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