2fecef8022ef51d6524fd9545d37f5a9454f0479
[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 setup_unpack_trees_porcelain(), for example.
18 */
19 static 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 void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
54 const char *cmd)
55 {
56 int i;
57 const char **msgs = opts->msgs;
58 const char *msg;
59 char *tmp;
60 const char *cmd2 = strcmp(cmd, "checkout") ? cmd : "switch branches";
61 if (advice_commit_before_merge)
62 msg = "Your local changes to the following files would be overwritten by %s:\n%%s"
63 "Please, commit your changes or stash them before you can %s.";
64 else
65 msg = "Your local changes to the following files would be overwritten by %s:\n%%s";
66 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen(cmd2) - 2);
67 sprintf(tmp, msg, cmd, cmd2);
68 msgs[ERROR_WOULD_OVERWRITE] = tmp;
69 msgs[ERROR_NOT_UPTODATE_FILE] = tmp;
70
71 msgs[ERROR_NOT_UPTODATE_DIR] =
72 "Updating the following directories would lose untracked files in it:\n%s";
73
74 if (advice_commit_before_merge)
75 msg = "The following untracked working tree files would be %s by %s:\n%%s"
76 "Please move or remove them before you can %s.";
77 else
78 msg = "The following untracked working tree files would be %s by %s:\n%%s";
79 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("removed") + strlen(cmd2) - 4);
80 sprintf(tmp, msg, "removed", cmd, cmd2);
81 msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] = tmp;
82 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("overwritten") + strlen(cmd2) - 4);
83 sprintf(tmp, msg, "overwritten", cmd, cmd2);
84 msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] = tmp;
85
86 /*
87 * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
88 * cannot easily display it as a list.
89 */
90 msgs[ERROR_BIND_OVERLAP] = "Entry '%s' overlaps with '%s'. Cannot bind.";
91
92 msgs[ERROR_SPARSE_NOT_UPTODATE_FILE] =
93 "Cannot update sparse checkout: the following entries are not up-to-date:\n%s";
94 msgs[ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN] =
95 "The following Working tree files would be overwritten by sparse checkout update:\n%s";
96 msgs[ERROR_WOULD_LOSE_ORPHANED_REMOVED] =
97 "The following Working tree files would be removed by sparse checkout update:\n%s";
98
99 opts->show_all_errors = 1;
100 /* rejected paths may not have a static buffer */
101 for (i = 0; i < ARRAY_SIZE(opts->unpack_rejects); i++)
102 opts->unpack_rejects[i].strdup_strings = 1;
103 }
104
105 static void do_add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
106 unsigned int set, unsigned int clear)
107 {
108 clear |= CE_HASHED | CE_UNHASHED;
109
110 if (set & CE_REMOVE)
111 set |= CE_WT_REMOVE;
112
113 ce->next = NULL;
114 ce->ce_flags = (ce->ce_flags & ~clear) | set;
115 add_index_entry(&o->result, ce,
116 ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
117 }
118
119 static struct cache_entry *dup_entry(const struct cache_entry *ce)
120 {
121 unsigned int size = ce_size(ce);
122 struct cache_entry *new = xmalloc(size);
123
124 memcpy(new, ce, size);
125 return new;
126 }
127
128 static void add_entry(struct unpack_trees_options *o,
129 const struct cache_entry *ce,
130 unsigned int set, unsigned int clear)
131 {
132 do_add_entry(o, dup_entry(ce), set, clear);
133 }
134
135 /*
136 * add error messages on path <path>
137 * corresponding to the type <e> with the message <msg>
138 * indicating if it should be display in porcelain or not
139 */
140 static int add_rejected_path(struct unpack_trees_options *o,
141 enum unpack_trees_error_types e,
142 const char *path)
143 {
144 if (!o->show_all_errors)
145 return error(ERRORMSG(o, e), path);
146
147 /*
148 * Otherwise, insert in a list for future display by
149 * display_error_msgs()
150 */
151 string_list_append(&o->unpack_rejects[e], path);
152 return -1;
153 }
154
155 /*
156 * display all the error messages stored in a nice way
157 */
158 static void display_error_msgs(struct unpack_trees_options *o)
159 {
160 int e, i;
161 int something_displayed = 0;
162 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
163 struct string_list *rejects = &o->unpack_rejects[e];
164 if (rejects->nr > 0) {
165 struct strbuf path = STRBUF_INIT;
166 something_displayed = 1;
167 for (i = 0; i < rejects->nr; i++)
168 strbuf_addf(&path, "\t%s\n", rejects->items[i].string);
169 error(ERRORMSG(o, e), path.buf);
170 strbuf_release(&path);
171 }
172 string_list_clear(rejects, 0);
173 }
174 if (something_displayed)
175 fprintf(stderr, "Aborting\n");
176 }
177
178 /*
179 * Unlink the last component and schedule the leading directories for
180 * removal, such that empty directories get removed.
181 */
182 static void unlink_entry(struct cache_entry *ce)
183 {
184 if (!check_leading_path(ce->name, ce_namelen(ce)))
185 return;
186 if (remove_or_warn(ce->ce_mode, ce->name))
187 return;
188 schedule_dir_for_removal(ce->name, ce_namelen(ce));
189 }
190
191 static struct checkout state;
192 static int check_updates(struct unpack_trees_options *o)
193 {
194 unsigned cnt = 0, total = 0;
195 struct progress *progress = NULL;
196 struct index_state *index = &o->result;
197 int i;
198 int errs = 0;
199
200 if (o->update && o->verbose_update) {
201 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
202 struct cache_entry *ce = index->cache[cnt];
203 if (ce->ce_flags & (CE_UPDATE | CE_WT_REMOVE))
204 total++;
205 }
206
207 progress = start_progress_delay("Checking out files",
208 total, 50, 1);
209 cnt = 0;
210 }
211
212 if (o->update)
213 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
214 for (i = 0; i < index->cache_nr; i++) {
215 struct cache_entry *ce = index->cache[i];
216
217 if (ce->ce_flags & CE_WT_REMOVE) {
218 display_progress(progress, ++cnt);
219 if (o->update && !o->dry_run)
220 unlink_entry(ce);
221 continue;
222 }
223 }
224 remove_marked_cache_entries(&o->result);
225 remove_scheduled_dirs();
226
227 for (i = 0; i < index->cache_nr; i++) {
228 struct cache_entry *ce = index->cache[i];
229
230 if (ce->ce_flags & CE_UPDATE) {
231 display_progress(progress, ++cnt);
232 ce->ce_flags &= ~CE_UPDATE;
233 if (o->update && !o->dry_run) {
234 errs |= checkout_entry(ce, &state, NULL);
235 }
236 }
237 }
238 stop_progress(&progress);
239 if (o->update)
240 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
241 return errs != 0;
242 }
243
244 static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
245 static int verify_absent_sparse(struct cache_entry *ce, enum unpack_trees_error_types, struct unpack_trees_options *o);
246
247 static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
248 {
249 int was_skip_worktree = ce_skip_worktree(ce);
250
251 if (ce->ce_flags & CE_NEW_SKIP_WORKTREE)
252 ce->ce_flags |= CE_SKIP_WORKTREE;
253 else
254 ce->ce_flags &= ~CE_SKIP_WORKTREE;
255
256 /*
257 * if (!was_skip_worktree && !ce_skip_worktree()) {
258 * This is perfectly normal. Move on;
259 * }
260 */
261
262 /*
263 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
264 * area as a result of ce_skip_worktree() shortcuts in
265 * verify_absent() and verify_uptodate().
266 * Make sure they don't modify worktree if they are already
267 * outside checkout area
268 */
269 if (was_skip_worktree && ce_skip_worktree(ce)) {
270 ce->ce_flags &= ~CE_UPDATE;
271
272 /*
273 * By default, when CE_REMOVE is on, CE_WT_REMOVE is also
274 * on to get that file removed from both index and worktree.
275 * If that file is already outside worktree area, don't
276 * bother remove it.
277 */
278 if (ce->ce_flags & CE_REMOVE)
279 ce->ce_flags &= ~CE_WT_REMOVE;
280 }
281
282 if (!was_skip_worktree && ce_skip_worktree(ce)) {
283 /*
284 * If CE_UPDATE is set, verify_uptodate() must be called already
285 * also stat info may have lost after merged_entry() so calling
286 * verify_uptodate() again may fail
287 */
288 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
289 return -1;
290 ce->ce_flags |= CE_WT_REMOVE;
291 }
292 if (was_skip_worktree && !ce_skip_worktree(ce)) {
293 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
294 return -1;
295 ce->ce_flags |= CE_UPDATE;
296 }
297 return 0;
298 }
299
300 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
301 {
302 int ret = o->fn(src, o);
303 if (ret > 0)
304 ret = 0;
305 return ret;
306 }
307
308 static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
309 {
310 ce->ce_flags |= CE_UNPACKED;
311
312 if (o->cache_bottom < o->src_index->cache_nr &&
313 o->src_index->cache[o->cache_bottom] == ce) {
314 int bottom = o->cache_bottom;
315 while (bottom < o->src_index->cache_nr &&
316 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
317 bottom++;
318 o->cache_bottom = bottom;
319 }
320 }
321
322 static void mark_all_ce_unused(struct index_state *index)
323 {
324 int i;
325 for (i = 0; i < index->cache_nr; i++)
326 index->cache[i]->ce_flags &= ~(CE_UNPACKED | CE_ADDED | CE_NEW_SKIP_WORKTREE);
327 }
328
329 static int locate_in_src_index(struct cache_entry *ce,
330 struct unpack_trees_options *o)
331 {
332 struct index_state *index = o->src_index;
333 int len = ce_namelen(ce);
334 int pos = index_name_pos(index, ce->name, len);
335 if (pos < 0)
336 pos = -1 - pos;
337 return pos;
338 }
339
340 /*
341 * We call unpack_index_entry() with an unmerged cache entry
342 * only in diff-index, and it wants a single callback. Skip
343 * the other unmerged entry with the same name.
344 */
345 static void mark_ce_used_same_name(struct cache_entry *ce,
346 struct unpack_trees_options *o)
347 {
348 struct index_state *index = o->src_index;
349 int len = ce_namelen(ce);
350 int pos;
351
352 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
353 struct cache_entry *next = index->cache[pos];
354 if (len != ce_namelen(next) ||
355 memcmp(ce->name, next->name, len))
356 break;
357 mark_ce_used(next, o);
358 }
359 }
360
361 static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
362 {
363 const struct index_state *index = o->src_index;
364 int pos = o->cache_bottom;
365
366 while (pos < index->cache_nr) {
367 struct cache_entry *ce = index->cache[pos];
368 if (!(ce->ce_flags & CE_UNPACKED))
369 return ce;
370 pos++;
371 }
372 return NULL;
373 }
374
375 static void add_same_unmerged(struct cache_entry *ce,
376 struct unpack_trees_options *o)
377 {
378 struct index_state *index = o->src_index;
379 int len = ce_namelen(ce);
380 int pos = index_name_pos(index, ce->name, len);
381
382 if (0 <= pos)
383 die("programming error in a caller of mark_ce_used_same_name");
384 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
385 struct cache_entry *next = index->cache[pos];
386 if (len != ce_namelen(next) ||
387 memcmp(ce->name, next->name, len))
388 break;
389 add_entry(o, next, 0, 0);
390 mark_ce_used(next, o);
391 }
392 }
393
394 static int unpack_index_entry(struct cache_entry *ce,
395 struct unpack_trees_options *o)
396 {
397 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
398 int ret;
399
400 src[0] = ce;
401
402 mark_ce_used(ce, o);
403 if (ce_stage(ce)) {
404 if (o->skip_unmerged) {
405 add_entry(o, ce, 0, 0);
406 return 0;
407 }
408 }
409 ret = call_unpack_fn(src, o);
410 if (ce_stage(ce))
411 mark_ce_used_same_name(ce, o);
412 return ret;
413 }
414
415 static int find_cache_pos(struct traverse_info *, const struct name_entry *);
416
417 static void restore_cache_bottom(struct traverse_info *info, int bottom)
418 {
419 struct unpack_trees_options *o = info->data;
420
421 if (o->diff_index_cached)
422 return;
423 o->cache_bottom = bottom;
424 }
425
426 static int switch_cache_bottom(struct traverse_info *info)
427 {
428 struct unpack_trees_options *o = info->data;
429 int ret, pos;
430
431 if (o->diff_index_cached)
432 return 0;
433 ret = o->cache_bottom;
434 pos = find_cache_pos(info->prev, &info->name);
435
436 if (pos < -1)
437 o->cache_bottom = -2 - pos;
438 else if (pos < 0)
439 o->cache_bottom = o->src_index->cache_nr;
440 return ret;
441 }
442
443 static int traverse_trees_recursive(int n, unsigned long dirmask,
444 unsigned long df_conflicts,
445 struct name_entry *names,
446 struct traverse_info *info)
447 {
448 int i, ret, bottom;
449 struct tree_desc t[MAX_UNPACK_TREES];
450 void *buf[MAX_UNPACK_TREES];
451 struct traverse_info newinfo;
452 struct name_entry *p;
453
454 p = names;
455 while (!p->mode)
456 p++;
457
458 newinfo = *info;
459 newinfo.prev = info;
460 newinfo.pathspec = info->pathspec;
461 newinfo.name = *p;
462 newinfo.pathlen += tree_entry_len(p) + 1;
463 newinfo.conflicts |= df_conflicts;
464
465 for (i = 0; i < n; i++, dirmask >>= 1) {
466 const unsigned char *sha1 = NULL;
467 if (dirmask & 1)
468 sha1 = names[i].sha1;
469 buf[i] = fill_tree_descriptor(t+i, sha1);
470 }
471
472 bottom = switch_cache_bottom(&newinfo);
473 ret = traverse_trees(n, t, &newinfo);
474 restore_cache_bottom(&newinfo, bottom);
475
476 for (i = 0; i < n; i++)
477 free(buf[i]);
478
479 return ret;
480 }
481
482 /*
483 * Compare the traverse-path to the cache entry without actually
484 * having to generate the textual representation of the traverse
485 * path.
486 *
487 * NOTE! This *only* compares up to the size of the traverse path
488 * itself - the caller needs to do the final check for the cache
489 * entry having more data at the end!
490 */
491 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
492 {
493 int len, pathlen, ce_len;
494 const char *ce_name;
495
496 if (info->prev) {
497 int cmp = do_compare_entry(ce, info->prev, &info->name);
498 if (cmp)
499 return cmp;
500 }
501 pathlen = info->pathlen;
502 ce_len = ce_namelen(ce);
503
504 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
505 if (ce_len < pathlen)
506 return -1;
507
508 ce_len -= pathlen;
509 ce_name = ce->name + pathlen;
510
511 len = tree_entry_len(n);
512 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
513 }
514
515 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
516 {
517 int cmp = do_compare_entry(ce, info, n);
518 if (cmp)
519 return cmp;
520
521 /*
522 * Even if the beginning compared identically, the ce should
523 * compare as bigger than a directory leading up to it!
524 */
525 return ce_namelen(ce) > traverse_path_len(info, n);
526 }
527
528 static int ce_in_traverse_path(const struct cache_entry *ce,
529 const struct traverse_info *info)
530 {
531 if (!info->prev)
532 return 1;
533 if (do_compare_entry(ce, info->prev, &info->name))
534 return 0;
535 /*
536 * If ce (blob) is the same name as the path (which is a tree
537 * we will be descending into), it won't be inside it.
538 */
539 return (info->pathlen < ce_namelen(ce));
540 }
541
542 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
543 {
544 int len = traverse_path_len(info, n);
545 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
546
547 ce->ce_mode = create_ce_mode(n->mode);
548 ce->ce_flags = create_ce_flags(stage);
549 ce->ce_namelen = len;
550 hashcpy(ce->sha1, n->sha1);
551 make_traverse_path(ce->name, info, n);
552
553 return ce;
554 }
555
556 static int unpack_nondirectories(int n, unsigned long mask,
557 unsigned long dirmask,
558 struct cache_entry **src,
559 const struct name_entry *names,
560 const struct traverse_info *info)
561 {
562 int i;
563 struct unpack_trees_options *o = info->data;
564 unsigned long conflicts;
565
566 /* Do we have *only* directories? Nothing to do */
567 if (mask == dirmask && !src[0])
568 return 0;
569
570 conflicts = info->conflicts;
571 if (o->merge)
572 conflicts >>= 1;
573 conflicts |= dirmask;
574
575 /*
576 * Ok, we've filled in up to any potential index entry in src[0],
577 * now do the rest.
578 */
579 for (i = 0; i < n; i++) {
580 int stage;
581 unsigned int bit = 1ul << i;
582 if (conflicts & bit) {
583 src[i + o->merge] = o->df_conflict_entry;
584 continue;
585 }
586 if (!(mask & bit))
587 continue;
588 if (!o->merge)
589 stage = 0;
590 else if (i + 1 < o->head_idx)
591 stage = 1;
592 else if (i + 1 > o->head_idx)
593 stage = 3;
594 else
595 stage = 2;
596 src[i + o->merge] = create_ce_entry(info, names + i, stage);
597 }
598
599 if (o->merge)
600 return call_unpack_fn(src, o);
601
602 for (i = 0; i < n; i++)
603 if (src[i] && src[i] != o->df_conflict_entry)
604 do_add_entry(o, src[i], 0, 0);
605 return 0;
606 }
607
608 static int unpack_failed(struct unpack_trees_options *o, const char *message)
609 {
610 discard_index(&o->result);
611 if (!o->gently && !o->exiting_early) {
612 if (message)
613 return error("%s", message);
614 return -1;
615 }
616 return -1;
617 }
618
619 /* NEEDSWORK: give this a better name and share with tree-walk.c */
620 static int name_compare(const char *a, int a_len,
621 const char *b, int b_len)
622 {
623 int len = (a_len < b_len) ? a_len : b_len;
624 int cmp = memcmp(a, b, len);
625 if (cmp)
626 return cmp;
627 return (a_len - b_len);
628 }
629
630 /*
631 * The tree traversal is looking at name p. If we have a matching entry,
632 * return it. If name p is a directory in the index, do not return
633 * anything, as we will want to match it when the traversal descends into
634 * the directory.
635 */
636 static int find_cache_pos(struct traverse_info *info,
637 const struct name_entry *p)
638 {
639 int pos;
640 struct unpack_trees_options *o = info->data;
641 struct index_state *index = o->src_index;
642 int pfxlen = info->pathlen;
643 int p_len = tree_entry_len(p);
644
645 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
646 struct cache_entry *ce = index->cache[pos];
647 const char *ce_name, *ce_slash;
648 int cmp, ce_len;
649
650 if (ce->ce_flags & CE_UNPACKED) {
651 /*
652 * cache_bottom entry is already unpacked, so
653 * we can never match it; don't check it
654 * again.
655 */
656 if (pos == o->cache_bottom)
657 ++o->cache_bottom;
658 continue;
659 }
660 if (!ce_in_traverse_path(ce, info))
661 continue;
662 ce_name = ce->name + pfxlen;
663 ce_slash = strchr(ce_name, '/');
664 if (ce_slash)
665 ce_len = ce_slash - ce_name;
666 else
667 ce_len = ce_namelen(ce) - pfxlen;
668 cmp = name_compare(p->path, p_len, ce_name, ce_len);
669 /*
670 * Exact match; if we have a directory we need to
671 * delay returning it.
672 */
673 if (!cmp)
674 return ce_slash ? -2 - pos : pos;
675 if (0 < cmp)
676 continue; /* keep looking */
677 /*
678 * ce_name sorts after p->path; could it be that we
679 * have files under p->path directory in the index?
680 * E.g. ce_name == "t-i", and p->path == "t"; we may
681 * have "t/a" in the index.
682 */
683 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
684 ce_name[p_len] < '/')
685 continue; /* keep looking */
686 break;
687 }
688 return -1;
689 }
690
691 static struct cache_entry *find_cache_entry(struct traverse_info *info,
692 const struct name_entry *p)
693 {
694 int pos = find_cache_pos(info, p);
695 struct unpack_trees_options *o = info->data;
696
697 if (0 <= pos)
698 return o->src_index->cache[pos];
699 else
700 return NULL;
701 }
702
703 static void debug_path(struct traverse_info *info)
704 {
705 if (info->prev) {
706 debug_path(info->prev);
707 if (*info->prev->name.path)
708 putchar('/');
709 }
710 printf("%s", info->name.path);
711 }
712
713 static void debug_name_entry(int i, struct name_entry *n)
714 {
715 printf("ent#%d %06o %s\n", i,
716 n->path ? n->mode : 0,
717 n->path ? n->path : "(missing)");
718 }
719
720 static void debug_unpack_callback(int n,
721 unsigned long mask,
722 unsigned long dirmask,
723 struct name_entry *names,
724 struct traverse_info *info)
725 {
726 int i;
727 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
728 mask, dirmask, n);
729 debug_path(info);
730 putchar('\n');
731 for (i = 0; i < n; i++)
732 debug_name_entry(i, names + i);
733 }
734
735 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
736 {
737 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
738 struct unpack_trees_options *o = info->data;
739 const struct name_entry *p = names;
740
741 /* Find first entry with a real name (we could use "mask" too) */
742 while (!p->mode)
743 p++;
744
745 if (o->debug_unpack)
746 debug_unpack_callback(n, mask, dirmask, names, info);
747
748 /* Are we supposed to look at the index too? */
749 if (o->merge) {
750 while (1) {
751 int cmp;
752 struct cache_entry *ce;
753
754 if (o->diff_index_cached)
755 ce = next_cache_entry(o);
756 else
757 ce = find_cache_entry(info, p);
758
759 if (!ce)
760 break;
761 cmp = compare_entry(ce, info, p);
762 if (cmp < 0) {
763 if (unpack_index_entry(ce, o) < 0)
764 return unpack_failed(o, NULL);
765 continue;
766 }
767 if (!cmp) {
768 if (ce_stage(ce)) {
769 /*
770 * If we skip unmerged index
771 * entries, we'll skip this
772 * entry *and* the tree
773 * entries associated with it!
774 */
775 if (o->skip_unmerged) {
776 add_same_unmerged(ce, o);
777 return mask;
778 }
779 }
780 src[0] = ce;
781 }
782 break;
783 }
784 }
785
786 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
787 return -1;
788
789 if (o->merge && src[0]) {
790 if (ce_stage(src[0]))
791 mark_ce_used_same_name(src[0], o);
792 else
793 mark_ce_used(src[0], o);
794 }
795
796 /* Now handle any directories.. */
797 if (dirmask) {
798 unsigned long conflicts = mask & ~dirmask;
799 if (o->merge) {
800 conflicts <<= 1;
801 if (src[0])
802 conflicts |= 1;
803 }
804
805 /* special case: "diff-index --cached" looking at a tree */
806 if (o->diff_index_cached &&
807 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
808 int matches;
809 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
810 names, info);
811 /*
812 * Everything under the name matches; skip the
813 * entire hierarchy. diff_index_cached codepath
814 * special cases D/F conflicts in such a way that
815 * it does not do any look-ahead, so this is safe.
816 */
817 if (matches) {
818 o->cache_bottom += matches;
819 return mask;
820 }
821 }
822
823 if (traverse_trees_recursive(n, dirmask, conflicts,
824 names, info) < 0)
825 return -1;
826 return mask;
827 }
828
829 return mask;
830 }
831
832 static int clear_ce_flags_1(struct cache_entry **cache, int nr,
833 char *prefix, int prefix_len,
834 int select_mask, int clear_mask,
835 struct exclude_list *el, int defval);
836
837 /* Whole directory matching */
838 static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
839 char *prefix, int prefix_len,
840 char *basename,
841 int select_mask, int clear_mask,
842 struct exclude_list *el, int defval)
843 {
844 struct cache_entry **cache_end;
845 int dtype = DT_DIR;
846 int ret = is_excluded_from_list(prefix, prefix_len,
847 basename, &dtype, el);
848
849 prefix[prefix_len++] = '/';
850
851 /* If undecided, use matching result of parent dir in defval */
852 if (ret < 0)
853 ret = defval;
854
855 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
856 struct cache_entry *ce = *cache_end;
857 if (strncmp(ce->name, prefix, prefix_len))
858 break;
859 }
860
861 /*
862 * TODO: check el, if there are no patterns that may conflict
863 * with ret (iow, we know in advance the incl/excl
864 * decision for the entire directory), clear flag here without
865 * calling clear_ce_flags_1(). That function will call
866 * the expensive is_excluded_from_list() on every entry.
867 */
868 return clear_ce_flags_1(cache, cache_end - cache,
869 prefix, prefix_len,
870 select_mask, clear_mask,
871 el, ret);
872 }
873
874 /*
875 * Traverse the index, find every entry that matches according to
876 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
877 * number of traversed entries.
878 *
879 * If select_mask is non-zero, only entries whose ce_flags has on of
880 * those bits enabled are traversed.
881 *
882 * cache : pointer to an index entry
883 * prefix_len : an offset to its path
884 *
885 * The current path ("prefix") including the trailing '/' is
886 * cache[0]->name[0..(prefix_len-1)]
887 * Top level path has prefix_len zero.
888 */
889 static int clear_ce_flags_1(struct cache_entry **cache, int nr,
890 char *prefix, int prefix_len,
891 int select_mask, int clear_mask,
892 struct exclude_list *el, int defval)
893 {
894 struct cache_entry **cache_end = cache + nr;
895
896 /*
897 * Process all entries that have the given prefix and meet
898 * select_mask condition
899 */
900 while(cache != cache_end) {
901 struct cache_entry *ce = *cache;
902 const char *name, *slash;
903 int len, dtype, ret;
904
905 if (select_mask && !(ce->ce_flags & select_mask)) {
906 cache++;
907 continue;
908 }
909
910 if (prefix_len && strncmp(ce->name, prefix, prefix_len))
911 break;
912
913 name = ce->name + prefix_len;
914 slash = strchr(name, '/');
915
916 /* If it's a directory, try whole directory match first */
917 if (slash) {
918 int processed;
919
920 len = slash - name;
921 memcpy(prefix + prefix_len, name, len);
922
923 /*
924 * terminate the string (no trailing slash),
925 * clear_c_f_dir needs it
926 */
927 prefix[prefix_len + len] = '\0';
928 processed = clear_ce_flags_dir(cache, cache_end - cache,
929 prefix, prefix_len + len,
930 prefix + prefix_len,
931 select_mask, clear_mask,
932 el, defval);
933
934 /* clear_c_f_dir eats a whole dir already? */
935 if (processed) {
936 cache += processed;
937 continue;
938 }
939
940 prefix[prefix_len + len++] = '/';
941 cache += clear_ce_flags_1(cache, cache_end - cache,
942 prefix, prefix_len + len,
943 select_mask, clear_mask, el, defval);
944 continue;
945 }
946
947 /* Non-directory */
948 dtype = ce_to_dtype(ce);
949 ret = is_excluded_from_list(ce->name, ce_namelen(ce),
950 name, &dtype, el);
951 if (ret < 0)
952 ret = defval;
953 if (ret > 0)
954 ce->ce_flags &= ~clear_mask;
955 cache++;
956 }
957 return nr - (cache_end - cache);
958 }
959
960 static int clear_ce_flags(struct cache_entry **cache, int nr,
961 int select_mask, int clear_mask,
962 struct exclude_list *el)
963 {
964 char prefix[PATH_MAX];
965 return clear_ce_flags_1(cache, nr,
966 prefix, 0,
967 select_mask, clear_mask,
968 el, 0);
969 }
970
971 /*
972 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
973 */
974 static void mark_new_skip_worktree(struct exclude_list *el,
975 struct index_state *the_index,
976 int select_flag, int skip_wt_flag)
977 {
978 int i;
979
980 /*
981 * 1. Pretend the narrowest worktree: only unmerged entries
982 * are checked out
983 */
984 for (i = 0; i < the_index->cache_nr; i++) {
985 struct cache_entry *ce = the_index->cache[i];
986
987 if (select_flag && !(ce->ce_flags & select_flag))
988 continue;
989
990 if (!ce_stage(ce))
991 ce->ce_flags |= skip_wt_flag;
992 else
993 ce->ce_flags &= ~skip_wt_flag;
994 }
995
996 /*
997 * 2. Widen worktree according to sparse-checkout file.
998 * Matched entries will have skip_wt_flag cleared (i.e. "in")
999 */
1000 clear_ce_flags(the_index->cache, the_index->cache_nr,
1001 select_flag, skip_wt_flag, el);
1002 }
1003
1004 static int verify_absent(struct cache_entry *, enum unpack_trees_error_types, struct unpack_trees_options *);
1005 /*
1006 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
1007 * resulting index, -2 on failure to reflect the changes to the work tree.
1008 *
1009 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
1010 */
1011 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
1012 {
1013 int i, ret;
1014 static struct cache_entry *dfc;
1015 struct exclude_list el;
1016
1017 if (len > MAX_UNPACK_TREES)
1018 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1019 memset(&state, 0, sizeof(state));
1020 state.base_dir = "";
1021 state.force = 1;
1022 state.quiet = 1;
1023 state.refresh_cache = 1;
1024
1025 memset(&el, 0, sizeof(el));
1026 if (!core_apply_sparse_checkout || !o->update)
1027 o->skip_sparse_checkout = 1;
1028 if (!o->skip_sparse_checkout) {
1029 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, &el, 0) < 0)
1030 o->skip_sparse_checkout = 1;
1031 else
1032 o->el = &el;
1033 }
1034
1035 memset(&o->result, 0, sizeof(o->result));
1036 o->result.initialized = 1;
1037 o->result.timestamp.sec = o->src_index->timestamp.sec;
1038 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1039 o->result.version = o->src_index->version;
1040 o->merge_size = len;
1041 mark_all_ce_unused(o->src_index);
1042
1043 /*
1044 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1045 */
1046 if (!o->skip_sparse_checkout)
1047 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1048
1049 if (!dfc)
1050 dfc = xcalloc(1, cache_entry_size(0));
1051 o->df_conflict_entry = dfc;
1052
1053 if (len) {
1054 const char *prefix = o->prefix ? o->prefix : "";
1055 struct traverse_info info;
1056
1057 setup_traverse_info(&info, prefix);
1058 info.fn = unpack_callback;
1059 info.data = o;
1060 info.show_all_errors = o->show_all_errors;
1061 info.pathspec = o->pathspec;
1062
1063 if (o->prefix) {
1064 /*
1065 * Unpack existing index entries that sort before the
1066 * prefix the tree is spliced into. Note that o->merge
1067 * is always true in this case.
1068 */
1069 while (1) {
1070 struct cache_entry *ce = next_cache_entry(o);
1071 if (!ce)
1072 break;
1073 if (ce_in_traverse_path(ce, &info))
1074 break;
1075 if (unpack_index_entry(ce, o) < 0)
1076 goto return_failed;
1077 }
1078 }
1079
1080 if (traverse_trees(len, t, &info) < 0)
1081 goto return_failed;
1082 }
1083
1084 /* Any left-over entries in the index? */
1085 if (o->merge) {
1086 while (1) {
1087 struct cache_entry *ce = next_cache_entry(o);
1088 if (!ce)
1089 break;
1090 if (unpack_index_entry(ce, o) < 0)
1091 goto return_failed;
1092 }
1093 }
1094 mark_all_ce_unused(o->src_index);
1095
1096 if (o->trivial_merges_only && o->nontrivial_merge) {
1097 ret = unpack_failed(o, "Merge requires file-level merging");
1098 goto done;
1099 }
1100
1101 if (!o->skip_sparse_checkout) {
1102 int empty_worktree = 1;
1103
1104 /*
1105 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1106 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1107 * so apply_sparse_checkout() won't attempt to remove it from worktree
1108 */
1109 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1110
1111 ret = 0;
1112 for (i = 0; i < o->result.cache_nr; i++) {
1113 struct cache_entry *ce = o->result.cache[i];
1114
1115 /*
1116 * Entries marked with CE_ADDED in merged_entry() do not have
1117 * verify_absent() check (the check is effectively disabled
1118 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1119 *
1120 * Do the real check now because we have had
1121 * correct CE_NEW_SKIP_WORKTREE
1122 */
1123 if (ce->ce_flags & CE_ADDED &&
1124 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1125 if (!o->show_all_errors)
1126 goto return_failed;
1127 ret = -1;
1128 }
1129
1130 if (apply_sparse_checkout(ce, o)) {
1131 if (!o->show_all_errors)
1132 goto return_failed;
1133 ret = -1;
1134 }
1135 if (!ce_skip_worktree(ce))
1136 empty_worktree = 0;
1137
1138 }
1139 if (ret < 0)
1140 goto return_failed;
1141 /*
1142 * Sparse checkout is meant to narrow down checkout area
1143 * but it does not make sense to narrow down to empty working
1144 * tree. This is usually a mistake in sparse checkout rules.
1145 * Do not allow users to do that.
1146 */
1147 if (o->result.cache_nr && empty_worktree) {
1148 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1149 goto done;
1150 }
1151 }
1152
1153 o->src_index = NULL;
1154 ret = check_updates(o) ? (-2) : 0;
1155 if (o->dst_index)
1156 *o->dst_index = o->result;
1157
1158 done:
1159 clear_exclude_list(&el);
1160 return ret;
1161
1162 return_failed:
1163 if (o->show_all_errors)
1164 display_error_msgs(o);
1165 mark_all_ce_unused(o->src_index);
1166 ret = unpack_failed(o, NULL);
1167 if (o->exiting_early)
1168 ret = 0;
1169 goto done;
1170 }
1171
1172 /* Here come the merge functions */
1173
1174 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
1175 {
1176 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1177 }
1178
1179 static int same(struct cache_entry *a, struct cache_entry *b)
1180 {
1181 if (!!a != !!b)
1182 return 0;
1183 if (!a && !b)
1184 return 1;
1185 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1186 return 0;
1187 return a->ce_mode == b->ce_mode &&
1188 !hashcmp(a->sha1, b->sha1);
1189 }
1190
1191
1192 /*
1193 * When a CE gets turned into an unmerged entry, we
1194 * want it to be up-to-date
1195 */
1196 static int verify_uptodate_1(struct cache_entry *ce,
1197 struct unpack_trees_options *o,
1198 enum unpack_trees_error_types error_type)
1199 {
1200 struct stat st;
1201
1202 if (o->index_only)
1203 return 0;
1204
1205 /*
1206 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1207 * if this entry is truly up-to-date because this file may be
1208 * overwritten.
1209 */
1210 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1211 ; /* keep checking */
1212 else if (o->reset || ce_uptodate(ce))
1213 return 0;
1214
1215 if (!lstat(ce->name, &st)) {
1216 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1217 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1218 if (!changed)
1219 return 0;
1220 /*
1221 * NEEDSWORK: the current default policy is to allow
1222 * submodule to be out of sync wrt the superproject
1223 * index. This needs to be tightened later for
1224 * submodules that are marked to be automatically
1225 * checked out.
1226 */
1227 if (S_ISGITLINK(ce->ce_mode))
1228 return 0;
1229 errno = 0;
1230 }
1231 if (errno == ENOENT)
1232 return 0;
1233 return o->gently ? -1 :
1234 add_rejected_path(o, error_type, ce->name);
1235 }
1236
1237 static int verify_uptodate(struct cache_entry *ce,
1238 struct unpack_trees_options *o)
1239 {
1240 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1241 return 0;
1242 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1243 }
1244
1245 static int verify_uptodate_sparse(struct cache_entry *ce,
1246 struct unpack_trees_options *o)
1247 {
1248 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1249 }
1250
1251 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
1252 {
1253 if (ce)
1254 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
1255 }
1256
1257 /*
1258 * Check that checking out ce->sha1 in subdir ce->name is not
1259 * going to overwrite any working files.
1260 *
1261 * Currently, git does not checkout subprojects during a superproject
1262 * checkout, so it is not going to overwrite anything.
1263 */
1264 static int verify_clean_submodule(struct cache_entry *ce,
1265 enum unpack_trees_error_types error_type,
1266 struct unpack_trees_options *o)
1267 {
1268 return 0;
1269 }
1270
1271 static int verify_clean_subdirectory(struct cache_entry *ce,
1272 enum unpack_trees_error_types error_type,
1273 struct unpack_trees_options *o)
1274 {
1275 /*
1276 * we are about to extract "ce->name"; we would not want to lose
1277 * anything in the existing directory there.
1278 */
1279 int namelen;
1280 int i;
1281 struct dir_struct d;
1282 char *pathbuf;
1283 int cnt = 0;
1284 unsigned char sha1[20];
1285
1286 if (S_ISGITLINK(ce->ce_mode) &&
1287 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1288 /* If we are not going to update the submodule, then
1289 * we don't care.
1290 */
1291 if (!hashcmp(sha1, ce->sha1))
1292 return 0;
1293 return verify_clean_submodule(ce, error_type, o);
1294 }
1295
1296 /*
1297 * First let's make sure we do not have a local modification
1298 * in that directory.
1299 */
1300 namelen = ce_namelen(ce);
1301 for (i = locate_in_src_index(ce, o);
1302 i < o->src_index->cache_nr;
1303 i++) {
1304 struct cache_entry *ce2 = o->src_index->cache[i];
1305 int len = ce_namelen(ce2);
1306 if (len < namelen ||
1307 strncmp(ce->name, ce2->name, namelen) ||
1308 ce2->name[namelen] != '/')
1309 break;
1310 /*
1311 * ce2->name is an entry in the subdirectory to be
1312 * removed.
1313 */
1314 if (!ce_stage(ce2)) {
1315 if (verify_uptodate(ce2, o))
1316 return -1;
1317 add_entry(o, ce2, CE_REMOVE, 0);
1318 mark_ce_used(ce2, o);
1319 }
1320 cnt++;
1321 }
1322
1323 /*
1324 * Then we need to make sure that we do not lose a locally
1325 * present file that is not ignored.
1326 */
1327 pathbuf = xmalloc(namelen + 2);
1328 memcpy(pathbuf, ce->name, namelen);
1329 strcpy(pathbuf+namelen, "/");
1330
1331 memset(&d, 0, sizeof(d));
1332 if (o->dir)
1333 d.exclude_per_dir = o->dir->exclude_per_dir;
1334 i = read_directory(&d, pathbuf, namelen+1, NULL);
1335 if (i)
1336 return o->gently ? -1 :
1337 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1338 free(pathbuf);
1339 return cnt;
1340 }
1341
1342 /*
1343 * This gets called when there was no index entry for the tree entry 'dst',
1344 * but we found a file in the working tree that 'lstat()' said was fine,
1345 * and we're on a case-insensitive filesystem.
1346 *
1347 * See if we can find a case-insensitive match in the index that also
1348 * matches the stat information, and assume it's that other file!
1349 */
1350 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1351 {
1352 struct cache_entry *src;
1353
1354 src = index_name_exists(o->src_index, name, len, 1);
1355 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1356 }
1357
1358 static int check_ok_to_remove(const char *name, int len, int dtype,
1359 struct cache_entry *ce, struct stat *st,
1360 enum unpack_trees_error_types error_type,
1361 struct unpack_trees_options *o)
1362 {
1363 struct cache_entry *result;
1364
1365 /*
1366 * It may be that the 'lstat()' succeeded even though
1367 * target 'ce' was absent, because there is an old
1368 * entry that is different only in case..
1369 *
1370 * Ignore that lstat() if it matches.
1371 */
1372 if (ignore_case && icase_exists(o, name, len, st))
1373 return 0;
1374
1375 if (o->dir &&
1376 is_excluded(o->dir, name, &dtype))
1377 /*
1378 * ce->name is explicitly excluded, so it is Ok to
1379 * overwrite it.
1380 */
1381 return 0;
1382 if (S_ISDIR(st->st_mode)) {
1383 /*
1384 * We are checking out path "foo" and
1385 * found "foo/." in the working tree.
1386 * This is tricky -- if we have modified
1387 * files that are in "foo/" we would lose
1388 * them.
1389 */
1390 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1391 return -1;
1392 return 0;
1393 }
1394
1395 /*
1396 * The previous round may already have decided to
1397 * delete this path, which is in a subdirectory that
1398 * is being replaced with a blob.
1399 */
1400 result = index_name_exists(&o->result, name, len, 0);
1401 if (result) {
1402 if (result->ce_flags & CE_REMOVE)
1403 return 0;
1404 }
1405
1406 return o->gently ? -1 :
1407 add_rejected_path(o, error_type, name);
1408 }
1409
1410 /*
1411 * We do not want to remove or overwrite a working tree file that
1412 * is not tracked, unless it is ignored.
1413 */
1414 static int verify_absent_1(struct cache_entry *ce,
1415 enum unpack_trees_error_types error_type,
1416 struct unpack_trees_options *o)
1417 {
1418 int len;
1419 struct stat st;
1420
1421 if (o->index_only || o->reset || !o->update)
1422 return 0;
1423
1424 len = check_leading_path(ce->name, ce_namelen(ce));
1425 if (!len)
1426 return 0;
1427 else if (len > 0) {
1428 char path[PATH_MAX + 1];
1429 memcpy(path, ce->name, len);
1430 path[len] = 0;
1431 if (lstat(path, &st))
1432 return error("cannot stat '%s': %s", path,
1433 strerror(errno));
1434
1435 return check_ok_to_remove(path, len, DT_UNKNOWN, NULL, &st,
1436 error_type, o);
1437 } else if (lstat(ce->name, &st)) {
1438 if (errno != ENOENT)
1439 return error("cannot stat '%s': %s", ce->name,
1440 strerror(errno));
1441 return 0;
1442 } else {
1443 return check_ok_to_remove(ce->name, ce_namelen(ce),
1444 ce_to_dtype(ce), ce, &st,
1445 error_type, o);
1446 }
1447 }
1448
1449 static int verify_absent(struct cache_entry *ce,
1450 enum unpack_trees_error_types error_type,
1451 struct unpack_trees_options *o)
1452 {
1453 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1454 return 0;
1455 return verify_absent_1(ce, error_type, o);
1456 }
1457
1458 static int verify_absent_sparse(struct cache_entry *ce,
1459 enum unpack_trees_error_types error_type,
1460 struct unpack_trees_options *o)
1461 {
1462 enum unpack_trees_error_types orphaned_error = error_type;
1463 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1464 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1465
1466 return verify_absent_1(ce, orphaned_error, o);
1467 }
1468
1469 static int merged_entry(const struct cache_entry *ce,
1470 struct cache_entry *old,
1471 struct unpack_trees_options *o)
1472 {
1473 int update = CE_UPDATE;
1474 struct cache_entry *merge = dup_entry(ce);
1475
1476 if (!old) {
1477 /*
1478 * New index entries. In sparse checkout, the following
1479 * verify_absent() will be delayed until after
1480 * traverse_trees() finishes in unpack_trees(), then:
1481 *
1482 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1483 * - verify_absent() be called again, this time with
1484 * correct CE_NEW_SKIP_WORKTREE
1485 *
1486 * verify_absent() call here does nothing in sparse
1487 * checkout (i.e. o->skip_sparse_checkout == 0)
1488 */
1489 update |= CE_ADDED;
1490 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
1491
1492 if (verify_absent(merge,
1493 ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1494 free(merge);
1495 return -1;
1496 }
1497 invalidate_ce_path(merge, o);
1498 } else if (!(old->ce_flags & CE_CONFLICTED)) {
1499 /*
1500 * See if we can re-use the old CE directly?
1501 * That way we get the uptodate stat info.
1502 *
1503 * This also removes the UPDATE flag on a match; otherwise
1504 * we will end up overwriting local changes in the work tree.
1505 */
1506 if (same(old, merge)) {
1507 copy_cache_entry(merge, old);
1508 update = 0;
1509 } else {
1510 if (verify_uptodate(old, o)) {
1511 free(merge);
1512 return -1;
1513 }
1514 /* Migrate old flags over */
1515 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1516 invalidate_ce_path(old, o);
1517 }
1518 } else {
1519 /*
1520 * Previously unmerged entry left as an existence
1521 * marker by read_index_unmerged();
1522 */
1523 invalidate_ce_path(old, o);
1524 }
1525
1526 do_add_entry(o, merge, update, CE_STAGEMASK);
1527 return 1;
1528 }
1529
1530 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1531 struct unpack_trees_options *o)
1532 {
1533 /* Did it exist in the index? */
1534 if (!old) {
1535 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1536 return -1;
1537 return 0;
1538 }
1539 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
1540 return -1;
1541 add_entry(o, ce, CE_REMOVE, 0);
1542 invalidate_ce_path(ce, o);
1543 return 1;
1544 }
1545
1546 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
1547 {
1548 add_entry(o, ce, 0, 0);
1549 return 1;
1550 }
1551
1552 #if DBRT_DEBUG
1553 static void show_stage_entry(FILE *o,
1554 const char *label, const struct cache_entry *ce)
1555 {
1556 if (!ce)
1557 fprintf(o, "%s (missing)\n", label);
1558 else
1559 fprintf(o, "%s%06o %s %d\t%s\n",
1560 label,
1561 ce->ce_mode,
1562 sha1_to_hex(ce->sha1),
1563 ce_stage(ce),
1564 ce->name);
1565 }
1566 #endif
1567
1568 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
1569 {
1570 struct cache_entry *index;
1571 struct cache_entry *head;
1572 struct cache_entry *remote = stages[o->head_idx + 1];
1573 int count;
1574 int head_match = 0;
1575 int remote_match = 0;
1576
1577 int df_conflict_head = 0;
1578 int df_conflict_remote = 0;
1579
1580 int any_anc_missing = 0;
1581 int no_anc_exists = 1;
1582 int i;
1583
1584 for (i = 1; i < o->head_idx; i++) {
1585 if (!stages[i] || stages[i] == o->df_conflict_entry)
1586 any_anc_missing = 1;
1587 else
1588 no_anc_exists = 0;
1589 }
1590
1591 index = stages[0];
1592 head = stages[o->head_idx];
1593
1594 if (head == o->df_conflict_entry) {
1595 df_conflict_head = 1;
1596 head = NULL;
1597 }
1598
1599 if (remote == o->df_conflict_entry) {
1600 df_conflict_remote = 1;
1601 remote = NULL;
1602 }
1603
1604 /*
1605 * First, if there's a #16 situation, note that to prevent #13
1606 * and #14.
1607 */
1608 if (!same(remote, head)) {
1609 for (i = 1; i < o->head_idx; i++) {
1610 if (same(stages[i], head)) {
1611 head_match = i;
1612 }
1613 if (same(stages[i], remote)) {
1614 remote_match = i;
1615 }
1616 }
1617 }
1618
1619 /*
1620 * We start with cases where the index is allowed to match
1621 * something other than the head: #14(ALT) and #2ALT, where it
1622 * is permitted to match the result instead.
1623 */
1624 /* #14, #14ALT, #2ALT */
1625 if (remote && !df_conflict_head && head_match && !remote_match) {
1626 if (index && !same(index, remote) && !same(index, head))
1627 return o->gently ? -1 : reject_merge(index, o);
1628 return merged_entry(remote, index, o);
1629 }
1630 /*
1631 * If we have an entry in the index cache, then we want to
1632 * make sure that it matches head.
1633 */
1634 if (index && !same(index, head))
1635 return o->gently ? -1 : reject_merge(index, o);
1636
1637 if (head) {
1638 /* #5ALT, #15 */
1639 if (same(head, remote))
1640 return merged_entry(head, index, o);
1641 /* #13, #3ALT */
1642 if (!df_conflict_remote && remote_match && !head_match)
1643 return merged_entry(head, index, o);
1644 }
1645
1646 /* #1 */
1647 if (!head && !remote && any_anc_missing)
1648 return 0;
1649
1650 /*
1651 * Under the "aggressive" rule, we resolve mostly trivial
1652 * cases that we historically had git-merge-one-file resolve.
1653 */
1654 if (o->aggressive) {
1655 int head_deleted = !head;
1656 int remote_deleted = !remote;
1657 struct cache_entry *ce = NULL;
1658
1659 if (index)
1660 ce = index;
1661 else if (head)
1662 ce = head;
1663 else if (remote)
1664 ce = remote;
1665 else {
1666 for (i = 1; i < o->head_idx; i++) {
1667 if (stages[i] && stages[i] != o->df_conflict_entry) {
1668 ce = stages[i];
1669 break;
1670 }
1671 }
1672 }
1673
1674 /*
1675 * Deleted in both.
1676 * Deleted in one and unchanged in the other.
1677 */
1678 if ((head_deleted && remote_deleted) ||
1679 (head_deleted && remote && remote_match) ||
1680 (remote_deleted && head && head_match)) {
1681 if (index)
1682 return deleted_entry(index, index, o);
1683 if (ce && !head_deleted) {
1684 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1685 return -1;
1686 }
1687 return 0;
1688 }
1689 /*
1690 * Added in both, identically.
1691 */
1692 if (no_anc_exists && head && remote && same(head, remote))
1693 return merged_entry(head, index, o);
1694
1695 }
1696
1697 /* Below are "no merge" cases, which require that the index be
1698 * up-to-date to avoid the files getting overwritten with
1699 * conflict resolution files.
1700 */
1701 if (index) {
1702 if (verify_uptodate(index, o))
1703 return -1;
1704 }
1705
1706 o->nontrivial_merge = 1;
1707
1708 /* #2, #3, #4, #6, #7, #9, #10, #11. */
1709 count = 0;
1710 if (!head_match || !remote_match) {
1711 for (i = 1; i < o->head_idx; i++) {
1712 if (stages[i] && stages[i] != o->df_conflict_entry) {
1713 keep_entry(stages[i], o);
1714 count++;
1715 break;
1716 }
1717 }
1718 }
1719 #if DBRT_DEBUG
1720 else {
1721 fprintf(stderr, "read-tree: warning #16 detected\n");
1722 show_stage_entry(stderr, "head ", stages[head_match]);
1723 show_stage_entry(stderr, "remote ", stages[remote_match]);
1724 }
1725 #endif
1726 if (head) { count += keep_entry(head, o); }
1727 if (remote) { count += keep_entry(remote, o); }
1728 return count;
1729 }
1730
1731 /*
1732 * Two-way merge.
1733 *
1734 * The rule is to "carry forward" what is in the index without losing
1735 * information across a "fast-forward", favoring a successful merge
1736 * over a merge failure when it makes sense. For details of the
1737 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1738 *
1739 */
1740 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1741 {
1742 struct cache_entry *current = src[0];
1743 struct cache_entry *oldtree = src[1];
1744 struct cache_entry *newtree = src[2];
1745
1746 if (o->merge_size != 2)
1747 return error("Cannot do a twoway merge of %d trees",
1748 o->merge_size);
1749
1750 if (oldtree == o->df_conflict_entry)
1751 oldtree = NULL;
1752 if (newtree == o->df_conflict_entry)
1753 newtree = NULL;
1754
1755 if (current) {
1756 if ((!oldtree && !newtree) || /* 4 and 5 */
1757 (!oldtree && newtree &&
1758 same(current, newtree)) || /* 6 and 7 */
1759 (oldtree && newtree &&
1760 same(oldtree, newtree)) || /* 14 and 15 */
1761 (oldtree && newtree &&
1762 !same(oldtree, newtree) && /* 18 and 19 */
1763 same(current, newtree))) {
1764 return keep_entry(current, o);
1765 }
1766 else if (oldtree && !newtree && same(current, oldtree)) {
1767 /* 10 or 11 */
1768 return deleted_entry(oldtree, current, o);
1769 }
1770 else if (oldtree && newtree &&
1771 same(current, oldtree) && !same(current, newtree)) {
1772 /* 20 or 21 */
1773 return merged_entry(newtree, current, o);
1774 }
1775 else {
1776 /* all other failures */
1777 if (oldtree)
1778 return o->gently ? -1 : reject_merge(oldtree, o);
1779 if (current)
1780 return o->gently ? -1 : reject_merge(current, o);
1781 if (newtree)
1782 return o->gently ? -1 : reject_merge(newtree, o);
1783 return -1;
1784 }
1785 }
1786 else if (newtree) {
1787 if (oldtree && !o->initial_checkout) {
1788 /*
1789 * deletion of the path was staged;
1790 */
1791 if (same(oldtree, newtree))
1792 return 1;
1793 return reject_merge(oldtree, o);
1794 }
1795 return merged_entry(newtree, current, o);
1796 }
1797 return deleted_entry(oldtree, current, o);
1798 }
1799
1800 /*
1801 * Bind merge.
1802 *
1803 * Keep the index entries at stage0, collapse stage1 but make sure
1804 * stage0 does not have anything there.
1805 */
1806 int bind_merge(struct cache_entry **src,
1807 struct unpack_trees_options *o)
1808 {
1809 struct cache_entry *old = src[0];
1810 struct cache_entry *a = src[1];
1811
1812 if (o->merge_size != 1)
1813 return error("Cannot do a bind merge of %d trees",
1814 o->merge_size);
1815 if (a && old)
1816 return o->gently ? -1 :
1817 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
1818 if (!a)
1819 return keep_entry(old, o);
1820 else
1821 return merged_entry(a, NULL, o);
1822 }
1823
1824 /*
1825 * One-way merge.
1826 *
1827 * The rule is:
1828 * - take the stat information from stage0, take the data from stage1
1829 */
1830 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1831 {
1832 struct cache_entry *old = src[0];
1833 struct cache_entry *a = src[1];
1834
1835 if (o->merge_size != 1)
1836 return error("Cannot do a oneway merge of %d trees",
1837 o->merge_size);
1838
1839 if (!a || a == o->df_conflict_entry)
1840 return deleted_entry(old, old, o);
1841
1842 if (old && same(old, a)) {
1843 int update = 0;
1844 if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
1845 struct stat st;
1846 if (lstat(old->name, &st) ||
1847 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
1848 update |= CE_UPDATE;
1849 }
1850 add_entry(o, old, update, 0);
1851 return 0;
1852 }
1853 return merged_entry(a, old, o);
1854 }