builtin-rm.c: explain and clarify the "local change" logic
[git/trast.git] / merge-recursive.c
blob0e988f2a0081803f5ee30adbf7a548c2c8a00a05
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 "attr.h"
20 #include "merge-recursive.h"
21 #include "dir.h"
23 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
25 unsigned char shifted[20];
28 * NEEDSWORK: this limits the recursion depth to hardcoded
29 * value '2' to avoid excessive overhead.
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);
38 * A virtual commit has (const char *)commit->util set to the name.
41 struct commit *make_virtual_commit(struct tree *tree, const char *comment)
43 struct commit *commit = xcalloc(1, sizeof(struct commit));
44 commit->tree = tree;
45 commit->util = (void*)comment;
46 /* avoid warnings */
47 commit->object.parsed = 1;
48 return commit;
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.
55 static int sha_eq(const unsigned char *a, const unsigned char *b)
57 if (!a && !b)
58 return 2;
59 return a && b && hashcmp(a, b) == 0;
63 * Since we want to write the index eventually, we cannot reuse the index
64 * for these (temporary) data.
66 struct stage_data
68 struct
70 unsigned mode;
71 unsigned char sha[20];
72 } stages[4];
73 unsigned processed:1;
76 static int show(struct merge_options *o, int v)
78 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
81 static void flush_output(struct merge_options *o)
83 if (o->obuf.len) {
84 fputs(o->obuf.buf, stdout);
85 strbuf_reset(&o->obuf);
89 static void output(struct merge_options *o, int v, const char *fmt, ...)
91 int len;
92 va_list ap;
94 if (!show(o, v))
95 return;
97 strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
98 memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
99 strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
101 va_start(ap, fmt);
102 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
103 va_end(ap);
105 if (len < 0)
106 len = 0;
107 if (len >= strbuf_avail(&o->obuf)) {
108 strbuf_grow(&o->obuf, len + 2);
109 va_start(ap, fmt);
110 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
111 va_end(ap);
112 if (len >= strbuf_avail(&o->obuf)) {
113 die("this should not happen, your snprintf is broken");
116 strbuf_setlen(&o->obuf, o->obuf.len + len);
117 strbuf_add(&o->obuf, "\n", 1);
118 if (!o->buffer_output)
119 flush_output(o);
122 static void output_commit_title(struct merge_options *o, struct commit *commit)
124 int i;
125 flush_output(o);
126 for (i = o->call_depth; i--;)
127 fputs(" ", stdout);
128 if (commit->util)
129 printf("virtual %s\n", (char *)commit->util);
130 else {
131 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
132 if (parse_commit(commit) != 0)
133 printf("(bad commit)\n");
134 else {
135 const char *s;
136 int len;
137 for (s = commit->buffer; *s; s++)
138 if (*s == '\n' && s[1] == '\n') {
139 s += 2;
140 break;
142 for (len = 0; s[len] && '\n' != s[len]; len++)
143 ; /* do nothing */
144 printf("%.*s\n", len, s);
149 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
150 const char *path, int stage, int refresh, int options)
152 struct cache_entry *ce;
153 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
154 if (!ce)
155 return error("addinfo_cache failed for path '%s'", path);
156 return add_cache_entry(ce, options);
159 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
161 parse_tree(tree);
162 init_tree_desc(desc, tree->buffer, tree->size);
165 static int git_merge_trees(int index_only,
166 struct tree *common,
167 struct tree *head,
168 struct tree *merge)
170 int rc;
171 struct tree_desc t[3];
172 struct unpack_trees_options opts;
174 memset(&opts, 0, sizeof(opts));
175 if (index_only)
176 opts.index_only = 1;
177 else
178 opts.update = 1;
179 opts.merge = 1;
180 opts.head_idx = 2;
181 opts.fn = threeway_merge;
182 opts.src_index = &the_index;
183 opts.dst_index = &the_index;
185 init_tree_desc_from_tree(t+0, common);
186 init_tree_desc_from_tree(t+1, head);
187 init_tree_desc_from_tree(t+2, merge);
189 rc = unpack_trees(3, t, &opts);
190 cache_tree_free(&active_cache_tree);
191 return rc;
194 struct tree *write_tree_from_memory(struct merge_options *o)
196 struct tree *result = NULL;
198 if (unmerged_cache()) {
199 int i;
200 output(o, 0, "There are unmerged index entries:");
201 for (i = 0; i < active_nr; i++) {
202 struct cache_entry *ce = active_cache[i];
203 if (ce_stage(ce))
204 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
206 return NULL;
209 if (!active_cache_tree)
210 active_cache_tree = cache_tree();
212 if (!cache_tree_fully_valid(active_cache_tree) &&
213 cache_tree_update(active_cache_tree,
214 active_cache, active_nr, 0, 0) < 0)
215 die("error building trees");
217 result = lookup_tree(active_cache_tree->sha1);
219 return result;
222 static int save_files_dirs(const unsigned char *sha1,
223 const char *base, int baselen, const char *path,
224 unsigned int mode, int stage, void *context)
226 int len = strlen(path);
227 char *newpath = xmalloc(baselen + len + 1);
228 struct merge_options *o = context;
230 memcpy(newpath, base, baselen);
231 memcpy(newpath + baselen, path, len);
232 newpath[baselen + len] = '\0';
234 if (S_ISDIR(mode))
235 string_list_insert(newpath, &o->current_directory_set);
236 else
237 string_list_insert(newpath, &o->current_file_set);
238 free(newpath);
240 return READ_TREE_RECURSIVE;
243 static int get_files_dirs(struct merge_options *o, struct tree *tree)
245 int n;
246 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
247 return 0;
248 n = o->current_file_set.nr + o->current_directory_set.nr;
249 return n;
253 * Returns an index_entry instance which doesn't have to correspond to
254 * a real cache entry in Git's index.
256 static struct stage_data *insert_stage_data(const char *path,
257 struct tree *o, struct tree *a, struct tree *b,
258 struct string_list *entries)
260 struct string_list_item *item;
261 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
262 get_tree_entry(o->object.sha1, path,
263 e->stages[1].sha, &e->stages[1].mode);
264 get_tree_entry(a->object.sha1, path,
265 e->stages[2].sha, &e->stages[2].mode);
266 get_tree_entry(b->object.sha1, path,
267 e->stages[3].sha, &e->stages[3].mode);
268 item = string_list_insert(path, entries);
269 item->util = e;
270 return e;
274 * Create a dictionary mapping file names to stage_data objects. The
275 * dictionary contains one entry for every path with a non-zero stage entry.
277 static struct string_list *get_unmerged(void)
279 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
280 int i;
282 unmerged->strdup_strings = 1;
284 for (i = 0; i < active_nr; i++) {
285 struct string_list_item *item;
286 struct stage_data *e;
287 struct cache_entry *ce = active_cache[i];
288 if (!ce_stage(ce))
289 continue;
291 item = string_list_lookup(ce->name, unmerged);
292 if (!item) {
293 item = string_list_insert(ce->name, unmerged);
294 item->util = xcalloc(1, sizeof(struct stage_data));
296 e = item->util;
297 e->stages[ce_stage(ce)].mode = ce->ce_mode;
298 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
301 return unmerged;
304 struct rename
306 struct diff_filepair *pair;
307 struct stage_data *src_entry;
308 struct stage_data *dst_entry;
309 unsigned processed:1;
313 * Get information of all renames which occurred between 'o_tree' and
314 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
315 * 'b_tree') to be able to associate the correct cache entries with
316 * the rename information. 'tree' is always equal to either a_tree or b_tree.
318 static struct string_list *get_renames(struct merge_options *o,
319 struct tree *tree,
320 struct tree *o_tree,
321 struct tree *a_tree,
322 struct tree *b_tree,
323 struct string_list *entries)
325 int i;
326 struct string_list *renames;
327 struct diff_options opts;
329 renames = xcalloc(1, sizeof(struct string_list));
330 diff_setup(&opts);
331 DIFF_OPT_SET(&opts, RECURSIVE);
332 opts.detect_rename = DIFF_DETECT_RENAME;
333 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
334 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
335 500;
336 opts.warn_on_too_large_rename = 1;
337 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
338 if (diff_setup_done(&opts) < 0)
339 die("diff setup failed");
340 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
341 diffcore_std(&opts);
342 for (i = 0; i < diff_queued_diff.nr; ++i) {
343 struct string_list_item *item;
344 struct rename *re;
345 struct diff_filepair *pair = diff_queued_diff.queue[i];
346 if (pair->status != 'R') {
347 diff_free_filepair(pair);
348 continue;
350 re = xmalloc(sizeof(*re));
351 re->processed = 0;
352 re->pair = pair;
353 item = string_list_lookup(re->pair->one->path, entries);
354 if (!item)
355 re->src_entry = insert_stage_data(re->pair->one->path,
356 o_tree, a_tree, b_tree, entries);
357 else
358 re->src_entry = item->util;
360 item = string_list_lookup(re->pair->two->path, entries);
361 if (!item)
362 re->dst_entry = insert_stage_data(re->pair->two->path,
363 o_tree, a_tree, b_tree, entries);
364 else
365 re->dst_entry = item->util;
366 item = string_list_insert(pair->one->path, renames);
367 item->util = re;
369 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
370 diff_queued_diff.nr = 0;
371 diff_flush(&opts);
372 return renames;
375 static int update_stages(const char *path, struct diff_filespec *o,
376 struct diff_filespec *a, struct diff_filespec *b,
377 int clear)
379 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
380 if (clear)
381 if (remove_file_from_cache(path))
382 return -1;
383 if (o)
384 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
385 return -1;
386 if (a)
387 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
388 return -1;
389 if (b)
390 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
391 return -1;
392 return 0;
395 static int remove_file(struct merge_options *o, int clean,
396 const char *path, int no_wd)
398 int update_cache = o->call_depth || clean;
399 int update_working_directory = !o->call_depth && !no_wd;
401 if (update_cache) {
402 if (remove_file_from_cache(path))
403 return -1;
405 if (update_working_directory) {
406 if (remove_path(path) && errno != ENOENT)
407 return -1;
409 return 0;
412 static char *unique_path(struct merge_options *o, const char *path, const char *branch)
414 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
415 int suffix = 0;
416 struct stat st;
417 char *p = newpath + strlen(path);
418 strcpy(newpath, path);
419 *(p++) = '~';
420 strcpy(p, branch);
421 for (; *p; ++p)
422 if ('/' == *p)
423 *p = '_';
424 while (string_list_has_string(&o->current_file_set, newpath) ||
425 string_list_has_string(&o->current_directory_set, newpath) ||
426 lstat(newpath, &st) == 0)
427 sprintf(p, "_%d", suffix++);
429 string_list_insert(newpath, &o->current_file_set);
430 return newpath;
433 static void flush_buffer(int fd, const char *buf, unsigned long size)
435 while (size > 0) {
436 long ret = write_in_full(fd, buf, size);
437 if (ret < 0) {
438 /* Ignore epipe */
439 if (errno == EPIPE)
440 break;
441 die("merge-recursive: %s", strerror(errno));
442 } else if (!ret) {
443 die("merge-recursive: disk full?");
445 size -= ret;
446 buf += ret;
450 static int make_room_for_path(const char *path)
452 int status;
453 const char *msg = "failed to create path '%s'%s";
455 status = safe_create_leading_directories_const(path);
456 if (status) {
457 if (status == -3) {
458 /* something else exists */
459 error(msg, path, ": perhaps a D/F conflict?");
460 return -1;
462 die(msg, path, "");
465 /* Successful unlink is good.. */
466 if (!unlink(path))
467 return 0;
468 /* .. and so is no existing file */
469 if (errno == ENOENT)
470 return 0;
471 /* .. but not some other error (who really cares what?) */
472 return error(msg, path, ": perhaps a D/F conflict?");
475 static void update_file_flags(struct merge_options *o,
476 const unsigned char *sha,
477 unsigned mode,
478 const char *path,
479 int update_cache,
480 int update_wd)
482 if (o->call_depth)
483 update_wd = 0;
485 if (update_wd) {
486 enum object_type type;
487 void *buf;
488 unsigned long size;
490 if (S_ISGITLINK(mode))
491 die("cannot read object %s '%s': It is a submodule!",
492 sha1_to_hex(sha), path);
494 buf = read_sha1_file(sha, &type, &size);
495 if (!buf)
496 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
497 if (type != OBJ_BLOB)
498 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
499 if (S_ISREG(mode)) {
500 struct strbuf strbuf = STRBUF_INIT;
501 if (convert_to_working_tree(path, buf, size, &strbuf)) {
502 free(buf);
503 size = strbuf.len;
504 buf = strbuf_detach(&strbuf, NULL);
508 if (make_room_for_path(path) < 0) {
509 update_wd = 0;
510 free(buf);
511 goto update_index;
513 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
514 int fd;
515 if (mode & 0100)
516 mode = 0777;
517 else
518 mode = 0666;
519 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
520 if (fd < 0)
521 die("failed to open %s: %s", path, strerror(errno));
522 flush_buffer(fd, buf, size);
523 close(fd);
524 } else if (S_ISLNK(mode)) {
525 char *lnk = xmemdupz(buf, size);
526 safe_create_leading_directories_const(path);
527 unlink(path);
528 symlink(lnk, path);
529 free(lnk);
530 } else
531 die("do not know what to do with %06o %s '%s'",
532 mode, sha1_to_hex(sha), path);
533 free(buf);
535 update_index:
536 if (update_cache)
537 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
540 static void update_file(struct merge_options *o,
541 int clean,
542 const unsigned char *sha,
543 unsigned mode,
544 const char *path)
546 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
549 /* Low level file merging, update and removal */
551 struct merge_file_info
553 unsigned char sha[20];
554 unsigned mode;
555 unsigned clean:1,
556 merge:1;
559 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
561 unsigned long size;
562 enum object_type type;
564 if (!hashcmp(sha1, null_sha1)) {
565 mm->ptr = xstrdup("");
566 mm->size = 0;
567 return;
570 mm->ptr = read_sha1_file(sha1, &type, &size);
571 if (!mm->ptr || type != OBJ_BLOB)
572 die("unable to read blob object %s", sha1_to_hex(sha1));
573 mm->size = size;
576 static int merge_3way(struct merge_options *o,
577 mmbuffer_t *result_buf,
578 struct diff_filespec *one,
579 struct diff_filespec *a,
580 struct diff_filespec *b,
581 const char *branch1,
582 const char *branch2)
584 mmfile_t orig, src1, src2;
585 char *name1, *name2;
586 int merge_status;
588 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
589 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
591 fill_mm(one->sha1, &orig);
592 fill_mm(a->sha1, &src1);
593 fill_mm(b->sha1, &src2);
595 merge_status = ll_merge(result_buf, a->path, &orig,
596 &src1, name1, &src2, name2,
597 o->call_depth);
599 free(name1);
600 free(name2);
601 free(orig.ptr);
602 free(src1.ptr);
603 free(src2.ptr);
604 return merge_status;
607 static struct merge_file_info merge_file(struct merge_options *o,
608 struct diff_filespec *one,
609 struct diff_filespec *a,
610 struct diff_filespec *b,
611 const char *branch1,
612 const char *branch2)
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 hashcpy(result.sha, a->sha1);
623 } else {
624 result.mode = b->mode;
625 hashcpy(result.sha, b->sha1);
627 } else {
628 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
629 result.merge = 1;
632 * Merge modes
634 if (a->mode == b->mode || a->mode == one->mode)
635 result.mode = b->mode;
636 else {
637 result.mode = a->mode;
638 if (b->mode != one->mode) {
639 result.clean = 0;
640 result.merge = 1;
644 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
645 hashcpy(result.sha, b->sha1);
646 else if (sha_eq(b->sha1, one->sha1))
647 hashcpy(result.sha, a->sha1);
648 else if (S_ISREG(a->mode)) {
649 mmbuffer_t result_buf;
650 int merge_status;
652 merge_status = merge_3way(o, &result_buf, one, a, b,
653 branch1, branch2);
655 if ((merge_status < 0) || !result_buf.ptr)
656 die("Failed to execute internal merge");
658 if (write_sha1_file(result_buf.ptr, result_buf.size,
659 blob_type, result.sha))
660 die("Unable to add %s to database",
661 a->path);
663 free(result_buf.ptr);
664 result.clean = (merge_status == 0);
665 } else if (S_ISGITLINK(a->mode)) {
666 result.clean = 0;
667 hashcpy(result.sha, a->sha1);
668 } else if (S_ISLNK(a->mode)) {
669 hashcpy(result.sha, a->sha1);
671 if (!sha_eq(a->sha1, b->sha1))
672 result.clean = 0;
673 } else {
674 die("unsupported object type in the tree");
678 return result;
681 static void conflict_rename_rename(struct merge_options *o,
682 struct rename *ren1,
683 const char *branch1,
684 struct rename *ren2,
685 const char *branch2)
687 char *del[2];
688 int delp = 0;
689 const char *ren1_dst = ren1->pair->two->path;
690 const char *ren2_dst = ren2->pair->two->path;
691 const char *dst_name1 = ren1_dst;
692 const char *dst_name2 = ren2_dst;
693 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
694 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
695 output(o, 1, "%s is a directory in %s adding as %s instead",
696 ren1_dst, branch2, dst_name1);
697 remove_file(o, 0, ren1_dst, 0);
699 if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
700 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
701 output(o, 1, "%s is a directory in %s adding as %s instead",
702 ren2_dst, branch1, dst_name2);
703 remove_file(o, 0, ren2_dst, 0);
705 if (o->call_depth) {
706 remove_file_from_cache(dst_name1);
707 remove_file_from_cache(dst_name2);
709 * Uncomment to leave the conflicting names in the resulting tree
711 * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
712 * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
714 } else {
715 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
716 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
718 while (delp--)
719 free(del[delp]);
722 static void conflict_rename_dir(struct merge_options *o,
723 struct rename *ren1,
724 const char *branch1)
726 char *new_path = unique_path(o, ren1->pair->two->path, branch1);
727 output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
728 remove_file(o, 0, ren1->pair->two->path, 0);
729 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
730 free(new_path);
733 static void conflict_rename_rename_2(struct merge_options *o,
734 struct rename *ren1,
735 const char *branch1,
736 struct rename *ren2,
737 const char *branch2)
739 char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
740 char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
741 output(o, 1, "Renaming %s to %s and %s to %s instead",
742 ren1->pair->one->path, new_path1,
743 ren2->pair->one->path, new_path2);
744 remove_file(o, 0, ren1->pair->two->path, 0);
745 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
746 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
747 free(new_path2);
748 free(new_path1);
751 static int process_renames(struct merge_options *o,
752 struct string_list *a_renames,
753 struct string_list *b_renames)
755 int clean_merge = 1, i, j;
756 struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
757 const struct rename *sre;
759 for (i = 0; i < a_renames->nr; i++) {
760 sre = a_renames->items[i].util;
761 string_list_insert(sre->pair->two->path, &a_by_dst)->util
762 = sre->dst_entry;
764 for (i = 0; i < b_renames->nr; i++) {
765 sre = b_renames->items[i].util;
766 string_list_insert(sre->pair->two->path, &b_by_dst)->util
767 = sre->dst_entry;
770 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
771 int compare;
772 char *src;
773 struct string_list *renames1, *renames2, *renames2Dst;
774 struct rename *ren1 = NULL, *ren2 = NULL;
775 const char *branch1, *branch2;
776 const char *ren1_src, *ren1_dst;
778 if (i >= a_renames->nr) {
779 compare = 1;
780 ren2 = b_renames->items[j++].util;
781 } else if (j >= b_renames->nr) {
782 compare = -1;
783 ren1 = a_renames->items[i++].util;
784 } else {
785 compare = strcmp(a_renames->items[i].string,
786 b_renames->items[j].string);
787 if (compare <= 0)
788 ren1 = a_renames->items[i++].util;
789 if (compare >= 0)
790 ren2 = b_renames->items[j++].util;
793 /* TODO: refactor, so that 1/2 are not needed */
794 if (ren1) {
795 renames1 = a_renames;
796 renames2 = b_renames;
797 renames2Dst = &b_by_dst;
798 branch1 = o->branch1;
799 branch2 = o->branch2;
800 } else {
801 struct rename *tmp;
802 renames1 = b_renames;
803 renames2 = a_renames;
804 renames2Dst = &a_by_dst;
805 branch1 = o->branch2;
806 branch2 = o->branch1;
807 tmp = ren2;
808 ren2 = ren1;
809 ren1 = tmp;
811 src = ren1->pair->one->path;
813 ren1->dst_entry->processed = 1;
814 ren1->src_entry->processed = 1;
816 if (ren1->processed)
817 continue;
818 ren1->processed = 1;
820 ren1_src = ren1->pair->one->path;
821 ren1_dst = ren1->pair->two->path;
823 if (ren2) {
824 const char *ren2_src = ren2->pair->one->path;
825 const char *ren2_dst = ren2->pair->two->path;
826 /* Renamed in 1 and renamed in 2 */
827 if (strcmp(ren1_src, ren2_src) != 0)
828 die("ren1.src != ren2.src");
829 ren2->dst_entry->processed = 1;
830 ren2->processed = 1;
831 if (strcmp(ren1_dst, ren2_dst) != 0) {
832 clean_merge = 0;
833 output(o, 1, "CONFLICT (rename/rename): "
834 "Rename \"%s\"->\"%s\" in branch \"%s\" "
835 "rename \"%s\"->\"%s\" in \"%s\"%s",
836 src, ren1_dst, branch1,
837 src, ren2_dst, branch2,
838 o->call_depth ? " (left unresolved)": "");
839 if (o->call_depth) {
840 remove_file_from_cache(src);
841 update_file(o, 0, ren1->pair->one->sha1,
842 ren1->pair->one->mode, src);
844 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
845 } else {
846 struct merge_file_info mfi;
847 remove_file(o, 1, ren1_src, 1);
848 mfi = merge_file(o,
849 ren1->pair->one,
850 ren1->pair->two,
851 ren2->pair->two,
852 branch1,
853 branch2);
854 if (mfi.merge || !mfi.clean)
855 output(o, 1, "Renaming %s->%s", src, ren1_dst);
857 if (mfi.merge)
858 output(o, 2, "Auto-merging %s", ren1_dst);
860 if (!mfi.clean) {
861 output(o, 1, "CONFLICT (content): merge conflict in %s",
862 ren1_dst);
863 clean_merge = 0;
865 if (!o->call_depth)
866 update_stages(ren1_dst,
867 ren1->pair->one,
868 ren1->pair->two,
869 ren2->pair->two,
870 1 /* clear */);
872 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
874 } else {
875 /* Renamed in 1, maybe changed in 2 */
876 struct string_list_item *item;
877 /* we only use sha1 and mode of these */
878 struct diff_filespec src_other, dst_other;
879 int try_merge, stage = a_renames == renames1 ? 3: 2;
881 remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
883 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
884 src_other.mode = ren1->src_entry->stages[stage].mode;
885 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
886 dst_other.mode = ren1->dst_entry->stages[stage].mode;
888 try_merge = 0;
890 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
891 clean_merge = 0;
892 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
893 " directory %s added in %s",
894 ren1_src, ren1_dst, branch1,
895 ren1_dst, branch2);
896 conflict_rename_dir(o, ren1, branch1);
897 } else if (sha_eq(src_other.sha1, null_sha1)) {
898 clean_merge = 0;
899 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
900 "and deleted in %s",
901 ren1_src, ren1_dst, branch1,
902 branch2);
903 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
904 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
905 const char *new_path;
906 clean_merge = 0;
907 try_merge = 1;
908 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
909 "%s added in %s",
910 ren1_src, ren1_dst, branch1,
911 ren1_dst, branch2);
912 new_path = unique_path(o, ren1_dst, branch2);
913 output(o, 1, "Adding as %s instead", new_path);
914 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
915 } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
916 ren2 = item->util;
917 clean_merge = 0;
918 ren2->processed = 1;
919 output(o, 1, "CONFLICT (rename/rename): "
920 "Rename %s->%s in %s. "
921 "Rename %s->%s in %s",
922 ren1_src, ren1_dst, branch1,
923 ren2->pair->one->path, ren2->pair->two->path, branch2);
924 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
925 } else
926 try_merge = 1;
928 if (try_merge) {
929 struct diff_filespec *one, *a, *b;
930 struct merge_file_info mfi;
931 src_other.path = (char *)ren1_src;
933 one = ren1->pair->one;
934 if (a_renames == renames1) {
935 a = ren1->pair->two;
936 b = &src_other;
937 } else {
938 b = ren1->pair->two;
939 a = &src_other;
941 mfi = merge_file(o, one, a, b,
942 o->branch1, o->branch2);
944 if (mfi.clean &&
945 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
946 mfi.mode == ren1->pair->two->mode)
948 * This messaged is part of
949 * t6022 test. If you change
950 * it update the test too.
952 output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
953 else {
954 if (mfi.merge || !mfi.clean)
955 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
956 if (mfi.merge)
957 output(o, 2, "Auto-merging %s", ren1_dst);
958 if (!mfi.clean) {
959 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
960 ren1_dst);
961 clean_merge = 0;
963 if (!o->call_depth)
964 update_stages(ren1_dst,
965 one, a, b, 1);
967 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
972 string_list_clear(&a_by_dst, 0);
973 string_list_clear(&b_by_dst, 0);
975 return clean_merge;
978 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
980 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
983 /* Per entry merge function */
984 static int process_entry(struct merge_options *o,
985 const char *path, struct stage_data *entry)
988 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
989 print_index_entry("\tpath: ", entry);
991 int clean_merge = 1;
992 unsigned o_mode = entry->stages[1].mode;
993 unsigned a_mode = entry->stages[2].mode;
994 unsigned b_mode = entry->stages[3].mode;
995 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
996 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
997 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
999 if (o_sha && (!a_sha || !b_sha)) {
1000 /* Case A: Deleted in one */
1001 if ((!a_sha && !b_sha) ||
1002 (sha_eq(a_sha, o_sha) && !b_sha) ||
1003 (!a_sha && sha_eq(b_sha, o_sha))) {
1004 /* Deleted in both or deleted in one and
1005 * unchanged in the other */
1006 if (a_sha)
1007 output(o, 2, "Removing %s", path);
1008 /* do not touch working file if it did not exist */
1009 remove_file(o, 1, path, !a_sha);
1010 } else {
1011 /* Deleted in one and changed in the other */
1012 clean_merge = 0;
1013 if (!a_sha) {
1014 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1015 "and modified in %s. Version %s of %s left in tree.",
1016 path, o->branch1,
1017 o->branch2, o->branch2, path);
1018 update_file(o, 0, b_sha, b_mode, path);
1019 } else {
1020 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1021 "and modified in %s. Version %s of %s left in tree.",
1022 path, o->branch2,
1023 o->branch1, o->branch1, path);
1024 update_file(o, 0, a_sha, a_mode, path);
1028 } else if ((!o_sha && a_sha && !b_sha) ||
1029 (!o_sha && !a_sha && b_sha)) {
1030 /* Case B: Added in one. */
1031 const char *add_branch;
1032 const char *other_branch;
1033 unsigned mode;
1034 const unsigned char *sha;
1035 const char *conf;
1037 if (a_sha) {
1038 add_branch = o->branch1;
1039 other_branch = o->branch2;
1040 mode = a_mode;
1041 sha = a_sha;
1042 conf = "file/directory";
1043 } else {
1044 add_branch = o->branch2;
1045 other_branch = o->branch1;
1046 mode = b_mode;
1047 sha = b_sha;
1048 conf = "directory/file";
1050 if (string_list_has_string(&o->current_directory_set, path)) {
1051 const char *new_path = unique_path(o, path, add_branch);
1052 clean_merge = 0;
1053 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1054 "Adding %s as %s",
1055 conf, path, other_branch, path, new_path);
1056 remove_file(o, 0, path, 0);
1057 update_file(o, 0, sha, mode, new_path);
1058 } else {
1059 output(o, 2, "Adding %s", path);
1060 update_file(o, 1, sha, mode, path);
1062 } else if (a_sha && b_sha) {
1063 /* Case C: Added in both (check for same permissions) and */
1064 /* case D: Modified in both, but differently. */
1065 const char *reason = "content";
1066 struct merge_file_info mfi;
1067 struct diff_filespec one, a, b;
1069 if (!o_sha) {
1070 reason = "add/add";
1071 o_sha = (unsigned char *)null_sha1;
1073 output(o, 2, "Auto-merging %s", path);
1074 one.path = a.path = b.path = (char *)path;
1075 hashcpy(one.sha1, o_sha);
1076 one.mode = o_mode;
1077 hashcpy(a.sha1, a_sha);
1078 a.mode = a_mode;
1079 hashcpy(b.sha1, b_sha);
1080 b.mode = b_mode;
1082 mfi = merge_file(o, &one, &a, &b,
1083 o->branch1, o->branch2);
1085 clean_merge = mfi.clean;
1086 if (mfi.clean)
1087 update_file(o, 1, mfi.sha, mfi.mode, path);
1088 else if (S_ISGITLINK(mfi.mode))
1089 output(o, 1, "CONFLICT (submodule): Merge conflict in %s "
1090 "- needs %s", path, sha1_to_hex(b.sha1));
1091 else {
1092 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1093 reason, path);
1095 if (o->call_depth)
1096 update_file(o, 0, mfi.sha, mfi.mode, path);
1097 else
1098 update_file_flags(o, mfi.sha, mfi.mode, path,
1099 0 /* update_cache */, 1 /* update_working_directory */);
1101 } else if (!o_sha && !a_sha && !b_sha) {
1103 * this entry was deleted altogether. a_mode == 0 means
1104 * we had that path and want to actively remove it.
1106 remove_file(o, 1, path, !a_mode);
1107 } else
1108 die("Fatal merge failure, shouldn't happen.");
1110 return clean_merge;
1113 int merge_trees(struct merge_options *o,
1114 struct tree *head,
1115 struct tree *merge,
1116 struct tree *common,
1117 struct tree **result)
1119 int code, clean;
1121 if (o->subtree_merge) {
1122 merge = shift_tree_object(head, merge);
1123 common = shift_tree_object(head, common);
1126 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1127 output(o, 0, "Already uptodate!");
1128 *result = head;
1129 return 1;
1132 code = git_merge_trees(o->call_depth, common, head, merge);
1134 if (code != 0)
1135 die("merging of trees %s and %s failed",
1136 sha1_to_hex(head->object.sha1),
1137 sha1_to_hex(merge->object.sha1));
1139 if (unmerged_cache()) {
1140 struct string_list *entries, *re_head, *re_merge;
1141 int i;
1142 string_list_clear(&o->current_file_set, 1);
1143 string_list_clear(&o->current_directory_set, 1);
1144 get_files_dirs(o, head);
1145 get_files_dirs(o, merge);
1147 entries = get_unmerged();
1148 re_head = get_renames(o, head, common, head, merge, entries);
1149 re_merge = get_renames(o, merge, common, head, merge, entries);
1150 clean = process_renames(o, re_head, re_merge);
1151 for (i = 0; i < entries->nr; i++) {
1152 const char *path = entries->items[i].string;
1153 struct stage_data *e = entries->items[i].util;
1154 if (!e->processed
1155 && !process_entry(o, path, e))
1156 clean = 0;
1159 string_list_clear(re_merge, 0);
1160 string_list_clear(re_head, 0);
1161 string_list_clear(entries, 1);
1164 else
1165 clean = 1;
1167 if (o->call_depth)
1168 *result = write_tree_from_memory(o);
1170 return clean;
1173 static struct commit_list *reverse_commit_list(struct commit_list *list)
1175 struct commit_list *next = NULL, *current, *backup;
1176 for (current = list; current; current = backup) {
1177 backup = current->next;
1178 current->next = next;
1179 next = current;
1181 return next;
1185 * Merge the commits h1 and h2, return the resulting virtual
1186 * commit object and a flag indicating the cleanness of the merge.
1188 int merge_recursive(struct merge_options *o,
1189 struct commit *h1,
1190 struct commit *h2,
1191 struct commit_list *ca,
1192 struct commit **result)
1194 struct commit_list *iter;
1195 struct commit *merged_common_ancestors;
1196 struct tree *mrtree = mrtree;
1197 int clean;
1199 if (show(o, 4)) {
1200 output(o, 4, "Merging:");
1201 output_commit_title(o, h1);
1202 output_commit_title(o, h2);
1205 if (!ca) {
1206 ca = get_merge_bases(h1, h2, 1);
1207 ca = reverse_commit_list(ca);
1210 if (show(o, 5)) {
1211 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1212 for (iter = ca; iter; iter = iter->next)
1213 output_commit_title(o, iter->item);
1216 merged_common_ancestors = pop_commit(&ca);
1217 if (merged_common_ancestors == NULL) {
1218 /* if there is no common ancestor, make an empty tree */
1219 struct tree *tree = xcalloc(1, sizeof(struct tree));
1221 tree->object.parsed = 1;
1222 tree->object.type = OBJ_TREE;
1223 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1224 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1227 for (iter = ca; iter; iter = iter->next) {
1228 const char *saved_b1, *saved_b2;
1229 o->call_depth++;
1231 * When the merge fails, the result contains files
1232 * with conflict markers. The cleanness flag is
1233 * ignored, it was never actually used, as result of
1234 * merge_trees has always overwritten it: the committed
1235 * "conflicts" were already resolved.
1237 discard_cache();
1238 saved_b1 = o->branch1;
1239 saved_b2 = o->branch2;
1240 o->branch1 = "Temporary merge branch 1";
1241 o->branch2 = "Temporary merge branch 2";
1242 merge_recursive(o, merged_common_ancestors, iter->item,
1243 NULL, &merged_common_ancestors);
1244 o->branch1 = saved_b1;
1245 o->branch2 = saved_b2;
1246 o->call_depth--;
1248 if (!merged_common_ancestors)
1249 die("merge returned no commit");
1252 discard_cache();
1253 if (!o->call_depth)
1254 read_cache();
1256 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1257 &mrtree);
1259 if (o->call_depth) {
1260 *result = make_virtual_commit(mrtree, "merged tree");
1261 commit_list_insert(h1, &(*result)->parents);
1262 commit_list_insert(h2, &(*result)->parents->next);
1264 flush_output(o);
1265 return clean;
1268 static struct commit *get_ref(const unsigned char *sha1, const char *name)
1270 struct object *object;
1272 object = deref_tag(parse_object(sha1), name, strlen(name));
1273 if (!object)
1274 return NULL;
1275 if (object->type == OBJ_TREE)
1276 return make_virtual_commit((struct tree*)object, name);
1277 if (object->type != OBJ_COMMIT)
1278 return NULL;
1279 if (parse_commit((struct commit *)object))
1280 return NULL;
1281 return (struct commit *)object;
1284 int merge_recursive_generic(struct merge_options *o,
1285 const unsigned char *head,
1286 const unsigned char *merge,
1287 int num_base_list,
1288 const unsigned char **base_list,
1289 struct commit **result)
1291 int clean, index_fd;
1292 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1293 struct commit *head_commit = get_ref(head, o->branch1);
1294 struct commit *next_commit = get_ref(merge, o->branch2);
1295 struct commit_list *ca = NULL;
1297 if (base_list) {
1298 int i;
1299 for (i = 0; i < num_base_list; ++i) {
1300 struct commit *base;
1301 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1302 return error("Could not parse object '%s'",
1303 sha1_to_hex(base_list[i]));
1304 commit_list_insert(base, &ca);
1308 index_fd = hold_locked_index(lock, 1);
1309 clean = merge_recursive(o, head_commit, next_commit, ca,
1310 result);
1311 if (active_cache_changed &&
1312 (write_cache(index_fd, active_cache, active_nr) ||
1313 commit_locked_index(lock)))
1314 return error("Unable to write index.");
1316 return clean ? 0 : 1;
1319 static int merge_recursive_config(const char *var, const char *value, void *cb)
1321 struct merge_options *o = cb;
1322 if (!strcasecmp(var, "merge.verbosity")) {
1323 o->verbosity = git_config_int(var, value);
1324 return 0;
1326 if (!strcasecmp(var, "diff.renamelimit")) {
1327 o->diff_rename_limit = git_config_int(var, value);
1328 return 0;
1330 if (!strcasecmp(var, "merge.renamelimit")) {
1331 o->merge_rename_limit = git_config_int(var, value);
1332 return 0;
1334 return git_xmerge_config(var, value, cb);
1337 void init_merge_options(struct merge_options *o)
1339 memset(o, 0, sizeof(struct merge_options));
1340 o->verbosity = 2;
1341 o->buffer_output = 1;
1342 o->diff_rename_limit = -1;
1343 o->merge_rename_limit = -1;
1344 git_config(merge_recursive_config, o);
1345 if (getenv("GIT_MERGE_VERBOSITY"))
1346 o->verbosity =
1347 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1348 if (o->verbosity >= 5)
1349 o->buffer_output = 0;
1350 strbuf_init(&o->obuf, 0);
1351 memset(&o->current_file_set, 0, sizeof(struct string_list));
1352 o->current_file_set.strdup_strings = 1;
1353 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1354 o->current_directory_set.strdup_strings = 1;