A new merge stragety 'subtree'.
[git/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 "cache.h"
7 #include "cache-tree.h"
8 #include "commit.h"
9 #include "blob.h"
10 #include "tree-walk.h"
11 #include "diff.h"
12 #include "diffcore.h"
13 #include "run-command.h"
14 #include "tag.h"
15 #include "unpack-trees.h"
16 #include "path-list.h"
17 #include "xdiff-interface.h"
18
19 static int subtree_merge;
20
21 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
22 {
23 unsigned char shifted[20];
24
25 /*
26 * NEEDSWORK: this limits the recursion depth to hardcoded
27 * value '2' to avoid excessive overhead.
28 */
29 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
30 if (!hashcmp(two->object.sha1, shifted))
31 return two;
32 return lookup_tree(shifted);
33 }
34
35 /*
36 * A virtual commit has
37 * - (const char *)commit->util set to the name, and
38 * - *(int *)commit->object.sha1 set to the virtual id.
39 */
40
41 static unsigned commit_list_count(const struct commit_list *l)
42 {
43 unsigned c = 0;
44 for (; l; l = l->next )
45 c++;
46 return c;
47 }
48
49 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
50 {
51 struct commit *commit = xcalloc(1, sizeof(struct commit));
52 static unsigned virtual_id = 1;
53 commit->tree = tree;
54 commit->util = (void*)comment;
55 *(int*)commit->object.sha1 = virtual_id++;
56 /* avoid warnings */
57 commit->object.parsed = 1;
58 return commit;
59 }
60
61 /*
62 * Since we use get_tree_entry(), which does not put the read object into
63 * the object pool, we cannot rely on a == b.
64 */
65 static int sha_eq(const unsigned char *a, const unsigned char *b)
66 {
67 if (!a && !b)
68 return 2;
69 return a && b && hashcmp(a, b) == 0;
70 }
71
72 /*
73 * Since we want to write the index eventually, we cannot reuse the index
74 * for these (temporary) data.
75 */
76 struct stage_data
77 {
78 struct
79 {
80 unsigned mode;
81 unsigned char sha[20];
82 } stages[4];
83 unsigned processed:1;
84 };
85
86 struct output_buffer
87 {
88 struct output_buffer *next;
89 char *str;
90 };
91
92 static struct path_list current_file_set = {NULL, 0, 0, 1};
93 static struct path_list current_directory_set = {NULL, 0, 0, 1};
94
95 static int call_depth = 0;
96 static int verbosity = 2;
97 static int buffer_output = 1;
98 static int do_progress = 1;
99 static unsigned last_percent;
100 static unsigned merged_cnt;
101 static unsigned total_cnt;
102 static volatile sig_atomic_t progress_update;
103 static struct output_buffer *output_list, *output_end;
104
105 static int show (int v)
106 {
107 return (!call_depth && verbosity >= v) || verbosity >= 5;
108 }
109
110 static void output(int v, const char *fmt, ...)
111 {
112 va_list args;
113 va_start(args, fmt);
114 if (buffer_output && show(v)) {
115 struct output_buffer *b = xmalloc(sizeof(*b));
116 nfvasprintf(&b->str, fmt, args);
117 b->next = NULL;
118 if (output_end)
119 output_end->next = b;
120 else
121 output_list = b;
122 output_end = b;
123 } else if (show(v)) {
124 int i;
125 for (i = call_depth; i--;)
126 fputs(" ", stdout);
127 vfprintf(stdout, fmt, args);
128 fputc('\n', stdout);
129 }
130 va_end(args);
131 }
132
133 static void flush_output()
134 {
135 struct output_buffer *b, *n;
136 for (b = output_list; b; b = n) {
137 int i;
138 for (i = call_depth; i--;)
139 fputs(" ", stdout);
140 fputs(b->str, stdout);
141 fputc('\n', stdout);
142 n = b->next;
143 free(b->str);
144 free(b);
145 }
146 output_list = NULL;
147 output_end = NULL;
148 }
149
150 static void output_commit_title(struct commit *commit)
151 {
152 int i;
153 flush_output();
154 for (i = call_depth; i--;)
155 fputs(" ", stdout);
156 if (commit->util)
157 printf("virtual %s\n", (char *)commit->util);
158 else {
159 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
160 if (parse_commit(commit) != 0)
161 printf("(bad commit)\n");
162 else {
163 const char *s;
164 int len;
165 for (s = commit->buffer; *s; s++)
166 if (*s == '\n' && s[1] == '\n') {
167 s += 2;
168 break;
169 }
170 for (len = 0; s[len] && '\n' != s[len]; len++)
171 ; /* do nothing */
172 printf("%.*s\n", len, s);
173 }
174 }
175 }
176
177 static void progress_interval(int signum)
178 {
179 progress_update = 1;
180 }
181
182 static void setup_progress_signal(void)
183 {
184 struct sigaction sa;
185 struct itimerval v;
186
187 memset(&sa, 0, sizeof(sa));
188 sa.sa_handler = progress_interval;
189 sigemptyset(&sa.sa_mask);
190 sa.sa_flags = SA_RESTART;
191 sigaction(SIGALRM, &sa, NULL);
192
193 v.it_interval.tv_sec = 1;
194 v.it_interval.tv_usec = 0;
195 v.it_value = v.it_interval;
196 setitimer(ITIMER_REAL, &v, NULL);
197 }
198
199 static void display_progress()
200 {
201 unsigned percent = total_cnt ? merged_cnt * 100 / total_cnt : 0;
202 if (progress_update || percent != last_percent) {
203 fprintf(stderr, "%4u%% (%u/%u) done\r",
204 percent, merged_cnt, total_cnt);
205 progress_update = 0;
206 last_percent = percent;
207 }
208 }
209
210 static struct cache_entry *make_cache_entry(unsigned int mode,
211 const unsigned char *sha1, const char *path, int stage, int refresh)
212 {
213 int size, len;
214 struct cache_entry *ce;
215
216 if (!verify_path(path))
217 return NULL;
218
219 len = strlen(path);
220 size = cache_entry_size(len);
221 ce = xcalloc(1, size);
222
223 hashcpy(ce->sha1, sha1);
224 memcpy(ce->name, path, len);
225 ce->ce_flags = create_ce_flags(len, stage);
226 ce->ce_mode = create_ce_mode(mode);
227
228 if (refresh)
229 return refresh_cache_entry(ce, 0);
230
231 return ce;
232 }
233
234 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
235 const char *path, int stage, int refresh, int options)
236 {
237 struct cache_entry *ce;
238 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
239 if (!ce)
240 return error("addinfo_cache failed for path '%s'", path);
241 return add_cache_entry(ce, options);
242 }
243
244 /*
245 * This is a global variable which is used in a number of places but
246 * only written to in the 'merge' function.
247 *
248 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
249 * don't update the working directory.
250 * 0 => Leave unmerged entries in the cache and update
251 * the working directory.
252 */
253 static int index_only = 0;
254
255 static int git_merge_trees(int index_only,
256 struct tree *common,
257 struct tree *head,
258 struct tree *merge)
259 {
260 int rc;
261 struct object_list *trees = NULL;
262 struct unpack_trees_options opts;
263
264 memset(&opts, 0, sizeof(opts));
265 if (index_only)
266 opts.index_only = 1;
267 else
268 opts.update = 1;
269 opts.merge = 1;
270 opts.head_idx = 2;
271 opts.fn = threeway_merge;
272
273 object_list_append(&common->object, &trees);
274 object_list_append(&head->object, &trees);
275 object_list_append(&merge->object, &trees);
276
277 rc = unpack_trees(trees, &opts);
278 cache_tree_free(&active_cache_tree);
279 return rc;
280 }
281
282 static int unmerged_index(void)
283 {
284 int i;
285 for (i = 0; i < active_nr; i++) {
286 struct cache_entry *ce = active_cache[i];
287 if (ce_stage(ce))
288 return 1;
289 }
290 return 0;
291 }
292
293 static struct tree *git_write_tree(void)
294 {
295 struct tree *result = NULL;
296
297 if (unmerged_index()) {
298 int i;
299 output(0, "There are unmerged index entries:");
300 for (i = 0; i < active_nr; i++) {
301 struct cache_entry *ce = active_cache[i];
302 if (ce_stage(ce))
303 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
304 }
305 return NULL;
306 }
307
308 if (!active_cache_tree)
309 active_cache_tree = cache_tree();
310
311 if (!cache_tree_fully_valid(active_cache_tree) &&
312 cache_tree_update(active_cache_tree,
313 active_cache, active_nr, 0, 0) < 0)
314 die("error building trees");
315
316 result = lookup_tree(active_cache_tree->sha1);
317
318 return result;
319 }
320
321 static int save_files_dirs(const unsigned char *sha1,
322 const char *base, int baselen, const char *path,
323 unsigned int mode, int stage)
324 {
325 int len = strlen(path);
326 char *newpath = xmalloc(baselen + len + 1);
327 memcpy(newpath, base, baselen);
328 memcpy(newpath + baselen, path, len);
329 newpath[baselen + len] = '\0';
330
331 if (S_ISDIR(mode))
332 path_list_insert(newpath, &current_directory_set);
333 else
334 path_list_insert(newpath, &current_file_set);
335 free(newpath);
336
337 return READ_TREE_RECURSIVE;
338 }
339
340 static int get_files_dirs(struct tree *tree)
341 {
342 int n;
343 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
344 return 0;
345 n = current_file_set.nr + current_directory_set.nr;
346 return n;
347 }
348
349 /*
350 * Returns a index_entry instance which doesn't have to correspond to
351 * a real cache entry in Git's index.
352 */
353 static struct stage_data *insert_stage_data(const char *path,
354 struct tree *o, struct tree *a, struct tree *b,
355 struct path_list *entries)
356 {
357 struct path_list_item *item;
358 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
359 get_tree_entry(o->object.sha1, path,
360 e->stages[1].sha, &e->stages[1].mode);
361 get_tree_entry(a->object.sha1, path,
362 e->stages[2].sha, &e->stages[2].mode);
363 get_tree_entry(b->object.sha1, path,
364 e->stages[3].sha, &e->stages[3].mode);
365 item = path_list_insert(path, entries);
366 item->util = e;
367 return e;
368 }
369
370 /*
371 * Create a dictionary mapping file names to stage_data objects. The
372 * dictionary contains one entry for every path with a non-zero stage entry.
373 */
374 static struct path_list *get_unmerged(void)
375 {
376 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
377 int i;
378
379 unmerged->strdup_paths = 1;
380 total_cnt += active_nr;
381
382 for (i = 0; i < active_nr; i++, merged_cnt++) {
383 struct path_list_item *item;
384 struct stage_data *e;
385 struct cache_entry *ce = active_cache[i];
386 if (do_progress)
387 display_progress();
388 if (!ce_stage(ce))
389 continue;
390
391 item = path_list_lookup(ce->name, unmerged);
392 if (!item) {
393 item = path_list_insert(ce->name, unmerged);
394 item->util = xcalloc(1, sizeof(struct stage_data));
395 }
396 e = item->util;
397 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
398 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
399 }
400
401 return unmerged;
402 }
403
404 struct rename
405 {
406 struct diff_filepair *pair;
407 struct stage_data *src_entry;
408 struct stage_data *dst_entry;
409 unsigned processed:1;
410 };
411
412 /*
413 * Get information of all renames which occurred between 'o_tree' and
414 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
415 * 'b_tree') to be able to associate the correct cache entries with
416 * the rename information. 'tree' is always equal to either a_tree or b_tree.
417 */
418 static struct path_list *get_renames(struct tree *tree,
419 struct tree *o_tree,
420 struct tree *a_tree,
421 struct tree *b_tree,
422 struct path_list *entries)
423 {
424 int i;
425 struct path_list *renames;
426 struct diff_options opts;
427
428 renames = xcalloc(1, sizeof(struct path_list));
429 diff_setup(&opts);
430 opts.recursive = 1;
431 opts.detect_rename = DIFF_DETECT_RENAME;
432 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
433 if (diff_setup_done(&opts) < 0)
434 die("diff setup failed");
435 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
436 diffcore_std(&opts);
437 for (i = 0; i < diff_queued_diff.nr; ++i) {
438 struct path_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 = path_list_lookup(re->pair->one->path, entries);
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;
454
455 item = path_list_lookup(re->pair->two->path, entries);
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 = path_list_insert(pair->one->path, renames);
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;
468 }
469
470 static int update_stages(const char *path, struct diff_filespec *o,
471 struct diff_filespec *a, struct diff_filespec *b,
472 int clear)
473 {
474 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
475 if (clear)
476 if (remove_file_from_cache(path))
477 return -1;
478 if (o)
479 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
480 return -1;
481 if (a)
482 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
483 return -1;
484 if (b)
485 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
486 return -1;
487 return 0;
488 }
489
490 static int remove_path(const char *name)
491 {
492 int ret, len;
493 char *slash, *dirs;
494
495 ret = unlink(name);
496 if (ret)
497 return ret;
498 len = strlen(name);
499 dirs = xmalloc(len+1);
500 memcpy(dirs, name, len);
501 dirs[len] = '\0';
502 while ((slash = strrchr(name, '/'))) {
503 *slash = '\0';
504 len = slash - name;
505 if (rmdir(name) != 0)
506 break;
507 }
508 free(dirs);
509 return ret;
510 }
511
512 static int remove_file(int clean, const char *path, int no_wd)
513 {
514 int update_cache = index_only || clean;
515 int update_working_directory = !index_only && !no_wd;
516
517 if (update_cache) {
518 if (remove_file_from_cache(path))
519 return -1;
520 }
521 if (update_working_directory) {
522 unlink(path);
523 if (errno != ENOENT || errno != EISDIR)
524 return -1;
525 remove_path(path);
526 }
527 return 0;
528 }
529
530 static char *unique_path(const char *path, const char *branch)
531 {
532 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
533 int suffix = 0;
534 struct stat st;
535 char *p = newpath + strlen(path);
536 strcpy(newpath, path);
537 *(p++) = '~';
538 strcpy(p, branch);
539 for (; *p; ++p)
540 if ('/' == *p)
541 *p = '_';
542 while (path_list_has_path(&current_file_set, newpath) ||
543 path_list_has_path(&current_directory_set, newpath) ||
544 lstat(newpath, &st) == 0)
545 sprintf(p, "_%d", suffix++);
546
547 path_list_insert(newpath, &current_file_set);
548 return newpath;
549 }
550
551 static int mkdir_p(const char *path, unsigned long mode)
552 {
553 /* path points to cache entries, so xstrdup before messing with it */
554 char *buf = xstrdup(path);
555 int result = safe_create_leading_directories(buf);
556 free(buf);
557 return result;
558 }
559
560 static void flush_buffer(int fd, const char *buf, unsigned long size)
561 {
562 while (size > 0) {
563 long ret = write_in_full(fd, buf, size);
564 if (ret < 0) {
565 /* Ignore epipe */
566 if (errno == EPIPE)
567 break;
568 die("merge-recursive: %s", strerror(errno));
569 } else if (!ret) {
570 die("merge-recursive: disk full?");
571 }
572 size -= ret;
573 buf += ret;
574 }
575 }
576
577 static void update_file_flags(const unsigned char *sha,
578 unsigned mode,
579 const char *path,
580 int update_cache,
581 int update_wd)
582 {
583 if (index_only)
584 update_wd = 0;
585
586 if (update_wd) {
587 enum object_type type;
588 void *buf;
589 unsigned long size;
590
591 buf = read_sha1_file(sha, &type, &size);
592 if (!buf)
593 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
594 if (type != OBJ_BLOB)
595 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
596
597 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
598 int fd;
599 if (mkdir_p(path, 0777))
600 die("failed to create path %s: %s", path, strerror(errno));
601 unlink(path);
602 if (mode & 0100)
603 mode = 0777;
604 else
605 mode = 0666;
606 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
607 if (fd < 0)
608 die("failed to open %s: %s", path, strerror(errno));
609 flush_buffer(fd, buf, size);
610 close(fd);
611 } else if (S_ISLNK(mode)) {
612 char *lnk = xmalloc(size + 1);
613 memcpy(lnk, buf, size);
614 lnk[size] = '\0';
615 mkdir_p(path, 0777);
616 unlink(path);
617 symlink(lnk, path);
618 free(lnk);
619 } else
620 die("do not know what to do with %06o %s '%s'",
621 mode, sha1_to_hex(sha), path);
622 }
623 if (update_cache)
624 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
625 }
626
627 static void update_file(int clean,
628 const unsigned char *sha,
629 unsigned mode,
630 const char *path)
631 {
632 update_file_flags(sha, mode, path, index_only || clean, !index_only);
633 }
634
635 /* Low level file merging, update and removal */
636
637 struct merge_file_info
638 {
639 unsigned char sha[20];
640 unsigned mode;
641 unsigned clean:1,
642 merge:1;
643 };
644
645 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
646 {
647 unsigned long size;
648 enum object_type type;
649
650 if (!hashcmp(sha1, null_sha1)) {
651 mm->ptr = xstrdup("");
652 mm->size = 0;
653 return;
654 }
655
656 mm->ptr = read_sha1_file(sha1, &type, &size);
657 if (!mm->ptr || type != OBJ_BLOB)
658 die("unable to read blob object %s", sha1_to_hex(sha1));
659 mm->size = size;
660 }
661
662 static struct merge_file_info merge_file(struct diff_filespec *o,
663 struct diff_filespec *a, struct diff_filespec *b,
664 const char *branch1, const char *branch2)
665 {
666 struct merge_file_info result;
667 result.merge = 0;
668 result.clean = 1;
669
670 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
671 result.clean = 0;
672 if (S_ISREG(a->mode)) {
673 result.mode = a->mode;
674 hashcpy(result.sha, a->sha1);
675 } else {
676 result.mode = b->mode;
677 hashcpy(result.sha, b->sha1);
678 }
679 } else {
680 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
681 result.merge = 1;
682
683 result.mode = a->mode == o->mode ? b->mode: a->mode;
684
685 if (sha_eq(a->sha1, o->sha1))
686 hashcpy(result.sha, b->sha1);
687 else if (sha_eq(b->sha1, o->sha1))
688 hashcpy(result.sha, a->sha1);
689 else if (S_ISREG(a->mode)) {
690 mmfile_t orig, src1, src2;
691 mmbuffer_t result_buf;
692 xpparam_t xpp;
693 char *name1, *name2;
694 int merge_status;
695
696 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
697 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
698
699 fill_mm(o->sha1, &orig);
700 fill_mm(a->sha1, &src1);
701 fill_mm(b->sha1, &src2);
702
703 memset(&xpp, 0, sizeof(xpp));
704 merge_status = xdl_merge(&orig,
705 &src1, name1,
706 &src2, name2,
707 &xpp, XDL_MERGE_ZEALOUS,
708 &result_buf);
709 free(name1);
710 free(name2);
711 free(orig.ptr);
712 free(src1.ptr);
713 free(src2.ptr);
714
715 if ((merge_status < 0) || !result_buf.ptr)
716 die("Failed to execute internal merge");
717
718 if (write_sha1_file(result_buf.ptr, result_buf.size,
719 blob_type, result.sha))
720 die("Unable to add %s to database",
721 a->path);
722
723 free(result_buf.ptr);
724 result.clean = (merge_status == 0);
725 } else {
726 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
727 die("cannot merge modes?");
728
729 hashcpy(result.sha, a->sha1);
730
731 if (!sha_eq(a->sha1, b->sha1))
732 result.clean = 0;
733 }
734 }
735
736 return result;
737 }
738
739 static void conflict_rename_rename(struct rename *ren1,
740 const char *branch1,
741 struct rename *ren2,
742 const char *branch2)
743 {
744 char *del[2];
745 int delp = 0;
746 const char *ren1_dst = ren1->pair->two->path;
747 const char *ren2_dst = ren2->pair->two->path;
748 const char *dst_name1 = ren1_dst;
749 const char *dst_name2 = ren2_dst;
750 if (path_list_has_path(&current_directory_set, ren1_dst)) {
751 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
752 output(1, "%s is a directory in %s added as %s instead",
753 ren1_dst, branch2, dst_name1);
754 remove_file(0, ren1_dst, 0);
755 }
756 if (path_list_has_path(&current_directory_set, ren2_dst)) {
757 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
758 output(1, "%s is a directory in %s added as %s instead",
759 ren2_dst, branch1, dst_name2);
760 remove_file(0, ren2_dst, 0);
761 }
762 if (index_only) {
763 remove_file_from_cache(dst_name1);
764 remove_file_from_cache(dst_name2);
765 /*
766 * Uncomment to leave the conflicting names in the resulting tree
767 *
768 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
769 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
770 */
771 } else {
772 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
773 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
774 }
775 while (delp--)
776 free(del[delp]);
777 }
778
779 static void conflict_rename_dir(struct rename *ren1,
780 const char *branch1)
781 {
782 char *new_path = unique_path(ren1->pair->two->path, branch1);
783 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
784 remove_file(0, ren1->pair->two->path, 0);
785 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
786 free(new_path);
787 }
788
789 static void conflict_rename_rename_2(struct rename *ren1,
790 const char *branch1,
791 struct rename *ren2,
792 const char *branch2)
793 {
794 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
795 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
796 output(1, "Renamed %s to %s and %s to %s instead",
797 ren1->pair->one->path, new_path1,
798 ren2->pair->one->path, new_path2);
799 remove_file(0, ren1->pair->two->path, 0);
800 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
801 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
802 free(new_path2);
803 free(new_path1);
804 }
805
806 static int process_renames(struct path_list *a_renames,
807 struct path_list *b_renames,
808 const char *a_branch,
809 const char *b_branch)
810 {
811 int clean_merge = 1, i, j;
812 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
813 const struct rename *sre;
814
815 for (i = 0; i < a_renames->nr; i++) {
816 sre = a_renames->items[i].util;
817 path_list_insert(sre->pair->two->path, &a_by_dst)->util
818 = sre->dst_entry;
819 }
820 for (i = 0; i < b_renames->nr; i++) {
821 sre = b_renames->items[i].util;
822 path_list_insert(sre->pair->two->path, &b_by_dst)->util
823 = sre->dst_entry;
824 }
825
826 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
827 int compare;
828 char *src;
829 struct path_list *renames1, *renames2, *renames2Dst;
830 struct rename *ren1 = NULL, *ren2 = NULL;
831 const char *branch1, *branch2;
832 const char *ren1_src, *ren1_dst;
833
834 if (i >= a_renames->nr) {
835 compare = 1;
836 ren2 = b_renames->items[j++].util;
837 } else if (j >= b_renames->nr) {
838 compare = -1;
839 ren1 = a_renames->items[i++].util;
840 } else {
841 compare = strcmp(a_renames->items[i].path,
842 b_renames->items[j].path);
843 if (compare <= 0)
844 ren1 = a_renames->items[i++].util;
845 if (compare >= 0)
846 ren2 = b_renames->items[j++].util;
847 }
848
849 /* TODO: refactor, so that 1/2 are not needed */
850 if (ren1) {
851 renames1 = a_renames;
852 renames2 = b_renames;
853 renames2Dst = &b_by_dst;
854 branch1 = a_branch;
855 branch2 = b_branch;
856 } else {
857 struct rename *tmp;
858 renames1 = b_renames;
859 renames2 = a_renames;
860 renames2Dst = &a_by_dst;
861 branch1 = b_branch;
862 branch2 = a_branch;
863 tmp = ren2;
864 ren2 = ren1;
865 ren1 = tmp;
866 }
867 src = ren1->pair->one->path;
868
869 ren1->dst_entry->processed = 1;
870 ren1->src_entry->processed = 1;
871
872 if (ren1->processed)
873 continue;
874 ren1->processed = 1;
875
876 ren1_src = ren1->pair->one->path;
877 ren1_dst = ren1->pair->two->path;
878
879 if (ren2) {
880 const char *ren2_src = ren2->pair->one->path;
881 const char *ren2_dst = ren2->pair->two->path;
882 /* Renamed in 1 and renamed in 2 */
883 if (strcmp(ren1_src, ren2_src) != 0)
884 die("ren1.src != ren2.src");
885 ren2->dst_entry->processed = 1;
886 ren2->processed = 1;
887 if (strcmp(ren1_dst, ren2_dst) != 0) {
888 clean_merge = 0;
889 output(1, "CONFLICT (rename/rename): "
890 "Rename \"%s\"->\"%s\" in branch \"%s\" "
891 "rename \"%s\"->\"%s\" in \"%s\"%s",
892 src, ren1_dst, branch1,
893 src, ren2_dst, branch2,
894 index_only ? " (left unresolved)": "");
895 if (index_only) {
896 remove_file_from_cache(src);
897 update_file(0, ren1->pair->one->sha1,
898 ren1->pair->one->mode, src);
899 }
900 conflict_rename_rename(ren1, branch1, ren2, branch2);
901 } else {
902 struct merge_file_info mfi;
903 remove_file(1, ren1_src, 1);
904 mfi = merge_file(ren1->pair->one,
905 ren1->pair->two,
906 ren2->pair->two,
907 branch1,
908 branch2);
909 if (mfi.merge || !mfi.clean)
910 output(1, "Renamed %s->%s", src, ren1_dst);
911
912 if (mfi.merge)
913 output(2, "Auto-merged %s", ren1_dst);
914
915 if (!mfi.clean) {
916 output(1, "CONFLICT (content): merge conflict in %s",
917 ren1_dst);
918 clean_merge = 0;
919
920 if (!index_only)
921 update_stages(ren1_dst,
922 ren1->pair->one,
923 ren1->pair->two,
924 ren2->pair->two,
925 1 /* clear */);
926 }
927 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
928 }
929 } else {
930 /* Renamed in 1, maybe changed in 2 */
931 struct path_list_item *item;
932 /* we only use sha1 and mode of these */
933 struct diff_filespec src_other, dst_other;
934 int try_merge, stage = a_renames == renames1 ? 3: 2;
935
936 remove_file(1, ren1_src, index_only || stage == 3);
937
938 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
939 src_other.mode = ren1->src_entry->stages[stage].mode;
940 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
941 dst_other.mode = ren1->dst_entry->stages[stage].mode;
942
943 try_merge = 0;
944
945 if (path_list_has_path(&current_directory_set, ren1_dst)) {
946 clean_merge = 0;
947 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
948 " directory %s added in %s",
949 ren1_src, ren1_dst, branch1,
950 ren1_dst, branch2);
951 conflict_rename_dir(ren1, branch1);
952 } else if (sha_eq(src_other.sha1, null_sha1)) {
953 clean_merge = 0;
954 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
955 "and deleted in %s",
956 ren1_src, ren1_dst, branch1,
957 branch2);
958 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
959 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
960 const char *new_path;
961 clean_merge = 0;
962 try_merge = 1;
963 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
964 "%s added in %s",
965 ren1_src, ren1_dst, branch1,
966 ren1_dst, branch2);
967 new_path = unique_path(ren1_dst, branch2);
968 output(1, "Added as %s instead", new_path);
969 update_file(0, dst_other.sha1, dst_other.mode, new_path);
970 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
971 ren2 = item->util;
972 clean_merge = 0;
973 ren2->processed = 1;
974 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
975 "Renamed %s->%s in %s",
976 ren1_src, ren1_dst, branch1,
977 ren2->pair->one->path, ren2->pair->two->path, branch2);
978 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
979 } else
980 try_merge = 1;
981
982 if (try_merge) {
983 struct diff_filespec *o, *a, *b;
984 struct merge_file_info mfi;
985 src_other.path = (char *)ren1_src;
986
987 o = ren1->pair->one;
988 if (a_renames == renames1) {
989 a = ren1->pair->two;
990 b = &src_other;
991 } else {
992 b = ren1->pair->two;
993 a = &src_other;
994 }
995 mfi = merge_file(o, a, b,
996 a_branch, b_branch);
997
998 if (mfi.merge || !mfi.clean)
999 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
1000 if (mfi.merge)
1001 output(2, "Auto-merged %s", ren1_dst);
1002 if (!mfi.clean) {
1003 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
1004 ren1_dst);
1005 clean_merge = 0;
1006
1007 if (!index_only)
1008 update_stages(ren1_dst,
1009 o, a, b, 1);
1010 }
1011 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1012 }
1013 }
1014 }
1015 path_list_clear(&a_by_dst, 0);
1016 path_list_clear(&b_by_dst, 0);
1017
1018 return clean_merge;
1019 }
1020
1021 static unsigned char *has_sha(const unsigned char *sha)
1022 {
1023 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
1024 }
1025
1026 /* Per entry merge function */
1027 static int process_entry(const char *path, struct stage_data *entry,
1028 const char *branch1,
1029 const char *branch2)
1030 {
1031 /*
1032 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1033 print_index_entry("\tpath: ", entry);
1034 */
1035 int clean_merge = 1;
1036 unsigned char *o_sha = has_sha(entry->stages[1].sha);
1037 unsigned char *a_sha = has_sha(entry->stages[2].sha);
1038 unsigned char *b_sha = has_sha(entry->stages[3].sha);
1039 unsigned o_mode = entry->stages[1].mode;
1040 unsigned a_mode = entry->stages[2].mode;
1041 unsigned b_mode = entry->stages[3].mode;
1042
1043 if (o_sha && (!a_sha || !b_sha)) {
1044 /* Case A: Deleted in one */
1045 if ((!a_sha && !b_sha) ||
1046 (sha_eq(a_sha, o_sha) && !b_sha) ||
1047 (!a_sha && sha_eq(b_sha, o_sha))) {
1048 /* Deleted in both or deleted in one and
1049 * unchanged in the other */
1050 if (a_sha)
1051 output(2, "Removed %s", path);
1052 /* do not touch working file if it did not exist */
1053 remove_file(1, path, !a_sha);
1054 } else {
1055 /* Deleted in one and changed in the other */
1056 clean_merge = 0;
1057 if (!a_sha) {
1058 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1059 "and modified in %s. Version %s of %s left in tree.",
1060 path, branch1,
1061 branch2, branch2, path);
1062 update_file(0, b_sha, b_mode, path);
1063 } else {
1064 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1065 "and modified in %s. Version %s of %s left in tree.",
1066 path, branch2,
1067 branch1, branch1, path);
1068 update_file(0, a_sha, a_mode, path);
1069 }
1070 }
1071
1072 } else if ((!o_sha && a_sha && !b_sha) ||
1073 (!o_sha && !a_sha && b_sha)) {
1074 /* Case B: Added in one. */
1075 const char *add_branch;
1076 const char *other_branch;
1077 unsigned mode;
1078 const unsigned char *sha;
1079 const char *conf;
1080
1081 if (a_sha) {
1082 add_branch = branch1;
1083 other_branch = branch2;
1084 mode = a_mode;
1085 sha = a_sha;
1086 conf = "file/directory";
1087 } else {
1088 add_branch = branch2;
1089 other_branch = branch1;
1090 mode = b_mode;
1091 sha = b_sha;
1092 conf = "directory/file";
1093 }
1094 if (path_list_has_path(&current_directory_set, path)) {
1095 const char *new_path = unique_path(path, add_branch);
1096 clean_merge = 0;
1097 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1098 "Added %s as %s",
1099 conf, path, other_branch, path, new_path);
1100 remove_file(0, path, 0);
1101 update_file(0, sha, mode, new_path);
1102 } else {
1103 output(2, "Added %s", path);
1104 update_file(1, sha, mode, path);
1105 }
1106 } else if (a_sha && b_sha) {
1107 /* Case C: Added in both (check for same permissions) and */
1108 /* case D: Modified in both, but differently. */
1109 const char *reason = "content";
1110 struct merge_file_info mfi;
1111 struct diff_filespec o, a, b;
1112
1113 if (!o_sha) {
1114 reason = "add/add";
1115 o_sha = (unsigned char *)null_sha1;
1116 }
1117 output(2, "Auto-merged %s", path);
1118 o.path = a.path = b.path = (char *)path;
1119 hashcpy(o.sha1, o_sha);
1120 o.mode = o_mode;
1121 hashcpy(a.sha1, a_sha);
1122 a.mode = a_mode;
1123 hashcpy(b.sha1, b_sha);
1124 b.mode = b_mode;
1125
1126 mfi = merge_file(&o, &a, &b,
1127 branch1, branch2);
1128
1129 if (mfi.clean)
1130 update_file(1, mfi.sha, mfi.mode, path);
1131 else {
1132 clean_merge = 0;
1133 output(1, "CONFLICT (%s): Merge conflict in %s",
1134 reason, path);
1135
1136 if (index_only)
1137 update_file(0, mfi.sha, mfi.mode, path);
1138 else
1139 update_file_flags(mfi.sha, mfi.mode, path,
1140 0 /* update_cache */, 1 /* update_working_directory */);
1141 }
1142 } else
1143 die("Fatal merge failure, shouldn't happen.");
1144
1145 return clean_merge;
1146 }
1147
1148 static int merge_trees(struct tree *head,
1149 struct tree *merge,
1150 struct tree *common,
1151 const char *branch1,
1152 const char *branch2,
1153 struct tree **result)
1154 {
1155 int code, clean;
1156
1157 if (subtree_merge) {
1158 merge = shift_tree_object(head, merge);
1159 common = shift_tree_object(head, common);
1160 }
1161
1162 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1163 output(0, "Already uptodate!");
1164 *result = head;
1165 return 1;
1166 }
1167
1168 code = git_merge_trees(index_only, common, head, merge);
1169
1170 if (code != 0)
1171 die("merging of trees %s and %s failed",
1172 sha1_to_hex(head->object.sha1),
1173 sha1_to_hex(merge->object.sha1));
1174
1175 if (unmerged_index()) {
1176 struct path_list *entries, *re_head, *re_merge;
1177 int i;
1178 path_list_clear(&current_file_set, 1);
1179 path_list_clear(&current_directory_set, 1);
1180 get_files_dirs(head);
1181 get_files_dirs(merge);
1182
1183 entries = get_unmerged();
1184 re_head = get_renames(head, common, head, merge, entries);
1185 re_merge = get_renames(merge, common, head, merge, entries);
1186 clean = process_renames(re_head, re_merge,
1187 branch1, branch2);
1188 total_cnt += entries->nr;
1189 for (i = 0; i < entries->nr; i++, merged_cnt++) {
1190 const char *path = entries->items[i].path;
1191 struct stage_data *e = entries->items[i].util;
1192 if (!e->processed
1193 && !process_entry(path, e, branch1, branch2))
1194 clean = 0;
1195 if (do_progress)
1196 display_progress();
1197 }
1198
1199 path_list_clear(re_merge, 0);
1200 path_list_clear(re_head, 0);
1201 path_list_clear(entries, 1);
1202
1203 }
1204 else
1205 clean = 1;
1206
1207 if (index_only)
1208 *result = git_write_tree();
1209
1210 return clean;
1211 }
1212
1213 static struct commit_list *reverse_commit_list(struct commit_list *list)
1214 {
1215 struct commit_list *next = NULL, *current, *backup;
1216 for (current = list; current; current = backup) {
1217 backup = current->next;
1218 current->next = next;
1219 next = current;
1220 }
1221 return next;
1222 }
1223
1224 /*
1225 * Merge the commits h1 and h2, return the resulting virtual
1226 * commit object and a flag indicating the cleanness of the merge.
1227 */
1228 static int merge(struct commit *h1,
1229 struct commit *h2,
1230 const char *branch1,
1231 const char *branch2,
1232 struct commit_list *ca,
1233 struct commit **result)
1234 {
1235 struct commit_list *iter;
1236 struct commit *merged_common_ancestors;
1237 struct tree *mrtree;
1238 int clean;
1239
1240 if (show(4)) {
1241 output(4, "Merging:");
1242 output_commit_title(h1);
1243 output_commit_title(h2);
1244 }
1245
1246 if (!ca) {
1247 ca = get_merge_bases(h1, h2, 1);
1248 ca = reverse_commit_list(ca);
1249 }
1250
1251 if (show(5)) {
1252 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1253 for (iter = ca; iter; iter = iter->next)
1254 output_commit_title(iter->item);
1255 }
1256
1257 merged_common_ancestors = pop_commit(&ca);
1258 if (merged_common_ancestors == NULL) {
1259 /* if there is no common ancestor, make an empty tree */
1260 struct tree *tree = xcalloc(1, sizeof(struct tree));
1261
1262 tree->object.parsed = 1;
1263 tree->object.type = OBJ_TREE;
1264 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1265 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1266 }
1267
1268 for (iter = ca; iter; iter = iter->next) {
1269 call_depth++;
1270 /*
1271 * When the merge fails, the result contains files
1272 * with conflict markers. The cleanness flag is
1273 * ignored, it was never actually used, as result of
1274 * merge_trees has always overwritten it: the committed
1275 * "conflicts" were already resolved.
1276 */
1277 discard_cache();
1278 merge(merged_common_ancestors, iter->item,
1279 "Temporary merge branch 1",
1280 "Temporary merge branch 2",
1281 NULL,
1282 &merged_common_ancestors);
1283 call_depth--;
1284
1285 if (!merged_common_ancestors)
1286 die("merge returned no commit");
1287 }
1288
1289 discard_cache();
1290 if (!call_depth) {
1291 read_cache();
1292 index_only = 0;
1293 } else
1294 index_only = 1;
1295
1296 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1297 branch1, branch2, &mrtree);
1298
1299 if (index_only) {
1300 *result = make_virtual_commit(mrtree, "merged tree");
1301 commit_list_insert(h1, &(*result)->parents);
1302 commit_list_insert(h2, &(*result)->parents->next);
1303 }
1304 if (!call_depth && do_progress) {
1305 /* Make sure we end at 100% */
1306 if (!total_cnt)
1307 total_cnt = 1;
1308 merged_cnt = total_cnt;
1309 progress_update = 1;
1310 display_progress();
1311 fputc('\n', stderr);
1312 }
1313 flush_output();
1314 return clean;
1315 }
1316
1317 static const char *better_branch_name(const char *branch)
1318 {
1319 static char githead_env[8 + 40 + 1];
1320 char *name;
1321
1322 if (strlen(branch) != 40)
1323 return branch;
1324 sprintf(githead_env, "GITHEAD_%s", branch);
1325 name = getenv(githead_env);
1326 return name ? name : branch;
1327 }
1328
1329 static struct commit *get_ref(const char *ref)
1330 {
1331 unsigned char sha1[20];
1332 struct object *object;
1333
1334 if (get_sha1(ref, sha1))
1335 die("Could not resolve ref '%s'", ref);
1336 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1337 if (object->type == OBJ_TREE)
1338 return make_virtual_commit((struct tree*)object,
1339 better_branch_name(ref));
1340 if (object->type != OBJ_COMMIT)
1341 return NULL;
1342 if (parse_commit((struct commit *)object))
1343 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1344 return (struct commit *)object;
1345 }
1346
1347 static int merge_config(const char *var, const char *value)
1348 {
1349 if (!strcasecmp(var, "merge.verbosity")) {
1350 verbosity = git_config_int(var, value);
1351 return 0;
1352 }
1353 return git_default_config(var, value);
1354 }
1355
1356 int main(int argc, char *argv[])
1357 {
1358 static const char *bases[20];
1359 static unsigned bases_count = 0;
1360 int i, clean;
1361 const char *branch1, *branch2;
1362 struct commit *result, *h1, *h2;
1363 struct commit_list *ca = NULL;
1364 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1365 int index_fd;
1366
1367 if (argv[0]) {
1368 int namelen = strlen(argv[0]);
1369 if (8 < namelen &&
1370 !strcmp(argv[0] + namelen - 8, "-subtree"))
1371 subtree_merge = 1;
1372 }
1373
1374 git_config(merge_config);
1375 if (getenv("GIT_MERGE_VERBOSITY"))
1376 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1377
1378 if (argc < 4)
1379 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1380
1381 for (i = 1; i < argc; ++i) {
1382 if (!strcmp(argv[i], "--"))
1383 break;
1384 if (bases_count < sizeof(bases)/sizeof(*bases))
1385 bases[bases_count++] = argv[i];
1386 }
1387 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1388 die("Not handling anything other than two heads merge.");
1389 if (verbosity >= 5) {
1390 buffer_output = 0;
1391 do_progress = 0;
1392 }
1393 else
1394 do_progress = isatty(1);
1395
1396 branch1 = argv[++i];
1397 branch2 = argv[++i];
1398
1399 h1 = get_ref(branch1);
1400 h2 = get_ref(branch2);
1401
1402 branch1 = better_branch_name(branch1);
1403 branch2 = better_branch_name(branch2);
1404
1405 if (do_progress)
1406 setup_progress_signal();
1407 if (show(3))
1408 printf("Merging %s with %s\n", branch1, branch2);
1409
1410 index_fd = hold_locked_index(lock, 1);
1411
1412 for (i = 0; i < bases_count; i++) {
1413 struct commit *ancestor = get_ref(bases[i]);
1414 ca = commit_list_insert(ancestor, &ca);
1415 }
1416 clean = merge(h1, h2, branch1, branch2, ca, &result);
1417
1418 if (active_cache_changed &&
1419 (write_cache(index_fd, active_cache, active_nr) ||
1420 close(index_fd) || commit_locked_index(lock)))
1421 die ("unable to write %s", get_index_file());
1422
1423 return clean ? 0: 1;
1424 }