9c415c8e5a6ff00af2bf8e641d088ea423302f26
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"
24
25static struct tree *shift_tree_object(struct tree *one, struct tree *two,
26 const char *subtree_shift)
27{
28 unsigned char shifted[20];
29
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}
40
41/*
42 * A virtual commit has (const char *)commit->util set to the name.
43 */
44
45static 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}
54
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 */
59static 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}
65
66/*
67 * Since we want to write the index eventually, we cannot reuse the index
68 * for these (temporary) data.
69 */
70struct stage_data
71{
72 struct
73 {
74 unsigned mode;
75 unsigned char sha[20];
76 } stages[4];
77 unsigned processed:1;
78};
79
80static int show(struct merge_options *o, int v)
81{
82 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
83}
84
85static void flush_output(struct merge_options *o)
86{
87 if (o->obuf.len) {
88 fputs(o->obuf.buf, stdout);
89 strbuf_reset(&o->obuf);
90 }
91}
92
93__attribute__((format (printf, 3, 4)))
94static void output(struct merge_options *o, int v, const char *fmt, ...)
95{
96 int len;
97 va_list ap;
98
99 if (!show(o, v))
100 return;
101
102 strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
103 memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
104 strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
105
106 va_start(ap, fmt);
107 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
108 va_end(ap);
109
110 if (len < 0)
111 len = 0;
112 if (len >= strbuf_avail(&o->obuf)) {
113 strbuf_grow(&o->obuf, len + 2);
114 va_start(ap, fmt);
115 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
116 va_end(ap);
117 if (len >= strbuf_avail(&o->obuf)) {
118 die("this should not happen, your snprintf is broken");
119 }
120 }
121 strbuf_setlen(&o->obuf, o->obuf.len + len);
122 strbuf_add(&o->obuf, "\n", 1);
123 if (!o->buffer_output)
124 flush_output(o);
125}
126
127static void output_commit_title(struct merge_options *o, struct commit *commit)
128{
129 int i;
130 flush_output(o);
131 for (i = o->call_depth; i--;)
132 fputs(" ", stdout);
133 if (commit->util)
134 printf("virtual %s\n", (char *)commit->util);
135 else {
136 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
137 if (parse_commit(commit) != 0)
138 printf("(bad commit)\n");
139 else {
140 const char *title;
141 int len = find_commit_subject(commit->buffer, &title);
142 if (len)
143 printf("%.*s\n", len, title);
144 }
145 }
146}
147
148static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
149 const char *path, int stage, int refresh, int options)
150{
151 struct cache_entry *ce;
152 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
153 if (!ce)
154 return error("addinfo_cache failed for path '%s'", path);
155 return add_cache_entry(ce, options);
156}
157
158static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
159{
160 parse_tree(tree);
161 init_tree_desc(desc, tree->buffer, tree->size);
162}
163
164static int git_merge_trees(int index_only,
165 struct tree *common,
166 struct tree *head,
167 struct tree *merge)
168{
169 int rc;
170 struct tree_desc t[3];
171 struct unpack_trees_options opts;
172
173 memset(&opts, 0, sizeof(opts));
174 if (index_only)
175 opts.index_only = 1;
176 else
177 opts.update = 1;
178 opts.merge = 1;
179 opts.head_idx = 2;
180 opts.fn = threeway_merge;
181 opts.src_index = &the_index;
182 opts.dst_index = &the_index;
183 setup_unpack_trees_porcelain(&opts, "merge");
184
185 init_tree_desc_from_tree(t+0, common);
186 init_tree_desc_from_tree(t+1, head);
187 init_tree_desc_from_tree(t+2, merge);
188
189 rc = unpack_trees(3, t, &opts);
190 cache_tree_free(&active_cache_tree);
191 return rc;
192}
193
194struct tree *write_tree_from_memory(struct merge_options *o)
195{
196 struct tree *result = NULL;
197
198 if (unmerged_cache()) {
199 int i;
200 fprintf(stderr, "BUG: There are unmerged index entries:\n");
201 for (i = 0; i < active_nr; i++) {
202 struct cache_entry *ce = active_cache[i];
203 if (ce_stage(ce))
204 fprintf(stderr, "BUG: %d %.*s", ce_stage(ce),
205 (int)ce_namelen(ce), ce->name);
206 }
207 die("Bug in merge-recursive.c");
208 }
209
210 if (!active_cache_tree)
211 active_cache_tree = cache_tree();
212
213 if (!cache_tree_fully_valid(active_cache_tree) &&
214 cache_tree_update(active_cache_tree,
215 active_cache, active_nr, 0, 0) < 0)
216 die("error building trees");
217
218 result = lookup_tree(active_cache_tree->sha1);
219
220 return result;
221}
222
223static int save_files_dirs(const unsigned char *sha1,
224 const char *base, int baselen, const char *path,
225 unsigned int mode, int stage, void *context)
226{
227 int len = strlen(path);
228 char *newpath = xmalloc(baselen + len + 1);
229 struct merge_options *o = context;
230
231 memcpy(newpath, base, baselen);
232 memcpy(newpath + baselen, path, len);
233 newpath[baselen + len] = '\0';
234
235 if (S_ISDIR(mode))
236 string_list_insert(&o->current_directory_set, newpath);
237 else
238 string_list_insert(&o->current_file_set, newpath);
239 free(newpath);
240
241 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
242}
243
244static int get_files_dirs(struct merge_options *o, struct tree *tree)
245{
246 int n;
247 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
248 return 0;
249 n = o->current_file_set.nr + o->current_directory_set.nr;
250 return n;
251}
252
253/*
254 * Returns an index_entry instance which doesn't have to correspond to
255 * a real cache entry in Git's index.
256 */
257static struct stage_data *insert_stage_data(const char *path,
258 struct tree *o, struct tree *a, struct tree *b,
259 struct string_list *entries)
260{
261 struct string_list_item *item;
262 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
263 get_tree_entry(o->object.sha1, path,
264 e->stages[1].sha, &e->stages[1].mode);
265 get_tree_entry(a->object.sha1, path,
266 e->stages[2].sha, &e->stages[2].mode);
267 get_tree_entry(b->object.sha1, path,
268 e->stages[3].sha, &e->stages[3].mode);
269 item = string_list_insert(entries, path);
270 item->util = e;
271 return e;
272}
273
274/*
275 * Create a dictionary mapping file names to stage_data objects. The
276 * dictionary contains one entry for every path with a non-zero stage entry.
277 */
278static struct string_list *get_unmerged(void)
279{
280 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
281 int i;
282
283 unmerged->strdup_strings = 1;
284
285 for (i = 0; i < active_nr; i++) {
286 struct string_list_item *item;
287 struct stage_data *e;
288 struct cache_entry *ce = active_cache[i];
289 if (!ce_stage(ce))
290 continue;
291
292 item = string_list_lookup(unmerged, ce->name);
293 if (!item) {
294 item = string_list_insert(unmerged, ce->name);
295 item->util = xcalloc(1, sizeof(struct stage_data));
296 }
297 e = item->util;
298 e->stages[ce_stage(ce)].mode = ce->ce_mode;
299 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
300 }
301
302 return unmerged;
303}
304
305struct rename
306{
307 struct diff_filepair *pair;
308 struct stage_data *src_entry;
309 struct stage_data *dst_entry;
310 unsigned processed:1;
311};
312
313/*
314 * Get information of all renames which occurred between 'o_tree' and
315 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
316 * 'b_tree') to be able to associate the correct cache entries with
317 * the rename information. 'tree' is always equal to either a_tree or b_tree.
318 */
319static struct string_list *get_renames(struct merge_options *o,
320 struct tree *tree,
321 struct tree *o_tree,
322 struct tree *a_tree,
323 struct tree *b_tree,
324 struct string_list *entries)
325{
326 int i;
327 struct string_list *renames;
328 struct diff_options opts;
329
330 renames = xcalloc(1, sizeof(struct string_list));
331 diff_setup(&opts);
332 DIFF_OPT_SET(&opts, RECURSIVE);
333 opts.detect_rename = DIFF_DETECT_RENAME;
334 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
335 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
336 500;
337 opts.warn_on_too_large_rename = 1;
338 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
339 if (diff_setup_done(&opts) < 0)
340 die("diff setup failed");
341 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
342 diffcore_std(&opts);
343 for (i = 0; i < diff_queued_diff.nr; ++i) {
344 struct string_list_item *item;
345 struct rename *re;
346 struct diff_filepair *pair = diff_queued_diff.queue[i];
347 if (pair->status != 'R') {
348 diff_free_filepair(pair);
349 continue;
350 }
351 re = xmalloc(sizeof(*re));
352 re->processed = 0;
353 re->pair = pair;
354 item = string_list_lookup(entries, re->pair->one->path);
355 if (!item)
356 re->src_entry = insert_stage_data(re->pair->one->path,
357 o_tree, a_tree, b_tree, entries);
358 else
359 re->src_entry = item->util;
360
361 item = string_list_lookup(entries, re->pair->two->path);
362 if (!item)
363 re->dst_entry = insert_stage_data(re->pair->two->path,
364 o_tree, a_tree, b_tree, entries);
365 else
366 re->dst_entry = item->util;
367 item = string_list_insert(renames, pair->one->path);
368 item->util = re;
369 }
370 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
371 diff_queued_diff.nr = 0;
372 diff_flush(&opts);
373 return renames;
374}
375
376static int update_stages(const char *path, struct diff_filespec *o,
377 struct diff_filespec *a, struct diff_filespec *b,
378 int clear)
379{
380 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
381 if (clear)
382 if (remove_file_from_cache(path))
383 return -1;
384 if (o)
385 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
386 return -1;
387 if (a)
388 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
389 return -1;
390 if (b)
391 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
392 return -1;
393 return 0;
394}
395
396static int remove_file(struct merge_options *o, int clean,
397 const char *path, int no_wd)
398{
399 int update_cache = o->call_depth || clean;
400 int update_working_directory = !o->call_depth && !no_wd;
401
402 if (update_cache) {
403 if (remove_file_from_cache(path))
404 return -1;
405 }
406 if (update_working_directory) {
407 if (remove_path(path))
408 return -1;
409 }
410 return 0;
411}
412
413static char *unique_path(struct merge_options *o, const char *path, const char *branch)
414{
415 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
416 int suffix = 0;
417 struct stat st;
418 char *p = newpath + strlen(path);
419 strcpy(newpath, path);
420 *(p++) = '~';
421 strcpy(p, branch);
422 for (; *p; ++p)
423 if ('/' == *p)
424 *p = '_';
425 while (string_list_has_string(&o->current_file_set, newpath) ||
426 string_list_has_string(&o->current_directory_set, newpath) ||
427 lstat(newpath, &st) == 0)
428 sprintf(p, "_%d", suffix++);
429
430 string_list_insert(&o->current_file_set, newpath);
431 return newpath;
432}
433
434static void flush_buffer(int fd, const char *buf, unsigned long size)
435{
436 while (size > 0) {
437 long ret = write_in_full(fd, buf, size);
438 if (ret < 0) {
439 /* Ignore epipe */
440 if (errno == EPIPE)
441 break;
442 die_errno("merge-recursive");
443 } else if (!ret) {
444 die("merge-recursive: disk full?");
445 }
446 size -= ret;
447 buf += ret;
448 }
449}
450
451static int would_lose_untracked(const char *path)
452{
453 int pos = cache_name_pos(path, strlen(path));
454
455 if (pos < 0)
456 pos = -1 - pos;
457 while (pos < active_nr &&
458 !strcmp(path, active_cache[pos]->name)) {
459 /*
460 * If stage #0, it is definitely tracked.
461 * If it has stage #2 then it was tracked
462 * before this merge started. All other
463 * cases the path was not tracked.
464 */
465 switch (ce_stage(active_cache[pos])) {
466 case 0:
467 case 2:
468 return 0;
469 }
470 pos++;
471 }
472 return file_exists(path);
473}
474
475static int make_room_for_path(const char *path)
476{
477 int status;
478 const char *msg = "failed to create path '%s'%s";
479
480 status = safe_create_leading_directories_const(path);
481 if (status) {
482 if (status == -3) {
483 /* something else exists */
484 error(msg, path, ": perhaps a D/F conflict?");
485 return -1;
486 }
487 die(msg, path, "");
488 }
489
490 /*
491 * Do not unlink a file in the work tree if we are not
492 * tracking it.
493 */
494 if (would_lose_untracked(path))
495 return error("refusing to lose untracked file at '%s'",
496 path);
497
498 /* Successful unlink is good.. */
499 if (!unlink(path))
500 return 0;
501 /* .. and so is no existing file */
502 if (errno == ENOENT)
503 return 0;
504 /* .. but not some other error (who really cares what?) */
505 return error(msg, path, ": perhaps a D/F conflict?");
506}
507
508static void update_file_flags(struct merge_options *o,
509 const unsigned char *sha,
510 unsigned mode,
511 const char *path,
512 int update_cache,
513 int update_wd)
514{
515 if (o->call_depth)
516 update_wd = 0;
517
518 if (update_wd) {
519 enum object_type type;
520 void *buf;
521 unsigned long size;
522
523 if (S_ISGITLINK(mode)) {
524 /*
525 * We may later decide to recursively descend into
526 * the submodule directory and update its index
527 * and/or work tree, but we do not do that now.
528 */
529 update_wd = 0;
530 goto update_index;
531 }
532
533 buf = read_sha1_file(sha, &type, &size);
534 if (!buf)
535 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
536 if (type != OBJ_BLOB)
537 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
538 if (S_ISREG(mode)) {
539 struct strbuf strbuf = STRBUF_INIT;
540 if (convert_to_working_tree(path, buf, size, &strbuf)) {
541 free(buf);
542 size = strbuf.len;
543 buf = strbuf_detach(&strbuf, NULL);
544 }
545 }
546
547 if (make_room_for_path(path) < 0) {
548 update_wd = 0;
549 free(buf);
550 goto update_index;
551 }
552 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
553 int fd;
554 if (mode & 0100)
555 mode = 0777;
556 else
557 mode = 0666;
558 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
559 if (fd < 0)
560 die_errno("failed to open '%s'", path);
561 flush_buffer(fd, buf, size);
562 close(fd);
563 } else if (S_ISLNK(mode)) {
564 char *lnk = xmemdupz(buf, size);
565 safe_create_leading_directories_const(path);
566 unlink(path);
567 if (symlink(lnk, path))
568 die_errno("failed to symlink '%s'", path);
569 free(lnk);
570 } else
571 die("do not know what to do with %06o %s '%s'",
572 mode, sha1_to_hex(sha), path);
573 free(buf);
574 }
575 update_index:
576 if (update_cache)
577 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
578}
579
580static void update_file(struct merge_options *o,
581 int clean,
582 const unsigned char *sha,
583 unsigned mode,
584 const char *path)
585{
586 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
587}
588
589/* Low level file merging, update and removal */
590
591struct merge_file_info
592{
593 unsigned char sha[20];
594 unsigned mode;
595 unsigned clean:1,
596 merge:1;
597};
598
599static int merge_3way(struct merge_options *o,
600 mmbuffer_t *result_buf,
601 struct diff_filespec *one,
602 struct diff_filespec *a,
603 struct diff_filespec *b,
604 const char *branch1,
605 const char *branch2)
606{
607 mmfile_t orig, src1, src2;
608 char *base_name, *name1, *name2;
609 int merge_status;
610 int favor;
611
612 if (o->call_depth)
613 favor = 0;
614 else {
615 switch (o->recursive_variant) {
616 case MERGE_RECURSIVE_OURS:
617 favor = XDL_MERGE_FAVOR_OURS;
618 break;
619 case MERGE_RECURSIVE_THEIRS:
620 favor = XDL_MERGE_FAVOR_THEIRS;
621 break;
622 default:
623 favor = 0;
624 break;
625 }
626 }
627
628 if (strcmp(a->path, b->path) ||
629 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
630 base_name = o->ancestor == NULL ? NULL :
631 xstrdup(mkpath("%s:%s", o->ancestor, one->path));
632 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
633 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
634 } else {
635 base_name = o->ancestor == NULL ? NULL :
636 xstrdup(mkpath("%s", o->ancestor));
637 name1 = xstrdup(mkpath("%s", branch1));
638 name2 = xstrdup(mkpath("%s", branch2));
639 }
640
641 read_mmblob(&orig, one->sha1);
642 read_mmblob(&src1, a->sha1);
643 read_mmblob(&src2, b->sha1);
644
645 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
646 &src1, name1, &src2, name2,
647 ((o->call_depth ? LL_OPT_VIRTUAL_ANCESTOR : 0) |
648 (o->renormalize ? LL_OPT_RENORMALIZE : 0) |
649 create_ll_flag(favor)));
650
651 free(name1);
652 free(name2);
653 free(orig.ptr);
654 free(src1.ptr);
655 free(src2.ptr);
656 return merge_status;
657}
658
659static struct merge_file_info merge_file(struct merge_options *o,
660 struct diff_filespec *one,
661 struct diff_filespec *a,
662 struct diff_filespec *b,
663 const char *branch1,
664 const char *branch2)
665{
666 struct merge_file_info result;
667 result.merge = 0;
668 result.clean = 1;
669
670 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
671 result.clean = 0;
672 if (S_ISREG(a->mode)) {
673 result.mode = a->mode;
674 hashcpy(result.sha, a->sha1);
675 } else {
676 result.mode = b->mode;
677 hashcpy(result.sha, b->sha1);
678 }
679 } else {
680 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
681 result.merge = 1;
682
683 /*
684 * Merge modes
685 */
686 if (a->mode == b->mode || a->mode == one->mode)
687 result.mode = b->mode;
688 else {
689 result.mode = a->mode;
690 if (b->mode != one->mode) {
691 result.clean = 0;
692 result.merge = 1;
693 }
694 }
695
696 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
697 hashcpy(result.sha, b->sha1);
698 else if (sha_eq(b->sha1, one->sha1))
699 hashcpy(result.sha, a->sha1);
700 else if (S_ISREG(a->mode)) {
701 mmbuffer_t result_buf;
702 int merge_status;
703
704 merge_status = merge_3way(o, &result_buf, one, a, b,
705 branch1, branch2);
706
707 if ((merge_status < 0) || !result_buf.ptr)
708 die("Failed to execute internal merge");
709
710 if (write_sha1_file(result_buf.ptr, result_buf.size,
711 blob_type, result.sha))
712 die("Unable to add %s to database",
713 a->path);
714
715 free(result_buf.ptr);
716 result.clean = (merge_status == 0);
717 } else if (S_ISGITLINK(a->mode)) {
718 result.clean = merge_submodule(result.sha, one->path, one->sha1,
719 a->sha1, b->sha1);
720 } else if (S_ISLNK(a->mode)) {
721 hashcpy(result.sha, a->sha1);
722
723 if (!sha_eq(a->sha1, b->sha1))
724 result.clean = 0;
725 } else {
726 die("unsupported object type in the tree");
727 }
728 }
729
730 return result;
731}
732
733static void conflict_rename_delete(struct merge_options *o,
734 struct diff_filepair *pair,
735 const char *rename_branch,
736 const char *other_branch)
737{
738 char *dest_name = pair->two->path;
739
740 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
741 "and deleted in %s",
742 pair->one->path, pair->two->path, rename_branch,
743 other_branch);
744 if (!o->call_depth)
745 update_stages(dest_name, NULL,
746 rename_branch == o->branch1 ? pair->two : NULL,
747 rename_branch == o->branch1 ? NULL : pair->two,
748 1);
749 update_file(o, 0, pair->two->sha1, pair->two->mode, dest_name);
750}
751
752static void conflict_rename_rename_1to2(struct merge_options *o,
753 struct rename *ren1,
754 const char *branch1,
755 struct rename *ren2,
756 const char *branch2)
757{
758 /* One file was renamed in both branches, but to different names. */
759 char *del[2];
760 int delp = 0;
761 const char *ren1_dst = ren1->pair->two->path;
762 const char *ren2_dst = ren2->pair->two->path;
763 const char *dst_name1 = ren1_dst;
764 const char *dst_name2 = ren2_dst;
765 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
766 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
767 output(o, 1, "%s is a directory in %s adding as %s instead",
768 ren1_dst, branch2, dst_name1);
769 remove_file(o, 0, ren1_dst, 0);
770 }
771 if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
772 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
773 output(o, 1, "%s is a directory in %s adding as %s instead",
774 ren2_dst, branch1, dst_name2);
775 remove_file(o, 0, ren2_dst, 0);
776 }
777 if (o->call_depth) {
778 remove_file_from_cache(dst_name1);
779 remove_file_from_cache(dst_name2);
780 /*
781 * Uncomment to leave the conflicting names in the resulting tree
782 *
783 * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
784 * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
785 */
786 } else {
787 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
788 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
789 }
790 while (delp--)
791 free(del[delp]);
792}
793
794static void conflict_rename_rename_2to1(struct merge_options *o,
795 struct rename *ren1,
796 const char *branch1,
797 struct rename *ren2,
798 const char *branch2)
799{
800 /* Two files were renamed to the same thing. */
801 char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
802 char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
803 output(o, 1, "Renaming %s to %s and %s to %s instead",
804 ren1->pair->one->path, new_path1,
805 ren2->pair->one->path, new_path2);
806 remove_file(o, 0, ren1->pair->two->path, 0);
807 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
808 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
809 free(new_path2);
810 free(new_path1);
811}
812
813static int process_renames(struct merge_options *o,
814 struct string_list *a_renames,
815 struct string_list *b_renames)
816{
817 int clean_merge = 1, i, j;
818 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
819 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
820 const struct rename *sre;
821
822 for (i = 0; i < a_renames->nr; i++) {
823 sre = a_renames->items[i].util;
824 string_list_insert(&a_by_dst, sre->pair->two->path)->util
825 = sre->dst_entry;
826 }
827 for (i = 0; i < b_renames->nr; i++) {
828 sre = b_renames->items[i].util;
829 string_list_insert(&b_by_dst, sre->pair->two->path)->util
830 = sre->dst_entry;
831 }
832
833 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
834 char *src;
835 struct string_list *renames1, *renames2Dst;
836 struct rename *ren1 = NULL, *ren2 = NULL;
837 const char *branch1, *branch2;
838 const char *ren1_src, *ren1_dst;
839
840 if (i >= a_renames->nr) {
841 ren2 = b_renames->items[j++].util;
842 } else if (j >= b_renames->nr) {
843 ren1 = a_renames->items[i++].util;
844 } else {
845 int compare = strcmp(a_renames->items[i].string,
846 b_renames->items[j].string);
847 if (compare <= 0)
848 ren1 = a_renames->items[i++].util;
849 if (compare >= 0)
850 ren2 = b_renames->items[j++].util;
851 }
852
853 /* TODO: refactor, so that 1/2 are not needed */
854 if (ren1) {
855 renames1 = a_renames;
856 renames2Dst = &b_by_dst;
857 branch1 = o->branch1;
858 branch2 = o->branch2;
859 } else {
860 struct rename *tmp;
861 renames1 = b_renames;
862 renames2Dst = &a_by_dst;
863 branch1 = o->branch2;
864 branch2 = o->branch1;
865 tmp = ren2;
866 ren2 = ren1;
867 ren1 = tmp;
868 }
869 src = ren1->pair->one->path;
870
871 ren1->dst_entry->processed = 1;
872 ren1->src_entry->processed = 1;
873
874 if (ren1->processed)
875 continue;
876 ren1->processed = 1;
877
878 ren1_src = ren1->pair->one->path;
879 ren1_dst = ren1->pair->two->path;
880
881 if (ren2) {
882 const char *ren2_src = ren2->pair->one->path;
883 const char *ren2_dst = ren2->pair->two->path;
884 /* Renamed in 1 and renamed in 2 */
885 if (strcmp(ren1_src, ren2_src) != 0)
886 die("ren1.src != ren2.src");
887 ren2->dst_entry->processed = 1;
888 ren2->processed = 1;
889 if (strcmp(ren1_dst, ren2_dst) != 0) {
890 clean_merge = 0;
891 output(o, 1, "CONFLICT (rename/rename): "
892 "Rename \"%s\"->\"%s\" in branch \"%s\" "
893 "rename \"%s\"->\"%s\" in \"%s\"%s",
894 src, ren1_dst, branch1,
895 src, ren2_dst, branch2,
896 o->call_depth ? " (left unresolved)": "");
897 if (o->call_depth) {
898 remove_file_from_cache(src);
899 update_file(o, 0, ren1->pair->one->sha1,
900 ren1->pair->one->mode, src);
901 }
902 conflict_rename_rename_1to2(o, ren1, branch1, ren2, branch2);
903 } else {
904 struct merge_file_info mfi;
905 remove_file(o, 1, ren1_src, 1);
906 mfi = merge_file(o,
907 ren1->pair->one,
908 ren1->pair->two,
909 ren2->pair->two,
910 branch1,
911 branch2);
912 if (mfi.merge || !mfi.clean)
913 output(o, 1, "Renaming %s->%s", src, ren1_dst);
914
915 if (mfi.merge)
916 output(o, 2, "Auto-merging %s", ren1_dst);
917
918 if (!mfi.clean) {
919 output(o, 1, "CONFLICT (content): merge conflict in %s",
920 ren1_dst);
921 clean_merge = 0;
922
923 if (!o->call_depth)
924 update_stages(ren1_dst,
925 ren1->pair->one,
926 ren1->pair->two,
927 ren2->pair->two,
928 1 /* clear */);
929 }
930 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
931 }
932 } else {
933 /* Renamed in 1, maybe changed in 2 */
934 struct string_list_item *item;
935 /* we only use sha1 and mode of these */
936 struct diff_filespec src_other, dst_other;
937 int try_merge;
938
939 /*
940 * unpack_trees loads entries from common-commit
941 * into stage 1, from head-commit into stage 2, and
942 * from merge-commit into stage 3. We keep track
943 * of which side corresponds to the rename.
944 */
945 int renamed_stage = a_renames == renames1 ? 2 : 3;
946 int other_stage = a_renames == renames1 ? 3 : 2;
947
948 remove_file(o, 1, ren1_src, o->call_depth || renamed_stage == 2);
949
950 hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
951 src_other.mode = ren1->src_entry->stages[other_stage].mode;
952 hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
953 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
954 try_merge = 0;
955
956 if (sha_eq(src_other.sha1, null_sha1)) {
957 clean_merge = 0;
958 conflict_rename_delete(o, ren1->pair, branch1, branch2);
959 } else if ((dst_other.mode == ren1->pair->two->mode) &&
960 sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
961 /* Added file on the other side
962 identical to the file being
963 renamed: clean merge */
964 update_file(o, 1, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
965 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
966 const char *new_path;
967 clean_merge = 0;
968 try_merge = 1;
969 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
970 "%s added in %s",
971 ren1_src, ren1_dst, branch1,
972 ren1_dst, branch2);
973 if (o->call_depth) {
974 struct merge_file_info mfi;
975 struct diff_filespec one, a, b;
976
977 one.path = a.path = b.path =
978 (char *)ren1_dst;
979 hashcpy(one.sha1, null_sha1);
980 one.mode = 0;
981 hashcpy(a.sha1, ren1->pair->two->sha1);
982 a.mode = ren1->pair->two->mode;
983 hashcpy(b.sha1, dst_other.sha1);
984 b.mode = dst_other.mode;
985 mfi = merge_file(o, &one, &a, &b,
986 branch1,
987 branch2);
988 output(o, 1, "Adding merged %s", ren1_dst);
989 update_file(o, 0,
990 mfi.sha,
991 mfi.mode,
992 ren1_dst);
993 } else {
994 new_path = unique_path(o, ren1_dst, branch2);
995 output(o, 1, "Adding as %s instead", new_path);
996 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
997 }
998 } else if ((item = string_list_lookup(renames2Dst, ren1_dst))) {
999 ren2 = item->util;
1000 clean_merge = 0;
1001 ren2->processed = 1;
1002 output(o, 1, "CONFLICT (rename/rename): "
1003 "Rename %s->%s in %s. "
1004 "Rename %s->%s in %s",
1005 ren1_src, ren1_dst, branch1,
1006 ren2->pair->one->path, ren2->pair->two->path, branch2);
1007 conflict_rename_rename_2to1(o, ren1, branch1, ren2, branch2);
1008 } else
1009 try_merge = 1;
1010
1011 if (try_merge) {
1012 struct diff_filespec *one, *a, *b;
1013 struct merge_file_info mfi;
1014 src_other.path = (char *)ren1_src;
1015
1016 one = ren1->pair->one;
1017 if (a_renames == renames1) {
1018 a = ren1->pair->two;
1019 b = &src_other;
1020 } else {
1021 b = ren1->pair->two;
1022 a = &src_other;
1023 }
1024 mfi = merge_file(o, one, a, b,
1025 o->branch1, o->branch2);
1026
1027 if (mfi.clean &&
1028 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
1029 mfi.mode == ren1->pair->two->mode) {
1030 /*
1031 * This message is part of
1032 * t6022 test. If you change
1033 * it update the test too.
1034 */
1035 output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
1036
1037 /* There may be higher stage entries left
1038 * in the index (e.g. due to a D/F
1039 * conflict) that need to be resolved.
1040 */
1041 if (!ren1->dst_entry->stages[2].mode !=
1042 !ren1->dst_entry->stages[3].mode)
1043 ren1->dst_entry->processed = 0;
1044 } else {
1045 if (mfi.merge || !mfi.clean)
1046 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
1047 if (mfi.merge)
1048 output(o, 2, "Auto-merging %s", ren1_dst);
1049 if (!mfi.clean) {
1050 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
1051 ren1_dst);
1052 clean_merge = 0;
1053
1054 if (!o->call_depth)
1055 update_stages(ren1_dst,
1056 one, a, b, 1);
1057 }
1058 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1059 }
1060 }
1061 }
1062 }
1063 string_list_clear(&a_by_dst, 0);
1064 string_list_clear(&b_by_dst, 0);
1065
1066 return clean_merge;
1067}
1068
1069static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1070{
1071 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1072}
1073
1074static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1075{
1076 void *buf;
1077 enum object_type type;
1078 unsigned long size;
1079 buf = read_sha1_file(sha1, &type, &size);
1080 if (!buf)
1081 return error("cannot read object %s", sha1_to_hex(sha1));
1082 if (type != OBJ_BLOB) {
1083 free(buf);
1084 return error("object %s is not a blob", sha1_to_hex(sha1));
1085 }
1086 strbuf_attach(dst, buf, size, size + 1);
1087 return 0;
1088}
1089
1090static int blob_unchanged(const unsigned char *o_sha,
1091 const unsigned char *a_sha,
1092 int renormalize, const char *path)
1093{
1094 struct strbuf o = STRBUF_INIT;
1095 struct strbuf a = STRBUF_INIT;
1096 int ret = 0; /* assume changed for safety */
1097
1098 if (sha_eq(o_sha, a_sha))
1099 return 1;
1100 if (!renormalize)
1101 return 0;
1102
1103 assert(o_sha && a_sha);
1104 if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1105 goto error_return;
1106 /*
1107 * Note: binary | is used so that both renormalizations are
1108 * performed. Comparison can be skipped if both files are
1109 * unchanged since their sha1s have already been compared.
1110 */
1111 if (renormalize_buffer(path, o.buf, o.len, &o) |
1112 renormalize_buffer(path, a.buf, o.len, &a))
1113 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1114
1115error_return:
1116 strbuf_release(&o);
1117 strbuf_release(&a);
1118 return ret;
1119}
1120
1121static void handle_delete_modify(struct merge_options *o,
1122 const char *path,
1123 unsigned char *a_sha, int a_mode,
1124 unsigned char *b_sha, int b_mode)
1125{
1126 if (!a_sha) {
1127 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1128 "and modified in %s. Version %s of %s left in tree.",
1129 path, o->branch1,
1130 o->branch2, o->branch2, path);
1131 update_file(o, 0, b_sha, b_mode, path);
1132 } else {
1133 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1134 "and modified in %s. Version %s of %s left in tree.",
1135 path, o->branch2,
1136 o->branch1, o->branch1, path);
1137 update_file(o, 0, a_sha, a_mode, path);
1138 }
1139}
1140
1141
1142static int merge_content(struct merge_options *o,
1143 const char *path,
1144 unsigned char *o_sha, int o_mode,
1145 unsigned char *a_sha, int a_mode,
1146 unsigned char *b_sha, int b_mode)
1147{
1148 const char *reason = "content";
1149 struct merge_file_info mfi;
1150 struct diff_filespec one, a, b;
1151
1152 if (!o_sha) {
1153 reason = "add/add";
1154 o_sha = (unsigned char *)null_sha1;
1155 }
1156 one.path = a.path = b.path = (char *)path;
1157 hashcpy(one.sha1, o_sha);
1158 one.mode = o_mode;
1159 hashcpy(a.sha1, a_sha);
1160 a.mode = a_mode;
1161 hashcpy(b.sha1, b_sha);
1162 b.mode = b_mode;
1163
1164 mfi = merge_file(o, &one, &a, &b, o->branch1, o->branch2);
1165 if (mfi.clean && sha_eq(mfi.sha, a_sha) && mfi.mode == a.mode)
1166 output(o, 3, "Skipped %s (merged same as existing)", path);
1167 else
1168 output(o, 2, "Auto-merging %s", path);
1169
1170 if (!mfi.clean) {
1171 if (S_ISGITLINK(mfi.mode))
1172 reason = "submodule";
1173 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1174 reason, path);
1175 }
1176
1177 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1178 return mfi.clean;
1179
1180}
1181
1182/* Per entry merge function */
1183static int process_entry(struct merge_options *o,
1184 const char *path, struct stage_data *entry)
1185{
1186 /*
1187 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1188 print_index_entry("\tpath: ", entry);
1189 */
1190 int clean_merge = 1;
1191 int normalize = o->renormalize;
1192 unsigned o_mode = entry->stages[1].mode;
1193 unsigned a_mode = entry->stages[2].mode;
1194 unsigned b_mode = entry->stages[3].mode;
1195 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1196 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1197 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1198
1199 entry->processed = 1;
1200 if (o_sha && (!a_sha || !b_sha)) {
1201 /* Case A: Deleted in one */
1202 if ((!a_sha && !b_sha) ||
1203 (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1204 (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1205 /* Deleted in both or deleted in one and
1206 * unchanged in the other */
1207 if (a_sha)
1208 output(o, 2, "Removing %s", path);
1209 /* do not touch working file if it did not exist */
1210 remove_file(o, 1, path, !a_sha);
1211 } else {
1212 /* Deleted in one and changed in the other */
1213 clean_merge = 0;
1214 handle_delete_modify(o, path,
1215 a_sha, a_mode, b_sha, b_mode);
1216 }
1217
1218 } else if ((!o_sha && a_sha && !b_sha) ||
1219 (!o_sha && !a_sha && b_sha)) {
1220 /* Case B: Added in one. */
1221 unsigned mode;
1222 const unsigned char *sha;
1223
1224 if (a_sha) {
1225 mode = a_mode;
1226 sha = a_sha;
1227 } else {
1228 mode = b_mode;
1229 sha = b_sha;
1230 }
1231 if (string_list_has_string(&o->current_directory_set, path)) {
1232 /* Handle D->F conflicts after all subfiles */
1233 entry->processed = 0;
1234 /* But get any file out of the way now, so conflicted
1235 * entries below the directory of the same name can
1236 * be put in the working directory.
1237 */
1238 if (a_sha)
1239 output(o, 2, "Removing %s", path);
1240 /* do not touch working file if it did not exist */
1241 remove_file(o, 0, path, !a_sha);
1242 return 1; /* Assume clean till processed */
1243 } else {
1244 output(o, 2, "Adding %s", path);
1245 update_file(o, 1, sha, mode, path);
1246 }
1247 } else if (a_sha && b_sha) {
1248 /* Case C: Added in both (check for same permissions) and */
1249 /* case D: Modified in both, but differently. */
1250 clean_merge = merge_content(o, path,
1251 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode);
1252 } else if (!o_sha && !a_sha && !b_sha) {
1253 /*
1254 * this entry was deleted altogether. a_mode == 0 means
1255 * we had that path and want to actively remove it.
1256 */
1257 remove_file(o, 1, path, !a_mode);
1258 } else
1259 die("Fatal merge failure, shouldn't happen.");
1260
1261 return clean_merge;
1262}
1263
1264/*
1265 * Per entry merge function for D/F conflicts, to be called only after
1266 * all files below dir have been processed. We do this because in the
1267 * cases we can cleanly resolve D/F conflicts, process_entry() can clean
1268 * out all the files below the directory for us.
1269 */
1270static int process_df_entry(struct merge_options *o,
1271 const char *path, struct stage_data *entry)
1272{
1273 int clean_merge = 1;
1274 unsigned o_mode = entry->stages[1].mode;
1275 unsigned a_mode = entry->stages[2].mode;
1276 unsigned b_mode = entry->stages[3].mode;
1277 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1278 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1279 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1280 const char *add_branch;
1281 const char *other_branch;
1282 unsigned mode;
1283 const unsigned char *sha;
1284 const char *conf;
1285 struct stat st;
1286
1287 if (!((!o_sha && a_sha && !b_sha) || (!o_sha && !a_sha && b_sha)))
1288 return 1; /* we don't handle non D-F cases */
1289
1290 entry->processed = 1;
1291
1292 if (a_sha) {
1293 add_branch = o->branch1;
1294 other_branch = o->branch2;
1295 mode = a_mode;
1296 sha = a_sha;
1297 conf = "file/directory";
1298 } else {
1299 add_branch = o->branch2;
1300 other_branch = o->branch1;
1301 mode = b_mode;
1302 sha = b_sha;
1303 conf = "directory/file";
1304 }
1305 if (lstat(path, &st) == 0 && S_ISDIR(st.st_mode)) {
1306 const char *new_path = unique_path(o, path, add_branch);
1307 clean_merge = 0;
1308 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1309 "Adding %s as %s",
1310 conf, path, other_branch, path, new_path);
1311 remove_file(o, 0, path, 0);
1312 update_file(o, 0, sha, mode, new_path);
1313 } else {
1314 output(o, 2, "Adding %s", path);
1315 update_file(o, 1, sha, mode, path);
1316 }
1317
1318 return clean_merge;
1319}
1320
1321int merge_trees(struct merge_options *o,
1322 struct tree *head,
1323 struct tree *merge,
1324 struct tree *common,
1325 struct tree **result)
1326{
1327 int code, clean;
1328
1329 if (o->subtree_shift) {
1330 merge = shift_tree_object(head, merge, o->subtree_shift);
1331 common = shift_tree_object(head, common, o->subtree_shift);
1332 }
1333
1334 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1335 output(o, 0, "Already up-to-date!");
1336 *result = head;
1337 return 1;
1338 }
1339
1340 code = git_merge_trees(o->call_depth, common, head, merge);
1341
1342 if (code != 0) {
1343 if (show(o, 4) || o->call_depth)
1344 die("merging of trees %s and %s failed",
1345 sha1_to_hex(head->object.sha1),
1346 sha1_to_hex(merge->object.sha1));
1347 else
1348 exit(128);
1349 }
1350
1351 if (unmerged_cache()) {
1352 struct string_list *entries, *re_head, *re_merge;
1353 int i;
1354 string_list_clear(&o->current_file_set, 1);
1355 string_list_clear(&o->current_directory_set, 1);
1356 get_files_dirs(o, head);
1357 get_files_dirs(o, merge);
1358
1359 entries = get_unmerged();
1360 re_head = get_renames(o, head, common, head, merge, entries);
1361 re_merge = get_renames(o, merge, common, head, merge, entries);
1362 clean = process_renames(o, re_head, re_merge);
1363 for (i = 0; i < entries->nr; i++) {
1364 const char *path = entries->items[i].string;
1365 struct stage_data *e = entries->items[i].util;
1366 if (!e->processed
1367 && !process_entry(o, path, e))
1368 clean = 0;
1369 }
1370 for (i = 0; i < entries->nr; i++) {
1371 const char *path = entries->items[i].string;
1372 struct stage_data *e = entries->items[i].util;
1373 if (!e->processed
1374 && !process_df_entry(o, path, e))
1375 clean = 0;
1376 }
1377 for (i = 0; i < entries->nr; i++) {
1378 struct stage_data *e = entries->items[i].util;
1379 if (!e->processed)
1380 die("Unprocessed path??? %s",
1381 entries->items[i].string);
1382 }
1383
1384 string_list_clear(re_merge, 0);
1385 string_list_clear(re_head, 0);
1386 string_list_clear(entries, 1);
1387
1388 }
1389 else
1390 clean = 1;
1391
1392 if (o->call_depth)
1393 *result = write_tree_from_memory(o);
1394
1395 return clean;
1396}
1397
1398static struct commit_list *reverse_commit_list(struct commit_list *list)
1399{
1400 struct commit_list *next = NULL, *current, *backup;
1401 for (current = list; current; current = backup) {
1402 backup = current->next;
1403 current->next = next;
1404 next = current;
1405 }
1406 return next;
1407}
1408
1409/*
1410 * Merge the commits h1 and h2, return the resulting virtual
1411 * commit object and a flag indicating the cleanness of the merge.
1412 */
1413int merge_recursive(struct merge_options *o,
1414 struct commit *h1,
1415 struct commit *h2,
1416 struct commit_list *ca,
1417 struct commit **result)
1418{
1419 struct commit_list *iter;
1420 struct commit *merged_common_ancestors;
1421 struct tree *mrtree = mrtree;
1422 int clean;
1423
1424 if (show(o, 4)) {
1425 output(o, 4, "Merging:");
1426 output_commit_title(o, h1);
1427 output_commit_title(o, h2);
1428 }
1429
1430 if (!ca) {
1431 ca = get_merge_bases(h1, h2, 1);
1432 ca = reverse_commit_list(ca);
1433 }
1434
1435 if (show(o, 5)) {
1436 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1437 for (iter = ca; iter; iter = iter->next)
1438 output_commit_title(o, iter->item);
1439 }
1440
1441 merged_common_ancestors = pop_commit(&ca);
1442 if (merged_common_ancestors == NULL) {
1443 /* if there is no common ancestor, make an empty tree */
1444 struct tree *tree = xcalloc(1, sizeof(struct tree));
1445
1446 tree->object.parsed = 1;
1447 tree->object.type = OBJ_TREE;
1448 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1449 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1450 }
1451
1452 for (iter = ca; iter; iter = iter->next) {
1453 const char *saved_b1, *saved_b2;
1454 o->call_depth++;
1455 /*
1456 * When the merge fails, the result contains files
1457 * with conflict markers. The cleanness flag is
1458 * ignored, it was never actually used, as result of
1459 * merge_trees has always overwritten it: the committed
1460 * "conflicts" were already resolved.
1461 */
1462 discard_cache();
1463 saved_b1 = o->branch1;
1464 saved_b2 = o->branch2;
1465 o->branch1 = "Temporary merge branch 1";
1466 o->branch2 = "Temporary merge branch 2";
1467 merge_recursive(o, merged_common_ancestors, iter->item,
1468 NULL, &merged_common_ancestors);
1469 o->branch1 = saved_b1;
1470 o->branch2 = saved_b2;
1471 o->call_depth--;
1472
1473 if (!merged_common_ancestors)
1474 die("merge returned no commit");
1475 }
1476
1477 discard_cache();
1478 if (!o->call_depth)
1479 read_cache();
1480
1481 o->ancestor = "merged common ancestors";
1482 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1483 &mrtree);
1484
1485 if (o->call_depth) {
1486 *result = make_virtual_commit(mrtree, "merged tree");
1487 commit_list_insert(h1, &(*result)->parents);
1488 commit_list_insert(h2, &(*result)->parents->next);
1489 }
1490 flush_output(o);
1491 return clean;
1492}
1493
1494static struct commit *get_ref(const unsigned char *sha1, const char *name)
1495{
1496 struct object *object;
1497
1498 object = deref_tag(parse_object(sha1), name, strlen(name));
1499 if (!object)
1500 return NULL;
1501 if (object->type == OBJ_TREE)
1502 return make_virtual_commit((struct tree*)object, name);
1503 if (object->type != OBJ_COMMIT)
1504 return NULL;
1505 if (parse_commit((struct commit *)object))
1506 return NULL;
1507 return (struct commit *)object;
1508}
1509
1510int merge_recursive_generic(struct merge_options *o,
1511 const unsigned char *head,
1512 const unsigned char *merge,
1513 int num_base_list,
1514 const unsigned char **base_list,
1515 struct commit **result)
1516{
1517 int clean, index_fd;
1518 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1519 struct commit *head_commit = get_ref(head, o->branch1);
1520 struct commit *next_commit = get_ref(merge, o->branch2);
1521 struct commit_list *ca = NULL;
1522
1523 if (base_list) {
1524 int i;
1525 for (i = 0; i < num_base_list; ++i) {
1526 struct commit *base;
1527 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1528 return error("Could not parse object '%s'",
1529 sha1_to_hex(base_list[i]));
1530 commit_list_insert(base, &ca);
1531 }
1532 }
1533
1534 index_fd = hold_locked_index(lock, 1);
1535 clean = merge_recursive(o, head_commit, next_commit, ca,
1536 result);
1537 if (active_cache_changed &&
1538 (write_cache(index_fd, active_cache, active_nr) ||
1539 commit_locked_index(lock)))
1540 return error("Unable to write index.");
1541
1542 return clean ? 0 : 1;
1543}
1544
1545static int merge_recursive_config(const char *var, const char *value, void *cb)
1546{
1547 struct merge_options *o = cb;
1548 if (!strcasecmp(var, "merge.verbosity")) {
1549 o->verbosity = git_config_int(var, value);
1550 return 0;
1551 }
1552 if (!strcasecmp(var, "diff.renamelimit")) {
1553 o->diff_rename_limit = git_config_int(var, value);
1554 return 0;
1555 }
1556 if (!strcasecmp(var, "merge.renamelimit")) {
1557 o->merge_rename_limit = git_config_int(var, value);
1558 return 0;
1559 }
1560 return git_xmerge_config(var, value, cb);
1561}
1562
1563void init_merge_options(struct merge_options *o)
1564{
1565 memset(o, 0, sizeof(struct merge_options));
1566 o->verbosity = 2;
1567 o->buffer_output = 1;
1568 o->diff_rename_limit = -1;
1569 o->merge_rename_limit = -1;
1570 o->renormalize = 0;
1571 git_config(merge_recursive_config, o);
1572 if (getenv("GIT_MERGE_VERBOSITY"))
1573 o->verbosity =
1574 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1575 if (o->verbosity >= 5)
1576 o->buffer_output = 0;
1577 strbuf_init(&o->obuf, 0);
1578 memset(&o->current_file_set, 0, sizeof(struct string_list));
1579 o->current_file_set.strdup_strings = 1;
1580 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1581 o->current_directory_set.strdup_strings = 1;
1582}