Make the MSVC projects use PDB/IDB files named after the project
[git/dscho.git] / unpack-trees.c
blob720f7a161651126872b7357173c10d69d1db7636
1 #define NO_THE_INDEX_COMPATIBILITY_MACROS
2 #include "cache.h"
3 #include "dir.h"
4 #include "tree.h"
5 #include "tree-walk.h"
6 #include "cache-tree.h"
7 #include "unpack-trees.h"
8 #include "progress.h"
9 #include "refs.h"
10 #include "attr.h"
13 * Error messages expected by scripts out of plumbing commands such as
14 * read-tree. Non-scripted Porcelain is not required to use these messages
15 * and in fact are encouraged to reword them to better suit their particular
16 * situation better. See how "git checkout" replaces not_uptodate_file to
17 * explain why it does not allow switching between branches when you have
18 * local changes, for example.
20 static struct unpack_trees_error_msgs unpack_plumbing_errors = {
21 /* would_overwrite */
22 "Entry '%s' would be overwritten by merge. Cannot merge.",
24 /* not_uptodate_file */
25 "Entry '%s' not uptodate. Cannot merge.",
27 /* not_uptodate_dir */
28 "Updating '%s' would lose untracked files in it",
30 /* would_lose_untracked */
31 "Untracked working tree file '%s' would be %s by merge.",
33 /* bind_overlap */
34 "Entry '%s' overlaps with '%s'. Cannot bind.",
37 #define ERRORMSG(o,fld) \
38 ( ((o) && (o)->msgs.fld) \
39 ? ((o)->msgs.fld) \
40 : (unpack_plumbing_errors.fld) )
42 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
43 unsigned int set, unsigned int clear)
45 unsigned int size = ce_size(ce);
46 struct cache_entry *new = xmalloc(size);
48 clear |= CE_HASHED | CE_UNHASHED;
50 memcpy(new, ce, size);
51 new->next = NULL;
52 new->ce_flags = (new->ce_flags & ~clear) | set;
53 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
57 * Unlink the last component and schedule the leading directories for
58 * removal, such that empty directories get removed.
60 static void unlink_entry(struct cache_entry *ce)
62 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
63 return;
64 if (unlink_or_warn(ce->name))
65 return;
66 schedule_dir_for_removal(ce->name, ce_namelen(ce));
69 static struct checkout state;
70 static int check_updates(struct unpack_trees_options *o)
72 unsigned cnt = 0, total = 0;
73 struct progress *progress = NULL;
74 struct index_state *index = &o->result;
75 int i;
76 int errs = 0;
78 if (o->update && o->verbose_update) {
79 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
80 struct cache_entry *ce = index->cache[cnt];
81 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE))
82 total++;
85 progress = start_progress_delay("Checking out files",
86 total, 50, 1);
87 cnt = 0;
90 if (o->update)
91 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
92 for (i = 0; i < index->cache_nr; i++) {
93 struct cache_entry *ce = index->cache[i];
95 if (ce->ce_flags & CE_REMOVE) {
96 display_progress(progress, ++cnt);
97 if (o->update)
98 unlink_entry(ce);
101 remove_marked_cache_entries(&o->result);
102 remove_scheduled_dirs();
104 for (i = 0; i < index->cache_nr; i++) {
105 struct cache_entry *ce = index->cache[i];
107 if (ce->ce_flags & CE_UPDATE) {
108 display_progress(progress, ++cnt);
109 ce->ce_flags &= ~CE_UPDATE;
110 if (o->update) {
111 errs |= checkout_entry(ce, &state, NULL);
115 stop_progress(&progress);
116 if (o->update)
117 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
118 return errs != 0;
121 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
123 int ret = o->fn(src, o);
124 if (ret > 0)
125 ret = 0;
126 return ret;
129 static int unpack_index_entry(struct cache_entry *ce, struct unpack_trees_options *o)
131 struct cache_entry *src[5] = { ce, NULL, };
133 o->pos++;
134 if (ce_stage(ce)) {
135 if (o->skip_unmerged) {
136 add_entry(o, ce, 0, 0);
137 return 0;
140 return call_unpack_fn(src, o);
143 static int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
145 int i;
146 struct tree_desc t[MAX_UNPACK_TREES];
147 struct traverse_info newinfo;
148 struct name_entry *p;
150 p = names;
151 while (!p->mode)
152 p++;
154 newinfo = *info;
155 newinfo.prev = info;
156 newinfo.name = *p;
157 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
158 newinfo.conflicts |= df_conflicts;
160 for (i = 0; i < n; i++, dirmask >>= 1) {
161 const unsigned char *sha1 = NULL;
162 if (dirmask & 1)
163 sha1 = names[i].sha1;
164 fill_tree_descriptor(t+i, sha1);
166 return traverse_trees(n, t, &newinfo);
170 * Compare the traverse-path to the cache entry without actually
171 * having to generate the textual representation of the traverse
172 * path.
174 * NOTE! This *only* compares up to the size of the traverse path
175 * itself - the caller needs to do the final check for the cache
176 * entry having more data at the end!
178 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
180 int len, pathlen, ce_len;
181 const char *ce_name;
183 if (info->prev) {
184 int cmp = do_compare_entry(ce, info->prev, &info->name);
185 if (cmp)
186 return cmp;
188 pathlen = info->pathlen;
189 ce_len = ce_namelen(ce);
191 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
192 if (ce_len < pathlen)
193 return -1;
195 ce_len -= pathlen;
196 ce_name = ce->name + pathlen;
198 len = tree_entry_len(n->path, n->sha1);
199 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
202 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
204 int cmp = do_compare_entry(ce, info, n);
205 if (cmp)
206 return cmp;
209 * Even if the beginning compared identically, the ce should
210 * compare as bigger than a directory leading up to it!
212 return ce_namelen(ce) > traverse_path_len(info, n);
215 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
217 int len = traverse_path_len(info, n);
218 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
220 ce->ce_mode = create_ce_mode(n->mode);
221 ce->ce_flags = create_ce_flags(len, stage);
222 hashcpy(ce->sha1, n->sha1);
223 make_traverse_path(ce->name, info, n);
225 return ce;
228 static int unpack_nondirectories(int n, unsigned long mask,
229 unsigned long dirmask,
230 struct cache_entry **src,
231 const struct name_entry *names,
232 const struct traverse_info *info)
234 int i;
235 struct unpack_trees_options *o = info->data;
236 unsigned long conflicts;
238 /* Do we have *only* directories? Nothing to do */
239 if (mask == dirmask && !src[0])
240 return 0;
242 conflicts = info->conflicts;
243 if (o->merge)
244 conflicts >>= 1;
245 conflicts |= dirmask;
248 * Ok, we've filled in up to any potential index entry in src[0],
249 * now do the rest.
251 for (i = 0; i < n; i++) {
252 int stage;
253 unsigned int bit = 1ul << i;
254 if (conflicts & bit) {
255 src[i + o->merge] = o->df_conflict_entry;
256 continue;
258 if (!(mask & bit))
259 continue;
260 if (!o->merge)
261 stage = 0;
262 else if (i + 1 < o->head_idx)
263 stage = 1;
264 else if (i + 1 > o->head_idx)
265 stage = 3;
266 else
267 stage = 2;
268 src[i + o->merge] = create_ce_entry(info, names + i, stage);
271 if (o->merge)
272 return call_unpack_fn(src, o);
274 for (i = 0; i < n; i++)
275 if (src[i] && src[i] != o->df_conflict_entry)
276 add_entry(o, src[i], 0, 0);
277 return 0;
280 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
282 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
283 struct unpack_trees_options *o = info->data;
284 const struct name_entry *p = names;
286 /* Find first entry with a real name (we could use "mask" too) */
287 while (!p->mode)
288 p++;
290 /* Are we supposed to look at the index too? */
291 if (o->merge) {
292 while (o->pos < o->src_index->cache_nr) {
293 struct cache_entry *ce = o->src_index->cache[o->pos];
294 int cmp = compare_entry(ce, info, p);
295 if (cmp < 0) {
296 if (unpack_index_entry(ce, o) < 0)
297 return -1;
298 continue;
300 if (!cmp) {
301 o->pos++;
302 if (ce_stage(ce)) {
304 * If we skip unmerged index entries, we'll skip this
305 * entry *and* the tree entries associated with it!
307 if (o->skip_unmerged) {
308 add_entry(o, ce, 0, 0);
309 return mask;
312 src[0] = ce;
314 break;
318 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
319 return -1;
321 /* Now handle any directories.. */
322 if (dirmask) {
323 unsigned long conflicts = mask & ~dirmask;
324 if (o->merge) {
325 conflicts <<= 1;
326 if (src[0])
327 conflicts |= 1;
330 /* special case: "diff-index --cached" looking at a tree */
331 if (o->diff_index_cached &&
332 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
333 int matches;
334 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
335 names, info);
337 * Everything under the name matches. Adjust o->pos to
338 * skip the entire hierarchy.
340 if (matches) {
341 o->pos += matches;
342 return mask;
346 if (traverse_trees_recursive(n, dirmask, conflicts,
347 names, info) < 0)
348 return -1;
349 return mask;
352 return mask;
355 static int unpack_failed(struct unpack_trees_options *o, const char *message)
357 discard_index(&o->result);
358 if (!o->gently) {
359 if (message)
360 return error("%s", message);
361 return -1;
363 return -1;
367 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
368 * resulting index, -2 on failure to reflect the changes to the work tree.
370 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
372 int ret;
373 static struct cache_entry *dfc;
375 if (len > MAX_UNPACK_TREES)
376 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
377 memset(&state, 0, sizeof(state));
378 state.base_dir = "";
379 state.force = 1;
380 state.quiet = 1;
381 state.refresh_cache = 1;
383 memset(&o->result, 0, sizeof(o->result));
384 o->result.initialized = 1;
385 if (o->src_index) {
386 o->result.timestamp.sec = o->src_index->timestamp.sec;
387 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
389 o->merge_size = len;
391 if (!dfc)
392 dfc = xcalloc(1, cache_entry_size(0));
393 o->df_conflict_entry = dfc;
395 if (len) {
396 const char *prefix = o->prefix ? o->prefix : "";
397 struct traverse_info info;
399 setup_traverse_info(&info, prefix);
400 info.fn = unpack_callback;
401 info.data = o;
403 if (traverse_trees(len, t, &info) < 0)
404 return unpack_failed(o, NULL);
407 /* Any left-over entries in the index? */
408 if (o->merge) {
409 while (o->pos < o->src_index->cache_nr) {
410 struct cache_entry *ce = o->src_index->cache[o->pos];
411 if (unpack_index_entry(ce, o) < 0)
412 return unpack_failed(o, NULL);
416 if (o->trivial_merges_only && o->nontrivial_merge)
417 return unpack_failed(o, "Merge requires file-level merging");
419 o->src_index = NULL;
420 ret = check_updates(o) ? (-2) : 0;
421 if (o->dst_index)
422 *o->dst_index = o->result;
423 return ret;
426 /* Here come the merge functions */
428 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
430 return error(ERRORMSG(o, would_overwrite), ce->name);
433 static int same(struct cache_entry *a, struct cache_entry *b)
435 if (!!a != !!b)
436 return 0;
437 if (!a && !b)
438 return 1;
439 return a->ce_mode == b->ce_mode &&
440 !hashcmp(a->sha1, b->sha1);
445 * When a CE gets turned into an unmerged entry, we
446 * want it to be up-to-date
448 static int verify_uptodate(struct cache_entry *ce,
449 struct unpack_trees_options *o)
451 struct stat st;
453 if (o->index_only || o->reset || ce_uptodate(ce))
454 return 0;
456 if (!lstat(ce->name, &st)) {
457 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID);
458 if (!changed)
459 return 0;
461 * NEEDSWORK: the current default policy is to allow
462 * submodule to be out of sync wrt the supermodule
463 * index. This needs to be tightened later for
464 * submodules that are marked to be automatically
465 * checked out.
467 if (S_ISGITLINK(ce->ce_mode))
468 return 0;
469 errno = 0;
471 if (errno == ENOENT)
472 return 0;
473 return o->gently ? -1 :
474 error(ERRORMSG(o, not_uptodate_file), ce->name);
477 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
479 if (ce)
480 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
484 * Check that checking out ce->sha1 in subdir ce->name is not
485 * going to overwrite any working files.
487 * Currently, git does not checkout subprojects during a superproject
488 * checkout, so it is not going to overwrite anything.
490 static int verify_clean_submodule(struct cache_entry *ce, const char *action,
491 struct unpack_trees_options *o)
493 return 0;
496 static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
497 struct unpack_trees_options *o)
500 * we are about to extract "ce->name"; we would not want to lose
501 * anything in the existing directory there.
503 int namelen;
504 int i;
505 struct dir_struct d;
506 char *pathbuf;
507 int cnt = 0;
508 unsigned char sha1[20];
510 if (S_ISGITLINK(ce->ce_mode) &&
511 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
512 /* If we are not going to update the submodule, then
513 * we don't care.
515 if (!hashcmp(sha1, ce->sha1))
516 return 0;
517 return verify_clean_submodule(ce, action, o);
521 * First let's make sure we do not have a local modification
522 * in that directory.
524 namelen = strlen(ce->name);
525 for (i = o->pos; i < o->src_index->cache_nr; i++) {
526 struct cache_entry *ce2 = o->src_index->cache[i];
527 int len = ce_namelen(ce2);
528 if (len < namelen ||
529 strncmp(ce->name, ce2->name, namelen) ||
530 ce2->name[namelen] != '/')
531 break;
533 * ce2->name is an entry in the subdirectory.
535 if (!ce_stage(ce2)) {
536 if (verify_uptodate(ce2, o))
537 return -1;
538 add_entry(o, ce2, CE_REMOVE, 0);
540 cnt++;
544 * Then we need to make sure that we do not lose a locally
545 * present file that is not ignored.
547 pathbuf = xmalloc(namelen + 2);
548 memcpy(pathbuf, ce->name, namelen);
549 strcpy(pathbuf+namelen, "/");
551 memset(&d, 0, sizeof(d));
552 if (o->dir)
553 d.exclude_per_dir = o->dir->exclude_per_dir;
554 i = read_directory(&d, pathbuf, namelen+1, NULL);
555 if (i)
556 return o->gently ? -1 :
557 error(ERRORMSG(o, not_uptodate_dir), ce->name);
558 free(pathbuf);
559 return cnt;
563 * This gets called when there was no index entry for the tree entry 'dst',
564 * but we found a file in the working tree that 'lstat()' said was fine,
565 * and we're on a case-insensitive filesystem.
567 * See if we can find a case-insensitive match in the index that also
568 * matches the stat information, and assume it's that other file!
570 static int icase_exists(struct unpack_trees_options *o, struct cache_entry *dst, struct stat *st)
572 struct cache_entry *src;
574 src = index_name_exists(o->src_index, dst->name, ce_namelen(dst), 1);
575 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID);
579 * We do not want to remove or overwrite a working tree file that
580 * is not tracked, unless it is ignored.
582 static int verify_absent(struct cache_entry *ce, const char *action,
583 struct unpack_trees_options *o)
585 struct stat st;
587 if (o->index_only || o->reset || !o->update)
588 return 0;
590 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
591 return 0;
593 if (!lstat(ce->name, &st)) {
594 int ret;
595 int dtype = ce_to_dtype(ce);
596 struct cache_entry *result;
599 * It may be that the 'lstat()' succeeded even though
600 * target 'ce' was absent, because there is an old
601 * entry that is different only in case..
603 * Ignore that lstat() if it matches.
605 if (ignore_case && icase_exists(o, ce, &st))
606 return 0;
608 if (o->dir && excluded(o->dir, ce->name, &dtype))
610 * ce->name is explicitly excluded, so it is Ok to
611 * overwrite it.
613 return 0;
614 if (S_ISDIR(st.st_mode)) {
616 * We are checking out path "foo" and
617 * found "foo/." in the working tree.
618 * This is tricky -- if we have modified
619 * files that are in "foo/" we would lose
620 * it.
622 ret = verify_clean_subdirectory(ce, action, o);
623 if (ret < 0)
624 return ret;
627 * If this removed entries from the index,
628 * what that means is:
630 * (1) the caller unpack_callback() saw path/foo
631 * in the index, and it has not removed it because
632 * it thinks it is handling 'path' as blob with
633 * D/F conflict;
634 * (2) we will return "ok, we placed a merged entry
635 * in the index" which would cause o->pos to be
636 * incremented by one;
637 * (3) however, original o->pos now has 'path/foo'
638 * marked with "to be removed".
640 * We need to increment it by the number of
641 * deleted entries here.
643 o->pos += ret;
644 return 0;
648 * The previous round may already have decided to
649 * delete this path, which is in a subdirectory that
650 * is being replaced with a blob.
652 result = index_name_exists(&o->result, ce->name, ce_namelen(ce), 0);
653 if (result) {
654 if (result->ce_flags & CE_REMOVE)
655 return 0;
658 return o->gently ? -1 :
659 error(ERRORMSG(o, would_lose_untracked), ce->name, action);
661 return 0;
664 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
665 struct unpack_trees_options *o)
667 int update = CE_UPDATE;
669 if (old) {
671 * See if we can re-use the old CE directly?
672 * That way we get the uptodate stat info.
674 * This also removes the UPDATE flag on a match; otherwise
675 * we will end up overwriting local changes in the work tree.
677 if (same(old, merge)) {
678 copy_cache_entry(merge, old);
679 update = 0;
680 } else {
681 if (verify_uptodate(old, o))
682 return -1;
683 invalidate_ce_path(old, o);
686 else {
687 if (verify_absent(merge, "overwritten", o))
688 return -1;
689 invalidate_ce_path(merge, o);
692 add_entry(o, merge, update, CE_STAGEMASK);
693 return 1;
696 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
697 struct unpack_trees_options *o)
699 /* Did it exist in the index? */
700 if (!old) {
701 if (verify_absent(ce, "removed", o))
702 return -1;
703 return 0;
705 if (verify_uptodate(old, o))
706 return -1;
707 add_entry(o, ce, CE_REMOVE, 0);
708 invalidate_ce_path(ce, o);
709 return 1;
712 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
714 add_entry(o, ce, 0, 0);
715 return 1;
718 #if DBRT_DEBUG
719 static void show_stage_entry(FILE *o,
720 const char *label, const struct cache_entry *ce)
722 if (!ce)
723 fprintf(o, "%s (missing)\n", label);
724 else
725 fprintf(o, "%s%06o %s %d\t%s\n",
726 label,
727 ce->ce_mode,
728 sha1_to_hex(ce->sha1),
729 ce_stage(ce),
730 ce->name);
732 #endif
734 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
736 struct cache_entry *index;
737 struct cache_entry *head;
738 struct cache_entry *remote = stages[o->head_idx + 1];
739 int count;
740 int head_match = 0;
741 int remote_match = 0;
743 int df_conflict_head = 0;
744 int df_conflict_remote = 0;
746 int any_anc_missing = 0;
747 int no_anc_exists = 1;
748 int i;
750 for (i = 1; i < o->head_idx; i++) {
751 if (!stages[i] || stages[i] == o->df_conflict_entry)
752 any_anc_missing = 1;
753 else
754 no_anc_exists = 0;
757 index = stages[0];
758 head = stages[o->head_idx];
760 if (head == o->df_conflict_entry) {
761 df_conflict_head = 1;
762 head = NULL;
765 if (remote == o->df_conflict_entry) {
766 df_conflict_remote = 1;
767 remote = NULL;
770 /* First, if there's a #16 situation, note that to prevent #13
771 * and #14.
773 if (!same(remote, head)) {
774 for (i = 1; i < o->head_idx; i++) {
775 if (same(stages[i], head)) {
776 head_match = i;
778 if (same(stages[i], remote)) {
779 remote_match = i;
784 /* We start with cases where the index is allowed to match
785 * something other than the head: #14(ALT) and #2ALT, where it
786 * is permitted to match the result instead.
788 /* #14, #14ALT, #2ALT */
789 if (remote && !df_conflict_head && head_match && !remote_match) {
790 if (index && !same(index, remote) && !same(index, head))
791 return o->gently ? -1 : reject_merge(index, o);
792 return merged_entry(remote, index, o);
795 * If we have an entry in the index cache, then we want to
796 * make sure that it matches head.
798 if (index && !same(index, head))
799 return o->gently ? -1 : reject_merge(index, o);
801 if (head) {
802 /* #5ALT, #15 */
803 if (same(head, remote))
804 return merged_entry(head, index, o);
805 /* #13, #3ALT */
806 if (!df_conflict_remote && remote_match && !head_match)
807 return merged_entry(head, index, o);
810 /* #1 */
811 if (!head && !remote && any_anc_missing)
812 return 0;
814 /* Under the new "aggressive" rule, we resolve mostly trivial
815 * cases that we historically had git-merge-one-file resolve.
817 if (o->aggressive) {
818 int head_deleted = !head && !df_conflict_head;
819 int remote_deleted = !remote && !df_conflict_remote;
820 struct cache_entry *ce = NULL;
822 if (index)
823 ce = index;
824 else if (head)
825 ce = head;
826 else if (remote)
827 ce = remote;
828 else {
829 for (i = 1; i < o->head_idx; i++) {
830 if (stages[i] && stages[i] != o->df_conflict_entry) {
831 ce = stages[i];
832 break;
838 * Deleted in both.
839 * Deleted in one and unchanged in the other.
841 if ((head_deleted && remote_deleted) ||
842 (head_deleted && remote && remote_match) ||
843 (remote_deleted && head && head_match)) {
844 if (index)
845 return deleted_entry(index, index, o);
846 if (ce && !head_deleted) {
847 if (verify_absent(ce, "removed", o))
848 return -1;
850 return 0;
853 * Added in both, identically.
855 if (no_anc_exists && head && remote && same(head, remote))
856 return merged_entry(head, index, o);
860 /* Below are "no merge" cases, which require that the index be
861 * up-to-date to avoid the files getting overwritten with
862 * conflict resolution files.
864 if (index) {
865 if (verify_uptodate(index, o))
866 return -1;
869 o->nontrivial_merge = 1;
871 /* #2, #3, #4, #6, #7, #9, #10, #11. */
872 count = 0;
873 if (!head_match || !remote_match) {
874 for (i = 1; i < o->head_idx; i++) {
875 if (stages[i] && stages[i] != o->df_conflict_entry) {
876 keep_entry(stages[i], o);
877 count++;
878 break;
882 #if DBRT_DEBUG
883 else {
884 fprintf(stderr, "read-tree: warning #16 detected\n");
885 show_stage_entry(stderr, "head ", stages[head_match]);
886 show_stage_entry(stderr, "remote ", stages[remote_match]);
888 #endif
889 if (head) { count += keep_entry(head, o); }
890 if (remote) { count += keep_entry(remote, o); }
891 return count;
895 * Two-way merge.
897 * The rule is to "carry forward" what is in the index without losing
898 * information across a "fast forward", favoring a successful merge
899 * over a merge failure when it makes sense. For details of the
900 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
903 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
905 struct cache_entry *current = src[0];
906 struct cache_entry *oldtree = src[1];
907 struct cache_entry *newtree = src[2];
909 if (o->merge_size != 2)
910 return error("Cannot do a twoway merge of %d trees",
911 o->merge_size);
913 if (oldtree == o->df_conflict_entry)
914 oldtree = NULL;
915 if (newtree == o->df_conflict_entry)
916 newtree = NULL;
918 if (current) {
919 if ((!oldtree && !newtree) || /* 4 and 5 */
920 (!oldtree && newtree &&
921 same(current, newtree)) || /* 6 and 7 */
922 (oldtree && newtree &&
923 same(oldtree, newtree)) || /* 14 and 15 */
924 (oldtree && newtree &&
925 !same(oldtree, newtree) && /* 18 and 19 */
926 same(current, newtree))) {
927 return keep_entry(current, o);
929 else if (oldtree && !newtree && same(current, oldtree)) {
930 /* 10 or 11 */
931 return deleted_entry(oldtree, current, o);
933 else if (oldtree && newtree &&
934 same(current, oldtree) && !same(current, newtree)) {
935 /* 20 or 21 */
936 return merged_entry(newtree, current, o);
938 else {
939 /* all other failures */
940 if (oldtree)
941 return o->gently ? -1 : reject_merge(oldtree, o);
942 if (current)
943 return o->gently ? -1 : reject_merge(current, o);
944 if (newtree)
945 return o->gently ? -1 : reject_merge(newtree, o);
946 return -1;
949 else if (newtree) {
950 if (oldtree && !o->initial_checkout) {
952 * deletion of the path was staged;
954 if (same(oldtree, newtree))
955 return 1;
956 return reject_merge(oldtree, o);
958 return merged_entry(newtree, current, o);
960 return deleted_entry(oldtree, current, o);
964 * Bind merge.
966 * Keep the index entries at stage0, collapse stage1 but make sure
967 * stage0 does not have anything there.
969 int bind_merge(struct cache_entry **src,
970 struct unpack_trees_options *o)
972 struct cache_entry *old = src[0];
973 struct cache_entry *a = src[1];
975 if (o->merge_size != 1)
976 return error("Cannot do a bind merge of %d trees\n",
977 o->merge_size);
978 if (a && old)
979 return o->gently ? -1 :
980 error(ERRORMSG(o, bind_overlap), a->name, old->name);
981 if (!a)
982 return keep_entry(old, o);
983 else
984 return merged_entry(a, NULL, o);
988 * One-way merge.
990 * The rule is:
991 * - take the stat information from stage0, take the data from stage1
993 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
995 struct cache_entry *old = src[0];
996 struct cache_entry *a = src[1];
998 if (o->merge_size != 1)
999 return error("Cannot do a oneway merge of %d trees",
1000 o->merge_size);
1002 if (!a || a == o->df_conflict_entry)
1003 return deleted_entry(old, old, o);
1005 if (old && same(old, a)) {
1006 int update = 0;
1007 if (o->reset && !ce_uptodate(old)) {
1008 struct stat st;
1009 if (lstat(old->name, &st) ||
1010 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID))
1011 update |= CE_UPDATE;
1013 add_entry(o, old, update, 0);
1014 return 0;
1016 return merged_entry(a, old, o);