Code

gitweb: accept trailing "/" in $project_list
[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"
23 #include "submodule.h"
25 static struct tree *shift_tree_object(struct tree *one, struct tree *two,
26                                       const char *subtree_shift)
27 {
28         unsigned char shifted[20];
30         if (!*subtree_shift) {
31                 shift_tree(one->object.sha1, two->object.sha1, shifted, 0);
32         } else {
33                 shift_tree_by(one->object.sha1, two->object.sha1, shifted,
34                               subtree_shift);
35         }
36         if (!hashcmp(two->object.sha1, shifted))
37                 return two;
38         return lookup_tree(shifted);
39 }
41 /*
42  * A virtual commit has (const char *)commit->util set to the name.
43  */
45 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
46 {
47         struct commit *commit = xcalloc(1, sizeof(struct commit));
48         commit->tree = tree;
49         commit->util = (void*)comment;
50         /* avoid warnings */
51         commit->object.parsed = 1;
52         return commit;
53 }
55 /*
56  * Since we use get_tree_entry(), which does not put the read object into
57  * the object pool, we cannot rely on a == b.
58  */
59 static int sha_eq(const unsigned char *a, const unsigned char *b)
60 {
61         if (!a && !b)
62                 return 2;
63         return a && b && hashcmp(a, b) == 0;
64 }
66 enum rename_type {
67         RENAME_NORMAL = 0,
68         RENAME_DELETE,
69         RENAME_ONE_FILE_TO_TWO
70 };
72 struct rename_df_conflict_info {
73         enum rename_type rename_type;
74         struct diff_filepair *pair1;
75         struct diff_filepair *pair2;
76         const char *branch1;
77         const char *branch2;
78         struct stage_data *dst_entry1;
79         struct stage_data *dst_entry2;
80 };
82 /*
83  * Since we want to write the index eventually, we cannot reuse the index
84  * for these (temporary) data.
85  */
86 struct stage_data {
87         struct {
88                 unsigned mode;
89                 unsigned char sha[20];
90         } stages[4];
91         struct rename_df_conflict_info *rename_df_conflict_info;
92         unsigned processed:1;
93 };
95 static inline void setup_rename_df_conflict_info(enum rename_type rename_type,
96                                                  struct diff_filepair *pair1,
97                                                  struct diff_filepair *pair2,
98                                                  const char *branch1,
99                                                  const char *branch2,
100                                                  struct stage_data *dst_entry1,
101                                                  struct stage_data *dst_entry2)
103         struct rename_df_conflict_info *ci = xcalloc(1, sizeof(struct rename_df_conflict_info));
104         ci->rename_type = rename_type;
105         ci->pair1 = pair1;
106         ci->branch1 = branch1;
107         ci->branch2 = branch2;
109         ci->dst_entry1 = dst_entry1;
110         dst_entry1->rename_df_conflict_info = ci;
111         dst_entry1->processed = 0;
113         assert(!pair2 == !dst_entry2);
114         if (dst_entry2) {
115                 ci->dst_entry2 = dst_entry2;
116                 ci->pair2 = pair2;
117                 dst_entry2->rename_df_conflict_info = ci;
118                 dst_entry2->processed = 0;
119         }
122 static int show(struct merge_options *o, int v)
124         return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
127 static void flush_output(struct merge_options *o)
129         if (o->obuf.len) {
130                 fputs(o->obuf.buf, stdout);
131                 strbuf_reset(&o->obuf);
132         }
135 __attribute__((format (printf, 3, 4)))
136 static void output(struct merge_options *o, int v, const char *fmt, ...)
138         va_list ap;
140         if (!show(o, v))
141                 return;
143         strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
144         memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
145         strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
147         va_start(ap, fmt);
148         strbuf_vaddf(&o->obuf, fmt, ap);
149         va_end(ap);
151         strbuf_add(&o->obuf, "\n", 1);
152         if (!o->buffer_output)
153                 flush_output(o);
156 static void output_commit_title(struct merge_options *o, struct commit *commit)
158         int i;
159         flush_output(o);
160         for (i = o->call_depth; i--;)
161                 fputs("  ", stdout);
162         if (commit->util)
163                 printf("virtual %s\n", (char *)commit->util);
164         else {
165                 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
166                 if (parse_commit(commit) != 0)
167                         printf("(bad commit)\n");
168                 else {
169                         const char *title;
170                         int len = find_commit_subject(commit->buffer, &title);
171                         if (len)
172                                 printf("%.*s\n", len, title);
173                 }
174         }
177 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
178                 const char *path, int stage, int refresh, int options)
180         struct cache_entry *ce;
181         ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
182         if (!ce)
183                 return error("addinfo_cache failed for path '%s'", path);
184         return add_cache_entry(ce, options);
187 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
189         parse_tree(tree);
190         init_tree_desc(desc, tree->buffer, tree->size);
193 static int git_merge_trees(int index_only,
194                            struct tree *common,
195                            struct tree *head,
196                            struct tree *merge)
198         int rc;
199         struct tree_desc t[3];
200         struct unpack_trees_options opts;
202         memset(&opts, 0, sizeof(opts));
203         if (index_only)
204                 opts.index_only = 1;
205         else
206                 opts.update = 1;
207         opts.merge = 1;
208         opts.head_idx = 2;
209         opts.fn = threeway_merge;
210         opts.src_index = &the_index;
211         opts.dst_index = &the_index;
212         setup_unpack_trees_porcelain(&opts, "merge");
214         init_tree_desc_from_tree(t+0, common);
215         init_tree_desc_from_tree(t+1, head);
216         init_tree_desc_from_tree(t+2, merge);
218         rc = unpack_trees(3, t, &opts);
219         cache_tree_free(&active_cache_tree);
220         return rc;
223 struct tree *write_tree_from_memory(struct merge_options *o)
225         struct tree *result = NULL;
227         if (unmerged_cache()) {
228                 int i;
229                 fprintf(stderr, "BUG: There are unmerged index entries:\n");
230                 for (i = 0; i < active_nr; i++) {
231                         struct cache_entry *ce = active_cache[i];
232                         if (ce_stage(ce))
233                                 fprintf(stderr, "BUG: %d %.*s", ce_stage(ce),
234                                         (int)ce_namelen(ce), ce->name);
235                 }
236                 die("Bug in merge-recursive.c");
237         }
239         if (!active_cache_tree)
240                 active_cache_tree = cache_tree();
242         if (!cache_tree_fully_valid(active_cache_tree) &&
243             cache_tree_update(active_cache_tree,
244                               active_cache, active_nr, 0, 0) < 0)
245                 die("error building trees");
247         result = lookup_tree(active_cache_tree->sha1);
249         return result;
252 static int save_files_dirs(const unsigned char *sha1,
253                 const char *base, int baselen, const char *path,
254                 unsigned int mode, int stage, void *context)
256         int len = strlen(path);
257         char *newpath = xmalloc(baselen + len + 1);
258         struct merge_options *o = context;
260         memcpy(newpath, base, baselen);
261         memcpy(newpath + baselen, path, len);
262         newpath[baselen + len] = '\0';
264         if (S_ISDIR(mode))
265                 string_list_insert(&o->current_directory_set, newpath);
266         else
267                 string_list_insert(&o->current_file_set, newpath);
268         free(newpath);
270         return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
273 static int get_files_dirs(struct merge_options *o, struct tree *tree)
275         int n;
276         if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
277                 return 0;
278         n = o->current_file_set.nr + o->current_directory_set.nr;
279         return n;
282 /*
283  * Returns an index_entry instance which doesn't have to correspond to
284  * a real cache entry in Git's index.
285  */
286 static struct stage_data *insert_stage_data(const char *path,
287                 struct tree *o, struct tree *a, struct tree *b,
288                 struct string_list *entries)
290         struct string_list_item *item;
291         struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
292         get_tree_entry(o->object.sha1, path,
293                         e->stages[1].sha, &e->stages[1].mode);
294         get_tree_entry(a->object.sha1, path,
295                         e->stages[2].sha, &e->stages[2].mode);
296         get_tree_entry(b->object.sha1, path,
297                         e->stages[3].sha, &e->stages[3].mode);
298         item = string_list_insert(entries, path);
299         item->util = e;
300         return e;
303 /*
304  * Create a dictionary mapping file names to stage_data objects. The
305  * dictionary contains one entry for every path with a non-zero stage entry.
306  */
307 static struct string_list *get_unmerged(void)
309         struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
310         int i;
312         unmerged->strdup_strings = 1;
314         for (i = 0; i < active_nr; i++) {
315                 struct string_list_item *item;
316                 struct stage_data *e;
317                 struct cache_entry *ce = active_cache[i];
318                 if (!ce_stage(ce))
319                         continue;
321                 item = string_list_lookup(unmerged, ce->name);
322                 if (!item) {
323                         item = string_list_insert(unmerged, ce->name);
324                         item->util = xcalloc(1, sizeof(struct stage_data));
325                 }
326                 e = item->util;
327                 e->stages[ce_stage(ce)].mode = ce->ce_mode;
328                 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
329         }
331         return unmerged;
334 static void make_room_for_directories_of_df_conflicts(struct merge_options *o,
335                                                       struct string_list *entries)
337         /* If there are D/F conflicts, and the paths currently exist
338          * in the working copy as a file, we want to remove them to
339          * make room for the corresponding directory.  Such paths will
340          * later be processed in process_df_entry() at the end.  If
341          * the corresponding directory ends up being removed by the
342          * merge, then the file will be reinstated at that time
343          * (albeit with a different timestamp!); otherwise, if the
344          * file is not supposed to be removed by the merge, the
345          * contents of the file will be placed in another unique
346          * filename.
347          *
348          * NOTE: This function relies on the fact that entries for a
349          * D/F conflict will appear adjacent in the index, with the
350          * entries for the file appearing before entries for paths
351          * below the corresponding directory.
352          */
353         const char *last_file = NULL;
354         int last_len = 0;
355         int i;
357         /*
358          * Do not do any of this crazyness during the recursive; we don't
359          * even write anything to the working tree!
360          */
361         if (o->call_depth)
362                 return;
364         for (i = 0; i < entries->nr; i++) {
365                 const char *path = entries->items[i].string;
366                 int len = strlen(path);
367                 struct stage_data *e = entries->items[i].util;
369                 /*
370                  * Check if last_file & path correspond to a D/F conflict;
371                  * i.e. whether path is last_file+'/'+<something>.
372                  * If so, remove last_file to make room for path and friends.
373                  */
374                 if (last_file &&
375                     len > last_len &&
376                     memcmp(path, last_file, last_len) == 0 &&
377                     path[last_len] == '/') {
378                         output(o, 3, "Removing %s to make room for subdirectory; may re-add later.", last_file);
379                         unlink(last_file);
380                 }
382                 /*
383                  * Determine whether path could exist as a file in the
384                  * working directory as a possible D/F conflict.  This
385                  * will only occur when it exists in stage 2 as a
386                  * file.
387                  */
388                 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
389                         last_file = path;
390                         last_len = len;
391                 } else {
392                         last_file = NULL;
393                 }
394         }
397 struct rename {
398         struct diff_filepair *pair;
399         struct stage_data *src_entry;
400         struct stage_data *dst_entry;
401         unsigned processed:1;
402 };
404 /*
405  * Get information of all renames which occurred between 'o_tree' and
406  * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
407  * 'b_tree') to be able to associate the correct cache entries with
408  * the rename information. 'tree' is always equal to either a_tree or b_tree.
409  */
410 static struct string_list *get_renames(struct merge_options *o,
411                                        struct tree *tree,
412                                        struct tree *o_tree,
413                                        struct tree *a_tree,
414                                        struct tree *b_tree,
415                                        struct string_list *entries)
417         int i;
418         struct string_list *renames;
419         struct diff_options opts;
421         renames = xcalloc(1, sizeof(struct string_list));
422         diff_setup(&opts);
423         DIFF_OPT_SET(&opts, RECURSIVE);
424         opts.detect_rename = DIFF_DETECT_RENAME;
425         opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
426                             o->diff_rename_limit >= 0 ? o->diff_rename_limit :
427                             1000;
428         opts.rename_score = o->rename_score;
429         opts.show_rename_progress = o->show_rename_progress;
430         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
431         if (diff_setup_done(&opts) < 0)
432                 die("diff setup failed");
433         diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
434         diffcore_std(&opts);
435         if (opts.needed_rename_limit > o->needed_rename_limit)
436                 o->needed_rename_limit = opts.needed_rename_limit;
437         for (i = 0; i < diff_queued_diff.nr; ++i) {
438                 struct string_list_item *item;
439                 struct rename *re;
440                 struct diff_filepair *pair = diff_queued_diff.queue[i];
441                 if (pair->status != 'R') {
442                         diff_free_filepair(pair);
443                         continue;
444                 }
445                 re = xmalloc(sizeof(*re));
446                 re->processed = 0;
447                 re->pair = pair;
448                 item = string_list_lookup(entries, re->pair->one->path);
449                 if (!item)
450                         re->src_entry = insert_stage_data(re->pair->one->path,
451                                         o_tree, a_tree, b_tree, entries);
452                 else
453                         re->src_entry = item->util;
455                 item = string_list_lookup(entries, re->pair->two->path);
456                 if (!item)
457                         re->dst_entry = insert_stage_data(re->pair->two->path,
458                                         o_tree, a_tree, b_tree, entries);
459                 else
460                         re->dst_entry = item->util;
461                 item = string_list_insert(renames, pair->one->path);
462                 item->util = re;
463         }
464         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
465         diff_queued_diff.nr = 0;
466         diff_flush(&opts);
467         return renames;
470 static int update_stages_options(const char *path, struct diff_filespec *o,
471                          struct diff_filespec *a, struct diff_filespec *b,
472                          int clear, int options)
474         if (clear)
475                 if (remove_file_from_cache(path))
476                         return -1;
477         if (o)
478                 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
479                         return -1;
480         if (a)
481                 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
482                         return -1;
483         if (b)
484                 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
485                         return -1;
486         return 0;
489 static int update_stages(const char *path, struct diff_filespec *o,
490                          struct diff_filespec *a, struct diff_filespec *b,
491                          int clear)
493         int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
494         return update_stages_options(path, o, a, b, clear, options);
497 static int update_stages_and_entry(const char *path,
498                                    struct stage_data *entry,
499                                    struct diff_filespec *o,
500                                    struct diff_filespec *a,
501                                    struct diff_filespec *b,
502                                    int clear)
504         int options;
506         entry->processed = 0;
507         entry->stages[1].mode = o->mode;
508         entry->stages[2].mode = a->mode;
509         entry->stages[3].mode = b->mode;
510         hashcpy(entry->stages[1].sha, o->sha1);
511         hashcpy(entry->stages[2].sha, a->sha1);
512         hashcpy(entry->stages[3].sha, b->sha1);
513         options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
514         return update_stages_options(path, o, a, b, clear, options);
517 static int remove_file(struct merge_options *o, int clean,
518                        const char *path, int no_wd)
520         int update_cache = o->call_depth || clean;
521         int update_working_directory = !o->call_depth && !no_wd;
523         if (update_cache) {
524                 if (remove_file_from_cache(path))
525                         return -1;
526         }
527         if (update_working_directory) {
528                 if (remove_path(path))
529                         return -1;
530         }
531         return 0;
534 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
536         char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
537         int suffix = 0;
538         struct stat st;
539         char *p = newpath + strlen(path);
540         strcpy(newpath, path);
541         *(p++) = '~';
542         strcpy(p, branch);
543         for (; *p; ++p)
544                 if ('/' == *p)
545                         *p = '_';
546         while (string_list_has_string(&o->current_file_set, newpath) ||
547                string_list_has_string(&o->current_directory_set, newpath) ||
548                lstat(newpath, &st) == 0)
549                 sprintf(p, "_%d", suffix++);
551         string_list_insert(&o->current_file_set, newpath);
552         return newpath;
555 static void flush_buffer(int fd, const char *buf, unsigned long size)
557         while (size > 0) {
558                 long ret = write_in_full(fd, buf, size);
559                 if (ret < 0) {
560                         /* Ignore epipe */
561                         if (errno == EPIPE)
562                                 break;
563                         die_errno("merge-recursive");
564                 } else if (!ret) {
565                         die("merge-recursive: disk full?");
566                 }
567                 size -= ret;
568                 buf += ret;
569         }
572 static int would_lose_untracked(const char *path)
574         int pos = cache_name_pos(path, strlen(path));
576         if (pos < 0)
577                 pos = -1 - pos;
578         while (pos < active_nr &&
579                !strcmp(path, active_cache[pos]->name)) {
580                 /*
581                  * If stage #0, it is definitely tracked.
582                  * If it has stage #2 then it was tracked
583                  * before this merge started.  All other
584                  * cases the path was not tracked.
585                  */
586                 switch (ce_stage(active_cache[pos])) {
587                 case 0:
588                 case 2:
589                         return 0;
590                 }
591                 pos++;
592         }
593         return file_exists(path);
596 static int make_room_for_path(const char *path)
598         int status;
599         const char *msg = "failed to create path '%s'%s";
601         status = safe_create_leading_directories_const(path);
602         if (status) {
603                 if (status == -3) {
604                         /* something else exists */
605                         error(msg, path, ": perhaps a D/F conflict?");
606                         return -1;
607                 }
608                 die(msg, path, "");
609         }
611         /*
612          * Do not unlink a file in the work tree if we are not
613          * tracking it.
614          */
615         if (would_lose_untracked(path))
616                 return error("refusing to lose untracked file at '%s'",
617                              path);
619         /* Successful unlink is good.. */
620         if (!unlink(path))
621                 return 0;
622         /* .. and so is no existing file */
623         if (errno == ENOENT)
624                 return 0;
625         /* .. but not some other error (who really cares what?) */
626         return error(msg, path, ": perhaps a D/F conflict?");
629 static void update_file_flags(struct merge_options *o,
630                               const unsigned char *sha,
631                               unsigned mode,
632                               const char *path,
633                               int update_cache,
634                               int update_wd)
636         if (o->call_depth)
637                 update_wd = 0;
639         if (update_wd) {
640                 enum object_type type;
641                 void *buf;
642                 unsigned long size;
644                 if (S_ISGITLINK(mode)) {
645                         /*
646                          * We may later decide to recursively descend into
647                          * the submodule directory and update its index
648                          * and/or work tree, but we do not do that now.
649                          */
650                         update_wd = 0;
651                         goto update_index;
652                 }
654                 buf = read_sha1_file(sha, &type, &size);
655                 if (!buf)
656                         die("cannot read object %s '%s'", sha1_to_hex(sha), path);
657                 if (type != OBJ_BLOB)
658                         die("blob expected for %s '%s'", sha1_to_hex(sha), path);
659                 if (S_ISREG(mode)) {
660                         struct strbuf strbuf = STRBUF_INIT;
661                         if (convert_to_working_tree(path, buf, size, &strbuf)) {
662                                 free(buf);
663                                 size = strbuf.len;
664                                 buf = strbuf_detach(&strbuf, NULL);
665                         }
666                 }
668                 if (make_room_for_path(path) < 0) {
669                         update_wd = 0;
670                         free(buf);
671                         goto update_index;
672                 }
673                 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
674                         int fd;
675                         if (mode & 0100)
676                                 mode = 0777;
677                         else
678                                 mode = 0666;
679                         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
680                         if (fd < 0)
681                                 die_errno("failed to open '%s'", path);
682                         flush_buffer(fd, buf, size);
683                         close(fd);
684                 } else if (S_ISLNK(mode)) {
685                         char *lnk = xmemdupz(buf, size);
686                         safe_create_leading_directories_const(path);
687                         unlink(path);
688                         if (symlink(lnk, path))
689                                 die_errno("failed to symlink '%s'", path);
690                         free(lnk);
691                 } else
692                         die("do not know what to do with %06o %s '%s'",
693                             mode, sha1_to_hex(sha), path);
694                 free(buf);
695         }
696  update_index:
697         if (update_cache)
698                 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
701 static void update_file(struct merge_options *o,
702                         int clean,
703                         const unsigned char *sha,
704                         unsigned mode,
705                         const char *path)
707         update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
710 /* Low level file merging, update and removal */
712 struct merge_file_info {
713         unsigned char sha[20];
714         unsigned mode;
715         unsigned clean:1,
716                  merge:1;
717 };
719 static int merge_3way(struct merge_options *o,
720                       mmbuffer_t *result_buf,
721                       struct diff_filespec *one,
722                       struct diff_filespec *a,
723                       struct diff_filespec *b,
724                       const char *branch1,
725                       const char *branch2)
727         mmfile_t orig, src1, src2;
728         struct ll_merge_options ll_opts = {0};
729         char *base_name, *name1, *name2;
730         int merge_status;
732         ll_opts.renormalize = o->renormalize;
733         ll_opts.xdl_opts = o->xdl_opts;
735         if (o->call_depth) {
736                 ll_opts.virtual_ancestor = 1;
737                 ll_opts.variant = 0;
738         } else {
739                 switch (o->recursive_variant) {
740                 case MERGE_RECURSIVE_OURS:
741                         ll_opts.variant = XDL_MERGE_FAVOR_OURS;
742                         break;
743                 case MERGE_RECURSIVE_THEIRS:
744                         ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
745                         break;
746                 default:
747                         ll_opts.variant = 0;
748                         break;
749                 }
750         }
752         if (strcmp(a->path, b->path) ||
753             (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
754                 base_name = o->ancestor == NULL ? NULL :
755                         xstrdup(mkpath("%s:%s", o->ancestor, one->path));
756                 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
757                 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
758         } else {
759                 base_name = o->ancestor == NULL ? NULL :
760                         xstrdup(mkpath("%s", o->ancestor));
761                 name1 = xstrdup(mkpath("%s", branch1));
762                 name2 = xstrdup(mkpath("%s", branch2));
763         }
765         read_mmblob(&orig, one->sha1);
766         read_mmblob(&src1, a->sha1);
767         read_mmblob(&src2, b->sha1);
769         merge_status = ll_merge(result_buf, a->path, &orig, base_name,
770                                 &src1, name1, &src2, name2, &ll_opts);
772         free(name1);
773         free(name2);
774         free(orig.ptr);
775         free(src1.ptr);
776         free(src2.ptr);
777         return merge_status;
780 static struct merge_file_info merge_file(struct merge_options *o,
781                                          struct diff_filespec *one,
782                                          struct diff_filespec *a,
783                                          struct diff_filespec *b,
784                                          const char *branch1,
785                                          const char *branch2)
787         struct merge_file_info result;
788         result.merge = 0;
789         result.clean = 1;
791         if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
792                 result.clean = 0;
793                 if (S_ISREG(a->mode)) {
794                         result.mode = a->mode;
795                         hashcpy(result.sha, a->sha1);
796                 } else {
797                         result.mode = b->mode;
798                         hashcpy(result.sha, b->sha1);
799                 }
800         } else {
801                 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
802                         result.merge = 1;
804                 /*
805                  * Merge modes
806                  */
807                 if (a->mode == b->mode || a->mode == one->mode)
808                         result.mode = b->mode;
809                 else {
810                         result.mode = a->mode;
811                         if (b->mode != one->mode) {
812                                 result.clean = 0;
813                                 result.merge = 1;
814                         }
815                 }
817                 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
818                         hashcpy(result.sha, b->sha1);
819                 else if (sha_eq(b->sha1, one->sha1))
820                         hashcpy(result.sha, a->sha1);
821                 else if (S_ISREG(a->mode)) {
822                         mmbuffer_t result_buf;
823                         int merge_status;
825                         merge_status = merge_3way(o, &result_buf, one, a, b,
826                                                   branch1, branch2);
828                         if ((merge_status < 0) || !result_buf.ptr)
829                                 die("Failed to execute internal merge");
831                         if (write_sha1_file(result_buf.ptr, result_buf.size,
832                                             blob_type, result.sha))
833                                 die("Unable to add %s to database",
834                                     a->path);
836                         free(result_buf.ptr);
837                         result.clean = (merge_status == 0);
838                 } else if (S_ISGITLINK(a->mode)) {
839                         result.clean = merge_submodule(result.sha, one->path, one->sha1,
840                                                        a->sha1, b->sha1);
841                 } else if (S_ISLNK(a->mode)) {
842                         hashcpy(result.sha, a->sha1);
844                         if (!sha_eq(a->sha1, b->sha1))
845                                 result.clean = 0;
846                 } else {
847                         die("unsupported object type in the tree");
848                 }
849         }
851         return result;
854 static void conflict_rename_delete(struct merge_options *o,
855                                    struct diff_filepair *pair,
856                                    const char *rename_branch,
857                                    const char *other_branch)
859         char *dest_name = pair->two->path;
860         int df_conflict = 0;
861         struct stat st;
863         output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
864                "and deleted in %s",
865                pair->one->path, pair->two->path, rename_branch,
866                other_branch);
867         if (!o->call_depth)
868                 update_stages(dest_name, NULL,
869                               rename_branch == o->branch1 ? pair->two : NULL,
870                               rename_branch == o->branch1 ? NULL : pair->two,
871                               1);
872         if (lstat(dest_name, &st) == 0 && S_ISDIR(st.st_mode)) {
873                 dest_name = unique_path(o, dest_name, rename_branch);
874                 df_conflict = 1;
875         }
876         update_file(o, 0, pair->two->sha1, pair->two->mode, dest_name);
877         if (df_conflict)
878                 free(dest_name);
881 static void conflict_rename_rename_1to2(struct merge_options *o,
882                                         struct diff_filepair *pair1,
883                                         const char *branch1,
884                                         struct diff_filepair *pair2,
885                                         const char *branch2)
887         /* One file was renamed in both branches, but to different names. */
888         char *del[2];
889         int delp = 0;
890         const char *ren1_dst = pair1->two->path;
891         const char *ren2_dst = pair2->two->path;
892         const char *dst_name1 = ren1_dst;
893         const char *dst_name2 = ren2_dst;
894         struct stat st;
895         if (lstat(ren1_dst, &st) == 0 && S_ISDIR(st.st_mode)) {
896                 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
897                 output(o, 1, "%s is a directory in %s adding as %s instead",
898                        ren1_dst, branch2, dst_name1);
899         }
900         if (lstat(ren2_dst, &st) == 0 && S_ISDIR(st.st_mode)) {
901                 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
902                 output(o, 1, "%s is a directory in %s adding as %s instead",
903                        ren2_dst, branch1, dst_name2);
904         }
905         if (o->call_depth) {
906                 remove_file_from_cache(dst_name1);
907                 remove_file_from_cache(dst_name2);
908                 /*
909                  * Uncomment to leave the conflicting names in the resulting tree
910                  *
911                  * update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1);
912                  * update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2);
913                  */
914         } else {
915                 update_stages(ren1_dst, NULL, pair1->two, NULL, 1);
916                 update_stages(ren2_dst, NULL, NULL, pair2->two, 1);
918                 update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1);
919                 update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2);
920         }
921         while (delp--)
922                 free(del[delp]);
925 static void conflict_rename_rename_2to1(struct merge_options *o,
926                                         struct rename *ren1,
927                                         const char *branch1,
928                                         struct rename *ren2,
929                                         const char *branch2)
931         /* Two files were renamed to the same thing. */
932         char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
933         char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
934         output(o, 1, "Renaming %s to %s and %s to %s instead",
935                ren1->pair->one->path, new_path1,
936                ren2->pair->one->path, new_path2);
937         remove_file(o, 0, ren1->pair->two->path, 0);
938         update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
939         update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
940         free(new_path2);
941         free(new_path1);
944 static int process_renames(struct merge_options *o,
945                            struct string_list *a_renames,
946                            struct string_list *b_renames)
948         int clean_merge = 1, i, j;
949         struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
950         struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
951         const struct rename *sre;
953         for (i = 0; i < a_renames->nr; i++) {
954                 sre = a_renames->items[i].util;
955                 string_list_insert(&a_by_dst, sre->pair->two->path)->util
956                         = sre->dst_entry;
957         }
958         for (i = 0; i < b_renames->nr; i++) {
959                 sre = b_renames->items[i].util;
960                 string_list_insert(&b_by_dst, sre->pair->two->path)->util
961                         = sre->dst_entry;
962         }
964         for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
965                 struct string_list *renames1, *renames2Dst;
966                 struct rename *ren1 = NULL, *ren2 = NULL;
967                 const char *branch1, *branch2;
968                 const char *ren1_src, *ren1_dst;
970                 if (i >= a_renames->nr) {
971                         ren2 = b_renames->items[j++].util;
972                 } else if (j >= b_renames->nr) {
973                         ren1 = a_renames->items[i++].util;
974                 } else {
975                         int compare = strcmp(a_renames->items[i].string,
976                                              b_renames->items[j].string);
977                         if (compare <= 0)
978                                 ren1 = a_renames->items[i++].util;
979                         if (compare >= 0)
980                                 ren2 = b_renames->items[j++].util;
981                 }
983                 /* TODO: refactor, so that 1/2 are not needed */
984                 if (ren1) {
985                         renames1 = a_renames;
986                         renames2Dst = &b_by_dst;
987                         branch1 = o->branch1;
988                         branch2 = o->branch2;
989                 } else {
990                         struct rename *tmp;
991                         renames1 = b_renames;
992                         renames2Dst = &a_by_dst;
993                         branch1 = o->branch2;
994                         branch2 = o->branch1;
995                         tmp = ren2;
996                         ren2 = ren1;
997                         ren1 = tmp;
998                 }
1000                 ren1->dst_entry->processed = 1;
1001                 ren1->src_entry->processed = 1;
1003                 if (ren1->processed)
1004                         continue;
1005                 ren1->processed = 1;
1007                 ren1_src = ren1->pair->one->path;
1008                 ren1_dst = ren1->pair->two->path;
1010                 if (ren2) {
1011                         const char *ren2_src = ren2->pair->one->path;
1012                         const char *ren2_dst = ren2->pair->two->path;
1013                         /* Renamed in 1 and renamed in 2 */
1014                         if (strcmp(ren1_src, ren2_src) != 0)
1015                                 die("ren1.src != ren2.src");
1016                         ren2->dst_entry->processed = 1;
1017                         ren2->processed = 1;
1018                         if (strcmp(ren1_dst, ren2_dst) != 0) {
1019                                 setup_rename_df_conflict_info(RENAME_ONE_FILE_TO_TWO,
1020                                                               ren1->pair,
1021                                                               ren2->pair,
1022                                                               branch1,
1023                                                               branch2,
1024                                                               ren1->dst_entry,
1025                                                               ren2->dst_entry);
1026                         } else {
1027                                 remove_file(o, 1, ren1_src, 1);
1028                                 update_stages_and_entry(ren1_dst,
1029                                                         ren1->dst_entry,
1030                                                         ren1->pair->one,
1031                                                         ren1->pair->two,
1032                                                         ren2->pair->two,
1033                                                         1 /* clear */);
1034                         }
1035                 } else {
1036                         /* Renamed in 1, maybe changed in 2 */
1037                         struct string_list_item *item;
1038                         /* we only use sha1 and mode of these */
1039                         struct diff_filespec src_other, dst_other;
1040                         int try_merge;
1042                         /*
1043                          * unpack_trees loads entries from common-commit
1044                          * into stage 1, from head-commit into stage 2, and
1045                          * from merge-commit into stage 3.  We keep track
1046                          * of which side corresponds to the rename.
1047                          */
1048                         int renamed_stage = a_renames == renames1 ? 2 : 3;
1049                         int other_stage =   a_renames == renames1 ? 3 : 2;
1051                         remove_file(o, 1, ren1_src, o->call_depth || renamed_stage == 2);
1053                         hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
1054                         src_other.mode = ren1->src_entry->stages[other_stage].mode;
1055                         hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
1056                         dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1057                         try_merge = 0;
1059                         if (sha_eq(src_other.sha1, null_sha1)) {
1060                                 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
1061                                         ren1->dst_entry->processed = 0;
1062                                         setup_rename_df_conflict_info(RENAME_DELETE,
1063                                                                       ren1->pair,
1064                                                                       NULL,
1065                                                                       branch1,
1066                                                                       branch2,
1067                                                                       ren1->dst_entry,
1068                                                                       NULL);
1069                                 } else {
1070                                         clean_merge = 0;
1071                                         conflict_rename_delete(o, ren1->pair, branch1, branch2);
1072                                 }
1073                         } else if ((dst_other.mode == ren1->pair->two->mode) &&
1074                                    sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
1075                                 /* Added file on the other side
1076                                    identical to the file being
1077                                    renamed: clean merge */
1078                                 update_file(o, 1, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
1079                         } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1080                                 const char *new_path;
1081                                 clean_merge = 0;
1082                                 try_merge = 1;
1083                                 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
1084                                        "%s added in %s",
1085                                        ren1_src, ren1_dst, branch1,
1086                                        ren1_dst, branch2);
1087                                 if (o->call_depth) {
1088                                         struct merge_file_info mfi;
1089                                         struct diff_filespec one, a, b;
1091                                         one.path = a.path = b.path =
1092                                                 (char *)ren1_dst;
1093                                         hashcpy(one.sha1, null_sha1);
1094                                         one.mode = 0;
1095                                         hashcpy(a.sha1, ren1->pair->two->sha1);
1096                                         a.mode = ren1->pair->two->mode;
1097                                         hashcpy(b.sha1, dst_other.sha1);
1098                                         b.mode = dst_other.mode;
1099                                         mfi = merge_file(o, &one, &a, &b,
1100                                                          branch1,
1101                                                          branch2);
1102                                         output(o, 1, "Adding merged %s", ren1_dst);
1103                                         update_file(o, 0,
1104                                                     mfi.sha,
1105                                                     mfi.mode,
1106                                                     ren1_dst);
1107                                         try_merge = 0;
1108                                 } else {
1109                                         new_path = unique_path(o, ren1_dst, branch2);
1110                                         output(o, 1, "Adding as %s instead", new_path);
1111                                         update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
1112                                 }
1113                         } else if ((item = string_list_lookup(renames2Dst, ren1_dst))) {
1114                                 ren2 = item->util;
1115                                 clean_merge = 0;
1116                                 ren2->processed = 1;
1117                                 output(o, 1, "CONFLICT (rename/rename): "
1118                                        "Rename %s->%s in %s. "
1119                                        "Rename %s->%s in %s",
1120                                        ren1_src, ren1_dst, branch1,
1121                                        ren2->pair->one->path, ren2->pair->two->path, branch2);
1122                                 conflict_rename_rename_2to1(o, ren1, branch1, ren2, branch2);
1123                         } else
1124                                 try_merge = 1;
1126                         if (try_merge) {
1127                                 struct diff_filespec *one, *a, *b;
1128                                 src_other.path = (char *)ren1_src;
1130                                 one = ren1->pair->one;
1131                                 if (a_renames == renames1) {
1132                                         a = ren1->pair->two;
1133                                         b = &src_other;
1134                                 } else {
1135                                         b = ren1->pair->two;
1136                                         a = &src_other;
1137                                 }
1138                                 update_stages_and_entry(ren1_dst, ren1->dst_entry, one, a, b, 1);
1139                                 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
1140                                         setup_rename_df_conflict_info(RENAME_NORMAL,
1141                                                                       ren1->pair,
1142                                                                       NULL,
1143                                                                       branch1,
1144                                                                       NULL,
1145                                                                       ren1->dst_entry,
1146                                                                       NULL);
1147                                 }
1148                         }
1149                 }
1150         }
1151         string_list_clear(&a_by_dst, 0);
1152         string_list_clear(&b_by_dst, 0);
1154         return clean_merge;
1157 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1159         return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1162 static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1164         void *buf;
1165         enum object_type type;
1166         unsigned long size;
1167         buf = read_sha1_file(sha1, &type, &size);
1168         if (!buf)
1169                 return error("cannot read object %s", sha1_to_hex(sha1));
1170         if (type != OBJ_BLOB) {
1171                 free(buf);
1172                 return error("object %s is not a blob", sha1_to_hex(sha1));
1173         }
1174         strbuf_attach(dst, buf, size, size + 1);
1175         return 0;
1178 static int blob_unchanged(const unsigned char *o_sha,
1179                           const unsigned char *a_sha,
1180                           int renormalize, const char *path)
1182         struct strbuf o = STRBUF_INIT;
1183         struct strbuf a = STRBUF_INIT;
1184         int ret = 0; /* assume changed for safety */
1186         if (sha_eq(o_sha, a_sha))
1187                 return 1;
1188         if (!renormalize)
1189                 return 0;
1191         assert(o_sha && a_sha);
1192         if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1193                 goto error_return;
1194         /*
1195          * Note: binary | is used so that both renormalizations are
1196          * performed.  Comparison can be skipped if both files are
1197          * unchanged since their sha1s have already been compared.
1198          */
1199         if (renormalize_buffer(path, o.buf, o.len, &o) |
1200             renormalize_buffer(path, a.buf, o.len, &a))
1201                 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1203 error_return:
1204         strbuf_release(&o);
1205         strbuf_release(&a);
1206         return ret;
1209 static void handle_delete_modify(struct merge_options *o,
1210                                  const char *path,
1211                                  const char *new_path,
1212                                  unsigned char *a_sha, int a_mode,
1213                                  unsigned char *b_sha, int b_mode)
1215         if (!a_sha) {
1216                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1217                        "and modified in %s. Version %s of %s left in tree%s%s.",
1218                        path, o->branch1,
1219                        o->branch2, o->branch2, path,
1220                        path == new_path ? "" : " at ",
1221                        path == new_path ? "" : new_path);
1222                 update_file(o, 0, b_sha, b_mode, new_path);
1223         } else {
1224                 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1225                        "and modified in %s. Version %s of %s left in tree%s%s.",
1226                        path, o->branch2,
1227                        o->branch1, o->branch1, path,
1228                        path == new_path ? "" : " at ",
1229                        path == new_path ? "" : new_path);
1230                 update_file(o, 0, a_sha, a_mode, new_path);
1231         }
1234 static int merge_content(struct merge_options *o,
1235                          const char *path,
1236                          unsigned char *o_sha, int o_mode,
1237                          unsigned char *a_sha, int a_mode,
1238                          unsigned char *b_sha, int b_mode,
1239                          const char *df_rename_conflict_branch)
1241         const char *reason = "content";
1242         struct merge_file_info mfi;
1243         struct diff_filespec one, a, b;
1244         struct stat st;
1245         unsigned df_conflict_remains = 0;
1247         if (!o_sha) {
1248                 reason = "add/add";
1249                 o_sha = (unsigned char *)null_sha1;
1250         }
1251         one.path = a.path = b.path = (char *)path;
1252         hashcpy(one.sha1, o_sha);
1253         one.mode = o_mode;
1254         hashcpy(a.sha1, a_sha);
1255         a.mode = a_mode;
1256         hashcpy(b.sha1, b_sha);
1257         b.mode = b_mode;
1259         mfi = merge_file(o, &one, &a, &b, o->branch1, o->branch2);
1260         if (df_rename_conflict_branch &&
1261             lstat(path, &st) == 0 && S_ISDIR(st.st_mode)) {
1262                 df_conflict_remains = 1;
1263         }
1265         if (mfi.clean && !df_conflict_remains &&
1266             sha_eq(mfi.sha, a_sha) && mfi.mode == a.mode &&
1267             !o->call_depth && !lstat(path, &st)) {
1268                 output(o, 3, "Skipped %s (merged same as existing)", path);
1269                 add_cacheinfo(mfi.mode, mfi.sha, path,
1270                               0 /*stage*/, 1 /*refresh*/, 0 /*options*/);
1271                 return mfi.clean;
1272         } else
1273                 output(o, 2, "Auto-merging %s", path);
1275         if (!mfi.clean) {
1276                 if (S_ISGITLINK(mfi.mode))
1277                         reason = "submodule";
1278                 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1279                                 reason, path);
1280         }
1282         if (df_conflict_remains) {
1283                 const char *new_path;
1284                 update_file_flags(o, mfi.sha, mfi.mode, path,
1285                                   o->call_depth || mfi.clean, 0);
1286                 new_path = unique_path(o, path, df_rename_conflict_branch);
1287                 mfi.clean = 0;
1288                 output(o, 1, "Adding as %s instead", new_path);
1289                 update_file_flags(o, mfi.sha, mfi.mode, new_path, 0, 1);
1290         } else {
1291                 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1292         }
1293         return mfi.clean;
1297 /* Per entry merge function */
1298 static int process_entry(struct merge_options *o,
1299                          const char *path, struct stage_data *entry)
1301         /*
1302         printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1303         print_index_entry("\tpath: ", entry);
1304         */
1305         int clean_merge = 1;
1306         int normalize = o->renormalize;
1307         unsigned o_mode = entry->stages[1].mode;
1308         unsigned a_mode = entry->stages[2].mode;
1309         unsigned b_mode = entry->stages[3].mode;
1310         unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1311         unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1312         unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1314         if (entry->rename_df_conflict_info)
1315                 return 1; /* Such cases are handled elsewhere. */
1317         entry->processed = 1;
1318         if (o_sha && (!a_sha || !b_sha)) {
1319                 /* Case A: Deleted in one */
1320                 if ((!a_sha && !b_sha) ||
1321                     (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1322                     (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1323                         /* Deleted in both or deleted in one and
1324                          * unchanged in the other */
1325                         if (a_sha)
1326                                 output(o, 2, "Removing %s", path);
1327                         /* do not touch working file if it did not exist */
1328                         remove_file(o, 1, path, !a_sha);
1329                 } else if (string_list_has_string(&o->current_directory_set,
1330                                                   path)) {
1331                         entry->processed = 0;
1332                         return 1; /* Assume clean until processed */
1333                 } else {
1334                         /* Deleted in one and changed in the other */
1335                         clean_merge = 0;
1336                         handle_delete_modify(o, path, path,
1337                                              a_sha, a_mode, b_sha, b_mode);
1338                 }
1340         } else if ((!o_sha && a_sha && !b_sha) ||
1341                    (!o_sha && !a_sha && b_sha)) {
1342                 /* Case B: Added in one. */
1343                 unsigned mode;
1344                 const unsigned char *sha;
1346                 if (a_sha) {
1347                         mode = a_mode;
1348                         sha = a_sha;
1349                 } else {
1350                         mode = b_mode;
1351                         sha = b_sha;
1352                 }
1353                 if (string_list_has_string(&o->current_directory_set, path)) {
1354                         /* Handle D->F conflicts after all subfiles */
1355                         entry->processed = 0;
1356                         return 1; /* Assume clean until processed */
1357                 } else {
1358                         output(o, 2, "Adding %s", path);
1359                         update_file(o, 1, sha, mode, path);
1360                 }
1361         } else if (a_sha && b_sha) {
1362                 /* Case C: Added in both (check for same permissions) and */
1363                 /* case D: Modified in both, but differently. */
1364                 clean_merge = merge_content(o, path,
1365                                             o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1366                                             NULL);
1367         } else if (!o_sha && !a_sha && !b_sha) {
1368                 /*
1369                  * this entry was deleted altogether. a_mode == 0 means
1370                  * we had that path and want to actively remove it.
1371                  */
1372                 remove_file(o, 1, path, !a_mode);
1373         } else
1374                 die("Fatal merge failure, shouldn't happen.");
1376         return clean_merge;
1379 /*
1380  * Per entry merge function for D/F (and/or rename) conflicts.  In the
1381  * cases we can cleanly resolve D/F conflicts, process_entry() can
1382  * clean out all the files below the directory for us.  All D/F
1383  * conflict cases must be handled here at the end to make sure any
1384  * directories that can be cleaned out, are.
1385  *
1386  * Some rename conflicts may also be handled here that don't necessarily
1387  * involve D/F conflicts, since the code to handle them is generic enough
1388  * to handle those rename conflicts with or without D/F conflicts also
1389  * being involved.
1390  */
1391 static int process_df_entry(struct merge_options *o,
1392                             const char *path, struct stage_data *entry)
1394         int clean_merge = 1;
1395         unsigned o_mode = entry->stages[1].mode;
1396         unsigned a_mode = entry->stages[2].mode;
1397         unsigned b_mode = entry->stages[3].mode;
1398         unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1399         unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1400         unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1401         struct stat st;
1403         entry->processed = 1;
1404         if (entry->rename_df_conflict_info) {
1405                 struct rename_df_conflict_info *conflict_info = entry->rename_df_conflict_info;
1406                 char *src;
1407                 switch (conflict_info->rename_type) {
1408                 case RENAME_NORMAL:
1409                         clean_merge = merge_content(o, path,
1410                                                     o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1411                                                     conflict_info->branch1);
1412                         break;
1413                 case RENAME_DELETE:
1414                         clean_merge = 0;
1415                         conflict_rename_delete(o, conflict_info->pair1,
1416                                                conflict_info->branch1,
1417                                                conflict_info->branch2);
1418                         break;
1419                 case RENAME_ONE_FILE_TO_TWO:
1420                         src = conflict_info->pair1->one->path;
1421                         clean_merge = 0;
1422                         output(o, 1, "CONFLICT (rename/rename): "
1423                                "Rename \"%s\"->\"%s\" in branch \"%s\" "
1424                                "rename \"%s\"->\"%s\" in \"%s\"%s",
1425                                src, conflict_info->pair1->two->path, conflict_info->branch1,
1426                                src, conflict_info->pair2->two->path, conflict_info->branch2,
1427                                o->call_depth ? " (left unresolved)" : "");
1428                         if (o->call_depth) {
1429                                 remove_file_from_cache(src);
1430                                 update_file(o, 0, conflict_info->pair1->one->sha1,
1431                                             conflict_info->pair1->one->mode, src);
1432                         }
1433                         conflict_rename_rename_1to2(o, conflict_info->pair1,
1434                                                     conflict_info->branch1,
1435                                                     conflict_info->pair2,
1436                                                     conflict_info->branch2);
1437                         conflict_info->dst_entry2->processed = 1;
1438                         break;
1439                 default:
1440                         entry->processed = 0;
1441                         break;
1442                 }
1443         } else if (o_sha && (!a_sha || !b_sha)) {
1444                 /* Modify/delete; deleted side may have put a directory in the way */
1445                 const char *new_path = path;
1446                 if (lstat(path, &st) == 0 && S_ISDIR(st.st_mode))
1447                         new_path = unique_path(o, path, a_sha ? o->branch1 : o->branch2);
1448                 clean_merge = 0;
1449                 handle_delete_modify(o, path, new_path,
1450                                      a_sha, a_mode, b_sha, b_mode);
1451         } else if (!o_sha && !!a_sha != !!b_sha) {
1452                 /* directory -> (directory, file) */
1453                 const char *add_branch;
1454                 const char *other_branch;
1455                 unsigned mode;
1456                 const unsigned char *sha;
1457                 const char *conf;
1459                 if (a_sha) {
1460                         add_branch = o->branch1;
1461                         other_branch = o->branch2;
1462                         mode = a_mode;
1463                         sha = a_sha;
1464                         conf = "file/directory";
1465                 } else {
1466                         add_branch = o->branch2;
1467                         other_branch = o->branch1;
1468                         mode = b_mode;
1469                         sha = b_sha;
1470                         conf = "directory/file";
1471                 }
1472                 if (lstat(path, &st) == 0 && S_ISDIR(st.st_mode)) {
1473                         const char *new_path = unique_path(o, path, add_branch);
1474                         clean_merge = 0;
1475                         output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1476                                "Adding %s as %s",
1477                                conf, path, other_branch, path, new_path);
1478                         update_file(o, 0, sha, mode, new_path);
1479                 } else {
1480                         output(o, 2, "Adding %s", path);
1481                         update_file(o, 1, sha, mode, path);
1482                 }
1483         } else {
1484                 entry->processed = 0;
1485                 return 1; /* not handled; assume clean until processed */
1486         }
1488         return clean_merge;
1491 int merge_trees(struct merge_options *o,
1492                 struct tree *head,
1493                 struct tree *merge,
1494                 struct tree *common,
1495                 struct tree **result)
1497         int code, clean;
1499         if (o->subtree_shift) {
1500                 merge = shift_tree_object(head, merge, o->subtree_shift);
1501                 common = shift_tree_object(head, common, o->subtree_shift);
1502         }
1504         if (sha_eq(common->object.sha1, merge->object.sha1)) {
1505                 output(o, 0, "Already up-to-date!");
1506                 *result = head;
1507                 return 1;
1508         }
1510         code = git_merge_trees(o->call_depth, common, head, merge);
1512         if (code != 0) {
1513                 if (show(o, 4) || o->call_depth)
1514                         die("merging of trees %s and %s failed",
1515                             sha1_to_hex(head->object.sha1),
1516                             sha1_to_hex(merge->object.sha1));
1517                 else
1518                         exit(128);
1519         }
1521         if (unmerged_cache()) {
1522                 struct string_list *entries, *re_head, *re_merge;
1523                 int i;
1524                 string_list_clear(&o->current_file_set, 1);
1525                 string_list_clear(&o->current_directory_set, 1);
1526                 get_files_dirs(o, head);
1527                 get_files_dirs(o, merge);
1529                 entries = get_unmerged();
1530                 make_room_for_directories_of_df_conflicts(o, entries);
1531                 re_head  = get_renames(o, head, common, head, merge, entries);
1532                 re_merge = get_renames(o, merge, common, head, merge, entries);
1533                 clean = process_renames(o, re_head, re_merge);
1534                 for (i = 0; i < entries->nr; i++) {
1535                         const char *path = entries->items[i].string;
1536                         struct stage_data *e = entries->items[i].util;
1537                         if (!e->processed
1538                                 && !process_entry(o, path, e))
1539                                 clean = 0;
1540                 }
1541                 for (i = 0; i < entries->nr; i++) {
1542                         const char *path = entries->items[i].string;
1543                         struct stage_data *e = entries->items[i].util;
1544                         if (!e->processed
1545                                 && !process_df_entry(o, path, e))
1546                                 clean = 0;
1547                 }
1548                 for (i = 0; i < entries->nr; i++) {
1549                         struct stage_data *e = entries->items[i].util;
1550                         if (!e->processed)
1551                                 die("Unprocessed path??? %s",
1552                                     entries->items[i].string);
1553                 }
1555                 string_list_clear(re_merge, 0);
1556                 string_list_clear(re_head, 0);
1557                 string_list_clear(entries, 1);
1559         }
1560         else
1561                 clean = 1;
1563         if (o->call_depth)
1564                 *result = write_tree_from_memory(o);
1566         return clean;
1569 static struct commit_list *reverse_commit_list(struct commit_list *list)
1571         struct commit_list *next = NULL, *current, *backup;
1572         for (current = list; current; current = backup) {
1573                 backup = current->next;
1574                 current->next = next;
1575                 next = current;
1576         }
1577         return next;
1580 /*
1581  * Merge the commits h1 and h2, return the resulting virtual
1582  * commit object and a flag indicating the cleanness of the merge.
1583  */
1584 int merge_recursive(struct merge_options *o,
1585                     struct commit *h1,
1586                     struct commit *h2,
1587                     struct commit_list *ca,
1588                     struct commit **result)
1590         struct commit_list *iter;
1591         struct commit *merged_common_ancestors;
1592         struct tree *mrtree = mrtree;
1593         int clean;
1595         if (show(o, 4)) {
1596                 output(o, 4, "Merging:");
1597                 output_commit_title(o, h1);
1598                 output_commit_title(o, h2);
1599         }
1601         if (!ca) {
1602                 ca = get_merge_bases(h1, h2, 1);
1603                 ca = reverse_commit_list(ca);
1604         }
1606         if (show(o, 5)) {
1607                 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1608                 for (iter = ca; iter; iter = iter->next)
1609                         output_commit_title(o, iter->item);
1610         }
1612         merged_common_ancestors = pop_commit(&ca);
1613         if (merged_common_ancestors == NULL) {
1614                 /* if there is no common ancestor, make an empty tree */
1615                 struct tree *tree = xcalloc(1, sizeof(struct tree));
1617                 tree->object.parsed = 1;
1618                 tree->object.type = OBJ_TREE;
1619                 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1620                 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1621         }
1623         for (iter = ca; iter; iter = iter->next) {
1624                 const char *saved_b1, *saved_b2;
1625                 o->call_depth++;
1626                 /*
1627                  * When the merge fails, the result contains files
1628                  * with conflict markers. The cleanness flag is
1629                  * ignored, it was never actually used, as result of
1630                  * merge_trees has always overwritten it: the committed
1631                  * "conflicts" were already resolved.
1632                  */
1633                 discard_cache();
1634                 saved_b1 = o->branch1;
1635                 saved_b2 = o->branch2;
1636                 o->branch1 = "Temporary merge branch 1";
1637                 o->branch2 = "Temporary merge branch 2";
1638                 merge_recursive(o, merged_common_ancestors, iter->item,
1639                                 NULL, &merged_common_ancestors);
1640                 o->branch1 = saved_b1;
1641                 o->branch2 = saved_b2;
1642                 o->call_depth--;
1644                 if (!merged_common_ancestors)
1645                         die("merge returned no commit");
1646         }
1648         discard_cache();
1649         if (!o->call_depth)
1650                 read_cache();
1652         o->ancestor = "merged common ancestors";
1653         clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1654                             &mrtree);
1656         if (o->call_depth) {
1657                 *result = make_virtual_commit(mrtree, "merged tree");
1658                 commit_list_insert(h1, &(*result)->parents);
1659                 commit_list_insert(h2, &(*result)->parents->next);
1660         }
1661         flush_output(o);
1662         if (show(o, 2))
1663                 diff_warn_rename_limit("merge.renamelimit",
1664                                        o->needed_rename_limit, 0);
1665         return clean;
1668 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1670         struct object *object;
1672         object = deref_tag(parse_object(sha1), name, strlen(name));
1673         if (!object)
1674                 return NULL;
1675         if (object->type == OBJ_TREE)
1676                 return make_virtual_commit((struct tree*)object, name);
1677         if (object->type != OBJ_COMMIT)
1678                 return NULL;
1679         if (parse_commit((struct commit *)object))
1680                 return NULL;
1681         return (struct commit *)object;
1684 int merge_recursive_generic(struct merge_options *o,
1685                             const unsigned char *head,
1686                             const unsigned char *merge,
1687                             int num_base_list,
1688                             const unsigned char **base_list,
1689                             struct commit **result)
1691         int clean, index_fd;
1692         struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1693         struct commit *head_commit = get_ref(head, o->branch1);
1694         struct commit *next_commit = get_ref(merge, o->branch2);
1695         struct commit_list *ca = NULL;
1697         if (base_list) {
1698                 int i;
1699                 for (i = 0; i < num_base_list; ++i) {
1700                         struct commit *base;
1701                         if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1702                                 return error("Could not parse object '%s'",
1703                                         sha1_to_hex(base_list[i]));
1704                         commit_list_insert(base, &ca);
1705                 }
1706         }
1708         index_fd = hold_locked_index(lock, 1);
1709         clean = merge_recursive(o, head_commit, next_commit, ca,
1710                         result);
1711         if (active_cache_changed &&
1712                         (write_cache(index_fd, active_cache, active_nr) ||
1713                          commit_locked_index(lock)))
1714                 return error("Unable to write index.");
1716         return clean ? 0 : 1;
1719 static int merge_recursive_config(const char *var, const char *value, void *cb)
1721         struct merge_options *o = cb;
1722         if (!strcasecmp(var, "merge.verbosity")) {
1723                 o->verbosity = git_config_int(var, value);
1724                 return 0;
1725         }
1726         if (!strcasecmp(var, "diff.renamelimit")) {
1727                 o->diff_rename_limit = git_config_int(var, value);
1728                 return 0;
1729         }
1730         if (!strcasecmp(var, "merge.renamelimit")) {
1731                 o->merge_rename_limit = git_config_int(var, value);
1732                 return 0;
1733         }
1734         return git_xmerge_config(var, value, cb);
1737 void init_merge_options(struct merge_options *o)
1739         memset(o, 0, sizeof(struct merge_options));
1740         o->verbosity = 2;
1741         o->buffer_output = 1;
1742         o->diff_rename_limit = -1;
1743         o->merge_rename_limit = -1;
1744         o->renormalize = 0;
1745         git_config(merge_recursive_config, o);
1746         if (getenv("GIT_MERGE_VERBOSITY"))
1747                 o->verbosity =
1748                         strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1749         if (o->verbosity >= 5)
1750                 o->buffer_output = 0;
1751         strbuf_init(&o->obuf, 0);
1752         memset(&o->current_file_set, 0, sizeof(struct string_list));
1753         o->current_file_set.strdup_strings = 1;
1754         memset(&o->current_directory_set, 0, sizeof(struct string_list));
1755         o->current_directory_set.strdup_strings = 1;
1758 int parse_merge_opt(struct merge_options *o, const char *s)
1760         if (!s || !*s)
1761                 return -1;
1762         if (!strcmp(s, "ours"))
1763                 o->recursive_variant = MERGE_RECURSIVE_OURS;
1764         else if (!strcmp(s, "theirs"))
1765                 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
1766         else if (!strcmp(s, "subtree"))
1767                 o->subtree_shift = "";
1768         else if (!prefixcmp(s, "subtree="))
1769                 o->subtree_shift = s + strlen("subtree=");
1770         else if (!strcmp(s, "patience"))
1771                 o->xdl_opts |= XDF_PATIENCE_DIFF;
1772         else if (!strcmp(s, "ignore-space-change"))
1773                 o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1774         else if (!strcmp(s, "ignore-all-space"))
1775                 o->xdl_opts |= XDF_IGNORE_WHITESPACE;
1776         else if (!strcmp(s, "ignore-space-at-eol"))
1777                 o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
1778         else if (!strcmp(s, "renormalize"))
1779                 o->renormalize = 1;
1780         else if (!strcmp(s, "no-renormalize"))
1781                 o->renormalize = 0;
1782         else if (!prefixcmp(s, "rename-threshold=")) {
1783                 const char *score = s + strlen("rename-threshold=");
1784                 if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
1785                         return -1;
1786         }
1787         else
1788                 return -1;
1789         return 0;