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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"
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 */
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 }
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 }
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 }
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 };
70 struct output_buffer
71 {
72 struct output_buffer *next;
73 char *str;
74 };
76 static struct path_list current_file_set = {NULL, 0, 0, 1};
77 static struct path_list current_directory_set = {NULL, 0, 0, 1};
79 static int call_depth = 0;
80 static int verbosity = 2;
81 static int buffer_output = 1;
82 static int do_progress = 1;
83 static unsigned last_percent;
84 static unsigned merged_cnt;
85 static unsigned total_cnt;
86 static volatile sig_atomic_t progress_update;
87 static struct output_buffer *output_list, *output_end;
89 static int show (int v)
90 {
91 return (!call_depth && verbosity >= v) || verbosity >= 5;
92 }
94 static void output(int v, const char *fmt, ...)
95 {
96 va_list args;
97 va_start(args, fmt);
98 if (buffer_output && show(v)) {
99 struct output_buffer *b = xmalloc(sizeof(*b));
100 nfvasprintf(&b->str, fmt, args);
101 b->next = NULL;
102 if (output_end)
103 output_end->next = b;
104 else
105 output_list = b;
106 output_end = b;
107 } else if (show(v)) {
108 int i;
109 for (i = call_depth; i--;)
110 fputs(" ", stdout);
111 vfprintf(stdout, fmt, args);
112 fputc('\n', stdout);
113 }
114 va_end(args);
115 }
117 static void flush_output()
118 {
119 struct output_buffer *b, *n;
120 for (b = output_list; b; b = n) {
121 int i;
122 for (i = call_depth; i--;)
123 fputs(" ", stdout);
124 fputs(b->str, stdout);
125 fputc('\n', stdout);
126 n = b->next;
127 free(b->str);
128 free(b);
129 }
130 output_list = NULL;
131 output_end = NULL;
132 }
134 static void output_commit_title(struct commit *commit)
135 {
136 int i;
137 flush_output();
138 for (i = call_depth; i--;)
139 fputs(" ", stdout);
140 if (commit->util)
141 printf("virtual %s\n", (char *)commit->util);
142 else {
143 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
144 if (parse_commit(commit) != 0)
145 printf("(bad commit)\n");
146 else {
147 const char *s;
148 int len;
149 for (s = commit->buffer; *s; s++)
150 if (*s == '\n' && s[1] == '\n') {
151 s += 2;
152 break;
153 }
154 for (len = 0; s[len] && '\n' != s[len]; len++)
155 ; /* do nothing */
156 printf("%.*s\n", len, s);
157 }
158 }
159 }
161 static void progress_interval(int signum)
162 {
163 progress_update = 1;
164 }
166 static void setup_progress_signal(void)
167 {
168 struct sigaction sa;
169 struct itimerval v;
171 memset(&sa, 0, sizeof(sa));
172 sa.sa_handler = progress_interval;
173 sigemptyset(&sa.sa_mask);
174 sa.sa_flags = SA_RESTART;
175 sigaction(SIGALRM, &sa, NULL);
177 v.it_interval.tv_sec = 1;
178 v.it_interval.tv_usec = 0;
179 v.it_value = v.it_interval;
180 setitimer(ITIMER_REAL, &v, NULL);
181 }
183 static void display_progress()
184 {
185 unsigned percent = total_cnt ? merged_cnt * 100 / total_cnt : 0;
186 if (progress_update || percent != last_percent) {
187 fprintf(stderr, "%4u%% (%u/%u) done\r",
188 percent, merged_cnt, total_cnt);
189 progress_update = 0;
190 last_percent = percent;
191 }
192 }
194 static struct cache_entry *make_cache_entry(unsigned int mode,
195 const unsigned char *sha1, const char *path, int stage, int refresh)
196 {
197 int size, len;
198 struct cache_entry *ce;
200 if (!verify_path(path))
201 return NULL;
203 len = strlen(path);
204 size = cache_entry_size(len);
205 ce = xcalloc(1, size);
207 hashcpy(ce->sha1, sha1);
208 memcpy(ce->name, path, len);
209 ce->ce_flags = create_ce_flags(len, stage);
210 ce->ce_mode = create_ce_mode(mode);
212 if (refresh)
213 return refresh_cache_entry(ce, 0);
215 return ce;
216 }
218 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
219 const char *path, int stage, int refresh, int options)
220 {
221 struct cache_entry *ce;
222 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
223 if (!ce)
224 return error("cache_addinfo failed: %s", strerror(cache_errno));
225 return add_cache_entry(ce, options);
226 }
228 /*
229 * This is a global variable which is used in a number of places but
230 * only written to in the 'merge' function.
231 *
232 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
233 * don't update the working directory.
234 * 0 => Leave unmerged entries in the cache and update
235 * the working directory.
236 */
237 static int index_only = 0;
239 static int git_merge_trees(int index_only,
240 struct tree *common,
241 struct tree *head,
242 struct tree *merge)
243 {
244 int rc;
245 struct object_list *trees = NULL;
246 struct unpack_trees_options opts;
248 memset(&opts, 0, sizeof(opts));
249 if (index_only)
250 opts.index_only = 1;
251 else
252 opts.update = 1;
253 opts.merge = 1;
254 opts.head_idx = 2;
255 opts.fn = threeway_merge;
257 object_list_append(&common->object, &trees);
258 object_list_append(&head->object, &trees);
259 object_list_append(&merge->object, &trees);
261 rc = unpack_trees(trees, &opts);
262 cache_tree_free(&active_cache_tree);
263 return rc;
264 }
266 static int unmerged_index(void)
267 {
268 int i;
269 for (i = 0; i < active_nr; i++) {
270 struct cache_entry *ce = active_cache[i];
271 if (ce_stage(ce))
272 return 1;
273 }
274 return 0;
275 }
277 static struct tree *git_write_tree(void)
278 {
279 struct tree *result = NULL;
281 if (unmerged_index()) {
282 int i;
283 output(0, "There are unmerged index entries:");
284 for (i = 0; i < active_nr; i++) {
285 struct cache_entry *ce = active_cache[i];
286 if (ce_stage(ce))
287 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
288 }
289 return NULL;
290 }
292 if (!active_cache_tree)
293 active_cache_tree = cache_tree();
295 if (!cache_tree_fully_valid(active_cache_tree) &&
296 cache_tree_update(active_cache_tree,
297 active_cache, active_nr, 0, 0) < 0)
298 die("error building trees");
300 result = lookup_tree(active_cache_tree->sha1);
302 return result;
303 }
305 static int save_files_dirs(const unsigned char *sha1,
306 const char *base, int baselen, const char *path,
307 unsigned int mode, int stage)
308 {
309 int len = strlen(path);
310 char *newpath = xmalloc(baselen + len + 1);
311 memcpy(newpath, base, baselen);
312 memcpy(newpath + baselen, path, len);
313 newpath[baselen + len] = '\0';
315 if (S_ISDIR(mode))
316 path_list_insert(newpath, ¤t_directory_set);
317 else
318 path_list_insert(newpath, ¤t_file_set);
319 free(newpath);
321 return READ_TREE_RECURSIVE;
322 }
324 static int get_files_dirs(struct tree *tree)
325 {
326 int n;
327 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
328 return 0;
329 n = current_file_set.nr + current_directory_set.nr;
330 return n;
331 }
333 /*
334 * Returns a index_entry instance which doesn't have to correspond to
335 * a real cache entry in Git's index.
336 */
337 static struct stage_data *insert_stage_data(const char *path,
338 struct tree *o, struct tree *a, struct tree *b,
339 struct path_list *entries)
340 {
341 struct path_list_item *item;
342 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
343 get_tree_entry(o->object.sha1, path,
344 e->stages[1].sha, &e->stages[1].mode);
345 get_tree_entry(a->object.sha1, path,
346 e->stages[2].sha, &e->stages[2].mode);
347 get_tree_entry(b->object.sha1, path,
348 e->stages[3].sha, &e->stages[3].mode);
349 item = path_list_insert(path, entries);
350 item->util = e;
351 return e;
352 }
354 /*
355 * Create a dictionary mapping file names to stage_data objects. The
356 * dictionary contains one entry for every path with a non-zero stage entry.
357 */
358 static struct path_list *get_unmerged(void)
359 {
360 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
361 int i;
363 unmerged->strdup_paths = 1;
364 total_cnt += active_nr;
366 for (i = 0; i < active_nr; i++, merged_cnt++) {
367 struct path_list_item *item;
368 struct stage_data *e;
369 struct cache_entry *ce = active_cache[i];
370 if (do_progress)
371 display_progress();
372 if (!ce_stage(ce))
373 continue;
375 item = path_list_lookup(ce->name, unmerged);
376 if (!item) {
377 item = path_list_insert(ce->name, unmerged);
378 item->util = xcalloc(1, sizeof(struct stage_data));
379 }
380 e = item->util;
381 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
382 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
383 }
385 return unmerged;
386 }
388 struct rename
389 {
390 struct diff_filepair *pair;
391 struct stage_data *src_entry;
392 struct stage_data *dst_entry;
393 unsigned processed:1;
394 };
396 /*
397 * Get information of all renames which occurred between 'o_tree' and
398 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
399 * 'b_tree') to be able to associate the correct cache entries with
400 * the rename information. 'tree' is always equal to either a_tree or b_tree.
401 */
402 static struct path_list *get_renames(struct tree *tree,
403 struct tree *o_tree,
404 struct tree *a_tree,
405 struct tree *b_tree,
406 struct path_list *entries)
407 {
408 int i;
409 struct path_list *renames;
410 struct diff_options opts;
412 renames = xcalloc(1, sizeof(struct path_list));
413 diff_setup(&opts);
414 opts.recursive = 1;
415 opts.detect_rename = DIFF_DETECT_RENAME;
416 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
417 if (diff_setup_done(&opts) < 0)
418 die("diff setup failed");
419 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
420 diffcore_std(&opts);
421 for (i = 0; i < diff_queued_diff.nr; ++i) {
422 struct path_list_item *item;
423 struct rename *re;
424 struct diff_filepair *pair = diff_queued_diff.queue[i];
425 if (pair->status != 'R') {
426 diff_free_filepair(pair);
427 continue;
428 }
429 re = xmalloc(sizeof(*re));
430 re->processed = 0;
431 re->pair = pair;
432 item = path_list_lookup(re->pair->one->path, entries);
433 if (!item)
434 re->src_entry = insert_stage_data(re->pair->one->path,
435 o_tree, a_tree, b_tree, entries);
436 else
437 re->src_entry = item->util;
439 item = path_list_lookup(re->pair->two->path, entries);
440 if (!item)
441 re->dst_entry = insert_stage_data(re->pair->two->path,
442 o_tree, a_tree, b_tree, entries);
443 else
444 re->dst_entry = item->util;
445 item = path_list_insert(pair->one->path, renames);
446 item->util = re;
447 }
448 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
449 diff_queued_diff.nr = 0;
450 diff_flush(&opts);
451 return renames;
452 }
454 static int update_stages(const char *path, struct diff_filespec *o,
455 struct diff_filespec *a, struct diff_filespec *b,
456 int clear)
457 {
458 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
459 if (clear)
460 if (remove_file_from_cache(path))
461 return -1;
462 if (o)
463 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
464 return -1;
465 if (a)
466 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
467 return -1;
468 if (b)
469 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
470 return -1;
471 return 0;
472 }
474 static int remove_path(const char *name)
475 {
476 int ret, len;
477 char *slash, *dirs;
479 ret = unlink(name);
480 if (ret)
481 return ret;
482 len = strlen(name);
483 dirs = xmalloc(len+1);
484 memcpy(dirs, name, len);
485 dirs[len] = '\0';
486 while ((slash = strrchr(name, '/'))) {
487 *slash = '\0';
488 len = slash - name;
489 if (rmdir(name) != 0)
490 break;
491 }
492 free(dirs);
493 return ret;
494 }
496 static int remove_file(int clean, const char *path, int no_wd)
497 {
498 int update_cache = index_only || clean;
499 int update_working_directory = !index_only && !no_wd;
501 if (update_cache) {
502 if (remove_file_from_cache(path))
503 return -1;
504 }
505 if (update_working_directory) {
506 unlink(path);
507 if (errno != ENOENT || errno != EISDIR)
508 return -1;
509 remove_path(path);
510 }
511 return 0;
512 }
514 static char *unique_path(const char *path, const char *branch)
515 {
516 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
517 int suffix = 0;
518 struct stat st;
519 char *p = newpath + strlen(path);
520 strcpy(newpath, path);
521 *(p++) = '~';
522 strcpy(p, branch);
523 for (; *p; ++p)
524 if ('/' == *p)
525 *p = '_';
526 while (path_list_has_path(¤t_file_set, newpath) ||
527 path_list_has_path(¤t_directory_set, newpath) ||
528 lstat(newpath, &st) == 0)
529 sprintf(p, "_%d", suffix++);
531 path_list_insert(newpath, ¤t_file_set);
532 return newpath;
533 }
535 static int mkdir_p(const char *path, unsigned long mode)
536 {
537 /* path points to cache entries, so xstrdup before messing with it */
538 char *buf = xstrdup(path);
539 int result = safe_create_leading_directories(buf);
540 free(buf);
541 return result;
542 }
544 static void flush_buffer(int fd, const char *buf, unsigned long size)
545 {
546 while (size > 0) {
547 long ret = write_in_full(fd, buf, size);
548 if (ret < 0) {
549 /* Ignore epipe */
550 if (errno == EPIPE)
551 break;
552 die("merge-recursive: %s", strerror(errno));
553 } else if (!ret) {
554 die("merge-recursive: disk full?");
555 }
556 size -= ret;
557 buf += ret;
558 }
559 }
561 static void update_file_flags(const unsigned char *sha,
562 unsigned mode,
563 const char *path,
564 int update_cache,
565 int update_wd)
566 {
567 if (index_only)
568 update_wd = 0;
570 if (update_wd) {
571 enum object_type type;
572 void *buf;
573 unsigned long size;
575 buf = read_sha1_file(sha, &type, &size);
576 if (!buf)
577 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
578 if (type != OBJ_BLOB)
579 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
581 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
582 int fd;
583 if (mkdir_p(path, 0777))
584 die("failed to create path %s: %s", path, strerror(errno));
585 unlink(path);
586 if (mode & 0100)
587 mode = 0777;
588 else
589 mode = 0666;
590 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
591 if (fd < 0)
592 die("failed to open %s: %s", path, strerror(errno));
593 flush_buffer(fd, buf, size);
594 close(fd);
595 } else if (S_ISLNK(mode)) {
596 char *lnk = xmalloc(size + 1);
597 memcpy(lnk, buf, size);
598 lnk[size] = '\0';
599 mkdir_p(path, 0777);
600 unlink(path);
601 symlink(lnk, path);
602 free(lnk);
603 } else
604 die("do not know what to do with %06o %s '%s'",
605 mode, sha1_to_hex(sha), path);
606 }
607 if (update_cache)
608 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
609 }
611 static void update_file(int clean,
612 const unsigned char *sha,
613 unsigned mode,
614 const char *path)
615 {
616 update_file_flags(sha, mode, path, index_only || clean, !index_only);
617 }
619 /* Low level file merging, update and removal */
621 struct merge_file_info
622 {
623 unsigned char sha[20];
624 unsigned mode;
625 unsigned clean:1,
626 merge:1;
627 };
629 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
630 {
631 unsigned long size;
632 enum object_type type;
634 if (!hashcmp(sha1, null_sha1)) {
635 mm->ptr = xstrdup("");
636 mm->size = 0;
637 return;
638 }
640 mm->ptr = read_sha1_file(sha1, &type, &size);
641 if (!mm->ptr || type != OBJ_BLOB)
642 die("unable to read blob object %s", sha1_to_hex(sha1));
643 mm->size = size;
644 }
646 static struct merge_file_info merge_file(struct diff_filespec *o,
647 struct diff_filespec *a, struct diff_filespec *b,
648 const char *branch1, const char *branch2)
649 {
650 struct merge_file_info result;
651 result.merge = 0;
652 result.clean = 1;
654 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
655 result.clean = 0;
656 if (S_ISREG(a->mode)) {
657 result.mode = a->mode;
658 hashcpy(result.sha, a->sha1);
659 } else {
660 result.mode = b->mode;
661 hashcpy(result.sha, b->sha1);
662 }
663 } else {
664 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
665 result.merge = 1;
667 result.mode = a->mode == o->mode ? b->mode: a->mode;
669 if (sha_eq(a->sha1, o->sha1))
670 hashcpy(result.sha, b->sha1);
671 else if (sha_eq(b->sha1, o->sha1))
672 hashcpy(result.sha, a->sha1);
673 else if (S_ISREG(a->mode)) {
674 mmfile_t orig, src1, src2;
675 mmbuffer_t result_buf;
676 xpparam_t xpp;
677 char *name1, *name2;
678 int merge_status;
680 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
681 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
683 fill_mm(o->sha1, &orig);
684 fill_mm(a->sha1, &src1);
685 fill_mm(b->sha1, &src2);
687 memset(&xpp, 0, sizeof(xpp));
688 merge_status = xdl_merge(&orig,
689 &src1, name1,
690 &src2, name2,
691 &xpp, XDL_MERGE_ZEALOUS,
692 &result_buf);
693 free(name1);
694 free(name2);
695 free(orig.ptr);
696 free(src1.ptr);
697 free(src2.ptr);
699 if ((merge_status < 0) || !result_buf.ptr)
700 die("Failed to execute internal merge");
702 if (write_sha1_file(result_buf.ptr, result_buf.size,
703 blob_type, result.sha))
704 die("Unable to add %s to database",
705 a->path);
707 free(result_buf.ptr);
708 result.clean = (merge_status == 0);
709 } else {
710 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
711 die("cannot merge modes?");
713 hashcpy(result.sha, a->sha1);
715 if (!sha_eq(a->sha1, b->sha1))
716 result.clean = 0;
717 }
718 }
720 return result;
721 }
723 static void conflict_rename_rename(struct rename *ren1,
724 const char *branch1,
725 struct rename *ren2,
726 const char *branch2)
727 {
728 char *del[2];
729 int delp = 0;
730 const char *ren1_dst = ren1->pair->two->path;
731 const char *ren2_dst = ren2->pair->two->path;
732 const char *dst_name1 = ren1_dst;
733 const char *dst_name2 = ren2_dst;
734 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
735 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
736 output(1, "%s is a directory in %s added as %s instead",
737 ren1_dst, branch2, dst_name1);
738 remove_file(0, ren1_dst, 0);
739 }
740 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
741 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
742 output(1, "%s is a directory in %s added as %s instead",
743 ren2_dst, branch1, dst_name2);
744 remove_file(0, ren2_dst, 0);
745 }
746 if (index_only) {
747 remove_file_from_cache(dst_name1);
748 remove_file_from_cache(dst_name2);
749 /*
750 * Uncomment to leave the conflicting names in the resulting tree
751 *
752 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
753 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
754 */
755 } else {
756 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
757 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
758 }
759 while (delp--)
760 free(del[delp]);
761 }
763 static void conflict_rename_dir(struct rename *ren1,
764 const char *branch1)
765 {
766 char *new_path = unique_path(ren1->pair->two->path, branch1);
767 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
768 remove_file(0, ren1->pair->two->path, 0);
769 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
770 free(new_path);
771 }
773 static void conflict_rename_rename_2(struct rename *ren1,
774 const char *branch1,
775 struct rename *ren2,
776 const char *branch2)
777 {
778 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
779 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
780 output(1, "Renamed %s to %s and %s to %s instead",
781 ren1->pair->one->path, new_path1,
782 ren2->pair->one->path, new_path2);
783 remove_file(0, ren1->pair->two->path, 0);
784 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
785 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
786 free(new_path2);
787 free(new_path1);
788 }
790 static int process_renames(struct path_list *a_renames,
791 struct path_list *b_renames,
792 const char *a_branch,
793 const char *b_branch)
794 {
795 int clean_merge = 1, i, j;
796 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
797 const struct rename *sre;
799 for (i = 0; i < a_renames->nr; i++) {
800 sre = a_renames->items[i].util;
801 path_list_insert(sre->pair->two->path, &a_by_dst)->util
802 = sre->dst_entry;
803 }
804 for (i = 0; i < b_renames->nr; i++) {
805 sre = b_renames->items[i].util;
806 path_list_insert(sre->pair->two->path, &b_by_dst)->util
807 = sre->dst_entry;
808 }
810 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
811 int compare;
812 char *src;
813 struct path_list *renames1, *renames2, *renames2Dst;
814 struct rename *ren1 = NULL, *ren2 = NULL;
815 const char *branch1, *branch2;
816 const char *ren1_src, *ren1_dst;
818 if (i >= a_renames->nr) {
819 compare = 1;
820 ren2 = b_renames->items[j++].util;
821 } else if (j >= b_renames->nr) {
822 compare = -1;
823 ren1 = a_renames->items[i++].util;
824 } else {
825 compare = strcmp(a_renames->items[i].path,
826 b_renames->items[j].path);
827 if (compare <= 0)
828 ren1 = a_renames->items[i++].util;
829 if (compare >= 0)
830 ren2 = b_renames->items[j++].util;
831 }
833 /* TODO: refactor, so that 1/2 are not needed */
834 if (ren1) {
835 renames1 = a_renames;
836 renames2 = b_renames;
837 renames2Dst = &b_by_dst;
838 branch1 = a_branch;
839 branch2 = b_branch;
840 } else {
841 struct rename *tmp;
842 renames1 = b_renames;
843 renames2 = a_renames;
844 renames2Dst = &a_by_dst;
845 branch1 = b_branch;
846 branch2 = a_branch;
847 tmp = ren2;
848 ren2 = ren1;
849 ren1 = tmp;
850 }
851 src = ren1->pair->one->path;
853 ren1->dst_entry->processed = 1;
854 ren1->src_entry->processed = 1;
856 if (ren1->processed)
857 continue;
858 ren1->processed = 1;
860 ren1_src = ren1->pair->one->path;
861 ren1_dst = ren1->pair->two->path;
863 if (ren2) {
864 const char *ren2_src = ren2->pair->one->path;
865 const char *ren2_dst = ren2->pair->two->path;
866 /* Renamed in 1 and renamed in 2 */
867 if (strcmp(ren1_src, ren2_src) != 0)
868 die("ren1.src != ren2.src");
869 ren2->dst_entry->processed = 1;
870 ren2->processed = 1;
871 if (strcmp(ren1_dst, ren2_dst) != 0) {
872 clean_merge = 0;
873 output(1, "CONFLICT (rename/rename): "
874 "Rename \"%s\"->\"%s\" in branch \"%s\" "
875 "rename \"%s\"->\"%s\" in \"%s\"%s",
876 src, ren1_dst, branch1,
877 src, ren2_dst, branch2,
878 index_only ? " (left unresolved)": "");
879 if (index_only) {
880 remove_file_from_cache(src);
881 update_file(0, ren1->pair->one->sha1,
882 ren1->pair->one->mode, src);
883 }
884 conflict_rename_rename(ren1, branch1, ren2, branch2);
885 } else {
886 struct merge_file_info mfi;
887 remove_file(1, ren1_src, 1);
888 mfi = merge_file(ren1->pair->one,
889 ren1->pair->two,
890 ren2->pair->two,
891 branch1,
892 branch2);
893 if (mfi.merge || !mfi.clean)
894 output(1, "Renamed %s->%s", src, ren1_dst);
896 if (mfi.merge)
897 output(2, "Auto-merged %s", ren1_dst);
899 if (!mfi.clean) {
900 output(1, "CONFLICT (content): merge conflict in %s",
901 ren1_dst);
902 clean_merge = 0;
904 if (!index_only)
905 update_stages(ren1_dst,
906 ren1->pair->one,
907 ren1->pair->two,
908 ren2->pair->two,
909 1 /* clear */);
910 }
911 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
912 }
913 } else {
914 /* Renamed in 1, maybe changed in 2 */
915 struct path_list_item *item;
916 /* we only use sha1 and mode of these */
917 struct diff_filespec src_other, dst_other;
918 int try_merge, stage = a_renames == renames1 ? 3: 2;
920 remove_file(1, ren1_src, index_only || stage == 3);
922 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
923 src_other.mode = ren1->src_entry->stages[stage].mode;
924 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
925 dst_other.mode = ren1->dst_entry->stages[stage].mode;
927 try_merge = 0;
929 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
930 clean_merge = 0;
931 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
932 " directory %s added in %s",
933 ren1_src, ren1_dst, branch1,
934 ren1_dst, branch2);
935 conflict_rename_dir(ren1, branch1);
936 } else if (sha_eq(src_other.sha1, null_sha1)) {
937 clean_merge = 0;
938 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
939 "and deleted in %s",
940 ren1_src, ren1_dst, branch1,
941 branch2);
942 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
943 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
944 const char *new_path;
945 clean_merge = 0;
946 try_merge = 1;
947 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
948 "%s added in %s",
949 ren1_src, ren1_dst, branch1,
950 ren1_dst, branch2);
951 new_path = unique_path(ren1_dst, branch2);
952 output(1, "Added as %s instead", new_path);
953 update_file(0, dst_other.sha1, dst_other.mode, new_path);
954 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
955 ren2 = item->util;
956 clean_merge = 0;
957 ren2->processed = 1;
958 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
959 "Renamed %s->%s in %s",
960 ren1_src, ren1_dst, branch1,
961 ren2->pair->one->path, ren2->pair->two->path, branch2);
962 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
963 } else
964 try_merge = 1;
966 if (try_merge) {
967 struct diff_filespec *o, *a, *b;
968 struct merge_file_info mfi;
969 src_other.path = (char *)ren1_src;
971 o = ren1->pair->one;
972 if (a_renames == renames1) {
973 a = ren1->pair->two;
974 b = &src_other;
975 } else {
976 b = ren1->pair->two;
977 a = &src_other;
978 }
979 mfi = merge_file(o, a, b,
980 a_branch, b_branch);
982 if (mfi.merge || !mfi.clean)
983 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
984 if (mfi.merge)
985 output(2, "Auto-merged %s", ren1_dst);
986 if (!mfi.clean) {
987 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
988 ren1_dst);
989 clean_merge = 0;
991 if (!index_only)
992 update_stages(ren1_dst,
993 o, a, b, 1);
994 }
995 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
996 }
997 }
998 }
999 path_list_clear(&a_by_dst, 0);
1000 path_list_clear(&b_by_dst, 0);
1002 return clean_merge;
1003 }
1005 static unsigned char *has_sha(const unsigned char *sha)
1006 {
1007 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
1008 }
1010 /* Per entry merge function */
1011 static int process_entry(const char *path, struct stage_data *entry,
1012 const char *branch1,
1013 const char *branch2)
1014 {
1015 /*
1016 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1017 print_index_entry("\tpath: ", entry);
1018 */
1019 int clean_merge = 1;
1020 unsigned char *o_sha = has_sha(entry->stages[1].sha);
1021 unsigned char *a_sha = has_sha(entry->stages[2].sha);
1022 unsigned char *b_sha = has_sha(entry->stages[3].sha);
1023 unsigned o_mode = entry->stages[1].mode;
1024 unsigned a_mode = entry->stages[2].mode;
1025 unsigned b_mode = entry->stages[3].mode;
1027 if (o_sha && (!a_sha || !b_sha)) {
1028 /* Case A: Deleted in one */
1029 if ((!a_sha && !b_sha) ||
1030 (sha_eq(a_sha, o_sha) && !b_sha) ||
1031 (!a_sha && sha_eq(b_sha, o_sha))) {
1032 /* Deleted in both or deleted in one and
1033 * unchanged in the other */
1034 if (a_sha)
1035 output(2, "Removed %s", path);
1036 /* do not touch working file if it did not exist */
1037 remove_file(1, path, !a_sha);
1038 } else {
1039 /* Deleted in one and changed in the other */
1040 clean_merge = 0;
1041 if (!a_sha) {
1042 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1043 "and modified in %s. Version %s of %s left in tree.",
1044 path, branch1,
1045 branch2, branch2, path);
1046 update_file(0, b_sha, b_mode, path);
1047 } else {
1048 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1049 "and modified in %s. Version %s of %s left in tree.",
1050 path, branch2,
1051 branch1, branch1, path);
1052 update_file(0, a_sha, a_mode, path);
1053 }
1054 }
1056 } else if ((!o_sha && a_sha && !b_sha) ||
1057 (!o_sha && !a_sha && b_sha)) {
1058 /* Case B: Added in one. */
1059 const char *add_branch;
1060 const char *other_branch;
1061 unsigned mode;
1062 const unsigned char *sha;
1063 const char *conf;
1065 if (a_sha) {
1066 add_branch = branch1;
1067 other_branch = branch2;
1068 mode = a_mode;
1069 sha = a_sha;
1070 conf = "file/directory";
1071 } else {
1072 add_branch = branch2;
1073 other_branch = branch1;
1074 mode = b_mode;
1075 sha = b_sha;
1076 conf = "directory/file";
1077 }
1078 if (path_list_has_path(¤t_directory_set, path)) {
1079 const char *new_path = unique_path(path, add_branch);
1080 clean_merge = 0;
1081 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1082 "Added %s as %s",
1083 conf, path, other_branch, path, new_path);
1084 remove_file(0, path, 0);
1085 update_file(0, sha, mode, new_path);
1086 } else {
1087 output(2, "Added %s", path);
1088 update_file(1, sha, mode, path);
1089 }
1090 } else if (a_sha && b_sha) {
1091 /* Case C: Added in both (check for same permissions) and */
1092 /* case D: Modified in both, but differently. */
1093 const char *reason = "content";
1094 struct merge_file_info mfi;
1095 struct diff_filespec o, a, b;
1097 if (!o_sha) {
1098 reason = "add/add";
1099 o_sha = (unsigned char *)null_sha1;
1100 }
1101 output(2, "Auto-merged %s", path);
1102 o.path = a.path = b.path = (char *)path;
1103 hashcpy(o.sha1, o_sha);
1104 o.mode = o_mode;
1105 hashcpy(a.sha1, a_sha);
1106 a.mode = a_mode;
1107 hashcpy(b.sha1, b_sha);
1108 b.mode = b_mode;
1110 mfi = merge_file(&o, &a, &b,
1111 branch1, branch2);
1113 if (mfi.clean)
1114 update_file(1, mfi.sha, mfi.mode, path);
1115 else {
1116 clean_merge = 0;
1117 output(1, "CONFLICT (%s): Merge conflict in %s",
1118 reason, path);
1120 if (index_only)
1121 update_file(0, mfi.sha, mfi.mode, path);
1122 else
1123 update_file_flags(mfi.sha, mfi.mode, path,
1124 0 /* update_cache */, 1 /* update_working_directory */);
1125 }
1126 } else
1127 die("Fatal merge failure, shouldn't happen.");
1129 return clean_merge;
1130 }
1132 static int merge_trees(struct tree *head,
1133 struct tree *merge,
1134 struct tree *common,
1135 const char *branch1,
1136 const char *branch2,
1137 struct tree **result)
1138 {
1139 int code, clean;
1140 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1141 output(0, "Already uptodate!");
1142 *result = head;
1143 return 1;
1144 }
1146 code = git_merge_trees(index_only, common, head, merge);
1148 if (code != 0)
1149 die("merging of trees %s and %s failed",
1150 sha1_to_hex(head->object.sha1),
1151 sha1_to_hex(merge->object.sha1));
1153 if (unmerged_index()) {
1154 struct path_list *entries, *re_head, *re_merge;
1155 int i;
1156 path_list_clear(¤t_file_set, 1);
1157 path_list_clear(¤t_directory_set, 1);
1158 get_files_dirs(head);
1159 get_files_dirs(merge);
1161 entries = get_unmerged();
1162 re_head = get_renames(head, common, head, merge, entries);
1163 re_merge = get_renames(merge, common, head, merge, entries);
1164 clean = process_renames(re_head, re_merge,
1165 branch1, branch2);
1166 total_cnt += entries->nr;
1167 for (i = 0; i < entries->nr; i++, merged_cnt++) {
1168 const char *path = entries->items[i].path;
1169 struct stage_data *e = entries->items[i].util;
1170 if (!e->processed
1171 && !process_entry(path, e, branch1, branch2))
1172 clean = 0;
1173 if (do_progress)
1174 display_progress();
1175 }
1177 path_list_clear(re_merge, 0);
1178 path_list_clear(re_head, 0);
1179 path_list_clear(entries, 1);
1181 }
1182 else
1183 clean = 1;
1185 if (index_only)
1186 *result = git_write_tree();
1188 return clean;
1189 }
1191 static struct commit_list *reverse_commit_list(struct commit_list *list)
1192 {
1193 struct commit_list *next = NULL, *current, *backup;
1194 for (current = list; current; current = backup) {
1195 backup = current->next;
1196 current->next = next;
1197 next = current;
1198 }
1199 return next;
1200 }
1202 /*
1203 * Merge the commits h1 and h2, return the resulting virtual
1204 * commit object and a flag indicating the cleanness of the merge.
1205 */
1206 static int merge(struct commit *h1,
1207 struct commit *h2,
1208 const char *branch1,
1209 const char *branch2,
1210 struct commit_list *ca,
1211 struct commit **result)
1212 {
1213 struct commit_list *iter;
1214 struct commit *merged_common_ancestors;
1215 struct tree *mrtree;
1216 int clean;
1218 if (show(4)) {
1219 output(4, "Merging:");
1220 output_commit_title(h1);
1221 output_commit_title(h2);
1222 }
1224 if (!ca) {
1225 ca = get_merge_bases(h1, h2, 1);
1226 ca = reverse_commit_list(ca);
1227 }
1229 if (show(5)) {
1230 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1231 for (iter = ca; iter; iter = iter->next)
1232 output_commit_title(iter->item);
1233 }
1235 merged_common_ancestors = pop_commit(&ca);
1236 if (merged_common_ancestors == NULL) {
1237 /* if there is no common ancestor, make an empty tree */
1238 struct tree *tree = xcalloc(1, sizeof(struct tree));
1240 tree->object.parsed = 1;
1241 tree->object.type = OBJ_TREE;
1242 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1243 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1244 }
1246 for (iter = ca; iter; iter = iter->next) {
1247 call_depth++;
1248 /*
1249 * When the merge fails, the result contains files
1250 * with conflict markers. The cleanness flag is
1251 * ignored, it was never actually used, as result of
1252 * merge_trees has always overwritten it: the committed
1253 * "conflicts" were already resolved.
1254 */
1255 discard_cache();
1256 merge(merged_common_ancestors, iter->item,
1257 "Temporary merge branch 1",
1258 "Temporary merge branch 2",
1259 NULL,
1260 &merged_common_ancestors);
1261 call_depth--;
1263 if (!merged_common_ancestors)
1264 die("merge returned no commit");
1265 }
1267 discard_cache();
1268 if (!call_depth) {
1269 read_cache();
1270 index_only = 0;
1271 } else
1272 index_only = 1;
1274 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1275 branch1, branch2, &mrtree);
1277 if (index_only) {
1278 *result = make_virtual_commit(mrtree, "merged tree");
1279 commit_list_insert(h1, &(*result)->parents);
1280 commit_list_insert(h2, &(*result)->parents->next);
1281 }
1282 if (!call_depth && do_progress) {
1283 /* Make sure we end at 100% */
1284 if (!total_cnt)
1285 total_cnt = 1;
1286 merged_cnt = total_cnt;
1287 progress_update = 1;
1288 display_progress();
1289 fputc('\n', stderr);
1290 }
1291 flush_output();
1292 return clean;
1293 }
1295 static const char *better_branch_name(const char *branch)
1296 {
1297 static char githead_env[8 + 40 + 1];
1298 char *name;
1300 if (strlen(branch) != 40)
1301 return branch;
1302 sprintf(githead_env, "GITHEAD_%s", branch);
1303 name = getenv(githead_env);
1304 return name ? name : branch;
1305 }
1307 static struct commit *get_ref(const char *ref)
1308 {
1309 unsigned char sha1[20];
1310 struct object *object;
1312 if (get_sha1(ref, sha1))
1313 die("Could not resolve ref '%s'", ref);
1314 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1315 if (object->type == OBJ_TREE)
1316 return make_virtual_commit((struct tree*)object,
1317 better_branch_name(ref));
1318 if (object->type != OBJ_COMMIT)
1319 return NULL;
1320 if (parse_commit((struct commit *)object))
1321 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1322 return (struct commit *)object;
1323 }
1325 static int merge_config(const char *var, const char *value)
1326 {
1327 if (!strcasecmp(var, "merge.verbosity")) {
1328 verbosity = git_config_int(var, value);
1329 return 0;
1330 }
1331 return git_default_config(var, value);
1332 }
1334 int main(int argc, char *argv[])
1335 {
1336 static const char *bases[20];
1337 static unsigned bases_count = 0;
1338 int i, clean;
1339 const char *branch1, *branch2;
1340 struct commit *result, *h1, *h2;
1341 struct commit_list *ca = NULL;
1342 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1343 int index_fd;
1345 git_config(merge_config);
1346 if (getenv("GIT_MERGE_VERBOSITY"))
1347 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1349 if (argc < 4)
1350 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1352 for (i = 1; i < argc; ++i) {
1353 if (!strcmp(argv[i], "--"))
1354 break;
1355 if (bases_count < sizeof(bases)/sizeof(*bases))
1356 bases[bases_count++] = argv[i];
1357 }
1358 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1359 die("Not handling anything other than two heads merge.");
1360 if (verbosity >= 5) {
1361 buffer_output = 0;
1362 do_progress = 0;
1363 }
1364 else
1365 do_progress = isatty(1);
1367 branch1 = argv[++i];
1368 branch2 = argv[++i];
1370 h1 = get_ref(branch1);
1371 h2 = get_ref(branch2);
1373 branch1 = better_branch_name(branch1);
1374 branch2 = better_branch_name(branch2);
1376 if (do_progress)
1377 setup_progress_signal();
1378 if (show(3))
1379 printf("Merging %s with %s\n", branch1, branch2);
1381 index_fd = hold_lock_file_for_update(lock, get_index_file(), 1);
1383 for (i = 0; i < bases_count; i++) {
1384 struct commit *ancestor = get_ref(bases[i]);
1385 ca = commit_list_insert(ancestor, &ca);
1386 }
1387 clean = merge(h1, h2, branch1, branch2, ca, &result);
1389 if (active_cache_changed &&
1390 (write_cache(index_fd, active_cache, active_nr) ||
1391 close(index_fd) || commit_lock_file(lock)))
1392 die ("unable to write %s", get_index_file());
1394 return clean ? 0: 1;
1395 }