8020d4b5139fbb7c2661e4e032845c703542605e
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 "advice.h"
7 #include "cache.h"
8 #include "cache-tree.h"
9 #include "commit.h"
10 #include "blob.h"
11 #include "builtin.h"
12 #include "tree-walk.h"
13 #include "diff.h"
14 #include "diffcore.h"
15 #include "tag.h"
16 #include "unpack-trees.h"
17 #include "string-list.h"
18 #include "xdiff-interface.h"
19 #include "ll-merge.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
22 #include "dir.h"
23 #include "submodule.h"
25 static struct tree *shift_tree_object(struct tree *one, struct tree *two,
26 const char *subtree_shift)
27 {
28 unsigned char shifted[20];
30 if (!*subtree_shift) {
31 shift_tree(one->object.sha1, two->object.sha1, shifted, 0);
32 } else {
33 shift_tree_by(one->object.sha1, two->object.sha1, shifted,
34 subtree_shift);
35 }
36 if (!hashcmp(two->object.sha1, shifted))
37 return two;
38 return lookup_tree(shifted);
39 }
41 /*
42 * A virtual commit has (const char *)commit->util set to the name.
43 */
45 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
46 {
47 struct commit *commit = xcalloc(1, sizeof(struct commit));
48 commit->tree = tree;
49 commit->util = (void*)comment;
50 /* avoid warnings */
51 commit->object.parsed = 1;
52 return commit;
53 }
55 /*
56 * Since we use get_tree_entry(), which does not put the read object into
57 * the object pool, we cannot rely on a == b.
58 */
59 static int sha_eq(const unsigned char *a, const unsigned char *b)
60 {
61 if (!a && !b)
62 return 2;
63 return a && b && hashcmp(a, b) == 0;
64 }
66 enum rename_type {
67 RENAME_NORMAL = 0,
68 RENAME_DELETE,
69 RENAME_ONE_FILE_TO_ONE,
70 RENAME_ONE_FILE_TO_TWO
71 };
73 struct rename_conflict_info {
74 enum rename_type rename_type;
75 struct diff_filepair *pair1;
76 struct diff_filepair *pair2;
77 const char *branch1;
78 const char *branch2;
79 struct stage_data *dst_entry1;
80 struct stage_data *dst_entry2;
81 };
83 /*
84 * Since we want to write the index eventually, we cannot reuse the index
85 * for these (temporary) data.
86 */
87 struct stage_data {
88 struct {
89 unsigned mode;
90 unsigned char sha[20];
91 } stages[4];
92 struct rename_conflict_info *rename_conflict_info;
93 unsigned processed:1;
94 };
96 static inline void setup_rename_conflict_info(enum rename_type rename_type,
97 struct diff_filepair *pair1,
98 struct diff_filepair *pair2,
99 const char *branch1,
100 const char *branch2,
101 struct stage_data *dst_entry1,
102 struct stage_data *dst_entry2)
103 {
104 struct rename_conflict_info *ci = xcalloc(1, sizeof(struct rename_conflict_info));
105 ci->rename_type = rename_type;
106 ci->pair1 = pair1;
107 ci->branch1 = branch1;
108 ci->branch2 = branch2;
110 ci->dst_entry1 = dst_entry1;
111 dst_entry1->rename_conflict_info = ci;
112 dst_entry1->processed = 0;
114 assert(!pair2 == !dst_entry2);
115 if (dst_entry2) {
116 ci->dst_entry2 = dst_entry2;
117 ci->pair2 = pair2;
118 dst_entry2->rename_conflict_info = ci;
119 }
120 }
122 static int show(struct merge_options *o, int v)
123 {
124 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
125 }
127 static void flush_output(struct merge_options *o)
128 {
129 if (o->obuf.len) {
130 fputs(o->obuf.buf, stdout);
131 strbuf_reset(&o->obuf);
132 }
133 }
135 __attribute__((format (printf, 3, 4)))
136 static void output(struct merge_options *o, int v, const char *fmt, ...)
137 {
138 va_list ap;
140 if (!show(o, v))
141 return;
143 strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
144 memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
145 strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
147 va_start(ap, fmt);
148 strbuf_vaddf(&o->obuf, fmt, ap);
149 va_end(ap);
151 strbuf_add(&o->obuf, "\n", 1);
152 if (!o->buffer_output)
153 flush_output(o);
154 }
156 static void output_commit_title(struct merge_options *o, struct commit *commit)
157 {
158 int i;
159 flush_output(o);
160 for (i = o->call_depth; i--;)
161 fputs(" ", stdout);
162 if (commit->util)
163 printf("virtual %s\n", (char *)commit->util);
164 else {
165 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
166 if (parse_commit(commit) != 0)
167 printf("(bad commit)\n");
168 else {
169 const char *title;
170 int len = find_commit_subject(commit->buffer, &title);
171 if (len)
172 printf("%.*s\n", len, title);
173 }
174 }
175 }
177 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
178 const char *path, int stage, int refresh, int options)
179 {
180 struct cache_entry *ce;
181 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
182 if (!ce)
183 return error("addinfo_cache failed for path '%s'", path);
184 return add_cache_entry(ce, options);
185 }
187 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
188 {
189 parse_tree(tree);
190 init_tree_desc(desc, tree->buffer, tree->size);
191 }
193 static int git_merge_trees(int index_only,
194 struct tree *common,
195 struct tree *head,
196 struct tree *merge)
197 {
198 int rc;
199 struct tree_desc t[3];
200 struct unpack_trees_options opts;
202 memset(&opts, 0, sizeof(opts));
203 if (index_only)
204 opts.index_only = 1;
205 else
206 opts.update = 1;
207 opts.merge = 1;
208 opts.head_idx = 2;
209 opts.fn = threeway_merge;
210 opts.src_index = &the_index;
211 opts.dst_index = &the_index;
212 setup_unpack_trees_porcelain(&opts, "merge");
214 init_tree_desc_from_tree(t+0, common);
215 init_tree_desc_from_tree(t+1, head);
216 init_tree_desc_from_tree(t+2, merge);
218 rc = unpack_trees(3, t, &opts);
219 cache_tree_free(&active_cache_tree);
220 return rc;
221 }
223 struct tree *write_tree_from_memory(struct merge_options *o)
224 {
225 struct tree *result = NULL;
227 if (unmerged_cache()) {
228 int i;
229 fprintf(stderr, "BUG: There are unmerged index entries:\n");
230 for (i = 0; i < active_nr; i++) {
231 struct cache_entry *ce = active_cache[i];
232 if (ce_stage(ce))
233 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
234 (int)ce_namelen(ce), ce->name);
235 }
236 die("Bug in merge-recursive.c");
237 }
239 if (!active_cache_tree)
240 active_cache_tree = cache_tree();
242 if (!cache_tree_fully_valid(active_cache_tree) &&
243 cache_tree_update(active_cache_tree,
244 active_cache, active_nr, 0, 0) < 0)
245 die("error building trees");
247 result = lookup_tree(active_cache_tree->sha1);
249 return result;
250 }
252 static int save_files_dirs(const unsigned char *sha1,
253 const char *base, int baselen, const char *path,
254 unsigned int mode, int stage, void *context)
255 {
256 int len = strlen(path);
257 char *newpath = xmalloc(baselen + len + 1);
258 struct merge_options *o = context;
260 memcpy(newpath, base, baselen);
261 memcpy(newpath + baselen, path, len);
262 newpath[baselen + len] = '\0';
264 if (S_ISDIR(mode))
265 string_list_insert(&o->current_directory_set, newpath);
266 else
267 string_list_insert(&o->current_file_set, newpath);
268 free(newpath);
270 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
271 }
273 static int get_files_dirs(struct merge_options *o, struct tree *tree)
274 {
275 int n;
276 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
277 return 0;
278 n = o->current_file_set.nr + o->current_directory_set.nr;
279 return n;
280 }
282 /*
283 * Returns an index_entry instance which doesn't have to correspond to
284 * a real cache entry in Git's index.
285 */
286 static struct stage_data *insert_stage_data(const char *path,
287 struct tree *o, struct tree *a, struct tree *b,
288 struct string_list *entries)
289 {
290 struct string_list_item *item;
291 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
292 get_tree_entry(o->object.sha1, path,
293 e->stages[1].sha, &e->stages[1].mode);
294 get_tree_entry(a->object.sha1, path,
295 e->stages[2].sha, &e->stages[2].mode);
296 get_tree_entry(b->object.sha1, path,
297 e->stages[3].sha, &e->stages[3].mode);
298 item = string_list_insert(entries, path);
299 item->util = e;
300 return e;
301 }
303 /*
304 * Create a dictionary mapping file names to stage_data objects. The
305 * dictionary contains one entry for every path with a non-zero stage entry.
306 */
307 static struct string_list *get_unmerged(void)
308 {
309 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
310 int i;
312 unmerged->strdup_strings = 1;
314 for (i = 0; i < active_nr; i++) {
315 struct string_list_item *item;
316 struct stage_data *e;
317 struct cache_entry *ce = active_cache[i];
318 if (!ce_stage(ce))
319 continue;
321 item = string_list_lookup(unmerged, ce->name);
322 if (!item) {
323 item = string_list_insert(unmerged, ce->name);
324 item->util = xcalloc(1, sizeof(struct stage_data));
325 }
326 e = item->util;
327 e->stages[ce_stage(ce)].mode = ce->ce_mode;
328 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
329 }
331 return unmerged;
332 }
334 static int string_list_df_name_compare(const void *a, const void *b)
335 {
336 const struct string_list_item *one = a;
337 const struct string_list_item *two = b;
338 int onelen = strlen(one->string);
339 int twolen = strlen(two->string);
340 /*
341 * Here we only care that entries for D/F conflicts are
342 * adjacent, in particular with the file of the D/F conflict
343 * appearing before files below the corresponding directory.
344 * The order of the rest of the list is irrelevant for us.
345 *
346 * To achieve this, we sort with df_name_compare and provide
347 * the mode S_IFDIR so that D/F conflicts will sort correctly.
348 * We use the mode S_IFDIR for everything else for simplicity,
349 * since in other cases any changes in their order due to
350 * sorting cause no problems for us.
351 */
352 int cmp = df_name_compare(one->string, onelen, S_IFDIR,
353 two->string, twolen, S_IFDIR);
354 /*
355 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
356 * that 'foo' comes before 'foo/bar'.
357 */
358 if (cmp)
359 return cmp;
360 return onelen - twolen;
361 }
363 static void record_df_conflict_files(struct merge_options *o,
364 struct string_list *entries)
365 {
366 /* If there is a D/F conflict and the file for such a conflict
367 * currently exist in the working copy, we want to allow it to be
368 * removed to make room for the corresponding directory if needed.
369 * The files underneath the directories of such D/F conflicts will
370 * be processed before the corresponding file involved in the D/F
371 * conflict. If the D/F directory ends up being removed by the
372 * merge, then we won't have to touch the D/F file. If the D/F
373 * directory needs to be written to the working copy, then the D/F
374 * file will simply be removed (in make_room_for_path()) to make
375 * room for the necessary paths. Note that if both the directory
376 * and the file need to be present, then the D/F file will be
377 * reinstated with a new unique name at the time it is processed.
378 */
379 const char *last_file = NULL;
380 int last_len = 0;
381 int i;
383 /*
384 * If we're merging merge-bases, we don't want to bother with
385 * any working directory changes.
386 */
387 if (o->call_depth)
388 return;
390 /* Ensure D/F conflicts are adjacent in the entries list. */
391 qsort(entries->items, entries->nr, sizeof(*entries->items),
392 string_list_df_name_compare);
394 string_list_clear(&o->df_conflict_file_set, 1);
395 for (i = 0; i < entries->nr; i++) {
396 const char *path = entries->items[i].string;
397 int len = strlen(path);
398 struct stage_data *e = entries->items[i].util;
400 /*
401 * Check if last_file & path correspond to a D/F conflict;
402 * i.e. whether path is last_file+'/'+<something>.
403 * If so, record that it's okay to remove last_file to make
404 * room for path and friends if needed.
405 */
406 if (last_file &&
407 len > last_len &&
408 memcmp(path, last_file, last_len) == 0 &&
409 path[last_len] == '/') {
410 string_list_insert(&o->df_conflict_file_set, last_file);
411 }
413 /*
414 * Determine whether path could exist as a file in the
415 * working directory as a possible D/F conflict. This
416 * will only occur when it exists in stage 2 as a
417 * file.
418 */
419 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
420 last_file = path;
421 last_len = len;
422 } else {
423 last_file = NULL;
424 }
425 }
426 }
428 struct rename {
429 struct diff_filepair *pair;
430 struct stage_data *src_entry;
431 struct stage_data *dst_entry;
432 unsigned processed:1;
433 };
435 /*
436 * Get information of all renames which occurred between 'o_tree' and
437 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
438 * 'b_tree') to be able to associate the correct cache entries with
439 * the rename information. 'tree' is always equal to either a_tree or b_tree.
440 */
441 static struct string_list *get_renames(struct merge_options *o,
442 struct tree *tree,
443 struct tree *o_tree,
444 struct tree *a_tree,
445 struct tree *b_tree,
446 struct string_list *entries)
447 {
448 int i;
449 struct string_list *renames;
450 struct diff_options opts;
452 renames = xcalloc(1, sizeof(struct string_list));
453 diff_setup(&opts);
454 DIFF_OPT_SET(&opts, RECURSIVE);
455 opts.detect_rename = DIFF_DETECT_RENAME;
456 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
457 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
458 1000;
459 opts.rename_score = o->rename_score;
460 opts.show_rename_progress = o->show_rename_progress;
461 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
462 if (diff_setup_done(&opts) < 0)
463 die("diff setup failed");
464 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
465 diffcore_std(&opts);
466 if (opts.needed_rename_limit > o->needed_rename_limit)
467 o->needed_rename_limit = opts.needed_rename_limit;
468 for (i = 0; i < diff_queued_diff.nr; ++i) {
469 struct string_list_item *item;
470 struct rename *re;
471 struct diff_filepair *pair = diff_queued_diff.queue[i];
472 if (pair->status != 'R') {
473 diff_free_filepair(pair);
474 continue;
475 }
476 re = xmalloc(sizeof(*re));
477 re->processed = 0;
478 re->pair = pair;
479 item = string_list_lookup(entries, re->pair->one->path);
480 if (!item)
481 re->src_entry = insert_stage_data(re->pair->one->path,
482 o_tree, a_tree, b_tree, entries);
483 else
484 re->src_entry = item->util;
486 item = string_list_lookup(entries, re->pair->two->path);
487 if (!item)
488 re->dst_entry = insert_stage_data(re->pair->two->path,
489 o_tree, a_tree, b_tree, entries);
490 else
491 re->dst_entry = item->util;
492 item = string_list_insert(renames, pair->one->path);
493 item->util = re;
494 }
495 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
496 diff_queued_diff.nr = 0;
497 diff_flush(&opts);
498 return renames;
499 }
501 static int update_stages(const char *path, const struct diff_filespec *o,
502 const struct diff_filespec *a,
503 const struct diff_filespec *b)
504 {
505 int clear = 1;
506 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
507 if (clear)
508 if (remove_file_from_cache(path))
509 return -1;
510 if (o)
511 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
512 return -1;
513 if (a)
514 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
515 return -1;
516 if (b)
517 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
518 return -1;
519 return 0;
520 }
522 static void update_entry(struct stage_data *entry,
523 struct diff_filespec *o,
524 struct diff_filespec *a,
525 struct diff_filespec *b)
526 {
527 entry->processed = 0;
528 entry->stages[1].mode = o->mode;
529 entry->stages[2].mode = a->mode;
530 entry->stages[3].mode = b->mode;
531 hashcpy(entry->stages[1].sha, o->sha1);
532 hashcpy(entry->stages[2].sha, a->sha1);
533 hashcpy(entry->stages[3].sha, b->sha1);
534 }
536 static int remove_file(struct merge_options *o, int clean,
537 const char *path, int no_wd)
538 {
539 int update_cache = o->call_depth || clean;
540 int update_working_directory = !o->call_depth && !no_wd;
542 if (update_cache) {
543 if (remove_file_from_cache(path))
544 return -1;
545 }
546 if (update_working_directory) {
547 if (remove_path(path))
548 return -1;
549 }
550 return 0;
551 }
553 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
554 {
555 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
556 int suffix = 0;
557 struct stat st;
558 char *p = newpath + strlen(path);
559 strcpy(newpath, path);
560 *(p++) = '~';
561 strcpy(p, branch);
562 for (; *p; ++p)
563 if ('/' == *p)
564 *p = '_';
565 while (string_list_has_string(&o->current_file_set, newpath) ||
566 string_list_has_string(&o->current_directory_set, newpath) ||
567 lstat(newpath, &st) == 0)
568 sprintf(p, "_%d", suffix++);
570 string_list_insert(&o->current_file_set, newpath);
571 return newpath;
572 }
574 static void flush_buffer(int fd, const char *buf, unsigned long size)
575 {
576 while (size > 0) {
577 long ret = write_in_full(fd, buf, size);
578 if (ret < 0) {
579 /* Ignore epipe */
580 if (errno == EPIPE)
581 break;
582 die_errno("merge-recursive");
583 } else if (!ret) {
584 die("merge-recursive: disk full?");
585 }
586 size -= ret;
587 buf += ret;
588 }
589 }
591 static int dir_in_way(const char *path, int check_working_copy)
592 {
593 int pos, pathlen = strlen(path);
594 char *dirpath = xmalloc(pathlen + 2);
595 struct stat st;
597 strcpy(dirpath, path);
598 dirpath[pathlen] = '/';
599 dirpath[pathlen+1] = '\0';
601 pos = cache_name_pos(dirpath, pathlen+1);
603 if (pos < 0)
604 pos = -1 - pos;
605 if (pos < active_nr &&
606 !strncmp(dirpath, active_cache[pos]->name, pathlen+1)) {
607 free(dirpath);
608 return 1;
609 }
611 free(dirpath);
612 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode);
613 }
615 static int was_tracked(const char *path)
616 {
617 int pos = cache_name_pos(path, strlen(path));
619 if (pos < 0)
620 pos = -1 - pos;
621 while (pos < active_nr &&
622 !strcmp(path, active_cache[pos]->name)) {
623 /*
624 * If stage #0, it is definitely tracked.
625 * If it has stage #2 then it was tracked
626 * before this merge started. All other
627 * cases the path was not tracked.
628 */
629 switch (ce_stage(active_cache[pos])) {
630 case 0:
631 case 2:
632 return 1;
633 }
634 pos++;
635 }
636 return 0;
637 }
639 static int would_lose_untracked(const char *path)
640 {
641 return !was_tracked(path) && file_exists(path);
642 }
644 static int make_room_for_path(struct merge_options *o, const char *path)
645 {
646 int status, i;
647 const char *msg = "failed to create path '%s'%s";
649 /* Unlink any D/F conflict files that are in the way */
650 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
651 const char *df_path = o->df_conflict_file_set.items[i].string;
652 size_t pathlen = strlen(path);
653 size_t df_pathlen = strlen(df_path);
654 if (df_pathlen < pathlen &&
655 path[df_pathlen] == '/' &&
656 strncmp(path, df_path, df_pathlen) == 0) {
657 output(o, 3,
658 "Removing %s to make room for subdirectory\n",
659 df_path);
660 unlink(df_path);
661 unsorted_string_list_delete_item(&o->df_conflict_file_set,
662 i, 0);
663 break;
664 }
665 }
667 /* Make sure leading directories are created */
668 status = safe_create_leading_directories_const(path);
669 if (status) {
670 if (status == -3) {
671 /* something else exists */
672 error(msg, path, ": perhaps a D/F conflict?");
673 return -1;
674 }
675 die(msg, path, "");
676 }
678 /*
679 * Do not unlink a file in the work tree if we are not
680 * tracking it.
681 */
682 if (would_lose_untracked(path))
683 return error("refusing to lose untracked file at '%s'",
684 path);
686 /* Successful unlink is good.. */
687 if (!unlink(path))
688 return 0;
689 /* .. and so is no existing file */
690 if (errno == ENOENT)
691 return 0;
692 /* .. but not some other error (who really cares what?) */
693 return error(msg, path, ": perhaps a D/F conflict?");
694 }
696 static void update_file_flags(struct merge_options *o,
697 const unsigned char *sha,
698 unsigned mode,
699 const char *path,
700 int update_cache,
701 int update_wd)
702 {
703 if (o->call_depth)
704 update_wd = 0;
706 if (update_wd) {
707 enum object_type type;
708 void *buf;
709 unsigned long size;
711 if (S_ISGITLINK(mode)) {
712 /*
713 * We may later decide to recursively descend into
714 * the submodule directory and update its index
715 * and/or work tree, but we do not do that now.
716 */
717 update_wd = 0;
718 goto update_index;
719 }
721 buf = read_sha1_file(sha, &type, &size);
722 if (!buf)
723 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
724 if (type != OBJ_BLOB)
725 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
726 if (S_ISREG(mode)) {
727 struct strbuf strbuf = STRBUF_INIT;
728 if (convert_to_working_tree(path, buf, size, &strbuf)) {
729 free(buf);
730 size = strbuf.len;
731 buf = strbuf_detach(&strbuf, NULL);
732 }
733 }
735 if (make_room_for_path(o, path) < 0) {
736 update_wd = 0;
737 free(buf);
738 goto update_index;
739 }
740 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
741 int fd;
742 if (mode & 0100)
743 mode = 0777;
744 else
745 mode = 0666;
746 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
747 if (fd < 0)
748 die_errno("failed to open '%s'", path);
749 flush_buffer(fd, buf, size);
750 close(fd);
751 } else if (S_ISLNK(mode)) {
752 char *lnk = xmemdupz(buf, size);
753 safe_create_leading_directories_const(path);
754 unlink(path);
755 if (symlink(lnk, path))
756 die_errno("failed to symlink '%s'", path);
757 free(lnk);
758 } else
759 die("do not know what to do with %06o %s '%s'",
760 mode, sha1_to_hex(sha), path);
761 free(buf);
762 }
763 update_index:
764 if (update_cache)
765 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
766 }
768 static void update_file(struct merge_options *o,
769 int clean,
770 const unsigned char *sha,
771 unsigned mode,
772 const char *path)
773 {
774 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
775 }
777 /* Low level file merging, update and removal */
779 struct merge_file_info {
780 unsigned char sha[20];
781 unsigned mode;
782 unsigned clean:1,
783 merge:1;
784 };
786 static int merge_3way(struct merge_options *o,
787 mmbuffer_t *result_buf,
788 const struct diff_filespec *one,
789 const struct diff_filespec *a,
790 const struct diff_filespec *b,
791 const char *branch1,
792 const char *branch2)
793 {
794 mmfile_t orig, src1, src2;
795 struct ll_merge_options ll_opts = {0};
796 char *base_name, *name1, *name2;
797 int merge_status;
799 ll_opts.renormalize = o->renormalize;
800 ll_opts.xdl_opts = o->xdl_opts;
802 if (o->call_depth) {
803 ll_opts.virtual_ancestor = 1;
804 ll_opts.variant = 0;
805 } else {
806 switch (o->recursive_variant) {
807 case MERGE_RECURSIVE_OURS:
808 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
809 break;
810 case MERGE_RECURSIVE_THEIRS:
811 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
812 break;
813 default:
814 ll_opts.variant = 0;
815 break;
816 }
817 }
819 if (strcmp(a->path, b->path) ||
820 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
821 base_name = o->ancestor == NULL ? NULL :
822 xstrdup(mkpath("%s:%s", o->ancestor, one->path));
823 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
824 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
825 } else {
826 base_name = o->ancestor == NULL ? NULL :
827 xstrdup(mkpath("%s", o->ancestor));
828 name1 = xstrdup(mkpath("%s", branch1));
829 name2 = xstrdup(mkpath("%s", branch2));
830 }
832 read_mmblob(&orig, one->sha1);
833 read_mmblob(&src1, a->sha1);
834 read_mmblob(&src2, b->sha1);
836 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
837 &src1, name1, &src2, name2, &ll_opts);
839 free(name1);
840 free(name2);
841 free(orig.ptr);
842 free(src1.ptr);
843 free(src2.ptr);
844 return merge_status;
845 }
847 static struct merge_file_info merge_file_1(struct merge_options *o,
848 const struct diff_filespec *one,
849 const struct diff_filespec *a,
850 const struct diff_filespec *b,
851 const char *branch1,
852 const char *branch2)
853 {
854 struct merge_file_info result;
855 result.merge = 0;
856 result.clean = 1;
858 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
859 result.clean = 0;
860 if (S_ISREG(a->mode)) {
861 result.mode = a->mode;
862 hashcpy(result.sha, a->sha1);
863 } else {
864 result.mode = b->mode;
865 hashcpy(result.sha, b->sha1);
866 }
867 } else {
868 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
869 result.merge = 1;
871 /*
872 * Merge modes
873 */
874 if (a->mode == b->mode || a->mode == one->mode)
875 result.mode = b->mode;
876 else {
877 result.mode = a->mode;
878 if (b->mode != one->mode) {
879 result.clean = 0;
880 result.merge = 1;
881 }
882 }
884 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
885 hashcpy(result.sha, b->sha1);
886 else if (sha_eq(b->sha1, one->sha1))
887 hashcpy(result.sha, a->sha1);
888 else if (S_ISREG(a->mode)) {
889 mmbuffer_t result_buf;
890 int merge_status;
892 merge_status = merge_3way(o, &result_buf, one, a, b,
893 branch1, branch2);
895 if ((merge_status < 0) || !result_buf.ptr)
896 die("Failed to execute internal merge");
898 if (write_sha1_file(result_buf.ptr, result_buf.size,
899 blob_type, result.sha))
900 die("Unable to add %s to database",
901 a->path);
903 free(result_buf.ptr);
904 result.clean = (merge_status == 0);
905 } else if (S_ISGITLINK(a->mode)) {
906 result.clean = merge_submodule(result.sha, one->path, one->sha1,
907 a->sha1, b->sha1);
908 } else if (S_ISLNK(a->mode)) {
909 hashcpy(result.sha, a->sha1);
911 if (!sha_eq(a->sha1, b->sha1))
912 result.clean = 0;
913 } else {
914 die("unsupported object type in the tree");
915 }
916 }
918 return result;
919 }
921 static struct merge_file_info merge_file(struct merge_options *o,
922 const char *path,
923 const unsigned char *o_sha, int o_mode,
924 const unsigned char *a_sha, int a_mode,
925 const unsigned char *b_sha, int b_mode,
926 const char *branch1,
927 const char *branch2)
928 {
929 struct diff_filespec one, a, b;
931 one.path = a.path = b.path = (char *)path;
932 hashcpy(one.sha1, o_sha);
933 one.mode = o_mode;
934 hashcpy(a.sha1, a_sha);
935 a.mode = a_mode;
936 hashcpy(b.sha1, b_sha);
937 b.mode = b_mode;
938 return merge_file_1(o, &one, &a, &b, branch1, branch2);
939 }
941 static void conflict_rename_delete(struct merge_options *o,
942 struct diff_filepair *pair,
943 const char *rename_branch,
944 const char *other_branch)
945 {
946 char *dest_name = pair->two->path;
947 int df_conflict = 0;
949 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
950 "and deleted in %s",
951 pair->one->path, pair->two->path, rename_branch,
952 other_branch);
953 if (!o->call_depth)
954 update_stages(dest_name, NULL,
955 rename_branch == o->branch1 ? pair->two : NULL,
956 rename_branch == o->branch1 ? NULL : pair->two);
957 if (dir_in_way(dest_name, !o->call_depth)) {
958 dest_name = unique_path(o, dest_name, rename_branch);
959 df_conflict = 1;
960 }
961 update_file(o, 0, pair->two->sha1, pair->two->mode, dest_name);
962 if (df_conflict)
963 free(dest_name);
964 }
966 static void conflict_rename_rename_1to2(struct merge_options *o,
967 struct rename_conflict_info *ci)
968 {
969 /* One file was renamed in both branches, but to different names. */
970 struct diff_filespec *one = ci->pair1->one;
971 struct diff_filespec *a = ci->pair1->two;
972 struct diff_filespec *b = ci->pair2->two;
973 const char *dst_name_a = a->path;
974 const char *dst_name_b = b->path;
975 char *del[2];
976 int delp = 0;
978 output(o, 1, "CONFLICT (rename/rename): "
979 "Rename \"%s\"->\"%s\" in branch \"%s\" "
980 "rename \"%s\"->\"%s\" in \"%s\"%s",
981 one->path, a->path, ci->branch1,
982 one->path, b->path, ci->branch2,
983 o->call_depth ? " (left unresolved)" : "");
984 if (dir_in_way(a->path, !o->call_depth)) {
985 dst_name_a = del[delp++] = unique_path(o, a->path, ci->branch1);
986 output(o, 1, "%s is a directory in %s adding as %s instead",
987 a->path, ci->branch2, dst_name_a);
988 }
989 if (dir_in_way(b->path, !o->call_depth)) {
990 dst_name_b = del[delp++] = unique_path(o, b->path, ci->branch2);
991 output(o, 1, "%s is a directory in %s adding as %s instead",
992 b->path, ci->branch1, dst_name_b);
993 }
994 if (o->call_depth) {
995 struct merge_file_info mfi;
996 mfi = merge_file(o, one->path,
997 one->sha1, one->mode,
998 a->sha1, a->mode,
999 b->sha1, b->mode,
1000 ci->branch1, ci->branch2);
1001 /*
1002 * FIXME: For rename/add-source conflicts (if we could detect
1003 * such), this is wrong. We should instead find a unique
1004 * pathname and then either rename the add-source file to that
1005 * unique path, or use that unique path instead of src here.
1006 */
1007 update_file(o, 0, mfi.sha, mfi.mode, one->path);
1008 remove_file_from_cache(a->path);
1009 remove_file_from_cache(b->path);
1010 } else {
1011 update_stages(a->path, NULL, a, NULL);
1012 update_stages(b->path, NULL, NULL, b);
1014 update_file(o, 0, a->sha1, a->mode, dst_name_a);
1015 update_file(o, 0, b->sha1, b->mode, dst_name_b);
1016 }
1017 while (delp--)
1018 free(del[delp]);
1019 }
1021 static void conflict_rename_rename_2to1(struct merge_options *o,
1022 struct rename *ren1,
1023 const char *branch1,
1024 struct rename *ren2,
1025 const char *branch2)
1026 {
1027 char *path = ren1->pair->two->path; /* same as ren2->pair->two->path */
1028 /* Two files were renamed to the same thing. */
1029 if (o->call_depth) {
1030 struct merge_file_info mfi;
1031 mfi = merge_file(o, path, null_sha1, 0,
1032 ren1->pair->two->sha1, ren1->pair->two->mode,
1033 ren2->pair->two->sha1, ren2->pair->two->mode,
1034 branch1, branch2);
1035 output(o, 1, "Adding merged %s", path);
1036 update_file(o, 0, mfi.sha, mfi.mode, path);
1037 } else {
1038 char *new_path1 = unique_path(o, path, branch1);
1039 char *new_path2 = unique_path(o, path, branch2);
1040 output(o, 1, "Renaming %s to %s and %s to %s instead",
1041 ren1->pair->one->path, new_path1,
1042 ren2->pair->one->path, new_path2);
1043 remove_file(o, 0, path, 0);
1044 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode,
1045 new_path1);
1046 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode,
1047 new_path2);
1048 free(new_path2);
1049 free(new_path1);
1050 }
1051 }
1053 static int process_renames(struct merge_options *o,
1054 struct string_list *a_renames,
1055 struct string_list *b_renames)
1056 {
1057 int clean_merge = 1, i, j;
1058 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
1059 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
1060 const struct rename *sre;
1062 for (i = 0; i < a_renames->nr; i++) {
1063 sre = a_renames->items[i].util;
1064 string_list_insert(&a_by_dst, sre->pair->two->path)->util
1065 = (void *)sre;
1066 }
1067 for (i = 0; i < b_renames->nr; i++) {
1068 sre = b_renames->items[i].util;
1069 string_list_insert(&b_by_dst, sre->pair->two->path)->util
1070 = (void *)sre;
1071 }
1073 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1074 struct string_list *renames1, *renames2Dst;
1075 struct rename *ren1 = NULL, *ren2 = NULL;
1076 const char *branch1, *branch2;
1077 const char *ren1_src, *ren1_dst;
1079 if (i >= a_renames->nr) {
1080 ren2 = b_renames->items[j++].util;
1081 } else if (j >= b_renames->nr) {
1082 ren1 = a_renames->items[i++].util;
1083 } else {
1084 int compare = strcmp(a_renames->items[i].string,
1085 b_renames->items[j].string);
1086 if (compare <= 0)
1087 ren1 = a_renames->items[i++].util;
1088 if (compare >= 0)
1089 ren2 = b_renames->items[j++].util;
1090 }
1092 /* TODO: refactor, so that 1/2 are not needed */
1093 if (ren1) {
1094 renames1 = a_renames;
1095 renames2Dst = &b_by_dst;
1096 branch1 = o->branch1;
1097 branch2 = o->branch2;
1098 } else {
1099 struct rename *tmp;
1100 renames1 = b_renames;
1101 renames2Dst = &a_by_dst;
1102 branch1 = o->branch2;
1103 branch2 = o->branch1;
1104 tmp = ren2;
1105 ren2 = ren1;
1106 ren1 = tmp;
1107 }
1109 ren1->dst_entry->processed = 1;
1110 /* BUG: We should only mark src_entry as processed if we
1111 * are not dealing with a rename + add-source case.
1112 */
1113 ren1->src_entry->processed = 1;
1115 if (ren1->processed)
1116 continue;
1117 ren1->processed = 1;
1119 ren1_src = ren1->pair->one->path;
1120 ren1_dst = ren1->pair->two->path;
1122 if (ren2) {
1123 const char *ren2_src = ren2->pair->one->path;
1124 const char *ren2_dst = ren2->pair->two->path;
1125 enum rename_type rename_type;
1126 /* Renamed in 1 and renamed in 2 */
1127 if (strcmp(ren1_src, ren2_src) != 0)
1128 die("ren1.src != ren2.src");
1129 ren2->dst_entry->processed = 1;
1130 ren2->processed = 1;
1131 if (strcmp(ren1_dst, ren2_dst) != 0) {
1132 rename_type = RENAME_ONE_FILE_TO_TWO;
1133 } else {
1134 rename_type = RENAME_ONE_FILE_TO_ONE;
1135 /* BUG: We should only remove ren1_src in
1136 * the base stage (think of rename +
1137 * add-source cases).
1138 */
1139 remove_file(o, 1, ren1_src, 1);
1140 update_entry(ren1->dst_entry,
1141 ren1->pair->one,
1142 ren1->pair->two,
1143 ren2->pair->two);
1144 }
1145 setup_rename_conflict_info(rename_type,
1146 ren1->pair,
1147 ren2->pair,
1148 branch1,
1149 branch2,
1150 ren1->dst_entry,
1151 ren2->dst_entry);
1152 } else {
1153 /* Renamed in 1, maybe changed in 2 */
1154 struct string_list_item *item;
1155 /* we only use sha1 and mode of these */
1156 struct diff_filespec src_other, dst_other;
1157 int try_merge;
1159 /*
1160 * unpack_trees loads entries from common-commit
1161 * into stage 1, from head-commit into stage 2, and
1162 * from merge-commit into stage 3. We keep track
1163 * of which side corresponds to the rename.
1164 */
1165 int renamed_stage = a_renames == renames1 ? 2 : 3;
1166 int other_stage = a_renames == renames1 ? 3 : 2;
1168 /* BUG: We should only remove ren1_src in the base
1169 * stage and in other_stage (think of rename +
1170 * add-source case).
1171 */
1172 remove_file(o, 1, ren1_src,
1173 renamed_stage == 2 || !was_tracked(ren1_src));
1175 hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
1176 src_other.mode = ren1->src_entry->stages[other_stage].mode;
1177 hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
1178 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1179 try_merge = 0;
1181 if (sha_eq(src_other.sha1, null_sha1)) {
1182 setup_rename_conflict_info(RENAME_DELETE,
1183 ren1->pair,
1184 NULL,
1185 branch1,
1186 branch2,
1187 ren1->dst_entry,
1188 NULL);
1189 } else if ((item = string_list_lookup(renames2Dst, ren1_dst))) {
1190 char *ren2_src, *ren2_dst;
1191 ren2 = item->util;
1192 ren2_src = ren2->pair->one->path;
1193 ren2_dst = ren2->pair->two->path;
1195 clean_merge = 0;
1196 ren2->processed = 1;
1197 remove_file(o, 1, ren2_src,
1198 renamed_stage == 3 || would_lose_untracked(ren1_src));
1200 output(o, 1, "CONFLICT (rename/rename): "
1201 "Rename %s->%s in %s. "
1202 "Rename %s->%s in %s",
1203 ren1_src, ren1_dst, branch1,
1204 ren2_src, ren2_dst, branch2);
1205 conflict_rename_rename_2to1(o, ren1, branch1, ren2, branch2);
1206 } else if ((dst_other.mode == ren1->pair->two->mode) &&
1207 sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
1208 /* Added file on the other side
1209 identical to the file being
1210 renamed: clean merge */
1211 update_file(o, 1, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
1212 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1213 clean_merge = 0;
1214 try_merge = 1;
1215 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
1216 "%s added in %s",
1217 ren1_src, ren1_dst, branch1,
1218 ren1_dst, branch2);
1219 if (o->call_depth) {
1220 struct merge_file_info mfi;
1221 mfi = merge_file(o, ren1_dst, null_sha1, 0,
1222 ren1->pair->two->sha1, ren1->pair->two->mode,
1223 dst_other.sha1, dst_other.mode,
1224 branch1, branch2);
1225 output(o, 1, "Adding merged %s", ren1_dst);
1226 update_file(o, 0, mfi.sha, mfi.mode, ren1_dst);
1227 try_merge = 0;
1228 } else {
1229 char *new_path = unique_path(o, ren1_dst, branch2);
1230 output(o, 1, "Adding as %s instead", new_path);
1231 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
1232 free(new_path);
1233 }
1234 } else
1235 try_merge = 1;
1237 if (try_merge) {
1238 struct diff_filespec *one, *a, *b;
1239 src_other.path = (char *)ren1_src;
1241 one = ren1->pair->one;
1242 if (a_renames == renames1) {
1243 a = ren1->pair->two;
1244 b = &src_other;
1245 } else {
1246 b = ren1->pair->two;
1247 a = &src_other;
1248 }
1249 update_entry(ren1->dst_entry, one, a, b);
1250 setup_rename_conflict_info(RENAME_NORMAL,
1251 ren1->pair,
1252 NULL,
1253 branch1,
1254 NULL,
1255 ren1->dst_entry,
1256 NULL);
1257 }
1258 }
1259 }
1260 string_list_clear(&a_by_dst, 0);
1261 string_list_clear(&b_by_dst, 0);
1263 return clean_merge;
1264 }
1266 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1267 {
1268 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1269 }
1271 static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1272 {
1273 void *buf;
1274 enum object_type type;
1275 unsigned long size;
1276 buf = read_sha1_file(sha1, &type, &size);
1277 if (!buf)
1278 return error("cannot read object %s", sha1_to_hex(sha1));
1279 if (type != OBJ_BLOB) {
1280 free(buf);
1281 return error("object %s is not a blob", sha1_to_hex(sha1));
1282 }
1283 strbuf_attach(dst, buf, size, size + 1);
1284 return 0;
1285 }
1287 static int blob_unchanged(const unsigned char *o_sha,
1288 const unsigned char *a_sha,
1289 int renormalize, const char *path)
1290 {
1291 struct strbuf o = STRBUF_INIT;
1292 struct strbuf a = STRBUF_INIT;
1293 int ret = 0; /* assume changed for safety */
1295 if (sha_eq(o_sha, a_sha))
1296 return 1;
1297 if (!renormalize)
1298 return 0;
1300 assert(o_sha && a_sha);
1301 if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1302 goto error_return;
1303 /*
1304 * Note: binary | is used so that both renormalizations are
1305 * performed. Comparison can be skipped if both files are
1306 * unchanged since their sha1s have already been compared.
1307 */
1308 if (renormalize_buffer(path, o.buf, o.len, &o) |
1309 renormalize_buffer(path, a.buf, o.len, &a))
1310 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1312 error_return:
1313 strbuf_release(&o);
1314 strbuf_release(&a);
1315 return ret;
1316 }
1318 static void handle_delete_modify(struct merge_options *o,
1319 const char *path,
1320 unsigned char *o_sha, int o_mode,
1321 unsigned char *a_sha, int a_mode,
1322 unsigned char *b_sha, int b_mode)
1323 {
1324 char *renamed = NULL;
1325 if (dir_in_way(path, !o->call_depth)) {
1326 renamed = unique_path(o, path, a_sha ? o->branch1 : o->branch2);
1327 }
1329 if (o->call_depth) {
1330 /*
1331 * We cannot arbitrarily accept either a_sha or b_sha as
1332 * correct; since there is no true "middle point" between
1333 * them, simply reuse the base version for virtual merge base.
1334 */
1335 remove_file_from_cache(path);
1336 update_file(o, 0, o_sha, o_mode, renamed ? renamed : path);
1337 } else if (!a_sha) {
1338 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1339 "and modified in %s. Version %s of %s left in tree%s%s.",
1340 path, o->branch1,
1341 o->branch2, o->branch2, path,
1342 NULL == renamed ? "" : " at ",
1343 NULL == renamed ? "" : renamed);
1344 update_file(o, 0, b_sha, b_mode, renamed ? renamed : path);
1345 } else {
1346 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1347 "and modified in %s. Version %s of %s left in tree%s%s.",
1348 path, o->branch2,
1349 o->branch1, o->branch1, path,
1350 NULL == renamed ? "" : " at ",
1351 NULL == renamed ? "" : renamed);
1352 update_file(o, 0, a_sha, a_mode, renamed ? renamed : path);
1353 }
1354 free(renamed);
1356 }
1358 static int merge_content(struct merge_options *o,
1359 const char *path,
1360 unsigned char *o_sha, int o_mode,
1361 unsigned char *a_sha, int a_mode,
1362 unsigned char *b_sha, int b_mode,
1363 struct rename_conflict_info *rename_conflict_info)
1364 {
1365 const char *reason = "content";
1366 char *side1 = NULL, *side2 = NULL;
1367 const char *path1 = NULL, *path2 = NULL;
1368 struct merge_file_info mfi;
1369 struct diff_filespec one, a, b;
1370 unsigned df_conflict_remains = 0;
1372 if (!o_sha) {
1373 reason = "add/add";
1374 o_sha = (unsigned char *)null_sha1;
1375 }
1376 one.path = a.path = b.path = (char *)path;
1377 hashcpy(one.sha1, o_sha);
1378 one.mode = o_mode;
1379 hashcpy(a.sha1, a_sha);
1380 a.mode = a_mode;
1381 hashcpy(b.sha1, b_sha);
1382 b.mode = b_mode;
1384 if (rename_conflict_info) {
1385 struct diff_filepair *pair1 = rename_conflict_info->pair1;
1387 path1 = (o->branch1 == rename_conflict_info->branch1) ?
1388 pair1->two->path : pair1->one->path;
1389 /* If rename_conflict_info->pair2 != NULL, we are in
1390 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
1391 * normal rename.
1392 */
1393 path2 = (rename_conflict_info->pair2 ||
1394 o->branch2 == rename_conflict_info->branch1) ?
1395 pair1->two->path : pair1->one->path;
1396 side1 = xmalloc(strlen(o->branch1) + strlen(path1) + 2);
1397 side2 = xmalloc(strlen(o->branch2) + strlen(path2) + 2);
1398 sprintf(side1, "%s:%s", o->branch1, path1);
1399 sprintf(side2, "%s:%s", o->branch2, path2);
1401 if (dir_in_way(path, !o->call_depth))
1402 df_conflict_remains = 1;
1403 }
1404 mfi = merge_file_1(o, &one, &a, &b,
1405 side1 ? side1 : o->branch1, side2 ? side2 : o->branch2);
1406 free(side1);
1407 free(side2);
1409 if (mfi.clean && !df_conflict_remains &&
1410 sha_eq(mfi.sha, a_sha) && mfi.mode == a_mode) {
1411 int path_renamed_outside_HEAD;
1412 output(o, 3, "Skipped %s (merged same as existing)", path);
1413 /*
1414 * The content merge resulted in the same file contents we
1415 * already had. We can return early if those file contents
1416 * are recorded at the correct path (which may not be true
1417 * if the merge involves a rename).
1418 */
1419 path_renamed_outside_HEAD = !path2 || !strcmp(path, path2);
1420 if (!path_renamed_outside_HEAD) {
1421 add_cacheinfo(mfi.mode, mfi.sha, path,
1422 0 /*stage*/, 1 /*refresh*/, 0 /*options*/);
1423 return mfi.clean;
1424 }
1425 } else
1426 output(o, 2, "Auto-merging %s", path);
1428 if (!mfi.clean) {
1429 if (S_ISGITLINK(mfi.mode))
1430 reason = "submodule";
1431 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1432 reason, path);
1433 if (rename_conflict_info && !df_conflict_remains)
1434 update_stages(path, &one, &a, &b);
1435 }
1437 if (df_conflict_remains) {
1438 char *new_path;
1439 if (o->call_depth) {
1440 remove_file_from_cache(path);
1441 } else {
1442 if (!mfi.clean)
1443 update_stages(path, &one, &a, &b);
1444 else {
1445 int file_from_stage2 = was_tracked(path);
1446 struct diff_filespec merged;
1447 hashcpy(merged.sha1, mfi.sha);
1448 merged.mode = mfi.mode;
1450 update_stages(path, NULL,
1451 file_from_stage2 ? &merged : NULL,
1452 file_from_stage2 ? NULL : &merged);
1453 }
1455 }
1456 new_path = unique_path(o, path, rename_conflict_info->branch1);
1457 output(o, 1, "Adding as %s instead", new_path);
1458 update_file(o, 0, mfi.sha, mfi.mode, new_path);
1459 free(new_path);
1460 mfi.clean = 0;
1461 } else {
1462 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1463 }
1464 return mfi.clean;
1466 }
1468 /* Per entry merge function */
1469 static int process_entry(struct merge_options *o,
1470 const char *path, struct stage_data *entry)
1471 {
1472 /*
1473 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1474 print_index_entry("\tpath: ", entry);
1475 */
1476 int clean_merge = 1;
1477 int normalize = o->renormalize;
1478 unsigned o_mode = entry->stages[1].mode;
1479 unsigned a_mode = entry->stages[2].mode;
1480 unsigned b_mode = entry->stages[3].mode;
1481 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1482 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1483 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1485 entry->processed = 1;
1486 if (entry->rename_conflict_info) {
1487 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
1488 switch (conflict_info->rename_type) {
1489 case RENAME_NORMAL:
1490 case RENAME_ONE_FILE_TO_ONE:
1491 clean_merge = merge_content(o, path,
1492 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1493 conflict_info);
1494 break;
1495 case RENAME_DELETE:
1496 clean_merge = 0;
1497 conflict_rename_delete(o, conflict_info->pair1,
1498 conflict_info->branch1,
1499 conflict_info->branch2);
1500 break;
1501 case RENAME_ONE_FILE_TO_TWO:
1502 clean_merge = 0;
1503 conflict_rename_rename_1to2(o, conflict_info);
1504 break;
1505 default:
1506 entry->processed = 0;
1507 break;
1508 }
1509 } else if (o_sha && (!a_sha || !b_sha)) {
1510 /* Case A: Deleted in one */
1511 if ((!a_sha && !b_sha) ||
1512 (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1513 (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1514 /* Deleted in both or deleted in one and
1515 * unchanged in the other */
1516 if (a_sha)
1517 output(o, 2, "Removing %s", path);
1518 /* do not touch working file if it did not exist */
1519 remove_file(o, 1, path, !a_sha);
1520 } else {
1521 /* Modify/delete; deleted side may have put a directory in the way */
1522 clean_merge = 0;
1523 handle_delete_modify(o, path, o_sha, o_mode,
1524 a_sha, a_mode, b_sha, b_mode);
1525 }
1526 } else if ((!o_sha && a_sha && !b_sha) ||
1527 (!o_sha && !a_sha && b_sha)) {
1528 /* Case B: Added in one. */
1529 /* [nothing|directory] -> ([nothing|directory], file) */
1531 const char *add_branch;
1532 const char *other_branch;
1533 unsigned mode;
1534 const unsigned char *sha;
1535 const char *conf;
1537 if (a_sha) {
1538 add_branch = o->branch1;
1539 other_branch = o->branch2;
1540 mode = a_mode;
1541 sha = a_sha;
1542 conf = "file/directory";
1543 } else {
1544 add_branch = o->branch2;
1545 other_branch = o->branch1;
1546 mode = b_mode;
1547 sha = b_sha;
1548 conf = "directory/file";
1549 }
1550 if (dir_in_way(path, !o->call_depth)) {
1551 char *new_path = unique_path(o, path, add_branch);
1552 clean_merge = 0;
1553 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1554 "Adding %s as %s",
1555 conf, path, other_branch, path, new_path);
1556 if (o->call_depth)
1557 remove_file_from_cache(path);
1558 update_file(o, 0, sha, mode, new_path);
1559 if (o->call_depth)
1560 remove_file_from_cache(path);
1561 free(new_path);
1562 } else {
1563 output(o, 2, "Adding %s", path);
1564 update_file(o, 1, sha, mode, path);
1565 }
1566 } else if (a_sha && b_sha) {
1567 /* Case C: Added in both (check for same permissions) and */
1568 /* case D: Modified in both, but differently. */
1569 clean_merge = merge_content(o, path,
1570 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1571 NULL);
1572 } else if (!o_sha && !a_sha && !b_sha) {
1573 /*
1574 * this entry was deleted altogether. a_mode == 0 means
1575 * we had that path and want to actively remove it.
1576 */
1577 remove_file(o, 1, path, !a_mode);
1578 } else
1579 die("Fatal merge failure, shouldn't happen.");
1581 return clean_merge;
1582 }
1584 int merge_trees(struct merge_options *o,
1585 struct tree *head,
1586 struct tree *merge,
1587 struct tree *common,
1588 struct tree **result)
1589 {
1590 int code, clean;
1592 if (o->subtree_shift) {
1593 merge = shift_tree_object(head, merge, o->subtree_shift);
1594 common = shift_tree_object(head, common, o->subtree_shift);
1595 }
1597 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1598 output(o, 0, "Already up-to-date!");
1599 *result = head;
1600 return 1;
1601 }
1603 code = git_merge_trees(o->call_depth, common, head, merge);
1605 if (code != 0) {
1606 if (show(o, 4) || o->call_depth)
1607 die("merging of trees %s and %s failed",
1608 sha1_to_hex(head->object.sha1),
1609 sha1_to_hex(merge->object.sha1));
1610 else
1611 exit(128);
1612 }
1614 if (unmerged_cache()) {
1615 struct string_list *entries, *re_head, *re_merge;
1616 int i;
1617 string_list_clear(&o->current_file_set, 1);
1618 string_list_clear(&o->current_directory_set, 1);
1619 get_files_dirs(o, head);
1620 get_files_dirs(o, merge);
1622 entries = get_unmerged();
1623 record_df_conflict_files(o, entries);
1624 re_head = get_renames(o, head, common, head, merge, entries);
1625 re_merge = get_renames(o, merge, common, head, merge, entries);
1626 clean = process_renames(o, re_head, re_merge);
1627 for (i = entries->nr-1; 0 <= i; i--) {
1628 const char *path = entries->items[i].string;
1629 struct stage_data *e = entries->items[i].util;
1630 if (!e->processed
1631 && !process_entry(o, path, e))
1632 clean = 0;
1633 }
1634 for (i = 0; i < entries->nr; i++) {
1635 struct stage_data *e = entries->items[i].util;
1636 if (!e->processed)
1637 die("Unprocessed path??? %s",
1638 entries->items[i].string);
1639 }
1641 string_list_clear(re_merge, 0);
1642 string_list_clear(re_head, 0);
1643 string_list_clear(entries, 1);
1645 }
1646 else
1647 clean = 1;
1649 if (o->call_depth)
1650 *result = write_tree_from_memory(o);
1652 return clean;
1653 }
1655 static struct commit_list *reverse_commit_list(struct commit_list *list)
1656 {
1657 struct commit_list *next = NULL, *current, *backup;
1658 for (current = list; current; current = backup) {
1659 backup = current->next;
1660 current->next = next;
1661 next = current;
1662 }
1663 return next;
1664 }
1666 /*
1667 * Merge the commits h1 and h2, return the resulting virtual
1668 * commit object and a flag indicating the cleanness of the merge.
1669 */
1670 int merge_recursive(struct merge_options *o,
1671 struct commit *h1,
1672 struct commit *h2,
1673 struct commit_list *ca,
1674 struct commit **result)
1675 {
1676 struct commit_list *iter;
1677 struct commit *merged_common_ancestors;
1678 struct tree *mrtree = mrtree;
1679 int clean;
1681 if (show(o, 4)) {
1682 output(o, 4, "Merging:");
1683 output_commit_title(o, h1);
1684 output_commit_title(o, h2);
1685 }
1687 if (!ca) {
1688 ca = get_merge_bases(h1, h2, 1);
1689 ca = reverse_commit_list(ca);
1690 }
1692 if (show(o, 5)) {
1693 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1694 for (iter = ca; iter; iter = iter->next)
1695 output_commit_title(o, iter->item);
1696 }
1698 merged_common_ancestors = pop_commit(&ca);
1699 if (merged_common_ancestors == NULL) {
1700 /* if there is no common ancestor, make an empty tree */
1701 struct tree *tree = xcalloc(1, sizeof(struct tree));
1703 tree->object.parsed = 1;
1704 tree->object.type = OBJ_TREE;
1705 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1706 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1707 }
1709 for (iter = ca; iter; iter = iter->next) {
1710 const char *saved_b1, *saved_b2;
1711 o->call_depth++;
1712 /*
1713 * When the merge fails, the result contains files
1714 * with conflict markers. The cleanness flag is
1715 * ignored, it was never actually used, as result of
1716 * merge_trees has always overwritten it: the committed
1717 * "conflicts" were already resolved.
1718 */
1719 discard_cache();
1720 saved_b1 = o->branch1;
1721 saved_b2 = o->branch2;
1722 o->branch1 = "Temporary merge branch 1";
1723 o->branch2 = "Temporary merge branch 2";
1724 merge_recursive(o, merged_common_ancestors, iter->item,
1725 NULL, &merged_common_ancestors);
1726 o->branch1 = saved_b1;
1727 o->branch2 = saved_b2;
1728 o->call_depth--;
1730 if (!merged_common_ancestors)
1731 die("merge returned no commit");
1732 }
1734 discard_cache();
1735 if (!o->call_depth)
1736 read_cache();
1738 o->ancestor = "merged common ancestors";
1739 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1740 &mrtree);
1742 if (o->call_depth) {
1743 *result = make_virtual_commit(mrtree, "merged tree");
1744 commit_list_insert(h1, &(*result)->parents);
1745 commit_list_insert(h2, &(*result)->parents->next);
1746 }
1747 flush_output(o);
1748 if (show(o, 2))
1749 diff_warn_rename_limit("merge.renamelimit",
1750 o->needed_rename_limit, 0);
1751 return clean;
1752 }
1754 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1755 {
1756 struct object *object;
1758 object = deref_tag(parse_object(sha1), name, strlen(name));
1759 if (!object)
1760 return NULL;
1761 if (object->type == OBJ_TREE)
1762 return make_virtual_commit((struct tree*)object, name);
1763 if (object->type != OBJ_COMMIT)
1764 return NULL;
1765 if (parse_commit((struct commit *)object))
1766 return NULL;
1767 return (struct commit *)object;
1768 }
1770 int merge_recursive_generic(struct merge_options *o,
1771 const unsigned char *head,
1772 const unsigned char *merge,
1773 int num_base_list,
1774 const unsigned char **base_list,
1775 struct commit **result)
1776 {
1777 int clean, index_fd;
1778 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1779 struct commit *head_commit = get_ref(head, o->branch1);
1780 struct commit *next_commit = get_ref(merge, o->branch2);
1781 struct commit_list *ca = NULL;
1783 if (base_list) {
1784 int i;
1785 for (i = 0; i < num_base_list; ++i) {
1786 struct commit *base;
1787 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1788 return error("Could not parse object '%s'",
1789 sha1_to_hex(base_list[i]));
1790 commit_list_insert(base, &ca);
1791 }
1792 }
1794 index_fd = hold_locked_index(lock, 1);
1795 clean = merge_recursive(o, head_commit, next_commit, ca,
1796 result);
1797 if (active_cache_changed &&
1798 (write_cache(index_fd, active_cache, active_nr) ||
1799 commit_locked_index(lock)))
1800 return error("Unable to write index.");
1802 return clean ? 0 : 1;
1803 }
1805 static int merge_recursive_config(const char *var, const char *value, void *cb)
1806 {
1807 struct merge_options *o = cb;
1808 if (!strcmp(var, "merge.verbosity")) {
1809 o->verbosity = git_config_int(var, value);
1810 return 0;
1811 }
1812 if (!strcmp(var, "diff.renamelimit")) {
1813 o->diff_rename_limit = git_config_int(var, value);
1814 return 0;
1815 }
1816 if (!strcmp(var, "merge.renamelimit")) {
1817 o->merge_rename_limit = git_config_int(var, value);
1818 return 0;
1819 }
1820 return git_xmerge_config(var, value, cb);
1821 }
1823 void init_merge_options(struct merge_options *o)
1824 {
1825 memset(o, 0, sizeof(struct merge_options));
1826 o->verbosity = 2;
1827 o->buffer_output = 1;
1828 o->diff_rename_limit = -1;
1829 o->merge_rename_limit = -1;
1830 o->renormalize = 0;
1831 git_config(merge_recursive_config, o);
1832 if (getenv("GIT_MERGE_VERBOSITY"))
1833 o->verbosity =
1834 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1835 if (o->verbosity >= 5)
1836 o->buffer_output = 0;
1837 strbuf_init(&o->obuf, 0);
1838 memset(&o->current_file_set, 0, sizeof(struct string_list));
1839 o->current_file_set.strdup_strings = 1;
1840 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1841 o->current_directory_set.strdup_strings = 1;
1842 memset(&o->df_conflict_file_set, 0, sizeof(struct string_list));
1843 o->df_conflict_file_set.strdup_strings = 1;
1844 }
1846 int parse_merge_opt(struct merge_options *o, const char *s)
1847 {
1848 if (!s || !*s)
1849 return -1;
1850 if (!strcmp(s, "ours"))
1851 o->recursive_variant = MERGE_RECURSIVE_OURS;
1852 else if (!strcmp(s, "theirs"))
1853 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
1854 else if (!strcmp(s, "subtree"))
1855 o->subtree_shift = "";
1856 else if (!prefixcmp(s, "subtree="))
1857 o->subtree_shift = s + strlen("subtree=");
1858 else if (!strcmp(s, "patience"))
1859 o->xdl_opts |= XDF_PATIENCE_DIFF;
1860 else if (!strcmp(s, "ignore-space-change"))
1861 o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1862 else if (!strcmp(s, "ignore-all-space"))
1863 o->xdl_opts |= XDF_IGNORE_WHITESPACE;
1864 else if (!strcmp(s, "ignore-space-at-eol"))
1865 o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
1866 else if (!strcmp(s, "renormalize"))
1867 o->renormalize = 1;
1868 else if (!strcmp(s, "no-renormalize"))
1869 o->renormalize = 0;
1870 else if (!prefixcmp(s, "rename-threshold=")) {
1871 const char *score = s + strlen("rename-threshold=");
1872 if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
1873 return -1;
1874 }
1875 else
1876 return -1;
1877 return 0;
1878 }