, "");
888 }
889
890 /*
891 * Do not unlink a file in the work tree if we are not
892 * tracking it.
893 */
894 if (would_lose_untracked(opt, path))
895 return err(opt, _("refusing to lose untracked file at '%s'"),
896 path);
897
898 /* Successful unlink is good.. */
899 if (!unlink(path))
900 return 0;
901 /* .. and so is no existing file */
902 if (errno == ENOENT)
903 return 0;
904 /* .. but not some other error (who really cares what?) */
905 return err(opt, msg, path, _(": perhaps a D/F conflict?"));
906 }
907
908 static int update_file_flags(struct merge_options *opt,
909 const struct diff_filespec *contents,
910 const char *path,
911 int update_cache,
912 int update_wd)
913 {
914 int ret = 0;
915
916 if (opt->call_depth)
917 update_wd = 0;
918
919 if (update_wd) {
920 enum object_type type;
921 void *buf;
922 unsigned long size;
923
924 if (S_ISGITLINK(contents->mode)) {
925 /*
926 * We may later decide to recursively descend into
927 * the submodule directory and update its index
928 * and/or work tree, but we do not do that now.
929 */
930 update_wd = 0;
931 goto update_index;
932 }
933
934 buf = read_object_file(&contents->oid, &type, &size);
935 if (!buf)
936 return err(opt, _("cannot read object %s '%s'"),
937 oid_to_hex(&contents->oid), path);
938 if (type != OBJ_BLOB) {
939 ret = err(opt, _("blob expected for %s '%s'"),
940 oid_to_hex(&contents->oid), path);
941 goto free_buf;
942 }
943 if (S_ISREG(contents->mode)) {
944 struct strbuf strbuf = STRBUF_INIT;
945 if (convert_to_working_tree(opt->repo->index, path, buf, size, &strbuf)) {
946 free(buf);
947 size = strbuf.len;
948 buf = strbuf_detach(&strbuf, NULL);
949 }
950 }
951
952 if (make_room_for_path(opt, path) < 0) {
953 update_wd = 0;
954 goto free_buf;
955 }
956 if (S_ISREG(contents->mode) ||
957 (!has_symlinks && S_ISLNK(contents->mode))) {
958 int fd;
959 int mode = (contents->mode & 0100 ? 0777 : 0666);
960
961 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
962 if (fd < 0) {
963 ret = err(opt, _("failed to open '%s': %s"),
964 path, strerror(errno));
965 goto free_buf;
966 }
967 write_in_full(fd, buf, size);
968 close(fd);
969 } else if (S_ISLNK(contents->mode)) {
970 char *lnk = xmemdupz(buf, size);
971 safe_create_leading_directories_const(path);
972 unlink(path);
973 if (symlink(lnk, path))
974 ret = err(opt, _("failed to symlink '%s': %s"),
975 path, strerror(errno));
976 free(lnk);
977 } else
978 ret = err(opt,
979 _("do not know what to do with %06o %s '%s'"),
980 contents->mode, oid_to_hex(&contents->oid), path);
981 free_buf:
982 free(buf);
983 }
984 update_index:
985 if (!ret && update_cache)
986 if (add_cacheinfo(opt, contents, path, 0, update_wd,
987 ADD_CACHE_OK_TO_ADD))
988 return -1;
989 return ret;
990 }
991
992 static int update_file(struct merge_options *opt,
993 int clean,
994 const struct diff_filespec *contents,
995 const char *path)
996 {
997 return update_file_flags(opt, contents, path,
998 opt->call_depth || clean, !opt->call_depth);
999 }
1000
1001 /* Low level file merging, update and removal */
1002
1003 struct merge_file_info {
1004 struct diff_filespec blob; /* mostly use oid & mode; sometimes path */
1005 unsigned clean:1,
1006 merge:1;
1007 };
1008
1009 static int merge_3way(struct merge_options *opt,
1010 mmbuffer_t *result_buf,
1011 const struct diff_filespec *o,
1012 const struct diff_filespec *a,
1013 const struct diff_filespec *b,
1014 const char *branch1,
1015 const char *branch2,
1016 const int extra_marker_size)
1017 {
1018 mmfile_t orig, src1, src2;
1019 struct ll_merge_options ll_opts = {0};
1020 char *base_name, *name1, *name2;
1021 int merge_status;
1022
1023 ll_opts.renormalize = opt->renormalize;
1024 ll_opts.extra_marker_size = extra_marker_size;
1025 ll_opts.xdl_opts = opt->xdl_opts;
1026
1027 if (opt->call_depth) {
1028 ll_opts.virtual_ancestor = 1;
1029 ll_opts.variant = 0;
1030 } else {
1031 switch (opt->recursive_variant) {
1032 case MERGE_RECURSIVE_OURS:
1033 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
1034 break;
1035 case MERGE_RECURSIVE_THEIRS:
1036 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
1037 break;
1038 default:
1039 ll_opts.variant = 0;
1040 break;
1041 }
1042 }
1043
1044 assert(a->path && b->path);
1045 if (strcmp(a->path, b->path) ||
1046 (opt->ancestor != NULL && strcmp(a->path, o->path) != 0)) {
1047 base_name = opt->ancestor == NULL ? NULL :
1048 mkpathdup("%s:%s", opt->ancestor, o->path);
1049 name1 = mkpathdup("%s:%s", branch1, a->path);
1050 name2 = mkpathdup("%s:%s", branch2, b->path);
1051 } else {
1052 base_name = opt->ancestor == NULL ? NULL :
1053 mkpathdup("%s", opt->ancestor);
1054 name1 = mkpathdup("%s", branch1);
1055 name2 = mkpathdup("%s", branch2);
1056 }
1057
1058 read_mmblob(&orig, &o->oid);
1059 read_mmblob(&src1, &a->oid);
1060 read_mmblob(&src2, &b->oid);
1061
1062 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
1063 &src1, name1, &src2, name2,
1064 opt->repo->index, &ll_opts);
1065
1066 free(base_name);
1067 free(name1);
1068 free(name2);
1069 free(orig.ptr);
1070 free(src1.ptr);
1071 free(src2.ptr);
1072 return merge_status;
1073 }
1074
1075 static int find_first_merges(struct repository *repo,
1076 struct object_array *result, const char *path,
1077 struct commit *a, struct commit *b)
1078 {
1079 int i, j;
1080 struct object_array merges = OBJECT_ARRAY_INIT;
1081 struct commit *commit;
1082 int contains_another;
1083
1084 char merged_revision[GIT_MAX_HEXSZ + 2];
1085 const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1086 "--all", merged_revision, NULL };
1087 struct rev_info revs;
1088 struct setup_revision_opt rev_opts;
1089
1090 memset(result, 0, sizeof(struct object_array));
1091 memset(&rev_opts, 0, sizeof(rev_opts));
1092
1093 /* get all revisions that merge commit a */
1094 xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1095 oid_to_hex(&a->object.oid));
1096 repo_init_revisions(repo, &revs, NULL);
1097 rev_opts.submodule = path;
1098 /* FIXME: can't handle linked worktrees in submodules yet */
1099 revs.single_worktree = path != NULL;
1100 setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1101
1102 /* save all revisions from the above list that contain b */
1103 if (prepare_revision_walk(&revs))
1104 die("revision walk setup failed");
1105 while ((commit = get_revision(&revs)) != NULL) {
1106 struct object *o = &(commit->object);
1107 if (in_merge_bases(b, commit))
1108 add_object_array(o, NULL, &merges);
1109 }
1110 reset_revision_walk();
1111
1112 /* Now we've got all merges that contain a and b. Prune all
1113 * merges that contain another found merge and save them in
1114 * result.
1115 */
1116 for (i = 0; i < merges.nr; i++) {
1117 struct commit *m1 = (struct commit *) merges.objects[i].item;
1118
1119 contains_another = 0;
1120 for (j = 0; j < merges.nr; j++) {
1121 struct commit *m2 = (struct commit *) merges.objects[j].item;
1122 if (i != j && in_merge_bases(m2, m1)) {
1123 contains_another = 1;
1124 break;
1125 }
1126 }
1127
1128 if (!contains_another)
1129 add_object_array(merges.objects[i].item, NULL, result);
1130 }
1131
1132 object_array_clear(&merges);
1133 return result->nr;
1134 }
1135
1136 static void print_commit(struct commit *commit)
1137 {
1138 struct strbuf sb = STRBUF_INIT;
1139 struct pretty_print_context ctx = {0};
1140 ctx.date_mode.type = DATE_NORMAL;
1141 format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1142 fprintf(stderr, "%s\n", sb.buf);
1143 strbuf_release(&sb);
1144 }
1145
1146 static int is_valid(const struct diff_filespec *dfs)
1147 {
1148 return dfs->mode != 0 && !is_null_oid(&dfs->oid);
1149 }
1150
1151 static int merge_submodule(struct merge_options *opt,
1152 struct object_id *result, const char *path,
1153 const struct object_id *base, const struct object_id *a,
1154 const struct object_id *b)
1155 {
1156 struct commit *commit_base, *commit_a, *commit_b;
1157 int parent_count;
1158 struct object_array merges;
1159
1160 int i;
1161 int search = !opt->call_depth;
1162
1163 /* store a in result in case we fail */
1164 oidcpy(result, a);
1165
1166 /* we can not handle deletion conflicts */
1167 if (is_null_oid(base))
1168 return 0;
1169 if (is_null_oid(a))
1170 return 0;
1171 if (is_null_oid(b))
1172 return 0;
1173
1174 if (add_submodule_odb(path)) {
1175 output(opt, 1, _("Failed to merge submodule %s (not checked out)"), path);
1176 return 0;
1177 }
1178
1179 if (!(commit_base = lookup_commit_reference(opt->repo, base)) ||
1180 !(commit_a = lookup_commit_reference(opt->repo, a)) ||
1181 !(commit_b = lookup_commit_reference(opt->repo, b))) {
1182 output(opt, 1, _("Failed to merge submodule %s (commits not present)"), path);
1183 return 0;
1184 }
1185
1186 /* check whether both changes are forward */
1187 if (!in_merge_bases(commit_base, commit_a) ||
1188 !in_merge_bases(commit_base, commit_b)) {
1189 output(opt, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
1190 return 0;
1191 }
1192
1193 /* Case #1: a is contained in b or vice versa */
1194 if (in_merge_bases(commit_a, commit_b)) {
1195 oidcpy(result, b);
1196 if (show(opt, 3)) {
1197 output(opt, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1198 output_commit_title(opt, commit_b);
1199 } else if (show(opt, 2))
1200 output(opt, 2, _("Fast-forwarding submodule %s"), path);
1201 else
1202 ; /* no output */
1203
1204 return 1;
1205 }
1206 if (in_merge_bases(commit_b, commit_a)) {
1207 oidcpy(result, a);
1208 if (show(opt, 3)) {
1209 output(opt, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
1210 output_commit_title(opt, commit_a);
1211 } else if (show(opt, 2))
1212 output(opt, 2, _("Fast-forwarding submodule %s"), path);
1213 else
1214 ; /* no output */
1215
1216 return 1;
1217 }
1218
1219 /*
1220 * Case #2: There are one or more merges that contain a and b in
1221 * the submodule. If there is only one, then present it as a
1222 * suggestion to the user, but leave it marked unmerged so the
1223 * user needs to confirm the resolution.
1224 */
1225
1226 /* Skip the search if makes no sense to the calling context. */
1227 if (!search)
1228 return 0;
1229
1230 /* find commit which merges them */
1231 parent_count = find_first_merges(opt->repo, &merges, path,
1232 commit_a, commit_b);
1233 switch (parent_count) {
1234 case 0:
1235 output(opt, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
1236 break;
1237
1238 case 1:
1239 output(opt, 1, _("Failed to merge submodule %s (not fast-forward)"), path);
1240 output(opt, 2, _("Found a possible merge resolution for the submodule:\n"));
1241 print_commit((struct commit *) merges.objects[0].item);
1242 output(opt, 2, _(
1243 "If this is correct simply add it to the index "
1244 "for example\n"
1245 "by using:\n\n"
1246 " git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1247 "which will accept this suggestion.\n"),
1248 oid_to_hex(&merges.objects[0].item->oid), path);
1249 break;
1250
1251 default:
1252 output(opt, 1, _("Failed to merge submodule %s (multiple merges found)"), path);
1253 for (i = 0; i < merges.nr; i++)
1254 print_commit((struct commit *) merges.objects[i].item);
1255 }
1256
1257 object_array_clear(&merges);
1258 return 0;
1259 }
1260
1261 static int merge_mode_and_contents(struct merge_options *opt,
1262 const struct diff_filespec *o,
1263 const struct diff_filespec *a,
1264 const struct diff_filespec *b,
1265 const char *filename,
1266 const char *branch1,
1267 const char *branch2,
1268 const int extra_marker_size,
1269 struct merge_file_info *result)
1270 {
1271 if (opt->branch1 != branch1) {
1272 /*
1273 * It's weird getting a reverse merge with HEAD on the bottom
1274 * side of the conflict markers and the other branch on the
1275 * top. Fix that.
1276 */
1277 return merge_mode_and_contents(opt, o, b, a,
1278 filename,
1279 branch2, branch1,
1280 extra_marker_size, result);
1281 }
1282
1283 result->merge = 0;
1284 result->clean = 1;
1285
1286 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
1287 result->clean = 0;
1288 if (S_ISREG(a->mode)) {
1289 result->blob.mode = a->mode;
1290 oidcpy(&result->blob.oid, &a->oid);
1291 } else {
1292 result->blob.mode = b->mode;
1293 oidcpy(&result->blob.oid, &b->oid);
1294 }
1295 } else {
1296 if (!oid_eq(&a->oid, &o->oid) && !oid_eq(&b->oid, &o->oid))
1297 result->merge = 1;
1298
1299 /*
1300 * Merge modes
1301 */
1302 if (a->mode == b->mode || a->mode == o->mode)
1303 result->blob.mode = b->mode;
1304 else {
1305 result->blob.mode = a->mode;
1306 if (b->mode != o->mode) {
1307 result->clean = 0;
1308 result->merge = 1;
1309 }
1310 }
1311
1312 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &o->oid))
1313 oidcpy(&result->blob.oid, &b->oid);
1314 else if (oid_eq(&b->oid, &o->oid))
1315 oidcpy(&result->blob.oid, &a->oid);
1316 else if (S_ISREG(a->mode)) {
1317 mmbuffer_t result_buf;
1318 int ret = 0, merge_status;
1319
1320 merge_status = merge_3way(opt, &result_buf, o, a, b,
1321 branch1, branch2,
1322 extra_marker_size);
1323
1324 if ((merge_status < 0) || !result_buf.ptr)
1325 ret = err(opt, _("Failed to execute internal merge"));
1326
1327 if (!ret &&
1328 write_object_file(result_buf.ptr, result_buf.size,
1329 blob_type, &result->blob.oid))
1330 ret = err(opt, _("Unable to add %s to database"),
1331 a->path);
1332
1333 free(result_buf.ptr);
1334 if (ret)
1335 return ret;
1336 result->clean = (merge_status == 0);
1337 } else if (S_ISGITLINK(a->mode)) {
1338 result->clean = merge_submodule(opt, &result->blob.oid,
1339 o->path,
1340 &o->oid,
1341 &a->oid,
1342 &b->oid);
1343 } else if (S_ISLNK(a->mode)) {
1344 switch (opt->recursive_variant) {
1345 case MERGE_RECURSIVE_NORMAL:
1346 oidcpy(&result->blob.oid, &a->oid);
1347 if (!oid_eq(&a->oid, &b->oid))
1348 result->clean = 0;
1349 break;
1350 case MERGE_RECURSIVE_OURS:
1351 oidcpy(&result->blob.oid, &a->oid);
1352 break;
1353 case MERGE_RECURSIVE_THEIRS:
1354 oidcpy(&result->blob.oid, &b->oid);
1355 break;
1356 }
1357 } else
1358 BUG("unsupported object type in the tree");
1359 }
1360
1361 if (result->merge)
1362 output(opt, 2, _("Auto-merging %s"), filename);
1363
1364 return 0;
1365 }
1366
1367 static int handle_rename_via_dir(struct merge_options *opt,
1368 struct rename_conflict_info *ci)
1369 {
1370 /*
1371 * Handle file adds that need to be renamed due to directory rename
1372 * detection. This differs from handle_rename_normal, because
1373 * there is no content merge to do; just move the file into the
1374 * desired final location.
1375 */
1376 const struct rename *ren = ci->ren1;
1377 const struct diff_filespec *dest = ren->pair->two;
1378 char *file_path = dest->path;
1379 int mark_conflicted = (opt->detect_directory_renames == 1);
1380 assert(ren->dir_rename_original_dest);
1381
1382 if (!opt->call_depth && would_lose_untracked(opt, dest->path)) {
1383 mark_conflicted = 1;
1384 file_path = unique_path(opt, dest->path, ren->branch);
1385 output(opt, 1, _("Error: Refusing to lose untracked file at %s; "
1386 "writing to %s instead."),
1387 dest->path, file_path);
1388 }
1389
1390 if (mark_conflicted) {
1391 /*
1392 * Write the file in worktree at file_path. In the index,
1393 * only record the file at dest->path in the appropriate
1394 * higher stage.
1395 */
1396 if (update_file(opt, 0, dest, file_path))
1397 return -1;
1398 if (file_path != dest->path)
1399 free(file_path);
1400 if (update_stages(opt, dest->path, NULL,
1401 ren->branch == opt->branch1 ? dest : NULL,
1402 ren->branch == opt->branch1 ? NULL : dest))
1403 return -1;
1404 return 0; /* not clean, but conflicted */
1405 } else {
1406 /* Update dest->path both in index and in worktree */
1407 if (update_file(opt, 1, dest, dest->path))
1408 return -1;
1409 return 1; /* clean */
1410 }
1411 }
1412
1413 static int handle_change_delete(struct merge_options *opt,
1414 const char *path, const char *old_path,
1415 const struct diff_filespec *o,
1416 const struct diff_filespec *changed,
1417 const char *change_branch,
1418 const char *delete_branch,
1419 const char *change, const char *change_past)
1420 {
1421 char *alt_path = NULL;
1422 const char *update_path = path;
1423 int ret = 0;
1424
1425 if (dir_in_way(opt->repo->index, path, !opt->call_depth, 0) ||
1426 (!opt->call_depth && would_lose_untracked(opt, path))) {
1427 update_path = alt_path = unique_path(opt, path, change_branch);
1428 }
1429
1430 if (opt->call_depth) {
1431 /*
1432 * We cannot arbitrarily accept either a_sha or b_sha as
1433 * correct; since there is no true "middle point" between
1434 * them, simply reuse the base version for virtual merge base.
1435 */
1436 ret = remove_file_from_index(opt->repo->index, path);
1437 if (!ret)
1438 ret = update_file(opt, 0, o, update_path);
1439 } else {
1440 /*
1441 * Despite the four nearly duplicate messages and argument
1442 * lists below and the ugliness of the nested if-statements,
1443 * having complete messages makes the job easier for
1444 * translators.
1445 *
1446 * The slight variance among the cases is due to the fact
1447 * that:
1448 * 1) directory/file conflicts (in effect if
1449 * !alt_path) could cause us to need to write the
1450 * file to a different path.
1451 * 2) renames (in effect if !old_path) could mean that
1452 * there are two names for the path that the user
1453 * may know the file by.
1454 */
1455 if (!alt_path) {
1456 if (!old_path) {
1457 output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1458 "and %s in %s. Version %s of %s left in tree."),
1459 change, path, delete_branch, change_past,
1460 change_branch, change_branch, path);
1461 } else {
1462 output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1463 "and %s to %s in %s. Version %s of %s left in tree."),
1464 change, old_path, delete_branch, change_past, path,
1465 change_branch, change_branch, path);
1466 }
1467 } else {
1468 if (!old_path) {
1469 output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1470 "and %s in %s. Version %s of %s left in tree at %s."),
1471 change, path, delete_branch, change_past,
1472 change_branch, change_branch, path, alt_path);
1473 } else {
1474 output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1475 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1476 change, old_path, delete_branch, change_past, path,
1477 change_branch, change_branch, path, alt_path);
1478 }
1479 }
1480 /*
1481 * No need to call update_file() on path when change_branch ==
1482 * opt->branch1 && !alt_path, since that would needlessly touch
1483 * path. We could call update_file_flags() with update_cache=0
1484 * and update_wd=0, but that's a no-op.
1485 */
1486 if (change_branch != opt->branch1 || alt_path)
1487 ret = update_file(opt, 0, changed, update_path);
1488 }
1489 free(alt_path);
1490
1491 return ret;
1492 }
1493
1494 static int handle_rename_delete(struct merge_options *opt,
1495 struct rename_conflict_info *ci)
1496 {
1497 const struct rename *ren = ci->ren1;
1498 const struct diff_filespec *orig = ren->pair->one;
1499 const struct diff_filespec *dest = ren->pair->two;
1500 const char *rename_branch = ren->branch;
1501 const char *delete_branch = (opt->branch1 == ren->branch ?
1502 opt->branch2 : opt->branch1);
1503
1504 if (handle_change_delete(opt,
1505 opt->call_depth ? orig->path : dest->path,
1506 opt->call_depth ? NULL : orig->path,
1507 orig, dest,
1508 rename_branch, delete_branch,
1509 _("rename"), _("renamed")))
1510 return -1;
1511
1512 if (opt->call_depth)
1513 return remove_file_from_index(opt->repo->index, dest->path);
1514 else
1515 return update_stages(opt, dest->path, NULL,
1516 rename_branch == opt->branch1 ? dest : NULL,
1517 rename_branch == opt->branch1 ? NULL : dest);
1518 }
1519
1520 static int handle_file_collision(struct merge_options *opt,
1521 const char *collide_path,
1522 const char *prev_path1,
1523 const char *prev_path2,
1524 const char *branch1, const char *branch2,
1525 struct diff_filespec *a,
1526 struct diff_filespec *b)
1527 {
1528 struct merge_file_info mfi;
1529 struct diff_filespec null;
1530 char *alt_path = NULL;
1531 const char *update_path = collide_path;
1532
1533 /*
1534 * It's easiest to get the correct things into stage 2 and 3, and
1535 * to make sure that the content merge puts HEAD before the other
1536 * branch if we just ensure that branch1 == opt->branch1. So, simply
1537 * flip arguments around if we don't have that.
1538 */
1539 if (branch1 != opt->branch1) {
1540 return handle_file_collision(opt, collide_path,
1541 prev_path2, prev_path1,
1542 branch2, branch1,
1543 b, a);
1544 }
1545
1546 /*
1547 * In the recursive case, we just opt to undo renames
1548 */
1549 if (opt->call_depth && (prev_path1 || prev_path2)) {
1550 /* Put first file (a->oid, a->mode) in its original spot */
1551 if (prev_path1) {
1552 if (update_file(opt, 1, a, prev_path1))
1553 return -1;
1554 } else {
1555 if (update_file(opt, 1, a, collide_path))
1556 return -1;
1557 }
1558
1559 /* Put second file (b->oid, b->mode) in its original spot */
1560 if (prev_path2) {
1561 if (update_file(opt, 1, b, prev_path2))
1562 return -1;
1563 } else {
1564 if (update_file(opt, 1, b, collide_path))
1565 return -1;
1566 }
1567
1568 /* Don't leave something at collision path if unrenaming both */
1569 if (prev_path1 && prev_path2)
1570 remove_file(opt, 1, collide_path, 0);
1571
1572 return 0;
1573 }
1574
1575 /* Remove rename sources if rename/add or rename/rename(2to1) */
1576 if (prev_path1)
1577 remove_file(opt, 1, prev_path1,
1578 opt->call_depth || would_lose_untracked(opt, prev_path1));
1579 if (prev_path2)
1580 remove_file(opt, 1, prev_path2,
1581 opt->call_depth || would_lose_untracked(opt, prev_path2));
1582
1583 /*
1584 * Remove the collision path, if it wouldn't cause dirty contents
1585 * or an untracked file to get lost. We'll either overwrite with
1586 * merged contents, or just write out to differently named files.
1587 */
1588 if (was_dirty(opt, collide_path)) {
1589 output(opt, 1, _("Refusing to lose dirty file at %s"),
1590 collide_path);
1591 update_path = alt_path = unique_path(opt, collide_path, "merged");
1592 } else if (would_lose_untracked(opt, collide_path)) {
1593 /*
1594 * Only way we get here is if both renames were from
1595 * a directory rename AND user had an untracked file
1596 * at the location where both files end up after the
1597 * two directory renames. See testcase 10d of t6043.
1598 */
1599 output(opt, 1, _("Refusing to lose untracked file at "
1600 "%s, even though it's in the way."),
1601 collide_path);
1602 update_path = alt_path = unique_path(opt, collide_path, "merged");
1603 } else {
1604 /*
1605 * FIXME: It's possible that the two files are identical
1606 * and that the current working copy happens to match, in
1607 * which case we are unnecessarily touching the working
1608 * tree file. It's not a likely enough scenario that I
1609 * want to code up the checks for it and a better fix is
1610 * available if we restructure how unpack_trees() and
1611 * merge-recursive interoperate anyway, so punting for
1612 * now...
1613 */
1614 remove_file(opt, 0, collide_path, 0);
1615 }
1616
1617 /* Store things in diff_filespecs for functions that need it */
1618 null.path = (char *)collide_path;
1619 oidcpy(&null.oid, &null_oid);
1620 null.mode = 0;
1621
1622 if (merge_mode_and_contents(opt, &null, a, b, collide_path,
1623 branch1, branch2, opt->call_depth * 2, &mfi))
1624 return -1;
1625 mfi.clean &= !alt_path;
1626 if (update_file(opt, mfi.clean, &mfi.blob, update_path))
1627 return -1;
1628 if (!mfi.clean && !opt->call_depth &&
1629 update_stages(opt, collide_path, NULL, a, b))
1630 return -1;
1631 free(alt_path);
1632 /*
1633 * FIXME: If both a & b both started with conflicts (only possible
1634 * if they came from a rename/rename(2to1)), but had IDENTICAL
1635 * contents including those conflicts, then in the next line we claim
1636 * it was clean. If someone cares about this case, we should have the
1637 * caller notify us if we started with conflicts.
1638 */
1639 return mfi.clean;
1640 }
1641
1642 static int handle_rename_add(struct merge_options *opt,
1643 struct rename_conflict_info *ci)
1644 {
1645 /* a was renamed to c, and a separate c was added. */
1646 struct diff_filespec *a = ci->ren1->pair->one;
1647 struct diff_filespec *c = ci->ren1->pair->two;
1648 char *path = c->path;
1649 char *prev_path_desc;
1650 struct merge_file_info mfi;
1651
1652 const char *rename_branch = ci->ren1->branch;
1653 const char *add_branch = (opt->branch1 == rename_branch ?
1654 opt->branch2 : opt->branch1);
1655 int other_stage = (ci->ren1->branch == opt->branch1 ? 3 : 2);
1656
1657 output(opt, 1, _("CONFLICT (rename/add): "
1658 "Rename %s->%s in %s. Added %s in %s"),
1659 a->path, c->path, rename_branch,
1660 c->path, add_branch);
1661
1662 prev_path_desc = xstrfmt("version of %s from %s", path, a->path);
1663 ci->ren1->src_entry->stages[other_stage].path = a->path;
1664 if (merge_mode_and_contents(opt, a, c,
1665 &ci->ren1->src_entry->stages[other_stage],
1666 prev_path_desc,
1667 opt->branch1, opt->branch2,
1668 1 + opt->call_depth * 2, &mfi))
1669 return -1;
1670 free(prev_path_desc);
1671
1672 ci->ren1->dst_entry->stages[other_stage].path = mfi.blob.path = c->path;
1673 return handle_file_collision(opt,
1674 c->path, a->path, NULL,
1675 rename_branch, add_branch,
1676 &mfi.blob,
1677 &ci->ren1->dst_entry->stages[other_stage]);
1678 }
1679
1680 static char *find_path_for_conflict(struct merge_options *opt,
1681 const char *path,
1682 const char *branch1,
1683 const char *branch2)
1684 {
1685 char *new_path = NULL;
1686 if (dir_in_way(opt->repo->index, path, !opt->call_depth, 0)) {
1687 new_path = unique_path(opt, path, branch1);
1688 output(opt, 1, _("%s is a directory in %s adding "
1689 "as %s instead"),
1690 path, branch2, new_path);
1691 } else if (would_lose_untracked(opt, path)) {
1692 new_path = unique_path(opt, path, branch1);
1693 output(opt, 1, _("Refusing to lose untracked file"
1694 " at %s; adding as %s instead"),
1695 path, new_path);
1696 }
1697
1698 return new_path;
1699 }
1700
1701 static int handle_rename_rename_1to2(struct merge_options *opt,
1702 struct rename_conflict_info *ci)
1703 {
1704 /* One file was renamed in both branches, but to different names. */
1705 struct merge_file_info mfi;
1706 struct diff_filespec *add;
1707 struct diff_filespec *o = ci->ren1->pair->one;
1708 struct diff_filespec *a = ci->ren1->pair->two;
1709 struct diff_filespec *b = ci->ren2->pair->two;
1710 char *path_desc;
1711
1712 output(opt, 1, _("CONFLICT (rename/rename): "
1713 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1714 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1715 o->path, a->path, ci->ren1->branch,
1716 o->path, b->path, ci->ren2->branch,
1717 opt->call_depth ? _(" (left unresolved)") : "");
1718
1719 path_desc = xstrfmt("%s and %s, both renamed from %s",
1720 a->path, b->path, o->path);
1721 if (merge_mode_and_contents(opt, o, a, b, path_desc,
1722 ci->ren1->branch, ci->ren2->branch,
1723 opt->call_depth * 2, &mfi))
1724 return -1;
1725 free(path_desc);
1726
1727 if (opt->call_depth) {
1728 /*
1729 * FIXME: For rename/add-source conflicts (if we could detect
1730 * such), this is wrong. We should instead find a unique
1731 * pathname and then either rename the add-source file to that
1732 * unique path, or use that unique path instead of src here.
1733 */
1734 if (update_file(opt, 0, &mfi.blob, o->path))
1735 return -1;
1736
1737 /*
1738 * Above, we put the merged content at the merge-base's
1739 * path. Now we usually need to delete both a->path and
1740 * b->path. However, the rename on each side of the merge
1741 * could also be involved in a rename/add conflict. In
1742 * such cases, we should keep the added file around,
1743 * resolving the conflict at that path in its favor.
1744 */
1745 add = &ci->ren1->dst_entry->stages[2 ^ 1];
1746 if (is_valid(add)) {
1747 if (update_file(opt, 0, add, a->path))
1748 return -1;
1749 }
1750 else
1751 remove_file_from_index(opt->repo->index, a->path);
1752 add = &ci->ren2->dst_entry->stages[3 ^ 1];
1753 if (is_valid(add)) {
1754 if (update_file(opt, 0, add, b->path))
1755 return -1;
1756 }
1757 else
1758 remove_file_from_index(opt->repo->index, b->path);
1759 } else {
1760 /*
1761 * For each destination path, we need to see if there is a
1762 * rename/add collision. If not, we can write the file out
1763 * to the specified location.
1764 */
1765 add = &ci->ren1->dst_entry->stages[2 ^ 1];
1766 if (is_valid(add)) {
1767 add->path = mfi.blob.path = a->path;
1768 if (handle_file_collision(opt, a->path,
1769 NULL, NULL,
1770 ci->ren1->branch,
1771 ci->ren2->branch,
1772 &mfi.blob, add) < 0)
1773 return -1;
1774 } else {
1775 char *new_path = find_path_for_conflict(opt, a->path,
1776 ci->ren1->branch,
1777 ci->ren2->branch);
1778 if (update_file(opt, 0, &mfi.blob,
1779 new_path ? new_path : a->path))
1780 return -1;
1781 free(new_path);
1782 if (update_stages(opt, a->path, NULL, a, NULL))
1783 return -1;
1784 }
1785
1786 add = &ci->ren2->dst_entry->stages[3 ^ 1];
1787 if (is_valid(add)) {
1788 add->path = mfi.blob.path = b->path;
1789 if (handle_file_collision(opt, b->path,
1790 NULL, NULL,
1791 ci->ren1->branch,
1792 ci->ren2->branch,
1793 add, &mfi.blob) < 0)
1794 return -1;
1795 } else {
1796 char *new_path = find_path_for_conflict(opt, b->path,
1797 ci->ren2->branch,
1798 ci->ren1->branch);
1799 if (update_file(opt, 0, &mfi.blob,
1800 new_path ? new_path : b->path))
1801 return -1;
1802 free(new_path);
1803 if (update_stages(opt, b->path, NULL, NULL, b))
1804 return -1;
1805 }
1806 }
1807
1808 return 0;
1809 }
1810
1811 static int handle_rename_rename_2to1(struct merge_options *opt,
1812 struct rename_conflict_info *ci)
1813 {
1814 /* Two files, a & b, were renamed to the same thing, c. */
1815 struct diff_filespec *a = ci->ren1->pair->one;
1816 struct diff_filespec *b = ci->ren2->pair->one;
1817 struct diff_filespec *c1 = ci->ren1->pair->two;
1818 struct diff_filespec *c2 = ci->ren2->pair->two;
1819 char *path = c1->path; /* == c2->path */
1820 char *path_side_1_desc;
1821 char *path_side_2_desc;
1822 struct merge_file_info mfi_c1;
1823 struct merge_file_info mfi_c2;
1824 int ostage1, ostage2;
1825
1826 output(opt, 1, _("CONFLICT (rename/rename): "
1827 "Rename %s->%s in %s. "
1828 "Rename %s->%s in %s"),
1829 a->path, c1->path, ci->ren1->branch,
1830 b->path, c2->path, ci->ren2->branch);
1831
1832 path_side_1_desc = xstrfmt("version of %s from %s", path, a->path);
1833 path_side_2_desc = xstrfmt("version of %s from %s", path, b->path);
1834 ostage1 = ci->ren1->branch == opt->branch1 ? 3 : 2;
1835 ostage2 = ostage1 ^ 1;
1836 ci->ren1->src_entry->stages[ostage1].path = a->path;
1837 ci->ren2->src_entry->stages[ostage2].path = b->path;
1838 if (merge_mode_and_contents(opt, a, c1,
1839 &ci->ren1->src_entry->stages[ostage1],
1840 path_side_1_desc,
1841 opt->branch1, opt->branch2,
1842 1 + opt->call_depth * 2, &mfi_c1) ||
1843 merge_mode_and_contents(opt, b,
1844 &ci->ren2->src_entry->stages[ostage2],
1845 c2, path_side_2_desc,
1846 opt->branch1, opt->branch2,
1847 1 + opt->call_depth * 2, &mfi_c2))
1848 return -1;
1849 free(path_side_1_desc);
1850 free(path_side_2_desc);
1851 mfi_c1.blob.path = path;
1852 mfi_c2.blob.path = path;
1853
1854 return handle_file_collision(opt, path, a->path, b->path,
1855 ci->ren1->branch, ci->ren2->branch,
1856 &mfi_c1.blob, &mfi_c2.blob);
1857 }
1858
1859 /*
1860 * Get the diff_filepairs changed between o_tree and tree.
1861 */
1862 static struct diff_queue_struct *get_diffpairs(struct merge_options *opt,
1863 struct tree *o_tree,
1864 struct tree *tree)
1865 {
1866 struct diff_queue_struct *ret;
1867 struct diff_options opts;
1868
1869 repo_diff_setup(opt->repo, &opts);
1870 opts.flags.recursive = 1;
1871 opts.flags.rename_empty = 0;
1872 opts.detect_rename = merge_detect_rename(opt);
1873 /*
1874 * We do not have logic to handle the detection of copies. In
1875 * fact, it may not even make sense to add such logic: would we
1876 * really want a change to a base file to be propagated through
1877 * multiple other files by a merge?
1878 */
1879 if (opts.detect_rename > DIFF_DETECT_RENAME)
1880 opts.detect_rename = DIFF_DETECT_RENAME;
1881 opts.rename_limit = opt->merge_rename_limit >= 0 ? opt->merge_rename_limit :
1882 opt->diff_rename_limit >= 0 ? opt->diff_rename_limit :
1883 1000;
1884 opts.rename_score = opt->rename_score;
1885 opts.show_rename_progress = opt->show_rename_progress;
1886 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1887 diff_setup_done(&opts);
1888 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1889 diffcore_std(&opts);
1890 if (opts.needed_rename_limit > opt->needed_rename_limit)
1891 opt->needed_rename_limit = opts.needed_rename_limit;
1892
1893 ret = xmalloc(sizeof(*ret));
1894 *ret = diff_queued_diff;
1895
1896 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1897 diff_queued_diff.nr = 0;
1898 diff_queued_diff.queue = NULL;
1899 diff_flush(&opts);
1900 return ret;
1901 }
1902
1903 static int tree_has_path(struct tree *tree, const char *path)
1904 {
1905 struct object_id hashy;
1906 unsigned short mode_o;
1907
1908 return !get_tree_entry(&tree->object.oid, path,
1909 &hashy, &mode_o);
1910 }
1911
1912 /*
1913 * Return a new string that replaces the beginning portion (which matches
1914 * entry->dir), with entry->new_dir. In perl-speak:
1915 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1916 * NOTE:
1917 * Caller must ensure that old_path starts with entry->dir + '/'.
1918 */
1919 static char *apply_dir_rename(struct dir_rename_entry *entry,
1920 const char *old_path)
1921 {
1922 struct strbuf new_path = STRBUF_INIT;
1923 int oldlen, newlen;
1924
1925 if (entry->non_unique_new_dir)
1926 return NULL;
1927
1928 oldlen = strlen(entry->dir);
1929 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1930 strbuf_grow(&new_path, newlen);
1931 strbuf_addbuf(&new_path, &entry->new_dir);
1932 strbuf_addstr(&new_path, &old_path[oldlen]);
1933
1934 return strbuf_detach(&new_path, NULL);
1935 }
1936
1937 static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1938 char **old_dir, char **new_dir)
1939 {
1940 char *end_of_old, *end_of_new;
1941 int old_len, new_len;
1942
1943 *old_dir = NULL;
1944 *new_dir = NULL;
1945
1946 /*
1947 * For
1948 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1949 * the "e/foo.c" part is the same, we just want to know that
1950 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1951 * so, for this example, this function returns "a/b/c/d" in
1952 * *old_dir and "a/b/some/thing/else" in *new_dir.
1953 *
1954 * Also, if the basename of the file changed, we don't care. We
1955 * want to know which portion of the directory, if any, changed.
1956 */
1957 end_of_old = strrchr(old_path, '/');
1958 end_of_new = strrchr(new_path, '/');
1959
1960 if (end_of_old == NULL || end_of_new == NULL)
1961 return;
1962 while (*--end_of_new == *--end_of_old &&
1963 end_of_old != old_path &&
1964 end_of_new != new_path)
1965 ; /* Do nothing; all in the while loop */
1966 /*
1967 * We've found the first non-matching character in the directory
1968 * paths. That means the current directory we were comparing
1969 * represents the rename. Move end_of_old and end_of_new back
1970 * to the full directory name.
1971 */
1972 if (*end_of_old == '/')
1973 end_of_old++;
1974 if (*end_of_old != '/')
1975 end_of_new++;
1976 end_of_old = strchr(end_of_old, '/');
1977 end_of_new = strchr(end_of_new, '/');
1978
1979 /*
1980 * It may have been the case that old_path and new_path were the same
1981 * directory all along. Don't claim a rename if they're the same.
1982 */
1983 old_len = end_of_old - old_path;
1984 new_len = end_of_new - new_path;
1985
1986 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
1987 *old_dir = xstrndup(old_path, old_len);
1988 *new_dir = xstrndup(new_path, new_len);
1989 }
1990 }
1991
1992 static void remove_hashmap_entries(struct hashmap *dir_renames,
1993 struct string_list *items_to_remove)
1994 {
1995 int i;
1996 struct dir_rename_entry *entry;
1997
1998 for (i = 0; i < items_to_remove->nr; i++) {
1999 entry = items_to_remove->items[i].util;
2000 hashmap_remove(dir_renames, entry, NULL);
2001 }
2002 string_list_clear(items_to_remove, 0);
2003 }
2004
2005 /*
2006 * See if there is a directory rename for path, and if there are any file
2007 * level conflicts for the renamed location. If there is a rename and
2008 * there are no conflicts, return the new name. Otherwise, return NULL.
2009 */
2010 static char *handle_path_level_conflicts(struct merge_options *opt,
2011 const char *path,
2012 struct dir_rename_entry *entry,
2013 struct hashmap *collisions,
2014 struct tree *tree)
2015 {
2016 char *new_path = NULL;
2017 struct collision_entry *collision_ent;
2018 int clean = 1;
2019 struct strbuf collision_paths = STRBUF_INIT;
2020
2021 /*
2022 * entry has the mapping of old directory name to new directory name
2023 * that we want to apply to path.
2024 */
2025 new_path = apply_dir_rename(entry, path);
2026
2027 if (!new_path) {
2028 /* This should only happen when entry->non_unique_new_dir set */
2029 if (!entry->non_unique_new_dir)
2030 BUG("entry->non_unqiue_dir not set and !new_path");
2031 output(opt, 1, _("CONFLICT (directory rename split): "
2032 "Unclear where to place %s because directory "
2033 "%s was renamed to multiple other directories, "
2034 "with no destination getting a majority of the "
2035 "files."),
2036 path, entry->dir);
2037 clean = 0;
2038 return NULL;
2039 }
2040
2041 /*
2042 * The caller needs to have ensured that it has pre-populated
2043 * collisions with all paths that map to new_path. Do a quick check
2044 * to ensure that's the case.
2045 */
2046 collision_ent = collision_find_entry(collisions, new_path);
2047 if (collision_ent == NULL)
2048 BUG("collision_ent is NULL");
2049
2050 /*
2051 * Check for one-sided add/add/.../add conflicts, i.e.
2052 * where implicit renames from the other side doing
2053 * directory rename(s) can affect this side of history
2054 * to put multiple paths into the same location. Warn
2055 * and bail on directory renames for such paths.
2056 */
2057 if (collision_ent->reported_already) {
2058 clean = 0;
2059 } else if (tree_has_path(tree, new_path)) {
2060 collision_ent->reported_already = 1;
2061 strbuf_add_separated_string_list(&collision_paths, ", ",
2062 &collision_ent->source_files);
2063 output(opt, 1, _("CONFLICT (implicit dir rename): Existing "
2064 "file/dir at %s in the way of implicit "
2065 "directory rename(s) putting the following "
2066 "path(s) there: %s."),
2067 new_path, collision_paths.buf);
2068 clean = 0;
2069 } else if (collision_ent->source_files.nr > 1) {
2070 collision_ent->reported_already = 1;
2071 strbuf_add_separated_string_list(&collision_paths, ", ",
2072 &collision_ent->source_files);
2073 output(opt, 1, _("CONFLICT (implicit dir rename): Cannot map "
2074 "more than one path to %s; implicit directory "
2075 "renames tried to put these paths there: %s"),
2076 new_path, collision_paths.buf);
2077 clean = 0;
2078 }
2079
2080 /* Free memory we no longer need */
2081 strbuf_release(&collision_paths);
2082 if (!clean && new_path) {
2083 free(new_path);
2084 return NULL;
2085 }
2086
2087 return new_path;
2088 }
2089
2090 /*
2091 * There are a couple things we want to do at the directory level:
2092 * 1. Check for both sides renaming to the same thing, in order to avoid
2093 * implicit renaming of files that should be left in place. (See
2094 * testcase 6b in t6043 for details.)
2095 * 2. Prune directory renames if there are still files left in the
2096 * the original directory. These represent a partial directory rename,
2097 * i.e. a rename where only some of the files within the directory
2098 * were renamed elsewhere. (Technically, this could be done earlier
2099 * in get_directory_renames(), except that would prevent us from
2100 * doing the previous check and thus failing testcase 6b.)
2101 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
2102 * In the future, we could potentially record this info as well and
2103 * omit reporting rename/rename(1to2) conflicts for each path within
2104 * the affected directories, thus cleaning up the merge output.
2105 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
2106 * directory level, because merging directories is fine. If it
2107 * causes conflicts for files within those merged directories, then
2108 * that should be detected at the individual path level.
2109 */
2110 static void handle_directory_level_conflicts(struct merge_options *opt,
2111 struct hashmap *dir_re_head,
2112 struct tree *head,
2113 struct hashmap *dir_re_merge,
2114 struct tree *merge)
2115 {
2116 struct hashmap_iter iter;
2117 struct dir_rename_entry *head_ent;
2118 struct dir_rename_entry *merge_ent;
2119
2120 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
2121 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
2122
2123 hashmap_iter_init(dir_re_head, &iter);
2124 while ((head_ent = hashmap_iter_next(&iter))) {
2125 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
2126 if (merge_ent &&
2127 !head_ent->non_unique_new_dir &&
2128 !merge_ent->non_unique_new_dir &&
2129 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
2130 /* 1. Renamed identically; remove it from both sides */
2131 string_list_append(&remove_from_head,
2132 head_ent->dir)->util = head_ent;
2133 strbuf_release(&head_ent->new_dir);
2134 string_list_append(&remove_from_merge,
2135 merge_ent->dir)->util = merge_ent;
2136 strbuf_release(&merge_ent->new_dir);
2137 } else if (tree_has_path(head, head_ent->dir)) {
2138 /* 2. This wasn't a directory rename after all */
2139 string_list_append(&remove_from_head,
2140 head_ent->dir)->util = head_ent;
2141 strbuf_release(&head_ent->new_dir);
2142 }
2143 }
2144
2145 remove_hashmap_entries(dir_re_head, &remove_from_head);
2146 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2147
2148 hashmap_iter_init(dir_re_merge, &iter);
2149 while ((merge_ent = hashmap_iter_next(&iter))) {
2150 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
2151 if (tree_has_path(merge, merge_ent->dir)) {
2152 /* 2. This wasn't a directory rename after all */
2153 string_list_append(&remove_from_merge,
2154 merge_ent->dir)->util = merge_ent;
2155 } else if (head_ent &&
2156 !head_ent->non_unique_new_dir &&
2157 !merge_ent->non_unique_new_dir) {
2158 /* 3. rename/rename(1to2) */
2159 /*
2160 * We can assume it's not rename/rename(1to1) because
2161 * that was case (1), already checked above. So we
2162 * know that head_ent->new_dir and merge_ent->new_dir
2163 * are different strings.
2164 */
2165 output(opt, 1, _("CONFLICT (rename/rename): "
2166 "Rename directory %s->%s in %s. "
2167 "Rename directory %s->%s in %s"),
2168 head_ent->dir, head_ent->new_dir.buf, opt->branch1,
2169 head_ent->dir, merge_ent->new_dir.buf, opt->branch2);
2170 string_list_append(&remove_from_head,
2171 head_ent->dir)->util = head_ent;
2172 strbuf_release(&head_ent->new_dir);
2173 string_list_append(&remove_from_merge,
2174 merge_ent->dir)->util = merge_ent;
2175 strbuf_release(&merge_ent->new_dir);
2176 }
2177 }
2178
2179 remove_hashmap_entries(dir_re_head, &remove_from_head);
2180 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
2181 }
2182
2183 static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs)
2184 {
2185 struct hashmap *dir_renames;
2186 struct hashmap_iter iter;
2187 struct dir_rename_entry *entry;
2188 int i;
2189
2190 /*
2191 * Typically, we think of a directory rename as all files from a
2192 * certain directory being moved to a target directory. However,
2193 * what if someone first moved two files from the original
2194 * directory in one commit, and then renamed the directory
2195 * somewhere else in a later commit? At merge time, we just know
2196 * that files from the original directory went to two different
2197 * places, and that the bulk of them ended up in the same place.
2198 * We want each directory rename to represent where the bulk of the
2199 * files from that directory end up; this function exists to find
2200 * where the bulk of the files went.
2201 *
2202 * The first loop below simply iterates through the list of file
2203 * renames, finding out how often each directory rename pair
2204 * possibility occurs.
2205 */
2206 dir_renames = xmalloc(sizeof(*dir_renames));
2207 dir_rename_init(dir_renames);
2208 for (i = 0; i < pairs->nr; ++i) {
2209 struct string_list_item *item;
2210 int *count;
2211 struct diff_filepair *pair = pairs->queue[i];
2212 char *old_dir, *new_dir;
2213
2214 /* File not part of directory rename if it wasn't renamed */
2215 if (pair->status != 'R')
2216 continue;
2217
2218 get_renamed_dir_portion(pair->one->path, pair->two->path,
2219 &old_dir, &new_dir);
2220 if (!old_dir)
2221 /* Directory didn't change at all; ignore this one. */
2222 continue;
2223
2224 entry = dir_rename_find_entry(dir_renames, old_dir);
2225 if (!entry) {
2226 entry = xmalloc(sizeof(*entry));
2227 dir_rename_entry_init(entry, old_dir);
2228 hashmap_put(dir_renames, entry);
2229 } else {
2230 free(old_dir);
2231 }
2232 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
2233 if (!item) {
2234 item = string_list_insert(&entry->possible_new_dirs,
2235 new_dir);
2236 item->util = xcalloc(1, sizeof(int));
2237 } else {
2238 free(new_dir);
2239 }
2240 count = item->util;
2241 *count += 1;
2242 }
2243
2244 /*
2245 * For each directory with files moved out of it, we find out which
2246 * target directory received the most files so we can declare it to
2247 * be the "winning" target location for the directory rename. This
2248 * winner gets recorded in new_dir. If there is no winner
2249 * (multiple target directories received the same number of files),
2250 * we set non_unique_new_dir. Once we've determined the winner (or
2251 * that there is no winner), we no longer need possible_new_dirs.
2252 */
2253 hashmap_iter_init(dir_renames, &iter);
2254 while ((entry = hashmap_iter_next(&iter))) {
2255 int max = 0;
2256 int bad_max = 0;
2257 char *best = NULL;
2258
2259 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
2260 int *count = entry->possible_new_dirs.items[i].util;
2261
2262 if (*count == max)
2263 bad_max = max;
2264 else if (*count > max) {
2265 max = *count;
2266 best = entry->possible_new_dirs.items[i].string;
2267 }
2268 }
2269 if (bad_max == max)
2270 entry->non_unique_new_dir = 1;
2271 else {
2272 assert(entry->new_dir.len == 0);
2273 strbuf_addstr(&entry->new_dir, best);
2274 }
2275 /*
2276 * The relevant directory sub-portion of the original full
2277 * filepaths were xstrndup'ed before inserting into
2278 * possible_new_dirs, and instead of manually iterating the
2279 * list and free'ing each, just lie and tell
2280 * possible_new_dirs that it did the strdup'ing so that it
2281 * will free them for us.
2282 */
2283 entry->possible_new_dirs.strdup_strings = 1;
2284 string_list_clear(&entry->possible_new_dirs, 1);
2285 }
2286
2287 return dir_renames;
2288 }
2289
2290 static struct dir_rename_entry *check_dir_renamed(const char *path,
2291 struct hashmap *dir_renames)
2292 {
2293 char *temp = xstrdup(path);
2294 char *end;
2295 struct dir_rename_entry *entry = NULL;
2296
2297 while ((end = strrchr(temp, '/'))) {
2298 *end = '\0';
2299 entry = dir_rename_find_entry(dir_renames, temp);
2300 if (entry)
2301 break;
2302 }
2303 free(temp);
2304 return entry;
2305 }
2306
2307 static void compute_collisions(struct hashmap *collisions,
2308 struct hashmap *dir_renames,
2309 struct diff_queue_struct *pairs)
2310 {
2311 int i;
2312
2313 /*
2314 * Multiple files can be mapped to the same path due to directory
2315 * renames done by the other side of history. Since that other
2316 * side of history could have merged multiple directories into one,
2317 * if our side of history added the same file basename to each of
2318 * those directories, then all N of them would get implicitly
2319 * renamed by the directory rename detection into the same path,
2320 * and we'd get an add/add/.../add conflict, and all those adds
2321 * from *this* side of history. This is not representable in the
2322 * index, and users aren't going to easily be able to make sense of
2323 * it. So we need to provide a good warning about what's
2324 * happening, and fall back to no-directory-rename detection
2325 * behavior for those paths.
2326 *
2327 * See testcases 9e and all of section 5 from t6043 for examples.
2328 */
2329 collision_init(collisions);
2330
2331 for (i = 0; i < pairs->nr; ++i) {
2332 struct dir_rename_entry *dir_rename_ent;
2333 struct collision_entry *collision_ent;
2334 char *new_path;
2335 struct diff_filepair *pair = pairs->queue[i];
2336
2337 if (pair->status != 'A' && pair->status != 'R')
2338 continue;
2339 dir_rename_ent = check_dir_renamed(pair->two->path,
2340 dir_renames);
2341 if (!dir_rename_ent)
2342 continue;
2343
2344 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
2345 if (!new_path)
2346 /*
2347 * dir_rename_ent->non_unique_new_path is true, which
2348 * means there is no directory rename for us to use,
2349 * which means it won't cause us any additional
2350 * collisions.
2351 */
2352 continue;
2353 collision_ent = collision_find_entry(collisions, new_path);
2354 if (!collision_ent) {
2355 collision_ent = xcalloc(1,
2356 sizeof(struct collision_entry));
2357 hashmap_entry_init(collision_ent, strhash(new_path));
2358 hashmap_put(collisions, collision_ent);
2359 collision_ent->target_file = new_path;
2360 } else {
2361 free(new_path);
2362 }
2363 string_list_insert(&collision_ent->source_files,
2364 pair->two->path);
2365 }
2366 }
2367
2368 static char *check_for_directory_rename(struct merge_options *opt,
2369 const char *path,
2370 struct tree *tree,
2371 struct hashmap *dir_renames,
2372 struct hashmap *dir_rename_exclusions,
2373 struct hashmap *collisions,
2374 int *clean_merge)
2375 {
2376 char *new_path = NULL;
2377 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
2378 struct dir_rename_entry *oentry = NULL;
2379
2380 if (!entry)
2381 return new_path;
2382
2383 /*
2384 * This next part is a little weird. We do not want to do an
2385 * implicit rename into a directory we renamed on our side, because
2386 * that will result in a spurious rename/rename(1to2) conflict. An
2387 * example:
2388 * Base commit: dumbdir/afile, otherdir/bfile
2389 * Side 1: smrtdir/afile, otherdir/bfile
2390 * Side 2: dumbdir/afile, dumbdir/bfile
2391 * Here, while working on Side 1, we could notice that otherdir was
2392 * renamed/merged to dumbdir, and change the diff_filepair for
2393 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
2394 * 2 will notice the rename from dumbdir to smrtdir, and do the
2395 * transitive rename to move it from dumbdir/bfile to
2396 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
2397 * smrtdir, a rename/rename(1to2) conflict. We really just want
2398 * the file to end up in smrtdir. And the way to achieve that is
2399 * to not let Side1 do the rename to dumbdir, since we know that is
2400 * the source of one of our directory renames.
2401 *
2402 * That's why oentry and dir_rename_exclusions is here.
2403 *
2404 * As it turns out, this also prevents N-way transient rename
2405 * confusion; See testcases 9c and 9d of t6043.
2406 */
2407 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
2408 if (oentry) {
2409 output(opt, 1, _("WARNING: Avoiding applying %s -> %s rename "
2410 "to %s, because %s itself was renamed."),
2411 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
2412 } else {
2413 new_path = handle_path_level_conflicts(opt, path, entry,
2414 collisions, tree);
2415 *clean_merge &= (new_path != NULL);
2416 }
2417
2418 return new_path;
2419 }
2420
2421 static void apply_directory_rename_modifications(struct merge_options *opt,
2422 struct diff_filepair *pair,
2423 char *new_path,
2424 struct rename *re,
2425 struct tree *tree,
2426 struct tree *o_tree,
2427 struct tree *a_tree,
2428 struct tree *b_tree,
2429 struct string_list *entries)
2430 {
2431 struct string_list_item *item;
2432 int stage = (tree == a_tree ? 2 : 3);
2433 int update_wd;
2434
2435 /*
2436 * In all cases where we can do directory rename detection,
2437 * unpack_trees() will have read pair->two->path into the
2438 * index and the working copy. We need to remove it so that
2439 * we can instead place it at new_path. It is guaranteed to
2440 * not be untracked (unpack_trees() would have errored out
2441 * saying the file would have been overwritten), but it might
2442 * be dirty, though.
2443 */
2444 update_wd = !was_dirty(opt, pair->two->path);
2445 if (!update_wd)
2446 output(opt, 1, _("Refusing to lose dirty file at %s"),
2447 pair->two->path);
2448 remove_file(opt, 1, pair->two->path, !update_wd);
2449
2450 /* Find or create a new re->dst_entry */
2451 item = string_list_lookup(entries, new_path);
2452 if (item) {
2453 /*
2454 * Since we're renaming on this side of history, and it's
2455 * due to a directory rename on the other side of history
2456 * (which we only allow when the directory in question no
2457 * longer exists on the other side of history), the
2458 * original entry for re->dst_entry is no longer
2459 * necessary...
2460 */
2461 re->dst_entry->processed = 1;
2462
2463 /*
2464 * ...because we'll be using this new one.
2465 */
2466 re->dst_entry = item->util;
2467 } else {
2468 /*
2469 * re->dst_entry is for the before-dir-rename path, and we
2470 * need it to hold information for the after-dir-rename
2471 * path. Before creating a new entry, we need to mark the
2472 * old one as unnecessary (...unless it is shared by
2473 * src_entry, i.e. this didn't use to be a rename, in which
2474 * case we can just allow the normal processing to happen
2475 * for it).
2476 */
2477 if (pair->status == 'R')
2478 re->dst_entry->processed = 1;
2479
2480 re->dst_entry = insert_stage_data(new_path,
2481 o_tree, a_tree, b_tree,
2482 entries);
2483 item = string_list_insert(entries, new_path);
2484 item->util = re->dst_entry;
2485 }
2486
2487 /*
2488 * Update the stage_data with the information about the path we are
2489 * moving into place. That slot will be empty and available for us
2490 * to write to because of the collision checks in
2491 * handle_path_level_conflicts(). In other words,
2492 * re->dst_entry->stages[stage].oid will be the null_oid, so it's
2493 * open for us to write to.
2494 *
2495 * It may be tempting to actually update the index at this point as
2496 * well, using update_stages_for_stage_data(), but as per the big
2497 * "NOTE" in update_stages(), doing so will modify the current
2498 * in-memory index which will break calls to would_lose_untracked()
2499 * that we need to make. Instead, we need to just make sure that
2500 * the various handle_rename_*() functions update the index
2501 * explicitly rather than relying on unpack_trees() to have done it.
2502 */
2503 get_tree_entry(&tree->object.oid,
2504 pair->two->path,
2505 &re->dst_entry->stages[stage].oid,
2506 &re->dst_entry->stages[stage].mode);
2507
2508 /*
2509 * Record the original change status (or 'type' of change). If it
2510 * was originally an add ('A'), this lets us differentiate later
2511 * between a RENAME_DELETE conflict and RENAME_VIA_DIR (they
2512 * otherwise look the same). If it was originally a rename ('R'),
2513 * this lets us remember and report accurately about the transitive
2514 * renaming that occurred via the directory rename detection. Also,
2515 * record the original destination name.
2516 */
2517 re->dir_rename_original_type = pair->status;
2518 re->dir_rename_original_dest = pair->two->path;
2519
2520 /*
2521 * We don't actually look at pair->status again, but it seems
2522 * pedagogically correct to adjust it.
2523 */
2524 pair->status = 'R';
2525
2526 /*
2527 * Finally, record the new location.
2528 */
2529 pair->two->path = new_path;
2530 }
2531
2532 /*
2533 * Get information of all renames which occurred in 'pairs', making use of
2534 * any implicit directory renames inferred from the other side of history.
2535 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
2536 * to be able to associate the correct cache entries with the rename
2537 * information; tree is always equal to either a_tree or b_tree.
2538 */
2539 static struct string_list *get_renames(struct merge_options *opt,
2540 const char *branch,
2541 struct diff_queue_struct *pairs,
2542 struct hashmap *dir_renames,
2543 struct hashmap *dir_rename_exclusions,
2544 struct tree *tree,
2545 struct tree *o_tree,
2546 struct tree *a_tree,
2547 struct tree *b_tree,
2548 struct string_list *entries,
2549 int *clean_merge)
2550 {
2551 int i;
2552 struct hashmap collisions;
2553 struct hashmap_iter iter;
2554 struct collision_entry *e;
2555 struct string_list *renames;
2556
2557 compute_collisions(&collisions, dir_renames, pairs);
2558 renames = xcalloc(1, sizeof(struct string_list));
2559
2560 for (i = 0; i < pairs->nr; ++i) {
2561 struct string_list_item *item;
2562 struct rename *re;
2563 struct diff_filepair *pair = pairs->queue[i];
2564 char *new_path; /* non-NULL only with directory renames */
2565
2566 if (pair->status != 'A' && pair->status != 'R') {
2567 diff_free_filepair(pair);
2568 continue;
2569 }
2570 new_path = check_for_directory_rename(opt, pair->two->path, tree,
2571 dir_renames,
2572 dir_rename_exclusions,
2573 &collisions,
2574 clean_merge);
2575 if (pair->status != 'R' && !new_path) {
2576 diff_free_filepair(pair);
2577 continue;
2578 }
2579
2580 re = xmalloc(sizeof(*re));
2581 re->processed = 0;
2582 re->pair = pair;
2583 re->branch = branch;
2584 re->dir_rename_original_type = '\0';
2585 re->dir_rename_original_dest = NULL;
2586 item = string_list_lookup(entries, re->pair->one->path);
2587 if (!item)
2588 re->src_entry = insert_stage_data(re->pair->one->path,
2589 o_tree, a_tree, b_tree, entries);
2590 else
2591 re->src_entry = item->util;
2592
2593 item = string_list_lookup(entries, re->pair->two->path);
2594 if (!item)
2595 re->dst_entry = insert_stage_data(re->pair->two->path,
2596 o_tree, a_tree, b_tree, entries);
2597 else
2598 re->dst_entry = item->util;
2599 item = string_list_insert(renames, pair->one->path);
2600 item->util = re;
2601 if (new_path)
2602 apply_directory_rename_modifications(opt, pair, new_path,
2603 re, tree, o_tree,
2604 a_tree, b_tree,
2605 entries);
2606 }
2607
2608 hashmap_iter_init(&collisions, &iter);
2609 while ((e = hashmap_iter_next(&iter))) {
2610 free(e->target_file);
2611 string_list_clear(&e->source_files, 0);
2612 }
2613 hashmap_free(&collisions, 1);
2614 return renames;
2615 }
2616
2617 static int process_renames(struct merge_options *opt,
2618 struct string_list *a_renames,
2619 struct string_list *b_renames)
2620 {
2621 int clean_merge = 1, i, j;
2622 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2623 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2624 const struct rename *sre;
2625
2626 for (i = 0; i < a_renames->nr; i++) {
2627 sre = a_renames->items[i].util;
2628 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2629 = (void *)sre;
2630 }
2631 for (i = 0; i < b_renames->nr; i++) {
2632 sre = b_renames->items[i].util;
2633 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2634 = (void *)sre;
2635 }
2636
2637 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2638 struct string_list *renames1, *renames2Dst;
2639 struct rename *ren1 = NULL, *ren2 = NULL;
2640 const char *ren1_src, *ren1_dst;
2641 struct string_list_item *lookup;
2642
2643 if (i >= a_renames->nr) {
2644 ren2 = b_renames->items[j++].util;
2645 } else if (j >= b_renames->nr) {
2646 ren1 = a_renames->items[i++].util;
2647 } else {
2648 int compare = strcmp(a_renames->items[i].string,
2649 b_renames->items[j].string);
2650 if (compare <= 0)
2651 ren1 = a_renames->items[i++].util;
2652 if (compare >= 0)
2653 ren2 = b_renames->items[j++].util;
2654 }
2655
2656 /* TODO: refactor, so that 1/2 are not needed */
2657 if (ren1) {
2658 renames1 = a_renames;
2659 renames2Dst = &b_by_dst;
2660 } else {
2661 renames1 = b_renames;
2662 renames2Dst = &a_by_dst;
2663 SWAP(ren2, ren1);
2664 }
2665
2666 if (ren1->processed)
2667 continue;
2668 ren1->processed = 1;
2669 ren1->dst_entry->processed = 1;
2670 /* BUG: We should only mark src_entry as processed if we
2671 * are not dealing with a rename + add-source case.
2672 */
2673 ren1->src_entry->processed = 1;
2674
2675 ren1_src = ren1->pair->one->path;
2676 ren1_dst = ren1->pair->two->path;
2677
2678 if (ren2) {
2679 /* One file renamed on both sides */
2680 const char *ren2_src = ren2->pair->one->path;
2681 const char *ren2_dst = ren2->pair->two->path;
2682 enum rename_type rename_type;
2683 if (strcmp(ren1_src, ren2_src) != 0)
2684 BUG("ren1_src != ren2_src");
2685 ren2->dst_entry->processed = 1;
2686 ren2->processed = 1;
2687 if (strcmp(ren1_dst, ren2_dst) != 0) {
2688 rename_type = RENAME_ONE_FILE_TO_TWO;
2689 clean_merge = 0;
2690 } else {
2691 rename_type = RENAME_ONE_FILE_TO_ONE;
2692 /* BUG: We should only remove ren1_src in
2693 * the base stage (think of rename +
2694 * add-source cases).
2695 */
2696 remove_file(opt, 1, ren1_src, 1);
2697 update_entry(ren1->dst_entry,
2698 ren1->pair->one,
2699 ren1->pair->two,
2700 ren2->pair->two);
2701 }
2702 setup_rename_conflict_info(rename_type, opt, ren1, ren2);
2703 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2704 /* Two different files renamed to the same thing */
2705 char *ren2_dst;
2706 ren2 = lookup->util;
2707 ren2_dst = ren2->pair->two->path;
2708 if (strcmp(ren1_dst, ren2_dst) != 0)
2709 BUG("ren1_dst != ren2_dst");
2710
2711 clean_merge = 0;
2712 ren2->processed = 1;
2713 /*
2714 * BUG: We should only mark src_entry as processed
2715 * if we are not dealing with a rename + add-source
2716 * case.
2717 */
2718 ren2->src_entry->processed = 1;
2719
2720 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2721 opt, ren1, ren2);
2722 } else {
2723 /* Renamed in 1, maybe changed in 2 */
2724 /* we only use sha1 and mode of these */
2725 struct diff_filespec src_other, dst_other;
2726 int try_merge;
2727
2728 /*
2729 * unpack_trees loads entries from common-commit
2730 * into stage 1, from head-commit into stage 2, and
2731 * from merge-commit into stage 3. We keep track
2732 * of which side corresponds to the rename.
2733 */
2734 int renamed_stage = a_renames == renames1 ? 2 : 3;
2735 int other_stage = a_renames == renames1 ? 3 : 2;
2736
2737 /* BUG: We should only remove ren1_src in the base
2738 * stage and in other_stage (think of rename +
2739 * add-source case).
2740 */
2741 remove_file(opt, 1, ren1_src,
2742 renamed_stage == 2 || !was_tracked(opt, ren1_src));
2743
2744 oidcpy(&src_other.oid,
2745 &ren1->src_entry->stages[other_stage].oid);
2746 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2747 oidcpy(&dst_other.oid,
2748 &ren1->dst_entry->stages[other_stage].oid);
2749 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2750 try_merge = 0;
2751
2752 if (oid_eq(&src_other.oid, &null_oid) &&
2753 ren1->dir_rename_original_type == 'A') {
2754 setup_rename_conflict_info(RENAME_VIA_DIR,
2755 opt, ren1, NULL);
2756 } else if (oid_eq(&src_other.oid, &null_oid)) {
2757 setup_rename_conflict_info(RENAME_DELETE,
2758 opt, ren1, NULL);
2759 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2760 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2761 /*
2762 * Added file on the other side identical to
2763 * the file being renamed: clean merge.
2764 * Also, there is no need to overwrite the
2765 * file already in the working copy, so call
2766 * update_file_flags() instead of
2767 * update_file().
2768 */
2769 if (update_file_flags(opt,
2770 ren1->pair->two,
2771 ren1_dst,
2772 1, /* update_cache */
2773 0 /* update_wd */))
2774 clean_merge = -1;
2775 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2776 /*
2777 * Probably not a clean merge, but it's
2778 * premature to set clean_merge to 0 here,
2779 * because if the rename merges cleanly and
2780 * the merge exactly matches the newly added
2781 * file, then the merge will be clean.
2782 */
2783 setup_rename_conflict_info(RENAME_ADD,
2784 opt, ren1, NULL);
2785 } else
2786 try_merge = 1;
2787
2788 if (clean_merge < 0)
2789 goto cleanup_and_return;
2790 if (try_merge) {
2791 struct diff_filespec *o, *a, *b;
2792 src_other.path = (char *)ren1_src;
2793
2794 o = ren1->pair->one;
2795 if (a_renames == renames1) {
2796 a = ren1->pair->two;
2797 b = &src_other;
2798 } else {
2799 b = ren1->pair->two;
2800 a = &src_other;
2801 }
2802 update_entry(ren1->dst_entry, o, a, b);
2803 setup_rename_conflict_info(RENAME_NORMAL,
2804 opt, ren1, NULL);
2805 }
2806 }
2807 }
2808 cleanup_and_return:
2809 string_list_clear(&a_by_dst, 0);
2810 string_list_clear(&b_by_dst, 0);
2811
2812 return clean_merge;
2813 }
2814
2815 struct rename_info {
2816 struct string_list *head_renames;
2817 struct string_list *merge_renames;
2818 };
2819
2820 static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2821 struct hashmap *dir_renames)
2822 {
2823 struct hashmap_iter iter;
2824 struct dir_rename_entry *e;
2825
2826 hashmap_iter_init(dir_renames, &iter);
2827 while ((e = hashmap_iter_next(&iter))) {
2828 free(e->dir);
2829 strbuf_release(&e->new_dir);
2830 /* possible_new_dirs already cleared in get_directory_renames */
2831 }
2832 hashmap_free(dir_renames, 1);
2833 free(dir_renames);
2834
2835 free(pairs->queue);
2836 free(pairs);
2837 }
2838
2839 static int detect_and_process_renames(struct merge_options *opt,
2840 struct tree *common,
2841 struct tree *head,
2842 struct tree *merge,
2843 struct string_list *entries,
2844 struct rename_info *ri)
2845 {
2846 struct diff_queue_struct *head_pairs, *merge_pairs;
2847 struct hashmap *dir_re_head, *dir_re_merge;
2848 int clean = 1;
2849
2850 ri->head_renames = NULL;
2851 ri->merge_renames = NULL;
2852
2853 if (!merge_detect_rename(opt))
2854 return 1;
2855
2856 head_pairs = get_diffpairs(opt, common, head);
2857 merge_pairs = get_diffpairs(opt, common, merge);
2858
2859 if (opt->detect_directory_renames) {
2860 dir_re_head = get_directory_renames(head_pairs);
2861 dir_re_merge = get_directory_renames(merge_pairs);
2862
2863 handle_directory_level_conflicts(opt,
2864 dir_re_head, head,
2865 dir_re_merge, merge);
2866 } else {
2867 dir_re_head = xmalloc(sizeof(*dir_re_head));
2868 dir_re_merge = xmalloc(sizeof(*dir_re_merge));
2869 dir_rename_init(dir_re_head);
2870 dir_rename_init(dir_re_merge);
2871 }
2872
2873 ri->head_renames = get_renames(opt, opt->branch1, head_pairs,
2874 dir_re_merge, dir_re_head, head,
2875 common, head, merge, entries,
2876 &clean);
2877 if (clean < 0)
2878 goto cleanup;
2879 ri->merge_renames = get_renames(opt, opt->branch2, merge_pairs,
2880 dir_re_head, dir_re_merge, merge,
2881 common, head, merge, entries,
2882 &clean);
2883 if (clean < 0)
2884 goto cleanup;
2885 clean &= process_renames(opt, ri->head_renames, ri->merge_renames);
2886
2887 cleanup:
2888 /*
2889 * Some cleanup is deferred until cleanup_renames() because the
2890 * data structures are still needed and referenced in
2891 * process_entry(). But there are a few things we can free now.
2892 */
2893 initial_cleanup_rename(head_pairs, dir_re_head);
2894 initial_cleanup_rename(merge_pairs, dir_re_merge);
2895
2896 return clean;
2897 }
2898
2899 static void final_cleanup_rename(struct string_list *rename)
2900 {
2901 const struct rename *re;
2902 int i;
2903
2904 if (rename == NULL)
2905 return;
2906
2907 for (i = 0; i < rename->nr; i++) {
2908 re = rename->items[i].util;
2909 diff_free_filepair(re->pair);
2910 }
2911 string_list_clear(rename, 1);
2912 free(rename);
2913 }
2914
2915 static void final_cleanup_renames(struct rename_info *re_info)
2916 {
2917 final_cleanup_rename(re_info->head_renames);
2918 final_cleanup_rename(re_info->merge_renames);
2919 }
2920
2921 static int read_oid_strbuf(struct merge_options *opt,
2922 const struct object_id *oid,
2923 struct strbuf *dst)
2924 {
2925 void *buf;
2926 enum object_type type;
2927 unsigned long size;
2928 buf = read_object_file(oid, &type, &size);
2929 if (!buf)
2930 return err(opt, _("cannot read object %s"), oid_to_hex(oid));
2931 if (type != OBJ_BLOB) {
2932 free(buf);
2933 return err(opt, _("object %s is not a blob"), oid_to_hex(oid));
2934 }
2935 strbuf_attach(dst, buf, size, size + 1);
2936 return 0;
2937 }
2938
2939 static int blob_unchanged(struct merge_options *opt,
2940 const struct diff_filespec *o,
2941 const struct diff_filespec *a,
2942 int renormalize, const char *path)
2943 {
2944 struct strbuf obuf = STRBUF_INIT;
2945 struct strbuf abuf = STRBUF_INIT;
2946 int ret = 0; /* assume changed for safety */
2947 const struct index_state *idx = opt->repo->index;
2948
2949 if (a->mode != o->mode)
2950 return 0;
2951 if (oid_eq(&o->oid, &a->oid))
2952 return 1;
2953 if (!renormalize)
2954 return 0;
2955
2956 if (read_oid_strbuf(opt, &o->oid, &obuf) ||
2957 read_oid_strbuf(opt, &a->oid, &abuf))
2958 goto error_return;
2959 /*
2960 * Note: binary | is used so that both renormalizations are
2961 * performed. Comparison can be skipped if both files are
2962 * unchanged since their sha1s have already been compared.
2963 */
2964 if (renormalize_buffer(idx, path, obuf.buf, obuf.len, &obuf) |
2965 renormalize_buffer(idx, path, abuf.buf, abuf.len, &abuf))
2966 ret = (obuf.len == abuf.len && !memcmp(obuf.buf, abuf.buf, obuf.len));
2967
2968 error_return:
2969 strbuf_release(&obuf);
2970 strbuf_release(&abuf);
2971 return ret;
2972 }
2973
2974 static int handle_modify_delete(struct merge_options *opt,
2975 const char *path,
2976 const struct diff_filespec *o,
2977 const struct diff_filespec *a,
2978 const struct diff_filespec *b)
2979 {
2980 const char *modify_branch, *delete_branch;
2981 const struct diff_filespec *changed;
2982
2983 if (is_valid(a)) {
2984 modify_branch = opt->branch1;
2985 delete_branch = opt->branch2;
2986 changed = a;
2987 } else {
2988 modify_branch = opt->branch2;
2989 delete_branch = opt->branch1;
2990 changed = b;
2991 }
2992
2993 return handle_change_delete(opt,
2994 path, NULL,
2995 o, changed,
2996 modify_branch, delete_branch,
2997 _("modify"), _("modified"));
2998 }
2999
3000 static int handle_content_merge(struct merge_file_info *mfi,
3001 struct merge_options *opt,
3002 const char *path,
3003 int is_dirty,
3004 const struct diff_filespec *o,
3005 const struct diff_filespec *a,
3006 const struct diff_filespec *b,
3007 struct rename_conflict_info *ci)
3008 {
3009 const char *reason = _("content");
3010 unsigned df_conflict_remains = 0;
3011
3012 if (!is_valid(o))
3013 reason = _("add/add");
3014
3015 assert(o->path && a->path && b->path);
3016 if (ci && dir_in_way(opt->repo->index, path, !opt->call_depth,
3017 S_ISGITLINK(ci->ren1->pair->two->mode)))
3018 df_conflict_remains = 1;
3019
3020 if (merge_mode_and_contents(opt, o, a, b, path,
3021 opt->branch1, opt->branch2,
3022 opt->call_depth * 2, mfi))
3023 return -1;
3024
3025 /*
3026 * We can skip updating the working tree file iff:
3027 * a) The merge is clean
3028 * b) The merge matches what was in HEAD (content, mode, pathname)
3029 * c) The target path is usable (i.e. not involved in D/F conflict)
3030 */
3031 if (mfi->clean && was_tracked_and_matches(opt, path, &mfi->blob) &&
3032 !df_conflict_remains) {
3033 int pos;
3034 struct cache_entry *ce;
3035
3036 output(opt, 3, _("Skipped %s (merged same as existing)"), path);
3037 if (add_cacheinfo(opt, &mfi->blob, path,
3038 0, (!opt->call_depth && !is_dirty), 0))
3039 return -1;
3040 /*
3041 * However, add_cacheinfo() will delete the old cache entry
3042 * and add a new one. We need to copy over any skip_worktree
3043 * flag to avoid making the file appear as if it were
3044 * deleted by the user.
3045 */
3046 pos = index_name_pos(&opt->orig_index, path, strlen(path));
3047 ce = opt->orig_index.cache[pos];
3048 if (ce_skip_worktree(ce)) {
3049 pos = index_name_pos(opt->repo->index, path, strlen(path));
3050 ce = opt->repo->index->cache[pos];
3051 ce->ce_flags |= CE_SKIP_WORKTREE;
3052 }
3053 return mfi->clean;
3054 }
3055
3056 if (!mfi->clean) {
3057 if (S_ISGITLINK(mfi->blob.mode))
3058 reason = _("submodule");
3059 output(opt, 1, _("CONFLICT (%s): Merge conflict in %s"),
3060 reason, path);
3061 if (ci && !df_conflict_remains)
3062 if (update_stages(opt, path, o, a, b))
3063 return -1;
3064 }
3065
3066 if (df_conflict_remains || is_dirty) {
3067 char *new_path;
3068 if (opt->call_depth) {
3069 remove_file_from_index(opt->repo->index, path);
3070 } else {
3071 if (!mfi->clean) {
3072 if (update_stages(opt, path, o, a, b))
3073 return -1;
3074 } else {
3075 int file_from_stage2 = was_tracked(opt, path);
3076
3077 if (update_stages(opt, path, NULL,
3078 file_from_stage2 ? &mfi->blob : NULL,
3079 file_from_stage2 ? NULL : &mfi->blob))
3080 return -1;
3081 }
3082
3083 }
3084 new_path = unique_path(opt, path, ci->ren1->branch);
3085 if (is_dirty) {
3086 output(opt, 1, _("Refusing to lose dirty file at %s"),
3087 path);
3088 }
3089 output(opt, 1, _("Adding as %s instead"), new_path);
3090 if (update_file(opt, 0, &mfi->blob, new_path)) {
3091 free(new_path);
3092 return -1;
3093 }
3094 free(new_path);
3095 mfi->clean = 0;
3096 } else if (update_file(opt, mfi->clean, &mfi->blob, path))
3097 return -1;
3098 return !is_dirty && mfi->clean;
3099 }
3100
3101 static int handle_rename_normal(struct merge_options *opt,
3102 const char *path,
3103 const struct diff_filespec *o,
3104 const struct diff_filespec *a,
3105 const struct diff_filespec *b,
3106 struct rename_conflict_info *ci)
3107 {
3108 struct rename *ren = ci->ren1;
3109 struct merge_file_info mfi;
3110 int clean;
3111 int side = (ren->branch == opt->branch1 ? 2 : 3);
3112
3113 /* Merge the content and write it out */
3114 clean = handle_content_merge(&mfi, opt, path, was_dirty(opt, path),
3115 o, a, b, ci);
3116
3117 if (clean && opt->detect_directory_renames == 1 &&
3118 ren->dir_rename_original_dest) {
3119 if (update_stages(opt, path,
3120 NULL,
3121 side == 2 ? &mfi.blob : NULL,
3122 side == 2 ? NULL : &mfi.blob))
3123 return -1;
3124 clean = 0; /* not clean, but conflicted */
3125 }
3126 return clean;
3127 }
3128
3129 static void dir_rename_warning(const char *msg,
3130 int is_add,
3131 int clean,
3132 struct merge_options *opt,
3133 struct rename *ren)
3134 {
3135 const char *other_branch;
3136 other_branch = (ren->branch == opt->branch1 ?
3137 opt->branch2 : opt->branch1);
3138 if (is_add) {
3139 output(opt, clean ? 2 : 1, msg,
3140 ren->pair->one->path, ren->branch,
3141 other_branch, ren->pair->two->path);
3142 return;
3143 }
3144 output(opt, clean ? 2 : 1, msg,
3145 ren->pair->one->path, ren->dir_rename_original_dest, ren->branch,
3146 other_branch, ren->pair->two->path);
3147 }
3148 static int warn_about_dir_renamed_entries(struct merge_options *opt,
3149 struct rename *ren)
3150 {
3151 const char *msg;
3152 int clean = 1, is_add;
3153
3154 if (!ren)
3155 return clean;
3156
3157 /* Return early if ren was not affected/created by a directory rename */
3158 if (!ren->dir_rename_original_dest)
3159 return clean;
3160
3161 /* Sanity checks */
3162 assert(opt->detect_directory_renames > 0);
3163 assert(ren->dir_rename_original_type == 'A' ||
3164 ren->dir_rename_original_type == 'R');
3165
3166 /* Check whether to treat directory renames as a conflict */
3167 clean = (opt->detect_directory_renames == 2);
3168
3169 is_add = (ren->dir_rename_original_type == 'A');
3170 if (ren->dir_rename_original_type == 'A' && clean) {
3171 msg = _("Path updated: %s added in %s inside a "
3172 "directory that was renamed in %s; moving it to %s.");
3173 } else if (ren->dir_rename_original_type == 'A' && !clean) {
3174 msg = _("CONFLICT (file location): %s added in %s "
3175 "inside a directory that was renamed in %s, "
3176 "suggesting it should perhaps be moved to %s.");
3177 } else if (ren->dir_rename_original_type == 'R' && clean) {
3178 msg = _("Path updated: %s renamed to %s in %s, inside a "
3179 "directory that was renamed in %s; moving it to %s.");
3180 } else if (ren->dir_rename_original_type == 'R' && !clean) {
3181 msg = _("CONFLICT (file location): %s renamed to %s in %s, "
3182 "inside a directory that was renamed in %s, "
3183 "suggesting it should perhaps be moved to %s.");
3184 } else {
3185 BUG("Impossible dir_rename_original_type/clean combination");
3186 }
3187 dir_rename_warning(msg, is_add, clean, opt, ren);
3188
3189 return clean;
3190 }
3191
3192 /* Per entry merge function */
3193 static int process_entry(struct merge_options *opt,
3194 const char *path, struct stage_data *entry)
3195 {
3196 int clean_merge = 1;
3197 int normalize = opt->renormalize;
3198
3199 struct diff_filespec *o = &entry->stages[1];
3200 struct diff_filespec *a = &entry->stages[2];
3201 struct diff_filespec *b = &entry->stages[3];
3202 int o_valid = is_valid(o);
3203 int a_valid = is_valid(a);
3204 int b_valid = is_valid(b);
3205 o->path = a->path = b->path = (char*)path;
3206
3207 entry->processed = 1;
3208 if (entry->rename_conflict_info) {
3209 struct rename_conflict_info *ci = entry->rename_conflict_info;
3210 struct diff_filespec *temp;
3211 int path_clean;
3212
3213 path_clean = warn_about_dir_renamed_entries(opt, ci->ren1);
3214 path_clean &= warn_about_dir_renamed_entries(opt, ci->ren2);
3215
3216 /*
3217 * For cases with a single rename, {o,a,b}->path have all been
3218 * set to the rename target path; we need to set two of these
3219 * back to the rename source.
3220 * For rename/rename conflicts, we'll manually fix paths below.
3221 */
3222 temp = (opt->branch1 == ci->ren1->branch) ? b : a;
3223 o->path = temp->path = ci->ren1->pair->one->path;
3224 if (ci->ren2) {
3225 assert(opt->branch1 == ci->ren1->branch);
3226 }
3227
3228 switch (ci->rename_type) {
3229 case RENAME_NORMAL:
3230 case RENAME_ONE_FILE_TO_ONE:
3231 clean_merge = handle_rename_normal(opt, path, o, a, b,
3232 ci);
3233 break;
3234 case RENAME_VIA_DIR:
3235 clean_merge = handle_rename_via_dir(opt, ci);
3236 break;
3237 case RENAME_ADD:
3238 /*
3239 * Probably unclean merge, but if the renamed file
3240 * merges cleanly and the result can then be
3241 * two-way merged cleanly with the added file, I
3242 * guess it's a clean merge?
3243 */
3244 clean_merge = handle_rename_add(opt, ci);
3245 break;
3246 case RENAME_DELETE:
3247 clean_merge = 0;
3248 if (handle_rename_delete(opt, ci))
3249 clean_merge = -1;
3250 break;
3251 case RENAME_ONE_FILE_TO_TWO:
3252 /*
3253 * Manually fix up paths; note:
3254 * ren[12]->pair->one->path are equal.
3255 */
3256 o->path = ci->ren1->pair->one->path;
3257 a->path = ci->ren1->pair->two->path;
3258 b->path = ci->ren2->pair->two->path;
3259
3260 clean_merge = 0;
3261 if (handle_rename_rename_1to2(opt, ci))
3262 clean_merge = -1;
3263 break;
3264 case RENAME_TWO_FILES_TO_ONE:
3265 /*
3266 * Manually fix up paths; note,
3267 * ren[12]->pair->two->path are actually equal.
3268 */
3269 o->path = NULL;
3270 a->path = ci->ren1->pair->two->path;
3271 b->path = ci->ren2->pair->two->path;
3272
3273 /*
3274 * Probably unclean merge, but if the two renamed
3275 * files merge cleanly and the two resulting files
3276 * can then be two-way merged cleanly, I guess it's
3277 * a clean merge?
3278 */
3279 clean_merge = handle_rename_rename_2to1(opt, ci);
3280 break;
3281 default:
3282 entry->processed = 0;
3283 break;
3284 }
3285 if (path_clean < clean_merge)
3286 clean_merge = path_clean;
3287 } else if (o_valid && (!a_valid || !b_valid)) {
3288 /* Case A: Deleted in one */
3289 if ((!a_valid && !b_valid) ||
3290 (!b_valid && blob_unchanged(opt, o, a, normalize, path)) ||
3291 (!a_valid && blob_unchanged(opt, o, b, normalize, path))) {
3292 /* Deleted in both or deleted in one and
3293 * unchanged in the other */
3294 if (a_valid)
3295 output(opt, 2, _("Removing %s"), path);
3296 /* do not touch working file if it did not exist */
3297 remove_file(opt, 1, path, !a_valid);
3298 } else {
3299 /* Modify/delete; deleted side may have put a directory in the way */
3300 clean_merge = 0;
3301 if (handle_modify_delete(opt, path, o, a, b))
3302 clean_merge = -1;
3303 }
3304 } else if ((!o_valid && a_valid && !b_valid) ||
3305 (!o_valid && !a_valid && b_valid)) {
3306 /* Case B: Added in one. */
3307 /* [nothing|directory] -> ([nothing|directory], file) */
3308
3309 const char *add_branch;
3310 const char *other_branch;
3311 const char *conf;
3312 const struct diff_filespec *contents;
3313
3314 if (a_valid) {
3315 add_branch = opt->branch1;
3316 other_branch = opt->branch2;
3317 contents = a;
3318 conf = _("file/directory");
3319 } else {
3320 add_branch = opt->branch2;
3321 other_branch = opt->branch1;
3322 contents = b;
3323 conf = _("directory/file");
3324 }
3325 if (dir_in_way(opt->repo->index, path,
3326 !opt->call_depth && !S_ISGITLINK(a->mode),
3327 0)) {
3328 char *new_path = unique_path(opt, path, add_branch);
3329 clean_merge = 0;
3330 output(opt, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
3331 "Adding %s as %s"),
3332 conf, path, other_branch, path, new_path);
3333 if (update_file(opt, 0, contents, new_path))
3334 clean_merge = -1;
3335 else if (opt->call_depth)
3336 remove_file_from_index(opt->repo->index, path);
3337 free(new_path);
3338 } else {
3339 output(opt, 2, _("Adding %s"), path);
3340 /* do not overwrite file if already present */
3341 if (update_file_flags(opt, contents, path, 1, !a_valid))
3342 clean_merge = -1;
3343 }
3344 } else if (a_valid && b_valid) {
3345 if (!o_valid) {
3346 /* Case C: Added in both (check for same permissions) */
3347 output(opt, 1,
3348 _("CONFLICT (add/add): Merge conflict in %s"),
3349 path);
3350 clean_merge = handle_file_collision(opt,
3351 path, NULL, NULL,
3352 opt->branch1,
3353 opt->branch2,
3354 a, b);
3355 } else {
3356 /* case D: Modified in both, but differently. */
3357 struct merge_file_info mfi;
3358 int is_dirty = 0; /* unpack_trees would have bailed if dirty */
3359 clean_merge = handle_content_merge(&mfi, opt, path,
3360 is_dirty,
3361 o, a, b, NULL);
3362 }
3363 } else if (!o_valid && !a_valid && !b_valid) {
3364 /*
3365 * this entry was deleted altogether. a_mode == 0 means
3366 * we had that path and want to actively remove it.
3367 */
3368 remove_file(opt, 1, path, !a->mode);
3369 } else
3370 BUG("fatal merge failure, shouldn't happen.");
3371
3372 return clean_merge;
3373 }
3374
3375 int merge_trees(struct merge_options *opt,
3376 struct tree *head,
3377 struct tree *merge,
3378 struct tree *common,
3379 struct tree **result)
3380 {
3381 struct index_state *istate = opt->repo->index;
3382 int code, clean;
3383 struct strbuf sb = STRBUF_INIT;
3384
3385 if (!opt->call_depth && repo_index_has_changes(opt->repo, head, &sb)) {
3386 err(opt, _("Your local changes to the following files would be overwritten by merge:\n %s"),
3387 sb.buf);
3388 return -1;
3389 }
3390
3391 if (opt->subtree_shift) {
3392 merge = shift_tree_object(opt->repo, head, merge, opt->subtree_shift);
3393 common = shift_tree_object(opt->repo, head, common, opt->subtree_shift);
3394 }
3395
3396 if (oid_eq(&common->object.oid, &merge->object.oid)) {
3397 output(opt, 0, _("Already up to date!"));
3398 *result = head;
3399 return 1;
3400 }
3401
3402 code = unpack_trees_start(opt, common, head, merge);
3403
3404 if (code != 0) {
3405 if (show(opt, 4) || opt->call_depth)
3406 err(opt, _("merging of trees %s and %s failed"),
3407 oid_to_hex(&head->object.oid),
3408 oid_to_hex(&merge->object.oid));
3409 unpack_trees_finish(opt);
3410 return -1;
3411 }
3412
3413 if (unmerged_index(istate)) {
3414 struct string_list *entries;
3415 struct rename_info re_info;
3416 int i;
3417 /*
3418 * Only need the hashmap while processing entries, so
3419 * initialize it here and free it when we are done running
3420 * through the entries. Keeping it in the merge_options as
3421 * opposed to decaring a local hashmap is for convenience
3422 * so that we don't have to pass it to around.
3423 */
3424 hashmap_init(&opt->current_file_dir_set, path_hashmap_cmp, NULL, 512);
3425 get_files_dirs(opt, head);
3426 get_files_dirs(opt, merge);
3427
3428 entries = get_unmerged(opt->repo->index);
3429 clean = detect_and_process_renames(opt, common, head, merge,
3430 entries, &re_info);
3431 record_df_conflict_files(opt, entries);
3432 if (clean < 0)
3433 goto cleanup;
3434 for (i = entries->nr-1; 0 <= i; i--) {
3435 const char *path = entries->items[i].string;
3436 struct stage_data *e = entries->items[i].util;
3437 if (!e->processed) {
3438 int ret = process_entry(opt, path, e);
3439 if (!ret)
3440 clean = 0;
3441 else if (ret < 0) {
3442 clean = ret;
3443 goto cleanup;
3444 }
3445 }
3446 }
3447 for (i = 0; i < entries->nr; i++) {
3448 struct stage_data *e = entries->items[i].util;
3449 if (!e->processed)
3450 BUG("unprocessed path??? %s",
3451 entries->items[i].string);
3452 }
3453
3454 cleanup:
3455 final_cleanup_renames(&re_info);
3456
3457 string_list_clear(entries, 1);
3458 free(entries);
3459
3460 hashmap_free(&opt->current_file_dir_set, 1);
3461
3462 if (clean < 0) {
3463 unpack_trees_finish(opt);
3464 return clean;
3465 }
3466 }
3467 else
3468 clean = 1;
3469
3470 unpack_trees_finish(opt);
3471
3472 if (opt->call_depth && !(*result = write_tree_from_memory(opt)))
3473 return -1;
3474
3475 return clean;
3476 }
3477
3478 static struct commit_list *reverse_commit_list(struct commit_list *list)
3479 {
3480 struct commit_list *next = NULL, *current, *backup;
3481 for (current = list; current; current = backup) {
3482 backup = current->next;
3483 current->next = next;
3484 next = current;
3485 }
3486 return next;
3487 }
3488
3489 /*
3490 * Merge the commits h1 and h2, return the resulting virtual
3491 * commit object and a flag indicating the cleanness of the merge.
3492 */
3493 int merge_recursive(struct merge_options *opt,
3494 struct commit *h1,
3495 struct commit *h2,
3496 struct commit_list *ca,
3497 struct commit **result)
3498 {
3499 struct commit_list *iter;
3500 struct commit *merged_common_ancestors;
3501 struct tree *mrtree;
3502 int clean;
3503
3504 if (show(opt, 4)) {
3505 output(opt, 4, _("Merging:"));
3506 output_commit_title(opt, h1);
3507 output_commit_title(opt, h2);
3508 }
3509
3510 if (!ca) {
3511 ca = get_merge_bases(h1, h2);
3512 ca = reverse_commit_list(ca);
3513 }
3514
3515 if (show(opt, 5)) {
3516 unsigned cnt = commit_list_count(ca);
3517
3518 output(opt, 5, Q_("found %u common ancestor:",
3519 "found %u common ancestors:", cnt), cnt);
3520 for (iter = ca; iter; iter = iter->next)
3521 output_commit_title(opt, iter->item);
3522 }
3523
3524 merged_common_ancestors = pop_commit(&ca);
3525 if (merged_common_ancestors == NULL) {
3526 /* if there is no common ancestor, use an empty tree */
3527 struct tree *tree;
3528
3529 tree = lookup_tree(opt->repo, opt->repo->hash_algo->empty_tree);
3530 merged_common_ancestors = make_virtual_commit(opt->repo, tree, "ancestor");
3531 }
3532
3533 for (iter = ca; iter; iter = iter->next) {
3534 const char *saved_b1, *saved_b2;
3535 opt->call_depth++;
3536 /*
3537 * When the merge fails, the result contains files
3538 * with conflict markers. The cleanness flag is
3539 * ignored (unless indicating an error), it was never
3540 * actually used, as result of merge_trees has always
3541 * overwritten it: the committed "conflicts" were
3542 * already resolved.
3543 */
3544 discard_index(opt->repo->index);
3545 saved_b1 = opt->branch1;
3546 saved_b2 = opt->branch2;
3547 opt->branch1 = "Temporary merge branch 1";
3548 opt->branch2 = "Temporary merge branch 2";
3549 if (merge_recursive(opt, merged_common_ancestors, iter->item,
3550 NULL, &merged_common_ancestors) < 0)
3551 return -1;
3552 opt->branch1 = saved_b1;
3553 opt->branch2 = saved_b2;
3554 opt->call_depth--;
3555
3556 if (!merged_common_ancestors)
3557 return err(opt, _("merge returned no commit"));
3558 }
3559
3560 discard_index(opt->repo->index);
3561 if (!opt->call_depth)
3562 repo_read_index(opt->repo);
3563
3564 opt->ancestor = "merged common ancestors";
3565 clean = merge_trees(opt, get_commit_tree(h1), get_commit_tree(h2),
3566 get_commit_tree(merged_common_ancestors),
3567 &mrtree);
3568 if (clean < 0) {
3569 flush_output(opt);
3570 return clean;
3571 }
3572
3573 if (opt->call_depth) {
3574 *result = make_virtual_commit(opt->repo, mrtree, "merged tree");
3575 commit_list_insert(h1, &(*result)->parents);
3576 commit_list_insert(h2, &(*result)->parents->next);
3577 }
3578 flush_output(opt);
3579 if (!opt->call_depth && opt->buffer_output < 2)
3580 strbuf_release(&opt->obuf);
3581 if (show(opt, 2))
3582 diff_warn_rename_limit("merge.renamelimit",
3583 opt->needed_rename_limit, 0);
3584 return clean;
3585 }
3586
3587 static struct commit *get_ref(struct repository *repo, const struct object_id *oid,
3588 const char *name)
3589 {
3590 struct object *object;
3591
3592 object = deref_tag(repo, parse_object(repo, oid),
3593 name, strlen(name));
3594 if (!object)
3595 return NULL;
3596 if (object->type == OBJ_TREE)
3597 return make_virtual_commit(repo, (struct tree*)object, name);
3598 if (object->type != OBJ_COMMIT)
3599 return NULL;
3600 if (parse_commit((struct commit *)object))
3601 return NULL;
3602 return (struct commit *)object;
3603 }
3604