Code

user-manual: Document that "git merge" doesn't like uncommited changes.
[git.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 "advice.h"
7 #include "cache.h"
8 #include "cache-tree.h"
9 #include "commit.h"
10 #include "blob.h"
11 #include "builtin.h"
12 #include "tree-walk.h"
13 #include "diff.h"
14 #include "diffcore.h"
15 #include "tag.h"
16 #include "unpack-trees.h"
17 #include "string-list.h"
18 #include "xdiff-interface.h"
19 #include "ll-merge.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
22 #include "dir.h"
24 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
25 {
26         unsigned char shifted[20];
28         /*
29          * NEEDSWORK: this limits the recursion depth to hardcoded
30          * value '2' to avoid excessive overhead.
31          */
32         shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
33         if (!hashcmp(two->object.sha1, shifted))
34                 return two;
35         return lookup_tree(shifted);
36 }
38 /*
39  * A virtual commit has (const char *)commit->util set to the name.
40  */
42 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
43 {
44         struct commit *commit = xcalloc(1, sizeof(struct commit));
45         commit->tree = tree;
46         commit->util = (void*)comment;
47         /* avoid warnings */
48         commit->object.parsed = 1;
49         return commit;
50 }
52 /*
53  * Since we use get_tree_entry(), which does not put the read object into
54  * the object pool, we cannot rely on a == b.
55  */
56 static int sha_eq(const unsigned char *a, const unsigned char *b)
57 {
58         if (!a && !b)
59                 return 2;
60         return a && b && hashcmp(a, b) == 0;
61 }
63 /*
64  * Since we want to write the index eventually, we cannot reuse the index
65  * for these (temporary) data.
66  */
67 struct stage_data
68 {
69         struct
70         {
71                 unsigned mode;
72                 unsigned char sha[20];
73         } stages[4];
74         unsigned processed:1;
75 };
77 static int show(struct merge_options *o, int v)
78 {
79         return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
80 }
82 static void flush_output(struct merge_options *o)
83 {
84         if (o->obuf.len) {
85                 fputs(o->obuf.buf, stdout);
86                 strbuf_reset(&o->obuf);
87         }
88 }
90 static void output(struct merge_options *o, int v, const char *fmt, ...)
91 {
92         int len;
93         va_list ap;
95         if (!show(o, v))
96                 return;
98         strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
99         memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
100         strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
102         va_start(ap, fmt);
103         len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
104         va_end(ap);
106         if (len < 0)
107                 len = 0;
108         if (len >= strbuf_avail(&o->obuf)) {
109                 strbuf_grow(&o->obuf, len + 2);
110                 va_start(ap, fmt);
111                 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
112                 va_end(ap);
113                 if (len >= strbuf_avail(&o->obuf)) {
114                         die("this should not happen, your snprintf is broken");
115                 }
116         }
117         strbuf_setlen(&o->obuf, o->obuf.len + len);
118         strbuf_add(&o->obuf, "\n", 1);
119         if (!o->buffer_output)
120                 flush_output(o);
123 static void output_commit_title(struct merge_options *o, struct commit *commit)
125         int i;
126         flush_output(o);
127         for (i = o->call_depth; i--;)
128                 fputs("  ", stdout);
129         if (commit->util)
130                 printf("virtual %s\n", (char *)commit->util);
131         else {
132                 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
133                 if (parse_commit(commit) != 0)
134                         printf("(bad commit)\n");
135                 else {
136                         const char *s;
137                         int len;
138                         for (s = commit->buffer; *s; s++)
139                                 if (*s == '\n' && s[1] == '\n') {
140                                         s += 2;
141                                         break;
142                                 }
143                         for (len = 0; s[len] && '\n' != s[len]; len++)
144                                 ; /* do nothing */
145                         printf("%.*s\n", len, s);
146                 }
147         }
150 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
151                 const char *path, int stage, int refresh, int options)
153         struct cache_entry *ce;
154         ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
155         if (!ce)
156                 return error("addinfo_cache failed for path '%s'", path);
157         return add_cache_entry(ce, options);
160 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
162         parse_tree(tree);
163         init_tree_desc(desc, tree->buffer, tree->size);
166 static int git_merge_trees(int index_only,
167                            struct tree *common,
168                            struct tree *head,
169                            struct tree *merge)
171         int rc;
172         struct tree_desc t[3];
173         struct unpack_trees_options opts;
174         struct unpack_trees_error_msgs msgs = {
175                 /* would_overwrite */
176                 "Your local changes to '%s' would be overwritten by merge.  Aborting.",
177                 /* not_uptodate_file */
178                 "Your local changes to '%s' would be overwritten by merge.  Aborting.",
179                 /* not_uptodate_dir */
180                 "Updating '%s' would lose untracked files in it.  Aborting.",
181                 /* would_lose_untracked */
182                 "Untracked working tree file '%s' would be %s by merge.  Aborting",
183                 /* bind_overlap -- will not happen here */
184                 NULL,
185         };
186         if (advice_commit_before_merge) {
187                 msgs.would_overwrite = msgs.not_uptodate_file =
188                         "Your local changes to '%s' would be overwritten by merge.  Aborting.\n"
189                         "Please, commit your changes or stash them before you can merge.";
190         }
192         memset(&opts, 0, sizeof(opts));
193         if (index_only)
194                 opts.index_only = 1;
195         else
196                 opts.update = 1;
197         opts.merge = 1;
198         opts.head_idx = 2;
199         opts.fn = threeway_merge;
200         opts.src_index = &the_index;
201         opts.dst_index = &the_index;
202         opts.msgs = msgs;
204         init_tree_desc_from_tree(t+0, common);
205         init_tree_desc_from_tree(t+1, head);
206         init_tree_desc_from_tree(t+2, merge);
208         rc = unpack_trees(3, t, &opts);
209         cache_tree_free(&active_cache_tree);
210         return rc;
213 struct tree *write_tree_from_memory(struct merge_options *o)
215         struct tree *result = NULL;
217         if (unmerged_cache()) {
218                 int i;
219                 output(o, 0, "There are unmerged index entries:");
220                 for (i = 0; i < active_nr; i++) {
221                         struct cache_entry *ce = active_cache[i];
222                         if (ce_stage(ce))
223                                 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
224                 }
225                 return NULL;
226         }
228         if (!active_cache_tree)
229                 active_cache_tree = cache_tree();
231         if (!cache_tree_fully_valid(active_cache_tree) &&
232             cache_tree_update(active_cache_tree,
233                               active_cache, active_nr, 0, 0) < 0)
234                 die("error building trees");
236         result = lookup_tree(active_cache_tree->sha1);
238         return result;
241 static int save_files_dirs(const unsigned char *sha1,
242                 const char *base, int baselen, const char *path,
243                 unsigned int mode, int stage, void *context)
245         int len = strlen(path);
246         char *newpath = xmalloc(baselen + len + 1);
247         struct merge_options *o = context;
249         memcpy(newpath, base, baselen);
250         memcpy(newpath + baselen, path, len);
251         newpath[baselen + len] = '\0';
253         if (S_ISDIR(mode))
254                 string_list_insert(newpath, &o->current_directory_set);
255         else
256                 string_list_insert(newpath, &o->current_file_set);
257         free(newpath);
259         return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
262 static int get_files_dirs(struct merge_options *o, struct tree *tree)
264         int n;
265         if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
266                 return 0;
267         n = o->current_file_set.nr + o->current_directory_set.nr;
268         return n;
271 /*
272  * Returns an index_entry instance which doesn't have to correspond to
273  * a real cache entry in Git's index.
274  */
275 static struct stage_data *insert_stage_data(const char *path,
276                 struct tree *o, struct tree *a, struct tree *b,
277                 struct string_list *entries)
279         struct string_list_item *item;
280         struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
281         get_tree_entry(o->object.sha1, path,
282                         e->stages[1].sha, &e->stages[1].mode);
283         get_tree_entry(a->object.sha1, path,
284                         e->stages[2].sha, &e->stages[2].mode);
285         get_tree_entry(b->object.sha1, path,
286                         e->stages[3].sha, &e->stages[3].mode);
287         item = string_list_insert(path, entries);
288         item->util = e;
289         return e;
292 /*
293  * Create a dictionary mapping file names to stage_data objects. The
294  * dictionary contains one entry for every path with a non-zero stage entry.
295  */
296 static struct string_list *get_unmerged(void)
298         struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
299         int i;
301         unmerged->strdup_strings = 1;
303         for (i = 0; i < active_nr; i++) {
304                 struct string_list_item *item;
305                 struct stage_data *e;
306                 struct cache_entry *ce = active_cache[i];
307                 if (!ce_stage(ce))
308                         continue;
310                 item = string_list_lookup(ce->name, unmerged);
311                 if (!item) {
312                         item = string_list_insert(ce->name, unmerged);
313                         item->util = xcalloc(1, sizeof(struct stage_data));
314                 }
315                 e = item->util;
316                 e->stages[ce_stage(ce)].mode = ce->ce_mode;
317                 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
318         }
320         return unmerged;
323 struct rename
325         struct diff_filepair *pair;
326         struct stage_data *src_entry;
327         struct stage_data *dst_entry;
328         unsigned processed:1;
329 };
331 /*
332  * Get information of all renames which occurred between 'o_tree' and
333  * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
334  * 'b_tree') to be able to associate the correct cache entries with
335  * the rename information. 'tree' is always equal to either a_tree or b_tree.
336  */
337 static struct string_list *get_renames(struct merge_options *o,
338                                        struct tree *tree,
339                                        struct tree *o_tree,
340                                        struct tree *a_tree,
341                                        struct tree *b_tree,
342                                        struct string_list *entries)
344         int i;
345         struct string_list *renames;
346         struct diff_options opts;
348         renames = xcalloc(1, sizeof(struct string_list));
349         diff_setup(&opts);
350         DIFF_OPT_SET(&opts, RECURSIVE);
351         opts.detect_rename = DIFF_DETECT_RENAME;
352         opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
353                             o->diff_rename_limit >= 0 ? o->diff_rename_limit :
354                             500;
355         opts.warn_on_too_large_rename = 1;
356         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
357         if (diff_setup_done(&opts) < 0)
358                 die("diff setup failed");
359         diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
360         diffcore_std(&opts);
361         for (i = 0; i < diff_queued_diff.nr; ++i) {
362                 struct string_list_item *item;
363                 struct rename *re;
364                 struct diff_filepair *pair = diff_queued_diff.queue[i];
365                 if (pair->status != 'R') {
366                         diff_free_filepair(pair);
367                         continue;
368                 }
369                 re = xmalloc(sizeof(*re));
370                 re->processed = 0;
371                 re->pair = pair;
372                 item = string_list_lookup(re->pair->one->path, entries);
373                 if (!item)
374                         re->src_entry = insert_stage_data(re->pair->one->path,
375                                         o_tree, a_tree, b_tree, entries);
376                 else
377                         re->src_entry = item->util;
379                 item = string_list_lookup(re->pair->two->path, entries);
380                 if (!item)
381                         re->dst_entry = insert_stage_data(re->pair->two->path,
382                                         o_tree, a_tree, b_tree, entries);
383                 else
384                         re->dst_entry = item->util;
385                 item = string_list_insert(pair->one->path, renames);
386                 item->util = re;
387         }
388         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
389         diff_queued_diff.nr = 0;
390         diff_flush(&opts);
391         return renames;
394 static int update_stages(const char *path, struct diff_filespec *o,
395                          struct diff_filespec *a, struct diff_filespec *b,
396                          int clear)
398         int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
399         if (clear)
400                 if (remove_file_from_cache(path))
401                         return -1;
402         if (o)
403                 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
404                         return -1;
405         if (a)
406                 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
407                         return -1;
408         if (b)
409                 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
410                         return -1;
411         return 0;
414 static int remove_file(struct merge_options *o, int clean,
415                        const char *path, int no_wd)
417         int update_cache = o->call_depth || clean;
418         int update_working_directory = !o->call_depth && !no_wd;
420         if (update_cache) {
421                 if (remove_file_from_cache(path))
422                         return -1;
423         }
424         if (update_working_directory) {
425                 if (remove_path(path) && errno != ENOENT)
426                         return -1;
427         }
428         return 0;
431 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
433         char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
434         int suffix = 0;
435         struct stat st;
436         char *p = newpath + strlen(path);
437         strcpy(newpath, path);
438         *(p++) = '~';
439         strcpy(p, branch);
440         for (; *p; ++p)
441                 if ('/' == *p)
442                         *p = '_';
443         while (string_list_has_string(&o->current_file_set, newpath) ||
444                string_list_has_string(&o->current_directory_set, newpath) ||
445                lstat(newpath, &st) == 0)
446                 sprintf(p, "_%d", suffix++);
448         string_list_insert(newpath, &o->current_file_set);
449         return newpath;
452 static void flush_buffer(int fd, const char *buf, unsigned long size)
454         while (size > 0) {
455                 long ret = write_in_full(fd, buf, size);
456                 if (ret < 0) {
457                         /* Ignore epipe */
458                         if (errno == EPIPE)
459                                 break;
460                         die_errno("merge-recursive");
461                 } else if (!ret) {
462                         die("merge-recursive: disk full?");
463                 }
464                 size -= ret;
465                 buf += ret;
466         }
469 static int would_lose_untracked(const char *path)
471         int pos = cache_name_pos(path, strlen(path));
473         if (pos < 0)
474                 pos = -1 - pos;
475         while (pos < active_nr &&
476                !strcmp(path, active_cache[pos]->name)) {
477                 /*
478                  * If stage #0, it is definitely tracked.
479                  * If it has stage #2 then it was tracked
480                  * before this merge started.  All other
481                  * cases the path was not tracked.
482                  */
483                 switch (ce_stage(active_cache[pos])) {
484                 case 0:
485                 case 2:
486                         return 0;
487                 }
488                 pos++;
489         }
490         return file_exists(path);
493 static int make_room_for_path(const char *path)
495         int status;
496         const char *msg = "failed to create path '%s'%s";
498         status = safe_create_leading_directories_const(path);
499         if (status) {
500                 if (status == -3) {
501                         /* something else exists */
502                         error(msg, path, ": perhaps a D/F conflict?");
503                         return -1;
504                 }
505                 die(msg, path, "");
506         }
508         /*
509          * Do not unlink a file in the work tree if we are not
510          * tracking it.
511          */
512         if (would_lose_untracked(path))
513                 return error("refusing to lose untracked file at '%s'",
514                              path);
516         /* Successful unlink is good.. */
517         if (!unlink(path))
518                 return 0;
519         /* .. and so is no existing file */
520         if (errno == ENOENT)
521                 return 0;
522         /* .. but not some other error (who really cares what?) */
523         return error(msg, path, ": perhaps a D/F conflict?");
526 static void update_file_flags(struct merge_options *o,
527                               const unsigned char *sha,
528                               unsigned mode,
529                               const char *path,
530                               int update_cache,
531                               int update_wd)
533         if (o->call_depth)
534                 update_wd = 0;
536         if (update_wd) {
537                 enum object_type type;
538                 void *buf;
539                 unsigned long size;
541                 if (S_ISGITLINK(mode))
542                         /*
543                          * We may later decide to recursively descend into
544                          * the submodule directory and update its index
545                          * and/or work tree, but we do not do that now.
546                          */
547                         goto update_index;
549                 buf = read_sha1_file(sha, &type, &size);
550                 if (!buf)
551                         die("cannot read object %s '%s'", sha1_to_hex(sha), path);
552                 if (type != OBJ_BLOB)
553                         die("blob expected for %s '%s'", sha1_to_hex(sha), path);
554                 if (S_ISREG(mode)) {
555                         struct strbuf strbuf = STRBUF_INIT;
556                         if (convert_to_working_tree(path, buf, size, &strbuf)) {
557                                 free(buf);
558                                 size = strbuf.len;
559                                 buf = strbuf_detach(&strbuf, NULL);
560                         }
561                 }
563                 if (make_room_for_path(path) < 0) {
564                         update_wd = 0;
565                         free(buf);
566                         goto update_index;
567                 }
568                 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
569                         int fd;
570                         if (mode & 0100)
571                                 mode = 0777;
572                         else
573                                 mode = 0666;
574                         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
575                         if (fd < 0)
576                                 die_errno("failed to open '%s'", path);
577                         flush_buffer(fd, buf, size);
578                         close(fd);
579                 } else if (S_ISLNK(mode)) {
580                         char *lnk = xmemdupz(buf, size);
581                         safe_create_leading_directories_const(path);
582                         unlink(path);
583                         if (symlink(lnk, path))
584                                 die_errno("failed to symlink '%s'", path);
585                         free(lnk);
586                 } else
587                         die("do not know what to do with %06o %s '%s'",
588                             mode, sha1_to_hex(sha), path);
589                 free(buf);
590         }
591  update_index:
592         if (update_cache)
593                 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
596 static void update_file(struct merge_options *o,
597                         int clean,
598                         const unsigned char *sha,
599                         unsigned mode,
600                         const char *path)
602         update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
605 /* Low level file merging, update and removal */
607 struct merge_file_info
609         unsigned char sha[20];
610         unsigned mode;
611         unsigned clean:1,
612                  merge:1;
613 };
615 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
617         unsigned long size;
618         enum object_type type;
620         if (!hashcmp(sha1, null_sha1)) {
621                 mm->ptr = xstrdup("");
622                 mm->size = 0;
623                 return;
624         }
626         mm->ptr = read_sha1_file(sha1, &type, &size);
627         if (!mm->ptr || type != OBJ_BLOB)
628                 die("unable to read blob object %s", sha1_to_hex(sha1));
629         mm->size = size;
632 static int merge_3way(struct merge_options *o,
633                       mmbuffer_t *result_buf,
634                       struct diff_filespec *one,
635                       struct diff_filespec *a,
636                       struct diff_filespec *b,
637                       const char *branch1,
638                       const char *branch2)
640         mmfile_t orig, src1, src2;
641         char *name1, *name2;
642         int merge_status;
644         if (strcmp(a->path, b->path)) {
645                 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
646                 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
647         } else {
648                 name1 = xstrdup(mkpath("%s", branch1));
649                 name2 = xstrdup(mkpath("%s", branch2));
650         }
652         fill_mm(one->sha1, &orig);
653         fill_mm(a->sha1, &src1);
654         fill_mm(b->sha1, &src2);
656         merge_status = ll_merge(result_buf, a->path, &orig,
657                                 &src1, name1, &src2, name2,
658                                 o->call_depth);
660         free(name1);
661         free(name2);
662         free(orig.ptr);
663         free(src1.ptr);
664         free(src2.ptr);
665         return merge_status;
668 static struct merge_file_info merge_file(struct merge_options *o,
669                                          struct diff_filespec *one,
670                                          struct diff_filespec *a,
671                                          struct diff_filespec *b,
672                                          const char *branch1,
673                                          const char *branch2)
675         struct merge_file_info result;
676         result.merge = 0;
677         result.clean = 1;
679         if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
680                 result.clean = 0;
681                 if (S_ISREG(a->mode)) {
682                         result.mode = a->mode;
683                         hashcpy(result.sha, a->sha1);
684                 } else {
685                         result.mode = b->mode;
686                         hashcpy(result.sha, b->sha1);
687                 }
688         } else {
689                 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
690                         result.merge = 1;
692                 /*
693                  * Merge modes
694                  */
695                 if (a->mode == b->mode || a->mode == one->mode)
696                         result.mode = b->mode;
697                 else {
698                         result.mode = a->mode;
699                         if (b->mode != one->mode) {
700                                 result.clean = 0;
701                                 result.merge = 1;
702                         }
703                 }
705                 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
706                         hashcpy(result.sha, b->sha1);
707                 else if (sha_eq(b->sha1, one->sha1))
708                         hashcpy(result.sha, a->sha1);
709                 else if (S_ISREG(a->mode)) {
710                         mmbuffer_t result_buf;
711                         int merge_status;
713                         merge_status = merge_3way(o, &result_buf, one, a, b,
714                                                   branch1, branch2);
716                         if ((merge_status < 0) || !result_buf.ptr)
717                                 die("Failed to execute internal merge");
719                         if (write_sha1_file(result_buf.ptr, result_buf.size,
720                                             blob_type, result.sha))
721                                 die("Unable to add %s to database",
722                                     a->path);
724                         free(result_buf.ptr);
725                         result.clean = (merge_status == 0);
726                 } else if (S_ISGITLINK(a->mode)) {
727                         result.clean = 0;
728                         hashcpy(result.sha, a->sha1);
729                 } else if (S_ISLNK(a->mode)) {
730                         hashcpy(result.sha, a->sha1);
732                         if (!sha_eq(a->sha1, b->sha1))
733                                 result.clean = 0;
734                 } else {
735                         die("unsupported object type in the tree");
736                 }
737         }
739         return result;
742 static void conflict_rename_rename(struct merge_options *o,
743                                    struct rename *ren1,
744                                    const char *branch1,
745                                    struct rename *ren2,
746                                    const char *branch2)
748         char *del[2];
749         int delp = 0;
750         const char *ren1_dst = ren1->pair->two->path;
751         const char *ren2_dst = ren2->pair->two->path;
752         const char *dst_name1 = ren1_dst;
753         const char *dst_name2 = ren2_dst;
754         if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
755                 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
756                 output(o, 1, "%s is a directory in %s adding as %s instead",
757                        ren1_dst, branch2, dst_name1);
758                 remove_file(o, 0, ren1_dst, 0);
759         }
760         if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
761                 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
762                 output(o, 1, "%s is a directory in %s adding as %s instead",
763                        ren2_dst, branch1, dst_name2);
764                 remove_file(o, 0, ren2_dst, 0);
765         }
766         if (o->call_depth) {
767                 remove_file_from_cache(dst_name1);
768                 remove_file_from_cache(dst_name2);
769                 /*
770                  * Uncomment to leave the conflicting names in the resulting tree
771                  *
772                  * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
773                  * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
774                  */
775         } else {
776                 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
777                 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
778         }
779         while (delp--)
780                 free(del[delp]);
783 static void conflict_rename_dir(struct merge_options *o,
784                                 struct rename *ren1,
785                                 const char *branch1)
787         char *new_path = unique_path(o, ren1->pair->two->path, branch1);
788         output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
789         remove_file(o, 0, ren1->pair->two->path, 0);
790         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
791         free(new_path);
794 static void conflict_rename_rename_2(struct merge_options *o,
795                                      struct rename *ren1,
796                                      const char *branch1,
797                                      struct rename *ren2,
798                                      const char *branch2)
800         char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
801         char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
802         output(o, 1, "Renaming %s to %s and %s to %s instead",
803                ren1->pair->one->path, new_path1,
804                ren2->pair->one->path, new_path2);
805         remove_file(o, 0, ren1->pair->two->path, 0);
806         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
807         update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
808         free(new_path2);
809         free(new_path1);
812 static int process_renames(struct merge_options *o,
813                            struct string_list *a_renames,
814                            struct string_list *b_renames)
816         int clean_merge = 1, i, j;
817         struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
818         const struct rename *sre;
820         for (i = 0; i < a_renames->nr; i++) {
821                 sre = a_renames->items[i].util;
822                 string_list_insert(sre->pair->two->path, &a_by_dst)->util
823                         = sre->dst_entry;
824         }
825         for (i = 0; i < b_renames->nr; i++) {
826                 sre = b_renames->items[i].util;
827                 string_list_insert(sre->pair->two->path, &b_by_dst)->util
828                         = sre->dst_entry;
829         }
831         for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
832                 char *src;
833                 struct string_list *renames1, *renames2Dst;
834                 struct rename *ren1 = NULL, *ren2 = NULL;
835                 const char *branch1, *branch2;
836                 const char *ren1_src, *ren1_dst;
838                 if (i >= a_renames->nr) {
839                         ren2 = b_renames->items[j++].util;
840                 } else if (j >= b_renames->nr) {
841                         ren1 = a_renames->items[i++].util;
842                 } else {
843                         int compare = strcmp(a_renames->items[i].string,
844                                              b_renames->items[j].string);
845                         if (compare <= 0)
846                                 ren1 = a_renames->items[i++].util;
847                         if (compare >= 0)
848                                 ren2 = b_renames->items[j++].util;
849                 }
851                 /* TODO: refactor, so that 1/2 are not needed */
852                 if (ren1) {
853                         renames1 = a_renames;
854                         renames2Dst = &b_by_dst;
855                         branch1 = o->branch1;
856                         branch2 = o->branch2;
857                 } else {
858                         struct rename *tmp;
859                         renames1 = b_renames;
860                         renames2Dst = &a_by_dst;
861                         branch1 = o->branch2;
862                         branch2 = o->branch1;
863                         tmp = ren2;
864                         ren2 = ren1;
865                         ren1 = tmp;
866                 }
867                 src = ren1->pair->one->path;
869                 ren1->dst_entry->processed = 1;
870                 ren1->src_entry->processed = 1;
872                 if (ren1->processed)
873                         continue;
874                 ren1->processed = 1;
876                 ren1_src = ren1->pair->one->path;
877                 ren1_dst = ren1->pair->two->path;
879                 if (ren2) {
880                         const char *ren2_src = ren2->pair->one->path;
881                         const char *ren2_dst = ren2->pair->two->path;
882                         /* Renamed in 1 and renamed in 2 */
883                         if (strcmp(ren1_src, ren2_src) != 0)
884                                 die("ren1.src != ren2.src");
885                         ren2->dst_entry->processed = 1;
886                         ren2->processed = 1;
887                         if (strcmp(ren1_dst, ren2_dst) != 0) {
888                                 clean_merge = 0;
889                                 output(o, 1, "CONFLICT (rename/rename): "
890                                        "Rename \"%s\"->\"%s\" in branch \"%s\" "
891                                        "rename \"%s\"->\"%s\" in \"%s\"%s",
892                                        src, ren1_dst, branch1,
893                                        src, ren2_dst, branch2,
894                                        o->call_depth ? " (left unresolved)": "");
895                                 if (o->call_depth) {
896                                         remove_file_from_cache(src);
897                                         update_file(o, 0, ren1->pair->one->sha1,
898                                                     ren1->pair->one->mode, src);
899                                 }
900                                 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
901                         } else {
902                                 struct merge_file_info mfi;
903                                 remove_file(o, 1, ren1_src, 1);
904                                 mfi = merge_file(o,
905                                                  ren1->pair->one,
906                                                  ren1->pair->two,
907                                                  ren2->pair->two,
908                                                  branch1,
909                                                  branch2);
910                                 if (mfi.merge || !mfi.clean)
911                                         output(o, 1, "Renaming %s->%s", src, ren1_dst);
913                                 if (mfi.merge)
914                                         output(o, 2, "Auto-merging %s", ren1_dst);
916                                 if (!mfi.clean) {
917                                         output(o, 1, "CONFLICT (content): merge conflict in %s",
918                                                ren1_dst);
919                                         clean_merge = 0;
921                                         if (!o->call_depth)
922                                                 update_stages(ren1_dst,
923                                                               ren1->pair->one,
924                                                               ren1->pair->two,
925                                                               ren2->pair->two,
926                                                               1 /* clear */);
927                                 }
928                                 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
929                         }
930                 } else {
931                         /* Renamed in 1, maybe changed in 2 */
932                         struct string_list_item *item;
933                         /* we only use sha1 and mode of these */
934                         struct diff_filespec src_other, dst_other;
935                         int try_merge, stage = a_renames == renames1 ? 3: 2;
937                         remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
939                         hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
940                         src_other.mode = ren1->src_entry->stages[stage].mode;
941                         hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
942                         dst_other.mode = ren1->dst_entry->stages[stage].mode;
944                         try_merge = 0;
946                         if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
947                                 clean_merge = 0;
948                                 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
949                                        " directory %s added in %s",
950                                        ren1_src, ren1_dst, branch1,
951                                        ren1_dst, branch2);
952                                 conflict_rename_dir(o, ren1, branch1);
953                         } else if (sha_eq(src_other.sha1, null_sha1)) {
954                                 clean_merge = 0;
955                                 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
956                                        "and deleted in %s",
957                                        ren1_src, ren1_dst, branch1,
958                                        branch2);
959                                 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
960                                 if (!o->call_depth)
961                                         update_stages(ren1_dst, NULL,
962                                                         branch1 == o->branch1 ?
963                                                         ren1->pair->two : NULL,
964                                                         branch1 == o->branch1 ?
965                                                         NULL : ren1->pair->two, 1);
966                         } else if (!sha_eq(dst_other.sha1, null_sha1)) {
967                                 const char *new_path;
968                                 clean_merge = 0;
969                                 try_merge = 1;
970                                 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
971                                        "%s added in %s",
972                                        ren1_src, ren1_dst, branch1,
973                                        ren1_dst, branch2);
974                                 if (o->call_depth) {
975                                         struct merge_file_info mfi;
976                                         struct diff_filespec one, a, b;
978                                         one.path = a.path = b.path =
979                                                 (char *)ren1_dst;
980                                         hashcpy(one.sha1, null_sha1);
981                                         one.mode = 0;
982                                         hashcpy(a.sha1, ren1->pair->two->sha1);
983                                         a.mode = ren1->pair->two->mode;
984                                         hashcpy(b.sha1, dst_other.sha1);
985                                         b.mode = dst_other.mode;
986                                         mfi = merge_file(o, &one, &a, &b,
987                                                          branch1,
988                                                          branch2);
989                                         output(o, 1, "Adding merged %s", ren1_dst);
990                                         update_file(o, 0,
991                                                     mfi.sha,
992                                                     mfi.mode,
993                                                     ren1_dst);
994                                 } else {
995                                         new_path = unique_path(o, ren1_dst, branch2);
996                                         output(o, 1, "Adding as %s instead", new_path);
997                                         update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
998                                 }
999                         } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
1000                                 ren2 = item->util;
1001                                 clean_merge = 0;
1002                                 ren2->processed = 1;
1003                                 output(o, 1, "CONFLICT (rename/rename): "
1004                                        "Rename %s->%s in %s. "
1005                                        "Rename %s->%s in %s",
1006                                        ren1_src, ren1_dst, branch1,
1007                                        ren2->pair->one->path, ren2->pair->two->path, branch2);
1008                                 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
1009                         } else
1010                                 try_merge = 1;
1012                         if (try_merge) {
1013                                 struct diff_filespec *one, *a, *b;
1014                                 struct merge_file_info mfi;
1015                                 src_other.path = (char *)ren1_src;
1017                                 one = ren1->pair->one;
1018                                 if (a_renames == renames1) {
1019                                         a = ren1->pair->two;
1020                                         b = &src_other;
1021                                 } else {
1022                                         b = ren1->pair->two;
1023                                         a = &src_other;
1024                                 }
1025                                 mfi = merge_file(o, one, a, b,
1026                                                 o->branch1, o->branch2);
1028                                 if (mfi.clean &&
1029                                     sha_eq(mfi.sha, ren1->pair->two->sha1) &&
1030                                     mfi.mode == ren1->pair->two->mode)
1031                                         /*
1032                                          * This messaged is part of
1033                                          * t6022 test. If you change
1034                                          * it update the test too.
1035                                          */
1036                                         output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
1037                                 else {
1038                                         if (mfi.merge || !mfi.clean)
1039                                                 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
1040                                         if (mfi.merge)
1041                                                 output(o, 2, "Auto-merging %s", ren1_dst);
1042                                         if (!mfi.clean) {
1043                                                 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
1044                                                        ren1_dst);
1045                                                 clean_merge = 0;
1047                                                 if (!o->call_depth)
1048                                                         update_stages(ren1_dst,
1049                                                                       one, a, b, 1);
1050                                         }
1051                                         update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1052                                 }
1053                         }
1054                 }
1055         }
1056         string_list_clear(&a_by_dst, 0);
1057         string_list_clear(&b_by_dst, 0);
1059         return clean_merge;
1062 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1064         return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1067 /* Per entry merge function */
1068 static int process_entry(struct merge_options *o,
1069                          const char *path, struct stage_data *entry)
1071         /*
1072         printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1073         print_index_entry("\tpath: ", entry);
1074         */
1075         int clean_merge = 1;
1076         unsigned o_mode = entry->stages[1].mode;
1077         unsigned a_mode = entry->stages[2].mode;
1078         unsigned b_mode = entry->stages[3].mode;
1079         unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1080         unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1081         unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1083         if (o_sha && (!a_sha || !b_sha)) {
1084                 /* Case A: Deleted in one */
1085                 if ((!a_sha && !b_sha) ||
1086                     (sha_eq(a_sha, o_sha) && !b_sha) ||
1087                     (!a_sha && sha_eq(b_sha, o_sha))) {
1088                         /* Deleted in both or deleted in one and
1089                          * unchanged in the other */
1090                         if (a_sha)
1091                                 output(o, 2, "Removing %s", path);
1092                         /* do not touch working file if it did not exist */
1093                         remove_file(o, 1, path, !a_sha);
1094                 } else {
1095                         /* Deleted in one and changed in the other */
1096                         clean_merge = 0;
1097                         if (!a_sha) {
1098                                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1099                                        "and modified in %s. Version %s of %s left in tree.",
1100                                        path, o->branch1,
1101                                        o->branch2, o->branch2, path);
1102                                 update_file(o, 0, b_sha, b_mode, path);
1103                         } else {
1104                                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1105                                        "and modified in %s. Version %s of %s left in tree.",
1106                                        path, o->branch2,
1107                                        o->branch1, o->branch1, path);
1108                                 update_file(o, 0, a_sha, a_mode, path);
1109                         }
1110                 }
1112         } else if ((!o_sha && a_sha && !b_sha) ||
1113                    (!o_sha && !a_sha && b_sha)) {
1114                 /* Case B: Added in one. */
1115                 const char *add_branch;
1116                 const char *other_branch;
1117                 unsigned mode;
1118                 const unsigned char *sha;
1119                 const char *conf;
1121                 if (a_sha) {
1122                         add_branch = o->branch1;
1123                         other_branch = o->branch2;
1124                         mode = a_mode;
1125                         sha = a_sha;
1126                         conf = "file/directory";
1127                 } else {
1128                         add_branch = o->branch2;
1129                         other_branch = o->branch1;
1130                         mode = b_mode;
1131                         sha = b_sha;
1132                         conf = "directory/file";
1133                 }
1134                 if (string_list_has_string(&o->current_directory_set, path)) {
1135                         const char *new_path = unique_path(o, path, add_branch);
1136                         clean_merge = 0;
1137                         output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1138                                "Adding %s as %s",
1139                                conf, path, other_branch, path, new_path);
1140                         remove_file(o, 0, path, 0);
1141                         update_file(o, 0, sha, mode, new_path);
1142                 } else {
1143                         output(o, 2, "Adding %s", path);
1144                         update_file(o, 1, sha, mode, path);
1145                 }
1146         } else if (a_sha && b_sha) {
1147                 /* Case C: Added in both (check for same permissions) and */
1148                 /* case D: Modified in both, but differently. */
1149                 const char *reason = "content";
1150                 struct merge_file_info mfi;
1151                 struct diff_filespec one, a, b;
1153                 if (!o_sha) {
1154                         reason = "add/add";
1155                         o_sha = (unsigned char *)null_sha1;
1156                 }
1157                 output(o, 2, "Auto-merging %s", path);
1158                 one.path = a.path = b.path = (char *)path;
1159                 hashcpy(one.sha1, o_sha);
1160                 one.mode = o_mode;
1161                 hashcpy(a.sha1, a_sha);
1162                 a.mode = a_mode;
1163                 hashcpy(b.sha1, b_sha);
1164                 b.mode = b_mode;
1166                 mfi = merge_file(o, &one, &a, &b,
1167                                  o->branch1, o->branch2);
1169                 clean_merge = mfi.clean;
1170                 if (!mfi.clean) {
1171                         if (S_ISGITLINK(mfi.mode))
1172                                 reason = "submodule";
1173                         output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1174                                         reason, path);
1175                 }
1176                 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1177         } else if (!o_sha && !a_sha && !b_sha) {
1178                 /*
1179                  * this entry was deleted altogether. a_mode == 0 means
1180                  * we had that path and want to actively remove it.
1181                  */
1182                 remove_file(o, 1, path, !a_mode);
1183         } else
1184                 die("Fatal merge failure, shouldn't happen.");
1186         return clean_merge;
1189 int merge_trees(struct merge_options *o,
1190                 struct tree *head,
1191                 struct tree *merge,
1192                 struct tree *common,
1193                 struct tree **result)
1195         int code, clean;
1197         if (o->subtree_merge) {
1198                 merge = shift_tree_object(head, merge);
1199                 common = shift_tree_object(head, common);
1200         }
1202         if (sha_eq(common->object.sha1, merge->object.sha1)) {
1203                 output(o, 0, "Already uptodate!");
1204                 *result = head;
1205                 return 1;
1206         }
1208         code = git_merge_trees(o->call_depth, common, head, merge);
1210         if (code != 0) {
1211                 if (show(o, 4) || o->call_depth)
1212                         die("merging of trees %s and %s failed",
1213                             sha1_to_hex(head->object.sha1),
1214                             sha1_to_hex(merge->object.sha1));
1215                 else
1216                         exit(128);
1217         }
1219         if (unmerged_cache()) {
1220                 struct string_list *entries, *re_head, *re_merge;
1221                 int i;
1222                 string_list_clear(&o->current_file_set, 1);
1223                 string_list_clear(&o->current_directory_set, 1);
1224                 get_files_dirs(o, head);
1225                 get_files_dirs(o, merge);
1227                 entries = get_unmerged();
1228                 re_head  = get_renames(o, head, common, head, merge, entries);
1229                 re_merge = get_renames(o, merge, common, head, merge, entries);
1230                 clean = process_renames(o, re_head, re_merge);
1231                 for (i = 0; i < entries->nr; i++) {
1232                         const char *path = entries->items[i].string;
1233                         struct stage_data *e = entries->items[i].util;
1234                         if (!e->processed
1235                                 && !process_entry(o, path, e))
1236                                 clean = 0;
1237                 }
1239                 string_list_clear(re_merge, 0);
1240                 string_list_clear(re_head, 0);
1241                 string_list_clear(entries, 1);
1243         }
1244         else
1245                 clean = 1;
1247         if (o->call_depth)
1248                 *result = write_tree_from_memory(o);
1250         return clean;
1253 static struct commit_list *reverse_commit_list(struct commit_list *list)
1255         struct commit_list *next = NULL, *current, *backup;
1256         for (current = list; current; current = backup) {
1257                 backup = current->next;
1258                 current->next = next;
1259                 next = current;
1260         }
1261         return next;
1264 /*
1265  * Merge the commits h1 and h2, return the resulting virtual
1266  * commit object and a flag indicating the cleanness of the merge.
1267  */
1268 int merge_recursive(struct merge_options *o,
1269                     struct commit *h1,
1270                     struct commit *h2,
1271                     struct commit_list *ca,
1272                     struct commit **result)
1274         struct commit_list *iter;
1275         struct commit *merged_common_ancestors;
1276         struct tree *mrtree = mrtree;
1277         int clean;
1279         if (show(o, 4)) {
1280                 output(o, 4, "Merging:");
1281                 output_commit_title(o, h1);
1282                 output_commit_title(o, h2);
1283         }
1285         if (!ca) {
1286                 ca = get_merge_bases(h1, h2, 1);
1287                 ca = reverse_commit_list(ca);
1288         }
1290         if (show(o, 5)) {
1291                 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1292                 for (iter = ca; iter; iter = iter->next)
1293                         output_commit_title(o, iter->item);
1294         }
1296         merged_common_ancestors = pop_commit(&ca);
1297         if (merged_common_ancestors == NULL) {
1298                 /* if there is no common ancestor, make an empty tree */
1299                 struct tree *tree = xcalloc(1, sizeof(struct tree));
1301                 tree->object.parsed = 1;
1302                 tree->object.type = OBJ_TREE;
1303                 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1304                 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1305         }
1307         for (iter = ca; iter; iter = iter->next) {
1308                 const char *saved_b1, *saved_b2;
1309                 o->call_depth++;
1310                 /*
1311                  * When the merge fails, the result contains files
1312                  * with conflict markers. The cleanness flag is
1313                  * ignored, it was never actually used, as result of
1314                  * merge_trees has always overwritten it: the committed
1315                  * "conflicts" were already resolved.
1316                  */
1317                 discard_cache();
1318                 saved_b1 = o->branch1;
1319                 saved_b2 = o->branch2;
1320                 o->branch1 = "Temporary merge branch 1";
1321                 o->branch2 = "Temporary merge branch 2";
1322                 merge_recursive(o, merged_common_ancestors, iter->item,
1323                                 NULL, &merged_common_ancestors);
1324                 o->branch1 = saved_b1;
1325                 o->branch2 = saved_b2;
1326                 o->call_depth--;
1328                 if (!merged_common_ancestors)
1329                         die("merge returned no commit");
1330         }
1332         discard_cache();
1333         if (!o->call_depth)
1334                 read_cache();
1336         clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1337                             &mrtree);
1339         if (o->call_depth) {
1340                 *result = make_virtual_commit(mrtree, "merged tree");
1341                 commit_list_insert(h1, &(*result)->parents);
1342                 commit_list_insert(h2, &(*result)->parents->next);
1343         }
1344         flush_output(o);
1345         return clean;
1348 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1350         struct object *object;
1352         object = deref_tag(parse_object(sha1), name, strlen(name));
1353         if (!object)
1354                 return NULL;
1355         if (object->type == OBJ_TREE)
1356                 return make_virtual_commit((struct tree*)object, name);
1357         if (object->type != OBJ_COMMIT)
1358                 return NULL;
1359         if (parse_commit((struct commit *)object))
1360                 return NULL;
1361         return (struct commit *)object;
1364 int merge_recursive_generic(struct merge_options *o,
1365                             const unsigned char *head,
1366                             const unsigned char *merge,
1367                             int num_base_list,
1368                             const unsigned char **base_list,
1369                             struct commit **result)
1371         int clean, index_fd;
1372         struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1373         struct commit *head_commit = get_ref(head, o->branch1);
1374         struct commit *next_commit = get_ref(merge, o->branch2);
1375         struct commit_list *ca = NULL;
1377         if (base_list) {
1378                 int i;
1379                 for (i = 0; i < num_base_list; ++i) {
1380                         struct commit *base;
1381                         if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1382                                 return error("Could not parse object '%s'",
1383                                         sha1_to_hex(base_list[i]));
1384                         commit_list_insert(base, &ca);
1385                 }
1386         }
1388         index_fd = hold_locked_index(lock, 1);
1389         clean = merge_recursive(o, head_commit, next_commit, ca,
1390                         result);
1391         if (active_cache_changed &&
1392                         (write_cache(index_fd, active_cache, active_nr) ||
1393                          commit_locked_index(lock)))
1394                 return error("Unable to write index.");
1396         return clean ? 0 : 1;
1399 static int merge_recursive_config(const char *var, const char *value, void *cb)
1401         struct merge_options *o = cb;
1402         if (!strcasecmp(var, "merge.verbosity")) {
1403                 o->verbosity = git_config_int(var, value);
1404                 return 0;
1405         }
1406         if (!strcasecmp(var, "diff.renamelimit")) {
1407                 o->diff_rename_limit = git_config_int(var, value);
1408                 return 0;
1409         }
1410         if (!strcasecmp(var, "merge.renamelimit")) {
1411                 o->merge_rename_limit = git_config_int(var, value);
1412                 return 0;
1413         }
1414         return git_xmerge_config(var, value, cb);
1417 void init_merge_options(struct merge_options *o)
1419         memset(o, 0, sizeof(struct merge_options));
1420         o->verbosity = 2;
1421         o->buffer_output = 1;
1422         o->diff_rename_limit = -1;
1423         o->merge_rename_limit = -1;
1424         git_config(merge_recursive_config, o);
1425         if (getenv("GIT_MERGE_VERBOSITY"))
1426                 o->verbosity =
1427                         strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1428         if (o->verbosity >= 5)
1429                 o->buffer_output = 0;
1430         strbuf_init(&o->obuf, 0);
1431         memset(&o->current_file_set, 0, sizeof(struct string_list));
1432         o->current_file_set.strdup_strings = 1;
1433         memset(&o->current_directory_set, 0, sizeof(struct string_list));
1434         o->current_directory_set.strdup_strings = 1;