Merge branch 'en/merge-recursive-fixes'
[git/git.git] / merge-recursive.c
1 /*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6 #include "cache.h"
7 #include "config.h"
8 #include "advice.h"
9 #include "lockfile.h"
10 #include "cache-tree.h"
11 #include "commit.h"
12 #include "blob.h"
13 #include "builtin.h"
14 #include "tree-walk.h"
15 #include "diff.h"
16 #include "diffcore.h"
17 #include "tag.h"
18 #include "unpack-trees.h"
19 #include "string-list.h"
20 #include "xdiff-interface.h"
21 #include "ll-merge.h"
22 #include "attr.h"
23 #include "merge-recursive.h"
24 #include "dir.h"
25 #include "submodule.h"
26
27 struct path_hashmap_entry {
28 struct hashmap_entry e;
29 char path[FLEX_ARRAY];
30 };
31
32 static int path_hashmap_cmp(const void *cmp_data,
33 const void *entry,
34 const void *entry_or_key,
35 const void *keydata)
36 {
37 const struct path_hashmap_entry *a = entry;
38 const struct path_hashmap_entry *b = entry_or_key;
39 const char *key = keydata;
40
41 if (ignore_case)
42 return strcasecmp(a->path, key ? key : b->path);
43 else
44 return strcmp(a->path, key ? key : b->path);
45 }
46
47 static unsigned int path_hash(const char *path)
48 {
49 return ignore_case ? strihash(path) : strhash(path);
50 }
51
52 static void flush_output(struct merge_options *o)
53 {
54 if (o->buffer_output < 2 && o->obuf.len) {
55 fputs(o->obuf.buf, stdout);
56 strbuf_reset(&o->obuf);
57 }
58 }
59
60 static int err(struct merge_options *o, const char *err, ...)
61 {
62 va_list params;
63
64 if (o->buffer_output < 2)
65 flush_output(o);
66 else {
67 strbuf_complete(&o->obuf, '\n');
68 strbuf_addstr(&o->obuf, "error: ");
69 }
70 va_start(params, err);
71 strbuf_vaddf(&o->obuf, err, params);
72 va_end(params);
73 if (o->buffer_output > 1)
74 strbuf_addch(&o->obuf, '\n');
75 else {
76 error("%s", o->obuf.buf);
77 strbuf_reset(&o->obuf);
78 }
79
80 return -1;
81 }
82
83 static struct tree *shift_tree_object(struct tree *one, struct tree *two,
84 const char *subtree_shift)
85 {
86 struct object_id shifted;
87
88 if (!*subtree_shift) {
89 shift_tree(&one->object.oid, &two->object.oid, &shifted, 0);
90 } else {
91 shift_tree_by(&one->object.oid, &two->object.oid, &shifted,
92 subtree_shift);
93 }
94 if (!oidcmp(&two->object.oid, &shifted))
95 return two;
96 return lookup_tree(&shifted);
97 }
98
99 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
100 {
101 struct commit *commit = alloc_commit_node();
102
103 set_merge_remote_desc(commit, comment, (struct object *)commit);
104 commit->tree = tree;
105 commit->object.parsed = 1;
106 return commit;
107 }
108
109 /*
110 * Since we use get_tree_entry(), which does not put the read object into
111 * the object pool, we cannot rely on a == b.
112 */
113 static int oid_eq(const struct object_id *a, const struct object_id *b)
114 {
115 if (!a && !b)
116 return 2;
117 return a && b && oidcmp(a, b) == 0;
118 }
119
120 enum rename_type {
121 RENAME_NORMAL = 0,
122 RENAME_DELETE,
123 RENAME_ONE_FILE_TO_ONE,
124 RENAME_ONE_FILE_TO_TWO,
125 RENAME_TWO_FILES_TO_ONE
126 };
127
128 struct rename_conflict_info {
129 enum rename_type rename_type;
130 struct diff_filepair *pair1;
131 struct diff_filepair *pair2;
132 const char *branch1;
133 const char *branch2;
134 struct stage_data *dst_entry1;
135 struct stage_data *dst_entry2;
136 struct diff_filespec ren1_other;
137 struct diff_filespec ren2_other;
138 };
139
140 /*
141 * Since we want to write the index eventually, we cannot reuse the index
142 * for these (temporary) data.
143 */
144 struct stage_data {
145 struct {
146 unsigned mode;
147 struct object_id oid;
148 } stages[4];
149 struct rename_conflict_info *rename_conflict_info;
150 unsigned processed:1;
151 };
152
153 static inline void setup_rename_conflict_info(enum rename_type rename_type,
154 struct diff_filepair *pair1,
155 struct diff_filepair *pair2,
156 const char *branch1,
157 const char *branch2,
158 struct stage_data *dst_entry1,
159 struct stage_data *dst_entry2,
160 struct merge_options *o,
161 struct stage_data *src_entry1,
162 struct stage_data *src_entry2)
163 {
164 struct rename_conflict_info *ci = xcalloc(1, sizeof(struct rename_conflict_info));
165 ci->rename_type = rename_type;
166 ci->pair1 = pair1;
167 ci->branch1 = branch1;
168 ci->branch2 = branch2;
169
170 ci->dst_entry1 = dst_entry1;
171 dst_entry1->rename_conflict_info = ci;
172 dst_entry1->processed = 0;
173
174 assert(!pair2 == !dst_entry2);
175 if (dst_entry2) {
176 ci->dst_entry2 = dst_entry2;
177 ci->pair2 = pair2;
178 dst_entry2->rename_conflict_info = ci;
179 }
180
181 if (rename_type == RENAME_TWO_FILES_TO_ONE) {
182 /*
183 * For each rename, there could have been
184 * modifications on the side of history where that
185 * file was not renamed.
186 */
187 int ostage1 = o->branch1 == branch1 ? 3 : 2;
188 int ostage2 = ostage1 ^ 1;
189
190 ci->ren1_other.path = pair1->one->path;
191 oidcpy(&ci->ren1_other.oid, &src_entry1->stages[ostage1].oid);
192 ci->ren1_other.mode = src_entry1->stages[ostage1].mode;
193
194 ci->ren2_other.path = pair2->one->path;
195 oidcpy(&ci->ren2_other.oid, &src_entry2->stages[ostage2].oid);
196 ci->ren2_other.mode = src_entry2->stages[ostage2].mode;
197 }
198 }
199
200 static int show(struct merge_options *o, int v)
201 {
202 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
203 }
204
205 __attribute__((format (printf, 3, 4)))
206 static void output(struct merge_options *o, int v, const char *fmt, ...)
207 {
208 va_list ap;
209
210 if (!show(o, v))
211 return;
212
213 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
214
215 va_start(ap, fmt);
216 strbuf_vaddf(&o->obuf, fmt, ap);
217 va_end(ap);
218
219 strbuf_addch(&o->obuf, '\n');
220 if (!o->buffer_output)
221 flush_output(o);
222 }
223
224 static void output_commit_title(struct merge_options *o, struct commit *commit)
225 {
226 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
227 if (commit->util)
228 strbuf_addf(&o->obuf, "virtual %s\n",
229 merge_remote_util(commit)->name);
230 else {
231 strbuf_add_unique_abbrev(&o->obuf, commit->object.oid.hash,
232 DEFAULT_ABBREV);
233 strbuf_addch(&o->obuf, ' ');
234 if (parse_commit(commit) != 0)
235 strbuf_addstr(&o->obuf, _("(bad commit)\n"));
236 else {
237 const char *title;
238 const char *msg = get_commit_buffer(commit, NULL);
239 int len = find_commit_subject(msg, &title);
240 if (len)
241 strbuf_addf(&o->obuf, "%.*s\n", len, title);
242 unuse_commit_buffer(commit, msg);
243 }
244 }
245 flush_output(o);
246 }
247
248 static int add_cacheinfo(struct merge_options *o,
249 unsigned int mode, const struct object_id *oid,
250 const char *path, int stage, int refresh, int options)
251 {
252 struct cache_entry *ce;
253 int ret;
254
255 ce = make_cache_entry(mode, oid ? oid->hash : null_sha1, path, stage, 0);
256 if (!ce)
257 return err(o, _("addinfo_cache failed for path '%s'"), path);
258
259 ret = add_cache_entry(ce, options);
260 if (refresh) {
261 struct cache_entry *nce;
262
263 nce = refresh_cache_entry(ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
264 if (!nce)
265 return err(o, _("addinfo_cache failed for path '%s'"), path);
266 if (nce != ce)
267 ret = add_cache_entry(nce, options);
268 }
269 return ret;
270 }
271
272 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
273 {
274 parse_tree(tree);
275 init_tree_desc(desc, tree->buffer, tree->size);
276 }
277
278 static int git_merge_trees(int index_only,
279 struct tree *common,
280 struct tree *head,
281 struct tree *merge)
282 {
283 int rc;
284 struct tree_desc t[3];
285 struct unpack_trees_options opts;
286
287 memset(&opts, 0, sizeof(opts));
288 if (index_only)
289 opts.index_only = 1;
290 else
291 opts.update = 1;
292 opts.merge = 1;
293 opts.head_idx = 2;
294 opts.fn = threeway_merge;
295 opts.src_index = &the_index;
296 opts.dst_index = &the_index;
297 setup_unpack_trees_porcelain(&opts, "merge");
298
299 init_tree_desc_from_tree(t+0, common);
300 init_tree_desc_from_tree(t+1, head);
301 init_tree_desc_from_tree(t+2, merge);
302
303 rc = unpack_trees(3, t, &opts);
304 cache_tree_free(&active_cache_tree);
305 return rc;
306 }
307
308 struct tree *write_tree_from_memory(struct merge_options *o)
309 {
310 struct tree *result = NULL;
311
312 if (unmerged_cache()) {
313 int i;
314 fprintf(stderr, "BUG: There are unmerged index entries:\n");
315 for (i = 0; i < active_nr; i++) {
316 const struct cache_entry *ce = active_cache[i];
317 if (ce_stage(ce))
318 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
319 (int)ce_namelen(ce), ce->name);
320 }
321 die("BUG: unmerged index entries in merge-recursive.c");
322 }
323
324 if (!active_cache_tree)
325 active_cache_tree = cache_tree();
326
327 if (!cache_tree_fully_valid(active_cache_tree) &&
328 cache_tree_update(&the_index, 0) < 0) {
329 err(o, _("error building trees"));
330 return NULL;
331 }
332
333 result = lookup_tree(&active_cache_tree->oid);
334
335 return result;
336 }
337
338 static int save_files_dirs(const unsigned char *sha1,
339 struct strbuf *base, const char *path,
340 unsigned int mode, int stage, void *context)
341 {
342 struct path_hashmap_entry *entry;
343 int baselen = base->len;
344 struct merge_options *o = context;
345
346 strbuf_addstr(base, path);
347
348 FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
349 hashmap_entry_init(entry, path_hash(entry->path));
350 hashmap_add(&o->current_file_dir_set, entry);
351
352 strbuf_setlen(base, baselen);
353 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
354 }
355
356 static void get_files_dirs(struct merge_options *o, struct tree *tree)
357 {
358 struct pathspec match_all;
359 memset(&match_all, 0, sizeof(match_all));
360 read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
361 }
362
363 /*
364 * Returns an index_entry instance which doesn't have to correspond to
365 * a real cache entry in Git's index.
366 */
367 static struct stage_data *insert_stage_data(const char *path,
368 struct tree *o, struct tree *a, struct tree *b,
369 struct string_list *entries)
370 {
371 struct string_list_item *item;
372 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
373 get_tree_entry(o->object.oid.hash, path,
374 e->stages[1].oid.hash, &e->stages[1].mode);
375 get_tree_entry(a->object.oid.hash, path,
376 e->stages[2].oid.hash, &e->stages[2].mode);
377 get_tree_entry(b->object.oid.hash, path,
378 e->stages[3].oid.hash, &e->stages[3].mode);
379 item = string_list_insert(entries, path);
380 item->util = e;
381 return e;
382 }
383
384 /*
385 * Create a dictionary mapping file names to stage_data objects. The
386 * dictionary contains one entry for every path with a non-zero stage entry.
387 */
388 static struct string_list *get_unmerged(void)
389 {
390 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
391 int i;
392
393 unmerged->strdup_strings = 1;
394
395 for (i = 0; i < active_nr; i++) {
396 struct string_list_item *item;
397 struct stage_data *e;
398 const struct cache_entry *ce = active_cache[i];
399 if (!ce_stage(ce))
400 continue;
401
402 item = string_list_lookup(unmerged, ce->name);
403 if (!item) {
404 item = string_list_insert(unmerged, ce->name);
405 item->util = xcalloc(1, sizeof(struct stage_data));
406 }
407 e = item->util;
408 e->stages[ce_stage(ce)].mode = ce->ce_mode;
409 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
410 }
411
412 return unmerged;
413 }
414
415 static int string_list_df_name_compare(const char *one, const char *two)
416 {
417 int onelen = strlen(one);
418 int twolen = strlen(two);
419 /*
420 * Here we only care that entries for D/F conflicts are
421 * adjacent, in particular with the file of the D/F conflict
422 * appearing before files below the corresponding directory.
423 * The order of the rest of the list is irrelevant for us.
424 *
425 * To achieve this, we sort with df_name_compare and provide
426 * the mode S_IFDIR so that D/F conflicts will sort correctly.
427 * We use the mode S_IFDIR for everything else for simplicity,
428 * since in other cases any changes in their order due to
429 * sorting cause no problems for us.
430 */
431 int cmp = df_name_compare(one, onelen, S_IFDIR,
432 two, twolen, S_IFDIR);
433 /*
434 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
435 * that 'foo' comes before 'foo/bar'.
436 */
437 if (cmp)
438 return cmp;
439 return onelen - twolen;
440 }
441
442 static void record_df_conflict_files(struct merge_options *o,
443 struct string_list *entries)
444 {
445 /* If there is a D/F conflict and the file for such a conflict
446 * currently exist in the working tree, we want to allow it to be
447 * removed to make room for the corresponding directory if needed.
448 * The files underneath the directories of such D/F conflicts will
449 * be processed before the corresponding file involved in the D/F
450 * conflict. If the D/F directory ends up being removed by the
451 * merge, then we won't have to touch the D/F file. If the D/F
452 * directory needs to be written to the working copy, then the D/F
453 * file will simply be removed (in make_room_for_path()) to make
454 * room for the necessary paths. Note that if both the directory
455 * and the file need to be present, then the D/F file will be
456 * reinstated with a new unique name at the time it is processed.
457 */
458 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
459 const char *last_file = NULL;
460 int last_len = 0;
461 int i;
462
463 /*
464 * If we're merging merge-bases, we don't want to bother with
465 * any working directory changes.
466 */
467 if (o->call_depth)
468 return;
469
470 /* Ensure D/F conflicts are adjacent in the entries list. */
471 for (i = 0; i < entries->nr; i++) {
472 struct string_list_item *next = &entries->items[i];
473 string_list_append(&df_sorted_entries, next->string)->util =
474 next->util;
475 }
476 df_sorted_entries.cmp = string_list_df_name_compare;
477 string_list_sort(&df_sorted_entries);
478
479 string_list_clear(&o->df_conflict_file_set, 1);
480 for (i = 0; i < df_sorted_entries.nr; i++) {
481 const char *path = df_sorted_entries.items[i].string;
482 int len = strlen(path);
483 struct stage_data *e = df_sorted_entries.items[i].util;
484
485 /*
486 * Check if last_file & path correspond to a D/F conflict;
487 * i.e. whether path is last_file+'/'+<something>.
488 * If so, record that it's okay to remove last_file to make
489 * room for path and friends if needed.
490 */
491 if (last_file &&
492 len > last_len &&
493 memcmp(path, last_file, last_len) == 0 &&
494 path[last_len] == '/') {
495 string_list_insert(&o->df_conflict_file_set, last_file);
496 }
497
498 /*
499 * Determine whether path could exist as a file in the
500 * working directory as a possible D/F conflict. This
501 * will only occur when it exists in stage 2 as a
502 * file.
503 */
504 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
505 last_file = path;
506 last_len = len;
507 } else {
508 last_file = NULL;
509 }
510 }
511 string_list_clear(&df_sorted_entries, 0);
512 }
513
514 struct rename {
515 struct diff_filepair *pair;
516 /*
517 * Purpose of src_entry and dst_entry:
518 *
519 * If 'before' is renamed to 'after' then src_entry will contain
520 * the versions of 'before' from the merge_base, HEAD, and MERGE in
521 * stages 1, 2, and 3; dst_entry will contain the respective
522 * versions of 'after' in corresponding locations. Thus, we have a
523 * total of six modes and oids, though some will be null. (Stage 0
524 * is ignored; we're interested in handling conflicts.)
525 *
526 * Since we don't turn on break-rewrites by default, neither
527 * src_entry nor dst_entry can have all three of their stages have
528 * non-null oids, meaning at most four of the six will be non-null.
529 * Also, since this is a rename, both src_entry and dst_entry will
530 * have at least one non-null oid, meaning at least two will be
531 * non-null. Of the six oids, a typical rename will have three be
532 * non-null. Only two implies a rename/delete, and four implies a
533 * rename/add.
534 */
535 struct stage_data *src_entry;
536 struct stage_data *dst_entry;
537 unsigned processed:1;
538 };
539
540 /*
541 * Get information of all renames which occurred between 'o_tree' and
542 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
543 * 'b_tree') to be able to associate the correct cache entries with
544 * the rename information. 'tree' is always equal to either a_tree or b_tree.
545 */
546 static struct string_list *get_renames(struct merge_options *o,
547 struct tree *tree,
548 struct tree *o_tree,
549 struct tree *a_tree,
550 struct tree *b_tree,
551 struct string_list *entries)
552 {
553 int i;
554 struct string_list *renames;
555 struct diff_options opts;
556
557 renames = xcalloc(1, sizeof(struct string_list));
558 if (!o->detect_rename)
559 return renames;
560
561 diff_setup(&opts);
562 opts.flags.recursive = 1;
563 opts.flags.rename_empty = 0;
564 opts.detect_rename = DIFF_DETECT_RENAME;
565 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
566 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
567 1000;
568 opts.rename_score = o->rename_score;
569 opts.show_rename_progress = o->show_rename_progress;
570 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
571 diff_setup_done(&opts);
572 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
573 diffcore_std(&opts);
574 if (opts.needed_rename_limit > o->needed_rename_limit)
575 o->needed_rename_limit = opts.needed_rename_limit;
576 for (i = 0; i < diff_queued_diff.nr; ++i) {
577 struct string_list_item *item;
578 struct rename *re;
579 struct diff_filepair *pair = diff_queued_diff.queue[i];
580 if (pair->status != 'R') {
581 diff_free_filepair(pair);
582 continue;
583 }
584 re = xmalloc(sizeof(*re));
585 re->processed = 0;
586 re->pair = pair;
587 item = string_list_lookup(entries, re->pair->one->path);
588 if (!item)
589 re->src_entry = insert_stage_data(re->pair->one->path,
590 o_tree, a_tree, b_tree, entries);
591 else
592 re->src_entry = item->util;
593
594 item = string_list_lookup(entries, re->pair->two->path);
595 if (!item)
596 re->dst_entry = insert_stage_data(re->pair->two->path,
597 o_tree, a_tree, b_tree, entries);
598 else
599 re->dst_entry = item->util;
600 item = string_list_insert(renames, pair->one->path);
601 item->util = re;
602 }
603 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
604 diff_queued_diff.nr = 0;
605 diff_flush(&opts);
606 return renames;
607 }
608
609 static int update_stages(struct merge_options *opt, const char *path,
610 const struct diff_filespec *o,
611 const struct diff_filespec *a,
612 const struct diff_filespec *b)
613 {
614
615 /*
616 * NOTE: It is usually a bad idea to call update_stages on a path
617 * before calling update_file on that same path, since it can
618 * sometimes lead to spurious "refusing to lose untracked file..."
619 * messages from update_file (via make_room_for path via
620 * would_lose_untracked). Instead, reverse the order of the calls
621 * (executing update_file first and then update_stages).
622 */
623 int clear = 1;
624 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
625 if (clear)
626 if (remove_file_from_cache(path))
627 return -1;
628 if (o)
629 if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options))
630 return -1;
631 if (a)
632 if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options))
633 return -1;
634 if (b)
635 if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options))
636 return -1;
637 return 0;
638 }
639
640 static void update_entry(struct stage_data *entry,
641 struct diff_filespec *o,
642 struct diff_filespec *a,
643 struct diff_filespec *b)
644 {
645 entry->processed = 0;
646 entry->stages[1].mode = o->mode;
647 entry->stages[2].mode = a->mode;
648 entry->stages[3].mode = b->mode;
649 oidcpy(&entry->stages[1].oid, &o->oid);
650 oidcpy(&entry->stages[2].oid, &a->oid);
651 oidcpy(&entry->stages[3].oid, &b->oid);
652 }
653
654 static int remove_file(struct merge_options *o, int clean,
655 const char *path, int no_wd)
656 {
657 int update_cache = o->call_depth || clean;
658 int update_working_directory = !o->call_depth && !no_wd;
659
660 if (update_cache) {
661 if (remove_file_from_cache(path))
662 return -1;
663 }
664 if (update_working_directory) {
665 if (ignore_case) {
666 struct cache_entry *ce;
667 ce = cache_file_exists(path, strlen(path), ignore_case);
668 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
669 return 0;
670 }
671 if (remove_path(path))
672 return -1;
673 }
674 return 0;
675 }
676
677 /* add a string to a strbuf, but converting "/" to "_" */
678 static void add_flattened_path(struct strbuf *out, const char *s)
679 {
680 size_t i = out->len;
681 strbuf_addstr(out, s);
682 for (; i < out->len; i++)
683 if (out->buf[i] == '/')
684 out->buf[i] = '_';
685 }
686
687 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
688 {
689 struct path_hashmap_entry *entry;
690 struct strbuf newpath = STRBUF_INIT;
691 int suffix = 0;
692 size_t base_len;
693
694 strbuf_addf(&newpath, "%s~", path);
695 add_flattened_path(&newpath, branch);
696
697 base_len = newpath.len;
698 while (hashmap_get_from_hash(&o->current_file_dir_set,
699 path_hash(newpath.buf), newpath.buf) ||
700 (!o->call_depth && file_exists(newpath.buf))) {
701 strbuf_setlen(&newpath, base_len);
702 strbuf_addf(&newpath, "_%d", suffix++);
703 }
704
705 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
706 hashmap_entry_init(entry, path_hash(entry->path));
707 hashmap_add(&o->current_file_dir_set, entry);
708 return strbuf_detach(&newpath, NULL);
709 }
710
711 /**
712 * Check whether a directory in the index is in the way of an incoming
713 * file. Return 1 if so. If check_working_copy is non-zero, also
714 * check the working directory. If empty_ok is non-zero, also return
715 * 0 in the case where the working-tree dir exists but is empty.
716 */
717 static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
718 {
719 int pos;
720 struct strbuf dirpath = STRBUF_INIT;
721 struct stat st;
722
723 strbuf_addstr(&dirpath, path);
724 strbuf_addch(&dirpath, '/');
725
726 pos = cache_name_pos(dirpath.buf, dirpath.len);
727
728 if (pos < 0)
729 pos = -1 - pos;
730 if (pos < active_nr &&
731 !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) {
732 strbuf_release(&dirpath);
733 return 1;
734 }
735
736 strbuf_release(&dirpath);
737 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
738 !(empty_ok && is_empty_dir(path));
739 }
740
741 static int was_tracked(const char *path)
742 {
743 int pos = cache_name_pos(path, strlen(path));
744
745 if (0 <= pos)
746 /* we have been tracking this path */
747 return 1;
748
749 /*
750 * Look for an unmerged entry for the path,
751 * specifically stage #2, which would indicate
752 * that "our" side before the merge started
753 * had the path tracked (and resulted in a conflict).
754 */
755 for (pos = -1 - pos;
756 pos < active_nr && !strcmp(path, active_cache[pos]->name);
757 pos++)
758 if (ce_stage(active_cache[pos]) == 2)
759 return 1;
760 return 0;
761 }
762
763 static int would_lose_untracked(const char *path)
764 {
765 return !was_tracked(path) && file_exists(path);
766 }
767
768 static int make_room_for_path(struct merge_options *o, const char *path)
769 {
770 int status, i;
771 const char *msg = _("failed to create path '%s'%s");
772
773 /* Unlink any D/F conflict files that are in the way */
774 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
775 const char *df_path = o->df_conflict_file_set.items[i].string;
776 size_t pathlen = strlen(path);
777 size_t df_pathlen = strlen(df_path);
778 if (df_pathlen < pathlen &&
779 path[df_pathlen] == '/' &&
780 strncmp(path, df_path, df_pathlen) == 0) {
781 output(o, 3,
782 _("Removing %s to make room for subdirectory\n"),
783 df_path);
784 unlink(df_path);
785 unsorted_string_list_delete_item(&o->df_conflict_file_set,
786 i, 0);
787 break;
788 }
789 }
790
791 /* Make sure leading directories are created */
792 status = safe_create_leading_directories_const(path);
793 if (status) {
794 if (status == SCLD_EXISTS)
795 /* something else exists */
796 return err(o, msg, path, _(": perhaps a D/F conflict?"));
797 return err(o, msg, path, "");
798 }
799
800 /*
801 * Do not unlink a file in the work tree if we are not
802 * tracking it.
803 */
804 if (would_lose_untracked(path))
805 return err(o, _("refusing to lose untracked file at '%s'"),
806 path);
807
808 /* Successful unlink is good.. */
809 if (!unlink(path))
810 return 0;
811 /* .. and so is no existing file */
812 if (errno == ENOENT)
813 return 0;
814 /* .. but not some other error (who really cares what?) */
815 return err(o, msg, path, _(": perhaps a D/F conflict?"));
816 }
817
818 static int update_file_flags(struct merge_options *o,
819 const struct object_id *oid,
820 unsigned mode,
821 const char *path,
822 int update_cache,
823 int update_wd)
824 {
825 int ret = 0;
826
827 if (o->call_depth)
828 update_wd = 0;
829
830 if (update_wd) {
831 enum object_type type;
832 void *buf;
833 unsigned long size;
834
835 if (S_ISGITLINK(mode)) {
836 /*
837 * We may later decide to recursively descend into
838 * the submodule directory and update its index
839 * and/or work tree, but we do not do that now.
840 */
841 update_wd = 0;
842 goto update_index;
843 }
844
845 buf = read_sha1_file(oid->hash, &type, &size);
846 if (!buf)
847 return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path);
848 if (type != OBJ_BLOB) {
849 ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path);
850 goto free_buf;
851 }
852 if (S_ISREG(mode)) {
853 struct strbuf strbuf = STRBUF_INIT;
854 if (convert_to_working_tree(path, buf, size, &strbuf)) {
855 free(buf);
856 size = strbuf.len;
857 buf = strbuf_detach(&strbuf, NULL);
858 }
859 }
860
861 if (make_room_for_path(o, path) < 0) {
862 update_wd = 0;
863 goto free_buf;
864 }
865 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
866 int fd;
867 if (mode & 0100)
868 mode = 0777;
869 else
870 mode = 0666;
871 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
872 if (fd < 0) {
873 ret = err(o, _("failed to open '%s': %s"),
874 path, strerror(errno));
875 goto free_buf;
876 }
877 write_in_full(fd, buf, size);
878 close(fd);
879 } else if (S_ISLNK(mode)) {
880 char *lnk = xmemdupz(buf, size);
881 safe_create_leading_directories_const(path);
882 unlink(path);
883 if (symlink(lnk, path))
884 ret = err(o, _("failed to symlink '%s': %s"),
885 path, strerror(errno));
886 free(lnk);
887 } else
888 ret = err(o,
889 _("do not know what to do with %06o %s '%s'"),
890 mode, oid_to_hex(oid), path);
891 free_buf:
892 free(buf);
893 }
894 update_index:
895 if (!ret && update_cache)
896 add_cacheinfo(o, mode, oid, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
897 return ret;
898 }
899
900 static int update_file(struct merge_options *o,
901 int clean,
902 const struct object_id *oid,
903 unsigned mode,
904 const char *path)
905 {
906 return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth);
907 }
908
909 /* Low level file merging, update and removal */
910
911 struct merge_file_info {
912 struct object_id oid;
913 unsigned mode;
914 unsigned clean:1,
915 merge:1;
916 };
917
918 static int merge_3way(struct merge_options *o,
919 mmbuffer_t *result_buf,
920 const struct diff_filespec *one,
921 const struct diff_filespec *a,
922 const struct diff_filespec *b,
923 const char *branch1,
924 const char *branch2)
925 {
926 mmfile_t orig, src1, src2;
927 struct ll_merge_options ll_opts = {0};
928 char *base_name, *name1, *name2;
929 int merge_status;
930
931 ll_opts.renormalize = o->renormalize;
932 ll_opts.xdl_opts = o->xdl_opts;
933
934 if (o->call_depth) {
935 ll_opts.virtual_ancestor = 1;
936 ll_opts.variant = 0;
937 } else {
938 switch (o->recursive_variant) {
939 case MERGE_RECURSIVE_OURS:
940 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
941 break;
942 case MERGE_RECURSIVE_THEIRS:
943 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
944 break;
945 default:
946 ll_opts.variant = 0;
947 break;
948 }
949 }
950
951 if (strcmp(a->path, b->path) ||
952 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
953 base_name = o->ancestor == NULL ? NULL :
954 mkpathdup("%s:%s", o->ancestor, one->path);
955 name1 = mkpathdup("%s:%s", branch1, a->path);
956 name2 = mkpathdup("%s:%s", branch2, b->path);
957 } else {
958 base_name = o->ancestor == NULL ? NULL :
959 mkpathdup("%s", o->ancestor);
960 name1 = mkpathdup("%s", branch1);
961 name2 = mkpathdup("%s", branch2);
962 }
963
964 read_mmblob(&orig, &one->oid);
965 read_mmblob(&src1, &a->oid);
966 read_mmblob(&src2, &b->oid);
967
968 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
969 &src1, name1, &src2, name2, &ll_opts);
970
971 free(base_name);
972 free(name1);
973 free(name2);
974 free(orig.ptr);
975 free(src1.ptr);
976 free(src2.ptr);
977 return merge_status;
978 }
979
980 static int merge_file_1(struct merge_options *o,
981 const struct diff_filespec *one,
982 const struct diff_filespec *a,
983 const struct diff_filespec *b,
984 const char *branch1,
985 const char *branch2,
986 struct merge_file_info *result)
987 {
988 result->merge = 0;
989 result->clean = 1;
990
991 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
992 result->clean = 0;
993 if (S_ISREG(a->mode)) {
994 result->mode = a->mode;
995 oidcpy(&result->oid, &a->oid);
996 } else {
997 result->mode = b->mode;
998 oidcpy(&result->oid, &b->oid);
999 }
1000 } else {
1001 if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid))
1002 result->merge = 1;
1003
1004 /*
1005 * Merge modes
1006 */
1007 if (a->mode == b->mode || a->mode == one->mode)
1008 result->mode = b->mode;
1009 else {
1010 result->mode = a->mode;
1011 if (b->mode != one->mode) {
1012 result->clean = 0;
1013 result->merge = 1;
1014 }
1015 }
1016
1017 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid))
1018 oidcpy(&result->oid, &b->oid);
1019 else if (oid_eq(&b->oid, &one->oid))
1020 oidcpy(&result->oid, &a->oid);
1021 else if (S_ISREG(a->mode)) {
1022 mmbuffer_t result_buf;
1023 int ret = 0, merge_status;
1024
1025 merge_status = merge_3way(o, &result_buf, one, a, b,
1026 branch1, branch2);
1027
1028 if ((merge_status < 0) || !result_buf.ptr)
1029 ret = err(o, _("Failed to execute internal merge"));
1030
1031 if (!ret && write_sha1_file(result_buf.ptr, result_buf.size,
1032 blob_type, result->oid.hash))
1033 ret = err(o, _("Unable to add %s to database"),
1034 a->path);
1035
1036 free(result_buf.ptr);
1037 if (ret)
1038 return ret;
1039 result->clean = (merge_status == 0);
1040 } else if (S_ISGITLINK(a->mode)) {
1041 result->clean = merge_submodule(&result->oid,
1042 one->path,
1043 &one->oid,
1044 &a->oid,
1045 &b->oid,
1046 !o->call_depth);
1047 } else if (S_ISLNK(a->mode)) {
1048 switch (o->recursive_variant) {
1049 case MERGE_RECURSIVE_NORMAL:
1050 oidcpy(&result->oid, &a->oid);
1051 if (!oid_eq(&a->oid, &b->oid))
1052 result->clean = 0;
1053 break;
1054 case MERGE_RECURSIVE_OURS:
1055 oidcpy(&result->oid, &a->oid);
1056 break;
1057 case MERGE_RECURSIVE_THEIRS:
1058 oidcpy(&result->oid, &b->oid);
1059 break;
1060 }
1061 } else
1062 die("BUG: unsupported object type in the tree");
1063 }
1064
1065 return 0;
1066 }
1067
1068 static int merge_file_special_markers(struct merge_options *o,
1069 const struct diff_filespec *one,
1070 const struct diff_filespec *a,
1071 const struct diff_filespec *b,
1072 const char *branch1,
1073 const char *filename1,
1074 const char *branch2,
1075 const char *filename2,
1076 struct merge_file_info *mfi)
1077 {
1078 char *side1 = NULL;
1079 char *side2 = NULL;
1080 int ret;
1081
1082 if (filename1)
1083 side1 = xstrfmt("%s:%s", branch1, filename1);
1084 if (filename2)
1085 side2 = xstrfmt("%s:%s", branch2, filename2);
1086
1087 ret = merge_file_1(o, one, a, b,
1088 side1 ? side1 : branch1,
1089 side2 ? side2 : branch2, mfi);
1090 free(side1);
1091 free(side2);
1092 return ret;
1093 }
1094
1095 static int merge_file_one(struct merge_options *o,
1096 const char *path,
1097 const struct object_id *o_oid, int o_mode,
1098 const struct object_id *a_oid, int a_mode,
1099 const struct object_id *b_oid, int b_mode,
1100 const char *branch1,
1101 const char *branch2,
1102 struct merge_file_info *mfi)
1103 {
1104 struct diff_filespec one, a, b;
1105
1106 one.path = a.path = b.path = (char *)path;
1107 oidcpy(&one.oid, o_oid);
1108 one.mode = o_mode;
1109 oidcpy(&a.oid, a_oid);
1110 a.mode = a_mode;
1111 oidcpy(&b.oid, b_oid);
1112 b.mode = b_mode;
1113 return merge_file_1(o, &one, &a, &b, branch1, branch2, mfi);
1114 }
1115
1116 static int handle_change_delete(struct merge_options *o,
1117 const char *path, const char *old_path,
1118 const struct object_id *o_oid, int o_mode,
1119 const struct object_id *changed_oid,
1120 int changed_mode,
1121 const char *change_branch,
1122 const char *delete_branch,
1123 const char *change, const char *change_past)
1124 {
1125 char *alt_path = NULL;
1126 const char *update_path = path;
1127 int ret = 0;
1128
1129 if (dir_in_way(path, !o->call_depth, 0)) {
1130 update_path = alt_path = unique_path(o, path, change_branch);
1131 }
1132
1133 if (o->call_depth) {
1134 /*
1135 * We cannot arbitrarily accept either a_sha or b_sha as
1136 * correct; since there is no true "middle point" between
1137 * them, simply reuse the base version for virtual merge base.
1138 */
1139 ret = remove_file_from_cache(path);
1140 if (!ret)
1141 ret = update_file(o, 0, o_oid, o_mode, update_path);
1142 } else {
1143 if (!alt_path) {
1144 if (!old_path) {
1145 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1146 "and %s in %s. Version %s of %s left in tree."),
1147 change, path, delete_branch, change_past,
1148 change_branch, change_branch, path);
1149 } else {
1150 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1151 "and %s to %s in %s. Version %s of %s left in tree."),
1152 change, old_path, delete_branch, change_past, path,
1153 change_branch, change_branch, path);
1154 }
1155 } else {
1156 if (!old_path) {
1157 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1158 "and %s in %s. Version %s of %s left in tree at %s."),
1159 change, path, delete_branch, change_past,
1160 change_branch, change_branch, path, alt_path);
1161 } else {
1162 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1163 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1164 change, old_path, delete_branch, change_past, path,
1165 change_branch, change_branch, path, alt_path);
1166 }
1167 }
1168 /*
1169 * No need to call update_file() on path when change_branch ==
1170 * o->branch1 && !alt_path, since that would needlessly touch
1171 * path. We could call update_file_flags() with update_cache=0
1172 * and update_wd=0, but that's a no-op.
1173 */
1174 if (change_branch != o->branch1 || alt_path)
1175 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1176 }
1177 free(alt_path);
1178
1179 return ret;
1180 }
1181
1182 static int conflict_rename_delete(struct merge_options *o,
1183 struct diff_filepair *pair,
1184 const char *rename_branch,
1185 const char *delete_branch)
1186 {
1187 const struct diff_filespec *orig = pair->one;
1188 const struct diff_filespec *dest = pair->two;
1189
1190 if (handle_change_delete(o,
1191 o->call_depth ? orig->path : dest->path,
1192 o->call_depth ? NULL : orig->path,
1193 &orig->oid, orig->mode,
1194 &dest->oid, dest->mode,
1195 rename_branch, delete_branch,
1196 _("rename"), _("renamed")))
1197 return -1;
1198
1199 if (o->call_depth)
1200 return remove_file_from_cache(dest->path);
1201 else
1202 return update_stages(o, dest->path, NULL,
1203 rename_branch == o->branch1 ? dest : NULL,
1204 rename_branch == o->branch1 ? NULL : dest);
1205 }
1206
1207 static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1208 struct stage_data *entry,
1209 int stage)
1210 {
1211 struct object_id *oid = &entry->stages[stage].oid;
1212 unsigned mode = entry->stages[stage].mode;
1213 if (mode == 0 || is_null_oid(oid))
1214 return NULL;
1215 oidcpy(&target->oid, oid);
1216 target->mode = mode;
1217 return target;
1218 }
1219
1220 static int handle_file(struct merge_options *o,
1221 struct diff_filespec *rename,
1222 int stage,
1223 struct rename_conflict_info *ci)
1224 {
1225 char *dst_name = rename->path;
1226 struct stage_data *dst_entry;
1227 const char *cur_branch, *other_branch;
1228 struct diff_filespec other;
1229 struct diff_filespec *add;
1230 int ret;
1231
1232 if (stage == 2) {
1233 dst_entry = ci->dst_entry1;
1234 cur_branch = ci->branch1;
1235 other_branch = ci->branch2;
1236 } else {
1237 dst_entry = ci->dst_entry2;
1238 cur_branch = ci->branch2;
1239 other_branch = ci->branch1;
1240 }
1241
1242 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1243 if (add) {
1244 char *add_name = unique_path(o, rename->path, other_branch);
1245 if (update_file(o, 0, &add->oid, add->mode, add_name))
1246 return -1;
1247
1248 remove_file(o, 0, rename->path, 0);
1249 dst_name = unique_path(o, rename->path, cur_branch);
1250 } else {
1251 if (dir_in_way(rename->path, !o->call_depth, 0)) {
1252 dst_name = unique_path(o, rename->path, cur_branch);
1253 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1254 rename->path, other_branch, dst_name);
1255 }
1256 }
1257 if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name)))
1258 ; /* fall through, do allow dst_name to be released */
1259 else if (stage == 2)
1260 ret = update_stages(o, rename->path, NULL, rename, add);
1261 else
1262 ret = update_stages(o, rename->path, NULL, add, rename);
1263
1264 if (dst_name != rename->path)
1265 free(dst_name);
1266
1267 return ret;
1268 }
1269
1270 static int conflict_rename_rename_1to2(struct merge_options *o,
1271 struct rename_conflict_info *ci)
1272 {
1273 /* One file was renamed in both branches, but to different names. */
1274 struct diff_filespec *one = ci->pair1->one;
1275 struct diff_filespec *a = ci->pair1->two;
1276 struct diff_filespec *b = ci->pair2->two;
1277
1278 output(o, 1, _("CONFLICT (rename/rename): "
1279 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1280 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1281 one->path, a->path, ci->branch1,
1282 one->path, b->path, ci->branch2,
1283 o->call_depth ? _(" (left unresolved)") : "");
1284 if (o->call_depth) {
1285 struct merge_file_info mfi;
1286 struct diff_filespec other;
1287 struct diff_filespec *add;
1288 if (merge_file_one(o, one->path,
1289 &one->oid, one->mode,
1290 &a->oid, a->mode,
1291 &b->oid, b->mode,
1292 ci->branch1, ci->branch2, &mfi))
1293 return -1;
1294
1295 /*
1296 * FIXME: For rename/add-source conflicts (if we could detect
1297 * such), this is wrong. We should instead find a unique
1298 * pathname and then either rename the add-source file to that
1299 * unique path, or use that unique path instead of src here.
1300 */
1301 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1302 return -1;
1303
1304 /*
1305 * Above, we put the merged content at the merge-base's
1306 * path. Now we usually need to delete both a->path and
1307 * b->path. However, the rename on each side of the merge
1308 * could also be involved in a rename/add conflict. In
1309 * such cases, we should keep the added file around,
1310 * resolving the conflict at that path in its favor.
1311 */
1312 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1313 if (add) {
1314 if (update_file(o, 0, &add->oid, add->mode, a->path))
1315 return -1;
1316 }
1317 else
1318 remove_file_from_cache(a->path);
1319 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1320 if (add) {
1321 if (update_file(o, 0, &add->oid, add->mode, b->path))
1322 return -1;
1323 }
1324 else
1325 remove_file_from_cache(b->path);
1326 } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci))
1327 return -1;
1328
1329 return 0;
1330 }
1331
1332 static int conflict_rename_rename_2to1(struct merge_options *o,
1333 struct rename_conflict_info *ci)
1334 {
1335 /* Two files, a & b, were renamed to the same thing, c. */
1336 struct diff_filespec *a = ci->pair1->one;
1337 struct diff_filespec *b = ci->pair2->one;
1338 struct diff_filespec *c1 = ci->pair1->two;
1339 struct diff_filespec *c2 = ci->pair2->two;
1340 char *path = c1->path; /* == c2->path */
1341 struct merge_file_info mfi_c1;
1342 struct merge_file_info mfi_c2;
1343 int ret;
1344
1345 output(o, 1, _("CONFLICT (rename/rename): "
1346 "Rename %s->%s in %s. "
1347 "Rename %s->%s in %s"),
1348 a->path, c1->path, ci->branch1,
1349 b->path, c2->path, ci->branch2);
1350
1351 remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path));
1352 remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path));
1353
1354 if (merge_file_special_markers(o, a, c1, &ci->ren1_other,
1355 o->branch1, c1->path,
1356 o->branch2, ci->ren1_other.path, &mfi_c1) ||
1357 merge_file_special_markers(o, b, &ci->ren2_other, c2,
1358 o->branch1, ci->ren2_other.path,
1359 o->branch2, c2->path, &mfi_c2))
1360 return -1;
1361
1362 if (o->call_depth) {
1363 /*
1364 * If mfi_c1.clean && mfi_c2.clean, then it might make
1365 * sense to do a two-way merge of those results. But, I
1366 * think in all cases, it makes sense to have the virtual
1367 * merge base just undo the renames; they can be detected
1368 * again later for the non-recursive merge.
1369 */
1370 remove_file(o, 0, path, 0);
1371 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path);
1372 if (!ret)
1373 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1374 b->path);
1375 } else {
1376 char *new_path1 = unique_path(o, path, ci->branch1);
1377 char *new_path2 = unique_path(o, path, ci->branch2);
1378 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1379 a->path, new_path1, b->path, new_path2);
1380 remove_file(o, 0, path, 0);
1381 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1);
1382 if (!ret)
1383 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1384 new_path2);
1385 free(new_path2);
1386 free(new_path1);
1387 }
1388
1389 return ret;
1390 }
1391
1392 static int process_renames(struct merge_options *o,
1393 struct string_list *a_renames,
1394 struct string_list *b_renames)
1395 {
1396 int clean_merge = 1, i, j;
1397 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
1398 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
1399 const struct rename *sre;
1400
1401 for (i = 0; i < a_renames->nr; i++) {
1402 sre = a_renames->items[i].util;
1403 string_list_insert(&a_by_dst, sre->pair->two->path)->util
1404 = (void *)sre;
1405 }
1406 for (i = 0; i < b_renames->nr; i++) {
1407 sre = b_renames->items[i].util;
1408 string_list_insert(&b_by_dst, sre->pair->two->path)->util
1409 = (void *)sre;
1410 }
1411
1412 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1413 struct string_list *renames1, *renames2Dst;
1414 struct rename *ren1 = NULL, *ren2 = NULL;
1415 const char *branch1, *branch2;
1416 const char *ren1_src, *ren1_dst;
1417 struct string_list_item *lookup;
1418
1419 if (i >= a_renames->nr) {
1420 ren2 = b_renames->items[j++].util;
1421 } else if (j >= b_renames->nr) {
1422 ren1 = a_renames->items[i++].util;
1423 } else {
1424 int compare = strcmp(a_renames->items[i].string,
1425 b_renames->items[j].string);
1426 if (compare <= 0)
1427 ren1 = a_renames->items[i++].util;
1428 if (compare >= 0)
1429 ren2 = b_renames->items[j++].util;
1430 }
1431
1432 /* TODO: refactor, so that 1/2 are not needed */
1433 if (ren1) {
1434 renames1 = a_renames;
1435 renames2Dst = &b_by_dst;
1436 branch1 = o->branch1;
1437 branch2 = o->branch2;
1438 } else {
1439 renames1 = b_renames;
1440 renames2Dst = &a_by_dst;
1441 branch1 = o->branch2;
1442 branch2 = o->branch1;
1443 SWAP(ren2, ren1);
1444 }
1445
1446 if (ren1->processed)
1447 continue;
1448 ren1->processed = 1;
1449 ren1->dst_entry->processed = 1;
1450 /* BUG: We should only mark src_entry as processed if we
1451 * are not dealing with a rename + add-source case.
1452 */
1453 ren1->src_entry->processed = 1;
1454
1455 ren1_src = ren1->pair->one->path;
1456 ren1_dst = ren1->pair->two->path;
1457
1458 if (ren2) {
1459 /* One file renamed on both sides */
1460 const char *ren2_src = ren2->pair->one->path;
1461 const char *ren2_dst = ren2->pair->two->path;
1462 enum rename_type rename_type;
1463 if (strcmp(ren1_src, ren2_src) != 0)
1464 die("BUG: ren1_src != ren2_src");
1465 ren2->dst_entry->processed = 1;
1466 ren2->processed = 1;
1467 if (strcmp(ren1_dst, ren2_dst) != 0) {
1468 rename_type = RENAME_ONE_FILE_TO_TWO;
1469 clean_merge = 0;
1470 } else {
1471 rename_type = RENAME_ONE_FILE_TO_ONE;
1472 /* BUG: We should only remove ren1_src in
1473 * the base stage (think of rename +
1474 * add-source cases).
1475 */
1476 remove_file(o, 1, ren1_src, 1);
1477 update_entry(ren1->dst_entry,
1478 ren1->pair->one,
1479 ren1->pair->two,
1480 ren2->pair->two);
1481 }
1482 setup_rename_conflict_info(rename_type,
1483 ren1->pair,
1484 ren2->pair,
1485 branch1,
1486 branch2,
1487 ren1->dst_entry,
1488 ren2->dst_entry,
1489 o,
1490 NULL,
1491 NULL);
1492 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
1493 /* Two different files renamed to the same thing */
1494 char *ren2_dst;
1495 ren2 = lookup->util;
1496 ren2_dst = ren2->pair->two->path;
1497 if (strcmp(ren1_dst, ren2_dst) != 0)
1498 die("BUG: ren1_dst != ren2_dst");
1499
1500 clean_merge = 0;
1501 ren2->processed = 1;
1502 /*
1503 * BUG: We should only mark src_entry as processed
1504 * if we are not dealing with a rename + add-source
1505 * case.
1506 */
1507 ren2->src_entry->processed = 1;
1508
1509 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
1510 ren1->pair,
1511 ren2->pair,
1512 branch1,
1513 branch2,
1514 ren1->dst_entry,
1515 ren2->dst_entry,
1516 o,
1517 ren1->src_entry,
1518 ren2->src_entry);
1519
1520 } else {
1521 /* Renamed in 1, maybe changed in 2 */
1522 /* we only use sha1 and mode of these */
1523 struct diff_filespec src_other, dst_other;
1524 int try_merge;
1525
1526 /*
1527 * unpack_trees loads entries from common-commit
1528 * into stage 1, from head-commit into stage 2, and
1529 * from merge-commit into stage 3. We keep track
1530 * of which side corresponds to the rename.
1531 */
1532 int renamed_stage = a_renames == renames1 ? 2 : 3;
1533 int other_stage = a_renames == renames1 ? 3 : 2;
1534
1535 /* BUG: We should only remove ren1_src in the base
1536 * stage and in other_stage (think of rename +
1537 * add-source case).
1538 */
1539 remove_file(o, 1, ren1_src,
1540 renamed_stage == 2 || !was_tracked(ren1_src));
1541
1542 oidcpy(&src_other.oid,
1543 &ren1->src_entry->stages[other_stage].oid);
1544 src_other.mode = ren1->src_entry->stages[other_stage].mode;
1545 oidcpy(&dst_other.oid,
1546 &ren1->dst_entry->stages[other_stage].oid);
1547 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1548 try_merge = 0;
1549
1550 if (oid_eq(&src_other.oid, &null_oid)) {
1551 setup_rename_conflict_info(RENAME_DELETE,
1552 ren1->pair,
1553 NULL,
1554 branch1,
1555 branch2,
1556 ren1->dst_entry,
1557 NULL,
1558 o,
1559 NULL,
1560 NULL);
1561 } else if ((dst_other.mode == ren1->pair->two->mode) &&
1562 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
1563 /*
1564 * Added file on the other side identical to
1565 * the file being renamed: clean merge.
1566 * Also, there is no need to overwrite the
1567 * file already in the working copy, so call
1568 * update_file_flags() instead of
1569 * update_file().
1570 */
1571 if (update_file_flags(o,
1572 &ren1->pair->two->oid,
1573 ren1->pair->two->mode,
1574 ren1_dst,
1575 1, /* update_cache */
1576 0 /* update_wd */))
1577 clean_merge = -1;
1578 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
1579 clean_merge = 0;
1580 try_merge = 1;
1581 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
1582 "%s added in %s"),
1583 ren1_src, ren1_dst, branch1,
1584 ren1_dst, branch2);
1585 if (o->call_depth) {
1586 struct merge_file_info mfi;
1587 if (merge_file_one(o, ren1_dst, &null_oid, 0,
1588 &ren1->pair->two->oid,
1589 ren1->pair->two->mode,
1590 &dst_other.oid,
1591 dst_other.mode,
1592 branch1, branch2, &mfi)) {
1593 clean_merge = -1;
1594 goto cleanup_and_return;
1595 }
1596 output(o, 1, _("Adding merged %s"), ren1_dst);
1597 if (update_file(o, 0, &mfi.oid,
1598 mfi.mode, ren1_dst))
1599 clean_merge = -1;
1600 try_merge = 0;
1601 } else {
1602 char *new_path = unique_path(o, ren1_dst, branch2);
1603 output(o, 1, _("Adding as %s instead"), new_path);
1604 if (update_file(o, 0, &dst_other.oid,
1605 dst_other.mode, new_path))
1606 clean_merge = -1;
1607 free(new_path);
1608 }
1609 } else
1610 try_merge = 1;
1611
1612 if (clean_merge < 0)
1613 goto cleanup_and_return;
1614 if (try_merge) {
1615 struct diff_filespec *one, *a, *b;
1616 src_other.path = (char *)ren1_src;
1617
1618 one = ren1->pair->one;
1619 if (a_renames == renames1) {
1620 a = ren1->pair->two;
1621 b = &src_other;
1622 } else {
1623 b = ren1->pair->two;
1624 a = &src_other;
1625 }
1626 update_entry(ren1->dst_entry, one, a, b);
1627 setup_rename_conflict_info(RENAME_NORMAL,
1628 ren1->pair,
1629 NULL,
1630 branch1,
1631 NULL,
1632 ren1->dst_entry,
1633 NULL,
1634 o,
1635 NULL,
1636 NULL);
1637 }
1638 }
1639 }
1640 cleanup_and_return:
1641 string_list_clear(&a_by_dst, 0);
1642 string_list_clear(&b_by_dst, 0);
1643
1644 return clean_merge;
1645 }
1646
1647 static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
1648 {
1649 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
1650 }
1651
1652 static int read_oid_strbuf(struct merge_options *o,
1653 const struct object_id *oid, struct strbuf *dst)
1654 {
1655 void *buf;
1656 enum object_type type;
1657 unsigned long size;
1658 buf = read_sha1_file(oid->hash, &type, &size);
1659 if (!buf)
1660 return err(o, _("cannot read object %s"), oid_to_hex(oid));
1661 if (type != OBJ_BLOB) {
1662 free(buf);
1663 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
1664 }
1665 strbuf_attach(dst, buf, size, size + 1);
1666 return 0;
1667 }
1668
1669 static int blob_unchanged(struct merge_options *opt,
1670 const struct object_id *o_oid,
1671 unsigned o_mode,
1672 const struct object_id *a_oid,
1673 unsigned a_mode,
1674 int renormalize, const char *path)
1675 {
1676 struct strbuf o = STRBUF_INIT;
1677 struct strbuf a = STRBUF_INIT;
1678 int ret = 0; /* assume changed for safety */
1679
1680 if (a_mode != o_mode)
1681 return 0;
1682 if (oid_eq(o_oid, a_oid))
1683 return 1;
1684 if (!renormalize)
1685 return 0;
1686
1687 assert(o_oid && a_oid);
1688 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
1689 goto error_return;
1690 /*
1691 * Note: binary | is used so that both renormalizations are
1692 * performed. Comparison can be skipped if both files are
1693 * unchanged since their sha1s have already been compared.
1694 */
1695 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
1696 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
1697 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1698
1699 error_return:
1700 strbuf_release(&o);
1701 strbuf_release(&a);
1702 return ret;
1703 }
1704
1705 static int handle_modify_delete(struct merge_options *o,
1706 const char *path,
1707 struct object_id *o_oid, int o_mode,
1708 struct object_id *a_oid, int a_mode,
1709 struct object_id *b_oid, int b_mode)
1710 {
1711 const char *modify_branch, *delete_branch;
1712 struct object_id *changed_oid;
1713 int changed_mode;
1714
1715 if (a_oid) {
1716 modify_branch = o->branch1;
1717 delete_branch = o->branch2;
1718 changed_oid = a_oid;
1719 changed_mode = a_mode;
1720 } else {
1721 modify_branch = o->branch2;
1722 delete_branch = o->branch1;
1723 changed_oid = b_oid;
1724 changed_mode = b_mode;
1725 }
1726
1727 return handle_change_delete(o,
1728 path, NULL,
1729 o_oid, o_mode,
1730 changed_oid, changed_mode,
1731 modify_branch, delete_branch,
1732 _("modify"), _("modified"));
1733 }
1734
1735 static int merge_content(struct merge_options *o,
1736 const char *path,
1737 struct object_id *o_oid, int o_mode,
1738 struct object_id *a_oid, int a_mode,
1739 struct object_id *b_oid, int b_mode,
1740 struct rename_conflict_info *rename_conflict_info)
1741 {
1742 const char *reason = _("content");
1743 const char *path1 = NULL, *path2 = NULL;
1744 struct merge_file_info mfi;
1745 struct diff_filespec one, a, b;
1746 unsigned df_conflict_remains = 0;
1747
1748 if (!o_oid) {
1749 reason = _("add/add");
1750 o_oid = (struct object_id *)&null_oid;
1751 }
1752 one.path = a.path = b.path = (char *)path;
1753 oidcpy(&one.oid, o_oid);
1754 one.mode = o_mode;
1755 oidcpy(&a.oid, a_oid);
1756 a.mode = a_mode;
1757 oidcpy(&b.oid, b_oid);
1758 b.mode = b_mode;
1759
1760 if (rename_conflict_info) {
1761 struct diff_filepair *pair1 = rename_conflict_info->pair1;
1762
1763 path1 = (o->branch1 == rename_conflict_info->branch1) ?
1764 pair1->two->path : pair1->one->path;
1765 /* If rename_conflict_info->pair2 != NULL, we are in
1766 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
1767 * normal rename.
1768 */
1769 path2 = (rename_conflict_info->pair2 ||
1770 o->branch2 == rename_conflict_info->branch1) ?
1771 pair1->two->path : pair1->one->path;
1772
1773 if (dir_in_way(path, !o->call_depth,
1774 S_ISGITLINK(pair1->two->mode)))
1775 df_conflict_remains = 1;
1776 }
1777 if (merge_file_special_markers(o, &one, &a, &b,
1778 o->branch1, path1,
1779 o->branch2, path2, &mfi))
1780 return -1;
1781
1782 if (mfi.clean && !df_conflict_remains &&
1783 oid_eq(&mfi.oid, a_oid) && mfi.mode == a_mode) {
1784 int path_renamed_outside_HEAD;
1785 output(o, 3, _("Skipped %s (merged same as existing)"), path);
1786 /*
1787 * The content merge resulted in the same file contents we
1788 * already had. We can return early if those file contents
1789 * are recorded at the correct path (which may not be true
1790 * if the merge involves a rename).
1791 */
1792 path_renamed_outside_HEAD = !path2 || !strcmp(path, path2);
1793 if (!path_renamed_outside_HEAD) {
1794 add_cacheinfo(o, mfi.mode, &mfi.oid, path,
1795 0, (!o->call_depth), 0);
1796 return mfi.clean;
1797 }
1798 } else
1799 output(o, 2, _("Auto-merging %s"), path);
1800
1801 if (!mfi.clean) {
1802 if (S_ISGITLINK(mfi.mode))
1803 reason = _("submodule");
1804 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
1805 reason, path);
1806 if (rename_conflict_info && !df_conflict_remains)
1807 if (update_stages(o, path, &one, &a, &b))
1808 return -1;
1809 }
1810
1811 if (df_conflict_remains) {
1812 char *new_path;
1813 if (o->call_depth) {
1814 remove_file_from_cache(path);
1815 } else {
1816 if (!mfi.clean) {
1817 if (update_stages(o, path, &one, &a, &b))
1818 return -1;
1819 } else {
1820 int file_from_stage2 = was_tracked(path);
1821 struct diff_filespec merged;
1822 oidcpy(&merged.oid, &mfi.oid);
1823 merged.mode = mfi.mode;
1824
1825 if (update_stages(o, path, NULL,
1826 file_from_stage2 ? &merged : NULL,
1827 file_from_stage2 ? NULL : &merged))
1828 return -1;
1829 }
1830
1831 }
1832 new_path = unique_path(o, path, rename_conflict_info->branch1);
1833 output(o, 1, _("Adding as %s instead"), new_path);
1834 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
1835 free(new_path);
1836 return -1;
1837 }
1838 free(new_path);
1839 mfi.clean = 0;
1840 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
1841 return -1;
1842 return mfi.clean;
1843 }
1844
1845 /* Per entry merge function */
1846 static int process_entry(struct merge_options *o,
1847 const char *path, struct stage_data *entry)
1848 {
1849 int clean_merge = 1;
1850 int normalize = o->renormalize;
1851 unsigned o_mode = entry->stages[1].mode;
1852 unsigned a_mode = entry->stages[2].mode;
1853 unsigned b_mode = entry->stages[3].mode;
1854 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
1855 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
1856 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
1857
1858 entry->processed = 1;
1859 if (entry->rename_conflict_info) {
1860 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
1861 switch (conflict_info->rename_type) {
1862 case RENAME_NORMAL:
1863 case RENAME_ONE_FILE_TO_ONE:
1864 clean_merge = merge_content(o, path,
1865 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
1866 conflict_info);
1867 break;
1868 case RENAME_DELETE:
1869 clean_merge = 0;
1870 if (conflict_rename_delete(o,
1871 conflict_info->pair1,
1872 conflict_info->branch1,
1873 conflict_info->branch2))
1874 clean_merge = -1;
1875 break;
1876 case RENAME_ONE_FILE_TO_TWO:
1877 clean_merge = 0;
1878 if (conflict_rename_rename_1to2(o, conflict_info))
1879 clean_merge = -1;
1880 break;
1881 case RENAME_TWO_FILES_TO_ONE:
1882 clean_merge = 0;
1883 if (conflict_rename_rename_2to1(o, conflict_info))
1884 clean_merge = -1;
1885 break;
1886 default:
1887 entry->processed = 0;
1888 break;
1889 }
1890 } else if (o_oid && (!a_oid || !b_oid)) {
1891 /* Case A: Deleted in one */
1892 if ((!a_oid && !b_oid) ||
1893 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
1894 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
1895 /* Deleted in both or deleted in one and
1896 * unchanged in the other */
1897 if (a_oid)
1898 output(o, 2, _("Removing %s"), path);
1899 /* do not touch working file if it did not exist */
1900 remove_file(o, 1, path, !a_oid);
1901 } else {
1902 /* Modify/delete; deleted side may have put a directory in the way */
1903 clean_merge = 0;
1904 if (handle_modify_delete(o, path, o_oid, o_mode,
1905 a_oid, a_mode, b_oid, b_mode))
1906 clean_merge = -1;
1907 }
1908 } else if ((!o_oid && a_oid && !b_oid) ||
1909 (!o_oid && !a_oid && b_oid)) {
1910 /* Case B: Added in one. */
1911 /* [nothing|directory] -> ([nothing|directory], file) */
1912
1913 const char *add_branch;
1914 const char *other_branch;
1915 unsigned mode;
1916 const struct object_id *oid;
1917 const char *conf;
1918
1919 if (a_oid) {
1920 add_branch = o->branch1;
1921 other_branch = o->branch2;
1922 mode = a_mode;
1923 oid = a_oid;
1924 conf = _("file/directory");
1925 } else {
1926 add_branch = o->branch2;
1927 other_branch = o->branch1;
1928 mode = b_mode;
1929 oid = b_oid;
1930 conf = _("directory/file");
1931 }
1932 if (dir_in_way(path,
1933 !o->call_depth && !S_ISGITLINK(a_mode),
1934 0)) {
1935 char *new_path = unique_path(o, path, add_branch);
1936 clean_merge = 0;
1937 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
1938 "Adding %s as %s"),
1939 conf, path, other_branch, path, new_path);
1940 if (update_file(o, 0, oid, mode, new_path))
1941 clean_merge = -1;
1942 else if (o->call_depth)
1943 remove_file_from_cache(path);
1944 free(new_path);
1945 } else {
1946 output(o, 2, _("Adding %s"), path);
1947 /* do not overwrite file if already present */
1948 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
1949 clean_merge = -1;
1950 }
1951 } else if (a_oid && b_oid) {
1952 /* Case C: Added in both (check for same permissions) and */
1953 /* case D: Modified in both, but differently. */
1954 clean_merge = merge_content(o, path,
1955 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
1956 NULL);
1957 } else if (!o_oid && !a_oid && !b_oid) {
1958 /*
1959 * this entry was deleted altogether. a_mode == 0 means
1960 * we had that path and want to actively remove it.
1961 */
1962 remove_file(o, 1, path, !a_mode);
1963 } else
1964 die("BUG: fatal merge failure, shouldn't happen.");
1965
1966 return clean_merge;
1967 }
1968
1969 int merge_trees(struct merge_options *o,
1970 struct tree *head,
1971 struct tree *merge,
1972 struct tree *common,
1973 struct tree **result)
1974 {
1975 int code, clean;
1976
1977 if (o->subtree_shift) {
1978 merge = shift_tree_object(head, merge, o->subtree_shift);
1979 common = shift_tree_object(head, common, o->subtree_shift);
1980 }
1981
1982 if (oid_eq(&common->object.oid, &merge->object.oid)) {
1983 struct strbuf sb = STRBUF_INIT;
1984
1985 if (!o->call_depth && index_has_changes(&sb)) {
1986 err(o, _("Dirty index: cannot merge (dirty: %s)"),
1987 sb.buf);
1988 return 0;
1989 }
1990 output(o, 0, _("Already up to date!"));
1991 *result = head;
1992 return 1;
1993 }
1994
1995 code = git_merge_trees(o->call_depth, common, head, merge);
1996
1997 if (code != 0) {
1998 if (show(o, 4) || o->call_depth)
1999 err(o, _("merging of trees %s and %s failed"),
2000 oid_to_hex(&head->object.oid),
2001 oid_to_hex(&merge->object.oid));
2002 return -1;
2003 }
2004
2005 if (unmerged_cache()) {
2006 struct string_list *entries, *re_head, *re_merge;
2007 int i;
2008 /*
2009 * Only need the hashmap while processing entries, so
2010 * initialize it here and free it when we are done running
2011 * through the entries. Keeping it in the merge_options as
2012 * opposed to decaring a local hashmap is for convenience
2013 * so that we don't have to pass it to around.
2014 */
2015 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
2016 get_files_dirs(o, head);
2017 get_files_dirs(o, merge);
2018
2019 entries = get_unmerged();
2020 re_head = get_renames(o, head, common, head, merge, entries);
2021 re_merge = get_renames(o, merge, common, head, merge, entries);
2022 clean = process_renames(o, re_head, re_merge);
2023 record_df_conflict_files(o, entries);
2024 if (clean < 0)
2025 goto cleanup;
2026 for (i = entries->nr-1; 0 <= i; i--) {
2027 const char *path = entries->items[i].string;
2028 struct stage_data *e = entries->items[i].util;
2029 if (!e->processed) {
2030 int ret = process_entry(o, path, e);
2031 if (!ret)
2032 clean = 0;
2033 else if (ret < 0) {
2034 clean = ret;
2035 goto cleanup;
2036 }
2037 }
2038 }
2039 for (i = 0; i < entries->nr; i++) {
2040 struct stage_data *e = entries->items[i].util;
2041 if (!e->processed)
2042 die("BUG: unprocessed path??? %s",
2043 entries->items[i].string);
2044 }
2045
2046 cleanup:
2047 string_list_clear(re_merge, 0);
2048 string_list_clear(re_head, 0);
2049 string_list_clear(entries, 1);
2050
2051 hashmap_free(&o->current_file_dir_set, 1);
2052
2053 free(re_merge);
2054 free(re_head);
2055 free(entries);
2056
2057 if (clean < 0)
2058 return clean;
2059 }
2060 else
2061 clean = 1;
2062
2063 if (o->call_depth && !(*result = write_tree_from_memory(o)))
2064 return -1;
2065
2066 return clean;
2067 }
2068
2069 static struct commit_list *reverse_commit_list(struct commit_list *list)
2070 {
2071 struct commit_list *next = NULL, *current, *backup;
2072 for (current = list; current; current = backup) {
2073 backup = current->next;
2074 current->next = next;
2075 next = current;
2076 }
2077 return next;
2078 }
2079
2080 /*
2081 * Merge the commits h1 and h2, return the resulting virtual
2082 * commit object and a flag indicating the cleanness of the merge.
2083 */
2084 int merge_recursive(struct merge_options *o,
2085 struct commit *h1,
2086 struct commit *h2,
2087 struct commit_list *ca,
2088 struct commit **result)
2089 {
2090 struct commit_list *iter;
2091 struct commit *merged_common_ancestors;
2092 struct tree *mrtree = mrtree;
2093 int clean;
2094
2095 if (show(o, 4)) {
2096 output(o, 4, _("Merging:"));
2097 output_commit_title(o, h1);
2098 output_commit_title(o, h2);
2099 }
2100
2101 if (!ca) {
2102 ca = get_merge_bases(h1, h2);
2103 ca = reverse_commit_list(ca);
2104 }
2105
2106 if (show(o, 5)) {
2107 unsigned cnt = commit_list_count(ca);
2108
2109 output(o, 5, Q_("found %u common ancestor:",
2110 "found %u common ancestors:", cnt), cnt);
2111 for (iter = ca; iter; iter = iter->next)
2112 output_commit_title(o, iter->item);
2113 }
2114
2115 merged_common_ancestors = pop_commit(&ca);
2116 if (merged_common_ancestors == NULL) {
2117 /* if there is no common ancestor, use an empty tree */
2118 struct tree *tree;
2119
2120 tree = lookup_tree(the_hash_algo->empty_tree);
2121 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
2122 }
2123
2124 for (iter = ca; iter; iter = iter->next) {
2125 const char *saved_b1, *saved_b2;
2126 o->call_depth++;
2127 /*
2128 * When the merge fails, the result contains files
2129 * with conflict markers. The cleanness flag is
2130 * ignored (unless indicating an error), it was never
2131 * actually used, as result of merge_trees has always
2132 * overwritten it: the committed "conflicts" were
2133 * already resolved.
2134 */
2135 discard_cache();
2136 saved_b1 = o->branch1;
2137 saved_b2 = o->branch2;
2138 o->branch1 = "Temporary merge branch 1";
2139 o->branch2 = "Temporary merge branch 2";
2140 if (merge_recursive(o, merged_common_ancestors, iter->item,
2141 NULL, &merged_common_ancestors) < 0)
2142 return -1;
2143 o->branch1 = saved_b1;
2144 o->branch2 = saved_b2;
2145 o->call_depth--;
2146
2147 if (!merged_common_ancestors)
2148 return err(o, _("merge returned no commit"));
2149 }
2150
2151 discard_cache();
2152 if (!o->call_depth)
2153 read_cache();
2154
2155 o->ancestor = "merged common ancestors";
2156 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
2157 &mrtree);
2158 if (clean < 0) {
2159 flush_output(o);
2160 return clean;
2161 }
2162
2163 if (o->call_depth) {
2164 *result = make_virtual_commit(mrtree, "merged tree");
2165 commit_list_insert(h1, &(*result)->parents);
2166 commit_list_insert(h2, &(*result)->parents->next);
2167 }
2168 flush_output(o);
2169 if (!o->call_depth && o->buffer_output < 2)
2170 strbuf_release(&o->obuf);
2171 if (show(o, 2))
2172 diff_warn_rename_limit("merge.renamelimit",
2173 o->needed_rename_limit, 0);
2174 return clean;
2175 }
2176
2177 static struct commit *get_ref(const struct object_id *oid, const char *name)
2178 {
2179 struct object *object;
2180
2181 object = deref_tag(parse_object(oid), name, strlen(name));
2182 if (!object)
2183 return NULL;
2184 if (object->type == OBJ_TREE)
2185 return make_virtual_commit((struct tree*)object, name);
2186 if (object->type != OBJ_COMMIT)
2187 return NULL;
2188 if (parse_commit((struct commit *)object))
2189 return NULL;
2190 return (struct commit *)object;
2191 }
2192
2193 int merge_recursive_generic(struct merge_options *o,
2194 const struct object_id *head,
2195 const struct object_id *merge,
2196 int num_base_list,
2197 const struct object_id **base_list,
2198 struct commit **result)
2199 {
2200 int clean;
2201 struct lock_file lock = LOCK_INIT;
2202 struct commit *head_commit = get_ref(head, o->branch1);
2203 struct commit *next_commit = get_ref(merge, o->branch2);
2204 struct commit_list *ca = NULL;
2205
2206 if (base_list) {
2207 int i;
2208 for (i = 0; i < num_base_list; ++i) {
2209 struct commit *base;
2210 if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i]))))
2211 return err(o, _("Could not parse object '%s'"),
2212 oid_to_hex(base_list[i]));
2213 commit_list_insert(base, &ca);
2214 }
2215 }
2216
2217 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
2218 clean = merge_recursive(o, head_commit, next_commit, ca,
2219 result);
2220 if (clean < 0)
2221 return clean;
2222
2223 if (active_cache_changed &&
2224 write_locked_index(&the_index, &lock, COMMIT_LOCK))
2225 return err(o, _("Unable to write index."));
2226
2227 return clean ? 0 : 1;
2228 }
2229
2230 static void merge_recursive_config(struct merge_options *o)
2231 {
2232 git_config_get_int("merge.verbosity", &o->verbosity);
2233 git_config_get_int("diff.renamelimit", &o->diff_rename_limit);
2234 git_config_get_int("merge.renamelimit", &o->merge_rename_limit);
2235 git_config(git_xmerge_config, NULL);
2236 }
2237
2238 void init_merge_options(struct merge_options *o)
2239 {
2240 const char *merge_verbosity;
2241 memset(o, 0, sizeof(struct merge_options));
2242 o->verbosity = 2;
2243 o->buffer_output = 1;
2244 o->diff_rename_limit = -1;
2245 o->merge_rename_limit = -1;
2246 o->renormalize = 0;
2247 o->detect_rename = 1;
2248 merge_recursive_config(o);
2249 merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
2250 if (merge_verbosity)
2251 o->verbosity = strtol(merge_verbosity, NULL, 10);
2252 if (o->verbosity >= 5)
2253 o->buffer_output = 0;
2254 strbuf_init(&o->obuf, 0);
2255 string_list_init(&o->df_conflict_file_set, 1);
2256 }
2257
2258 int parse_merge_opt(struct merge_options *o, const char *s)
2259 {
2260 const char *arg;
2261
2262 if (!s || !*s)
2263 return -1;
2264 if (!strcmp(s, "ours"))
2265 o->recursive_variant = MERGE_RECURSIVE_OURS;
2266 else if (!strcmp(s, "theirs"))
2267 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
2268 else if (!strcmp(s, "subtree"))
2269 o->subtree_shift = "";
2270 else if (skip_prefix(s, "subtree=", &arg))
2271 o->subtree_shift = arg;
2272 else if (!strcmp(s, "patience"))
2273 o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF);
2274 else if (!strcmp(s, "histogram"))
2275 o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF);
2276 else if (skip_prefix(s, "diff-algorithm=", &arg)) {
2277 long value = parse_algorithm_value(arg);
2278 if (value < 0)
2279 return -1;
2280 /* clear out previous settings */
2281 DIFF_XDL_CLR(o, NEED_MINIMAL);
2282 o->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
2283 o->xdl_opts |= value;
2284 }
2285 else if (!strcmp(s, "ignore-space-change"))
2286 DIFF_XDL_SET(o, IGNORE_WHITESPACE_CHANGE);
2287 else if (!strcmp(s, "ignore-all-space"))
2288 DIFF_XDL_SET(o, IGNORE_WHITESPACE);
2289 else if (!strcmp(s, "ignore-space-at-eol"))
2290 DIFF_XDL_SET(o, IGNORE_WHITESPACE_AT_EOL);
2291 else if (!strcmp(s, "ignore-cr-at-eol"))
2292 DIFF_XDL_SET(o, IGNORE_CR_AT_EOL);
2293 else if (!strcmp(s, "renormalize"))
2294 o->renormalize = 1;
2295 else if (!strcmp(s, "no-renormalize"))
2296 o->renormalize = 0;
2297 else if (!strcmp(s, "no-renames"))
2298 o->detect_rename = 0;
2299 else if (!strcmp(s, "find-renames")) {
2300 o->detect_rename = 1;
2301 o->rename_score = 0;
2302 }
2303 else if (skip_prefix(s, "find-renames=", &arg) ||
2304 skip_prefix(s, "rename-threshold=", &arg)) {
2305 if ((o->rename_score = parse_rename_score(&arg)) == -1 || *arg != 0)
2306 return -1;
2307 o->detect_rename = 1;
2308 }
2309 else
2310 return -1;
2311 return 0;
2312 }