Merge branch 'cs/pretty-formats-doc-typofix'
[git/git.git] / unpack-trees.c
1 #include "cache.h"
2 #include "argv-array.h"
3 #include "repository.h"
4 #include "config.h"
5 #include "dir.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "cache-tree.h"
9 #include "unpack-trees.h"
10 #include "progress.h"
11 #include "refs.h"
12 #include "attr.h"
13 #include "split-index.h"
14 #include "dir.h"
15 #include "submodule.h"
16 #include "submodule-config.h"
17 #include "fsmonitor.h"
18 #include "object-store.h"
19 #include "promisor-remote.h"
20
21 /*
22 * Error messages expected by scripts out of plumbing commands such as
23 * read-tree. Non-scripted Porcelain is not required to use these messages
24 * and in fact are encouraged to reword them to better suit their particular
25 * situation better. See how "git checkout" and "git merge" replaces
26 * them using setup_unpack_trees_porcelain(), for example.
27 */
28 static const char *unpack_plumbing_errors[NB_UNPACK_TREES_ERROR_TYPES] = {
29 /* ERROR_WOULD_OVERWRITE */
30 "Entry '%s' would be overwritten by merge. Cannot merge.",
31
32 /* ERROR_NOT_UPTODATE_FILE */
33 "Entry '%s' not uptodate. Cannot merge.",
34
35 /* ERROR_NOT_UPTODATE_DIR */
36 "Updating '%s' would lose untracked files in it",
37
38 /* ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN */
39 "Untracked working tree file '%s' would be overwritten by merge.",
40
41 /* ERROR_WOULD_LOSE_UNTRACKED_REMOVED */
42 "Untracked working tree file '%s' would be removed by merge.",
43
44 /* ERROR_BIND_OVERLAP */
45 "Entry '%s' overlaps with '%s'. Cannot bind.",
46
47 /* ERROR_SPARSE_NOT_UPTODATE_FILE */
48 "Entry '%s' not uptodate. Cannot update sparse checkout.",
49
50 /* ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN */
51 "Working tree file '%s' would be overwritten by sparse checkout update.",
52
53 /* ERROR_WOULD_LOSE_ORPHANED_REMOVED */
54 "Working tree file '%s' would be removed by sparse checkout update.",
55
56 /* ERROR_WOULD_LOSE_SUBMODULE */
57 "Submodule '%s' cannot checkout new HEAD.",
58 };
59
60 #define ERRORMSG(o,type) \
61 ( ((o) && (o)->msgs[(type)]) \
62 ? ((o)->msgs[(type)]) \
63 : (unpack_plumbing_errors[(type)]) )
64
65 static const char *super_prefixed(const char *path)
66 {
67 /*
68 * It is necessary and sufficient to have two static buffers
69 * here, as the return value of this function is fed to
70 * error() using the unpack_*_errors[] templates we see above.
71 */
72 static struct strbuf buf[2] = {STRBUF_INIT, STRBUF_INIT};
73 static int super_prefix_len = -1;
74 static unsigned idx = ARRAY_SIZE(buf) - 1;
75
76 if (super_prefix_len < 0) {
77 const char *super_prefix = get_super_prefix();
78 if (!super_prefix) {
79 super_prefix_len = 0;
80 } else {
81 int i;
82 for (i = 0; i < ARRAY_SIZE(buf); i++)
83 strbuf_addstr(&buf[i], super_prefix);
84 super_prefix_len = buf[0].len;
85 }
86 }
87
88 if (!super_prefix_len)
89 return path;
90
91 if (++idx >= ARRAY_SIZE(buf))
92 idx = 0;
93
94 strbuf_setlen(&buf[idx], super_prefix_len);
95 strbuf_addstr(&buf[idx], path);
96
97 return buf[idx].buf;
98 }
99
100 void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
101 const char *cmd)
102 {
103 int i;
104 const char **msgs = opts->msgs;
105 const char *msg;
106
107 argv_array_init(&opts->msgs_to_free);
108
109 if (!strcmp(cmd, "checkout"))
110 msg = advice_commit_before_merge
111 ? _("Your local changes to the following files would be overwritten by checkout:\n%%s"
112 "Please commit your changes or stash them before you switch branches.")
113 : _("Your local changes to the following files would be overwritten by checkout:\n%%s");
114 else if (!strcmp(cmd, "merge"))
115 msg = advice_commit_before_merge
116 ? _("Your local changes to the following files would be overwritten by merge:\n%%s"
117 "Please commit your changes or stash them before you merge.")
118 : _("Your local changes to the following files would be overwritten by merge:\n%%s");
119 else
120 msg = advice_commit_before_merge
121 ? _("Your local changes to the following files would be overwritten by %s:\n%%s"
122 "Please commit your changes or stash them before you %s.")
123 : _("Your local changes to the following files would be overwritten by %s:\n%%s");
124 msgs[ERROR_WOULD_OVERWRITE] = msgs[ERROR_NOT_UPTODATE_FILE] =
125 argv_array_pushf(&opts->msgs_to_free, msg, cmd, cmd);
126
127 msgs[ERROR_NOT_UPTODATE_DIR] =
128 _("Updating the following directories would lose untracked files in them:\n%s");
129
130 if (!strcmp(cmd, "checkout"))
131 msg = advice_commit_before_merge
132 ? _("The following untracked working tree files would be removed by checkout:\n%%s"
133 "Please move or remove them before you switch branches.")
134 : _("The following untracked working tree files would be removed by checkout:\n%%s");
135 else if (!strcmp(cmd, "merge"))
136 msg = advice_commit_before_merge
137 ? _("The following untracked working tree files would be removed by merge:\n%%s"
138 "Please move or remove them before you merge.")
139 : _("The following untracked working tree files would be removed by merge:\n%%s");
140 else
141 msg = advice_commit_before_merge
142 ? _("The following untracked working tree files would be removed by %s:\n%%s"
143 "Please move or remove them before you %s.")
144 : _("The following untracked working tree files would be removed by %s:\n%%s");
145 msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] =
146 argv_array_pushf(&opts->msgs_to_free, msg, cmd, cmd);
147
148 if (!strcmp(cmd, "checkout"))
149 msg = advice_commit_before_merge
150 ? _("The following untracked working tree files would be overwritten by checkout:\n%%s"
151 "Please move or remove them before you switch branches.")
152 : _("The following untracked working tree files would be overwritten by checkout:\n%%s");
153 else if (!strcmp(cmd, "merge"))
154 msg = advice_commit_before_merge
155 ? _("The following untracked working tree files would be overwritten by merge:\n%%s"
156 "Please move or remove them before you merge.")
157 : _("The following untracked working tree files would be overwritten by merge:\n%%s");
158 else
159 msg = advice_commit_before_merge
160 ? _("The following untracked working tree files would be overwritten by %s:\n%%s"
161 "Please move or remove them before you %s.")
162 : _("The following untracked working tree files would be overwritten by %s:\n%%s");
163 msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] =
164 argv_array_pushf(&opts->msgs_to_free, msg, cmd, cmd);
165
166 /*
167 * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
168 * cannot easily display it as a list.
169 */
170 msgs[ERROR_BIND_OVERLAP] = _("Entry '%s' overlaps with '%s'. Cannot bind.");
171
172 msgs[ERROR_SPARSE_NOT_UPTODATE_FILE] =
173 _("Cannot update sparse checkout: the following entries are not up to date:\n%s");
174 msgs[ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN] =
175 _("The following working tree files would be overwritten by sparse checkout update:\n%s");
176 msgs[ERROR_WOULD_LOSE_ORPHANED_REMOVED] =
177 _("The following working tree files would be removed by sparse checkout update:\n%s");
178 msgs[ERROR_WOULD_LOSE_SUBMODULE] =
179 _("Cannot update submodule:\n%s");
180
181 opts->show_all_errors = 1;
182 /* rejected paths may not have a static buffer */
183 for (i = 0; i < ARRAY_SIZE(opts->unpack_rejects); i++)
184 opts->unpack_rejects[i].strdup_strings = 1;
185 }
186
187 void clear_unpack_trees_porcelain(struct unpack_trees_options *opts)
188 {
189 argv_array_clear(&opts->msgs_to_free);
190 memset(opts->msgs, 0, sizeof(opts->msgs));
191 }
192
193 static int do_add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
194 unsigned int set, unsigned int clear)
195 {
196 clear |= CE_HASHED;
197
198 if (set & CE_REMOVE)
199 set |= CE_WT_REMOVE;
200
201 ce->ce_flags = (ce->ce_flags & ~clear) | set;
202 return add_index_entry(&o->result, ce,
203 ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
204 }
205
206 static void add_entry(struct unpack_trees_options *o,
207 const struct cache_entry *ce,
208 unsigned int set, unsigned int clear)
209 {
210 do_add_entry(o, dup_cache_entry(ce, &o->result), set, clear);
211 }
212
213 /*
214 * add error messages on path <path>
215 * corresponding to the type <e> with the message <msg>
216 * indicating if it should be display in porcelain or not
217 */
218 static int add_rejected_path(struct unpack_trees_options *o,
219 enum unpack_trees_error_types e,
220 const char *path)
221 {
222 if (o->quiet)
223 return -1;
224
225 if (!o->show_all_errors)
226 return error(ERRORMSG(o, e), super_prefixed(path));
227
228 /*
229 * Otherwise, insert in a list for future display by
230 * display_error_msgs()
231 */
232 string_list_append(&o->unpack_rejects[e], path);
233 return -1;
234 }
235
236 /*
237 * display all the error messages stored in a nice way
238 */
239 static void display_error_msgs(struct unpack_trees_options *o)
240 {
241 int e, i;
242 int something_displayed = 0;
243 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
244 struct string_list *rejects = &o->unpack_rejects[e];
245 if (rejects->nr > 0) {
246 struct strbuf path = STRBUF_INIT;
247 something_displayed = 1;
248 for (i = 0; i < rejects->nr; i++)
249 strbuf_addf(&path, "\t%s\n", rejects->items[i].string);
250 error(ERRORMSG(o, e), super_prefixed(path.buf));
251 strbuf_release(&path);
252 }
253 string_list_clear(rejects, 0);
254 }
255 if (something_displayed)
256 fprintf(stderr, _("Aborting\n"));
257 }
258
259 static int check_submodule_move_head(const struct cache_entry *ce,
260 const char *old_id,
261 const char *new_id,
262 struct unpack_trees_options *o)
263 {
264 unsigned flags = SUBMODULE_MOVE_HEAD_DRY_RUN;
265 const struct submodule *sub = submodule_from_ce(ce);
266
267 if (!sub)
268 return 0;
269
270 if (o->reset)
271 flags |= SUBMODULE_MOVE_HEAD_FORCE;
272
273 if (submodule_move_head(ce->name, old_id, new_id, flags))
274 return add_rejected_path(o, ERROR_WOULD_LOSE_SUBMODULE, ce->name);
275 return 0;
276 }
277
278 /*
279 * Preform the loading of the repository's gitmodules file. This function is
280 * used by 'check_update()' to perform loading of the gitmodules file in two
281 * differnt situations:
282 * (1) before removing entries from the working tree if the gitmodules file has
283 * been marked for removal. This situation is specified by 'state' == NULL.
284 * (2) before checking out entries to the working tree if the gitmodules file
285 * has been marked for update. This situation is specified by 'state' != NULL.
286 */
287 static void load_gitmodules_file(struct index_state *index,
288 struct checkout *state)
289 {
290 int pos = index_name_pos(index, GITMODULES_FILE, strlen(GITMODULES_FILE));
291
292 if (pos >= 0) {
293 struct cache_entry *ce = index->cache[pos];
294 if (!state && ce->ce_flags & CE_WT_REMOVE) {
295 repo_read_gitmodules(the_repository);
296 } else if (state && (ce->ce_flags & CE_UPDATE)) {
297 submodule_free(the_repository);
298 checkout_entry(ce, state, NULL, NULL);
299 repo_read_gitmodules(the_repository);
300 }
301 }
302 }
303
304 static struct progress *get_progress(struct unpack_trees_options *o)
305 {
306 unsigned cnt = 0, total = 0;
307 struct index_state *index = &o->result;
308
309 if (!o->update || !o->verbose_update)
310 return NULL;
311
312 for (; cnt < index->cache_nr; cnt++) {
313 const struct cache_entry *ce = index->cache[cnt];
314 if (ce->ce_flags & (CE_UPDATE | CE_WT_REMOVE))
315 total++;
316 }
317
318 return start_delayed_progress(_("Updating files"), total);
319 }
320
321 static void setup_collided_checkout_detection(struct checkout *state,
322 struct index_state *index)
323 {
324 int i;
325
326 state->clone = 1;
327 for (i = 0; i < index->cache_nr; i++)
328 index->cache[i]->ce_flags &= ~CE_MATCHED;
329 }
330
331 static void report_collided_checkout(struct index_state *index)
332 {
333 struct string_list list = STRING_LIST_INIT_NODUP;
334 int i;
335
336 for (i = 0; i < index->cache_nr; i++) {
337 struct cache_entry *ce = index->cache[i];
338
339 if (!(ce->ce_flags & CE_MATCHED))
340 continue;
341
342 string_list_append(&list, ce->name);
343 ce->ce_flags &= ~CE_MATCHED;
344 }
345
346 list.cmp = fspathcmp;
347 string_list_sort(&list);
348
349 if (list.nr) {
350 warning(_("the following paths have collided (e.g. case-sensitive paths\n"
351 "on a case-insensitive filesystem) and only one from the same\n"
352 "colliding group is in the working tree:\n"));
353
354 for (i = 0; i < list.nr; i++)
355 fprintf(stderr, " '%s'\n", list.items[i].string);
356 }
357
358 string_list_clear(&list, 0);
359 }
360
361 static int check_updates(struct unpack_trees_options *o)
362 {
363 unsigned cnt = 0;
364 int errs = 0;
365 struct progress *progress;
366 struct index_state *index = &o->result;
367 struct checkout state = CHECKOUT_INIT;
368 int i;
369
370 trace_performance_enter();
371 state.force = 1;
372 state.quiet = 1;
373 state.refresh_cache = 1;
374 state.istate = index;
375
376 if (o->clone)
377 setup_collided_checkout_detection(&state, index);
378
379 progress = get_progress(o);
380
381 if (o->update)
382 git_attr_set_direction(GIT_ATTR_CHECKOUT);
383
384 if (should_update_submodules() && o->update && !o->dry_run)
385 load_gitmodules_file(index, NULL);
386
387 for (i = 0; i < index->cache_nr; i++) {
388 const struct cache_entry *ce = index->cache[i];
389
390 if (ce->ce_flags & CE_WT_REMOVE) {
391 display_progress(progress, ++cnt);
392 if (o->update && !o->dry_run)
393 unlink_entry(ce);
394 }
395 }
396 remove_marked_cache_entries(index, 0);
397 remove_scheduled_dirs();
398
399 if (should_update_submodules() && o->update && !o->dry_run)
400 load_gitmodules_file(index, &state);
401
402 enable_delayed_checkout(&state);
403 if (has_promisor_remote() && o->update && !o->dry_run) {
404 /*
405 * Prefetch the objects that are to be checked out in the loop
406 * below.
407 */
408 struct oid_array to_fetch = OID_ARRAY_INIT;
409 for (i = 0; i < index->cache_nr; i++) {
410 struct cache_entry *ce = index->cache[i];
411
412 if (!(ce->ce_flags & CE_UPDATE) ||
413 S_ISGITLINK(ce->ce_mode))
414 continue;
415 if (!oid_object_info_extended(the_repository, &ce->oid,
416 NULL,
417 OBJECT_INFO_FOR_PREFETCH))
418 continue;
419 oid_array_append(&to_fetch, &ce->oid);
420 }
421 if (to_fetch.nr)
422 promisor_remote_get_direct(the_repository,
423 to_fetch.oid, to_fetch.nr);
424 oid_array_clear(&to_fetch);
425 }
426 for (i = 0; i < index->cache_nr; i++) {
427 struct cache_entry *ce = index->cache[i];
428
429 if (ce->ce_flags & CE_UPDATE) {
430 if (ce->ce_flags & CE_WT_REMOVE)
431 BUG("both update and delete flags are set on %s",
432 ce->name);
433 display_progress(progress, ++cnt);
434 ce->ce_flags &= ~CE_UPDATE;
435 if (o->update && !o->dry_run) {
436 errs |= checkout_entry(ce, &state, NULL, NULL);
437 }
438 }
439 }
440 stop_progress(&progress);
441 errs |= finish_delayed_checkout(&state, NULL);
442 if (o->update)
443 git_attr_set_direction(GIT_ATTR_CHECKIN);
444
445 if (o->clone)
446 report_collided_checkout(index);
447
448 trace_performance_leave("check_updates");
449 return errs != 0;
450 }
451
452 static int verify_uptodate_sparse(const struct cache_entry *ce,
453 struct unpack_trees_options *o);
454 static int verify_absent_sparse(const struct cache_entry *ce,
455 enum unpack_trees_error_types,
456 struct unpack_trees_options *o);
457
458 static int apply_sparse_checkout(struct index_state *istate,
459 struct cache_entry *ce,
460 struct unpack_trees_options *o)
461 {
462 int was_skip_worktree = ce_skip_worktree(ce);
463
464 if (ce->ce_flags & CE_NEW_SKIP_WORKTREE)
465 ce->ce_flags |= CE_SKIP_WORKTREE;
466 else
467 ce->ce_flags &= ~CE_SKIP_WORKTREE;
468 if (was_skip_worktree != ce_skip_worktree(ce)) {
469 ce->ce_flags |= CE_UPDATE_IN_BASE;
470 mark_fsmonitor_invalid(istate, ce);
471 istate->cache_changed |= CE_ENTRY_CHANGED;
472 }
473
474 /*
475 * if (!was_skip_worktree && !ce_skip_worktree()) {
476 * This is perfectly normal. Move on;
477 * }
478 */
479
480 /*
481 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
482 * area as a result of ce_skip_worktree() shortcuts in
483 * verify_absent() and verify_uptodate().
484 * Make sure they don't modify worktree if they are already
485 * outside checkout area
486 */
487 if (was_skip_worktree && ce_skip_worktree(ce)) {
488 ce->ce_flags &= ~CE_UPDATE;
489
490 /*
491 * By default, when CE_REMOVE is on, CE_WT_REMOVE is also
492 * on to get that file removed from both index and worktree.
493 * If that file is already outside worktree area, don't
494 * bother remove it.
495 */
496 if (ce->ce_flags & CE_REMOVE)
497 ce->ce_flags &= ~CE_WT_REMOVE;
498 }
499
500 if (!was_skip_worktree && ce_skip_worktree(ce)) {
501 /*
502 * If CE_UPDATE is set, verify_uptodate() must be called already
503 * also stat info may have lost after merged_entry() so calling
504 * verify_uptodate() again may fail
505 */
506 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
507 return -1;
508 ce->ce_flags |= CE_WT_REMOVE;
509 ce->ce_flags &= ~CE_UPDATE;
510 }
511 if (was_skip_worktree && !ce_skip_worktree(ce)) {
512 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
513 return -1;
514 ce->ce_flags |= CE_UPDATE;
515 }
516 return 0;
517 }
518
519 static inline int call_unpack_fn(const struct cache_entry * const *src,
520 struct unpack_trees_options *o)
521 {
522 int ret = o->fn(src, o);
523 if (ret > 0)
524 ret = 0;
525 return ret;
526 }
527
528 static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
529 {
530 ce->ce_flags |= CE_UNPACKED;
531
532 if (o->cache_bottom < o->src_index->cache_nr &&
533 o->src_index->cache[o->cache_bottom] == ce) {
534 int bottom = o->cache_bottom;
535 while (bottom < o->src_index->cache_nr &&
536 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
537 bottom++;
538 o->cache_bottom = bottom;
539 }
540 }
541
542 static void mark_all_ce_unused(struct index_state *index)
543 {
544 int i;
545 for (i = 0; i < index->cache_nr; i++)
546 index->cache[i]->ce_flags &= ~(CE_UNPACKED | CE_ADDED | CE_NEW_SKIP_WORKTREE);
547 }
548
549 static int locate_in_src_index(const struct cache_entry *ce,
550 struct unpack_trees_options *o)
551 {
552 struct index_state *index = o->src_index;
553 int len = ce_namelen(ce);
554 int pos = index_name_pos(index, ce->name, len);
555 if (pos < 0)
556 pos = -1 - pos;
557 return pos;
558 }
559
560 /*
561 * We call unpack_index_entry() with an unmerged cache entry
562 * only in diff-index, and it wants a single callback. Skip
563 * the other unmerged entry with the same name.
564 */
565 static void mark_ce_used_same_name(struct cache_entry *ce,
566 struct unpack_trees_options *o)
567 {
568 struct index_state *index = o->src_index;
569 int len = ce_namelen(ce);
570 int pos;
571
572 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
573 struct cache_entry *next = index->cache[pos];
574 if (len != ce_namelen(next) ||
575 memcmp(ce->name, next->name, len))
576 break;
577 mark_ce_used(next, o);
578 }
579 }
580
581 static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
582 {
583 const struct index_state *index = o->src_index;
584 int pos = o->cache_bottom;
585
586 while (pos < index->cache_nr) {
587 struct cache_entry *ce = index->cache[pos];
588 if (!(ce->ce_flags & CE_UNPACKED))
589 return ce;
590 pos++;
591 }
592 return NULL;
593 }
594
595 static void add_same_unmerged(const struct cache_entry *ce,
596 struct unpack_trees_options *o)
597 {
598 struct index_state *index = o->src_index;
599 int len = ce_namelen(ce);
600 int pos = index_name_pos(index, ce->name, len);
601
602 if (0 <= pos)
603 die("programming error in a caller of mark_ce_used_same_name");
604 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
605 struct cache_entry *next = index->cache[pos];
606 if (len != ce_namelen(next) ||
607 memcmp(ce->name, next->name, len))
608 break;
609 add_entry(o, next, 0, 0);
610 mark_ce_used(next, o);
611 }
612 }
613
614 static int unpack_index_entry(struct cache_entry *ce,
615 struct unpack_trees_options *o)
616 {
617 const struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
618 int ret;
619
620 src[0] = ce;
621
622 mark_ce_used(ce, o);
623 if (ce_stage(ce)) {
624 if (o->skip_unmerged) {
625 add_entry(o, ce, 0, 0);
626 return 0;
627 }
628 }
629 ret = call_unpack_fn(src, o);
630 if (ce_stage(ce))
631 mark_ce_used_same_name(ce, o);
632 return ret;
633 }
634
635 static int find_cache_pos(struct traverse_info *, const char *p, size_t len);
636
637 static void restore_cache_bottom(struct traverse_info *info, int bottom)
638 {
639 struct unpack_trees_options *o = info->data;
640
641 if (o->diff_index_cached)
642 return;
643 o->cache_bottom = bottom;
644 }
645
646 static int switch_cache_bottom(struct traverse_info *info)
647 {
648 struct unpack_trees_options *o = info->data;
649 int ret, pos;
650
651 if (o->diff_index_cached)
652 return 0;
653 ret = o->cache_bottom;
654 pos = find_cache_pos(info->prev, info->name, info->namelen);
655
656 if (pos < -1)
657 o->cache_bottom = -2 - pos;
658 else if (pos < 0)
659 o->cache_bottom = o->src_index->cache_nr;
660 return ret;
661 }
662
663 static inline int are_same_oid(struct name_entry *name_j, struct name_entry *name_k)
664 {
665 return !is_null_oid(&name_j->oid) && !is_null_oid(&name_k->oid) && oideq(&name_j->oid, &name_k->oid);
666 }
667
668 static int all_trees_same_as_cache_tree(int n, unsigned long dirmask,
669 struct name_entry *names,
670 struct traverse_info *info)
671 {
672 struct unpack_trees_options *o = info->data;
673 int i;
674
675 if (!o->merge || dirmask != ((1 << n) - 1))
676 return 0;
677
678 for (i = 1; i < n; i++)
679 if (!are_same_oid(names, names + i))
680 return 0;
681
682 return cache_tree_matches_traversal(o->src_index->cache_tree, names, info);
683 }
684
685 static int index_pos_by_traverse_info(struct name_entry *names,
686 struct traverse_info *info)
687 {
688 struct unpack_trees_options *o = info->data;
689 struct strbuf name = STRBUF_INIT;
690 int pos;
691
692 strbuf_make_traverse_path(&name, info, names->path, names->pathlen);
693 strbuf_addch(&name, '/');
694 pos = index_name_pos(o->src_index, name.buf, name.len);
695 if (pos >= 0)
696 BUG("This is a directory and should not exist in index");
697 pos = -pos - 1;
698 if (!starts_with(o->src_index->cache[pos]->name, name.buf) ||
699 (pos > 0 && starts_with(o->src_index->cache[pos-1]->name, name.buf)))
700 BUG("pos must point at the first entry in this directory");
701 strbuf_release(&name);
702 return pos;
703 }
704
705 /*
706 * Fast path if we detect that all trees are the same as cache-tree at this
707 * path. We'll walk these trees in an iterative loop using cache-tree/index
708 * instead of ODB since we already know what these trees contain.
709 */
710 static int traverse_by_cache_tree(int pos, int nr_entries, int nr_names,
711 struct traverse_info *info)
712 {
713 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
714 struct unpack_trees_options *o = info->data;
715 struct cache_entry *tree_ce = NULL;
716 int ce_len = 0;
717 int i, d;
718
719 if (!o->merge)
720 BUG("We need cache-tree to do this optimization");
721
722 /*
723 * Do what unpack_callback() and unpack_nondirectories() normally
724 * do. But we walk all paths in an iterative loop instead.
725 *
726 * D/F conflicts and higher stage entries are not a concern
727 * because cache-tree would be invalidated and we would never
728 * get here in the first place.
729 */
730 for (i = 0; i < nr_entries; i++) {
731 int new_ce_len, len, rc;
732
733 src[0] = o->src_index->cache[pos + i];
734
735 len = ce_namelen(src[0]);
736 new_ce_len = cache_entry_size(len);
737
738 if (new_ce_len > ce_len) {
739 new_ce_len <<= 1;
740 tree_ce = xrealloc(tree_ce, new_ce_len);
741 memset(tree_ce, 0, new_ce_len);
742 ce_len = new_ce_len;
743
744 tree_ce->ce_flags = create_ce_flags(0);
745
746 for (d = 1; d <= nr_names; d++)
747 src[d] = tree_ce;
748 }
749
750 tree_ce->ce_mode = src[0]->ce_mode;
751 tree_ce->ce_namelen = len;
752 oidcpy(&tree_ce->oid, &src[0]->oid);
753 memcpy(tree_ce->name, src[0]->name, len + 1);
754
755 rc = call_unpack_fn((const struct cache_entry * const *)src, o);
756 if (rc < 0) {
757 free(tree_ce);
758 return rc;
759 }
760
761 mark_ce_used(src[0], o);
762 }
763 free(tree_ce);
764 if (o->debug_unpack)
765 printf("Unpacked %d entries from %s to %s using cache-tree\n",
766 nr_entries,
767 o->src_index->cache[pos]->name,
768 o->src_index->cache[pos + nr_entries - 1]->name);
769 return 0;
770 }
771
772 static int traverse_trees_recursive(int n, unsigned long dirmask,
773 unsigned long df_conflicts,
774 struct name_entry *names,
775 struct traverse_info *info)
776 {
777 struct unpack_trees_options *o = info->data;
778 int i, ret, bottom;
779 int nr_buf = 0;
780 struct tree_desc t[MAX_UNPACK_TREES];
781 void *buf[MAX_UNPACK_TREES];
782 struct traverse_info newinfo;
783 struct name_entry *p;
784 int nr_entries;
785
786 nr_entries = all_trees_same_as_cache_tree(n, dirmask, names, info);
787 if (nr_entries > 0) {
788 int pos = index_pos_by_traverse_info(names, info);
789
790 if (!o->merge || df_conflicts)
791 BUG("Wrong condition to get here buddy");
792
793 /*
794 * All entries up to 'pos' must have been processed
795 * (i.e. marked CE_UNPACKED) at this point. But to be safe,
796 * save and restore cache_bottom anyway to not miss
797 * unprocessed entries before 'pos'.
798 */
799 bottom = o->cache_bottom;
800 ret = traverse_by_cache_tree(pos, nr_entries, n, info);
801 o->cache_bottom = bottom;
802 return ret;
803 }
804
805 p = names;
806 while (!p->mode)
807 p++;
808
809 newinfo = *info;
810 newinfo.prev = info;
811 newinfo.pathspec = info->pathspec;
812 newinfo.name = p->path;
813 newinfo.namelen = p->pathlen;
814 newinfo.mode = p->mode;
815 newinfo.pathlen = st_add3(newinfo.pathlen, tree_entry_len(p), 1);
816 newinfo.df_conflicts |= df_conflicts;
817
818 /*
819 * Fetch the tree from the ODB for each peer directory in the
820 * n commits.
821 *
822 * For 2- and 3-way traversals, we try to avoid hitting the
823 * ODB twice for the same OID. This should yield a nice speed
824 * up in checkouts and merges when the commits are similar.
825 *
826 * We don't bother doing the full O(n^2) search for larger n,
827 * because wider traversals don't happen that often and we
828 * avoid the search setup.
829 *
830 * When 2 peer OIDs are the same, we just copy the tree
831 * descriptor data. This implicitly borrows the buffer
832 * data from the earlier cell.
833 */
834 for (i = 0; i < n; i++, dirmask >>= 1) {
835 if (i > 0 && are_same_oid(&names[i], &names[i - 1]))
836 t[i] = t[i - 1];
837 else if (i > 1 && are_same_oid(&names[i], &names[i - 2]))
838 t[i] = t[i - 2];
839 else {
840 const struct object_id *oid = NULL;
841 if (dirmask & 1)
842 oid = &names[i].oid;
843 buf[nr_buf++] = fill_tree_descriptor(the_repository, t + i, oid);
844 }
845 }
846
847 bottom = switch_cache_bottom(&newinfo);
848 ret = traverse_trees(o->src_index, n, t, &newinfo);
849 restore_cache_bottom(&newinfo, bottom);
850
851 for (i = 0; i < nr_buf; i++)
852 free(buf[i]);
853
854 return ret;
855 }
856
857 /*
858 * Compare the traverse-path to the cache entry without actually
859 * having to generate the textual representation of the traverse
860 * path.
861 *
862 * NOTE! This *only* compares up to the size of the traverse path
863 * itself - the caller needs to do the final check for the cache
864 * entry having more data at the end!
865 */
866 static int do_compare_entry_piecewise(const struct cache_entry *ce,
867 const struct traverse_info *info,
868 const char *name, size_t namelen,
869 unsigned mode)
870 {
871 int pathlen, ce_len;
872 const char *ce_name;
873
874 if (info->prev) {
875 int cmp = do_compare_entry_piecewise(ce, info->prev,
876 info->name, info->namelen,
877 info->mode);
878 if (cmp)
879 return cmp;
880 }
881 pathlen = info->pathlen;
882 ce_len = ce_namelen(ce);
883
884 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
885 if (ce_len < pathlen)
886 return -1;
887
888 ce_len -= pathlen;
889 ce_name = ce->name + pathlen;
890
891 return df_name_compare(ce_name, ce_len, S_IFREG, name, namelen, mode);
892 }
893
894 static int do_compare_entry(const struct cache_entry *ce,
895 const struct traverse_info *info,
896 const char *name, size_t namelen,
897 unsigned mode)
898 {
899 int pathlen, ce_len;
900 const char *ce_name;
901 int cmp;
902
903 /*
904 * If we have not precomputed the traverse path, it is quicker
905 * to avoid doing so. But if we have precomputed it,
906 * it is quicker to use the precomputed version.
907 */
908 if (!info->traverse_path)
909 return do_compare_entry_piecewise(ce, info, name, namelen, mode);
910
911 cmp = strncmp(ce->name, info->traverse_path, info->pathlen);
912 if (cmp)
913 return cmp;
914
915 pathlen = info->pathlen;
916 ce_len = ce_namelen(ce);
917
918 if (ce_len < pathlen)
919 return -1;
920
921 ce_len -= pathlen;
922 ce_name = ce->name + pathlen;
923
924 return df_name_compare(ce_name, ce_len, S_IFREG, name, namelen, mode);
925 }
926
927 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
928 {
929 int cmp = do_compare_entry(ce, info, n->path, n->pathlen, n->mode);
930 if (cmp)
931 return cmp;
932
933 /*
934 * Even if the beginning compared identically, the ce should
935 * compare as bigger than a directory leading up to it!
936 */
937 return ce_namelen(ce) > traverse_path_len(info, tree_entry_len(n));
938 }
939
940 static int ce_in_traverse_path(const struct cache_entry *ce,
941 const struct traverse_info *info)
942 {
943 if (!info->prev)
944 return 1;
945 if (do_compare_entry(ce, info->prev,
946 info->name, info->namelen, info->mode))
947 return 0;
948 /*
949 * If ce (blob) is the same name as the path (which is a tree
950 * we will be descending into), it won't be inside it.
951 */
952 return (info->pathlen < ce_namelen(ce));
953 }
954
955 static struct cache_entry *create_ce_entry(const struct traverse_info *info,
956 const struct name_entry *n,
957 int stage,
958 struct index_state *istate,
959 int is_transient)
960 {
961 size_t len = traverse_path_len(info, tree_entry_len(n));
962 struct cache_entry *ce =
963 is_transient ?
964 make_empty_transient_cache_entry(len) :
965 make_empty_cache_entry(istate, len);
966
967 ce->ce_mode = create_ce_mode(n->mode);
968 ce->ce_flags = create_ce_flags(stage);
969 ce->ce_namelen = len;
970 oidcpy(&ce->oid, &n->oid);
971 /* len+1 because the cache_entry allocates space for NUL */
972 make_traverse_path(ce->name, len + 1, info, n->path, n->pathlen);
973
974 return ce;
975 }
976
977 /*
978 * Note that traverse_by_cache_tree() duplicates some logic in this function
979 * without actually calling it. If you change the logic here you may need to
980 * check and change there as well.
981 */
982 static int unpack_nondirectories(int n, unsigned long mask,
983 unsigned long dirmask,
984 struct cache_entry **src,
985 const struct name_entry *names,
986 const struct traverse_info *info)
987 {
988 int i;
989 struct unpack_trees_options *o = info->data;
990 unsigned long conflicts = info->df_conflicts | dirmask;
991
992 /* Do we have *only* directories? Nothing to do */
993 if (mask == dirmask && !src[0])
994 return 0;
995
996 /*
997 * Ok, we've filled in up to any potential index entry in src[0],
998 * now do the rest.
999 */
1000 for (i = 0; i < n; i++) {
1001 int stage;
1002 unsigned int bit = 1ul << i;
1003 if (conflicts & bit) {
1004 src[i + o->merge] = o->df_conflict_entry;
1005 continue;
1006 }
1007 if (!(mask & bit))
1008 continue;
1009 if (!o->merge)
1010 stage = 0;
1011 else if (i + 1 < o->head_idx)
1012 stage = 1;
1013 else if (i + 1 > o->head_idx)
1014 stage = 3;
1015 else
1016 stage = 2;
1017
1018 /*
1019 * If the merge bit is set, then the cache entries are
1020 * discarded in the following block. In this case,
1021 * construct "transient" cache_entries, as they are
1022 * not stored in the index. otherwise construct the
1023 * cache entry from the index aware logic.
1024 */
1025 src[i + o->merge] = create_ce_entry(info, names + i, stage, &o->result, o->merge);
1026 }
1027
1028 if (o->merge) {
1029 int rc = call_unpack_fn((const struct cache_entry * const *)src,
1030 o);
1031 for (i = 0; i < n; i++) {
1032 struct cache_entry *ce = src[i + o->merge];
1033 if (ce != o->df_conflict_entry)
1034 discard_cache_entry(ce);
1035 }
1036 return rc;
1037 }
1038
1039 for (i = 0; i < n; i++)
1040 if (src[i] && src[i] != o->df_conflict_entry)
1041 if (do_add_entry(o, src[i], 0, 0))
1042 return -1;
1043
1044 return 0;
1045 }
1046
1047 static int unpack_failed(struct unpack_trees_options *o, const char *message)
1048 {
1049 discard_index(&o->result);
1050 if (!o->quiet && !o->exiting_early) {
1051 if (message)
1052 return error("%s", message);
1053 return -1;
1054 }
1055 return -1;
1056 }
1057
1058 /*
1059 * The tree traversal is looking at name p. If we have a matching entry,
1060 * return it. If name p is a directory in the index, do not return
1061 * anything, as we will want to match it when the traversal descends into
1062 * the directory.
1063 */
1064 static int find_cache_pos(struct traverse_info *info,
1065 const char *p, size_t p_len)
1066 {
1067 int pos;
1068 struct unpack_trees_options *o = info->data;
1069 struct index_state *index = o->src_index;
1070 int pfxlen = info->pathlen;
1071
1072 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
1073 const struct cache_entry *ce = index->cache[pos];
1074 const char *ce_name, *ce_slash;
1075 int cmp, ce_len;
1076
1077 if (ce->ce_flags & CE_UNPACKED) {
1078 /*
1079 * cache_bottom entry is already unpacked, so
1080 * we can never match it; don't check it
1081 * again.
1082 */
1083 if (pos == o->cache_bottom)
1084 ++o->cache_bottom;
1085 continue;
1086 }
1087 if (!ce_in_traverse_path(ce, info)) {
1088 /*
1089 * Check if we can skip future cache checks
1090 * (because we're already past all possible
1091 * entries in the traverse path).
1092 */
1093 if (info->traverse_path) {
1094 if (strncmp(ce->name, info->traverse_path,
1095 info->pathlen) > 0)
1096 break;
1097 }
1098 continue;
1099 }
1100 ce_name = ce->name + pfxlen;
1101 ce_slash = strchr(ce_name, '/');
1102 if (ce_slash)
1103 ce_len = ce_slash - ce_name;
1104 else
1105 ce_len = ce_namelen(ce) - pfxlen;
1106 cmp = name_compare(p, p_len, ce_name, ce_len);
1107 /*
1108 * Exact match; if we have a directory we need to
1109 * delay returning it.
1110 */
1111 if (!cmp)
1112 return ce_slash ? -2 - pos : pos;
1113 if (0 < cmp)
1114 continue; /* keep looking */
1115 /*
1116 * ce_name sorts after p->path; could it be that we
1117 * have files under p->path directory in the index?
1118 * E.g. ce_name == "t-i", and p->path == "t"; we may
1119 * have "t/a" in the index.
1120 */
1121 if (p_len < ce_len && !memcmp(ce_name, p, p_len) &&
1122 ce_name[p_len] < '/')
1123 continue; /* keep looking */
1124 break;
1125 }
1126 return -1;
1127 }
1128
1129 static struct cache_entry *find_cache_entry(struct traverse_info *info,
1130 const struct name_entry *p)
1131 {
1132 int pos = find_cache_pos(info, p->path, p->pathlen);
1133 struct unpack_trees_options *o = info->data;
1134
1135 if (0 <= pos)
1136 return o->src_index->cache[pos];
1137 else
1138 return NULL;
1139 }
1140
1141 static void debug_path(struct traverse_info *info)
1142 {
1143 if (info->prev) {
1144 debug_path(info->prev);
1145 if (*info->prev->name)
1146 putchar('/');
1147 }
1148 printf("%s", info->name);
1149 }
1150
1151 static void debug_name_entry(int i, struct name_entry *n)
1152 {
1153 printf("ent#%d %06o %s\n", i,
1154 n->path ? n->mode : 0,
1155 n->path ? n->path : "(missing)");
1156 }
1157
1158 static void debug_unpack_callback(int n,
1159 unsigned long mask,
1160 unsigned long dirmask,
1161 struct name_entry *names,
1162 struct traverse_info *info)
1163 {
1164 int i;
1165 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
1166 mask, dirmask, n);
1167 debug_path(info);
1168 putchar('\n');
1169 for (i = 0; i < n; i++)
1170 debug_name_entry(i, names + i);
1171 }
1172
1173 /*
1174 * Note that traverse_by_cache_tree() duplicates some logic in this function
1175 * without actually calling it. If you change the logic here you may need to
1176 * check and change there as well.
1177 */
1178 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
1179 {
1180 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
1181 struct unpack_trees_options *o = info->data;
1182 const struct name_entry *p = names;
1183
1184 /* Find first entry with a real name (we could use "mask" too) */
1185 while (!p->mode)
1186 p++;
1187
1188 if (o->debug_unpack)
1189 debug_unpack_callback(n, mask, dirmask, names, info);
1190
1191 /* Are we supposed to look at the index too? */
1192 if (o->merge) {
1193 while (1) {
1194 int cmp;
1195 struct cache_entry *ce;
1196
1197 if (o->diff_index_cached)
1198 ce = next_cache_entry(o);
1199 else
1200 ce = find_cache_entry(info, p);
1201
1202 if (!ce)
1203 break;
1204 cmp = compare_entry(ce, info, p);
1205 if (cmp < 0) {
1206 if (unpack_index_entry(ce, o) < 0)
1207 return unpack_failed(o, NULL);
1208 continue;
1209 }
1210 if (!cmp) {
1211 if (ce_stage(ce)) {
1212 /*
1213 * If we skip unmerged index
1214 * entries, we'll skip this
1215 * entry *and* the tree
1216 * entries associated with it!
1217 */
1218 if (o->skip_unmerged) {
1219 add_same_unmerged(ce, o);
1220 return mask;
1221 }
1222 }
1223 src[0] = ce;
1224 }
1225 break;
1226 }
1227 }
1228
1229 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
1230 return -1;
1231
1232 if (o->merge && src[0]) {
1233 if (ce_stage(src[0]))
1234 mark_ce_used_same_name(src[0], o);
1235 else
1236 mark_ce_used(src[0], o);
1237 }
1238
1239 /* Now handle any directories.. */
1240 if (dirmask) {
1241 /* special case: "diff-index --cached" looking at a tree */
1242 if (o->diff_index_cached &&
1243 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
1244 int matches;
1245 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
1246 names, info);
1247 /*
1248 * Everything under the name matches; skip the
1249 * entire hierarchy. diff_index_cached codepath
1250 * special cases D/F conflicts in such a way that
1251 * it does not do any look-ahead, so this is safe.
1252 */
1253 if (matches) {
1254 o->cache_bottom += matches;
1255 return mask;
1256 }
1257 }
1258
1259 if (traverse_trees_recursive(n, dirmask, mask & ~dirmask,
1260 names, info) < 0)
1261 return -1;
1262 return mask;
1263 }
1264
1265 return mask;
1266 }
1267
1268 static int clear_ce_flags_1(struct index_state *istate,
1269 struct cache_entry **cache, int nr,
1270 struct strbuf *prefix,
1271 int select_mask, int clear_mask,
1272 struct pattern_list *pl,
1273 enum pattern_match_result default_match);
1274
1275 /* Whole directory matching */
1276 static int clear_ce_flags_dir(struct index_state *istate,
1277 struct cache_entry **cache, int nr,
1278 struct strbuf *prefix,
1279 char *basename,
1280 int select_mask, int clear_mask,
1281 struct pattern_list *pl,
1282 enum pattern_match_result default_match)
1283 {
1284 struct cache_entry **cache_end;
1285 int dtype = DT_DIR;
1286 int rc;
1287 enum pattern_match_result ret;
1288 ret = path_matches_pattern_list(prefix->buf, prefix->len,
1289 basename, &dtype, pl, istate);
1290
1291 strbuf_addch(prefix, '/');
1292
1293 /* If undecided, use matching result of parent dir in defval */
1294 if (ret == UNDECIDED)
1295 ret = default_match;
1296
1297 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
1298 struct cache_entry *ce = *cache_end;
1299 if (strncmp(ce->name, prefix->buf, prefix->len))
1300 break;
1301 }
1302
1303 /*
1304 * TODO: check pl, if there are no patterns that may conflict
1305 * with ret (iow, we know in advance the incl/excl
1306 * decision for the entire directory), clear flag here without
1307 * calling clear_ce_flags_1(). That function will call
1308 * the expensive path_matches_pattern_list() on every entry.
1309 */
1310 rc = clear_ce_flags_1(istate, cache, cache_end - cache,
1311 prefix,
1312 select_mask, clear_mask,
1313 pl, ret);
1314 strbuf_setlen(prefix, prefix->len - 1);
1315 return rc;
1316 }
1317
1318 /*
1319 * Traverse the index, find every entry that matches according to
1320 * o->pl. Do "ce_flags &= ~clear_mask" on those entries. Return the
1321 * number of traversed entries.
1322 *
1323 * If select_mask is non-zero, only entries whose ce_flags has on of
1324 * those bits enabled are traversed.
1325 *
1326 * cache : pointer to an index entry
1327 * prefix_len : an offset to its path
1328 *
1329 * The current path ("prefix") including the trailing '/' is
1330 * cache[0]->name[0..(prefix_len-1)]
1331 * Top level path has prefix_len zero.
1332 */
1333 static int clear_ce_flags_1(struct index_state *istate,
1334 struct cache_entry **cache, int nr,
1335 struct strbuf *prefix,
1336 int select_mask, int clear_mask,
1337 struct pattern_list *pl,
1338 enum pattern_match_result default_match)
1339 {
1340 struct cache_entry **cache_end = cache + nr;
1341
1342 /*
1343 * Process all entries that have the given prefix and meet
1344 * select_mask condition
1345 */
1346 while(cache != cache_end) {
1347 struct cache_entry *ce = *cache;
1348 const char *name, *slash;
1349 int len, dtype;
1350 enum pattern_match_result ret;
1351
1352 if (select_mask && !(ce->ce_flags & select_mask)) {
1353 cache++;
1354 continue;
1355 }
1356
1357 if (prefix->len && strncmp(ce->name, prefix->buf, prefix->len))
1358 break;
1359
1360 name = ce->name + prefix->len;
1361 slash = strchr(name, '/');
1362
1363 /* If it's a directory, try whole directory match first */
1364 if (slash) {
1365 int processed;
1366
1367 len = slash - name;
1368 strbuf_add(prefix, name, len);
1369
1370 processed = clear_ce_flags_dir(istate, cache, cache_end - cache,
1371 prefix,
1372 prefix->buf + prefix->len - len,
1373 select_mask, clear_mask,
1374 pl, default_match);
1375
1376 /* clear_c_f_dir eats a whole dir already? */
1377 if (processed) {
1378 cache += processed;
1379 strbuf_setlen(prefix, prefix->len - len);
1380 continue;
1381 }
1382
1383 strbuf_addch(prefix, '/');
1384 cache += clear_ce_flags_1(istate, cache, cache_end - cache,
1385 prefix,
1386 select_mask, clear_mask, pl,
1387 default_match);
1388 strbuf_setlen(prefix, prefix->len - len - 1);
1389 continue;
1390 }
1391
1392 /* Non-directory */
1393 dtype = ce_to_dtype(ce);
1394 ret = path_matches_pattern_list(ce->name,
1395 ce_namelen(ce),
1396 name, &dtype, pl, istate);
1397 if (ret == UNDECIDED)
1398 ret = default_match;
1399 if (ret == MATCHED)
1400 ce->ce_flags &= ~clear_mask;
1401 cache++;
1402 }
1403 return nr - (cache_end - cache);
1404 }
1405
1406 static int clear_ce_flags(struct index_state *istate,
1407 int select_mask, int clear_mask,
1408 struct pattern_list *pl)
1409 {
1410 static struct strbuf prefix = STRBUF_INIT;
1411
1412 strbuf_reset(&prefix);
1413
1414 return clear_ce_flags_1(istate,
1415 istate->cache,
1416 istate->cache_nr,
1417 &prefix,
1418 select_mask, clear_mask,
1419 pl, 0);
1420 }
1421
1422 /*
1423 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
1424 */
1425 static void mark_new_skip_worktree(struct pattern_list *pl,
1426 struct index_state *istate,
1427 int select_flag, int skip_wt_flag)
1428 {
1429 int i;
1430
1431 /*
1432 * 1. Pretend the narrowest worktree: only unmerged entries
1433 * are checked out
1434 */
1435 for (i = 0; i < istate->cache_nr; i++) {
1436 struct cache_entry *ce = istate->cache[i];
1437
1438 if (select_flag && !(ce->ce_flags & select_flag))
1439 continue;
1440
1441 if (!ce_stage(ce) && !(ce->ce_flags & CE_CONFLICTED))
1442 ce->ce_flags |= skip_wt_flag;
1443 else
1444 ce->ce_flags &= ~skip_wt_flag;
1445 }
1446
1447 /*
1448 * 2. Widen worktree according to sparse-checkout file.
1449 * Matched entries will have skip_wt_flag cleared (i.e. "in")
1450 */
1451 clear_ce_flags(istate, select_flag, skip_wt_flag, pl);
1452 }
1453
1454 static int verify_absent(const struct cache_entry *,
1455 enum unpack_trees_error_types,
1456 struct unpack_trees_options *);
1457 /*
1458 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
1459 * resulting index, -2 on failure to reflect the changes to the work tree.
1460 *
1461 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
1462 */
1463 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
1464 {
1465 int i, ret;
1466 static struct cache_entry *dfc;
1467 struct pattern_list pl;
1468
1469 if (len > MAX_UNPACK_TREES)
1470 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1471
1472 trace_performance_enter();
1473 memset(&pl, 0, sizeof(pl));
1474 if (!core_apply_sparse_checkout || !o->update)
1475 o->skip_sparse_checkout = 1;
1476 if (!o->skip_sparse_checkout) {
1477 char *sparse = git_pathdup("info/sparse-checkout");
1478 if (add_patterns_from_file_to_list(sparse, "", 0, &pl, NULL) < 0)
1479 o->skip_sparse_checkout = 1;
1480 else
1481 o->pl = &pl;
1482 free(sparse);
1483 }
1484
1485 memset(&o->result, 0, sizeof(o->result));
1486 o->result.initialized = 1;
1487 o->result.timestamp.sec = o->src_index->timestamp.sec;
1488 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1489 o->result.version = o->src_index->version;
1490 if (!o->src_index->split_index) {
1491 o->result.split_index = NULL;
1492 } else if (o->src_index == o->dst_index) {
1493 /*
1494 * o->dst_index (and thus o->src_index) will be discarded
1495 * and overwritten with o->result at the end of this function,
1496 * so just use src_index's split_index to avoid having to
1497 * create a new one.
1498 */
1499 o->result.split_index = o->src_index->split_index;
1500 o->result.split_index->refcount++;
1501 } else {
1502 o->result.split_index = init_split_index(&o->result);
1503 }
1504 oidcpy(&o->result.oid, &o->src_index->oid);
1505 o->merge_size = len;
1506 mark_all_ce_unused(o->src_index);
1507
1508 /*
1509 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1510 */
1511 if (!o->skip_sparse_checkout)
1512 mark_new_skip_worktree(o->pl, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1513
1514 if (!dfc)
1515 dfc = xcalloc(1, cache_entry_size(0));
1516 o->df_conflict_entry = dfc;
1517
1518 if (len) {
1519 const char *prefix = o->prefix ? o->prefix : "";
1520 struct traverse_info info;
1521
1522 setup_traverse_info(&info, prefix);
1523 info.fn = unpack_callback;
1524 info.data = o;
1525 info.show_all_errors = o->show_all_errors;
1526 info.pathspec = o->pathspec;
1527
1528 if (o->prefix) {
1529 /*
1530 * Unpack existing index entries that sort before the
1531 * prefix the tree is spliced into. Note that o->merge
1532 * is always true in this case.
1533 */
1534 while (1) {
1535 struct cache_entry *ce = next_cache_entry(o);
1536 if (!ce)
1537 break;
1538 if (ce_in_traverse_path(ce, &info))
1539 break;
1540 if (unpack_index_entry(ce, o) < 0)
1541 goto return_failed;
1542 }
1543 }
1544
1545 trace_performance_enter();
1546 ret = traverse_trees(o->src_index, len, t, &info);
1547 trace_performance_leave("traverse_trees");
1548 if (ret < 0)
1549 goto return_failed;
1550 }
1551
1552 /* Any left-over entries in the index? */
1553 if (o->merge) {
1554 while (1) {
1555 struct cache_entry *ce = next_cache_entry(o);
1556 if (!ce)
1557 break;
1558 if (unpack_index_entry(ce, o) < 0)
1559 goto return_failed;
1560 }
1561 }
1562 mark_all_ce_unused(o->src_index);
1563
1564 if (o->trivial_merges_only && o->nontrivial_merge) {
1565 ret = unpack_failed(o, "Merge requires file-level merging");
1566 goto done;
1567 }
1568
1569 if (!o->skip_sparse_checkout) {
1570 int empty_worktree = 1;
1571
1572 /*
1573 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1574 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1575 * so apply_sparse_checkout() won't attempt to remove it from worktree
1576 */
1577 mark_new_skip_worktree(o->pl, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1578
1579 ret = 0;
1580 for (i = 0; i < o->result.cache_nr; i++) {
1581 struct cache_entry *ce = o->result.cache[i];
1582
1583 /*
1584 * Entries marked with CE_ADDED in merged_entry() do not have
1585 * verify_absent() check (the check is effectively disabled
1586 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1587 *
1588 * Do the real check now because we have had
1589 * correct CE_NEW_SKIP_WORKTREE
1590 */
1591 if (ce->ce_flags & CE_ADDED &&
1592 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1593 if (!o->show_all_errors)
1594 goto return_failed;
1595 ret = -1;
1596 }
1597
1598 if (apply_sparse_checkout(&o->result, ce, o)) {
1599 if (!o->show_all_errors)
1600 goto return_failed;
1601 ret = -1;
1602 }
1603 if (!ce_skip_worktree(ce))
1604 empty_worktree = 0;
1605
1606 }
1607 if (ret < 0)
1608 goto return_failed;
1609 /*
1610 * Sparse checkout is meant to narrow down checkout area
1611 * but it does not make sense to narrow down to empty working
1612 * tree. This is usually a mistake in sparse checkout rules.
1613 * Do not allow users to do that.
1614 */
1615 if (o->result.cache_nr && empty_worktree) {
1616 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1617 goto done;
1618 }
1619 }
1620
1621 ret = check_updates(o) ? (-2) : 0;
1622 if (o->dst_index) {
1623 move_index_extensions(&o->result, o->src_index);
1624 if (!ret) {
1625 if (git_env_bool("GIT_TEST_CHECK_CACHE_TREE", 0))
1626 cache_tree_verify(the_repository, &o->result);
1627 if (!o->result.cache_tree)
1628 o->result.cache_tree = cache_tree();
1629 if (!cache_tree_fully_valid(o->result.cache_tree))
1630 cache_tree_update(&o->result,
1631 WRITE_TREE_SILENT |
1632 WRITE_TREE_REPAIR);
1633 }
1634
1635 o->result.updated_workdir = 1;
1636 discard_index(o->dst_index);
1637 *o->dst_index = o->result;
1638 } else {
1639 discard_index(&o->result);
1640 }
1641 o->src_index = NULL;
1642
1643 done:
1644 trace_performance_leave("unpack_trees");
1645 clear_pattern_list(&pl);
1646 return ret;
1647
1648 return_failed:
1649 if (o->show_all_errors)
1650 display_error_msgs(o);
1651 mark_all_ce_unused(o->src_index);
1652 ret = unpack_failed(o, NULL);
1653 if (o->exiting_early)
1654 ret = 0;
1655 goto done;
1656 }
1657
1658 /* Here come the merge functions */
1659
1660 static int reject_merge(const struct cache_entry *ce,
1661 struct unpack_trees_options *o)
1662 {
1663 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1664 }
1665
1666 static int same(const struct cache_entry *a, const struct cache_entry *b)
1667 {
1668 if (!!a != !!b)
1669 return 0;
1670 if (!a && !b)
1671 return 1;
1672 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1673 return 0;
1674 return a->ce_mode == b->ce_mode &&
1675 oideq(&a->oid, &b->oid);
1676 }
1677
1678
1679 /*
1680 * When a CE gets turned into an unmerged entry, we
1681 * want it to be up-to-date
1682 */
1683 static int verify_uptodate_1(const struct cache_entry *ce,
1684 struct unpack_trees_options *o,
1685 enum unpack_trees_error_types error_type)
1686 {
1687 struct stat st;
1688
1689 if (o->index_only)
1690 return 0;
1691
1692 /*
1693 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1694 * if this entry is truly up-to-date because this file may be
1695 * overwritten.
1696 */
1697 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1698 ; /* keep checking */
1699 else if (o->reset || ce_uptodate(ce))
1700 return 0;
1701
1702 if (!lstat(ce->name, &st)) {
1703 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1704 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1705
1706 if (submodule_from_ce(ce)) {
1707 int r = check_submodule_move_head(ce,
1708 "HEAD", oid_to_hex(&ce->oid), o);
1709 if (r)
1710 return add_rejected_path(o, error_type, ce->name);
1711 return 0;
1712 }
1713
1714 if (!changed)
1715 return 0;
1716 /*
1717 * Historic default policy was to allow submodule to be out
1718 * of sync wrt the superproject index. If the submodule was
1719 * not considered interesting above, we don't care here.
1720 */
1721 if (S_ISGITLINK(ce->ce_mode))
1722 return 0;
1723
1724 errno = 0;
1725 }
1726 if (errno == ENOENT)
1727 return 0;
1728 return add_rejected_path(o, error_type, ce->name);
1729 }
1730
1731 int verify_uptodate(const struct cache_entry *ce,
1732 struct unpack_trees_options *o)
1733 {
1734 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1735 return 0;
1736 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1737 }
1738
1739 static int verify_uptodate_sparse(const struct cache_entry *ce,
1740 struct unpack_trees_options *o)
1741 {
1742 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1743 }
1744
1745 /*
1746 * TODO: We should actually invalidate o->result, not src_index [1].
1747 * But since cache tree and untracked cache both are not copied to
1748 * o->result until unpacking is complete, we invalidate them on
1749 * src_index instead with the assumption that they will be copied to
1750 * dst_index at the end.
1751 *
1752 * [1] src_index->cache_tree is also used in unpack_callback() so if
1753 * we invalidate o->result, we need to update it to use
1754 * o->result.cache_tree as well.
1755 */
1756 static void invalidate_ce_path(const struct cache_entry *ce,
1757 struct unpack_trees_options *o)
1758 {
1759 if (!ce)
1760 return;
1761 cache_tree_invalidate_path(o->src_index, ce->name);
1762 untracked_cache_invalidate_path(o->src_index, ce->name, 1);
1763 }
1764
1765 /*
1766 * Check that checking out ce->sha1 in subdir ce->name is not
1767 * going to overwrite any working files.
1768 *
1769 * Currently, git does not checkout subprojects during a superproject
1770 * checkout, so it is not going to overwrite anything.
1771 */
1772 static int verify_clean_submodule(const char *old_sha1,
1773 const struct cache_entry *ce,
1774 struct unpack_trees_options *o)
1775 {
1776 if (!submodule_from_ce(ce))
1777 return 0;
1778
1779 return check_submodule_move_head(ce, old_sha1,
1780 oid_to_hex(&ce->oid), o);
1781 }
1782
1783 static int verify_clean_subdirectory(const struct cache_entry *ce,
1784 struct unpack_trees_options *o)
1785 {
1786 /*
1787 * we are about to extract "ce->name"; we would not want to lose
1788 * anything in the existing directory there.
1789 */
1790 int namelen;
1791 int i;
1792 struct dir_struct d;
1793 char *pathbuf;
1794 int cnt = 0;
1795
1796 if (S_ISGITLINK(ce->ce_mode)) {
1797 struct object_id oid;
1798 int sub_head = resolve_gitlink_ref(ce->name, "HEAD", &oid);
1799 /*
1800 * If we are not going to update the submodule, then
1801 * we don't care.
1802 */
1803 if (!sub_head && oideq(&oid, &ce->oid))
1804 return 0;
1805 return verify_clean_submodule(sub_head ? NULL : oid_to_hex(&oid),
1806 ce, o);
1807 }
1808
1809 /*
1810 * First let's make sure we do not have a local modification
1811 * in that directory.
1812 */
1813 namelen = ce_namelen(ce);
1814 for (i = locate_in_src_index(ce, o);
1815 i < o->src_index->cache_nr;
1816 i++) {
1817 struct cache_entry *ce2 = o->src_index->cache[i];
1818 int len = ce_namelen(ce2);
1819 if (len < namelen ||
1820 strncmp(ce->name, ce2->name, namelen) ||
1821 ce2->name[namelen] != '/')
1822 break;
1823 /*
1824 * ce2->name is an entry in the subdirectory to be
1825 * removed.
1826 */
1827 if (!ce_stage(ce2)) {
1828 if (verify_uptodate(ce2, o))
1829 return -1;
1830 add_entry(o, ce2, CE_REMOVE, 0);
1831 invalidate_ce_path(ce, o);
1832 mark_ce_used(ce2, o);
1833 }
1834 cnt++;
1835 }
1836
1837 /*
1838 * Then we need to make sure that we do not lose a locally
1839 * present file that is not ignored.
1840 */
1841 pathbuf = xstrfmt("%.*s/", namelen, ce->name);
1842
1843 memset(&d, 0, sizeof(d));
1844 if (o->dir)
1845 d.exclude_per_dir = o->dir->exclude_per_dir;
1846 i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL);
1847 if (i)
1848 return add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1849 free(pathbuf);
1850 return cnt;
1851 }
1852
1853 /*
1854 * This gets called when there was no index entry for the tree entry 'dst',
1855 * but we found a file in the working tree that 'lstat()' said was fine,
1856 * and we're on a case-insensitive filesystem.
1857 *
1858 * See if we can find a case-insensitive match in the index that also
1859 * matches the stat information, and assume it's that other file!
1860 */
1861 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1862 {
1863 const struct cache_entry *src;
1864
1865 src = index_file_exists(o->src_index, name, len, 1);
1866 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1867 }
1868
1869 static int check_ok_to_remove(const char *name, int len, int dtype,
1870 const struct cache_entry *ce, struct stat *st,
1871 enum unpack_trees_error_types error_type,
1872 struct unpack_trees_options *o)
1873 {
1874 const struct cache_entry *result;
1875
1876 /*
1877 * It may be that the 'lstat()' succeeded even though
1878 * target 'ce' was absent, because there is an old
1879 * entry that is different only in case..
1880 *
1881 * Ignore that lstat() if it matches.
1882 */
1883 if (ignore_case && icase_exists(o, name, len, st))
1884 return 0;
1885
1886 if (o->dir &&
1887 is_excluded(o->dir, o->src_index, name, &dtype))
1888 /*
1889 * ce->name is explicitly excluded, so it is Ok to
1890 * overwrite it.
1891 */
1892 return 0;
1893 if (S_ISDIR(st->st_mode)) {
1894 /*
1895 * We are checking out path "foo" and
1896 * found "foo/." in the working tree.
1897 * This is tricky -- if we have modified
1898 * files that are in "foo/" we would lose
1899 * them.
1900 */
1901 if (verify_clean_subdirectory(ce, o) < 0)
1902 return -1;
1903 return 0;
1904 }
1905
1906 /*
1907 * The previous round may already have decided to
1908 * delete this path, which is in a subdirectory that
1909 * is being replaced with a blob.
1910 */
1911 result = index_file_exists(&o->result, name, len, 0);
1912 if (result) {
1913 if (result->ce_flags & CE_REMOVE)
1914 return 0;
1915 }
1916
1917 return add_rejected_path(o, error_type, name);
1918 }
1919
1920 /*
1921 * We do not want to remove or overwrite a working tree file that
1922 * is not tracked, unless it is ignored.
1923 */
1924 static int verify_absent_1(const struct cache_entry *ce,
1925 enum unpack_trees_error_types error_type,
1926 struct unpack_trees_options *o)
1927 {
1928 int len;
1929 struct stat st;
1930
1931 if (o->index_only || o->reset || !o->update)
1932 return 0;
1933
1934 len = check_leading_path(ce->name, ce_namelen(ce));
1935 if (!len)
1936 return 0;
1937 else if (len > 0) {
1938 char *path;
1939 int ret;
1940
1941 path = xmemdupz(ce->name, len);
1942 if (lstat(path, &st))
1943 ret = error_errno("cannot stat '%s'", path);
1944 else {
1945 if (submodule_from_ce(ce))
1946 ret = check_submodule_move_head(ce,
1947 oid_to_hex(&ce->oid),
1948 NULL, o);
1949 else
1950 ret = check_ok_to_remove(path, len, DT_UNKNOWN, NULL,
1951 &st, error_type, o);
1952 }
1953 free(path);
1954 return ret;
1955 } else if (lstat(ce->name, &st)) {
1956 if (errno != ENOENT)
1957 return error_errno("cannot stat '%s'", ce->name);
1958 return 0;
1959 } else {
1960 if (submodule_from_ce(ce))
1961 return check_submodule_move_head(ce, oid_to_hex(&ce->oid),
1962 NULL, o);
1963
1964 return check_ok_to_remove(ce->name, ce_namelen(ce),
1965 ce_to_dtype(ce), ce, &st,
1966 error_type, o);
1967 }
1968 }
1969
1970 static int verify_absent(const struct cache_entry *ce,
1971 enum unpack_trees_error_types error_type,
1972 struct unpack_trees_options *o)
1973 {
1974 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1975 return 0;
1976 return verify_absent_1(ce, error_type, o);
1977 }
1978
1979 static int verify_absent_sparse(const struct cache_entry *ce,
1980 enum unpack_trees_error_types error_type,
1981 struct unpack_trees_options *o)
1982 {
1983 enum unpack_trees_error_types orphaned_error = error_type;
1984 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1985 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1986
1987 return verify_absent_1(ce, orphaned_error, o);
1988 }
1989
1990 static int merged_entry(const struct cache_entry *ce,
1991 const struct cache_entry *old,
1992 struct unpack_trees_options *o)
1993 {
1994 int update = CE_UPDATE;
1995 struct cache_entry *merge = dup_cache_entry(ce, &o->result);
1996
1997 if (!old) {
1998 /*
1999 * New index entries. In sparse checkout, the following
2000 * verify_absent() will be delayed until after
2001 * traverse_trees() finishes in unpack_trees(), then:
2002 *
2003 * - CE_NEW_SKIP_WORKTREE will be computed correctly
2004 * - verify_absent() be called again, this time with
2005 * correct CE_NEW_SKIP_WORKTREE
2006 *
2007 * verify_absent() call here does nothing in sparse
2008 * checkout (i.e. o->skip_sparse_checkout == 0)
2009 */
2010 update |= CE_ADDED;
2011 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
2012
2013 if (verify_absent(merge,
2014 ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
2015 discard_cache_entry(merge);
2016 return -1;
2017 }
2018 invalidate_ce_path(merge, o);
2019
2020 if (submodule_from_ce(ce)) {
2021 int ret = check_submodule_move_head(ce, NULL,
2022 oid_to_hex(&ce->oid),
2023 o);
2024 if (ret)
2025 return ret;
2026 }
2027
2028 } else if (!(old->ce_flags & CE_CONFLICTED)) {
2029 /*
2030 * See if we can re-use the old CE directly?
2031 * That way we get the uptodate stat info.
2032 *
2033 * This also removes the UPDATE flag on a match; otherwise
2034 * we will end up overwriting local changes in the work tree.
2035 */
2036 if (same(old, merge)) {
2037 copy_cache_entry(merge, old);
2038 update = 0;
2039 } else {
2040 if (verify_uptodate(old, o)) {
2041 discard_cache_entry(merge);
2042 return -1;
2043 }
2044 /* Migrate old flags over */
2045 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
2046 invalidate_ce_path(old, o);
2047 }
2048
2049 if (submodule_from_ce(ce)) {
2050 int ret = check_submodule_move_head(ce, oid_to_hex(&old->oid),
2051 oid_to_hex(&ce->oid),
2052 o);
2053 if (ret)
2054 return ret;
2055 }
2056 } else {
2057 /*
2058 * Previously unmerged entry left as an existence
2059 * marker by read_index_unmerged();
2060 */
2061 invalidate_ce_path(old, o);
2062 }
2063
2064 do_add_entry(o, merge, update, CE_STAGEMASK);
2065 return 1;
2066 }
2067
2068 static int deleted_entry(const struct cache_entry *ce,
2069 const struct cache_entry *old,
2070 struct unpack_trees_options *o)
2071 {
2072 /* Did it exist in the index? */
2073 if (!old) {
2074 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2075 return -1;
2076 return 0;
2077 }
2078 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
2079 return -1;
2080 add_entry(o, ce, CE_REMOVE, 0);
2081 invalidate_ce_path(ce, o);
2082 return 1;
2083 }
2084
2085 static int keep_entry(const struct cache_entry *ce,
2086 struct unpack_trees_options *o)
2087 {
2088 add_entry(o, ce, 0, 0);
2089 if (ce_stage(ce))
2090 invalidate_ce_path(ce, o);
2091 return 1;
2092 }
2093
2094 #if DBRT_DEBUG
2095 static void show_stage_entry(FILE *o,
2096 const char *label, const struct cache_entry *ce)
2097 {
2098 if (!ce)
2099 fprintf(o, "%s (missing)\n", label);
2100 else
2101 fprintf(o, "%s%06o %s %d\t%s\n",
2102 label,
2103 ce->ce_mode,
2104 oid_to_hex(&ce->oid),
2105 ce_stage(ce),
2106 ce->name);
2107 }
2108 #endif
2109
2110 int threeway_merge(const struct cache_entry * const *stages,
2111 struct unpack_trees_options *o)
2112 {
2113 const struct cache_entry *index;
2114 const struct cache_entry *head;
2115 const struct cache_entry *remote = stages[o->head_idx + 1];
2116 int count;
2117 int head_match = 0;
2118 int remote_match = 0;
2119
2120 int df_conflict_head = 0;
2121 int df_conflict_remote = 0;
2122
2123 int any_anc_missing = 0;
2124 int no_anc_exists = 1;
2125 int i;
2126
2127 for (i = 1; i < o->head_idx; i++) {
2128 if (!stages[i] || stages[i] == o->df_conflict_entry)
2129 any_anc_missing = 1;
2130 else
2131 no_anc_exists = 0;
2132 }
2133
2134 index = stages[0];
2135 head = stages[o->head_idx];
2136
2137 if (head == o->df_conflict_entry) {
2138 df_conflict_head = 1;
2139 head = NULL;
2140 }
2141
2142 if (remote == o->df_conflict_entry) {
2143 df_conflict_remote = 1;
2144 remote = NULL;
2145 }
2146
2147 /*
2148 * First, if there's a #16 situation, note that to prevent #13
2149 * and #14.
2150 */
2151 if (!same(remote, head)) {
2152 for (i = 1; i < o->head_idx; i++) {
2153 if (same(stages[i], head)) {
2154 head_match = i;
2155 }
2156 if (same(stages[i], remote)) {
2157 remote_match = i;
2158 }
2159 }
2160 }
2161
2162 /*
2163 * We start with cases where the index is allowed to match
2164 * something other than the head: #14(ALT) and #2ALT, where it
2165 * is permitted to match the result instead.
2166 */
2167 /* #14, #14ALT, #2ALT */
2168 if (remote && !df_conflict_head && head_match && !remote_match) {
2169 if (index && !same(index, remote) && !same(index, head))
2170 return reject_merge(index, o);
2171 return merged_entry(remote, index, o);
2172 }
2173 /*
2174 * If we have an entry in the index cache, then we want to
2175 * make sure that it matches head.
2176 */
2177 if (index && !same(index, head))
2178 return reject_merge(index, o);
2179
2180 if (head) {
2181 /* #5ALT, #15 */
2182 if (same(head, remote))
2183 return merged_entry(head, index, o);
2184 /* #13, #3ALT */
2185 if (!df_conflict_remote && remote_match && !head_match)
2186 return merged_entry(head, index, o);
2187 }
2188
2189 /* #1 */
2190 if (!head && !remote && any_anc_missing)
2191 return 0;
2192
2193 /*
2194 * Under the "aggressive" rule, we resolve mostly trivial
2195 * cases that we historically had git-merge-one-file resolve.
2196 */
2197 if (o->aggressive) {
2198 int head_deleted = !head;
2199 int remote_deleted = !remote;
2200 const struct cache_entry *ce = NULL;
2201
2202 if (index)
2203 ce = index;
2204 else if (head)
2205 ce = head;
2206 else if (remote)
2207 ce = remote;
2208 else {
2209 for (i = 1; i < o->head_idx; i++) {
2210 if (stages[i] && stages[i] != o->df_conflict_entry) {
2211 ce = stages[i];
2212 break;
2213 }
2214 }
2215 }
2216
2217 /*
2218 * Deleted in both.
2219 * Deleted in one and unchanged in the other.
2220 */
2221 if ((head_deleted && remote_deleted) ||
2222 (head_deleted && remote && remote_match) ||
2223 (remote_deleted && head && head_match)) {
2224 if (index)
2225 return deleted_entry(index, index, o);
2226 if (ce && !head_deleted) {
2227 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2228 return -1;
2229 }
2230 return 0;
2231 }
2232 /*
2233 * Added in both, identically.
2234 */
2235 if (no_anc_exists && head && remote && same(head, remote))
2236 return merged_entry(head, index, o);
2237
2238 }
2239
2240 /* Below are "no merge" cases, which require that the index be
2241 * up-to-date to avoid the files getting overwritten with
2242 * conflict resolution files.
2243 */
2244 if (index) {
2245 if (verify_uptodate(index, o))
2246 return -1;
2247 }
2248
2249 o->nontrivial_merge = 1;
2250
2251 /* #2, #3, #4, #6, #7, #9, #10, #11. */
2252 count = 0;
2253 if (!head_match || !remote_match) {
2254 for (i = 1; i < o->head_idx; i++) {
2255 if (stages[i] && stages[i] != o->df_conflict_entry) {
2256 keep_entry(stages[i], o);
2257 count++;
2258 break;
2259 }
2260 }
2261 }
2262 #if DBRT_DEBUG
2263 else {
2264 fprintf(stderr, "read-tree: warning #16 detected\n");
2265 show_stage_entry(stderr, "head ", stages[head_match]);
2266 show_stage_entry(stderr, "remote ", stages[remote_match]);
2267 }
2268 #endif
2269 if (head) { count += keep_entry(head, o); }
2270 if (remote) { count += keep_entry(remote, o); }
2271 return count;
2272 }
2273
2274 /*
2275 * Two-way merge.
2276 *
2277 * The rule is to "carry forward" what is in the index without losing
2278 * information across a "fast-forward", favoring a successful merge
2279 * over a merge failure when it makes sense. For details of the
2280 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
2281 *
2282 */
2283 int twoway_merge(const struct cache_entry * const *src,
2284 struct unpack_trees_options *o)
2285 {
2286 const struct cache_entry *current = src[0];
2287 const struct cache_entry *oldtree = src[1];
2288 const struct cache_entry *newtree = src[2];
2289
2290 if (o->merge_size != 2)
2291 return error("Cannot do a twoway merge of %d trees",
2292 o->merge_size);
2293
2294 if (oldtree == o->df_conflict_entry)
2295 oldtree = NULL;
2296 if (newtree == o->df_conflict_entry)
2297 newtree = NULL;
2298
2299 if (current) {
2300 if (current->ce_flags & CE_CONFLICTED) {
2301 if (same(oldtree, newtree) || o->reset) {
2302 if (!newtree)
2303 return deleted_entry(current, current, o);
2304 else
2305 return merged_entry(newtree, current, o);
2306 }
2307 return reject_merge(current, o);
2308 } else if ((!oldtree && !newtree) || /* 4 and 5 */
2309 (!oldtree && newtree &&
2310 same(current, newtree)) || /* 6 and 7 */
2311 (oldtree && newtree &&
2312 same(oldtree, newtree)) || /* 14 and 15 */
2313 (oldtree && newtree &&
2314 !same(oldtree, newtree) && /* 18 and 19 */
2315 same(current, newtree))) {
2316 return keep_entry(current, o);
2317 } else if (oldtree && !newtree && same(current, oldtree)) {
2318 /* 10 or 11 */
2319 return deleted_entry(oldtree, current, o);
2320 } else if (oldtree && newtree &&
2321 same(current, oldtree) && !same(current, newtree)) {
2322 /* 20 or 21 */
2323 return merged_entry(newtree, current, o);
2324 } else
2325 return reject_merge(current, o);
2326 }
2327 else if (newtree) {
2328 if (oldtree && !o->initial_checkout) {
2329 /*
2330 * deletion of the path was staged;
2331 */
2332 if (same(oldtree, newtree))
2333 return 1;
2334 return reject_merge(oldtree, o);
2335 }
2336 return merged_entry(newtree, current, o);
2337 }
2338 return deleted_entry(oldtree, current, o);
2339 }
2340
2341 /*
2342 * Bind merge.
2343 *
2344 * Keep the index entries at stage0, collapse stage1 but make sure
2345 * stage0 does not have anything there.
2346 */
2347 int bind_merge(const struct cache_entry * const *src,
2348 struct unpack_trees_options *o)
2349 {
2350 const struct cache_entry *old = src[0];
2351 const struct cache_entry *a = src[1];
2352
2353 if (o->merge_size != 1)
2354 return error("Cannot do a bind merge of %d trees",
2355 o->merge_size);
2356 if (a && old)
2357 return o->quiet ? -1 :
2358 error(ERRORMSG(o, ERROR_BIND_OVERLAP),
2359 super_prefixed(a->name),
2360 super_prefixed(old->name));
2361 if (!a)
2362 return keep_entry(old, o);
2363 else
2364 return merged_entry(a, NULL, o);
2365 }
2366
2367 /*
2368 * One-way merge.
2369 *
2370 * The rule is:
2371 * - take the stat information from stage0, take the data from stage1
2372 */
2373 int oneway_merge(const struct cache_entry * const *src,
2374 struct unpack_trees_options *o)
2375 {
2376 const struct cache_entry *old = src[0];
2377 const struct cache_entry *a = src[1];
2378
2379 if (o->merge_size != 1)
2380 return error("Cannot do a oneway merge of %d trees",
2381 o->merge_size);
2382
2383 if (!a || a == o->df_conflict_entry)
2384 return deleted_entry(old, old, o);
2385
2386 if (old && same(old, a)) {
2387 int update = 0;
2388 if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
2389 struct stat st;
2390 if (lstat(old->name, &st) ||
2391 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
2392 update |= CE_UPDATE;
2393 }
2394 if (o->update && S_ISGITLINK(old->ce_mode) &&
2395 should_update_submodules() && !verify_uptodate(old, o))
2396 update |= CE_UPDATE;
2397 add_entry(o, old, update, CE_STAGEMASK);
2398 return 0;
2399 }
2400 return merged_entry(a, old, o);
2401 }