Merge branch 'bc/submodule-foreach-stdin-fix-1.7.4' into maint
[git/mingw.git] / unpack-trees.c
blobcc616c3f991a655d10fcac15055fcdfafa8620fd
1 #define NO_THE_INDEX_COMPATIBILITY_MACROS
2 #include "cache.h"
3 #include "dir.h"
4 #include "tree.h"
5 #include "tree-walk.h"
6 #include "cache-tree.h"
7 #include "unpack-trees.h"
8 #include "progress.h"
9 #include "refs.h"
10 #include "attr.h"
13 * Error messages expected by scripts out of plumbing commands such as
14 * read-tree. Non-scripted Porcelain is not required to use these messages
15 * and in fact are encouraged to reword them to better suit their particular
16 * situation better. See how "git checkout" and "git merge" replaces
17 * them using setup_unpack_trees_porcelain(), for example.
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.",
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)
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;
87 * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
88 * cannot easily display it as a list.
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;
105 static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
106 unsigned int set, unsigned int clear)
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);
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
127 static int add_rejected_path(struct unpack_trees_options *o,
128 enum unpack_trees_error_types e,
129 const char *path)
131 if (!o->show_all_errors)
132 return error(ERRORMSG(o, e), path);
135 * Otherwise, insert in a list for future display by
136 * display_error_msgs()
138 string_list_append(&o->unpack_rejects[e], path);
139 return -1;
143 * display all the error messages stored in a nice way
145 static void display_error_msgs(struct unpack_trees_options *o)
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);
159 string_list_clear(rejects, 0);
161 if (something_displayed)
162 printf("Aborting\n");
166 * Unlink the last component and schedule the leading directories for
167 * removal, such that empty directories get removed.
169 static void unlink_entry(struct cache_entry *ce)
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));
178 static struct checkout state;
179 static int check_updates(struct unpack_trees_options *o)
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++;
194 progress = start_progress_delay("Checking out files",
195 total, 50, 1);
196 cnt = 0;
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 && !o->dry_run)
207 unlink_entry(ce);
208 continue;
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 && !o->dry_run) {
221 errs |= checkout_entry(ce, &state, NULL);
225 stop_progress(&progress);
226 if (o->update)
227 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
228 return errs != 0;
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)
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;
244 * if (!was_skip_worktree && !ce_skip_worktree()) {
245 * This is perfectly normal. Move on;
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
256 if (was_skip_worktree && ce_skip_worktree(ce)) {
257 ce->ce_flags &= ~CE_UPDATE;
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.
265 if (ce->ce_flags & CE_REMOVE)
266 ce->ce_flags &= ~CE_WT_REMOVE;
269 if (!was_skip_worktree && ce_skip_worktree(ce)) {
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
275 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
276 return -1;
277 ce->ce_flags |= CE_WT_REMOVE;
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;
284 return 0;
287 static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
289 int ret = o->fn(src, o);
290 if (ret > 0)
291 ret = 0;
292 return ret;
295 static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
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;
309 static void mark_all_ce_unused(struct index_state *index)
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);
316 static int locate_in_src_index(struct cache_entry *ce,
317 struct unpack_trees_options *o)
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;
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.
332 static void mark_ce_used_same_name(struct cache_entry *ce,
333 struct unpack_trees_options *o)
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);
348 static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
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++;
359 return NULL;
362 static void add_same_unmerged(struct cache_entry *ce,
363 struct unpack_trees_options *o)
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);
381 static int unpack_index_entry(struct cache_entry *ce,
382 struct unpack_trees_options *o)
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;
396 ret = call_unpack_fn(src, o);
397 if (ce_stage(ce))
398 mark_ce_used_same_name(ce, o);
399 return ret;
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)
406 struct unpack_trees_options *o = info->data;
408 if (o->diff_index_cached)
409 return;
410 o->cache_bottom = bottom;
413 static int switch_cache_bottom(struct traverse_info *info)
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;
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)
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);
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;
469 * Compare the traverse-path to the cache entry without actually
470 * having to generate the textual representation of the traverse
471 * path.
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!
477 static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
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;
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);
501 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
503 int cmp = do_compare_entry(ce, info, n);
504 if (cmp)
505 return cmp;
508 * Even if the beginning compared identically, the ce should
509 * compare as bigger than a directory leading up to it!
511 return ce_namelen(ce) > traverse_path_len(info, n);
514 static int ce_in_traverse_path(const struct cache_entry *ce,
515 const struct traverse_info *info)
517 if (!info->prev)
518 return 1;
519 if (do_compare_entry(ce, info->prev, &info->name))
520 return 0;
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.
525 return (info->pathlen < ce_namelen(ce));
528 static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
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;
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)
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;
561 * Ok, we've filled in up to any potential index entry in src[0],
562 * now do the rest.
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;
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);
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;
593 static int unpack_failed(struct unpack_trees_options *o, const char *message)
595 discard_index(&o->result);
596 if (!o->gently && !o->exiting_early) {
597 if (message)
598 return error("%s", message);
599 return -1;
601 return -1;
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)
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);
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.
621 static int find_cache_pos(struct traverse_info *info,
622 const struct name_entry *p)
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) {
637 * cache_bottom entry is already unpacked, so
638 * we can never match it; don't check it
639 * again.
641 if (pos == o->cache_bottom)
642 ++o->cache_bottom;
643 continue;
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);
655 * Exact match; if we have a directory we need to
656 * delay returning it.
658 if (!cmp)
659 return ce_slash ? -2 - pos : pos;
660 if (0 < cmp)
661 continue; /* keep looking */
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.
668 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
669 ce_name[p_len] < '/')
670 continue; /* keep looking */
671 break;
673 return -1;
676 static struct cache_entry *find_cache_entry(struct traverse_info *info,
677 const struct name_entry *p)
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;
688 static void debug_path(struct traverse_info *info)
690 if (info->prev) {
691 debug_path(info->prev);
692 if (*info->prev->name.path)
693 putchar('/');
695 printf("%s", info->name.path);
698 static void debug_name_entry(int i, struct name_entry *n)
700 printf("ent#%d %06o %s\n", i,
701 n->path ? n->mode : 0,
702 n->path ? n->path : "(missing)");
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)
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);
720 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
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;
752 if (!cmp) {
753 if (ce_stage(ce)) {
755 * If we skip unmerged index
756 * entries, we'll skip this
757 * entry *and* the tree
758 * entries associated with it!
760 if (o->skip_unmerged) {
761 add_same_unmerged(ce, o);
762 return mask;
765 src[0] = ce;
767 break;
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);
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;
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);
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.
802 if (matches) {
803 o->cache_bottom += matches;
804 return mask;
808 if (traverse_trees_recursive(n, dirmask, conflicts,
809 names, info) < 0)
810 return -1;
811 return mask;
814 return mask;
817 static int clear_ce_flags_1(struct cache_entry **cache, int nr,
818 char *prefix, int prefix_len,
819 int select_mask, int clear_mask,
820 struct exclude_list *el, int defval);
822 /* Whole directory matching */
823 static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
824 char *prefix, int prefix_len,
825 char *basename,
826 int select_mask, int clear_mask,
827 struct exclude_list *el, int defval)
829 struct cache_entry **cache_end;
830 int dtype = DT_DIR;
831 int ret = excluded_from_list(prefix, prefix_len, basename, &dtype, el);
833 prefix[prefix_len++] = '/';
835 /* If undecided, use matching result of parent dir in defval */
836 if (ret < 0)
837 ret = defval;
839 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
840 struct cache_entry *ce = *cache_end;
841 if (strncmp(ce->name, prefix, prefix_len))
842 break;
846 * TODO: check el, if there are no patterns that may conflict
847 * with ret (iow, we know in advance the incl/excl
848 * decision for the entire directory), clear flag here without
849 * calling clear_ce_flags_1(). That function will call
850 * the expensive excluded_from_list() on every entry.
852 return clear_ce_flags_1(cache, cache_end - cache,
853 prefix, prefix_len,
854 select_mask, clear_mask,
855 el, ret);
859 * Traverse the index, find every entry that matches according to
860 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
861 * number of traversed entries.
863 * If select_mask is non-zero, only entries whose ce_flags has on of
864 * those bits enabled are traversed.
866 * cache : pointer to an index entry
867 * prefix_len : an offset to its path
869 * The current path ("prefix") including the trailing '/' is
870 * cache[0]->name[0..(prefix_len-1)]
871 * Top level path has prefix_len zero.
873 static int clear_ce_flags_1(struct cache_entry **cache, int nr,
874 char *prefix, int prefix_len,
875 int select_mask, int clear_mask,
876 struct exclude_list *el, int defval)
878 struct cache_entry **cache_end = cache + nr;
881 * Process all entries that have the given prefix and meet
882 * select_mask condition
884 while(cache != cache_end) {
885 struct cache_entry *ce = *cache;
886 const char *name, *slash;
887 int len, dtype, ret;
889 if (select_mask && !(ce->ce_flags & select_mask)) {
890 cache++;
891 continue;
894 if (prefix_len && strncmp(ce->name, prefix, prefix_len))
895 break;
897 name = ce->name + prefix_len;
898 slash = strchr(name, '/');
900 /* If it's a directory, try whole directory match first */
901 if (slash) {
902 int processed;
904 len = slash - name;
905 memcpy(prefix + prefix_len, name, len);
908 * terminate the string (no trailing slash),
909 * clear_c_f_dir needs it
911 prefix[prefix_len + len] = '\0';
912 processed = clear_ce_flags_dir(cache, cache_end - cache,
913 prefix, prefix_len + len,
914 prefix + prefix_len,
915 select_mask, clear_mask,
916 el, defval);
918 /* clear_c_f_dir eats a whole dir already? */
919 if (processed) {
920 cache += processed;
921 continue;
924 prefix[prefix_len + len++] = '/';
925 cache += clear_ce_flags_1(cache, cache_end - cache,
926 prefix, prefix_len + len,
927 select_mask, clear_mask, el, defval);
928 continue;
931 /* Non-directory */
932 dtype = ce_to_dtype(ce);
933 ret = excluded_from_list(ce->name, ce_namelen(ce), name, &dtype, el);
934 if (ret < 0)
935 ret = defval;
936 if (ret > 0)
937 ce->ce_flags &= ~clear_mask;
938 cache++;
940 return nr - (cache_end - cache);
943 static int clear_ce_flags(struct cache_entry **cache, int nr,
944 int select_mask, int clear_mask,
945 struct exclude_list *el)
947 char prefix[PATH_MAX];
948 return clear_ce_flags_1(cache, nr,
949 prefix, 0,
950 select_mask, clear_mask,
951 el, 0);
955 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
957 static void mark_new_skip_worktree(struct exclude_list *el,
958 struct index_state *the_index,
959 int select_flag, int skip_wt_flag)
961 int i;
964 * 1. Pretend the narrowest worktree: only unmerged entries
965 * are checked out
967 for (i = 0; i < the_index->cache_nr; i++) {
968 struct cache_entry *ce = the_index->cache[i];
970 if (select_flag && !(ce->ce_flags & select_flag))
971 continue;
973 if (!ce_stage(ce))
974 ce->ce_flags |= skip_wt_flag;
975 else
976 ce->ce_flags &= ~skip_wt_flag;
980 * 2. Widen worktree according to sparse-checkout file.
981 * Matched entries will have skip_wt_flag cleared (i.e. "in")
983 clear_ce_flags(the_index->cache, the_index->cache_nr,
984 select_flag, skip_wt_flag, el);
987 static int verify_absent(struct cache_entry *, enum unpack_trees_error_types, struct unpack_trees_options *);
989 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
990 * resulting index, -2 on failure to reflect the changes to the work tree.
992 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
994 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
996 int i, ret;
997 static struct cache_entry *dfc;
998 struct exclude_list el;
1000 if (len > MAX_UNPACK_TREES)
1001 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1002 memset(&state, 0, sizeof(state));
1003 state.base_dir = "";
1004 state.force = 1;
1005 state.quiet = 1;
1006 state.refresh_cache = 1;
1008 memset(&el, 0, sizeof(el));
1009 if (!core_apply_sparse_checkout || !o->update)
1010 o->skip_sparse_checkout = 1;
1011 if (!o->skip_sparse_checkout) {
1012 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
1013 o->skip_sparse_checkout = 1;
1014 else
1015 o->el = &el;
1018 memset(&o->result, 0, sizeof(o->result));
1019 o->result.initialized = 1;
1020 o->result.timestamp.sec = o->src_index->timestamp.sec;
1021 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1022 o->merge_size = len;
1023 mark_all_ce_unused(o->src_index);
1026 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1028 if (!o->skip_sparse_checkout)
1029 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1031 if (!dfc)
1032 dfc = xcalloc(1, cache_entry_size(0));
1033 o->df_conflict_entry = dfc;
1035 if (len) {
1036 const char *prefix = o->prefix ? o->prefix : "";
1037 struct traverse_info info;
1039 setup_traverse_info(&info, prefix);
1040 info.fn = unpack_callback;
1041 info.data = o;
1042 info.show_all_errors = o->show_all_errors;
1044 if (o->prefix) {
1046 * Unpack existing index entries that sort before the
1047 * prefix the tree is spliced into. Note that o->merge
1048 * is always true in this case.
1050 while (1) {
1051 struct cache_entry *ce = next_cache_entry(o);
1052 if (!ce)
1053 break;
1054 if (ce_in_traverse_path(ce, &info))
1055 break;
1056 if (unpack_index_entry(ce, o) < 0)
1057 goto return_failed;
1061 if (traverse_trees(len, t, &info) < 0)
1062 goto return_failed;
1065 /* Any left-over entries in the index? */
1066 if (o->merge) {
1067 while (1) {
1068 struct cache_entry *ce = next_cache_entry(o);
1069 if (!ce)
1070 break;
1071 if (unpack_index_entry(ce, o) < 0)
1072 goto return_failed;
1075 mark_all_ce_unused(o->src_index);
1077 if (o->trivial_merges_only && o->nontrivial_merge) {
1078 ret = unpack_failed(o, "Merge requires file-level merging");
1079 goto done;
1082 if (!o->skip_sparse_checkout) {
1083 int empty_worktree = 1;
1086 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1087 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1088 * so apply_sparse_checkout() won't attempt to remove it from worktree
1090 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1092 for (i = 0; i < o->result.cache_nr; i++) {
1093 struct cache_entry *ce = o->result.cache[i];
1096 * Entries marked with CE_ADDED in merged_entry() do not have
1097 * verify_absent() check (the check is effectively disabled
1098 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1100 * Do the real check now because we have had
1101 * correct CE_NEW_SKIP_WORKTREE
1103 if (ce->ce_flags & CE_ADDED &&
1104 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
1105 return -1;
1107 if (apply_sparse_checkout(ce, o)) {
1108 ret = -1;
1109 goto done;
1111 if (!ce_skip_worktree(ce))
1112 empty_worktree = 0;
1115 if (o->result.cache_nr && empty_worktree) {
1116 /* dubious---why should this fail??? */
1117 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1118 goto done;
1122 o->src_index = NULL;
1123 ret = check_updates(o) ? (-2) : 0;
1124 if (o->dst_index)
1125 *o->dst_index = o->result;
1127 done:
1128 free_excludes(&el);
1129 return ret;
1131 return_failed:
1132 if (o->show_all_errors)
1133 display_error_msgs(o);
1134 mark_all_ce_unused(o->src_index);
1135 ret = unpack_failed(o, NULL);
1136 if (o->exiting_early)
1137 ret = 0;
1138 goto done;
1141 /* Here come the merge functions */
1143 static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
1145 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1148 static int same(struct cache_entry *a, struct cache_entry *b)
1150 if (!!a != !!b)
1151 return 0;
1152 if (!a && !b)
1153 return 1;
1154 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1155 return 0;
1156 return a->ce_mode == b->ce_mode &&
1157 !hashcmp(a->sha1, b->sha1);
1162 * When a CE gets turned into an unmerged entry, we
1163 * want it to be up-to-date
1165 static int verify_uptodate_1(struct cache_entry *ce,
1166 struct unpack_trees_options *o,
1167 enum unpack_trees_error_types error_type)
1169 struct stat st;
1171 if (o->index_only)
1172 return 0;
1175 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1176 * if this entry is truly up-to-date because this file may be
1177 * overwritten.
1179 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1180 ; /* keep checking */
1181 else if (o->reset || ce_uptodate(ce))
1182 return 0;
1184 if (!lstat(ce->name, &st)) {
1185 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1186 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1187 if (!changed)
1188 return 0;
1190 * NEEDSWORK: the current default policy is to allow
1191 * submodule to be out of sync wrt the supermodule
1192 * index. This needs to be tightened later for
1193 * submodules that are marked to be automatically
1194 * checked out.
1196 if (S_ISGITLINK(ce->ce_mode))
1197 return 0;
1198 errno = 0;
1200 if (errno == ENOENT)
1201 return 0;
1202 return o->gently ? -1 :
1203 add_rejected_path(o, error_type, ce->name);
1206 static int verify_uptodate(struct cache_entry *ce,
1207 struct unpack_trees_options *o)
1209 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1210 return 0;
1211 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1214 static int verify_uptodate_sparse(struct cache_entry *ce,
1215 struct unpack_trees_options *o)
1217 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1220 static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
1222 if (ce)
1223 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
1227 * Check that checking out ce->sha1 in subdir ce->name is not
1228 * going to overwrite any working files.
1230 * Currently, git does not checkout subprojects during a superproject
1231 * checkout, so it is not going to overwrite anything.
1233 static int verify_clean_submodule(struct cache_entry *ce,
1234 enum unpack_trees_error_types error_type,
1235 struct unpack_trees_options *o)
1237 return 0;
1240 static int verify_clean_subdirectory(struct cache_entry *ce,
1241 enum unpack_trees_error_types error_type,
1242 struct unpack_trees_options *o)
1245 * we are about to extract "ce->name"; we would not want to lose
1246 * anything in the existing directory there.
1248 int namelen;
1249 int i;
1250 struct dir_struct d;
1251 char *pathbuf;
1252 int cnt = 0;
1253 unsigned char sha1[20];
1255 if (S_ISGITLINK(ce->ce_mode) &&
1256 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1257 /* If we are not going to update the submodule, then
1258 * we don't care.
1260 if (!hashcmp(sha1, ce->sha1))
1261 return 0;
1262 return verify_clean_submodule(ce, error_type, o);
1266 * First let's make sure we do not have a local modification
1267 * in that directory.
1269 namelen = strlen(ce->name);
1270 for (i = locate_in_src_index(ce, o);
1271 i < o->src_index->cache_nr;
1272 i++) {
1273 struct cache_entry *ce2 = o->src_index->cache[i];
1274 int len = ce_namelen(ce2);
1275 if (len < namelen ||
1276 strncmp(ce->name, ce2->name, namelen) ||
1277 ce2->name[namelen] != '/')
1278 break;
1280 * ce2->name is an entry in the subdirectory to be
1281 * removed.
1283 if (!ce_stage(ce2)) {
1284 if (verify_uptodate(ce2, o))
1285 return -1;
1286 add_entry(o, ce2, CE_REMOVE, 0);
1287 mark_ce_used(ce2, o);
1289 cnt++;
1293 * Then we need to make sure that we do not lose a locally
1294 * present file that is not ignored.
1296 pathbuf = xmalloc(namelen + 2);
1297 memcpy(pathbuf, ce->name, namelen);
1298 strcpy(pathbuf+namelen, "/");
1300 memset(&d, 0, sizeof(d));
1301 if (o->dir)
1302 d.exclude_per_dir = o->dir->exclude_per_dir;
1303 i = read_directory(&d, pathbuf, namelen+1, NULL);
1304 if (i)
1305 return o->gently ? -1 :
1306 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1307 free(pathbuf);
1308 return cnt;
1312 * This gets called when there was no index entry for the tree entry 'dst',
1313 * but we found a file in the working tree that 'lstat()' said was fine,
1314 * and we're on a case-insensitive filesystem.
1316 * See if we can find a case-insensitive match in the index that also
1317 * matches the stat information, and assume it's that other file!
1319 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1321 struct cache_entry *src;
1323 src = index_name_exists(o->src_index, name, len, 1);
1324 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1327 static int check_ok_to_remove(const char *name, int len, int dtype,
1328 struct cache_entry *ce, struct stat *st,
1329 enum unpack_trees_error_types error_type,
1330 struct unpack_trees_options *o)
1332 struct cache_entry *result;
1335 * It may be that the 'lstat()' succeeded even though
1336 * target 'ce' was absent, because there is an old
1337 * entry that is different only in case..
1339 * Ignore that lstat() if it matches.
1341 if (ignore_case && icase_exists(o, name, len, st))
1342 return 0;
1344 if (o->dir && excluded(o->dir, name, &dtype))
1346 * ce->name is explicitly excluded, so it is Ok to
1347 * overwrite it.
1349 return 0;
1350 if (S_ISDIR(st->st_mode)) {
1352 * We are checking out path "foo" and
1353 * found "foo/." in the working tree.
1354 * This is tricky -- if we have modified
1355 * files that are in "foo/" we would lose
1356 * them.
1358 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1359 return -1;
1360 return 0;
1364 * The previous round may already have decided to
1365 * delete this path, which is in a subdirectory that
1366 * is being replaced with a blob.
1368 result = index_name_exists(&o->result, name, len, 0);
1369 if (result) {
1370 if (result->ce_flags & CE_REMOVE)
1371 return 0;
1374 return o->gently ? -1 :
1375 add_rejected_path(o, error_type, name);
1379 * We do not want to remove or overwrite a working tree file that
1380 * is not tracked, unless it is ignored.
1382 static int verify_absent_1(struct cache_entry *ce,
1383 enum unpack_trees_error_types error_type,
1384 struct unpack_trees_options *o)
1386 int len;
1387 struct stat st;
1389 if (o->index_only || o->reset || !o->update)
1390 return 0;
1392 len = check_leading_path(ce->name, ce_namelen(ce));
1393 if (!len)
1394 return 0;
1395 else if (len > 0) {
1396 char path[PATH_MAX + 1];
1397 memcpy(path, ce->name, len);
1398 path[len] = 0;
1399 if (lstat(path, &st))
1400 return error("cannot stat '%s': %s", path,
1401 strerror(errno));
1403 return check_ok_to_remove(path, len, DT_UNKNOWN, NULL, &st,
1404 error_type, o);
1405 } else if (lstat(ce->name, &st)) {
1406 if (errno != ENOENT)
1407 return error("cannot stat '%s': %s", ce->name,
1408 strerror(errno));
1409 return 0;
1410 } else {
1411 return check_ok_to_remove(ce->name, ce_namelen(ce),
1412 ce_to_dtype(ce), ce, &st,
1413 error_type, o);
1417 static int verify_absent(struct cache_entry *ce,
1418 enum unpack_trees_error_types error_type,
1419 struct unpack_trees_options *o)
1421 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1422 return 0;
1423 return verify_absent_1(ce, error_type, o);
1426 static int verify_absent_sparse(struct cache_entry *ce,
1427 enum unpack_trees_error_types error_type,
1428 struct unpack_trees_options *o)
1430 enum unpack_trees_error_types orphaned_error = error_type;
1431 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1432 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1434 return verify_absent_1(ce, orphaned_error, o);
1437 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
1438 struct unpack_trees_options *o)
1440 int update = CE_UPDATE;
1442 if (!old) {
1444 * New index entries. In sparse checkout, the following
1445 * verify_absent() will be delayed until after
1446 * traverse_trees() finishes in unpack_trees(), then:
1448 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1449 * - verify_absent() be called again, this time with
1450 * correct CE_NEW_SKIP_WORKTREE
1452 * verify_absent() call here does nothing in sparse
1453 * checkout (i.e. o->skip_sparse_checkout == 0)
1455 update |= CE_ADDED;
1456 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
1458 if (verify_absent(merge, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
1459 return -1;
1460 invalidate_ce_path(merge, o);
1461 } else if (!(old->ce_flags & CE_CONFLICTED)) {
1463 * See if we can re-use the old CE directly?
1464 * That way we get the uptodate stat info.
1466 * This also removes the UPDATE flag on a match; otherwise
1467 * we will end up overwriting local changes in the work tree.
1469 if (same(old, merge)) {
1470 copy_cache_entry(merge, old);
1471 update = 0;
1472 } else {
1473 if (verify_uptodate(old, o))
1474 return -1;
1475 /* Migrate old flags over */
1476 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1477 invalidate_ce_path(old, o);
1479 } else {
1481 * Previously unmerged entry left as an existence
1482 * marker by read_index_unmerged();
1484 invalidate_ce_path(old, o);
1487 add_entry(o, merge, update, CE_STAGEMASK);
1488 return 1;
1491 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1492 struct unpack_trees_options *o)
1494 /* Did it exist in the index? */
1495 if (!old) {
1496 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1497 return -1;
1498 return 0;
1500 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
1501 return -1;
1502 add_entry(o, ce, CE_REMOVE, 0);
1503 invalidate_ce_path(ce, o);
1504 return 1;
1507 static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
1509 add_entry(o, ce, 0, 0);
1510 return 1;
1513 #if DBRT_DEBUG
1514 static void show_stage_entry(FILE *o,
1515 const char *label, const struct cache_entry *ce)
1517 if (!ce)
1518 fprintf(o, "%s (missing)\n", label);
1519 else
1520 fprintf(o, "%s%06o %s %d\t%s\n",
1521 label,
1522 ce->ce_mode,
1523 sha1_to_hex(ce->sha1),
1524 ce_stage(ce),
1525 ce->name);
1527 #endif
1529 int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
1531 struct cache_entry *index;
1532 struct cache_entry *head;
1533 struct cache_entry *remote = stages[o->head_idx + 1];
1534 int count;
1535 int head_match = 0;
1536 int remote_match = 0;
1538 int df_conflict_head = 0;
1539 int df_conflict_remote = 0;
1541 int any_anc_missing = 0;
1542 int no_anc_exists = 1;
1543 int i;
1545 for (i = 1; i < o->head_idx; i++) {
1546 if (!stages[i] || stages[i] == o->df_conflict_entry)
1547 any_anc_missing = 1;
1548 else
1549 no_anc_exists = 0;
1552 index = stages[0];
1553 head = stages[o->head_idx];
1555 if (head == o->df_conflict_entry) {
1556 df_conflict_head = 1;
1557 head = NULL;
1560 if (remote == o->df_conflict_entry) {
1561 df_conflict_remote = 1;
1562 remote = NULL;
1566 * First, if there's a #16 situation, note that to prevent #13
1567 * and #14.
1569 if (!same(remote, head)) {
1570 for (i = 1; i < o->head_idx; i++) {
1571 if (same(stages[i], head)) {
1572 head_match = i;
1574 if (same(stages[i], remote)) {
1575 remote_match = i;
1581 * We start with cases where the index is allowed to match
1582 * something other than the head: #14(ALT) and #2ALT, where it
1583 * is permitted to match the result instead.
1585 /* #14, #14ALT, #2ALT */
1586 if (remote && !df_conflict_head && head_match && !remote_match) {
1587 if (index && !same(index, remote) && !same(index, head))
1588 return o->gently ? -1 : reject_merge(index, o);
1589 return merged_entry(remote, index, o);
1592 * If we have an entry in the index cache, then we want to
1593 * make sure that it matches head.
1595 if (index && !same(index, head))
1596 return o->gently ? -1 : reject_merge(index, o);
1598 if (head) {
1599 /* #5ALT, #15 */
1600 if (same(head, remote))
1601 return merged_entry(head, index, o);
1602 /* #13, #3ALT */
1603 if (!df_conflict_remote && remote_match && !head_match)
1604 return merged_entry(head, index, o);
1607 /* #1 */
1608 if (!head && !remote && any_anc_missing)
1609 return 0;
1612 * Under the "aggressive" rule, we resolve mostly trivial
1613 * cases that we historically had git-merge-one-file resolve.
1615 if (o->aggressive) {
1616 int head_deleted = !head;
1617 int remote_deleted = !remote;
1618 struct cache_entry *ce = NULL;
1620 if (index)
1621 ce = index;
1622 else if (head)
1623 ce = head;
1624 else if (remote)
1625 ce = remote;
1626 else {
1627 for (i = 1; i < o->head_idx; i++) {
1628 if (stages[i] && stages[i] != o->df_conflict_entry) {
1629 ce = stages[i];
1630 break;
1636 * Deleted in both.
1637 * Deleted in one and unchanged in the other.
1639 if ((head_deleted && remote_deleted) ||
1640 (head_deleted && remote && remote_match) ||
1641 (remote_deleted && head && head_match)) {
1642 if (index)
1643 return deleted_entry(index, index, o);
1644 if (ce && !head_deleted) {
1645 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1646 return -1;
1648 return 0;
1651 * Added in both, identically.
1653 if (no_anc_exists && head && remote && same(head, remote))
1654 return merged_entry(head, index, o);
1658 /* Below are "no merge" cases, which require that the index be
1659 * up-to-date to avoid the files getting overwritten with
1660 * conflict resolution files.
1662 if (index) {
1663 if (verify_uptodate(index, o))
1664 return -1;
1667 o->nontrivial_merge = 1;
1669 /* #2, #3, #4, #6, #7, #9, #10, #11. */
1670 count = 0;
1671 if (!head_match || !remote_match) {
1672 for (i = 1; i < o->head_idx; i++) {
1673 if (stages[i] && stages[i] != o->df_conflict_entry) {
1674 keep_entry(stages[i], o);
1675 count++;
1676 break;
1680 #if DBRT_DEBUG
1681 else {
1682 fprintf(stderr, "read-tree: warning #16 detected\n");
1683 show_stage_entry(stderr, "head ", stages[head_match]);
1684 show_stage_entry(stderr, "remote ", stages[remote_match]);
1686 #endif
1687 if (head) { count += keep_entry(head, o); }
1688 if (remote) { count += keep_entry(remote, o); }
1689 return count;
1693 * Two-way merge.
1695 * The rule is to "carry forward" what is in the index without losing
1696 * information across a "fast-forward", favoring a successful merge
1697 * over a merge failure when it makes sense. For details of the
1698 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1701 int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1703 struct cache_entry *current = src[0];
1704 struct cache_entry *oldtree = src[1];
1705 struct cache_entry *newtree = src[2];
1707 if (o->merge_size != 2)
1708 return error("Cannot do a twoway merge of %d trees",
1709 o->merge_size);
1711 if (oldtree == o->df_conflict_entry)
1712 oldtree = NULL;
1713 if (newtree == o->df_conflict_entry)
1714 newtree = NULL;
1716 if (current) {
1717 if ((!oldtree && !newtree) || /* 4 and 5 */
1718 (!oldtree && newtree &&
1719 same(current, newtree)) || /* 6 and 7 */
1720 (oldtree && newtree &&
1721 same(oldtree, newtree)) || /* 14 and 15 */
1722 (oldtree && newtree &&
1723 !same(oldtree, newtree) && /* 18 and 19 */
1724 same(current, newtree))) {
1725 return keep_entry(current, o);
1727 else if (oldtree && !newtree && same(current, oldtree)) {
1728 /* 10 or 11 */
1729 return deleted_entry(oldtree, current, o);
1731 else if (oldtree && newtree &&
1732 same(current, oldtree) && !same(current, newtree)) {
1733 /* 20 or 21 */
1734 return merged_entry(newtree, current, o);
1736 else {
1737 /* all other failures */
1738 if (oldtree)
1739 return o->gently ? -1 : reject_merge(oldtree, o);
1740 if (current)
1741 return o->gently ? -1 : reject_merge(current, o);
1742 if (newtree)
1743 return o->gently ? -1 : reject_merge(newtree, o);
1744 return -1;
1747 else if (newtree) {
1748 if (oldtree && !o->initial_checkout) {
1750 * deletion of the path was staged;
1752 if (same(oldtree, newtree))
1753 return 1;
1754 return reject_merge(oldtree, o);
1756 return merged_entry(newtree, current, o);
1758 return deleted_entry(oldtree, current, o);
1762 * Bind merge.
1764 * Keep the index entries at stage0, collapse stage1 but make sure
1765 * stage0 does not have anything there.
1767 int bind_merge(struct cache_entry **src,
1768 struct unpack_trees_options *o)
1770 struct cache_entry *old = src[0];
1771 struct cache_entry *a = src[1];
1773 if (o->merge_size != 1)
1774 return error("Cannot do a bind merge of %d trees\n",
1775 o->merge_size);
1776 if (a && old)
1777 return o->gently ? -1 :
1778 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
1779 if (!a)
1780 return keep_entry(old, o);
1781 else
1782 return merged_entry(a, NULL, o);
1786 * One-way merge.
1788 * The rule is:
1789 * - take the stat information from stage0, take the data from stage1
1791 int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
1793 struct cache_entry *old = src[0];
1794 struct cache_entry *a = src[1];
1796 if (o->merge_size != 1)
1797 return error("Cannot do a oneway merge of %d trees",
1798 o->merge_size);
1800 if (!a || a == o->df_conflict_entry)
1801 return deleted_entry(old, old, o);
1803 if (old && same(old, a)) {
1804 int update = 0;
1805 if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
1806 struct stat st;
1807 if (lstat(old->name, &st) ||
1808 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
1809 update |= CE_UPDATE;
1811 add_entry(o, old, update, 0);
1812 return 0;
1814 return merged_entry(a, old, o);