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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 <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"
25 /*
26 * A virtual commit has
27 * - (const char *)commit->util set to the name, and
28 * - *(int *)commit->object.sha1 set to the virtual id.
29 */
31 static unsigned commit_list_count(const struct commit_list *l)
32 {
33 unsigned c = 0;
34 for (; l; l = l->next )
35 c++;
36 return c;
37 }
39 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
40 {
41 struct commit *commit = xcalloc(1, sizeof(struct commit));
42 static unsigned virtual_id = 1;
43 commit->tree = tree;
44 commit->util = (void*)comment;
45 *(int*)commit->object.sha1 = virtual_id++;
46 /* avoid warnings */
47 commit->object.parsed = 1;
48 return commit;
49 }
51 /*
52 * Since we use get_tree_entry(), which does not put the read object into
53 * the object pool, we cannot rely on a == b.
54 */
55 static int sha_eq(const unsigned char *a, const unsigned char *b)
56 {
57 if (!a && !b)
58 return 2;
59 return a && b && memcmp(a, b, 20) == 0;
60 }
62 /*
63 * Since we want to write the index eventually, we cannot reuse the index
64 * for these (temporary) data.
65 */
66 struct stage_data
67 {
68 struct
69 {
70 unsigned mode;
71 unsigned char sha[20];
72 } stages[4];
73 unsigned processed:1;
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 output_indent = 0;
81 static void output(const char *fmt, ...)
82 {
83 va_list args;
84 int i;
85 for (i = output_indent; i--;)
86 fputs(" ", stdout);
87 va_start(args, fmt);
88 vfprintf(stdout, fmt, args);
89 va_end(args);
90 fputc('\n', stdout);
91 }
93 static void output_commit_title(struct commit *commit)
94 {
95 int i;
96 for (i = output_indent; i--;)
97 fputs(" ", stdout);
98 if (commit->util)
99 printf("virtual %s\n", (char *)commit->util);
100 else {
101 printf("%s ", sha1_to_hex(commit->object.sha1));
102 if (parse_commit(commit) != 0)
103 printf("(bad commit)\n");
104 else {
105 const char *s;
106 int len;
107 for (s = commit->buffer; *s; s++)
108 if (*s == '\n' && s[1] == '\n') {
109 s += 2;
110 break;
111 }
112 for (len = 0; s[len] && '\n' != s[len]; len++)
113 ; /* do nothing */
114 printf("%.*s\n", len, s);
115 }
116 }
117 }
119 static const char *original_index_file;
120 static const char *temporary_index_file;
121 static int cache_dirty = 0;
123 static int flush_cache(void)
124 {
125 /* flush temporary index */
126 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
127 int fd = hold_lock_file_for_update(lock, getenv("GIT_INDEX_FILE"));
128 if (fd < 0)
129 die("could not lock %s", lock->filename);
130 if (write_cache(fd, active_cache, active_nr) ||
131 close(fd) || commit_lock_file(lock))
132 die ("unable to write %s", getenv("GIT_INDEX_FILE"));
133 discard_cache();
134 cache_dirty = 0;
135 return 0;
136 }
138 static void setup_index(int temp)
139 {
140 const char *idx = temp ? temporary_index_file: original_index_file;
141 if (cache_dirty)
142 die("fatal: cache changed flush_cache();");
143 unlink(temporary_index_file);
144 setenv("GIT_INDEX_FILE", idx, 1);
145 discard_cache();
146 }
148 static struct cache_entry *make_cache_entry(unsigned int mode,
149 const unsigned char *sha1, const char *path, int stage, int refresh)
150 {
151 int size, len;
152 struct cache_entry *ce;
154 if (!verify_path(path))
155 return NULL;
157 len = strlen(path);
158 size = cache_entry_size(len);
159 ce = xcalloc(1, size);
161 memcpy(ce->sha1, sha1, 20);
162 memcpy(ce->name, path, len);
163 ce->ce_flags = create_ce_flags(len, stage);
164 ce->ce_mode = create_ce_mode(mode);
166 if (refresh)
167 return refresh_cache_entry(ce, 0);
169 return ce;
170 }
172 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
173 const char *path, int stage, int refresh, int options)
174 {
175 struct cache_entry *ce;
176 if (!cache_dirty)
177 read_cache_from(getenv("GIT_INDEX_FILE"));
178 cache_dirty++;
179 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
180 if (!ce)
181 return error("cache_addinfo failed: %s", strerror(cache_errno));
182 return add_cache_entry(ce, options);
183 }
185 /*
186 * This is a global variable which is used in a number of places but
187 * only written to in the 'merge' function.
188 *
189 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
190 * don't update the working directory.
191 * 0 => Leave unmerged entries in the cache and update
192 * the working directory.
193 */
194 static int index_only = 0;
196 static int git_read_tree(struct tree *tree)
197 {
198 int rc;
199 struct object_list *trees = NULL;
200 struct unpack_trees_options opts;
202 if (cache_dirty)
203 die("read-tree with dirty cache");
205 memset(&opts, 0, sizeof(opts));
206 object_list_append(&tree->object, &trees);
207 rc = unpack_trees(trees, &opts);
208 cache_tree_free(&active_cache_tree);
210 if (rc == 0)
211 cache_dirty = 1;
213 return rc;
214 }
216 static int git_merge_trees(int index_only,
217 struct tree *common,
218 struct tree *head,
219 struct tree *merge)
220 {
221 int rc;
222 struct object_list *trees = NULL;
223 struct unpack_trees_options opts;
225 if (!cache_dirty) {
226 read_cache_from(getenv("GIT_INDEX_FILE"));
227 cache_dirty = 1;
228 }
230 memset(&opts, 0, sizeof(opts));
231 if (index_only)
232 opts.index_only = 1;
233 else
234 opts.update = 1;
235 opts.merge = 1;
236 opts.head_idx = 2;
237 opts.fn = threeway_merge;
239 object_list_append(&common->object, &trees);
240 object_list_append(&head->object, &trees);
241 object_list_append(&merge->object, &trees);
243 rc = unpack_trees(trees, &opts);
244 cache_tree_free(&active_cache_tree);
246 cache_dirty = 1;
248 return rc;
249 }
251 /*
252 * TODO: this can be streamlined by refactoring builtin-write-tree.c
253 */
254 static struct tree *git_write_tree(void)
255 {
256 FILE *fp;
257 int rc;
258 char buf[41];
259 unsigned char sha1[20];
260 int ch;
261 unsigned i = 0;
262 if (cache_dirty) {
263 for (i = 0; i < active_nr; i++) {
264 struct cache_entry *ce = active_cache[i];
265 if (ce_stage(ce))
266 return NULL;
267 }
268 flush_cache();
269 }
270 fp = popen("git-write-tree 2>/dev/null", "r");
271 while ((ch = fgetc(fp)) != EOF)
272 if (i < sizeof(buf)-1 && ch >= '0' && ch <= 'f')
273 buf[i++] = ch;
274 else
275 break;
276 rc = pclose(fp);
277 if (rc == -1 || WEXITSTATUS(rc))
278 return NULL;
279 buf[i] = '\0';
280 if (get_sha1(buf, sha1) != 0)
281 return NULL;
282 return lookup_tree(sha1);
283 }
285 static int save_files_dirs(const unsigned char *sha1,
286 const char *base, int baselen, const char *path,
287 unsigned int mode, int stage)
288 {
289 int len = strlen(path);
290 char *newpath = malloc(baselen + len + 1);
291 memcpy(newpath, base, baselen);
292 memcpy(newpath + baselen, path, len);
293 newpath[baselen + len] = '\0';
295 if (S_ISDIR(mode))
296 path_list_insert(newpath, ¤t_directory_set);
297 else
298 path_list_insert(newpath, ¤t_file_set);
299 free(newpath);
301 return READ_TREE_RECURSIVE;
302 }
304 static int get_files_dirs(struct tree *tree)
305 {
306 int n;
307 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
308 return 0;
309 n = current_file_set.nr + current_directory_set.nr;
310 return n;
311 }
313 /*
314 * Returns a index_entry instance which doesn't have to correspond to
315 * a real cache entry in Git's index.
316 */
317 static struct stage_data *insert_stage_data(const char *path,
318 struct tree *o, struct tree *a, struct tree *b,
319 struct path_list *entries)
320 {
321 struct path_list_item *item;
322 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
323 get_tree_entry(o->object.sha1, path,
324 e->stages[1].sha, &e->stages[1].mode);
325 get_tree_entry(a->object.sha1, path,
326 e->stages[2].sha, &e->stages[2].mode);
327 get_tree_entry(b->object.sha1, path,
328 e->stages[3].sha, &e->stages[3].mode);
329 item = path_list_insert(path, entries);
330 item->util = e;
331 return e;
332 }
334 /*
335 * Create a dictionary mapping file names to stage_data objects. The
336 * dictionary contains one entry for every path with a non-zero stage entry.
337 */
338 static struct path_list *get_unmerged(void)
339 {
340 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
341 int i;
343 unmerged->strdup_paths = 1;
344 if (!cache_dirty) {
345 read_cache_from(getenv("GIT_INDEX_FILE"));
346 cache_dirty++;
347 }
348 for (i = 0; i < active_nr; i++) {
349 struct path_list_item *item;
350 struct stage_data *e;
351 struct cache_entry *ce = active_cache[i];
352 if (!ce_stage(ce))
353 continue;
355 item = path_list_lookup(ce->name, unmerged);
356 if (!item) {
357 item = path_list_insert(ce->name, unmerged);
358 item->util = xcalloc(1, sizeof(struct stage_data));
359 }
360 e = item->util;
361 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
362 memcpy(e->stages[ce_stage(ce)].sha, ce->sha1, 20);
363 }
365 return unmerged;
366 }
368 struct rename
369 {
370 struct diff_filepair *pair;
371 struct stage_data *src_entry;
372 struct stage_data *dst_entry;
373 unsigned processed:1;
374 };
376 /*
377 * Get information of all renames which occured between 'o_tree' and
378 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
379 * 'b_tree') to be able to associate the correct cache entries with
380 * the rename information. 'tree' is always equal to either a_tree or b_tree.
381 */
382 static struct path_list *get_renames(struct tree *tree,
383 struct tree *o_tree,
384 struct tree *a_tree,
385 struct tree *b_tree,
386 struct path_list *entries)
387 {
388 int i;
389 struct path_list *renames;
390 struct diff_options opts;
392 renames = xcalloc(1, sizeof(struct path_list));
393 diff_setup(&opts);
394 opts.recursive = 1;
395 opts.detect_rename = DIFF_DETECT_RENAME;
396 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
397 if (diff_setup_done(&opts) < 0)
398 die("diff setup failed");
399 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
400 diffcore_std(&opts);
401 for (i = 0; i < diff_queued_diff.nr; ++i) {
402 struct path_list_item *item;
403 struct rename *re;
404 struct diff_filepair *pair = diff_queued_diff.queue[i];
405 if (pair->status != 'R') {
406 diff_free_filepair(pair);
407 continue;
408 }
409 re = xmalloc(sizeof(*re));
410 re->processed = 0;
411 re->pair = pair;
412 item = path_list_lookup(re->pair->one->path, entries);
413 if (!item)
414 re->src_entry = insert_stage_data(re->pair->one->path,
415 o_tree, a_tree, b_tree, entries);
416 else
417 re->src_entry = item->util;
419 item = path_list_lookup(re->pair->two->path, entries);
420 if (!item)
421 re->dst_entry = insert_stage_data(re->pair->two->path,
422 o_tree, a_tree, b_tree, entries);
423 else
424 re->dst_entry = item->util;
425 item = path_list_insert(pair->one->path, renames);
426 item->util = re;
427 }
428 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
429 diff_queued_diff.nr = 0;
430 diff_flush(&opts);
431 return renames;
432 }
434 int update_stages(const char *path, struct diff_filespec *o,
435 struct diff_filespec *a, struct diff_filespec *b, int clear)
436 {
437 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
438 if (clear)
439 if (remove_file_from_cache(path))
440 return -1;
441 if (o)
442 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
443 return -1;
444 if (a)
445 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
446 return -1;
447 if (b)
448 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
449 return -1;
450 return 0;
451 }
453 static int remove_path(const char *name)
454 {
455 int ret, len;
456 char *slash, *dirs;
458 ret = unlink(name);
459 if (ret)
460 return ret;
461 len = strlen(name);
462 dirs = malloc(len+1);
463 memcpy(dirs, name, len);
464 dirs[len] = '\0';
465 while ((slash = strrchr(name, '/'))) {
466 *slash = '\0';
467 len = slash - name;
468 if (rmdir(name) != 0)
469 break;
470 }
471 free(dirs);
472 return ret;
473 }
475 /*
476 * TODO: once we no longer call external programs, we'd probably be better off
477 * not setting / getting the environment variable GIT_INDEX_FILE all the time.
478 */
479 int remove_file(int clean, const char *path)
480 {
481 int update_cache = index_only || clean;
482 int update_working_directory = !index_only;
484 if (update_cache) {
485 if (!cache_dirty)
486 read_cache_from(getenv("GIT_INDEX_FILE"));
487 cache_dirty++;
488 if (remove_file_from_cache(path))
489 return -1;
490 }
491 if (update_working_directory)
492 {
493 unlink(path);
494 if (errno != ENOENT || errno != EISDIR)
495 return -1;
496 remove_path(path);
497 }
498 return 0;
499 }
501 static char *unique_path(const char *path, const char *branch)
502 {
503 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
504 int suffix = 0;
505 struct stat st;
506 char *p = newpath + strlen(path);
507 strcpy(newpath, path);
508 *(p++) = '~';
509 strcpy(p, branch);
510 for (; *p; ++p)
511 if ('/' == *p)
512 *p = '_';
513 while (path_list_has_path(¤t_file_set, newpath) ||
514 path_list_has_path(¤t_directory_set, newpath) ||
515 lstat(newpath, &st) == 0)
516 sprintf(p, "_%d", suffix++);
518 path_list_insert(newpath, ¤t_file_set);
519 return newpath;
520 }
522 static int mkdir_p(const char *path, unsigned long mode)
523 {
524 /* path points to cache entries, so strdup before messing with it */
525 char *buf = strdup(path);
526 int result = safe_create_leading_directories(buf);
527 free(buf);
528 return result;
529 }
531 static void flush_buffer(int fd, const char *buf, unsigned long size)
532 {
533 while (size > 0) {
534 long ret = xwrite(fd, buf, size);
535 if (ret < 0) {
536 /* Ignore epipe */
537 if (errno == EPIPE)
538 break;
539 die("merge-recursive: %s", strerror(errno));
540 } else if (!ret) {
541 die("merge-recursive: disk full?");
542 }
543 size -= ret;
544 buf += ret;
545 }
546 }
548 void update_file_flags(const unsigned char *sha,
549 unsigned mode,
550 const char *path,
551 int update_cache,
552 int update_wd)
553 {
554 if (index_only)
555 update_wd = 0;
557 if (update_wd) {
558 char type[20];
559 void *buf;
560 unsigned long size;
562 buf = read_sha1_file(sha, type, &size);
563 if (!buf)
564 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
565 if (strcmp(type, blob_type) != 0)
566 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
568 if (S_ISREG(mode)) {
569 int fd;
570 if (mkdir_p(path, 0777))
571 die("failed to create path %s: %s", path, strerror(errno));
572 unlink(path);
573 if (mode & 0100)
574 mode = 0777;
575 else
576 mode = 0666;
577 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
578 if (fd < 0)
579 die("failed to open %s: %s", path, strerror(errno));
580 flush_buffer(fd, buf, size);
581 close(fd);
582 } else if (S_ISLNK(mode)) {
583 char *lnk = malloc(size + 1);
584 memcpy(lnk, buf, size);
585 lnk[size] = '\0';
586 mkdir_p(path, 0777);
587 unlink(lnk);
588 symlink(lnk, path);
589 } else
590 die("do not know what to do with %06o %s '%s'",
591 mode, sha1_to_hex(sha), path);
592 }
593 if (update_cache)
594 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
595 }
597 void update_file(int clean,
598 const unsigned char *sha,
599 unsigned mode,
600 const char *path)
601 {
602 update_file_flags(sha, mode, path, index_only || clean, !index_only);
603 }
605 /* Low level file merging, update and removal */
607 struct merge_file_info
608 {
609 unsigned char sha[20];
610 unsigned mode;
611 unsigned clean:1,
612 merge:1;
613 };
615 static char *git_unpack_file(const unsigned char *sha1, char *path)
616 {
617 void *buf;
618 char type[20];
619 unsigned long size;
620 int fd;
622 buf = read_sha1_file(sha1, type, &size);
623 if (!buf || strcmp(type, blob_type))
624 die("unable to read blob object %s", sha1_to_hex(sha1));
626 strcpy(path, ".merge_file_XXXXXX");
627 fd = mkstemp(path);
628 if (fd < 0)
629 die("unable to create temp-file");
630 flush_buffer(fd, buf, size);
631 close(fd);
632 return path;
633 }
635 static struct merge_file_info merge_file(struct diff_filespec *o,
636 struct diff_filespec *a, struct diff_filespec *b,
637 const char *branch1, const char *branch2)
638 {
639 struct merge_file_info result;
640 result.merge = 0;
641 result.clean = 1;
643 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
644 result.clean = 0;
645 if (S_ISREG(a->mode)) {
646 result.mode = a->mode;
647 memcpy(result.sha, a->sha1, 20);
648 } else {
649 result.mode = b->mode;
650 memcpy(result.sha, b->sha1, 20);
651 }
652 } else {
653 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
654 result.merge = 1;
656 result.mode = a->mode == o->mode ? b->mode: a->mode;
658 if (sha_eq(a->sha1, o->sha1))
659 memcpy(result.sha, b->sha1, 20);
660 else if (sha_eq(b->sha1, o->sha1))
661 memcpy(result.sha, a->sha1, 20);
662 else if (S_ISREG(a->mode)) {
663 int code = 1, fd;
664 struct stat st;
665 char orig[PATH_MAX];
666 char src1[PATH_MAX];
667 char src2[PATH_MAX];
668 const char *argv[] = {
669 "merge", "-L", NULL, "-L", NULL, "-L", NULL,
670 NULL, NULL, NULL,
671 NULL
672 };
673 char *la, *lb, *lo;
675 git_unpack_file(o->sha1, orig);
676 git_unpack_file(a->sha1, src1);
677 git_unpack_file(b->sha1, src2);
679 argv[2] = la = strdup(mkpath("%s/%s", branch1, a->path));
680 argv[6] = lb = strdup(mkpath("%s/%s", branch2, b->path));
681 argv[4] = lo = strdup(mkpath("orig/%s", o->path));
682 argv[7] = src1;
683 argv[8] = orig;
684 argv[9] = src2,
686 code = run_command_v(10, argv);
688 free(la);
689 free(lb);
690 free(lo);
691 if (code && code < -256) {
692 die("Failed to execute 'merge'. merge(1) is used as the "
693 "file-level merge tool. Is 'merge' in your path?");
694 }
695 fd = open(src1, O_RDONLY);
696 if (fd < 0 || fstat(fd, &st) < 0 ||
697 index_fd(result.sha, fd, &st, 1,
698 "blob"))
699 die("Unable to add %s to database", src1);
701 unlink(orig);
702 unlink(src1);
703 unlink(src2);
705 result.clean = WEXITSTATUS(code) == 0;
706 } else {
707 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
708 die("cannot merge modes?");
710 memcpy(result.sha, a->sha1, 20);
712 if (!sha_eq(a->sha1, b->sha1))
713 result.clean = 0;
714 }
715 }
717 return result;
718 }
720 static void conflict_rename_rename(struct rename *ren1,
721 const char *branch1,
722 struct rename *ren2,
723 const char *branch2)
724 {
725 char *del[2];
726 int delp = 0;
727 const char *ren1_dst = ren1->pair->two->path;
728 const char *ren2_dst = ren2->pair->two->path;
729 const char *dst_name1 = ren1_dst;
730 const char *dst_name2 = ren2_dst;
731 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
732 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
733 output("%s is a directory in %s adding as %s instead",
734 ren1_dst, branch2, dst_name1);
735 remove_file(0, ren1_dst);
736 }
737 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
738 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
739 output("%s is a directory in %s adding as %s instead",
740 ren2_dst, branch1, dst_name2);
741 remove_file(0, ren2_dst);
742 }
743 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
744 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
745 while (delp--)
746 free(del[delp]);
747 }
749 static void conflict_rename_dir(struct rename *ren1,
750 const char *branch1)
751 {
752 char *new_path = unique_path(ren1->pair->two->path, branch1);
753 output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
754 remove_file(0, ren1->pair->two->path);
755 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
756 free(new_path);
757 }
759 static void conflict_rename_rename_2(struct rename *ren1,
760 const char *branch1,
761 struct rename *ren2,
762 const char *branch2)
763 {
764 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
765 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
766 output("Renaming %s to %s and %s to %s instead",
767 ren1->pair->one->path, new_path1,
768 ren2->pair->one->path, new_path2);
769 remove_file(0, ren1->pair->two->path);
770 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
771 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
772 free(new_path2);
773 free(new_path1);
774 }
776 static int process_renames(struct path_list *a_renames,
777 struct path_list *b_renames,
778 const char *a_branch,
779 const char *b_branch)
780 {
781 int clean_merge = 1, i, j;
782 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
783 const struct rename *sre;
785 for (i = 0; i < a_renames->nr; i++) {
786 sre = a_renames->items[i].util;
787 path_list_insert(sre->pair->two->path, &a_by_dst)->util
788 = sre->dst_entry;
789 }
790 for (i = 0; i < b_renames->nr; i++) {
791 sre = b_renames->items[i].util;
792 path_list_insert(sre->pair->two->path, &b_by_dst)->util
793 = sre->dst_entry;
794 }
796 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
797 int compare;
798 char *src;
799 struct path_list *renames1, *renames2, *renames2Dst;
800 struct rename *ren1 = NULL, *ren2 = NULL;
801 const char *branch1, *branch2;
802 const char *ren1_src, *ren1_dst;
804 if (i >= a_renames->nr) {
805 compare = 1;
806 ren2 = b_renames->items[j++].util;
807 } else if (j >= b_renames->nr) {
808 compare = -1;
809 ren1 = a_renames->items[i++].util;
810 } else {
811 compare = strcmp(a_renames->items[i].path,
812 b_renames->items[j].path);
813 ren1 = a_renames->items[i++].util;
814 ren2 = b_renames->items[j++].util;
815 }
817 /* TODO: refactor, so that 1/2 are not needed */
818 if (ren1) {
819 renames1 = a_renames;
820 renames2 = b_renames;
821 renames2Dst = &b_by_dst;
822 branch1 = a_branch;
823 branch2 = b_branch;
824 } else {
825 struct rename *tmp;
826 renames1 = b_renames;
827 renames2 = a_renames;
828 renames2Dst = &a_by_dst;
829 branch1 = b_branch;
830 branch2 = a_branch;
831 tmp = ren2;
832 ren2 = ren1;
833 ren1 = tmp;
834 }
835 src = ren1->pair->one->path;
837 ren1->dst_entry->processed = 1;
838 ren1->src_entry->processed = 1;
840 if (ren1->processed)
841 continue;
842 ren1->processed = 1;
844 ren1_src = ren1->pair->one->path;
845 ren1_dst = ren1->pair->two->path;
847 if (ren2) {
848 const char *ren2_src = ren2->pair->one->path;
849 const char *ren2_dst = ren2->pair->two->path;
850 /* Renamed in 1 and renamed in 2 */
851 if (strcmp(ren1_src, ren2_src) != 0)
852 die("ren1.src != ren2.src");
853 ren2->dst_entry->processed = 1;
854 ren2->processed = 1;
855 if (strcmp(ren1_dst, ren2_dst) != 0) {
856 clean_merge = 0;
857 output("CONFLICT (rename/rename): "
858 "Rename %s->%s in branch %s "
859 "rename %s->%s in %s",
860 src, ren1_dst, branch1,
861 src, ren2_dst, branch2);
862 conflict_rename_rename(ren1, branch1, ren2, branch2);
863 } else {
864 struct merge_file_info mfi;
865 remove_file(1, ren1_src);
866 mfi = merge_file(ren1->pair->one,
867 ren1->pair->two,
868 ren2->pair->two,
869 branch1,
870 branch2);
871 if (mfi.merge || !mfi.clean)
872 output("Renaming %s->%s", src, ren1_dst);
874 if (mfi.merge)
875 output("Auto-merging %s", ren1_dst);
877 if (!mfi.clean) {
878 output("CONFLICT (content): merge conflict in %s",
879 ren1_dst);
880 clean_merge = 0;
882 if (!index_only)
883 update_stages(ren1_dst,
884 ren1->pair->one,
885 ren1->pair->two,
886 ren2->pair->two,
887 1 /* clear */);
888 }
889 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
890 }
891 } else {
892 /* Renamed in 1, maybe changed in 2 */
893 struct path_list_item *item;
894 /* we only use sha1 and mode of these */
895 struct diff_filespec src_other, dst_other;
896 int try_merge, stage = a_renames == renames1 ? 3: 2;
898 remove_file(1, ren1_src);
900 memcpy(src_other.sha1,
901 ren1->src_entry->stages[stage].sha, 20);
902 src_other.mode = ren1->src_entry->stages[stage].mode;
903 memcpy(dst_other.sha1,
904 ren1->dst_entry->stages[stage].sha, 20);
905 dst_other.mode = ren1->dst_entry->stages[stage].mode;
907 try_merge = 0;
909 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
910 clean_merge = 0;
911 output("CONFLICT (rename/directory): Rename %s->%s in %s "
912 " directory %s added in %s",
913 ren1_src, ren1_dst, branch1,
914 ren1_dst, branch2);
915 conflict_rename_dir(ren1, branch1);
916 } else if (sha_eq(src_other.sha1, null_sha1)) {
917 clean_merge = 0;
918 output("CONFLICT (rename/delete): Rename %s->%s in %s "
919 "and deleted in %s",
920 ren1_src, ren1_dst, branch1,
921 branch2);
922 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
923 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
924 const char *new_path;
925 clean_merge = 0;
926 try_merge = 1;
927 output("CONFLICT (rename/add): Rename %s->%s in %s. "
928 "%s added in %s",
929 ren1_src, ren1_dst, branch1,
930 ren1_dst, branch2);
931 new_path = unique_path(ren1_dst, branch2);
932 output("Adding as %s instead", new_path);
933 update_file(0, dst_other.sha1, dst_other.mode, new_path);
934 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
935 ren2 = item->util;
936 clean_merge = 0;
937 ren2->processed = 1;
938 output("CONFLICT (rename/rename): Rename %s->%s in %s. "
939 "Rename %s->%s in %s",
940 ren1_src, ren1_dst, branch1,
941 ren2->pair->one->path, ren2->pair->two->path, branch2);
942 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
943 } else
944 try_merge = 1;
946 if (try_merge) {
947 struct diff_filespec *o, *a, *b;
948 struct merge_file_info mfi;
949 src_other.path = (char *)ren1_src;
951 o = ren1->pair->one;
952 if (a_renames == renames1) {
953 a = ren1->pair->two;
954 b = &src_other;
955 } else {
956 b = ren1->pair->two;
957 a = &src_other;
958 }
959 mfi = merge_file(o, a, b,
960 a_branch, b_branch);
962 if (mfi.merge || !mfi.clean)
963 output("Renaming %s => %s", ren1_src, ren1_dst);
964 if (mfi.merge)
965 output("Auto-merging %s", ren1_dst);
966 if (!mfi.clean) {
967 output("CONFLICT (rename/modify): Merge conflict in %s",
968 ren1_dst);
969 clean_merge = 0;
971 if (!index_only)
972 update_stages(ren1_dst,
973 o, a, b, 1);
974 }
975 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
976 }
977 }
978 }
979 path_list_clear(&a_by_dst, 0);
980 path_list_clear(&b_by_dst, 0);
982 if (cache_dirty)
983 flush_cache();
984 return clean_merge;
985 }
987 static unsigned char *has_sha(const unsigned char *sha)
988 {
989 return memcmp(sha, null_sha1, 20) == 0 ? NULL: (unsigned char *)sha;
990 }
992 /* Per entry merge function */
993 static int process_entry(const char *path, struct stage_data *entry,
994 const char *branch1,
995 const char *branch2)
996 {
997 /*
998 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
999 print_index_entry("\tpath: ", entry);
1000 */
1001 int clean_merge = 1;
1002 unsigned char *o_sha = has_sha(entry->stages[1].sha);
1003 unsigned char *a_sha = has_sha(entry->stages[2].sha);
1004 unsigned char *b_sha = has_sha(entry->stages[3].sha);
1005 unsigned o_mode = entry->stages[1].mode;
1006 unsigned a_mode = entry->stages[2].mode;
1007 unsigned b_mode = entry->stages[3].mode;
1009 if (o_sha && (!a_sha || !b_sha)) {
1010 /* Case A: Deleted in one */
1011 if ((!a_sha && !b_sha) ||
1012 (sha_eq(a_sha, o_sha) && !b_sha) ||
1013 (!a_sha && sha_eq(b_sha, o_sha))) {
1014 /* Deleted in both or deleted in one and
1015 * unchanged in the other */
1016 if (a_sha)
1017 output("Removing %s", path);
1018 remove_file(1, path);
1019 } else {
1020 /* Deleted in one and changed in the other */
1021 clean_merge = 0;
1022 if (!a_sha) {
1023 output("CONFLICT (delete/modify): %s deleted in %s "
1024 "and modified in %s. Version %s of %s left in tree.",
1025 path, branch1,
1026 branch2, branch2, path);
1027 update_file(0, b_sha, b_mode, path);
1028 } else {
1029 output("CONFLICT (delete/modify): %s deleted in %s "
1030 "and modified in %s. Version %s of %s left in tree.",
1031 path, branch2,
1032 branch1, branch1, path);
1033 update_file(0, a_sha, a_mode, path);
1034 }
1035 }
1037 } else if ((!o_sha && a_sha && !b_sha) ||
1038 (!o_sha && !a_sha && b_sha)) {
1039 /* Case B: Added in one. */
1040 const char *add_branch;
1041 const char *other_branch;
1042 unsigned mode;
1043 const unsigned char *sha;
1044 const char *conf;
1046 if (a_sha) {
1047 add_branch = branch1;
1048 other_branch = branch2;
1049 mode = a_mode;
1050 sha = a_sha;
1051 conf = "file/directory";
1052 } else {
1053 add_branch = branch2;
1054 other_branch = branch1;
1055 mode = b_mode;
1056 sha = b_sha;
1057 conf = "directory/file";
1058 }
1059 if (path_list_has_path(¤t_directory_set, path)) {
1060 const char *new_path = unique_path(path, add_branch);
1061 clean_merge = 0;
1062 output("CONFLICT (%s): There is a directory with name %s in %s. "
1063 "Adding %s as %s",
1064 conf, path, other_branch, path, new_path);
1065 remove_file(0, path);
1066 update_file(0, sha, mode, new_path);
1067 } else {
1068 output("Adding %s", path);
1069 update_file(1, sha, mode, path);
1070 }
1071 } else if (!o_sha && a_sha && b_sha) {
1072 /* Case C: Added in both (check for same permissions). */
1073 if (sha_eq(a_sha, b_sha)) {
1074 if (a_mode != b_mode) {
1075 clean_merge = 0;
1076 output("CONFLICT: File %s added identically in both branches, "
1077 "but permissions conflict %06o->%06o",
1078 path, a_mode, b_mode);
1079 output("CONFLICT: adding with permission: %06o", a_mode);
1080 update_file(0, a_sha, a_mode, path);
1081 } else {
1082 /* This case is handled by git-read-tree */
1083 assert(0 && "This case must be handled by git-read-tree");
1084 }
1085 } else {
1086 const char *new_path1, *new_path2;
1087 clean_merge = 0;
1088 new_path1 = unique_path(path, branch1);
1089 new_path2 = unique_path(path, branch2);
1090 output("CONFLICT (add/add): File %s added non-identically "
1091 "in both branches. Adding as %s and %s instead.",
1092 path, new_path1, new_path2);
1093 remove_file(0, path);
1094 update_file(0, a_sha, a_mode, new_path1);
1095 update_file(0, b_sha, b_mode, new_path2);
1096 }
1098 } else if (o_sha && a_sha && b_sha) {
1099 /* case D: Modified in both, but differently. */
1100 struct merge_file_info mfi;
1101 struct diff_filespec o, a, b;
1103 output("Auto-merging %s", path);
1104 o.path = a.path = b.path = (char *)path;
1105 memcpy(o.sha1, o_sha, 20);
1106 o.mode = o_mode;
1107 memcpy(a.sha1, a_sha, 20);
1108 a.mode = a_mode;
1109 memcpy(b.sha1, b_sha, 20);
1110 b.mode = b_mode;
1112 mfi = merge_file(&o, &a, &b,
1113 branch1, branch2);
1115 if (mfi.clean)
1116 update_file(1, mfi.sha, mfi.mode, path);
1117 else {
1118 clean_merge = 0;
1119 output("CONFLICT (content): Merge conflict in %s", path);
1121 if (index_only)
1122 update_file(0, mfi.sha, mfi.mode, path);
1123 else
1124 update_file_flags(mfi.sha, mfi.mode, path,
1125 0 /* update_cache */, 1 /* update_working_directory */);
1126 }
1127 } else
1128 die("Fatal merge failure, shouldn't happen.");
1130 if (cache_dirty)
1131 flush_cache();
1133 return clean_merge;
1134 }
1136 static int merge_trees(struct tree *head,
1137 struct tree *merge,
1138 struct tree *common,
1139 const char *branch1,
1140 const char *branch2,
1141 struct tree **result)
1142 {
1143 int code, clean;
1144 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1145 output("Already uptodate!");
1146 *result = head;
1147 return 1;
1148 }
1150 code = git_merge_trees(index_only, common, head, merge);
1152 if (code != 0)
1153 die("merging of trees %s and %s failed",
1154 sha1_to_hex(head->object.sha1),
1155 sha1_to_hex(merge->object.sha1));
1157 *result = git_write_tree();
1159 if (!*result) {
1160 struct path_list *entries, *re_head, *re_merge;
1161 int i;
1162 path_list_clear(¤t_file_set, 1);
1163 path_list_clear(¤t_directory_set, 1);
1164 get_files_dirs(head);
1165 get_files_dirs(merge);
1167 entries = get_unmerged();
1168 re_head = get_renames(head, common, head, merge, entries);
1169 re_merge = get_renames(merge, common, head, merge, entries);
1170 clean = process_renames(re_head, re_merge,
1171 branch1, branch2);
1172 for (i = 0; i < entries->nr; i++) {
1173 const char *path = entries->items[i].path;
1174 struct stage_data *e = entries->items[i].util;
1175 if (e->processed)
1176 continue;
1177 if (!process_entry(path, e, branch1, branch2))
1178 clean = 0;
1179 }
1181 path_list_clear(re_merge, 0);
1182 path_list_clear(re_head, 0);
1183 path_list_clear(entries, 1);
1185 if (clean || index_only)
1186 *result = git_write_tree();
1187 else
1188 *result = NULL;
1189 } else {
1190 clean = 1;
1191 printf("merging of trees %s and %s resulted in %s\n",
1192 sha1_to_hex(head->object.sha1),
1193 sha1_to_hex(merge->object.sha1),
1194 sha1_to_hex((*result)->object.sha1));
1195 }
1197 return clean;
1198 }
1200 /*
1201 * Merge the commits h1 and h2, return the resulting virtual
1202 * commit object and a flag indicating the cleaness of the merge.
1203 */
1204 static
1205 int merge(struct commit *h1,
1206 struct commit *h2,
1207 const char *branch1,
1208 const char *branch2,
1209 int call_depth /* =0 */,
1210 struct commit *ancestor /* =None */,
1211 struct commit **result)
1212 {
1213 struct commit_list *ca = NULL, *iter;
1214 struct commit *merged_common_ancestors;
1215 struct tree *mrtree;
1216 int clean;
1218 output("Merging:");
1219 output_commit_title(h1);
1220 output_commit_title(h2);
1222 if (ancestor)
1223 commit_list_insert(ancestor, &ca);
1224 else
1225 ca = get_merge_bases(h1, h2, 1);
1227 output("found %u common ancestor(s):", commit_list_count(ca));
1228 for (iter = ca; iter; iter = iter->next)
1229 output_commit_title(iter->item);
1231 merged_common_ancestors = pop_commit(&ca);
1233 for (iter = ca; iter; iter = iter->next) {
1234 output_indent = call_depth + 1;
1235 /*
1236 * When the merge fails, the result contains files
1237 * with conflict markers. The cleanness flag is
1238 * ignored, it was never acutally used, as result of
1239 * merge_trees has always overwritten it: the commited
1240 * "conflicts" were already resolved.
1241 */
1242 merge(merged_common_ancestors, iter->item,
1243 "Temporary merge branch 1",
1244 "Temporary merge branch 2",
1245 call_depth + 1,
1246 NULL,
1247 &merged_common_ancestors);
1248 output_indent = call_depth;
1250 if (!merged_common_ancestors)
1251 die("merge returned no commit");
1252 }
1254 if (call_depth == 0) {
1255 setup_index(0 /* $GIT_DIR/index */);
1256 index_only = 0;
1257 } else {
1258 setup_index(1 /* temporary index */);
1259 git_read_tree(h1->tree);
1260 index_only = 1;
1261 }
1263 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1264 branch1, branch2, &mrtree);
1266 if (!ancestor && (clean || index_only)) {
1267 *result = make_virtual_commit(mrtree, "merged tree");
1268 commit_list_insert(h1, &(*result)->parents);
1269 commit_list_insert(h2, &(*result)->parents->next);
1270 } else
1271 *result = NULL;
1273 return clean;
1274 }
1276 static struct commit *get_ref(const char *ref)
1277 {
1278 unsigned char sha1[20];
1279 struct object *object;
1281 if (get_sha1(ref, sha1))
1282 die("Could not resolve ref '%s'", ref);
1283 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1284 if (object->type != OBJ_COMMIT)
1285 return NULL;
1286 if (parse_commit((struct commit *)object))
1287 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1288 return (struct commit *)object;
1289 }
1291 int main(int argc, char *argv[])
1292 {
1293 static const char *bases[2];
1294 static unsigned bases_count = 0;
1295 int i, clean;
1296 const char *branch1, *branch2;
1297 struct commit *result, *h1, *h2;
1299 original_index_file = getenv("GIT_INDEX_FILE");
1301 if (!original_index_file)
1302 original_index_file = strdup(git_path("index"));
1304 temporary_index_file = strdup(git_path("mrg-rcrsv-tmp-idx"));
1306 if (argc < 4)
1307 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1309 for (i = 1; i < argc; ++i) {
1310 if (!strcmp(argv[i], "--"))
1311 break;
1312 if (bases_count < sizeof(bases)/sizeof(*bases))
1313 bases[bases_count++] = argv[i];
1314 }
1315 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1316 die("Not handling anything other than two heads merge.");
1318 branch1 = argv[++i];
1319 branch2 = argv[++i];
1320 printf("Merging %s with %s\n", branch1, branch2);
1322 h1 = get_ref(branch1);
1323 h2 = get_ref(branch2);
1325 if (bases_count == 1) {
1326 struct commit *ancestor = get_ref(bases[0]);
1327 clean = merge(h1, h2, branch1, branch2, 0, ancestor, &result);
1328 } else
1329 clean = merge(h1, h2, branch1, branch2, 0, NULL, &result);
1331 if (cache_dirty)
1332 flush_cache();
1334 return clean ? 0: 1;
1335 }
1337 /*
1338 vim: sw=8 noet
1339 */