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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_TWO
70 };
72 struct rename_df_conflict_info {
73 enum rename_type rename_type;
74 struct diff_filepair *pair1;
75 struct diff_filepair *pair2;
76 const char *branch1;
77 const char *branch2;
78 struct stage_data *dst_entry1;
79 struct stage_data *dst_entry2;
80 };
82 /*
83 * Since we want to write the index eventually, we cannot reuse the index
84 * for these (temporary) data.
85 */
86 struct stage_data {
87 struct {
88 unsigned mode;
89 unsigned char sha[20];
90 } stages[4];
91 struct rename_df_conflict_info *rename_df_conflict_info;
92 unsigned processed:1;
93 unsigned involved_in_rename:1;
94 };
96 static inline void setup_rename_df_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_df_conflict_info *ci = xcalloc(1, sizeof(struct rename_df_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_df_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_df_conflict_info = ci;
119 dst_entry2->processed = 0;
120 }
121 }
123 static int show(struct merge_options *o, int v)
124 {
125 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
126 }
128 static void flush_output(struct merge_options *o)
129 {
130 if (o->obuf.len) {
131 fputs(o->obuf.buf, stdout);
132 strbuf_reset(&o->obuf);
133 }
134 }
136 __attribute__((format (printf, 3, 4)))
137 static void output(struct merge_options *o, int v, const char *fmt, ...)
138 {
139 va_list ap;
141 if (!show(o, v))
142 return;
144 strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
145 memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
146 strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
148 va_start(ap, fmt);
149 strbuf_vaddf(&o->obuf, fmt, ap);
150 va_end(ap);
152 strbuf_add(&o->obuf, "\n", 1);
153 if (!o->buffer_output)
154 flush_output(o);
155 }
157 static void output_commit_title(struct merge_options *o, struct commit *commit)
158 {
159 int i;
160 flush_output(o);
161 for (i = o->call_depth; i--;)
162 fputs(" ", stdout);
163 if (commit->util)
164 printf("virtual %s\n", (char *)commit->util);
165 else {
166 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
167 if (parse_commit(commit) != 0)
168 printf("(bad commit)\n");
169 else {
170 const char *title;
171 int len = find_commit_subject(commit->buffer, &title);
172 if (len)
173 printf("%.*s\n", len, title);
174 }
175 }
176 }
178 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
179 const char *path, int stage, int refresh, int options)
180 {
181 struct cache_entry *ce;
182 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
183 if (!ce)
184 return error("addinfo_cache failed for path '%s'", path);
185 return add_cache_entry(ce, options);
186 }
188 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
189 {
190 parse_tree(tree);
191 init_tree_desc(desc, tree->buffer, tree->size);
192 }
194 static int git_merge_trees(int index_only,
195 struct tree *common,
196 struct tree *head,
197 struct tree *merge)
198 {
199 int rc;
200 struct tree_desc t[3];
201 struct unpack_trees_options opts;
203 memset(&opts, 0, sizeof(opts));
204 if (index_only)
205 opts.index_only = 1;
206 else
207 opts.update = 1;
208 opts.merge = 1;
209 opts.head_idx = 2;
210 opts.fn = threeway_merge;
211 opts.src_index = &the_index;
212 opts.dst_index = &the_index;
213 setup_unpack_trees_porcelain(&opts, "merge");
215 init_tree_desc_from_tree(t+0, common);
216 init_tree_desc_from_tree(t+1, head);
217 init_tree_desc_from_tree(t+2, merge);
219 rc = unpack_trees(3, t, &opts);
220 cache_tree_free(&active_cache_tree);
221 return rc;
222 }
224 struct tree *write_tree_from_memory(struct merge_options *o)
225 {
226 struct tree *result = NULL;
228 if (unmerged_cache()) {
229 int i;
230 fprintf(stderr, "BUG: There are unmerged index entries:\n");
231 for (i = 0; i < active_nr; i++) {
232 struct cache_entry *ce = active_cache[i];
233 if (ce_stage(ce))
234 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
235 (int)ce_namelen(ce), ce->name);
236 }
237 die("Bug in merge-recursive.c");
238 }
240 if (!active_cache_tree)
241 active_cache_tree = cache_tree();
243 if (!cache_tree_fully_valid(active_cache_tree) &&
244 cache_tree_update(active_cache_tree,
245 active_cache, active_nr, 0, 0) < 0)
246 die("error building trees");
248 result = lookup_tree(active_cache_tree->sha1);
250 return result;
251 }
253 static int save_files_dirs(const unsigned char *sha1,
254 const char *base, int baselen, const char *path,
255 unsigned int mode, int stage, void *context)
256 {
257 int len = strlen(path);
258 char *newpath = xmalloc(baselen + len + 1);
259 struct merge_options *o = context;
261 memcpy(newpath, base, baselen);
262 memcpy(newpath + baselen, path, len);
263 newpath[baselen + len] = '\0';
265 if (S_ISDIR(mode))
266 string_list_insert(&o->current_directory_set, newpath);
267 else
268 string_list_insert(&o->current_file_set, newpath);
269 free(newpath);
271 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
272 }
274 static int get_files_dirs(struct merge_options *o, struct tree *tree)
275 {
276 int n;
277 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
278 return 0;
279 n = o->current_file_set.nr + o->current_directory_set.nr;
280 return n;
281 }
283 /*
284 * Returns an index_entry instance which doesn't have to correspond to
285 * a real cache entry in Git's index.
286 */
287 static struct stage_data *insert_stage_data(const char *path,
288 struct tree *o, struct tree *a, struct tree *b,
289 struct string_list *entries)
290 {
291 struct string_list_item *item;
292 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
293 get_tree_entry(o->object.sha1, path,
294 e->stages[1].sha, &e->stages[1].mode);
295 get_tree_entry(a->object.sha1, path,
296 e->stages[2].sha, &e->stages[2].mode);
297 get_tree_entry(b->object.sha1, path,
298 e->stages[3].sha, &e->stages[3].mode);
299 item = string_list_insert(entries, path);
300 item->util = e;
301 return e;
302 }
304 /*
305 * Create a dictionary mapping file names to stage_data objects. The
306 * dictionary contains one entry for every path with a non-zero stage entry.
307 */
308 static struct string_list *get_unmerged(void)
309 {
310 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
311 int i;
313 unmerged->strdup_strings = 1;
315 for (i = 0; i < active_nr; i++) {
316 struct string_list_item *item;
317 struct stage_data *e;
318 struct cache_entry *ce = active_cache[i];
319 if (!ce_stage(ce))
320 continue;
322 item = string_list_lookup(unmerged, ce->name);
323 if (!item) {
324 item = string_list_insert(unmerged, ce->name);
325 item->util = xcalloc(1, sizeof(struct stage_data));
326 }
327 e = item->util;
328 e->stages[ce_stage(ce)].mode = ce->ce_mode;
329 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
330 }
332 return unmerged;
333 }
335 static int string_list_df_name_compare(const void *a, const void *b)
336 {
337 const struct string_list_item *one = a;
338 const struct string_list_item *two = b;
339 int onelen = strlen(one->string);
340 int twolen = strlen(two->string);
341 /*
342 * Here we only care that entries for D/F conflicts are
343 * adjacent, in particular with the file of the D/F conflict
344 * appearing before files below the corresponding directory.
345 * The order of the rest of the list is irrelevant for us.
346 *
347 * To achieve this, we sort with df_name_compare and provide
348 * the mode S_IFDIR so that D/F conflicts will sort correctly.
349 * We use the mode S_IFDIR for everything else for simplicity,
350 * since in other cases any changes in their order due to
351 * sorting cause no problems for us.
352 */
353 int cmp = df_name_compare(one->string, onelen, S_IFDIR,
354 two->string, twolen, S_IFDIR);
355 /*
356 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
357 * that 'foo' comes before 'foo/bar'.
358 */
359 if (cmp)
360 return cmp;
361 return onelen - twolen;
362 }
364 static void record_df_conflict_files(struct merge_options *o,
365 struct string_list *entries)
366 {
367 /* If there is a D/F conflict and the file for such a conflict
368 * currently exist in the working copy, we want to allow it to
369 * be removed to make room for the corresponding directory if
370 * needed. The files underneath the directories of such D/F
371 * conflicts will be handled in process_entry(), while the
372 * files of such D/F conflicts will be processed later in
373 * process_df_entry(). If the corresponding directory ends up
374 * being removed by the merge, then no additional work needs
375 * to be done by process_df_entry() for the conflicting file.
376 * If the directory needs to be written to the working copy,
377 * then the conflicting file will simply be removed (e.g. in
378 * make_room_for_path). If the directory is written to the
379 * working copy but the file also has a conflict that needs to
380 * be resolved, then process_df_entry() will reinstate the
381 * file with a new unique name.
382 */
383 const char *last_file = NULL;
384 int last_len = 0;
385 int i;
387 /*
388 * If we're merging merge-bases, we don't want to bother with
389 * any working directory changes.
390 */
391 if (o->call_depth)
392 return;
394 /* Ensure D/F conflicts are adjacent in the entries list. */
395 qsort(entries->items, entries->nr, sizeof(*entries->items),
396 string_list_df_name_compare);
398 string_list_clear(&o->df_conflict_file_set, 1);
399 for (i = 0; i < entries->nr; i++) {
400 const char *path = entries->items[i].string;
401 int len = strlen(path);
402 struct stage_data *e = entries->items[i].util;
404 /*
405 * Check if last_file & path correspond to a D/F conflict;
406 * i.e. whether path is last_file+'/'+<something>.
407 * If so, record that it's okay to remove last_file to make
408 * room for path and friends if needed.
409 */
410 if (last_file &&
411 len > last_len &&
412 memcmp(path, last_file, last_len) == 0 &&
413 path[last_len] == '/') {
414 string_list_insert(&o->df_conflict_file_set, last_file);
415 }
417 /*
418 * Determine whether path could exist as a file in the
419 * working directory as a possible D/F conflict. This
420 * will only occur when it exists in stage 2 as a
421 * file.
422 */
423 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
424 last_file = path;
425 last_len = len;
426 } else {
427 last_file = NULL;
428 }
429 }
430 }
432 struct rename {
433 struct diff_filepair *pair;
434 struct stage_data *src_entry;
435 struct stage_data *dst_entry;
436 unsigned processed:1;
437 };
439 /*
440 * Get information of all renames which occurred between 'o_tree' and
441 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
442 * 'b_tree') to be able to associate the correct cache entries with
443 * the rename information. 'tree' is always equal to either a_tree or b_tree.
444 */
445 static struct string_list *get_renames(struct merge_options *o,
446 struct tree *tree,
447 struct tree *o_tree,
448 struct tree *a_tree,
449 struct tree *b_tree,
450 struct string_list *entries)
451 {
452 int i;
453 struct string_list *renames;
454 struct diff_options opts;
456 renames = xcalloc(1, sizeof(struct string_list));
457 diff_setup(&opts);
458 DIFF_OPT_SET(&opts, RECURSIVE);
459 opts.detect_rename = DIFF_DETECT_RENAME;
460 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
461 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
462 1000;
463 opts.rename_score = o->rename_score;
464 opts.show_rename_progress = o->show_rename_progress;
465 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
466 if (diff_setup_done(&opts) < 0)
467 die("diff setup failed");
468 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
469 diffcore_std(&opts);
470 if (opts.needed_rename_limit > o->needed_rename_limit)
471 o->needed_rename_limit = opts.needed_rename_limit;
472 for (i = 0; i < diff_queued_diff.nr; ++i) {
473 struct string_list_item *item;
474 struct rename *re;
475 struct diff_filepair *pair = diff_queued_diff.queue[i];
476 if (pair->status != 'R') {
477 diff_free_filepair(pair);
478 continue;
479 }
480 re = xmalloc(sizeof(*re));
481 re->processed = 0;
482 re->pair = pair;
483 item = string_list_lookup(entries, re->pair->one->path);
484 if (!item)
485 re->src_entry = insert_stage_data(re->pair->one->path,
486 o_tree, a_tree, b_tree, entries);
487 else
488 re->src_entry = item->util;
490 item = string_list_lookup(entries, re->pair->two->path);
491 if (!item)
492 re->dst_entry = insert_stage_data(re->pair->two->path,
493 o_tree, a_tree, b_tree, entries);
494 else
495 re->dst_entry = item->util;
496 item = string_list_insert(renames, pair->one->path);
497 item->util = re;
498 }
499 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
500 diff_queued_diff.nr = 0;
501 diff_flush(&opts);
502 return renames;
503 }
505 static int update_stages(const char *path, const struct diff_filespec *o,
506 const struct diff_filespec *a,
507 const struct diff_filespec *b)
508 {
509 int clear = 1;
510 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
511 if (clear)
512 if (remove_file_from_cache(path))
513 return -1;
514 if (o)
515 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
516 return -1;
517 if (a)
518 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
519 return -1;
520 if (b)
521 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
522 return -1;
523 return 0;
524 }
526 static void update_entry(struct stage_data *entry,
527 struct diff_filespec *o,
528 struct diff_filespec *a,
529 struct diff_filespec *b)
530 {
531 entry->processed = 0;
532 entry->stages[1].mode = o->mode;
533 entry->stages[2].mode = a->mode;
534 entry->stages[3].mode = b->mode;
535 hashcpy(entry->stages[1].sha, o->sha1);
536 hashcpy(entry->stages[2].sha, a->sha1);
537 hashcpy(entry->stages[3].sha, b->sha1);
538 }
540 static int remove_file(struct merge_options *o, int clean,
541 const char *path, int no_wd)
542 {
543 int update_cache = o->call_depth || clean;
544 int update_working_directory = !o->call_depth && !no_wd;
546 if (update_cache) {
547 if (remove_file_from_cache(path))
548 return -1;
549 }
550 if (update_working_directory) {
551 if (remove_path(path))
552 return -1;
553 }
554 return 0;
555 }
557 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
558 {
559 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
560 int suffix = 0;
561 struct stat st;
562 char *p = newpath + strlen(path);
563 strcpy(newpath, path);
564 *(p++) = '~';
565 strcpy(p, branch);
566 for (; *p; ++p)
567 if ('/' == *p)
568 *p = '_';
569 while (string_list_has_string(&o->current_file_set, newpath) ||
570 string_list_has_string(&o->current_directory_set, newpath) ||
571 lstat(newpath, &st) == 0)
572 sprintf(p, "_%d", suffix++);
574 string_list_insert(&o->current_file_set, newpath);
575 return newpath;
576 }
578 static void flush_buffer(int fd, const char *buf, unsigned long size)
579 {
580 while (size > 0) {
581 long ret = write_in_full(fd, buf, size);
582 if (ret < 0) {
583 /* Ignore epipe */
584 if (errno == EPIPE)
585 break;
586 die_errno("merge-recursive");
587 } else if (!ret) {
588 die("merge-recursive: disk full?");
589 }
590 size -= ret;
591 buf += ret;
592 }
593 }
595 static int dir_in_way(const char *path, int check_working_copy)
596 {
597 int pos, pathlen = strlen(path);
598 char *dirpath = xmalloc(pathlen + 2);
599 struct stat st;
601 strcpy(dirpath, path);
602 dirpath[pathlen] = '/';
603 dirpath[pathlen+1] = '\0';
605 pos = cache_name_pos(dirpath, pathlen+1);
607 if (pos < 0)
608 pos = -1 - pos;
609 if (pos < active_nr &&
610 !strncmp(dirpath, active_cache[pos]->name, pathlen+1)) {
611 free(dirpath);
612 return 1;
613 }
615 free(dirpath);
616 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode);
617 }
619 static int was_tracked(const char *path)
620 {
621 int pos = cache_name_pos(path, strlen(path));
623 if (pos < 0)
624 pos = -1 - pos;
625 while (pos < active_nr &&
626 !strcmp(path, active_cache[pos]->name)) {
627 /*
628 * If stage #0, it is definitely tracked.
629 * If it has stage #2 then it was tracked
630 * before this merge started. All other
631 * cases the path was not tracked.
632 */
633 switch (ce_stage(active_cache[pos])) {
634 case 0:
635 case 2:
636 return 1;
637 }
638 pos++;
639 }
640 return 0;
641 }
643 static int would_lose_untracked(const char *path)
644 {
645 return !was_tracked(path) && file_exists(path);
646 }
648 static int make_room_for_path(struct merge_options *o, const char *path)
649 {
650 int status, i;
651 const char *msg = "failed to create path '%s'%s";
653 /* Unlink any D/F conflict files that are in the way */
654 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
655 const char *df_path = o->df_conflict_file_set.items[i].string;
656 size_t pathlen = strlen(path);
657 size_t df_pathlen = strlen(df_path);
658 if (df_pathlen < pathlen &&
659 path[df_pathlen] == '/' &&
660 strncmp(path, df_path, df_pathlen) == 0) {
661 output(o, 3,
662 "Removing %s to make room for subdirectory\n",
663 df_path);
664 unlink(df_path);
665 unsorted_string_list_delete_item(&o->df_conflict_file_set,
666 i, 0);
667 break;
668 }
669 }
671 /* Make sure leading directories are created */
672 status = safe_create_leading_directories_const(path);
673 if (status) {
674 if (status == -3) {
675 /* something else exists */
676 error(msg, path, ": perhaps a D/F conflict?");
677 return -1;
678 }
679 die(msg, path, "");
680 }
682 /*
683 * Do not unlink a file in the work tree if we are not
684 * tracking it.
685 */
686 if (would_lose_untracked(path))
687 return error("refusing to lose untracked file at '%s'",
688 path);
690 /* Successful unlink is good.. */
691 if (!unlink(path))
692 return 0;
693 /* .. and so is no existing file */
694 if (errno == ENOENT)
695 return 0;
696 /* .. but not some other error (who really cares what?) */
697 return error(msg, path, ": perhaps a D/F conflict?");
698 }
700 static void update_file_flags(struct merge_options *o,
701 const unsigned char *sha,
702 unsigned mode,
703 const char *path,
704 int update_cache,
705 int update_wd)
706 {
707 if (o->call_depth)
708 update_wd = 0;
710 if (update_wd) {
711 enum object_type type;
712 void *buf;
713 unsigned long size;
715 if (S_ISGITLINK(mode)) {
716 /*
717 * We may later decide to recursively descend into
718 * the submodule directory and update its index
719 * and/or work tree, but we do not do that now.
720 */
721 update_wd = 0;
722 goto update_index;
723 }
725 buf = read_sha1_file(sha, &type, &size);
726 if (!buf)
727 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
728 if (type != OBJ_BLOB)
729 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
730 if (S_ISREG(mode)) {
731 struct strbuf strbuf = STRBUF_INIT;
732 if (convert_to_working_tree(path, buf, size, &strbuf)) {
733 free(buf);
734 size = strbuf.len;
735 buf = strbuf_detach(&strbuf, NULL);
736 }
737 }
739 if (make_room_for_path(o, path) < 0) {
740 update_wd = 0;
741 free(buf);
742 goto update_index;
743 }
744 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
745 int fd;
746 if (mode & 0100)
747 mode = 0777;
748 else
749 mode = 0666;
750 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
751 if (fd < 0)
752 die_errno("failed to open '%s'", path);
753 flush_buffer(fd, buf, size);
754 close(fd);
755 } else if (S_ISLNK(mode)) {
756 char *lnk = xmemdupz(buf, size);
757 safe_create_leading_directories_const(path);
758 unlink(path);
759 if (symlink(lnk, path))
760 die_errno("failed to symlink '%s'", path);
761 free(lnk);
762 } else
763 die("do not know what to do with %06o %s '%s'",
764 mode, sha1_to_hex(sha), path);
765 free(buf);
766 }
767 update_index:
768 if (update_cache)
769 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
770 }
772 static void update_file(struct merge_options *o,
773 int clean,
774 const unsigned char *sha,
775 unsigned mode,
776 const char *path)
777 {
778 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
779 }
781 /* Low level file merging, update and removal */
783 struct merge_file_info {
784 unsigned char sha[20];
785 unsigned mode;
786 unsigned clean:1,
787 merge:1;
788 };
790 static int merge_3way(struct merge_options *o,
791 mmbuffer_t *result_buf,
792 const struct diff_filespec *one,
793 const struct diff_filespec *a,
794 const struct diff_filespec *b,
795 const char *branch1,
796 const char *branch2)
797 {
798 mmfile_t orig, src1, src2;
799 struct ll_merge_options ll_opts = {0};
800 char *base_name, *name1, *name2;
801 int merge_status;
803 ll_opts.renormalize = o->renormalize;
804 ll_opts.xdl_opts = o->xdl_opts;
806 if (o->call_depth) {
807 ll_opts.virtual_ancestor = 1;
808 ll_opts.variant = 0;
809 } else {
810 switch (o->recursive_variant) {
811 case MERGE_RECURSIVE_OURS:
812 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
813 break;
814 case MERGE_RECURSIVE_THEIRS:
815 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
816 break;
817 default:
818 ll_opts.variant = 0;
819 break;
820 }
821 }
823 if (strcmp(a->path, b->path) ||
824 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
825 base_name = o->ancestor == NULL ? NULL :
826 xstrdup(mkpath("%s:%s", o->ancestor, one->path));
827 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
828 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
829 } else {
830 base_name = o->ancestor == NULL ? NULL :
831 xstrdup(mkpath("%s", o->ancestor));
832 name1 = xstrdup(mkpath("%s", branch1));
833 name2 = xstrdup(mkpath("%s", branch2));
834 }
836 read_mmblob(&orig, one->sha1);
837 read_mmblob(&src1, a->sha1);
838 read_mmblob(&src2, b->sha1);
840 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
841 &src1, name1, &src2, name2, &ll_opts);
843 free(name1);
844 free(name2);
845 free(orig.ptr);
846 free(src1.ptr);
847 free(src2.ptr);
848 return merge_status;
849 }
851 static struct merge_file_info merge_file(struct merge_options *o,
852 const struct diff_filespec *one,
853 const struct diff_filespec *a,
854 const struct diff_filespec *b,
855 const char *branch1,
856 const char *branch2)
857 {
858 struct merge_file_info result;
859 result.merge = 0;
860 result.clean = 1;
862 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
863 result.clean = 0;
864 if (S_ISREG(a->mode)) {
865 result.mode = a->mode;
866 hashcpy(result.sha, a->sha1);
867 } else {
868 result.mode = b->mode;
869 hashcpy(result.sha, b->sha1);
870 }
871 } else {
872 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
873 result.merge = 1;
875 /*
876 * Merge modes
877 */
878 if (a->mode == b->mode || a->mode == one->mode)
879 result.mode = b->mode;
880 else {
881 result.mode = a->mode;
882 if (b->mode != one->mode) {
883 result.clean = 0;
884 result.merge = 1;
885 }
886 }
888 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
889 hashcpy(result.sha, b->sha1);
890 else if (sha_eq(b->sha1, one->sha1))
891 hashcpy(result.sha, a->sha1);
892 else if (S_ISREG(a->mode)) {
893 mmbuffer_t result_buf;
894 int merge_status;
896 merge_status = merge_3way(o, &result_buf, one, a, b,
897 branch1, branch2);
899 if ((merge_status < 0) || !result_buf.ptr)
900 die("Failed to execute internal merge");
902 if (write_sha1_file(result_buf.ptr, result_buf.size,
903 blob_type, result.sha))
904 die("Unable to add %s to database",
905 a->path);
907 free(result_buf.ptr);
908 result.clean = (merge_status == 0);
909 } else if (S_ISGITLINK(a->mode)) {
910 result.clean = merge_submodule(result.sha, one->path, one->sha1,
911 a->sha1, b->sha1);
912 } else if (S_ISLNK(a->mode)) {
913 hashcpy(result.sha, a->sha1);
915 if (!sha_eq(a->sha1, b->sha1))
916 result.clean = 0;
917 } else {
918 die("unsupported object type in the tree");
919 }
920 }
922 return result;
923 }
925 static void conflict_rename_delete(struct merge_options *o,
926 struct diff_filepair *pair,
927 const char *rename_branch,
928 const char *other_branch)
929 {
930 char *dest_name = pair->two->path;
931 int df_conflict = 0;
933 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
934 "and deleted in %s",
935 pair->one->path, pair->two->path, rename_branch,
936 other_branch);
937 if (!o->call_depth)
938 update_stages(dest_name, NULL,
939 rename_branch == o->branch1 ? pair->two : NULL,
940 rename_branch == o->branch1 ? NULL : pair->two);
941 if (dir_in_way(dest_name, !o->call_depth)) {
942 dest_name = unique_path(o, dest_name, rename_branch);
943 df_conflict = 1;
944 }
945 update_file(o, 0, pair->two->sha1, pair->two->mode, dest_name);
946 if (df_conflict)
947 free(dest_name);
948 }
950 static void conflict_rename_rename_1to2(struct merge_options *o,
951 struct diff_filepair *pair1,
952 const char *branch1,
953 struct diff_filepair *pair2,
954 const char *branch2)
955 {
956 /* One file was renamed in both branches, but to different names. */
957 char *del[2];
958 int delp = 0;
959 const char *ren1_dst = pair1->two->path;
960 const char *ren2_dst = pair2->two->path;
961 const char *dst_name1 = ren1_dst;
962 const char *dst_name2 = ren2_dst;
963 if (dir_in_way(ren1_dst, !o->call_depth)) {
964 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
965 output(o, 1, "%s is a directory in %s adding as %s instead",
966 ren1_dst, branch2, dst_name1);
967 }
968 if (dir_in_way(ren2_dst, !o->call_depth)) {
969 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
970 output(o, 1, "%s is a directory in %s adding as %s instead",
971 ren2_dst, branch1, dst_name2);
972 }
973 if (o->call_depth) {
974 remove_file_from_cache(dst_name1);
975 remove_file_from_cache(dst_name2);
976 /*
977 * Uncomment to leave the conflicting names in the resulting tree
978 *
979 * update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1);
980 * update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2);
981 */
982 } else {
983 update_stages(ren1_dst, NULL, pair1->two, NULL);
984 update_stages(ren2_dst, NULL, NULL, pair2->two);
986 update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1);
987 update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2);
988 }
989 while (delp--)
990 free(del[delp]);
991 }
993 static void conflict_rename_rename_2to1(struct merge_options *o,
994 struct rename *ren1,
995 const char *branch1,
996 struct rename *ren2,
997 const char *branch2)
998 {
999 char *path = ren1->pair->two->path; /* same as ren2->pair->two->path */
1000 /* Two files were renamed to the same thing. */
1001 if (o->call_depth) {
1002 struct merge_file_info mfi;
1003 struct diff_filespec one, a, b;
1005 one.path = a.path = b.path = path;
1006 hashcpy(one.sha1, null_sha1);
1007 one.mode = 0;
1008 hashcpy(a.sha1, ren1->pair->two->sha1);
1009 a.mode = ren1->pair->two->mode;
1010 hashcpy(b.sha1, ren2->pair->two->sha1);
1011 b.mode = ren2->pair->two->mode;
1012 mfi = merge_file(o, &one, &a, &b, branch1, branch2);
1013 output(o, 1, "Adding merged %s", path);
1014 update_file(o, 0, mfi.sha, mfi.mode, path);
1015 } else {
1016 char *new_path1 = unique_path(o, path, branch1);
1017 char *new_path2 = unique_path(o, path, branch2);
1018 output(o, 1, "Renaming %s to %s and %s to %s instead",
1019 ren1->pair->one->path, new_path1,
1020 ren2->pair->one->path, new_path2);
1021 remove_file(o, 0, path, 0);
1022 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode,
1023 new_path1);
1024 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode,
1025 new_path2);
1026 free(new_path2);
1027 free(new_path1);
1028 }
1029 }
1031 static int process_renames(struct merge_options *o,
1032 struct string_list *a_renames,
1033 struct string_list *b_renames)
1034 {
1035 int clean_merge = 1, i, j;
1036 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
1037 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
1038 const struct rename *sre;
1040 for (i = 0; i < a_renames->nr; i++) {
1041 sre = a_renames->items[i].util;
1042 string_list_insert(&a_by_dst, sre->pair->two->path)->util
1043 = (void *)sre;
1044 }
1045 for (i = 0; i < b_renames->nr; i++) {
1046 sre = b_renames->items[i].util;
1047 string_list_insert(&b_by_dst, sre->pair->two->path)->util
1048 = (void *)sre;
1049 }
1051 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1052 struct string_list *renames1, *renames2Dst;
1053 struct rename *ren1 = NULL, *ren2 = NULL;
1054 const char *branch1, *branch2;
1055 const char *ren1_src, *ren1_dst;
1057 if (i >= a_renames->nr) {
1058 ren2 = b_renames->items[j++].util;
1059 } else if (j >= b_renames->nr) {
1060 ren1 = a_renames->items[i++].util;
1061 } else {
1062 int compare = strcmp(a_renames->items[i].string,
1063 b_renames->items[j].string);
1064 if (compare <= 0)
1065 ren1 = a_renames->items[i++].util;
1066 if (compare >= 0)
1067 ren2 = b_renames->items[j++].util;
1068 }
1070 /* TODO: refactor, so that 1/2 are not needed */
1071 if (ren1) {
1072 renames1 = a_renames;
1073 renames2Dst = &b_by_dst;
1074 branch1 = o->branch1;
1075 branch2 = o->branch2;
1076 } else {
1077 struct rename *tmp;
1078 renames1 = b_renames;
1079 renames2Dst = &a_by_dst;
1080 branch1 = o->branch2;
1081 branch2 = o->branch1;
1082 tmp = ren2;
1083 ren2 = ren1;
1084 ren1 = tmp;
1085 }
1087 ren1->dst_entry->processed = 1;
1088 /* BUG: We should only mark src_entry as processed if we
1089 * are not dealing with a rename + add-source case.
1090 */
1091 ren1->src_entry->processed = 1;
1093 if (ren1->processed)
1094 continue;
1095 ren1->processed = 1;
1097 ren1_src = ren1->pair->one->path;
1098 ren1_dst = ren1->pair->two->path;
1100 if (ren2) {
1101 const char *ren2_src = ren2->pair->one->path;
1102 const char *ren2_dst = ren2->pair->two->path;
1103 /* Renamed in 1 and renamed in 2 */
1104 if (strcmp(ren1_src, ren2_src) != 0)
1105 die("ren1.src != ren2.src");
1106 ren2->dst_entry->processed = 1;
1107 ren2->processed = 1;
1108 if (strcmp(ren1_dst, ren2_dst) != 0) {
1109 setup_rename_df_conflict_info(RENAME_ONE_FILE_TO_TWO,
1110 ren1->pair,
1111 ren2->pair,
1112 branch1,
1113 branch2,
1114 ren1->dst_entry,
1115 ren2->dst_entry);
1116 } else {
1117 /* BUG: We should only remove ren1_src in
1118 * the base stage (think of rename +
1119 * add-source cases).
1120 */
1121 remove_file(o, 1, ren1_src, 1);
1122 update_entry(ren1->dst_entry,
1123 ren1->pair->one,
1124 ren1->pair->two,
1125 ren2->pair->two);
1126 ren1->dst_entry->involved_in_rename = 1;
1127 }
1128 } else {
1129 /* Renamed in 1, maybe changed in 2 */
1130 struct string_list_item *item;
1131 /* we only use sha1 and mode of these */
1132 struct diff_filespec src_other, dst_other;
1133 int try_merge;
1135 /*
1136 * unpack_trees loads entries from common-commit
1137 * into stage 1, from head-commit into stage 2, and
1138 * from merge-commit into stage 3. We keep track
1139 * of which side corresponds to the rename.
1140 */
1141 int renamed_stage = a_renames == renames1 ? 2 : 3;
1142 int other_stage = a_renames == renames1 ? 3 : 2;
1144 /* BUG: We should only remove ren1_src in the base
1145 * stage and in other_stage (think of rename +
1146 * add-source case).
1147 */
1148 remove_file(o, 1, ren1_src,
1149 renamed_stage == 2 || !was_tracked(ren1_src));
1151 hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
1152 src_other.mode = ren1->src_entry->stages[other_stage].mode;
1153 hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
1154 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1155 try_merge = 0;
1157 if (sha_eq(src_other.sha1, null_sha1)) {
1158 if (dir_in_way(ren1_dst, 0 /*check_wc*/)) {
1159 ren1->dst_entry->processed = 0;
1160 setup_rename_df_conflict_info(RENAME_DELETE,
1161 ren1->pair,
1162 NULL,
1163 branch1,
1164 branch2,
1165 ren1->dst_entry,
1166 NULL);
1167 } else {
1168 clean_merge = 0;
1169 conflict_rename_delete(o, ren1->pair, branch1, branch2);
1170 }
1171 } else if ((item = string_list_lookup(renames2Dst, ren1_dst))) {
1172 char *ren2_src, *ren2_dst;
1173 ren2 = item->util;
1174 ren2_src = ren2->pair->one->path;
1175 ren2_dst = ren2->pair->two->path;
1177 clean_merge = 0;
1178 ren2->processed = 1;
1179 remove_file(o, 1, ren2_src,
1180 renamed_stage == 3 || would_lose_untracked(ren1_src));
1182 output(o, 1, "CONFLICT (rename/rename): "
1183 "Rename %s->%s in %s. "
1184 "Rename %s->%s in %s",
1185 ren1_src, ren1_dst, branch1,
1186 ren2_src, ren2_dst, branch2);
1187 conflict_rename_rename_2to1(o, ren1, branch1, ren2, branch2);
1188 } else if ((dst_other.mode == ren1->pair->two->mode) &&
1189 sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
1190 /* Added file on the other side
1191 identical to the file being
1192 renamed: clean merge */
1193 update_file(o, 1, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
1194 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1195 clean_merge = 0;
1196 try_merge = 1;
1197 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
1198 "%s added in %s",
1199 ren1_src, ren1_dst, branch1,
1200 ren1_dst, branch2);
1201 if (o->call_depth) {
1202 struct merge_file_info mfi;
1203 struct diff_filespec one, a, b;
1205 one.path = a.path = b.path =
1206 (char *)ren1_dst;
1207 hashcpy(one.sha1, null_sha1);
1208 one.mode = 0;
1209 hashcpy(a.sha1, ren1->pair->two->sha1);
1210 a.mode = ren1->pair->two->mode;
1211 hashcpy(b.sha1, dst_other.sha1);
1212 b.mode = dst_other.mode;
1213 mfi = merge_file(o, &one, &a, &b,
1214 branch1,
1215 branch2);
1216 output(o, 1, "Adding merged %s", ren1_dst);
1217 update_file(o, 0,
1218 mfi.sha,
1219 mfi.mode,
1220 ren1_dst);
1221 try_merge = 0;
1222 } else {
1223 char *new_path = unique_path(o, ren1_dst, branch2);
1224 output(o, 1, "Adding as %s instead", new_path);
1225 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
1226 free(new_path);
1227 }
1228 } else
1229 try_merge = 1;
1231 if (try_merge) {
1232 struct diff_filespec *one, *a, *b;
1233 src_other.path = (char *)ren1_src;
1235 one = ren1->pair->one;
1236 if (a_renames == renames1) {
1237 a = ren1->pair->two;
1238 b = &src_other;
1239 } else {
1240 b = ren1->pair->two;
1241 a = &src_other;
1242 }
1243 update_entry(ren1->dst_entry, one, a, b);
1244 ren1->dst_entry->involved_in_rename = 1;
1245 if (dir_in_way(ren1_dst, 0 /*check_wc*/)) {
1246 setup_rename_df_conflict_info(RENAME_NORMAL,
1247 ren1->pair,
1248 NULL,
1249 branch1,
1250 NULL,
1251 ren1->dst_entry,
1252 NULL);
1253 }
1254 }
1255 }
1256 }
1257 string_list_clear(&a_by_dst, 0);
1258 string_list_clear(&b_by_dst, 0);
1260 return clean_merge;
1261 }
1263 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1264 {
1265 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1266 }
1268 static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1269 {
1270 void *buf;
1271 enum object_type type;
1272 unsigned long size;
1273 buf = read_sha1_file(sha1, &type, &size);
1274 if (!buf)
1275 return error("cannot read object %s", sha1_to_hex(sha1));
1276 if (type != OBJ_BLOB) {
1277 free(buf);
1278 return error("object %s is not a blob", sha1_to_hex(sha1));
1279 }
1280 strbuf_attach(dst, buf, size, size + 1);
1281 return 0;
1282 }
1284 static int blob_unchanged(const unsigned char *o_sha,
1285 const unsigned char *a_sha,
1286 int renormalize, const char *path)
1287 {
1288 struct strbuf o = STRBUF_INIT;
1289 struct strbuf a = STRBUF_INIT;
1290 int ret = 0; /* assume changed for safety */
1292 if (sha_eq(o_sha, a_sha))
1293 return 1;
1294 if (!renormalize)
1295 return 0;
1297 assert(o_sha && a_sha);
1298 if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1299 goto error_return;
1300 /*
1301 * Note: binary | is used so that both renormalizations are
1302 * performed. Comparison can be skipped if both files are
1303 * unchanged since their sha1s have already been compared.
1304 */
1305 if (renormalize_buffer(path, o.buf, o.len, &o) |
1306 renormalize_buffer(path, a.buf, o.len, &a))
1307 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1309 error_return:
1310 strbuf_release(&o);
1311 strbuf_release(&a);
1312 return ret;
1313 }
1315 static void handle_delete_modify(struct merge_options *o,
1316 const char *path,
1317 const char *new_path,
1318 unsigned char *a_sha, int a_mode,
1319 unsigned char *b_sha, int b_mode)
1320 {
1321 if (!a_sha) {
1322 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1323 "and modified in %s. Version %s of %s left in tree%s%s.",
1324 path, o->branch1,
1325 o->branch2, o->branch2, path,
1326 path == new_path ? "" : " at ",
1327 path == new_path ? "" : new_path);
1328 update_file(o, 0, b_sha, b_mode, new_path);
1329 } else {
1330 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1331 "and modified in %s. Version %s of %s left in tree%s%s.",
1332 path, o->branch2,
1333 o->branch1, o->branch1, path,
1334 path == new_path ? "" : " at ",
1335 path == new_path ? "" : new_path);
1336 update_file(o, 0, a_sha, a_mode, new_path);
1337 }
1338 }
1340 static int merge_content(struct merge_options *o,
1341 unsigned involved_in_rename,
1342 const char *path,
1343 unsigned char *o_sha, int o_mode,
1344 unsigned char *a_sha, int a_mode,
1345 unsigned char *b_sha, int b_mode,
1346 const char *df_rename_conflict_branch)
1347 {
1348 const char *reason = "content";
1349 struct merge_file_info mfi;
1350 struct diff_filespec one, a, b;
1351 unsigned df_conflict_remains = 0;
1353 if (!o_sha) {
1354 reason = "add/add";
1355 o_sha = (unsigned char *)null_sha1;
1356 }
1357 one.path = a.path = b.path = (char *)path;
1358 hashcpy(one.sha1, o_sha);
1359 one.mode = o_mode;
1360 hashcpy(a.sha1, a_sha);
1361 a.mode = a_mode;
1362 hashcpy(b.sha1, b_sha);
1363 b.mode = b_mode;
1365 mfi = merge_file(o, &one, &a, &b, o->branch1, o->branch2);
1366 if (df_rename_conflict_branch &&
1367 dir_in_way(path, !o->call_depth)) {
1368 df_conflict_remains = 1;
1369 }
1371 if (mfi.clean && !df_conflict_remains &&
1372 sha_eq(mfi.sha, a_sha) && mfi.mode == a.mode)
1373 output(o, 3, "Skipped %s (merged same as existing)", path);
1374 else
1375 output(o, 2, "Auto-merging %s", path);
1377 if (!mfi.clean) {
1378 if (S_ISGITLINK(mfi.mode))
1379 reason = "submodule";
1380 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1381 reason, path);
1382 if (involved_in_rename)
1383 update_stages(path, &one, &a, &b);
1384 }
1386 if (df_conflict_remains) {
1387 char *new_path;
1388 update_file_flags(o, mfi.sha, mfi.mode, path,
1389 o->call_depth || mfi.clean, 0);
1390 new_path = unique_path(o, path, df_rename_conflict_branch);
1391 mfi.clean = 0;
1392 output(o, 1, "Adding as %s instead", new_path);
1393 update_file_flags(o, mfi.sha, mfi.mode, new_path, 0, 1);
1394 free(new_path);
1395 } else {
1396 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1397 }
1398 return mfi.clean;
1400 }
1402 /* Per entry merge function */
1403 static int process_entry(struct merge_options *o,
1404 const char *path, struct stage_data *entry)
1405 {
1406 /*
1407 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1408 print_index_entry("\tpath: ", entry);
1409 */
1410 int clean_merge = 1;
1411 int normalize = o->renormalize;
1412 unsigned o_mode = entry->stages[1].mode;
1413 unsigned a_mode = entry->stages[2].mode;
1414 unsigned b_mode = entry->stages[3].mode;
1415 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1416 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1417 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1419 if (entry->rename_df_conflict_info)
1420 return 1; /* Such cases are handled elsewhere. */
1422 entry->processed = 1;
1423 if (o_sha && (!a_sha || !b_sha)) {
1424 /* Case A: Deleted in one */
1425 if ((!a_sha && !b_sha) ||
1426 (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1427 (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1428 /* Deleted in both or deleted in one and
1429 * unchanged in the other */
1430 if (a_sha)
1431 output(o, 2, "Removing %s", path);
1432 /* do not touch working file if it did not exist */
1433 remove_file(o, 1, path, !a_sha);
1434 } else if (dir_in_way(path, 0 /*check_wc*/)) {
1435 entry->processed = 0;
1436 return 1; /* Assume clean until processed */
1437 } else {
1438 /* Deleted in one and changed in the other */
1439 clean_merge = 0;
1440 handle_delete_modify(o, path, path,
1441 a_sha, a_mode, b_sha, b_mode);
1442 }
1444 } else if ((!o_sha && a_sha && !b_sha) ||
1445 (!o_sha && !a_sha && b_sha)) {
1446 /* Case B: Added in one. */
1447 unsigned mode;
1448 const unsigned char *sha;
1450 if (a_sha) {
1451 mode = a_mode;
1452 sha = a_sha;
1453 } else {
1454 mode = b_mode;
1455 sha = b_sha;
1456 }
1457 if (dir_in_way(path, 0 /*check_wc*/)) {
1458 /* Handle D->F conflicts after all subfiles */
1459 entry->processed = 0;
1460 return 1; /* Assume clean until processed */
1461 } else {
1462 output(o, 2, "Adding %s", path);
1463 update_file(o, 1, sha, mode, path);
1464 }
1465 } else if (a_sha && b_sha) {
1466 /* Case C: Added in both (check for same permissions) and */
1467 /* case D: Modified in both, but differently. */
1468 clean_merge = merge_content(o, entry->involved_in_rename, path,
1469 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1470 NULL);
1471 } else if (!o_sha && !a_sha && !b_sha) {
1472 /*
1473 * this entry was deleted altogether. a_mode == 0 means
1474 * we had that path and want to actively remove it.
1475 */
1476 remove_file(o, 1, path, !a_mode);
1477 } else
1478 die("Fatal merge failure, shouldn't happen.");
1480 return clean_merge;
1481 }
1483 /*
1484 * Per entry merge function for D/F (and/or rename) conflicts. In the
1485 * cases we can cleanly resolve D/F conflicts, process_entry() can
1486 * clean out all the files below the directory for us. All D/F
1487 * conflict cases must be handled here at the end to make sure any
1488 * directories that can be cleaned out, are.
1489 *
1490 * Some rename conflicts may also be handled here that don't necessarily
1491 * involve D/F conflicts, since the code to handle them is generic enough
1492 * to handle those rename conflicts with or without D/F conflicts also
1493 * being involved.
1494 */
1495 static int process_df_entry(struct merge_options *o,
1496 const char *path, struct stage_data *entry)
1497 {
1498 int clean_merge = 1;
1499 unsigned o_mode = entry->stages[1].mode;
1500 unsigned a_mode = entry->stages[2].mode;
1501 unsigned b_mode = entry->stages[3].mode;
1502 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1503 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1504 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1506 entry->processed = 1;
1507 if (entry->rename_df_conflict_info) {
1508 struct rename_df_conflict_info *conflict_info = entry->rename_df_conflict_info;
1509 char *src;
1510 switch (conflict_info->rename_type) {
1511 case RENAME_NORMAL:
1512 clean_merge = merge_content(o, entry->involved_in_rename, path,
1513 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1514 conflict_info->branch1);
1515 break;
1516 case RENAME_DELETE:
1517 clean_merge = 0;
1518 conflict_rename_delete(o, conflict_info->pair1,
1519 conflict_info->branch1,
1520 conflict_info->branch2);
1521 break;
1522 case RENAME_ONE_FILE_TO_TWO:
1523 src = conflict_info->pair1->one->path;
1524 clean_merge = 0;
1525 output(o, 1, "CONFLICT (rename/rename): "
1526 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1527 "rename \"%s\"->\"%s\" in \"%s\"%s",
1528 src, conflict_info->pair1->two->path, conflict_info->branch1,
1529 src, conflict_info->pair2->two->path, conflict_info->branch2,
1530 o->call_depth ? " (left unresolved)" : "");
1531 if (o->call_depth) {
1532 remove_file_from_cache(src);
1533 update_file(o, 0, conflict_info->pair1->one->sha1,
1534 conflict_info->pair1->one->mode, src);
1535 }
1536 conflict_rename_rename_1to2(o, conflict_info->pair1,
1537 conflict_info->branch1,
1538 conflict_info->pair2,
1539 conflict_info->branch2);
1540 conflict_info->dst_entry2->processed = 1;
1541 break;
1542 default:
1543 entry->processed = 0;
1544 break;
1545 }
1546 } else if (o_sha && (!a_sha || !b_sha)) {
1547 /* Modify/delete; deleted side may have put a directory in the way */
1548 char *renamed = NULL;
1549 if (dir_in_way(path, !o->call_depth)) {
1550 renamed = unique_path(o, path, a_sha ? o->branch1 : o->branch2);
1551 }
1552 clean_merge = 0;
1553 handle_delete_modify(o, path, renamed ? renamed : path,
1554 a_sha, a_mode, b_sha, b_mode);
1555 free(renamed);
1556 } else if (!o_sha && !!a_sha != !!b_sha) {
1557 /* directory -> (directory, file) or <nothing> -> (directory, file) */
1558 const char *add_branch;
1559 const char *other_branch;
1560 unsigned mode;
1561 const unsigned char *sha;
1562 const char *conf;
1564 if (a_sha) {
1565 add_branch = o->branch1;
1566 other_branch = o->branch2;
1567 mode = a_mode;
1568 sha = a_sha;
1569 conf = "file/directory";
1570 } else {
1571 add_branch = o->branch2;
1572 other_branch = o->branch1;
1573 mode = b_mode;
1574 sha = b_sha;
1575 conf = "directory/file";
1576 }
1577 if (dir_in_way(path, !o->call_depth)) {
1578 char *new_path = unique_path(o, path, add_branch);
1579 clean_merge = 0;
1580 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1581 "Adding %s as %s",
1582 conf, path, other_branch, path, new_path);
1583 update_file(o, 0, sha, mode, new_path);
1584 if (o->call_depth)
1585 remove_file_from_cache(path);
1586 free(new_path);
1587 } else {
1588 output(o, 2, "Adding %s", path);
1589 update_file(o, 1, sha, mode, path);
1590 }
1591 } else {
1592 entry->processed = 0;
1593 return 1; /* not handled; assume clean until processed */
1594 }
1596 return clean_merge;
1597 }
1599 int merge_trees(struct merge_options *o,
1600 struct tree *head,
1601 struct tree *merge,
1602 struct tree *common,
1603 struct tree **result)
1604 {
1605 int code, clean;
1607 if (o->subtree_shift) {
1608 merge = shift_tree_object(head, merge, o->subtree_shift);
1609 common = shift_tree_object(head, common, o->subtree_shift);
1610 }
1612 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1613 output(o, 0, "Already up-to-date!");
1614 *result = head;
1615 return 1;
1616 }
1618 code = git_merge_trees(o->call_depth, common, head, merge);
1620 if (code != 0) {
1621 if (show(o, 4) || o->call_depth)
1622 die("merging of trees %s and %s failed",
1623 sha1_to_hex(head->object.sha1),
1624 sha1_to_hex(merge->object.sha1));
1625 else
1626 exit(128);
1627 }
1629 if (unmerged_cache()) {
1630 struct string_list *entries, *re_head, *re_merge;
1631 int i;
1632 string_list_clear(&o->current_file_set, 1);
1633 string_list_clear(&o->current_directory_set, 1);
1634 get_files_dirs(o, head);
1635 get_files_dirs(o, merge);
1637 entries = get_unmerged();
1638 record_df_conflict_files(o, entries);
1639 re_head = get_renames(o, head, common, head, merge, entries);
1640 re_merge = get_renames(o, merge, common, head, merge, entries);
1641 clean = process_renames(o, re_head, re_merge);
1642 for (i = 0; i < entries->nr; i++) {
1643 const char *path = entries->items[i].string;
1644 struct stage_data *e = entries->items[i].util;
1645 if (!e->processed
1646 && !process_entry(o, path, e))
1647 clean = 0;
1648 }
1649 for (i = 0; i < entries->nr; i++) {
1650 const char *path = entries->items[i].string;
1651 struct stage_data *e = entries->items[i].util;
1652 if (!e->processed
1653 && !process_df_entry(o, path, e))
1654 clean = 0;
1655 }
1656 for (i = 0; i < entries->nr; i++) {
1657 struct stage_data *e = entries->items[i].util;
1658 if (!e->processed)
1659 die("Unprocessed path??? %s",
1660 entries->items[i].string);
1661 }
1663 string_list_clear(re_merge, 0);
1664 string_list_clear(re_head, 0);
1665 string_list_clear(entries, 1);
1667 }
1668 else
1669 clean = 1;
1671 if (o->call_depth)
1672 *result = write_tree_from_memory(o);
1674 return clean;
1675 }
1677 static struct commit_list *reverse_commit_list(struct commit_list *list)
1678 {
1679 struct commit_list *next = NULL, *current, *backup;
1680 for (current = list; current; current = backup) {
1681 backup = current->next;
1682 current->next = next;
1683 next = current;
1684 }
1685 return next;
1686 }
1688 /*
1689 * Merge the commits h1 and h2, return the resulting virtual
1690 * commit object and a flag indicating the cleanness of the merge.
1691 */
1692 int merge_recursive(struct merge_options *o,
1693 struct commit *h1,
1694 struct commit *h2,
1695 struct commit_list *ca,
1696 struct commit **result)
1697 {
1698 struct commit_list *iter;
1699 struct commit *merged_common_ancestors;
1700 struct tree *mrtree = mrtree;
1701 int clean;
1703 if (show(o, 4)) {
1704 output(o, 4, "Merging:");
1705 output_commit_title(o, h1);
1706 output_commit_title(o, h2);
1707 }
1709 if (!ca) {
1710 ca = get_merge_bases(h1, h2, 1);
1711 ca = reverse_commit_list(ca);
1712 }
1714 if (show(o, 5)) {
1715 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1716 for (iter = ca; iter; iter = iter->next)
1717 output_commit_title(o, iter->item);
1718 }
1720 merged_common_ancestors = pop_commit(&ca);
1721 if (merged_common_ancestors == NULL) {
1722 /* if there is no common ancestor, make an empty tree */
1723 struct tree *tree = xcalloc(1, sizeof(struct tree));
1725 tree->object.parsed = 1;
1726 tree->object.type = OBJ_TREE;
1727 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1728 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1729 }
1731 for (iter = ca; iter; iter = iter->next) {
1732 const char *saved_b1, *saved_b2;
1733 o->call_depth++;
1734 /*
1735 * When the merge fails, the result contains files
1736 * with conflict markers. The cleanness flag is
1737 * ignored, it was never actually used, as result of
1738 * merge_trees has always overwritten it: the committed
1739 * "conflicts" were already resolved.
1740 */
1741 discard_cache();
1742 saved_b1 = o->branch1;
1743 saved_b2 = o->branch2;
1744 o->branch1 = "Temporary merge branch 1";
1745 o->branch2 = "Temporary merge branch 2";
1746 merge_recursive(o, merged_common_ancestors, iter->item,
1747 NULL, &merged_common_ancestors);
1748 o->branch1 = saved_b1;
1749 o->branch2 = saved_b2;
1750 o->call_depth--;
1752 if (!merged_common_ancestors)
1753 die("merge returned no commit");
1754 }
1756 discard_cache();
1757 if (!o->call_depth)
1758 read_cache();
1760 o->ancestor = "merged common ancestors";
1761 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1762 &mrtree);
1764 if (o->call_depth) {
1765 *result = make_virtual_commit(mrtree, "merged tree");
1766 commit_list_insert(h1, &(*result)->parents);
1767 commit_list_insert(h2, &(*result)->parents->next);
1768 }
1769 flush_output(o);
1770 if (show(o, 2))
1771 diff_warn_rename_limit("merge.renamelimit",
1772 o->needed_rename_limit, 0);
1773 return clean;
1774 }
1776 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1777 {
1778 struct object *object;
1780 object = deref_tag(parse_object(sha1), name, strlen(name));
1781 if (!object)
1782 return NULL;
1783 if (object->type == OBJ_TREE)
1784 return make_virtual_commit((struct tree*)object, name);
1785 if (object->type != OBJ_COMMIT)
1786 return NULL;
1787 if (parse_commit((struct commit *)object))
1788 return NULL;
1789 return (struct commit *)object;
1790 }
1792 int merge_recursive_generic(struct merge_options *o,
1793 const unsigned char *head,
1794 const unsigned char *merge,
1795 int num_base_list,
1796 const unsigned char **base_list,
1797 struct commit **result)
1798 {
1799 int clean, index_fd;
1800 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1801 struct commit *head_commit = get_ref(head, o->branch1);
1802 struct commit *next_commit = get_ref(merge, o->branch2);
1803 struct commit_list *ca = NULL;
1805 if (base_list) {
1806 int i;
1807 for (i = 0; i < num_base_list; ++i) {
1808 struct commit *base;
1809 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1810 return error("Could not parse object '%s'",
1811 sha1_to_hex(base_list[i]));
1812 commit_list_insert(base, &ca);
1813 }
1814 }
1816 index_fd = hold_locked_index(lock, 1);
1817 clean = merge_recursive(o, head_commit, next_commit, ca,
1818 result);
1819 if (active_cache_changed &&
1820 (write_cache(index_fd, active_cache, active_nr) ||
1821 commit_locked_index(lock)))
1822 return error("Unable to write index.");
1824 return clean ? 0 : 1;
1825 }
1827 static int merge_recursive_config(const char *var, const char *value, void *cb)
1828 {
1829 struct merge_options *o = cb;
1830 if (!strcmp(var, "merge.verbosity")) {
1831 o->verbosity = git_config_int(var, value);
1832 return 0;
1833 }
1834 if (!strcmp(var, "diff.renamelimit")) {
1835 o->diff_rename_limit = git_config_int(var, value);
1836 return 0;
1837 }
1838 if (!strcmp(var, "merge.renamelimit")) {
1839 o->merge_rename_limit = git_config_int(var, value);
1840 return 0;
1841 }
1842 return git_xmerge_config(var, value, cb);
1843 }
1845 void init_merge_options(struct merge_options *o)
1846 {
1847 memset(o, 0, sizeof(struct merge_options));
1848 o->verbosity = 2;
1849 o->buffer_output = 1;
1850 o->diff_rename_limit = -1;
1851 o->merge_rename_limit = -1;
1852 o->renormalize = 0;
1853 git_config(merge_recursive_config, o);
1854 if (getenv("GIT_MERGE_VERBOSITY"))
1855 o->verbosity =
1856 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1857 if (o->verbosity >= 5)
1858 o->buffer_output = 0;
1859 strbuf_init(&o->obuf, 0);
1860 memset(&o->current_file_set, 0, sizeof(struct string_list));
1861 o->current_file_set.strdup_strings = 1;
1862 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1863 o->current_directory_set.strdup_strings = 1;
1864 memset(&o->df_conflict_file_set, 0, sizeof(struct string_list));
1865 o->df_conflict_file_set.strdup_strings = 1;
1866 }
1868 int parse_merge_opt(struct merge_options *o, const char *s)
1869 {
1870 if (!s || !*s)
1871 return -1;
1872 if (!strcmp(s, "ours"))
1873 o->recursive_variant = MERGE_RECURSIVE_OURS;
1874 else if (!strcmp(s, "theirs"))
1875 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
1876 else if (!strcmp(s, "subtree"))
1877 o->subtree_shift = "";
1878 else if (!prefixcmp(s, "subtree="))
1879 o->subtree_shift = s + strlen("subtree=");
1880 else if (!strcmp(s, "patience"))
1881 o->xdl_opts |= XDF_PATIENCE_DIFF;
1882 else if (!strcmp(s, "ignore-space-change"))
1883 o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1884 else if (!strcmp(s, "ignore-all-space"))
1885 o->xdl_opts |= XDF_IGNORE_WHITESPACE;
1886 else if (!strcmp(s, "ignore-space-at-eol"))
1887 o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
1888 else if (!strcmp(s, "renormalize"))
1889 o->renormalize = 1;
1890 else if (!strcmp(s, "no-renormalize"))
1891 o->renormalize = 0;
1892 else if (!prefixcmp(s, "rename-threshold=")) {
1893 const char *score = s + strlen("rename-threshold=");
1894 if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
1895 return -1;
1896 }
1897 else
1898 return -1;
1899 return 0;
1900 }