unpack_trees: group error messages by type
[git/git.git] / unpack-trees.c
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"
11
12 /*
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" and "git merge" replaces
17 * them using set_porcelain_error_msgs(), for example.
18 */
19 const char *unpack_plumbing_errors[NB_UNPACK_TREES_ERROR_TYPES] = {
20 /* ERROR_WOULD_OVERWRITE */
21 "Entry '%s' would be overwritten by merge. Cannot merge.",
22
23 /* ERROR_NOT_UPTODATE_FILE */
24 "Entry '%s' not uptodate. Cannot merge.",
25
26 /* ERROR_NOT_UPTODATE_DIR */
27 "Updating '%s' would lose untracked files in it",
28
29 /* ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN */
30 "Untracked working tree file '%s' would be overwritten by merge.",
31
32 /* ERROR_WOULD_LOSE_UNTRACKED_REMOVED */
33 "Untracked working tree file '%s' would be removed by merge.",
34
35 /* ERROR_BIND_OVERLAP */
36 "Entry '%s' overlaps with '%s'. Cannot bind.",
37
38 /* ERROR_SPARSE_NOT_UPTODATE_FILE */
39 "Entry '%s' not uptodate. Cannot update sparse checkout.",
40
41 /* ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN */
42 "Working tree file '%s' would be overwritten by sparse checkout update.",
43
44 /* ERROR_WOULD_LOSE_ORPHANED_REMOVED */
45 "Working tree file '%s' would be removed by sparse checkout update.",
46 };
47
48 #define ERRORMSG(o,type) \
49 ( ((o) && (o)->msgs[(type)]) \
50 ? ((o)->msgs[(type)]) \
51 : (unpack_plumbing_errors[(type)]) )
52
53 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
54 unsigned int set, unsigned int clear)
55 {
56 unsigned int size = ce_size(ce);
57 struct cache_entry *new = xmalloc(size);
58
59 clear |= CE_HASHED | CE_UNHASHED;
60
61 memcpy(new, ce, size);
62 new->next = NULL;
63 new->ce_flags = (new->ce_flags & ~clear) | set;
64 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
65 }
66
67 /*
68 * add error messages on path <path>
69 * corresponding to the type <e> with the message <msg>
70 * indicating if it should be display in porcelain or not
71 */
72 static int add_rejected_path(struct unpack_trees_options *o,
73 enum unpack_trees_error_types e,
74 const char *path)
75 {
76 struct rejected_paths_list *newentry;
77 int porcelain = o && (o)->msgs[e];
78 /*
79 * simply display the given error message if in plumbing mode
80 */
81 if (!porcelain)
82 o->show_all_errors = 0;
83 if (!o->show_all_errors)
84 return error(ERRORMSG(o, e), path);
85
86 /*
87 * Otherwise, insert in a list for future display by
88 * display_error_msgs()
89 */
90 newentry = xmalloc(sizeof(struct rejected_paths_list));
91 newentry->path = (char *)path;
92 newentry->next = o->unpack_rejects[e];
93 o->unpack_rejects[e] = newentry;
94 return -1;
95 }
96
97 /*
98 * free all the structures allocated for the error <e>
99 */
100 static void free_rejected_paths(struct unpack_trees_options *o,
101 enum unpack_trees_error_types e)
102 {
103 while (o->unpack_rejects[e]) {
104 struct rejected_paths_list *del = o->unpack_rejects[e];
105 o->unpack_rejects[e] = o->unpack_rejects[e]->next;
106 free(del);
107 }
108 free(o->unpack_rejects[e]);
109 }
110
111 /*
112 * display all the error messages stored in a nice way
113 */
114 static void display_error_msgs(struct unpack_trees_options *o)
115 {
116 int e;
117 int something_displayed = 0;
118 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
119 if (o->unpack_rejects[e]) {
120 struct rejected_paths_list *rp;
121 struct strbuf path = STRBUF_INIT;
122 something_displayed = 1;
123 for (rp = o->unpack_rejects[e]; rp; rp = rp->next)
124 strbuf_addf(&path, "\t%s\n", rp->path);
125 error(ERRORMSG(o, e), path.buf);
126 strbuf_release(&path);
127 free_rejected_paths(o, e);
128 }
129 }
130 if (something_displayed)
131 printf("Aborting\n");
132 }
133
134 /*
135 * Unlink the last component and schedule the leading directories for
136 * removal, such that empty directories get removed.
137 */
138 static void unlink_entry(struct cache_entry *ce)
139 {
140 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
141 return;
142 if (remove_or_warn(ce->ce_mode, ce->name))
143 return;
144 schedule_dir_for_removal(ce->name, ce_namelen(ce));
145 }
146
147 static struct checkout state;
148 static int check_updates(struct unpack_trees_options *o)
149 {
150 unsigned cnt = 0, total = 0;
151 struct progress *progress = NULL;
152 struct index_state *index = &o->result;
153 int i;
154 int errs = 0;
155
156 if (o->update && o->verbose_update) {
157 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
158 struct cache_entry *ce = index->cache[cnt];
159 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE | CE_WT_REMOVE))
160 total++;
161 }
162
163 progress = start_progress_delay("Checking out files",
164 total, 50, 1);
165 cnt = 0;
166 }
167
168 if (o->update)
169 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
170 for (i = 0; i < index->cache_nr; i++) {
171 struct cache_entry *ce = index->cache[i];
172
173 if (ce->ce_flags & CE_WT_REMOVE) {
174 display_progress(progress, ++cnt);
175 if (o->update)
176 unlink_entry(ce);
177 continue;
178 }
179
180 if (ce->ce_flags & CE_REMOVE) {
181 display_progress(progress, ++cnt);
182 if (o->update)
183 unlink_entry(ce);
184 }
185 }
186 remove_marked_cache_entries(&o->result);
187 remove_scheduled_dirs();
188
189 for (i = 0; i < index->cache_nr; i++) {
190 struct cache_entry *ce = index->cache[i];
191
192 if (ce->ce_flags & CE_UPDATE) {
193 display_progress(progress, ++cnt);
194 ce->ce_flags &= ~CE_UPDATE;
195 if (o->update) {
196 errs |= checkout_entry(ce, &state, NULL);
197 }
198 }
199 }
200 stop_progress(&progress);
201 if (o->update)
202 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
203 return errs != 0;
204 }
205
206 static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
207 static int verify_absent_sparse(struct cache_entry *ce, enum unpack_trees_error_types, struct unpack_trees_options *o);
208
209 static int will_have_skip_worktree(const struct cache_entry *ce, struct unpack_trees_options *o)
210 {
211 const char *basename;
212
213 if (ce_stage(ce))
214 return 0;
215
216 basename = strrchr(ce->name, '/');
217 basename = basename ? basename+1 : ce->name;
218 return excluded_from_list(ce->name, ce_namelen(ce), basename, NULL, o->el) <= 0;
219 }
220
221 static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
222 {
223 int was_skip_worktree = ce_skip_worktree(ce);
224
225 if (will_have_skip_worktree(ce, o))
226 ce->ce_flags |= CE_SKIP_WORKTREE;
227 else
228 ce->ce_flags &= ~CE_SKIP_WORKTREE;
229
230 /*
231 * We only care about files getting into the checkout area
232 * If merge strategies want to remove some, go ahead, this
233 * flag will be removed eventually in unpack_trees() if it's
234 * outside checkout area.
235 */
236 if (ce->ce_flags & CE_REMOVE)
237 return 0;
238
239 if (!was_skip_worktree && ce_skip_worktree(ce)) {
240 /*
241 * If CE_UPDATE is set, verify_uptodate() must be called already
242 * also stat info may have lost after merged_entry() so calling
243 * verify_uptodate() again may fail
244 */
245 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
246 return -1;
247 ce->ce_flags |= CE_WT_REMOVE;
248 }
249 if (was_skip_worktree && !ce_skip_worktree(ce)) {
250 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
251 return -1;
252 ce->ce_flags |= CE_UPDATE;
253 }
254 return 0;
255 }
256
257 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
258 {
259 int ret = o->fn(src, o);
260 if (ret > 0)
261 ret = 0;
262 return ret;
263 }
264
265 static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
266 {
267 ce->ce_flags |= CE_UNPACKED;
268
269 if (o->cache_bottom < o->src_index->cache_nr &&
270 o->src_index->cache[o->cache_bottom] == ce) {
271 int bottom = o->cache_bottom;
272 while (bottom < o->src_index->cache_nr &&
273 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
274 bottom++;
275 o->cache_bottom = bottom;
276 }
277 }
278
279 static void mark_all_ce_unused(struct index_state *index)
280 {
281 int i;
282 for (i = 0; i < index->cache_nr; i++)
283 index->cache[i]->ce_flags &= ~CE_UNPACKED;
284 }
285
286 static int locate_in_src_index(struct cache_entry *ce,
287 struct unpack_trees_options *o)
288 {
289 struct index_state *index = o->src_index;
290 int len = ce_namelen(ce);
291 int pos = index_name_pos(index, ce->name, len);
292 if (pos < 0)
293 pos = -1 - pos;
294 return pos;
295 }
296
297 /*
298 * We call unpack_index_entry() with an unmerged cache entry
299 * only in diff-index, and it wants a single callback. Skip
300 * the other unmerged entry with the same name.
301 */
302 static void mark_ce_used_same_name(struct cache_entry *ce,
303 struct unpack_trees_options *o)
304 {
305 struct index_state *index = o->src_index;
306 int len = ce_namelen(ce);
307 int pos;
308
309 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
310 struct cache_entry *next = index->cache[pos];
311 if (len != ce_namelen(next) ||
312 memcmp(ce->name, next->name, len))
313 break;
314 mark_ce_used(next, o);
315 }
316 }
317
318 static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
319 {
320 const struct index_state *index = o->src_index;
321 int pos = o->cache_bottom;
322
323 while (pos < index->cache_nr) {
324 struct cache_entry *ce = index->cache[pos];
325 if (!(ce->ce_flags & CE_UNPACKED))
326 return ce;
327 pos++;
328 }
329 return NULL;
330 }
331
332 static void add_same_unmerged(struct cache_entry *ce,
333 struct unpack_trees_options *o)
334 {
335 struct index_state *index = o->src_index;
336 int len = ce_namelen(ce);
337 int pos = index_name_pos(index, ce->name, len);
338
339 if (0 <= pos)
340 die("programming error in a caller of mark_ce_used_same_name");
341 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
342 struct cache_entry *next = index->cache[pos];
343 if (len != ce_namelen(next) ||
344 memcmp(ce->name, next->name, len))
345 break;
346 add_entry(o, next, 0, 0);
347 mark_ce_used(next, o);
348 }
349 }
350
351 static int unpack_index_entry(struct cache_entry *ce,
352 struct unpack_trees_options *o)
353 {
354 struct cache_entry *src[5] = { NULL };
355 int ret;
356
357 src[0] = ce;
358
359 mark_ce_used(ce, o);
360 if (ce_stage(ce)) {
361 if (o->skip_unmerged) {
362 add_entry(o, ce, 0, 0);
363 return 0;
364 }
365 }
366 ret = call_unpack_fn(src, o);
367 if (ce_stage(ce))
368 mark_ce_used_same_name(ce, o);
369 return ret;
370 }
371
372 static int find_cache_pos(struct traverse_info *, const struct name_entry *);
373
374 static void restore_cache_bottom(struct traverse_info *info, int bottom)
375 {
376 struct unpack_trees_options *o = info->data;
377
378 if (o->diff_index_cached)
379 return;
380 o->cache_bottom = bottom;
381 }
382
383 static int switch_cache_bottom(struct traverse_info *info)
384 {
385 struct unpack_trees_options *o = info->data;
386 int ret, pos;
387
388 if (o->diff_index_cached)
389 return 0;
390 ret = o->cache_bottom;
391 pos = find_cache_pos(info->prev, &info->name);
392
393 if (pos < -1)
394 o->cache_bottom = -2 - pos;
395 else if (pos < 0)
396 o->cache_bottom = o->src_index->cache_nr;
397 return ret;
398 }
399
400 static int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
401 {
402 int i, ret, bottom;
403 struct tree_desc t[MAX_UNPACK_TREES];
404 struct traverse_info newinfo;
405 struct name_entry *p;
406
407 p = names;
408 while (!p->mode)
409 p++;
410
411 newinfo = *info;
412 newinfo.prev = info;
413 newinfo.name = *p;
414 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
415 newinfo.conflicts |= df_conflicts;
416
417 for (i = 0; i < n; i++, dirmask >>= 1) {
418 const unsigned char *sha1 = NULL;
419 if (dirmask & 1)
420 sha1 = names[i].sha1;
421 fill_tree_descriptor(t+i, sha1);
422 }
423
424 bottom = switch_cache_bottom(&newinfo);
425 ret = traverse_trees(n, t, &newinfo);
426 restore_cache_bottom(&newinfo, bottom);
427 return ret;
428 }
429
430 /*
431 * Compare the traverse-path to the cache entry without actually
432 * having to generate the textual representation of the traverse
433 * path.
434 *
435 * NOTE! This *only* compares up to the size of the traverse path
436 * itself - the caller needs to do the final check for the cache
437 * entry having more data at the end!
438 */
439 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
440 {
441 int len, pathlen, ce_len;
442 const char *ce_name;
443
444 if (info->prev) {
445 int cmp = do_compare_entry(ce, info->prev, &info->name);
446 if (cmp)
447 return cmp;
448 }
449 pathlen = info->pathlen;
450 ce_len = ce_namelen(ce);
451
452 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
453 if (ce_len < pathlen)
454 return -1;
455
456 ce_len -= pathlen;
457 ce_name = ce->name + pathlen;
458
459 len = tree_entry_len(n->path, n->sha1);
460 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
461 }
462
463 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
464 {
465 int cmp = do_compare_entry(ce, info, n);
466 if (cmp)
467 return cmp;
468
469 /*
470 * Even if the beginning compared identically, the ce should
471 * compare as bigger than a directory leading up to it!
472 */
473 return ce_namelen(ce) > traverse_path_len(info, n);
474 }
475
476 static int ce_in_traverse_path(const struct cache_entry *ce,
477 const struct traverse_info *info)
478 {
479 if (!info->prev)
480 return 1;
481 if (do_compare_entry(ce, info->prev, &info->name))
482 return 0;
483 /*
484 * If ce (blob) is the same name as the path (which is a tree
485 * we will be descending into), it won't be inside it.
486 */
487 return (info->pathlen < ce_namelen(ce));
488 }
489
490 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
491 {
492 int len = traverse_path_len(info, n);
493 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
494
495 ce->ce_mode = create_ce_mode(n->mode);
496 ce->ce_flags = create_ce_flags(len, stage);
497 hashcpy(ce->sha1, n->sha1);
498 make_traverse_path(ce->name, info, n);
499
500 return ce;
501 }
502
503 static int unpack_nondirectories(int n, unsigned long mask,
504 unsigned long dirmask,
505 struct cache_entry **src,
506 const struct name_entry *names,
507 const struct traverse_info *info)
508 {
509 int i;
510 struct unpack_trees_options *o = info->data;
511 unsigned long conflicts;
512
513 /* Do we have *only* directories? Nothing to do */
514 if (mask == dirmask && !src[0])
515 return 0;
516
517 conflicts = info->conflicts;
518 if (o->merge)
519 conflicts >>= 1;
520 conflicts |= dirmask;
521
522 /*
523 * Ok, we've filled in up to any potential index entry in src[0],
524 * now do the rest.
525 */
526 for (i = 0; i < n; i++) {
527 int stage;
528 unsigned int bit = 1ul << i;
529 if (conflicts & bit) {
530 src[i + o->merge] = o->df_conflict_entry;
531 continue;
532 }
533 if (!(mask & bit))
534 continue;
535 if (!o->merge)
536 stage = 0;
537 else if (i + 1 < o->head_idx)
538 stage = 1;
539 else if (i + 1 > o->head_idx)
540 stage = 3;
541 else
542 stage = 2;
543 src[i + o->merge] = create_ce_entry(info, names + i, stage);
544 }
545
546 if (o->merge)
547 return call_unpack_fn(src, o);
548
549 for (i = 0; i < n; i++)
550 if (src[i] && src[i] != o->df_conflict_entry)
551 add_entry(o, src[i], 0, 0);
552 return 0;
553 }
554
555 static int unpack_failed(struct unpack_trees_options *o, const char *message)
556 {
557 discard_index(&o->result);
558 if (!o->gently) {
559 if (message)
560 return error("%s", message);
561 return -1;
562 }
563 return -1;
564 }
565
566 /* NEEDSWORK: give this a better name and share with tree-walk.c */
567 static int name_compare(const char *a, int a_len,
568 const char *b, int b_len)
569 {
570 int len = (a_len < b_len) ? a_len : b_len;
571 int cmp = memcmp(a, b, len);
572 if (cmp)
573 return cmp;
574 return (a_len - b_len);
575 }
576
577 /*
578 * The tree traversal is looking at name p. If we have a matching entry,
579 * return it. If name p is a directory in the index, do not return
580 * anything, as we will want to match it when the traversal descends into
581 * the directory.
582 */
583 static int find_cache_pos(struct traverse_info *info,
584 const struct name_entry *p)
585 {
586 int pos;
587 struct unpack_trees_options *o = info->data;
588 struct index_state *index = o->src_index;
589 int pfxlen = info->pathlen;
590 int p_len = tree_entry_len(p->path, p->sha1);
591
592 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
593 struct cache_entry *ce = index->cache[pos];
594 const char *ce_name, *ce_slash;
595 int cmp, ce_len;
596
597 if (ce->ce_flags & CE_UNPACKED) {
598 /*
599 * cache_bottom entry is already unpacked, so
600 * we can never match it; don't check it
601 * again.
602 */
603 if (pos == o->cache_bottom)
604 ++o->cache_bottom;
605 continue;
606 }
607 if (!ce_in_traverse_path(ce, info))
608 continue;
609 ce_name = ce->name + pfxlen;
610 ce_slash = strchr(ce_name, '/');
611 if (ce_slash)
612 ce_len = ce_slash - ce_name;
613 else
614 ce_len = ce_namelen(ce) - pfxlen;
615 cmp = name_compare(p->path, p_len, ce_name, ce_len);
616 /*
617 * Exact match; if we have a directory we need to
618 * delay returning it.
619 */
620 if (!cmp)
621 return ce_slash ? -2 - pos : pos;
622 if (0 < cmp)
623 continue; /* keep looking */
624 /*
625 * ce_name sorts after p->path; could it be that we
626 * have files under p->path directory in the index?
627 * E.g. ce_name == "t-i", and p->path == "t"; we may
628 * have "t/a" in the index.
629 */
630 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
631 ce_name[p_len] < '/')
632 continue; /* keep looking */
633 break;
634 }
635 return -1;
636 }
637
638 static struct cache_entry *find_cache_entry(struct traverse_info *info,
639 const struct name_entry *p)
640 {
641 int pos = find_cache_pos(info, p);
642 struct unpack_trees_options *o = info->data;
643
644 if (0 <= pos)
645 return o->src_index->cache[pos];
646 else
647 return NULL;
648 }
649
650 static void debug_path(struct traverse_info *info)
651 {
652 if (info->prev) {
653 debug_path(info->prev);
654 if (*info->prev->name.path)
655 putchar('/');
656 }
657 printf("%s", info->name.path);
658 }
659
660 static void debug_name_entry(int i, struct name_entry *n)
661 {
662 printf("ent#%d %06o %s\n", i,
663 n->path ? n->mode : 0,
664 n->path ? n->path : "(missing)");
665 }
666
667 static void debug_unpack_callback(int n,
668 unsigned long mask,
669 unsigned long dirmask,
670 struct name_entry *names,
671 struct traverse_info *info)
672 {
673 int i;
674 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
675 mask, dirmask, n);
676 debug_path(info);
677 putchar('\n');
678 for (i = 0; i < n; i++)
679 debug_name_entry(i, names + i);
680 }
681
682 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
683 {
684 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
685 struct unpack_trees_options *o = info->data;
686 const struct name_entry *p = names;
687
688 /* Find first entry with a real name (we could use "mask" too) */
689 while (!p->mode)
690 p++;
691
692 if (o->debug_unpack)
693 debug_unpack_callback(n, mask, dirmask, names, info);
694
695 /* Are we supposed to look at the index too? */
696 if (o->merge) {
697 while (1) {
698 int cmp;
699 struct cache_entry *ce;
700
701 if (o->diff_index_cached)
702 ce = next_cache_entry(o);
703 else
704 ce = find_cache_entry(info, p);
705
706 if (!ce)
707 break;
708 cmp = compare_entry(ce, info, p);
709 if (cmp < 0) {
710 if (unpack_index_entry(ce, o) < 0)
711 return unpack_failed(o, NULL);
712 continue;
713 }
714 if (!cmp) {
715 if (ce_stage(ce)) {
716 /*
717 * If we skip unmerged index
718 * entries, we'll skip this
719 * entry *and* the tree
720 * entries associated with it!
721 */
722 if (o->skip_unmerged) {
723 add_same_unmerged(ce, o);
724 return mask;
725 }
726 }
727 src[0] = ce;
728 }
729 break;
730 }
731 }
732
733 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
734 return -1;
735
736 if (src[0]) {
737 if (ce_stage(src[0]))
738 mark_ce_used_same_name(src[0], o);
739 else
740 mark_ce_used(src[0], o);
741 }
742
743 /* Now handle any directories.. */
744 if (dirmask) {
745 unsigned long conflicts = mask & ~dirmask;
746 if (o->merge) {
747 conflicts <<= 1;
748 if (src[0])
749 conflicts |= 1;
750 }
751
752 /* special case: "diff-index --cached" looking at a tree */
753 if (o->diff_index_cached &&
754 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
755 int matches;
756 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
757 names, info);
758 /*
759 * Everything under the name matches; skip the
760 * entire hierarchy. diff_index_cached codepath
761 * special cases D/F conflicts in such a way that
762 * it does not do any look-ahead, so this is safe.
763 */
764 if (matches) {
765 o->cache_bottom += matches;
766 return mask;
767 }
768 }
769
770 if (traverse_trees_recursive(n, dirmask, conflicts,
771 names, info) < 0)
772 return -1;
773 return mask;
774 }
775
776 return mask;
777 }
778
779 /*
780 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
781 * resulting index, -2 on failure to reflect the changes to the work tree.
782 */
783 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
784 {
785 int i, ret;
786 static struct cache_entry *dfc;
787 struct exclude_list el;
788
789 if (len > MAX_UNPACK_TREES)
790 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
791 memset(&state, 0, sizeof(state));
792 state.base_dir = "";
793 state.force = 1;
794 state.quiet = 1;
795 state.refresh_cache = 1;
796
797 memset(&el, 0, sizeof(el));
798 if (!core_apply_sparse_checkout || !o->update)
799 o->skip_sparse_checkout = 1;
800 if (!o->skip_sparse_checkout) {
801 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
802 o->skip_sparse_checkout = 1;
803 else
804 o->el = &el;
805 }
806
807 memset(&o->result, 0, sizeof(o->result));
808 o->result.initialized = 1;
809 o->result.timestamp.sec = o->src_index->timestamp.sec;
810 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
811 o->merge_size = len;
812 mark_all_ce_unused(o->src_index);
813
814 if (!dfc)
815 dfc = xcalloc(1, cache_entry_size(0));
816 o->df_conflict_entry = dfc;
817
818 if (len) {
819 const char *prefix = o->prefix ? o->prefix : "";
820 struct traverse_info info;
821
822 setup_traverse_info(&info, prefix);
823 info.fn = unpack_callback;
824 info.data = o;
825 info.show_all_errors = o->show_all_errors;
826
827 if (o->prefix) {
828 /*
829 * Unpack existing index entries that sort before the
830 * prefix the tree is spliced into. Note that o->merge
831 * is always true in this case.
832 */
833 while (1) {
834 struct cache_entry *ce = next_cache_entry(o);
835 if (!ce)
836 break;
837 if (ce_in_traverse_path(ce, &info))
838 break;
839 if (unpack_index_entry(ce, o) < 0)
840 goto return_failed;
841 }
842 }
843
844 if (traverse_trees(len, t, &info) < 0)
845 goto return_failed;
846 }
847
848 /* Any left-over entries in the index? */
849 if (o->merge) {
850 while (1) {
851 struct cache_entry *ce = next_cache_entry(o);
852 if (!ce)
853 break;
854 if (unpack_index_entry(ce, o) < 0)
855 goto return_failed;
856 }
857 }
858 mark_all_ce_unused(o->src_index);
859
860 if (o->trivial_merges_only && o->nontrivial_merge) {
861 ret = unpack_failed(o, "Merge requires file-level merging");
862 goto done;
863 }
864
865 if (!o->skip_sparse_checkout) {
866 int empty_worktree = 1;
867 for (i = 0;i < o->result.cache_nr;i++) {
868 struct cache_entry *ce = o->result.cache[i];
869
870 if (apply_sparse_checkout(ce, o)) {
871 ret = -1;
872 goto done;
873 }
874 /*
875 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
876 * area as a result of ce_skip_worktree() shortcuts in
877 * verify_absent() and verify_uptodate(). Clear them.
878 */
879 if (ce_skip_worktree(ce))
880 ce->ce_flags &= ~(CE_UPDATE | CE_REMOVE);
881 else
882 empty_worktree = 0;
883
884 }
885 if (o->result.cache_nr && empty_worktree) {
886 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
887 goto done;
888 }
889 }
890
891 o->src_index = NULL;
892 ret = check_updates(o) ? (-2) : 0;
893 if (o->dst_index)
894 *o->dst_index = o->result;
895
896 done:
897 for (i = 0;i < el.nr;i++)
898 free(el.excludes[i]);
899 if (el.excludes)
900 free(el.excludes);
901
902 return ret;
903
904 return_failed:
905 if (o->show_all_errors)
906 display_error_msgs(o);
907 mark_all_ce_unused(o->src_index);
908 ret = unpack_failed(o, NULL);
909 goto done;
910 }
911
912 /* Here come the merge functions */
913
914 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
915 {
916 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
917 }
918
919 static int same(struct cache_entry *a, struct cache_entry *b)
920 {
921 if (!!a != !!b)
922 return 0;
923 if (!a && !b)
924 return 1;
925 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
926 return 0;
927 return a->ce_mode == b->ce_mode &&
928 !hashcmp(a->sha1, b->sha1);
929 }
930
931
932 /*
933 * When a CE gets turned into an unmerged entry, we
934 * want it to be up-to-date
935 */
936 static int verify_uptodate_1(struct cache_entry *ce,
937 struct unpack_trees_options *o,
938 enum unpack_trees_error_types error_type)
939 {
940 struct stat st;
941
942 if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
943 return 0;
944
945 if (!lstat(ce->name, &st)) {
946 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
947 if (!changed)
948 return 0;
949 /*
950 * NEEDSWORK: the current default policy is to allow
951 * submodule to be out of sync wrt the supermodule
952 * index. This needs to be tightened later for
953 * submodules that are marked to be automatically
954 * checked out.
955 */
956 if (S_ISGITLINK(ce->ce_mode))
957 return 0;
958 errno = 0;
959 }
960 if (errno == ENOENT)
961 return 0;
962 return o->gently ? -1 :
963 add_rejected_path(o, error_type, ce->name);
964 }
965
966 static int verify_uptodate(struct cache_entry *ce,
967 struct unpack_trees_options *o)
968 {
969 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
970 return 0;
971 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
972 }
973
974 static int verify_uptodate_sparse(struct cache_entry *ce,
975 struct unpack_trees_options *o)
976 {
977 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
978 }
979
980 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
981 {
982 if (ce)
983 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
984 }
985
986 /*
987 * Check that checking out ce->sha1 in subdir ce->name is not
988 * going to overwrite any working files.
989 *
990 * Currently, git does not checkout subprojects during a superproject
991 * checkout, so it is not going to overwrite anything.
992 */
993 static int verify_clean_submodule(struct cache_entry *ce,
994 enum unpack_trees_error_types error_type,
995 struct unpack_trees_options *o)
996 {
997 return 0;
998 }
999
1000 static int verify_clean_subdirectory(struct cache_entry *ce,
1001 enum unpack_trees_error_types error_type,
1002 struct unpack_trees_options *o)
1003 {
1004 /*
1005 * we are about to extract "ce->name"; we would not want to lose
1006 * anything in the existing directory there.
1007 */
1008 int namelen;
1009 int i;
1010 struct dir_struct d;
1011 char *pathbuf;
1012 int cnt = 0;
1013 unsigned char sha1[20];
1014
1015 if (S_ISGITLINK(ce->ce_mode) &&
1016 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1017 /* If we are not going to update the submodule, then
1018 * we don't care.
1019 */
1020 if (!hashcmp(sha1, ce->sha1))
1021 return 0;
1022 return verify_clean_submodule(ce, error_type, o);
1023 }
1024
1025 /*
1026 * First let's make sure we do not have a local modification
1027 * in that directory.
1028 */
1029 namelen = strlen(ce->name);
1030 for (i = locate_in_src_index(ce, o);
1031 i < o->src_index->cache_nr;
1032 i++) {
1033 struct cache_entry *ce2 = o->src_index->cache[i];
1034 int len = ce_namelen(ce2);
1035 if (len < namelen ||
1036 strncmp(ce->name, ce2->name, namelen) ||
1037 ce2->name[namelen] != '/')
1038 break;
1039 /*
1040 * ce2->name is an entry in the subdirectory to be
1041 * removed.
1042 */
1043 if (!ce_stage(ce2)) {
1044 if (verify_uptodate(ce2, o))
1045 return -1;
1046 add_entry(o, ce2, CE_REMOVE, 0);
1047 mark_ce_used(ce2, o);
1048 }
1049 cnt++;
1050 }
1051
1052 /*
1053 * Then we need to make sure that we do not lose a locally
1054 * present file that is not ignored.
1055 */
1056 pathbuf = xmalloc(namelen + 2);
1057 memcpy(pathbuf, ce->name, namelen);
1058 strcpy(pathbuf+namelen, "/");
1059
1060 memset(&d, 0, sizeof(d));
1061 if (o->dir)
1062 d.exclude_per_dir = o->dir->exclude_per_dir;
1063 i = read_directory(&d, pathbuf, namelen+1, NULL);
1064 if (i)
1065 return o->gently ? -1 :
1066 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1067 free(pathbuf);
1068 return cnt;
1069 }
1070
1071 /*
1072 * This gets called when there was no index entry for the tree entry 'dst',
1073 * but we found a file in the working tree that 'lstat()' said was fine,
1074 * and we're on a case-insensitive filesystem.
1075 *
1076 * See if we can find a case-insensitive match in the index that also
1077 * matches the stat information, and assume it's that other file!
1078 */
1079 static int icase_exists(struct unpack_trees_options *o, struct cache_entry *dst, struct stat *st)
1080 {
1081 struct cache_entry *src;
1082
1083 src = index_name_exists(o->src_index, dst->name, ce_namelen(dst), 1);
1084 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1085 }
1086
1087 /*
1088 * We do not want to remove or overwrite a working tree file that
1089 * is not tracked, unless it is ignored.
1090 */
1091 static int verify_absent_1(struct cache_entry *ce,
1092 enum unpack_trees_error_types error_type,
1093 struct unpack_trees_options *o)
1094 {
1095 struct stat st;
1096
1097 if (o->index_only || o->reset || !o->update)
1098 return 0;
1099
1100 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
1101 return 0;
1102
1103 if (!lstat(ce->name, &st)) {
1104 int dtype = ce_to_dtype(ce);
1105 struct cache_entry *result;
1106
1107 /*
1108 * It may be that the 'lstat()' succeeded even though
1109 * target 'ce' was absent, because there is an old
1110 * entry that is different only in case..
1111 *
1112 * Ignore that lstat() if it matches.
1113 */
1114 if (ignore_case && icase_exists(o, ce, &st))
1115 return 0;
1116
1117 if (o->dir && excluded(o->dir, ce->name, &dtype))
1118 /*
1119 * ce->name is explicitly excluded, so it is Ok to
1120 * overwrite it.
1121 */
1122 return 0;
1123 if (S_ISDIR(st.st_mode)) {
1124 /*
1125 * We are checking out path "foo" and
1126 * found "foo/." in the working tree.
1127 * This is tricky -- if we have modified
1128 * files that are in "foo/" we would lose
1129 * them.
1130 */
1131 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1132 return -1;
1133 return 0;
1134 }
1135
1136 /*
1137 * The previous round may already have decided to
1138 * delete this path, which is in a subdirectory that
1139 * is being replaced with a blob.
1140 */
1141 result = index_name_exists(&o->result, ce->name, ce_namelen(ce), 0);
1142 if (result) {
1143 if (result->ce_flags & CE_REMOVE)
1144 return 0;
1145 }
1146
1147 return o->gently ? -1 :
1148 add_rejected_path(o, error_type, ce->name);
1149 }
1150 return 0;
1151 }
1152 static int verify_absent(struct cache_entry *ce,
1153 enum unpack_trees_error_types error_type,
1154 struct unpack_trees_options *o)
1155 {
1156 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
1157 return 0;
1158 return verify_absent_1(ce, error_type, o);
1159 }
1160
1161 static int verify_absent_sparse(struct cache_entry *ce,
1162 enum unpack_trees_error_types error_type,
1163 struct unpack_trees_options *o)
1164 {
1165 enum unpack_trees_error_types orphaned_error = error_type;
1166 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1167 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1168
1169 return verify_absent_1(ce, orphaned_error, o);
1170 }
1171
1172 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
1173 struct unpack_trees_options *o)
1174 {
1175 int update = CE_UPDATE;
1176
1177 if (!old) {
1178 if (verify_absent(merge, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
1179 return -1;
1180 invalidate_ce_path(merge, o);
1181 } else if (!(old->ce_flags & CE_CONFLICTED)) {
1182 /*
1183 * See if we can re-use the old CE directly?
1184 * That way we get the uptodate stat info.
1185 *
1186 * This also removes the UPDATE flag on a match; otherwise
1187 * we will end up overwriting local changes in the work tree.
1188 */
1189 if (same(old, merge)) {
1190 copy_cache_entry(merge, old);
1191 update = 0;
1192 } else {
1193 if (verify_uptodate(old, o))
1194 return -1;
1195 if (ce_skip_worktree(old))
1196 update |= CE_SKIP_WORKTREE;
1197 invalidate_ce_path(old, o);
1198 }
1199 } else {
1200 /*
1201 * Previously unmerged entry left as an existence
1202 * marker by read_index_unmerged();
1203 */
1204 invalidate_ce_path(old, o);
1205 }
1206
1207 add_entry(o, merge, update, CE_STAGEMASK);
1208 return 1;
1209 }
1210
1211 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1212 struct unpack_trees_options *o)
1213 {
1214 /* Did it exist in the index? */
1215 if (!old) {
1216 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1217 return -1;
1218 return 0;
1219 }
1220 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
1221 return -1;
1222 add_entry(o, ce, CE_REMOVE, 0);
1223 invalidate_ce_path(ce, o);
1224 return 1;
1225 }
1226
1227 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
1228 {
1229 add_entry(o, ce, 0, 0);
1230 return 1;
1231 }
1232
1233 #if DBRT_DEBUG
1234 static void show_stage_entry(FILE *o,
1235 const char *label, const struct cache_entry *ce)
1236 {
1237 if (!ce)
1238 fprintf(o, "%s (missing)\n", label);
1239 else
1240 fprintf(o, "%s%06o %s %d\t%s\n",
1241 label,
1242 ce->ce_mode,
1243 sha1_to_hex(ce->sha1),
1244 ce_stage(ce),
1245 ce->name);
1246 }
1247 #endif
1248
1249 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
1250 {
1251 struct cache_entry *index;
1252 struct cache_entry *head;
1253 struct cache_entry *remote = stages[o->head_idx + 1];
1254 int count;
1255 int head_match = 0;
1256 int remote_match = 0;
1257
1258 int df_conflict_head = 0;
1259 int df_conflict_remote = 0;
1260
1261 int any_anc_missing = 0;
1262 int no_anc_exists = 1;
1263 int i;
1264
1265 for (i = 1; i < o->head_idx; i++) {
1266 if (!stages[i] || stages[i] == o->df_conflict_entry)
1267 any_anc_missing = 1;
1268 else
1269 no_anc_exists = 0;
1270 }
1271
1272 index = stages[0];
1273 head = stages[o->head_idx];
1274
1275 if (head == o->df_conflict_entry) {
1276 df_conflict_head = 1;
1277 head = NULL;
1278 }
1279
1280 if (remote == o->df_conflict_entry) {
1281 df_conflict_remote = 1;
1282 remote = NULL;
1283 }
1284
1285 /*
1286 * First, if there's a #16 situation, note that to prevent #13
1287 * and #14.
1288 */
1289 if (!same(remote, head)) {
1290 for (i = 1; i < o->head_idx; i++) {
1291 if (same(stages[i], head)) {
1292 head_match = i;
1293 }
1294 if (same(stages[i], remote)) {
1295 remote_match = i;
1296 }
1297 }
1298 }
1299
1300 /*
1301 * We start with cases where the index is allowed to match
1302 * something other than the head: #14(ALT) and #2ALT, where it
1303 * is permitted to match the result instead.
1304 */
1305 /* #14, #14ALT, #2ALT */
1306 if (remote && !df_conflict_head && head_match && !remote_match) {
1307 if (index && !same(index, remote) && !same(index, head))
1308 return o->gently ? -1 : reject_merge(index, o);
1309 return merged_entry(remote, index, o);
1310 }
1311 /*
1312 * If we have an entry in the index cache, then we want to
1313 * make sure that it matches head.
1314 */
1315 if (index && !same(index, head))
1316 return o->gently ? -1 : reject_merge(index, o);
1317
1318 if (head) {
1319 /* #5ALT, #15 */
1320 if (same(head, remote))
1321 return merged_entry(head, index, o);
1322 /* #13, #3ALT */
1323 if (!df_conflict_remote && remote_match && !head_match)
1324 return merged_entry(head, index, o);
1325 }
1326
1327 /* #1 */
1328 if (!head && !remote && any_anc_missing)
1329 return 0;
1330
1331 /*
1332 * Under the "aggressive" rule, we resolve mostly trivial
1333 * cases that we historically had git-merge-one-file resolve.
1334 */
1335 if (o->aggressive) {
1336 int head_deleted = !head;
1337 int remote_deleted = !remote;
1338 struct cache_entry *ce = NULL;
1339
1340 if (index)
1341 ce = index;
1342 else if (head)
1343 ce = head;
1344 else if (remote)
1345 ce = remote;
1346 else {
1347 for (i = 1; i < o->head_idx; i++) {
1348 if (stages[i] && stages[i] != o->df_conflict_entry) {
1349 ce = stages[i];
1350 break;
1351 }
1352 }
1353 }
1354
1355 /*
1356 * Deleted in both.
1357 * Deleted in one and unchanged in the other.
1358 */
1359 if ((head_deleted && remote_deleted) ||
1360 (head_deleted && remote && remote_match) ||
1361 (remote_deleted && head && head_match)) {
1362 if (index)
1363 return deleted_entry(index, index, o);
1364 if (ce && !head_deleted) {
1365 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1366 return -1;
1367 }
1368 return 0;
1369 }
1370 /*
1371 * Added in both, identically.
1372 */
1373 if (no_anc_exists && head && remote && same(head, remote))
1374 return merged_entry(head, index, o);
1375
1376 }
1377
1378 /* Below are "no merge" cases, which require that the index be
1379 * up-to-date to avoid the files getting overwritten with
1380 * conflict resolution files.
1381 */
1382 if (index) {
1383 if (verify_uptodate(index, o))
1384 return -1;
1385 }
1386
1387 o->nontrivial_merge = 1;
1388
1389 /* #2, #3, #4, #6, #7, #9, #10, #11. */
1390 count = 0;
1391 if (!head_match || !remote_match) {
1392 for (i = 1; i < o->head_idx; i++) {
1393 if (stages[i] && stages[i] != o->df_conflict_entry) {
1394 keep_entry(stages[i], o);
1395 count++;
1396 break;
1397 }
1398 }
1399 }
1400 #if DBRT_DEBUG
1401 else {
1402 fprintf(stderr, "read-tree: warning #16 detected\n");
1403 show_stage_entry(stderr, "head ", stages[head_match]);
1404 show_stage_entry(stderr, "remote ", stages[remote_match]);
1405 }
1406 #endif
1407 if (head) { count += keep_entry(head, o); }
1408 if (remote) { count += keep_entry(remote, o); }
1409 return count;
1410 }
1411
1412 /*
1413 * Two-way merge.
1414 *
1415 * The rule is to "carry forward" what is in the index without losing
1416 * information across a "fast-forward", favoring a successful merge
1417 * over a merge failure when it makes sense. For details of the
1418 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1419 *
1420 */
1421 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1422 {
1423 struct cache_entry *current = src[0];
1424 struct cache_entry *oldtree = src[1];
1425 struct cache_entry *newtree = src[2];
1426
1427 if (o->merge_size != 2)
1428 return error("Cannot do a twoway merge of %d trees",
1429 o->merge_size);
1430
1431 if (oldtree == o->df_conflict_entry)
1432 oldtree = NULL;
1433 if (newtree == o->df_conflict_entry)
1434 newtree = NULL;
1435
1436 if (current) {
1437 if ((!oldtree && !newtree) || /* 4 and 5 */
1438 (!oldtree && newtree &&
1439 same(current, newtree)) || /* 6 and 7 */
1440 (oldtree && newtree &&
1441 same(oldtree, newtree)) || /* 14 and 15 */
1442 (oldtree && newtree &&
1443 !same(oldtree, newtree) && /* 18 and 19 */
1444 same(current, newtree))) {
1445 return keep_entry(current, o);
1446 }
1447 else if (oldtree && !newtree && same(current, oldtree)) {
1448 /* 10 or 11 */
1449 return deleted_entry(oldtree, current, o);
1450 }
1451 else if (oldtree && newtree &&
1452 same(current, oldtree) && !same(current, newtree)) {
1453 /* 20 or 21 */
1454 return merged_entry(newtree, current, o);
1455 }
1456 else {
1457 /* all other failures */
1458 if (oldtree)
1459 return o->gently ? -1 : reject_merge(oldtree, o);
1460 if (current)
1461 return o->gently ? -1 : reject_merge(current, o);
1462 if (newtree)
1463 return o->gently ? -1 : reject_merge(newtree, o);
1464 return -1;
1465 }
1466 }
1467 else if (newtree) {
1468 if (oldtree && !o->initial_checkout) {
1469 /*
1470 * deletion of the path was staged;
1471 */
1472 if (same(oldtree, newtree))
1473 return 1;
1474 return reject_merge(oldtree, o);
1475 }
1476 return merged_entry(newtree, current, o);
1477 }
1478 return deleted_entry(oldtree, current, o);
1479 }
1480
1481 /*
1482 * Bind merge.
1483 *
1484 * Keep the index entries at stage0, collapse stage1 but make sure
1485 * stage0 does not have anything there.
1486 */
1487 int bind_merge(struct cache_entry **src,
1488 struct unpack_trees_options *o)
1489 {
1490 struct cache_entry *old = src[0];
1491 struct cache_entry *a = src[1];
1492
1493 if (o->merge_size != 1)
1494 return error("Cannot do a bind merge of %d trees\n",
1495 o->merge_size);
1496 if (a && old)
1497 return o->gently ? -1 :
1498 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
1499 if (!a)
1500 return keep_entry(old, o);
1501 else
1502 return merged_entry(a, NULL, o);
1503 }
1504
1505 /*
1506 * One-way merge.
1507 *
1508 * The rule is:
1509 * - take the stat information from stage0, take the data from stage1
1510 */
1511 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1512 {
1513 struct cache_entry *old = src[0];
1514 struct cache_entry *a = src[1];
1515
1516 if (o->merge_size != 1)
1517 return error("Cannot do a oneway merge of %d trees",
1518 o->merge_size);
1519
1520 if (!a || a == o->df_conflict_entry)
1521 return deleted_entry(old, old, o);
1522
1523 if (old && same(old, a)) {
1524 int update = 0;
1525 if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
1526 struct stat st;
1527 if (lstat(old->name, &st) ||
1528 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
1529 update |= CE_UPDATE;
1530 }
1531 add_entry(o, old, update, 0);
1532 return 0;
1533 }
1534 return merged_entry(a, old, o);
1535 }