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"
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.",
23 /* ERROR_NOT_UPTODATE_FILE */
24 "Entry '%s' not uptodate. Cannot merge.",
26 /* ERROR_NOT_UPTODATE_DIR */
27 "Updating '%s' would lose untracked files in it",
29 /* ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN */
30 "Untracked working tree file '%s' would be overwritten by merge.",
32 /* ERROR_WOULD_LOSE_UNTRACKED_REMOVED */
33 "Untracked working tree file '%s' would be removed by merge.",
35 /* ERROR_BIND_OVERLAP */
36 "Entry '%s' overlaps with '%s'. Cannot bind.",
38 /* ERROR_SPARSE_NOT_UPTODATE_FILE */
39 "Entry '%s' not uptodate. Cannot update sparse checkout.",
41 /* ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN */
42 "Working tree file '%s' would be overwritten by sparse checkout update.",
44 /* ERROR_WOULD_LOSE_ORPHANED_REMOVED */
45 "Working tree file '%s' would be removed by sparse checkout update.",
46 };
48 #define ERRORMSG(o,type) \
49 ( ((o) && (o)->msgs[(type)]) \
50 ? ((o)->msgs[(type)]) \
51 : (unpack_plumbing_errors[(type)]) )
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;
71 msgs[ERROR_NOT_UPTODATE_DIR] =
72 "Updating the following directories would lose untracked files in it:\n%s";
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;
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.";
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";
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 }
105 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
106 unsigned int set, unsigned int clear)
107 {
108 unsigned int size = ce_size(ce);
109 struct cache_entry *new = xmalloc(size);
111 clear |= CE_HASHED | CE_UNHASHED;
113 if (set & CE_REMOVE)
114 set |= CE_WT_REMOVE;
116 memcpy(new, ce, size);
117 new->next = NULL;
118 new->ce_flags = (new->ce_flags & ~clear) | set;
119 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
120 }
122 /*
123 * add error messages on path <path>
124 * corresponding to the type <e> with the message <msg>
125 * indicating if it should be display in porcelain or not
126 */
127 static int add_rejected_path(struct unpack_trees_options *o,
128 enum unpack_trees_error_types e,
129 const char *path)
130 {
131 if (!o->show_all_errors)
132 return error(ERRORMSG(o, e), path);
134 /*
135 * Otherwise, insert in a list for future display by
136 * display_error_msgs()
137 */
138 string_list_append(&o->unpack_rejects[e], path);
139 return -1;
140 }
142 /*
143 * display all the error messages stored in a nice way
144 */
145 static void display_error_msgs(struct unpack_trees_options *o)
146 {
147 int e, i;
148 int something_displayed = 0;
149 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
150 struct string_list *rejects = &o->unpack_rejects[e];
151 if (rejects->nr > 0) {
152 struct strbuf path = STRBUF_INIT;
153 something_displayed = 1;
154 for (i = 0; i < rejects->nr; i++)
155 strbuf_addf(&path, "\t%s\n", rejects->items[i].string);
156 error(ERRORMSG(o, e), path.buf);
157 strbuf_release(&path);
158 }
159 string_list_clear(rejects, 0);
160 }
161 if (something_displayed)
162 printf("Aborting\n");
163 }
165 /*
166 * Unlink the last component and schedule the leading directories for
167 * removal, such that empty directories get removed.
168 */
169 static void unlink_entry(struct cache_entry *ce)
170 {
171 if (!check_leading_path(ce->name, ce_namelen(ce)))
172 return;
173 if (remove_or_warn(ce->ce_mode, ce->name))
174 return;
175 schedule_dir_for_removal(ce->name, ce_namelen(ce));
176 }
178 static struct checkout state;
179 static int check_updates(struct unpack_trees_options *o)
180 {
181 unsigned cnt = 0, total = 0;
182 struct progress *progress = NULL;
183 struct index_state *index = &o->result;
184 int i;
185 int errs = 0;
187 if (o->update && o->verbose_update) {
188 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
189 struct cache_entry *ce = index->cache[cnt];
190 if (ce->ce_flags & (CE_UPDATE | CE_WT_REMOVE))
191 total++;
192 }
194 progress = start_progress_delay("Checking out files",
195 total, 50, 1);
196 cnt = 0;
197 }
199 if (o->update)
200 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
201 for (i = 0; i < index->cache_nr; i++) {
202 struct cache_entry *ce = index->cache[i];
204 if (ce->ce_flags & CE_WT_REMOVE) {
205 display_progress(progress, ++cnt);
206 if (o->update)
207 unlink_entry(ce);
208 continue;
209 }
210 }
211 remove_marked_cache_entries(&o->result);
212 remove_scheduled_dirs();
214 for (i = 0; i < index->cache_nr; i++) {
215 struct cache_entry *ce = index->cache[i];
217 if (ce->ce_flags & CE_UPDATE) {
218 display_progress(progress, ++cnt);
219 ce->ce_flags &= ~CE_UPDATE;
220 if (o->update) {
221 errs |= checkout_entry(ce, &state, NULL);
222 }
223 }
224 }
225 stop_progress(&progress);
226 if (o->update)
227 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
228 return errs != 0;
229 }
231 static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
232 static int verify_absent_sparse(struct cache_entry *ce, enum unpack_trees_error_types, struct unpack_trees_options *o);
234 static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
235 {
236 int was_skip_worktree = ce_skip_worktree(ce);
238 if (ce->ce_flags & CE_NEW_SKIP_WORKTREE)
239 ce->ce_flags |= CE_SKIP_WORKTREE;
240 else
241 ce->ce_flags &= ~CE_SKIP_WORKTREE;
243 /*
244 * if (!was_skip_worktree && !ce_skip_worktree()) {
245 * This is perfectly normal. Move on;
246 * }
247 */
249 /*
250 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
251 * area as a result of ce_skip_worktree() shortcuts in
252 * verify_absent() and verify_uptodate().
253 * Make sure they don't modify worktree if they are already
254 * outside checkout area
255 */
256 if (was_skip_worktree && ce_skip_worktree(ce)) {
257 ce->ce_flags &= ~CE_UPDATE;
259 /*
260 * By default, when CE_REMOVE is on, CE_WT_REMOVE is also
261 * on to get that file removed from both index and worktree.
262 * If that file is already outside worktree area, don't
263 * bother remove it.
264 */
265 if (ce->ce_flags & CE_REMOVE)
266 ce->ce_flags &= ~CE_WT_REMOVE;
267 }
269 if (!was_skip_worktree && ce_skip_worktree(ce)) {
270 /*
271 * If CE_UPDATE is set, verify_uptodate() must be called already
272 * also stat info may have lost after merged_entry() so calling
273 * verify_uptodate() again may fail
274 */
275 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
276 return -1;
277 ce->ce_flags |= CE_WT_REMOVE;
278 }
279 if (was_skip_worktree && !ce_skip_worktree(ce)) {
280 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
281 return -1;
282 ce->ce_flags |= CE_UPDATE;
283 }
284 return 0;
285 }
287 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
288 {
289 int ret = o->fn(src, o);
290 if (ret > 0)
291 ret = 0;
292 return ret;
293 }
295 static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
296 {
297 ce->ce_flags |= CE_UNPACKED;
299 if (o->cache_bottom < o->src_index->cache_nr &&
300 o->src_index->cache[o->cache_bottom] == ce) {
301 int bottom = o->cache_bottom;
302 while (bottom < o->src_index->cache_nr &&
303 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
304 bottom++;
305 o->cache_bottom = bottom;
306 }
307 }
309 static void mark_all_ce_unused(struct index_state *index)
310 {
311 int i;
312 for (i = 0; i < index->cache_nr; i++)
313 index->cache[i]->ce_flags &= ~(CE_UNPACKED | CE_ADDED | CE_NEW_SKIP_WORKTREE);
314 }
316 static int locate_in_src_index(struct cache_entry *ce,
317 struct unpack_trees_options *o)
318 {
319 struct index_state *index = o->src_index;
320 int len = ce_namelen(ce);
321 int pos = index_name_pos(index, ce->name, len);
322 if (pos < 0)
323 pos = -1 - pos;
324 return pos;
325 }
327 /*
328 * We call unpack_index_entry() with an unmerged cache entry
329 * only in diff-index, and it wants a single callback. Skip
330 * the other unmerged entry with the same name.
331 */
332 static void mark_ce_used_same_name(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;
339 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
340 struct cache_entry *next = index->cache[pos];
341 if (len != ce_namelen(next) ||
342 memcmp(ce->name, next->name, len))
343 break;
344 mark_ce_used(next, o);
345 }
346 }
348 static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
349 {
350 const struct index_state *index = o->src_index;
351 int pos = o->cache_bottom;
353 while (pos < index->cache_nr) {
354 struct cache_entry *ce = index->cache[pos];
355 if (!(ce->ce_flags & CE_UNPACKED))
356 return ce;
357 pos++;
358 }
359 return NULL;
360 }
362 static void add_same_unmerged(struct cache_entry *ce,
363 struct unpack_trees_options *o)
364 {
365 struct index_state *index = o->src_index;
366 int len = ce_namelen(ce);
367 int pos = index_name_pos(index, ce->name, len);
369 if (0 <= pos)
370 die("programming error in a caller of mark_ce_used_same_name");
371 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
372 struct cache_entry *next = index->cache[pos];
373 if (len != ce_namelen(next) ||
374 memcmp(ce->name, next->name, len))
375 break;
376 add_entry(o, next, 0, 0);
377 mark_ce_used(next, o);
378 }
379 }
381 static int unpack_index_entry(struct cache_entry *ce,
382 struct unpack_trees_options *o)
383 {
384 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
385 int ret;
387 src[0] = ce;
389 mark_ce_used(ce, o);
390 if (ce_stage(ce)) {
391 if (o->skip_unmerged) {
392 add_entry(o, ce, 0, 0);
393 return 0;
394 }
395 }
396 ret = call_unpack_fn(src, o);
397 if (ce_stage(ce))
398 mark_ce_used_same_name(ce, o);
399 return ret;
400 }
402 static int find_cache_pos(struct traverse_info *, const struct name_entry *);
404 static void restore_cache_bottom(struct traverse_info *info, int bottom)
405 {
406 struct unpack_trees_options *o = info->data;
408 if (o->diff_index_cached)
409 return;
410 o->cache_bottom = bottom;
411 }
413 static int switch_cache_bottom(struct traverse_info *info)
414 {
415 struct unpack_trees_options *o = info->data;
416 int ret, pos;
418 if (o->diff_index_cached)
419 return 0;
420 ret = o->cache_bottom;
421 pos = find_cache_pos(info->prev, &info->name);
423 if (pos < -1)
424 o->cache_bottom = -2 - pos;
425 else if (pos < 0)
426 o->cache_bottom = o->src_index->cache_nr;
427 return ret;
428 }
430 static int traverse_trees_recursive(int n, unsigned long dirmask,
431 unsigned long df_conflicts,
432 struct name_entry *names,
433 struct traverse_info *info)
434 {
435 int i, ret, bottom;
436 struct tree_desc t[MAX_UNPACK_TREES];
437 void *buf[MAX_UNPACK_TREES];
438 struct traverse_info newinfo;
439 struct name_entry *p;
441 p = names;
442 while (!p->mode)
443 p++;
445 newinfo = *info;
446 newinfo.prev = info;
447 newinfo.name = *p;
448 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
449 newinfo.conflicts |= df_conflicts;
451 for (i = 0; i < n; i++, dirmask >>= 1) {
452 const unsigned char *sha1 = NULL;
453 if (dirmask & 1)
454 sha1 = names[i].sha1;
455 buf[i] = fill_tree_descriptor(t+i, sha1);
456 }
458 bottom = switch_cache_bottom(&newinfo);
459 ret = traverse_trees(n, t, &newinfo);
460 restore_cache_bottom(&newinfo, bottom);
462 for (i = 0; i < n; i++)
463 free(buf[i]);
465 return ret;
466 }
468 /*
469 * Compare the traverse-path to the cache entry without actually
470 * having to generate the textual representation of the traverse
471 * path.
472 *
473 * NOTE! This *only* compares up to the size of the traverse path
474 * itself - the caller needs to do the final check for the cache
475 * entry having more data at the end!
476 */
477 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
478 {
479 int len, pathlen, ce_len;
480 const char *ce_name;
482 if (info->prev) {
483 int cmp = do_compare_entry(ce, info->prev, &info->name);
484 if (cmp)
485 return cmp;
486 }
487 pathlen = info->pathlen;
488 ce_len = ce_namelen(ce);
490 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
491 if (ce_len < pathlen)
492 return -1;
494 ce_len -= pathlen;
495 ce_name = ce->name + pathlen;
497 len = tree_entry_len(n->path, n->sha1);
498 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
499 }
501 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
502 {
503 int cmp = do_compare_entry(ce, info, n);
504 if (cmp)
505 return cmp;
507 /*
508 * Even if the beginning compared identically, the ce should
509 * compare as bigger than a directory leading up to it!
510 */
511 return ce_namelen(ce) > traverse_path_len(info, n);
512 }
514 static int ce_in_traverse_path(const struct cache_entry *ce,
515 const struct traverse_info *info)
516 {
517 if (!info->prev)
518 return 1;
519 if (do_compare_entry(ce, info->prev, &info->name))
520 return 0;
521 /*
522 * If ce (blob) is the same name as the path (which is a tree
523 * we will be descending into), it won't be inside it.
524 */
525 return (info->pathlen < ce_namelen(ce));
526 }
528 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
529 {
530 int len = traverse_path_len(info, n);
531 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
533 ce->ce_mode = create_ce_mode(n->mode);
534 ce->ce_flags = create_ce_flags(len, stage);
535 hashcpy(ce->sha1, n->sha1);
536 make_traverse_path(ce->name, info, n);
538 return ce;
539 }
541 static int unpack_nondirectories(int n, unsigned long mask,
542 unsigned long dirmask,
543 struct cache_entry **src,
544 const struct name_entry *names,
545 const struct traverse_info *info)
546 {
547 int i;
548 struct unpack_trees_options *o = info->data;
549 unsigned long conflicts;
551 /* Do we have *only* directories? Nothing to do */
552 if (mask == dirmask && !src[0])
553 return 0;
555 conflicts = info->conflicts;
556 if (o->merge)
557 conflicts >>= 1;
558 conflicts |= dirmask;
560 /*
561 * Ok, we've filled in up to any potential index entry in src[0],
562 * now do the rest.
563 */
564 for (i = 0; i < n; i++) {
565 int stage;
566 unsigned int bit = 1ul << i;
567 if (conflicts & bit) {
568 src[i + o->merge] = o->df_conflict_entry;
569 continue;
570 }
571 if (!(mask & bit))
572 continue;
573 if (!o->merge)
574 stage = 0;
575 else if (i + 1 < o->head_idx)
576 stage = 1;
577 else if (i + 1 > o->head_idx)
578 stage = 3;
579 else
580 stage = 2;
581 src[i + o->merge] = create_ce_entry(info, names + i, stage);
582 }
584 if (o->merge)
585 return call_unpack_fn(src, o);
587 for (i = 0; i < n; i++)
588 if (src[i] && src[i] != o->df_conflict_entry)
589 add_entry(o, src[i], 0, 0);
590 return 0;
591 }
593 static int unpack_failed(struct unpack_trees_options *o, const char *message)
594 {
595 discard_index(&o->result);
596 if (!o->gently && !o->exiting_early) {
597 if (message)
598 return error("%s", message);
599 return -1;
600 }
601 return -1;
602 }
604 /* NEEDSWORK: give this a better name and share with tree-walk.c */
605 static int name_compare(const char *a, int a_len,
606 const char *b, int b_len)
607 {
608 int len = (a_len < b_len) ? a_len : b_len;
609 int cmp = memcmp(a, b, len);
610 if (cmp)
611 return cmp;
612 return (a_len - b_len);
613 }
615 /*
616 * The tree traversal is looking at name p. If we have a matching entry,
617 * return it. If name p is a directory in the index, do not return
618 * anything, as we will want to match it when the traversal descends into
619 * the directory.
620 */
621 static int find_cache_pos(struct traverse_info *info,
622 const struct name_entry *p)
623 {
624 int pos;
625 struct unpack_trees_options *o = info->data;
626 struct index_state *index = o->src_index;
627 int pfxlen = info->pathlen;
628 int p_len = tree_entry_len(p->path, p->sha1);
630 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
631 struct cache_entry *ce = index->cache[pos];
632 const char *ce_name, *ce_slash;
633 int cmp, ce_len;
635 if (ce->ce_flags & CE_UNPACKED) {
636 /*
637 * cache_bottom entry is already unpacked, so
638 * we can never match it; don't check it
639 * again.
640 */
641 if (pos == o->cache_bottom)
642 ++o->cache_bottom;
643 continue;
644 }
645 if (!ce_in_traverse_path(ce, info))
646 continue;
647 ce_name = ce->name + pfxlen;
648 ce_slash = strchr(ce_name, '/');
649 if (ce_slash)
650 ce_len = ce_slash - ce_name;
651 else
652 ce_len = ce_namelen(ce) - pfxlen;
653 cmp = name_compare(p->path, p_len, ce_name, ce_len);
654 /*
655 * Exact match; if we have a directory we need to
656 * delay returning it.
657 */
658 if (!cmp)
659 return ce_slash ? -2 - pos : pos;
660 if (0 < cmp)
661 continue; /* keep looking */
662 /*
663 * ce_name sorts after p->path; could it be that we
664 * have files under p->path directory in the index?
665 * E.g. ce_name == "t-i", and p->path == "t"; we may
666 * have "t/a" in the index.
667 */
668 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
669 ce_name[p_len] < '/')
670 continue; /* keep looking */
671 break;
672 }
673 return -1;
674 }
676 static struct cache_entry *find_cache_entry(struct traverse_info *info,
677 const struct name_entry *p)
678 {
679 int pos = find_cache_pos(info, p);
680 struct unpack_trees_options *o = info->data;
682 if (0 <= pos)
683 return o->src_index->cache[pos];
684 else
685 return NULL;
686 }
688 static void debug_path(struct traverse_info *info)
689 {
690 if (info->prev) {
691 debug_path(info->prev);
692 if (*info->prev->name.path)
693 putchar('/');
694 }
695 printf("%s", info->name.path);
696 }
698 static void debug_name_entry(int i, struct name_entry *n)
699 {
700 printf("ent#%d %06o %s\n", i,
701 n->path ? n->mode : 0,
702 n->path ? n->path : "(missing)");
703 }
705 static void debug_unpack_callback(int n,
706 unsigned long mask,
707 unsigned long dirmask,
708 struct name_entry *names,
709 struct traverse_info *info)
710 {
711 int i;
712 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
713 mask, dirmask, n);
714 debug_path(info);
715 putchar('\n');
716 for (i = 0; i < n; i++)
717 debug_name_entry(i, names + i);
718 }
720 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
721 {
722 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
723 struct unpack_trees_options *o = info->data;
724 const struct name_entry *p = names;
726 /* Find first entry with a real name (we could use "mask" too) */
727 while (!p->mode)
728 p++;
730 if (o->debug_unpack)
731 debug_unpack_callback(n, mask, dirmask, names, info);
733 /* Are we supposed to look at the index too? */
734 if (o->merge) {
735 while (1) {
736 int cmp;
737 struct cache_entry *ce;
739 if (o->diff_index_cached)
740 ce = next_cache_entry(o);
741 else
742 ce = find_cache_entry(info, p);
744 if (!ce)
745 break;
746 cmp = compare_entry(ce, info, p);
747 if (cmp < 0) {
748 if (unpack_index_entry(ce, o) < 0)
749 return unpack_failed(o, NULL);
750 continue;
751 }
752 if (!cmp) {
753 if (ce_stage(ce)) {
754 /*
755 * If we skip unmerged index
756 * entries, we'll skip this
757 * entry *and* the tree
758 * entries associated with it!
759 */
760 if (o->skip_unmerged) {
761 add_same_unmerged(ce, o);
762 return mask;
763 }
764 }
765 src[0] = ce;
766 }
767 break;
768 }
769 }
771 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
772 return -1;
774 if (src[0]) {
775 if (ce_stage(src[0]))
776 mark_ce_used_same_name(src[0], o);
777 else
778 mark_ce_used(src[0], o);
779 }
781 /* Now handle any directories.. */
782 if (dirmask) {
783 unsigned long conflicts = mask & ~dirmask;
784 if (o->merge) {
785 conflicts <<= 1;
786 if (src[0])
787 conflicts |= 1;
788 }
790 /* special case: "diff-index --cached" looking at a tree */
791 if (o->diff_index_cached &&
792 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
793 int matches;
794 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
795 names, info);
796 /*
797 * Everything under the name matches; skip the
798 * entire hierarchy. diff_index_cached codepath
799 * special cases D/F conflicts in such a way that
800 * it does not do any look-ahead, so this is safe.
801 */
802 if (matches) {
803 o->cache_bottom += matches;
804 return mask;
805 }
806 }
808 if (traverse_trees_recursive(n, dirmask, conflicts,
809 names, info) < 0)
810 return -1;
811 return mask;
812 }
814 return mask;
815 }
817 /* Whole directory matching */
818 static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
819 char *prefix, int prefix_len,
820 char *basename,
821 int select_mask, int clear_mask,
822 struct exclude_list *el)
823 {
824 struct cache_entry **cache_end = cache + nr;
825 int dtype = DT_DIR;
826 int ret = excluded_from_list(prefix, prefix_len, basename, &dtype, el);
828 prefix[prefix_len++] = '/';
830 /* included, no clearing for any entries under this directory */
831 if (!ret) {
832 for (; cache != cache_end; cache++) {
833 struct cache_entry *ce = *cache;
834 if (strncmp(ce->name, prefix, prefix_len))
835 break;
836 }
837 return nr - (cache_end - cache);
838 }
840 /* excluded, clear all selected entries under this directory. */
841 if (ret == 1) {
842 for (; cache != cache_end; cache++) {
843 struct cache_entry *ce = *cache;
844 if (select_mask && !(ce->ce_flags & select_mask))
845 continue;
846 if (strncmp(ce->name, prefix, prefix_len))
847 break;
848 ce->ce_flags &= ~clear_mask;
849 }
850 return nr - (cache_end - cache);
851 }
853 return 0;
854 }
856 /*
857 * Traverse the index, find every entry that matches according to
858 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
859 * number of traversed entries.
860 *
861 * If select_mask is non-zero, only entries whose ce_flags has on of
862 * those bits enabled are traversed.
863 *
864 * cache : pointer to an index entry
865 * prefix_len : an offset to its path
866 *
867 * The current path ("prefix") including the trailing '/' is
868 * cache[0]->name[0..(prefix_len-1)]
869 * Top level path has prefix_len zero.
870 */
871 static int clear_ce_flags_1(struct cache_entry **cache, int nr,
872 char *prefix, int prefix_len,
873 int select_mask, int clear_mask,
874 struct exclude_list *el)
875 {
876 struct cache_entry **cache_end = cache + nr;
878 /*
879 * Process all entries that have the given prefix and meet
880 * select_mask condition
881 */
882 while(cache != cache_end) {
883 struct cache_entry *ce = *cache;
884 const char *name, *slash;
885 int len, dtype;
887 if (select_mask && !(ce->ce_flags & select_mask)) {
888 cache++;
889 continue;
890 }
892 if (prefix_len && strncmp(ce->name, prefix, prefix_len))
893 break;
895 name = ce->name + prefix_len;
896 slash = strchr(name, '/');
898 /* If it's a directory, try whole directory match first */
899 if (slash) {
900 int processed;
902 len = slash - name;
903 memcpy(prefix + prefix_len, name, len);
905 /*
906 * terminate the string (no trailing slash),
907 * clear_c_f_dir needs it
908 */
909 prefix[prefix_len + len] = '\0';
910 processed = clear_ce_flags_dir(cache, cache_end - cache,
911 prefix, prefix_len + len,
912 prefix + prefix_len,
913 select_mask, clear_mask,
914 el);
916 /* clear_c_f_dir eats a whole dir already? */
917 if (processed) {
918 cache += processed;
919 continue;
920 }
922 prefix[prefix_len + len++] = '/';
923 cache += clear_ce_flags_1(cache, cache_end - cache,
924 prefix, prefix_len + len,
925 select_mask, clear_mask, el);
926 continue;
927 }
929 /* Non-directory */
930 dtype = ce_to_dtype(ce);
931 if (excluded_from_list(ce->name, ce_namelen(ce), name, &dtype, el) > 0)
932 ce->ce_flags &= ~clear_mask;
933 cache++;
934 }
935 return nr - (cache_end - cache);
936 }
938 static int clear_ce_flags(struct cache_entry **cache, int nr,
939 int select_mask, int clear_mask,
940 struct exclude_list *el)
941 {
942 char prefix[PATH_MAX];
943 return clear_ce_flags_1(cache, nr,
944 prefix, 0,
945 select_mask, clear_mask,
946 el);
947 }
949 /*
950 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
951 */
952 static void mark_new_skip_worktree(struct exclude_list *el,
953 struct index_state *the_index,
954 int select_flag, int skip_wt_flag)
955 {
956 int i;
958 /*
959 * 1. Pretend the narrowest worktree: only unmerged entries
960 * are checked out
961 */
962 for (i = 0; i < the_index->cache_nr; i++) {
963 struct cache_entry *ce = the_index->cache[i];
965 if (select_flag && !(ce->ce_flags & select_flag))
966 continue;
968 if (!ce_stage(ce))
969 ce->ce_flags |= skip_wt_flag;
970 else
971 ce->ce_flags &= ~skip_wt_flag;
972 }
974 /*
975 * 2. Widen worktree according to sparse-checkout file.
976 * Matched entries will have skip_wt_flag cleared (i.e. "in")
977 */
978 clear_ce_flags(the_index->cache, the_index->cache_nr,
979 select_flag, skip_wt_flag, el);
980 }
982 static int verify_absent(struct cache_entry *, enum unpack_trees_error_types, struct unpack_trees_options *);
983 /*
984 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
985 * resulting index, -2 on failure to reflect the changes to the work tree.
986 *
987 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
988 */
989 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
990 {
991 int i, ret;
992 static struct cache_entry *dfc;
993 struct exclude_list el;
995 if (len > MAX_UNPACK_TREES)
996 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
997 memset(&state, 0, sizeof(state));
998 state.base_dir = "";
999 state.force = 1;
1000 state.quiet = 1;
1001 state.refresh_cache = 1;
1003 memset(&el, 0, sizeof(el));
1004 if (!core_apply_sparse_checkout || !o->update)
1005 o->skip_sparse_checkout = 1;
1006 if (!o->skip_sparse_checkout) {
1007 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
1008 o->skip_sparse_checkout = 1;
1009 else
1010 o->el = ⪙
1011 }
1013 memset(&o->result, 0, sizeof(o->result));
1014 o->result.initialized = 1;
1015 o->result.timestamp.sec = o->src_index->timestamp.sec;
1016 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1017 o->merge_size = len;
1018 mark_all_ce_unused(o->src_index);
1020 /*
1021 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1022 */
1023 if (!o->skip_sparse_checkout)
1024 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1026 if (!dfc)
1027 dfc = xcalloc(1, cache_entry_size(0));
1028 o->df_conflict_entry = dfc;
1030 if (len) {
1031 const char *prefix = o->prefix ? o->prefix : "";
1032 struct traverse_info info;
1034 setup_traverse_info(&info, prefix);
1035 info.fn = unpack_callback;
1036 info.data = o;
1037 info.show_all_errors = o->show_all_errors;
1039 if (o->prefix) {
1040 /*
1041 * Unpack existing index entries that sort before the
1042 * prefix the tree is spliced into. Note that o->merge
1043 * is always true in this case.
1044 */
1045 while (1) {
1046 struct cache_entry *ce = next_cache_entry(o);
1047 if (!ce)
1048 break;
1049 if (ce_in_traverse_path(ce, &info))
1050 break;
1051 if (unpack_index_entry(ce, o) < 0)
1052 goto return_failed;
1053 }
1054 }
1056 if (traverse_trees(len, t, &info) < 0)
1057 goto return_failed;
1058 }
1060 /* Any left-over entries in the index? */
1061 if (o->merge) {
1062 while (1) {
1063 struct cache_entry *ce = next_cache_entry(o);
1064 if (!ce)
1065 break;
1066 if (unpack_index_entry(ce, o) < 0)
1067 goto return_failed;
1068 }
1069 }
1070 mark_all_ce_unused(o->src_index);
1072 if (o->trivial_merges_only && o->nontrivial_merge) {
1073 ret = unpack_failed(o, "Merge requires file-level merging");
1074 goto done;
1075 }
1077 if (!o->skip_sparse_checkout) {
1078 int empty_worktree = 1;
1080 /*
1081 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1082 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1083 * so apply_sparse_checkout() won't attempt to remove it from worktree
1084 */
1085 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1087 for (i = 0; i < o->result.cache_nr; i++) {
1088 struct cache_entry *ce = o->result.cache[i];
1090 /*
1091 * Entries marked with CE_ADDED in merged_entry() do not have
1092 * verify_absent() check (the check is effectively disabled
1093 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1094 *
1095 * Do the real check now because we have had
1096 * correct CE_NEW_SKIP_WORKTREE
1097 */
1098 if (ce->ce_flags & CE_ADDED &&
1099 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
1100 return -1;
1102 if (apply_sparse_checkout(ce, o)) {
1103 ret = -1;
1104 goto done;
1105 }
1106 if (!ce_skip_worktree(ce))
1107 empty_worktree = 0;
1109 }
1110 if (o->result.cache_nr && empty_worktree) {
1111 /* dubious---why should this fail??? */
1112 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1113 goto done;
1114 }
1115 }
1117 o->src_index = NULL;
1118 ret = check_updates(o) ? (-2) : 0;
1119 if (o->dst_index)
1120 *o->dst_index = o->result;
1122 done:
1123 free_excludes(&el);
1124 return ret;
1126 return_failed:
1127 if (o->show_all_errors)
1128 display_error_msgs(o);
1129 mark_all_ce_unused(o->src_index);
1130 ret = unpack_failed(o, NULL);
1131 if (o->exiting_early)
1132 ret = 0;
1133 goto done;
1134 }
1136 /* Here come the merge functions */
1138 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
1139 {
1140 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1141 }
1143 static int same(struct cache_entry *a, struct cache_entry *b)
1144 {
1145 if (!!a != !!b)
1146 return 0;
1147 if (!a && !b)
1148 return 1;
1149 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1150 return 0;
1151 return a->ce_mode == b->ce_mode &&
1152 !hashcmp(a->sha1, b->sha1);
1153 }
1156 /*
1157 * When a CE gets turned into an unmerged entry, we
1158 * want it to be up-to-date
1159 */
1160 static int verify_uptodate_1(struct cache_entry *ce,
1161 struct unpack_trees_options *o,
1162 enum unpack_trees_error_types error_type)
1163 {
1164 struct stat st;
1166 if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
1167 return 0;
1169 if (!lstat(ce->name, &st)) {
1170 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1171 if (!changed)
1172 return 0;
1173 /*
1174 * NEEDSWORK: the current default policy is to allow
1175 * submodule to be out of sync wrt the supermodule
1176 * index. This needs to be tightened later for
1177 * submodules that are marked to be automatically
1178 * checked out.
1179 */
1180 if (S_ISGITLINK(ce->ce_mode))
1181 return 0;
1182 errno = 0;
1183 }
1184 if (errno == ENOENT)
1185 return 0;
1186 return o->gently ? -1 :
1187 add_rejected_path(o, error_type, ce->name);
1188 }
1190 static int verify_uptodate(struct cache_entry *ce,
1191 struct unpack_trees_options *o)
1192 {
1193 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1194 return 0;
1195 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1196 }
1198 static int verify_uptodate_sparse(struct cache_entry *ce,
1199 struct unpack_trees_options *o)
1200 {
1201 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1202 }
1204 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
1205 {
1206 if (ce)
1207 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
1208 }
1210 /*
1211 * Check that checking out ce->sha1 in subdir ce->name is not
1212 * going to overwrite any working files.
1213 *
1214 * Currently, git does not checkout subprojects during a superproject
1215 * checkout, so it is not going to overwrite anything.
1216 */
1217 static int verify_clean_submodule(struct cache_entry *ce,
1218 enum unpack_trees_error_types error_type,
1219 struct unpack_trees_options *o)
1220 {
1221 return 0;
1222 }
1224 static int verify_clean_subdirectory(struct cache_entry *ce,
1225 enum unpack_trees_error_types error_type,
1226 struct unpack_trees_options *o)
1227 {
1228 /*
1229 * we are about to extract "ce->name"; we would not want to lose
1230 * anything in the existing directory there.
1231 */
1232 int namelen;
1233 int i;
1234 struct dir_struct d;
1235 char *pathbuf;
1236 int cnt = 0;
1237 unsigned char sha1[20];
1239 if (S_ISGITLINK(ce->ce_mode) &&
1240 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1241 /* If we are not going to update the submodule, then
1242 * we don't care.
1243 */
1244 if (!hashcmp(sha1, ce->sha1))
1245 return 0;
1246 return verify_clean_submodule(ce, error_type, o);
1247 }
1249 /*
1250 * First let's make sure we do not have a local modification
1251 * in that directory.
1252 */
1253 namelen = strlen(ce->name);
1254 for (i = locate_in_src_index(ce, o);
1255 i < o->src_index->cache_nr;
1256 i++) {
1257 struct cache_entry *ce2 = o->src_index->cache[i];
1258 int len = ce_namelen(ce2);
1259 if (len < namelen ||
1260 strncmp(ce->name, ce2->name, namelen) ||
1261 ce2->name[namelen] != '/')
1262 break;
1263 /*
1264 * ce2->name is an entry in the subdirectory to be
1265 * removed.
1266 */
1267 if (!ce_stage(ce2)) {
1268 if (verify_uptodate(ce2, o))
1269 return -1;
1270 add_entry(o, ce2, CE_REMOVE, 0);
1271 mark_ce_used(ce2, o);
1272 }
1273 cnt++;
1274 }
1276 /*
1277 * Then we need to make sure that we do not lose a locally
1278 * present file that is not ignored.
1279 */
1280 pathbuf = xmalloc(namelen + 2);
1281 memcpy(pathbuf, ce->name, namelen);
1282 strcpy(pathbuf+namelen, "/");
1284 memset(&d, 0, sizeof(d));
1285 if (o->dir)
1286 d.exclude_per_dir = o->dir->exclude_per_dir;
1287 i = read_directory(&d, pathbuf, namelen+1, NULL);
1288 if (i)
1289 return o->gently ? -1 :
1290 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1291 free(pathbuf);
1292 return cnt;
1293 }
1295 /*
1296 * This gets called when there was no index entry for the tree entry 'dst',
1297 * but we found a file in the working tree that 'lstat()' said was fine,
1298 * and we're on a case-insensitive filesystem.
1299 *
1300 * See if we can find a case-insensitive match in the index that also
1301 * matches the stat information, and assume it's that other file!
1302 */
1303 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1304 {
1305 struct cache_entry *src;
1307 src = index_name_exists(o->src_index, name, len, 1);
1308 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1309 }
1311 static int check_ok_to_remove(const char *name, int len, int dtype,
1312 struct cache_entry *ce, struct stat *st,
1313 enum unpack_trees_error_types error_type,
1314 struct unpack_trees_options *o)
1315 {
1316 struct cache_entry *result;
1318 /*
1319 * It may be that the 'lstat()' succeeded even though
1320 * target 'ce' was absent, because there is an old
1321 * entry that is different only in case..
1322 *
1323 * Ignore that lstat() if it matches.
1324 */
1325 if (ignore_case && icase_exists(o, name, len, st))
1326 return 0;
1328 if (o->dir && excluded(o->dir, name, &dtype))
1329 /*
1330 * ce->name is explicitly excluded, so it is Ok to
1331 * overwrite it.
1332 */
1333 return 0;
1334 if (S_ISDIR(st->st_mode)) {
1335 /*
1336 * We are checking out path "foo" and
1337 * found "foo/." in the working tree.
1338 * This is tricky -- if we have modified
1339 * files that are in "foo/" we would lose
1340 * them.
1341 */
1342 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1343 return -1;
1344 return 0;
1345 }
1347 /*
1348 * The previous round may already have decided to
1349 * delete this path, which is in a subdirectory that
1350 * is being replaced with a blob.
1351 */
1352 result = index_name_exists(&o->result, name, len, 0);
1353 if (result) {
1354 if (result->ce_flags & CE_REMOVE)
1355 return 0;
1356 }
1358 return o->gently ? -1 :
1359 add_rejected_path(o, error_type, name);
1360 }
1362 /*
1363 * We do not want to remove or overwrite a working tree file that
1364 * is not tracked, unless it is ignored.
1365 */
1366 static int verify_absent_1(struct cache_entry *ce,
1367 enum unpack_trees_error_types error_type,
1368 struct unpack_trees_options *o)
1369 {
1370 int len;
1371 struct stat st;
1373 if (o->index_only || o->reset || !o->update)
1374 return 0;
1376 len = check_leading_path(ce->name, ce_namelen(ce));
1377 if (!len)
1378 return 0;
1379 else if (len > 0) {
1380 char path[PATH_MAX + 1];
1381 memcpy(path, ce->name, len);
1382 path[len] = 0;
1383 if (lstat(path, &st))
1384 return error("cannot stat '%s': %s", path,
1385 strerror(errno));
1387 return check_ok_to_remove(path, len, DT_UNKNOWN, NULL, &st,
1388 error_type, o);
1389 } else if (lstat(ce->name, &st)) {
1390 if (errno != ENOENT)
1391 return error("cannot stat '%s': %s", ce->name,
1392 strerror(errno));
1393 return 0;
1394 } else {
1395 return check_ok_to_remove(ce->name, ce_namelen(ce),
1396 ce_to_dtype(ce), ce, &st,
1397 error_type, o);
1398 }
1399 }
1401 static int verify_absent(struct cache_entry *ce,
1402 enum unpack_trees_error_types error_type,
1403 struct unpack_trees_options *o)
1404 {
1405 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1406 return 0;
1407 return verify_absent_1(ce, error_type, o);
1408 }
1410 static int verify_absent_sparse(struct cache_entry *ce,
1411 enum unpack_trees_error_types error_type,
1412 struct unpack_trees_options *o)
1413 {
1414 enum unpack_trees_error_types orphaned_error = error_type;
1415 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1416 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1418 return verify_absent_1(ce, orphaned_error, o);
1419 }
1421 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
1422 struct unpack_trees_options *o)
1423 {
1424 int update = CE_UPDATE;
1426 if (!old) {
1427 /*
1428 * New index entries. In sparse checkout, the following
1429 * verify_absent() will be delayed until after
1430 * traverse_trees() finishes in unpack_trees(), then:
1431 *
1432 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1433 * - verify_absent() be called again, this time with
1434 * correct CE_NEW_SKIP_WORKTREE
1435 *
1436 * verify_absent() call here does nothing in sparse
1437 * checkout (i.e. o->skip_sparse_checkout == 0)
1438 */
1439 update |= CE_ADDED;
1440 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
1442 if (verify_absent(merge, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
1443 return -1;
1444 invalidate_ce_path(merge, o);
1445 } else if (!(old->ce_flags & CE_CONFLICTED)) {
1446 /*
1447 * See if we can re-use the old CE directly?
1448 * That way we get the uptodate stat info.
1449 *
1450 * This also removes the UPDATE flag on a match; otherwise
1451 * we will end up overwriting local changes in the work tree.
1452 */
1453 if (same(old, merge)) {
1454 copy_cache_entry(merge, old);
1455 update = 0;
1456 } else {
1457 if (verify_uptodate(old, o))
1458 return -1;
1459 /* Migrate old flags over */
1460 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1461 invalidate_ce_path(old, o);
1462 }
1463 } else {
1464 /*
1465 * Previously unmerged entry left as an existence
1466 * marker by read_index_unmerged();
1467 */
1468 invalidate_ce_path(old, o);
1469 }
1471 add_entry(o, merge, update, CE_STAGEMASK);
1472 return 1;
1473 }
1475 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1476 struct unpack_trees_options *o)
1477 {
1478 /* Did it exist in the index? */
1479 if (!old) {
1480 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1481 return -1;
1482 return 0;
1483 }
1484 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
1485 return -1;
1486 add_entry(o, ce, CE_REMOVE, 0);
1487 invalidate_ce_path(ce, o);
1488 return 1;
1489 }
1491 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
1492 {
1493 add_entry(o, ce, 0, 0);
1494 return 1;
1495 }
1497 #if DBRT_DEBUG
1498 static void show_stage_entry(FILE *o,
1499 const char *label, const struct cache_entry *ce)
1500 {
1501 if (!ce)
1502 fprintf(o, "%s (missing)\n", label);
1503 else
1504 fprintf(o, "%s%06o %s %d\t%s\n",
1505 label,
1506 ce->ce_mode,
1507 sha1_to_hex(ce->sha1),
1508 ce_stage(ce),
1509 ce->name);
1510 }
1511 #endif
1513 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
1514 {
1515 struct cache_entry *index;
1516 struct cache_entry *head;
1517 struct cache_entry *remote = stages[o->head_idx + 1];
1518 int count;
1519 int head_match = 0;
1520 int remote_match = 0;
1522 int df_conflict_head = 0;
1523 int df_conflict_remote = 0;
1525 int any_anc_missing = 0;
1526 int no_anc_exists = 1;
1527 int i;
1529 for (i = 1; i < o->head_idx; i++) {
1530 if (!stages[i] || stages[i] == o->df_conflict_entry)
1531 any_anc_missing = 1;
1532 else
1533 no_anc_exists = 0;
1534 }
1536 index = stages[0];
1537 head = stages[o->head_idx];
1539 if (head == o->df_conflict_entry) {
1540 df_conflict_head = 1;
1541 head = NULL;
1542 }
1544 if (remote == o->df_conflict_entry) {
1545 df_conflict_remote = 1;
1546 remote = NULL;
1547 }
1549 /*
1550 * First, if there's a #16 situation, note that to prevent #13
1551 * and #14.
1552 */
1553 if (!same(remote, head)) {
1554 for (i = 1; i < o->head_idx; i++) {
1555 if (same(stages[i], head)) {
1556 head_match = i;
1557 }
1558 if (same(stages[i], remote)) {
1559 remote_match = i;
1560 }
1561 }
1562 }
1564 /*
1565 * We start with cases where the index is allowed to match
1566 * something other than the head: #14(ALT) and #2ALT, where it
1567 * is permitted to match the result instead.
1568 */
1569 /* #14, #14ALT, #2ALT */
1570 if (remote && !df_conflict_head && head_match && !remote_match) {
1571 if (index && !same(index, remote) && !same(index, head))
1572 return o->gently ? -1 : reject_merge(index, o);
1573 return merged_entry(remote, index, o);
1574 }
1575 /*
1576 * If we have an entry in the index cache, then we want to
1577 * make sure that it matches head.
1578 */
1579 if (index && !same(index, head))
1580 return o->gently ? -1 : reject_merge(index, o);
1582 if (head) {
1583 /* #5ALT, #15 */
1584 if (same(head, remote))
1585 return merged_entry(head, index, o);
1586 /* #13, #3ALT */
1587 if (!df_conflict_remote && remote_match && !head_match)
1588 return merged_entry(head, index, o);
1589 }
1591 /* #1 */
1592 if (!head && !remote && any_anc_missing)
1593 return 0;
1595 /*
1596 * Under the "aggressive" rule, we resolve mostly trivial
1597 * cases that we historically had git-merge-one-file resolve.
1598 */
1599 if (o->aggressive) {
1600 int head_deleted = !head;
1601 int remote_deleted = !remote;
1602 struct cache_entry *ce = NULL;
1604 if (index)
1605 ce = index;
1606 else if (head)
1607 ce = head;
1608 else if (remote)
1609 ce = remote;
1610 else {
1611 for (i = 1; i < o->head_idx; i++) {
1612 if (stages[i] && stages[i] != o->df_conflict_entry) {
1613 ce = stages[i];
1614 break;
1615 }
1616 }
1617 }
1619 /*
1620 * Deleted in both.
1621 * Deleted in one and unchanged in the other.
1622 */
1623 if ((head_deleted && remote_deleted) ||
1624 (head_deleted && remote && remote_match) ||
1625 (remote_deleted && head && head_match)) {
1626 if (index)
1627 return deleted_entry(index, index, o);
1628 if (ce && !head_deleted) {
1629 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1630 return -1;
1631 }
1632 return 0;
1633 }
1634 /*
1635 * Added in both, identically.
1636 */
1637 if (no_anc_exists && head && remote && same(head, remote))
1638 return merged_entry(head, index, o);
1640 }
1642 /* Below are "no merge" cases, which require that the index be
1643 * up-to-date to avoid the files getting overwritten with
1644 * conflict resolution files.
1645 */
1646 if (index) {
1647 if (verify_uptodate(index, o))
1648 return -1;
1649 }
1651 o->nontrivial_merge = 1;
1653 /* #2, #3, #4, #6, #7, #9, #10, #11. */
1654 count = 0;
1655 if (!head_match || !remote_match) {
1656 for (i = 1; i < o->head_idx; i++) {
1657 if (stages[i] && stages[i] != o->df_conflict_entry) {
1658 keep_entry(stages[i], o);
1659 count++;
1660 break;
1661 }
1662 }
1663 }
1664 #if DBRT_DEBUG
1665 else {
1666 fprintf(stderr, "read-tree: warning #16 detected\n");
1667 show_stage_entry(stderr, "head ", stages[head_match]);
1668 show_stage_entry(stderr, "remote ", stages[remote_match]);
1669 }
1670 #endif
1671 if (head) { count += keep_entry(head, o); }
1672 if (remote) { count += keep_entry(remote, o); }
1673 return count;
1674 }
1676 /*
1677 * Two-way merge.
1678 *
1679 * The rule is to "carry forward" what is in the index without losing
1680 * information across a "fast-forward", favoring a successful merge
1681 * over a merge failure when it makes sense. For details of the
1682 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1683 *
1684 */
1685 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1686 {
1687 struct cache_entry *current = src[0];
1688 struct cache_entry *oldtree = src[1];
1689 struct cache_entry *newtree = src[2];
1691 if (o->merge_size != 2)
1692 return error("Cannot do a twoway merge of %d trees",
1693 o->merge_size);
1695 if (oldtree == o->df_conflict_entry)
1696 oldtree = NULL;
1697 if (newtree == o->df_conflict_entry)
1698 newtree = NULL;
1700 if (current) {
1701 if ((!oldtree && !newtree) || /* 4 and 5 */
1702 (!oldtree && newtree &&
1703 same(current, newtree)) || /* 6 and 7 */
1704 (oldtree && newtree &&
1705 same(oldtree, newtree)) || /* 14 and 15 */
1706 (oldtree && newtree &&
1707 !same(oldtree, newtree) && /* 18 and 19 */
1708 same(current, newtree))) {
1709 return keep_entry(current, o);
1710 }
1711 else if (oldtree && !newtree && same(current, oldtree)) {
1712 /* 10 or 11 */
1713 return deleted_entry(oldtree, current, o);
1714 }
1715 else if (oldtree && newtree &&
1716 same(current, oldtree) && !same(current, newtree)) {
1717 /* 20 or 21 */
1718 return merged_entry(newtree, current, o);
1719 }
1720 else {
1721 /* all other failures */
1722 if (oldtree)
1723 return o->gently ? -1 : reject_merge(oldtree, o);
1724 if (current)
1725 return o->gently ? -1 : reject_merge(current, o);
1726 if (newtree)
1727 return o->gently ? -1 : reject_merge(newtree, o);
1728 return -1;
1729 }
1730 }
1731 else if (newtree) {
1732 if (oldtree && !o->initial_checkout) {
1733 /*
1734 * deletion of the path was staged;
1735 */
1736 if (same(oldtree, newtree))
1737 return 1;
1738 return reject_merge(oldtree, o);
1739 }
1740 return merged_entry(newtree, current, o);
1741 }
1742 return deleted_entry(oldtree, current, o);
1743 }
1745 /*
1746 * Bind merge.
1747 *
1748 * Keep the index entries at stage0, collapse stage1 but make sure
1749 * stage0 does not have anything there.
1750 */
1751 int bind_merge(struct cache_entry **src,
1752 struct unpack_trees_options *o)
1753 {
1754 struct cache_entry *old = src[0];
1755 struct cache_entry *a = src[1];
1757 if (o->merge_size != 1)
1758 return error("Cannot do a bind merge of %d trees\n",
1759 o->merge_size);
1760 if (a && old)
1761 return o->gently ? -1 :
1762 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
1763 if (!a)
1764 return keep_entry(old, o);
1765 else
1766 return merged_entry(a, NULL, o);
1767 }
1769 /*
1770 * One-way merge.
1771 *
1772 * The rule is:
1773 * - take the stat information from stage0, take the data from stage1
1774 */
1775 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1776 {
1777 struct cache_entry *old = src[0];
1778 struct cache_entry *a = src[1];
1780 if (o->merge_size != 1)
1781 return error("Cannot do a oneway merge of %d trees",
1782 o->merge_size);
1784 if (!a || a == o->df_conflict_entry)
1785 return deleted_entry(old, old, o);
1787 if (old && same(old, a)) {
1788 int update = 0;
1789 if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
1790 struct stat st;
1791 if (lstat(old->name, &st) ||
1792 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
1793 update |= CE_UPDATE;
1794 }
1795 add_entry(o, old, update, 0);
1796 return 0;
1797 }
1798 return merged_entry(a, old, o);
1799 }