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5bb20aa8ba7a69b7f2f8404b6bcadbff97802755
1 /*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6 #include "cache.h"
7 #include "cache-tree.h"
8 #include "commit.h"
9 #include "blob.h"
10 #include "builtin.h"
11 #include "tree-walk.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "tag.h"
15 #include "unpack-trees.h"
16 #include "string-list.h"
17 #include "xdiff-interface.h"
18 #include "ll-merge.h"
19 #include "interpolate.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
23 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
24 {
25 unsigned char shifted[20];
27 /*
28 * NEEDSWORK: this limits the recursion depth to hardcoded
29 * value '2' to avoid excessive overhead.
30 */
31 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
32 if (!hashcmp(two->object.sha1, shifted))
33 return two;
34 return lookup_tree(shifted);
35 }
37 /*
38 * A virtual commit has
39 * - (const char *)commit->util set to the name, and
40 * - *(int *)commit->object.sha1 set to the virtual id.
41 */
43 struct commit *make_virtual_commit(struct tree *tree, const char *comment)
44 {
45 struct commit *commit = xcalloc(1, sizeof(struct commit));
46 static unsigned virtual_id = 1;
47 commit->tree = tree;
48 commit->util = (void*)comment;
49 *(int*)commit->object.sha1 = virtual_id++;
50 /* avoid warnings */
51 commit->object.parsed = 1;
52 return commit;
53 }
55 /*
56 * Since we use get_tree_entry(), which does not put the read object into
57 * the object pool, we cannot rely on a == b.
58 */
59 static int sha_eq(const unsigned char *a, const unsigned char *b)
60 {
61 if (!a && !b)
62 return 2;
63 return a && b && hashcmp(a, b) == 0;
64 }
66 /*
67 * Since we want to write the index eventually, we cannot reuse the index
68 * for these (temporary) data.
69 */
70 struct stage_data
71 {
72 struct
73 {
74 unsigned mode;
75 unsigned char sha[20];
76 } stages[4];
77 unsigned processed:1;
78 };
80 static struct string_list current_file_set = {NULL, 0, 0, 1};
81 static struct string_list current_directory_set = {NULL, 0, 0, 1};
83 static struct strbuf obuf = STRBUF_INIT;
85 static int show(struct merge_options *o, int v)
86 {
87 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
88 }
90 static void flush_output(void)
91 {
92 if (obuf.len) {
93 fputs(obuf.buf, stdout);
94 strbuf_reset(&obuf);
95 }
96 }
98 static void output(struct merge_options *o, int v, const char *fmt, ...)
99 {
100 int len;
101 va_list ap;
103 if (!show(o, v))
104 return;
106 strbuf_grow(&obuf, o->call_depth * 2 + 2);
107 memset(obuf.buf + obuf.len, ' ', o->call_depth * 2);
108 strbuf_setlen(&obuf, obuf.len + o->call_depth * 2);
110 va_start(ap, fmt);
111 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
112 va_end(ap);
114 if (len < 0)
115 len = 0;
116 if (len >= strbuf_avail(&obuf)) {
117 strbuf_grow(&obuf, len + 2);
118 va_start(ap, fmt);
119 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
120 va_end(ap);
121 if (len >= strbuf_avail(&obuf)) {
122 die("this should not happen, your snprintf is broken");
123 }
124 }
125 strbuf_setlen(&obuf, obuf.len + len);
126 strbuf_add(&obuf, "\n", 1);
127 if (!o->buffer_output)
128 flush_output();
129 }
131 static void output_commit_title(struct merge_options *o, struct commit *commit)
132 {
133 int i;
134 flush_output();
135 for (i = o->call_depth; i--;)
136 fputs(" ", stdout);
137 if (commit->util)
138 printf("virtual %s\n", (char *)commit->util);
139 else {
140 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
141 if (parse_commit(commit) != 0)
142 printf("(bad commit)\n");
143 else {
144 const char *s;
145 int len;
146 for (s = commit->buffer; *s; s++)
147 if (*s == '\n' && s[1] == '\n') {
148 s += 2;
149 break;
150 }
151 for (len = 0; s[len] && '\n' != s[len]; len++)
152 ; /* do nothing */
153 printf("%.*s\n", len, s);
154 }
155 }
156 }
158 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
159 const char *path, int stage, int refresh, int options)
160 {
161 struct cache_entry *ce;
162 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
163 if (!ce)
164 return error("addinfo_cache failed for path '%s'", path);
165 return add_cache_entry(ce, options);
166 }
168 /*
169 * This is a global variable which is used in a number of places but
170 * only written to in the 'merge' function.
171 *
172 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
173 * don't update the working directory.
174 * 0 => Leave unmerged entries in the cache and update
175 * the working directory.
176 */
177 static int index_only = 0;
179 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
180 {
181 parse_tree(tree);
182 init_tree_desc(desc, tree->buffer, tree->size);
183 }
185 static int git_merge_trees(int index_only,
186 struct tree *common,
187 struct tree *head,
188 struct tree *merge)
189 {
190 int rc;
191 struct tree_desc t[3];
192 struct unpack_trees_options opts;
194 memset(&opts, 0, sizeof(opts));
195 if (index_only)
196 opts.index_only = 1;
197 else
198 opts.update = 1;
199 opts.merge = 1;
200 opts.head_idx = 2;
201 opts.fn = threeway_merge;
202 opts.src_index = &the_index;
203 opts.dst_index = &the_index;
205 init_tree_desc_from_tree(t+0, common);
206 init_tree_desc_from_tree(t+1, head);
207 init_tree_desc_from_tree(t+2, merge);
209 rc = unpack_trees(3, t, &opts);
210 cache_tree_free(&active_cache_tree);
211 return rc;
212 }
214 struct tree *write_tree_from_memory(struct merge_options *o)
215 {
216 struct tree *result = NULL;
218 if (unmerged_cache()) {
219 int i;
220 output(o, 0, "There are unmerged index entries:");
221 for (i = 0; i < active_nr; i++) {
222 struct cache_entry *ce = active_cache[i];
223 if (ce_stage(ce))
224 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
225 }
226 return NULL;
227 }
229 if (!active_cache_tree)
230 active_cache_tree = cache_tree();
232 if (!cache_tree_fully_valid(active_cache_tree) &&
233 cache_tree_update(active_cache_tree,
234 active_cache, active_nr, 0, 0) < 0)
235 die("error building trees");
237 result = lookup_tree(active_cache_tree->sha1);
239 return result;
240 }
242 static int save_files_dirs(const unsigned char *sha1,
243 const char *base, int baselen, const char *path,
244 unsigned int mode, int stage, void *context)
245 {
246 int len = strlen(path);
247 char *newpath = xmalloc(baselen + len + 1);
248 memcpy(newpath, base, baselen);
249 memcpy(newpath + baselen, path, len);
250 newpath[baselen + len] = '\0';
252 if (S_ISDIR(mode))
253 string_list_insert(newpath, ¤t_directory_set);
254 else
255 string_list_insert(newpath, ¤t_file_set);
256 free(newpath);
258 return READ_TREE_RECURSIVE;
259 }
261 static int get_files_dirs(struct tree *tree)
262 {
263 int n;
264 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, NULL))
265 return 0;
266 n = current_file_set.nr + current_directory_set.nr;
267 return n;
268 }
270 /*
271 * Returns an index_entry instance which doesn't have to correspond to
272 * a real cache entry in Git's index.
273 */
274 static struct stage_data *insert_stage_data(const char *path,
275 struct tree *o, struct tree *a, struct tree *b,
276 struct string_list *entries)
277 {
278 struct string_list_item *item;
279 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
280 get_tree_entry(o->object.sha1, path,
281 e->stages[1].sha, &e->stages[1].mode);
282 get_tree_entry(a->object.sha1, path,
283 e->stages[2].sha, &e->stages[2].mode);
284 get_tree_entry(b->object.sha1, path,
285 e->stages[3].sha, &e->stages[3].mode);
286 item = string_list_insert(path, entries);
287 item->util = e;
288 return e;
289 }
291 /*
292 * Create a dictionary mapping file names to stage_data objects. The
293 * dictionary contains one entry for every path with a non-zero stage entry.
294 */
295 static struct string_list *get_unmerged(void)
296 {
297 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
298 int i;
300 unmerged->strdup_strings = 1;
302 for (i = 0; i < active_nr; i++) {
303 struct string_list_item *item;
304 struct stage_data *e;
305 struct cache_entry *ce = active_cache[i];
306 if (!ce_stage(ce))
307 continue;
309 item = string_list_lookup(ce->name, unmerged);
310 if (!item) {
311 item = string_list_insert(ce->name, unmerged);
312 item->util = xcalloc(1, sizeof(struct stage_data));
313 }
314 e = item->util;
315 e->stages[ce_stage(ce)].mode = ce->ce_mode;
316 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
317 }
319 return unmerged;
320 }
322 struct rename
323 {
324 struct diff_filepair *pair;
325 struct stage_data *src_entry;
326 struct stage_data *dst_entry;
327 unsigned processed:1;
328 };
330 /*
331 * Get information of all renames which occurred between 'o_tree' and
332 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
333 * 'b_tree') to be able to associate the correct cache entries with
334 * the rename information. 'tree' is always equal to either a_tree or b_tree.
335 */
336 static struct string_list *get_renames(struct merge_options *o,
337 struct tree *tree,
338 struct tree *o_tree,
339 struct tree *a_tree,
340 struct tree *b_tree,
341 struct string_list *entries)
342 {
343 int i;
344 struct string_list *renames;
345 struct diff_options opts;
347 renames = xcalloc(1, sizeof(struct string_list));
348 diff_setup(&opts);
349 DIFF_OPT_SET(&opts, RECURSIVE);
350 opts.detect_rename = DIFF_DETECT_RENAME;
351 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
352 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
353 500;
354 opts.warn_on_too_large_rename = 1;
355 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
356 if (diff_setup_done(&opts) < 0)
357 die("diff setup failed");
358 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
359 diffcore_std(&opts);
360 for (i = 0; i < diff_queued_diff.nr; ++i) {
361 struct string_list_item *item;
362 struct rename *re;
363 struct diff_filepair *pair = diff_queued_diff.queue[i];
364 if (pair->status != 'R') {
365 diff_free_filepair(pair);
366 continue;
367 }
368 re = xmalloc(sizeof(*re));
369 re->processed = 0;
370 re->pair = pair;
371 item = string_list_lookup(re->pair->one->path, entries);
372 if (!item)
373 re->src_entry = insert_stage_data(re->pair->one->path,
374 o_tree, a_tree, b_tree, entries);
375 else
376 re->src_entry = item->util;
378 item = string_list_lookup(re->pair->two->path, entries);
379 if (!item)
380 re->dst_entry = insert_stage_data(re->pair->two->path,
381 o_tree, a_tree, b_tree, entries);
382 else
383 re->dst_entry = item->util;
384 item = string_list_insert(pair->one->path, renames);
385 item->util = re;
386 }
387 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
388 diff_queued_diff.nr = 0;
389 diff_flush(&opts);
390 return renames;
391 }
393 static int update_stages(const char *path, struct diff_filespec *o,
394 struct diff_filespec *a, struct diff_filespec *b,
395 int clear)
396 {
397 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
398 if (clear)
399 if (remove_file_from_cache(path))
400 return -1;
401 if (o)
402 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
403 return -1;
404 if (a)
405 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
406 return -1;
407 if (b)
408 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
409 return -1;
410 return 0;
411 }
413 static int remove_path(const char *name)
414 {
415 int ret;
416 char *slash, *dirs;
418 ret = unlink(name);
419 if (ret)
420 return ret;
421 dirs = xstrdup(name);
422 while ((slash = strrchr(name, '/'))) {
423 *slash = '\0';
424 if (rmdir(name) != 0)
425 break;
426 }
427 free(dirs);
428 return ret;
429 }
431 static int remove_file(int clean, const char *path, int no_wd)
432 {
433 int update_cache = index_only || clean;
434 int update_working_directory = !index_only && !no_wd;
436 if (update_cache) {
437 if (remove_file_from_cache(path))
438 return -1;
439 }
440 if (update_working_directory) {
441 unlink(path);
442 if (errno != ENOENT || errno != EISDIR)
443 return -1;
444 remove_path(path);
445 }
446 return 0;
447 }
449 static char *unique_path(const char *path, const char *branch)
450 {
451 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
452 int suffix = 0;
453 struct stat st;
454 char *p = newpath + strlen(path);
455 strcpy(newpath, path);
456 *(p++) = '~';
457 strcpy(p, branch);
458 for (; *p; ++p)
459 if ('/' == *p)
460 *p = '_';
461 while (string_list_has_string(¤t_file_set, newpath) ||
462 string_list_has_string(¤t_directory_set, newpath) ||
463 lstat(newpath, &st) == 0)
464 sprintf(p, "_%d", suffix++);
466 string_list_insert(newpath, ¤t_file_set);
467 return newpath;
468 }
470 static void flush_buffer(int fd, const char *buf, unsigned long size)
471 {
472 while (size > 0) {
473 long ret = write_in_full(fd, buf, size);
474 if (ret < 0) {
475 /* Ignore epipe */
476 if (errno == EPIPE)
477 break;
478 die("merge-recursive: %s", strerror(errno));
479 } else if (!ret) {
480 die("merge-recursive: disk full?");
481 }
482 size -= ret;
483 buf += ret;
484 }
485 }
487 static int make_room_for_path(const char *path)
488 {
489 int status;
490 const char *msg = "failed to create path '%s'%s";
492 status = safe_create_leading_directories_const(path);
493 if (status) {
494 if (status == -3) {
495 /* something else exists */
496 error(msg, path, ": perhaps a D/F conflict?");
497 return -1;
498 }
499 die(msg, path, "");
500 }
502 /* Successful unlink is good.. */
503 if (!unlink(path))
504 return 0;
505 /* .. and so is no existing file */
506 if (errno == ENOENT)
507 return 0;
508 /* .. but not some other error (who really cares what?) */
509 return error(msg, path, ": perhaps a D/F conflict?");
510 }
512 static void update_file_flags(const unsigned char *sha,
513 unsigned mode,
514 const char *path,
515 int update_cache,
516 int update_wd)
517 {
518 if (index_only)
519 update_wd = 0;
521 if (update_wd) {
522 enum object_type type;
523 void *buf;
524 unsigned long size;
526 if (S_ISGITLINK(mode))
527 die("cannot read object %s '%s': It is a submodule!",
528 sha1_to_hex(sha), path);
530 buf = read_sha1_file(sha, &type, &size);
531 if (!buf)
532 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
533 if (type != OBJ_BLOB)
534 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
535 if (S_ISREG(mode)) {
536 struct strbuf strbuf;
537 strbuf_init(&strbuf, 0);
538 if (convert_to_working_tree(path, buf, size, &strbuf)) {
539 free(buf);
540 size = strbuf.len;
541 buf = strbuf_detach(&strbuf, NULL);
542 }
543 }
545 if (make_room_for_path(path) < 0) {
546 update_wd = 0;
547 free(buf);
548 goto update_index;
549 }
550 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
551 int fd;
552 if (mode & 0100)
553 mode = 0777;
554 else
555 mode = 0666;
556 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
557 if (fd < 0)
558 die("failed to open %s: %s", path, strerror(errno));
559 flush_buffer(fd, buf, size);
560 close(fd);
561 } else if (S_ISLNK(mode)) {
562 char *lnk = xmemdupz(buf, size);
563 safe_create_leading_directories_const(path);
564 unlink(path);
565 symlink(lnk, path);
566 free(lnk);
567 } else
568 die("do not know what to do with %06o %s '%s'",
569 mode, sha1_to_hex(sha), path);
570 free(buf);
571 }
572 update_index:
573 if (update_cache)
574 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
575 }
577 static void update_file(int clean,
578 const unsigned char *sha,
579 unsigned mode,
580 const char *path)
581 {
582 update_file_flags(sha, mode, path, index_only || clean, !index_only);
583 }
585 /* Low level file merging, update and removal */
587 struct merge_file_info
588 {
589 unsigned char sha[20];
590 unsigned mode;
591 unsigned clean:1,
592 merge:1;
593 };
595 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
596 {
597 unsigned long size;
598 enum object_type type;
600 if (!hashcmp(sha1, null_sha1)) {
601 mm->ptr = xstrdup("");
602 mm->size = 0;
603 return;
604 }
606 mm->ptr = read_sha1_file(sha1, &type, &size);
607 if (!mm->ptr || type != OBJ_BLOB)
608 die("unable to read blob object %s", sha1_to_hex(sha1));
609 mm->size = size;
610 }
612 static int merge_3way(mmbuffer_t *result_buf,
613 struct diff_filespec *o,
614 struct diff_filespec *a,
615 struct diff_filespec *b,
616 const char *branch1,
617 const char *branch2)
618 {
619 mmfile_t orig, src1, src2;
620 char *name1, *name2;
621 int merge_status;
623 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
624 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
626 fill_mm(o->sha1, &orig);
627 fill_mm(a->sha1, &src1);
628 fill_mm(b->sha1, &src2);
630 merge_status = ll_merge(result_buf, a->path, &orig,
631 &src1, name1, &src2, name2,
632 index_only);
634 free(name1);
635 free(name2);
636 free(orig.ptr);
637 free(src1.ptr);
638 free(src2.ptr);
639 return merge_status;
640 }
642 static struct merge_file_info merge_file(struct diff_filespec *o,
643 struct diff_filespec *a, struct diff_filespec *b,
644 const char *branch1, const char *branch2)
645 {
646 struct merge_file_info result;
647 result.merge = 0;
648 result.clean = 1;
650 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
651 result.clean = 0;
652 if (S_ISREG(a->mode)) {
653 result.mode = a->mode;
654 hashcpy(result.sha, a->sha1);
655 } else {
656 result.mode = b->mode;
657 hashcpy(result.sha, b->sha1);
658 }
659 } else {
660 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
661 result.merge = 1;
663 /*
664 * Merge modes
665 */
666 if (a->mode == b->mode || a->mode == o->mode)
667 result.mode = b->mode;
668 else {
669 result.mode = a->mode;
670 if (b->mode != o->mode) {
671 result.clean = 0;
672 result.merge = 1;
673 }
674 }
676 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, o->sha1))
677 hashcpy(result.sha, b->sha1);
678 else if (sha_eq(b->sha1, o->sha1))
679 hashcpy(result.sha, a->sha1);
680 else if (S_ISREG(a->mode)) {
681 mmbuffer_t result_buf;
682 int merge_status;
684 merge_status = merge_3way(&result_buf, o, a, b,
685 branch1, branch2);
687 if ((merge_status < 0) || !result_buf.ptr)
688 die("Failed to execute internal merge");
690 if (write_sha1_file(result_buf.ptr, result_buf.size,
691 blob_type, result.sha))
692 die("Unable to add %s to database",
693 a->path);
695 free(result_buf.ptr);
696 result.clean = (merge_status == 0);
697 } else if (S_ISGITLINK(a->mode)) {
698 result.clean = 0;
699 hashcpy(result.sha, a->sha1);
700 } else if (S_ISLNK(a->mode)) {
701 hashcpy(result.sha, a->sha1);
703 if (!sha_eq(a->sha1, b->sha1))
704 result.clean = 0;
705 } else {
706 die("unsupported object type in the tree");
707 }
708 }
710 return result;
711 }
713 static void conflict_rename_rename(struct merge_options *o,
714 struct rename *ren1,
715 const char *branch1,
716 struct rename *ren2,
717 const char *branch2)
718 {
719 char *del[2];
720 int delp = 0;
721 const char *ren1_dst = ren1->pair->two->path;
722 const char *ren2_dst = ren2->pair->two->path;
723 const char *dst_name1 = ren1_dst;
724 const char *dst_name2 = ren2_dst;
725 if (string_list_has_string(¤t_directory_set, ren1_dst)) {
726 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
727 output(o, 1, "%s is a directory in %s adding as %s instead",
728 ren1_dst, branch2, dst_name1);
729 remove_file(0, ren1_dst, 0);
730 }
731 if (string_list_has_string(¤t_directory_set, ren2_dst)) {
732 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
733 output(o, 1, "%s is a directory in %s adding as %s instead",
734 ren2_dst, branch1, dst_name2);
735 remove_file(0, ren2_dst, 0);
736 }
737 if (index_only) {
738 remove_file_from_cache(dst_name1);
739 remove_file_from_cache(dst_name2);
740 /*
741 * Uncomment to leave the conflicting names in the resulting tree
742 *
743 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
744 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
745 */
746 } else {
747 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
748 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
749 }
750 while (delp--)
751 free(del[delp]);
752 }
754 static void conflict_rename_dir(struct merge_options *o,
755 struct rename *ren1,
756 const char *branch1)
757 {
758 char *new_path = unique_path(ren1->pair->two->path, branch1);
759 output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
760 remove_file(0, ren1->pair->two->path, 0);
761 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
762 free(new_path);
763 }
765 static void conflict_rename_rename_2(struct merge_options *o,
766 struct rename *ren1,
767 const char *branch1,
768 struct rename *ren2,
769 const char *branch2)
770 {
771 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
772 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
773 output(o, 1, "Renaming %s to %s and %s to %s instead",
774 ren1->pair->one->path, new_path1,
775 ren2->pair->one->path, new_path2);
776 remove_file(0, ren1->pair->two->path, 0);
777 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
778 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
779 free(new_path2);
780 free(new_path1);
781 }
783 static int process_renames(struct merge_options *o,
784 struct string_list *a_renames,
785 struct string_list *b_renames)
786 {
787 int clean_merge = 1, i, j;
788 struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
789 const struct rename *sre;
791 for (i = 0; i < a_renames->nr; i++) {
792 sre = a_renames->items[i].util;
793 string_list_insert(sre->pair->two->path, &a_by_dst)->util
794 = sre->dst_entry;
795 }
796 for (i = 0; i < b_renames->nr; i++) {
797 sre = b_renames->items[i].util;
798 string_list_insert(sre->pair->two->path, &b_by_dst)->util
799 = sre->dst_entry;
800 }
802 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
803 int compare;
804 char *src;
805 struct string_list *renames1, *renames2, *renames2Dst;
806 struct rename *ren1 = NULL, *ren2 = NULL;
807 const char *branch1, *branch2;
808 const char *ren1_src, *ren1_dst;
810 if (i >= a_renames->nr) {
811 compare = 1;
812 ren2 = b_renames->items[j++].util;
813 } else if (j >= b_renames->nr) {
814 compare = -1;
815 ren1 = a_renames->items[i++].util;
816 } else {
817 compare = strcmp(a_renames->items[i].string,
818 b_renames->items[j].string);
819 if (compare <= 0)
820 ren1 = a_renames->items[i++].util;
821 if (compare >= 0)
822 ren2 = b_renames->items[j++].util;
823 }
825 /* TODO: refactor, so that 1/2 are not needed */
826 if (ren1) {
827 renames1 = a_renames;
828 renames2 = b_renames;
829 renames2Dst = &b_by_dst;
830 branch1 = o->branch1;
831 branch2 = o->branch2;
832 } else {
833 struct rename *tmp;
834 renames1 = b_renames;
835 renames2 = a_renames;
836 renames2Dst = &a_by_dst;
837 branch1 = o->branch2;
838 branch2 = o->branch1;
839 tmp = ren2;
840 ren2 = ren1;
841 ren1 = tmp;
842 }
843 src = ren1->pair->one->path;
845 ren1->dst_entry->processed = 1;
846 ren1->src_entry->processed = 1;
848 if (ren1->processed)
849 continue;
850 ren1->processed = 1;
852 ren1_src = ren1->pair->one->path;
853 ren1_dst = ren1->pair->two->path;
855 if (ren2) {
856 const char *ren2_src = ren2->pair->one->path;
857 const char *ren2_dst = ren2->pair->two->path;
858 /* Renamed in 1 and renamed in 2 */
859 if (strcmp(ren1_src, ren2_src) != 0)
860 die("ren1.src != ren2.src");
861 ren2->dst_entry->processed = 1;
862 ren2->processed = 1;
863 if (strcmp(ren1_dst, ren2_dst) != 0) {
864 clean_merge = 0;
865 output(o, 1, "CONFLICT (rename/rename): "
866 "Rename \"%s\"->\"%s\" in branch \"%s\" "
867 "rename \"%s\"->\"%s\" in \"%s\"%s",
868 src, ren1_dst, branch1,
869 src, ren2_dst, branch2,
870 index_only ? " (left unresolved)": "");
871 if (index_only) {
872 remove_file_from_cache(src);
873 update_file(0, ren1->pair->one->sha1,
874 ren1->pair->one->mode, src);
875 }
876 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
877 } else {
878 struct merge_file_info mfi;
879 remove_file(1, ren1_src, 1);
880 mfi = merge_file(ren1->pair->one,
881 ren1->pair->two,
882 ren2->pair->two,
883 branch1,
884 branch2);
885 if (mfi.merge || !mfi.clean)
886 output(o, 1, "Renaming %s->%s", src, ren1_dst);
888 if (mfi.merge)
889 output(o, 2, "Auto-merging %s", ren1_dst);
891 if (!mfi.clean) {
892 output(o, 1, "CONFLICT (content): merge conflict in %s",
893 ren1_dst);
894 clean_merge = 0;
896 if (!index_only)
897 update_stages(ren1_dst,
898 ren1->pair->one,
899 ren1->pair->two,
900 ren2->pair->two,
901 1 /* clear */);
902 }
903 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
904 }
905 } else {
906 /* Renamed in 1, maybe changed in 2 */
907 struct string_list_item *item;
908 /* we only use sha1 and mode of these */
909 struct diff_filespec src_other, dst_other;
910 int try_merge, stage = a_renames == renames1 ? 3: 2;
912 remove_file(1, ren1_src, index_only || stage == 3);
914 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
915 src_other.mode = ren1->src_entry->stages[stage].mode;
916 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
917 dst_other.mode = ren1->dst_entry->stages[stage].mode;
919 try_merge = 0;
921 if (string_list_has_string(¤t_directory_set, ren1_dst)) {
922 clean_merge = 0;
923 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
924 " directory %s added in %s",
925 ren1_src, ren1_dst, branch1,
926 ren1_dst, branch2);
927 conflict_rename_dir(o, ren1, branch1);
928 } else if (sha_eq(src_other.sha1, null_sha1)) {
929 clean_merge = 0;
930 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
931 "and deleted in %s",
932 ren1_src, ren1_dst, branch1,
933 branch2);
934 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
935 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
936 const char *new_path;
937 clean_merge = 0;
938 try_merge = 1;
939 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
940 "%s added in %s",
941 ren1_src, ren1_dst, branch1,
942 ren1_dst, branch2);
943 new_path = unique_path(ren1_dst, branch2);
944 output(o, 1, "Adding as %s instead", new_path);
945 update_file(0, dst_other.sha1, dst_other.mode, new_path);
946 } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
947 ren2 = item->util;
948 clean_merge = 0;
949 ren2->processed = 1;
950 output(o, 1, "CONFLICT (rename/rename): "
951 "Rename %s->%s in %s. "
952 "Rename %s->%s in %s",
953 ren1_src, ren1_dst, branch1,
954 ren2->pair->one->path, ren2->pair->two->path, branch2);
955 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
956 } else
957 try_merge = 1;
959 if (try_merge) {
960 struct diff_filespec *one, *a, *b;
961 struct merge_file_info mfi;
962 src_other.path = (char *)ren1_src;
964 one = ren1->pair->one;
965 if (a_renames == renames1) {
966 a = ren1->pair->two;
967 b = &src_other;
968 } else {
969 b = ren1->pair->two;
970 a = &src_other;
971 }
972 mfi = merge_file(one, a, b,
973 o->branch1, o->branch2);
975 if (mfi.clean &&
976 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
977 mfi.mode == ren1->pair->two->mode)
978 /*
979 * This messaged is part of
980 * t6022 test. If you change
981 * it update the test too.
982 */
983 output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
984 else {
985 if (mfi.merge || !mfi.clean)
986 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
987 if (mfi.merge)
988 output(o, 2, "Auto-merging %s", ren1_dst);
989 if (!mfi.clean) {
990 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
991 ren1_dst);
992 clean_merge = 0;
994 if (!index_only)
995 update_stages(ren1_dst,
996 one, a, b, 1);
997 }
998 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
999 }
1000 }
1001 }
1002 }
1003 string_list_clear(&a_by_dst, 0);
1004 string_list_clear(&b_by_dst, 0);
1006 return clean_merge;
1007 }
1009 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1010 {
1011 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1012 }
1014 /* Per entry merge function */
1015 static int process_entry(struct merge_options *o,
1016 const char *path, struct stage_data *entry)
1017 {
1018 /*
1019 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1020 print_index_entry("\tpath: ", entry);
1021 */
1022 int clean_merge = 1;
1023 unsigned o_mode = entry->stages[1].mode;
1024 unsigned a_mode = entry->stages[2].mode;
1025 unsigned b_mode = entry->stages[3].mode;
1026 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1027 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1028 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1030 if (o_sha && (!a_sha || !b_sha)) {
1031 /* Case A: Deleted in one */
1032 if ((!a_sha && !b_sha) ||
1033 (sha_eq(a_sha, o_sha) && !b_sha) ||
1034 (!a_sha && sha_eq(b_sha, o_sha))) {
1035 /* Deleted in both or deleted in one and
1036 * unchanged in the other */
1037 if (a_sha)
1038 output(o, 2, "Removing %s", path);
1039 /* do not touch working file if it did not exist */
1040 remove_file(1, path, !a_sha);
1041 } else {
1042 /* Deleted in one and changed in the other */
1043 clean_merge = 0;
1044 if (!a_sha) {
1045 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1046 "and modified in %s. Version %s of %s left in tree.",
1047 path, o->branch1,
1048 o->branch2, o->branch2, path);
1049 update_file(0, b_sha, b_mode, path);
1050 } else {
1051 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1052 "and modified in %s. Version %s of %s left in tree.",
1053 path, o->branch2,
1054 o->branch1, o->branch1, path);
1055 update_file(0, a_sha, a_mode, path);
1056 }
1057 }
1059 } else if ((!o_sha && a_sha && !b_sha) ||
1060 (!o_sha && !a_sha && b_sha)) {
1061 /* Case B: Added in one. */
1062 const char *add_branch;
1063 const char *other_branch;
1064 unsigned mode;
1065 const unsigned char *sha;
1066 const char *conf;
1068 if (a_sha) {
1069 add_branch = o->branch1;
1070 other_branch = o->branch2;
1071 mode = a_mode;
1072 sha = a_sha;
1073 conf = "file/directory";
1074 } else {
1075 add_branch = o->branch2;
1076 other_branch = o->branch1;
1077 mode = b_mode;
1078 sha = b_sha;
1079 conf = "directory/file";
1080 }
1081 if (string_list_has_string(¤t_directory_set, path)) {
1082 const char *new_path = unique_path(path, add_branch);
1083 clean_merge = 0;
1084 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1085 "Adding %s as %s",
1086 conf, path, other_branch, path, new_path);
1087 remove_file(0, path, 0);
1088 update_file(0, sha, mode, new_path);
1089 } else {
1090 output(o, 2, "Adding %s", path);
1091 update_file(1, sha, mode, path);
1092 }
1093 } else if (a_sha && b_sha) {
1094 /* Case C: Added in both (check for same permissions) and */
1095 /* case D: Modified in both, but differently. */
1096 const char *reason = "content";
1097 struct merge_file_info mfi;
1098 struct diff_filespec one, a, b;
1100 if (!o_sha) {
1101 reason = "add/add";
1102 o_sha = (unsigned char *)null_sha1;
1103 }
1104 output(o, 2, "Auto-merging %s", path);
1105 one.path = a.path = b.path = (char *)path;
1106 hashcpy(one.sha1, o_sha);
1107 one.mode = o_mode;
1108 hashcpy(a.sha1, a_sha);
1109 a.mode = a_mode;
1110 hashcpy(b.sha1, b_sha);
1111 b.mode = b_mode;
1113 mfi = merge_file(&one, &a, &b,
1114 o->branch1, o->branch2);
1116 clean_merge = mfi.clean;
1117 if (mfi.clean)
1118 update_file(1, mfi.sha, mfi.mode, path);
1119 else if (S_ISGITLINK(mfi.mode))
1120 output(o, 1, "CONFLICT (submodule): Merge conflict in %s "
1121 "- needs %s", path, sha1_to_hex(b.sha1));
1122 else {
1123 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1124 reason, path);
1126 if (index_only)
1127 update_file(0, mfi.sha, mfi.mode, path);
1128 else
1129 update_file_flags(mfi.sha, mfi.mode, path,
1130 0 /* update_cache */, 1 /* update_working_directory */);
1131 }
1132 } else if (!o_sha && !a_sha && !b_sha) {
1133 /*
1134 * this entry was deleted altogether. a_mode == 0 means
1135 * we had that path and want to actively remove it.
1136 */
1137 remove_file(1, path, !a_mode);
1138 } else
1139 die("Fatal merge failure, shouldn't happen.");
1141 return clean_merge;
1142 }
1144 int merge_trees(struct merge_options *o,
1145 struct tree *head,
1146 struct tree *merge,
1147 struct tree *common,
1148 struct tree **result)
1149 {
1150 int code, clean;
1152 if (o->subtree_merge) {
1153 merge = shift_tree_object(head, merge);
1154 common = shift_tree_object(head, common);
1155 }
1157 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1158 output(o, 0, "Already uptodate!");
1159 *result = head;
1160 return 1;
1161 }
1163 code = git_merge_trees(index_only, common, head, merge);
1165 if (code != 0)
1166 die("merging of trees %s and %s failed",
1167 sha1_to_hex(head->object.sha1),
1168 sha1_to_hex(merge->object.sha1));
1170 if (unmerged_cache()) {
1171 struct string_list *entries, *re_head, *re_merge;
1172 int i;
1173 string_list_clear(¤t_file_set, 1);
1174 string_list_clear(¤t_directory_set, 1);
1175 get_files_dirs(head);
1176 get_files_dirs(merge);
1178 entries = get_unmerged();
1179 re_head = get_renames(o, head, common, head, merge, entries);
1180 re_merge = get_renames(o, merge, common, head, merge, entries);
1181 clean = process_renames(o, re_head, re_merge);
1182 for (i = 0; i < entries->nr; i++) {
1183 const char *path = entries->items[i].string;
1184 struct stage_data *e = entries->items[i].util;
1185 if (!e->processed
1186 && !process_entry(o, path, e))
1187 clean = 0;
1188 }
1190 string_list_clear(re_merge, 0);
1191 string_list_clear(re_head, 0);
1192 string_list_clear(entries, 1);
1194 }
1195 else
1196 clean = 1;
1198 if (index_only)
1199 *result = write_tree_from_memory(o);
1201 return clean;
1202 }
1204 static struct commit_list *reverse_commit_list(struct commit_list *list)
1205 {
1206 struct commit_list *next = NULL, *current, *backup;
1207 for (current = list; current; current = backup) {
1208 backup = current->next;
1209 current->next = next;
1210 next = current;
1211 }
1212 return next;
1213 }
1215 /*
1216 * Merge the commits h1 and h2, return the resulting virtual
1217 * commit object and a flag indicating the cleanness of the merge.
1218 */
1219 int merge_recursive(struct merge_options *o,
1220 struct commit *h1,
1221 struct commit *h2,
1222 struct commit_list *ca,
1223 struct commit **result)
1224 {
1225 struct commit_list *iter;
1226 struct commit *merged_common_ancestors;
1227 struct tree *mrtree = mrtree;
1228 int clean;
1230 if (show(o, 4)) {
1231 output(o, 4, "Merging:");
1232 output_commit_title(o, h1);
1233 output_commit_title(o, h2);
1234 }
1236 if (!ca) {
1237 ca = get_merge_bases(h1, h2, 1);
1238 ca = reverse_commit_list(ca);
1239 }
1241 if (show(o, 5)) {
1242 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1243 for (iter = ca; iter; iter = iter->next)
1244 output_commit_title(o, iter->item);
1245 }
1247 merged_common_ancestors = pop_commit(&ca);
1248 if (merged_common_ancestors == NULL) {
1249 /* if there is no common ancestor, make an empty tree */
1250 struct tree *tree = xcalloc(1, sizeof(struct tree));
1252 tree->object.parsed = 1;
1253 tree->object.type = OBJ_TREE;
1254 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1255 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1256 }
1258 for (iter = ca; iter; iter = iter->next) {
1259 const char *saved_b1, *saved_b2;
1260 o->call_depth++;
1261 /*
1262 * When the merge fails, the result contains files
1263 * with conflict markers. The cleanness flag is
1264 * ignored, it was never actually used, as result of
1265 * merge_trees has always overwritten it: the committed
1266 * "conflicts" were already resolved.
1267 */
1268 discard_cache();
1269 saved_b1 = o->branch1;
1270 saved_b2 = o->branch2;
1271 o->branch1 = "Temporary merge branch 1";
1272 o->branch2 = "Temporary merge branch 2";
1273 merge_recursive(o, merged_common_ancestors, iter->item,
1274 NULL, &merged_common_ancestors);
1275 o->branch1 = saved_b1;
1276 o->branch2 = saved_b2;
1277 o->call_depth--;
1279 if (!merged_common_ancestors)
1280 die("merge returned no commit");
1281 }
1283 discard_cache();
1284 if (!o->call_depth) {
1285 read_cache();
1286 index_only = 0;
1287 } else
1288 index_only = 1;
1290 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1291 &mrtree);
1293 if (index_only) {
1294 *result = make_virtual_commit(mrtree, "merged tree");
1295 commit_list_insert(h1, &(*result)->parents);
1296 commit_list_insert(h2, &(*result)->parents->next);
1297 }
1298 flush_output();
1299 return clean;
1300 }
1302 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1303 {
1304 struct object *object;
1306 object = deref_tag(parse_object(sha1), name, strlen(name));
1307 if (!object)
1308 return NULL;
1309 if (object->type == OBJ_TREE)
1310 return make_virtual_commit((struct tree*)object, name);
1311 if (object->type != OBJ_COMMIT)
1312 return NULL;
1313 if (parse_commit((struct commit *)object))
1314 return NULL;
1315 return (struct commit *)object;
1316 }
1318 int merge_recursive_generic(struct merge_options *o,
1319 const unsigned char *head,
1320 const unsigned char *merge,
1321 int num_base_list,
1322 const unsigned char **base_list,
1323 struct commit **result)
1324 {
1325 int clean, index_fd;
1326 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1327 struct commit *head_commit = get_ref(head, o->branch1);
1328 struct commit *next_commit = get_ref(merge, o->branch2);
1329 struct commit_list *ca = NULL;
1331 if (base_list) {
1332 int i;
1333 for (i = 0; i < num_base_list; ++i) {
1334 struct commit *base;
1335 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1336 return error("Could not parse object '%s'",
1337 sha1_to_hex(base_list[i]));
1338 commit_list_insert(base, &ca);
1339 }
1340 }
1342 index_fd = hold_locked_index(lock, 1);
1343 clean = merge_recursive(o, head_commit, next_commit, ca,
1344 result);
1345 if (active_cache_changed &&
1346 (write_cache(index_fd, active_cache, active_nr) ||
1347 commit_locked_index(lock)))
1348 return error("Unable to write index.");
1350 return clean ? 0 : 1;
1351 }
1353 static int merge_recursive_config(const char *var, const char *value, void *cb)
1354 {
1355 struct merge_options *o = cb;
1356 if (!strcasecmp(var, "merge.verbosity")) {
1357 o->verbosity = git_config_int(var, value);
1358 return 0;
1359 }
1360 if (!strcasecmp(var, "diff.renamelimit")) {
1361 o->diff_rename_limit = git_config_int(var, value);
1362 return 0;
1363 }
1364 if (!strcasecmp(var, "merge.renamelimit")) {
1365 o->merge_rename_limit = git_config_int(var, value);
1366 return 0;
1367 }
1368 return git_default_config(var, value, cb);
1369 }
1371 void init_merge_options(struct merge_options *o)
1372 {
1373 memset(o, 0, sizeof(struct merge_options));
1374 o->verbosity = 2;
1375 o->buffer_output = 1;
1376 o->diff_rename_limit = -1;
1377 o->merge_rename_limit = -1;
1378 git_config(merge_recursive_config, o);
1379 if (getenv("GIT_MERGE_VERBOSITY"))
1380 o->verbosity =
1381 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1382 if (o->verbosity >= 5)
1383 o->buffer_output = 0;
1384 }