blame.c: Properly initialize strbuf after calling, textconv_object()
[git/dscho.git] / unpack-trees.c
blobf561d88156b827b15bad7dd4e00f944718149bd9
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.",
36 /* sparse_not_uptodate_file */
37 "Entry '%s' not uptodate. Cannot update sparse checkout.",
39 /* would_lose_orphaned */
40 "Working tree file '%s' would be %s by sparse checkout update.",
43 #define ERRORMSG(o,fld) \
44 ( ((o) && (o)->msgs.fld) \
45 ? ((o)->msgs.fld) \
46 : (unpack_plumbing_errors.fld) )
48 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
49 unsigned int set, unsigned int clear)
51 unsigned int size = ce_size(ce);
52 struct cache_entry *new = xmalloc(size);
54 clear |= CE_HASHED | CE_UNHASHED;
56 memcpy(new, ce, size);
57 new->next = NULL;
58 new->ce_flags = (new->ce_flags & ~clear) | set;
59 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
63 * Unlink the last component and schedule the leading directories for
64 * removal, such that empty directories get removed.
66 static void unlink_entry(struct cache_entry *ce)
68 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
69 return;
70 if (remove_or_warn(ce->ce_mode, ce->name))
71 return;
72 schedule_dir_for_removal(ce->name, ce_namelen(ce));
75 static struct checkout state;
76 static int check_updates(struct unpack_trees_options *o)
78 unsigned cnt = 0, total = 0;
79 struct progress *progress = NULL;
80 struct index_state *index = &o->result;
81 int i;
82 int errs = 0;
84 if (o->update && o->verbose_update) {
85 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
86 struct cache_entry *ce = index->cache[cnt];
87 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE | CE_WT_REMOVE))
88 total++;
91 progress = start_progress_delay("Checking out files",
92 total, 50, 1);
93 cnt = 0;
96 if (o->update)
97 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
98 for (i = 0; i < index->cache_nr; i++) {
99 struct cache_entry *ce = index->cache[i];
101 if (ce->ce_flags & CE_WT_REMOVE) {
102 display_progress(progress, ++cnt);
103 if (o->update)
104 unlink_entry(ce);
105 continue;
108 if (ce->ce_flags & CE_REMOVE) {
109 display_progress(progress, ++cnt);
110 if (o->update)
111 unlink_entry(ce);
114 remove_marked_cache_entries(&o->result);
115 remove_scheduled_dirs();
117 for (i = 0; i < index->cache_nr; i++) {
118 struct cache_entry *ce = index->cache[i];
120 if (ce->ce_flags & CE_UPDATE) {
121 display_progress(progress, ++cnt);
122 ce->ce_flags &= ~CE_UPDATE;
123 if (o->update) {
124 errs |= checkout_entry(ce, &state, NULL);
128 stop_progress(&progress);
129 if (o->update)
130 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
131 return errs != 0;
134 static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
135 static int verify_absent_sparse(struct cache_entry *ce, const char *action, struct unpack_trees_options *o);
137 static int will_have_skip_worktree(const struct cache_entry *ce, struct unpack_trees_options *o)
139 const char *basename;
141 if (ce_stage(ce))
142 return 0;
144 basename = strrchr(ce->name, '/');
145 basename = basename ? basename+1 : ce->name;
146 return excluded_from_list(ce->name, ce_namelen(ce), basename, NULL, o->el) <= 0;
149 static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
151 int was_skip_worktree = ce_skip_worktree(ce);
153 if (will_have_skip_worktree(ce, o))
154 ce->ce_flags |= CE_SKIP_WORKTREE;
155 else
156 ce->ce_flags &= ~CE_SKIP_WORKTREE;
159 * We only care about files getting into the checkout area
160 * If merge strategies want to remove some, go ahead, this
161 * flag will be removed eventually in unpack_trees() if it's
162 * outside checkout area.
164 if (ce->ce_flags & CE_REMOVE)
165 return 0;
167 if (!was_skip_worktree && ce_skip_worktree(ce)) {
169 * If CE_UPDATE is set, verify_uptodate() must be called already
170 * also stat info may have lost after merged_entry() so calling
171 * verify_uptodate() again may fail
173 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
174 return -1;
175 ce->ce_flags |= CE_WT_REMOVE;
177 if (was_skip_worktree && !ce_skip_worktree(ce)) {
178 if (verify_absent_sparse(ce, "overwritten", o))
179 return -1;
180 ce->ce_flags |= CE_UPDATE;
182 return 0;
185 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
187 int ret = o->fn(src, o);
188 if (ret > 0)
189 ret = 0;
190 return ret;
193 static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
195 ce->ce_flags |= CE_UNPACKED;
197 if (o->cache_bottom < o->src_index->cache_nr &&
198 o->src_index->cache[o->cache_bottom] == ce) {
199 int bottom = o->cache_bottom;
200 while (bottom < o->src_index->cache_nr &&
201 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
202 bottom++;
203 o->cache_bottom = bottom;
207 static void mark_all_ce_unused(struct index_state *index)
209 int i;
210 for (i = 0; i < index->cache_nr; i++)
211 index->cache[i]->ce_flags &= ~CE_UNPACKED;
214 static int locate_in_src_index(struct cache_entry *ce,
215 struct unpack_trees_options *o)
217 struct index_state *index = o->src_index;
218 int len = ce_namelen(ce);
219 int pos = index_name_pos(index, ce->name, len);
220 if (pos < 0)
221 pos = -1 - pos;
222 return pos;
226 * We call unpack_index_entry() with an unmerged cache entry
227 * only in diff-index, and it wants a single callback. Skip
228 * the other unmerged entry with the same name.
230 static void mark_ce_used_same_name(struct cache_entry *ce,
231 struct unpack_trees_options *o)
233 struct index_state *index = o->src_index;
234 int len = ce_namelen(ce);
235 int pos;
237 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
238 struct cache_entry *next = index->cache[pos];
239 if (len != ce_namelen(next) ||
240 memcmp(ce->name, next->name, len))
241 break;
242 mark_ce_used(next, o);
246 static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
248 const struct index_state *index = o->src_index;
249 int pos = o->cache_bottom;
251 while (pos < index->cache_nr) {
252 struct cache_entry *ce = index->cache[pos];
253 if (!(ce->ce_flags & CE_UNPACKED))
254 return ce;
255 pos++;
257 return NULL;
260 static void add_same_unmerged(struct cache_entry *ce,
261 struct unpack_trees_options *o)
263 struct index_state *index = o->src_index;
264 int len = ce_namelen(ce);
265 int pos = index_name_pos(index, ce->name, len);
267 if (0 <= pos)
268 die("programming error in a caller of mark_ce_used_same_name");
269 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
270 struct cache_entry *next = index->cache[pos];
271 if (len != ce_namelen(next) ||
272 memcmp(ce->name, next->name, len))
273 break;
274 add_entry(o, next, 0, 0);
275 mark_ce_used(next, o);
279 static int unpack_index_entry(struct cache_entry *ce,
280 struct unpack_trees_options *o)
282 struct cache_entry *src[5] = { NULL };
283 int ret;
285 src[0] = ce;
287 mark_ce_used(ce, o);
288 if (ce_stage(ce)) {
289 if (o->skip_unmerged) {
290 add_entry(o, ce, 0, 0);
291 return 0;
294 ret = call_unpack_fn(src, o);
295 if (ce_stage(ce))
296 mark_ce_used_same_name(ce, o);
297 return ret;
300 static int find_cache_pos(struct traverse_info *, const struct name_entry *);
302 static void restore_cache_bottom(struct traverse_info *info, int bottom)
304 struct unpack_trees_options *o = info->data;
306 if (o->diff_index_cached)
307 return;
308 o->cache_bottom = bottom;
311 static int switch_cache_bottom(struct traverse_info *info)
313 struct unpack_trees_options *o = info->data;
314 int ret, pos;
316 if (o->diff_index_cached)
317 return 0;
318 ret = o->cache_bottom;
319 pos = find_cache_pos(info->prev, &info->name);
321 if (pos < -1)
322 o->cache_bottom = -2 - pos;
323 else if (pos < 0)
324 o->cache_bottom = o->src_index->cache_nr;
325 return ret;
328 static int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
330 int i, ret, bottom;
331 struct tree_desc t[MAX_UNPACK_TREES];
332 void *buf[MAX_UNPACK_TREES];
333 struct traverse_info newinfo;
334 struct name_entry *p;
336 p = names;
337 while (!p->mode)
338 p++;
340 newinfo = *info;
341 newinfo.prev = info;
342 newinfo.name = *p;
343 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
344 newinfo.conflicts |= df_conflicts;
346 for (i = 0; i < n; i++, dirmask >>= 1) {
347 const unsigned char *sha1 = NULL;
348 if (dirmask & 1)
349 sha1 = names[i].sha1;
350 buf[i] = fill_tree_descriptor(t+i, sha1);
353 bottom = switch_cache_bottom(&newinfo);
354 ret = traverse_trees(n, t, &newinfo);
355 restore_cache_bottom(&newinfo, bottom);
357 for (i = 0; i < n; i++)
358 free(buf[i]);
360 return ret;
364 * Compare the traverse-path to the cache entry without actually
365 * having to generate the textual representation of the traverse
366 * path.
368 * NOTE! This *only* compares up to the size of the traverse path
369 * itself - the caller needs to do the final check for the cache
370 * entry having more data at the end!
372 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
374 int len, pathlen, ce_len;
375 const char *ce_name;
377 if (info->prev) {
378 int cmp = do_compare_entry(ce, info->prev, &info->name);
379 if (cmp)
380 return cmp;
382 pathlen = info->pathlen;
383 ce_len = ce_namelen(ce);
385 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
386 if (ce_len < pathlen)
387 return -1;
389 ce_len -= pathlen;
390 ce_name = ce->name + pathlen;
392 len = tree_entry_len(n->path, n->sha1);
393 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
396 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
398 int cmp = do_compare_entry(ce, info, n);
399 if (cmp)
400 return cmp;
403 * Even if the beginning compared identically, the ce should
404 * compare as bigger than a directory leading up to it!
406 return ce_namelen(ce) > traverse_path_len(info, n);
409 static int ce_in_traverse_path(const struct cache_entry *ce,
410 const struct traverse_info *info)
412 if (!info->prev)
413 return 1;
414 if (do_compare_entry(ce, info->prev, &info->name))
415 return 0;
417 * If ce (blob) is the same name as the path (which is a tree
418 * we will be descending into), it won't be inside it.
420 return (info->pathlen < ce_namelen(ce));
423 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
425 int len = traverse_path_len(info, n);
426 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
428 ce->ce_mode = create_ce_mode(n->mode);
429 ce->ce_flags = create_ce_flags(len, stage);
430 hashcpy(ce->sha1, n->sha1);
431 make_traverse_path(ce->name, info, n);
433 return ce;
436 static int unpack_nondirectories(int n, unsigned long mask,
437 unsigned long dirmask,
438 struct cache_entry **src,
439 const struct name_entry *names,
440 const struct traverse_info *info)
442 int i;
443 struct unpack_trees_options *o = info->data;
444 unsigned long conflicts;
446 /* Do we have *only* directories? Nothing to do */
447 if (mask == dirmask && !src[0])
448 return 0;
450 conflicts = info->conflicts;
451 if (o->merge)
452 conflicts >>= 1;
453 conflicts |= dirmask;
456 * Ok, we've filled in up to any potential index entry in src[0],
457 * now do the rest.
459 for (i = 0; i < n; i++) {
460 int stage;
461 unsigned int bit = 1ul << i;
462 if (conflicts & bit) {
463 src[i + o->merge] = o->df_conflict_entry;
464 continue;
466 if (!(mask & bit))
467 continue;
468 if (!o->merge)
469 stage = 0;
470 else if (i + 1 < o->head_idx)
471 stage = 1;
472 else if (i + 1 > o->head_idx)
473 stage = 3;
474 else
475 stage = 2;
476 src[i + o->merge] = create_ce_entry(info, names + i, stage);
479 if (o->merge)
480 return call_unpack_fn(src, o);
482 for (i = 0; i < n; i++)
483 if (src[i] && src[i] != o->df_conflict_entry)
484 add_entry(o, src[i], 0, 0);
485 return 0;
488 static int unpack_failed(struct unpack_trees_options *o, const char *message)
490 discard_index(&o->result);
491 if (!o->gently) {
492 if (message)
493 return error("%s", message);
494 return -1;
496 return -1;
499 /* NEEDSWORK: give this a better name and share with tree-walk.c */
500 static int name_compare(const char *a, int a_len,
501 const char *b, int b_len)
503 int len = (a_len < b_len) ? a_len : b_len;
504 int cmp = memcmp(a, b, len);
505 if (cmp)
506 return cmp;
507 return (a_len - b_len);
511 * The tree traversal is looking at name p. If we have a matching entry,
512 * return it. If name p is a directory in the index, do not return
513 * anything, as we will want to match it when the traversal descends into
514 * the directory.
516 static int find_cache_pos(struct traverse_info *info,
517 const struct name_entry *p)
519 int pos;
520 struct unpack_trees_options *o = info->data;
521 struct index_state *index = o->src_index;
522 int pfxlen = info->pathlen;
523 int p_len = tree_entry_len(p->path, p->sha1);
525 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
526 struct cache_entry *ce = index->cache[pos];
527 const char *ce_name, *ce_slash;
528 int cmp, ce_len;
530 if (ce->ce_flags & CE_UNPACKED) {
532 * cache_bottom entry is already unpacked, so
533 * we can never match it; don't check it
534 * again.
536 if (pos == o->cache_bottom)
537 ++o->cache_bottom;
538 continue;
540 if (!ce_in_traverse_path(ce, info))
541 continue;
542 ce_name = ce->name + pfxlen;
543 ce_slash = strchr(ce_name, '/');
544 if (ce_slash)
545 ce_len = ce_slash - ce_name;
546 else
547 ce_len = ce_namelen(ce) - pfxlen;
548 cmp = name_compare(p->path, p_len, ce_name, ce_len);
550 * Exact match; if we have a directory we need to
551 * delay returning it.
553 if (!cmp)
554 return ce_slash ? -2 - pos : pos;
555 if (0 < cmp)
556 continue; /* keep looking */
558 * ce_name sorts after p->path; could it be that we
559 * have files under p->path directory in the index?
560 * E.g. ce_name == "t-i", and p->path == "t"; we may
561 * have "t/a" in the index.
563 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
564 ce_name[p_len] < '/')
565 continue; /* keep looking */
566 break;
568 return -1;
571 static struct cache_entry *find_cache_entry(struct traverse_info *info,
572 const struct name_entry *p)
574 int pos = find_cache_pos(info, p);
575 struct unpack_trees_options *o = info->data;
577 if (0 <= pos)
578 return o->src_index->cache[pos];
579 else
580 return NULL;
583 static void debug_path(struct traverse_info *info)
585 if (info->prev) {
586 debug_path(info->prev);
587 if (*info->prev->name.path)
588 putchar('/');
590 printf("%s", info->name.path);
593 static void debug_name_entry(int i, struct name_entry *n)
595 printf("ent#%d %06o %s\n", i,
596 n->path ? n->mode : 0,
597 n->path ? n->path : "(missing)");
600 static void debug_unpack_callback(int n,
601 unsigned long mask,
602 unsigned long dirmask,
603 struct name_entry *names,
604 struct traverse_info *info)
606 int i;
607 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
608 mask, dirmask, n);
609 debug_path(info);
610 putchar('\n');
611 for (i = 0; i < n; i++)
612 debug_name_entry(i, names + i);
615 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
617 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
618 struct unpack_trees_options *o = info->data;
619 const struct name_entry *p = names;
621 /* Find first entry with a real name (we could use "mask" too) */
622 while (!p->mode)
623 p++;
625 if (o->debug_unpack)
626 debug_unpack_callback(n, mask, dirmask, names, info);
628 /* Are we supposed to look at the index too? */
629 if (o->merge) {
630 while (1) {
631 int cmp;
632 struct cache_entry *ce;
634 if (o->diff_index_cached)
635 ce = next_cache_entry(o);
636 else
637 ce = find_cache_entry(info, p);
639 if (!ce)
640 break;
641 cmp = compare_entry(ce, info, p);
642 if (cmp < 0) {
643 if (unpack_index_entry(ce, o) < 0)
644 return unpack_failed(o, NULL);
645 continue;
647 if (!cmp) {
648 if (ce_stage(ce)) {
650 * If we skip unmerged index
651 * entries, we'll skip this
652 * entry *and* the tree
653 * entries associated with it!
655 if (o->skip_unmerged) {
656 add_same_unmerged(ce, o);
657 return mask;
660 src[0] = ce;
662 break;
666 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
667 return -1;
669 if (src[0]) {
670 if (ce_stage(src[0]))
671 mark_ce_used_same_name(src[0], o);
672 else
673 mark_ce_used(src[0], o);
676 /* Now handle any directories.. */
677 if (dirmask) {
678 unsigned long conflicts = mask & ~dirmask;
679 if (o->merge) {
680 conflicts <<= 1;
681 if (src[0])
682 conflicts |= 1;
685 /* special case: "diff-index --cached" looking at a tree */
686 if (o->diff_index_cached &&
687 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
688 int matches;
689 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
690 names, info);
692 * Everything under the name matches; skip the
693 * entire hierarchy. diff_index_cached codepath
694 * special cases D/F conflicts in such a way that
695 * it does not do any look-ahead, so this is safe.
697 if (matches) {
698 o->cache_bottom += matches;
699 return mask;
703 if (traverse_trees_recursive(n, dirmask, conflicts,
704 names, info) < 0)
705 return -1;
706 return mask;
709 return mask;
713 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
714 * resulting index, -2 on failure to reflect the changes to the work tree.
716 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
718 int i, ret;
719 static struct cache_entry *dfc;
720 struct exclude_list el;
722 if (len > MAX_UNPACK_TREES)
723 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
724 memset(&state, 0, sizeof(state));
725 state.base_dir = "";
726 state.force = 1;
727 state.quiet = 1;
728 state.refresh_cache = 1;
730 memset(&el, 0, sizeof(el));
731 if (!core_apply_sparse_checkout || !o->update)
732 o->skip_sparse_checkout = 1;
733 if (!o->skip_sparse_checkout) {
734 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
735 o->skip_sparse_checkout = 1;
736 else
737 o->el = &el;
740 memset(&o->result, 0, sizeof(o->result));
741 o->result.initialized = 1;
742 o->result.timestamp.sec = o->src_index->timestamp.sec;
743 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
744 o->merge_size = len;
745 mark_all_ce_unused(o->src_index);
747 if (!dfc)
748 dfc = xcalloc(1, cache_entry_size(0));
749 o->df_conflict_entry = dfc;
751 if (len) {
752 const char *prefix = o->prefix ? o->prefix : "";
753 struct traverse_info info;
755 setup_traverse_info(&info, prefix);
756 info.fn = unpack_callback;
757 info.data = o;
759 if (o->prefix) {
761 * Unpack existing index entries that sort before the
762 * prefix the tree is spliced into. Note that o->merge
763 * is always true in this case.
765 while (1) {
766 struct cache_entry *ce = next_cache_entry(o);
767 if (!ce)
768 break;
769 if (ce_in_traverse_path(ce, &info))
770 break;
771 if (unpack_index_entry(ce, o) < 0)
772 goto return_failed;
776 if (traverse_trees(len, t, &info) < 0)
777 goto return_failed;
780 /* Any left-over entries in the index? */
781 if (o->merge) {
782 while (1) {
783 struct cache_entry *ce = next_cache_entry(o);
784 if (!ce)
785 break;
786 if (unpack_index_entry(ce, o) < 0)
787 goto return_failed;
790 mark_all_ce_unused(o->src_index);
792 if (o->trivial_merges_only && o->nontrivial_merge) {
793 ret = unpack_failed(o, "Merge requires file-level merging");
794 goto done;
797 if (!o->skip_sparse_checkout) {
798 int empty_worktree = 1;
799 for (i = 0;i < o->result.cache_nr;i++) {
800 struct cache_entry *ce = o->result.cache[i];
802 if (apply_sparse_checkout(ce, o)) {
803 ret = -1;
804 goto done;
807 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
808 * area as a result of ce_skip_worktree() shortcuts in
809 * verify_absent() and verify_uptodate(). Clear them.
811 if (ce_skip_worktree(ce))
812 ce->ce_flags &= ~(CE_UPDATE | CE_REMOVE);
813 else
814 empty_worktree = 0;
817 if (o->result.cache_nr && empty_worktree) {
818 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
819 goto done;
823 o->src_index = NULL;
824 ret = check_updates(o) ? (-2) : 0;
825 if (o->dst_index)
826 *o->dst_index = o->result;
828 done:
829 for (i = 0;i < el.nr;i++)
830 free(el.excludes[i]);
831 if (el.excludes)
832 free(el.excludes);
834 return ret;
836 return_failed:
837 mark_all_ce_unused(o->src_index);
838 ret = unpack_failed(o, NULL);
839 goto done;
842 /* Here come the merge functions */
844 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
846 return error(ERRORMSG(o, would_overwrite), ce->name);
849 static int same(struct cache_entry *a, struct cache_entry *b)
851 if (!!a != !!b)
852 return 0;
853 if (!a && !b)
854 return 1;
855 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
856 return 0;
857 return a->ce_mode == b->ce_mode &&
858 !hashcmp(a->sha1, b->sha1);
863 * When a CE gets turned into an unmerged entry, we
864 * want it to be up-to-date
866 static int verify_uptodate_1(struct cache_entry *ce,
867 struct unpack_trees_options *o,
868 const char *error_msg)
870 struct stat st;
872 if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
873 return 0;
875 if (!lstat(ce->name, &st)) {
876 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
877 if (!changed)
878 return 0;
880 * NEEDSWORK: the current default policy is to allow
881 * submodule to be out of sync wrt the supermodule
882 * index. This needs to be tightened later for
883 * submodules that are marked to be automatically
884 * checked out.
886 if (S_ISGITLINK(ce->ce_mode))
887 return 0;
888 errno = 0;
890 if (errno == ENOENT)
891 return 0;
892 return o->gently ? -1 :
893 error(error_msg, ce->name);
896 static int verify_uptodate(struct cache_entry *ce,
897 struct unpack_trees_options *o)
899 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
900 return 0;
901 return verify_uptodate_1(ce, o, ERRORMSG(o, not_uptodate_file));
904 static int verify_uptodate_sparse(struct cache_entry *ce,
905 struct unpack_trees_options *o)
907 return verify_uptodate_1(ce, o, ERRORMSG(o, sparse_not_uptodate_file));
910 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
912 if (ce)
913 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
917 * Check that checking out ce->sha1 in subdir ce->name is not
918 * going to overwrite any working files.
920 * Currently, git does not checkout subprojects during a superproject
921 * checkout, so it is not going to overwrite anything.
923 static int verify_clean_submodule(struct cache_entry *ce, const char *action,
924 struct unpack_trees_options *o)
926 return 0;
929 static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
930 struct unpack_trees_options *o)
933 * we are about to extract "ce->name"; we would not want to lose
934 * anything in the existing directory there.
936 int namelen;
937 int i;
938 struct dir_struct d;
939 char *pathbuf;
940 int cnt = 0;
941 unsigned char sha1[20];
943 if (S_ISGITLINK(ce->ce_mode) &&
944 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
945 /* If we are not going to update the submodule, then
946 * we don't care.
948 if (!hashcmp(sha1, ce->sha1))
949 return 0;
950 return verify_clean_submodule(ce, action, o);
954 * First let's make sure we do not have a local modification
955 * in that directory.
957 namelen = strlen(ce->name);
958 for (i = locate_in_src_index(ce, o);
959 i < o->src_index->cache_nr;
960 i++) {
961 struct cache_entry *ce2 = o->src_index->cache[i];
962 int len = ce_namelen(ce2);
963 if (len < namelen ||
964 strncmp(ce->name, ce2->name, namelen) ||
965 ce2->name[namelen] != '/')
966 break;
968 * ce2->name is an entry in the subdirectory to be
969 * removed.
971 if (!ce_stage(ce2)) {
972 if (verify_uptodate(ce2, o))
973 return -1;
974 add_entry(o, ce2, CE_REMOVE, 0);
975 mark_ce_used(ce2, o);
977 cnt++;
981 * Then we need to make sure that we do not lose a locally
982 * present file that is not ignored.
984 pathbuf = xmalloc(namelen + 2);
985 memcpy(pathbuf, ce->name, namelen);
986 strcpy(pathbuf+namelen, "/");
988 memset(&d, 0, sizeof(d));
989 if (o->dir)
990 d.exclude_per_dir = o->dir->exclude_per_dir;
991 i = read_directory(&d, pathbuf, namelen+1, NULL);
992 if (i)
993 return o->gently ? -1 :
994 error(ERRORMSG(o, not_uptodate_dir), ce->name);
995 free(pathbuf);
996 return cnt;
1000 * This gets called when there was no index entry for the tree entry 'dst',
1001 * but we found a file in the working tree that 'lstat()' said was fine,
1002 * and we're on a case-insensitive filesystem.
1004 * See if we can find a case-insensitive match in the index that also
1005 * matches the stat information, and assume it's that other file!
1007 static int icase_exists(struct unpack_trees_options *o, struct cache_entry *dst, struct stat *st)
1009 struct cache_entry *src;
1011 src = index_name_exists(o->src_index, dst->name, ce_namelen(dst), 1);
1012 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1016 * We do not want to remove or overwrite a working tree file that
1017 * is not tracked, unless it is ignored.
1019 static int verify_absent_1(struct cache_entry *ce, const char *action,
1020 struct unpack_trees_options *o,
1021 const char *error_msg)
1023 struct stat st;
1025 if (o->index_only || o->reset || !o->update)
1026 return 0;
1028 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
1029 return 0;
1031 if (!lstat(ce->name, &st)) {
1032 int dtype = ce_to_dtype(ce);
1033 struct cache_entry *result;
1036 * It may be that the 'lstat()' succeeded even though
1037 * target 'ce' was absent, because there is an old
1038 * entry that is different only in case..
1040 * Ignore that lstat() if it matches.
1042 if (ignore_case && icase_exists(o, ce, &st))
1043 return 0;
1045 if (o->dir && excluded(o->dir, ce->name, &dtype))
1047 * ce->name is explicitly excluded, so it is Ok to
1048 * overwrite it.
1050 return 0;
1051 if (S_ISDIR(st.st_mode)) {
1053 * We are checking out path "foo" and
1054 * found "foo/." in the working tree.
1055 * This is tricky -- if we have modified
1056 * files that are in "foo/" we would lose
1057 * them.
1059 if (verify_clean_subdirectory(ce, action, o) < 0)
1060 return -1;
1061 return 0;
1065 * The previous round may already have decided to
1066 * delete this path, which is in a subdirectory that
1067 * is being replaced with a blob.
1069 result = index_name_exists(&o->result, ce->name, ce_namelen(ce), 0);
1070 if (result) {
1071 if (result->ce_flags & CE_REMOVE)
1072 return 0;
1075 return o->gently ? -1 :
1076 error(ERRORMSG(o, would_lose_untracked), ce->name, action);
1078 return 0;
1080 static int verify_absent(struct cache_entry *ce, const char *action,
1081 struct unpack_trees_options *o)
1083 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
1084 return 0;
1085 return verify_absent_1(ce, action, o, ERRORMSG(o, would_lose_untracked));
1088 static int verify_absent_sparse(struct cache_entry *ce, const char *action,
1089 struct unpack_trees_options *o)
1091 return verify_absent_1(ce, action, o, ERRORMSG(o, would_lose_orphaned));
1094 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
1095 struct unpack_trees_options *o)
1097 int update = CE_UPDATE;
1099 if (!old) {
1100 if (verify_absent(merge, "overwritten", o))
1101 return -1;
1102 invalidate_ce_path(merge, o);
1103 } else if (!(old->ce_flags & CE_CONFLICTED)) {
1105 * See if we can re-use the old CE directly?
1106 * That way we get the uptodate stat info.
1108 * This also removes the UPDATE flag on a match; otherwise
1109 * we will end up overwriting local changes in the work tree.
1111 if (same(old, merge)) {
1112 copy_cache_entry(merge, old);
1113 update = 0;
1114 } else {
1115 if (verify_uptodate(old, o))
1116 return -1;
1117 if (ce_skip_worktree(old))
1118 update |= CE_SKIP_WORKTREE;
1119 invalidate_ce_path(old, o);
1121 } else {
1123 * Previously unmerged entry left as an existence
1124 * marker by read_index_unmerged();
1126 invalidate_ce_path(old, o);
1129 add_entry(o, merge, update, CE_STAGEMASK);
1130 return 1;
1133 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1134 struct unpack_trees_options *o)
1136 /* Did it exist in the index? */
1137 if (!old) {
1138 if (verify_absent(ce, "removed", o))
1139 return -1;
1140 return 0;
1142 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
1143 return -1;
1144 add_entry(o, ce, CE_REMOVE, 0);
1145 invalidate_ce_path(ce, o);
1146 return 1;
1149 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
1151 add_entry(o, ce, 0, 0);
1152 return 1;
1155 #if DBRT_DEBUG
1156 static void show_stage_entry(FILE *o,
1157 const char *label, const struct cache_entry *ce)
1159 if (!ce)
1160 fprintf(o, "%s (missing)\n", label);
1161 else
1162 fprintf(o, "%s%06o %s %d\t%s\n",
1163 label,
1164 ce->ce_mode,
1165 sha1_to_hex(ce->sha1),
1166 ce_stage(ce),
1167 ce->name);
1169 #endif
1171 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
1173 struct cache_entry *index;
1174 struct cache_entry *head;
1175 struct cache_entry *remote = stages[o->head_idx + 1];
1176 int count;
1177 int head_match = 0;
1178 int remote_match = 0;
1180 int df_conflict_head = 0;
1181 int df_conflict_remote = 0;
1183 int any_anc_missing = 0;
1184 int no_anc_exists = 1;
1185 int i;
1187 for (i = 1; i < o->head_idx; i++) {
1188 if (!stages[i] || stages[i] == o->df_conflict_entry)
1189 any_anc_missing = 1;
1190 else
1191 no_anc_exists = 0;
1194 index = stages[0];
1195 head = stages[o->head_idx];
1197 if (head == o->df_conflict_entry) {
1198 df_conflict_head = 1;
1199 head = NULL;
1202 if (remote == o->df_conflict_entry) {
1203 df_conflict_remote = 1;
1204 remote = NULL;
1208 * First, if there's a #16 situation, note that to prevent #13
1209 * and #14.
1211 if (!same(remote, head)) {
1212 for (i = 1; i < o->head_idx; i++) {
1213 if (same(stages[i], head)) {
1214 head_match = i;
1216 if (same(stages[i], remote)) {
1217 remote_match = i;
1223 * We start with cases where the index is allowed to match
1224 * something other than the head: #14(ALT) and #2ALT, where it
1225 * is permitted to match the result instead.
1227 /* #14, #14ALT, #2ALT */
1228 if (remote && !df_conflict_head && head_match && !remote_match) {
1229 if (index && !same(index, remote) && !same(index, head))
1230 return o->gently ? -1 : reject_merge(index, o);
1231 return merged_entry(remote, index, o);
1234 * If we have an entry in the index cache, then we want to
1235 * make sure that it matches head.
1237 if (index && !same(index, head))
1238 return o->gently ? -1 : reject_merge(index, o);
1240 if (head) {
1241 /* #5ALT, #15 */
1242 if (same(head, remote))
1243 return merged_entry(head, index, o);
1244 /* #13, #3ALT */
1245 if (!df_conflict_remote && remote_match && !head_match)
1246 return merged_entry(head, index, o);
1249 /* #1 */
1250 if (!head && !remote && any_anc_missing)
1251 return 0;
1254 * Under the "aggressive" rule, we resolve mostly trivial
1255 * cases that we historically had git-merge-one-file resolve.
1257 if (o->aggressive) {
1258 int head_deleted = !head;
1259 int remote_deleted = !remote;
1260 struct cache_entry *ce = NULL;
1262 if (index)
1263 ce = index;
1264 else if (head)
1265 ce = head;
1266 else if (remote)
1267 ce = remote;
1268 else {
1269 for (i = 1; i < o->head_idx; i++) {
1270 if (stages[i] && stages[i] != o->df_conflict_entry) {
1271 ce = stages[i];
1272 break;
1278 * Deleted in both.
1279 * Deleted in one and unchanged in the other.
1281 if ((head_deleted && remote_deleted) ||
1282 (head_deleted && remote && remote_match) ||
1283 (remote_deleted && head && head_match)) {
1284 if (index)
1285 return deleted_entry(index, index, o);
1286 if (ce && !head_deleted) {
1287 if (verify_absent(ce, "removed", o))
1288 return -1;
1290 return 0;
1293 * Added in both, identically.
1295 if (no_anc_exists && head && remote && same(head, remote))
1296 return merged_entry(head, index, o);
1300 /* Below are "no merge" cases, which require that the index be
1301 * up-to-date to avoid the files getting overwritten with
1302 * conflict resolution files.
1304 if (index) {
1305 if (verify_uptodate(index, o))
1306 return -1;
1309 o->nontrivial_merge = 1;
1311 /* #2, #3, #4, #6, #7, #9, #10, #11. */
1312 count = 0;
1313 if (!head_match || !remote_match) {
1314 for (i = 1; i < o->head_idx; i++) {
1315 if (stages[i] && stages[i] != o->df_conflict_entry) {
1316 keep_entry(stages[i], o);
1317 count++;
1318 break;
1322 #if DBRT_DEBUG
1323 else {
1324 fprintf(stderr, "read-tree: warning #16 detected\n");
1325 show_stage_entry(stderr, "head ", stages[head_match]);
1326 show_stage_entry(stderr, "remote ", stages[remote_match]);
1328 #endif
1329 if (head) { count += keep_entry(head, o); }
1330 if (remote) { count += keep_entry(remote, o); }
1331 return count;
1335 * Two-way merge.
1337 * The rule is to "carry forward" what is in the index without losing
1338 * information across a "fast-forward", favoring a successful merge
1339 * over a merge failure when it makes sense. For details of the
1340 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1343 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1345 struct cache_entry *current = src[0];
1346 struct cache_entry *oldtree = src[1];
1347 struct cache_entry *newtree = src[2];
1349 if (o->merge_size != 2)
1350 return error("Cannot do a twoway merge of %d trees",
1351 o->merge_size);
1353 if (oldtree == o->df_conflict_entry)
1354 oldtree = NULL;
1355 if (newtree == o->df_conflict_entry)
1356 newtree = NULL;
1358 if (current) {
1359 if ((!oldtree && !newtree) || /* 4 and 5 */
1360 (!oldtree && newtree &&
1361 same(current, newtree)) || /* 6 and 7 */
1362 (oldtree && newtree &&
1363 same(oldtree, newtree)) || /* 14 and 15 */
1364 (oldtree && newtree &&
1365 !same(oldtree, newtree) && /* 18 and 19 */
1366 same(current, newtree))) {
1367 return keep_entry(current, o);
1369 else if (oldtree && !newtree && same(current, oldtree)) {
1370 /* 10 or 11 */
1371 return deleted_entry(oldtree, current, o);
1373 else if (oldtree && newtree &&
1374 same(current, oldtree) && !same(current, newtree)) {
1375 /* 20 or 21 */
1376 return merged_entry(newtree, current, o);
1378 else {
1379 /* all other failures */
1380 if (oldtree)
1381 return o->gently ? -1 : reject_merge(oldtree, o);
1382 if (current)
1383 return o->gently ? -1 : reject_merge(current, o);
1384 if (newtree)
1385 return o->gently ? -1 : reject_merge(newtree, o);
1386 return -1;
1389 else if (newtree) {
1390 if (oldtree && !o->initial_checkout) {
1392 * deletion of the path was staged;
1394 if (same(oldtree, newtree))
1395 return 1;
1396 return reject_merge(oldtree, o);
1398 return merged_entry(newtree, current, o);
1400 return deleted_entry(oldtree, current, o);
1404 * Bind merge.
1406 * Keep the index entries at stage0, collapse stage1 but make sure
1407 * stage0 does not have anything there.
1409 int bind_merge(struct cache_entry **src,
1410 struct unpack_trees_options *o)
1412 struct cache_entry *old = src[0];
1413 struct cache_entry *a = src[1];
1415 if (o->merge_size != 1)
1416 return error("Cannot do a bind merge of %d trees\n",
1417 o->merge_size);
1418 if (a && old)
1419 return o->gently ? -1 :
1420 error(ERRORMSG(o, bind_overlap), a->name, old->name);
1421 if (!a)
1422 return keep_entry(old, o);
1423 else
1424 return merged_entry(a, NULL, o);
1428 * One-way merge.
1430 * The rule is:
1431 * - take the stat information from stage0, take the data from stage1
1433 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1435 struct cache_entry *old = src[0];
1436 struct cache_entry *a = src[1];
1438 if (o->merge_size != 1)
1439 return error("Cannot do a oneway merge of %d trees",
1440 o->merge_size);
1442 if (!a || a == o->df_conflict_entry)
1443 return deleted_entry(old, old, o);
1445 if (old && same(old, a)) {
1446 int update = 0;
1447 if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
1448 struct stat st;
1449 if (lstat(old->name, &st) ||
1450 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
1451 update |= CE_UPDATE;
1453 add_entry(o, old, update, 0);
1454 return 0;
1456 return merged_entry(a, old, o);