Enable output buffering in 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 struct output_buffer
71 {
72 struct output_buffer *next;
73 char *str;
74 };
75
76 static struct path_list current_file_set = {NULL, 0, 0, 1};
77 static struct path_list current_directory_set = {NULL, 0, 0, 1};
78
79 static int call_depth = 0;
80 static int verbosity = 2;
81 static int buffer_output = 1;
82 static struct output_buffer *output_list, *output_end;
83
84 static int show (int v)
85 {
86 return (!call_depth && verbosity >= v) || verbosity >= 5;
87 }
88
89 static void output(int v, const char *fmt, ...)
90 {
91 va_list args;
92 va_start(args, fmt);
93 if (buffer_output && show(v)) {
94 struct output_buffer *b = xmalloc(sizeof(*b));
95 nfvasprintf(&b->str, fmt, args);
96 b->next = NULL;
97 if (output_end)
98 output_end->next = b;
99 else
100 output_list = b;
101 output_end = b;
102 } else if (show(v)) {
103 int i;
104 for (i = call_depth; i--;)
105 fputs(" ", stdout);
106 vfprintf(stdout, fmt, args);
107 fputc('\n', stdout);
108 }
109 va_end(args);
110 }
111
112 static void flush_output()
113 {
114 struct output_buffer *b, *n;
115 for (b = output_list; b; b = n) {
116 int i;
117 for (i = call_depth; i--;)
118 fputs(" ", stdout);
119 fputs(b->str, stdout);
120 fputc('\n', stdout);
121 n = b->next;
122 free(b->str);
123 free(b);
124 }
125 output_list = NULL;
126 output_end = NULL;
127 }
128
129 static void output_commit_title(struct commit *commit)
130 {
131 int i;
132 flush_output();
133 for (i = call_depth; i--;)
134 fputs(" ", stdout);
135 if (commit->util)
136 printf("virtual %s\n", (char *)commit->util);
137 else {
138 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
139 if (parse_commit(commit) != 0)
140 printf("(bad commit)\n");
141 else {
142 const char *s;
143 int len;
144 for (s = commit->buffer; *s; s++)
145 if (*s == '\n' && s[1] == '\n') {
146 s += 2;
147 break;
148 }
149 for (len = 0; s[len] && '\n' != s[len]; len++)
150 ; /* do nothing */
151 printf("%.*s\n", len, s);
152 }
153 }
154 }
155
156 static struct cache_entry *make_cache_entry(unsigned int mode,
157 const unsigned char *sha1, const char *path, int stage, int refresh)
158 {
159 int size, len;
160 struct cache_entry *ce;
161
162 if (!verify_path(path))
163 return NULL;
164
165 len = strlen(path);
166 size = cache_entry_size(len);
167 ce = xcalloc(1, size);
168
169 hashcpy(ce->sha1, sha1);
170 memcpy(ce->name, path, len);
171 ce->ce_flags = create_ce_flags(len, stage);
172 ce->ce_mode = create_ce_mode(mode);
173
174 if (refresh)
175 return refresh_cache_entry(ce, 0);
176
177 return ce;
178 }
179
180 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
181 const char *path, int stage, int refresh, int options)
182 {
183 struct cache_entry *ce;
184 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
185 if (!ce)
186 return error("cache_addinfo failed: %s", strerror(cache_errno));
187 return add_cache_entry(ce, options);
188 }
189
190 /*
191 * This is a global variable which is used in a number of places but
192 * only written to in the 'merge' function.
193 *
194 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
195 * don't update the working directory.
196 * 0 => Leave unmerged entries in the cache and update
197 * the working directory.
198 */
199 static int index_only = 0;
200
201 static int git_merge_trees(int index_only,
202 struct tree *common,
203 struct tree *head,
204 struct tree *merge)
205 {
206 int rc;
207 struct object_list *trees = NULL;
208 struct unpack_trees_options opts;
209
210 memset(&opts, 0, sizeof(opts));
211 if (index_only)
212 opts.index_only = 1;
213 else
214 opts.update = 1;
215 opts.merge = 1;
216 opts.head_idx = 2;
217 opts.fn = threeway_merge;
218
219 object_list_append(&common->object, &trees);
220 object_list_append(&head->object, &trees);
221 object_list_append(&merge->object, &trees);
222
223 rc = unpack_trees(trees, &opts);
224 cache_tree_free(&active_cache_tree);
225 return rc;
226 }
227
228 static int unmerged_index(void)
229 {
230 int i;
231 for (i = 0; i < active_nr; i++) {
232 struct cache_entry *ce = active_cache[i];
233 if (ce_stage(ce))
234 return 1;
235 }
236 return 0;
237 }
238
239 static struct tree *git_write_tree(void)
240 {
241 struct tree *result = NULL;
242
243 if (unmerged_index())
244 return NULL;
245
246 if (!active_cache_tree)
247 active_cache_tree = cache_tree();
248
249 if (!cache_tree_fully_valid(active_cache_tree) &&
250 cache_tree_update(active_cache_tree,
251 active_cache, active_nr, 0, 0) < 0)
252 die("error building trees");
253
254 result = lookup_tree(active_cache_tree->sha1);
255
256 return result;
257 }
258
259 static int save_files_dirs(const unsigned char *sha1,
260 const char *base, int baselen, const char *path,
261 unsigned int mode, int stage)
262 {
263 int len = strlen(path);
264 char *newpath = xmalloc(baselen + len + 1);
265 memcpy(newpath, base, baselen);
266 memcpy(newpath + baselen, path, len);
267 newpath[baselen + len] = '\0';
268
269 if (S_ISDIR(mode))
270 path_list_insert(newpath, &current_directory_set);
271 else
272 path_list_insert(newpath, &current_file_set);
273 free(newpath);
274
275 return READ_TREE_RECURSIVE;
276 }
277
278 static int get_files_dirs(struct tree *tree)
279 {
280 int n;
281 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
282 return 0;
283 n = current_file_set.nr + current_directory_set.nr;
284 return n;
285 }
286
287 /*
288 * Returns a index_entry instance which doesn't have to correspond to
289 * a real cache entry in Git's index.
290 */
291 static struct stage_data *insert_stage_data(const char *path,
292 struct tree *o, struct tree *a, struct tree *b,
293 struct path_list *entries)
294 {
295 struct path_list_item *item;
296 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
297 get_tree_entry(o->object.sha1, path,
298 e->stages[1].sha, &e->stages[1].mode);
299 get_tree_entry(a->object.sha1, path,
300 e->stages[2].sha, &e->stages[2].mode);
301 get_tree_entry(b->object.sha1, path,
302 e->stages[3].sha, &e->stages[3].mode);
303 item = path_list_insert(path, entries);
304 item->util = e;
305 return e;
306 }
307
308 /*
309 * Create a dictionary mapping file names to stage_data objects. The
310 * dictionary contains one entry for every path with a non-zero stage entry.
311 */
312 static struct path_list *get_unmerged(void)
313 {
314 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
315 int i;
316
317 unmerged->strdup_paths = 1;
318
319 for (i = 0; i < active_nr; i++) {
320 struct path_list_item *item;
321 struct stage_data *e;
322 struct cache_entry *ce = active_cache[i];
323 if (!ce_stage(ce))
324 continue;
325
326 item = path_list_lookup(ce->name, unmerged);
327 if (!item) {
328 item = path_list_insert(ce->name, unmerged);
329 item->util = xcalloc(1, sizeof(struct stage_data));
330 }
331 e = item->util;
332 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
333 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
334 }
335
336 return unmerged;
337 }
338
339 struct rename
340 {
341 struct diff_filepair *pair;
342 struct stage_data *src_entry;
343 struct stage_data *dst_entry;
344 unsigned processed:1;
345 };
346
347 /*
348 * Get information of all renames which occured between 'o_tree' and
349 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
350 * 'b_tree') to be able to associate the correct cache entries with
351 * the rename information. 'tree' is always equal to either a_tree or b_tree.
352 */
353 static struct path_list *get_renames(struct tree *tree,
354 struct tree *o_tree,
355 struct tree *a_tree,
356 struct tree *b_tree,
357 struct path_list *entries)
358 {
359 int i;
360 struct path_list *renames;
361 struct diff_options opts;
362
363 renames = xcalloc(1, sizeof(struct path_list));
364 diff_setup(&opts);
365 opts.recursive = 1;
366 opts.detect_rename = DIFF_DETECT_RENAME;
367 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
368 if (diff_setup_done(&opts) < 0)
369 die("diff setup failed");
370 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
371 diffcore_std(&opts);
372 for (i = 0; i < diff_queued_diff.nr; ++i) {
373 struct path_list_item *item;
374 struct rename *re;
375 struct diff_filepair *pair = diff_queued_diff.queue[i];
376 if (pair->status != 'R') {
377 diff_free_filepair(pair);
378 continue;
379 }
380 re = xmalloc(sizeof(*re));
381 re->processed = 0;
382 re->pair = pair;
383 item = path_list_lookup(re->pair->one->path, entries);
384 if (!item)
385 re->src_entry = insert_stage_data(re->pair->one->path,
386 o_tree, a_tree, b_tree, entries);
387 else
388 re->src_entry = item->util;
389
390 item = path_list_lookup(re->pair->two->path, entries);
391 if (!item)
392 re->dst_entry = insert_stage_data(re->pair->two->path,
393 o_tree, a_tree, b_tree, entries);
394 else
395 re->dst_entry = item->util;
396 item = path_list_insert(pair->one->path, renames);
397 item->util = re;
398 }
399 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
400 diff_queued_diff.nr = 0;
401 diff_flush(&opts);
402 return renames;
403 }
404
405 static int update_stages(const char *path, struct diff_filespec *o,
406 struct diff_filespec *a, struct diff_filespec *b,
407 int clear)
408 {
409 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
410 if (clear)
411 if (remove_file_from_cache(path))
412 return -1;
413 if (o)
414 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
415 return -1;
416 if (a)
417 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
418 return -1;
419 if (b)
420 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
421 return -1;
422 return 0;
423 }
424
425 static int remove_path(const char *name)
426 {
427 int ret, len;
428 char *slash, *dirs;
429
430 ret = unlink(name);
431 if (ret)
432 return ret;
433 len = strlen(name);
434 dirs = xmalloc(len+1);
435 memcpy(dirs, name, len);
436 dirs[len] = '\0';
437 while ((slash = strrchr(name, '/'))) {
438 *slash = '\0';
439 len = slash - name;
440 if (rmdir(name) != 0)
441 break;
442 }
443 free(dirs);
444 return ret;
445 }
446
447 static int remove_file(int clean, const char *path, int no_wd)
448 {
449 int update_cache = index_only || clean;
450 int update_working_directory = !index_only && !no_wd;
451
452 if (update_cache) {
453 if (remove_file_from_cache(path))
454 return -1;
455 }
456 if (update_working_directory) {
457 unlink(path);
458 if (errno != ENOENT || errno != EISDIR)
459 return -1;
460 remove_path(path);
461 }
462 return 0;
463 }
464
465 static char *unique_path(const char *path, const char *branch)
466 {
467 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
468 int suffix = 0;
469 struct stat st;
470 char *p = newpath + strlen(path);
471 strcpy(newpath, path);
472 *(p++) = '~';
473 strcpy(p, branch);
474 for (; *p; ++p)
475 if ('/' == *p)
476 *p = '_';
477 while (path_list_has_path(&current_file_set, newpath) ||
478 path_list_has_path(&current_directory_set, newpath) ||
479 lstat(newpath, &st) == 0)
480 sprintf(p, "_%d", suffix++);
481
482 path_list_insert(newpath, &current_file_set);
483 return newpath;
484 }
485
486 static int mkdir_p(const char *path, unsigned long mode)
487 {
488 /* path points to cache entries, so xstrdup before messing with it */
489 char *buf = xstrdup(path);
490 int result = safe_create_leading_directories(buf);
491 free(buf);
492 return result;
493 }
494
495 static void flush_buffer(int fd, const char *buf, unsigned long size)
496 {
497 while (size > 0) {
498 long ret = write_in_full(fd, buf, size);
499 if (ret < 0) {
500 /* Ignore epipe */
501 if (errno == EPIPE)
502 break;
503 die("merge-recursive: %s", strerror(errno));
504 } else if (!ret) {
505 die("merge-recursive: disk full?");
506 }
507 size -= ret;
508 buf += ret;
509 }
510 }
511
512 static void update_file_flags(const unsigned char *sha,
513 unsigned mode,
514 const char *path,
515 int update_cache,
516 int update_wd)
517 {
518 if (index_only)
519 update_wd = 0;
520
521 if (update_wd) {
522 char type[20];
523 void *buf;
524 unsigned long size;
525
526 buf = read_sha1_file(sha, type, &size);
527 if (!buf)
528 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
529 if (strcmp(type, blob_type) != 0)
530 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
531
532 if (S_ISREG(mode)) {
533 int fd;
534 if (mkdir_p(path, 0777))
535 die("failed to create path %s: %s", path, strerror(errno));
536 unlink(path);
537 if (mode & 0100)
538 mode = 0777;
539 else
540 mode = 0666;
541 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
542 if (fd < 0)
543 die("failed to open %s: %s", path, strerror(errno));
544 flush_buffer(fd, buf, size);
545 close(fd);
546 } else if (S_ISLNK(mode)) {
547 char *lnk = xmalloc(size + 1);
548 memcpy(lnk, buf, size);
549 lnk[size] = '\0';
550 mkdir_p(path, 0777);
551 unlink(lnk);
552 symlink(lnk, path);
553 } else
554 die("do not know what to do with %06o %s '%s'",
555 mode, sha1_to_hex(sha), path);
556 }
557 if (update_cache)
558 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
559 }
560
561 static void update_file(int clean,
562 const unsigned char *sha,
563 unsigned mode,
564 const char *path)
565 {
566 update_file_flags(sha, mode, path, index_only || clean, !index_only);
567 }
568
569 /* Low level file merging, update and removal */
570
571 struct merge_file_info
572 {
573 unsigned char sha[20];
574 unsigned mode;
575 unsigned clean:1,
576 merge:1;
577 };
578
579 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
580 {
581 unsigned long size;
582 char type[20];
583
584 if (!hashcmp(sha1, null_sha1)) {
585 mm->ptr = xstrdup("");
586 mm->size = 0;
587 return;
588 }
589
590 mm->ptr = read_sha1_file(sha1, type, &size);
591 if (!mm->ptr || strcmp(type, blob_type))
592 die("unable to read blob object %s", sha1_to_hex(sha1));
593 mm->size = size;
594 }
595
596 static struct merge_file_info merge_file(struct diff_filespec *o,
597 struct diff_filespec *a, struct diff_filespec *b,
598 const char *branch1, const char *branch2)
599 {
600 struct merge_file_info result;
601 result.merge = 0;
602 result.clean = 1;
603
604 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
605 result.clean = 0;
606 if (S_ISREG(a->mode)) {
607 result.mode = a->mode;
608 hashcpy(result.sha, a->sha1);
609 } else {
610 result.mode = b->mode;
611 hashcpy(result.sha, b->sha1);
612 }
613 } else {
614 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
615 result.merge = 1;
616
617 result.mode = a->mode == o->mode ? b->mode: a->mode;
618
619 if (sha_eq(a->sha1, o->sha1))
620 hashcpy(result.sha, b->sha1);
621 else if (sha_eq(b->sha1, o->sha1))
622 hashcpy(result.sha, a->sha1);
623 else if (S_ISREG(a->mode)) {
624 mmfile_t orig, src1, src2;
625 mmbuffer_t result_buf;
626 xpparam_t xpp;
627 char *name1, *name2;
628 int merge_status;
629
630 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
631 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
632
633 fill_mm(o->sha1, &orig);
634 fill_mm(a->sha1, &src1);
635 fill_mm(b->sha1, &src2);
636
637 memset(&xpp, 0, sizeof(xpp));
638 merge_status = xdl_merge(&orig,
639 &src1, name1,
640 &src2, name2,
641 &xpp, XDL_MERGE_ZEALOUS,
642 &result_buf);
643 free(name1);
644 free(name2);
645 free(orig.ptr);
646 free(src1.ptr);
647 free(src2.ptr);
648
649 if ((merge_status < 0) || !result_buf.ptr)
650 die("Failed to execute internal merge");
651
652 if (write_sha1_file(result_buf.ptr, result_buf.size,
653 blob_type, result.sha))
654 die("Unable to add %s to database",
655 a->path);
656
657 free(result_buf.ptr);
658 result.clean = (merge_status == 0);
659 } else {
660 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
661 die("cannot merge modes?");
662
663 hashcpy(result.sha, a->sha1);
664
665 if (!sha_eq(a->sha1, b->sha1))
666 result.clean = 0;
667 }
668 }
669
670 return result;
671 }
672
673 static void conflict_rename_rename(struct rename *ren1,
674 const char *branch1,
675 struct rename *ren2,
676 const char *branch2)
677 {
678 char *del[2];
679 int delp = 0;
680 const char *ren1_dst = ren1->pair->two->path;
681 const char *ren2_dst = ren2->pair->two->path;
682 const char *dst_name1 = ren1_dst;
683 const char *dst_name2 = ren2_dst;
684 if (path_list_has_path(&current_directory_set, ren1_dst)) {
685 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
686 output(1, "%s is a directory in %s adding as %s instead",
687 ren1_dst, branch2, dst_name1);
688 remove_file(0, ren1_dst, 0);
689 }
690 if (path_list_has_path(&current_directory_set, ren2_dst)) {
691 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
692 output(1, "%s is a directory in %s adding as %s instead",
693 ren2_dst, branch1, dst_name2);
694 remove_file(0, ren2_dst, 0);
695 }
696 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
697 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
698 while (delp--)
699 free(del[delp]);
700 }
701
702 static void conflict_rename_dir(struct rename *ren1,
703 const char *branch1)
704 {
705 char *new_path = unique_path(ren1->pair->two->path, branch1);
706 output(1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
707 remove_file(0, ren1->pair->two->path, 0);
708 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
709 free(new_path);
710 }
711
712 static void conflict_rename_rename_2(struct rename *ren1,
713 const char *branch1,
714 struct rename *ren2,
715 const char *branch2)
716 {
717 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
718 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
719 output(1, "Renaming %s to %s and %s to %s instead",
720 ren1->pair->one->path, new_path1,
721 ren2->pair->one->path, new_path2);
722 remove_file(0, ren1->pair->two->path, 0);
723 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
724 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
725 free(new_path2);
726 free(new_path1);
727 }
728
729 static int process_renames(struct path_list *a_renames,
730 struct path_list *b_renames,
731 const char *a_branch,
732 const char *b_branch)
733 {
734 int clean_merge = 1, i, j;
735 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
736 const struct rename *sre;
737
738 for (i = 0; i < a_renames->nr; i++) {
739 sre = a_renames->items[i].util;
740 path_list_insert(sre->pair->two->path, &a_by_dst)->util
741 = sre->dst_entry;
742 }
743 for (i = 0; i < b_renames->nr; i++) {
744 sre = b_renames->items[i].util;
745 path_list_insert(sre->pair->two->path, &b_by_dst)->util
746 = sre->dst_entry;
747 }
748
749 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
750 int compare;
751 char *src;
752 struct path_list *renames1, *renames2, *renames2Dst;
753 struct rename *ren1 = NULL, *ren2 = NULL;
754 const char *branch1, *branch2;
755 const char *ren1_src, *ren1_dst;
756
757 if (i >= a_renames->nr) {
758 compare = 1;
759 ren2 = b_renames->items[j++].util;
760 } else if (j >= b_renames->nr) {
761 compare = -1;
762 ren1 = a_renames->items[i++].util;
763 } else {
764 compare = strcmp(a_renames->items[i].path,
765 b_renames->items[j].path);
766 if (compare <= 0)
767 ren1 = a_renames->items[i++].util;
768 if (compare >= 0)
769 ren2 = b_renames->items[j++].util;
770 }
771
772 /* TODO: refactor, so that 1/2 are not needed */
773 if (ren1) {
774 renames1 = a_renames;
775 renames2 = b_renames;
776 renames2Dst = &b_by_dst;
777 branch1 = a_branch;
778 branch2 = b_branch;
779 } else {
780 struct rename *tmp;
781 renames1 = b_renames;
782 renames2 = a_renames;
783 renames2Dst = &a_by_dst;
784 branch1 = b_branch;
785 branch2 = a_branch;
786 tmp = ren2;
787 ren2 = ren1;
788 ren1 = tmp;
789 }
790 src = ren1->pair->one->path;
791
792 ren1->dst_entry->processed = 1;
793 ren1->src_entry->processed = 1;
794
795 if (ren1->processed)
796 continue;
797 ren1->processed = 1;
798
799 ren1_src = ren1->pair->one->path;
800 ren1_dst = ren1->pair->two->path;
801
802 if (ren2) {
803 const char *ren2_src = ren2->pair->one->path;
804 const char *ren2_dst = ren2->pair->two->path;
805 /* Renamed in 1 and renamed in 2 */
806 if (strcmp(ren1_src, ren2_src) != 0)
807 die("ren1.src != ren2.src");
808 ren2->dst_entry->processed = 1;
809 ren2->processed = 1;
810 if (strcmp(ren1_dst, ren2_dst) != 0) {
811 clean_merge = 0;
812 output(1, "CONFLICT (rename/rename): "
813 "Rename %s->%s in branch %s "
814 "rename %s->%s in %s",
815 src, ren1_dst, branch1,
816 src, ren2_dst, branch2);
817 conflict_rename_rename(ren1, branch1, ren2, branch2);
818 } else {
819 struct merge_file_info mfi;
820 remove_file(1, ren1_src, 1);
821 mfi = merge_file(ren1->pair->one,
822 ren1->pair->two,
823 ren2->pair->two,
824 branch1,
825 branch2);
826 if (mfi.merge || !mfi.clean)
827 output(1, "Renaming %s->%s", src, ren1_dst);
828
829 if (mfi.merge)
830 output(2, "Auto-merging %s", ren1_dst);
831
832 if (!mfi.clean) {
833 output(1, "CONFLICT (content): merge conflict in %s",
834 ren1_dst);
835 clean_merge = 0;
836
837 if (!index_only)
838 update_stages(ren1_dst,
839 ren1->pair->one,
840 ren1->pair->two,
841 ren2->pair->two,
842 1 /* clear */);
843 }
844 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
845 }
846 } else {
847 /* Renamed in 1, maybe changed in 2 */
848 struct path_list_item *item;
849 /* we only use sha1 and mode of these */
850 struct diff_filespec src_other, dst_other;
851 int try_merge, stage = a_renames == renames1 ? 3: 2;
852
853 remove_file(1, ren1_src, index_only);
854
855 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
856 src_other.mode = ren1->src_entry->stages[stage].mode;
857 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
858 dst_other.mode = ren1->dst_entry->stages[stage].mode;
859
860 try_merge = 0;
861
862 if (path_list_has_path(&current_directory_set, ren1_dst)) {
863 clean_merge = 0;
864 output(1, "CONFLICT (rename/directory): Rename %s->%s in %s "
865 " directory %s added in %s",
866 ren1_src, ren1_dst, branch1,
867 ren1_dst, branch2);
868 conflict_rename_dir(ren1, branch1);
869 } else if (sha_eq(src_other.sha1, null_sha1)) {
870 clean_merge = 0;
871 output(1, "CONFLICT (rename/delete): Rename %s->%s in %s "
872 "and deleted in %s",
873 ren1_src, ren1_dst, branch1,
874 branch2);
875 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
876 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
877 const char *new_path;
878 clean_merge = 0;
879 try_merge = 1;
880 output(1, "CONFLICT (rename/add): Rename %s->%s in %s. "
881 "%s added in %s",
882 ren1_src, ren1_dst, branch1,
883 ren1_dst, branch2);
884 new_path = unique_path(ren1_dst, branch2);
885 output(1, "Adding as %s instead", new_path);
886 update_file(0, dst_other.sha1, dst_other.mode, new_path);
887 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
888 ren2 = item->util;
889 clean_merge = 0;
890 ren2->processed = 1;
891 output(1, "CONFLICT (rename/rename): Rename %s->%s in %s. "
892 "Rename %s->%s in %s",
893 ren1_src, ren1_dst, branch1,
894 ren2->pair->one->path, ren2->pair->two->path, branch2);
895 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
896 } else
897 try_merge = 1;
898
899 if (try_merge) {
900 struct diff_filespec *o, *a, *b;
901 struct merge_file_info mfi;
902 src_other.path = (char *)ren1_src;
903
904 o = ren1->pair->one;
905 if (a_renames == renames1) {
906 a = ren1->pair->two;
907 b = &src_other;
908 } else {
909 b = ren1->pair->two;
910 a = &src_other;
911 }
912 mfi = merge_file(o, a, b,
913 a_branch, b_branch);
914
915 if (mfi.merge || !mfi.clean)
916 output(1, "Renaming %s => %s", ren1_src, ren1_dst);
917 if (mfi.merge)
918 output(2, "Auto-merging %s", ren1_dst);
919 if (!mfi.clean) {
920 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
921 ren1_dst);
922 clean_merge = 0;
923
924 if (!index_only)
925 update_stages(ren1_dst,
926 o, a, b, 1);
927 }
928 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
929 }
930 }
931 }
932 path_list_clear(&a_by_dst, 0);
933 path_list_clear(&b_by_dst, 0);
934
935 return clean_merge;
936 }
937
938 static unsigned char *has_sha(const unsigned char *sha)
939 {
940 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
941 }
942
943 /* Per entry merge function */
944 static int process_entry(const char *path, struct stage_data *entry,
945 const char *branch1,
946 const char *branch2)
947 {
948 /*
949 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
950 print_index_entry("\tpath: ", entry);
951 */
952 int clean_merge = 1;
953 unsigned char *o_sha = has_sha(entry->stages[1].sha);
954 unsigned char *a_sha = has_sha(entry->stages[2].sha);
955 unsigned char *b_sha = has_sha(entry->stages[3].sha);
956 unsigned o_mode = entry->stages[1].mode;
957 unsigned a_mode = entry->stages[2].mode;
958 unsigned b_mode = entry->stages[3].mode;
959
960 if (o_sha && (!a_sha || !b_sha)) {
961 /* Case A: Deleted in one */
962 if ((!a_sha && !b_sha) ||
963 (sha_eq(a_sha, o_sha) && !b_sha) ||
964 (!a_sha && sha_eq(b_sha, o_sha))) {
965 /* Deleted in both or deleted in one and
966 * unchanged in the other */
967 if (a_sha)
968 output(2, "Removing %s", path);
969 /* do not touch working file if it did not exist */
970 remove_file(1, path, !a_sha);
971 } else {
972 /* Deleted in one and changed in the other */
973 clean_merge = 0;
974 if (!a_sha) {
975 output(1, "CONFLICT (delete/modify): %s deleted in %s "
976 "and modified in %s. Version %s of %s left in tree.",
977 path, branch1,
978 branch2, branch2, path);
979 update_file(0, b_sha, b_mode, path);
980 } else {
981 output(1, "CONFLICT (delete/modify): %s deleted in %s "
982 "and modified in %s. Version %s of %s left in tree.",
983 path, branch2,
984 branch1, branch1, path);
985 update_file(0, a_sha, a_mode, path);
986 }
987 }
988
989 } else if ((!o_sha && a_sha && !b_sha) ||
990 (!o_sha && !a_sha && b_sha)) {
991 /* Case B: Added in one. */
992 const char *add_branch;
993 const char *other_branch;
994 unsigned mode;
995 const unsigned char *sha;
996 const char *conf;
997
998 if (a_sha) {
999 add_branch = branch1;
1000 other_branch = branch2;
1001 mode = a_mode;
1002 sha = a_sha;
1003 conf = "file/directory";
1004 } else {
1005 add_branch = branch2;
1006 other_branch = branch1;
1007 mode = b_mode;
1008 sha = b_sha;
1009 conf = "directory/file";
1010 }
1011 if (path_list_has_path(&current_directory_set, path)) {
1012 const char *new_path = unique_path(path, add_branch);
1013 clean_merge = 0;
1014 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1015 "Adding %s as %s",
1016 conf, path, other_branch, path, new_path);
1017 remove_file(0, path, 0);
1018 update_file(0, sha, mode, new_path);
1019 } else {
1020 output(2, "Adding %s", path);
1021 update_file(1, sha, mode, path);
1022 }
1023 } else if (a_sha && b_sha) {
1024 /* Case C: Added in both (check for same permissions) and */
1025 /* case D: Modified in both, but differently. */
1026 const char *reason = "content";
1027 struct merge_file_info mfi;
1028 struct diff_filespec o, a, b;
1029
1030 if (!o_sha) {
1031 reason = "add/add";
1032 o_sha = (unsigned char *)null_sha1;
1033 }
1034 output(2, "Auto-merging %s", path);
1035 o.path = a.path = b.path = (char *)path;
1036 hashcpy(o.sha1, o_sha);
1037 o.mode = o_mode;
1038 hashcpy(a.sha1, a_sha);
1039 a.mode = a_mode;
1040 hashcpy(b.sha1, b_sha);
1041 b.mode = b_mode;
1042
1043 mfi = merge_file(&o, &a, &b,
1044 branch1, branch2);
1045
1046 if (mfi.clean)
1047 update_file(1, mfi.sha, mfi.mode, path);
1048 else {
1049 clean_merge = 0;
1050 output(1, "CONFLICT (%s): Merge conflict in %s",
1051 reason, path);
1052
1053 if (index_only)
1054 update_file(0, mfi.sha, mfi.mode, path);
1055 else
1056 update_file_flags(mfi.sha, mfi.mode, path,
1057 0 /* update_cache */, 1 /* update_working_directory */);
1058 }
1059 } else
1060 die("Fatal merge failure, shouldn't happen.");
1061
1062 return clean_merge;
1063 }
1064
1065 static int merge_trees(struct tree *head,
1066 struct tree *merge,
1067 struct tree *common,
1068 const char *branch1,
1069 const char *branch2,
1070 struct tree **result)
1071 {
1072 int code, clean;
1073 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1074 output(0, "Already uptodate!");
1075 *result = head;
1076 return 1;
1077 }
1078
1079 code = git_merge_trees(index_only, common, head, merge);
1080
1081 if (code != 0)
1082 die("merging of trees %s and %s failed",
1083 sha1_to_hex(head->object.sha1),
1084 sha1_to_hex(merge->object.sha1));
1085
1086 if (unmerged_index()) {
1087 struct path_list *entries, *re_head, *re_merge;
1088 int i;
1089 path_list_clear(&current_file_set, 1);
1090 path_list_clear(&current_directory_set, 1);
1091 get_files_dirs(head);
1092 get_files_dirs(merge);
1093
1094 entries = get_unmerged();
1095 re_head = get_renames(head, common, head, merge, entries);
1096 re_merge = get_renames(merge, common, head, merge, entries);
1097 clean = process_renames(re_head, re_merge,
1098 branch1, branch2);
1099 for (i = 0; i < entries->nr; i++) {
1100 const char *path = entries->items[i].path;
1101 struct stage_data *e = entries->items[i].util;
1102 if (e->processed)
1103 continue;
1104 if (!process_entry(path, e, branch1, branch2))
1105 clean = 0;
1106 }
1107
1108 path_list_clear(re_merge, 0);
1109 path_list_clear(re_head, 0);
1110 path_list_clear(entries, 1);
1111
1112 }
1113 else
1114 clean = 1;
1115
1116 if (index_only)
1117 *result = git_write_tree();
1118
1119 return clean;
1120 }
1121
1122 static struct commit_list *reverse_commit_list(struct commit_list *list)
1123 {
1124 struct commit_list *next = NULL, *current, *backup;
1125 for (current = list; current; current = backup) {
1126 backup = current->next;
1127 current->next = next;
1128 next = current;
1129 }
1130 return next;
1131 }
1132
1133 /*
1134 * Merge the commits h1 and h2, return the resulting virtual
1135 * commit object and a flag indicating the cleaness of the merge.
1136 */
1137 static int merge(struct commit *h1,
1138 struct commit *h2,
1139 const char *branch1,
1140 const char *branch2,
1141 struct commit_list *ca,
1142 struct commit **result)
1143 {
1144 struct commit_list *iter;
1145 struct commit *merged_common_ancestors;
1146 struct tree *mrtree;
1147 int clean;
1148
1149 if (show(4)) {
1150 output(4, "Merging:");
1151 output_commit_title(h1);
1152 output_commit_title(h2);
1153 }
1154
1155 if (!ca) {
1156 ca = get_merge_bases(h1, h2, 1);
1157 ca = reverse_commit_list(ca);
1158 }
1159
1160 if (show(5)) {
1161 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1162 for (iter = ca; iter; iter = iter->next)
1163 output_commit_title(iter->item);
1164 }
1165
1166 merged_common_ancestors = pop_commit(&ca);
1167 if (merged_common_ancestors == NULL) {
1168 /* if there is no common ancestor, make an empty tree */
1169 struct tree *tree = xcalloc(1, sizeof(struct tree));
1170
1171 tree->object.parsed = 1;
1172 tree->object.type = OBJ_TREE;
1173 write_sha1_file(NULL, 0, tree_type, tree->object.sha1);
1174 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1175 }
1176
1177 for (iter = ca; iter; iter = iter->next) {
1178 call_depth++;
1179 /*
1180 * When the merge fails, the result contains files
1181 * with conflict markers. The cleanness flag is
1182 * ignored, it was never acutally used, as result of
1183 * merge_trees has always overwritten it: the commited
1184 * "conflicts" were already resolved.
1185 */
1186 discard_cache();
1187 merge(merged_common_ancestors, iter->item,
1188 "Temporary merge branch 1",
1189 "Temporary merge branch 2",
1190 NULL,
1191 &merged_common_ancestors);
1192 call_depth--;
1193
1194 if (!merged_common_ancestors)
1195 die("merge returned no commit");
1196 }
1197
1198 discard_cache();
1199 if (!call_depth) {
1200 read_cache();
1201 index_only = 0;
1202 } else
1203 index_only = 1;
1204
1205 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1206 branch1, branch2, &mrtree);
1207
1208 if (index_only) {
1209 *result = make_virtual_commit(mrtree, "merged tree");
1210 commit_list_insert(h1, &(*result)->parents);
1211 commit_list_insert(h2, &(*result)->parents->next);
1212 }
1213 flush_output();
1214 return clean;
1215 }
1216
1217 static const char *better_branch_name(const char *branch)
1218 {
1219 static char githead_env[8 + 40 + 1];
1220 char *name;
1221
1222 if (strlen(branch) != 40)
1223 return branch;
1224 sprintf(githead_env, "GITHEAD_%s", branch);
1225 name = getenv(githead_env);
1226 return name ? name : branch;
1227 }
1228
1229 static struct commit *get_ref(const char *ref)
1230 {
1231 unsigned char sha1[20];
1232 struct object *object;
1233
1234 if (get_sha1(ref, sha1))
1235 die("Could not resolve ref '%s'", ref);
1236 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1237 if (object->type == OBJ_TREE)
1238 return make_virtual_commit((struct tree*)object,
1239 better_branch_name(ref));
1240 if (object->type != OBJ_COMMIT)
1241 return NULL;
1242 if (parse_commit((struct commit *)object))
1243 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1244 return (struct commit *)object;
1245 }
1246
1247 static int merge_config(const char *var, const char *value)
1248 {
1249 if (!strcasecmp(var, "merge.verbosity")) {
1250 verbosity = git_config_int(var, value);
1251 return 0;
1252 }
1253 return git_default_config(var, value);
1254 }
1255
1256 int main(int argc, char *argv[])
1257 {
1258 static const char *bases[20];
1259 static unsigned bases_count = 0;
1260 int i, clean;
1261 const char *branch1, *branch2;
1262 struct commit *result, *h1, *h2;
1263 struct commit_list *ca = NULL;
1264 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1265 int index_fd;
1266
1267 git_config(merge_config);
1268 if (getenv("GIT_MERGE_VERBOSITY"))
1269 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1270
1271 if (argc < 4)
1272 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1273
1274 for (i = 1; i < argc; ++i) {
1275 if (!strcmp(argv[i], "--"))
1276 break;
1277 if (bases_count < sizeof(bases)/sizeof(*bases))
1278 bases[bases_count++] = argv[i];
1279 }
1280 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1281 die("Not handling anything other than two heads merge.");
1282
1283 branch1 = argv[++i];
1284 branch2 = argv[++i];
1285
1286 h1 = get_ref(branch1);
1287 h2 = get_ref(branch2);
1288
1289 branch1 = better_branch_name(branch1);
1290 branch2 = better_branch_name(branch2);
1291 if (verbosity >= 5)
1292 buffer_output = 0;
1293 if (show(3))
1294 printf("Merging %s with %s\n", branch1, branch2);
1295
1296 index_fd = hold_lock_file_for_update(lock, get_index_file(), 1);
1297
1298 for (i = 0; i < bases_count; i++) {
1299 struct commit *ancestor = get_ref(bases[i]);
1300 ca = commit_list_insert(ancestor, &ca);
1301 }
1302 clean = merge(h1, h2, branch1, branch2, ca, &result);
1303
1304 if (active_cache_changed &&
1305 (write_cache(index_fd, active_cache, active_nr) ||
1306 close(index_fd) || commit_lock_file(lock)))
1307 die ("unable to write %s", get_index_file());
1308
1309 return clean ? 0: 1;
1310 }