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Merge branch 'maint'
[git.git] / builtin-merge-recursive.c
blob5a0a7b529765fa229318af86a68e58a92e287154
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 "builtin.h"
11 #include "tree-walk.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "tag.h"
15 #include "unpack-trees.h"
16 #include "path-list.h"
17 #include "xdiff-interface.h"
18 #include "ll-merge.h"
19 #include "interpolate.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
22
23 static int subtree_merge;
24
25 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
26 {
27 unsigned char shifted[20];
28
29 /*
30 * NEEDSWORK: this limits the recursion depth to hardcoded
31 * value '2' to avoid excessive overhead.
32 */
33 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
34 if (!hashcmp(two->object.sha1, shifted))
35 return two;
36 return lookup_tree(shifted);
37 }
38
39 /*
40 * A virtual commit has
41 * - (const char *)commit->util set to the name, and
42 * - *(int *)commit->object.sha1 set to the virtual id.
43 */
44
45 static unsigned commit_list_count(const struct commit_list *l)
46 {
47 unsigned c = 0;
48 for (; l; l = l->next )
49 c++;
50 return c;
51 }
52
53 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
54 {
55 struct commit *commit = xcalloc(1, sizeof(struct commit));
56 static unsigned virtual_id = 1;
57 commit->tree = tree;
58 commit->util = (void*)comment;
59 *(int*)commit->object.sha1 = virtual_id++;
60 /* avoid warnings */
61 commit->object.parsed = 1;
62 return commit;
63 }
64
65 /*
66 * Since we use get_tree_entry(), which does not put the read object into
67 * the object pool, we cannot rely on a == b.
68 */
69 static int sha_eq(const unsigned char *a, const unsigned char *b)
70 {
71 if (!a && !b)
72 return 2;
73 return a && b && hashcmp(a, b) == 0;
74 }
75
76 /*
77 * Since we want to write the index eventually, we cannot reuse the index
78 * for these (temporary) data.
79 */
80 struct stage_data
81 {
82 struct
83 {
84 unsigned mode;
85 unsigned char sha[20];
86 } stages[4];
87 unsigned processed:1;
88 };
89
90 static struct path_list current_file_set = {NULL, 0, 0, 1};
91 static struct path_list current_directory_set = {NULL, 0, 0, 1};
92
93 static int call_depth = 0;
94 static int verbosity = 2;
95 static int rename_limit = -1;
96 static int buffer_output = 1;
97 static struct strbuf obuf = STRBUF_INIT;
98
99 static int show(int v)
100 {
101 return (!call_depth && verbosity >= v) || verbosity >= 5;
102 }
103
104 static void flush_output(void)
105 {
106 if (obuf.len) {
107 fputs(obuf.buf, stdout);
108 strbuf_reset(&obuf);
109 }
110 }
111
112 static void output(int v, const char *fmt, ...)
113 {
114 int len;
115 va_list ap;
116
117 if (!show(v))
118 return;
119
120 strbuf_grow(&obuf, call_depth * 2 + 2);
121 memset(obuf.buf + obuf.len, ' ', call_depth * 2);
122 strbuf_setlen(&obuf, obuf.len + call_depth * 2);
123
124 va_start(ap, fmt);
125 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
126 va_end(ap);
127
128 if (len < 0)
129 len = 0;
130 if (len >= strbuf_avail(&obuf)) {
131 strbuf_grow(&obuf, len + 2);
132 va_start(ap, fmt);
133 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
134 va_end(ap);
135 if (len >= strbuf_avail(&obuf)) {
136 die("this should not happen, your snprintf is broken");
137 }
138 }
139 strbuf_setlen(&obuf, obuf.len + len);
140 strbuf_add(&obuf, "\n", 1);
141 if (!buffer_output)
142 flush_output();
143 }
144
145 static void output_commit_title(struct commit *commit)
146 {
147 int i;
148 flush_output();
149 for (i = call_depth; i--;)
150 fputs(" ", stdout);
151 if (commit->util)
152 printf("virtual %s\n", (char *)commit->util);
153 else {
154 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
155 if (parse_commit(commit) != 0)
156 printf("(bad commit)\n");
157 else {
158 const char *s;
159 int len;
160 for (s = commit->buffer; *s; s++)
161 if (*s == '\n' && s[1] == '\n') {
162 s += 2;
163 break;
164 }
165 for (len = 0; s[len] && '\n' != s[len]; len++)
166 ; /* do nothing */
167 printf("%.*s\n", len, s);
168 }
169 }
170 }
171
172 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
173 const char *path, int stage, int refresh, int options)
174 {
175 struct cache_entry *ce;
176 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
177 if (!ce)
178 return error("addinfo_cache failed for path '%s'", path);
179 return add_cache_entry(ce, options);
180 }
181
182 /*
183 * This is a global variable which is used in a number of places but
184 * only written to in the 'merge' function.
185 *
186 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
187 * don't update the working directory.
188 * 0 => Leave unmerged entries in the cache and update
189 * the working directory.
190 */
191 static int index_only = 0;
192
193 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
194 {
195 parse_tree(tree);
196 init_tree_desc(desc, tree->buffer, tree->size);
197 }
198
199 static int git_merge_trees(int index_only,
200 struct tree *common,
201 struct tree *head,
202 struct tree *merge)
203 {
204 int rc;
205 struct tree_desc t[3];
206 struct unpack_trees_options opts;
207
208 memset(&opts, 0, sizeof(opts));
209 if (index_only)
210 opts.index_only = 1;
211 else
212 opts.update = 1;
213 opts.merge = 1;
214 opts.head_idx = 2;
215 opts.fn = threeway_merge;
216
217 init_tree_desc_from_tree(t+0, common);
218 init_tree_desc_from_tree(t+1, head);
219 init_tree_desc_from_tree(t+2, merge);
220
221 rc = unpack_trees(3, t, &opts);
222 cache_tree_free(&active_cache_tree);
223 return rc;
224 }
225
226 struct tree *write_tree_from_memory(void)
227 {
228 struct tree *result = NULL;
229
230 if (unmerged_cache()) {
231 int i;
232 output(0, "There are unmerged index entries:");
233 for (i = 0; i < active_nr; i++) {
234 struct cache_entry *ce = active_cache[i];
235 if (ce_stage(ce))
236 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
237 }
238 return NULL;
239 }
240
241 if (!active_cache_tree)
242 active_cache_tree = cache_tree();
243
244 if (!cache_tree_fully_valid(active_cache_tree) &&
245 cache_tree_update(active_cache_tree,
246 active_cache, active_nr, 0, 0) < 0)
247 die("error building trees");
248
249 result = lookup_tree(active_cache_tree->sha1);
250
251 return result;
252 }
253
254 static int save_files_dirs(const unsigned char *sha1,
255 const char *base, int baselen, const char *path,
256 unsigned int mode, int stage)
257 {
258 int len = strlen(path);
259 char *newpath = xmalloc(baselen + len + 1);
260 memcpy(newpath, base, baselen);
261 memcpy(newpath + baselen, path, len);
262 newpath[baselen + len] = '\0';
263
264 if (S_ISDIR(mode))
265 path_list_insert(newpath, &current_directory_set);
266 else
267 path_list_insert(newpath, &current_file_set);
268 free(newpath);
269
270 return READ_TREE_RECURSIVE;
271 }
272
273 static int get_files_dirs(struct tree *tree)
274 {
275 int n;
276 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
277 return 0;
278 n = current_file_set.nr + current_directory_set.nr;
279 return n;
280 }
281
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 path_list *entries)
289 {
290 struct path_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 = path_list_insert(path, entries);
299 item->util = e;
300 return e;
301 }
302
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 path_list *get_unmerged(void)
308 {
309 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
310 int i;
311
312 unmerged->strdup_paths = 1;
313
314 for (i = 0; i < active_nr; i++) {
315 struct path_list_item *item;
316 struct stage_data *e;
317 struct cache_entry *ce = active_cache[i];
318 if (!ce_stage(ce))
319 continue;
320
321 item = path_list_lookup(ce->name, unmerged);
322 if (!item) {
323 item = path_list_insert(ce->name, unmerged);
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 }
330
331 return unmerged;
332 }
333
334 struct rename
335 {
336 struct diff_filepair *pair;
337 struct stage_data *src_entry;
338 struct stage_data *dst_entry;
339 unsigned processed:1;
340 };
341
342 /*
343 * Get information of all renames which occurred between 'o_tree' and
344 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
345 * 'b_tree') to be able to associate the correct cache entries with
346 * the rename information. 'tree' is always equal to either a_tree or b_tree.
347 */
348 static struct path_list *get_renames(struct tree *tree,
349 struct tree *o_tree,
350 struct tree *a_tree,
351 struct tree *b_tree,
352 struct path_list *entries)
353 {
354 int i;
355 struct path_list *renames;
356 struct diff_options opts;
357
358 renames = xcalloc(1, sizeof(struct path_list));
359 diff_setup(&opts);
360 DIFF_OPT_SET(&opts, RECURSIVE);
361 opts.detect_rename = DIFF_DETECT_RENAME;
362 opts.rename_limit = rename_limit;
363 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
364 if (diff_setup_done(&opts) < 0)
365 die("diff setup failed");
366 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
367 diffcore_std(&opts);
368 for (i = 0; i < diff_queued_diff.nr; ++i) {
369 struct path_list_item *item;
370 struct rename *re;
371 struct diff_filepair *pair = diff_queued_diff.queue[i];
372 if (pair->status != 'R') {
373 diff_free_filepair(pair);
374 continue;
375 }
376 re = xmalloc(sizeof(*re));
377 re->processed = 0;
378 re->pair = pair;
379 item = path_list_lookup(re->pair->one->path, entries);
380 if (!item)
381 re->src_entry = insert_stage_data(re->pair->one->path,
382 o_tree, a_tree, b_tree, entries);
383 else
384 re->src_entry = item->util;
385
386 item = path_list_lookup(re->pair->two->path, entries);
387 if (!item)
388 re->dst_entry = insert_stage_data(re->pair->two->path,
389 o_tree, a_tree, b_tree, entries);
390 else
391 re->dst_entry = item->util;
392 item = path_list_insert(pair->one->path, renames);
393 item->util = re;
394 }
395 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
396 diff_queued_diff.nr = 0;
397 diff_flush(&opts);
398 return renames;
399 }
400
401 static int update_stages(const char *path, struct diff_filespec *o,
402 struct diff_filespec *a, struct diff_filespec *b,
403 int clear)
404 {
405 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
406 if (clear)
407 if (remove_file_from_cache(path))
408 return -1;
409 if (o)
410 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
411 return -1;
412 if (a)
413 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
414 return -1;
415 if (b)
416 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
417 return -1;
418 return 0;
419 }
420
421 static int remove_path(const char *name)
422 {
423 int ret;
424 char *slash, *dirs;
425
426 ret = unlink(name);
427 if (ret)
428 return ret;
429 dirs = xstrdup(name);
430 while ((slash = strrchr(name, '/'))) {
431 *slash = '\0';
432 if (rmdir(name) != 0)
433 break;
434 }
435 free(dirs);
436 return ret;
437 }
438
439 static int remove_file(int clean, const char *path, int no_wd)
440 {
441 int update_cache = index_only || clean;
442 int update_working_directory = !index_only && !no_wd;
443
444 if (update_cache) {
445 if (remove_file_from_cache(path))
446 return -1;
447 }
448 if (update_working_directory) {
449 unlink(path);
450 if (errno != ENOENT || errno != EISDIR)
451 return -1;
452 remove_path(path);
453 }
454 return 0;
455 }
456
457 static char *unique_path(const char *path, const char *branch)
458 {
459 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
460 int suffix = 0;
461 struct stat st;
462 char *p = newpath + strlen(path);
463 strcpy(newpath, path);
464 *(p++) = '~';
465 strcpy(p, branch);
466 for (; *p; ++p)
467 if ('/' == *p)
468 *p = '_';
469 while (path_list_has_path(&current_file_set, newpath) ||
470 path_list_has_path(&current_directory_set, newpath) ||
471 lstat(newpath, &st) == 0)
472 sprintf(p, "_%d", suffix++);
473
474 path_list_insert(newpath, &current_file_set);
475 return newpath;
476 }
477
478 static int mkdir_p(const char *path, unsigned long mode)
479 {
480 /* path points to cache entries, so xstrdup before messing with it */
481 char *buf = xstrdup(path);
482 int result = safe_create_leading_directories(buf);
483 free(buf);
484 return result;
485 }
486
487 static void flush_buffer(int fd, const char *buf, unsigned long size)
488 {
489 while (size > 0) {
490 long ret = write_in_full(fd, buf, size);
491 if (ret < 0) {
492 /* Ignore epipe */
493 if (errno == EPIPE)
494 break;
495 die("merge-recursive: %s", strerror(errno));
496 } else if (!ret) {
497 die("merge-recursive: disk full?");
498 }
499 size -= ret;
500 buf += ret;
501 }
502 }
503
504 static int make_room_for_path(const char *path)
505 {
506 int status;
507 const char *msg = "failed to create path '%s'%s";
508
509 status = mkdir_p(path, 0777);
510 if (status) {
511 if (status == -3) {
512 /* something else exists */
513 error(msg, path, ": perhaps a D/F conflict?");
514 return -1;
515 }
516 die(msg, path, "");
517 }
518
519 /* Successful unlink is good.. */
520 if (!unlink(path))
521 return 0;
522 /* .. and so is no existing file */
523 if (errno == ENOENT)
524 return 0;
525 /* .. but not some other error (who really cares what?) */
526 return error(msg, path, ": perhaps a D/F conflict?");
527 }
528
529 static void update_file_flags(const unsigned char *sha,
530 unsigned mode,
531 const char *path,
532 int update_cache,
533 int update_wd)
534 {
535 if (index_only)
536 update_wd = 0;
537
538 if (update_wd) {
539 enum object_type type;
540 void *buf;
541 unsigned long size;
542
543 if (S_ISGITLINK(mode))
544 die("cannot read object %s '%s': It is a submodule!",
545 sha1_to_hex(sha), path);
546
547 buf = read_sha1_file(sha, &type, &size);
548 if (!buf)
549 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
550 if (type != OBJ_BLOB)
551 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
552
553 if (make_room_for_path(path) < 0) {
554 update_wd = 0;
555 goto update_index;
556 }
557 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
558 int fd;
559 if (mode & 0100)
560 mode = 0777;
561 else
562 mode = 0666;
563 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
564 if (fd < 0)
565 die("failed to open %s: %s", path, strerror(errno));
566 flush_buffer(fd, buf, size);
567 close(fd);
568 } else if (S_ISLNK(mode)) {
569 char *lnk = xmemdupz(buf, size);
570 mkdir_p(path, 0777);
571 unlink(path);
572 symlink(lnk, path);
573 free(lnk);
574 } else
575 die("do not know what to do with %06o %s '%s'",
576 mode, sha1_to_hex(sha), path);
577 }
578 update_index:
579 if (update_cache)
580 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
581 }
582
583 static void update_file(int clean,
584 const unsigned char *sha,
585 unsigned mode,
586 const char *path)
587 {
588 update_file_flags(sha, mode, path, index_only || clean, !index_only);
589 }
590
591 /* Low level file merging, update and removal */
592
593 struct merge_file_info
594 {
595 unsigned char sha[20];
596 unsigned mode;
597 unsigned clean:1,
598 merge:1;
599 };
600
601 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
602 {
603 unsigned long size;
604 enum object_type type;
605
606 if (!hashcmp(sha1, null_sha1)) {
607 mm->ptr = xstrdup("");
608 mm->size = 0;
609 return;
610 }
611
612 mm->ptr = read_sha1_file(sha1, &type, &size);
613 if (!mm->ptr || type != OBJ_BLOB)
614 die("unable to read blob object %s", sha1_to_hex(sha1));
615 mm->size = size;
616 }
617
618 static int merge_3way(mmbuffer_t *result_buf,
619 struct diff_filespec *o,
620 struct diff_filespec *a,
621 struct diff_filespec *b,
622 const char *branch1,
623 const char *branch2)
624 {
625 mmfile_t orig, src1, src2;
626 char *name1, *name2;
627 int merge_status;
628
629 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
630 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
631
632 fill_mm(o->sha1, &orig);
633 fill_mm(a->sha1, &src1);
634 fill_mm(b->sha1, &src2);
635
636 merge_status = ll_merge(result_buf, a->path, &orig,
637 &src1, name1, &src2, name2,
638 index_only);
639
640 free(name1);
641 free(name2);
642 free(orig.ptr);
643 free(src1.ptr);
644 free(src2.ptr);
645 return merge_status;
646 }
647
648 static struct merge_file_info merge_file(struct diff_filespec *o,
649 struct diff_filespec *a, struct diff_filespec *b,
650 const char *branch1, const char *branch2)
651 {
652 struct merge_file_info result;
653 result.merge = 0;
654 result.clean = 1;
655
656 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
657 result.clean = 0;
658 if (S_ISREG(a->mode)) {
659 result.mode = a->mode;
660 hashcpy(result.sha, a->sha1);
661 } else {
662 result.mode = b->mode;
663 hashcpy(result.sha, b->sha1);
664 }
665 } else {
666 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
667 result.merge = 1;
668
669 result.mode = a->mode == o->mode ? b->mode: a->mode;
670
671 if (sha_eq(a->sha1, o->sha1))
672 hashcpy(result.sha, b->sha1);
673 else if (sha_eq(b->sha1, o->sha1))
674 hashcpy(result.sha, a->sha1);
675 else if (S_ISREG(a->mode)) {
676 mmbuffer_t result_buf;
677 int merge_status;
678
679 merge_status = merge_3way(&result_buf, o, a, b,
680 branch1, branch2);
681
682 if ((merge_status < 0) || !result_buf.ptr)
683 die("Failed to execute internal merge");
684
685 if (write_sha1_file(result_buf.ptr, result_buf.size,
686 blob_type, result.sha))
687 die("Unable to add %s to database",
688 a->path);
689
690 free(result_buf.ptr);
691 result.clean = (merge_status == 0);
692 } else if (S_ISGITLINK(a->mode)) {
693 result.clean = 0;
694 hashcpy(result.sha, a->sha1);
695 } else if (S_ISLNK(a->mode)) {
696 hashcpy(result.sha, a->sha1);
697
698 if (!sha_eq(a->sha1, b->sha1))
699 result.clean = 0;
700 } else {
701 die("unsupported object type in the tree");
702 }
703 }
704
705 return result;
706 }
707
708 static void conflict_rename_rename(struct rename *ren1,
709 const char *branch1,
710 struct rename *ren2,
711 const char *branch2)
712 {
713 char *del[2];
714 int delp = 0;
715 const char *ren1_dst = ren1->pair->two->path;
716 const char *ren2_dst = ren2->pair->two->path;
717 const char *dst_name1 = ren1_dst;
718 const char *dst_name2 = ren2_dst;
719 if (path_list_has_path(&current_directory_set, ren1_dst)) {
720 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
721 output(1, "%s is a directory in %s added as %s instead",
722 ren1_dst, branch2, dst_name1);
723 remove_file(0, ren1_dst, 0);
724 }
725 if (path_list_has_path(&current_directory_set, ren2_dst)) {
726 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
727 output(1, "%s is a directory in %s added as %s instead",
728 ren2_dst, branch1, dst_name2);
729 remove_file(0, ren2_dst, 0);
730 }
731 if (index_only) {
732 remove_file_from_cache(dst_name1);
733 remove_file_from_cache(dst_name2);
734 /*
735 * Uncomment to leave the conflicting names in the resulting tree
736 *
737 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
738 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
739 */
740 } else {
741 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
742 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
743 }
744 while (delp--)
745 free(del[delp]);
746 }
747
748 static void conflict_rename_dir(struct rename *ren1,
749 const char *branch1)
750 {
751 char *new_path = unique_path(ren1->pair->two->path, branch1);
752 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
753 remove_file(0, ren1->pair->two->path, 0);
754 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
755 free(new_path);
756 }
757
758 static void conflict_rename_rename_2(struct rename *ren1,
759 const char *branch1,
760 struct rename *ren2,
761 const char *branch2)
762 {
763 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
764 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
765 output(1, "Renamed %s to %s and %s to %s instead",
766 ren1->pair->one->path, new_path1,
767 ren2->pair->one->path, new_path2);
768 remove_file(0, ren1->pair->two->path, 0);
769 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
770 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
771 free(new_path2);
772 free(new_path1);
773 }
774
775 static int process_renames(struct path_list *a_renames,
776 struct path_list *b_renames,
777 const char *a_branch,
778 const char *b_branch)
779 {
780 int clean_merge = 1, i, j;
781 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
782 const struct rename *sre;
783
784 for (i = 0; i < a_renames->nr; i++) {
785 sre = a_renames->items[i].util;
786 path_list_insert(sre->pair->two->path, &a_by_dst)->util
787 = sre->dst_entry;
788 }
789 for (i = 0; i < b_renames->nr; i++) {
790 sre = b_renames->items[i].util;
791 path_list_insert(sre->pair->two->path, &b_by_dst)->util
792 = sre->dst_entry;
793 }
794
795 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
796 int compare;
797 char *src;
798 struct path_list *renames1, *renames2, *renames2Dst;
799 struct rename *ren1 = NULL, *ren2 = NULL;
800 const char *branch1, *branch2;
801 const char *ren1_src, *ren1_dst;
802
803 if (i >= a_renames->nr) {
804 compare = 1;
805 ren2 = b_renames->items[j++].util;
806 } else if (j >= b_renames->nr) {
807 compare = -1;
808 ren1 = a_renames->items[i++].util;
809 } else {
810 compare = strcmp(a_renames->items[i].path,
811 b_renames->items[j].path);
812 if (compare <= 0)
813 ren1 = a_renames->items[i++].util;
814 if (compare >= 0)
815 ren2 = b_renames->items[j++].util;
816 }
817
818 /* TODO: refactor, so that 1/2 are not needed */
819 if (ren1) {
820 renames1 = a_renames;
821 renames2 = b_renames;
822 renames2Dst = &b_by_dst;
823 branch1 = a_branch;
824 branch2 = b_branch;
825 } else {
826 struct rename *tmp;
827 renames1 = b_renames;
828 renames2 = a_renames;
829 renames2Dst = &a_by_dst;
830 branch1 = b_branch;
831 branch2 = a_branch;
832 tmp = ren2;
833 ren2 = ren1;
834 ren1 = tmp;
835 }
836 src = ren1->pair->one->path;
837
838 ren1->dst_entry->processed = 1;
839 ren1->src_entry->processed = 1;
840
841 if (ren1->processed)
842 continue;
843 ren1->processed = 1;
844
845 ren1_src = ren1->pair->one->path;
846 ren1_dst = ren1->pair->two->path;
847
848 if (ren2) {
849 const char *ren2_src = ren2->pair->one->path;
850 const char *ren2_dst = ren2->pair->two->path;
851 /* Renamed in 1 and renamed in 2 */
852 if (strcmp(ren1_src, ren2_src) != 0)
853 die("ren1.src != ren2.src");
854 ren2->dst_entry->processed = 1;
855 ren2->processed = 1;
856 if (strcmp(ren1_dst, ren2_dst) != 0) {
857 clean_merge = 0;
858 output(1, "CONFLICT (rename/rename): "
859 "Rename \"%s\"->\"%s\" in branch \"%s\" "
860 "rename \"%s\"->\"%s\" in \"%s\"%s",
861 src, ren1_dst, branch1,
862 src, ren2_dst, branch2,
863 index_only ? " (left unresolved)": "");
864 if (index_only) {
865 remove_file_from_cache(src);
866 update_file(0, ren1->pair->one->sha1,
867 ren1->pair->one->mode, src);
868 }
869 conflict_rename_rename(ren1, branch1, ren2, branch2);
870 } else {
871 struct merge_file_info mfi;
872 remove_file(1, ren1_src, 1);
873 mfi = merge_file(ren1->pair->one,
874 ren1->pair->two,
875 ren2->pair->two,
876 branch1,
877 branch2);
878 if (mfi.merge || !mfi.clean)
879 output(1, "Renamed %s->%s", src, ren1_dst);
880
881 if (mfi.merge)
882 output(2, "Auto-merged %s", ren1_dst);
883
884 if (!mfi.clean) {
885 output(1, "CONFLICT (content): merge conflict in %s",
886 ren1_dst);
887 clean_merge = 0;
888
889 if (!index_only)
890 update_stages(ren1_dst,
891 ren1->pair->one,
892 ren1->pair->two,
893 ren2->pair->two,
894 1 /* clear */);
895 }
896 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
897 }
898 } else {
899 /* Renamed in 1, maybe changed in 2 */
900 struct path_list_item *item;
901 /* we only use sha1 and mode of these */
902 struct diff_filespec src_other, dst_other;
903 int try_merge, stage = a_renames == renames1 ? 3: 2;
904
905 remove_file(1, ren1_src, index_only || stage == 3);
906
907 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
908 src_other.mode = ren1->src_entry->stages[stage].mode;
909 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
910 dst_other.mode = ren1->dst_entry->stages[stage].mode;
911
912 try_merge = 0;
913
914 if (path_list_has_path(&current_directory_set, ren1_dst)) {
915 clean_merge = 0;
916 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
917 " directory %s added in %s",
918 ren1_src, ren1_dst, branch1,
919 ren1_dst, branch2);
920 conflict_rename_dir(ren1, branch1);
921 } else if (sha_eq(src_other.sha1, null_sha1)) {
922 clean_merge = 0;
923 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
924 "and deleted in %s",
925 ren1_src, ren1_dst, branch1,
926 branch2);
927 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
928 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
929 const char *new_path;
930 clean_merge = 0;
931 try_merge = 1;
932 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
933 "%s added in %s",
934 ren1_src, ren1_dst, branch1,
935 ren1_dst, branch2);
936 new_path = unique_path(ren1_dst, branch2);
937 output(1, "Added as %s instead", new_path);
938 update_file(0, dst_other.sha1, dst_other.mode, new_path);
939 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
940 ren2 = item->util;
941 clean_merge = 0;
942 ren2->processed = 1;
943 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
944 "Renamed %s->%s in %s",
945 ren1_src, ren1_dst, branch1,
946 ren2->pair->one->path, ren2->pair->two->path, branch2);
947 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
948 } else
949 try_merge = 1;
950
951 if (try_merge) {
952 struct diff_filespec *o, *a, *b;
953 struct merge_file_info mfi;
954 src_other.path = (char *)ren1_src;
955
956 o = ren1->pair->one;
957 if (a_renames == renames1) {
958 a = ren1->pair->two;
959 b = &src_other;
960 } else {
961 b = ren1->pair->two;
962 a = &src_other;
963 }
964 mfi = merge_file(o, a, b,
965 a_branch, b_branch);
966
967 if (mfi.clean &&
968 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
969 mfi.mode == ren1->pair->two->mode)
970 /*
971 * This messaged is part of
972 * t6022 test. If you change
973 * it update the test too.
974 */
975 output(3, "Skipped %s (merged same as existing)", ren1_dst);
976 else {
977 if (mfi.merge || !mfi.clean)
978 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
979 if (mfi.merge)
980 output(2, "Auto-merged %s", ren1_dst);
981 if (!mfi.clean) {
982 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
983 ren1_dst);
984 clean_merge = 0;
985
986 if (!index_only)
987 update_stages(ren1_dst,
988 o, a, b, 1);
989 }
990 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
991 }
992 }
993 }
994 }
995 path_list_clear(&a_by_dst, 0);
996 path_list_clear(&b_by_dst, 0);
997
998 return clean_merge;
999 }
1000
1001 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1002 {
1003 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1004 }
1005
1006 /* Per entry merge function */
1007 static int process_entry(const char *path, struct stage_data *entry,
1008 const char *branch1,
1009 const char *branch2)
1010 {
1011 /*
1012 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1013 print_index_entry("\tpath: ", entry);
1014 */
1015 int clean_merge = 1;
1016 unsigned o_mode = entry->stages[1].mode;
1017 unsigned a_mode = entry->stages[2].mode;
1018 unsigned b_mode = entry->stages[3].mode;
1019 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1020 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1021 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1022
1023 if (o_sha && (!a_sha || !b_sha)) {
1024 /* Case A: Deleted in one */
1025 if ((!a_sha && !b_sha) ||
1026 (sha_eq(a_sha, o_sha) && !b_sha) ||
1027 (!a_sha && sha_eq(b_sha, o_sha))) {
1028 /* Deleted in both or deleted in one and
1029 * unchanged in the other */
1030 if (a_sha)
1031 output(2, "Removed %s", path);
1032 /* do not touch working file if it did not exist */
1033 remove_file(1, path, !a_sha);
1034 } else {
1035 /* Deleted in one and changed in the other */
1036 clean_merge = 0;
1037 if (!a_sha) {
1038 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1039 "and modified in %s. Version %s of %s left in tree.",
1040 path, branch1,
1041 branch2, branch2, path);
1042 update_file(0, b_sha, b_mode, path);
1043 } else {
1044 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1045 "and modified in %s. Version %s of %s left in tree.",
1046 path, branch2,
1047 branch1, branch1, path);
1048 update_file(0, a_sha, a_mode, path);
1049 }
1050 }
1051
1052 } else if ((!o_sha && a_sha && !b_sha) ||
1053 (!o_sha && !a_sha && b_sha)) {
1054 /* Case B: Added in one. */
1055 const char *add_branch;
1056 const char *other_branch;
1057 unsigned mode;
1058 const unsigned char *sha;
1059 const char *conf;
1060
1061 if (a_sha) {
1062 add_branch = branch1;
1063 other_branch = branch2;
1064 mode = a_mode;
1065 sha = a_sha;
1066 conf = "file/directory";
1067 } else {
1068 add_branch = branch2;
1069 other_branch = branch1;
1070 mode = b_mode;
1071 sha = b_sha;
1072 conf = "directory/file";
1073 }
1074 if (path_list_has_path(&current_directory_set, path)) {
1075 const char *new_path = unique_path(path, add_branch);
1076 clean_merge = 0;
1077 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1078 "Added %s as %s",
1079 conf, path, other_branch, path, new_path);
1080 remove_file(0, path, 0);
1081 update_file(0, sha, mode, new_path);
1082 } else {
1083 output(2, "Added %s", path);
1084 update_file(1, sha, mode, path);
1085 }
1086 } else if (a_sha && b_sha) {
1087 /* Case C: Added in both (check for same permissions) and */
1088 /* case D: Modified in both, but differently. */
1089 const char *reason = "content";
1090 struct merge_file_info mfi;
1091 struct diff_filespec o, a, b;
1092
1093 if (!o_sha) {
1094 reason = "add/add";
1095 o_sha = (unsigned char *)null_sha1;
1096 }
1097 output(2, "Auto-merged %s", path);
1098 o.path = a.path = b.path = (char *)path;
1099 hashcpy(o.sha1, o_sha);
1100 o.mode = o_mode;
1101 hashcpy(a.sha1, a_sha);
1102 a.mode = a_mode;
1103 hashcpy(b.sha1, b_sha);
1104 b.mode = b_mode;
1105
1106 mfi = merge_file(&o, &a, &b,
1107 branch1, branch2);
1108
1109 clean_merge = mfi.clean;
1110 if (mfi.clean)
1111 update_file(1, mfi.sha, mfi.mode, path);
1112 else if (S_ISGITLINK(mfi.mode))
1113 output(1, "CONFLICT (submodule): Merge conflict in %s "
1114 "- needs %s", path, sha1_to_hex(b.sha1));
1115 else {
1116 output(1, "CONFLICT (%s): Merge conflict in %s",
1117 reason, path);
1118
1119 if (index_only)
1120 update_file(0, mfi.sha, mfi.mode, path);
1121 else
1122 update_file_flags(mfi.sha, mfi.mode, path,
1123 0 /* update_cache */, 1 /* update_working_directory */);
1124 }
1125 } else if (!o_sha && !a_sha && !b_sha) {
1126 /*
1127 * this entry was deleted altogether. a_mode == 0 means
1128 * we had that path and want to actively remove it.
1129 */
1130 remove_file(1, path, !a_mode);
1131 } else
1132 die("Fatal merge failure, shouldn't happen.");
1133
1134 return clean_merge;
1135 }
1136
1137 int merge_trees(struct tree *head,
1138 struct tree *merge,
1139 struct tree *common,
1140 const char *branch1,
1141 const char *branch2,
1142 struct tree **result)
1143 {
1144 int code, clean;
1145
1146 if (subtree_merge) {
1147 merge = shift_tree_object(head, merge);
1148 common = shift_tree_object(head, common);
1149 }
1150
1151 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1152 output(0, "Already uptodate!");
1153 *result = head;
1154 return 1;
1155 }
1156
1157 code = git_merge_trees(index_only, common, head, merge);
1158
1159 if (code != 0)
1160 die("merging of trees %s and %s failed",
1161 sha1_to_hex(head->object.sha1),
1162 sha1_to_hex(merge->object.sha1));
1163
1164 if (unmerged_cache()) {
1165 struct path_list *entries, *re_head, *re_merge;
1166 int i;
1167 path_list_clear(&current_file_set, 1);
1168 path_list_clear(&current_directory_set, 1);
1169 get_files_dirs(head);
1170 get_files_dirs(merge);
1171
1172 entries = get_unmerged();
1173 re_head = get_renames(head, common, head, merge, entries);
1174 re_merge = get_renames(merge, common, head, merge, entries);
1175 clean = process_renames(re_head, re_merge,
1176 branch1, branch2);
1177 for (i = 0; i < entries->nr; i++) {
1178 const char *path = entries->items[i].path;
1179 struct stage_data *e = entries->items[i].util;
1180 if (!e->processed
1181 && !process_entry(path, e, branch1, branch2))
1182 clean = 0;
1183 }
1184
1185 path_list_clear(re_merge, 0);
1186 path_list_clear(re_head, 0);
1187 path_list_clear(entries, 1);
1188
1189 }
1190 else
1191 clean = 1;
1192
1193 if (index_only)
1194 *result = write_tree_from_memory();
1195
1196 return clean;
1197 }
1198
1199 static struct commit_list *reverse_commit_list(struct commit_list *list)
1200 {
1201 struct commit_list *next = NULL, *current, *backup;
1202 for (current = list; current; current = backup) {
1203 backup = current->next;
1204 current->next = next;
1205 next = current;
1206 }
1207 return next;
1208 }
1209
1210 /*
1211 * Merge the commits h1 and h2, return the resulting virtual
1212 * commit object and a flag indicating the cleanness of the merge.
1213 */
1214 int merge_recursive(struct commit *h1,
1215 struct commit *h2,
1216 const char *branch1,
1217 const char *branch2,
1218 struct commit_list *ca,
1219 struct commit **result)
1220 {
1221 struct commit_list *iter;
1222 struct commit *merged_common_ancestors;
1223 struct tree *mrtree = mrtree;
1224 int clean;
1225
1226 if (show(4)) {
1227 output(4, "Merging:");
1228 output_commit_title(h1);
1229 output_commit_title(h2);
1230 }
1231
1232 if (!ca) {
1233 ca = get_merge_bases(h1, h2, 1);
1234 ca = reverse_commit_list(ca);
1235 }
1236
1237 if (show(5)) {
1238 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1239 for (iter = ca; iter; iter = iter->next)
1240 output_commit_title(iter->item);
1241 }
1242
1243 merged_common_ancestors = pop_commit(&ca);
1244 if (merged_common_ancestors == NULL) {
1245 /* if there is no common ancestor, make an empty tree */
1246 struct tree *tree = xcalloc(1, sizeof(struct tree));
1247
1248 tree->object.parsed = 1;
1249 tree->object.type = OBJ_TREE;
1250 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1251 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1252 }
1253
1254 for (iter = ca; iter; iter = iter->next) {
1255 call_depth++;
1256 /*
1257 * When the merge fails, the result contains files
1258 * with conflict markers. The cleanness flag is
1259 * ignored, it was never actually used, as result of
1260 * merge_trees has always overwritten it: the committed
1261 * "conflicts" were already resolved.
1262 */
1263 discard_cache();
1264 merge_recursive(merged_common_ancestors, iter->item,
1265 "Temporary merge branch 1",
1266 "Temporary merge branch 2",
1267 NULL,
1268 &merged_common_ancestors);
1269 call_depth--;
1270
1271 if (!merged_common_ancestors)
1272 die("merge returned no commit");
1273 }
1274
1275 discard_cache();
1276 if (!call_depth) {
1277 read_cache();
1278 index_only = 0;
1279 } else
1280 index_only = 1;
1281
1282 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1283 branch1, branch2, &mrtree);
1284
1285 if (index_only) {
1286 *result = make_virtual_commit(mrtree, "merged tree");
1287 commit_list_insert(h1, &(*result)->parents);
1288 commit_list_insert(h2, &(*result)->parents->next);
1289 }
1290 flush_output();
1291 return clean;
1292 }
1293
1294 static const char *better_branch_name(const char *branch)
1295 {
1296 static char githead_env[8 + 40 + 1];
1297 char *name;
1298
1299 if (strlen(branch) != 40)
1300 return branch;
1301 sprintf(githead_env, "GITHEAD_%s", branch);
1302 name = getenv(githead_env);
1303 return name ? name : branch;
1304 }
1305
1306 static struct commit *get_ref(const char *ref)
1307 {
1308 unsigned char sha1[20];
1309 struct object *object;
1310
1311 if (get_sha1(ref, sha1))
1312 die("Could not resolve ref '%s'", ref);
1313 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1314 if (!object)
1315 return NULL;
1316 if (object->type == OBJ_TREE)
1317 return make_virtual_commit((struct tree*)object,
1318 better_branch_name(ref));
1319 if (object->type != OBJ_COMMIT)
1320 return NULL;
1321 if (parse_commit((struct commit *)object))
1322 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1323 return (struct commit *)object;
1324 }
1325
1326 static int merge_config(const char *var, const char *value)
1327 {
1328 if (!strcasecmp(var, "merge.verbosity")) {
1329 verbosity = git_config_int(var, value);
1330 return 0;
1331 }
1332 if (!strcasecmp(var, "diff.renamelimit")) {
1333 rename_limit = git_config_int(var, value);
1334 return 0;
1335 }
1336 return git_default_config(var, value);
1337 }
1338
1339 int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
1340 {
1341 static const char *bases[20];
1342 static unsigned bases_count = 0;
1343 int i, clean;
1344 const char *branch1, *branch2;
1345 struct commit *result, *h1, *h2;
1346 struct commit_list *ca = NULL;
1347 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1348 int index_fd;
1349
1350 if (argv[0]) {
1351 int namelen = strlen(argv[0]);
1352 if (8 < namelen &&
1353 !strcmp(argv[0] + namelen - 8, "-subtree"))
1354 subtree_merge = 1;
1355 }
1356
1357 git_config(merge_config);
1358 if (getenv("GIT_MERGE_VERBOSITY"))
1359 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1360
1361 if (argc < 4)
1362 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1363
1364 for (i = 1; i < argc; ++i) {
1365 if (!strcmp(argv[i], "--"))
1366 break;
1367 if (bases_count < sizeof(bases)/sizeof(*bases))
1368 bases[bases_count++] = argv[i];
1369 }
1370 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1371 die("Not handling anything other than two heads merge.");
1372 if (verbosity >= 5)
1373 buffer_output = 0;
1374
1375 branch1 = argv[++i];
1376 branch2 = argv[++i];
1377
1378 h1 = get_ref(branch1);
1379 h2 = get_ref(branch2);
1380
1381 branch1 = better_branch_name(branch1);
1382 branch2 = better_branch_name(branch2);
1383
1384 if (show(3))
1385 printf("Merging %s with %s\n", branch1, branch2);
1386
1387 index_fd = hold_locked_index(lock, 1);
1388
1389 for (i = 0; i < bases_count; i++) {
1390 struct commit *ancestor = get_ref(bases[i]);
1391 ca = commit_list_insert(ancestor, &ca);
1392 }
1393 clean = merge_recursive(h1, h2, branch1, branch2, ca, &result);
1394
1395 if (active_cache_changed &&
1396 (write_cache(index_fd, active_cache, active_nr) ||
1397 commit_locked_index(lock)))
1398 die ("unable to write %s", get_index_file());
1399
1400 return clean ? 0: 1;
1401 }
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