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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 static int subtree_merge;
21 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
22 {
23 unsigned char shifted[20];
25 /*
26 * NEEDSWORK: this limits the recursion depth to hardcoded
27 * value '2' to avoid excessive overhead.
28 */
29 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
30 if (!hashcmp(two->object.sha1, shifted))
31 return two;
32 return lookup_tree(shifted);
33 }
35 /*
36 * A virtual commit has
37 * - (const char *)commit->util set to the name, and
38 * - *(int *)commit->object.sha1 set to the virtual id.
39 */
41 static unsigned commit_list_count(const struct commit_list *l)
42 {
43 unsigned c = 0;
44 for (; l; l = l->next )
45 c++;
46 return c;
47 }
49 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
50 {
51 struct commit *commit = xcalloc(1, sizeof(struct commit));
52 static unsigned virtual_id = 1;
53 commit->tree = tree;
54 commit->util = (void*)comment;
55 *(int*)commit->object.sha1 = virtual_id++;
56 /* avoid warnings */
57 commit->object.parsed = 1;
58 return commit;
59 }
61 /*
62 * Since we use get_tree_entry(), which does not put the read object into
63 * the object pool, we cannot rely on a == b.
64 */
65 static int sha_eq(const unsigned char *a, const unsigned char *b)
66 {
67 if (!a && !b)
68 return 2;
69 return a && b && hashcmp(a, b) == 0;
70 }
72 /*
73 * Since we want to write the index eventually, we cannot reuse the index
74 * for these (temporary) data.
75 */
76 struct stage_data
77 {
78 struct
79 {
80 unsigned mode;
81 unsigned char sha[20];
82 } stages[4];
83 unsigned processed:1;
84 };
86 struct output_buffer
87 {
88 struct output_buffer *next;
89 char *str;
90 };
92 static struct path_list current_file_set = {NULL, 0, 0, 1};
93 static struct path_list current_directory_set = {NULL, 0, 0, 1};
95 static int call_depth = 0;
96 static int verbosity = 2;
97 static int buffer_output = 1;
98 static int do_progress = 1;
99 static unsigned last_percent;
100 static unsigned merged_cnt;
101 static unsigned total_cnt;
102 static volatile sig_atomic_t progress_update;
103 static struct output_buffer *output_list, *output_end;
105 static int show (int v)
106 {
107 return (!call_depth && verbosity >= v) || verbosity >= 5;
108 }
110 static void output(int v, const char *fmt, ...)
111 {
112 va_list args;
113 va_start(args, fmt);
114 if (buffer_output && show(v)) {
115 struct output_buffer *b = xmalloc(sizeof(*b));
116 nfvasprintf(&b->str, fmt, args);
117 b->next = NULL;
118 if (output_end)
119 output_end->next = b;
120 else
121 output_list = b;
122 output_end = b;
123 } else if (show(v)) {
124 int i;
125 for (i = call_depth; i--;)
126 fputs(" ", stdout);
127 vfprintf(stdout, fmt, args);
128 fputc('\n', stdout);
129 }
130 va_end(args);
131 }
133 static void flush_output()
134 {
135 struct output_buffer *b, *n;
136 for (b = output_list; b; b = n) {
137 int i;
138 for (i = call_depth; i--;)
139 fputs(" ", stdout);
140 fputs(b->str, stdout);
141 fputc('\n', stdout);
142 n = b->next;
143 free(b->str);
144 free(b);
145 }
146 output_list = NULL;
147 output_end = NULL;
148 }
150 static void output_commit_title(struct commit *commit)
151 {
152 int i;
153 flush_output();
154 for (i = call_depth; i--;)
155 fputs(" ", stdout);
156 if (commit->util)
157 printf("virtual %s\n", (char *)commit->util);
158 else {
159 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
160 if (parse_commit(commit) != 0)
161 printf("(bad commit)\n");
162 else {
163 const char *s;
164 int len;
165 for (s = commit->buffer; *s; s++)
166 if (*s == '\n' && s[1] == '\n') {
167 s += 2;
168 break;
169 }
170 for (len = 0; s[len] && '\n' != s[len]; len++)
171 ; /* do nothing */
172 printf("%.*s\n", len, s);
173 }
174 }
175 }
177 static void progress_interval(int signum)
178 {
179 progress_update = 1;
180 }
182 static void setup_progress_signal(void)
183 {
184 struct sigaction sa;
185 struct itimerval v;
187 memset(&sa, 0, sizeof(sa));
188 sa.sa_handler = progress_interval;
189 sigemptyset(&sa.sa_mask);
190 sa.sa_flags = SA_RESTART;
191 sigaction(SIGALRM, &sa, NULL);
193 v.it_interval.tv_sec = 1;
194 v.it_interval.tv_usec = 0;
195 v.it_value = v.it_interval;
196 setitimer(ITIMER_REAL, &v, NULL);
197 }
199 static void display_progress()
200 {
201 unsigned percent = total_cnt ? merged_cnt * 100 / total_cnt : 0;
202 if (progress_update || percent != last_percent) {
203 fprintf(stderr, "%4u%% (%u/%u) done\r",
204 percent, merged_cnt, total_cnt);
205 progress_update = 0;
206 last_percent = percent;
207 }
208 }
210 static struct cache_entry *make_cache_entry(unsigned int mode,
211 const unsigned char *sha1, const char *path, int stage, int refresh)
212 {
213 int size, len;
214 struct cache_entry *ce;
216 if (!verify_path(path))
217 return NULL;
219 len = strlen(path);
220 size = cache_entry_size(len);
221 ce = xcalloc(1, size);
223 hashcpy(ce->sha1, sha1);
224 memcpy(ce->name, path, len);
225 ce->ce_flags = create_ce_flags(len, stage);
226 ce->ce_mode = create_ce_mode(mode);
228 if (refresh)
229 return refresh_cache_entry(ce, 0);
231 return ce;
232 }
234 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
235 const char *path, int stage, int refresh, int options)
236 {
237 struct cache_entry *ce;
238 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
239 if (!ce)
240 return error("addinfo_cache failed for path '%s'", path);
241 return add_cache_entry(ce, options);
242 }
244 /*
245 * This is a global variable which is used in a number of places but
246 * only written to in the 'merge' function.
247 *
248 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
249 * don't update the working directory.
250 * 0 => Leave unmerged entries in the cache and update
251 * the working directory.
252 */
253 static int index_only = 0;
255 static int git_merge_trees(int index_only,
256 struct tree *common,
257 struct tree *head,
258 struct tree *merge)
259 {
260 int rc;
261 struct object_list *trees = NULL;
262 struct unpack_trees_options opts;
264 memset(&opts, 0, sizeof(opts));
265 if (index_only)
266 opts.index_only = 1;
267 else
268 opts.update = 1;
269 opts.merge = 1;
270 opts.head_idx = 2;
271 opts.fn = threeway_merge;
273 object_list_append(&common->object, &trees);
274 object_list_append(&head->object, &trees);
275 object_list_append(&merge->object, &trees);
277 rc = unpack_trees(trees, &opts);
278 cache_tree_free(&active_cache_tree);
279 return rc;
280 }
282 static int unmerged_index(void)
283 {
284 int i;
285 for (i = 0; i < active_nr; i++) {
286 struct cache_entry *ce = active_cache[i];
287 if (ce_stage(ce))
288 return 1;
289 }
290 return 0;
291 }
293 static struct tree *git_write_tree(void)
294 {
295 struct tree *result = NULL;
297 if (unmerged_index()) {
298 int i;
299 output(0, "There are unmerged index entries:");
300 for (i = 0; i < active_nr; i++) {
301 struct cache_entry *ce = active_cache[i];
302 if (ce_stage(ce))
303 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
304 }
305 return NULL;
306 }
308 if (!active_cache_tree)
309 active_cache_tree = cache_tree();
311 if (!cache_tree_fully_valid(active_cache_tree) &&
312 cache_tree_update(active_cache_tree,
313 active_cache, active_nr, 0, 0) < 0)
314 die("error building trees");
316 result = lookup_tree(active_cache_tree->sha1);
318 return result;
319 }
321 static int save_files_dirs(const unsigned char *sha1,
322 const char *base, int baselen, const char *path,
323 unsigned int mode, int stage)
324 {
325 int len = strlen(path);
326 char *newpath = xmalloc(baselen + len + 1);
327 memcpy(newpath, base, baselen);
328 memcpy(newpath + baselen, path, len);
329 newpath[baselen + len] = '\0';
331 if (S_ISDIR(mode))
332 path_list_insert(newpath, ¤t_directory_set);
333 else
334 path_list_insert(newpath, ¤t_file_set);
335 free(newpath);
337 return READ_TREE_RECURSIVE;
338 }
340 static int get_files_dirs(struct tree *tree)
341 {
342 int n;
343 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
344 return 0;
345 n = current_file_set.nr + current_directory_set.nr;
346 return n;
347 }
349 /*
350 * Returns a index_entry instance which doesn't have to correspond to
351 * a real cache entry in Git's index.
352 */
353 static struct stage_data *insert_stage_data(const char *path,
354 struct tree *o, struct tree *a, struct tree *b,
355 struct path_list *entries)
356 {
357 struct path_list_item *item;
358 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
359 get_tree_entry(o->object.sha1, path,
360 e->stages[1].sha, &e->stages[1].mode);
361 get_tree_entry(a->object.sha1, path,
362 e->stages[2].sha, &e->stages[2].mode);
363 get_tree_entry(b->object.sha1, path,
364 e->stages[3].sha, &e->stages[3].mode);
365 item = path_list_insert(path, entries);
366 item->util = e;
367 return e;
368 }
370 /*
371 * Create a dictionary mapping file names to stage_data objects. The
372 * dictionary contains one entry for every path with a non-zero stage entry.
373 */
374 static struct path_list *get_unmerged(void)
375 {
376 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
377 int i;
379 unmerged->strdup_paths = 1;
380 total_cnt += active_nr;
382 for (i = 0; i < active_nr; i++, merged_cnt++) {
383 struct path_list_item *item;
384 struct stage_data *e;
385 struct cache_entry *ce = active_cache[i];
386 if (do_progress)
387 display_progress();
388 if (!ce_stage(ce))
389 continue;
391 item = path_list_lookup(ce->name, unmerged);
392 if (!item) {
393 item = path_list_insert(ce->name, unmerged);
394 item->util = xcalloc(1, sizeof(struct stage_data));
395 }
396 e = item->util;
397 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
398 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
399 }
401 return unmerged;
402 }
404 struct rename
405 {
406 struct diff_filepair *pair;
407 struct stage_data *src_entry;
408 struct stage_data *dst_entry;
409 unsigned processed:1;
410 };
412 /*
413 * Get information of all renames which occurred between 'o_tree' and
414 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
415 * 'b_tree') to be able to associate the correct cache entries with
416 * the rename information. 'tree' is always equal to either a_tree or b_tree.
417 */
418 static struct path_list *get_renames(struct tree *tree,
419 struct tree *o_tree,
420 struct tree *a_tree,
421 struct tree *b_tree,
422 struct path_list *entries)
423 {
424 int i;
425 struct path_list *renames;
426 struct diff_options opts;
428 renames = xcalloc(1, sizeof(struct path_list));
429 diff_setup(&opts);
430 opts.recursive = 1;
431 opts.detect_rename = DIFF_DETECT_RENAME;
432 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
433 if (diff_setup_done(&opts) < 0)
434 die("diff setup failed");
435 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
436 diffcore_std(&opts);
437 for (i = 0; i < diff_queued_diff.nr; ++i) {
438 struct path_list_item *item;
439 struct rename *re;
440 struct diff_filepair *pair = diff_queued_diff.queue[i];
441 if (pair->status != 'R') {
442 diff_free_filepair(pair);
443 continue;
444 }
445 re = xmalloc(sizeof(*re));
446 re->processed = 0;
447 re->pair = pair;
448 item = path_list_lookup(re->pair->one->path, entries);
449 if (!item)
450 re->src_entry = insert_stage_data(re->pair->one->path,
451 o_tree, a_tree, b_tree, entries);
452 else
453 re->src_entry = item->util;
455 item = path_list_lookup(re->pair->two->path, entries);
456 if (!item)
457 re->dst_entry = insert_stage_data(re->pair->two->path,
458 o_tree, a_tree, b_tree, entries);
459 else
460 re->dst_entry = item->util;
461 item = path_list_insert(pair->one->path, renames);
462 item->util = re;
463 }
464 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
465 diff_queued_diff.nr = 0;
466 diff_flush(&opts);
467 return renames;
468 }
470 static int update_stages(const char *path, struct diff_filespec *o,
471 struct diff_filespec *a, struct diff_filespec *b,
472 int clear)
473 {
474 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
475 if (clear)
476 if (remove_file_from_cache(path))
477 return -1;
478 if (o)
479 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
480 return -1;
481 if (a)
482 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
483 return -1;
484 if (b)
485 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
486 return -1;
487 return 0;
488 }
490 static int remove_path(const char *name)
491 {
492 int ret, len;
493 char *slash, *dirs;
495 ret = unlink(name);
496 if (ret)
497 return ret;
498 len = strlen(name);
499 dirs = xmalloc(len+1);
500 memcpy(dirs, name, len);
501 dirs[len] = '\0';
502 while ((slash = strrchr(name, '/'))) {
503 *slash = '\0';
504 len = slash - name;
505 if (rmdir(name) != 0)
506 break;
507 }
508 free(dirs);
509 return ret;
510 }
512 static int remove_file(int clean, const char *path, int no_wd)
513 {
514 int update_cache = index_only || clean;
515 int update_working_directory = !index_only && !no_wd;
517 if (update_cache) {
518 if (remove_file_from_cache(path))
519 return -1;
520 }
521 if (update_working_directory) {
522 unlink(path);
523 if (errno != ENOENT || errno != EISDIR)
524 return -1;
525 remove_path(path);
526 }
527 return 0;
528 }
530 static char *unique_path(const char *path, const char *branch)
531 {
532 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
533 int suffix = 0;
534 struct stat st;
535 char *p = newpath + strlen(path);
536 strcpy(newpath, path);
537 *(p++) = '~';
538 strcpy(p, branch);
539 for (; *p; ++p)
540 if ('/' == *p)
541 *p = '_';
542 while (path_list_has_path(¤t_file_set, newpath) ||
543 path_list_has_path(¤t_directory_set, newpath) ||
544 lstat(newpath, &st) == 0)
545 sprintf(p, "_%d", suffix++);
547 path_list_insert(newpath, ¤t_file_set);
548 return newpath;
549 }
551 static int mkdir_p(const char *path, unsigned long mode)
552 {
553 /* path points to cache entries, so xstrdup before messing with it */
554 char *buf = xstrdup(path);
555 int result = safe_create_leading_directories(buf);
556 free(buf);
557 return result;
558 }
560 static void flush_buffer(int fd, const char *buf, unsigned long size)
561 {
562 while (size > 0) {
563 long ret = write_in_full(fd, buf, size);
564 if (ret < 0) {
565 /* Ignore epipe */
566 if (errno == EPIPE)
567 break;
568 die("merge-recursive: %s", strerror(errno));
569 } else if (!ret) {
570 die("merge-recursive: disk full?");
571 }
572 size -= ret;
573 buf += ret;
574 }
575 }
577 static void update_file_flags(const unsigned char *sha,
578 unsigned mode,
579 const char *path,
580 int update_cache,
581 int update_wd)
582 {
583 if (index_only)
584 update_wd = 0;
586 if (update_wd) {
587 enum object_type type;
588 void *buf;
589 unsigned long size;
591 buf = read_sha1_file(sha, &type, &size);
592 if (!buf)
593 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
594 if (type != OBJ_BLOB)
595 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
597 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
598 int fd;
599 int status;
600 const char *msg = "failed to create path '%s'%s";
602 status = mkdir_p(path, 0777);
603 if (status) {
604 if (status == -3) {
605 /* something else exists */
606 error(msg, path, ": perhaps a D/F conflict?");
607 update_wd = 0;
608 goto update_index;
609 }
610 die(msg, path, "");
611 }
612 if (unlink(path)) {
613 if (errno == EISDIR) {
614 /* something else exists */
615 error(msg, path, ": perhaps a D/F conflict?");
616 update_wd = 0;
617 goto update_index;
618 }
619 if (errno != ENOENT)
620 die("failed to unlink %s "
621 "in preparation to update: %s",
622 path, strerror(errno));
623 }
624 if (mode & 0100)
625 mode = 0777;
626 else
627 mode = 0666;
628 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
629 if (fd < 0)
630 die("failed to open %s: %s", path, strerror(errno));
631 flush_buffer(fd, buf, size);
632 close(fd);
633 } else if (S_ISLNK(mode)) {
634 char *lnk = xmalloc(size + 1);
635 memcpy(lnk, buf, size);
636 lnk[size] = '\0';
637 mkdir_p(path, 0777);
638 unlink(path);
639 symlink(lnk, path);
640 free(lnk);
641 } else
642 die("do not know what to do with %06o %s '%s'",
643 mode, sha1_to_hex(sha), path);
644 }
645 update_index:
646 if (update_cache)
647 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
648 }
650 static void update_file(int clean,
651 const unsigned char *sha,
652 unsigned mode,
653 const char *path)
654 {
655 update_file_flags(sha, mode, path, index_only || clean, !index_only);
656 }
658 /* Low level file merging, update and removal */
660 struct merge_file_info
661 {
662 unsigned char sha[20];
663 unsigned mode;
664 unsigned clean:1,
665 merge:1;
666 };
668 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
669 {
670 unsigned long size;
671 enum object_type type;
673 if (!hashcmp(sha1, null_sha1)) {
674 mm->ptr = xstrdup("");
675 mm->size = 0;
676 return;
677 }
679 mm->ptr = read_sha1_file(sha1, &type, &size);
680 if (!mm->ptr || type != OBJ_BLOB)
681 die("unable to read blob object %s", sha1_to_hex(sha1));
682 mm->size = size;
683 }
685 static struct merge_file_info merge_file(struct diff_filespec *o,
686 struct diff_filespec *a, struct diff_filespec *b,
687 const char *branch1, const char *branch2)
688 {
689 struct merge_file_info result;
690 result.merge = 0;
691 result.clean = 1;
693 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
694 result.clean = 0;
695 if (S_ISREG(a->mode)) {
696 result.mode = a->mode;
697 hashcpy(result.sha, a->sha1);
698 } else {
699 result.mode = b->mode;
700 hashcpy(result.sha, b->sha1);
701 }
702 } else {
703 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
704 result.merge = 1;
706 result.mode = a->mode == o->mode ? b->mode: a->mode;
708 if (sha_eq(a->sha1, o->sha1))
709 hashcpy(result.sha, b->sha1);
710 else if (sha_eq(b->sha1, o->sha1))
711 hashcpy(result.sha, a->sha1);
712 else if (S_ISREG(a->mode)) {
713 mmfile_t orig, src1, src2;
714 mmbuffer_t result_buf;
715 xpparam_t xpp;
716 char *name1, *name2;
717 int merge_status;
719 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
720 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
722 fill_mm(o->sha1, &orig);
723 fill_mm(a->sha1, &src1);
724 fill_mm(b->sha1, &src2);
726 memset(&xpp, 0, sizeof(xpp));
727 merge_status = xdl_merge(&orig,
728 &src1, name1,
729 &src2, name2,
730 &xpp, XDL_MERGE_ZEALOUS,
731 &result_buf);
732 free(name1);
733 free(name2);
734 free(orig.ptr);
735 free(src1.ptr);
736 free(src2.ptr);
738 if ((merge_status < 0) || !result_buf.ptr)
739 die("Failed to execute internal merge");
741 if (write_sha1_file(result_buf.ptr, result_buf.size,
742 blob_type, result.sha))
743 die("Unable to add %s to database",
744 a->path);
746 free(result_buf.ptr);
747 result.clean = (merge_status == 0);
748 } else {
749 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
750 die("cannot merge modes?");
752 hashcpy(result.sha, a->sha1);
754 if (!sha_eq(a->sha1, b->sha1))
755 result.clean = 0;
756 }
757 }
759 return result;
760 }
762 static void conflict_rename_rename(struct rename *ren1,
763 const char *branch1,
764 struct rename *ren2,
765 const char *branch2)
766 {
767 char *del[2];
768 int delp = 0;
769 const char *ren1_dst = ren1->pair->two->path;
770 const char *ren2_dst = ren2->pair->two->path;
771 const char *dst_name1 = ren1_dst;
772 const char *dst_name2 = ren2_dst;
773 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
774 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
775 output(1, "%s is a directory in %s added as %s instead",
776 ren1_dst, branch2, dst_name1);
777 remove_file(0, ren1_dst, 0);
778 }
779 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
780 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
781 output(1, "%s is a directory in %s added as %s instead",
782 ren2_dst, branch1, dst_name2);
783 remove_file(0, ren2_dst, 0);
784 }
785 if (index_only) {
786 remove_file_from_cache(dst_name1);
787 remove_file_from_cache(dst_name2);
788 /*
789 * Uncomment to leave the conflicting names in the resulting tree
790 *
791 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
792 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
793 */
794 } else {
795 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
796 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
797 }
798 while (delp--)
799 free(del[delp]);
800 }
802 static void conflict_rename_dir(struct rename *ren1,
803 const char *branch1)
804 {
805 char *new_path = unique_path(ren1->pair->two->path, branch1);
806 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
807 remove_file(0, ren1->pair->two->path, 0);
808 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
809 free(new_path);
810 }
812 static void conflict_rename_rename_2(struct rename *ren1,
813 const char *branch1,
814 struct rename *ren2,
815 const char *branch2)
816 {
817 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
818 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
819 output(1, "Renamed %s to %s and %s to %s instead",
820 ren1->pair->one->path, new_path1,
821 ren2->pair->one->path, new_path2);
822 remove_file(0, ren1->pair->two->path, 0);
823 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
824 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
825 free(new_path2);
826 free(new_path1);
827 }
829 static int process_renames(struct path_list *a_renames,
830 struct path_list *b_renames,
831 const char *a_branch,
832 const char *b_branch)
833 {
834 int clean_merge = 1, i, j;
835 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
836 const struct rename *sre;
838 for (i = 0; i < a_renames->nr; i++) {
839 sre = a_renames->items[i].util;
840 path_list_insert(sre->pair->two->path, &a_by_dst)->util
841 = sre->dst_entry;
842 }
843 for (i = 0; i < b_renames->nr; i++) {
844 sre = b_renames->items[i].util;
845 path_list_insert(sre->pair->two->path, &b_by_dst)->util
846 = sre->dst_entry;
847 }
849 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
850 int compare;
851 char *src;
852 struct path_list *renames1, *renames2, *renames2Dst;
853 struct rename *ren1 = NULL, *ren2 = NULL;
854 const char *branch1, *branch2;
855 const char *ren1_src, *ren1_dst;
857 if (i >= a_renames->nr) {
858 compare = 1;
859 ren2 = b_renames->items[j++].util;
860 } else if (j >= b_renames->nr) {
861 compare = -1;
862 ren1 = a_renames->items[i++].util;
863 } else {
864 compare = strcmp(a_renames->items[i].path,
865 b_renames->items[j].path);
866 if (compare <= 0)
867 ren1 = a_renames->items[i++].util;
868 if (compare >= 0)
869 ren2 = b_renames->items[j++].util;
870 }
872 /* TODO: refactor, so that 1/2 are not needed */
873 if (ren1) {
874 renames1 = a_renames;
875 renames2 = b_renames;
876 renames2Dst = &b_by_dst;
877 branch1 = a_branch;
878 branch2 = b_branch;
879 } else {
880 struct rename *tmp;
881 renames1 = b_renames;
882 renames2 = a_renames;
883 renames2Dst = &a_by_dst;
884 branch1 = b_branch;
885 branch2 = a_branch;
886 tmp = ren2;
887 ren2 = ren1;
888 ren1 = tmp;
889 }
890 src = ren1->pair->one->path;
892 ren1->dst_entry->processed = 1;
893 ren1->src_entry->processed = 1;
895 if (ren1->processed)
896 continue;
897 ren1->processed = 1;
899 ren1_src = ren1->pair->one->path;
900 ren1_dst = ren1->pair->two->path;
902 if (ren2) {
903 const char *ren2_src = ren2->pair->one->path;
904 const char *ren2_dst = ren2->pair->two->path;
905 /* Renamed in 1 and renamed in 2 */
906 if (strcmp(ren1_src, ren2_src) != 0)
907 die("ren1.src != ren2.src");
908 ren2->dst_entry->processed = 1;
909 ren2->processed = 1;
910 if (strcmp(ren1_dst, ren2_dst) != 0) {
911 clean_merge = 0;
912 output(1, "CONFLICT (rename/rename): "
913 "Rename \"%s\"->\"%s\" in branch \"%s\" "
914 "rename \"%s\"->\"%s\" in \"%s\"%s",
915 src, ren1_dst, branch1,
916 src, ren2_dst, branch2,
917 index_only ? " (left unresolved)": "");
918 if (index_only) {
919 remove_file_from_cache(src);
920 update_file(0, ren1->pair->one->sha1,
921 ren1->pair->one->mode, src);
922 }
923 conflict_rename_rename(ren1, branch1, ren2, branch2);
924 } else {
925 struct merge_file_info mfi;
926 remove_file(1, ren1_src, 1);
927 mfi = merge_file(ren1->pair->one,
928 ren1->pair->two,
929 ren2->pair->two,
930 branch1,
931 branch2);
932 if (mfi.merge || !mfi.clean)
933 output(1, "Renamed %s->%s", src, ren1_dst);
935 if (mfi.merge)
936 output(2, "Auto-merged %s", ren1_dst);
938 if (!mfi.clean) {
939 output(1, "CONFLICT (content): merge conflict in %s",
940 ren1_dst);
941 clean_merge = 0;
943 if (!index_only)
944 update_stages(ren1_dst,
945 ren1->pair->one,
946 ren1->pair->two,
947 ren2->pair->two,
948 1 /* clear */);
949 }
950 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
951 }
952 } else {
953 /* Renamed in 1, maybe changed in 2 */
954 struct path_list_item *item;
955 /* we only use sha1 and mode of these */
956 struct diff_filespec src_other, dst_other;
957 int try_merge, stage = a_renames == renames1 ? 3: 2;
959 remove_file(1, ren1_src, index_only || stage == 3);
961 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
962 src_other.mode = ren1->src_entry->stages[stage].mode;
963 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
964 dst_other.mode = ren1->dst_entry->stages[stage].mode;
966 try_merge = 0;
968 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
969 clean_merge = 0;
970 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
971 " directory %s added in %s",
972 ren1_src, ren1_dst, branch1,
973 ren1_dst, branch2);
974 conflict_rename_dir(ren1, branch1);
975 } else if (sha_eq(src_other.sha1, null_sha1)) {
976 clean_merge = 0;
977 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
978 "and deleted in %s",
979 ren1_src, ren1_dst, branch1,
980 branch2);
981 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
982 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
983 const char *new_path;
984 clean_merge = 0;
985 try_merge = 1;
986 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
987 "%s added in %s",
988 ren1_src, ren1_dst, branch1,
989 ren1_dst, branch2);
990 new_path = unique_path(ren1_dst, branch2);
991 output(1, "Added as %s instead", new_path);
992 update_file(0, dst_other.sha1, dst_other.mode, new_path);
993 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
994 ren2 = item->util;
995 clean_merge = 0;
996 ren2->processed = 1;
997 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
998 "Renamed %s->%s in %s",
999 ren1_src, ren1_dst, branch1,
1000 ren2->pair->one->path, ren2->pair->two->path, branch2);
1001 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
1002 } else
1003 try_merge = 1;
1005 if (try_merge) {
1006 struct diff_filespec *o, *a, *b;
1007 struct merge_file_info mfi;
1008 src_other.path = (char *)ren1_src;
1010 o = ren1->pair->one;
1011 if (a_renames == renames1) {
1012 a = ren1->pair->two;
1013 b = &src_other;
1014 } else {
1015 b = ren1->pair->two;
1016 a = &src_other;
1017 }
1018 mfi = merge_file(o, a, b,
1019 a_branch, b_branch);
1021 if (mfi.merge || !mfi.clean)
1022 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
1023 if (mfi.merge)
1024 output(2, "Auto-merged %s", ren1_dst);
1025 if (!mfi.clean) {
1026 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
1027 ren1_dst);
1028 clean_merge = 0;
1030 if (!index_only)
1031 update_stages(ren1_dst,
1032 o, a, b, 1);
1033 }
1034 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1035 }
1036 }
1037 }
1038 path_list_clear(&a_by_dst, 0);
1039 path_list_clear(&b_by_dst, 0);
1041 return clean_merge;
1042 }
1044 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1045 {
1046 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1047 }
1049 /* Per entry merge function */
1050 static int process_entry(const char *path, struct stage_data *entry,
1051 const char *branch1,
1052 const char *branch2)
1053 {
1054 /*
1055 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1056 print_index_entry("\tpath: ", entry);
1057 */
1058 int clean_merge = 1;
1059 unsigned o_mode = entry->stages[1].mode;
1060 unsigned a_mode = entry->stages[2].mode;
1061 unsigned b_mode = entry->stages[3].mode;
1062 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1063 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1064 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1066 if (o_sha && (!a_sha || !b_sha)) {
1067 /* Case A: Deleted in one */
1068 if ((!a_sha && !b_sha) ||
1069 (sha_eq(a_sha, o_sha) && !b_sha) ||
1070 (!a_sha && sha_eq(b_sha, o_sha))) {
1071 /* Deleted in both or deleted in one and
1072 * unchanged in the other */
1073 if (a_sha)
1074 output(2, "Removed %s", path);
1075 /* do not touch working file if it did not exist */
1076 remove_file(1, path, !a_sha);
1077 } else {
1078 /* Deleted in one and changed in the other */
1079 clean_merge = 0;
1080 if (!a_sha) {
1081 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1082 "and modified in %s. Version %s of %s left in tree.",
1083 path, branch1,
1084 branch2, branch2, path);
1085 update_file(0, b_sha, b_mode, path);
1086 } else {
1087 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1088 "and modified in %s. Version %s of %s left in tree.",
1089 path, branch2,
1090 branch1, branch1, path);
1091 update_file(0, a_sha, a_mode, path);
1092 }
1093 }
1095 } else if ((!o_sha && a_sha && !b_sha) ||
1096 (!o_sha && !a_sha && b_sha)) {
1097 /* Case B: Added in one. */
1098 const char *add_branch;
1099 const char *other_branch;
1100 unsigned mode;
1101 const unsigned char *sha;
1102 const char *conf;
1104 if (a_sha) {
1105 add_branch = branch1;
1106 other_branch = branch2;
1107 mode = a_mode;
1108 sha = a_sha;
1109 conf = "file/directory";
1110 } else {
1111 add_branch = branch2;
1112 other_branch = branch1;
1113 mode = b_mode;
1114 sha = b_sha;
1115 conf = "directory/file";
1116 }
1117 if (path_list_has_path(¤t_directory_set, path)) {
1118 const char *new_path = unique_path(path, add_branch);
1119 clean_merge = 0;
1120 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1121 "Added %s as %s",
1122 conf, path, other_branch, path, new_path);
1123 remove_file(0, path, 0);
1124 update_file(0, sha, mode, new_path);
1125 } else {
1126 output(2, "Added %s", path);
1127 update_file(1, sha, mode, path);
1128 }
1129 } else if (a_sha && b_sha) {
1130 /* Case C: Added in both (check for same permissions) and */
1131 /* case D: Modified in both, but differently. */
1132 const char *reason = "content";
1133 struct merge_file_info mfi;
1134 struct diff_filespec o, a, b;
1136 if (!o_sha) {
1137 reason = "add/add";
1138 o_sha = (unsigned char *)null_sha1;
1139 }
1140 output(2, "Auto-merged %s", path);
1141 o.path = a.path = b.path = (char *)path;
1142 hashcpy(o.sha1, o_sha);
1143 o.mode = o_mode;
1144 hashcpy(a.sha1, a_sha);
1145 a.mode = a_mode;
1146 hashcpy(b.sha1, b_sha);
1147 b.mode = b_mode;
1149 mfi = merge_file(&o, &a, &b,
1150 branch1, branch2);
1152 if (mfi.clean)
1153 update_file(1, mfi.sha, mfi.mode, path);
1154 else {
1155 clean_merge = 0;
1156 output(1, "CONFLICT (%s): Merge conflict in %s",
1157 reason, path);
1159 if (index_only)
1160 update_file(0, mfi.sha, mfi.mode, path);
1161 else
1162 update_file_flags(mfi.sha, mfi.mode, path,
1163 0 /* update_cache */, 1 /* update_working_directory */);
1164 }
1165 } else if (!o_sha && !a_sha && !b_sha) {
1166 /*
1167 * this entry was deleted altogether. a_mode == 0 means
1168 * we had that path and want to actively remove it.
1169 */
1170 remove_file(1, path, !a_mode);
1171 } else
1172 die("Fatal merge failure, shouldn't happen.");
1174 return clean_merge;
1175 }
1177 static int merge_trees(struct tree *head,
1178 struct tree *merge,
1179 struct tree *common,
1180 const char *branch1,
1181 const char *branch2,
1182 struct tree **result)
1183 {
1184 int code, clean;
1186 if (subtree_merge) {
1187 merge = shift_tree_object(head, merge);
1188 common = shift_tree_object(head, common);
1189 }
1191 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1192 output(0, "Already uptodate!");
1193 *result = head;
1194 return 1;
1195 }
1197 code = git_merge_trees(index_only, common, head, merge);
1199 if (code != 0)
1200 die("merging of trees %s and %s failed",
1201 sha1_to_hex(head->object.sha1),
1202 sha1_to_hex(merge->object.sha1));
1204 if (unmerged_index()) {
1205 struct path_list *entries, *re_head, *re_merge;
1206 int i;
1207 path_list_clear(¤t_file_set, 1);
1208 path_list_clear(¤t_directory_set, 1);
1209 get_files_dirs(head);
1210 get_files_dirs(merge);
1212 entries = get_unmerged();
1213 re_head = get_renames(head, common, head, merge, entries);
1214 re_merge = get_renames(merge, common, head, merge, entries);
1215 clean = process_renames(re_head, re_merge,
1216 branch1, branch2);
1217 total_cnt += entries->nr;
1218 for (i = 0; i < entries->nr; i++, merged_cnt++) {
1219 const char *path = entries->items[i].path;
1220 struct stage_data *e = entries->items[i].util;
1221 if (!e->processed
1222 && !process_entry(path, e, branch1, branch2))
1223 clean = 0;
1224 if (do_progress)
1225 display_progress();
1226 }
1228 path_list_clear(re_merge, 0);
1229 path_list_clear(re_head, 0);
1230 path_list_clear(entries, 1);
1232 }
1233 else
1234 clean = 1;
1236 if (index_only)
1237 *result = git_write_tree();
1239 return clean;
1240 }
1242 static struct commit_list *reverse_commit_list(struct commit_list *list)
1243 {
1244 struct commit_list *next = NULL, *current, *backup;
1245 for (current = list; current; current = backup) {
1246 backup = current->next;
1247 current->next = next;
1248 next = current;
1249 }
1250 return next;
1251 }
1253 /*
1254 * Merge the commits h1 and h2, return the resulting virtual
1255 * commit object and a flag indicating the cleanness of the merge.
1256 */
1257 static int merge(struct commit *h1,
1258 struct commit *h2,
1259 const char *branch1,
1260 const char *branch2,
1261 struct commit_list *ca,
1262 struct commit **result)
1263 {
1264 struct commit_list *iter;
1265 struct commit *merged_common_ancestors;
1266 struct tree *mrtree;
1267 int clean;
1269 if (show(4)) {
1270 output(4, "Merging:");
1271 output_commit_title(h1);
1272 output_commit_title(h2);
1273 }
1275 if (!ca) {
1276 ca = get_merge_bases(h1, h2, 1);
1277 ca = reverse_commit_list(ca);
1278 }
1280 if (show(5)) {
1281 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1282 for (iter = ca; iter; iter = iter->next)
1283 output_commit_title(iter->item);
1284 }
1286 merged_common_ancestors = pop_commit(&ca);
1287 if (merged_common_ancestors == NULL) {
1288 /* if there is no common ancestor, make an empty tree */
1289 struct tree *tree = xcalloc(1, sizeof(struct tree));
1291 tree->object.parsed = 1;
1292 tree->object.type = OBJ_TREE;
1293 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1294 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1295 }
1297 for (iter = ca; iter; iter = iter->next) {
1298 call_depth++;
1299 /*
1300 * When the merge fails, the result contains files
1301 * with conflict markers. The cleanness flag is
1302 * ignored, it was never actually used, as result of
1303 * merge_trees has always overwritten it: the committed
1304 * "conflicts" were already resolved.
1305 */
1306 discard_cache();
1307 merge(merged_common_ancestors, iter->item,
1308 "Temporary merge branch 1",
1309 "Temporary merge branch 2",
1310 NULL,
1311 &merged_common_ancestors);
1312 call_depth--;
1314 if (!merged_common_ancestors)
1315 die("merge returned no commit");
1316 }
1318 discard_cache();
1319 if (!call_depth) {
1320 read_cache();
1321 index_only = 0;
1322 } else
1323 index_only = 1;
1325 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1326 branch1, branch2, &mrtree);
1328 if (index_only) {
1329 *result = make_virtual_commit(mrtree, "merged tree");
1330 commit_list_insert(h1, &(*result)->parents);
1331 commit_list_insert(h2, &(*result)->parents->next);
1332 }
1333 if (!call_depth && do_progress) {
1334 /* Make sure we end at 100% */
1335 if (!total_cnt)
1336 total_cnt = 1;
1337 merged_cnt = total_cnt;
1338 progress_update = 1;
1339 display_progress();
1340 fputc('\n', stderr);
1341 }
1342 flush_output();
1343 return clean;
1344 }
1346 static const char *better_branch_name(const char *branch)
1347 {
1348 static char githead_env[8 + 40 + 1];
1349 char *name;
1351 if (strlen(branch) != 40)
1352 return branch;
1353 sprintf(githead_env, "GITHEAD_%s", branch);
1354 name = getenv(githead_env);
1355 return name ? name : branch;
1356 }
1358 static struct commit *get_ref(const char *ref)
1359 {
1360 unsigned char sha1[20];
1361 struct object *object;
1363 if (get_sha1(ref, sha1))
1364 die("Could not resolve ref '%s'", ref);
1365 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1366 if (object->type == OBJ_TREE)
1367 return make_virtual_commit((struct tree*)object,
1368 better_branch_name(ref));
1369 if (object->type != OBJ_COMMIT)
1370 return NULL;
1371 if (parse_commit((struct commit *)object))
1372 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1373 return (struct commit *)object;
1374 }
1376 static int merge_config(const char *var, const char *value)
1377 {
1378 if (!strcasecmp(var, "merge.verbosity")) {
1379 verbosity = git_config_int(var, value);
1380 return 0;
1381 }
1382 return git_default_config(var, value);
1383 }
1385 int main(int argc, char *argv[])
1386 {
1387 static const char *bases[20];
1388 static unsigned bases_count = 0;
1389 int i, clean;
1390 const char *branch1, *branch2;
1391 struct commit *result, *h1, *h2;
1392 struct commit_list *ca = NULL;
1393 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1394 int index_fd;
1396 if (argv[0]) {
1397 int namelen = strlen(argv[0]);
1398 if (8 < namelen &&
1399 !strcmp(argv[0] + namelen - 8, "-subtree"))
1400 subtree_merge = 1;
1401 }
1403 git_config(merge_config);
1404 if (getenv("GIT_MERGE_VERBOSITY"))
1405 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1407 if (argc < 4)
1408 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1410 for (i = 1; i < argc; ++i) {
1411 if (!strcmp(argv[i], "--"))
1412 break;
1413 if (bases_count < sizeof(bases)/sizeof(*bases))
1414 bases[bases_count++] = argv[i];
1415 }
1416 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1417 die("Not handling anything other than two heads merge.");
1418 if (verbosity >= 5) {
1419 buffer_output = 0;
1420 do_progress = 0;
1421 }
1422 else
1423 do_progress = isatty(1);
1425 branch1 = argv[++i];
1426 branch2 = argv[++i];
1428 h1 = get_ref(branch1);
1429 h2 = get_ref(branch2);
1431 branch1 = better_branch_name(branch1);
1432 branch2 = better_branch_name(branch2);
1434 if (do_progress)
1435 setup_progress_signal();
1436 if (show(3))
1437 printf("Merging %s with %s\n", branch1, branch2);
1439 index_fd = hold_locked_index(lock, 1);
1441 for (i = 0; i < bases_count; i++) {
1442 struct commit *ancestor = get_ref(bases[i]);
1443 ca = commit_list_insert(ancestor, &ca);
1444 }
1445 clean = merge(h1, h2, branch1, branch2, ca, &result);
1447 if (active_cache_changed &&
1448 (write_cache(index_fd, active_cache, active_nr) ||
1449 close(index_fd) || commit_locked_index(lock)))
1450 die ("unable to write %s", get_index_file());
1452 return clean ? 0: 1;
1453 }