1 #define NO_THE_INDEX_COMPATIBILITY_MACROS
6 #include "cache-tree.h"
7 #include "unpack-trees.h"
12 * Error messages expected by scripts out of plumbing commands such as
13 * read-tree. Non-scripted Porcelain is not required to use these messages
14 * and in fact are encouraged to reword them to better suit their particular
15 * situation better. See how "git checkout" replaces not_uptodate_file to
16 * explain why it does not allow switching between branches when you have
17 * local changes, for example.
19 static struct unpack_trees_error_msgs unpack_plumbing_errors = {
21 "Entry '%s' would be overwritten by merge. Cannot merge.",
23 /* not_uptodate_file */
24 "Entry '%s' not uptodate. Cannot merge.",
26 /* not_uptodate_dir */
27 "Updating '%s' would lose untracked files in it",
29 /* would_lose_untracked */
30 "Untracked working tree file '%s' would be %s by merge.",
33 "Entry '%s' overlaps with '%s'. Cannot bind.",
36 #define ERRORMSG(o,fld) \
37 ( ((o) && (o)->msgs.fld) \
39 : (unpack_plumbing_errors.fld) )
41 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
42 unsigned int set, unsigned int clear)
44 unsigned int size = ce_size(ce);
45 struct cache_entry *new = xmalloc(size);
47 clear |= CE_HASHED | CE_UNHASHED;
49 memcpy(new, ce, size);
51 new->ce_flags = (new->ce_flags & ~clear) | set;
52 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|ADD_CACHE_SKIP_DFCHECK);
56 * Unlink the last component and schedule the leading directories for
57 * removal, such that empty directories get removed.
59 static void unlink_entry(struct cache_entry *ce)
61 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
65 schedule_dir_for_removal(ce->name, ce_namelen(ce));
68 static struct checkout state;
69 static int check_updates(struct unpack_trees_options *o)
71 unsigned cnt = 0, total = 0;
72 struct progress *progress = NULL;
73 struct index_state *index = &o->result;
77 if (o->update && o->verbose_update) {
78 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
79 struct cache_entry *ce = index->cache[cnt];
80 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE))
84 progress = start_progress_delay("Checking out files",
89 for (i = 0; i < index->cache_nr; i++) {
90 struct cache_entry *ce = index->cache[i];
92 if (ce->ce_flags & CE_REMOVE) {
93 display_progress(progress, ++cnt);
98 remove_marked_cache_entries(&o->result);
99 remove_scheduled_dirs();
101 for (i = 0; i < index->cache_nr; i++) {
102 struct cache_entry *ce = index->cache[i];
104 if (ce->ce_flags & CE_UPDATE) {
105 display_progress(progress, ++cnt);
106 ce->ce_flags &= ~CE_UPDATE;
108 errs |= checkout_entry(ce, &state, NULL);
112 stop_progress(&progress);
116 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
118 int ret = o->fn(src, o);
124 static int unpack_index_entry(struct cache_entry *ce, struct unpack_trees_options *o)
126 struct cache_entry *src[5] = { ce, };
130 if (o->skip_unmerged) {
131 add_entry(o, ce, 0, 0);
135 return call_unpack_fn(src, o);
138 int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
141 struct tree_desc t[MAX_UNPACK_TREES];
142 struct traverse_info newinfo;
143 struct name_entry *p;
152 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
153 newinfo.conflicts |= df_conflicts;
155 for (i = 0; i < n; i++, dirmask >>= 1) {
156 const unsigned char *sha1 = NULL;
158 sha1 = names[i].sha1;
159 fill_tree_descriptor(t+i, sha1);
161 return traverse_trees(n, t, &newinfo);
165 * Compare the traverse-path to the cache entry without actually
166 * having to generate the textual representation of the traverse
169 * NOTE! This *only* compares up to the size of the traverse path
170 * itself - the caller needs to do the final check for the cache
171 * entry having more data at the end!
173 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
175 int len, pathlen, ce_len;
179 int cmp = do_compare_entry(ce, info->prev, &info->name);
183 pathlen = info->pathlen;
184 ce_len = ce_namelen(ce);
186 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
187 if (ce_len < pathlen)
191 ce_name = ce->name + pathlen;
193 len = tree_entry_len(n->path, n->sha1);
194 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
197 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
199 int cmp = do_compare_entry(ce, info, n);
204 * Even if the beginning compared identically, the ce should
205 * compare as bigger than a directory leading up to it!
207 return ce_namelen(ce) > traverse_path_len(info, n);
210 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
212 int len = traverse_path_len(info, n);
213 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
215 ce->ce_mode = create_ce_mode(n->mode);
216 ce->ce_flags = create_ce_flags(len, stage);
217 hashcpy(ce->sha1, n->sha1);
218 make_traverse_path(ce->name, info, n);
223 static int unpack_nondirectories(int n, unsigned long mask,
224 unsigned long dirmask,
225 struct cache_entry **src,
226 const struct name_entry *names,
227 const struct traverse_info *info)
230 struct unpack_trees_options *o = info->data;
231 unsigned long conflicts;
233 /* Do we have *only* directories? Nothing to do */
234 if (mask == dirmask && !src[0])
237 conflicts = info->conflicts;
240 conflicts |= dirmask;
243 * Ok, we've filled in up to any potential index entry in src[0],
246 for (i = 0; i < n; i++) {
248 unsigned int bit = 1ul << i;
249 if (conflicts & bit) {
250 src[i + o->merge] = o->df_conflict_entry;
257 else if (i + 1 < o->head_idx)
259 else if (i + 1 > o->head_idx)
263 src[i + o->merge] = create_ce_entry(info, names + i, stage);
267 return call_unpack_fn(src, o);
270 for (i = 0; i < n; i++)
271 add_entry(o, src[i], 0, 0);
275 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
277 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
278 struct unpack_trees_options *o = info->data;
279 const struct name_entry *p = names;
281 /* Find first entry with a real name (we could use "mask" too) */
285 /* Are we supposed to look at the index too? */
287 while (o->pos < o->src_index->cache_nr) {
288 struct cache_entry *ce = o->src_index->cache[o->pos];
289 int cmp = compare_entry(ce, info, p);
291 if (unpack_index_entry(ce, o) < 0)
299 * If we skip unmerged index entries, we'll skip this
300 * entry *and* the tree entries associated with it!
302 if (o->skip_unmerged) {
303 add_entry(o, ce, 0, 0);
313 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
316 /* Now handle any directories.. */
318 unsigned long conflicts = mask & ~dirmask;
324 if (traverse_trees_recursive(n, dirmask, conflicts,
333 static int unpack_failed(struct unpack_trees_options *o, const char *message)
335 discard_index(&o->result);
338 return error("%s", message);
345 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
346 * resulting index, -2 on failure to reflect the changes to the work tree.
348 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
351 static struct cache_entry *dfc;
353 if (len > MAX_UNPACK_TREES)
354 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
355 memset(&state, 0, sizeof(state));
359 state.refresh_cache = 1;
361 memset(&o->result, 0, sizeof(o->result));
362 o->result.initialized = 1;
364 o->result.timestamp = o->src_index->timestamp;
368 dfc = xcalloc(1, cache_entry_size(0));
369 o->df_conflict_entry = dfc;
372 const char *prefix = o->prefix ? o->prefix : "";
373 struct traverse_info info;
375 setup_traverse_info(&info, prefix);
376 info.fn = unpack_callback;
379 if (traverse_trees(len, t, &info) < 0)
380 return unpack_failed(o, NULL);
383 /* Any left-over entries in the index? */
385 while (o->pos < o->src_index->cache_nr) {
386 struct cache_entry *ce = o->src_index->cache[o->pos];
387 if (unpack_index_entry(ce, o) < 0)
388 return unpack_failed(o, NULL);
392 if (o->trivial_merges_only && o->nontrivial_merge)
393 return unpack_failed(o, "Merge requires file-level merging");
396 ret = check_updates(o) ? (-2) : 0;
398 *o->dst_index = o->result;
402 /* Here come the merge functions */
404 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
406 return error(ERRORMSG(o, would_overwrite), ce->name);
409 static int same(struct cache_entry *a, struct cache_entry *b)
415 return a->ce_mode == b->ce_mode &&
416 !hashcmp(a->sha1, b->sha1);
421 * When a CE gets turned into an unmerged entry, we
422 * want it to be up-to-date
424 static int verify_uptodate(struct cache_entry *ce,
425 struct unpack_trees_options *o)
429 if (o->index_only || o->reset)
432 if (!lstat(ce->name, &st)) {
433 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID);
437 * NEEDSWORK: the current default policy is to allow
438 * submodule to be out of sync wrt the supermodule
439 * index. This needs to be tightened later for
440 * submodules that are marked to be automatically
443 if (S_ISGITLINK(ce->ce_mode))
449 return o->gently ? -1 :
450 error(ERRORMSG(o, not_uptodate_file), ce->name);
453 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
456 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
460 * Check that checking out ce->sha1 in subdir ce->name is not
461 * going to overwrite any working files.
463 * Currently, git does not checkout subprojects during a superproject
464 * checkout, so it is not going to overwrite anything.
466 static int verify_clean_submodule(struct cache_entry *ce, const char *action,
467 struct unpack_trees_options *o)
472 static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
473 struct unpack_trees_options *o)
476 * we are about to extract "ce->name"; we would not want to lose
477 * anything in the existing directory there.
484 unsigned char sha1[20];
486 if (S_ISGITLINK(ce->ce_mode) &&
487 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
488 /* If we are not going to update the submodule, then
491 if (!hashcmp(sha1, ce->sha1))
493 return verify_clean_submodule(ce, action, o);
497 * First let's make sure we do not have a local modification
500 namelen = strlen(ce->name);
501 for (i = o->pos; i < o->src_index->cache_nr; i++) {
502 struct cache_entry *ce2 = o->src_index->cache[i];
503 int len = ce_namelen(ce2);
505 strncmp(ce->name, ce2->name, namelen) ||
506 ce2->name[namelen] != '/')
509 * ce2->name is an entry in the subdirectory.
511 if (!ce_stage(ce2)) {
512 if (verify_uptodate(ce2, o))
514 add_entry(o, ce2, CE_REMOVE, 0);
520 * Then we need to make sure that we do not lose a locally
521 * present file that is not ignored.
523 pathbuf = xmalloc(namelen + 2);
524 memcpy(pathbuf, ce->name, namelen);
525 strcpy(pathbuf+namelen, "/");
527 memset(&d, 0, sizeof(d));
529 d.exclude_per_dir = o->dir->exclude_per_dir;
530 i = read_directory(&d, ce->name, pathbuf, namelen+1, NULL);
532 return o->gently ? -1 :
533 error(ERRORMSG(o, not_uptodate_dir), ce->name);
539 * This gets called when there was no index entry for the tree entry 'dst',
540 * but we found a file in the working tree that 'lstat()' said was fine,
541 * and we're on a case-insensitive filesystem.
543 * See if we can find a case-insensitive match in the index that also
544 * matches the stat information, and assume it's that other file!
546 static int icase_exists(struct unpack_trees_options *o, struct cache_entry *dst, struct stat *st)
548 struct cache_entry *src;
550 src = index_name_exists(o->src_index, dst->name, ce_namelen(dst), 1);
551 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID);
555 * We do not want to remove or overwrite a working tree file that
556 * is not tracked, unless it is ignored.
558 static int verify_absent(struct cache_entry *ce, const char *action,
559 struct unpack_trees_options *o)
563 if (o->index_only || o->reset || !o->update)
566 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
569 if (!lstat(ce->name, &st)) {
571 int dtype = ce_to_dtype(ce);
572 struct cache_entry *result;
575 * It may be that the 'lstat()' succeeded even though
576 * target 'ce' was absent, because there is an old
577 * entry that is different only in case..
579 * Ignore that lstat() if it matches.
581 if (ignore_case && icase_exists(o, ce, &st))
584 if (o->dir && excluded(o->dir, ce->name, &dtype))
586 * ce->name is explicitly excluded, so it is Ok to
590 if (S_ISDIR(st.st_mode)) {
592 * We are checking out path "foo" and
593 * found "foo/." in the working tree.
594 * This is tricky -- if we have modified
595 * files that are in "foo/" we would lose
598 ret = verify_clean_subdirectory(ce, action, o);
603 * If this removed entries from the index,
604 * what that means is:
606 * (1) the caller unpack_callback() saw path/foo
607 * in the index, and it has not removed it because
608 * it thinks it is handling 'path' as blob with
610 * (2) we will return "ok, we placed a merged entry
611 * in the index" which would cause o->pos to be
612 * incremented by one;
613 * (3) however, original o->pos now has 'path/foo'
614 * marked with "to be removed".
616 * We need to increment it by the number of
617 * deleted entries here.
624 * The previous round may already have decided to
625 * delete this path, which is in a subdirectory that
626 * is being replaced with a blob.
628 result = index_name_exists(&o->result, ce->name, ce_namelen(ce), 0);
630 if (result->ce_flags & CE_REMOVE)
634 return o->gently ? -1 :
635 error(ERRORMSG(o, would_lose_untracked), ce->name, action);
640 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
641 struct unpack_trees_options *o)
643 int update = CE_UPDATE;
647 * See if we can re-use the old CE directly?
648 * That way we get the uptodate stat info.
650 * This also removes the UPDATE flag on a match; otherwise
651 * we will end up overwriting local changes in the work tree.
653 if (same(old, merge)) {
654 copy_cache_entry(merge, old);
657 if (verify_uptodate(old, o))
659 invalidate_ce_path(old, o);
663 if (verify_absent(merge, "overwritten", o))
665 invalidate_ce_path(merge, o);
668 add_entry(o, merge, update, CE_STAGEMASK);
672 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
673 struct unpack_trees_options *o)
675 /* Did it exist in the index? */
677 if (verify_absent(ce, "removed", o))
681 if (verify_uptodate(old, o))
683 add_entry(o, ce, CE_REMOVE, 0);
684 invalidate_ce_path(ce, o);
688 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
690 add_entry(o, ce, 0, 0);
695 static void show_stage_entry(FILE *o,
696 const char *label, const struct cache_entry *ce)
699 fprintf(o, "%s (missing)\n", label);
701 fprintf(o, "%s%06o %s %d\t%s\n",
704 sha1_to_hex(ce->sha1),
710 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
712 struct cache_entry *index;
713 struct cache_entry *head;
714 struct cache_entry *remote = stages[o->head_idx + 1];
717 int remote_match = 0;
719 int df_conflict_head = 0;
720 int df_conflict_remote = 0;
722 int any_anc_missing = 0;
723 int no_anc_exists = 1;
726 for (i = 1; i < o->head_idx; i++) {
727 if (!stages[i] || stages[i] == o->df_conflict_entry)
734 head = stages[o->head_idx];
736 if (head == o->df_conflict_entry) {
737 df_conflict_head = 1;
741 if (remote == o->df_conflict_entry) {
742 df_conflict_remote = 1;
746 /* First, if there's a #16 situation, note that to prevent #13
749 if (!same(remote, head)) {
750 for (i = 1; i < o->head_idx; i++) {
751 if (same(stages[i], head)) {
754 if (same(stages[i], remote)) {
760 /* We start with cases where the index is allowed to match
761 * something other than the head: #14(ALT) and #2ALT, where it
762 * is permitted to match the result instead.
764 /* #14, #14ALT, #2ALT */
765 if (remote && !df_conflict_head && head_match && !remote_match) {
766 if (index && !same(index, remote) && !same(index, head))
767 return o->gently ? -1 : reject_merge(index, o);
768 return merged_entry(remote, index, o);
771 * If we have an entry in the index cache, then we want to
772 * make sure that it matches head.
774 if (index && !same(index, head))
775 return o->gently ? -1 : reject_merge(index, o);
779 if (same(head, remote))
780 return merged_entry(head, index, o);
782 if (!df_conflict_remote && remote_match && !head_match)
783 return merged_entry(head, index, o);
787 if (!head && !remote && any_anc_missing)
790 /* Under the new "aggressive" rule, we resolve mostly trivial
791 * cases that we historically had git-merge-one-file resolve.
794 int head_deleted = !head && !df_conflict_head;
795 int remote_deleted = !remote && !df_conflict_remote;
796 struct cache_entry *ce = NULL;
805 for (i = 1; i < o->head_idx; i++) {
806 if (stages[i] && stages[i] != o->df_conflict_entry) {
815 * Deleted in one and unchanged in the other.
817 if ((head_deleted && remote_deleted) ||
818 (head_deleted && remote && remote_match) ||
819 (remote_deleted && head && head_match)) {
821 return deleted_entry(index, index, o);
822 if (ce && !head_deleted) {
823 if (verify_absent(ce, "removed", o))
829 * Added in both, identically.
831 if (no_anc_exists && head && remote && same(head, remote))
832 return merged_entry(head, index, o);
836 /* Below are "no merge" cases, which require that the index be
837 * up-to-date to avoid the files getting overwritten with
838 * conflict resolution files.
841 if (verify_uptodate(index, o))
845 o->nontrivial_merge = 1;
847 /* #2, #3, #4, #6, #7, #9, #10, #11. */
849 if (!head_match || !remote_match) {
850 for (i = 1; i < o->head_idx; i++) {
851 if (stages[i] && stages[i] != o->df_conflict_entry) {
852 keep_entry(stages[i], o);
860 fprintf(stderr, "read-tree: warning #16 detected\n");
861 show_stage_entry(stderr, "head ", stages[head_match]);
862 show_stage_entry(stderr, "remote ", stages[remote_match]);
865 if (head) { count += keep_entry(head, o); }
866 if (remote) { count += keep_entry(remote, o); }
873 * The rule is to "carry forward" what is in the index without losing
874 * information across a "fast forward", favoring a successful merge
875 * over a merge failure when it makes sense. For details of the
876 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
879 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
881 struct cache_entry *current = src[0];
882 struct cache_entry *oldtree = src[1];
883 struct cache_entry *newtree = src[2];
885 if (o->merge_size != 2)
886 return error("Cannot do a twoway merge of %d trees",
889 if (oldtree == o->df_conflict_entry)
891 if (newtree == o->df_conflict_entry)
895 if ((!oldtree && !newtree) || /* 4 and 5 */
896 (!oldtree && newtree &&
897 same(current, newtree)) || /* 6 and 7 */
898 (oldtree && newtree &&
899 same(oldtree, newtree)) || /* 14 and 15 */
900 (oldtree && newtree &&
901 !same(oldtree, newtree) && /* 18 and 19 */
902 same(current, newtree))) {
903 return keep_entry(current, o);
905 else if (oldtree && !newtree && same(current, oldtree)) {
907 return deleted_entry(oldtree, current, o);
909 else if (oldtree && newtree &&
910 same(current, oldtree) && !same(current, newtree)) {
912 return merged_entry(newtree, current, o);
915 /* all other failures */
917 return o->gently ? -1 : reject_merge(oldtree, o);
919 return o->gently ? -1 : reject_merge(current, o);
921 return o->gently ? -1 : reject_merge(newtree, o);
926 if (oldtree && !o->initial_checkout) {
928 * deletion of the path was staged;
930 if (same(oldtree, newtree))
932 return reject_merge(oldtree, o);
934 return merged_entry(newtree, current, o);
936 return deleted_entry(oldtree, current, o);
942 * Keep the index entries at stage0, collapse stage1 but make sure
943 * stage0 does not have anything there.
945 int bind_merge(struct cache_entry **src,
946 struct unpack_trees_options *o)
948 struct cache_entry *old = src[0];
949 struct cache_entry *a = src[1];
951 if (o->merge_size != 1)
952 return error("Cannot do a bind merge of %d trees\n",
955 return o->gently ? -1 :
956 error(ERRORMSG(o, bind_overlap), a->name, old->name);
958 return keep_entry(old, o);
960 return merged_entry(a, NULL, o);
967 * - take the stat information from stage0, take the data from stage1
969 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
971 struct cache_entry *old = src[0];
972 struct cache_entry *a = src[1];
974 if (o->merge_size != 1)
975 return error("Cannot do a oneway merge of %d trees",
979 return deleted_entry(old, old, o);
981 if (old && same(old, a)) {
985 if (lstat(old->name, &st) ||
986 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID))
989 add_entry(o, old, update, 0);
992 return merged_entry(a, old, o);