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