Allow the user to control the verbosity of merge-recursive.
[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 /*
20 * A virtual commit has
21 * - (const char *)commit->util set to the name, and
22 * - *(int *)commit->object.sha1 set to the virtual id.
23 */
24
25 static unsigned commit_list_count(const struct commit_list *l)
26 {
27 unsigned c = 0;
28 for (; l; l = l->next )
29 c++;
30 return c;
31 }
32
33 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
34 {
35 struct commit *commit = xcalloc(1, sizeof(struct commit));
36 static unsigned virtual_id = 1;
37 commit->tree = tree;
38 commit->util = (void*)comment;
39 *(int*)commit->object.sha1 = virtual_id++;
40 /* avoid warnings */
41 commit->object.parsed = 1;
42 return commit;
43 }
44
45 /*
46 * Since we use get_tree_entry(), which does not put the read object into
47 * the object pool, we cannot rely on a == b.
48 */
49 static int sha_eq(const unsigned char *a, const unsigned char *b)
50 {
51 if (!a && !b)
52 return 2;
53 return a && b && hashcmp(a, b) == 0;
54 }
55
56 /*
57 * Since we want to write the index eventually, we cannot reuse the index
58 * for these (temporary) data.
59 */
60 struct stage_data
61 {
62 struct
63 {
64 unsigned mode;
65 unsigned char sha[20];
66 } stages[4];
67 unsigned processed:1;
68 };
69
70 static struct path_list current_file_set = {NULL, 0, 0, 1};
71 static struct path_list current_directory_set = {NULL, 0, 0, 1};
72
73 static int call_depth = 0;
74 static int verbosity = 2;
75
76 static int show (int v)
77 {
78 return (!call_depth && verbosity >= v) || verbosity >= 5;
79 }
80
81 static void output(int v, const char *fmt, ...)
82 {
83 va_list args;
84 va_start(args, fmt);
85 if (show(v)) {
86 int i;
87 for (i = call_depth; i--;)
88 fputs(" ", stdout);
89 vfprintf(stdout, fmt, args);
90 fputc('\n', stdout);
91 }
92 va_end(args);
93 }
94
95 static void output_commit_title(struct commit *commit)
96 {
97 int i;
98 for (i = call_depth; i--;)
99 fputs(" ", stdout);
100 if (commit->util)
101 printf("virtual %s\n", (char *)commit->util);
102 else {
103 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
104 if (parse_commit(commit) != 0)
105 printf("(bad commit)\n");
106 else {
107 const char *s;
108 int len;
109 for (s = commit->buffer; *s; s++)
110 if (*s == '\n' && s[1] == '\n') {
111 s += 2;
112 break;
113 }
114 for (len = 0; s[len] && '\n' != s[len]; len++)
115 ; /* do nothing */
116 printf("%.*s\n", len, s);
117 }
118 }
119 }
120
121 static struct cache_entry *make_cache_entry(unsigned int mode,
122 const unsigned char *sha1, const char *path, int stage, int refresh)
123 {
124 int size, len;
125 struct cache_entry *ce;
126
127 if (!verify_path(path))
128 return NULL;
129
130 len = strlen(path);
131 size = cache_entry_size(len);
132 ce = xcalloc(1, size);
133
134 hashcpy(ce->sha1, sha1);
135 memcpy(ce->name, path, len);
136 ce->ce_flags = create_ce_flags(len, stage);
137 ce->ce_mode = create_ce_mode(mode);
138
139 if (refresh)
140 return refresh_cache_entry(ce, 0);
141
142 return ce;
143 }
144
145 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
146 const char *path, int stage, int refresh, int options)
147 {
148 struct cache_entry *ce;
149 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
150 if (!ce)
151 return error("cache_addinfo failed: %s", strerror(cache_errno));
152 return add_cache_entry(ce, options);
153 }
154
155 /*
156 * This is a global variable which is used in a number of places but
157 * only written to in the 'merge' function.
158 *
159 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
160 * don't update the working directory.
161 * 0 => Leave unmerged entries in the cache and update
162 * the working directory.
163 */
164 static int index_only = 0;
165
166 static int git_merge_trees(int index_only,
167 struct tree *common,
168 struct tree *head,
169 struct tree *merge)
170 {
171 int rc;
172 struct object_list *trees = NULL;
173 struct unpack_trees_options opts;
174
175 memset(&opts, 0, sizeof(opts));
176 if (index_only)
177 opts.index_only = 1;
178 else
179 opts.update = 1;
180 opts.merge = 1;
181 opts.head_idx = 2;
182 opts.fn = threeway_merge;
183
184 object_list_append(&common->object, &trees);
185 object_list_append(&head->object, &trees);
186 object_list_append(&merge->object, &trees);
187
188 rc = unpack_trees(trees, &opts);
189 cache_tree_free(&active_cache_tree);
190 return rc;
191 }
192
193 static int unmerged_index(void)
194 {
195 int i;
196 for (i = 0; i < active_nr; i++) {
197 struct cache_entry *ce = active_cache[i];
198 if (ce_stage(ce))
199 return 1;
200 }
201 return 0;
202 }
203
204 static struct tree *git_write_tree(void)
205 {
206 struct tree *result = NULL;
207
208 if (unmerged_index())
209 return NULL;
210
211 if (!active_cache_tree)
212 active_cache_tree = cache_tree();
213
214 if (!cache_tree_fully_valid(active_cache_tree) &&
215 cache_tree_update(active_cache_tree,
216 active_cache, active_nr, 0, 0) < 0)
217 die("error building trees");
218
219 result = lookup_tree(active_cache_tree->sha1);
220
221 return result;
222 }
223
224 static int save_files_dirs(const unsigned char *sha1,
225 const char *base, int baselen, const char *path,
226 unsigned int mode, int stage)
227 {
228 int len = strlen(path);
229 char *newpath = xmalloc(baselen + len + 1);
230 memcpy(newpath, base, baselen);
231 memcpy(newpath + baselen, path, len);
232 newpath[baselen + len] = '\0';
233
234 if (S_ISDIR(mode))
235 path_list_insert(newpath, &current_directory_set);
236 else
237 path_list_insert(newpath, &current_file_set);
238 free(newpath);
239
240 return READ_TREE_RECURSIVE;
241 }
242
243 static int get_files_dirs(struct tree *tree)
244 {
245 int n;
246 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
247 return 0;
248 n = current_file_set.nr + current_directory_set.nr;
249 return n;
250 }
251
252 /*
253 * Returns a index_entry instance which doesn't have to correspond to
254 * a real cache entry in Git's index.
255 */
256 static struct stage_data *insert_stage_data(const char *path,
257 struct tree *o, struct tree *a, struct tree *b,
258 struct path_list *entries)
259 {
260 struct path_list_item *item;
261 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
262 get_tree_entry(o->object.sha1, path,
263 e->stages[1].sha, &e->stages[1].mode);
264 get_tree_entry(a->object.sha1, path,
265 e->stages[2].sha, &e->stages[2].mode);
266 get_tree_entry(b->object.sha1, path,
267 e->stages[3].sha, &e->stages[3].mode);
268 item = path_list_insert(path, entries);
269 item->util = e;
270 return e;
271 }
272
273 /*
274 * Create a dictionary mapping file names to stage_data objects. The
275 * dictionary contains one entry for every path with a non-zero stage entry.
276 */
277 static struct path_list *get_unmerged(void)
278 {
279 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
280 int i;
281
282 unmerged->strdup_paths = 1;
283
284 for (i = 0; i < active_nr; i++) {
285 struct path_list_item *item;
286 struct stage_data *e;
287 struct cache_entry *ce = active_cache[i];
288 if (!ce_stage(ce))
289 continue;
290
291 item = path_list_lookup(ce->name, unmerged);
292 if (!item) {
293 item = path_list_insert(ce->name, unmerged);
294 item->util = xcalloc(1, sizeof(struct stage_data));
295 }
296 e = item->util;
297 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
298 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
299 }
300
301 return unmerged;
302 }
303
304 struct rename
305 {
306 struct diff_filepair *pair;
307 struct stage_data *src_entry;
308 struct stage_data *dst_entry;
309 unsigned processed:1;
310 };
311
312 /*
313 * Get information of all renames which occured between 'o_tree' and
314 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
315 * 'b_tree') to be able to associate the correct cache entries with
316 * the rename information. 'tree' is always equal to either a_tree or b_tree.
317 */
318 static struct path_list *get_renames(struct tree *tree,
319 struct tree *o_tree,
320 struct tree *a_tree,
321 struct tree *b_tree,
322 struct path_list *entries)
323 {
324 int i;
325 struct path_list *renames;
326 struct diff_options opts;
327
328 renames = xcalloc(1, sizeof(struct path_list));
329 diff_setup(&opts);
330 opts.recursive = 1;
331 opts.detect_rename = DIFF_DETECT_RENAME;
332 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
333 if (diff_setup_done(&opts) < 0)
334 die("diff setup failed");
335 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
336 diffcore_std(&opts);
337 for (i = 0; i < diff_queued_diff.nr; ++i) {
338 struct path_list_item *item;
339 struct rename *re;
340 struct diff_filepair *pair = diff_queued_diff.queue[i];
341 if (pair->status != 'R') {
342 diff_free_filepair(pair);
343 continue;
344 }
345 re = xmalloc(sizeof(*re));
346 re->processed = 0;
347 re->pair = pair;
348 item = path_list_lookup(re->pair->one->path, entries);
349 if (!item)
350 re->src_entry = insert_stage_data(re->pair->one->path,
351 o_tree, a_tree, b_tree, entries);
352 else
353 re->src_entry = item->util;
354
355 item = path_list_lookup(re->pair->two->path, entries);
356 if (!item)
357 re->dst_entry = insert_stage_data(re->pair->two->path,
358 o_tree, a_tree, b_tree, entries);
359 else
360 re->dst_entry = item->util;
361 item = path_list_insert(pair->one->path, renames);
362 item->util = re;
363 }
364 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
365 diff_queued_diff.nr = 0;
366 diff_flush(&opts);
367 return renames;
368 }
369
370 static int update_stages(const char *path, struct diff_filespec *o,
371 struct diff_filespec *a, struct diff_filespec *b,
372 int clear)
373 {
374 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
375 if (clear)
376 if (remove_file_from_cache(path))
377 return -1;
378 if (o)
379 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
380 return -1;
381 if (a)
382 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
383 return -1;
384 if (b)
385 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
386 return -1;
387 return 0;
388 }
389
390 static int remove_path(const char *name)
391 {
392 int ret, len;
393 char *slash, *dirs;
394
395 ret = unlink(name);
396 if (ret)
397 return ret;
398 len = strlen(name);
399 dirs = xmalloc(len+1);
400 memcpy(dirs, name, len);
401 dirs[len] = '\0';
402 while ((slash = strrchr(name, '/'))) {
403 *slash = '\0';
404 len = slash - name;
405 if (rmdir(name) != 0)
406 break;
407 }
408 free(dirs);
409 return ret;
410 }
411
412 static int remove_file(int clean, const char *path, int no_wd)
413 {
414 int update_cache = index_only || clean;
415 int update_working_directory = !index_only && !no_wd;
416
417 if (update_cache) {
418 if (remove_file_from_cache(path))
419 return -1;
420 }
421 if (update_working_directory) {
422 unlink(path);
423 if (errno != ENOENT || errno != EISDIR)
424 return -1;
425 remove_path(path);
426 }
427 return 0;
428 }
429
430 static char *unique_path(const char *path, const char *branch)
431 {
432 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
433 int suffix = 0;
434 struct stat st;
435 char *p = newpath + strlen(path);
436 strcpy(newpath, path);
437 *(p++) = '~';
438 strcpy(p, branch);
439 for (; *p; ++p)
440 if ('/' == *p)
441 *p = '_';
442 while (path_list_has_path(&current_file_set, newpath) ||
443 path_list_has_path(&current_directory_set, newpath) ||
444 lstat(newpath, &st) == 0)
445 sprintf(p, "_%d", suffix++);
446
447 path_list_insert(newpath, &current_file_set);
448 return newpath;
449 }
450
451 static int mkdir_p(const char *path, unsigned long mode)
452 {
453 /* path points to cache entries, so xstrdup before messing with it */
454 char *buf = xstrdup(path);
455 int result = safe_create_leading_directories(buf);
456 free(buf);
457 return result;
458 }
459
460 static void flush_buffer(int fd, const char *buf, unsigned long size)
461 {
462 while (size > 0) {
463 long ret = write_in_full(fd, buf, size);
464 if (ret < 0) {
465 /* Ignore epipe */
466 if (errno == EPIPE)
467 break;
468 die("merge-recursive: %s", strerror(errno));
469 } else if (!ret) {
470 die("merge-recursive: disk full?");
471 }
472 size -= ret;
473 buf += ret;
474 }
475 }
476
477 static void update_file_flags(const unsigned char *sha,
478 unsigned mode,
479 const char *path,
480 int update_cache,
481 int update_wd)
482 {
483 if (index_only)
484 update_wd = 0;
485
486 if (update_wd) {
487 char type[20];
488 void *buf;
489 unsigned long size;
490
491 buf = read_sha1_file(sha, type, &size);
492 if (!buf)
493 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
494 if (strcmp(type, blob_type) != 0)
495 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
496
497 if (S_ISREG(mode)) {
498 int fd;
499 if (mkdir_p(path, 0777))
500 die("failed to create path %s: %s", path, strerror(errno));
501 unlink(path);
502 if (mode & 0100)
503 mode = 0777;
504 else
505 mode = 0666;
506 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
507 if (fd < 0)
508 die("failed to open %s: %s", path, strerror(errno));
509 flush_buffer(fd, buf, size);
510 close(fd);
511 } else if (S_ISLNK(mode)) {
512 char *lnk = xmalloc(size + 1);
513 memcpy(lnk, buf, size);
514 lnk[size] = '\0';
515 mkdir_p(path, 0777);
516 unlink(lnk);
517 symlink(lnk, path);
518 } else
519 die("do not know what to do with %06o %s '%s'",
520 mode, sha1_to_hex(sha), path);
521 }
522 if (update_cache)
523 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
524 }
525
526 static void update_file(int clean,
527 const unsigned char *sha,
528 unsigned mode,
529 const char *path)
530 {
531 update_file_flags(sha, mode, path, index_only || clean, !index_only);
532 }
533
534 /* Low level file merging, update and removal */
535
536 struct merge_file_info
537 {
538 unsigned char sha[20];
539 unsigned mode;
540 unsigned clean:1,
541 merge:1;
542 };
543
544 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
545 {
546 unsigned long size;
547 char type[20];
548
549 if (!hashcmp(sha1, null_sha1)) {
550 mm->ptr = xstrdup("");
551 mm->size = 0;
552 return;
553 }
554
555 mm->ptr = read_sha1_file(sha1, type, &size);
556 if (!mm->ptr || strcmp(type, blob_type))
557 die("unable to read blob object %s", sha1_to_hex(sha1));
558 mm->size = size;
559 }
560
561 static struct merge_file_info merge_file(struct diff_filespec *o,
562 struct diff_filespec *a, struct diff_filespec *b,
563 const char *branch1, const char *branch2)
564 {
565 struct merge_file_info result;
566 result.merge = 0;
567 result.clean = 1;
568
569 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
570 result.clean = 0;
571 if (S_ISREG(a->mode)) {
572 result.mode = a->mode;
573 hashcpy(result.sha, a->sha1);
574 } else {
575 result.mode = b->mode;
576 hashcpy(result.sha, b->sha1);
577 }
578 } else {
579 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
580 result.merge = 1;
581
582 result.mode = a->mode == o->mode ? b->mode: a->mode;
583
584 if (sha_eq(a->sha1, o->sha1))
585 hashcpy(result.sha, b->sha1);
586 else if (sha_eq(b->sha1, o->sha1))
587 hashcpy(result.sha, a->sha1);
588 else if (S_ISREG(a->mode)) {
589 mmfile_t orig, src1, src2;
590 mmbuffer_t result_buf;
591 xpparam_t xpp;
592 char *name1, *name2;
593 int merge_status;
594
595 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
596 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
597
598 fill_mm(o->sha1, &orig);
599 fill_mm(a->sha1, &src1);
600 fill_mm(b->sha1, &src2);
601
602 memset(&xpp, 0, sizeof(xpp));
603 merge_status = xdl_merge(&orig,
604 &src1, name1,
605 &src2, name2,
606 &xpp, XDL_MERGE_ZEALOUS,
607 &result_buf);
608 free(name1);
609 free(name2);
610 free(orig.ptr);
611 free(src1.ptr);
612 free(src2.ptr);
613
614 if ((merge_status < 0) || !result_buf.ptr)
615 die("Failed to execute internal merge");
616
617 if (write_sha1_file(result_buf.ptr, result_buf.size,
618 blob_type, result.sha))
619 die("Unable to add %s to database",
620 a->path);
621
622 free(result_buf.ptr);
623 result.clean = (merge_status == 0);
624 } else {
625 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
626 die("cannot merge modes?");
627
628 hashcpy(result.sha, a->sha1);
629
630 if (!sha_eq(a->sha1, b->sha1))
631 result.clean = 0;
632 }
633 }
634
635 return result;
636 }
637
638 static void conflict_rename_rename(struct rename *ren1,
639 const char *branch1,
640 struct rename *ren2,
641 const char *branch2)
642 {
643 char *del[2];
644 int delp = 0;
645 const char *ren1_dst = ren1->pair->two->path;
646 const char *ren2_dst = ren2->pair->two->path;
647 const char *dst_name1 = ren1_dst;
648 const char *dst_name2 = ren2_dst;
649 if (path_list_has_path(&current_directory_set, ren1_dst)) {
650 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
651 output(1, "%s is a directory in %s adding as %s instead",
652 ren1_dst, branch2, dst_name1);
653 remove_file(0, ren1_dst, 0);
654 }
655 if (path_list_has_path(&current_directory_set, ren2_dst)) {
656 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
657 output(1, "%s is a directory in %s adding as %s instead",
658 ren2_dst, branch1, dst_name2);
659 remove_file(0, ren2_dst, 0);
660 }
661 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
662 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
663 while (delp--)
664 free(del[delp]);
665 }
666
667 static void conflict_rename_dir(struct rename *ren1,
668 const char *branch1)
669 {
670 char *new_path = unique_path(ren1->pair->two->path, branch1);
671 output(1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
672 remove_file(0, ren1->pair->two->path, 0);
673 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
674 free(new_path);
675 }
676
677 static void conflict_rename_rename_2(struct rename *ren1,
678 const char *branch1,
679 struct rename *ren2,
680 const char *branch2)
681 {
682 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
683 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
684 output(1, "Renaming %s to %s and %s to %s instead",
685 ren1->pair->one->path, new_path1,
686 ren2->pair->one->path, new_path2);
687 remove_file(0, ren1->pair->two->path, 0);
688 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
689 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
690 free(new_path2);
691 free(new_path1);
692 }
693
694 static int process_renames(struct path_list *a_renames,
695 struct path_list *b_renames,
696 const char *a_branch,
697 const char *b_branch)
698 {
699 int clean_merge = 1, i, j;
700 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
701 const struct rename *sre;
702
703 for (i = 0; i < a_renames->nr; i++) {
704 sre = a_renames->items[i].util;
705 path_list_insert(sre->pair->two->path, &a_by_dst)->util
706 = sre->dst_entry;
707 }
708 for (i = 0; i < b_renames->nr; i++) {
709 sre = b_renames->items[i].util;
710 path_list_insert(sre->pair->two->path, &b_by_dst)->util
711 = sre->dst_entry;
712 }
713
714 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
715 int compare;
716 char *src;
717 struct path_list *renames1, *renames2, *renames2Dst;
718 struct rename *ren1 = NULL, *ren2 = NULL;
719 const char *branch1, *branch2;
720 const char *ren1_src, *ren1_dst;
721
722 if (i >= a_renames->nr) {
723 compare = 1;
724 ren2 = b_renames->items[j++].util;
725 } else if (j >= b_renames->nr) {
726 compare = -1;
727 ren1 = a_renames->items[i++].util;
728 } else {
729 compare = strcmp(a_renames->items[i].path,
730 b_renames->items[j].path);
731 if (compare <= 0)
732 ren1 = a_renames->items[i++].util;
733 if (compare >= 0)
734 ren2 = b_renames->items[j++].util;
735 }
736
737 /* TODO: refactor, so that 1/2 are not needed */
738 if (ren1) {
739 renames1 = a_renames;
740 renames2 = b_renames;
741 renames2Dst = &b_by_dst;
742 branch1 = a_branch;
743 branch2 = b_branch;
744 } else {
745 struct rename *tmp;
746 renames1 = b_renames;
747 renames2 = a_renames;
748 renames2Dst = &a_by_dst;
749 branch1 = b_branch;
750 branch2 = a_branch;
751 tmp = ren2;
752 ren2 = ren1;
753 ren1 = tmp;
754 }
755 src = ren1->pair->one->path;
756
757 ren1->dst_entry->processed = 1;
758 ren1->src_entry->processed = 1;
759
760 if (ren1->processed)
761 continue;
762 ren1->processed = 1;
763
764 ren1_src = ren1->pair->one->path;
765 ren1_dst = ren1->pair->two->path;
766
767 if (ren2) {
768 const char *ren2_src = ren2->pair->one->path;
769 const char *ren2_dst = ren2->pair->two->path;
770 /* Renamed in 1 and renamed in 2 */
771 if (strcmp(ren1_src, ren2_src) != 0)
772 die("ren1.src != ren2.src");
773 ren2->dst_entry->processed = 1;
774 ren2->processed = 1;
775 if (strcmp(ren1_dst, ren2_dst) != 0) {
776 clean_merge = 0;
777 output(1, "CONFLICT (rename/rename): "
778 "Rename %s->%s in branch %s "
779 "rename %s->%s in %s",
780 src, ren1_dst, branch1,
781 src, ren2_dst, branch2);
782 conflict_rename_rename(ren1, branch1, ren2, branch2);
783 } else {
784 struct merge_file_info mfi;
785 remove_file(1, ren1_src, 1);
786 mfi = merge_file(ren1->pair->one,
787 ren1->pair->two,
788 ren2->pair->two,
789 branch1,
790 branch2);
791 if (mfi.merge || !mfi.clean)
792 output(1, "Renaming %s->%s", src, ren1_dst);
793
794 if (mfi.merge)
795 output(2, "Auto-merging %s", ren1_dst);
796
797 if (!mfi.clean) {
798 output(1, "CONFLICT (content): merge conflict in %s",
799 ren1_dst);
800 clean_merge = 0;
801
802 if (!index_only)
803 update_stages(ren1_dst,
804 ren1->pair->one,
805 ren1->pair->two,
806 ren2->pair->two,
807 1 /* clear */);
808 }
809 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
810 }
811 } else {
812 /* Renamed in 1, maybe changed in 2 */
813 struct path_list_item *item;
814 /* we only use sha1 and mode of these */
815 struct diff_filespec src_other, dst_other;
816 int try_merge, stage = a_renames == renames1 ? 3: 2;
817
818 remove_file(1, ren1_src, index_only);
819
820 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
821 src_other.mode = ren1->src_entry->stages[stage].mode;
822 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
823 dst_other.mode = ren1->dst_entry->stages[stage].mode;
824
825 try_merge = 0;
826
827 if (path_list_has_path(&current_directory_set, ren1_dst)) {
828 clean_merge = 0;
829 output(1, "CONFLICT (rename/directory): Rename %s->%s in %s "
830 " directory %s added in %s",
831 ren1_src, ren1_dst, branch1,
832 ren1_dst, branch2);
833 conflict_rename_dir(ren1, branch1);
834 } else if (sha_eq(src_other.sha1, null_sha1)) {
835 clean_merge = 0;
836 output(1, "CONFLICT (rename/delete): Rename %s->%s in %s "
837 "and deleted in %s",
838 ren1_src, ren1_dst, branch1,
839 branch2);
840 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
841 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
842 const char *new_path;
843 clean_merge = 0;
844 try_merge = 1;
845 output(1, "CONFLICT (rename/add): Rename %s->%s in %s. "
846 "%s added in %s",
847 ren1_src, ren1_dst, branch1,
848 ren1_dst, branch2);
849 new_path = unique_path(ren1_dst, branch2);
850 output(1, "Adding as %s instead", new_path);
851 update_file(0, dst_other.sha1, dst_other.mode, new_path);
852 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
853 ren2 = item->util;
854 clean_merge = 0;
855 ren2->processed = 1;
856 output(1, "CONFLICT (rename/rename): Rename %s->%s in %s. "
857 "Rename %s->%s in %s",
858 ren1_src, ren1_dst, branch1,
859 ren2->pair->one->path, ren2->pair->two->path, branch2);
860 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
861 } else
862 try_merge = 1;
863
864 if (try_merge) {
865 struct diff_filespec *o, *a, *b;
866 struct merge_file_info mfi;
867 src_other.path = (char *)ren1_src;
868
869 o = ren1->pair->one;
870 if (a_renames == renames1) {
871 a = ren1->pair->two;
872 b = &src_other;
873 } else {
874 b = ren1->pair->two;
875 a = &src_other;
876 }
877 mfi = merge_file(o, a, b,
878 a_branch, b_branch);
879
880 if (mfi.merge || !mfi.clean)
881 output(1, "Renaming %s => %s", ren1_src, ren1_dst);
882 if (mfi.merge)
883 output(2, "Auto-merging %s", ren1_dst);
884 if (!mfi.clean) {
885 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
886 ren1_dst);
887 clean_merge = 0;
888
889 if (!index_only)
890 update_stages(ren1_dst,
891 o, a, b, 1);
892 }
893 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
894 }
895 }
896 }
897 path_list_clear(&a_by_dst, 0);
898 path_list_clear(&b_by_dst, 0);
899
900 return clean_merge;
901 }
902
903 static unsigned char *has_sha(const unsigned char *sha)
904 {
905 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
906 }
907
908 /* Per entry merge function */
909 static int process_entry(const char *path, struct stage_data *entry,
910 const char *branch1,
911 const char *branch2)
912 {
913 /*
914 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
915 print_index_entry("\tpath: ", entry);
916 */
917 int clean_merge = 1;
918 unsigned char *o_sha = has_sha(entry->stages[1].sha);
919 unsigned char *a_sha = has_sha(entry->stages[2].sha);
920 unsigned char *b_sha = has_sha(entry->stages[3].sha);
921 unsigned o_mode = entry->stages[1].mode;
922 unsigned a_mode = entry->stages[2].mode;
923 unsigned b_mode = entry->stages[3].mode;
924
925 if (o_sha && (!a_sha || !b_sha)) {
926 /* Case A: Deleted in one */
927 if ((!a_sha && !b_sha) ||
928 (sha_eq(a_sha, o_sha) && !b_sha) ||
929 (!a_sha && sha_eq(b_sha, o_sha))) {
930 /* Deleted in both or deleted in one and
931 * unchanged in the other */
932 if (a_sha)
933 output(2, "Removing %s", path);
934 /* do not touch working file if it did not exist */
935 remove_file(1, path, !a_sha);
936 } else {
937 /* Deleted in one and changed in the other */
938 clean_merge = 0;
939 if (!a_sha) {
940 output(1, "CONFLICT (delete/modify): %s deleted in %s "
941 "and modified in %s. Version %s of %s left in tree.",
942 path, branch1,
943 branch2, branch2, path);
944 update_file(0, b_sha, b_mode, path);
945 } else {
946 output(1, "CONFLICT (delete/modify): %s deleted in %s "
947 "and modified in %s. Version %s of %s left in tree.",
948 path, branch2,
949 branch1, branch1, path);
950 update_file(0, a_sha, a_mode, path);
951 }
952 }
953
954 } else if ((!o_sha && a_sha && !b_sha) ||
955 (!o_sha && !a_sha && b_sha)) {
956 /* Case B: Added in one. */
957 const char *add_branch;
958 const char *other_branch;
959 unsigned mode;
960 const unsigned char *sha;
961 const char *conf;
962
963 if (a_sha) {
964 add_branch = branch1;
965 other_branch = branch2;
966 mode = a_mode;
967 sha = a_sha;
968 conf = "file/directory";
969 } else {
970 add_branch = branch2;
971 other_branch = branch1;
972 mode = b_mode;
973 sha = b_sha;
974 conf = "directory/file";
975 }
976 if (path_list_has_path(&current_directory_set, path)) {
977 const char *new_path = unique_path(path, add_branch);
978 clean_merge = 0;
979 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
980 "Adding %s as %s",
981 conf, path, other_branch, path, new_path);
982 remove_file(0, path, 0);
983 update_file(0, sha, mode, new_path);
984 } else {
985 output(2, "Adding %s", path);
986 update_file(1, sha, mode, path);
987 }
988 } else if (a_sha && b_sha) {
989 /* Case C: Added in both (check for same permissions) and */
990 /* case D: Modified in both, but differently. */
991 const char *reason = "content";
992 struct merge_file_info mfi;
993 struct diff_filespec o, a, b;
994
995 if (!o_sha) {
996 reason = "add/add";
997 o_sha = (unsigned char *)null_sha1;
998 }
999 output(2, "Auto-merging %s", path);
1000 o.path = a.path = b.path = (char *)path;
1001 hashcpy(o.sha1, o_sha);
1002 o.mode = o_mode;
1003 hashcpy(a.sha1, a_sha);
1004 a.mode = a_mode;
1005 hashcpy(b.sha1, b_sha);
1006 b.mode = b_mode;
1007
1008 mfi = merge_file(&o, &a, &b,
1009 branch1, branch2);
1010
1011 if (mfi.clean)
1012 update_file(1, mfi.sha, mfi.mode, path);
1013 else {
1014 clean_merge = 0;
1015 output(1, "CONFLICT (%s): Merge conflict in %s",
1016 reason, path);
1017
1018 if (index_only)
1019 update_file(0, mfi.sha, mfi.mode, path);
1020 else
1021 update_file_flags(mfi.sha, mfi.mode, path,
1022 0 /* update_cache */, 1 /* update_working_directory */);
1023 }
1024 } else
1025 die("Fatal merge failure, shouldn't happen.");
1026
1027 return clean_merge;
1028 }
1029
1030 static int merge_trees(struct tree *head,
1031 struct tree *merge,
1032 struct tree *common,
1033 const char *branch1,
1034 const char *branch2,
1035 struct tree **result)
1036 {
1037 int code, clean;
1038 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1039 output(0, "Already uptodate!");
1040 *result = head;
1041 return 1;
1042 }
1043
1044 code = git_merge_trees(index_only, common, head, merge);
1045
1046 if (code != 0)
1047 die("merging of trees %s and %s failed",
1048 sha1_to_hex(head->object.sha1),
1049 sha1_to_hex(merge->object.sha1));
1050
1051 if (unmerged_index()) {
1052 struct path_list *entries, *re_head, *re_merge;
1053 int i;
1054 path_list_clear(&current_file_set, 1);
1055 path_list_clear(&current_directory_set, 1);
1056 get_files_dirs(head);
1057 get_files_dirs(merge);
1058
1059 entries = get_unmerged();
1060 re_head = get_renames(head, common, head, merge, entries);
1061 re_merge = get_renames(merge, common, head, merge, entries);
1062 clean = process_renames(re_head, re_merge,
1063 branch1, branch2);
1064 for (i = 0; i < entries->nr; i++) {
1065 const char *path = entries->items[i].path;
1066 struct stage_data *e = entries->items[i].util;
1067 if (e->processed)
1068 continue;
1069 if (!process_entry(path, e, branch1, branch2))
1070 clean = 0;
1071 }
1072
1073 path_list_clear(re_merge, 0);
1074 path_list_clear(re_head, 0);
1075 path_list_clear(entries, 1);
1076
1077 }
1078 else
1079 clean = 1;
1080
1081 if (index_only)
1082 *result = git_write_tree();
1083
1084 return clean;
1085 }
1086
1087 static struct commit_list *reverse_commit_list(struct commit_list *list)
1088 {
1089 struct commit_list *next = NULL, *current, *backup;
1090 for (current = list; current; current = backup) {
1091 backup = current->next;
1092 current->next = next;
1093 next = current;
1094 }
1095 return next;
1096 }
1097
1098 /*
1099 * Merge the commits h1 and h2, return the resulting virtual
1100 * commit object and a flag indicating the cleaness of the merge.
1101 */
1102 static int merge(struct commit *h1,
1103 struct commit *h2,
1104 const char *branch1,
1105 const char *branch2,
1106 struct commit_list *ca,
1107 struct commit **result)
1108 {
1109 struct commit_list *iter;
1110 struct commit *merged_common_ancestors;
1111 struct tree *mrtree;
1112 int clean;
1113
1114 if (show(4)) {
1115 output(4, "Merging:");
1116 output_commit_title(h1);
1117 output_commit_title(h2);
1118 }
1119
1120 if (!ca) {
1121 ca = get_merge_bases(h1, h2, 1);
1122 ca = reverse_commit_list(ca);
1123 }
1124
1125 if (show(5)) {
1126 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1127 for (iter = ca; iter; iter = iter->next)
1128 output_commit_title(iter->item);
1129 }
1130
1131 merged_common_ancestors = pop_commit(&ca);
1132 if (merged_common_ancestors == NULL) {
1133 /* if there is no common ancestor, make an empty tree */
1134 struct tree *tree = xcalloc(1, sizeof(struct tree));
1135
1136 tree->object.parsed = 1;
1137 tree->object.type = OBJ_TREE;
1138 write_sha1_file(NULL, 0, tree_type, tree->object.sha1);
1139 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1140 }
1141
1142 for (iter = ca; iter; iter = iter->next) {
1143 call_depth++;
1144 /*
1145 * When the merge fails, the result contains files
1146 * with conflict markers. The cleanness flag is
1147 * ignored, it was never acutally used, as result of
1148 * merge_trees has always overwritten it: the commited
1149 * "conflicts" were already resolved.
1150 */
1151 discard_cache();
1152 merge(merged_common_ancestors, iter->item,
1153 "Temporary merge branch 1",
1154 "Temporary merge branch 2",
1155 NULL,
1156 &merged_common_ancestors);
1157 call_depth--;
1158
1159 if (!merged_common_ancestors)
1160 die("merge returned no commit");
1161 }
1162
1163 discard_cache();
1164 if (!call_depth) {
1165 read_cache();
1166 index_only = 0;
1167 } else
1168 index_only = 1;
1169
1170 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1171 branch1, branch2, &mrtree);
1172
1173 if (index_only) {
1174 *result = make_virtual_commit(mrtree, "merged tree");
1175 commit_list_insert(h1, &(*result)->parents);
1176 commit_list_insert(h2, &(*result)->parents->next);
1177 }
1178 return clean;
1179 }
1180
1181 static const char *better_branch_name(const char *branch)
1182 {
1183 static char githead_env[8 + 40 + 1];
1184 char *name;
1185
1186 if (strlen(branch) != 40)
1187 return branch;
1188 sprintf(githead_env, "GITHEAD_%s", branch);
1189 name = getenv(githead_env);
1190 return name ? name : branch;
1191 }
1192
1193 static struct commit *get_ref(const char *ref)
1194 {
1195 unsigned char sha1[20];
1196 struct object *object;
1197
1198 if (get_sha1(ref, sha1))
1199 die("Could not resolve ref '%s'", ref);
1200 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1201 if (object->type == OBJ_TREE)
1202 return make_virtual_commit((struct tree*)object,
1203 better_branch_name(ref));
1204 if (object->type != OBJ_COMMIT)
1205 return NULL;
1206 if (parse_commit((struct commit *)object))
1207 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1208 return (struct commit *)object;
1209 }
1210
1211 static int merge_config(const char *var, const char *value)
1212 {
1213 if (!strcasecmp(var, "merge.verbosity")) {
1214 verbosity = git_config_int(var, value);
1215 return 0;
1216 }
1217 return git_default_config(var, value);
1218 }
1219
1220 int main(int argc, char *argv[])
1221 {
1222 static const char *bases[20];
1223 static unsigned bases_count = 0;
1224 int i, clean;
1225 const char *branch1, *branch2;
1226 struct commit *result, *h1, *h2;
1227 struct commit_list *ca = NULL;
1228 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1229 int index_fd;
1230
1231 git_config(merge_config);
1232 if (getenv("GIT_MERGE_VERBOSITY"))
1233 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1234
1235 if (argc < 4)
1236 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1237
1238 for (i = 1; i < argc; ++i) {
1239 if (!strcmp(argv[i], "--"))
1240 break;
1241 if (bases_count < sizeof(bases)/sizeof(*bases))
1242 bases[bases_count++] = argv[i];
1243 }
1244 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1245 die("Not handling anything other than two heads merge.");
1246
1247 branch1 = argv[++i];
1248 branch2 = argv[++i];
1249
1250 h1 = get_ref(branch1);
1251 h2 = get_ref(branch2);
1252
1253 branch1 = better_branch_name(branch1);
1254 branch2 = better_branch_name(branch2);
1255 if (show(3))
1256 printf("Merging %s with %s\n", branch1, branch2);
1257
1258 index_fd = hold_lock_file_for_update(lock, get_index_file(), 1);
1259
1260 for (i = 0; i < bases_count; i++) {
1261 struct commit *ancestor = get_ref(bases[i]);
1262 ca = commit_list_insert(ancestor, &ca);
1263 }
1264 clean = merge(h1, h2, branch1, branch2, ca, &result);
1265
1266 if (active_cache_changed &&
1267 (write_cache(index_fd, active_cache, active_nr) ||
1268 close(index_fd) || commit_lock_file(lock)))
1269 die ("unable to write %s", get_index_file());
1270
1271 return clean ? 0: 1;
1272 }