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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"
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 return commit;
47 }
49 /*
50 * TODO: we should not have to copy the SHA1s around, but rather reference
51 * them. That way, sha_eq() is just sha1 == sha2.
52 */
53 static int sha_eq(const unsigned char *a, const unsigned char *b)
54 {
55 if (!a && !b)
56 return 2;
57 return a && b && memcmp(a, b, 20) == 0;
58 }
60 /*
61 * TODO: check if we can just reuse the active_cache structure: it is already
62 * sorted (by name, stage).
63 * Only problem: do not write it when flushing the cache.
64 */
65 struct stage_data
66 {
67 struct
68 {
69 unsigned mode;
70 unsigned char sha[20];
71 } stages[4];
72 unsigned processed:1;
73 };
75 static struct path_list current_file_set = {NULL, 0, 0, 1};
76 static struct path_list current_directory_set = {NULL, 0, 0, 1};
78 static int output_indent = 0;
80 static void output(const char *fmt, ...)
81 {
82 va_list args;
83 int i;
84 for (i = output_indent; i--;)
85 fputs(" ", stdout);
86 va_start(args, fmt);
87 vfprintf(stdout, fmt, args);
88 va_end(args);
89 fputc('\n', stdout);
90 }
92 static void output_commit_title(struct commit *commit)
93 {
94 int i;
95 for (i = output_indent; i--;)
96 fputs(" ", stdout);
97 if (commit->util)
98 printf("virtual %s\n", (char *)commit->util);
99 else {
100 printf("%s ", sha1_to_hex(commit->object.sha1));
101 if (parse_commit(commit) != 0)
102 printf("(bad commit)\n");
103 else {
104 const char *s;
105 int len;
106 for (s = commit->buffer; *s; s++)
107 if (*s == '\n' && s[1] == '\n') {
108 s += 2;
109 break;
110 }
111 for (len = 0; s[len] && '\n' != s[len]; len++)
112 ; /* do nothing */
113 printf("%.*s\n", len, s);
114 }
115 }
116 }
118 static const char *original_index_file;
119 static const char *temporary_index_file;
120 static int cache_dirty = 0;
122 static int flush_cache(void)
123 {
124 /* flush temporary index */
125 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
126 int fd = hold_lock_file_for_update(lock, getenv("GIT_INDEX_FILE"));
127 if (fd < 0)
128 die("could not lock %s", temporary_index_file);
129 if (write_cache(fd, active_cache, active_nr) ||
130 close(fd) || commit_lock_file(lock))
131 die ("unable to write %s", getenv("GIT_INDEX_FILE"));
132 discard_cache();
133 cache_dirty = 0;
134 return 0;
135 }
137 static void setup_index(int temp)
138 {
139 const char *idx = temp ? temporary_index_file: original_index_file;
140 if (cache_dirty)
141 die("fatal: cache changed flush_cache();");
142 unlink(temporary_index_file);
143 setenv("GIT_INDEX_FILE", idx, 1);
144 discard_cache();
145 }
147 static struct cache_entry *make_cache_entry(unsigned int mode,
148 const unsigned char *sha1, const char *path, int stage, int refresh)
149 {
150 int size, len;
151 struct cache_entry *ce;
153 if (!verify_path(path))
154 return NULL;
156 len = strlen(path);
157 size = cache_entry_size(len);
158 ce = xcalloc(1, size);
160 memcpy(ce->sha1, sha1, 20);
161 memcpy(ce->name, path, len);
162 ce->ce_flags = create_ce_flags(len, stage);
163 ce->ce_mode = create_ce_mode(mode);
165 if (refresh)
166 return refresh_cache_entry(ce, 0);
168 return ce;
169 }
171 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
172 const char *path, int stage, int refresh, int options)
173 {
174 struct cache_entry *ce;
175 if (!cache_dirty)
176 read_cache_from(getenv("GIT_INDEX_FILE"));
177 cache_dirty++;
178 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
179 if (!ce)
180 return error("cache_addinfo failed: %s", strerror(cache_errno));
181 return add_cache_entry(ce, options);
182 }
184 /*
185 * This is a global variable which is used in a number of places but
186 * only written to in the 'merge' function.
187 *
188 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
189 * don't update the working directory.
190 * 0 => Leave unmerged entries in the cache and update
191 * the working directory.
192 */
193 static int index_only = 0;
195 /*
196 * TODO: this can be streamlined by refactoring builtin-read-tree.c
197 */
198 static int git_read_tree(const struct tree *tree)
199 {
200 int rc;
201 const char *argv[] = { "git-read-tree", NULL, NULL, };
202 if (cache_dirty)
203 die("read-tree with dirty cache");
204 argv[1] = sha1_to_hex(tree->object.sha1);
205 rc = run_command_v(2, argv);
206 return rc < 0 ? -1: rc;
207 }
209 /*
210 * TODO: this can be streamlined by refactoring builtin-read-tree.c
211 */
212 static int git_merge_trees(const char *update_arg,
213 struct tree *common,
214 struct tree *head,
215 struct tree *merge)
216 {
217 int rc;
218 const char *argv[] = {
219 "git-read-tree", NULL, "-m", NULL, NULL, NULL,
220 NULL,
221 };
222 if (cache_dirty)
223 flush_cache();
224 argv[1] = update_arg;
225 argv[3] = sha1_to_hex(common->object.sha1);
226 argv[4] = sha1_to_hex(head->object.sha1);
227 argv[5] = sha1_to_hex(merge->object.sha1);
228 rc = run_command_v(6, argv);
229 return rc < 0 ? -1: rc;
230 }
232 /*
233 * TODO: this can be streamlined by refactoring builtin-write-tree.c
234 */
235 static struct tree *git_write_tree(void)
236 {
237 FILE *fp;
238 int rc;
239 char buf[41];
240 unsigned char sha1[20];
241 int ch;
242 unsigned i = 0;
243 if (cache_dirty)
244 flush_cache();
245 fp = popen("git-write-tree 2>/dev/null", "r");
246 while ((ch = fgetc(fp)) != EOF)
247 if (i < sizeof(buf)-1 && ch >= '0' && ch <= 'f')
248 buf[i++] = ch;
249 else
250 break;
251 rc = pclose(fp);
252 if (rc == -1 || WEXITSTATUS(rc))
253 return NULL;
254 buf[i] = '\0';
255 if (get_sha1(buf, sha1) != 0)
256 return NULL;
257 return lookup_tree(sha1);
258 }
260 static int save_files_dirs(const unsigned char *sha1,
261 const char *base, int baselen, const char *path,
262 unsigned int mode, int stage)
263 {
264 int len = strlen(path);
265 char *newpath = malloc(baselen + len + 1);
266 memcpy(newpath, base, baselen);
267 memcpy(newpath + baselen, path, len);
268 newpath[baselen + len] = '\0';
270 if (S_ISDIR(mode))
271 path_list_insert(newpath, ¤t_directory_set);
272 else
273 path_list_insert(newpath, ¤t_file_set);
274 free(newpath);
276 return READ_TREE_RECURSIVE;
277 }
279 static int get_files_dirs(struct tree *tree)
280 {
281 int n;
282 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
283 return 0;
284 n = current_file_set.nr + current_directory_set.nr;
285 return n;
286 }
288 /*
289 * Returns a index_entry instance which doesn't have to correspond to
290 * a real cache entry in Git's index.
291 */
292 static struct stage_data *insert_stage_data(const char *path,
293 struct tree *o, struct tree *a, struct tree *b,
294 struct path_list *entries)
295 {
296 struct path_list_item *item;
297 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
298 get_tree_entry(o->object.sha1, path,
299 e->stages[1].sha, &e->stages[1].mode);
300 get_tree_entry(a->object.sha1, path,
301 e->stages[2].sha, &e->stages[2].mode);
302 get_tree_entry(b->object.sha1, path,
303 e->stages[3].sha, &e->stages[3].mode);
304 item = path_list_insert(path, entries);
305 item->util = e;
306 return e;
307 }
309 /*
310 * Create a dictionary mapping file names to stage_data objects. The
311 * dictionary contains one entry for every path with a non-zero stage entry.
312 */
313 static struct path_list *get_unmerged(void)
314 {
315 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
316 int i;
318 unmerged->strdup_paths = 1;
319 if (!cache_dirty) {
320 read_cache_from(getenv("GIT_INDEX_FILE"));
321 cache_dirty++;
322 }
323 for (i = 0; i < active_nr; i++) {
324 struct path_list_item *item;
325 struct stage_data *e;
326 struct cache_entry *ce = active_cache[i];
327 if (!ce_stage(ce))
328 continue;
330 item = path_list_lookup(ce->name, unmerged);
331 if (!item) {
332 item = path_list_insert(ce->name, unmerged);
333 item->util = xcalloc(1, sizeof(struct stage_data));
334 }
335 e = item->util;
336 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
337 memcpy(e->stages[ce_stage(ce)].sha, ce->sha1, 20);
338 }
340 return unmerged;
341 }
343 struct rename
344 {
345 struct diff_filepair *pair;
346 struct stage_data *src_entry;
347 struct stage_data *dst_entry;
348 unsigned processed:1;
349 };
351 /*
352 * Get information of all renames which occured between 'o_tree' and
353 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
354 * 'b_tree') to be able to associate the correct cache entries with
355 * the rename information. 'tree' is always equal to either a_tree or b_tree.
356 */
357 static struct path_list *get_renames(struct tree *tree,
358 struct tree *o_tree,
359 struct tree *a_tree,
360 struct tree *b_tree,
361 struct path_list *entries)
362 {
363 int i;
364 struct path_list *renames;
365 struct diff_options opts;
367 renames = xcalloc(1, sizeof(struct path_list));
368 diff_setup(&opts);
369 opts.recursive = 1;
370 opts.detect_rename = DIFF_DETECT_RENAME;
371 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
372 if (diff_setup_done(&opts) < 0)
373 die("diff setup failed");
374 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
375 diffcore_std(&opts);
376 for (i = 0; i < diff_queued_diff.nr; ++i) {
377 struct path_list_item *item;
378 struct rename *re;
379 struct diff_filepair *pair = diff_queued_diff.queue[i];
380 if (pair->status != 'R') {
381 diff_free_filepair(pair);
382 continue;
383 }
384 re = xmalloc(sizeof(*re));
385 re->processed = 0;
386 re->pair = pair;
387 item = path_list_lookup(re->pair->one->path, entries);
388 if (!item)
389 re->src_entry = insert_stage_data(re->pair->one->path,
390 o_tree, a_tree, b_tree, entries);
391 else
392 re->src_entry = item->util;
394 item = path_list_lookup(re->pair->two->path, entries);
395 if (!item)
396 re->dst_entry = insert_stage_data(re->pair->two->path,
397 o_tree, a_tree, b_tree, entries);
398 else
399 re->dst_entry = item->util;
400 item = path_list_insert(pair->one->path, renames);
401 item->util = re;
402 }
403 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
404 diff_queued_diff.nr = 0;
405 diff_flush(&opts);
406 return renames;
407 }
409 int update_stages(const char *path, struct diff_filespec *o,
410 struct diff_filespec *a, struct diff_filespec *b, int clear)
411 {
412 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
413 if (clear)
414 if (remove_file_from_cache(path))
415 return -1;
416 if (o)
417 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
418 return -1;
419 if (a)
420 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
421 return -1;
422 if (b)
423 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
424 return -1;
425 return 0;
426 }
428 static int remove_path(const char *name)
429 {
430 int ret, len;
431 char *slash, *dirs;
433 ret = unlink(name);
434 if (ret)
435 return ret;
436 len = strlen(name);
437 dirs = malloc(len+1);
438 memcpy(dirs, name, len);
439 dirs[len] = '\0';
440 while ((slash = strrchr(name, '/'))) {
441 *slash = '\0';
442 len = slash - name;
443 if (rmdir(name) != 0)
444 break;
445 }
446 free(dirs);
447 return ret;
448 }
450 /*
451 * TODO: once we no longer call external programs, we'd probably be better off
452 * not setting / getting the environment variable GIT_INDEX_FILE all the time.
453 */
454 int remove_file(int clean, const char *path)
455 {
456 int update_cache = index_only || clean;
457 int update_working_directory = !index_only;
459 if (update_cache) {
460 if (!cache_dirty)
461 read_cache_from(getenv("GIT_INDEX_FILE"));
462 cache_dirty++;
463 if (remove_file_from_cache(path))
464 return -1;
465 }
466 if (update_working_directory)
467 {
468 unlink(path);
469 if (errno != ENOENT || errno != EISDIR)
470 return -1;
471 remove_path(path);
472 }
473 return 0;
474 }
476 static char *unique_path(const char *path, const char *branch)
477 {
478 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
479 int suffix = 0;
480 struct stat st;
481 char *p = newpath + strlen(newpath);
482 strcpy(newpath, path);
483 strcat(newpath, "~");
484 strcpy(p, branch);
485 for (; *p; ++p)
486 if ('/' == *p)
487 *p = '_';
488 while (path_list_has_path(¤t_file_set, newpath) ||
489 path_list_has_path(¤t_directory_set, newpath) ||
490 lstat(newpath, &st) == 0)
491 sprintf(p, "_%d", suffix++);
493 path_list_insert(newpath, ¤t_file_set);
494 return newpath;
495 }
497 static int mkdir_p(const char *path, unsigned long mode)
498 {
499 /* path points to cache entries, so strdup before messing with it */
500 char *buf = strdup(path);
501 int result = safe_create_leading_directories(buf);
502 free(buf);
503 return result;
504 }
506 static void flush_buffer(int fd, const char *buf, unsigned long size)
507 {
508 while (size > 0) {
509 long ret = xwrite(fd, buf, size);
510 if (ret < 0) {
511 /* Ignore epipe */
512 if (errno == EPIPE)
513 break;
514 die("merge-recursive: %s", strerror(errno));
515 } else if (!ret) {
516 die("merge-recursive: disk full?");
517 }
518 size -= ret;
519 buf += ret;
520 }
521 }
523 void update_file_flags(const unsigned char *sha,
524 unsigned mode,
525 const char *path,
526 int update_cache,
527 int update_wd)
528 {
529 if (index_only)
530 update_wd = 0;
532 if (update_wd) {
533 char type[20];
534 void *buf;
535 unsigned long size;
537 buf = read_sha1_file(sha, type, &size);
538 if (!buf)
539 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
540 if (strcmp(type, blob_type) != 0)
541 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
543 if (S_ISREG(mode)) {
544 int fd;
545 if (mkdir_p(path, 0777))
546 die("failed to create path %s: %s", path, strerror(errno));
547 unlink(path);
548 if (mode & 0100)
549 mode = 0777;
550 else
551 mode = 0666;
552 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
553 if (fd < 0)
554 die("failed to open %s: %s", path, strerror(errno));
555 flush_buffer(fd, buf, size);
556 close(fd);
557 } else if (S_ISLNK(mode)) {
558 char *lnk = malloc(size + 1);
559 memcpy(lnk, buf, size);
560 lnk[size] = '\0';
561 mkdir_p(path, 0777);
562 unlink(lnk);
563 symlink(lnk, path);
564 } else
565 die("do not know what to do with %06o %s '%s'",
566 mode, sha1_to_hex(sha), path);
567 }
568 if (update_cache)
569 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
570 }
572 void update_file(int clean,
573 const unsigned char *sha,
574 unsigned mode,
575 const char *path)
576 {
577 update_file_flags(sha, mode, path, index_only || clean, !index_only);
578 }
580 /* Low level file merging, update and removal */
582 struct merge_file_info
583 {
584 unsigned char sha[20];
585 unsigned mode;
586 unsigned clean:1,
587 merge:1;
588 };
590 static char *git_unpack_file(const unsigned char *sha1, char *path)
591 {
592 void *buf;
593 char type[20];
594 unsigned long size;
595 int fd;
597 buf = read_sha1_file(sha1, type, &size);
598 if (!buf || strcmp(type, blob_type))
599 die("unable to read blob object %s", sha1_to_hex(sha1));
601 strcpy(path, ".merge_file_XXXXXX");
602 fd = mkstemp(path);
603 if (fd < 0)
604 die("unable to create temp-file");
605 flush_buffer(fd, buf, size);
606 close(fd);
607 return path;
608 }
610 static struct merge_file_info merge_file(struct diff_filespec *o,
611 struct diff_filespec *a, struct diff_filespec *b,
612 const char *branch1Name, const char *branch2Name)
613 {
614 struct merge_file_info result;
615 result.merge = 0;
616 result.clean = 1;
618 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
619 result.clean = 0;
620 if (S_ISREG(a->mode)) {
621 result.mode = a->mode;
622 memcpy(result.sha, a->sha1, 20);
623 } else {
624 result.mode = b->mode;
625 memcpy(result.sha, b->sha1, 20);
626 }
627 } else {
628 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
629 result.merge = 1;
631 result.mode = a->mode == o->mode ? b->mode: a->mode;
633 if (sha_eq(a->sha1, o->sha1))
634 memcpy(result.sha, b->sha1, 20);
635 else if (sha_eq(b->sha1, o->sha1))
636 memcpy(result.sha, a->sha1, 20);
637 else if (S_ISREG(a->mode)) {
638 int code = 1, fd;
639 struct stat st;
640 char orig[PATH_MAX];
641 char src1[PATH_MAX];
642 char src2[PATH_MAX];
643 const char *argv[] = {
644 "merge", "-L", NULL, "-L", NULL, "-L", NULL,
645 src1, orig, src2,
646 NULL
647 };
648 char *la, *lb, *lo;
650 git_unpack_file(o->sha1, orig);
651 git_unpack_file(a->sha1, src1);
652 git_unpack_file(b->sha1, src2);
654 argv[2] = la = strdup(mkpath("%s/%s", branch1Name, a->path));
655 argv[6] = lb = strdup(mkpath("%s/%s", branch2Name, b->path));
656 argv[4] = lo = strdup(mkpath("orig/%s", o->path));
658 code = run_command_v(10, argv);
660 free(la);
661 free(lb);
662 free(lo);
663 if (code && code < -256) {
664 die("Failed to execute 'merge'. merge(1) is used as the "
665 "file-level merge tool. Is 'merge' in your path?");
666 }
667 fd = open(src1, O_RDONLY);
668 if (fd < 0 || fstat(fd, &st) < 0 ||
669 index_fd(result.sha, fd, &st, 1,
670 "blob"))
671 die("Unable to add %s to database", src1);
673 unlink(orig);
674 unlink(src1);
675 unlink(src2);
677 result.clean = WEXITSTATUS(code) == 0;
678 } else {
679 if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
680 die("cannot merge modes?");
682 memcpy(result.sha, a->sha1, 20);
684 if (!sha_eq(a->sha1, b->sha1))
685 result.clean = 0;
686 }
687 }
689 return result;
690 }
692 static void conflict_rename_rename(struct rename *ren1,
693 const char *branch1,
694 struct rename *ren2,
695 const char *branch2)
696 {
697 char *del[2];
698 int delp = 0;
699 const char *ren1_dst = ren1->pair->two->path;
700 const char *ren2_dst = ren2->pair->two->path;
701 const char *dst_name1 = ren1_dst;
702 const char *dst_name2 = ren2_dst;
703 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
704 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
705 output("%s is a directory in %s adding as %s instead",
706 ren1_dst, branch2, dst_name1);
707 remove_file(0, ren1_dst);
708 }
709 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
710 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
711 output("%s is a directory in %s adding as %s instead",
712 ren2_dst, branch1, dst_name2);
713 remove_file(0, ren2_dst);
714 }
715 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
716 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
717 while (delp--)
718 free(del[delp]);
719 }
721 static void conflict_rename_dir(struct rename *ren1,
722 const char *branch1)
723 {
724 char *new_path = unique_path(ren1->pair->two->path, branch1);
725 output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
726 remove_file(0, ren1->pair->two->path);
727 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
728 free(new_path);
729 }
731 static void conflict_rename_rename_2(struct rename *ren1,
732 const char *branch1,
733 struct rename *ren2,
734 const char *branch2)
735 {
736 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
737 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
738 output("Renaming %s to %s and %s to %s instead",
739 ren1->pair->one->path, new_path1,
740 ren2->pair->one->path, new_path2);
741 remove_file(0, ren1->pair->two->path);
742 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
743 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
744 free(new_path2);
745 free(new_path1);
746 }
748 static int process_renames(struct path_list *a_renames,
749 struct path_list *b_renames,
750 const char *a_branch,
751 const char *b_branch)
752 {
753 int clean_merge = 1, i, j;
754 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
755 const struct rename *sre;
757 for (i = 0; i < a_renames->nr; i++) {
758 sre = a_renames->items[i].util;
759 path_list_insert(sre->pair->two->path, &a_by_dst)->util
760 = sre->dst_entry;
761 }
762 for (i = 0; i < b_renames->nr; i++) {
763 sre = b_renames->items[i].util;
764 path_list_insert(sre->pair->two->path, &b_by_dst)->util
765 = sre->dst_entry;
766 }
768 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
769 int compare;
770 char *src;
771 struct path_list *renames1, *renames2, *renames2Dst;
772 struct rename *ren1 = NULL, *ren2 = NULL;
773 const char *branch1, *branch2;
774 const char *ren1_src, *ren1_dst;
776 if (i >= a_renames->nr) {
777 compare = 1;
778 ren2 = b_renames->items[j++].util;
779 } else if (j >= b_renames->nr) {
780 compare = -1;
781 ren1 = a_renames->items[i++].util;
782 } else {
783 compare = strcmp(a_renames->items[i].path,
784 b_renames->items[j].path);
785 ren1 = a_renames->items[i++].util;
786 ren2 = b_renames->items[j++].util;
787 }
789 /* TODO: refactor, so that 1/2 are not needed */
790 if (ren1) {
791 renames1 = a_renames;
792 renames2 = b_renames;
793 renames2Dst = &b_by_dst;
794 branch1 = a_branch;
795 branch2 = b_branch;
796 } else {
797 struct rename *tmp;
798 renames1 = b_renames;
799 renames2 = a_renames;
800 renames2Dst = &a_by_dst;
801 branch1 = b_branch;
802 branch2 = a_branch;
803 tmp = ren2;
804 ren2 = ren1;
805 ren1 = tmp;
806 }
807 src = ren1->pair->one->path;
809 ren1->dst_entry->processed = 1;
810 ren1->src_entry->processed = 1;
812 if (ren1->processed)
813 continue;
814 ren1->processed = 1;
816 ren1_src = ren1->pair->one->path;
817 ren1_dst = ren1->pair->two->path;
819 if (ren2) {
820 const char *ren2_src = ren2->pair->one->path;
821 const char *ren2_dst = ren2->pair->two->path;
822 /* Renamed in 1 and renamed in 2 */
823 if (strcmp(ren1_src, ren2_src) != 0)
824 die("ren1.src != ren2.src");
825 ren2->dst_entry->processed = 1;
826 ren2->processed = 1;
827 if (strcmp(ren1_dst, ren2_dst) != 0) {
828 clean_merge = 0;
829 output("CONFLICT (rename/rename): "
830 "Rename %s->%s in branch %s "
831 "rename %s->%s in %s",
832 src, ren1_dst, branch1,
833 src, ren2_dst, branch2);
834 conflict_rename_rename(ren1, branch1, ren2, branch2);
835 } else {
836 struct merge_file_info mfi;
837 remove_file(1, ren1_src);
838 mfi = merge_file(ren1->pair->one,
839 ren1->pair->two,
840 ren2->pair->two,
841 branch1,
842 branch2);
843 if (mfi.merge || !mfi.clean)
844 output("Renaming %s->%s", src, ren1_dst);
846 if (mfi.merge)
847 output("Auto-merging %s", ren1_dst);
849 if (!mfi.clean) {
850 output("CONFLICT (content): merge conflict in %s",
851 ren1_dst);
852 clean_merge = 0;
854 if (!index_only)
855 update_stages(ren1_dst,
856 ren1->pair->one,
857 ren1->pair->two,
858 ren2->pair->two,
859 1 /* clear */);
860 }
861 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
862 }
863 } else {
864 /* Renamed in 1, maybe changed in 2 */
865 struct path_list_item *item;
866 /* we only use sha1 and mode of these */
867 struct diff_filespec src_other, dst_other;
868 int try_merge, stage = a_renames == renames1 ? 3: 2;
870 remove_file(1, ren1_src);
872 memcpy(src_other.sha1,
873 ren1->src_entry->stages[stage].sha, 20);
874 src_other.mode = ren1->src_entry->stages[stage].mode;
875 memcpy(dst_other.sha1,
876 ren1->dst_entry->stages[stage].sha, 20);
877 dst_other.mode = ren1->dst_entry->stages[stage].mode;
879 try_merge = 0;
881 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
882 clean_merge = 0;
883 output("CONFLICT (rename/directory): Rename %s->%s in %s "
884 " directory %s added in %s",
885 ren1_src, ren1_dst, branch1,
886 ren1_dst, branch2);
887 conflict_rename_dir(ren1, branch1);
888 } else if (sha_eq(src_other.sha1, null_sha1)) {
889 clean_merge = 0;
890 output("CONFLICT (rename/delete): Rename %s->%s in %s "
891 "and deleted in %s",
892 ren1_src, ren1_dst, branch1,
893 branch2);
894 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
895 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
896 const char *new_path;
897 clean_merge = 0;
898 try_merge = 1;
899 output("CONFLICT (rename/add): Rename %s->%s in %s. "
900 "%s added in %s",
901 ren1_src, ren1_dst, branch1,
902 ren1_dst, branch2);
903 new_path = unique_path(ren1_dst, branch2);
904 output("Adding as %s instead", new_path);
905 update_file(0, dst_other.sha1, dst_other.mode, new_path);
906 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
907 ren2 = item->util;
908 clean_merge = 0;
909 ren2->processed = 1;
910 output("CONFLICT (rename/rename): Rename %s->%s in %s. "
911 "Rename %s->%s in %s",
912 ren1_src, ren1_dst, branch1,
913 ren2->pair->one->path, ren2->pair->two->path, branch2);
914 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
915 } else
916 try_merge = 1;
918 if (try_merge) {
919 struct diff_filespec *o, *a, *b;
920 struct merge_file_info mfi;
921 src_other.path = (char *)ren1_src;
923 o = ren1->pair->one;
924 if (a_renames == renames1) {
925 a = ren1->pair->two;
926 b = &src_other;
927 } else {
928 b = ren1->pair->two;
929 a = &src_other;
930 }
931 mfi = merge_file(o, a, b,
932 a_branch, b_branch);
934 if (mfi.merge || !mfi.clean)
935 output("Renaming %s => %s", ren1_src, ren1_dst);
936 if (mfi.merge)
937 output("Auto-merging %s", ren1_dst);
938 if (!mfi.clean) {
939 output("CONFLICT (rename/modify): Merge conflict in %s",
940 ren1_dst);
941 clean_merge = 0;
943 if (!index_only)
944 update_stages(ren1_dst,
945 o, a, b, 1);
946 }
947 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
948 }
949 }
950 }
951 path_list_clear(&a_by_dst, 0);
952 path_list_clear(&b_by_dst, 0);
954 if (cache_dirty)
955 flush_cache();
956 return clean_merge;
957 }
959 static unsigned char *has_sha(const unsigned char *sha)
960 {
961 return memcmp(sha, null_sha1, 20) == 0 ? NULL: (unsigned char *)sha;
962 }
964 /* Per entry merge function */
965 static int process_entry(const char *path, struct stage_data *entry,
966 const char *branch1Name,
967 const char *branch2Name)
968 {
969 /*
970 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
971 print_index_entry("\tpath: ", entry);
972 */
973 int clean_merge = 1;
974 unsigned char *o_sha = has_sha(entry->stages[1].sha);
975 unsigned char *a_sha = has_sha(entry->stages[2].sha);
976 unsigned char *b_sha = has_sha(entry->stages[3].sha);
977 unsigned o_mode = entry->stages[1].mode;
978 unsigned a_mode = entry->stages[2].mode;
979 unsigned b_mode = entry->stages[3].mode;
981 if (o_sha && (!a_sha || !b_sha)) {
982 /* Case A: Deleted in one */
983 if ((!a_sha && !b_sha) ||
984 (sha_eq(a_sha, o_sha) && !b_sha) ||
985 (!a_sha && sha_eq(b_sha, o_sha))) {
986 /* Deleted in both or deleted in one and
987 * unchanged in the other */
988 if (a_sha)
989 output("Removing %s", path);
990 remove_file(1, path);
991 } else {
992 /* Deleted in one and changed in the other */
993 clean_merge = 0;
994 if (!a_sha) {
995 output("CONFLICT (delete/modify): %s deleted in %s "
996 "and modified in %s. Version %s of %s left in tree.",
997 path, branch1Name,
998 branch2Name, branch2Name, path);
999 update_file(0, b_sha, b_mode, path);
1000 } else {
1001 output("CONFLICT (delete/modify): %s deleted in %s "
1002 "and modified in %s. Version %s of %s left in tree.",
1003 path, branch2Name,
1004 branch1Name, branch1Name, path);
1005 update_file(0, a_sha, a_mode, path);
1006 }
1007 }
1009 } else if ((!o_sha && a_sha && !b_sha) ||
1010 (!o_sha && !a_sha && b_sha)) {
1011 /* Case B: Added in one. */
1012 const char *add_branch;
1013 const char *other_branch;
1014 unsigned mode;
1015 const unsigned char *sha;
1016 const char *conf;
1018 if (a_sha) {
1019 add_branch = branch1Name;
1020 other_branch = branch2Name;
1021 mode = a_mode;
1022 sha = a_sha;
1023 conf = "file/directory";
1024 } else {
1025 add_branch = branch2Name;
1026 other_branch = branch1Name;
1027 mode = b_mode;
1028 sha = b_sha;
1029 conf = "directory/file";
1030 }
1031 if (path_list_has_path(¤t_directory_set, path)) {
1032 const char *new_path = unique_path(path, add_branch);
1033 clean_merge = 0;
1034 output("CONFLICT (%s): There is a directory with name %s in %s. "
1035 "Adding %s as %s",
1036 conf, path, other_branch, path, new_path);
1037 remove_file(0, path);
1038 update_file(0, sha, mode, new_path);
1039 } else {
1040 output("Adding %s", path);
1041 update_file(1, sha, mode, path);
1042 }
1043 } else if (!o_sha && a_sha && b_sha) {
1044 /* Case C: Added in both (check for same permissions). */
1045 if (sha_eq(a_sha, b_sha)) {
1046 if (a_mode != b_mode) {
1047 clean_merge = 0;
1048 output("CONFLICT: File %s added identically in both branches, "
1049 "but permissions conflict %06o->%06o",
1050 path, a_mode, b_mode);
1051 output("CONFLICT: adding with permission: %06o", a_mode);
1052 update_file(0, a_sha, a_mode, path);
1053 } else {
1054 /* This case is handled by git-read-tree */
1055 assert(0 && "This case must be handled by git-read-tree");
1056 }
1057 } else {
1058 const char *new_path1, *new_path2;
1059 clean_merge = 0;
1060 new_path1 = unique_path(path, branch1Name);
1061 new_path2 = unique_path(path, branch2Name);
1062 output("CONFLICT (add/add): File %s added non-identically "
1063 "in both branches. Adding as %s and %s instead.",
1064 path, new_path1, new_path2);
1065 remove_file(0, path);
1066 update_file(0, a_sha, a_mode, new_path1);
1067 update_file(0, b_sha, b_mode, new_path2);
1068 }
1070 } else if (o_sha && a_sha && b_sha) {
1071 /* case D: Modified in both, but differently. */
1072 struct merge_file_info mfi;
1073 struct diff_filespec o, a, b;
1075 output("Auto-merging %s", path);
1076 o.path = a.path = b.path = (char *)path;
1077 memcpy(o.sha1, o_sha, 20);
1078 o.mode = o_mode;
1079 memcpy(a.sha1, a_sha, 20);
1080 a.mode = a_mode;
1081 memcpy(b.sha1, b_sha, 20);
1082 b.mode = b_mode;
1084 mfi = merge_file(&o, &a, &b,
1085 branch1Name, branch2Name);
1087 if (mfi.clean)
1088 update_file(1, mfi.sha, mfi.mode, path);
1089 else {
1090 clean_merge = 0;
1091 output("CONFLICT (content): Merge conflict in %s", path);
1093 if (index_only)
1094 update_file(0, mfi.sha, mfi.mode, path);
1095 else
1096 update_file_flags(mfi.sha, mfi.mode, path,
1097 0 /* update_cache */, 1 /* update_working_directory */);
1098 }
1099 } else
1100 die("Fatal merge failure, shouldn't happen.");
1102 if (cache_dirty)
1103 flush_cache();
1105 return clean_merge;
1106 }
1108 static int merge_trees(struct tree *head,
1109 struct tree *merge,
1110 struct tree *common,
1111 const char *branch1Name,
1112 const char *branch2Name,
1113 struct tree **result)
1114 {
1115 int code, clean;
1116 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1117 output("Already uptodate!");
1118 *result = head;
1119 return 1;
1120 }
1122 code = git_merge_trees(index_only ? "-i": "-u", common, head, merge);
1124 if (code != 0)
1125 die("merging of trees %s and %s failed",
1126 sha1_to_hex(head->object.sha1),
1127 sha1_to_hex(merge->object.sha1));
1129 *result = git_write_tree();
1131 if (!*result) {
1132 struct path_list *entries, *re_head, *re_merge;
1133 int i;
1134 path_list_clear(¤t_file_set, 1);
1135 path_list_clear(¤t_directory_set, 1);
1136 get_files_dirs(head);
1137 get_files_dirs(merge);
1139 entries = get_unmerged();
1140 re_head = get_renames(head, common, head, merge, entries);
1141 re_merge = get_renames(merge, common, head, merge, entries);
1142 clean = process_renames(re_head, re_merge,
1143 branch1Name, branch2Name);
1144 for (i = 0; i < entries->nr; i++) {
1145 const char *path = entries->items[i].path;
1146 struct stage_data *e = entries->items[i].util;
1147 if (e->processed)
1148 continue;
1149 if (!process_entry(path, e, branch1Name, branch2Name))
1150 clean = 0;
1151 }
1153 path_list_clear(re_merge, 0);
1154 path_list_clear(re_head, 0);
1155 path_list_clear(entries, 1);
1157 if (clean || index_only)
1158 *result = git_write_tree();
1159 else
1160 *result = NULL;
1161 } else {
1162 clean = 1;
1163 printf("merging of trees %s and %s resulted in %s\n",
1164 sha1_to_hex(head->object.sha1),
1165 sha1_to_hex(merge->object.sha1),
1166 sha1_to_hex((*result)->object.sha1));
1167 }
1169 return clean;
1170 }
1172 /*
1173 * Merge the commits h1 and h2, return the resulting virtual
1174 * commit object and a flag indicating the cleaness of the merge.
1175 */
1176 static
1177 int merge(struct commit *h1,
1178 struct commit *h2,
1179 const char *branch1Name,
1180 const char *branch2Name,
1181 int call_depth /* =0 */,
1182 struct commit *ancestor /* =None */,
1183 struct commit **result)
1184 {
1185 struct commit_list *ca = NULL, *iter;
1186 struct commit *merged_common_ancestors;
1187 struct tree *mrtree;
1188 int clean;
1190 output("Merging:");
1191 output_commit_title(h1);
1192 output_commit_title(h2);
1194 if (ancestor)
1195 commit_list_insert(ancestor, &ca);
1196 else
1197 ca = get_merge_bases(h1, h2, 1);
1199 output("found %u common ancestor(s):", commit_list_count(ca));
1200 for (iter = ca; iter; iter = iter->next)
1201 output_commit_title(iter->item);
1203 merged_common_ancestors = pop_commit(&ca);
1205 for (iter = ca; iter; iter = iter->next) {
1206 output_indent = call_depth + 1;
1207 /*
1208 * When the merge fails, the result contains files
1209 * with conflict markers. The cleanness flag is
1210 * ignored, it was never acutally used, as result of
1211 * merge_trees has always overwritten it: the commited
1212 * "conflicts" were already resolved.
1213 */
1214 merge(merged_common_ancestors, iter->item,
1215 "Temporary merge branch 1",
1216 "Temporary merge branch 2",
1217 call_depth + 1,
1218 NULL,
1219 &merged_common_ancestors);
1220 output_indent = call_depth;
1222 if (!merged_common_ancestors)
1223 die("merge returned no commit");
1224 }
1226 if (call_depth == 0) {
1227 setup_index(0 /* $GIT_DIR/index */);
1228 index_only = 0;
1229 } else {
1230 setup_index(1 /* temporary index */);
1231 git_read_tree(h1->tree);
1232 index_only = 1;
1233 }
1235 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1236 branch1Name, branch2Name, &mrtree);
1238 if (!ancestor && (clean || index_only)) {
1239 *result = make_virtual_commit(mrtree, "merged tree");
1240 commit_list_insert(h1, &(*result)->parents);
1241 commit_list_insert(h2, &(*result)->parents->next);
1242 } else
1243 *result = NULL;
1245 return clean;
1246 }
1248 static struct commit *get_ref(const char *ref)
1249 {
1250 unsigned char sha1[20];
1251 struct object *object;
1253 if (get_sha1(ref, sha1))
1254 die("Could not resolve ref '%s'", ref);
1255 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1256 if (object->type != OBJ_COMMIT)
1257 return NULL;
1258 if (parse_commit((struct commit *)object))
1259 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1260 return (struct commit *)object;
1261 }
1263 int main(int argc, char *argv[])
1264 {
1265 static const char *bases[2];
1266 static unsigned bases_count = 0;
1267 int i, clean;
1268 const char *branch1, *branch2;
1269 struct commit *result, *h1, *h2;
1271 original_index_file = getenv("GIT_INDEX_FILE");
1273 if (!original_index_file)
1274 original_index_file = strdup(git_path("index"));
1276 temporary_index_file = strdup(git_path("mrg-rcrsv-tmp-idx"));
1278 if (argc < 4)
1279 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1281 for (i = 1; i < argc; ++i) {
1282 if (!strcmp(argv[i], "--"))
1283 break;
1284 if (bases_count < sizeof(bases)/sizeof(*bases))
1285 bases[bases_count++] = argv[i];
1286 }
1287 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1288 die("Not handling anything other than two heads merge.");
1290 branch1 = argv[++i];
1291 branch2 = argv[++i];
1292 printf("Merging %s with %s\n", branch1, branch2);
1294 h1 = get_ref(branch1);
1295 h2 = get_ref(branch2);
1297 if (bases_count == 1) {
1298 struct commit *ancestor = get_ref(bases[0]);
1299 clean = merge(h1, h2, branch1, branch2, 0, ancestor, &result);
1300 } else
1301 clean = merge(h1, h2, branch1, branch2, 0, NULL, &result);
1303 if (cache_dirty)
1304 flush_cache();
1306 return clean ? 0: 1;
1307 }
1309 /*
1310 vim: sw=8 noet
1311 */