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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)
102 {
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 }
120 }
122 static int show(struct merge_options *o, int v)
123 {
124 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
125 }
127 static void flush_output(struct merge_options *o)
128 {
129 if (o->obuf.len) {
130 fputs(o->obuf.buf, stdout);
131 strbuf_reset(&o->obuf);
132 }
133 }
135 __attribute__((format (printf, 3, 4)))
136 static void output(struct merge_options *o, int v, const char *fmt, ...)
137 {
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);
154 }
156 static void output_commit_title(struct merge_options *o, struct commit *commit)
157 {
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 }
175 }
177 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
178 const char *path, int stage, int refresh, int options)
179 {
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);
185 }
187 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
188 {
189 parse_tree(tree);
190 init_tree_desc(desc, tree->buffer, tree->size);
191 }
193 static int git_merge_trees(int index_only,
194 struct tree *common,
195 struct tree *head,
196 struct tree *merge)
197 {
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;
221 }
223 struct tree *write_tree_from_memory(struct merge_options *o)
224 {
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\n", 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;
250 }
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)
255 {
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);
271 }
273 static int get_files_dirs(struct merge_options *o, struct tree *tree)
274 {
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;
280 }
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)
289 {
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;
301 }
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)
308 {
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;
332 }
334 static int string_list_df_name_compare(const void *a, const void *b)
335 {
336 const struct string_list_item *one = a;
337 const struct string_list_item *two = b;
338 int onelen = strlen(one->string);
339 int twolen = strlen(two->string);
340 /*
341 * Here we only care that entries for D/F conflicts are
342 * adjacent, in particular with the file of the D/F conflict
343 * appearing before files below the corresponding directory.
344 * The order of the rest of the list is irrelevant for us.
345 *
346 * To achieve this, we sort with df_name_compare and provide
347 * the mode S_IFDIR so that D/F conflicts will sort correctly.
348 * We use the mode S_IFDIR for everything else for simplicity,
349 * since in other cases any changes in their order due to
350 * sorting cause no problems for us.
351 */
352 int cmp = df_name_compare(one->string, onelen, S_IFDIR,
353 two->string, twolen, S_IFDIR);
354 /*
355 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
356 * that 'foo' comes before 'foo/bar'.
357 */
358 if (cmp)
359 return cmp;
360 return onelen - twolen;
361 }
363 static void record_df_conflict_files(struct merge_options *o,
364 struct string_list *entries)
365 {
366 /* If there is a D/F conflict and the file for such a conflict
367 * currently exist in the working copy, we want to allow it to
368 * be removed to make room for the corresponding directory if
369 * needed. The files underneath the directories of such D/F
370 * conflicts will be handled in process_entry(), while the
371 * files of such D/F conflicts will be processed later in
372 * process_df_entry(). If the corresponding directory ends up
373 * being removed by the merge, then no additional work needs
374 * to be done by process_df_entry() for the conflicting file.
375 * If the directory needs to be written to the working copy,
376 * then the conflicting file will simply be removed (e.g. in
377 * make_room_for_path). If the directory is written to the
378 * working copy but the file also has a conflict that needs to
379 * be resolved, then process_df_entry() will reinstate the
380 * file with a new unique name.
381 */
382 const char *last_file = NULL;
383 int last_len = 0;
384 int i;
386 /*
387 * If we're merging merge-bases, we don't want to bother with
388 * any working directory changes.
389 */
390 if (o->call_depth)
391 return;
393 /* Ensure D/F conflicts are adjacent in the entries list. */
394 qsort(entries->items, entries->nr, sizeof(*entries->items),
395 string_list_df_name_compare);
397 string_list_clear(&o->df_conflict_file_set, 1);
398 for (i = 0; i < entries->nr; i++) {
399 const char *path = entries->items[i].string;
400 int len = strlen(path);
401 struct stage_data *e = entries->items[i].util;
403 /*
404 * Check if last_file & path correspond to a D/F conflict;
405 * i.e. whether path is last_file+'/'+<something>.
406 * If so, record that it's okay to remove last_file to make
407 * room for path and friends if needed.
408 */
409 if (last_file &&
410 len > last_len &&
411 memcmp(path, last_file, last_len) == 0 &&
412 path[last_len] == '/') {
413 output(o, 3, "Removing %s to make room for subdirectory; may re-add later.", last_file);
414 string_list_insert(&o->df_conflict_file_set, last_file);
415 }
417 /*
418 * Determine whether path could exist as a file in the
419 * working directory as a possible D/F conflict. This
420 * will only occur when it exists in stage 2 as a
421 * file.
422 */
423 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
424 last_file = path;
425 last_len = len;
426 } else {
427 last_file = NULL;
428 }
429 }
430 }
432 struct rename {
433 struct diff_filepair *pair;
434 struct stage_data *src_entry;
435 struct stage_data *dst_entry;
436 unsigned processed:1;
437 };
439 /*
440 * Get information of all renames which occurred between 'o_tree' and
441 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
442 * 'b_tree') to be able to associate the correct cache entries with
443 * the rename information. 'tree' is always equal to either a_tree or b_tree.
444 */
445 static struct string_list *get_renames(struct merge_options *o,
446 struct tree *tree,
447 struct tree *o_tree,
448 struct tree *a_tree,
449 struct tree *b_tree,
450 struct string_list *entries)
451 {
452 int i;
453 struct string_list *renames;
454 struct diff_options opts;
456 renames = xcalloc(1, sizeof(struct string_list));
457 diff_setup(&opts);
458 DIFF_OPT_SET(&opts, RECURSIVE);
459 opts.detect_rename = DIFF_DETECT_RENAME;
460 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
461 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
462 1000;
463 opts.rename_score = o->rename_score;
464 opts.show_rename_progress = o->show_rename_progress;
465 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
466 if (diff_setup_done(&opts) < 0)
467 die("diff setup failed");
468 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
469 diffcore_std(&opts);
470 if (opts.needed_rename_limit > o->needed_rename_limit)
471 o->needed_rename_limit = opts.needed_rename_limit;
472 for (i = 0; i < diff_queued_diff.nr; ++i) {
473 struct string_list_item *item;
474 struct rename *re;
475 struct diff_filepair *pair = diff_queued_diff.queue[i];
476 if (pair->status != 'R') {
477 diff_free_filepair(pair);
478 continue;
479 }
480 re = xmalloc(sizeof(*re));
481 re->processed = 0;
482 re->pair = pair;
483 item = string_list_lookup(entries, re->pair->one->path);
484 if (!item)
485 re->src_entry = insert_stage_data(re->pair->one->path,
486 o_tree, a_tree, b_tree, entries);
487 else
488 re->src_entry = item->util;
490 item = string_list_lookup(entries, re->pair->two->path);
491 if (!item)
492 re->dst_entry = insert_stage_data(re->pair->two->path,
493 o_tree, a_tree, b_tree, entries);
494 else
495 re->dst_entry = item->util;
496 item = string_list_insert(renames, pair->one->path);
497 item->util = re;
498 }
499 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
500 diff_queued_diff.nr = 0;
501 diff_flush(&opts);
502 return renames;
503 }
505 static int update_stages(const char *path, const struct diff_filespec *o,
506 const struct diff_filespec *a,
507 const struct diff_filespec *b)
508 {
509 int clear = 1;
510 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
511 if (clear)
512 if (remove_file_from_cache(path))
513 return -1;
514 if (o)
515 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
516 return -1;
517 if (a)
518 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
519 return -1;
520 if (b)
521 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
522 return -1;
523 return 0;
524 }
526 static int update_stages_and_entry(const char *path,
527 struct stage_data *entry,
528 struct diff_filespec *o,
529 struct diff_filespec *a,
530 struct diff_filespec *b,
531 int clear)
532 {
533 int options;
535 entry->processed = 0;
536 entry->stages[1].mode = o->mode;
537 entry->stages[2].mode = a->mode;
538 entry->stages[3].mode = b->mode;
539 hashcpy(entry->stages[1].sha, o->sha1);
540 hashcpy(entry->stages[2].sha, a->sha1);
541 hashcpy(entry->stages[3].sha, b->sha1);
542 return update_stages(path, o, a, b);
543 }
545 static int remove_file(struct merge_options *o, int clean,
546 const char *path, int no_wd)
547 {
548 int update_cache = o->call_depth || clean;
549 int update_working_directory = !o->call_depth && !no_wd;
551 if (update_cache) {
552 if (remove_file_from_cache(path))
553 return -1;
554 }
555 if (update_working_directory) {
556 if (remove_path(path))
557 return -1;
558 }
559 return 0;
560 }
562 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
563 {
564 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
565 int suffix = 0;
566 struct stat st;
567 char *p = newpath + strlen(path);
568 strcpy(newpath, path);
569 *(p++) = '~';
570 strcpy(p, branch);
571 for (; *p; ++p)
572 if ('/' == *p)
573 *p = '_';
574 while (string_list_has_string(&o->current_file_set, newpath) ||
575 string_list_has_string(&o->current_directory_set, newpath) ||
576 lstat(newpath, &st) == 0)
577 sprintf(p, "_%d", suffix++);
579 string_list_insert(&o->current_file_set, newpath);
580 return newpath;
581 }
583 static void flush_buffer(int fd, const char *buf, unsigned long size)
584 {
585 while (size > 0) {
586 long ret = write_in_full(fd, buf, size);
587 if (ret < 0) {
588 /* Ignore epipe */
589 if (errno == EPIPE)
590 break;
591 die_errno("merge-recursive");
592 } else if (!ret) {
593 die("merge-recursive: disk full?");
594 }
595 size -= ret;
596 buf += ret;
597 }
598 }
600 static int dir_in_way(const char *path, int check_working_copy)
601 {
602 int pos, pathlen = strlen(path);
603 char *dirpath = xmalloc(pathlen + 2);
604 struct stat st;
606 strcpy(dirpath, path);
607 dirpath[pathlen] = '/';
608 dirpath[pathlen+1] = '\0';
610 pos = cache_name_pos(dirpath, pathlen+1);
612 if (pos < 0)
613 pos = -1 - pos;
614 if (pos < active_nr &&
615 !strncmp(dirpath, active_cache[pos]->name, pathlen+1)) {
616 free(dirpath);
617 return 1;
618 }
620 free(dirpath);
621 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode);
622 }
624 static int was_tracked(const char *path)
625 {
626 int pos = cache_name_pos(path, strlen(path));
628 if (pos < 0)
629 pos = -1 - pos;
630 while (pos < active_nr &&
631 !strcmp(path, active_cache[pos]->name)) {
632 /*
633 * If stage #0, it is definitely tracked.
634 * If it has stage #2 then it was tracked
635 * before this merge started. All other
636 * cases the path was not tracked.
637 */
638 switch (ce_stage(active_cache[pos])) {
639 case 0:
640 case 2:
641 return 1;
642 }
643 pos++;
644 }
645 return 0;
646 }
648 static int would_lose_untracked(const char *path)
649 {
650 return !was_tracked(path) && file_exists(path);
651 }
653 static int make_room_for_path(const char *path)
654 {
655 int status;
656 const char *msg = "failed to create path '%s'%s";
658 status = safe_create_leading_directories_const(path);
659 if (status) {
660 if (status == -3) {
661 /* something else exists */
662 error(msg, path, ": perhaps a D/F conflict?");
663 return -1;
664 }
665 die(msg, path, "");
666 }
668 /*
669 * Do not unlink a file in the work tree if we are not
670 * tracking it.
671 */
672 if (would_lose_untracked(path))
673 return error("refusing to lose untracked file at '%s'",
674 path);
676 /* Successful unlink is good.. */
677 if (!unlink(path))
678 return 0;
679 /* .. and so is no existing file */
680 if (errno == ENOENT)
681 return 0;
682 /* .. but not some other error (who really cares what?) */
683 return error(msg, path, ": perhaps a D/F conflict?");
684 }
686 static void update_file_flags(struct merge_options *o,
687 const unsigned char *sha,
688 unsigned mode,
689 const char *path,
690 int update_cache,
691 int update_wd)
692 {
693 if (o->call_depth)
694 update_wd = 0;
696 if (update_wd) {
697 enum object_type type;
698 void *buf;
699 unsigned long size;
701 if (S_ISGITLINK(mode)) {
702 /*
703 * We may later decide to recursively descend into
704 * the submodule directory and update its index
705 * and/or work tree, but we do not do that now.
706 */
707 update_wd = 0;
708 goto update_index;
709 }
711 buf = read_sha1_file(sha, &type, &size);
712 if (!buf)
713 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
714 if (type != OBJ_BLOB)
715 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
716 if (S_ISREG(mode)) {
717 struct strbuf strbuf = STRBUF_INIT;
718 if (convert_to_working_tree(path, buf, size, &strbuf)) {
719 free(buf);
720 size = strbuf.len;
721 buf = strbuf_detach(&strbuf, NULL);
722 }
723 }
725 if (make_room_for_path(path) < 0) {
726 update_wd = 0;
727 free(buf);
728 goto update_index;
729 }
730 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
731 int fd;
732 if (mode & 0100)
733 mode = 0777;
734 else
735 mode = 0666;
736 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
737 if (fd < 0)
738 die_errno("failed to open '%s'", path);
739 flush_buffer(fd, buf, size);
740 close(fd);
741 } else if (S_ISLNK(mode)) {
742 char *lnk = xmemdupz(buf, size);
743 safe_create_leading_directories_const(path);
744 unlink(path);
745 if (symlink(lnk, path))
746 die_errno("failed to symlink '%s'", path);
747 free(lnk);
748 } else
749 die("do not know what to do with %06o %s '%s'",
750 mode, sha1_to_hex(sha), path);
751 free(buf);
752 }
753 update_index:
754 if (update_cache)
755 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
756 }
758 static void update_file(struct merge_options *o,
759 int clean,
760 const unsigned char *sha,
761 unsigned mode,
762 const char *path)
763 {
764 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
765 }
767 /* Low level file merging, update and removal */
769 struct merge_file_info {
770 unsigned char sha[20];
771 unsigned mode;
772 unsigned clean:1,
773 merge:1;
774 };
776 static int merge_3way(struct merge_options *o,
777 mmbuffer_t *result_buf,
778 const struct diff_filespec *one,
779 const struct diff_filespec *a,
780 const struct diff_filespec *b,
781 const char *branch1,
782 const char *branch2)
783 {
784 mmfile_t orig, src1, src2;
785 struct ll_merge_options ll_opts = {0};
786 char *base_name, *name1, *name2;
787 int merge_status;
789 ll_opts.renormalize = o->renormalize;
790 ll_opts.xdl_opts = o->xdl_opts;
792 if (o->call_depth) {
793 ll_opts.virtual_ancestor = 1;
794 ll_opts.variant = 0;
795 } else {
796 switch (o->recursive_variant) {
797 case MERGE_RECURSIVE_OURS:
798 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
799 break;
800 case MERGE_RECURSIVE_THEIRS:
801 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
802 break;
803 default:
804 ll_opts.variant = 0;
805 break;
806 }
807 }
809 if (strcmp(a->path, b->path) ||
810 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
811 base_name = o->ancestor == NULL ? NULL :
812 xstrdup(mkpath("%s:%s", o->ancestor, one->path));
813 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
814 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
815 } else {
816 base_name = o->ancestor == NULL ? NULL :
817 xstrdup(mkpath("%s", o->ancestor));
818 name1 = xstrdup(mkpath("%s", branch1));
819 name2 = xstrdup(mkpath("%s", branch2));
820 }
822 read_mmblob(&orig, one->sha1);
823 read_mmblob(&src1, a->sha1);
824 read_mmblob(&src2, b->sha1);
826 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
827 &src1, name1, &src2, name2, &ll_opts);
829 free(name1);
830 free(name2);
831 free(orig.ptr);
832 free(src1.ptr);
833 free(src2.ptr);
834 return merge_status;
835 }
837 static struct merge_file_info merge_file(struct merge_options *o,
838 const struct diff_filespec *one,
839 const struct diff_filespec *a,
840 const struct diff_filespec *b,
841 const char *branch1,
842 const char *branch2)
843 {
844 struct merge_file_info result;
845 result.merge = 0;
846 result.clean = 1;
848 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
849 result.clean = 0;
850 if (S_ISREG(a->mode)) {
851 result.mode = a->mode;
852 hashcpy(result.sha, a->sha1);
853 } else {
854 result.mode = b->mode;
855 hashcpy(result.sha, b->sha1);
856 }
857 } else {
858 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
859 result.merge = 1;
861 /*
862 * Merge modes
863 */
864 if (a->mode == b->mode || a->mode == one->mode)
865 result.mode = b->mode;
866 else {
867 result.mode = a->mode;
868 if (b->mode != one->mode) {
869 result.clean = 0;
870 result.merge = 1;
871 }
872 }
874 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
875 hashcpy(result.sha, b->sha1);
876 else if (sha_eq(b->sha1, one->sha1))
877 hashcpy(result.sha, a->sha1);
878 else if (S_ISREG(a->mode)) {
879 mmbuffer_t result_buf;
880 int merge_status;
882 merge_status = merge_3way(o, &result_buf, one, a, b,
883 branch1, branch2);
885 if ((merge_status < 0) || !result_buf.ptr)
886 die("Failed to execute internal merge");
888 if (write_sha1_file(result_buf.ptr, result_buf.size,
889 blob_type, result.sha))
890 die("Unable to add %s to database",
891 a->path);
893 free(result_buf.ptr);
894 result.clean = (merge_status == 0);
895 } else if (S_ISGITLINK(a->mode)) {
896 result.clean = merge_submodule(result.sha, one->path, one->sha1,
897 a->sha1, b->sha1);
898 } else if (S_ISLNK(a->mode)) {
899 hashcpy(result.sha, a->sha1);
901 if (!sha_eq(a->sha1, b->sha1))
902 result.clean = 0;
903 } else {
904 die("unsupported object type in the tree");
905 }
906 }
908 return result;
909 }
911 static void conflict_rename_delete(struct merge_options *o,
912 struct diff_filepair *pair,
913 const char *rename_branch,
914 const char *other_branch)
915 {
916 char *dest_name = pair->two->path;
917 int df_conflict = 0;
919 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
920 "and deleted in %s",
921 pair->one->path, pair->two->path, rename_branch,
922 other_branch);
923 if (!o->call_depth)
924 update_stages(dest_name, NULL,
925 rename_branch == o->branch1 ? pair->two : NULL,
926 rename_branch == o->branch1 ? NULL : pair->two);
927 if (dir_in_way(dest_name, !o->call_depth)) {
928 dest_name = unique_path(o, dest_name, rename_branch);
929 df_conflict = 1;
930 }
931 update_file(o, 0, pair->two->sha1, pair->two->mode, dest_name);
932 if (df_conflict)
933 free(dest_name);
934 }
936 static void conflict_rename_rename_1to2(struct merge_options *o,
937 struct diff_filepair *pair1,
938 const char *branch1,
939 struct diff_filepair *pair2,
940 const char *branch2)
941 {
942 /* One file was renamed in both branches, but to different names. */
943 char *del[2];
944 int delp = 0;
945 const char *ren1_dst = pair1->two->path;
946 const char *ren2_dst = pair2->two->path;
947 const char *dst_name1 = ren1_dst;
948 const char *dst_name2 = ren2_dst;
949 if (dir_in_way(ren1_dst, !o->call_depth)) {
950 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
951 output(o, 1, "%s is a directory in %s adding as %s instead",
952 ren1_dst, branch2, dst_name1);
953 }
954 if (dir_in_way(ren2_dst, !o->call_depth)) {
955 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
956 output(o, 1, "%s is a directory in %s adding as %s instead",
957 ren2_dst, branch1, dst_name2);
958 }
959 if (o->call_depth) {
960 remove_file_from_cache(dst_name1);
961 remove_file_from_cache(dst_name2);
962 /*
963 * Uncomment to leave the conflicting names in the resulting tree
964 *
965 * update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1);
966 * update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2);
967 */
968 } else {
969 update_stages(ren1_dst, NULL, pair1->two, NULL);
970 update_stages(ren2_dst, NULL, NULL, pair2->two);
972 update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1);
973 update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2);
974 }
975 while (delp--)
976 free(del[delp]);
977 }
979 static void conflict_rename_rename_2to1(struct merge_options *o,
980 struct rename *ren1,
981 const char *branch1,
982 struct rename *ren2,
983 const char *branch2)
984 {
985 /* Two files were renamed to the same thing. */
986 char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
987 char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
988 output(o, 1, "Renaming %s to %s and %s to %s instead",
989 ren1->pair->one->path, new_path1,
990 ren2->pair->one->path, new_path2);
991 remove_file(o, 0, ren1->pair->two->path, 0);
992 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
993 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
994 free(new_path2);
995 free(new_path1);
996 }
998 static int process_renames(struct merge_options *o,
999 struct string_list *a_renames,
1000 struct string_list *b_renames)
1001 {
1002 int clean_merge = 1, i, j;
1003 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
1004 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
1005 const struct rename *sre;
1007 for (i = 0; i < a_renames->nr; i++) {
1008 sre = a_renames->items[i].util;
1009 string_list_insert(&a_by_dst, sre->pair->two->path)->util
1010 = sre->dst_entry;
1011 }
1012 for (i = 0; i < b_renames->nr; i++) {
1013 sre = b_renames->items[i].util;
1014 string_list_insert(&b_by_dst, sre->pair->two->path)->util
1015 = sre->dst_entry;
1016 }
1018 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1019 struct string_list *renames1, *renames2Dst;
1020 struct rename *ren1 = NULL, *ren2 = NULL;
1021 const char *branch1, *branch2;
1022 const char *ren1_src, *ren1_dst;
1024 if (i >= a_renames->nr) {
1025 ren2 = b_renames->items[j++].util;
1026 } else if (j >= b_renames->nr) {
1027 ren1 = a_renames->items[i++].util;
1028 } else {
1029 int compare = strcmp(a_renames->items[i].string,
1030 b_renames->items[j].string);
1031 if (compare <= 0)
1032 ren1 = a_renames->items[i++].util;
1033 if (compare >= 0)
1034 ren2 = b_renames->items[j++].util;
1035 }
1037 /* TODO: refactor, so that 1/2 are not needed */
1038 if (ren1) {
1039 renames1 = a_renames;
1040 renames2Dst = &b_by_dst;
1041 branch1 = o->branch1;
1042 branch2 = o->branch2;
1043 } else {
1044 struct rename *tmp;
1045 renames1 = b_renames;
1046 renames2Dst = &a_by_dst;
1047 branch1 = o->branch2;
1048 branch2 = o->branch1;
1049 tmp = ren2;
1050 ren2 = ren1;
1051 ren1 = tmp;
1052 }
1054 ren1->dst_entry->processed = 1;
1055 ren1->src_entry->processed = 1;
1057 if (ren1->processed)
1058 continue;
1059 ren1->processed = 1;
1061 ren1_src = ren1->pair->one->path;
1062 ren1_dst = ren1->pair->two->path;
1064 if (ren2) {
1065 const char *ren2_src = ren2->pair->one->path;
1066 const char *ren2_dst = ren2->pair->two->path;
1067 /* Renamed in 1 and renamed in 2 */
1068 if (strcmp(ren1_src, ren2_src) != 0)
1069 die("ren1.src != ren2.src");
1070 ren2->dst_entry->processed = 1;
1071 ren2->processed = 1;
1072 if (strcmp(ren1_dst, ren2_dst) != 0) {
1073 setup_rename_df_conflict_info(RENAME_ONE_FILE_TO_TWO,
1074 ren1->pair,
1075 ren2->pair,
1076 branch1,
1077 branch2,
1078 ren1->dst_entry,
1079 ren2->dst_entry);
1080 } else {
1081 remove_file(o, 1, ren1_src, 1);
1082 update_stages_and_entry(ren1_dst,
1083 ren1->dst_entry,
1084 ren1->pair->one,
1085 ren1->pair->two,
1086 ren2->pair->two,
1087 1 /* clear */);
1088 }
1089 } else {
1090 /* Renamed in 1, maybe changed in 2 */
1091 struct string_list_item *item;
1092 /* we only use sha1 and mode of these */
1093 struct diff_filespec src_other, dst_other;
1094 int try_merge;
1096 /*
1097 * unpack_trees loads entries from common-commit
1098 * into stage 1, from head-commit into stage 2, and
1099 * from merge-commit into stage 3. We keep track
1100 * of which side corresponds to the rename.
1101 */
1102 int renamed_stage = a_renames == renames1 ? 2 : 3;
1103 int other_stage = a_renames == renames1 ? 3 : 2;
1105 remove_file(o, 1, ren1_src, o->call_depth || renamed_stage == 2);
1107 hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha);
1108 src_other.mode = ren1->src_entry->stages[other_stage].mode;
1109 hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha);
1110 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
1111 try_merge = 0;
1113 if (sha_eq(src_other.sha1, null_sha1)) {
1114 if (dir_in_way(ren1_dst, 0 /*check_wc*/)) {
1115 ren1->dst_entry->processed = 0;
1116 setup_rename_df_conflict_info(RENAME_DELETE,
1117 ren1->pair,
1118 NULL,
1119 branch1,
1120 branch2,
1121 ren1->dst_entry,
1122 NULL);
1123 } else {
1124 clean_merge = 0;
1125 conflict_rename_delete(o, ren1->pair, branch1, branch2);
1126 }
1127 } else if ((dst_other.mode == ren1->pair->two->mode) &&
1128 sha_eq(dst_other.sha1, ren1->pair->two->sha1)) {
1129 /* Added file on the other side
1130 identical to the file being
1131 renamed: clean merge */
1132 update_file(o, 1, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
1133 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1134 clean_merge = 0;
1135 try_merge = 1;
1136 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
1137 "%s added in %s",
1138 ren1_src, ren1_dst, branch1,
1139 ren1_dst, branch2);
1140 if (o->call_depth) {
1141 struct merge_file_info mfi;
1142 struct diff_filespec one, a, b;
1144 one.path = a.path = b.path =
1145 (char *)ren1_dst;
1146 hashcpy(one.sha1, null_sha1);
1147 one.mode = 0;
1148 hashcpy(a.sha1, ren1->pair->two->sha1);
1149 a.mode = ren1->pair->two->mode;
1150 hashcpy(b.sha1, dst_other.sha1);
1151 b.mode = dst_other.mode;
1152 mfi = merge_file(o, &one, &a, &b,
1153 branch1,
1154 branch2);
1155 output(o, 1, "Adding merged %s", ren1_dst);
1156 update_file(o, 0,
1157 mfi.sha,
1158 mfi.mode,
1159 ren1_dst);
1160 try_merge = 0;
1161 } else {
1162 char *new_path = unique_path(o, ren1_dst, branch2);
1163 output(o, 1, "Adding as %s instead", new_path);
1164 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
1165 free(new_path);
1166 }
1167 } else if ((item = string_list_lookup(renames2Dst, ren1_dst))) {
1168 ren2 = item->util;
1169 clean_merge = 0;
1170 ren2->processed = 1;
1171 output(o, 1, "CONFLICT (rename/rename): "
1172 "Rename %s->%s in %s. "
1173 "Rename %s->%s in %s",
1174 ren1_src, ren1_dst, branch1,
1175 ren2->pair->one->path, ren2->pair->two->path, branch2);
1176 conflict_rename_rename_2to1(o, ren1, branch1, ren2, branch2);
1177 } else
1178 try_merge = 1;
1180 if (try_merge) {
1181 struct diff_filespec *one, *a, *b;
1182 src_other.path = (char *)ren1_src;
1184 one = ren1->pair->one;
1185 if (a_renames == renames1) {
1186 a = ren1->pair->two;
1187 b = &src_other;
1188 } else {
1189 b = ren1->pair->two;
1190 a = &src_other;
1191 }
1192 update_stages_and_entry(ren1_dst, ren1->dst_entry, one, a, b, 1);
1193 if (dir_in_way(ren1_dst, 0 /*check_wc*/)) {
1194 setup_rename_df_conflict_info(RENAME_NORMAL,
1195 ren1->pair,
1196 NULL,
1197 branch1,
1198 NULL,
1199 ren1->dst_entry,
1200 NULL);
1201 }
1202 }
1203 }
1204 }
1205 string_list_clear(&a_by_dst, 0);
1206 string_list_clear(&b_by_dst, 0);
1208 return clean_merge;
1209 }
1211 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1212 {
1213 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1214 }
1216 static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst)
1217 {
1218 void *buf;
1219 enum object_type type;
1220 unsigned long size;
1221 buf = read_sha1_file(sha1, &type, &size);
1222 if (!buf)
1223 return error("cannot read object %s", sha1_to_hex(sha1));
1224 if (type != OBJ_BLOB) {
1225 free(buf);
1226 return error("object %s is not a blob", sha1_to_hex(sha1));
1227 }
1228 strbuf_attach(dst, buf, size, size + 1);
1229 return 0;
1230 }
1232 static int blob_unchanged(const unsigned char *o_sha,
1233 const unsigned char *a_sha,
1234 int renormalize, const char *path)
1235 {
1236 struct strbuf o = STRBUF_INIT;
1237 struct strbuf a = STRBUF_INIT;
1238 int ret = 0; /* assume changed for safety */
1240 if (sha_eq(o_sha, a_sha))
1241 return 1;
1242 if (!renormalize)
1243 return 0;
1245 assert(o_sha && a_sha);
1246 if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &a))
1247 goto error_return;
1248 /*
1249 * Note: binary | is used so that both renormalizations are
1250 * performed. Comparison can be skipped if both files are
1251 * unchanged since their sha1s have already been compared.
1252 */
1253 if (renormalize_buffer(path, o.buf, o.len, &o) |
1254 renormalize_buffer(path, a.buf, o.len, &a))
1255 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
1257 error_return:
1258 strbuf_release(&o);
1259 strbuf_release(&a);
1260 return ret;
1261 }
1263 static void handle_delete_modify(struct merge_options *o,
1264 const char *path,
1265 const char *new_path,
1266 unsigned char *a_sha, int a_mode,
1267 unsigned char *b_sha, int b_mode)
1268 {
1269 if (!a_sha) {
1270 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1271 "and modified in %s. Version %s of %s left in tree%s%s.",
1272 path, o->branch1,
1273 o->branch2, o->branch2, path,
1274 path == new_path ? "" : " at ",
1275 path == new_path ? "" : new_path);
1276 update_file(o, 0, b_sha, b_mode, new_path);
1277 } else {
1278 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1279 "and modified in %s. Version %s of %s left in tree%s%s.",
1280 path, o->branch2,
1281 o->branch1, o->branch1, path,
1282 path == new_path ? "" : " at ",
1283 path == new_path ? "" : new_path);
1284 update_file(o, 0, a_sha, a_mode, new_path);
1285 }
1286 }
1288 static int merge_content(struct merge_options *o,
1289 const char *path,
1290 unsigned char *o_sha, int o_mode,
1291 unsigned char *a_sha, int a_mode,
1292 unsigned char *b_sha, int b_mode,
1293 const char *df_rename_conflict_branch)
1294 {
1295 const char *reason = "content";
1296 struct merge_file_info mfi;
1297 struct diff_filespec one, a, b;
1298 unsigned df_conflict_remains = 0;
1300 if (!o_sha) {
1301 reason = "add/add";
1302 o_sha = (unsigned char *)null_sha1;
1303 }
1304 one.path = a.path = b.path = (char *)path;
1305 hashcpy(one.sha1, o_sha);
1306 one.mode = o_mode;
1307 hashcpy(a.sha1, a_sha);
1308 a.mode = a_mode;
1309 hashcpy(b.sha1, b_sha);
1310 b.mode = b_mode;
1312 mfi = merge_file(o, &one, &a, &b, o->branch1, o->branch2);
1313 if (df_rename_conflict_branch &&
1314 dir_in_way(path, !o->call_depth)) {
1315 df_conflict_remains = 1;
1316 }
1318 if (mfi.clean && !df_conflict_remains &&
1319 sha_eq(mfi.sha, a_sha) && mfi.mode == a.mode)
1320 output(o, 3, "Skipped %s (merged same as existing)", path);
1321 else
1322 output(o, 2, "Auto-merging %s", path);
1324 if (!mfi.clean) {
1325 if (S_ISGITLINK(mfi.mode))
1326 reason = "submodule";
1327 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1328 reason, path);
1329 }
1331 if (df_conflict_remains) {
1332 char *new_path;
1333 update_file_flags(o, mfi.sha, mfi.mode, path,
1334 o->call_depth || mfi.clean, 0);
1335 new_path = unique_path(o, path, df_rename_conflict_branch);
1336 mfi.clean = 0;
1337 output(o, 1, "Adding as %s instead", new_path);
1338 update_file_flags(o, mfi.sha, mfi.mode, new_path, 0, 1);
1339 free(new_path);
1340 } else {
1341 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1342 }
1343 return mfi.clean;
1345 }
1347 /* Per entry merge function */
1348 static int process_entry(struct merge_options *o,
1349 const char *path, struct stage_data *entry)
1350 {
1351 /*
1352 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1353 print_index_entry("\tpath: ", entry);
1354 */
1355 int clean_merge = 1;
1356 int normalize = o->renormalize;
1357 unsigned o_mode = entry->stages[1].mode;
1358 unsigned a_mode = entry->stages[2].mode;
1359 unsigned b_mode = entry->stages[3].mode;
1360 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1361 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1362 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1364 if (entry->rename_df_conflict_info)
1365 return 1; /* Such cases are handled elsewhere. */
1367 entry->processed = 1;
1368 if (o_sha && (!a_sha || !b_sha)) {
1369 /* Case A: Deleted in one */
1370 if ((!a_sha && !b_sha) ||
1371 (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) ||
1372 (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) {
1373 /* Deleted in both or deleted in one and
1374 * unchanged in the other */
1375 if (a_sha)
1376 output(o, 2, "Removing %s", path);
1377 /* do not touch working file if it did not exist */
1378 remove_file(o, 1, path, !a_sha);
1379 } else if (dir_in_way(path, 0 /*check_wc*/)) {
1380 entry->processed = 0;
1381 return 1; /* Assume clean until processed */
1382 } else {
1383 /* Deleted in one and changed in the other */
1384 clean_merge = 0;
1385 handle_delete_modify(o, path, path,
1386 a_sha, a_mode, b_sha, b_mode);
1387 }
1389 } else if ((!o_sha && a_sha && !b_sha) ||
1390 (!o_sha && !a_sha && b_sha)) {
1391 /* Case B: Added in one. */
1392 unsigned mode;
1393 const unsigned char *sha;
1395 if (a_sha) {
1396 mode = a_mode;
1397 sha = a_sha;
1398 } else {
1399 mode = b_mode;
1400 sha = b_sha;
1401 }
1402 if (dir_in_way(path, 0 /*check_wc*/)) {
1403 /* Handle D->F conflicts after all subfiles */
1404 entry->processed = 0;
1405 return 1; /* Assume clean until processed */
1406 } else {
1407 output(o, 2, "Adding %s", path);
1408 update_file(o, 1, sha, mode, path);
1409 }
1410 } else if (a_sha && b_sha) {
1411 /* Case C: Added in both (check for same permissions) and */
1412 /* case D: Modified in both, but differently. */
1413 clean_merge = merge_content(o, path,
1414 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1415 NULL);
1416 } else if (!o_sha && !a_sha && !b_sha) {
1417 /*
1418 * this entry was deleted altogether. a_mode == 0 means
1419 * we had that path and want to actively remove it.
1420 */
1421 remove_file(o, 1, path, !a_mode);
1422 } else
1423 die("Fatal merge failure, shouldn't happen.");
1425 return clean_merge;
1426 }
1428 /*
1429 * Per entry merge function for D/F (and/or rename) conflicts. In the
1430 * cases we can cleanly resolve D/F conflicts, process_entry() can
1431 * clean out all the files below the directory for us. All D/F
1432 * conflict cases must be handled here at the end to make sure any
1433 * directories that can be cleaned out, are.
1434 *
1435 * Some rename conflicts may also be handled here that don't necessarily
1436 * involve D/F conflicts, since the code to handle them is generic enough
1437 * to handle those rename conflicts with or without D/F conflicts also
1438 * being involved.
1439 */
1440 static int process_df_entry(struct merge_options *o,
1441 const char *path, struct stage_data *entry)
1442 {
1443 int clean_merge = 1;
1444 unsigned o_mode = entry->stages[1].mode;
1445 unsigned a_mode = entry->stages[2].mode;
1446 unsigned b_mode = entry->stages[3].mode;
1447 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1448 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1449 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1451 entry->processed = 1;
1452 if (entry->rename_df_conflict_info) {
1453 struct rename_df_conflict_info *conflict_info = entry->rename_df_conflict_info;
1454 char *src;
1455 switch (conflict_info->rename_type) {
1456 case RENAME_NORMAL:
1457 clean_merge = merge_content(o, path,
1458 o_sha, o_mode, a_sha, a_mode, b_sha, b_mode,
1459 conflict_info->branch1);
1460 break;
1461 case RENAME_DELETE:
1462 clean_merge = 0;
1463 conflict_rename_delete(o, conflict_info->pair1,
1464 conflict_info->branch1,
1465 conflict_info->branch2);
1466 break;
1467 case RENAME_ONE_FILE_TO_TWO:
1468 src = conflict_info->pair1->one->path;
1469 clean_merge = 0;
1470 output(o, 1, "CONFLICT (rename/rename): "
1471 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1472 "rename \"%s\"->\"%s\" in \"%s\"%s",
1473 src, conflict_info->pair1->two->path, conflict_info->branch1,
1474 src, conflict_info->pair2->two->path, conflict_info->branch2,
1475 o->call_depth ? " (left unresolved)" : "");
1476 if (o->call_depth) {
1477 remove_file_from_cache(src);
1478 update_file(o, 0, conflict_info->pair1->one->sha1,
1479 conflict_info->pair1->one->mode, src);
1480 }
1481 conflict_rename_rename_1to2(o, conflict_info->pair1,
1482 conflict_info->branch1,
1483 conflict_info->pair2,
1484 conflict_info->branch2);
1485 conflict_info->dst_entry2->processed = 1;
1486 break;
1487 default:
1488 entry->processed = 0;
1489 break;
1490 }
1491 } else if (o_sha && (!a_sha || !b_sha)) {
1492 /* Modify/delete; deleted side may have put a directory in the way */
1493 char *renamed = NULL;
1494 if (dir_in_way(path, !o->call_depth)) {
1495 renamed = unique_path(o, path, a_sha ? o->branch1 : o->branch2);
1496 }
1497 clean_merge = 0;
1498 handle_delete_modify(o, path, renamed ? renamed : path,
1499 a_sha, a_mode, b_sha, b_mode);
1500 free(renamed);
1501 } else if (!o_sha && !!a_sha != !!b_sha) {
1502 /* directory -> (directory, file) or <nothing> -> (directory, file) */
1503 const char *add_branch;
1504 const char *other_branch;
1505 unsigned mode;
1506 const unsigned char *sha;
1507 const char *conf;
1509 if (a_sha) {
1510 add_branch = o->branch1;
1511 other_branch = o->branch2;
1512 mode = a_mode;
1513 sha = a_sha;
1514 conf = "file/directory";
1515 } else {
1516 add_branch = o->branch2;
1517 other_branch = o->branch1;
1518 mode = b_mode;
1519 sha = b_sha;
1520 conf = "directory/file";
1521 }
1522 if (dir_in_way(path, !o->call_depth)) {
1523 char *new_path = unique_path(o, path, add_branch);
1524 clean_merge = 0;
1525 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1526 "Adding %s as %s",
1527 conf, path, other_branch, path, new_path);
1528 update_file(o, 0, sha, mode, new_path);
1529 if (o->call_depth)
1530 remove_file_from_cache(path);
1531 free(new_path);
1532 } else {
1533 output(o, 2, "Adding %s", path);
1534 update_file(o, 1, sha, mode, path);
1535 }
1536 } else {
1537 entry->processed = 0;
1538 return 1; /* not handled; assume clean until processed */
1539 }
1541 return clean_merge;
1542 }
1544 int merge_trees(struct merge_options *o,
1545 struct tree *head,
1546 struct tree *merge,
1547 struct tree *common,
1548 struct tree **result)
1549 {
1550 int code, clean;
1552 if (o->subtree_shift) {
1553 merge = shift_tree_object(head, merge, o->subtree_shift);
1554 common = shift_tree_object(head, common, o->subtree_shift);
1555 }
1557 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1558 output(o, 0, "Already up-to-date!");
1559 *result = head;
1560 return 1;
1561 }
1563 code = git_merge_trees(o->call_depth, common, head, merge);
1565 if (code != 0) {
1566 if (show(o, 4) || o->call_depth)
1567 die("merging of trees %s and %s failed",
1568 sha1_to_hex(head->object.sha1),
1569 sha1_to_hex(merge->object.sha1));
1570 else
1571 exit(128);
1572 }
1574 if (unmerged_cache()) {
1575 struct string_list *entries, *re_head, *re_merge;
1576 int i;
1577 string_list_clear(&o->current_file_set, 1);
1578 string_list_clear(&o->current_directory_set, 1);
1579 get_files_dirs(o, head);
1580 get_files_dirs(o, merge);
1582 entries = get_unmerged();
1583 record_df_conflict_files(o, entries);
1584 re_head = get_renames(o, head, common, head, merge, entries);
1585 re_merge = get_renames(o, merge, common, head, merge, entries);
1586 clean = process_renames(o, re_head, re_merge);
1587 for (i = 0; i < entries->nr; i++) {
1588 const char *path = entries->items[i].string;
1589 struct stage_data *e = entries->items[i].util;
1590 if (!e->processed
1591 && !process_entry(o, path, e))
1592 clean = 0;
1593 }
1594 for (i = 0; i < entries->nr; i++) {
1595 const char *path = entries->items[i].string;
1596 struct stage_data *e = entries->items[i].util;
1597 if (!e->processed
1598 && !process_df_entry(o, path, e))
1599 clean = 0;
1600 }
1601 for (i = 0; i < entries->nr; i++) {
1602 struct stage_data *e = entries->items[i].util;
1603 if (!e->processed)
1604 die("Unprocessed path??? %s",
1605 entries->items[i].string);
1606 }
1608 string_list_clear(re_merge, 0);
1609 string_list_clear(re_head, 0);
1610 string_list_clear(entries, 1);
1612 }
1613 else
1614 clean = 1;
1616 if (o->call_depth)
1617 *result = write_tree_from_memory(o);
1619 return clean;
1620 }
1622 static struct commit_list *reverse_commit_list(struct commit_list *list)
1623 {
1624 struct commit_list *next = NULL, *current, *backup;
1625 for (current = list; current; current = backup) {
1626 backup = current->next;
1627 current->next = next;
1628 next = current;
1629 }
1630 return next;
1631 }
1633 /*
1634 * Merge the commits h1 and h2, return the resulting virtual
1635 * commit object and a flag indicating the cleanness of the merge.
1636 */
1637 int merge_recursive(struct merge_options *o,
1638 struct commit *h1,
1639 struct commit *h2,
1640 struct commit_list *ca,
1641 struct commit **result)
1642 {
1643 struct commit_list *iter;
1644 struct commit *merged_common_ancestors;
1645 struct tree *mrtree = mrtree;
1646 int clean;
1648 if (show(o, 4)) {
1649 output(o, 4, "Merging:");
1650 output_commit_title(o, h1);
1651 output_commit_title(o, h2);
1652 }
1654 if (!ca) {
1655 ca = get_merge_bases(h1, h2, 1);
1656 ca = reverse_commit_list(ca);
1657 }
1659 if (show(o, 5)) {
1660 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1661 for (iter = ca; iter; iter = iter->next)
1662 output_commit_title(o, iter->item);
1663 }
1665 merged_common_ancestors = pop_commit(&ca);
1666 if (merged_common_ancestors == NULL) {
1667 /* if there is no common ancestor, make an empty tree */
1668 struct tree *tree = xcalloc(1, sizeof(struct tree));
1670 tree->object.parsed = 1;
1671 tree->object.type = OBJ_TREE;
1672 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1673 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1674 }
1676 for (iter = ca; iter; iter = iter->next) {
1677 const char *saved_b1, *saved_b2;
1678 o->call_depth++;
1679 /*
1680 * When the merge fails, the result contains files
1681 * with conflict markers. The cleanness flag is
1682 * ignored, it was never actually used, as result of
1683 * merge_trees has always overwritten it: the committed
1684 * "conflicts" were already resolved.
1685 */
1686 discard_cache();
1687 saved_b1 = o->branch1;
1688 saved_b2 = o->branch2;
1689 o->branch1 = "Temporary merge branch 1";
1690 o->branch2 = "Temporary merge branch 2";
1691 merge_recursive(o, merged_common_ancestors, iter->item,
1692 NULL, &merged_common_ancestors);
1693 o->branch1 = saved_b1;
1694 o->branch2 = saved_b2;
1695 o->call_depth--;
1697 if (!merged_common_ancestors)
1698 die("merge returned no commit");
1699 }
1701 discard_cache();
1702 if (!o->call_depth)
1703 read_cache();
1705 o->ancestor = "merged common ancestors";
1706 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1707 &mrtree);
1709 if (o->call_depth) {
1710 *result = make_virtual_commit(mrtree, "merged tree");
1711 commit_list_insert(h1, &(*result)->parents);
1712 commit_list_insert(h2, &(*result)->parents->next);
1713 }
1714 flush_output(o);
1715 if (show(o, 2))
1716 diff_warn_rename_limit("merge.renamelimit",
1717 o->needed_rename_limit, 0);
1718 return clean;
1719 }
1721 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1722 {
1723 struct object *object;
1725 object = deref_tag(parse_object(sha1), name, strlen(name));
1726 if (!object)
1727 return NULL;
1728 if (object->type == OBJ_TREE)
1729 return make_virtual_commit((struct tree*)object, name);
1730 if (object->type != OBJ_COMMIT)
1731 return NULL;
1732 if (parse_commit((struct commit *)object))
1733 return NULL;
1734 return (struct commit *)object;
1735 }
1737 int merge_recursive_generic(struct merge_options *o,
1738 const unsigned char *head,
1739 const unsigned char *merge,
1740 int num_base_list,
1741 const unsigned char **base_list,
1742 struct commit **result)
1743 {
1744 int clean, index_fd;
1745 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1746 struct commit *head_commit = get_ref(head, o->branch1);
1747 struct commit *next_commit = get_ref(merge, o->branch2);
1748 struct commit_list *ca = NULL;
1750 if (base_list) {
1751 int i;
1752 for (i = 0; i < num_base_list; ++i) {
1753 struct commit *base;
1754 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1755 return error("Could not parse object '%s'",
1756 sha1_to_hex(base_list[i]));
1757 commit_list_insert(base, &ca);
1758 }
1759 }
1761 index_fd = hold_locked_index(lock, 1);
1762 clean = merge_recursive(o, head_commit, next_commit, ca,
1763 result);
1764 if (active_cache_changed &&
1765 (write_cache(index_fd, active_cache, active_nr) ||
1766 commit_locked_index(lock)))
1767 return error("Unable to write index.");
1769 return clean ? 0 : 1;
1770 }
1772 static int merge_recursive_config(const char *var, const char *value, void *cb)
1773 {
1774 struct merge_options *o = cb;
1775 if (!strcmp(var, "merge.verbosity")) {
1776 o->verbosity = git_config_int(var, value);
1777 return 0;
1778 }
1779 if (!strcmp(var, "diff.renamelimit")) {
1780 o->diff_rename_limit = git_config_int(var, value);
1781 return 0;
1782 }
1783 if (!strcmp(var, "merge.renamelimit")) {
1784 o->merge_rename_limit = git_config_int(var, value);
1785 return 0;
1786 }
1787 return git_xmerge_config(var, value, cb);
1788 }
1790 void init_merge_options(struct merge_options *o)
1791 {
1792 memset(o, 0, sizeof(struct merge_options));
1793 o->verbosity = 2;
1794 o->buffer_output = 1;
1795 o->diff_rename_limit = -1;
1796 o->merge_rename_limit = -1;
1797 o->renormalize = 0;
1798 git_config(merge_recursive_config, o);
1799 if (getenv("GIT_MERGE_VERBOSITY"))
1800 o->verbosity =
1801 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1802 if (o->verbosity >= 5)
1803 o->buffer_output = 0;
1804 strbuf_init(&o->obuf, 0);
1805 memset(&o->current_file_set, 0, sizeof(struct string_list));
1806 o->current_file_set.strdup_strings = 1;
1807 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1808 o->current_directory_set.strdup_strings = 1;
1809 memset(&o->df_conflict_file_set, 0, sizeof(struct string_list));
1810 o->df_conflict_file_set.strdup_strings = 1;
1811 }
1813 int parse_merge_opt(struct merge_options *o, const char *s)
1814 {
1815 if (!s || !*s)
1816 return -1;
1817 if (!strcmp(s, "ours"))
1818 o->recursive_variant = MERGE_RECURSIVE_OURS;
1819 else if (!strcmp(s, "theirs"))
1820 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
1821 else if (!strcmp(s, "subtree"))
1822 o->subtree_shift = "";
1823 else if (!prefixcmp(s, "subtree="))
1824 o->subtree_shift = s + strlen("subtree=");
1825 else if (!strcmp(s, "patience"))
1826 o->xdl_opts |= XDF_PATIENCE_DIFF;
1827 else if (!strcmp(s, "ignore-space-change"))
1828 o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1829 else if (!strcmp(s, "ignore-all-space"))
1830 o->xdl_opts |= XDF_IGNORE_WHITESPACE;
1831 else if (!strcmp(s, "ignore-space-at-eol"))
1832 o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
1833 else if (!strcmp(s, "renormalize"))
1834 o->renormalize = 1;
1835 else if (!strcmp(s, "no-renormalize"))
1836 o->renormalize = 0;
1837 else if (!prefixcmp(s, "rename-threshold=")) {
1838 const char *score = s + strlen("rename-threshold=");
1839 if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
1840 return -1;
1841 }
1842 else
1843 return -1;
1844 return 0;
1845 }