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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 return NULL;
284 if (!active_cache_tree)
285 active_cache_tree = cache_tree();
287 if (!cache_tree_fully_valid(active_cache_tree) &&
288 cache_tree_update(active_cache_tree,
289 active_cache, active_nr, 0, 0) < 0)
290 die("error building trees");
292 result = lookup_tree(active_cache_tree->sha1);
294 return result;
295 }
297 static int save_files_dirs(const unsigned char *sha1,
298 const char *base, int baselen, const char *path,
299 unsigned int mode, int stage)
300 {
301 int len = strlen(path);
302 char *newpath = xmalloc(baselen + len + 1);
303 memcpy(newpath, base, baselen);
304 memcpy(newpath + baselen, path, len);
305 newpath[baselen + len] = '\0';
307 if (S_ISDIR(mode))
308 path_list_insert(newpath, ¤t_directory_set);
309 else
310 path_list_insert(newpath, ¤t_file_set);
311 free(newpath);
313 return READ_TREE_RECURSIVE;
314 }
316 static int get_files_dirs(struct tree *tree)
317 {
318 int n;
319 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
320 return 0;
321 n = current_file_set.nr + current_directory_set.nr;
322 return n;
323 }
325 /*
326 * Returns a index_entry instance which doesn't have to correspond to
327 * a real cache entry in Git's index.
328 */
329 static struct stage_data *insert_stage_data(const char *path,
330 struct tree *o, struct tree *a, struct tree *b,
331 struct path_list *entries)
332 {
333 struct path_list_item *item;
334 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
335 get_tree_entry(o->object.sha1, path,
336 e->stages[1].sha, &e->stages[1].mode);
337 get_tree_entry(a->object.sha1, path,
338 e->stages[2].sha, &e->stages[2].mode);
339 get_tree_entry(b->object.sha1, path,
340 e->stages[3].sha, &e->stages[3].mode);
341 item = path_list_insert(path, entries);
342 item->util = e;
343 return e;
344 }
346 /*
347 * Create a dictionary mapping file names to stage_data objects. The
348 * dictionary contains one entry for every path with a non-zero stage entry.
349 */
350 static struct path_list *get_unmerged(void)
351 {
352 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
353 int i;
355 unmerged->strdup_paths = 1;
356 total_cnt += active_nr;
358 for (i = 0; i < active_nr; i++, merged_cnt++) {
359 struct path_list_item *item;
360 struct stage_data *e;
361 struct cache_entry *ce = active_cache[i];
362 if (do_progress)
363 display_progress();
364 if (!ce_stage(ce))
365 continue;
367 item = path_list_lookup(ce->name, unmerged);
368 if (!item) {
369 item = path_list_insert(ce->name, unmerged);
370 item->util = xcalloc(1, sizeof(struct stage_data));
371 }
372 e = item->util;
373 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
374 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
375 }
377 return unmerged;
378 }
380 struct rename
381 {
382 struct diff_filepair *pair;
383 struct stage_data *src_entry;
384 struct stage_data *dst_entry;
385 unsigned processed:1;
386 };
388 /*
389 * Get information of all renames which occurred between 'o_tree' and
390 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
391 * 'b_tree') to be able to associate the correct cache entries with
392 * the rename information. 'tree' is always equal to either a_tree or b_tree.
393 */
394 static struct path_list *get_renames(struct tree *tree,
395 struct tree *o_tree,
396 struct tree *a_tree,
397 struct tree *b_tree,
398 struct path_list *entries)
399 {
400 int i;
401 struct path_list *renames;
402 struct diff_options opts;
404 renames = xcalloc(1, sizeof(struct path_list));
405 diff_setup(&opts);
406 opts.recursive = 1;
407 opts.detect_rename = DIFF_DETECT_RENAME;
408 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
409 if (diff_setup_done(&opts) < 0)
410 die("diff setup failed");
411 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
412 diffcore_std(&opts);
413 for (i = 0; i < diff_queued_diff.nr; ++i) {
414 struct path_list_item *item;
415 struct rename *re;
416 struct diff_filepair *pair = diff_queued_diff.queue[i];
417 if (pair->status != 'R') {
418 diff_free_filepair(pair);
419 continue;
420 }
421 re = xmalloc(sizeof(*re));
422 re->processed = 0;
423 re->pair = pair;
424 item = path_list_lookup(re->pair->one->path, entries);
425 if (!item)
426 re->src_entry = insert_stage_data(re->pair->one->path,
427 o_tree, a_tree, b_tree, entries);
428 else
429 re->src_entry = item->util;
431 item = path_list_lookup(re->pair->two->path, entries);
432 if (!item)
433 re->dst_entry = insert_stage_data(re->pair->two->path,
434 o_tree, a_tree, b_tree, entries);
435 else
436 re->dst_entry = item->util;
437 item = path_list_insert(pair->one->path, renames);
438 item->util = re;
439 }
440 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
441 diff_queued_diff.nr = 0;
442 diff_flush(&opts);
443 return renames;
444 }
446 static int update_stages(const char *path, struct diff_filespec *o,
447 struct diff_filespec *a, struct diff_filespec *b,
448 int clear)
449 {
450 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
451 if (clear)
452 if (remove_file_from_cache(path))
453 return -1;
454 if (o)
455 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
456 return -1;
457 if (a)
458 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
459 return -1;
460 if (b)
461 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
462 return -1;
463 return 0;
464 }
466 static int remove_path(const char *name)
467 {
468 int ret, len;
469 char *slash, *dirs;
471 ret = unlink(name);
472 if (ret)
473 return ret;
474 len = strlen(name);
475 dirs = xmalloc(len+1);
476 memcpy(dirs, name, len);
477 dirs[len] = '\0';
478 while ((slash = strrchr(name, '/'))) {
479 *slash = '\0';
480 len = slash - name;
481 if (rmdir(name) != 0)
482 break;
483 }
484 free(dirs);
485 return ret;
486 }
488 static int remove_file(int clean, const char *path, int no_wd)
489 {
490 int update_cache = index_only || clean;
491 int update_working_directory = !index_only && !no_wd;
493 if (update_cache) {
494 if (remove_file_from_cache(path))
495 return -1;
496 }
497 if (update_working_directory) {
498 unlink(path);
499 if (errno != ENOENT || errno != EISDIR)
500 return -1;
501 remove_path(path);
502 }
503 return 0;
504 }
506 static char *unique_path(const char *path, const char *branch)
507 {
508 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
509 int suffix = 0;
510 struct stat st;
511 char *p = newpath + strlen(path);
512 strcpy(newpath, path);
513 *(p++) = '~';
514 strcpy(p, branch);
515 for (; *p; ++p)
516 if ('/' == *p)
517 *p = '_';
518 while (path_list_has_path(¤t_file_set, newpath) ||
519 path_list_has_path(¤t_directory_set, newpath) ||
520 lstat(newpath, &st) == 0)
521 sprintf(p, "_%d", suffix++);
523 path_list_insert(newpath, ¤t_file_set);
524 return newpath;
525 }
527 static int mkdir_p(const char *path, unsigned long mode)
528 {
529 /* path points to cache entries, so xstrdup before messing with it */
530 char *buf = xstrdup(path);
531 int result = safe_create_leading_directories(buf);
532 free(buf);
533 return result;
534 }
536 static void flush_buffer(int fd, const char *buf, unsigned long size)
537 {
538 while (size > 0) {
539 long ret = write_in_full(fd, buf, size);
540 if (ret < 0) {
541 /* Ignore epipe */
542 if (errno == EPIPE)
543 break;
544 die("merge-recursive: %s", strerror(errno));
545 } else if (!ret) {
546 die("merge-recursive: disk full?");
547 }
548 size -= ret;
549 buf += ret;
550 }
551 }
553 static void update_file_flags(const unsigned char *sha,
554 unsigned mode,
555 const char *path,
556 int update_cache,
557 int update_wd)
558 {
559 if (index_only)
560 update_wd = 0;
562 if (update_wd) {
563 enum object_type type;
564 void *buf;
565 unsigned long size;
567 buf = read_sha1_file(sha, &type, &size);
568 if (!buf)
569 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
570 if (type != OBJ_BLOB)
571 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
573 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
574 int fd;
575 if (mkdir_p(path, 0777))
576 die("failed to create path %s: %s", path, strerror(errno));
577 unlink(path);
578 if (mode & 0100)
579 mode = 0777;
580 else
581 mode = 0666;
582 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
583 if (fd < 0)
584 die("failed to open %s: %s", path, strerror(errno));
585 flush_buffer(fd, buf, size);
586 close(fd);
587 } else if (S_ISLNK(mode)) {
588 char *lnk = xmalloc(size + 1);
589 memcpy(lnk, buf, size);
590 lnk[size] = '\0';
591 mkdir_p(path, 0777);
592 unlink(path);
593 symlink(lnk, path);
594 free(lnk);
595 } else
596 die("do not know what to do with %06o %s '%s'",
597 mode, sha1_to_hex(sha), path);
598 }
599 if (update_cache)
600 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
601 }
603 static void update_file(int clean,
604 const unsigned char *sha,
605 unsigned mode,
606 const char *path)
607 {
608 update_file_flags(sha, mode, path, index_only || clean, !index_only);
609 }
611 /* Low level file merging, update and removal */
613 struct merge_file_info
614 {
615 unsigned char sha[20];
616 unsigned mode;
617 unsigned clean:1,
618 merge:1;
619 };
621 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
622 {
623 unsigned long size;
624 enum object_type type;
626 if (!hashcmp(sha1, null_sha1)) {
627 mm->ptr = xstrdup("");
628 mm->size = 0;
629 return;
630 }
632 mm->ptr = read_sha1_file(sha1, &type, &size);
633 if (!mm->ptr || type != OBJ_BLOB)
634 die("unable to read blob object %s", sha1_to_hex(sha1));
635 mm->size = size;
636 }
638 static struct merge_file_info merge_file(struct diff_filespec *o,
639 struct diff_filespec *a, struct diff_filespec *b,
640 const char *branch1, const char *branch2)
641 {
642 struct merge_file_info result;
643 result.merge = 0;
644 result.clean = 1;
646 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
647 result.clean = 0;
648 if (S_ISREG(a->mode)) {
649 result.mode = a->mode;
650 hashcpy(result.sha, a->sha1);
651 } else {
652 result.mode = b->mode;
653 hashcpy(result.sha, b->sha1);
654 }
655 } else {
656 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
657 result.merge = 1;
659 result.mode = a->mode == o->mode ? b->mode: a->mode;
661 if (sha_eq(a->sha1, o->sha1))
662 hashcpy(result.sha, b->sha1);
663 else if (sha_eq(b->sha1, o->sha1))
664 hashcpy(result.sha, a->sha1);
665 else if (S_ISREG(a->mode)) {
666 mmfile_t orig, src1, src2;
667 mmbuffer_t result_buf;
668 xpparam_t xpp;
669 char *name1, *name2;
670 int merge_status;
672 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
673 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
675 fill_mm(o->sha1, &orig);
676 fill_mm(a->sha1, &src1);
677 fill_mm(b->sha1, &src2);
679 memset(&xpp, 0, sizeof(xpp));
680 merge_status = xdl_merge(&orig,
681 &src1, name1,
682 &src2, name2,
683 &xpp, XDL_MERGE_ZEALOUS,
684 &result_buf);
685 free(name1);
686 free(name2);
687 free(orig.ptr);
688 free(src1.ptr);
689 free(src2.ptr);
691 if ((merge_status < 0) || !result_buf.ptr)
692 die("Failed to execute internal merge");
694 if (write_sha1_file(result_buf.ptr, result_buf.size,
695 blob_type, result.sha))
696 die("Unable to add %s to database",
697 a->path);
699 free(result_buf.ptr);
700 result.clean = (merge_status == 0);
701 } else {
702 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
703 die("cannot merge modes?");
705 hashcpy(result.sha, a->sha1);
707 if (!sha_eq(a->sha1, b->sha1))
708 result.clean = 0;
709 }
710 }
712 return result;
713 }
715 static void conflict_rename_rename(struct rename *ren1,
716 const char *branch1,
717 struct rename *ren2,
718 const char *branch2)
719 {
720 char *del[2];
721 int delp = 0;
722 const char *ren1_dst = ren1->pair->two->path;
723 const char *ren2_dst = ren2->pair->two->path;
724 const char *dst_name1 = ren1_dst;
725 const char *dst_name2 = ren2_dst;
726 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
727 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
728 output(1, "%s is a directory in %s added as %s instead",
729 ren1_dst, branch2, dst_name1);
730 remove_file(0, ren1_dst, 0);
731 }
732 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
733 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
734 output(1, "%s is a directory in %s added as %s instead",
735 ren2_dst, branch1, dst_name2);
736 remove_file(0, ren2_dst, 0);
737 }
738 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
739 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
740 while (delp--)
741 free(del[delp]);
742 }
744 static void conflict_rename_dir(struct rename *ren1,
745 const char *branch1)
746 {
747 char *new_path = unique_path(ren1->pair->two->path, branch1);
748 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
749 remove_file(0, ren1->pair->two->path, 0);
750 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
751 free(new_path);
752 }
754 static void conflict_rename_rename_2(struct rename *ren1,
755 const char *branch1,
756 struct rename *ren2,
757 const char *branch2)
758 {
759 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
760 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
761 output(1, "Renamed %s to %s and %s to %s instead",
762 ren1->pair->one->path, new_path1,
763 ren2->pair->one->path, new_path2);
764 remove_file(0, ren1->pair->two->path, 0);
765 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
766 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
767 free(new_path2);
768 free(new_path1);
769 }
771 static int process_renames(struct path_list *a_renames,
772 struct path_list *b_renames,
773 const char *a_branch,
774 const char *b_branch)
775 {
776 int clean_merge = 1, i, j;
777 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
778 const struct rename *sre;
780 for (i = 0; i < a_renames->nr; i++) {
781 sre = a_renames->items[i].util;
782 path_list_insert(sre->pair->two->path, &a_by_dst)->util
783 = sre->dst_entry;
784 }
785 for (i = 0; i < b_renames->nr; i++) {
786 sre = b_renames->items[i].util;
787 path_list_insert(sre->pair->two->path, &b_by_dst)->util
788 = sre->dst_entry;
789 }
791 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
792 int compare;
793 char *src;
794 struct path_list *renames1, *renames2, *renames2Dst;
795 struct rename *ren1 = NULL, *ren2 = NULL;
796 const char *branch1, *branch2;
797 const char *ren1_src, *ren1_dst;
799 if (i >= a_renames->nr) {
800 compare = 1;
801 ren2 = b_renames->items[j++].util;
802 } else if (j >= b_renames->nr) {
803 compare = -1;
804 ren1 = a_renames->items[i++].util;
805 } else {
806 compare = strcmp(a_renames->items[i].path,
807 b_renames->items[j].path);
808 if (compare <= 0)
809 ren1 = a_renames->items[i++].util;
810 if (compare >= 0)
811 ren2 = b_renames->items[j++].util;
812 }
814 /* TODO: refactor, so that 1/2 are not needed */
815 if (ren1) {
816 renames1 = a_renames;
817 renames2 = b_renames;
818 renames2Dst = &b_by_dst;
819 branch1 = a_branch;
820 branch2 = b_branch;
821 } else {
822 struct rename *tmp;
823 renames1 = b_renames;
824 renames2 = a_renames;
825 renames2Dst = &a_by_dst;
826 branch1 = b_branch;
827 branch2 = a_branch;
828 tmp = ren2;
829 ren2 = ren1;
830 ren1 = tmp;
831 }
832 src = ren1->pair->one->path;
834 ren1->dst_entry->processed = 1;
835 ren1->src_entry->processed = 1;
837 if (ren1->processed)
838 continue;
839 ren1->processed = 1;
841 ren1_src = ren1->pair->one->path;
842 ren1_dst = ren1->pair->two->path;
844 if (ren2) {
845 const char *ren2_src = ren2->pair->one->path;
846 const char *ren2_dst = ren2->pair->two->path;
847 /* Renamed in 1 and renamed in 2 */
848 if (strcmp(ren1_src, ren2_src) != 0)
849 die("ren1.src != ren2.src");
850 ren2->dst_entry->processed = 1;
851 ren2->processed = 1;
852 if (strcmp(ren1_dst, ren2_dst) != 0) {
853 clean_merge = 0;
854 output(1, "CONFLICT (rename/rename): "
855 "Rename %s->%s in branch %s "
856 "rename %s->%s in %s",
857 src, ren1_dst, branch1,
858 src, ren2_dst, branch2);
859 conflict_rename_rename(ren1, branch1, ren2, branch2);
860 } else {
861 struct merge_file_info mfi;
862 remove_file(1, ren1_src, 1);
863 mfi = merge_file(ren1->pair->one,
864 ren1->pair->two,
865 ren2->pair->two,
866 branch1,
867 branch2);
868 if (mfi.merge || !mfi.clean)
869 output(1, "Renamed %s->%s", src, ren1_dst);
871 if (mfi.merge)
872 output(2, "Auto-merged %s", ren1_dst);
874 if (!mfi.clean) {
875 output(1, "CONFLICT (content): merge conflict in %s",
876 ren1_dst);
877 clean_merge = 0;
879 if (!index_only)
880 update_stages(ren1_dst,
881 ren1->pair->one,
882 ren1->pair->two,
883 ren2->pair->two,
884 1 /* clear */);
885 }
886 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
887 }
888 } else {
889 /* Renamed in 1, maybe changed in 2 */
890 struct path_list_item *item;
891 /* we only use sha1 and mode of these */
892 struct diff_filespec src_other, dst_other;
893 int try_merge, stage = a_renames == renames1 ? 3: 2;
895 remove_file(1, ren1_src, index_only || stage == 3);
897 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
898 src_other.mode = ren1->src_entry->stages[stage].mode;
899 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
900 dst_other.mode = ren1->dst_entry->stages[stage].mode;
902 try_merge = 0;
904 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
905 clean_merge = 0;
906 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
907 " directory %s added in %s",
908 ren1_src, ren1_dst, branch1,
909 ren1_dst, branch2);
910 conflict_rename_dir(ren1, branch1);
911 } else if (sha_eq(src_other.sha1, null_sha1)) {
912 clean_merge = 0;
913 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
914 "and deleted in %s",
915 ren1_src, ren1_dst, branch1,
916 branch2);
917 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
918 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
919 const char *new_path;
920 clean_merge = 0;
921 try_merge = 1;
922 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
923 "%s added in %s",
924 ren1_src, ren1_dst, branch1,
925 ren1_dst, branch2);
926 new_path = unique_path(ren1_dst, branch2);
927 output(1, "Added as %s instead", new_path);
928 update_file(0, dst_other.sha1, dst_other.mode, new_path);
929 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
930 ren2 = item->util;
931 clean_merge = 0;
932 ren2->processed = 1;
933 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
934 "Renamed %s->%s in %s",
935 ren1_src, ren1_dst, branch1,
936 ren2->pair->one->path, ren2->pair->two->path, branch2);
937 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
938 } else
939 try_merge = 1;
941 if (try_merge) {
942 struct diff_filespec *o, *a, *b;
943 struct merge_file_info mfi;
944 src_other.path = (char *)ren1_src;
946 o = ren1->pair->one;
947 if (a_renames == renames1) {
948 a = ren1->pair->two;
949 b = &src_other;
950 } else {
951 b = ren1->pair->two;
952 a = &src_other;
953 }
954 mfi = merge_file(o, a, b,
955 a_branch, b_branch);
957 if (mfi.merge || !mfi.clean)
958 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
959 if (mfi.merge)
960 output(2, "Auto-merged %s", ren1_dst);
961 if (!mfi.clean) {
962 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
963 ren1_dst);
964 clean_merge = 0;
966 if (!index_only)
967 update_stages(ren1_dst,
968 o, a, b, 1);
969 }
970 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
971 }
972 }
973 }
974 path_list_clear(&a_by_dst, 0);
975 path_list_clear(&b_by_dst, 0);
977 return clean_merge;
978 }
980 static unsigned char *has_sha(const unsigned char *sha)
981 {
982 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
983 }
985 /* Per entry merge function */
986 static int process_entry(const char *path, struct stage_data *entry,
987 const char *branch1,
988 const char *branch2)
989 {
990 /*
991 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
992 print_index_entry("\tpath: ", entry);
993 */
994 int clean_merge = 1;
995 unsigned char *o_sha = has_sha(entry->stages[1].sha);
996 unsigned char *a_sha = has_sha(entry->stages[2].sha);
997 unsigned char *b_sha = has_sha(entry->stages[3].sha);
998 unsigned o_mode = entry->stages[1].mode;
999 unsigned a_mode = entry->stages[2].mode;
1000 unsigned b_mode = entry->stages[3].mode;
1002 if (o_sha && (!a_sha || !b_sha)) {
1003 /* Case A: Deleted in one */
1004 if ((!a_sha && !b_sha) ||
1005 (sha_eq(a_sha, o_sha) && !b_sha) ||
1006 (!a_sha && sha_eq(b_sha, o_sha))) {
1007 /* Deleted in both or deleted in one and
1008 * unchanged in the other */
1009 if (a_sha)
1010 output(2, "Removed %s", path);
1011 /* do not touch working file if it did not exist */
1012 remove_file(1, path, !a_sha);
1013 } else {
1014 /* Deleted in one and changed in the other */
1015 clean_merge = 0;
1016 if (!a_sha) {
1017 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1018 "and modified in %s. Version %s of %s left in tree.",
1019 path, branch1,
1020 branch2, branch2, path);
1021 update_file(0, b_sha, b_mode, path);
1022 } else {
1023 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1024 "and modified in %s. Version %s of %s left in tree.",
1025 path, branch2,
1026 branch1, branch1, path);
1027 update_file(0, a_sha, a_mode, path);
1028 }
1029 }
1031 } else if ((!o_sha && a_sha && !b_sha) ||
1032 (!o_sha && !a_sha && b_sha)) {
1033 /* Case B: Added in one. */
1034 const char *add_branch;
1035 const char *other_branch;
1036 unsigned mode;
1037 const unsigned char *sha;
1038 const char *conf;
1040 if (a_sha) {
1041 add_branch = branch1;
1042 other_branch = branch2;
1043 mode = a_mode;
1044 sha = a_sha;
1045 conf = "file/directory";
1046 } else {
1047 add_branch = branch2;
1048 other_branch = branch1;
1049 mode = b_mode;
1050 sha = b_sha;
1051 conf = "directory/file";
1052 }
1053 if (path_list_has_path(¤t_directory_set, path)) {
1054 const char *new_path = unique_path(path, add_branch);
1055 clean_merge = 0;
1056 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1057 "Added %s as %s",
1058 conf, path, other_branch, path, new_path);
1059 remove_file(0, path, 0);
1060 update_file(0, sha, mode, new_path);
1061 } else {
1062 output(2, "Added %s", path);
1063 update_file(1, sha, mode, path);
1064 }
1065 } else if (a_sha && b_sha) {
1066 /* Case C: Added in both (check for same permissions) and */
1067 /* case D: Modified in both, but differently. */
1068 const char *reason = "content";
1069 struct merge_file_info mfi;
1070 struct diff_filespec o, a, b;
1072 if (!o_sha) {
1073 reason = "add/add";
1074 o_sha = (unsigned char *)null_sha1;
1075 }
1076 output(2, "Auto-merged %s", path);
1077 o.path = a.path = b.path = (char *)path;
1078 hashcpy(o.sha1, o_sha);
1079 o.mode = o_mode;
1080 hashcpy(a.sha1, a_sha);
1081 a.mode = a_mode;
1082 hashcpy(b.sha1, b_sha);
1083 b.mode = b_mode;
1085 mfi = merge_file(&o, &a, &b,
1086 branch1, branch2);
1088 if (mfi.clean)
1089 update_file(1, mfi.sha, mfi.mode, path);
1090 else {
1091 clean_merge = 0;
1092 output(1, "CONFLICT (%s): Merge conflict in %s",
1093 reason, path);
1095 if (index_only)
1096 update_file(0, mfi.sha, mfi.mode, path);
1097 else
1098 update_file_flags(mfi.sha, mfi.mode, path,
1099 0 /* update_cache */, 1 /* update_working_directory */);
1100 }
1101 } else
1102 die("Fatal merge failure, shouldn't happen.");
1104 return clean_merge;
1105 }
1107 static int merge_trees(struct tree *head,
1108 struct tree *merge,
1109 struct tree *common,
1110 const char *branch1,
1111 const char *branch2,
1112 struct tree **result)
1113 {
1114 int code, clean;
1115 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1116 output(0, "Already uptodate!");
1117 *result = head;
1118 return 1;
1119 }
1121 code = git_merge_trees(index_only, common, head, merge);
1123 if (code != 0)
1124 die("merging of trees %s and %s failed",
1125 sha1_to_hex(head->object.sha1),
1126 sha1_to_hex(merge->object.sha1));
1128 if (unmerged_index()) {
1129 struct path_list *entries, *re_head, *re_merge;
1130 int i;
1131 path_list_clear(¤t_file_set, 1);
1132 path_list_clear(¤t_directory_set, 1);
1133 get_files_dirs(head);
1134 get_files_dirs(merge);
1136 entries = get_unmerged();
1137 re_head = get_renames(head, common, head, merge, entries);
1138 re_merge = get_renames(merge, common, head, merge, entries);
1139 clean = process_renames(re_head, re_merge,
1140 branch1, branch2);
1141 total_cnt += entries->nr;
1142 for (i = 0; i < entries->nr; i++, merged_cnt++) {
1143 const char *path = entries->items[i].path;
1144 struct stage_data *e = entries->items[i].util;
1145 if (!e->processed
1146 && !process_entry(path, e, branch1, branch2))
1147 clean = 0;
1148 if (do_progress)
1149 display_progress();
1150 }
1152 path_list_clear(re_merge, 0);
1153 path_list_clear(re_head, 0);
1154 path_list_clear(entries, 1);
1156 }
1157 else
1158 clean = 1;
1160 if (index_only)
1161 *result = git_write_tree();
1163 return clean;
1164 }
1166 static struct commit_list *reverse_commit_list(struct commit_list *list)
1167 {
1168 struct commit_list *next = NULL, *current, *backup;
1169 for (current = list; current; current = backup) {
1170 backup = current->next;
1171 current->next = next;
1172 next = current;
1173 }
1174 return next;
1175 }
1177 /*
1178 * Merge the commits h1 and h2, return the resulting virtual
1179 * commit object and a flag indicating the cleanness of the merge.
1180 */
1181 static int merge(struct commit *h1,
1182 struct commit *h2,
1183 const char *branch1,
1184 const char *branch2,
1185 struct commit_list *ca,
1186 struct commit **result)
1187 {
1188 struct commit_list *iter;
1189 struct commit *merged_common_ancestors;
1190 struct tree *mrtree;
1191 int clean;
1193 if (show(4)) {
1194 output(4, "Merging:");
1195 output_commit_title(h1);
1196 output_commit_title(h2);
1197 }
1199 if (!ca) {
1200 ca = get_merge_bases(h1, h2, 1);
1201 ca = reverse_commit_list(ca);
1202 }
1204 if (show(5)) {
1205 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1206 for (iter = ca; iter; iter = iter->next)
1207 output_commit_title(iter->item);
1208 }
1210 merged_common_ancestors = pop_commit(&ca);
1211 if (merged_common_ancestors == NULL) {
1212 /* if there is no common ancestor, make an empty tree */
1213 struct tree *tree = xcalloc(1, sizeof(struct tree));
1215 tree->object.parsed = 1;
1216 tree->object.type = OBJ_TREE;
1217 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1218 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1219 }
1221 for (iter = ca; iter; iter = iter->next) {
1222 call_depth++;
1223 /*
1224 * When the merge fails, the result contains files
1225 * with conflict markers. The cleanness flag is
1226 * ignored, it was never actually used, as result of
1227 * merge_trees has always overwritten it: the committed
1228 * "conflicts" were already resolved.
1229 */
1230 discard_cache();
1231 merge(merged_common_ancestors, iter->item,
1232 "Temporary merge branch 1",
1233 "Temporary merge branch 2",
1234 NULL,
1235 &merged_common_ancestors);
1236 call_depth--;
1238 if (!merged_common_ancestors)
1239 die("merge returned no commit");
1240 }
1242 discard_cache();
1243 if (!call_depth) {
1244 read_cache();
1245 index_only = 0;
1246 } else
1247 index_only = 1;
1249 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1250 branch1, branch2, &mrtree);
1252 if (index_only) {
1253 *result = make_virtual_commit(mrtree, "merged tree");
1254 commit_list_insert(h1, &(*result)->parents);
1255 commit_list_insert(h2, &(*result)->parents->next);
1256 }
1257 if (!call_depth && do_progress) {
1258 /* Make sure we end at 100% */
1259 if (!total_cnt)
1260 total_cnt = 1;
1261 merged_cnt = total_cnt;
1262 progress_update = 1;
1263 display_progress();
1264 fputc('\n', stderr);
1265 }
1266 flush_output();
1267 return clean;
1268 }
1270 static const char *better_branch_name(const char *branch)
1271 {
1272 static char githead_env[8 + 40 + 1];
1273 char *name;
1275 if (strlen(branch) != 40)
1276 return branch;
1277 sprintf(githead_env, "GITHEAD_%s", branch);
1278 name = getenv(githead_env);
1279 return name ? name : branch;
1280 }
1282 static struct commit *get_ref(const char *ref)
1283 {
1284 unsigned char sha1[20];
1285 struct object *object;
1287 if (get_sha1(ref, sha1))
1288 die("Could not resolve ref '%s'", ref);
1289 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1290 if (object->type == OBJ_TREE)
1291 return make_virtual_commit((struct tree*)object,
1292 better_branch_name(ref));
1293 if (object->type != OBJ_COMMIT)
1294 return NULL;
1295 if (parse_commit((struct commit *)object))
1296 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1297 return (struct commit *)object;
1298 }
1300 static int merge_config(const char *var, const char *value)
1301 {
1302 if (!strcasecmp(var, "merge.verbosity")) {
1303 verbosity = git_config_int(var, value);
1304 return 0;
1305 }
1306 return git_default_config(var, value);
1307 }
1309 int main(int argc, char *argv[])
1310 {
1311 static const char *bases[20];
1312 static unsigned bases_count = 0;
1313 int i, clean;
1314 const char *branch1, *branch2;
1315 struct commit *result, *h1, *h2;
1316 struct commit_list *ca = NULL;
1317 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1318 int index_fd;
1320 git_config(merge_config);
1321 if (getenv("GIT_MERGE_VERBOSITY"))
1322 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1324 if (argc < 4)
1325 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1327 for (i = 1; i < argc; ++i) {
1328 if (!strcmp(argv[i], "--"))
1329 break;
1330 if (bases_count < sizeof(bases)/sizeof(*bases))
1331 bases[bases_count++] = argv[i];
1332 }
1333 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1334 die("Not handling anything other than two heads merge.");
1335 if (verbosity >= 5) {
1336 buffer_output = 0;
1337 do_progress = 0;
1338 }
1339 else
1340 do_progress = isatty(1);
1342 branch1 = argv[++i];
1343 branch2 = argv[++i];
1345 h1 = get_ref(branch1);
1346 h2 = get_ref(branch2);
1348 branch1 = better_branch_name(branch1);
1349 branch2 = better_branch_name(branch2);
1351 if (do_progress)
1352 setup_progress_signal();
1353 if (show(3))
1354 printf("Merging %s with %s\n", branch1, branch2);
1356 index_fd = hold_lock_file_for_update(lock, get_index_file(), 1);
1358 for (i = 0; i < bases_count; i++) {
1359 struct commit *ancestor = get_ref(bases[i]);
1360 ca = commit_list_insert(ancestor, &ca);
1361 }
1362 clean = merge(h1, h2, branch1, branch2, ca, &result);
1364 if (active_cache_changed &&
1365 (write_cache(index_fd, active_cache, active_nr) ||
1366 close(index_fd) || commit_lock_file(lock)))
1367 die ("unable to write %s", get_index_file());
1369 return clean ? 0: 1;
1370 }