492eff666a7979568202247c4306578223fe7eab
[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 size_t len = traverse_path_len(info, tree_entry_len(names));
690 char *name = xmalloc(len + 1 /* slash */ + 1 /* NUL */);
691 int pos;
692
693 make_traverse_path(name, info, names->path, names->pathlen);
694 name[len++] = '/';
695 name[len] = '\0';
696 pos = index_name_pos(o->src_index, name, len);
697 if (pos >= 0)
698 BUG("This is a directory and should not exist in index");
699 pos = -pos - 1;
700 if (!starts_with(o->src_index->cache[pos]->name, name) ||
701 (pos > 0 && starts_with(o->src_index->cache[pos-1]->name, name)))
702 BUG("pos must point at the first entry in this directory");
703 free(name);
704 return pos;
705 }
706
707 /*
708 * Fast path if we detect that all trees are the same as cache-tree at this
709 * path. We'll walk these trees in an iterative loop using cache-tree/index
710 * instead of ODB since we already know what these trees contain.
711 */
712 static int traverse_by_cache_tree(int pos, int nr_entries, int nr_names,
713 struct traverse_info *info)
714 {
715 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
716 struct unpack_trees_options *o = info->data;
717 struct cache_entry *tree_ce = NULL;
718 int ce_len = 0;
719 int i, d;
720
721 if (!o->merge)
722 BUG("We need cache-tree to do this optimization");
723
724 /*
725 * Do what unpack_callback() and unpack_nondirectories() normally
726 * do. But we walk all paths in an iterative loop instead.
727 *
728 * D/F conflicts and higher stage entries are not a concern
729 * because cache-tree would be invalidated and we would never
730 * get here in the first place.
731 */
732 for (i = 0; i < nr_entries; i++) {
733 int new_ce_len, len, rc;
734
735 src[0] = o->src_index->cache[pos + i];
736
737 len = ce_namelen(src[0]);
738 new_ce_len = cache_entry_size(len);
739
740 if (new_ce_len > ce_len) {
741 new_ce_len <<= 1;
742 tree_ce = xrealloc(tree_ce, new_ce_len);
743 memset(tree_ce, 0, new_ce_len);
744 ce_len = new_ce_len;
745
746 tree_ce->ce_flags = create_ce_flags(0);
747
748 for (d = 1; d <= nr_names; d++)
749 src[d] = tree_ce;
750 }
751
752 tree_ce->ce_mode = src[0]->ce_mode;
753 tree_ce->ce_namelen = len;
754 oidcpy(&tree_ce->oid, &src[0]->oid);
755 memcpy(tree_ce->name, src[0]->name, len + 1);
756
757 rc = call_unpack_fn((const struct cache_entry * const *)src, o);
758 if (rc < 0) {
759 free(tree_ce);
760 return rc;
761 }
762
763 mark_ce_used(src[0], o);
764 }
765 free(tree_ce);
766 if (o->debug_unpack)
767 printf("Unpacked %d entries from %s to %s using cache-tree\n",
768 nr_entries,
769 o->src_index->cache[pos]->name,
770 o->src_index->cache[pos + nr_entries - 1]->name);
771 return 0;
772 }
773
774 static int traverse_trees_recursive(int n, unsigned long dirmask,
775 unsigned long df_conflicts,
776 struct name_entry *names,
777 struct traverse_info *info)
778 {
779 struct unpack_trees_options *o = info->data;
780 int i, ret, bottom;
781 int nr_buf = 0;
782 struct tree_desc t[MAX_UNPACK_TREES];
783 void *buf[MAX_UNPACK_TREES];
784 struct traverse_info newinfo;
785 struct name_entry *p;
786 int nr_entries;
787
788 nr_entries = all_trees_same_as_cache_tree(n, dirmask, names, info);
789 if (nr_entries > 0) {
790 int pos = index_pos_by_traverse_info(names, info);
791
792 if (!o->merge || df_conflicts)
793 BUG("Wrong condition to get here buddy");
794
795 /*
796 * All entries up to 'pos' must have been processed
797 * (i.e. marked CE_UNPACKED) at this point. But to be safe,
798 * save and restore cache_bottom anyway to not miss
799 * unprocessed entries before 'pos'.
800 */
801 bottom = o->cache_bottom;
802 ret = traverse_by_cache_tree(pos, nr_entries, n, info);
803 o->cache_bottom = bottom;
804 return ret;
805 }
806
807 p = names;
808 while (!p->mode)
809 p++;
810
811 newinfo = *info;
812 newinfo.prev = info;
813 newinfo.pathspec = info->pathspec;
814 newinfo.name = p->path;
815 newinfo.namelen = p->pathlen;
816 newinfo.mode = p->mode;
817 newinfo.pathlen = st_add3(newinfo.pathlen, tree_entry_len(p), 1);
818 newinfo.df_conflicts |= df_conflicts;
819
820 /*
821 * Fetch the tree from the ODB for each peer directory in the
822 * n commits.
823 *
824 * For 2- and 3-way traversals, we try to avoid hitting the
825 * ODB twice for the same OID. This should yield a nice speed
826 * up in checkouts and merges when the commits are similar.
827 *
828 * We don't bother doing the full O(n^2) search for larger n,
829 * because wider traversals don't happen that often and we
830 * avoid the search setup.
831 *
832 * When 2 peer OIDs are the same, we just copy the tree
833 * descriptor data. This implicitly borrows the buffer
834 * data from the earlier cell.
835 */
836 for (i = 0; i < n; i++, dirmask >>= 1) {
837 if (i > 0 && are_same_oid(&names[i], &names[i - 1]))
838 t[i] = t[i - 1];
839 else if (i > 1 && are_same_oid(&names[i], &names[i - 2]))
840 t[i] = t[i - 2];
841 else {
842 const struct object_id *oid = NULL;
843 if (dirmask & 1)
844 oid = &names[i].oid;
845 buf[nr_buf++] = fill_tree_descriptor(t + i, oid);
846 }
847 }
848
849 bottom = switch_cache_bottom(&newinfo);
850 ret = traverse_trees(o->src_index, n, t, &newinfo);
851 restore_cache_bottom(&newinfo, bottom);
852
853 for (i = 0; i < nr_buf; i++)
854 free(buf[i]);
855
856 return ret;
857 }
858
859 /*
860 * Compare the traverse-path to the cache entry without actually
861 * having to generate the textual representation of the traverse
862 * path.
863 *
864 * NOTE! This *only* compares up to the size of the traverse path
865 * itself - the caller needs to do the final check for the cache
866 * entry having more data at the end!
867 */
868 static int do_compare_entry_piecewise(const struct cache_entry *ce,
869 const struct traverse_info *info,
870 const char *name, size_t namelen,
871 unsigned mode)
872 {
873 int pathlen, ce_len;
874 const char *ce_name;
875
876 if (info->prev) {
877 int cmp = do_compare_entry_piecewise(ce, info->prev,
878 info->name, info->namelen,
879 info->mode);
880 if (cmp)
881 return cmp;
882 }
883 pathlen = info->pathlen;
884 ce_len = ce_namelen(ce);
885
886 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
887 if (ce_len < pathlen)
888 return -1;
889
890 ce_len -= pathlen;
891 ce_name = ce->name + pathlen;
892
893 return df_name_compare(ce_name, ce_len, S_IFREG, name, namelen, mode);
894 }
895
896 static int do_compare_entry(const struct cache_entry *ce,
897 const struct traverse_info *info,
898 const char *name, size_t namelen,
899 unsigned mode)
900 {
901 int pathlen, ce_len;
902 const char *ce_name;
903 int cmp;
904
905 /*
906 * If we have not precomputed the traverse path, it is quicker
907 * to avoid doing so. But if we have precomputed it,
908 * it is quicker to use the precomputed version.
909 */
910 if (!info->traverse_path)
911 return do_compare_entry_piecewise(ce, info, name, namelen, mode);
912
913 cmp = strncmp(ce->name, info->traverse_path, info->pathlen);
914 if (cmp)
915 return cmp;
916
917 pathlen = info->pathlen;
918 ce_len = ce_namelen(ce);
919
920 if (ce_len < pathlen)
921 return -1;
922
923 ce_len -= pathlen;
924 ce_name = ce->name + pathlen;
925
926 return df_name_compare(ce_name, ce_len, S_IFREG, name, namelen, mode);
927 }
928
929 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
930 {
931 int cmp = do_compare_entry(ce, info, n->path, n->pathlen, n->mode);
932 if (cmp)
933 return cmp;
934
935 /*
936 * Even if the beginning compared identically, the ce should
937 * compare as bigger than a directory leading up to it!
938 */
939 return ce_namelen(ce) > traverse_path_len(info, tree_entry_len(n));
940 }
941
942 static int ce_in_traverse_path(const struct cache_entry *ce,
943 const struct traverse_info *info)
944 {
945 if (!info->prev)
946 return 1;
947 if (do_compare_entry(ce, info->prev,
948 info->name, info->namelen, info->mode))
949 return 0;
950 /*
951 * If ce (blob) is the same name as the path (which is a tree
952 * we will be descending into), it won't be inside it.
953 */
954 return (info->pathlen < ce_namelen(ce));
955 }
956
957 static struct cache_entry *create_ce_entry(const struct traverse_info *info,
958 const struct name_entry *n,
959 int stage,
960 struct index_state *istate,
961 int is_transient)
962 {
963 size_t len = traverse_path_len(info, tree_entry_len(n));
964 struct cache_entry *ce =
965 is_transient ?
966 make_empty_transient_cache_entry(len) :
967 make_empty_cache_entry(istate, len);
968
969 ce->ce_mode = create_ce_mode(n->mode);
970 ce->ce_flags = create_ce_flags(stage);
971 ce->ce_namelen = len;
972 oidcpy(&ce->oid, &n->oid);
973 make_traverse_path(ce->name, info, n->path, n->pathlen);
974
975 return ce;
976 }
977
978 /*
979 * Note that traverse_by_cache_tree() duplicates some logic in this function
980 * without actually calling it. If you change the logic here you may need to
981 * check and change there as well.
982 */
983 static int unpack_nondirectories(int n, unsigned long mask,
984 unsigned long dirmask,
985 struct cache_entry **src,
986 const struct name_entry *names,
987 const struct traverse_info *info)
988 {
989 int i;
990 struct unpack_trees_options *o = info->data;
991 unsigned long conflicts = info->df_conflicts | dirmask;
992
993 /* Do we have *only* directories? Nothing to do */
994 if (mask == dirmask && !src[0])
995 return 0;
996
997 /*
998 * Ok, we've filled in up to any potential index entry in src[0],
999 * now do the rest.
1000 */
1001 for (i = 0; i < n; i++) {
1002 int stage;
1003 unsigned int bit = 1ul << i;
1004 if (conflicts & bit) {
1005 src[i + o->merge] = o->df_conflict_entry;
1006 continue;
1007 }
1008 if (!(mask & bit))
1009 continue;
1010 if (!o->merge)
1011 stage = 0;
1012 else if (i + 1 < o->head_idx)
1013 stage = 1;
1014 else if (i + 1 > o->head_idx)
1015 stage = 3;
1016 else
1017 stage = 2;
1018
1019 /*
1020 * If the merge bit is set, then the cache entries are
1021 * discarded in the following block. In this case,
1022 * construct "transient" cache_entries, as they are
1023 * not stored in the index. otherwise construct the
1024 * cache entry from the index aware logic.
1025 */
1026 src[i + o->merge] = create_ce_entry(info, names + i, stage, &o->result, o->merge);
1027 }
1028
1029 if (o->merge) {
1030 int rc = call_unpack_fn((const struct cache_entry * const *)src,
1031 o);
1032 for (i = 0; i < n; i++) {
1033 struct cache_entry *ce = src[i + o->merge];
1034 if (ce != o->df_conflict_entry)
1035 discard_cache_entry(ce);
1036 }
1037 return rc;
1038 }
1039
1040 for (i = 0; i < n; i++)
1041 if (src[i] && src[i] != o->df_conflict_entry)
1042 if (do_add_entry(o, src[i], 0, 0))
1043 return -1;
1044
1045 return 0;
1046 }
1047
1048 static int unpack_failed(struct unpack_trees_options *o, const char *message)
1049 {
1050 discard_index(&o->result);
1051 if (!o->quiet && !o->exiting_early) {
1052 if (message)
1053 return error("%s", message);
1054 return -1;
1055 }
1056 return -1;
1057 }
1058
1059 /*
1060 * The tree traversal is looking at name p. If we have a matching entry,
1061 * return it. If name p is a directory in the index, do not return
1062 * anything, as we will want to match it when the traversal descends into
1063 * the directory.
1064 */
1065 static int find_cache_pos(struct traverse_info *info,
1066 const char *p, size_t p_len)
1067 {
1068 int pos;
1069 struct unpack_trees_options *o = info->data;
1070 struct index_state *index = o->src_index;
1071 int pfxlen = info->pathlen;
1072
1073 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
1074 const struct cache_entry *ce = index->cache[pos];
1075 const char *ce_name, *ce_slash;
1076 int cmp, ce_len;
1077
1078 if (ce->ce_flags & CE_UNPACKED) {
1079 /*
1080 * cache_bottom entry is already unpacked, so
1081 * we can never match it; don't check it
1082 * again.
1083 */
1084 if (pos == o->cache_bottom)
1085 ++o->cache_bottom;
1086 continue;
1087 }
1088 if (!ce_in_traverse_path(ce, info)) {
1089 /*
1090 * Check if we can skip future cache checks
1091 * (because we're already past all possible
1092 * entries in the traverse path).
1093 */
1094 if (info->traverse_path) {
1095 if (strncmp(ce->name, info->traverse_path,
1096 info->pathlen) > 0)
1097 break;
1098 }
1099 continue;
1100 }
1101 ce_name = ce->name + pfxlen;
1102 ce_slash = strchr(ce_name, '/');
1103 if (ce_slash)
1104 ce_len = ce_slash - ce_name;
1105 else
1106 ce_len = ce_namelen(ce) - pfxlen;
1107 cmp = name_compare(p, p_len, ce_name, ce_len);
1108 /*
1109 * Exact match; if we have a directory we need to
1110 * delay returning it.
1111 */
1112 if (!cmp)
1113 return ce_slash ? -2 - pos : pos;
1114 if (0 < cmp)
1115 continue; /* keep looking */
1116 /*
1117 * ce_name sorts after p->path; could it be that we
1118 * have files under p->path directory in the index?
1119 * E.g. ce_name == "t-i", and p->path == "t"; we may
1120 * have "t/a" in the index.
1121 */
1122 if (p_len < ce_len && !memcmp(ce_name, p, p_len) &&
1123 ce_name[p_len] < '/')
1124 continue; /* keep looking */
1125 break;
1126 }
1127 return -1;
1128 }
1129
1130 static struct cache_entry *find_cache_entry(struct traverse_info *info,
1131 const struct name_entry *p)
1132 {
1133 int pos = find_cache_pos(info, p->path, p->pathlen);
1134 struct unpack_trees_options *o = info->data;
1135
1136 if (0 <= pos)
1137 return o->src_index->cache[pos];
1138 else
1139 return NULL;
1140 }
1141
1142 static void debug_path(struct traverse_info *info)
1143 {
1144 if (info->prev) {
1145 debug_path(info->prev);
1146 if (*info->prev->name)
1147 putchar('/');
1148 }
1149 printf("%s", info->name);
1150 }
1151
1152 static void debug_name_entry(int i, struct name_entry *n)
1153 {
1154 printf("ent#%d %06o %s\n", i,
1155 n->path ? n->mode : 0,
1156 n->path ? n->path : "(missing)");
1157 }
1158
1159 static void debug_unpack_callback(int n,
1160 unsigned long mask,
1161 unsigned long dirmask,
1162 struct name_entry *names,
1163 struct traverse_info *info)
1164 {
1165 int i;
1166 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
1167 mask, dirmask, n);
1168 debug_path(info);
1169 putchar('\n');
1170 for (i = 0; i < n; i++)
1171 debug_name_entry(i, names + i);
1172 }
1173
1174 /*
1175 * Note that traverse_by_cache_tree() duplicates some logic in this function
1176 * without actually calling it. If you change the logic here you may need to
1177 * check and change there as well.
1178 */
1179 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
1180 {
1181 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
1182 struct unpack_trees_options *o = info->data;
1183 const struct name_entry *p = names;
1184
1185 /* Find first entry with a real name (we could use "mask" too) */
1186 while (!p->mode)
1187 p++;
1188
1189 if (o->debug_unpack)
1190 debug_unpack_callback(n, mask, dirmask, names, info);
1191
1192 /* Are we supposed to look at the index too? */
1193 if (o->merge) {
1194 while (1) {
1195 int cmp;
1196 struct cache_entry *ce;
1197
1198 if (o->diff_index_cached)
1199 ce = next_cache_entry(o);
1200 else
1201 ce = find_cache_entry(info, p);
1202
1203 if (!ce)
1204 break;
1205 cmp = compare_entry(ce, info, p);
1206 if (cmp < 0) {
1207 if (unpack_index_entry(ce, o) < 0)
1208 return unpack_failed(o, NULL);
1209 continue;
1210 }
1211 if (!cmp) {
1212 if (ce_stage(ce)) {
1213 /*
1214 * If we skip unmerged index
1215 * entries, we'll skip this
1216 * entry *and* the tree
1217 * entries associated with it!
1218 */
1219 if (o->skip_unmerged) {
1220 add_same_unmerged(ce, o);
1221 return mask;
1222 }
1223 }
1224 src[0] = ce;
1225 }
1226 break;
1227 }
1228 }
1229
1230 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
1231 return -1;
1232
1233 if (o->merge && src[0]) {
1234 if (ce_stage(src[0]))
1235 mark_ce_used_same_name(src[0], o);
1236 else
1237 mark_ce_used(src[0], o);
1238 }
1239
1240 /* Now handle any directories.. */
1241 if (dirmask) {
1242 /* special case: "diff-index --cached" looking at a tree */
1243 if (o->diff_index_cached &&
1244 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
1245 int matches;
1246 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
1247 names, info);
1248 /*
1249 * Everything under the name matches; skip the
1250 * entire hierarchy. diff_index_cached codepath
1251 * special cases D/F conflicts in such a way that
1252 * it does not do any look-ahead, so this is safe.
1253 */
1254 if (matches) {
1255 o->cache_bottom += matches;
1256 return mask;
1257 }
1258 }
1259
1260 if (traverse_trees_recursive(n, dirmask, mask & ~dirmask,
1261 names, info) < 0)
1262 return -1;
1263 return mask;
1264 }
1265
1266 return mask;
1267 }
1268
1269 static int clear_ce_flags_1(struct index_state *istate,
1270 struct cache_entry **cache, int nr,
1271 struct strbuf *prefix,
1272 int select_mask, int clear_mask,
1273 struct exclude_list *el, int defval);
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 exclude_list *el, int defval)
1282 {
1283 struct cache_entry **cache_end;
1284 int dtype = DT_DIR;
1285 int ret = is_excluded_from_list(prefix->buf, prefix->len,
1286 basename, &dtype, el, istate);
1287 int rc;
1288
1289 strbuf_addch(prefix, '/');
1290
1291 /* If undecided, use matching result of parent dir in defval */
1292 if (ret < 0)
1293 ret = defval;
1294
1295 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
1296 struct cache_entry *ce = *cache_end;
1297 if (strncmp(ce->name, prefix->buf, prefix->len))
1298 break;
1299 }
1300
1301 /*
1302 * TODO: check el, if there are no patterns that may conflict
1303 * with ret (iow, we know in advance the incl/excl
1304 * decision for the entire directory), clear flag here without
1305 * calling clear_ce_flags_1(). That function will call
1306 * the expensive is_excluded_from_list() on every entry.
1307 */
1308 rc = clear_ce_flags_1(istate, cache, cache_end - cache,
1309 prefix,
1310 select_mask, clear_mask,
1311 el, ret);
1312 strbuf_setlen(prefix, prefix->len - 1);
1313 return rc;
1314 }
1315
1316 /*
1317 * Traverse the index, find every entry that matches according to
1318 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
1319 * number of traversed entries.
1320 *
1321 * If select_mask is non-zero, only entries whose ce_flags has on of
1322 * those bits enabled are traversed.
1323 *
1324 * cache : pointer to an index entry
1325 * prefix_len : an offset to its path
1326 *
1327 * The current path ("prefix") including the trailing '/' is
1328 * cache[0]->name[0..(prefix_len-1)]
1329 * Top level path has prefix_len zero.
1330 */
1331 static int clear_ce_flags_1(struct index_state *istate,
1332 struct cache_entry **cache, int nr,
1333 struct strbuf *prefix,
1334 int select_mask, int clear_mask,
1335 struct exclude_list *el, int defval)
1336 {
1337 struct cache_entry **cache_end = cache + nr;
1338
1339 /*
1340 * Process all entries that have the given prefix and meet
1341 * select_mask condition
1342 */
1343 while(cache != cache_end) {
1344 struct cache_entry *ce = *cache;
1345 const char *name, *slash;
1346 int len, dtype, ret;
1347
1348 if (select_mask && !(ce->ce_flags & select_mask)) {
1349 cache++;
1350 continue;
1351 }
1352
1353 if (prefix->len && strncmp(ce->name, prefix->buf, prefix->len))
1354 break;
1355
1356 name = ce->name + prefix->len;
1357 slash = strchr(name, '/');
1358
1359 /* If it's a directory, try whole directory match first */
1360 if (slash) {
1361 int processed;
1362
1363 len = slash - name;
1364 strbuf_add(prefix, name, len);
1365
1366 processed = clear_ce_flags_dir(istate, cache, cache_end - cache,
1367 prefix,
1368 prefix->buf + prefix->len - len,
1369 select_mask, clear_mask,
1370 el, defval);
1371
1372 /* clear_c_f_dir eats a whole dir already? */
1373 if (processed) {
1374 cache += processed;
1375 strbuf_setlen(prefix, prefix->len - len);
1376 continue;
1377 }
1378
1379 strbuf_addch(prefix, '/');
1380 cache += clear_ce_flags_1(istate, cache, cache_end - cache,
1381 prefix,
1382 select_mask, clear_mask, el, defval);
1383 strbuf_setlen(prefix, prefix->len - len - 1);
1384 continue;
1385 }
1386
1387 /* Non-directory */
1388 dtype = ce_to_dtype(ce);
1389 ret = is_excluded_from_list(ce->name, ce_namelen(ce),
1390 name, &dtype, el, istate);
1391 if (ret < 0)
1392 ret = defval;
1393 if (ret > 0)
1394 ce->ce_flags &= ~clear_mask;
1395 cache++;
1396 }
1397 return nr - (cache_end - cache);
1398 }
1399
1400 static int clear_ce_flags(struct index_state *istate,
1401 int select_mask, int clear_mask,
1402 struct exclude_list *el)
1403 {
1404 static struct strbuf prefix = STRBUF_INIT;
1405
1406 strbuf_reset(&prefix);
1407
1408 return clear_ce_flags_1(istate,
1409 istate->cache,
1410 istate->cache_nr,
1411 &prefix,
1412 select_mask, clear_mask,
1413 el, 0);
1414 }
1415
1416 /*
1417 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
1418 */
1419 static void mark_new_skip_worktree(struct exclude_list *el,
1420 struct index_state *istate,
1421 int select_flag, int skip_wt_flag)
1422 {
1423 int i;
1424
1425 /*
1426 * 1. Pretend the narrowest worktree: only unmerged entries
1427 * are checked out
1428 */
1429 for (i = 0; i < istate->cache_nr; i++) {
1430 struct cache_entry *ce = istate->cache[i];
1431
1432 if (select_flag && !(ce->ce_flags & select_flag))
1433 continue;
1434
1435 if (!ce_stage(ce) && !(ce->ce_flags & CE_CONFLICTED))
1436 ce->ce_flags |= skip_wt_flag;
1437 else
1438 ce->ce_flags &= ~skip_wt_flag;
1439 }
1440
1441 /*
1442 * 2. Widen worktree according to sparse-checkout file.
1443 * Matched entries will have skip_wt_flag cleared (i.e. "in")
1444 */
1445 clear_ce_flags(istate, select_flag, skip_wt_flag, el);
1446 }
1447
1448 static int verify_absent(const struct cache_entry *,
1449 enum unpack_trees_error_types,
1450 struct unpack_trees_options *);
1451 /*
1452 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
1453 * resulting index, -2 on failure to reflect the changes to the work tree.
1454 *
1455 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
1456 */
1457 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
1458 {
1459 int i, ret;
1460 static struct cache_entry *dfc;
1461 struct exclude_list el;
1462
1463 if (len > MAX_UNPACK_TREES)
1464 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1465
1466 trace_performance_enter();
1467 memset(&el, 0, sizeof(el));
1468 if (!core_apply_sparse_checkout || !o->update)
1469 o->skip_sparse_checkout = 1;
1470 if (!o->skip_sparse_checkout) {
1471 char *sparse = git_pathdup("info/sparse-checkout");
1472 if (add_excludes_from_file_to_list(sparse, "", 0, &el, NULL) < 0)
1473 o->skip_sparse_checkout = 1;
1474 else
1475 o->el = &el;
1476 free(sparse);
1477 }
1478
1479 memset(&o->result, 0, sizeof(o->result));
1480 o->result.initialized = 1;
1481 o->result.timestamp.sec = o->src_index->timestamp.sec;
1482 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1483 o->result.version = o->src_index->version;
1484 if (!o->src_index->split_index) {
1485 o->result.split_index = NULL;
1486 } else if (o->src_index == o->dst_index) {
1487 /*
1488 * o->dst_index (and thus o->src_index) will be discarded
1489 * and overwritten with o->result at the end of this function,
1490 * so just use src_index's split_index to avoid having to
1491 * create a new one.
1492 */
1493 o->result.split_index = o->src_index->split_index;
1494 o->result.split_index->refcount++;
1495 } else {
1496 o->result.split_index = init_split_index(&o->result);
1497 }
1498 oidcpy(&o->result.oid, &o->src_index->oid);
1499 o->merge_size = len;
1500 mark_all_ce_unused(o->src_index);
1501
1502 /*
1503 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1504 */
1505 if (!o->skip_sparse_checkout)
1506 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1507
1508 if (!dfc)
1509 dfc = xcalloc(1, cache_entry_size(0));
1510 o->df_conflict_entry = dfc;
1511
1512 if (len) {
1513 const char *prefix = o->prefix ? o->prefix : "";
1514 struct traverse_info info;
1515
1516 setup_traverse_info(&info, prefix);
1517 info.fn = unpack_callback;
1518 info.data = o;
1519 info.show_all_errors = o->show_all_errors;
1520 info.pathspec = o->pathspec;
1521
1522 if (o->prefix) {
1523 /*
1524 * Unpack existing index entries that sort before the
1525 * prefix the tree is spliced into. Note that o->merge
1526 * is always true in this case.
1527 */
1528 while (1) {
1529 struct cache_entry *ce = next_cache_entry(o);
1530 if (!ce)
1531 break;
1532 if (ce_in_traverse_path(ce, &info))
1533 break;
1534 if (unpack_index_entry(ce, o) < 0)
1535 goto return_failed;
1536 }
1537 }
1538
1539 trace_performance_enter();
1540 ret = traverse_trees(o->src_index, len, t, &info);
1541 trace_performance_leave("traverse_trees");
1542 if (ret < 0)
1543 goto return_failed;
1544 }
1545
1546 /* Any left-over entries in the index? */
1547 if (o->merge) {
1548 while (1) {
1549 struct cache_entry *ce = next_cache_entry(o);
1550 if (!ce)
1551 break;
1552 if (unpack_index_entry(ce, o) < 0)
1553 goto return_failed;
1554 }
1555 }
1556 mark_all_ce_unused(o->src_index);
1557
1558 if (o->trivial_merges_only && o->nontrivial_merge) {
1559 ret = unpack_failed(o, "Merge requires file-level merging");
1560 goto done;
1561 }
1562
1563 if (!o->skip_sparse_checkout) {
1564 int empty_worktree = 1;
1565
1566 /*
1567 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1568 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1569 * so apply_sparse_checkout() won't attempt to remove it from worktree
1570 */
1571 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1572
1573 ret = 0;
1574 for (i = 0; i < o->result.cache_nr; i++) {
1575 struct cache_entry *ce = o->result.cache[i];
1576
1577 /*
1578 * Entries marked with CE_ADDED in merged_entry() do not have
1579 * verify_absent() check (the check is effectively disabled
1580 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1581 *
1582 * Do the real check now because we have had
1583 * correct CE_NEW_SKIP_WORKTREE
1584 */
1585 if (ce->ce_flags & CE_ADDED &&
1586 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1587 if (!o->show_all_errors)
1588 goto return_failed;
1589 ret = -1;
1590 }
1591
1592 if (apply_sparse_checkout(&o->result, ce, o)) {
1593 if (!o->show_all_errors)
1594 goto return_failed;
1595 ret = -1;
1596 }
1597 if (!ce_skip_worktree(ce))
1598 empty_worktree = 0;
1599
1600 }
1601 if (ret < 0)
1602 goto return_failed;
1603 /*
1604 * Sparse checkout is meant to narrow down checkout area
1605 * but it does not make sense to narrow down to empty working
1606 * tree. This is usually a mistake in sparse checkout rules.
1607 * Do not allow users to do that.
1608 */
1609 if (o->result.cache_nr && empty_worktree) {
1610 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1611 goto done;
1612 }
1613 }
1614
1615 ret = check_updates(o) ? (-2) : 0;
1616 if (o->dst_index) {
1617 move_index_extensions(&o->result, o->src_index);
1618 if (!ret) {
1619 if (git_env_bool("GIT_TEST_CHECK_CACHE_TREE", 0))
1620 cache_tree_verify(the_repository, &o->result);
1621 if (!o->result.cache_tree)
1622 o->result.cache_tree = cache_tree();
1623 if (!cache_tree_fully_valid(o->result.cache_tree))
1624 cache_tree_update(&o->result,
1625 WRITE_TREE_SILENT |
1626 WRITE_TREE_REPAIR);
1627 }
1628
1629 o->result.updated_workdir = 1;
1630 discard_index(o->dst_index);
1631 *o->dst_index = o->result;
1632 } else {
1633 discard_index(&o->result);
1634 }
1635 o->src_index = NULL;
1636
1637 done:
1638 trace_performance_leave("unpack_trees");
1639 clear_exclude_list(&el);
1640 return ret;
1641
1642 return_failed:
1643 if (o->show_all_errors)
1644 display_error_msgs(o);
1645 mark_all_ce_unused(o->src_index);
1646 ret = unpack_failed(o, NULL);
1647 if (o->exiting_early)
1648 ret = 0;
1649 goto done;
1650 }
1651
1652 /* Here come the merge functions */
1653
1654 static int reject_merge(const struct cache_entry *ce,
1655 struct unpack_trees_options *o)
1656 {
1657 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1658 }
1659
1660 static int same(const struct cache_entry *a, const struct cache_entry *b)
1661 {
1662 if (!!a != !!b)
1663 return 0;
1664 if (!a && !b)
1665 return 1;
1666 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1667 return 0;
1668 return a->ce_mode == b->ce_mode &&
1669 oideq(&a->oid, &b->oid);
1670 }
1671
1672
1673 /*
1674 * When a CE gets turned into an unmerged entry, we
1675 * want it to be up-to-date
1676 */
1677 static int verify_uptodate_1(const struct cache_entry *ce,
1678 struct unpack_trees_options *o,
1679 enum unpack_trees_error_types error_type)
1680 {
1681 struct stat st;
1682
1683 if (o->index_only)
1684 return 0;
1685
1686 /*
1687 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1688 * if this entry is truly up-to-date because this file may be
1689 * overwritten.
1690 */
1691 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1692 ; /* keep checking */
1693 else if (o->reset || ce_uptodate(ce))
1694 return 0;
1695
1696 if (!lstat(ce->name, &st)) {
1697 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1698 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1699
1700 if (submodule_from_ce(ce)) {
1701 int r = check_submodule_move_head(ce,
1702 "HEAD", oid_to_hex(&ce->oid), o);
1703 if (r)
1704 return add_rejected_path(o, error_type, ce->name);
1705 return 0;
1706 }
1707
1708 if (!changed)
1709 return 0;
1710 /*
1711 * Historic default policy was to allow submodule to be out
1712 * of sync wrt the superproject index. If the submodule was
1713 * not considered interesting above, we don't care here.
1714 */
1715 if (S_ISGITLINK(ce->ce_mode))
1716 return 0;
1717
1718 errno = 0;
1719 }
1720 if (errno == ENOENT)
1721 return 0;
1722 return add_rejected_path(o, error_type, ce->name);
1723 }
1724
1725 int verify_uptodate(const struct cache_entry *ce,
1726 struct unpack_trees_options *o)
1727 {
1728 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1729 return 0;
1730 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1731 }
1732
1733 static int verify_uptodate_sparse(const struct cache_entry *ce,
1734 struct unpack_trees_options *o)
1735 {
1736 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1737 }
1738
1739 /*
1740 * TODO: We should actually invalidate o->result, not src_index [1].
1741 * But since cache tree and untracked cache both are not copied to
1742 * o->result until unpacking is complete, we invalidate them on
1743 * src_index instead with the assumption that they will be copied to
1744 * dst_index at the end.
1745 *
1746 * [1] src_index->cache_tree is also used in unpack_callback() so if
1747 * we invalidate o->result, we need to update it to use
1748 * o->result.cache_tree as well.
1749 */
1750 static void invalidate_ce_path(const struct cache_entry *ce,
1751 struct unpack_trees_options *o)
1752 {
1753 if (!ce)
1754 return;
1755 cache_tree_invalidate_path(o->src_index, ce->name);
1756 untracked_cache_invalidate_path(o->src_index, ce->name, 1);
1757 }
1758
1759 /*
1760 * Check that checking out ce->sha1 in subdir ce->name is not
1761 * going to overwrite any working files.
1762 *
1763 * Currently, git does not checkout subprojects during a superproject
1764 * checkout, so it is not going to overwrite anything.
1765 */
1766 static int verify_clean_submodule(const char *old_sha1,
1767 const struct cache_entry *ce,
1768 struct unpack_trees_options *o)
1769 {
1770 if (!submodule_from_ce(ce))
1771 return 0;
1772
1773 return check_submodule_move_head(ce, old_sha1,
1774 oid_to_hex(&ce->oid), o);
1775 }
1776
1777 static int verify_clean_subdirectory(const struct cache_entry *ce,
1778 struct unpack_trees_options *o)
1779 {
1780 /*
1781 * we are about to extract "ce->name"; we would not want to lose
1782 * anything in the existing directory there.
1783 */
1784 int namelen;
1785 int i;
1786 struct dir_struct d;
1787 char *pathbuf;
1788 int cnt = 0;
1789
1790 if (S_ISGITLINK(ce->ce_mode)) {
1791 struct object_id oid;
1792 int sub_head = resolve_gitlink_ref(ce->name, "HEAD", &oid);
1793 /*
1794 * If we are not going to update the submodule, then
1795 * we don't care.
1796 */
1797 if (!sub_head && oideq(&oid, &ce->oid))
1798 return 0;
1799 return verify_clean_submodule(sub_head ? NULL : oid_to_hex(&oid),
1800 ce, o);
1801 }
1802
1803 /*
1804 * First let's make sure we do not have a local modification
1805 * in that directory.
1806 */
1807 namelen = ce_namelen(ce);
1808 for (i = locate_in_src_index(ce, o);
1809 i < o->src_index->cache_nr;
1810 i++) {
1811 struct cache_entry *ce2 = o->src_index->cache[i];
1812 int len = ce_namelen(ce2);
1813 if (len < namelen ||
1814 strncmp(ce->name, ce2->name, namelen) ||
1815 ce2->name[namelen] != '/')
1816 break;
1817 /*
1818 * ce2->name is an entry in the subdirectory to be
1819 * removed.
1820 */
1821 if (!ce_stage(ce2)) {
1822 if (verify_uptodate(ce2, o))
1823 return -1;
1824 add_entry(o, ce2, CE_REMOVE, 0);
1825 invalidate_ce_path(ce, o);
1826 mark_ce_used(ce2, o);
1827 }
1828 cnt++;
1829 }
1830
1831 /*
1832 * Then we need to make sure that we do not lose a locally
1833 * present file that is not ignored.
1834 */
1835 pathbuf = xstrfmt("%.*s/", namelen, ce->name);
1836
1837 memset(&d, 0, sizeof(d));
1838 if (o->dir)
1839 d.exclude_per_dir = o->dir->exclude_per_dir;
1840 i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL);
1841 if (i)
1842 return add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1843 free(pathbuf);
1844 return cnt;
1845 }
1846
1847 /*
1848 * This gets called when there was no index entry for the tree entry 'dst',
1849 * but we found a file in the working tree that 'lstat()' said was fine,
1850 * and we're on a case-insensitive filesystem.
1851 *
1852 * See if we can find a case-insensitive match in the index that also
1853 * matches the stat information, and assume it's that other file!
1854 */
1855 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1856 {
1857 const struct cache_entry *src;
1858
1859 src = index_file_exists(o->src_index, name, len, 1);
1860 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1861 }
1862
1863 static int check_ok_to_remove(const char *name, int len, int dtype,
1864 const struct cache_entry *ce, struct stat *st,
1865 enum unpack_trees_error_types error_type,
1866 struct unpack_trees_options *o)
1867 {
1868 const struct cache_entry *result;
1869
1870 /*
1871 * It may be that the 'lstat()' succeeded even though
1872 * target 'ce' was absent, because there is an old
1873 * entry that is different only in case..
1874 *
1875 * Ignore that lstat() if it matches.
1876 */
1877 if (ignore_case && icase_exists(o, name, len, st))
1878 return 0;
1879
1880 if (o->dir &&
1881 is_excluded(o->dir, o->src_index, name, &dtype))
1882 /*
1883 * ce->name is explicitly excluded, so it is Ok to
1884 * overwrite it.
1885 */
1886 return 0;
1887 if (S_ISDIR(st->st_mode)) {
1888 /*
1889 * We are checking out path "foo" and
1890 * found "foo/." in the working tree.
1891 * This is tricky -- if we have modified
1892 * files that are in "foo/" we would lose
1893 * them.
1894 */
1895 if (verify_clean_subdirectory(ce, o) < 0)
1896 return -1;
1897 return 0;
1898 }
1899
1900 /*
1901 * The previous round may already have decided to
1902 * delete this path, which is in a subdirectory that
1903 * is being replaced with a blob.
1904 */
1905 result = index_file_exists(&o->result, name, len, 0);
1906 if (result) {
1907 if (result->ce_flags & CE_REMOVE)
1908 return 0;
1909 }
1910
1911 return add_rejected_path(o, error_type, name);
1912 }
1913
1914 /*
1915 * We do not want to remove or overwrite a working tree file that
1916 * is not tracked, unless it is ignored.
1917 */
1918 static int verify_absent_1(const struct cache_entry *ce,
1919 enum unpack_trees_error_types error_type,
1920 struct unpack_trees_options *o)
1921 {
1922 int len;
1923 struct stat st;
1924
1925 if (o->index_only || o->reset || !o->update)
1926 return 0;
1927
1928 len = check_leading_path(ce->name, ce_namelen(ce));
1929 if (!len)
1930 return 0;
1931 else if (len > 0) {
1932 char *path;
1933 int ret;
1934
1935 path = xmemdupz(ce->name, len);
1936 if (lstat(path, &st))
1937 ret = error_errno("cannot stat '%s'", path);
1938 else {
1939 if (submodule_from_ce(ce))
1940 ret = check_submodule_move_head(ce,
1941 oid_to_hex(&ce->oid),
1942 NULL, o);
1943 else
1944 ret = check_ok_to_remove(path, len, DT_UNKNOWN, NULL,
1945 &st, error_type, o);
1946 }
1947 free(path);
1948 return ret;
1949 } else if (lstat(ce->name, &st)) {
1950 if (errno != ENOENT)
1951 return error_errno("cannot stat '%s'", ce->name);
1952 return 0;
1953 } else {
1954 if (submodule_from_ce(ce))
1955 return check_submodule_move_head(ce, oid_to_hex(&ce->oid),
1956 NULL, o);
1957
1958 return check_ok_to_remove(ce->name, ce_namelen(ce),
1959 ce_to_dtype(ce), ce, &st,
1960 error_type, o);
1961 }
1962 }
1963
1964 static int verify_absent(const struct cache_entry *ce,
1965 enum unpack_trees_error_types error_type,
1966 struct unpack_trees_options *o)
1967 {
1968 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1969 return 0;
1970 return verify_absent_1(ce, error_type, o);
1971 }
1972
1973 static int verify_absent_sparse(const struct cache_entry *ce,
1974 enum unpack_trees_error_types error_type,
1975 struct unpack_trees_options *o)
1976 {
1977 enum unpack_trees_error_types orphaned_error = error_type;
1978 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1979 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1980
1981 return verify_absent_1(ce, orphaned_error, o);
1982 }
1983
1984 static int merged_entry(const struct cache_entry *ce,
1985 const struct cache_entry *old,
1986 struct unpack_trees_options *o)
1987 {
1988 int update = CE_UPDATE;
1989 struct cache_entry *merge = dup_cache_entry(ce, &o->result);
1990
1991 if (!old) {
1992 /*
1993 * New index entries. In sparse checkout, the following
1994 * verify_absent() will be delayed until after
1995 * traverse_trees() finishes in unpack_trees(), then:
1996 *
1997 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1998 * - verify_absent() be called again, this time with
1999 * correct CE_NEW_SKIP_WORKTREE
2000 *
2001 * verify_absent() call here does nothing in sparse
2002 * checkout (i.e. o->skip_sparse_checkout == 0)
2003 */
2004 update |= CE_ADDED;
2005 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
2006
2007 if (verify_absent(merge,
2008 ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
2009 discard_cache_entry(merge);
2010 return -1;
2011 }
2012 invalidate_ce_path(merge, o);
2013
2014 if (submodule_from_ce(ce)) {
2015 int ret = check_submodule_move_head(ce, NULL,
2016 oid_to_hex(&ce->oid),
2017 o);
2018 if (ret)
2019 return ret;
2020 }
2021
2022 } else if (!(old->ce_flags & CE_CONFLICTED)) {
2023 /*
2024 * See if we can re-use the old CE directly?
2025 * That way we get the uptodate stat info.
2026 *
2027 * This also removes the UPDATE flag on a match; otherwise
2028 * we will end up overwriting local changes in the work tree.
2029 */
2030 if (same(old, merge)) {
2031 copy_cache_entry(merge, old);
2032 update = 0;
2033 } else {
2034 if (verify_uptodate(old, o)) {
2035 discard_cache_entry(merge);
2036 return -1;
2037 }
2038 /* Migrate old flags over */
2039 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
2040 invalidate_ce_path(old, o);
2041 }
2042
2043 if (submodule_from_ce(ce)) {
2044 int ret = check_submodule_move_head(ce, oid_to_hex(&old->oid),
2045 oid_to_hex(&ce->oid),
2046 o);
2047 if (ret)
2048 return ret;
2049 }
2050 } else {
2051 /*
2052 * Previously unmerged entry left as an existence
2053 * marker by read_index_unmerged();
2054 */
2055 invalidate_ce_path(old, o);
2056 }
2057
2058 do_add_entry(o, merge, update, CE_STAGEMASK);
2059 return 1;
2060 }
2061
2062 static int deleted_entry(const struct cache_entry *ce,
2063 const struct cache_entry *old,
2064 struct unpack_trees_options *o)
2065 {
2066 /* Did it exist in the index? */
2067 if (!old) {
2068 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2069 return -1;
2070 return 0;
2071 }
2072 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
2073 return -1;
2074 add_entry(o, ce, CE_REMOVE, 0);
2075 invalidate_ce_path(ce, o);
2076 return 1;
2077 }
2078
2079 static int keep_entry(const struct cache_entry *ce,
2080 struct unpack_trees_options *o)
2081 {
2082 add_entry(o, ce, 0, 0);
2083 if (ce_stage(ce))
2084 invalidate_ce_path(ce, o);
2085 return 1;
2086 }
2087
2088 #if DBRT_DEBUG
2089 static void show_stage_entry(FILE *o,
2090 const char *label, const struct cache_entry *ce)
2091 {
2092 if (!ce)
2093 fprintf(o, "%s (missing)\n", label);
2094 else
2095 fprintf(o, "%s%06o %s %d\t%s\n",
2096 label,
2097 ce->ce_mode,
2098 oid_to_hex(&ce->oid),
2099 ce_stage(ce),
2100 ce->name);
2101 }
2102 #endif
2103
2104 int threeway_merge(const struct cache_entry * const *stages,
2105 struct unpack_trees_options *o)
2106 {
2107 const struct cache_entry *index;
2108 const struct cache_entry *head;
2109 const struct cache_entry *remote = stages[o->head_idx + 1];
2110 int count;
2111 int head_match = 0;
2112 int remote_match = 0;
2113
2114 int df_conflict_head = 0;
2115 int df_conflict_remote = 0;
2116
2117 int any_anc_missing = 0;
2118 int no_anc_exists = 1;
2119 int i;
2120
2121 for (i = 1; i < o->head_idx; i++) {
2122 if (!stages[i] || stages[i] == o->df_conflict_entry)
2123 any_anc_missing = 1;
2124 else
2125 no_anc_exists = 0;
2126 }
2127
2128 index = stages[0];
2129 head = stages[o->head_idx];
2130
2131 if (head == o->df_conflict_entry) {
2132 df_conflict_head = 1;
2133 head = NULL;
2134 }
2135
2136 if (remote == o->df_conflict_entry) {
2137 df_conflict_remote = 1;
2138 remote = NULL;
2139 }
2140
2141 /*
2142 * First, if there's a #16 situation, note that to prevent #13
2143 * and #14.
2144 */
2145 if (!same(remote, head)) {
2146 for (i = 1; i < o->head_idx; i++) {
2147 if (same(stages[i], head)) {
2148 head_match = i;
2149 }
2150 if (same(stages[i], remote)) {
2151 remote_match = i;
2152 }
2153 }
2154 }
2155
2156 /*
2157 * We start with cases where the index is allowed to match
2158 * something other than the head: #14(ALT) and #2ALT, where it
2159 * is permitted to match the result instead.
2160 */
2161 /* #14, #14ALT, #2ALT */
2162 if (remote && !df_conflict_head && head_match && !remote_match) {
2163 if (index && !same(index, remote) && !same(index, head))
2164 return reject_merge(index, o);
2165 return merged_entry(remote, index, o);
2166 }
2167 /*
2168 * If we have an entry in the index cache, then we want to
2169 * make sure that it matches head.
2170 */
2171 if (index && !same(index, head))
2172 return reject_merge(index, o);
2173
2174 if (head) {
2175 /* #5ALT, #15 */
2176 if (same(head, remote))
2177 return merged_entry(head, index, o);
2178 /* #13, #3ALT */
2179 if (!df_conflict_remote && remote_match && !head_match)
2180 return merged_entry(head, index, o);
2181 }
2182
2183 /* #1 */
2184 if (!head && !remote && any_anc_missing)
2185 return 0;
2186
2187 /*
2188 * Under the "aggressive" rule, we resolve mostly trivial
2189 * cases that we historically had git-merge-one-file resolve.
2190 */
2191 if (o->aggressive) {
2192 int head_deleted = !head;
2193 int remote_deleted = !remote;
2194 const struct cache_entry *ce = NULL;
2195
2196 if (index)
2197 ce = index;
2198 else if (head)
2199 ce = head;
2200 else if (remote)
2201 ce = remote;
2202 else {
2203 for (i = 1; i < o->head_idx; i++) {
2204 if (stages[i] && stages[i] != o->df_conflict_entry) {
2205 ce = stages[i];
2206 break;
2207 }
2208 }
2209 }
2210
2211 /*
2212 * Deleted in both.
2213 * Deleted in one and unchanged in the other.
2214 */
2215 if ((head_deleted && remote_deleted) ||
2216 (head_deleted && remote && remote_match) ||
2217 (remote_deleted && head && head_match)) {
2218 if (index)
2219 return deleted_entry(index, index, o);
2220 if (ce && !head_deleted) {
2221 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2222 return -1;
2223 }
2224 return 0;
2225 }
2226 /*
2227 * Added in both, identically.
2228 */
2229 if (no_anc_exists && head && remote && same(head, remote))
2230 return merged_entry(head, index, o);
2231
2232 }
2233
2234 /* Below are "no merge" cases, which require that the index be
2235 * up-to-date to avoid the files getting overwritten with
2236 * conflict resolution files.
2237 */
2238 if (index) {
2239 if (verify_uptodate(index, o))
2240 return -1;
2241 }
2242
2243 o->nontrivial_merge = 1;
2244
2245 /* #2, #3, #4, #6, #7, #9, #10, #11. */
2246 count = 0;
2247 if (!head_match || !remote_match) {
2248 for (i = 1; i < o->head_idx; i++) {
2249 if (stages[i] && stages[i] != o->df_conflict_entry) {
2250 keep_entry(stages[i], o);
2251 count++;
2252 break;
2253 }
2254 }
2255 }
2256 #if DBRT_DEBUG
2257 else {
2258 fprintf(stderr, "read-tree: warning #16 detected\n");
2259 show_stage_entry(stderr, "head ", stages[head_match]);
2260 show_stage_entry(stderr, "remote ", stages[remote_match]);
2261 }
2262 #endif
2263 if (head) { count += keep_entry(head, o); }
2264 if (remote) { count += keep_entry(remote, o); }
2265 return count;
2266 }
2267
2268 /*
2269 * Two-way merge.
2270 *
2271 * The rule is to "carry forward" what is in the index without losing
2272 * information across a "fast-forward", favoring a successful merge
2273 * over a merge failure when it makes sense. For details of the
2274 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
2275 *
2276 */
2277 int twoway_merge(const struct cache_entry * const *src,
2278 struct unpack_trees_options *o)
2279 {
2280 const struct cache_entry *current = src[0];
2281 const struct cache_entry *oldtree = src[1];
2282 const struct cache_entry *newtree = src[2];
2283
2284 if (o->merge_size != 2)
2285 return error("Cannot do a twoway merge of %d trees",
2286 o->merge_size);
2287
2288 if (oldtree == o->df_conflict_entry)
2289 oldtree = NULL;
2290 if (newtree == o->df_conflict_entry)
2291 newtree = NULL;
2292
2293 if (current) {
2294 if (current->ce_flags & CE_CONFLICTED) {
2295 if (same(oldtree, newtree) || o->reset) {
2296 if (!newtree)
2297 return deleted_entry(current, current, o);
2298 else
2299 return merged_entry(newtree, current, o);
2300 }
2301 return reject_merge(current, o);
2302 } else if ((!oldtree && !newtree) || /* 4 and 5 */
2303 (!oldtree && newtree &&
2304 same(current, newtree)) || /* 6 and 7 */
2305 (oldtree && newtree &&
2306 same(oldtree, newtree)) || /* 14 and 15 */
2307 (oldtree && newtree &&
2308 !same(oldtree, newtree) && /* 18 and 19 */
2309 same(current, newtree))) {
2310 return keep_entry(current, o);
2311 } else if (oldtree && !newtree && same(current, oldtree)) {
2312 /* 10 or 11 */
2313 return deleted_entry(oldtree, current, o);
2314 } else if (oldtree && newtree &&
2315 same(current, oldtree) && !same(current, newtree)) {
2316 /* 20 or 21 */
2317 return merged_entry(newtree, current, o);
2318 } else
2319 return reject_merge(current, o);
2320 }
2321 else if (newtree) {
2322 if (oldtree && !o->initial_checkout) {
2323 /*
2324 * deletion of the path was staged;
2325 */
2326 if (same(oldtree, newtree))
2327 return 1;
2328 return reject_merge(oldtree, o);
2329 }
2330 return merged_entry(newtree, current, o);
2331 }
2332 return deleted_entry(oldtree, current, o);
2333 }
2334
2335 /*
2336 * Bind merge.
2337 *
2338 * Keep the index entries at stage0, collapse stage1 but make sure
2339 * stage0 does not have anything there.
2340 */
2341 int bind_merge(const struct cache_entry * const *src,
2342 struct unpack_trees_options *o)
2343 {
2344 const struct cache_entry *old = src[0];
2345 const struct cache_entry *a = src[1];
2346
2347 if (o->merge_size != 1)
2348 return error("Cannot do a bind merge of %d trees",
2349 o->merge_size);
2350 if (a && old)
2351 return o->quiet ? -1 :
2352 error(ERRORMSG(o, ERROR_BIND_OVERLAP),
2353 super_prefixed(a->name),
2354 super_prefixed(old->name));
2355 if (!a)
2356 return keep_entry(old, o);
2357 else
2358 return merged_entry(a, NULL, o);
2359 }
2360
2361 /*
2362 * One-way merge.
2363 *
2364 * The rule is:
2365 * - take the stat information from stage0, take the data from stage1
2366 */
2367 int oneway_merge(const struct cache_entry * const *src,
2368 struct unpack_trees_options *o)
2369 {
2370 const struct cache_entry *old = src[0];
2371 const struct cache_entry *a = src[1];
2372
2373 if (o->merge_size != 1)
2374 return error("Cannot do a oneway merge of %d trees",
2375 o->merge_size);
2376
2377 if (!a || a == o->df_conflict_entry)
2378 return deleted_entry(old, old, o);
2379
2380 if (old && same(old, a)) {
2381 int update = 0;
2382 if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
2383 struct stat st;
2384 if (lstat(old->name, &st) ||
2385 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
2386 update |= CE_UPDATE;
2387 }
2388 if (o->update && S_ISGITLINK(old->ce_mode) &&
2389 should_update_submodules() && !verify_uptodate(old, o))
2390 update |= CE_UPDATE;
2391 add_entry(o, old, update, CE_STAGEMASK);
2392 return 0;
2393 }
2394 return merged_entry(a, old, o);
2395 }