tree-walk: add a strbuf wrapper for make_traverse_path()
[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 "fetch-object.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(_("Checking out 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 (repository_format_partial_clone && 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 fetch_objects(repository_format_partial_clone,
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(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 make_traverse_path(ce->name, info, n->path, n->pathlen);
972
973 return ce;
974 }
975
976 /*
977 * Note that traverse_by_cache_tree() duplicates some logic in this function
978 * without actually calling it. If you change the logic here you may need to
979 * check and change there as well.
980 */
981 static int unpack_nondirectories(int n, unsigned long mask,
982 unsigned long dirmask,
983 struct cache_entry **src,
984 const struct name_entry *names,
985 const struct traverse_info *info)
986 {
987 int i;
988 struct unpack_trees_options *o = info->data;
989 unsigned long conflicts = info->df_conflicts | dirmask;
990
991 /* Do we have *only* directories? Nothing to do */
992 if (mask == dirmask && !src[0])
993 return 0;
994
995 /*
996 * Ok, we've filled in up to any potential index entry in src[0],
997 * now do the rest.
998 */
999 for (i = 0; i < n; i++) {
1000 int stage;
1001 unsigned int bit = 1ul << i;
1002 if (conflicts & bit) {
1003 src[i + o->merge] = o->df_conflict_entry;
1004 continue;
1005 }
1006 if (!(mask & bit))
1007 continue;
1008 if (!o->merge)
1009 stage = 0;
1010 else if (i + 1 < o->head_idx)
1011 stage = 1;
1012 else if (i + 1 > o->head_idx)
1013 stage = 3;
1014 else
1015 stage = 2;
1016
1017 /*
1018 * If the merge bit is set, then the cache entries are
1019 * discarded in the following block. In this case,
1020 * construct "transient" cache_entries, as they are
1021 * not stored in the index. otherwise construct the
1022 * cache entry from the index aware logic.
1023 */
1024 src[i + o->merge] = create_ce_entry(info, names + i, stage, &o->result, o->merge);
1025 }
1026
1027 if (o->merge) {
1028 int rc = call_unpack_fn((const struct cache_entry * const *)src,
1029 o);
1030 for (i = 0; i < n; i++) {
1031 struct cache_entry *ce = src[i + o->merge];
1032 if (ce != o->df_conflict_entry)
1033 discard_cache_entry(ce);
1034 }
1035 return rc;
1036 }
1037
1038 for (i = 0; i < n; i++)
1039 if (src[i] && src[i] != o->df_conflict_entry)
1040 if (do_add_entry(o, src[i], 0, 0))
1041 return -1;
1042
1043 return 0;
1044 }
1045
1046 static int unpack_failed(struct unpack_trees_options *o, const char *message)
1047 {
1048 discard_index(&o->result);
1049 if (!o->quiet && !o->exiting_early) {
1050 if (message)
1051 return error("%s", message);
1052 return -1;
1053 }
1054 return -1;
1055 }
1056
1057 /*
1058 * The tree traversal is looking at name p. If we have a matching entry,
1059 * return it. If name p is a directory in the index, do not return
1060 * anything, as we will want to match it when the traversal descends into
1061 * the directory.
1062 */
1063 static int find_cache_pos(struct traverse_info *info,
1064 const char *p, size_t p_len)
1065 {
1066 int pos;
1067 struct unpack_trees_options *o = info->data;
1068 struct index_state *index = o->src_index;
1069 int pfxlen = info->pathlen;
1070
1071 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
1072 const struct cache_entry *ce = index->cache[pos];
1073 const char *ce_name, *ce_slash;
1074 int cmp, ce_len;
1075
1076 if (ce->ce_flags & CE_UNPACKED) {
1077 /*
1078 * cache_bottom entry is already unpacked, so
1079 * we can never match it; don't check it
1080 * again.
1081 */
1082 if (pos == o->cache_bottom)
1083 ++o->cache_bottom;
1084 continue;
1085 }
1086 if (!ce_in_traverse_path(ce, info)) {
1087 /*
1088 * Check if we can skip future cache checks
1089 * (because we're already past all possible
1090 * entries in the traverse path).
1091 */
1092 if (info->traverse_path) {
1093 if (strncmp(ce->name, info->traverse_path,
1094 info->pathlen) > 0)
1095 break;
1096 }
1097 continue;
1098 }
1099 ce_name = ce->name + pfxlen;
1100 ce_slash = strchr(ce_name, '/');
1101 if (ce_slash)
1102 ce_len = ce_slash - ce_name;
1103 else
1104 ce_len = ce_namelen(ce) - pfxlen;
1105 cmp = name_compare(p, p_len, ce_name, ce_len);
1106 /*
1107 * Exact match; if we have a directory we need to
1108 * delay returning it.
1109 */
1110 if (!cmp)
1111 return ce_slash ? -2 - pos : pos;
1112 if (0 < cmp)
1113 continue; /* keep looking */
1114 /*
1115 * ce_name sorts after p->path; could it be that we
1116 * have files under p->path directory in the index?
1117 * E.g. ce_name == "t-i", and p->path == "t"; we may
1118 * have "t/a" in the index.
1119 */
1120 if (p_len < ce_len && !memcmp(ce_name, p, p_len) &&
1121 ce_name[p_len] < '/')
1122 continue; /* keep looking */
1123 break;
1124 }
1125 return -1;
1126 }
1127
1128 static struct cache_entry *find_cache_entry(struct traverse_info *info,
1129 const struct name_entry *p)
1130 {
1131 int pos = find_cache_pos(info, p->path, p->pathlen);
1132 struct unpack_trees_options *o = info->data;
1133
1134 if (0 <= pos)
1135 return o->src_index->cache[pos];
1136 else
1137 return NULL;
1138 }
1139
1140 static void debug_path(struct traverse_info *info)
1141 {
1142 if (info->prev) {
1143 debug_path(info->prev);
1144 if (*info->prev->name)
1145 putchar('/');
1146 }
1147 printf("%s", info->name);
1148 }
1149
1150 static void debug_name_entry(int i, struct name_entry *n)
1151 {
1152 printf("ent#%d %06o %s\n", i,
1153 n->path ? n->mode : 0,
1154 n->path ? n->path : "(missing)");
1155 }
1156
1157 static void debug_unpack_callback(int n,
1158 unsigned long mask,
1159 unsigned long dirmask,
1160 struct name_entry *names,
1161 struct traverse_info *info)
1162 {
1163 int i;
1164 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
1165 mask, dirmask, n);
1166 debug_path(info);
1167 putchar('\n');
1168 for (i = 0; i < n; i++)
1169 debug_name_entry(i, names + i);
1170 }
1171
1172 /*
1173 * Note that traverse_by_cache_tree() duplicates some logic in this function
1174 * without actually calling it. If you change the logic here you may need to
1175 * check and change there as well.
1176 */
1177 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
1178 {
1179 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
1180 struct unpack_trees_options *o = info->data;
1181 const struct name_entry *p = names;
1182
1183 /* Find first entry with a real name (we could use "mask" too) */
1184 while (!p->mode)
1185 p++;
1186
1187 if (o->debug_unpack)
1188 debug_unpack_callback(n, mask, dirmask, names, info);
1189
1190 /* Are we supposed to look at the index too? */
1191 if (o->merge) {
1192 while (1) {
1193 int cmp;
1194 struct cache_entry *ce;
1195
1196 if (o->diff_index_cached)
1197 ce = next_cache_entry(o);
1198 else
1199 ce = find_cache_entry(info, p);
1200
1201 if (!ce)
1202 break;
1203 cmp = compare_entry(ce, info, p);
1204 if (cmp < 0) {
1205 if (unpack_index_entry(ce, o) < 0)
1206 return unpack_failed(o, NULL);
1207 continue;
1208 }
1209 if (!cmp) {
1210 if (ce_stage(ce)) {
1211 /*
1212 * If we skip unmerged index
1213 * entries, we'll skip this
1214 * entry *and* the tree
1215 * entries associated with it!
1216 */
1217 if (o->skip_unmerged) {
1218 add_same_unmerged(ce, o);
1219 return mask;
1220 }
1221 }
1222 src[0] = ce;
1223 }
1224 break;
1225 }
1226 }
1227
1228 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
1229 return -1;
1230
1231 if (o->merge && src[0]) {
1232 if (ce_stage(src[0]))
1233 mark_ce_used_same_name(src[0], o);
1234 else
1235 mark_ce_used(src[0], o);
1236 }
1237
1238 /* Now handle any directories.. */
1239 if (dirmask) {
1240 /* special case: "diff-index --cached" looking at a tree */
1241 if (o->diff_index_cached &&
1242 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
1243 int matches;
1244 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
1245 names, info);
1246 /*
1247 * Everything under the name matches; skip the
1248 * entire hierarchy. diff_index_cached codepath
1249 * special cases D/F conflicts in such a way that
1250 * it does not do any look-ahead, so this is safe.
1251 */
1252 if (matches) {
1253 o->cache_bottom += matches;
1254 return mask;
1255 }
1256 }
1257
1258 if (traverse_trees_recursive(n, dirmask, mask & ~dirmask,
1259 names, info) < 0)
1260 return -1;
1261 return mask;
1262 }
1263
1264 return mask;
1265 }
1266
1267 static int clear_ce_flags_1(struct index_state *istate,
1268 struct cache_entry **cache, int nr,
1269 struct strbuf *prefix,
1270 int select_mask, int clear_mask,
1271 struct exclude_list *el, int defval);
1272
1273 /* Whole directory matching */
1274 static int clear_ce_flags_dir(struct index_state *istate,
1275 struct cache_entry **cache, int nr,
1276 struct strbuf *prefix,
1277 char *basename,
1278 int select_mask, int clear_mask,
1279 struct exclude_list *el, int defval)
1280 {
1281 struct cache_entry **cache_end;
1282 int dtype = DT_DIR;
1283 int ret = is_excluded_from_list(prefix->buf, prefix->len,
1284 basename, &dtype, el, istate);
1285 int rc;
1286
1287 strbuf_addch(prefix, '/');
1288
1289 /* If undecided, use matching result of parent dir in defval */
1290 if (ret < 0)
1291 ret = defval;
1292
1293 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
1294 struct cache_entry *ce = *cache_end;
1295 if (strncmp(ce->name, prefix->buf, prefix->len))
1296 break;
1297 }
1298
1299 /*
1300 * TODO: check el, if there are no patterns that may conflict
1301 * with ret (iow, we know in advance the incl/excl
1302 * decision for the entire directory), clear flag here without
1303 * calling clear_ce_flags_1(). That function will call
1304 * the expensive is_excluded_from_list() on every entry.
1305 */
1306 rc = clear_ce_flags_1(istate, cache, cache_end - cache,
1307 prefix,
1308 select_mask, clear_mask,
1309 el, ret);
1310 strbuf_setlen(prefix, prefix->len - 1);
1311 return rc;
1312 }
1313
1314 /*
1315 * Traverse the index, find every entry that matches according to
1316 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
1317 * number of traversed entries.
1318 *
1319 * If select_mask is non-zero, only entries whose ce_flags has on of
1320 * those bits enabled are traversed.
1321 *
1322 * cache : pointer to an index entry
1323 * prefix_len : an offset to its path
1324 *
1325 * The current path ("prefix") including the trailing '/' is
1326 * cache[0]->name[0..(prefix_len-1)]
1327 * Top level path has prefix_len zero.
1328 */
1329 static int clear_ce_flags_1(struct index_state *istate,
1330 struct cache_entry **cache, int nr,
1331 struct strbuf *prefix,
1332 int select_mask, int clear_mask,
1333 struct exclude_list *el, int defval)
1334 {
1335 struct cache_entry **cache_end = cache + nr;
1336
1337 /*
1338 * Process all entries that have the given prefix and meet
1339 * select_mask condition
1340 */
1341 while(cache != cache_end) {
1342 struct cache_entry *ce = *cache;
1343 const char *name, *slash;
1344 int len, dtype, ret;
1345
1346 if (select_mask && !(ce->ce_flags & select_mask)) {
1347 cache++;
1348 continue;
1349 }
1350
1351 if (prefix->len && strncmp(ce->name, prefix->buf, prefix->len))
1352 break;
1353
1354 name = ce->name + prefix->len;
1355 slash = strchr(name, '/');
1356
1357 /* If it's a directory, try whole directory match first */
1358 if (slash) {
1359 int processed;
1360
1361 len = slash - name;
1362 strbuf_add(prefix, name, len);
1363
1364 processed = clear_ce_flags_dir(istate, cache, cache_end - cache,
1365 prefix,
1366 prefix->buf + prefix->len - len,
1367 select_mask, clear_mask,
1368 el, defval);
1369
1370 /* clear_c_f_dir eats a whole dir already? */
1371 if (processed) {
1372 cache += processed;
1373 strbuf_setlen(prefix, prefix->len - len);
1374 continue;
1375 }
1376
1377 strbuf_addch(prefix, '/');
1378 cache += clear_ce_flags_1(istate, cache, cache_end - cache,
1379 prefix,
1380 select_mask, clear_mask, el, defval);
1381 strbuf_setlen(prefix, prefix->len - len - 1);
1382 continue;
1383 }
1384
1385 /* Non-directory */
1386 dtype = ce_to_dtype(ce);
1387 ret = is_excluded_from_list(ce->name, ce_namelen(ce),
1388 name, &dtype, el, istate);
1389 if (ret < 0)
1390 ret = defval;
1391 if (ret > 0)
1392 ce->ce_flags &= ~clear_mask;
1393 cache++;
1394 }
1395 return nr - (cache_end - cache);
1396 }
1397
1398 static int clear_ce_flags(struct index_state *istate,
1399 int select_mask, int clear_mask,
1400 struct exclude_list *el)
1401 {
1402 static struct strbuf prefix = STRBUF_INIT;
1403
1404 strbuf_reset(&prefix);
1405
1406 return clear_ce_flags_1(istate,
1407 istate->cache,
1408 istate->cache_nr,
1409 &prefix,
1410 select_mask, clear_mask,
1411 el, 0);
1412 }
1413
1414 /*
1415 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
1416 */
1417 static void mark_new_skip_worktree(struct exclude_list *el,
1418 struct index_state *istate,
1419 int select_flag, int skip_wt_flag)
1420 {
1421 int i;
1422
1423 /*
1424 * 1. Pretend the narrowest worktree: only unmerged entries
1425 * are checked out
1426 */
1427 for (i = 0; i < istate->cache_nr; i++) {
1428 struct cache_entry *ce = istate->cache[i];
1429
1430 if (select_flag && !(ce->ce_flags & select_flag))
1431 continue;
1432
1433 if (!ce_stage(ce) && !(ce->ce_flags & CE_CONFLICTED))
1434 ce->ce_flags |= skip_wt_flag;
1435 else
1436 ce->ce_flags &= ~skip_wt_flag;
1437 }
1438
1439 /*
1440 * 2. Widen worktree according to sparse-checkout file.
1441 * Matched entries will have skip_wt_flag cleared (i.e. "in")
1442 */
1443 clear_ce_flags(istate, select_flag, skip_wt_flag, el);
1444 }
1445
1446 static int verify_absent(const struct cache_entry *,
1447 enum unpack_trees_error_types,
1448 struct unpack_trees_options *);
1449 /*
1450 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
1451 * resulting index, -2 on failure to reflect the changes to the work tree.
1452 *
1453 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
1454 */
1455 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
1456 {
1457 int i, ret;
1458 static struct cache_entry *dfc;
1459 struct exclude_list el;
1460
1461 if (len > MAX_UNPACK_TREES)
1462 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1463
1464 trace_performance_enter();
1465 memset(&el, 0, sizeof(el));
1466 if (!core_apply_sparse_checkout || !o->update)
1467 o->skip_sparse_checkout = 1;
1468 if (!o->skip_sparse_checkout) {
1469 char *sparse = git_pathdup("info/sparse-checkout");
1470 if (add_excludes_from_file_to_list(sparse, "", 0, &el, NULL) < 0)
1471 o->skip_sparse_checkout = 1;
1472 else
1473 o->el = &el;
1474 free(sparse);
1475 }
1476
1477 memset(&o->result, 0, sizeof(o->result));
1478 o->result.initialized = 1;
1479 o->result.timestamp.sec = o->src_index->timestamp.sec;
1480 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1481 o->result.version = o->src_index->version;
1482 if (!o->src_index->split_index) {
1483 o->result.split_index = NULL;
1484 } else if (o->src_index == o->dst_index) {
1485 /*
1486 * o->dst_index (and thus o->src_index) will be discarded
1487 * and overwritten with o->result at the end of this function,
1488 * so just use src_index's split_index to avoid having to
1489 * create a new one.
1490 */
1491 o->result.split_index = o->src_index->split_index;
1492 o->result.split_index->refcount++;
1493 } else {
1494 o->result.split_index = init_split_index(&o->result);
1495 }
1496 oidcpy(&o->result.oid, &o->src_index->oid);
1497 o->merge_size = len;
1498 mark_all_ce_unused(o->src_index);
1499
1500 /*
1501 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1502 */
1503 if (!o->skip_sparse_checkout)
1504 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1505
1506 if (!dfc)
1507 dfc = xcalloc(1, cache_entry_size(0));
1508 o->df_conflict_entry = dfc;
1509
1510 if (len) {
1511 const char *prefix = o->prefix ? o->prefix : "";
1512 struct traverse_info info;
1513
1514 setup_traverse_info(&info, prefix);
1515 info.fn = unpack_callback;
1516 info.data = o;
1517 info.show_all_errors = o->show_all_errors;
1518 info.pathspec = o->pathspec;
1519
1520 if (o->prefix) {
1521 /*
1522 * Unpack existing index entries that sort before the
1523 * prefix the tree is spliced into. Note that o->merge
1524 * is always true in this case.
1525 */
1526 while (1) {
1527 struct cache_entry *ce = next_cache_entry(o);
1528 if (!ce)
1529 break;
1530 if (ce_in_traverse_path(ce, &info))
1531 break;
1532 if (unpack_index_entry(ce, o) < 0)
1533 goto return_failed;
1534 }
1535 }
1536
1537 trace_performance_enter();
1538 ret = traverse_trees(o->src_index, len, t, &info);
1539 trace_performance_leave("traverse_trees");
1540 if (ret < 0)
1541 goto return_failed;
1542 }
1543
1544 /* Any left-over entries in the index? */
1545 if (o->merge) {
1546 while (1) {
1547 struct cache_entry *ce = next_cache_entry(o);
1548 if (!ce)
1549 break;
1550 if (unpack_index_entry(ce, o) < 0)
1551 goto return_failed;
1552 }
1553 }
1554 mark_all_ce_unused(o->src_index);
1555
1556 if (o->trivial_merges_only && o->nontrivial_merge) {
1557 ret = unpack_failed(o, "Merge requires file-level merging");
1558 goto done;
1559 }
1560
1561 if (!o->skip_sparse_checkout) {
1562 int empty_worktree = 1;
1563
1564 /*
1565 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1566 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1567 * so apply_sparse_checkout() won't attempt to remove it from worktree
1568 */
1569 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1570
1571 ret = 0;
1572 for (i = 0; i < o->result.cache_nr; i++) {
1573 struct cache_entry *ce = o->result.cache[i];
1574
1575 /*
1576 * Entries marked with CE_ADDED in merged_entry() do not have
1577 * verify_absent() check (the check is effectively disabled
1578 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1579 *
1580 * Do the real check now because we have had
1581 * correct CE_NEW_SKIP_WORKTREE
1582 */
1583 if (ce->ce_flags & CE_ADDED &&
1584 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1585 if (!o->show_all_errors)
1586 goto return_failed;
1587 ret = -1;
1588 }
1589
1590 if (apply_sparse_checkout(&o->result, ce, o)) {
1591 if (!o->show_all_errors)
1592 goto return_failed;
1593 ret = -1;
1594 }
1595 if (!ce_skip_worktree(ce))
1596 empty_worktree = 0;
1597
1598 }
1599 if (ret < 0)
1600 goto return_failed;
1601 /*
1602 * Sparse checkout is meant to narrow down checkout area
1603 * but it does not make sense to narrow down to empty working
1604 * tree. This is usually a mistake in sparse checkout rules.
1605 * Do not allow users to do that.
1606 */
1607 if (o->result.cache_nr && empty_worktree) {
1608 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1609 goto done;
1610 }
1611 }
1612
1613 ret = check_updates(o) ? (-2) : 0;
1614 if (o->dst_index) {
1615 move_index_extensions(&o->result, o->src_index);
1616 if (!ret) {
1617 if (git_env_bool("GIT_TEST_CHECK_CACHE_TREE", 0))
1618 cache_tree_verify(the_repository, &o->result);
1619 if (!o->result.cache_tree)
1620 o->result.cache_tree = cache_tree();
1621 if (!cache_tree_fully_valid(o->result.cache_tree))
1622 cache_tree_update(&o->result,
1623 WRITE_TREE_SILENT |
1624 WRITE_TREE_REPAIR);
1625 }
1626
1627 o->result.updated_workdir = 1;
1628 discard_index(o->dst_index);
1629 *o->dst_index = o->result;
1630 } else {
1631 discard_index(&o->result);
1632 }
1633 o->src_index = NULL;
1634
1635 done:
1636 trace_performance_leave("unpack_trees");
1637 clear_exclude_list(&el);
1638 return ret;
1639
1640 return_failed:
1641 if (o->show_all_errors)
1642 display_error_msgs(o);
1643 mark_all_ce_unused(o->src_index);
1644 ret = unpack_failed(o, NULL);
1645 if (o->exiting_early)
1646 ret = 0;
1647 goto done;
1648 }
1649
1650 /* Here come the merge functions */
1651
1652 static int reject_merge(const struct cache_entry *ce,
1653 struct unpack_trees_options *o)
1654 {
1655 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1656 }
1657
1658 static int same(const struct cache_entry *a, const struct cache_entry *b)
1659 {
1660 if (!!a != !!b)
1661 return 0;
1662 if (!a && !b)
1663 return 1;
1664 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1665 return 0;
1666 return a->ce_mode == b->ce_mode &&
1667 oideq(&a->oid, &b->oid);
1668 }
1669
1670
1671 /*
1672 * When a CE gets turned into an unmerged entry, we
1673 * want it to be up-to-date
1674 */
1675 static int verify_uptodate_1(const struct cache_entry *ce,
1676 struct unpack_trees_options *o,
1677 enum unpack_trees_error_types error_type)
1678 {
1679 struct stat st;
1680
1681 if (o->index_only)
1682 return 0;
1683
1684 /*
1685 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1686 * if this entry is truly up-to-date because this file may be
1687 * overwritten.
1688 */
1689 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1690 ; /* keep checking */
1691 else if (o->reset || ce_uptodate(ce))
1692 return 0;
1693
1694 if (!lstat(ce->name, &st)) {
1695 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1696 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1697
1698 if (submodule_from_ce(ce)) {
1699 int r = check_submodule_move_head(ce,
1700 "HEAD", oid_to_hex(&ce->oid), o);
1701 if (r)
1702 return add_rejected_path(o, error_type, ce->name);
1703 return 0;
1704 }
1705
1706 if (!changed)
1707 return 0;
1708 /*
1709 * Historic default policy was to allow submodule to be out
1710 * of sync wrt the superproject index. If the submodule was
1711 * not considered interesting above, we don't care here.
1712 */
1713 if (S_ISGITLINK(ce->ce_mode))
1714 return 0;
1715
1716 errno = 0;
1717 }
1718 if (errno == ENOENT)
1719 return 0;
1720 return add_rejected_path(o, error_type, ce->name);
1721 }
1722
1723 int verify_uptodate(const struct cache_entry *ce,
1724 struct unpack_trees_options *o)
1725 {
1726 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1727 return 0;
1728 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1729 }
1730
1731 static int verify_uptodate_sparse(const struct cache_entry *ce,
1732 struct unpack_trees_options *o)
1733 {
1734 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1735 }
1736
1737 /*
1738 * TODO: We should actually invalidate o->result, not src_index [1].
1739 * But since cache tree and untracked cache both are not copied to
1740 * o->result until unpacking is complete, we invalidate them on
1741 * src_index instead with the assumption that they will be copied to
1742 * dst_index at the end.
1743 *
1744 * [1] src_index->cache_tree is also used in unpack_callback() so if
1745 * we invalidate o->result, we need to update it to use
1746 * o->result.cache_tree as well.
1747 */
1748 static void invalidate_ce_path(const struct cache_entry *ce,
1749 struct unpack_trees_options *o)
1750 {
1751 if (!ce)
1752 return;
1753 cache_tree_invalidate_path(o->src_index, ce->name);
1754 untracked_cache_invalidate_path(o->src_index, ce->name, 1);
1755 }
1756
1757 /*
1758 * Check that checking out ce->sha1 in subdir ce->name is not
1759 * going to overwrite any working files.
1760 *
1761 * Currently, git does not checkout subprojects during a superproject
1762 * checkout, so it is not going to overwrite anything.
1763 */
1764 static int verify_clean_submodule(const char *old_sha1,
1765 const struct cache_entry *ce,
1766 struct unpack_trees_options *o)
1767 {
1768 if (!submodule_from_ce(ce))
1769 return 0;
1770
1771 return check_submodule_move_head(ce, old_sha1,
1772 oid_to_hex(&ce->oid), o);
1773 }
1774
1775 static int verify_clean_subdirectory(const struct cache_entry *ce,
1776 struct unpack_trees_options *o)
1777 {
1778 /*
1779 * we are about to extract "ce->name"; we would not want to lose
1780 * anything in the existing directory there.
1781 */
1782 int namelen;
1783 int i;
1784 struct dir_struct d;
1785 char *pathbuf;
1786 int cnt = 0;
1787
1788 if (S_ISGITLINK(ce->ce_mode)) {
1789 struct object_id oid;
1790 int sub_head = resolve_gitlink_ref(ce->name, "HEAD", &oid);
1791 /*
1792 * If we are not going to update the submodule, then
1793 * we don't care.
1794 */
1795 if (!sub_head && oideq(&oid, &ce->oid))
1796 return 0;
1797 return verify_clean_submodule(sub_head ? NULL : oid_to_hex(&oid),
1798 ce, o);
1799 }
1800
1801 /*
1802 * First let's make sure we do not have a local modification
1803 * in that directory.
1804 */
1805 namelen = ce_namelen(ce);
1806 for (i = locate_in_src_index(ce, o);
1807 i < o->src_index->cache_nr;
1808 i++) {
1809 struct cache_entry *ce2 = o->src_index->cache[i];
1810 int len = ce_namelen(ce2);
1811 if (len < namelen ||
1812 strncmp(ce->name, ce2->name, namelen) ||
1813 ce2->name[namelen] != '/')
1814 break;
1815 /*
1816 * ce2->name is an entry in the subdirectory to be
1817 * removed.
1818 */
1819 if (!ce_stage(ce2)) {
1820 if (verify_uptodate(ce2, o))
1821 return -1;
1822 add_entry(o, ce2, CE_REMOVE, 0);
1823 invalidate_ce_path(ce, o);
1824 mark_ce_used(ce2, o);
1825 }
1826 cnt++;
1827 }
1828
1829 /*
1830 * Then we need to make sure that we do not lose a locally
1831 * present file that is not ignored.
1832 */
1833 pathbuf = xstrfmt("%.*s/", namelen, ce->name);
1834
1835 memset(&d, 0, sizeof(d));
1836 if (o->dir)
1837 d.exclude_per_dir = o->dir->exclude_per_dir;
1838 i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL);
1839 if (i)
1840 return add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1841 free(pathbuf);
1842 return cnt;
1843 }
1844
1845 /*
1846 * This gets called when there was no index entry for the tree entry 'dst',
1847 * but we found a file in the working tree that 'lstat()' said was fine,
1848 * and we're on a case-insensitive filesystem.
1849 *
1850 * See if we can find a case-insensitive match in the index that also
1851 * matches the stat information, and assume it's that other file!
1852 */
1853 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1854 {
1855 const struct cache_entry *src;
1856
1857 src = index_file_exists(o->src_index, name, len, 1);
1858 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1859 }
1860
1861 static int check_ok_to_remove(const char *name, int len, int dtype,
1862 const struct cache_entry *ce, struct stat *st,
1863 enum unpack_trees_error_types error_type,
1864 struct unpack_trees_options *o)
1865 {
1866 const struct cache_entry *result;
1867
1868 /*
1869 * It may be that the 'lstat()' succeeded even though
1870 * target 'ce' was absent, because there is an old
1871 * entry that is different only in case..
1872 *
1873 * Ignore that lstat() if it matches.
1874 */
1875 if (ignore_case && icase_exists(o, name, len, st))
1876 return 0;
1877
1878 if (o->dir &&
1879 is_excluded(o->dir, o->src_index, name, &dtype))
1880 /*
1881 * ce->name is explicitly excluded, so it is Ok to
1882 * overwrite it.
1883 */
1884 return 0;
1885 if (S_ISDIR(st->st_mode)) {
1886 /*
1887 * We are checking out path "foo" and
1888 * found "foo/." in the working tree.
1889 * This is tricky -- if we have modified
1890 * files that are in "foo/" we would lose
1891 * them.
1892 */
1893 if (verify_clean_subdirectory(ce, o) < 0)
1894 return -1;
1895 return 0;
1896 }
1897
1898 /*
1899 * The previous round may already have decided to
1900 * delete this path, which is in a subdirectory that
1901 * is being replaced with a blob.
1902 */
1903 result = index_file_exists(&o->result, name, len, 0);
1904 if (result) {
1905 if (result->ce_flags & CE_REMOVE)
1906 return 0;
1907 }
1908
1909 return add_rejected_path(o, error_type, name);
1910 }
1911
1912 /*
1913 * We do not want to remove or overwrite a working tree file that
1914 * is not tracked, unless it is ignored.
1915 */
1916 static int verify_absent_1(const struct cache_entry *ce,
1917 enum unpack_trees_error_types error_type,
1918 struct unpack_trees_options *o)
1919 {
1920 int len;
1921 struct stat st;
1922
1923 if (o->index_only || o->reset || !o->update)
1924 return 0;
1925
1926 len = check_leading_path(ce->name, ce_namelen(ce));
1927 if (!len)
1928 return 0;
1929 else if (len > 0) {
1930 char *path;
1931 int ret;
1932
1933 path = xmemdupz(ce->name, len);
1934 if (lstat(path, &st))
1935 ret = error_errno("cannot stat '%s'", path);
1936 else {
1937 if (submodule_from_ce(ce))
1938 ret = check_submodule_move_head(ce,
1939 oid_to_hex(&ce->oid),
1940 NULL, o);
1941 else
1942 ret = check_ok_to_remove(path, len, DT_UNKNOWN, NULL,
1943 &st, error_type, o);
1944 }
1945 free(path);
1946 return ret;
1947 } else if (lstat(ce->name, &st)) {
1948 if (errno != ENOENT)
1949 return error_errno("cannot stat '%s'", ce->name);
1950 return 0;
1951 } else {
1952 if (submodule_from_ce(ce))
1953 return check_submodule_move_head(ce, oid_to_hex(&ce->oid),
1954 NULL, o);
1955
1956 return check_ok_to_remove(ce->name, ce_namelen(ce),
1957 ce_to_dtype(ce), ce, &st,
1958 error_type, o);
1959 }
1960 }
1961
1962 static int verify_absent(const struct cache_entry *ce,
1963 enum unpack_trees_error_types error_type,
1964 struct unpack_trees_options *o)
1965 {
1966 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1967 return 0;
1968 return verify_absent_1(ce, error_type, o);
1969 }
1970
1971 static int verify_absent_sparse(const struct cache_entry *ce,
1972 enum unpack_trees_error_types error_type,
1973 struct unpack_trees_options *o)
1974 {
1975 enum unpack_trees_error_types orphaned_error = error_type;
1976 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1977 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1978
1979 return verify_absent_1(ce, orphaned_error, o);
1980 }
1981
1982 static int merged_entry(const struct cache_entry *ce,
1983 const struct cache_entry *old,
1984 struct unpack_trees_options *o)
1985 {
1986 int update = CE_UPDATE;
1987 struct cache_entry *merge = dup_cache_entry(ce, &o->result);
1988
1989 if (!old) {
1990 /*
1991 * New index entries. In sparse checkout, the following
1992 * verify_absent() will be delayed until after
1993 * traverse_trees() finishes in unpack_trees(), then:
1994 *
1995 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1996 * - verify_absent() be called again, this time with
1997 * correct CE_NEW_SKIP_WORKTREE
1998 *
1999 * verify_absent() call here does nothing in sparse
2000 * checkout (i.e. o->skip_sparse_checkout == 0)
2001 */
2002 update |= CE_ADDED;
2003 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
2004
2005 if (verify_absent(merge,
2006 ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
2007 discard_cache_entry(merge);
2008 return -1;
2009 }
2010 invalidate_ce_path(merge, o);
2011
2012 if (submodule_from_ce(ce)) {
2013 int ret = check_submodule_move_head(ce, NULL,
2014 oid_to_hex(&ce->oid),
2015 o);
2016 if (ret)
2017 return ret;
2018 }
2019
2020 } else if (!(old->ce_flags & CE_CONFLICTED)) {
2021 /*
2022 * See if we can re-use the old CE directly?
2023 * That way we get the uptodate stat info.
2024 *
2025 * This also removes the UPDATE flag on a match; otherwise
2026 * we will end up overwriting local changes in the work tree.
2027 */
2028 if (same(old, merge)) {
2029 copy_cache_entry(merge, old);
2030 update = 0;
2031 } else {
2032 if (verify_uptodate(old, o)) {
2033 discard_cache_entry(merge);
2034 return -1;
2035 }
2036 /* Migrate old flags over */
2037 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
2038 invalidate_ce_path(old, o);
2039 }
2040
2041 if (submodule_from_ce(ce)) {
2042 int ret = check_submodule_move_head(ce, oid_to_hex(&old->oid),
2043 oid_to_hex(&ce->oid),
2044 o);
2045 if (ret)
2046 return ret;
2047 }
2048 } else {
2049 /*
2050 * Previously unmerged entry left as an existence
2051 * marker by read_index_unmerged();
2052 */
2053 invalidate_ce_path(old, o);
2054 }
2055
2056 do_add_entry(o, merge, update, CE_STAGEMASK);
2057 return 1;
2058 }
2059
2060 static int deleted_entry(const struct cache_entry *ce,
2061 const struct cache_entry *old,
2062 struct unpack_trees_options *o)
2063 {
2064 /* Did it exist in the index? */
2065 if (!old) {
2066 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2067 return -1;
2068 return 0;
2069 }
2070 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
2071 return -1;
2072 add_entry(o, ce, CE_REMOVE, 0);
2073 invalidate_ce_path(ce, o);
2074 return 1;
2075 }
2076
2077 static int keep_entry(const struct cache_entry *ce,
2078 struct unpack_trees_options *o)
2079 {
2080 add_entry(o, ce, 0, 0);
2081 if (ce_stage(ce))
2082 invalidate_ce_path(ce, o);
2083 return 1;
2084 }
2085
2086 #if DBRT_DEBUG
2087 static void show_stage_entry(FILE *o,
2088 const char *label, const struct cache_entry *ce)
2089 {
2090 if (!ce)
2091 fprintf(o, "%s (missing)\n", label);
2092 else
2093 fprintf(o, "%s%06o %s %d\t%s\n",
2094 label,
2095 ce->ce_mode,
2096 oid_to_hex(&ce->oid),
2097 ce_stage(ce),
2098 ce->name);
2099 }
2100 #endif
2101
2102 int threeway_merge(const struct cache_entry * const *stages,
2103 struct unpack_trees_options *o)
2104 {
2105 const struct cache_entry *index;
2106 const struct cache_entry *head;
2107 const struct cache_entry *remote = stages[o->head_idx + 1];
2108 int count;
2109 int head_match = 0;
2110 int remote_match = 0;
2111
2112 int df_conflict_head = 0;
2113 int df_conflict_remote = 0;
2114
2115 int any_anc_missing = 0;
2116 int no_anc_exists = 1;
2117 int i;
2118
2119 for (i = 1; i < o->head_idx; i++) {
2120 if (!stages[i] || stages[i] == o->df_conflict_entry)
2121 any_anc_missing = 1;
2122 else
2123 no_anc_exists = 0;
2124 }
2125
2126 index = stages[0];
2127 head = stages[o->head_idx];
2128
2129 if (head == o->df_conflict_entry) {
2130 df_conflict_head = 1;
2131 head = NULL;
2132 }
2133
2134 if (remote == o->df_conflict_entry) {
2135 df_conflict_remote = 1;
2136 remote = NULL;
2137 }
2138
2139 /*
2140 * First, if there's a #16 situation, note that to prevent #13
2141 * and #14.
2142 */
2143 if (!same(remote, head)) {
2144 for (i = 1; i < o->head_idx; i++) {
2145 if (same(stages[i], head)) {
2146 head_match = i;
2147 }
2148 if (same(stages[i], remote)) {
2149 remote_match = i;
2150 }
2151 }
2152 }
2153
2154 /*
2155 * We start with cases where the index is allowed to match
2156 * something other than the head: #14(ALT) and #2ALT, where it
2157 * is permitted to match the result instead.
2158 */
2159 /* #14, #14ALT, #2ALT */
2160 if (remote && !df_conflict_head && head_match && !remote_match) {
2161 if (index && !same(index, remote) && !same(index, head))
2162 return reject_merge(index, o);
2163 return merged_entry(remote, index, o);
2164 }
2165 /*
2166 * If we have an entry in the index cache, then we want to
2167 * make sure that it matches head.
2168 */
2169 if (index && !same(index, head))
2170 return reject_merge(index, o);
2171
2172 if (head) {
2173 /* #5ALT, #15 */
2174 if (same(head, remote))
2175 return merged_entry(head, index, o);
2176 /* #13, #3ALT */
2177 if (!df_conflict_remote && remote_match && !head_match)
2178 return merged_entry(head, index, o);
2179 }
2180
2181 /* #1 */
2182 if (!head && !remote && any_anc_missing)
2183 return 0;
2184
2185 /*
2186 * Under the "aggressive" rule, we resolve mostly trivial
2187 * cases that we historically had git-merge-one-file resolve.
2188 */
2189 if (o->aggressive) {
2190 int head_deleted = !head;
2191 int remote_deleted = !remote;
2192 const struct cache_entry *ce = NULL;
2193
2194 if (index)
2195 ce = index;
2196 else if (head)
2197 ce = head;
2198 else if (remote)
2199 ce = remote;
2200 else {
2201 for (i = 1; i < o->head_idx; i++) {
2202 if (stages[i] && stages[i] != o->df_conflict_entry) {
2203 ce = stages[i];
2204 break;
2205 }
2206 }
2207 }
2208
2209 /*
2210 * Deleted in both.
2211 * Deleted in one and unchanged in the other.
2212 */
2213 if ((head_deleted && remote_deleted) ||
2214 (head_deleted && remote && remote_match) ||
2215 (remote_deleted && head && head_match)) {
2216 if (index)
2217 return deleted_entry(index, index, o);
2218 if (ce && !head_deleted) {
2219 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2220 return -1;
2221 }
2222 return 0;
2223 }
2224 /*
2225 * Added in both, identically.
2226 */
2227 if (no_anc_exists && head && remote && same(head, remote))
2228 return merged_entry(head, index, o);
2229
2230 }
2231
2232 /* Below are "no merge" cases, which require that the index be
2233 * up-to-date to avoid the files getting overwritten with
2234 * conflict resolution files.
2235 */
2236 if (index) {
2237 if (verify_uptodate(index, o))
2238 return -1;
2239 }
2240
2241 o->nontrivial_merge = 1;
2242
2243 /* #2, #3, #4, #6, #7, #9, #10, #11. */
2244 count = 0;
2245 if (!head_match || !remote_match) {
2246 for (i = 1; i < o->head_idx; i++) {
2247 if (stages[i] && stages[i] != o->df_conflict_entry) {
2248 keep_entry(stages[i], o);
2249 count++;
2250 break;
2251 }
2252 }
2253 }
2254 #if DBRT_DEBUG
2255 else {
2256 fprintf(stderr, "read-tree: warning #16 detected\n");
2257 show_stage_entry(stderr, "head ", stages[head_match]);
2258 show_stage_entry(stderr, "remote ", stages[remote_match]);
2259 }
2260 #endif
2261 if (head) { count += keep_entry(head, o); }
2262 if (remote) { count += keep_entry(remote, o); }
2263 return count;
2264 }
2265
2266 /*
2267 * Two-way merge.
2268 *
2269 * The rule is to "carry forward" what is in the index without losing
2270 * information across a "fast-forward", favoring a successful merge
2271 * over a merge failure when it makes sense. For details of the
2272 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
2273 *
2274 */
2275 int twoway_merge(const struct cache_entry * const *src,
2276 struct unpack_trees_options *o)
2277 {
2278 const struct cache_entry *current = src[0];
2279 const struct cache_entry *oldtree = src[1];
2280 const struct cache_entry *newtree = src[2];
2281
2282 if (o->merge_size != 2)
2283 return error("Cannot do a twoway merge of %d trees",
2284 o->merge_size);
2285
2286 if (oldtree == o->df_conflict_entry)
2287 oldtree = NULL;
2288 if (newtree == o->df_conflict_entry)
2289 newtree = NULL;
2290
2291 if (current) {
2292 if (current->ce_flags & CE_CONFLICTED) {
2293 if (same(oldtree, newtree) || o->reset) {
2294 if (!newtree)
2295 return deleted_entry(current, current, o);
2296 else
2297 return merged_entry(newtree, current, o);
2298 }
2299 return reject_merge(current, o);
2300 } else if ((!oldtree && !newtree) || /* 4 and 5 */
2301 (!oldtree && newtree &&
2302 same(current, newtree)) || /* 6 and 7 */
2303 (oldtree && newtree &&
2304 same(oldtree, newtree)) || /* 14 and 15 */
2305 (oldtree && newtree &&
2306 !same(oldtree, newtree) && /* 18 and 19 */
2307 same(current, newtree))) {
2308 return keep_entry(current, o);
2309 } else if (oldtree && !newtree && same(current, oldtree)) {
2310 /* 10 or 11 */
2311 return deleted_entry(oldtree, current, o);
2312 } else if (oldtree && newtree &&
2313 same(current, oldtree) && !same(current, newtree)) {
2314 /* 20 or 21 */
2315 return merged_entry(newtree, current, o);
2316 } else
2317 return reject_merge(current, o);
2318 }
2319 else if (newtree) {
2320 if (oldtree && !o->initial_checkout) {
2321 /*
2322 * deletion of the path was staged;
2323 */
2324 if (same(oldtree, newtree))
2325 return 1;
2326 return reject_merge(oldtree, o);
2327 }
2328 return merged_entry(newtree, current, o);
2329 }
2330 return deleted_entry(oldtree, current, o);
2331 }
2332
2333 /*
2334 * Bind merge.
2335 *
2336 * Keep the index entries at stage0, collapse stage1 but make sure
2337 * stage0 does not have anything there.
2338 */
2339 int bind_merge(const struct cache_entry * const *src,
2340 struct unpack_trees_options *o)
2341 {
2342 const struct cache_entry *old = src[0];
2343 const struct cache_entry *a = src[1];
2344
2345 if (o->merge_size != 1)
2346 return error("Cannot do a bind merge of %d trees",
2347 o->merge_size);
2348 if (a && old)
2349 return o->quiet ? -1 :
2350 error(ERRORMSG(o, ERROR_BIND_OVERLAP),
2351 super_prefixed(a->name),
2352 super_prefixed(old->name));
2353 if (!a)
2354 return keep_entry(old, o);
2355 else
2356 return merged_entry(a, NULL, o);
2357 }
2358
2359 /*
2360 * One-way merge.
2361 *
2362 * The rule is:
2363 * - take the stat information from stage0, take the data from stage1
2364 */
2365 int oneway_merge(const struct cache_entry * const *src,
2366 struct unpack_trees_options *o)
2367 {
2368 const struct cache_entry *old = src[0];
2369 const struct cache_entry *a = src[1];
2370
2371 if (o->merge_size != 1)
2372 return error("Cannot do a oneway merge of %d trees",
2373 o->merge_size);
2374
2375 if (!a || a == o->df_conflict_entry)
2376 return deleted_entry(old, old, o);
2377
2378 if (old && same(old, a)) {
2379 int update = 0;
2380 if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
2381 struct stat st;
2382 if (lstat(old->name, &st) ||
2383 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
2384 update |= CE_UPDATE;
2385 }
2386 if (o->update && S_ISGITLINK(old->ce_mode) &&
2387 should_update_submodules() && !verify_uptodate(old, o))
2388 update |= CE_UPDATE;
2389 add_entry(o, old, update, CE_STAGEMASK);
2390 return 0;
2391 }
2392 return merged_entry(a, old, o);
2393 }