1 #define NO_THE_INDEX_COMPATIBILITY_MACROS
6 #include "cache-tree.h"
7 #include "unpack-trees.h"
11 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
12 unsigned int set, unsigned int clear)
14 unsigned int size = ce_size(ce);
15 struct cache_entry *new = xmalloc(size);
17 clear |= CE_HASHED | CE_UNHASHED;
19 memcpy(new, ce, size);
21 new->ce_flags = (new->ce_flags & ~clear) | set;
22 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|ADD_CACHE_SKIP_DFCHECK);
25 /* Unlink the last component and attempt to remove leading
26 * directories, in case this unlink is the removal of the
27 * last entry in the directory -- empty directories are removed.
29 static void unlink_entry(char *name, char *last_symlink)
33 if (has_symlink_leading_path(name, last_symlink))
40 cp = strrchr(name, '/');
56 static struct checkout state;
57 static int check_updates(struct unpack_trees_options *o)
59 unsigned cnt = 0, total = 0;
60 struct progress *progress = NULL;
61 char last_symlink[PATH_MAX];
62 struct index_state *index = &o->result;
66 if (o->update && o->verbose_update) {
67 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
68 struct cache_entry *ce = index->cache[cnt];
69 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE))
73 progress = start_progress_delay("Checking out files",
79 for (i = 0; i < index->cache_nr; i++) {
80 struct cache_entry *ce = index->cache[i];
82 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE))
83 display_progress(progress, ++cnt);
84 if (ce->ce_flags & CE_REMOVE) {
86 unlink_entry(ce->name, last_symlink);
87 remove_index_entry_at(&o->result, i);
91 if (ce->ce_flags & CE_UPDATE) {
92 ce->ce_flags &= ~CE_UPDATE;
94 errs |= checkout_entry(ce, &state, NULL);
99 stop_progress(&progress);
103 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
105 int ret = o->fn(src, o);
111 static int unpack_index_entry(struct cache_entry *ce, struct unpack_trees_options *o)
113 struct cache_entry *src[5] = { ce, };
117 if (o->skip_unmerged) {
118 add_entry(o, ce, 0, 0);
122 return call_unpack_fn(src, o);
125 int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
128 struct tree_desc t[MAX_UNPACK_TREES];
129 struct traverse_info newinfo;
130 struct name_entry *p;
139 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
140 newinfo.conflicts |= df_conflicts;
142 for (i = 0; i < n; i++, dirmask >>= 1) {
143 const unsigned char *sha1 = NULL;
145 sha1 = names[i].sha1;
146 fill_tree_descriptor(t+i, sha1);
148 return traverse_trees(n, t, &newinfo);
152 * Compare the traverse-path to the cache entry without actually
153 * having to generate the textual representation of the traverse
156 * NOTE! This *only* compares up to the size of the traverse path
157 * itself - the caller needs to do the final check for the cache
158 * entry having more data at the end!
160 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
162 int len, pathlen, ce_len;
166 int cmp = do_compare_entry(ce, info->prev, &info->name);
170 pathlen = info->pathlen;
171 ce_len = ce_namelen(ce);
173 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
174 if (ce_len < pathlen)
178 ce_name = ce->name + pathlen;
180 len = tree_entry_len(n->path, n->sha1);
181 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
184 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
186 int cmp = do_compare_entry(ce, info, n);
191 * Even if the beginning compared identically, the ce should
192 * compare as bigger than a directory leading up to it!
194 return ce_namelen(ce) > traverse_path_len(info, n);
197 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
199 int len = traverse_path_len(info, n);
200 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
202 ce->ce_mode = create_ce_mode(n->mode);
203 ce->ce_flags = create_ce_flags(len, stage);
204 hashcpy(ce->sha1, n->sha1);
205 make_traverse_path(ce->name, info, n);
210 static int unpack_nondirectories(int n, unsigned long mask, unsigned long dirmask, struct cache_entry *src[5],
211 const struct name_entry *names, const struct traverse_info *info)
214 struct unpack_trees_options *o = info->data;
215 unsigned long conflicts;
217 /* Do we have *only* directories? Nothing to do */
218 if (mask == dirmask && !src[0])
221 conflicts = info->conflicts;
224 conflicts |= dirmask;
227 * Ok, we've filled in up to any potential index entry in src[0],
230 for (i = 0; i < n; i++) {
232 unsigned int bit = 1ul << i;
233 if (conflicts & bit) {
234 src[i + o->merge] = o->df_conflict_entry;
241 else if (i + 1 < o->head_idx)
243 else if (i + 1 > o->head_idx)
247 src[i + o->merge] = create_ce_entry(info, names + i, stage);
251 return call_unpack_fn(src, o);
254 for (i = 0; i < n; i++)
255 add_entry(o, src[i], 0, 0);
259 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
261 struct cache_entry *src[5] = { NULL, };
262 struct unpack_trees_options *o = info->data;
263 const struct name_entry *p = names;
265 /* Find first entry with a real name (we could use "mask" too) */
269 /* Are we supposed to look at the index too? */
271 while (o->pos < o->src_index->cache_nr) {
272 struct cache_entry *ce = o->src_index->cache[o->pos];
273 int cmp = compare_entry(ce, info, p);
275 if (unpack_index_entry(ce, o) < 0)
283 * If we skip unmerged index entries, we'll skip this
284 * entry *and* the tree entries associated with it!
286 if (o->skip_unmerged) {
287 add_entry(o, ce, 0, 0);
297 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
300 /* Now handle any directories.. */
302 unsigned long conflicts = mask & ~dirmask;
308 if (traverse_trees_recursive(n, dirmask, conflicts,
317 static int unpack_failed(struct unpack_trees_options *o, const char *message)
319 discard_index(&o->result);
322 return error(message);
328 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
330 static struct cache_entry *dfc;
332 if (len > MAX_UNPACK_TREES)
333 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
334 memset(&state, 0, sizeof(state));
338 state.refresh_cache = 1;
340 memset(&o->result, 0, sizeof(o->result));
342 o->result.timestamp = o->src_index->timestamp;
346 dfc = xcalloc(1, sizeof(struct cache_entry) + 1);
347 o->df_conflict_entry = dfc;
350 const char *prefix = o->prefix ? o->prefix : "";
351 struct traverse_info info;
353 setup_traverse_info(&info, prefix);
354 info.fn = unpack_callback;
357 if (traverse_trees(len, t, &info) < 0)
358 return unpack_failed(o, NULL);
361 /* Any left-over entries in the index? */
363 while (o->pos < o->src_index->cache_nr) {
364 struct cache_entry *ce = o->src_index->cache[o->pos];
365 if (unpack_index_entry(ce, o) < 0)
366 return unpack_failed(o, NULL);
370 if (o->trivial_merges_only && o->nontrivial_merge)
371 return unpack_failed(o, "Merge requires file-level merging");
374 if (check_updates(o))
377 *o->dst_index = o->result;
381 /* Here come the merge functions */
383 static int reject_merge(struct cache_entry *ce)
385 return error("Entry '%s' would be overwritten by merge. Cannot merge.",
389 static int same(struct cache_entry *a, struct cache_entry *b)
395 return a->ce_mode == b->ce_mode &&
396 !hashcmp(a->sha1, b->sha1);
401 * When a CE gets turned into an unmerged entry, we
402 * want it to be up-to-date
404 static int verify_uptodate(struct cache_entry *ce,
405 struct unpack_trees_options *o)
409 if (o->index_only || o->reset)
412 if (!lstat(ce->name, &st)) {
413 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID);
417 * NEEDSWORK: the current default policy is to allow
418 * submodule to be out of sync wrt the supermodule
419 * index. This needs to be tightened later for
420 * submodules that are marked to be automatically
423 if (S_ISGITLINK(ce->ce_mode))
429 return o->gently ? -1 :
430 error("Entry '%s' not uptodate. Cannot merge.", ce->name);
433 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
436 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
440 * Check that checking out ce->sha1 in subdir ce->name is not
441 * going to overwrite any working files.
443 * Currently, git does not checkout subprojects during a superproject
444 * checkout, so it is not going to overwrite anything.
446 static int verify_clean_submodule(struct cache_entry *ce, const char *action,
447 struct unpack_trees_options *o)
452 static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
453 struct unpack_trees_options *o)
456 * we are about to extract "ce->name"; we would not want to lose
457 * anything in the existing directory there.
464 unsigned char sha1[20];
466 if (S_ISGITLINK(ce->ce_mode) &&
467 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
468 /* If we are not going to update the submodule, then
471 if (!hashcmp(sha1, ce->sha1))
473 return verify_clean_submodule(ce, action, o);
477 * First let's make sure we do not have a local modification
480 namelen = strlen(ce->name);
481 pos = index_name_pos(o->src_index, ce->name, namelen);
483 return cnt; /* we have it as nondirectory */
485 for (i = pos; i < o->src_index->cache_nr; i++) {
486 struct cache_entry *ce = o->src_index->cache[i];
487 int len = ce_namelen(ce);
489 strncmp(ce->name, ce->name, namelen) ||
490 ce->name[namelen] != '/')
493 * ce->name is an entry in the subdirectory.
496 if (verify_uptodate(ce, o))
498 add_entry(o, ce, CE_REMOVE, 0);
504 * Then we need to make sure that we do not lose a locally
505 * present file that is not ignored.
507 pathbuf = xmalloc(namelen + 2);
508 memcpy(pathbuf, ce->name, namelen);
509 strcpy(pathbuf+namelen, "/");
511 memset(&d, 0, sizeof(d));
513 d.exclude_per_dir = o->dir->exclude_per_dir;
514 i = read_directory(&d, ce->name, pathbuf, namelen+1, NULL);
516 return o->gently ? -1 :
517 error("Updating '%s' would lose untracked files in it",
524 * We do not want to remove or overwrite a working tree file that
525 * is not tracked, unless it is ignored.
527 static int verify_absent(struct cache_entry *ce, const char *action,
528 struct unpack_trees_options *o)
532 if (o->index_only || o->reset || !o->update)
535 if (has_symlink_leading_path(ce->name, NULL))
538 if (!lstat(ce->name, &st)) {
540 int dtype = ce_to_dtype(ce);
542 if (o->dir && excluded(o->dir, ce->name, &dtype))
544 * ce->name is explicitly excluded, so it is Ok to
548 if (S_ISDIR(st.st_mode)) {
550 * We are checking out path "foo" and
551 * found "foo/." in the working tree.
552 * This is tricky -- if we have modified
553 * files that are in "foo/" we would lose
556 cnt = verify_clean_subdirectory(ce, action, o);
559 * If this removed entries from the index,
560 * what that means is:
562 * (1) the caller unpack_trees_rec() saw path/foo
563 * in the index, and it has not removed it because
564 * it thinks it is handling 'path' as blob with
566 * (2) we will return "ok, we placed a merged entry
567 * in the index" which would cause o->pos to be
568 * incremented by one;
569 * (3) however, original o->pos now has 'path/foo'
570 * marked with "to be removed".
572 * We need to increment it by the number of
573 * deleted entries here.
580 * The previous round may already have decided to
581 * delete this path, which is in a subdirectory that
582 * is being replaced with a blob.
584 cnt = index_name_pos(&o->result, ce->name, strlen(ce->name));
586 struct cache_entry *ce = o->result.cache[cnt];
587 if (ce->ce_flags & CE_REMOVE)
591 return o->gently ? -1 :
592 error("Untracked working tree file '%s' "
593 "would be %s by merge.", ce->name, action);
598 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
599 struct unpack_trees_options *o)
601 int update = CE_UPDATE;
605 * See if we can re-use the old CE directly?
606 * That way we get the uptodate stat info.
608 * This also removes the UPDATE flag on a match; otherwise
609 * we will end up overwriting local changes in the work tree.
611 if (same(old, merge)) {
612 copy_cache_entry(merge, old);
615 if (verify_uptodate(old, o))
617 invalidate_ce_path(old, o);
621 if (verify_absent(merge, "overwritten", o))
623 invalidate_ce_path(merge, o);
626 add_entry(o, merge, update, CE_STAGEMASK);
630 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
631 struct unpack_trees_options *o)
633 /* Did it exist in the index? */
635 if (verify_absent(ce, "removed", o))
639 if (verify_uptodate(old, o))
641 add_entry(o, ce, CE_REMOVE, 0);
642 invalidate_ce_path(ce, o);
646 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
648 add_entry(o, ce, 0, 0);
653 static void show_stage_entry(FILE *o,
654 const char *label, const struct cache_entry *ce)
657 fprintf(o, "%s (missing)\n", label);
659 fprintf(o, "%s%06o %s %d\t%s\n",
662 sha1_to_hex(ce->sha1),
668 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
670 struct cache_entry *index;
671 struct cache_entry *head;
672 struct cache_entry *remote = stages[o->head_idx + 1];
675 int remote_match = 0;
677 int df_conflict_head = 0;
678 int df_conflict_remote = 0;
680 int any_anc_missing = 0;
681 int no_anc_exists = 1;
684 for (i = 1; i < o->head_idx; i++) {
685 if (!stages[i] || stages[i] == o->df_conflict_entry)
692 head = stages[o->head_idx];
694 if (head == o->df_conflict_entry) {
695 df_conflict_head = 1;
699 if (remote == o->df_conflict_entry) {
700 df_conflict_remote = 1;
704 /* First, if there's a #16 situation, note that to prevent #13
707 if (!same(remote, head)) {
708 for (i = 1; i < o->head_idx; i++) {
709 if (same(stages[i], head)) {
712 if (same(stages[i], remote)) {
718 /* We start with cases where the index is allowed to match
719 * something other than the head: #14(ALT) and #2ALT, where it
720 * is permitted to match the result instead.
722 /* #14, #14ALT, #2ALT */
723 if (remote && !df_conflict_head && head_match && !remote_match) {
724 if (index && !same(index, remote) && !same(index, head))
725 return o->gently ? -1 : reject_merge(index);
726 return merged_entry(remote, index, o);
729 * If we have an entry in the index cache, then we want to
730 * make sure that it matches head.
732 if (index && !same(index, head))
733 return o->gently ? -1 : reject_merge(index);
737 if (same(head, remote))
738 return merged_entry(head, index, o);
740 if (!df_conflict_remote && remote_match && !head_match)
741 return merged_entry(head, index, o);
745 if (!head && !remote && any_anc_missing)
748 /* Under the new "aggressive" rule, we resolve mostly trivial
749 * cases that we historically had git-merge-one-file resolve.
752 int head_deleted = !head && !df_conflict_head;
753 int remote_deleted = !remote && !df_conflict_remote;
754 struct cache_entry *ce = NULL;
763 for (i = 1; i < o->head_idx; i++) {
764 if (stages[i] && stages[i] != o->df_conflict_entry) {
773 * Deleted in one and unchanged in the other.
775 if ((head_deleted && remote_deleted) ||
776 (head_deleted && remote && remote_match) ||
777 (remote_deleted && head && head_match)) {
779 return deleted_entry(index, index, o);
780 if (ce && !head_deleted) {
781 if (verify_absent(ce, "removed", o))
787 * Added in both, identically.
789 if (no_anc_exists && head && remote && same(head, remote))
790 return merged_entry(head, index, o);
794 /* Below are "no merge" cases, which require that the index be
795 * up-to-date to avoid the files getting overwritten with
796 * conflict resolution files.
799 if (verify_uptodate(index, o))
803 o->nontrivial_merge = 1;
805 /* #2, #3, #4, #6, #7, #9, #10, #11. */
807 if (!head_match || !remote_match) {
808 for (i = 1; i < o->head_idx; i++) {
809 if (stages[i] && stages[i] != o->df_conflict_entry) {
810 keep_entry(stages[i], o);
818 fprintf(stderr, "read-tree: warning #16 detected\n");
819 show_stage_entry(stderr, "head ", stages[head_match]);
820 show_stage_entry(stderr, "remote ", stages[remote_match]);
823 if (head) { count += keep_entry(head, o); }
824 if (remote) { count += keep_entry(remote, o); }
831 * The rule is to "carry forward" what is in the index without losing
832 * information across a "fast forward", favoring a successful merge
833 * over a merge failure when it makes sense. For details of the
834 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
837 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
839 struct cache_entry *current = src[0];
840 struct cache_entry *oldtree = src[1];
841 struct cache_entry *newtree = src[2];
843 if (o->merge_size != 2)
844 return error("Cannot do a twoway merge of %d trees",
847 if (oldtree == o->df_conflict_entry)
849 if (newtree == o->df_conflict_entry)
853 if ((!oldtree && !newtree) || /* 4 and 5 */
854 (!oldtree && newtree &&
855 same(current, newtree)) || /* 6 and 7 */
856 (oldtree && newtree &&
857 same(oldtree, newtree)) || /* 14 and 15 */
858 (oldtree && newtree &&
859 !same(oldtree, newtree) && /* 18 and 19 */
860 same(current, newtree))) {
861 return keep_entry(current, o);
863 else if (oldtree && !newtree && same(current, oldtree)) {
865 return deleted_entry(oldtree, current, o);
867 else if (oldtree && newtree &&
868 same(current, oldtree) && !same(current, newtree)) {
870 return merged_entry(newtree, current, o);
873 /* all other failures */
875 return o->gently ? -1 : reject_merge(oldtree);
877 return o->gently ? -1 : reject_merge(current);
879 return o->gently ? -1 : reject_merge(newtree);
884 return merged_entry(newtree, current, o);
885 return deleted_entry(oldtree, current, o);
891 * Keep the index entries at stage0, collapse stage1 but make sure
892 * stage0 does not have anything there.
894 int bind_merge(struct cache_entry **src,
895 struct unpack_trees_options *o)
897 struct cache_entry *old = src[0];
898 struct cache_entry *a = src[1];
900 if (o->merge_size != 1)
901 return error("Cannot do a bind merge of %d trees\n",
904 return o->gently ? -1 :
905 error("Entry '%s' overlaps with '%s'. Cannot bind.", a->name, old->name);
907 return keep_entry(old, o);
909 return merged_entry(a, NULL, o);
916 * - take the stat information from stage0, take the data from stage1
918 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
920 struct cache_entry *old = src[0];
921 struct cache_entry *a = src[1];
923 if (o->merge_size != 1)
924 return error("Cannot do a oneway merge of %d trees",
928 return deleted_entry(old, old, o);
930 if (old && same(old, a)) {
934 if (lstat(old->name, &st) ||
935 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID))
938 add_entry(o, old, update, 0);
941 return merged_entry(a, old, o);