Merge branch 'maint'
[git] / merge-recursive.c
1 /*
2  * Recursive Merge algorithm stolen from git-merge-recursive.py by
3  * Fredrik Kuivinen.
4  * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5  */
6 #include "cache.h"
7 #include "cache-tree.h"
8 #include "commit.h"
9 #include "blob.h"
10 #include "builtin.h"
11 #include "tree-walk.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "tag.h"
15 #include "unpack-trees.h"
16 #include "string-list.h"
17 #include "xdiff-interface.h"
18 #include "ll-merge.h"
19 #include "attr.h"
20 #include "merge-recursive.h"
21 #include "dir.h"
22
23 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
24 {
25         unsigned char shifted[20];
26
27         /*
28          * NEEDSWORK: this limits the recursion depth to hardcoded
29          * value '2' to avoid excessive overhead.
30          */
31         shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
32         if (!hashcmp(two->object.sha1, shifted))
33                 return two;
34         return lookup_tree(shifted);
35 }
36
37 /*
38  * A virtual commit has (const char *)commit->util set to the name.
39  */
40
41 struct commit *make_virtual_commit(struct tree *tree, const char *comment)
42 {
43         struct commit *commit = xcalloc(1, sizeof(struct commit));
44         commit->tree = tree;
45         commit->util = (void*)comment;
46         /* avoid warnings */
47         commit->object.parsed = 1;
48         return commit;
49 }
50
51 /*
52  * Since we use get_tree_entry(), which does not put the read object into
53  * the object pool, we cannot rely on a == b.
54  */
55 static int sha_eq(const unsigned char *a, const unsigned char *b)
56 {
57         if (!a && !b)
58                 return 2;
59         return a && b && hashcmp(a, b) == 0;
60 }
61
62 /*
63  * Since we want to write the index eventually, we cannot reuse the index
64  * for these (temporary) data.
65  */
66 struct stage_data
67 {
68         struct
69         {
70                 unsigned mode;
71                 unsigned char sha[20];
72         } stages[4];
73         unsigned processed:1;
74 };
75
76 static int show(struct merge_options *o, int v)
77 {
78         return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
79 }
80
81 static void flush_output(struct merge_options *o)
82 {
83         if (o->obuf.len) {
84                 fputs(o->obuf.buf, stdout);
85                 strbuf_reset(&o->obuf);
86         }
87 }
88
89 static void output(struct merge_options *o, int v, const char *fmt, ...)
90 {
91         int len;
92         va_list ap;
93
94         if (!show(o, v))
95                 return;
96
97         strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
98         memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
99         strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
100
101         va_start(ap, fmt);
102         len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
103         va_end(ap);
104
105         if (len < 0)
106                 len = 0;
107         if (len >= strbuf_avail(&o->obuf)) {
108                 strbuf_grow(&o->obuf, len + 2);
109                 va_start(ap, fmt);
110                 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
111                 va_end(ap);
112                 if (len >= strbuf_avail(&o->obuf)) {
113                         die("this should not happen, your snprintf is broken");
114                 }
115         }
116         strbuf_setlen(&o->obuf, o->obuf.len + len);
117         strbuf_add(&o->obuf, "\n", 1);
118         if (!o->buffer_output)
119                 flush_output(o);
120 }
121
122 static void output_commit_title(struct merge_options *o, struct commit *commit)
123 {
124         int i;
125         flush_output(o);
126         for (i = o->call_depth; i--;)
127                 fputs("  ", stdout);
128         if (commit->util)
129                 printf("virtual %s\n", (char *)commit->util);
130         else {
131                 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
132                 if (parse_commit(commit) != 0)
133                         printf("(bad commit)\n");
134                 else {
135                         const char *s;
136                         int len;
137                         for (s = commit->buffer; *s; s++)
138                                 if (*s == '\n' && s[1] == '\n') {
139                                         s += 2;
140                                         break;
141                                 }
142                         for (len = 0; s[len] && '\n' != s[len]; len++)
143                                 ; /* do nothing */
144                         printf("%.*s\n", len, s);
145                 }
146         }
147 }
148
149 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
150                 const char *path, int stage, int refresh, int options)
151 {
152         struct cache_entry *ce;
153         ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
154         if (!ce)
155                 return error("addinfo_cache failed for path '%s'", path);
156         return add_cache_entry(ce, options);
157 }
158
159 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
160 {
161         parse_tree(tree);
162         init_tree_desc(desc, tree->buffer, tree->size);
163 }
164
165 static int git_merge_trees(int index_only,
166                            struct tree *common,
167                            struct tree *head,
168                            struct tree *merge)
169 {
170         int rc;
171         struct tree_desc t[3];
172         struct unpack_trees_options opts;
173
174         memset(&opts, 0, sizeof(opts));
175         if (index_only)
176                 opts.index_only = 1;
177         else
178                 opts.update = 1;
179         opts.merge = 1;
180         opts.head_idx = 2;
181         opts.fn = threeway_merge;
182         opts.src_index = &the_index;
183         opts.dst_index = &the_index;
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
194 struct tree *write_tree_from_memory(struct merge_options *o)
195 {
196         struct tree *result = NULL;
197
198         if (unmerged_cache()) {
199                 int i;
200                 output(o, 0, "There are unmerged index entries:");
201                 for (i = 0; i < active_nr; i++) {
202                         struct cache_entry *ce = active_cache[i];
203                         if (ce_stage(ce))
204                                 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
205                 }
206                 return NULL;
207         }
208
209         if (!active_cache_tree)
210                 active_cache_tree = cache_tree();
211
212         if (!cache_tree_fully_valid(active_cache_tree) &&
213             cache_tree_update(active_cache_tree,
214                               active_cache, active_nr, 0, 0) < 0)
215                 die("error building trees");
216
217         result = lookup_tree(active_cache_tree->sha1);
218
219         return result;
220 }
221
222 static int save_files_dirs(const unsigned char *sha1,
223                 const char *base, int baselen, const char *path,
224                 unsigned int mode, int stage, void *context)
225 {
226         int len = strlen(path);
227         char *newpath = xmalloc(baselen + len + 1);
228         struct merge_options *o = context;
229
230         memcpy(newpath, base, baselen);
231         memcpy(newpath + baselen, path, len);
232         newpath[baselen + len] = '\0';
233
234         if (S_ISDIR(mode))
235                 string_list_insert(newpath, &o->current_directory_set);
236         else
237                 string_list_insert(newpath, &o->current_file_set);
238         free(newpath);
239
240         return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
241 }
242
243 static int get_files_dirs(struct merge_options *o, struct tree *tree)
244 {
245         int n;
246         if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
247                 return 0;
248         n = o->current_file_set.nr + o->current_directory_set.nr;
249         return n;
250 }
251
252 /*
253  * Returns an index_entry instance which doesn't have to correspond to
254  * a real cache entry in Git's index.
255  */
256 static struct stage_data *insert_stage_data(const char *path,
257                 struct tree *o, struct tree *a, struct tree *b,
258                 struct string_list *entries)
259 {
260         struct string_list_item *item;
261         struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
262         get_tree_entry(o->object.sha1, path,
263                         e->stages[1].sha, &e->stages[1].mode);
264         get_tree_entry(a->object.sha1, path,
265                         e->stages[2].sha, &e->stages[2].mode);
266         get_tree_entry(b->object.sha1, path,
267                         e->stages[3].sha, &e->stages[3].mode);
268         item = string_list_insert(path, entries);
269         item->util = e;
270         return e;
271 }
272
273 /*
274  * Create a dictionary mapping file names to stage_data objects. The
275  * dictionary contains one entry for every path with a non-zero stage entry.
276  */
277 static struct string_list *get_unmerged(void)
278 {
279         struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
280         int i;
281
282         unmerged->strdup_strings = 1;
283
284         for (i = 0; i < active_nr; i++) {
285                 struct string_list_item *item;
286                 struct stage_data *e;
287                 struct cache_entry *ce = active_cache[i];
288                 if (!ce_stage(ce))
289                         continue;
290
291                 item = string_list_lookup(ce->name, unmerged);
292                 if (!item) {
293                         item = string_list_insert(ce->name, unmerged);
294                         item->util = xcalloc(1, sizeof(struct stage_data));
295                 }
296                 e = item->util;
297                 e->stages[ce_stage(ce)].mode = ce->ce_mode;
298                 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
299         }
300
301         return unmerged;
302 }
303
304 struct rename
305 {
306         struct diff_filepair *pair;
307         struct stage_data *src_entry;
308         struct stage_data *dst_entry;
309         unsigned processed:1;
310 };
311
312 /*
313  * Get information of all renames which occurred between 'o_tree' and
314  * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
315  * 'b_tree') to be able to associate the correct cache entries with
316  * the rename information. 'tree' is always equal to either a_tree or b_tree.
317  */
318 static struct string_list *get_renames(struct merge_options *o,
319                                        struct tree *tree,
320                                        struct tree *o_tree,
321                                        struct tree *a_tree,
322                                        struct tree *b_tree,
323                                        struct string_list *entries)
324 {
325         int i;
326         struct string_list *renames;
327         struct diff_options opts;
328
329         renames = xcalloc(1, sizeof(struct string_list));
330         diff_setup(&opts);
331         DIFF_OPT_SET(&opts, RECURSIVE);
332         opts.detect_rename = DIFF_DETECT_RENAME;
333         opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
334                             o->diff_rename_limit >= 0 ? o->diff_rename_limit :
335                             500;
336         opts.warn_on_too_large_rename = 1;
337         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
338         if (diff_setup_done(&opts) < 0)
339                 die("diff setup failed");
340         diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
341         diffcore_std(&opts);
342         for (i = 0; i < diff_queued_diff.nr; ++i) {
343                 struct string_list_item *item;
344                 struct rename *re;
345                 struct diff_filepair *pair = diff_queued_diff.queue[i];
346                 if (pair->status != 'R') {
347                         diff_free_filepair(pair);
348                         continue;
349                 }
350                 re = xmalloc(sizeof(*re));
351                 re->processed = 0;
352                 re->pair = pair;
353                 item = string_list_lookup(re->pair->one->path, entries);
354                 if (!item)
355                         re->src_entry = insert_stage_data(re->pair->one->path,
356                                         o_tree, a_tree, b_tree, entries);
357                 else
358                         re->src_entry = item->util;
359
360                 item = string_list_lookup(re->pair->two->path, entries);
361                 if (!item)
362                         re->dst_entry = insert_stage_data(re->pair->two->path,
363                                         o_tree, a_tree, b_tree, entries);
364                 else
365                         re->dst_entry = item->util;
366                 item = string_list_insert(pair->one->path, renames);
367                 item->util = re;
368         }
369         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
370         diff_queued_diff.nr = 0;
371         diff_flush(&opts);
372         return renames;
373 }
374
375 static int update_stages(const char *path, struct diff_filespec *o,
376                          struct diff_filespec *a, struct diff_filespec *b,
377                          int clear)
378 {
379         int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
380         if (clear)
381                 if (remove_file_from_cache(path))
382                         return -1;
383         if (o)
384                 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
385                         return -1;
386         if (a)
387                 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
388                         return -1;
389         if (b)
390                 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
391                         return -1;
392         return 0;
393 }
394
395 static int remove_file(struct merge_options *o, int clean,
396                        const char *path, int no_wd)
397 {
398         int update_cache = o->call_depth || clean;
399         int update_working_directory = !o->call_depth && !no_wd;
400
401         if (update_cache) {
402                 if (remove_file_from_cache(path))
403                         return -1;
404         }
405         if (update_working_directory) {
406                 if (remove_path(path) && errno != ENOENT)
407                         return -1;
408         }
409         return 0;
410 }
411
412 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
413 {
414         char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
415         int suffix = 0;
416         struct stat st;
417         char *p = newpath + strlen(path);
418         strcpy(newpath, path);
419         *(p++) = '~';
420         strcpy(p, branch);
421         for (; *p; ++p)
422                 if ('/' == *p)
423                         *p = '_';
424         while (string_list_has_string(&o->current_file_set, newpath) ||
425                string_list_has_string(&o->current_directory_set, newpath) ||
426                lstat(newpath, &st) == 0)
427                 sprintf(p, "_%d", suffix++);
428
429         string_list_insert(newpath, &o->current_file_set);
430         return newpath;
431 }
432
433 static void flush_buffer(int fd, const char *buf, unsigned long size)
434 {
435         while (size > 0) {
436                 long ret = write_in_full(fd, buf, size);
437                 if (ret < 0) {
438                         /* Ignore epipe */
439                         if (errno == EPIPE)
440                                 break;
441                         die("merge-recursive: %s", strerror(errno));
442                 } else if (!ret) {
443                         die("merge-recursive: disk full?");
444                 }
445                 size -= ret;
446                 buf += ret;
447         }
448 }
449
450 static int would_lose_untracked(const char *path)
451 {
452         int pos = cache_name_pos(path, strlen(path));
453
454         if (pos < 0)
455                 pos = -1 - pos;
456         while (pos < active_nr &&
457                !strcmp(path, active_cache[pos]->name)) {
458                 /*
459                  * If stage #0, it is definitely tracked.
460                  * If it has stage #2 then it was tracked
461                  * before this merge started.  All other
462                  * cases the path was not tracked.
463                  */
464                 switch (ce_stage(active_cache[pos])) {
465                 case 0:
466                 case 2:
467                         return 0;
468                 }
469                 pos++;
470         }
471         return file_exists(path);
472 }
473
474 static int make_room_for_path(const char *path)
475 {
476         int status;
477         const char *msg = "failed to create path '%s'%s";
478
479         status = safe_create_leading_directories_const(path);
480         if (status) {
481                 if (status == -3) {
482                         /* something else exists */
483                         error(msg, path, ": perhaps a D/F conflict?");
484                         return -1;
485                 }
486                 die(msg, path, "");
487         }
488
489         /*
490          * Do not unlink a file in the work tree if we are not
491          * tracking it.
492          */
493         if (would_lose_untracked(path))
494                 return error("refusing to lose untracked file at '%s'",
495                              path);
496
497         /* Successful unlink is good.. */
498         if (!unlink(path))
499                 return 0;
500         /* .. and so is no existing file */
501         if (errno == ENOENT)
502                 return 0;
503         /* .. but not some other error (who really cares what?) */
504         return error(msg, path, ": perhaps a D/F conflict?");
505 }
506
507 static void update_file_flags(struct merge_options *o,
508                               const unsigned char *sha,
509                               unsigned mode,
510                               const char *path,
511                               int update_cache,
512                               int update_wd)
513 {
514         if (o->call_depth)
515                 update_wd = 0;
516
517         if (update_wd) {
518                 enum object_type type;
519                 void *buf;
520                 unsigned long size;
521
522                 if (S_ISGITLINK(mode))
523                         /*
524                          * We may later decide to recursively descend into
525                          * the submodule directory and update its index
526                          * and/or work tree, but we do not do that now.
527                          */
528                         goto update_index;
529
530                 buf = read_sha1_file(sha, &type, &size);
531                 if (!buf)
532                         die("cannot read object %s '%s'", sha1_to_hex(sha), path);
533                 if (type != OBJ_BLOB)
534                         die("blob expected for %s '%s'", sha1_to_hex(sha), path);
535                 if (S_ISREG(mode)) {
536                         struct strbuf strbuf = STRBUF_INIT;
537                         if (convert_to_working_tree(path, buf, size, &strbuf)) {
538                                 free(buf);
539                                 size = strbuf.len;
540                                 buf = strbuf_detach(&strbuf, NULL);
541                         }
542                 }
543
544                 if (make_room_for_path(path) < 0) {
545                         update_wd = 0;
546                         free(buf);
547                         goto update_index;
548                 }
549                 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
550                         int fd;
551                         if (mode & 0100)
552                                 mode = 0777;
553                         else
554                                 mode = 0666;
555                         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
556                         if (fd < 0)
557                                 die("failed to open %s: %s", path, strerror(errno));
558                         flush_buffer(fd, buf, size);
559                         close(fd);
560                 } else if (S_ISLNK(mode)) {
561                         char *lnk = xmemdupz(buf, size);
562                         safe_create_leading_directories_const(path);
563                         unlink(path);
564                         if (symlink(lnk, path))
565                                 die("failed to symlink %s: %s", path, strerror(errno));
566                         free(lnk);
567                 } else
568                         die("do not know what to do with %06o %s '%s'",
569                             mode, sha1_to_hex(sha), path);
570                 free(buf);
571         }
572  update_index:
573         if (update_cache)
574                 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
575 }
576
577 static void update_file(struct merge_options *o,
578                         int clean,
579                         const unsigned char *sha,
580                         unsigned mode,
581                         const char *path)
582 {
583         update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
584 }
585
586 /* Low level file merging, update and removal */
587
588 struct merge_file_info
589 {
590         unsigned char sha[20];
591         unsigned mode;
592         unsigned clean:1,
593                  merge:1;
594 };
595
596 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
597 {
598         unsigned long size;
599         enum object_type type;
600
601         if (!hashcmp(sha1, null_sha1)) {
602                 mm->ptr = xstrdup("");
603                 mm->size = 0;
604                 return;
605         }
606
607         mm->ptr = read_sha1_file(sha1, &type, &size);
608         if (!mm->ptr || type != OBJ_BLOB)
609                 die("unable to read blob object %s", sha1_to_hex(sha1));
610         mm->size = size;
611 }
612
613 static int merge_3way(struct merge_options *o,
614                       mmbuffer_t *result_buf,
615                       struct diff_filespec *one,
616                       struct diff_filespec *a,
617                       struct diff_filespec *b,
618                       const char *branch1,
619                       const char *branch2)
620 {
621         mmfile_t orig, src1, src2;
622         char *name1, *name2;
623         int merge_status;
624
625         name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
626         name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
627
628         fill_mm(one->sha1, &orig);
629         fill_mm(a->sha1, &src1);
630         fill_mm(b->sha1, &src2);
631
632         merge_status = ll_merge(result_buf, a->path, &orig,
633                                 &src1, name1, &src2, name2,
634                                 o->call_depth);
635
636         free(name1);
637         free(name2);
638         free(orig.ptr);
639         free(src1.ptr);
640         free(src2.ptr);
641         return merge_status;
642 }
643
644 static struct merge_file_info merge_file(struct merge_options *o,
645                                          struct diff_filespec *one,
646                                          struct diff_filespec *a,
647                                          struct diff_filespec *b,
648                                          const char *branch1,
649                                          const char *branch2)
650 {
651         struct merge_file_info result;
652         result.merge = 0;
653         result.clean = 1;
654
655         if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
656                 result.clean = 0;
657                 if (S_ISREG(a->mode)) {
658                         result.mode = a->mode;
659                         hashcpy(result.sha, a->sha1);
660                 } else {
661                         result.mode = b->mode;
662                         hashcpy(result.sha, b->sha1);
663                 }
664         } else {
665                 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
666                         result.merge = 1;
667
668                 /*
669                  * Merge modes
670                  */
671                 if (a->mode == b->mode || a->mode == one->mode)
672                         result.mode = b->mode;
673                 else {
674                         result.mode = a->mode;
675                         if (b->mode != one->mode) {
676                                 result.clean = 0;
677                                 result.merge = 1;
678                         }
679                 }
680
681                 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
682                         hashcpy(result.sha, b->sha1);
683                 else if (sha_eq(b->sha1, one->sha1))
684                         hashcpy(result.sha, a->sha1);
685                 else if (S_ISREG(a->mode)) {
686                         mmbuffer_t result_buf;
687                         int merge_status;
688
689                         merge_status = merge_3way(o, &result_buf, one, a, b,
690                                                   branch1, branch2);
691
692                         if ((merge_status < 0) || !result_buf.ptr)
693                                 die("Failed to execute internal merge");
694
695                         if (write_sha1_file(result_buf.ptr, result_buf.size,
696                                             blob_type, result.sha))
697                                 die("Unable to add %s to database",
698                                     a->path);
699
700                         free(result_buf.ptr);
701                         result.clean = (merge_status == 0);
702                 } else if (S_ISGITLINK(a->mode)) {
703                         result.clean = 0;
704                         hashcpy(result.sha, a->sha1);
705                 } else if (S_ISLNK(a->mode)) {
706                         hashcpy(result.sha, a->sha1);
707
708                         if (!sha_eq(a->sha1, b->sha1))
709                                 result.clean = 0;
710                 } else {
711                         die("unsupported object type in the tree");
712                 }
713         }
714
715         return result;
716 }
717
718 static void conflict_rename_rename(struct merge_options *o,
719                                    struct rename *ren1,
720                                    const char *branch1,
721                                    struct rename *ren2,
722                                    const char *branch2)
723 {
724         char *del[2];
725         int delp = 0;
726         const char *ren1_dst = ren1->pair->two->path;
727         const char *ren2_dst = ren2->pair->two->path;
728         const char *dst_name1 = ren1_dst;
729         const char *dst_name2 = ren2_dst;
730         if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
731                 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
732                 output(o, 1, "%s is a directory in %s adding as %s instead",
733                        ren1_dst, branch2, dst_name1);
734                 remove_file(o, 0, ren1_dst, 0);
735         }
736         if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
737                 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
738                 output(o, 1, "%s is a directory in %s adding as %s instead",
739                        ren2_dst, branch1, dst_name2);
740                 remove_file(o, 0, ren2_dst, 0);
741         }
742         if (o->call_depth) {
743                 remove_file_from_cache(dst_name1);
744                 remove_file_from_cache(dst_name2);
745                 /*
746                  * Uncomment to leave the conflicting names in the resulting tree
747                  *
748                  * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
749                  * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
750                  */
751         } else {
752                 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
753                 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
754         }
755         while (delp--)
756                 free(del[delp]);
757 }
758
759 static void conflict_rename_dir(struct merge_options *o,
760                                 struct rename *ren1,
761                                 const char *branch1)
762 {
763         char *new_path = unique_path(o, ren1->pair->two->path, branch1);
764         output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
765         remove_file(o, 0, ren1->pair->two->path, 0);
766         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
767         free(new_path);
768 }
769
770 static void conflict_rename_rename_2(struct merge_options *o,
771                                      struct rename *ren1,
772                                      const char *branch1,
773                                      struct rename *ren2,
774                                      const char *branch2)
775 {
776         char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
777         char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
778         output(o, 1, "Renaming %s to %s and %s to %s instead",
779                ren1->pair->one->path, new_path1,
780                ren2->pair->one->path, new_path2);
781         remove_file(o, 0, ren1->pair->two->path, 0);
782         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
783         update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
784         free(new_path2);
785         free(new_path1);
786 }
787
788 static int process_renames(struct merge_options *o,
789                            struct string_list *a_renames,
790                            struct string_list *b_renames)
791 {
792         int clean_merge = 1, i, j;
793         struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
794         const struct rename *sre;
795
796         for (i = 0; i < a_renames->nr; i++) {
797                 sre = a_renames->items[i].util;
798                 string_list_insert(sre->pair->two->path, &a_by_dst)->util
799                         = sre->dst_entry;
800         }
801         for (i = 0; i < b_renames->nr; i++) {
802                 sre = b_renames->items[i].util;
803                 string_list_insert(sre->pair->two->path, &b_by_dst)->util
804                         = sre->dst_entry;
805         }
806
807         for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
808                 char *src;
809                 struct string_list *renames1, *renames2Dst;
810                 struct rename *ren1 = NULL, *ren2 = NULL;
811                 const char *branch1, *branch2;
812                 const char *ren1_src, *ren1_dst;
813
814                 if (i >= a_renames->nr) {
815                         ren2 = b_renames->items[j++].util;
816                 } else if (j >= b_renames->nr) {
817                         ren1 = a_renames->items[i++].util;
818                 } else {
819                         int compare = strcmp(a_renames->items[i].string,
820                                              b_renames->items[j].string);
821                         if (compare <= 0)
822                                 ren1 = a_renames->items[i++].util;
823                         if (compare >= 0)
824                                 ren2 = b_renames->items[j++].util;
825                 }
826
827                 /* TODO: refactor, so that 1/2 are not needed */
828                 if (ren1) {
829                         renames1 = a_renames;
830                         renames2Dst = &b_by_dst;
831                         branch1 = o->branch1;
832                         branch2 = o->branch2;
833                 } else {
834                         struct rename *tmp;
835                         renames1 = b_renames;
836                         renames2Dst = &a_by_dst;
837                         branch1 = o->branch2;
838                         branch2 = o->branch1;
839                         tmp = ren2;
840                         ren2 = ren1;
841                         ren1 = tmp;
842                 }
843                 src = ren1->pair->one->path;
844
845                 ren1->dst_entry->processed = 1;
846                 ren1->src_entry->processed = 1;
847
848                 if (ren1->processed)
849                         continue;
850                 ren1->processed = 1;
851
852                 ren1_src = ren1->pair->one->path;
853                 ren1_dst = ren1->pair->two->path;
854
855                 if (ren2) {
856                         const char *ren2_src = ren2->pair->one->path;
857                         const char *ren2_dst = ren2->pair->two->path;
858                         /* Renamed in 1 and renamed in 2 */
859                         if (strcmp(ren1_src, ren2_src) != 0)
860                                 die("ren1.src != ren2.src");
861                         ren2->dst_entry->processed = 1;
862                         ren2->processed = 1;
863                         if (strcmp(ren1_dst, ren2_dst) != 0) {
864                                 clean_merge = 0;
865                                 output(o, 1, "CONFLICT (rename/rename): "
866                                        "Rename \"%s\"->\"%s\" in branch \"%s\" "
867                                        "rename \"%s\"->\"%s\" in \"%s\"%s",
868                                        src, ren1_dst, branch1,
869                                        src, ren2_dst, branch2,
870                                        o->call_depth ? " (left unresolved)": "");
871                                 if (o->call_depth) {
872                                         remove_file_from_cache(src);
873                                         update_file(o, 0, ren1->pair->one->sha1,
874                                                     ren1->pair->one->mode, src);
875                                 }
876                                 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
877                         } else {
878                                 struct merge_file_info mfi;
879                                 remove_file(o, 1, ren1_src, 1);
880                                 mfi = merge_file(o,
881                                                  ren1->pair->one,
882                                                  ren1->pair->two,
883                                                  ren2->pair->two,
884                                                  branch1,
885                                                  branch2);
886                                 if (mfi.merge || !mfi.clean)
887                                         output(o, 1, "Renaming %s->%s", src, ren1_dst);
888
889                                 if (mfi.merge)
890                                         output(o, 2, "Auto-merging %s", ren1_dst);
891
892                                 if (!mfi.clean) {
893                                         output(o, 1, "CONFLICT (content): merge conflict in %s",
894                                                ren1_dst);
895                                         clean_merge = 0;
896
897                                         if (!o->call_depth)
898                                                 update_stages(ren1_dst,
899                                                               ren1->pair->one,
900                                                               ren1->pair->two,
901                                                               ren2->pair->two,
902                                                               1 /* clear */);
903                                 }
904                                 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
905                         }
906                 } else {
907                         /* Renamed in 1, maybe changed in 2 */
908                         struct string_list_item *item;
909                         /* we only use sha1 and mode of these */
910                         struct diff_filespec src_other, dst_other;
911                         int try_merge, stage = a_renames == renames1 ? 3: 2;
912
913                         remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
914
915                         hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
916                         src_other.mode = ren1->src_entry->stages[stage].mode;
917                         hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
918                         dst_other.mode = ren1->dst_entry->stages[stage].mode;
919
920                         try_merge = 0;
921
922                         if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
923                                 clean_merge = 0;
924                                 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
925                                        " directory %s added in %s",
926                                        ren1_src, ren1_dst, branch1,
927                                        ren1_dst, branch2);
928                                 conflict_rename_dir(o, ren1, branch1);
929                         } else if (sha_eq(src_other.sha1, null_sha1)) {
930                                 clean_merge = 0;
931                                 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
932                                        "and deleted in %s",
933                                        ren1_src, ren1_dst, branch1,
934                                        branch2);
935                                 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
936                                 if (!o->call_depth)
937                                         update_stages(ren1_dst, NULL,
938                                                         branch1 == o->branch1 ?
939                                                         ren1->pair->two : NULL,
940                                                         branch1 == o->branch1 ?
941                                                         NULL : ren1->pair->two, 1);
942                         } else if (!sha_eq(dst_other.sha1, null_sha1)) {
943                                 const char *new_path;
944                                 clean_merge = 0;
945                                 try_merge = 1;
946                                 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
947                                        "%s added in %s",
948                                        ren1_src, ren1_dst, branch1,
949                                        ren1_dst, branch2);
950                                 new_path = unique_path(o, ren1_dst, branch2);
951                                 output(o, 1, "Adding as %s instead", new_path);
952                                 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
953                         } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
954                                 ren2 = item->util;
955                                 clean_merge = 0;
956                                 ren2->processed = 1;
957                                 output(o, 1, "CONFLICT (rename/rename): "
958                                        "Rename %s->%s in %s. "
959                                        "Rename %s->%s in %s",
960                                        ren1_src, ren1_dst, branch1,
961                                        ren2->pair->one->path, ren2->pair->two->path, branch2);
962                                 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
963                         } else
964                                 try_merge = 1;
965
966                         if (try_merge) {
967                                 struct diff_filespec *one, *a, *b;
968                                 struct merge_file_info mfi;
969                                 src_other.path = (char *)ren1_src;
970
971                                 one = ren1->pair->one;
972                                 if (a_renames == renames1) {
973                                         a = ren1->pair->two;
974                                         b = &src_other;
975                                 } else {
976                                         b = ren1->pair->two;
977                                         a = &src_other;
978                                 }
979                                 mfi = merge_file(o, one, a, b,
980                                                 o->branch1, o->branch2);
981
982                                 if (mfi.clean &&
983                                     sha_eq(mfi.sha, ren1->pair->two->sha1) &&
984                                     mfi.mode == ren1->pair->two->mode)
985                                         /*
986                                          * This messaged is part of
987                                          * t6022 test. If you change
988                                          * it update the test too.
989                                          */
990                                         output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
991                                 else {
992                                         if (mfi.merge || !mfi.clean)
993                                                 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
994                                         if (mfi.merge)
995                                                 output(o, 2, "Auto-merging %s", ren1_dst);
996                                         if (!mfi.clean) {
997                                                 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
998                                                        ren1_dst);
999                                                 clean_merge = 0;
1000
1001                                                 if (!o->call_depth)
1002                                                         update_stages(ren1_dst,
1003                                                                       one, a, b, 1);
1004                                         }
1005                                         update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1006                                 }
1007                         }
1008                 }
1009         }
1010         string_list_clear(&a_by_dst, 0);
1011         string_list_clear(&b_by_dst, 0);
1012
1013         return clean_merge;
1014 }
1015
1016 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1017 {
1018         return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1019 }
1020
1021 /* Per entry merge function */
1022 static int process_entry(struct merge_options *o,
1023                          const char *path, struct stage_data *entry)
1024 {
1025         /*
1026         printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1027         print_index_entry("\tpath: ", entry);
1028         */
1029         int clean_merge = 1;
1030         unsigned o_mode = entry->stages[1].mode;
1031         unsigned a_mode = entry->stages[2].mode;
1032         unsigned b_mode = entry->stages[3].mode;
1033         unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1034         unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1035         unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1036
1037         if (o_sha && (!a_sha || !b_sha)) {
1038                 /* Case A: Deleted in one */
1039                 if ((!a_sha && !b_sha) ||
1040                     (sha_eq(a_sha, o_sha) && !b_sha) ||
1041                     (!a_sha && sha_eq(b_sha, o_sha))) {
1042                         /* Deleted in both or deleted in one and
1043                          * unchanged in the other */
1044                         if (a_sha)
1045                                 output(o, 2, "Removing %s", path);
1046                         /* do not touch working file if it did not exist */
1047                         remove_file(o, 1, path, !a_sha);
1048                 } else {
1049                         /* Deleted in one and changed in the other */
1050                         clean_merge = 0;
1051                         if (!a_sha) {
1052                                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1053                                        "and modified in %s. Version %s of %s left in tree.",
1054                                        path, o->branch1,
1055                                        o->branch2, o->branch2, path);
1056                                 update_file(o, 0, b_sha, b_mode, path);
1057                         } else {
1058                                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1059                                        "and modified in %s. Version %s of %s left in tree.",
1060                                        path, o->branch2,
1061                                        o->branch1, o->branch1, path);
1062                                 update_file(o, 0, a_sha, a_mode, path);
1063                         }
1064                 }
1065
1066         } else if ((!o_sha && a_sha && !b_sha) ||
1067                    (!o_sha && !a_sha && b_sha)) {
1068                 /* Case B: Added in one. */
1069                 const char *add_branch;
1070                 const char *other_branch;
1071                 unsigned mode;
1072                 const unsigned char *sha;
1073                 const char *conf;
1074
1075                 if (a_sha) {
1076                         add_branch = o->branch1;
1077                         other_branch = o->branch2;
1078                         mode = a_mode;
1079                         sha = a_sha;
1080                         conf = "file/directory";
1081                 } else {
1082                         add_branch = o->branch2;
1083                         other_branch = o->branch1;
1084                         mode = b_mode;
1085                         sha = b_sha;
1086                         conf = "directory/file";
1087                 }
1088                 if (string_list_has_string(&o->current_directory_set, path)) {
1089                         const char *new_path = unique_path(o, path, add_branch);
1090                         clean_merge = 0;
1091                         output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1092                                "Adding %s as %s",
1093                                conf, path, other_branch, path, new_path);
1094                         remove_file(o, 0, path, 0);
1095                         update_file(o, 0, sha, mode, new_path);
1096                 } else {
1097                         output(o, 2, "Adding %s", path);
1098                         update_file(o, 1, sha, mode, path);
1099                 }
1100         } else if (a_sha && b_sha) {
1101                 /* Case C: Added in both (check for same permissions) and */
1102                 /* case D: Modified in both, but differently. */
1103                 const char *reason = "content";
1104                 struct merge_file_info mfi;
1105                 struct diff_filespec one, a, b;
1106
1107                 if (!o_sha) {
1108                         reason = "add/add";
1109                         o_sha = (unsigned char *)null_sha1;
1110                 }
1111                 output(o, 2, "Auto-merging %s", path);
1112                 one.path = a.path = b.path = (char *)path;
1113                 hashcpy(one.sha1, o_sha);
1114                 one.mode = o_mode;
1115                 hashcpy(a.sha1, a_sha);
1116                 a.mode = a_mode;
1117                 hashcpy(b.sha1, b_sha);
1118                 b.mode = b_mode;
1119
1120                 mfi = merge_file(o, &one, &a, &b,
1121                                  o->branch1, o->branch2);
1122
1123                 clean_merge = mfi.clean;
1124                 if (!mfi.clean) {
1125                         if (S_ISGITLINK(mfi.mode))
1126                                 reason = "submodule";
1127                         output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1128                                         reason, path);
1129                 }
1130                 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1131         } else if (!o_sha && !a_sha && !b_sha) {
1132                 /*
1133                  * this entry was deleted altogether. a_mode == 0 means
1134                  * we had that path and want to actively remove it.
1135                  */
1136                 remove_file(o, 1, path, !a_mode);
1137         } else
1138                 die("Fatal merge failure, shouldn't happen.");
1139
1140         return clean_merge;
1141 }
1142
1143 int merge_trees(struct merge_options *o,
1144                 struct tree *head,
1145                 struct tree *merge,
1146                 struct tree *common,
1147                 struct tree **result)
1148 {
1149         int code, clean;
1150
1151         if (o->subtree_merge) {
1152                 merge = shift_tree_object(head, merge);
1153                 common = shift_tree_object(head, common);
1154         }
1155
1156         if (sha_eq(common->object.sha1, merge->object.sha1)) {
1157                 output(o, 0, "Already uptodate!");
1158                 *result = head;
1159                 return 1;
1160         }
1161
1162         code = git_merge_trees(o->call_depth, common, head, merge);
1163
1164         if (code != 0)
1165                 die("merging of trees %s and %s failed",
1166                     sha1_to_hex(head->object.sha1),
1167                     sha1_to_hex(merge->object.sha1));
1168
1169         if (unmerged_cache()) {
1170                 struct string_list *entries, *re_head, *re_merge;
1171                 int i;
1172                 string_list_clear(&o->current_file_set, 1);
1173                 string_list_clear(&o->current_directory_set, 1);
1174                 get_files_dirs(o, head);
1175                 get_files_dirs(o, merge);
1176
1177                 entries = get_unmerged();
1178                 re_head  = get_renames(o, head, common, head, merge, entries);
1179                 re_merge = get_renames(o, merge, common, head, merge, entries);
1180                 clean = process_renames(o, re_head, re_merge);
1181                 for (i = 0; i < entries->nr; i++) {
1182                         const char *path = entries->items[i].string;
1183                         struct stage_data *e = entries->items[i].util;
1184                         if (!e->processed
1185                                 && !process_entry(o, path, e))
1186                                 clean = 0;
1187                 }
1188
1189                 string_list_clear(re_merge, 0);
1190                 string_list_clear(re_head, 0);
1191                 string_list_clear(entries, 1);
1192
1193         }
1194         else
1195                 clean = 1;
1196
1197         if (o->call_depth)
1198                 *result = write_tree_from_memory(o);
1199
1200         return clean;
1201 }
1202
1203 static struct commit_list *reverse_commit_list(struct commit_list *list)
1204 {
1205         struct commit_list *next = NULL, *current, *backup;
1206         for (current = list; current; current = backup) {
1207                 backup = current->next;
1208                 current->next = next;
1209                 next = current;
1210         }
1211         return next;
1212 }
1213
1214 /*
1215  * Merge the commits h1 and h2, return the resulting virtual
1216  * commit object and a flag indicating the cleanness of the merge.
1217  */
1218 int merge_recursive(struct merge_options *o,
1219                     struct commit *h1,
1220                     struct commit *h2,
1221                     struct commit_list *ca,
1222                     struct commit **result)
1223 {
1224         struct commit_list *iter;
1225         struct commit *merged_common_ancestors;
1226         struct tree *mrtree = mrtree;
1227         int clean;
1228
1229         if (show(o, 4)) {
1230                 output(o, 4, "Merging:");
1231                 output_commit_title(o, h1);
1232                 output_commit_title(o, h2);
1233         }
1234
1235         if (!ca) {
1236                 ca = get_merge_bases(h1, h2, 1);
1237                 ca = reverse_commit_list(ca);
1238         }
1239
1240         if (show(o, 5)) {
1241                 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1242                 for (iter = ca; iter; iter = iter->next)
1243                         output_commit_title(o, iter->item);
1244         }
1245
1246         merged_common_ancestors = pop_commit(&ca);
1247         if (merged_common_ancestors == NULL) {
1248                 /* if there is no common ancestor, make an empty tree */
1249                 struct tree *tree = xcalloc(1, sizeof(struct tree));
1250
1251                 tree->object.parsed = 1;
1252                 tree->object.type = OBJ_TREE;
1253                 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1254                 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1255         }
1256
1257         for (iter = ca; iter; iter = iter->next) {
1258                 const char *saved_b1, *saved_b2;
1259                 o->call_depth++;
1260                 /*
1261                  * When the merge fails, the result contains files
1262                  * with conflict markers. The cleanness flag is
1263                  * ignored, it was never actually used, as result of
1264                  * merge_trees has always overwritten it: the committed
1265                  * "conflicts" were already resolved.
1266                  */
1267                 discard_cache();
1268                 saved_b1 = o->branch1;
1269                 saved_b2 = o->branch2;
1270                 o->branch1 = "Temporary merge branch 1";
1271                 o->branch2 = "Temporary merge branch 2";
1272                 merge_recursive(o, merged_common_ancestors, iter->item,
1273                                 NULL, &merged_common_ancestors);
1274                 o->branch1 = saved_b1;
1275                 o->branch2 = saved_b2;
1276                 o->call_depth--;
1277
1278                 if (!merged_common_ancestors)
1279                         die("merge returned no commit");
1280         }
1281
1282         discard_cache();
1283         if (!o->call_depth)
1284                 read_cache();
1285
1286         clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1287                             &mrtree);
1288
1289         if (o->call_depth) {
1290                 *result = make_virtual_commit(mrtree, "merged tree");
1291                 commit_list_insert(h1, &(*result)->parents);
1292                 commit_list_insert(h2, &(*result)->parents->next);
1293         }
1294         flush_output(o);
1295         return clean;
1296 }
1297
1298 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1299 {
1300         struct object *object;
1301
1302         object = deref_tag(parse_object(sha1), name, strlen(name));
1303         if (!object)
1304                 return NULL;
1305         if (object->type == OBJ_TREE)
1306                 return make_virtual_commit((struct tree*)object, name);
1307         if (object->type != OBJ_COMMIT)
1308                 return NULL;
1309         if (parse_commit((struct commit *)object))
1310                 return NULL;
1311         return (struct commit *)object;
1312 }
1313
1314 int merge_recursive_generic(struct merge_options *o,
1315                             const unsigned char *head,
1316                             const unsigned char *merge,
1317                             int num_base_list,
1318                             const unsigned char **base_list,
1319                             struct commit **result)
1320 {
1321         int clean, index_fd;
1322         struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1323         struct commit *head_commit = get_ref(head, o->branch1);
1324         struct commit *next_commit = get_ref(merge, o->branch2);
1325         struct commit_list *ca = NULL;
1326
1327         if (base_list) {
1328                 int i;
1329                 for (i = 0; i < num_base_list; ++i) {
1330                         struct commit *base;
1331                         if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1332                                 return error("Could not parse object '%s'",
1333                                         sha1_to_hex(base_list[i]));
1334                         commit_list_insert(base, &ca);
1335                 }
1336         }
1337
1338         index_fd = hold_locked_index(lock, 1);
1339         clean = merge_recursive(o, head_commit, next_commit, ca,
1340                         result);
1341         if (active_cache_changed &&
1342                         (write_cache(index_fd, active_cache, active_nr) ||
1343                          commit_locked_index(lock)))
1344                 return error("Unable to write index.");
1345
1346         return clean ? 0 : 1;
1347 }
1348
1349 static int merge_recursive_config(const char *var, const char *value, void *cb)
1350 {
1351         struct merge_options *o = cb;
1352         if (!strcasecmp(var, "merge.verbosity")) {
1353                 o->verbosity = git_config_int(var, value);
1354                 return 0;
1355         }
1356         if (!strcasecmp(var, "diff.renamelimit")) {
1357                 o->diff_rename_limit = git_config_int(var, value);
1358                 return 0;
1359         }
1360         if (!strcasecmp(var, "merge.renamelimit")) {
1361                 o->merge_rename_limit = git_config_int(var, value);
1362                 return 0;
1363         }
1364         return git_xmerge_config(var, value, cb);
1365 }
1366
1367 void init_merge_options(struct merge_options *o)
1368 {
1369         memset(o, 0, sizeof(struct merge_options));
1370         o->verbosity = 2;
1371         o->buffer_output = 1;
1372         o->diff_rename_limit = -1;
1373         o->merge_rename_limit = -1;
1374         git_config(merge_recursive_config, o);
1375         if (getenv("GIT_MERGE_VERBOSITY"))
1376                 o->verbosity =
1377                         strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1378         if (o->verbosity >= 5)
1379                 o->buffer_output = 0;
1380         strbuf_init(&o->obuf, 0);
1381         memset(&o->current_file_set, 0, sizeof(struct string_list));
1382         o->current_file_set.strdup_strings = 1;
1383         memset(&o->current_directory_set, 0, sizeof(struct string_list));
1384         o->current_directory_set.strdup_strings = 1;
1385 }