ae4dcfbe5b0b8b1e9a03df128b9d0b67706a371b
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 <stdarg.h>
7 #include <string.h>
8 #include <assert.h>
9 #include <sys/wait.h>
10 #include <sys/types.h>
11 #include <sys/stat.h>
12 #include <time.h>
13 #include "cache.h"
14 #include "cache-tree.h"
15 #include "commit.h"
16 #include "blob.h"
17 #include "tree-walk.h"
18 #include "diff.h"
19 #include "diffcore.h"
20 #include "run-command.h"
21 #include "tag.h"
22 #include "unpack-trees.h"
23 #include "path-list.h"
24 #include "xdiff-interface.h"
26 /*
27 * A virtual commit has
28 * - (const char *)commit->util set to the name, and
29 * - *(int *)commit->object.sha1 set to the virtual id.
30 */
32 static unsigned commit_list_count(const struct commit_list *l)
33 {
34 unsigned c = 0;
35 for (; l; l = l->next )
36 c++;
37 return c;
38 }
40 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
41 {
42 struct commit *commit = xcalloc(1, sizeof(struct commit));
43 static unsigned virtual_id = 1;
44 commit->tree = tree;
45 commit->util = (void*)comment;
46 *(int*)commit->object.sha1 = virtual_id++;
47 /* avoid warnings */
48 commit->object.parsed = 1;
49 return commit;
50 }
52 /*
53 * Since we use get_tree_entry(), which does not put the read object into
54 * the object pool, we cannot rely on a == b.
55 */
56 static int sha_eq(const unsigned char *a, const unsigned char *b)
57 {
58 if (!a && !b)
59 return 2;
60 return a && b && hashcmp(a, b) == 0;
61 }
63 /*
64 * Since we want to write the index eventually, we cannot reuse the index
65 * for these (temporary) data.
66 */
67 struct stage_data
68 {
69 struct
70 {
71 unsigned mode;
72 unsigned char sha[20];
73 } stages[4];
74 unsigned processed:1;
75 };
77 static struct path_list current_file_set = {NULL, 0, 0, 1};
78 static struct path_list current_directory_set = {NULL, 0, 0, 1};
80 static int output_indent = 0;
82 static void output(const char *fmt, ...)
83 {
84 va_list args;
85 int i;
86 for (i = output_indent; i--;)
87 fputs(" ", stdout);
88 va_start(args, fmt);
89 vfprintf(stdout, fmt, args);
90 va_end(args);
91 fputc('\n', stdout);
92 }
94 static void output_commit_title(struct commit *commit)
95 {
96 int i;
97 for (i = output_indent; i--;)
98 fputs(" ", stdout);
99 if (commit->util)
100 printf("virtual %s\n", (char *)commit->util);
101 else {
102 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
103 if (parse_commit(commit) != 0)
104 printf("(bad commit)\n");
105 else {
106 const char *s;
107 int len;
108 for (s = commit->buffer; *s; s++)
109 if (*s == '\n' && s[1] == '\n') {
110 s += 2;
111 break;
112 }
113 for (len = 0; s[len] && '\n' != s[len]; len++)
114 ; /* do nothing */
115 printf("%.*s\n", len, s);
116 }
117 }
118 }
120 static const char *current_index_file = NULL;
121 static const char *original_index_file;
122 static const char *temporary_index_file;
123 static int cache_dirty = 0;
125 static int flush_cache(void)
126 {
127 /* flush temporary index */
128 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
129 int fd = hold_lock_file_for_update(lock, current_index_file, 1);
130 if (write_cache(fd, active_cache, active_nr) ||
131 close(fd) || commit_lock_file(lock))
132 die ("unable to write %s", current_index_file);
133 discard_cache();
134 cache_dirty = 0;
135 return 0;
136 }
138 static void setup_index(int temp)
139 {
140 current_index_file = temp ? temporary_index_file: original_index_file;
141 if (cache_dirty) {
142 discard_cache();
143 cache_dirty = 0;
144 }
145 unlink(temporary_index_file);
146 discard_cache();
147 }
149 static struct cache_entry *make_cache_entry(unsigned int mode,
150 const unsigned char *sha1, const char *path, int stage, int refresh)
151 {
152 int size, len;
153 struct cache_entry *ce;
155 if (!verify_path(path))
156 return NULL;
158 len = strlen(path);
159 size = cache_entry_size(len);
160 ce = xcalloc(1, size);
162 hashcpy(ce->sha1, sha1);
163 memcpy(ce->name, path, len);
164 ce->ce_flags = create_ce_flags(len, stage);
165 ce->ce_mode = create_ce_mode(mode);
167 if (refresh)
168 return refresh_cache_entry(ce, 0);
170 return ce;
171 }
173 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
174 const char *path, int stage, int refresh, int options)
175 {
176 struct cache_entry *ce;
177 if (!cache_dirty)
178 read_cache_from(current_index_file);
179 cache_dirty++;
180 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
181 if (!ce)
182 return error("cache_addinfo failed: %s", strerror(cache_errno));
183 return add_cache_entry(ce, options);
184 }
186 /*
187 * This is a global variable which is used in a number of places but
188 * only written to in the 'merge' function.
189 *
190 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
191 * don't update the working directory.
192 * 0 => Leave unmerged entries in the cache and update
193 * the working directory.
194 */
195 static int index_only = 0;
197 static int git_read_tree(struct tree *tree)
198 {
199 int rc;
200 struct object_list *trees = NULL;
201 struct unpack_trees_options opts;
203 if (cache_dirty)
204 die("read-tree with dirty cache");
206 memset(&opts, 0, sizeof(opts));
207 object_list_append(&tree->object, &trees);
208 rc = unpack_trees(trees, &opts);
209 cache_tree_free(&active_cache_tree);
211 if (rc == 0)
212 cache_dirty = 1;
214 return rc;
215 }
217 static int git_merge_trees(int index_only,
218 struct tree *common,
219 struct tree *head,
220 struct tree *merge)
221 {
222 int rc;
223 struct object_list *trees = NULL;
224 struct unpack_trees_options opts;
226 if (!cache_dirty) {
227 read_cache_from(current_index_file);
228 cache_dirty = 1;
229 }
231 memset(&opts, 0, sizeof(opts));
232 if (index_only)
233 opts.index_only = 1;
234 else
235 opts.update = 1;
236 opts.merge = 1;
237 opts.head_idx = 2;
238 opts.fn = threeway_merge;
240 object_list_append(&common->object, &trees);
241 object_list_append(&head->object, &trees);
242 object_list_append(&merge->object, &trees);
244 rc = unpack_trees(trees, &opts);
245 cache_tree_free(&active_cache_tree);
247 cache_dirty = 1;
249 return rc;
250 }
252 static struct tree *git_write_tree(void)
253 {
254 struct tree *result = NULL;
256 if (cache_dirty) {
257 unsigned i;
258 for (i = 0; i < active_nr; i++) {
259 struct cache_entry *ce = active_cache[i];
260 if (ce_stage(ce))
261 return NULL;
262 }
263 } else
264 read_cache_from(current_index_file);
266 if (!active_cache_tree)
267 active_cache_tree = cache_tree();
269 if (!cache_tree_fully_valid(active_cache_tree) &&
270 cache_tree_update(active_cache_tree,
271 active_cache, active_nr, 0, 0) < 0)
272 die("error building trees");
274 result = lookup_tree(active_cache_tree->sha1);
276 flush_cache();
277 cache_dirty = 0;
279 return result;
280 }
282 static int save_files_dirs(const unsigned char *sha1,
283 const char *base, int baselen, const char *path,
284 unsigned int mode, int stage)
285 {
286 int len = strlen(path);
287 char *newpath = xmalloc(baselen + len + 1);
288 memcpy(newpath, base, baselen);
289 memcpy(newpath + baselen, path, len);
290 newpath[baselen + len] = '\0';
292 if (S_ISDIR(mode))
293 path_list_insert(newpath, ¤t_directory_set);
294 else
295 path_list_insert(newpath, ¤t_file_set);
296 free(newpath);
298 return READ_TREE_RECURSIVE;
299 }
301 static int get_files_dirs(struct tree *tree)
302 {
303 int n;
304 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
305 return 0;
306 n = current_file_set.nr + current_directory_set.nr;
307 return n;
308 }
310 /*
311 * Returns a index_entry instance which doesn't have to correspond to
312 * a real cache entry in Git's index.
313 */
314 static struct stage_data *insert_stage_data(const char *path,
315 struct tree *o, struct tree *a, struct tree *b,
316 struct path_list *entries)
317 {
318 struct path_list_item *item;
319 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
320 get_tree_entry(o->object.sha1, path,
321 e->stages[1].sha, &e->stages[1].mode);
322 get_tree_entry(a->object.sha1, path,
323 e->stages[2].sha, &e->stages[2].mode);
324 get_tree_entry(b->object.sha1, path,
325 e->stages[3].sha, &e->stages[3].mode);
326 item = path_list_insert(path, entries);
327 item->util = e;
328 return e;
329 }
331 /*
332 * Create a dictionary mapping file names to stage_data objects. The
333 * dictionary contains one entry for every path with a non-zero stage entry.
334 */
335 static struct path_list *get_unmerged(void)
336 {
337 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
338 int i;
340 unmerged->strdup_paths = 1;
341 if (!cache_dirty) {
342 read_cache_from(current_index_file);
343 cache_dirty++;
344 }
345 for (i = 0; i < active_nr; i++) {
346 struct path_list_item *item;
347 struct stage_data *e;
348 struct cache_entry *ce = active_cache[i];
349 if (!ce_stage(ce))
350 continue;
352 item = path_list_lookup(ce->name, unmerged);
353 if (!item) {
354 item = path_list_insert(ce->name, unmerged);
355 item->util = xcalloc(1, sizeof(struct stage_data));
356 }
357 e = item->util;
358 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
359 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
360 }
362 return unmerged;
363 }
365 struct rename
366 {
367 struct diff_filepair *pair;
368 struct stage_data *src_entry;
369 struct stage_data *dst_entry;
370 unsigned processed:1;
371 };
373 /*
374 * Get information of all renames which occured between 'o_tree' and
375 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
376 * 'b_tree') to be able to associate the correct cache entries with
377 * the rename information. 'tree' is always equal to either a_tree or b_tree.
378 */
379 static struct path_list *get_renames(struct tree *tree,
380 struct tree *o_tree,
381 struct tree *a_tree,
382 struct tree *b_tree,
383 struct path_list *entries)
384 {
385 int i;
386 struct path_list *renames;
387 struct diff_options opts;
389 renames = xcalloc(1, sizeof(struct path_list));
390 diff_setup(&opts);
391 opts.recursive = 1;
392 opts.detect_rename = DIFF_DETECT_RENAME;
393 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
394 if (diff_setup_done(&opts) < 0)
395 die("diff setup failed");
396 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
397 diffcore_std(&opts);
398 for (i = 0; i < diff_queued_diff.nr; ++i) {
399 struct path_list_item *item;
400 struct rename *re;
401 struct diff_filepair *pair = diff_queued_diff.queue[i];
402 if (pair->status != 'R') {
403 diff_free_filepair(pair);
404 continue;
405 }
406 re = xmalloc(sizeof(*re));
407 re->processed = 0;
408 re->pair = pair;
409 item = path_list_lookup(re->pair->one->path, entries);
410 if (!item)
411 re->src_entry = insert_stage_data(re->pair->one->path,
412 o_tree, a_tree, b_tree, entries);
413 else
414 re->src_entry = item->util;
416 item = path_list_lookup(re->pair->two->path, entries);
417 if (!item)
418 re->dst_entry = insert_stage_data(re->pair->two->path,
419 o_tree, a_tree, b_tree, entries);
420 else
421 re->dst_entry = item->util;
422 item = path_list_insert(pair->one->path, renames);
423 item->util = re;
424 }
425 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
426 diff_queued_diff.nr = 0;
427 diff_flush(&opts);
428 return renames;
429 }
431 static int update_stages(const char *path, struct diff_filespec *o,
432 struct diff_filespec *a, struct diff_filespec *b,
433 int clear)
434 {
435 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
436 if (clear)
437 if (remove_file_from_cache(path))
438 return -1;
439 if (o)
440 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
441 return -1;
442 if (a)
443 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
444 return -1;
445 if (b)
446 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
447 return -1;
448 return 0;
449 }
451 static int remove_path(const char *name)
452 {
453 int ret, len;
454 char *slash, *dirs;
456 ret = unlink(name);
457 if (ret)
458 return ret;
459 len = strlen(name);
460 dirs = xmalloc(len+1);
461 memcpy(dirs, name, len);
462 dirs[len] = '\0';
463 while ((slash = strrchr(name, '/'))) {
464 *slash = '\0';
465 len = slash - name;
466 if (rmdir(name) != 0)
467 break;
468 }
469 free(dirs);
470 return ret;
471 }
473 static int remove_file(int clean, const char *path, int no_wd)
474 {
475 int update_cache = index_only || clean;
476 int update_working_directory = !index_only && !no_wd;
478 if (update_cache) {
479 if (!cache_dirty)
480 read_cache_from(current_index_file);
481 cache_dirty++;
482 if (remove_file_from_cache(path))
483 return -1;
484 }
485 if (update_working_directory) {
486 unlink(path);
487 if (errno != ENOENT || errno != EISDIR)
488 return -1;
489 remove_path(path);
490 }
491 return 0;
492 }
494 static char *unique_path(const char *path, const char *branch)
495 {
496 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
497 int suffix = 0;
498 struct stat st;
499 char *p = newpath + strlen(path);
500 strcpy(newpath, path);
501 *(p++) = '~';
502 strcpy(p, branch);
503 for (; *p; ++p)
504 if ('/' == *p)
505 *p = '_';
506 while (path_list_has_path(¤t_file_set, newpath) ||
507 path_list_has_path(¤t_directory_set, newpath) ||
508 lstat(newpath, &st) == 0)
509 sprintf(p, "_%d", suffix++);
511 path_list_insert(newpath, ¤t_file_set);
512 return newpath;
513 }
515 static int mkdir_p(const char *path, unsigned long mode)
516 {
517 /* path points to cache entries, so xstrdup before messing with it */
518 char *buf = xstrdup(path);
519 int result = safe_create_leading_directories(buf);
520 free(buf);
521 return result;
522 }
524 static void flush_buffer(int fd, const char *buf, unsigned long size)
525 {
526 while (size > 0) {
527 long ret = xwrite(fd, buf, size);
528 if (ret < 0) {
529 /* Ignore epipe */
530 if (errno == EPIPE)
531 break;
532 die("merge-recursive: %s", strerror(errno));
533 } else if (!ret) {
534 die("merge-recursive: disk full?");
535 }
536 size -= ret;
537 buf += ret;
538 }
539 }
541 static void update_file_flags(const unsigned char *sha,
542 unsigned mode,
543 const char *path,
544 int update_cache,
545 int update_wd)
546 {
547 if (index_only)
548 update_wd = 0;
550 if (update_wd) {
551 char type[20];
552 void *buf;
553 unsigned long size;
555 buf = read_sha1_file(sha, type, &size);
556 if (!buf)
557 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
558 if (strcmp(type, blob_type) != 0)
559 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
561 if (S_ISREG(mode)) {
562 int fd;
563 if (mkdir_p(path, 0777))
564 die("failed to create path %s: %s", path, strerror(errno));
565 unlink(path);
566 if (mode & 0100)
567 mode = 0777;
568 else
569 mode = 0666;
570 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
571 if (fd < 0)
572 die("failed to open %s: %s", path, strerror(errno));
573 flush_buffer(fd, buf, size);
574 close(fd);
575 } else if (S_ISLNK(mode)) {
576 char *lnk = xmalloc(size + 1);
577 memcpy(lnk, buf, size);
578 lnk[size] = '\0';
579 mkdir_p(path, 0777);
580 unlink(lnk);
581 symlink(lnk, path);
582 } else
583 die("do not know what to do with %06o %s '%s'",
584 mode, sha1_to_hex(sha), path);
585 }
586 if (update_cache)
587 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
588 }
590 static void update_file(int clean,
591 const unsigned char *sha,
592 unsigned mode,
593 const char *path)
594 {
595 update_file_flags(sha, mode, path, index_only || clean, !index_only);
596 }
598 /* Low level file merging, update and removal */
600 struct merge_file_info
601 {
602 unsigned char sha[20];
603 unsigned mode;
604 unsigned clean:1,
605 merge:1;
606 };
608 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
609 {
610 unsigned long size;
611 char type[20];
613 if (!hashcmp(sha1, null_sha1)) {
614 mm->ptr = xstrdup("");
615 mm->size = 0;
616 return;
617 }
619 mm->ptr = read_sha1_file(sha1, type, &size);
620 if (!mm->ptr || strcmp(type, blob_type))
621 die("unable to read blob object %s", sha1_to_hex(sha1));
622 mm->size = size;
623 }
625 static struct merge_file_info merge_file(struct diff_filespec *o,
626 struct diff_filespec *a, struct diff_filespec *b,
627 const char *branch1, const char *branch2)
628 {
629 struct merge_file_info result;
630 result.merge = 0;
631 result.clean = 1;
633 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
634 result.clean = 0;
635 if (S_ISREG(a->mode)) {
636 result.mode = a->mode;
637 hashcpy(result.sha, a->sha1);
638 } else {
639 result.mode = b->mode;
640 hashcpy(result.sha, b->sha1);
641 }
642 } else {
643 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
644 result.merge = 1;
646 result.mode = a->mode == o->mode ? b->mode: a->mode;
648 if (sha_eq(a->sha1, o->sha1))
649 hashcpy(result.sha, b->sha1);
650 else if (sha_eq(b->sha1, o->sha1))
651 hashcpy(result.sha, a->sha1);
652 else if (S_ISREG(a->mode)) {
653 mmfile_t orig, src1, src2;
654 mmbuffer_t result_buf;
655 xpparam_t xpp;
656 char *name1, *name2;
657 int merge_status;
659 name1 = xstrdup(mkpath("%s/%s", branch1, a->path));
660 name2 = xstrdup(mkpath("%s/%s", branch2, b->path));
662 fill_mm(o->sha1, &orig);
663 fill_mm(a->sha1, &src1);
664 fill_mm(b->sha1, &src2);
666 memset(&xpp, 0, sizeof(xpp));
667 merge_status = xdl_merge(&orig,
668 &src1, name1,
669 &src2, name2,
670 &xpp, XDL_MERGE_ZEALOUS,
671 &result_buf);
672 free(name1);
673 free(name2);
674 free(orig.ptr);
675 free(src1.ptr);
676 free(src2.ptr);
678 if ((merge_status < 0) || !result_buf.ptr)
679 die("Failed to execute internal merge");
681 if (write_sha1_file(result_buf.ptr, result_buf.size,
682 blob_type, result.sha))
683 die("Unable to add %s to database",
684 a->path);
686 free(result_buf.ptr);
687 result.clean = (merge_status == 0);
688 } else {
689 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
690 die("cannot merge modes?");
692 hashcpy(result.sha, a->sha1);
694 if (!sha_eq(a->sha1, b->sha1))
695 result.clean = 0;
696 }
697 }
699 return result;
700 }
702 static void conflict_rename_rename(struct rename *ren1,
703 const char *branch1,
704 struct rename *ren2,
705 const char *branch2)
706 {
707 char *del[2];
708 int delp = 0;
709 const char *ren1_dst = ren1->pair->two->path;
710 const char *ren2_dst = ren2->pair->two->path;
711 const char *dst_name1 = ren1_dst;
712 const char *dst_name2 = ren2_dst;
713 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
714 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
715 output("%s is a directory in %s adding as %s instead",
716 ren1_dst, branch2, dst_name1);
717 remove_file(0, ren1_dst, 0);
718 }
719 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
720 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
721 output("%s is a directory in %s adding as %s instead",
722 ren2_dst, branch1, dst_name2);
723 remove_file(0, ren2_dst, 0);
724 }
725 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
726 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
727 while (delp--)
728 free(del[delp]);
729 }
731 static void conflict_rename_dir(struct rename *ren1,
732 const char *branch1)
733 {
734 char *new_path = unique_path(ren1->pair->two->path, branch1);
735 output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
736 remove_file(0, ren1->pair->two->path, 0);
737 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
738 free(new_path);
739 }
741 static void conflict_rename_rename_2(struct rename *ren1,
742 const char *branch1,
743 struct rename *ren2,
744 const char *branch2)
745 {
746 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
747 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
748 output("Renaming %s to %s and %s to %s instead",
749 ren1->pair->one->path, new_path1,
750 ren2->pair->one->path, new_path2);
751 remove_file(0, ren1->pair->two->path, 0);
752 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
753 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
754 free(new_path2);
755 free(new_path1);
756 }
758 static int process_renames(struct path_list *a_renames,
759 struct path_list *b_renames,
760 const char *a_branch,
761 const char *b_branch)
762 {
763 int clean_merge = 1, i, j;
764 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
765 const struct rename *sre;
767 for (i = 0; i < a_renames->nr; i++) {
768 sre = a_renames->items[i].util;
769 path_list_insert(sre->pair->two->path, &a_by_dst)->util
770 = sre->dst_entry;
771 }
772 for (i = 0; i < b_renames->nr; i++) {
773 sre = b_renames->items[i].util;
774 path_list_insert(sre->pair->two->path, &b_by_dst)->util
775 = sre->dst_entry;
776 }
778 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
779 int compare;
780 char *src;
781 struct path_list *renames1, *renames2, *renames2Dst;
782 struct rename *ren1 = NULL, *ren2 = NULL;
783 const char *branch1, *branch2;
784 const char *ren1_src, *ren1_dst;
786 if (i >= a_renames->nr) {
787 compare = 1;
788 ren2 = b_renames->items[j++].util;
789 } else if (j >= b_renames->nr) {
790 compare = -1;
791 ren1 = a_renames->items[i++].util;
792 } else {
793 compare = strcmp(a_renames->items[i].path,
794 b_renames->items[j].path);
795 if (compare <= 0)
796 ren1 = a_renames->items[i++].util;
797 if (compare >= 0)
798 ren2 = b_renames->items[j++].util;
799 }
801 /* TODO: refactor, so that 1/2 are not needed */
802 if (ren1) {
803 renames1 = a_renames;
804 renames2 = b_renames;
805 renames2Dst = &b_by_dst;
806 branch1 = a_branch;
807 branch2 = b_branch;
808 } else {
809 struct rename *tmp;
810 renames1 = b_renames;
811 renames2 = a_renames;
812 renames2Dst = &a_by_dst;
813 branch1 = b_branch;
814 branch2 = a_branch;
815 tmp = ren2;
816 ren2 = ren1;
817 ren1 = tmp;
818 }
819 src = ren1->pair->one->path;
821 ren1->dst_entry->processed = 1;
822 ren1->src_entry->processed = 1;
824 if (ren1->processed)
825 continue;
826 ren1->processed = 1;
828 ren1_src = ren1->pair->one->path;
829 ren1_dst = ren1->pair->two->path;
831 if (ren2) {
832 const char *ren2_src = ren2->pair->one->path;
833 const char *ren2_dst = ren2->pair->two->path;
834 /* Renamed in 1 and renamed in 2 */
835 if (strcmp(ren1_src, ren2_src) != 0)
836 die("ren1.src != ren2.src");
837 ren2->dst_entry->processed = 1;
838 ren2->processed = 1;
839 if (strcmp(ren1_dst, ren2_dst) != 0) {
840 clean_merge = 0;
841 output("CONFLICT (rename/rename): "
842 "Rename %s->%s in branch %s "
843 "rename %s->%s in %s",
844 src, ren1_dst, branch1,
845 src, ren2_dst, branch2);
846 conflict_rename_rename(ren1, branch1, ren2, branch2);
847 } else {
848 struct merge_file_info mfi;
849 remove_file(1, ren1_src, 1);
850 mfi = merge_file(ren1->pair->one,
851 ren1->pair->two,
852 ren2->pair->two,
853 branch1,
854 branch2);
855 if (mfi.merge || !mfi.clean)
856 output("Renaming %s->%s", src, ren1_dst);
858 if (mfi.merge)
859 output("Auto-merging %s", ren1_dst);
861 if (!mfi.clean) {
862 output("CONFLICT (content): merge conflict in %s",
863 ren1_dst);
864 clean_merge = 0;
866 if (!index_only)
867 update_stages(ren1_dst,
868 ren1->pair->one,
869 ren1->pair->two,
870 ren2->pair->two,
871 1 /* clear */);
872 }
873 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
874 }
875 } else {
876 /* Renamed in 1, maybe changed in 2 */
877 struct path_list_item *item;
878 /* we only use sha1 and mode of these */
879 struct diff_filespec src_other, dst_other;
880 int try_merge, stage = a_renames == renames1 ? 3: 2;
882 remove_file(1, ren1_src, index_only);
884 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
885 src_other.mode = ren1->src_entry->stages[stage].mode;
886 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
887 dst_other.mode = ren1->dst_entry->stages[stage].mode;
889 try_merge = 0;
891 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
892 clean_merge = 0;
893 output("CONFLICT (rename/directory): Rename %s->%s in %s "
894 " directory %s added in %s",
895 ren1_src, ren1_dst, branch1,
896 ren1_dst, branch2);
897 conflict_rename_dir(ren1, branch1);
898 } else if (sha_eq(src_other.sha1, null_sha1)) {
899 clean_merge = 0;
900 output("CONFLICT (rename/delete): Rename %s->%s in %s "
901 "and deleted in %s",
902 ren1_src, ren1_dst, branch1,
903 branch2);
904 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
905 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
906 const char *new_path;
907 clean_merge = 0;
908 try_merge = 1;
909 output("CONFLICT (rename/add): Rename %s->%s in %s. "
910 "%s added in %s",
911 ren1_src, ren1_dst, branch1,
912 ren1_dst, branch2);
913 new_path = unique_path(ren1_dst, branch2);
914 output("Adding as %s instead", new_path);
915 update_file(0, dst_other.sha1, dst_other.mode, new_path);
916 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
917 ren2 = item->util;
918 clean_merge = 0;
919 ren2->processed = 1;
920 output("CONFLICT (rename/rename): Rename %s->%s in %s. "
921 "Rename %s->%s in %s",
922 ren1_src, ren1_dst, branch1,
923 ren2->pair->one->path, ren2->pair->two->path, branch2);
924 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
925 } else
926 try_merge = 1;
928 if (try_merge) {
929 struct diff_filespec *o, *a, *b;
930 struct merge_file_info mfi;
931 src_other.path = (char *)ren1_src;
933 o = ren1->pair->one;
934 if (a_renames == renames1) {
935 a = ren1->pair->two;
936 b = &src_other;
937 } else {
938 b = ren1->pair->two;
939 a = &src_other;
940 }
941 mfi = merge_file(o, a, b,
942 a_branch, b_branch);
944 if (mfi.merge || !mfi.clean)
945 output("Renaming %s => %s", ren1_src, ren1_dst);
946 if (mfi.merge)
947 output("Auto-merging %s", ren1_dst);
948 if (!mfi.clean) {
949 output("CONFLICT (rename/modify): Merge conflict in %s",
950 ren1_dst);
951 clean_merge = 0;
953 if (!index_only)
954 update_stages(ren1_dst,
955 o, a, b, 1);
956 }
957 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
958 }
959 }
960 }
961 path_list_clear(&a_by_dst, 0);
962 path_list_clear(&b_by_dst, 0);
964 if (cache_dirty)
965 flush_cache();
966 return clean_merge;
967 }
969 static unsigned char *has_sha(const unsigned char *sha)
970 {
971 return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
972 }
974 /* Per entry merge function */
975 static int process_entry(const char *path, struct stage_data *entry,
976 const char *branch1,
977 const char *branch2)
978 {
979 /*
980 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
981 print_index_entry("\tpath: ", entry);
982 */
983 int clean_merge = 1;
984 unsigned char *o_sha = has_sha(entry->stages[1].sha);
985 unsigned char *a_sha = has_sha(entry->stages[2].sha);
986 unsigned char *b_sha = has_sha(entry->stages[3].sha);
987 unsigned o_mode = entry->stages[1].mode;
988 unsigned a_mode = entry->stages[2].mode;
989 unsigned b_mode = entry->stages[3].mode;
991 if (o_sha && (!a_sha || !b_sha)) {
992 /* Case A: Deleted in one */
993 if ((!a_sha && !b_sha) ||
994 (sha_eq(a_sha, o_sha) && !b_sha) ||
995 (!a_sha && sha_eq(b_sha, o_sha))) {
996 /* Deleted in both or deleted in one and
997 * unchanged in the other */
998 if (a_sha)
999 output("Removing %s", path);
1000 /* do not touch working file if it did not exist */
1001 remove_file(1, path, !a_sha);
1002 } else {
1003 /* Deleted in one and changed in the other */
1004 clean_merge = 0;
1005 if (!a_sha) {
1006 output("CONFLICT (delete/modify): %s deleted in %s "
1007 "and modified in %s. Version %s of %s left in tree.",
1008 path, branch1,
1009 branch2, branch2, path);
1010 update_file(0, b_sha, b_mode, path);
1011 } else {
1012 output("CONFLICT (delete/modify): %s deleted in %s "
1013 "and modified in %s. Version %s of %s left in tree.",
1014 path, branch2,
1015 branch1, branch1, path);
1016 update_file(0, a_sha, a_mode, path);
1017 }
1018 }
1020 } else if ((!o_sha && a_sha && !b_sha) ||
1021 (!o_sha && !a_sha && b_sha)) {
1022 /* Case B: Added in one. */
1023 const char *add_branch;
1024 const char *other_branch;
1025 unsigned mode;
1026 const unsigned char *sha;
1027 const char *conf;
1029 if (a_sha) {
1030 add_branch = branch1;
1031 other_branch = branch2;
1032 mode = a_mode;
1033 sha = a_sha;
1034 conf = "file/directory";
1035 } else {
1036 add_branch = branch2;
1037 other_branch = branch1;
1038 mode = b_mode;
1039 sha = b_sha;
1040 conf = "directory/file";
1041 }
1042 if (path_list_has_path(¤t_directory_set, path)) {
1043 const char *new_path = unique_path(path, add_branch);
1044 clean_merge = 0;
1045 output("CONFLICT (%s): There is a directory with name %s in %s. "
1046 "Adding %s as %s",
1047 conf, path, other_branch, path, new_path);
1048 remove_file(0, path, 0);
1049 update_file(0, sha, mode, new_path);
1050 } else {
1051 output("Adding %s", path);
1052 update_file(1, sha, mode, path);
1053 }
1054 } else if (a_sha && b_sha) {
1055 /* Case C: Added in both (check for same permissions) and */
1056 /* case D: Modified in both, but differently. */
1057 const char *reason = "content";
1058 struct merge_file_info mfi;
1059 struct diff_filespec o, a, b;
1061 if (!o_sha) {
1062 reason = "add/add";
1063 o_sha = (unsigned char *)null_sha1;
1064 }
1065 output("Auto-merging %s", path);
1066 o.path = a.path = b.path = (char *)path;
1067 hashcpy(o.sha1, o_sha);
1068 o.mode = o_mode;
1069 hashcpy(a.sha1, a_sha);
1070 a.mode = a_mode;
1071 hashcpy(b.sha1, b_sha);
1072 b.mode = b_mode;
1074 mfi = merge_file(&o, &a, &b,
1075 branch1, branch2);
1077 if (mfi.clean)
1078 update_file(1, mfi.sha, mfi.mode, path);
1079 else {
1080 clean_merge = 0;
1081 output("CONFLICT (%s): Merge conflict in %s",
1082 reason, path);
1084 if (index_only)
1085 update_file(0, mfi.sha, mfi.mode, path);
1086 else
1087 update_file_flags(mfi.sha, mfi.mode, path,
1088 0 /* update_cache */, 1 /* update_working_directory */);
1089 }
1090 } else
1091 die("Fatal merge failure, shouldn't happen.");
1093 if (cache_dirty)
1094 flush_cache();
1096 return clean_merge;
1097 }
1099 static int merge_trees(struct tree *head,
1100 struct tree *merge,
1101 struct tree *common,
1102 const char *branch1,
1103 const char *branch2,
1104 struct tree **result)
1105 {
1106 int code, clean;
1107 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1108 output("Already uptodate!");
1109 *result = head;
1110 return 1;
1111 }
1113 code = git_merge_trees(index_only, common, head, merge);
1115 if (code != 0)
1116 die("merging of trees %s and %s failed",
1117 sha1_to_hex(head->object.sha1),
1118 sha1_to_hex(merge->object.sha1));
1120 *result = git_write_tree();
1122 if (!*result) {
1123 struct path_list *entries, *re_head, *re_merge;
1124 int i;
1125 path_list_clear(¤t_file_set, 1);
1126 path_list_clear(¤t_directory_set, 1);
1127 get_files_dirs(head);
1128 get_files_dirs(merge);
1130 entries = get_unmerged();
1131 re_head = get_renames(head, common, head, merge, entries);
1132 re_merge = get_renames(merge, common, head, merge, entries);
1133 clean = process_renames(re_head, re_merge,
1134 branch1, branch2);
1135 for (i = 0; i < entries->nr; i++) {
1136 const char *path = entries->items[i].path;
1137 struct stage_data *e = entries->items[i].util;
1138 if (e->processed)
1139 continue;
1140 if (!process_entry(path, e, branch1, branch2))
1141 clean = 0;
1142 }
1144 path_list_clear(re_merge, 0);
1145 path_list_clear(re_head, 0);
1146 path_list_clear(entries, 1);
1148 if (clean || index_only)
1149 *result = git_write_tree();
1150 else
1151 *result = NULL;
1152 } else {
1153 clean = 1;
1154 printf("merging of trees %s and %s resulted in %s\n",
1155 sha1_to_hex(head->object.sha1),
1156 sha1_to_hex(merge->object.sha1),
1157 sha1_to_hex((*result)->object.sha1));
1158 }
1160 return clean;
1161 }
1163 static struct commit_list *reverse_commit_list(struct commit_list *list)
1164 {
1165 struct commit_list *next = NULL, *current, *backup;
1166 for (current = list; current; current = backup) {
1167 backup = current->next;
1168 current->next = next;
1169 next = current;
1170 }
1171 return next;
1172 }
1174 /*
1175 * Merge the commits h1 and h2, return the resulting virtual
1176 * commit object and a flag indicating the cleaness of the merge.
1177 */
1178 static int merge(struct commit *h1,
1179 struct commit *h2,
1180 const char *branch1,
1181 const char *branch2,
1182 int call_depth /* =0 */,
1183 struct commit *ancestor /* =None */,
1184 struct commit **result)
1185 {
1186 struct commit_list *ca = NULL, *iter;
1187 struct commit *merged_common_ancestors;
1188 struct tree *mrtree;
1189 int clean;
1191 output("Merging:");
1192 output_commit_title(h1);
1193 output_commit_title(h2);
1195 if (ancestor)
1196 commit_list_insert(ancestor, &ca);
1197 else
1198 ca = reverse_commit_list(get_merge_bases(h1, h2, 1));
1200 output("found %u common ancestor(s):", commit_list_count(ca));
1201 for (iter = ca; iter; iter = iter->next)
1202 output_commit_title(iter->item);
1204 merged_common_ancestors = pop_commit(&ca);
1205 if (merged_common_ancestors == NULL) {
1206 /* if there is no common ancestor, make an empty tree */
1207 struct tree *tree = xcalloc(1, sizeof(struct tree));
1209 tree->object.parsed = 1;
1210 tree->object.type = OBJ_TREE;
1211 write_sha1_file(NULL, 0, tree_type, tree->object.sha1);
1212 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1213 }
1215 for (iter = ca; iter; iter = iter->next) {
1216 output_indent = call_depth + 1;
1217 /*
1218 * When the merge fails, the result contains files
1219 * with conflict markers. The cleanness flag is
1220 * ignored, it was never acutally used, as result of
1221 * merge_trees has always overwritten it: the commited
1222 * "conflicts" were already resolved.
1223 */
1224 merge(merged_common_ancestors, iter->item,
1225 "Temporary merge branch 1",
1226 "Temporary merge branch 2",
1227 call_depth + 1,
1228 NULL,
1229 &merged_common_ancestors);
1230 output_indent = call_depth;
1232 if (!merged_common_ancestors)
1233 die("merge returned no commit");
1234 }
1236 if (call_depth == 0) {
1237 setup_index(0 /* $GIT_DIR/index */);
1238 index_only = 0;
1239 } else {
1240 setup_index(1 /* temporary index */);
1241 git_read_tree(h1->tree);
1242 index_only = 1;
1243 }
1245 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1246 branch1, branch2, &mrtree);
1248 if (!ancestor && (clean || index_only)) {
1249 *result = make_virtual_commit(mrtree, "merged tree");
1250 commit_list_insert(h1, &(*result)->parents);
1251 commit_list_insert(h2, &(*result)->parents->next);
1252 } else
1253 *result = NULL;
1255 return clean;
1256 }
1258 static struct commit *get_ref(const char *ref)
1259 {
1260 unsigned char sha1[20];
1261 struct object *object;
1263 if (get_sha1(ref, sha1))
1264 die("Could not resolve ref '%s'", ref);
1265 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1266 if (object->type != OBJ_COMMIT)
1267 return NULL;
1268 if (parse_commit((struct commit *)object))
1269 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1270 return (struct commit *)object;
1271 }
1273 int main(int argc, char *argv[])
1274 {
1275 static const char *bases[2];
1276 static unsigned bases_count = 0;
1277 int i, clean;
1278 const char *branch1, *branch2;
1279 struct commit *result, *h1, *h2;
1281 git_config(git_default_config); /* core.filemode */
1282 original_index_file = getenv(INDEX_ENVIRONMENT);
1284 if (!original_index_file)
1285 original_index_file = xstrdup(git_path("index"));
1287 temporary_index_file = xstrdup(git_path("mrg-rcrsv-tmp-idx"));
1289 if (argc < 4)
1290 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1292 for (i = 1; i < argc; ++i) {
1293 if (!strcmp(argv[i], "--"))
1294 break;
1295 if (bases_count < sizeof(bases)/sizeof(*bases))
1296 bases[bases_count++] = argv[i];
1297 }
1298 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1299 die("Not handling anything other than two heads merge.");
1301 branch1 = argv[++i];
1302 branch2 = argv[++i];
1303 printf("Merging %s with %s\n", branch1, branch2);
1305 h1 = get_ref(branch1);
1306 h2 = get_ref(branch2);
1308 if (bases_count == 1) {
1309 struct commit *ancestor = get_ref(bases[0]);
1310 clean = merge(h1, h2, branch1, branch2, 0, ancestor, &result);
1311 } else
1312 clean = merge(h1, h2, branch1, branch2, 0, NULL, &result);
1314 if (cache_dirty)
1315 flush_cache();
1317 return clean ? 0: 1;
1318 }
1320 /*
1321 vim: sw=8 noet
1322 */