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hg-to-git: rewrite "git-frotz" to "git frotz"
[git/dscho.git] / builtin-merge-recursive.c
blob43bf6aa45eeacbb67490c809070f40023ce4e434
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 diff_rename_limit = -1;
96 static int merge_rename_limit = -1;
97 static int buffer_output = 1;
98 static struct strbuf obuf = STRBUF_INIT;
99
100 static int show(int v)
101 {
102 return (!call_depth && verbosity >= v) || verbosity >= 5;
103 }
104
105 static void flush_output(void)
106 {
107 if (obuf.len) {
108 fputs(obuf.buf, stdout);
109 strbuf_reset(&obuf);
110 }
111 }
112
113 static void output(int v, const char *fmt, ...)
114 {
115 int len;
116 va_list ap;
117
118 if (!show(v))
119 return;
120
121 strbuf_grow(&obuf, call_depth * 2 + 2);
122 memset(obuf.buf + obuf.len, ' ', call_depth * 2);
123 strbuf_setlen(&obuf, obuf.len + call_depth * 2);
124
125 va_start(ap, fmt);
126 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
127 va_end(ap);
128
129 if (len < 0)
130 len = 0;
131 if (len >= strbuf_avail(&obuf)) {
132 strbuf_grow(&obuf, len + 2);
133 va_start(ap, fmt);
134 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
135 va_end(ap);
136 if (len >= strbuf_avail(&obuf)) {
137 die("this should not happen, your snprintf is broken");
138 }
139 }
140 strbuf_setlen(&obuf, obuf.len + len);
141 strbuf_add(&obuf, "\n", 1);
142 if (!buffer_output)
143 flush_output();
144 }
145
146 static void output_commit_title(struct commit *commit)
147 {
148 int i;
149 flush_output();
150 for (i = call_depth; i--;)
151 fputs(" ", stdout);
152 if (commit->util)
153 printf("virtual %s\n", (char *)commit->util);
154 else {
155 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
156 if (parse_commit(commit) != 0)
157 printf("(bad commit)\n");
158 else {
159 const char *s;
160 int len;
161 for (s = commit->buffer; *s; s++)
162 if (*s == '\n' && s[1] == '\n') {
163 s += 2;
164 break;
165 }
166 for (len = 0; s[len] && '\n' != s[len]; len++)
167 ; /* do nothing */
168 printf("%.*s\n", len, s);
169 }
170 }
171 }
172
173 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
174 const char *path, int stage, int refresh, int options)
175 {
176 struct cache_entry *ce;
177 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
178 if (!ce)
179 return error("addinfo_cache failed for path '%s'", path);
180 return add_cache_entry(ce, options);
181 }
182
183 /*
184 * This is a global variable which is used in a number of places but
185 * only written to in the 'merge' function.
186 *
187 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
188 * don't update the working directory.
189 * 0 => Leave unmerged entries in the cache and update
190 * the working directory.
191 */
192 static int index_only = 0;
193
194 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
195 {
196 parse_tree(tree);
197 init_tree_desc(desc, tree->buffer, tree->size);
198 }
199
200 static int git_merge_trees(int index_only,
201 struct tree *common,
202 struct tree *head,
203 struct tree *merge)
204 {
205 int rc;
206 struct tree_desc t[3];
207 struct unpack_trees_options opts;
208
209 memset(&opts, 0, sizeof(opts));
210 if (index_only)
211 opts.index_only = 1;
212 else
213 opts.update = 1;
214 opts.merge = 1;
215 opts.head_idx = 2;
216 opts.fn = threeway_merge;
217 opts.src_index = &the_index;
218 opts.dst_index = &the_index;
219
220 init_tree_desc_from_tree(t+0, common);
221 init_tree_desc_from_tree(t+1, head);
222 init_tree_desc_from_tree(t+2, merge);
223
224 rc = unpack_trees(3, t, &opts);
225 cache_tree_free(&active_cache_tree);
226 return rc;
227 }
228
229 struct tree *write_tree_from_memory(void)
230 {
231 struct tree *result = NULL;
232
233 if (unmerged_cache()) {
234 int i;
235 output(0, "There are unmerged index entries:");
236 for (i = 0; i < active_nr; i++) {
237 struct cache_entry *ce = active_cache[i];
238 if (ce_stage(ce))
239 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
240 }
241 return NULL;
242 }
243
244 if (!active_cache_tree)
245 active_cache_tree = cache_tree();
246
247 if (!cache_tree_fully_valid(active_cache_tree) &&
248 cache_tree_update(active_cache_tree,
249 active_cache, active_nr, 0, 0) < 0)
250 die("error building trees");
251
252 result = lookup_tree(active_cache_tree->sha1);
253
254 return result;
255 }
256
257 static int save_files_dirs(const unsigned char *sha1,
258 const char *base, int baselen, const char *path,
259 unsigned int mode, int stage)
260 {
261 int len = strlen(path);
262 char *newpath = xmalloc(baselen + len + 1);
263 memcpy(newpath, base, baselen);
264 memcpy(newpath + baselen, path, len);
265 newpath[baselen + len] = '\0';
266
267 if (S_ISDIR(mode))
268 path_list_insert(newpath, &current_directory_set);
269 else
270 path_list_insert(newpath, &current_file_set);
271 free(newpath);
272
273 return READ_TREE_RECURSIVE;
274 }
275
276 static int get_files_dirs(struct tree *tree)
277 {
278 int n;
279 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
280 return 0;
281 n = current_file_set.nr + current_directory_set.nr;
282 return n;
283 }
284
285 /*
286 * Returns an index_entry instance which doesn't have to correspond to
287 * a real cache entry in Git's index.
288 */
289 static struct stage_data *insert_stage_data(const char *path,
290 struct tree *o, struct tree *a, struct tree *b,
291 struct path_list *entries)
292 {
293 struct path_list_item *item;
294 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
295 get_tree_entry(o->object.sha1, path,
296 e->stages[1].sha, &e->stages[1].mode);
297 get_tree_entry(a->object.sha1, path,
298 e->stages[2].sha, &e->stages[2].mode);
299 get_tree_entry(b->object.sha1, path,
300 e->stages[3].sha, &e->stages[3].mode);
301 item = path_list_insert(path, entries);
302 item->util = e;
303 return e;
304 }
305
306 /*
307 * Create a dictionary mapping file names to stage_data objects. The
308 * dictionary contains one entry for every path with a non-zero stage entry.
309 */
310 static struct path_list *get_unmerged(void)
311 {
312 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
313 int i;
314
315 unmerged->strdup_paths = 1;
316
317 for (i = 0; i < active_nr; i++) {
318 struct path_list_item *item;
319 struct stage_data *e;
320 struct cache_entry *ce = active_cache[i];
321 if (!ce_stage(ce))
322 continue;
323
324 item = path_list_lookup(ce->name, unmerged);
325 if (!item) {
326 item = path_list_insert(ce->name, unmerged);
327 item->util = xcalloc(1, sizeof(struct stage_data));
328 }
329 e = item->util;
330 e->stages[ce_stage(ce)].mode = ce->ce_mode;
331 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
332 }
333
334 return unmerged;
335 }
336
337 struct rename
338 {
339 struct diff_filepair *pair;
340 struct stage_data *src_entry;
341 struct stage_data *dst_entry;
342 unsigned processed:1;
343 };
344
345 /*
346 * Get information of all renames which occurred between 'o_tree' and
347 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
348 * 'b_tree') to be able to associate the correct cache entries with
349 * the rename information. 'tree' is always equal to either a_tree or b_tree.
350 */
351 static struct path_list *get_renames(struct tree *tree,
352 struct tree *o_tree,
353 struct tree *a_tree,
354 struct tree *b_tree,
355 struct path_list *entries)
356 {
357 int i;
358 struct path_list *renames;
359 struct diff_options opts;
360
361 renames = xcalloc(1, sizeof(struct path_list));
362 diff_setup(&opts);
363 DIFF_OPT_SET(&opts, RECURSIVE);
364 opts.detect_rename = DIFF_DETECT_RENAME;
365 opts.rename_limit = merge_rename_limit >= 0 ? merge_rename_limit :
366 diff_rename_limit >= 0 ? diff_rename_limit :
367 500;
368 opts.warn_on_too_large_rename = 1;
369 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
370 if (diff_setup_done(&opts) < 0)
371 die("diff setup failed");
372 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
373 diffcore_std(&opts);
374 for (i = 0; i < diff_queued_diff.nr; ++i) {
375 struct path_list_item *item;
376 struct rename *re;
377 struct diff_filepair *pair = diff_queued_diff.queue[i];
378 if (pair->status != 'R') {
379 diff_free_filepair(pair);
380 continue;
381 }
382 re = xmalloc(sizeof(*re));
383 re->processed = 0;
384 re->pair = pair;
385 item = path_list_lookup(re->pair->one->path, entries);
386 if (!item)
387 re->src_entry = insert_stage_data(re->pair->one->path,
388 o_tree, a_tree, b_tree, entries);
389 else
390 re->src_entry = item->util;
391
392 item = path_list_lookup(re->pair->two->path, entries);
393 if (!item)
394 re->dst_entry = insert_stage_data(re->pair->two->path,
395 o_tree, a_tree, b_tree, entries);
396 else
397 re->dst_entry = item->util;
398 item = path_list_insert(pair->one->path, renames);
399 item->util = re;
400 }
401 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
402 diff_queued_diff.nr = 0;
403 diff_flush(&opts);
404 return renames;
405 }
406
407 static int update_stages(const char *path, struct diff_filespec *o,
408 struct diff_filespec *a, struct diff_filespec *b,
409 int clear)
410 {
411 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
412 if (clear)
413 if (remove_file_from_cache(path))
414 return -1;
415 if (o)
416 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
417 return -1;
418 if (a)
419 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
420 return -1;
421 if (b)
422 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
423 return -1;
424 return 0;
425 }
426
427 static int remove_path(const char *name)
428 {
429 int ret;
430 char *slash, *dirs;
431
432 ret = unlink(name);
433 if (ret)
434 return ret;
435 dirs = xstrdup(name);
436 while ((slash = strrchr(name, '/'))) {
437 *slash = '\0';
438 if (rmdir(name) != 0)
439 break;
440 }
441 free(dirs);
442 return ret;
443 }
444
445 static int remove_file(int clean, const char *path, int no_wd)
446 {
447 int update_cache = index_only || clean;
448 int update_working_directory = !index_only && !no_wd;
449
450 if (update_cache) {
451 if (remove_file_from_cache(path))
452 return -1;
453 }
454 if (update_working_directory) {
455 unlink(path);
456 if (errno != ENOENT || errno != EISDIR)
457 return -1;
458 remove_path(path);
459 }
460 return 0;
461 }
462
463 static char *unique_path(const char *path, const char *branch)
464 {
465 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
466 int suffix = 0;
467 struct stat st;
468 char *p = newpath + strlen(path);
469 strcpy(newpath, path);
470 *(p++) = '~';
471 strcpy(p, branch);
472 for (; *p; ++p)
473 if ('/' == *p)
474 *p = '_';
475 while (path_list_has_path(&current_file_set, newpath) ||
476 path_list_has_path(&current_directory_set, newpath) ||
477 lstat(newpath, &st) == 0)
478 sprintf(p, "_%d", suffix++);
479
480 path_list_insert(newpath, &current_file_set);
481 return newpath;
482 }
483
484 static void flush_buffer(int fd, const char *buf, unsigned long size)
485 {
486 while (size > 0) {
487 long ret = write_in_full(fd, buf, size);
488 if (ret < 0) {
489 /* Ignore epipe */
490 if (errno == EPIPE)
491 break;
492 die("merge-recursive: %s", strerror(errno));
493 } else if (!ret) {
494 die("merge-recursive: disk full?");
495 }
496 size -= ret;
497 buf += ret;
498 }
499 }
500
501 static int make_room_for_path(const char *path)
502 {
503 int status;
504 const char *msg = "failed to create path '%s'%s";
505
506 status = safe_create_leading_directories_const(path);
507 if (status) {
508 if (status == -3) {
509 /* something else exists */
510 error(msg, path, ": perhaps a D/F conflict?");
511 return -1;
512 }
513 die(msg, path, "");
514 }
515
516 /* Successful unlink is good.. */
517 if (!unlink(path))
518 return 0;
519 /* .. and so is no existing file */
520 if (errno == ENOENT)
521 return 0;
522 /* .. but not some other error (who really cares what?) */
523 return error(msg, path, ": perhaps a D/F conflict?");
524 }
525
526 static void update_file_flags(const unsigned char *sha,
527 unsigned mode,
528 const char *path,
529 int update_cache,
530 int update_wd)
531 {
532 if (index_only)
533 update_wd = 0;
534
535 if (update_wd) {
536 enum object_type type;
537 void *buf;
538 unsigned long size;
539
540 if (S_ISGITLINK(mode))
541 die("cannot read object %s '%s': It is a submodule!",
542 sha1_to_hex(sha), path);
543
544 buf = read_sha1_file(sha, &type, &size);
545 if (!buf)
546 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
547 if (type != OBJ_BLOB)
548 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
549 if (S_ISREG(mode)) {
550 struct strbuf strbuf;
551 strbuf_init(&strbuf, 0);
552 if (convert_to_working_tree(path, buf, size, &strbuf)) {
553 free(buf);
554 size = strbuf.len;
555 buf = strbuf_detach(&strbuf, NULL);
556 }
557 }
558
559 if (make_room_for_path(path) < 0) {
560 update_wd = 0;
561 free(buf);
562 goto update_index;
563 }
564 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
565 int fd;
566 if (mode & 0100)
567 mode = 0777;
568 else
569 mode = 0666;
570 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
571 if (fd < 0)
572 die("failed to open %s: %s", path, strerror(errno));
573 flush_buffer(fd, buf, size);
574 close(fd);
575 } else if (S_ISLNK(mode)) {
576 char *lnk = xmemdupz(buf, size);
577 safe_create_leading_directories_const(path);
578 unlink(path);
579 symlink(lnk, path);
580 free(lnk);
581 } else
582 die("do not know what to do with %06o %s '%s'",
583 mode, sha1_to_hex(sha), path);
584 free(buf);
585 }
586 update_index:
587 if (update_cache)
588 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
589 }
590
591 static void update_file(int clean,
592 const unsigned char *sha,
593 unsigned mode,
594 const char *path)
595 {
596 update_file_flags(sha, mode, path, index_only || clean, !index_only);
597 }
598
599 /* Low level file merging, update and removal */
600
601 struct merge_file_info
602 {
603 unsigned char sha[20];
604 unsigned mode;
605 unsigned clean:1,
606 merge:1;
607 };
608
609 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
610 {
611 unsigned long size;
612 enum object_type type;
613
614 if (!hashcmp(sha1, null_sha1)) {
615 mm->ptr = xstrdup("");
616 mm->size = 0;
617 return;
618 }
619
620 mm->ptr = read_sha1_file(sha1, &type, &size);
621 if (!mm->ptr || type != OBJ_BLOB)
622 die("unable to read blob object %s", sha1_to_hex(sha1));
623 mm->size = size;
624 }
625
626 static int merge_3way(mmbuffer_t *result_buf,
627 struct diff_filespec *o,
628 struct diff_filespec *a,
629 struct diff_filespec *b,
630 const char *branch1,
631 const char *branch2)
632 {
633 mmfile_t orig, src1, src2;
634 char *name1, *name2;
635 int merge_status;
636
637 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
638 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
639
640 fill_mm(o->sha1, &orig);
641 fill_mm(a->sha1, &src1);
642 fill_mm(b->sha1, &src2);
643
644 merge_status = ll_merge(result_buf, a->path, &orig,
645 &src1, name1, &src2, name2,
646 index_only);
647
648 free(name1);
649 free(name2);
650 free(orig.ptr);
651 free(src1.ptr);
652 free(src2.ptr);
653 return merge_status;
654 }
655
656 static struct merge_file_info merge_file(struct diff_filespec *o,
657 struct diff_filespec *a, struct diff_filespec *b,
658 const char *branch1, const char *branch2)
659 {
660 struct merge_file_info result;
661 result.merge = 0;
662 result.clean = 1;
663
664 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
665 result.clean = 0;
666 if (S_ISREG(a->mode)) {
667 result.mode = a->mode;
668 hashcpy(result.sha, a->sha1);
669 } else {
670 result.mode = b->mode;
671 hashcpy(result.sha, b->sha1);
672 }
673 } else {
674 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
675 result.merge = 1;
676
677 /*
678 * Merge modes
679 */
680 if (a->mode == b->mode || a->mode == o->mode)
681 result.mode = b->mode;
682 else {
683 result.mode = a->mode;
684 if (b->mode != o->mode) {
685 result.clean = 0;
686 result.merge = 1;
687 }
688 }
689
690 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, o->sha1))
691 hashcpy(result.sha, b->sha1);
692 else if (sha_eq(b->sha1, o->sha1))
693 hashcpy(result.sha, a->sha1);
694 else if (S_ISREG(a->mode)) {
695 mmbuffer_t result_buf;
696 int merge_status;
697
698 merge_status = merge_3way(&result_buf, o, a, b,
699 branch1, branch2);
700
701 if ((merge_status < 0) || !result_buf.ptr)
702 die("Failed to execute internal merge");
703
704 if (write_sha1_file(result_buf.ptr, result_buf.size,
705 blob_type, result.sha))
706 die("Unable to add %s to database",
707 a->path);
708
709 free(result_buf.ptr);
710 result.clean = (merge_status == 0);
711 } else if (S_ISGITLINK(a->mode)) {
712 result.clean = 0;
713 hashcpy(result.sha, a->sha1);
714 } else if (S_ISLNK(a->mode)) {
715 hashcpy(result.sha, a->sha1);
716
717 if (!sha_eq(a->sha1, b->sha1))
718 result.clean = 0;
719 } else {
720 die("unsupported object type in the tree");
721 }
722 }
723
724 return result;
725 }
726
727 static void conflict_rename_rename(struct rename *ren1,
728 const char *branch1,
729 struct rename *ren2,
730 const char *branch2)
731 {
732 char *del[2];
733 int delp = 0;
734 const char *ren1_dst = ren1->pair->two->path;
735 const char *ren2_dst = ren2->pair->two->path;
736 const char *dst_name1 = ren1_dst;
737 const char *dst_name2 = ren2_dst;
738 if (path_list_has_path(&current_directory_set, ren1_dst)) {
739 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
740 output(1, "%s is a directory in %s added as %s instead",
741 ren1_dst, branch2, dst_name1);
742 remove_file(0, ren1_dst, 0);
743 }
744 if (path_list_has_path(&current_directory_set, ren2_dst)) {
745 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
746 output(1, "%s is a directory in %s added as %s instead",
747 ren2_dst, branch1, dst_name2);
748 remove_file(0, ren2_dst, 0);
749 }
750 if (index_only) {
751 remove_file_from_cache(dst_name1);
752 remove_file_from_cache(dst_name2);
753 /*
754 * Uncomment to leave the conflicting names in the resulting tree
755 *
756 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
757 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
758 */
759 } else {
760 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
761 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
762 }
763 while (delp--)
764 free(del[delp]);
765 }
766
767 static void conflict_rename_dir(struct rename *ren1,
768 const char *branch1)
769 {
770 char *new_path = unique_path(ren1->pair->two->path, branch1);
771 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
772 remove_file(0, ren1->pair->two->path, 0);
773 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
774 free(new_path);
775 }
776
777 static void conflict_rename_rename_2(struct rename *ren1,
778 const char *branch1,
779 struct rename *ren2,
780 const char *branch2)
781 {
782 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
783 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
784 output(1, "Renamed %s to %s and %s to %s instead",
785 ren1->pair->one->path, new_path1,
786 ren2->pair->one->path, new_path2);
787 remove_file(0, ren1->pair->two->path, 0);
788 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
789 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
790 free(new_path2);
791 free(new_path1);
792 }
793
794 static int process_renames(struct path_list *a_renames,
795 struct path_list *b_renames,
796 const char *a_branch,
797 const char *b_branch)
798 {
799 int clean_merge = 1, i, j;
800 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
801 const struct rename *sre;
802
803 for (i = 0; i < a_renames->nr; i++) {
804 sre = a_renames->items[i].util;
805 path_list_insert(sre->pair->two->path, &a_by_dst)->util
806 = sre->dst_entry;
807 }
808 for (i = 0; i < b_renames->nr; i++) {
809 sre = b_renames->items[i].util;
810 path_list_insert(sre->pair->two->path, &b_by_dst)->util
811 = sre->dst_entry;
812 }
813
814 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
815 int compare;
816 char *src;
817 struct path_list *renames1, *renames2, *renames2Dst;
818 struct rename *ren1 = NULL, *ren2 = NULL;
819 const char *branch1, *branch2;
820 const char *ren1_src, *ren1_dst;
821
822 if (i >= a_renames->nr) {
823 compare = 1;
824 ren2 = b_renames->items[j++].util;
825 } else if (j >= b_renames->nr) {
826 compare = -1;
827 ren1 = a_renames->items[i++].util;
828 } else {
829 compare = strcmp(a_renames->items[i].path,
830 b_renames->items[j].path);
831 if (compare <= 0)
832 ren1 = a_renames->items[i++].util;
833 if (compare >= 0)
834 ren2 = b_renames->items[j++].util;
835 }
836
837 /* TODO: refactor, so that 1/2 are not needed */
838 if (ren1) {
839 renames1 = a_renames;
840 renames2 = b_renames;
841 renames2Dst = &b_by_dst;
842 branch1 = a_branch;
843 branch2 = b_branch;
844 } else {
845 struct rename *tmp;
846 renames1 = b_renames;
847 renames2 = a_renames;
848 renames2Dst = &a_by_dst;
849 branch1 = b_branch;
850 branch2 = a_branch;
851 tmp = ren2;
852 ren2 = ren1;
853 ren1 = tmp;
854 }
855 src = ren1->pair->one->path;
856
857 ren1->dst_entry->processed = 1;
858 ren1->src_entry->processed = 1;
859
860 if (ren1->processed)
861 continue;
862 ren1->processed = 1;
863
864 ren1_src = ren1->pair->one->path;
865 ren1_dst = ren1->pair->two->path;
866
867 if (ren2) {
868 const char *ren2_src = ren2->pair->one->path;
869 const char *ren2_dst = ren2->pair->two->path;
870 /* Renamed in 1 and renamed in 2 */
871 if (strcmp(ren1_src, ren2_src) != 0)
872 die("ren1.src != ren2.src");
873 ren2->dst_entry->processed = 1;
874 ren2->processed = 1;
875 if (strcmp(ren1_dst, ren2_dst) != 0) {
876 clean_merge = 0;
877 output(1, "CONFLICT (rename/rename): "
878 "Rename \"%s\"->\"%s\" in branch \"%s\" "
879 "rename \"%s\"->\"%s\" in \"%s\"%s",
880 src, ren1_dst, branch1,
881 src, ren2_dst, branch2,
882 index_only ? " (left unresolved)": "");
883 if (index_only) {
884 remove_file_from_cache(src);
885 update_file(0, ren1->pair->one->sha1,
886 ren1->pair->one->mode, src);
887 }
888 conflict_rename_rename(ren1, branch1, ren2, branch2);
889 } else {
890 struct merge_file_info mfi;
891 remove_file(1, ren1_src, 1);
892 mfi = merge_file(ren1->pair->one,
893 ren1->pair->two,
894 ren2->pair->two,
895 branch1,
896 branch2);
897 if (mfi.merge || !mfi.clean)
898 output(1, "Renamed %s->%s", src, ren1_dst);
899
900 if (mfi.merge)
901 output(2, "Auto-merged %s", ren1_dst);
902
903 if (!mfi.clean) {
904 output(1, "CONFLICT (content): merge conflict in %s",
905 ren1_dst);
906 clean_merge = 0;
907
908 if (!index_only)
909 update_stages(ren1_dst,
910 ren1->pair->one,
911 ren1->pair->two,
912 ren2->pair->two,
913 1 /* clear */);
914 }
915 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
916 }
917 } else {
918 /* Renamed in 1, maybe changed in 2 */
919 struct path_list_item *item;
920 /* we only use sha1 and mode of these */
921 struct diff_filespec src_other, dst_other;
922 int try_merge, stage = a_renames == renames1 ? 3: 2;
923
924 remove_file(1, ren1_src, index_only || stage == 3);
925
926 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
927 src_other.mode = ren1->src_entry->stages[stage].mode;
928 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
929 dst_other.mode = ren1->dst_entry->stages[stage].mode;
930
931 try_merge = 0;
932
933 if (path_list_has_path(&current_directory_set, ren1_dst)) {
934 clean_merge = 0;
935 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
936 " directory %s added in %s",
937 ren1_src, ren1_dst, branch1,
938 ren1_dst, branch2);
939 conflict_rename_dir(ren1, branch1);
940 } else if (sha_eq(src_other.sha1, null_sha1)) {
941 clean_merge = 0;
942 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
943 "and deleted in %s",
944 ren1_src, ren1_dst, branch1,
945 branch2);
946 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
947 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
948 const char *new_path;
949 clean_merge = 0;
950 try_merge = 1;
951 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
952 "%s added in %s",
953 ren1_src, ren1_dst, branch1,
954 ren1_dst, branch2);
955 new_path = unique_path(ren1_dst, branch2);
956 output(1, "Added as %s instead", new_path);
957 update_file(0, dst_other.sha1, dst_other.mode, new_path);
958 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
959 ren2 = item->util;
960 clean_merge = 0;
961 ren2->processed = 1;
962 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
963 "Renamed %s->%s in %s",
964 ren1_src, ren1_dst, branch1,
965 ren2->pair->one->path, ren2->pair->two->path, branch2);
966 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
967 } else
968 try_merge = 1;
969
970 if (try_merge) {
971 struct diff_filespec *o, *a, *b;
972 struct merge_file_info mfi;
973 src_other.path = (char *)ren1_src;
974
975 o = ren1->pair->one;
976 if (a_renames == renames1) {
977 a = ren1->pair->two;
978 b = &src_other;
979 } else {
980 b = ren1->pair->two;
981 a = &src_other;
982 }
983 mfi = merge_file(o, a, b,
984 a_branch, b_branch);
985
986 if (mfi.clean &&
987 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
988 mfi.mode == ren1->pair->two->mode)
989 /*
990 * This messaged is part of
991 * t6022 test. If you change
992 * it update the test too.
993 */
994 output(3, "Skipped %s (merged same as existing)", ren1_dst);
995 else {
996 if (mfi.merge || !mfi.clean)
997 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
998 if (mfi.merge)
999 output(2, "Auto-merged %s", ren1_dst);
1000 if (!mfi.clean) {
1001 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
1002 ren1_dst);
1003 clean_merge = 0;
1004
1005 if (!index_only)
1006 update_stages(ren1_dst,
1007 o, a, b, 1);
1008 }
1009 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1010 }
1011 }
1012 }
1013 }
1014 path_list_clear(&a_by_dst, 0);
1015 path_list_clear(&b_by_dst, 0);
1016
1017 return clean_merge;
1018 }
1019
1020 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1021 {
1022 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1023 }
1024
1025 /* Per entry merge function */
1026 static int process_entry(const char *path, struct stage_data *entry,
1027 const char *branch1,
1028 const char *branch2)
1029 {
1030 /*
1031 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1032 print_index_entry("\tpath: ", entry);
1033 */
1034 int clean_merge = 1;
1035 unsigned o_mode = entry->stages[1].mode;
1036 unsigned a_mode = entry->stages[2].mode;
1037 unsigned b_mode = entry->stages[3].mode;
1038 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1039 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1040 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1041
1042 if (o_sha && (!a_sha || !b_sha)) {
1043 /* Case A: Deleted in one */
1044 if ((!a_sha && !b_sha) ||
1045 (sha_eq(a_sha, o_sha) && !b_sha) ||
1046 (!a_sha && sha_eq(b_sha, o_sha))) {
1047 /* Deleted in both or deleted in one and
1048 * unchanged in the other */
1049 if (a_sha)
1050 output(2, "Removed %s", path);
1051 /* do not touch working file if it did not exist */
1052 remove_file(1, path, !a_sha);
1053 } else {
1054 /* Deleted in one and changed in the other */
1055 clean_merge = 0;
1056 if (!a_sha) {
1057 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1058 "and modified in %s. Version %s of %s left in tree.",
1059 path, branch1,
1060 branch2, branch2, path);
1061 update_file(0, b_sha, b_mode, path);
1062 } else {
1063 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1064 "and modified in %s. Version %s of %s left in tree.",
1065 path, branch2,
1066 branch1, branch1, path);
1067 update_file(0, a_sha, a_mode, path);
1068 }
1069 }
1070
1071 } else if ((!o_sha && a_sha && !b_sha) ||
1072 (!o_sha && !a_sha && b_sha)) {
1073 /* Case B: Added in one. */
1074 const char *add_branch;
1075 const char *other_branch;
1076 unsigned mode;
1077 const unsigned char *sha;
1078 const char *conf;
1079
1080 if (a_sha) {
1081 add_branch = branch1;
1082 other_branch = branch2;
1083 mode = a_mode;
1084 sha = a_sha;
1085 conf = "file/directory";
1086 } else {
1087 add_branch = branch2;
1088 other_branch = branch1;
1089 mode = b_mode;
1090 sha = b_sha;
1091 conf = "directory/file";
1092 }
1093 if (path_list_has_path(&current_directory_set, path)) {
1094 const char *new_path = unique_path(path, add_branch);
1095 clean_merge = 0;
1096 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1097 "Added %s as %s",
1098 conf, path, other_branch, path, new_path);
1099 remove_file(0, path, 0);
1100 update_file(0, sha, mode, new_path);
1101 } else {
1102 output(2, "Added %s", path);
1103 update_file(1, sha, mode, path);
1104 }
1105 } else if (a_sha && b_sha) {
1106 /* Case C: Added in both (check for same permissions) and */
1107 /* case D: Modified in both, but differently. */
1108 const char *reason = "content";
1109 struct merge_file_info mfi;
1110 struct diff_filespec o, a, b;
1111
1112 if (!o_sha) {
1113 reason = "add/add";
1114 o_sha = (unsigned char *)null_sha1;
1115 }
1116 output(2, "Auto-merged %s", path);
1117 o.path = a.path = b.path = (char *)path;
1118 hashcpy(o.sha1, o_sha);
1119 o.mode = o_mode;
1120 hashcpy(a.sha1, a_sha);
1121 a.mode = a_mode;
1122 hashcpy(b.sha1, b_sha);
1123 b.mode = b_mode;
1124
1125 mfi = merge_file(&o, &a, &b,
1126 branch1, branch2);
1127
1128 clean_merge = mfi.clean;
1129 if (mfi.clean)
1130 update_file(1, mfi.sha, mfi.mode, path);
1131 else if (S_ISGITLINK(mfi.mode))
1132 output(1, "CONFLICT (submodule): Merge conflict in %s "
1133 "- needs %s", path, sha1_to_hex(b.sha1));
1134 else {
1135 output(1, "CONFLICT (%s): Merge conflict in %s",
1136 reason, path);
1137
1138 if (index_only)
1139 update_file(0, mfi.sha, mfi.mode, path);
1140 else
1141 update_file_flags(mfi.sha, mfi.mode, path,
1142 0 /* update_cache */, 1 /* update_working_directory */);
1143 }
1144 } else if (!o_sha && !a_sha && !b_sha) {
1145 /*
1146 * this entry was deleted altogether. a_mode == 0 means
1147 * we had that path and want to actively remove it.
1148 */
1149 remove_file(1, path, !a_mode);
1150 } else
1151 die("Fatal merge failure, shouldn't happen.");
1152
1153 return clean_merge;
1154 }
1155
1156 int merge_trees(struct tree *head,
1157 struct tree *merge,
1158 struct tree *common,
1159 const char *branch1,
1160 const char *branch2,
1161 struct tree **result)
1162 {
1163 int code, clean;
1164
1165 if (subtree_merge) {
1166 merge = shift_tree_object(head, merge);
1167 common = shift_tree_object(head, common);
1168 }
1169
1170 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1171 output(0, "Already uptodate!");
1172 *result = head;
1173 return 1;
1174 }
1175
1176 code = git_merge_trees(index_only, common, head, merge);
1177
1178 if (code != 0)
1179 die("merging of trees %s and %s failed",
1180 sha1_to_hex(head->object.sha1),
1181 sha1_to_hex(merge->object.sha1));
1182
1183 if (unmerged_cache()) {
1184 struct path_list *entries, *re_head, *re_merge;
1185 int i;
1186 path_list_clear(&current_file_set, 1);
1187 path_list_clear(&current_directory_set, 1);
1188 get_files_dirs(head);
1189 get_files_dirs(merge);
1190
1191 entries = get_unmerged();
1192 re_head = get_renames(head, common, head, merge, entries);
1193 re_merge = get_renames(merge, common, head, merge, entries);
1194 clean = process_renames(re_head, re_merge,
1195 branch1, branch2);
1196 for (i = 0; i < entries->nr; i++) {
1197 const char *path = entries->items[i].path;
1198 struct stage_data *e = entries->items[i].util;
1199 if (!e->processed
1200 && !process_entry(path, e, branch1, branch2))
1201 clean = 0;
1202 }
1203
1204 path_list_clear(re_merge, 0);
1205 path_list_clear(re_head, 0);
1206 path_list_clear(entries, 1);
1207
1208 }
1209 else
1210 clean = 1;
1211
1212 if (index_only)
1213 *result = write_tree_from_memory();
1214
1215 return clean;
1216 }
1217
1218 static struct commit_list *reverse_commit_list(struct commit_list *list)
1219 {
1220 struct commit_list *next = NULL, *current, *backup;
1221 for (current = list; current; current = backup) {
1222 backup = current->next;
1223 current->next = next;
1224 next = current;
1225 }
1226 return next;
1227 }
1228
1229 /*
1230 * Merge the commits h1 and h2, return the resulting virtual
1231 * commit object and a flag indicating the cleanness of the merge.
1232 */
1233 int merge_recursive(struct commit *h1,
1234 struct commit *h2,
1235 const char *branch1,
1236 const char *branch2,
1237 struct commit_list *ca,
1238 struct commit **result)
1239 {
1240 struct commit_list *iter;
1241 struct commit *merged_common_ancestors;
1242 struct tree *mrtree = mrtree;
1243 int clean;
1244
1245 if (show(4)) {
1246 output(4, "Merging:");
1247 output_commit_title(h1);
1248 output_commit_title(h2);
1249 }
1250
1251 if (!ca) {
1252 ca = get_merge_bases(h1, h2, 1);
1253 ca = reverse_commit_list(ca);
1254 }
1255
1256 if (show(5)) {
1257 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1258 for (iter = ca; iter; iter = iter->next)
1259 output_commit_title(iter->item);
1260 }
1261
1262 merged_common_ancestors = pop_commit(&ca);
1263 if (merged_common_ancestors == NULL) {
1264 /* if there is no common ancestor, make an empty tree */
1265 struct tree *tree = xcalloc(1, sizeof(struct tree));
1266
1267 tree->object.parsed = 1;
1268 tree->object.type = OBJ_TREE;
1269 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1270 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1271 }
1272
1273 for (iter = ca; iter; iter = iter->next) {
1274 call_depth++;
1275 /*
1276 * When the merge fails, the result contains files
1277 * with conflict markers. The cleanness flag is
1278 * ignored, it was never actually used, as result of
1279 * merge_trees has always overwritten it: the committed
1280 * "conflicts" were already resolved.
1281 */
1282 discard_cache();
1283 merge_recursive(merged_common_ancestors, iter->item,
1284 "Temporary merge branch 1",
1285 "Temporary merge branch 2",
1286 NULL,
1287 &merged_common_ancestors);
1288 call_depth--;
1289
1290 if (!merged_common_ancestors)
1291 die("merge returned no commit");
1292 }
1293
1294 discard_cache();
1295 if (!call_depth) {
1296 read_cache();
1297 index_only = 0;
1298 } else
1299 index_only = 1;
1300
1301 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1302 branch1, branch2, &mrtree);
1303
1304 if (index_only) {
1305 *result = make_virtual_commit(mrtree, "merged tree");
1306 commit_list_insert(h1, &(*result)->parents);
1307 commit_list_insert(h2, &(*result)->parents->next);
1308 }
1309 flush_output();
1310 return clean;
1311 }
1312
1313 static const char *better_branch_name(const char *branch)
1314 {
1315 static char githead_env[8 + 40 + 1];
1316 char *name;
1317
1318 if (strlen(branch) != 40)
1319 return branch;
1320 sprintf(githead_env, "GITHEAD_%s", branch);
1321 name = getenv(githead_env);
1322 return name ? name : branch;
1323 }
1324
1325 static struct commit *get_ref(const char *ref)
1326 {
1327 unsigned char sha1[20];
1328 struct object *object;
1329
1330 if (get_sha1(ref, sha1))
1331 die("Could not resolve ref '%s'", ref);
1332 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1333 if (!object)
1334 return NULL;
1335 if (object->type == OBJ_TREE)
1336 return make_virtual_commit((struct tree*)object,
1337 better_branch_name(ref));
1338 if (object->type != OBJ_COMMIT)
1339 return NULL;
1340 if (parse_commit((struct commit *)object))
1341 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1342 return (struct commit *)object;
1343 }
1344
1345 static int merge_config(const char *var, const char *value, void *cb)
1346 {
1347 if (!strcasecmp(var, "merge.verbosity")) {
1348 verbosity = git_config_int(var, value);
1349 return 0;
1350 }
1351 if (!strcasecmp(var, "diff.renamelimit")) {
1352 diff_rename_limit = git_config_int(var, value);
1353 return 0;
1354 }
1355 if (!strcasecmp(var, "merge.renamelimit")) {
1356 merge_rename_limit = git_config_int(var, value);
1357 return 0;
1358 }
1359 return git_default_config(var, value, cb);
1360 }
1361
1362 int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
1363 {
1364 static const char *bases[20];
1365 static unsigned bases_count = 0;
1366 int i, clean;
1367 const char *branch1, *branch2;
1368 struct commit *result, *h1, *h2;
1369 struct commit_list *ca = NULL;
1370 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1371 int index_fd;
1372
1373 if (argv[0]) {
1374 int namelen = strlen(argv[0]);
1375 if (8 < namelen &&
1376 !strcmp(argv[0] + namelen - 8, "-subtree"))
1377 subtree_merge = 1;
1378 }
1379
1380 git_config(merge_config, NULL);
1381 if (getenv("GIT_MERGE_VERBOSITY"))
1382 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1383
1384 if (argc < 4)
1385 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1386
1387 for (i = 1; i < argc; ++i) {
1388 if (!strcmp(argv[i], "--"))
1389 break;
1390 if (bases_count < sizeof(bases)/sizeof(*bases))
1391 bases[bases_count++] = argv[i];
1392 }
1393 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1394 die("Not handling anything other than two heads merge.");
1395 if (verbosity >= 5)
1396 buffer_output = 0;
1397
1398 branch1 = argv[++i];
1399 branch2 = argv[++i];
1400
1401 h1 = get_ref(branch1);
1402 h2 = get_ref(branch2);
1403
1404 branch1 = better_branch_name(branch1);
1405 branch2 = better_branch_name(branch2);
1406
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_recursive(h1, h2, branch1, branch2, ca, &result);
1417
1418 if (active_cache_changed &&
1419 (write_cache(index_fd, active_cache, active_nr) ||
1420 commit_locked_index(lock)))
1421 die ("unable to write %s", get_index_file());
1422
1423 return clean ? 0: 1;
1424 }
Dscho's miscellaneous git branches