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