merge-recursive: get rid of virtual_id
[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 "interpolate.h"
20 #include "attr.h"
21 #include "merge-recursive.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 READ_TREE_RECURSIVE;
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_path(const char *name)
396 {
397         int ret;
398         char *slash, *dirs;
399
400         ret = unlink(name);
401         if (ret)
402                 return ret;
403         dirs = xstrdup(name);
404         while ((slash = strrchr(name, '/'))) {
405                 *slash = '\0';
406                 if (rmdir(name) != 0)
407                         break;
408         }
409         free(dirs);
410         return ret;
411 }
412
413 static int remove_file(struct merge_options *o, int clean,
414                        const char *path, int no_wd)
415 {
416         int update_cache = o->call_depth || clean;
417         int update_working_directory = !o->call_depth && !no_wd;
418
419         if (update_cache) {
420                 if (remove_file_from_cache(path))
421                         return -1;
422         }
423         if (update_working_directory) {
424                 unlink(path);
425                 if (errno != ENOENT || errno != EISDIR)
426                         return -1;
427                 remove_path(path);
428         }
429         return 0;
430 }
431
432 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
433 {
434         char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
435         int suffix = 0;
436         struct stat st;
437         char *p = newpath + strlen(path);
438         strcpy(newpath, path);
439         *(p++) = '~';
440         strcpy(p, branch);
441         for (; *p; ++p)
442                 if ('/' == *p)
443                         *p = '_';
444         while (string_list_has_string(&o->current_file_set, newpath) ||
445                string_list_has_string(&o->current_directory_set, newpath) ||
446                lstat(newpath, &st) == 0)
447                 sprintf(p, "_%d", suffix++);
448
449         string_list_insert(newpath, &o->current_file_set);
450         return newpath;
451 }
452
453 static void flush_buffer(int fd, const char *buf, unsigned long size)
454 {
455         while (size > 0) {
456                 long ret = write_in_full(fd, buf, size);
457                 if (ret < 0) {
458                         /* Ignore epipe */
459                         if (errno == EPIPE)
460                                 break;
461                         die("merge-recursive: %s", strerror(errno));
462                 } else if (!ret) {
463                         die("merge-recursive: disk full?");
464                 }
465                 size -= ret;
466                 buf += ret;
467         }
468 }
469
470 static int make_room_for_path(const char *path)
471 {
472         int status;
473         const char *msg = "failed to create path '%s'%s";
474
475         status = safe_create_leading_directories_const(path);
476         if (status) {
477                 if (status == -3) {
478                         /* something else exists */
479                         error(msg, path, ": perhaps a D/F conflict?");
480                         return -1;
481                 }
482                 die(msg, path, "");
483         }
484
485         /* Successful unlink is good.. */
486         if (!unlink(path))
487                 return 0;
488         /* .. and so is no existing file */
489         if (errno == ENOENT)
490                 return 0;
491         /* .. but not some other error (who really cares what?) */
492         return error(msg, path, ": perhaps a D/F conflict?");
493 }
494
495 static void update_file_flags(struct merge_options *o,
496                               const unsigned char *sha,
497                               unsigned mode,
498                               const char *path,
499                               int update_cache,
500                               int update_wd)
501 {
502         if (o->call_depth)
503                 update_wd = 0;
504
505         if (update_wd) {
506                 enum object_type type;
507                 void *buf;
508                 unsigned long size;
509
510                 if (S_ISGITLINK(mode))
511                         die("cannot read object %s '%s': It is a submodule!",
512                             sha1_to_hex(sha), path);
513
514                 buf = read_sha1_file(sha, &type, &size);
515                 if (!buf)
516                         die("cannot read object %s '%s'", sha1_to_hex(sha), path);
517                 if (type != OBJ_BLOB)
518                         die("blob expected for %s '%s'", sha1_to_hex(sha), path);
519                 if (S_ISREG(mode)) {
520                         struct strbuf strbuf;
521                         strbuf_init(&strbuf, 0);
522                         if (convert_to_working_tree(path, buf, size, &strbuf)) {
523                                 free(buf);
524                                 size = strbuf.len;
525                                 buf = strbuf_detach(&strbuf, NULL);
526                         }
527                 }
528
529                 if (make_room_for_path(path) < 0) {
530                         update_wd = 0;
531                         free(buf);
532                         goto update_index;
533                 }
534                 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
535                         int fd;
536                         if (mode & 0100)
537                                 mode = 0777;
538                         else
539                                 mode = 0666;
540                         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
541                         if (fd < 0)
542                                 die("failed to open %s: %s", path, strerror(errno));
543                         flush_buffer(fd, buf, size);
544                         close(fd);
545                 } else if (S_ISLNK(mode)) {
546                         char *lnk = xmemdupz(buf, size);
547                         safe_create_leading_directories_const(path);
548                         unlink(path);
549                         symlink(lnk, path);
550                         free(lnk);
551                 } else
552                         die("do not know what to do with %06o %s '%s'",
553                             mode, sha1_to_hex(sha), path);
554                 free(buf);
555         }
556  update_index:
557         if (update_cache)
558                 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
559 }
560
561 static void update_file(struct merge_options *o,
562                         int clean,
563                         const unsigned char *sha,
564                         unsigned mode,
565                         const char *path)
566 {
567         update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
568 }
569
570 /* Low level file merging, update and removal */
571
572 struct merge_file_info
573 {
574         unsigned char sha[20];
575         unsigned mode;
576         unsigned clean:1,
577                  merge:1;
578 };
579
580 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
581 {
582         unsigned long size;
583         enum object_type type;
584
585         if (!hashcmp(sha1, null_sha1)) {
586                 mm->ptr = xstrdup("");
587                 mm->size = 0;
588                 return;
589         }
590
591         mm->ptr = read_sha1_file(sha1, &type, &size);
592         if (!mm->ptr || type != OBJ_BLOB)
593                 die("unable to read blob object %s", sha1_to_hex(sha1));
594         mm->size = size;
595 }
596
597 static int merge_3way(struct merge_options *o,
598                       mmbuffer_t *result_buf,
599                       struct diff_filespec *one,
600                       struct diff_filespec *a,
601                       struct diff_filespec *b,
602                       const char *branch1,
603                       const char *branch2)
604 {
605         mmfile_t orig, src1, src2;
606         char *name1, *name2;
607         int merge_status;
608
609         name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
610         name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
611
612         fill_mm(one->sha1, &orig);
613         fill_mm(a->sha1, &src1);
614         fill_mm(b->sha1, &src2);
615
616         merge_status = ll_merge(result_buf, a->path, &orig,
617                                 &src1, name1, &src2, name2,
618                                 o->call_depth);
619
620         free(name1);
621         free(name2);
622         free(orig.ptr);
623         free(src1.ptr);
624         free(src2.ptr);
625         return merge_status;
626 }
627
628 static struct merge_file_info merge_file(struct merge_options *o,
629                                          struct diff_filespec *one,
630                                          struct diff_filespec *a,
631                                          struct diff_filespec *b,
632                                          const char *branch1,
633                                          const char *branch2)
634 {
635         struct merge_file_info result;
636         result.merge = 0;
637         result.clean = 1;
638
639         if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
640                 result.clean = 0;
641                 if (S_ISREG(a->mode)) {
642                         result.mode = a->mode;
643                         hashcpy(result.sha, a->sha1);
644                 } else {
645                         result.mode = b->mode;
646                         hashcpy(result.sha, b->sha1);
647                 }
648         } else {
649                 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
650                         result.merge = 1;
651
652                 /*
653                  * Merge modes
654                  */
655                 if (a->mode == b->mode || a->mode == one->mode)
656                         result.mode = b->mode;
657                 else {
658                         result.mode = a->mode;
659                         if (b->mode != one->mode) {
660                                 result.clean = 0;
661                                 result.merge = 1;
662                         }
663                 }
664
665                 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
666                         hashcpy(result.sha, b->sha1);
667                 else if (sha_eq(b->sha1, one->sha1))
668                         hashcpy(result.sha, a->sha1);
669                 else if (S_ISREG(a->mode)) {
670                         mmbuffer_t result_buf;
671                         int merge_status;
672
673                         merge_status = merge_3way(o, &result_buf, one, a, b,
674                                                   branch1, branch2);
675
676                         if ((merge_status < 0) || !result_buf.ptr)
677                                 die("Failed to execute internal merge");
678
679                         if (write_sha1_file(result_buf.ptr, result_buf.size,
680                                             blob_type, result.sha))
681                                 die("Unable to add %s to database",
682                                     a->path);
683
684                         free(result_buf.ptr);
685                         result.clean = (merge_status == 0);
686                 } else if (S_ISGITLINK(a->mode)) {
687                         result.clean = 0;
688                         hashcpy(result.sha, a->sha1);
689                 } else if (S_ISLNK(a->mode)) {
690                         hashcpy(result.sha, a->sha1);
691
692                         if (!sha_eq(a->sha1, b->sha1))
693                                 result.clean = 0;
694                 } else {
695                         die("unsupported object type in the tree");
696                 }
697         }
698
699         return result;
700 }
701
702 static void conflict_rename_rename(struct merge_options *o,
703                                    struct rename *ren1,
704                                    const char *branch1,
705                                    struct rename *ren2,
706                                    const char *branch2)
707 {
708         char *del[2];
709         int delp = 0;
710         const char *ren1_dst = ren1->pair->two->path;
711         const char *ren2_dst = ren2->pair->two->path;
712         const char *dst_name1 = ren1_dst;
713         const char *dst_name2 = ren2_dst;
714         if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
715                 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
716                 output(o, 1, "%s is a directory in %s adding as %s instead",
717                        ren1_dst, branch2, dst_name1);
718                 remove_file(o, 0, ren1_dst, 0);
719         }
720         if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
721                 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
722                 output(o, 1, "%s is a directory in %s adding as %s instead",
723                        ren2_dst, branch1, dst_name2);
724                 remove_file(o, 0, ren2_dst, 0);
725         }
726         if (o->call_depth) {
727                 remove_file_from_cache(dst_name1);
728                 remove_file_from_cache(dst_name2);
729                 /*
730                  * Uncomment to leave the conflicting names in the resulting tree
731                  *
732                  * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
733                  * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
734                  */
735         } else {
736                 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
737                 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
738         }
739         while (delp--)
740                 free(del[delp]);
741 }
742
743 static void conflict_rename_dir(struct merge_options *o,
744                                 struct rename *ren1,
745                                 const char *branch1)
746 {
747         char *new_path = unique_path(o, ren1->pair->two->path, branch1);
748         output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
749         remove_file(o, 0, ren1->pair->two->path, 0);
750         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
751         free(new_path);
752 }
753
754 static void conflict_rename_rename_2(struct merge_options *o,
755                                      struct rename *ren1,
756                                      const char *branch1,
757                                      struct rename *ren2,
758                                      const char *branch2)
759 {
760         char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
761         char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
762         output(o, 1, "Renaming %s to %s and %s to %s instead",
763                ren1->pair->one->path, new_path1,
764                ren2->pair->one->path, new_path2);
765         remove_file(o, 0, ren1->pair->two->path, 0);
766         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
767         update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
768         free(new_path2);
769         free(new_path1);
770 }
771
772 static int process_renames(struct merge_options *o,
773                            struct string_list *a_renames,
774                            struct string_list *b_renames)
775 {
776         int clean_merge = 1, i, j;
777         struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
778         const struct rename *sre;
779
780         for (i = 0; i < a_renames->nr; i++) {
781                 sre = a_renames->items[i].util;
782                 string_list_insert(sre->pair->two->path, &a_by_dst)->util
783                         = sre->dst_entry;
784         }
785         for (i = 0; i < b_renames->nr; i++) {
786                 sre = b_renames->items[i].util;
787                 string_list_insert(sre->pair->two->path, &b_by_dst)->util
788                         = sre->dst_entry;
789         }
790
791         for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
792                 int compare;
793                 char *src;
794                 struct string_list *renames1, *renames2, *renames2Dst;
795                 struct rename *ren1 = NULL, *ren2 = NULL;
796                 const char *branch1, *branch2;
797                 const char *ren1_src, *ren1_dst;
798
799                 if (i >= a_renames->nr) {
800                         compare = 1;
801                         ren2 = b_renames->items[j++].util;
802                 } else if (j >= b_renames->nr) {
803                         compare = -1;
804                         ren1 = a_renames->items[i++].util;
805                 } else {
806                         compare = strcmp(a_renames->items[i].string,
807                                         b_renames->items[j].string);
808                         if (compare <= 0)
809                                 ren1 = a_renames->items[i++].util;
810                         if (compare >= 0)
811                                 ren2 = b_renames->items[j++].util;
812                 }
813
814                 /* TODO: refactor, so that 1/2 are not needed */
815                 if (ren1) {
816                         renames1 = a_renames;
817                         renames2 = b_renames;
818                         renames2Dst = &b_by_dst;
819                         branch1 = o->branch1;
820                         branch2 = o->branch2;
821                 } else {
822                         struct rename *tmp;
823                         renames1 = b_renames;
824                         renames2 = a_renames;
825                         renames2Dst = &a_by_dst;
826                         branch1 = o->branch2;
827                         branch2 = o->branch1;
828                         tmp = ren2;
829                         ren2 = ren1;
830                         ren1 = tmp;
831                 }
832                 src = ren1->pair->one->path;
833
834                 ren1->dst_entry->processed = 1;
835                 ren1->src_entry->processed = 1;
836
837                 if (ren1->processed)
838                         continue;
839                 ren1->processed = 1;
840
841                 ren1_src = ren1->pair->one->path;
842                 ren1_dst = ren1->pair->two->path;
843
844                 if (ren2) {
845                         const char *ren2_src = ren2->pair->one->path;
846                         const char *ren2_dst = ren2->pair->two->path;
847                         /* Renamed in 1 and renamed in 2 */
848                         if (strcmp(ren1_src, ren2_src) != 0)
849                                 die("ren1.src != ren2.src");
850                         ren2->dst_entry->processed = 1;
851                         ren2->processed = 1;
852                         if (strcmp(ren1_dst, ren2_dst) != 0) {
853                                 clean_merge = 0;
854                                 output(o, 1, "CONFLICT (rename/rename): "
855                                        "Rename \"%s\"->\"%s\" in branch \"%s\" "
856                                        "rename \"%s\"->\"%s\" in \"%s\"%s",
857                                        src, ren1_dst, branch1,
858                                        src, ren2_dst, branch2,
859                                        o->call_depth ? " (left unresolved)": "");
860                                 if (o->call_depth) {
861                                         remove_file_from_cache(src);
862                                         update_file(o, 0, ren1->pair->one->sha1,
863                                                     ren1->pair->one->mode, src);
864                                 }
865                                 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
866                         } else {
867                                 struct merge_file_info mfi;
868                                 remove_file(o, 1, ren1_src, 1);
869                                 mfi = merge_file(o,
870                                                  ren1->pair->one,
871                                                  ren1->pair->two,
872                                                  ren2->pair->two,
873                                                  branch1,
874                                                  branch2);
875                                 if (mfi.merge || !mfi.clean)
876                                         output(o, 1, "Renaming %s->%s", src, ren1_dst);
877
878                                 if (mfi.merge)
879                                         output(o, 2, "Auto-merging %s", ren1_dst);
880
881                                 if (!mfi.clean) {
882                                         output(o, 1, "CONFLICT (content): merge conflict in %s",
883                                                ren1_dst);
884                                         clean_merge = 0;
885
886                                         if (!o->call_depth)
887                                                 update_stages(ren1_dst,
888                                                               ren1->pair->one,
889                                                               ren1->pair->two,
890                                                               ren2->pair->two,
891                                                               1 /* clear */);
892                                 }
893                                 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
894                         }
895                 } else {
896                         /* Renamed in 1, maybe changed in 2 */
897                         struct string_list_item *item;
898                         /* we only use sha1 and mode of these */
899                         struct diff_filespec src_other, dst_other;
900                         int try_merge, stage = a_renames == renames1 ? 3: 2;
901
902                         remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
903
904                         hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
905                         src_other.mode = ren1->src_entry->stages[stage].mode;
906                         hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
907                         dst_other.mode = ren1->dst_entry->stages[stage].mode;
908
909                         try_merge = 0;
910
911                         if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
912                                 clean_merge = 0;
913                                 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
914                                        " directory %s added in %s",
915                                        ren1_src, ren1_dst, branch1,
916                                        ren1_dst, branch2);
917                                 conflict_rename_dir(o, ren1, branch1);
918                         } else if (sha_eq(src_other.sha1, null_sha1)) {
919                                 clean_merge = 0;
920                                 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
921                                        "and deleted in %s",
922                                        ren1_src, ren1_dst, branch1,
923                                        branch2);
924                                 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
925                         } else if (!sha_eq(dst_other.sha1, null_sha1)) {
926                                 const char *new_path;
927                                 clean_merge = 0;
928                                 try_merge = 1;
929                                 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
930                                        "%s added in %s",
931                                        ren1_src, ren1_dst, branch1,
932                                        ren1_dst, branch2);
933                                 new_path = unique_path(o, ren1_dst, branch2);
934                                 output(o, 1, "Adding as %s instead", new_path);
935                                 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
936                         } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
937                                 ren2 = item->util;
938                                 clean_merge = 0;
939                                 ren2->processed = 1;
940                                 output(o, 1, "CONFLICT (rename/rename): "
941                                        "Rename %s->%s in %s. "
942                                        "Rename %s->%s in %s",
943                                        ren1_src, ren1_dst, branch1,
944                                        ren2->pair->one->path, ren2->pair->two->path, branch2);
945                                 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
946                         } else
947                                 try_merge = 1;
948
949                         if (try_merge) {
950                                 struct diff_filespec *one, *a, *b;
951                                 struct merge_file_info mfi;
952                                 src_other.path = (char *)ren1_src;
953
954                                 one = ren1->pair->one;
955                                 if (a_renames == renames1) {
956                                         a = ren1->pair->two;
957                                         b = &src_other;
958                                 } else {
959                                         b = ren1->pair->two;
960                                         a = &src_other;
961                                 }
962                                 mfi = merge_file(o, one, a, b,
963                                                 o->branch1, o->branch2);
964
965                                 if (mfi.clean &&
966                                     sha_eq(mfi.sha, ren1->pair->two->sha1) &&
967                                     mfi.mode == ren1->pair->two->mode)
968                                         /*
969                                          * This messaged is part of
970                                          * t6022 test. If you change
971                                          * it update the test too.
972                                          */
973                                         output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
974                                 else {
975                                         if (mfi.merge || !mfi.clean)
976                                                 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
977                                         if (mfi.merge)
978                                                 output(o, 2, "Auto-merging %s", ren1_dst);
979                                         if (!mfi.clean) {
980                                                 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
981                                                        ren1_dst);
982                                                 clean_merge = 0;
983
984                                                 if (!o->call_depth)
985                                                         update_stages(ren1_dst,
986                                                                       one, a, b, 1);
987                                         }
988                                         update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
989                                 }
990                         }
991                 }
992         }
993         string_list_clear(&a_by_dst, 0);
994         string_list_clear(&b_by_dst, 0);
995
996         return clean_merge;
997 }
998
999 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1000 {
1001         return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1002 }
1003
1004 /* Per entry merge function */
1005 static int process_entry(struct merge_options *o,
1006                          const char *path, struct stage_data *entry)
1007 {
1008         /*
1009         printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1010         print_index_entry("\tpath: ", entry);
1011         */
1012         int clean_merge = 1;
1013         unsigned o_mode = entry->stages[1].mode;
1014         unsigned a_mode = entry->stages[2].mode;
1015         unsigned b_mode = entry->stages[3].mode;
1016         unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1017         unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1018         unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1019
1020         if (o_sha && (!a_sha || !b_sha)) {
1021                 /* Case A: Deleted in one */
1022                 if ((!a_sha && !b_sha) ||
1023                     (sha_eq(a_sha, o_sha) && !b_sha) ||
1024                     (!a_sha && sha_eq(b_sha, o_sha))) {
1025                         /* Deleted in both or deleted in one and
1026                          * unchanged in the other */
1027                         if (a_sha)
1028                                 output(o, 2, "Removing %s", path);
1029                         /* do not touch working file if it did not exist */
1030                         remove_file(o, 1, path, !a_sha);
1031                 } else {
1032                         /* Deleted in one and changed in the other */
1033                         clean_merge = 0;
1034                         if (!a_sha) {
1035                                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1036                                        "and modified in %s. Version %s of %s left in tree.",
1037                                        path, o->branch1,
1038                                        o->branch2, o->branch2, path);
1039                                 update_file(o, 0, b_sha, b_mode, path);
1040                         } else {
1041                                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1042                                        "and modified in %s. Version %s of %s left in tree.",
1043                                        path, o->branch2,
1044                                        o->branch1, o->branch1, path);
1045                                 update_file(o, 0, a_sha, a_mode, path);
1046                         }
1047                 }
1048
1049         } else if ((!o_sha && a_sha && !b_sha) ||
1050                    (!o_sha && !a_sha && b_sha)) {
1051                 /* Case B: Added in one. */
1052                 const char *add_branch;
1053                 const char *other_branch;
1054                 unsigned mode;
1055                 const unsigned char *sha;
1056                 const char *conf;
1057
1058                 if (a_sha) {
1059                         add_branch = o->branch1;
1060                         other_branch = o->branch2;
1061                         mode = a_mode;
1062                         sha = a_sha;
1063                         conf = "file/directory";
1064                 } else {
1065                         add_branch = o->branch2;
1066                         other_branch = o->branch1;
1067                         mode = b_mode;
1068                         sha = b_sha;
1069                         conf = "directory/file";
1070                 }
1071                 if (string_list_has_string(&o->current_directory_set, path)) {
1072                         const char *new_path = unique_path(o, path, add_branch);
1073                         clean_merge = 0;
1074                         output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1075                                "Adding %s as %s",
1076                                conf, path, other_branch, path, new_path);
1077                         remove_file(o, 0, path, 0);
1078                         update_file(o, 0, sha, mode, new_path);
1079                 } else {
1080                         output(o, 2, "Adding %s", path);
1081                         update_file(o, 1, sha, mode, path);
1082                 }
1083         } else if (a_sha && b_sha) {
1084                 /* Case C: Added in both (check for same permissions) and */
1085                 /* case D: Modified in both, but differently. */
1086                 const char *reason = "content";
1087                 struct merge_file_info mfi;
1088                 struct diff_filespec one, a, b;
1089
1090                 if (!o_sha) {
1091                         reason = "add/add";
1092                         o_sha = (unsigned char *)null_sha1;
1093                 }
1094                 output(o, 2, "Auto-merging %s", path);
1095                 one.path = a.path = b.path = (char *)path;
1096                 hashcpy(one.sha1, o_sha);
1097                 one.mode = o_mode;
1098                 hashcpy(a.sha1, a_sha);
1099                 a.mode = a_mode;
1100                 hashcpy(b.sha1, b_sha);
1101                 b.mode = b_mode;
1102
1103                 mfi = merge_file(o, &one, &a, &b,
1104                                  o->branch1, o->branch2);
1105
1106                 clean_merge = mfi.clean;
1107                 if (mfi.clean)
1108                         update_file(o, 1, mfi.sha, mfi.mode, path);
1109                 else if (S_ISGITLINK(mfi.mode))
1110                         output(o, 1, "CONFLICT (submodule): Merge conflict in %s "
1111                                "- needs %s", path, sha1_to_hex(b.sha1));
1112                 else {
1113                         output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1114                                         reason, path);
1115
1116                         if (o->call_depth)
1117                                 update_file(o, 0, mfi.sha, mfi.mode, path);
1118                         else
1119                                 update_file_flags(o, mfi.sha, mfi.mode, path,
1120                                               0 /* update_cache */, 1 /* update_working_directory */);
1121                 }
1122         } else if (!o_sha && !a_sha && !b_sha) {
1123                 /*
1124                  * this entry was deleted altogether. a_mode == 0 means
1125                  * we had that path and want to actively remove it.
1126                  */
1127                 remove_file(o, 1, path, !a_mode);
1128         } else
1129                 die("Fatal merge failure, shouldn't happen.");
1130
1131         return clean_merge;
1132 }
1133
1134 int merge_trees(struct merge_options *o,
1135                 struct tree *head,
1136                 struct tree *merge,
1137                 struct tree *common,
1138                 struct tree **result)
1139 {
1140         int code, clean;
1141
1142         if (o->subtree_merge) {
1143                 merge = shift_tree_object(head, merge);
1144                 common = shift_tree_object(head, common);
1145         }
1146
1147         if (sha_eq(common->object.sha1, merge->object.sha1)) {
1148                 output(o, 0, "Already uptodate!");
1149                 *result = head;
1150                 return 1;
1151         }
1152
1153         code = git_merge_trees(o->call_depth, common, head, merge);
1154
1155         if (code != 0)
1156                 die("merging of trees %s and %s failed",
1157                     sha1_to_hex(head->object.sha1),
1158                     sha1_to_hex(merge->object.sha1));
1159
1160         if (unmerged_cache()) {
1161                 struct string_list *entries, *re_head, *re_merge;
1162                 int i;
1163                 string_list_clear(&o->current_file_set, 1);
1164                 string_list_clear(&o->current_directory_set, 1);
1165                 get_files_dirs(o, head);
1166                 get_files_dirs(o, merge);
1167
1168                 entries = get_unmerged();
1169                 re_head  = get_renames(o, head, common, head, merge, entries);
1170                 re_merge = get_renames(o, merge, common, head, merge, entries);
1171                 clean = process_renames(o, re_head, re_merge);
1172                 for (i = 0; i < entries->nr; i++) {
1173                         const char *path = entries->items[i].string;
1174                         struct stage_data *e = entries->items[i].util;
1175                         if (!e->processed
1176                                 && !process_entry(o, path, e))
1177                                 clean = 0;
1178                 }
1179
1180                 string_list_clear(re_merge, 0);
1181                 string_list_clear(re_head, 0);
1182                 string_list_clear(entries, 1);
1183
1184         }
1185         else
1186                 clean = 1;
1187
1188         if (o->call_depth)
1189                 *result = write_tree_from_memory(o);
1190
1191         return clean;
1192 }
1193
1194 static struct commit_list *reverse_commit_list(struct commit_list *list)
1195 {
1196         struct commit_list *next = NULL, *current, *backup;
1197         for (current = list; current; current = backup) {
1198                 backup = current->next;
1199                 current->next = next;
1200                 next = current;
1201         }
1202         return next;
1203 }
1204
1205 /*
1206  * Merge the commits h1 and h2, return the resulting virtual
1207  * commit object and a flag indicating the cleanness of the merge.
1208  */
1209 int merge_recursive(struct merge_options *o,
1210                     struct commit *h1,
1211                     struct commit *h2,
1212                     struct commit_list *ca,
1213                     struct commit **result)
1214 {
1215         struct commit_list *iter;
1216         struct commit *merged_common_ancestors;
1217         struct tree *mrtree = mrtree;
1218         int clean;
1219
1220         if (show(o, 4)) {
1221                 output(o, 4, "Merging:");
1222                 output_commit_title(o, h1);
1223                 output_commit_title(o, h2);
1224         }
1225
1226         if (!ca) {
1227                 ca = get_merge_bases(h1, h2, 1);
1228                 ca = reverse_commit_list(ca);
1229         }
1230
1231         if (show(o, 5)) {
1232                 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1233                 for (iter = ca; iter; iter = iter->next)
1234                         output_commit_title(o, iter->item);
1235         }
1236
1237         merged_common_ancestors = pop_commit(&ca);
1238         if (merged_common_ancestors == NULL) {
1239                 /* if there is no common ancestor, make an empty tree */
1240                 struct tree *tree = xcalloc(1, sizeof(struct tree));
1241
1242                 tree->object.parsed = 1;
1243                 tree->object.type = OBJ_TREE;
1244                 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1245                 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1246         }
1247
1248         for (iter = ca; iter; iter = iter->next) {
1249                 const char *saved_b1, *saved_b2;
1250                 o->call_depth++;
1251                 /*
1252                  * When the merge fails, the result contains files
1253                  * with conflict markers. The cleanness flag is
1254                  * ignored, it was never actually used, as result of
1255                  * merge_trees has always overwritten it: the committed
1256                  * "conflicts" were already resolved.
1257                  */
1258                 discard_cache();
1259                 saved_b1 = o->branch1;
1260                 saved_b2 = o->branch2;
1261                 o->branch1 = "Temporary merge branch 1";
1262                 o->branch2 = "Temporary merge branch 2";
1263                 merge_recursive(o, merged_common_ancestors, iter->item,
1264                                 NULL, &merged_common_ancestors);
1265                 o->branch1 = saved_b1;
1266                 o->branch2 = saved_b2;
1267                 o->call_depth--;
1268
1269                 if (!merged_common_ancestors)
1270                         die("merge returned no commit");
1271         }
1272
1273         discard_cache();
1274         if (!o->call_depth)
1275                 read_cache();
1276
1277         clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1278                             &mrtree);
1279
1280         if (o->call_depth) {
1281                 *result = make_virtual_commit(mrtree, "merged tree");
1282                 commit_list_insert(h1, &(*result)->parents);
1283                 commit_list_insert(h2, &(*result)->parents->next);
1284         }
1285         flush_output(o);
1286         return clean;
1287 }
1288
1289 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1290 {
1291         struct object *object;
1292
1293         object = deref_tag(parse_object(sha1), name, strlen(name));
1294         if (!object)
1295                 return NULL;
1296         if (object->type == OBJ_TREE)
1297                 return make_virtual_commit((struct tree*)object, name);
1298         if (object->type != OBJ_COMMIT)
1299                 return NULL;
1300         if (parse_commit((struct commit *)object))
1301                 return NULL;
1302         return (struct commit *)object;
1303 }
1304
1305 int merge_recursive_generic(struct merge_options *o,
1306                             const unsigned char *head,
1307                             const unsigned char *merge,
1308                             int num_base_list,
1309                             const unsigned char **base_list,
1310                             struct commit **result)
1311 {
1312         int clean, index_fd;
1313         struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1314         struct commit *head_commit = get_ref(head, o->branch1);
1315         struct commit *next_commit = get_ref(merge, o->branch2);
1316         struct commit_list *ca = NULL;
1317
1318         if (base_list) {
1319                 int i;
1320                 for (i = 0; i < num_base_list; ++i) {
1321                         struct commit *base;
1322                         if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1323                                 return error("Could not parse object '%s'",
1324                                         sha1_to_hex(base_list[i]));
1325                         commit_list_insert(base, &ca);
1326                 }
1327         }
1328
1329         index_fd = hold_locked_index(lock, 1);
1330         clean = merge_recursive(o, head_commit, next_commit, ca,
1331                         result);
1332         if (active_cache_changed &&
1333                         (write_cache(index_fd, active_cache, active_nr) ||
1334                          commit_locked_index(lock)))
1335                 return error("Unable to write index.");
1336
1337         return clean ? 0 : 1;
1338 }
1339
1340 static int merge_recursive_config(const char *var, const char *value, void *cb)
1341 {
1342         struct merge_options *o = cb;
1343         if (!strcasecmp(var, "merge.verbosity")) {
1344                 o->verbosity = git_config_int(var, value);
1345                 return 0;
1346         }
1347         if (!strcasecmp(var, "diff.renamelimit")) {
1348                 o->diff_rename_limit = git_config_int(var, value);
1349                 return 0;
1350         }
1351         if (!strcasecmp(var, "merge.renamelimit")) {
1352                 o->merge_rename_limit = git_config_int(var, value);
1353                 return 0;
1354         }
1355         return git_default_config(var, value, cb);
1356 }
1357
1358 void init_merge_options(struct merge_options *o)
1359 {
1360         memset(o, 0, sizeof(struct merge_options));
1361         o->verbosity = 2;
1362         o->buffer_output = 1;
1363         o->diff_rename_limit = -1;
1364         o->merge_rename_limit = -1;
1365         git_config(merge_recursive_config, o);
1366         if (getenv("GIT_MERGE_VERBOSITY"))
1367                 o->verbosity =
1368                         strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1369         if (o->verbosity >= 5)
1370                 o->buffer_output = 0;
1371         strbuf_init(&o->obuf, 0);
1372         memset(&o->current_file_set, 0, sizeof(struct string_list));
1373         o->current_file_set.strdup_strings = 1;
1374         memset(&o->current_directory_set, 0, sizeof(struct string_list));
1375         o->current_directory_set.strdup_strings = 1;
1376 }