22c41a3ba80971e5edc6bbf02eb6ea59d3c41277
[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->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 name_entry *names,
711 struct traverse_info *info)
712 {
713 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
714 struct unpack_trees_options *o = info->data;
715 struct cache_entry *tree_ce = NULL;
716 int ce_len = 0;
717 int i, d;
718
719 if (!o->merge)
720 BUG("We need cache-tree to do this optimization");
721
722 /*
723 * Do what unpack_callback() and unpack_nondirectories() normally
724 * do. But we walk all paths in an iterative loop instead.
725 *
726 * D/F conflicts and higher stage entries are not a concern
727 * because cache-tree would be invalidated and we would never
728 * get here in the first place.
729 */
730 for (i = 0; i < nr_entries; i++) {
731 int new_ce_len, len, rc;
732
733 src[0] = o->src_index->cache[pos + i];
734
735 len = ce_namelen(src[0]);
736 new_ce_len = cache_entry_size(len);
737
738 if (new_ce_len > ce_len) {
739 new_ce_len <<= 1;
740 tree_ce = xrealloc(tree_ce, new_ce_len);
741 memset(tree_ce, 0, new_ce_len);
742 ce_len = new_ce_len;
743
744 tree_ce->ce_flags = create_ce_flags(0);
745
746 for (d = 1; d <= nr_names; d++)
747 src[d] = tree_ce;
748 }
749
750 tree_ce->ce_mode = src[0]->ce_mode;
751 tree_ce->ce_namelen = len;
752 oidcpy(&tree_ce->oid, &src[0]->oid);
753 memcpy(tree_ce->name, src[0]->name, len + 1);
754
755 rc = call_unpack_fn((const struct cache_entry * const *)src, o);
756 if (rc < 0) {
757 free(tree_ce);
758 return rc;
759 }
760
761 mark_ce_used(src[0], o);
762 }
763 free(tree_ce);
764 if (o->debug_unpack)
765 printf("Unpacked %d entries from %s to %s using cache-tree\n",
766 nr_entries,
767 o->src_index->cache[pos]->name,
768 o->src_index->cache[pos + nr_entries - 1]->name);
769 return 0;
770 }
771
772 static int traverse_trees_recursive(int n, unsigned long dirmask,
773 unsigned long df_conflicts,
774 struct name_entry *names,
775 struct traverse_info *info)
776 {
777 struct unpack_trees_options *o = info->data;
778 int i, ret, bottom;
779 int nr_buf = 0;
780 struct tree_desc t[MAX_UNPACK_TREES];
781 void *buf[MAX_UNPACK_TREES];
782 struct traverse_info newinfo;
783 struct name_entry *p;
784 int nr_entries;
785
786 nr_entries = all_trees_same_as_cache_tree(n, dirmask, names, info);
787 if (nr_entries > 0) {
788 int pos = index_pos_by_traverse_info(names, info);
789
790 if (!o->merge || df_conflicts)
791 BUG("Wrong condition to get here buddy");
792
793 /*
794 * All entries up to 'pos' must have been processed
795 * (i.e. marked CE_UNPACKED) at this point. But to be safe,
796 * save and restore cache_bottom anyway to not miss
797 * unprocessed entries before 'pos'.
798 */
799 bottom = o->cache_bottom;
800 ret = traverse_by_cache_tree(pos, nr_entries, n, names, info);
801 o->cache_bottom = bottom;
802 return ret;
803 }
804
805 p = names;
806 while (!p->mode)
807 p++;
808
809 newinfo = *info;
810 newinfo.prev = info;
811 newinfo.pathspec = info->pathspec;
812 newinfo.name = *p;
813 newinfo.pathlen += tree_entry_len(p) + 1;
814 newinfo.df_conflicts |= df_conflicts;
815
816 /*
817 * Fetch the tree from the ODB for each peer directory in the
818 * n commits.
819 *
820 * For 2- and 3-way traversals, we try to avoid hitting the
821 * ODB twice for the same OID. This should yield a nice speed
822 * up in checkouts and merges when the commits are similar.
823 *
824 * We don't bother doing the full O(n^2) search for larger n,
825 * because wider traversals don't happen that often and we
826 * avoid the search setup.
827 *
828 * When 2 peer OIDs are the same, we just copy the tree
829 * descriptor data. This implicitly borrows the buffer
830 * data from the earlier cell.
831 */
832 for (i = 0; i < n; i++, dirmask >>= 1) {
833 if (i > 0 && are_same_oid(&names[i], &names[i - 1]))
834 t[i] = t[i - 1];
835 else if (i > 1 && are_same_oid(&names[i], &names[i - 2]))
836 t[i] = t[i - 2];
837 else {
838 const struct object_id *oid = NULL;
839 if (dirmask & 1)
840 oid = &names[i].oid;
841 buf[nr_buf++] = fill_tree_descriptor(t + i, oid);
842 }
843 }
844
845 bottom = switch_cache_bottom(&newinfo);
846 ret = traverse_trees(o->src_index, n, t, &newinfo);
847 restore_cache_bottom(&newinfo, bottom);
848
849 for (i = 0; i < nr_buf; i++)
850 free(buf[i]);
851
852 return ret;
853 }
854
855 /*
856 * Compare the traverse-path to the cache entry without actually
857 * having to generate the textual representation of the traverse
858 * path.
859 *
860 * NOTE! This *only* compares up to the size of the traverse path
861 * itself - the caller needs to do the final check for the cache
862 * entry having more data at the end!
863 */
864 static int do_compare_entry_piecewise(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
865 {
866 int len, pathlen, ce_len;
867 const char *ce_name;
868
869 if (info->prev) {
870 int cmp = do_compare_entry_piecewise(ce, info->prev,
871 &info->name);
872 if (cmp)
873 return cmp;
874 }
875 pathlen = info->pathlen;
876 ce_len = ce_namelen(ce);
877
878 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
879 if (ce_len < pathlen)
880 return -1;
881
882 ce_len -= pathlen;
883 ce_name = ce->name + pathlen;
884
885 len = tree_entry_len(n);
886 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
887 }
888
889 static int do_compare_entry(const struct cache_entry *ce,
890 const struct traverse_info *info,
891 const struct name_entry *n)
892 {
893 int len, pathlen, ce_len;
894 const char *ce_name;
895 int cmp;
896
897 /*
898 * If we have not precomputed the traverse path, it is quicker
899 * to avoid doing so. But if we have precomputed it,
900 * it is quicker to use the precomputed version.
901 */
902 if (!info->traverse_path)
903 return do_compare_entry_piecewise(ce, info, n);
904
905 cmp = strncmp(ce->name, info->traverse_path, info->pathlen);
906 if (cmp)
907 return cmp;
908
909 pathlen = info->pathlen;
910 ce_len = ce_namelen(ce);
911
912 if (ce_len < pathlen)
913 return -1;
914
915 ce_len -= pathlen;
916 ce_name = ce->name + pathlen;
917
918 len = tree_entry_len(n);
919 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
920 }
921
922 static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
923 {
924 int cmp = do_compare_entry(ce, info, n);
925 if (cmp)
926 return cmp;
927
928 /*
929 * Even if the beginning compared identically, the ce should
930 * compare as bigger than a directory leading up to it!
931 */
932 return ce_namelen(ce) > traverse_path_len(info, n);
933 }
934
935 static int ce_in_traverse_path(const struct cache_entry *ce,
936 const struct traverse_info *info)
937 {
938 if (!info->prev)
939 return 1;
940 if (do_compare_entry(ce, info->prev, &info->name))
941 return 0;
942 /*
943 * If ce (blob) is the same name as the path (which is a tree
944 * we will be descending into), it won't be inside it.
945 */
946 return (info->pathlen < ce_namelen(ce));
947 }
948
949 static struct cache_entry *create_ce_entry(const struct traverse_info *info,
950 const struct name_entry *n,
951 int stage,
952 struct index_state *istate,
953 int is_transient)
954 {
955 int len = traverse_path_len(info, n);
956 struct cache_entry *ce =
957 is_transient ?
958 make_empty_transient_cache_entry(len) :
959 make_empty_cache_entry(istate, len);
960
961 ce->ce_mode = create_ce_mode(n->mode);
962 ce->ce_flags = create_ce_flags(stage);
963 ce->ce_namelen = len;
964 oidcpy(&ce->oid, &n->oid);
965 make_traverse_path(ce->name, info, n);
966
967 return ce;
968 }
969
970 /*
971 * Note that traverse_by_cache_tree() duplicates some logic in this function
972 * without actually calling it. If you change the logic here you may need to
973 * check and change there as well.
974 */
975 static int unpack_nondirectories(int n, unsigned long mask,
976 unsigned long dirmask,
977 struct cache_entry **src,
978 const struct name_entry *names,
979 const struct traverse_info *info)
980 {
981 int i;
982 struct unpack_trees_options *o = info->data;
983 unsigned long conflicts = info->df_conflicts | dirmask;
984
985 /* Do we have *only* directories? Nothing to do */
986 if (mask == dirmask && !src[0])
987 return 0;
988
989 /*
990 * Ok, we've filled in up to any potential index entry in src[0],
991 * now do the rest.
992 */
993 for (i = 0; i < n; i++) {
994 int stage;
995 unsigned int bit = 1ul << i;
996 if (conflicts & bit) {
997 src[i + o->merge] = o->df_conflict_entry;
998 continue;
999 }
1000 if (!(mask & bit))
1001 continue;
1002 if (!o->merge)
1003 stage = 0;
1004 else if (i + 1 < o->head_idx)
1005 stage = 1;
1006 else if (i + 1 > o->head_idx)
1007 stage = 3;
1008 else
1009 stage = 2;
1010
1011 /*
1012 * If the merge bit is set, then the cache entries are
1013 * discarded in the following block. In this case,
1014 * construct "transient" cache_entries, as they are
1015 * not stored in the index. otherwise construct the
1016 * cache entry from the index aware logic.
1017 */
1018 src[i + o->merge] = create_ce_entry(info, names + i, stage, &o->result, o->merge);
1019 }
1020
1021 if (o->merge) {
1022 int rc = call_unpack_fn((const struct cache_entry * const *)src,
1023 o);
1024 for (i = 0; i < n; i++) {
1025 struct cache_entry *ce = src[i + o->merge];
1026 if (ce != o->df_conflict_entry)
1027 discard_cache_entry(ce);
1028 }
1029 return rc;
1030 }
1031
1032 for (i = 0; i < n; i++)
1033 if (src[i] && src[i] != o->df_conflict_entry)
1034 if (do_add_entry(o, src[i], 0, 0))
1035 return -1;
1036
1037 return 0;
1038 }
1039
1040 static int unpack_failed(struct unpack_trees_options *o, const char *message)
1041 {
1042 discard_index(&o->result);
1043 if (!o->gently && !o->exiting_early) {
1044 if (message)
1045 return error("%s", message);
1046 return -1;
1047 }
1048 return -1;
1049 }
1050
1051 /*
1052 * The tree traversal is looking at name p. If we have a matching entry,
1053 * return it. If name p is a directory in the index, do not return
1054 * anything, as we will want to match it when the traversal descends into
1055 * the directory.
1056 */
1057 static int find_cache_pos(struct traverse_info *info,
1058 const struct name_entry *p)
1059 {
1060 int pos;
1061 struct unpack_trees_options *o = info->data;
1062 struct index_state *index = o->src_index;
1063 int pfxlen = info->pathlen;
1064 int p_len = tree_entry_len(p);
1065
1066 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
1067 const struct cache_entry *ce = index->cache[pos];
1068 const char *ce_name, *ce_slash;
1069 int cmp, ce_len;
1070
1071 if (ce->ce_flags & CE_UNPACKED) {
1072 /*
1073 * cache_bottom entry is already unpacked, so
1074 * we can never match it; don't check it
1075 * again.
1076 */
1077 if (pos == o->cache_bottom)
1078 ++o->cache_bottom;
1079 continue;
1080 }
1081 if (!ce_in_traverse_path(ce, info)) {
1082 /*
1083 * Check if we can skip future cache checks
1084 * (because we're already past all possible
1085 * entries in the traverse path).
1086 */
1087 if (info->traverse_path) {
1088 if (strncmp(ce->name, info->traverse_path,
1089 info->pathlen) > 0)
1090 break;
1091 }
1092 continue;
1093 }
1094 ce_name = ce->name + pfxlen;
1095 ce_slash = strchr(ce_name, '/');
1096 if (ce_slash)
1097 ce_len = ce_slash - ce_name;
1098 else
1099 ce_len = ce_namelen(ce) - pfxlen;
1100 cmp = name_compare(p->path, p_len, ce_name, ce_len);
1101 /*
1102 * Exact match; if we have a directory we need to
1103 * delay returning it.
1104 */
1105 if (!cmp)
1106 return ce_slash ? -2 - pos : pos;
1107 if (0 < cmp)
1108 continue; /* keep looking */
1109 /*
1110 * ce_name sorts after p->path; could it be that we
1111 * have files under p->path directory in the index?
1112 * E.g. ce_name == "t-i", and p->path == "t"; we may
1113 * have "t/a" in the index.
1114 */
1115 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
1116 ce_name[p_len] < '/')
1117 continue; /* keep looking */
1118 break;
1119 }
1120 return -1;
1121 }
1122
1123 static struct cache_entry *find_cache_entry(struct traverse_info *info,
1124 const struct name_entry *p)
1125 {
1126 int pos = find_cache_pos(info, p);
1127 struct unpack_trees_options *o = info->data;
1128
1129 if (0 <= pos)
1130 return o->src_index->cache[pos];
1131 else
1132 return NULL;
1133 }
1134
1135 static void debug_path(struct traverse_info *info)
1136 {
1137 if (info->prev) {
1138 debug_path(info->prev);
1139 if (*info->prev->name.path)
1140 putchar('/');
1141 }
1142 printf("%s", info->name.path);
1143 }
1144
1145 static void debug_name_entry(int i, struct name_entry *n)
1146 {
1147 printf("ent#%d %06o %s\n", i,
1148 n->path ? n->mode : 0,
1149 n->path ? n->path : "(missing)");
1150 }
1151
1152 static void debug_unpack_callback(int n,
1153 unsigned long mask,
1154 unsigned long dirmask,
1155 struct name_entry *names,
1156 struct traverse_info *info)
1157 {
1158 int i;
1159 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
1160 mask, dirmask, n);
1161 debug_path(info);
1162 putchar('\n');
1163 for (i = 0; i < n; i++)
1164 debug_name_entry(i, names + i);
1165 }
1166
1167 /*
1168 * Note that traverse_by_cache_tree() duplicates some logic in this function
1169 * without actually calling it. If you change the logic here you may need to
1170 * check and change there as well.
1171 */
1172 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
1173 {
1174 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
1175 struct unpack_trees_options *o = info->data;
1176 const struct name_entry *p = names;
1177
1178 /* Find first entry with a real name (we could use "mask" too) */
1179 while (!p->mode)
1180 p++;
1181
1182 if (o->debug_unpack)
1183 debug_unpack_callback(n, mask, dirmask, names, info);
1184
1185 /* Are we supposed to look at the index too? */
1186 if (o->merge) {
1187 while (1) {
1188 int cmp;
1189 struct cache_entry *ce;
1190
1191 if (o->diff_index_cached)
1192 ce = next_cache_entry(o);
1193 else
1194 ce = find_cache_entry(info, p);
1195
1196 if (!ce)
1197 break;
1198 cmp = compare_entry(ce, info, p);
1199 if (cmp < 0) {
1200 if (unpack_index_entry(ce, o) < 0)
1201 return unpack_failed(o, NULL);
1202 continue;
1203 }
1204 if (!cmp) {
1205 if (ce_stage(ce)) {
1206 /*
1207 * If we skip unmerged index
1208 * entries, we'll skip this
1209 * entry *and* the tree
1210 * entries associated with it!
1211 */
1212 if (o->skip_unmerged) {
1213 add_same_unmerged(ce, o);
1214 return mask;
1215 }
1216 }
1217 src[0] = ce;
1218 }
1219 break;
1220 }
1221 }
1222
1223 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
1224 return -1;
1225
1226 if (o->merge && src[0]) {
1227 if (ce_stage(src[0]))
1228 mark_ce_used_same_name(src[0], o);
1229 else
1230 mark_ce_used(src[0], o);
1231 }
1232
1233 /* Now handle any directories.. */
1234 if (dirmask) {
1235 /* special case: "diff-index --cached" looking at a tree */
1236 if (o->diff_index_cached &&
1237 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
1238 int matches;
1239 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
1240 names, info);
1241 /*
1242 * Everything under the name matches; skip the
1243 * entire hierarchy. diff_index_cached codepath
1244 * special cases D/F conflicts in such a way that
1245 * it does not do any look-ahead, so this is safe.
1246 */
1247 if (matches) {
1248 o->cache_bottom += matches;
1249 return mask;
1250 }
1251 }
1252
1253 if (traverse_trees_recursive(n, dirmask, mask & ~dirmask,
1254 names, info) < 0)
1255 return -1;
1256 return mask;
1257 }
1258
1259 return mask;
1260 }
1261
1262 static int clear_ce_flags_1(struct index_state *istate,
1263 struct cache_entry **cache, int nr,
1264 struct strbuf *prefix,
1265 int select_mask, int clear_mask,
1266 struct exclude_list *el, int defval);
1267
1268 /* Whole directory matching */
1269 static int clear_ce_flags_dir(struct index_state *istate,
1270 struct cache_entry **cache, int nr,
1271 struct strbuf *prefix,
1272 char *basename,
1273 int select_mask, int clear_mask,
1274 struct exclude_list *el, int defval)
1275 {
1276 struct cache_entry **cache_end;
1277 int dtype = DT_DIR;
1278 int ret = is_excluded_from_list(prefix->buf, prefix->len,
1279 basename, &dtype, el, istate);
1280 int rc;
1281
1282 strbuf_addch(prefix, '/');
1283
1284 /* If undecided, use matching result of parent dir in defval */
1285 if (ret < 0)
1286 ret = defval;
1287
1288 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
1289 struct cache_entry *ce = *cache_end;
1290 if (strncmp(ce->name, prefix->buf, prefix->len))
1291 break;
1292 }
1293
1294 /*
1295 * TODO: check el, if there are no patterns that may conflict
1296 * with ret (iow, we know in advance the incl/excl
1297 * decision for the entire directory), clear flag here without
1298 * calling clear_ce_flags_1(). That function will call
1299 * the expensive is_excluded_from_list() on every entry.
1300 */
1301 rc = clear_ce_flags_1(istate, cache, cache_end - cache,
1302 prefix,
1303 select_mask, clear_mask,
1304 el, ret);
1305 strbuf_setlen(prefix, prefix->len - 1);
1306 return rc;
1307 }
1308
1309 /*
1310 * Traverse the index, find every entry that matches according to
1311 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
1312 * number of traversed entries.
1313 *
1314 * If select_mask is non-zero, only entries whose ce_flags has on of
1315 * those bits enabled are traversed.
1316 *
1317 * cache : pointer to an index entry
1318 * prefix_len : an offset to its path
1319 *
1320 * The current path ("prefix") including the trailing '/' is
1321 * cache[0]->name[0..(prefix_len-1)]
1322 * Top level path has prefix_len zero.
1323 */
1324 static int clear_ce_flags_1(struct index_state *istate,
1325 struct cache_entry **cache, int nr,
1326 struct strbuf *prefix,
1327 int select_mask, int clear_mask,
1328 struct exclude_list *el, int defval)
1329 {
1330 struct cache_entry **cache_end = cache + nr;
1331
1332 /*
1333 * Process all entries that have the given prefix and meet
1334 * select_mask condition
1335 */
1336 while(cache != cache_end) {
1337 struct cache_entry *ce = *cache;
1338 const char *name, *slash;
1339 int len, dtype, ret;
1340
1341 if (select_mask && !(ce->ce_flags & select_mask)) {
1342 cache++;
1343 continue;
1344 }
1345
1346 if (prefix->len && strncmp(ce->name, prefix->buf, prefix->len))
1347 break;
1348
1349 name = ce->name + prefix->len;
1350 slash = strchr(name, '/');
1351
1352 /* If it's a directory, try whole directory match first */
1353 if (slash) {
1354 int processed;
1355
1356 len = slash - name;
1357 strbuf_add(prefix, name, len);
1358
1359 processed = clear_ce_flags_dir(istate, cache, cache_end - cache,
1360 prefix,
1361 prefix->buf + prefix->len - len,
1362 select_mask, clear_mask,
1363 el, defval);
1364
1365 /* clear_c_f_dir eats a whole dir already? */
1366 if (processed) {
1367 cache += processed;
1368 strbuf_setlen(prefix, prefix->len - len);
1369 continue;
1370 }
1371
1372 strbuf_addch(prefix, '/');
1373 cache += clear_ce_flags_1(istate, cache, cache_end - cache,
1374 prefix,
1375 select_mask, clear_mask, el, defval);
1376 strbuf_setlen(prefix, prefix->len - len - 1);
1377 continue;
1378 }
1379
1380 /* Non-directory */
1381 dtype = ce_to_dtype(ce);
1382 ret = is_excluded_from_list(ce->name, ce_namelen(ce),
1383 name, &dtype, el, istate);
1384 if (ret < 0)
1385 ret = defval;
1386 if (ret > 0)
1387 ce->ce_flags &= ~clear_mask;
1388 cache++;
1389 }
1390 return nr - (cache_end - cache);
1391 }
1392
1393 static int clear_ce_flags(struct index_state *istate,
1394 int select_mask, int clear_mask,
1395 struct exclude_list *el)
1396 {
1397 static struct strbuf prefix = STRBUF_INIT;
1398
1399 strbuf_reset(&prefix);
1400
1401 return clear_ce_flags_1(istate,
1402 istate->cache,
1403 istate->cache_nr,
1404 &prefix,
1405 select_mask, clear_mask,
1406 el, 0);
1407 }
1408
1409 /*
1410 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
1411 */
1412 static void mark_new_skip_worktree(struct exclude_list *el,
1413 struct index_state *istate,
1414 int select_flag, int skip_wt_flag)
1415 {
1416 int i;
1417
1418 /*
1419 * 1. Pretend the narrowest worktree: only unmerged entries
1420 * are checked out
1421 */
1422 for (i = 0; i < istate->cache_nr; i++) {
1423 struct cache_entry *ce = istate->cache[i];
1424
1425 if (select_flag && !(ce->ce_flags & select_flag))
1426 continue;
1427
1428 if (!ce_stage(ce) && !(ce->ce_flags & CE_CONFLICTED))
1429 ce->ce_flags |= skip_wt_flag;
1430 else
1431 ce->ce_flags &= ~skip_wt_flag;
1432 }
1433
1434 /*
1435 * 2. Widen worktree according to sparse-checkout file.
1436 * Matched entries will have skip_wt_flag cleared (i.e. "in")
1437 */
1438 clear_ce_flags(istate, select_flag, skip_wt_flag, el);
1439 }
1440
1441 static int verify_absent(const struct cache_entry *,
1442 enum unpack_trees_error_types,
1443 struct unpack_trees_options *);
1444 /*
1445 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
1446 * resulting index, -2 on failure to reflect the changes to the work tree.
1447 *
1448 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
1449 */
1450 int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
1451 {
1452 int i, ret;
1453 static struct cache_entry *dfc;
1454 struct exclude_list el;
1455
1456 if (len > MAX_UNPACK_TREES)
1457 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1458
1459 trace_performance_enter();
1460 memset(&el, 0, sizeof(el));
1461 if (!core_apply_sparse_checkout || !o->update)
1462 o->skip_sparse_checkout = 1;
1463 if (!o->skip_sparse_checkout) {
1464 char *sparse = git_pathdup("info/sparse-checkout");
1465 if (add_excludes_from_file_to_list(sparse, "", 0, &el, NULL) < 0)
1466 o->skip_sparse_checkout = 1;
1467 else
1468 o->el = &el;
1469 free(sparse);
1470 }
1471
1472 memset(&o->result, 0, sizeof(o->result));
1473 o->result.initialized = 1;
1474 o->result.timestamp.sec = o->src_index->timestamp.sec;
1475 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1476 o->result.version = o->src_index->version;
1477 if (!o->src_index->split_index) {
1478 o->result.split_index = NULL;
1479 } else if (o->src_index == o->dst_index) {
1480 /*
1481 * o->dst_index (and thus o->src_index) will be discarded
1482 * and overwritten with o->result at the end of this function,
1483 * so just use src_index's split_index to avoid having to
1484 * create a new one.
1485 */
1486 o->result.split_index = o->src_index->split_index;
1487 o->result.split_index->refcount++;
1488 } else {
1489 o->result.split_index = init_split_index(&o->result);
1490 }
1491 oidcpy(&o->result.oid, &o->src_index->oid);
1492 o->merge_size = len;
1493 mark_all_ce_unused(o->src_index);
1494
1495 /*
1496 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1497 */
1498 if (!o->skip_sparse_checkout)
1499 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1500
1501 if (!dfc)
1502 dfc = xcalloc(1, cache_entry_size(0));
1503 o->df_conflict_entry = dfc;
1504
1505 if (len) {
1506 const char *prefix = o->prefix ? o->prefix : "";
1507 struct traverse_info info;
1508
1509 setup_traverse_info(&info, prefix);
1510 info.fn = unpack_callback;
1511 info.data = o;
1512 info.show_all_errors = o->show_all_errors;
1513 info.pathspec = o->pathspec;
1514
1515 if (o->prefix) {
1516 /*
1517 * Unpack existing index entries that sort before the
1518 * prefix the tree is spliced into. Note that o->merge
1519 * is always true in this case.
1520 */
1521 while (1) {
1522 struct cache_entry *ce = next_cache_entry(o);
1523 if (!ce)
1524 break;
1525 if (ce_in_traverse_path(ce, &info))
1526 break;
1527 if (unpack_index_entry(ce, o) < 0)
1528 goto return_failed;
1529 }
1530 }
1531
1532 trace_performance_enter();
1533 ret = traverse_trees(o->src_index, len, t, &info);
1534 trace_performance_leave("traverse_trees");
1535 if (ret < 0)
1536 goto return_failed;
1537 }
1538
1539 /* Any left-over entries in the index? */
1540 if (o->merge) {
1541 while (1) {
1542 struct cache_entry *ce = next_cache_entry(o);
1543 if (!ce)
1544 break;
1545 if (unpack_index_entry(ce, o) < 0)
1546 goto return_failed;
1547 }
1548 }
1549 mark_all_ce_unused(o->src_index);
1550
1551 if (o->trivial_merges_only && o->nontrivial_merge) {
1552 ret = unpack_failed(o, "Merge requires file-level merging");
1553 goto done;
1554 }
1555
1556 if (!o->skip_sparse_checkout) {
1557 int empty_worktree = 1;
1558
1559 /*
1560 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1561 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1562 * so apply_sparse_checkout() won't attempt to remove it from worktree
1563 */
1564 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1565
1566 ret = 0;
1567 for (i = 0; i < o->result.cache_nr; i++) {
1568 struct cache_entry *ce = o->result.cache[i];
1569
1570 /*
1571 * Entries marked with CE_ADDED in merged_entry() do not have
1572 * verify_absent() check (the check is effectively disabled
1573 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1574 *
1575 * Do the real check now because we have had
1576 * correct CE_NEW_SKIP_WORKTREE
1577 */
1578 if (ce->ce_flags & CE_ADDED &&
1579 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1580 if (!o->show_all_errors)
1581 goto return_failed;
1582 ret = -1;
1583 }
1584
1585 if (apply_sparse_checkout(&o->result, ce, o)) {
1586 if (!o->show_all_errors)
1587 goto return_failed;
1588 ret = -1;
1589 }
1590 if (!ce_skip_worktree(ce))
1591 empty_worktree = 0;
1592
1593 }
1594 if (ret < 0)
1595 goto return_failed;
1596 /*
1597 * Sparse checkout is meant to narrow down checkout area
1598 * but it does not make sense to narrow down to empty working
1599 * tree. This is usually a mistake in sparse checkout rules.
1600 * Do not allow users to do that.
1601 */
1602 if (o->result.cache_nr && empty_worktree) {
1603 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1604 goto done;
1605 }
1606 }
1607
1608 ret = check_updates(o) ? (-2) : 0;
1609 if (o->dst_index) {
1610 move_index_extensions(&o->result, o->src_index);
1611 if (!ret) {
1612 if (git_env_bool("GIT_TEST_CHECK_CACHE_TREE", 0))
1613 cache_tree_verify(the_repository, &o->result);
1614 if (!o->result.cache_tree)
1615 o->result.cache_tree = cache_tree();
1616 if (!cache_tree_fully_valid(o->result.cache_tree))
1617 cache_tree_update(&o->result,
1618 WRITE_TREE_SILENT |
1619 WRITE_TREE_REPAIR);
1620 }
1621 discard_index(o->dst_index);
1622 *o->dst_index = o->result;
1623 } else {
1624 discard_index(&o->result);
1625 }
1626 o->src_index = NULL;
1627
1628 done:
1629 trace_performance_leave("unpack_trees");
1630 clear_exclude_list(&el);
1631 return ret;
1632
1633 return_failed:
1634 if (o->show_all_errors)
1635 display_error_msgs(o);
1636 mark_all_ce_unused(o->src_index);
1637 ret = unpack_failed(o, NULL);
1638 if (o->exiting_early)
1639 ret = 0;
1640 goto done;
1641 }
1642
1643 /* Here come the merge functions */
1644
1645 static int reject_merge(const struct cache_entry *ce,
1646 struct unpack_trees_options *o)
1647 {
1648 return o->gently ? -1 :
1649 add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1650 }
1651
1652 static int same(const struct cache_entry *a, const struct cache_entry *b)
1653 {
1654 if (!!a != !!b)
1655 return 0;
1656 if (!a && !b)
1657 return 1;
1658 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1659 return 0;
1660 return a->ce_mode == b->ce_mode &&
1661 oideq(&a->oid, &b->oid);
1662 }
1663
1664
1665 /*
1666 * When a CE gets turned into an unmerged entry, we
1667 * want it to be up-to-date
1668 */
1669 static int verify_uptodate_1(const struct cache_entry *ce,
1670 struct unpack_trees_options *o,
1671 enum unpack_trees_error_types error_type)
1672 {
1673 struct stat st;
1674
1675 if (o->index_only)
1676 return 0;
1677
1678 /*
1679 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1680 * if this entry is truly up-to-date because this file may be
1681 * overwritten.
1682 */
1683 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1684 ; /* keep checking */
1685 else if (o->reset || ce_uptodate(ce))
1686 return 0;
1687
1688 if (!lstat(ce->name, &st)) {
1689 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1690 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1691
1692 if (submodule_from_ce(ce)) {
1693 int r = check_submodule_move_head(ce,
1694 "HEAD", oid_to_hex(&ce->oid), o);
1695 if (r)
1696 return o->gently ? -1 :
1697 add_rejected_path(o, error_type, ce->name);
1698 return 0;
1699 }
1700
1701 if (!changed)
1702 return 0;
1703 /*
1704 * Historic default policy was to allow submodule to be out
1705 * of sync wrt the superproject index. If the submodule was
1706 * not considered interesting above, we don't care here.
1707 */
1708 if (S_ISGITLINK(ce->ce_mode))
1709 return 0;
1710
1711 errno = 0;
1712 }
1713 if (errno == ENOENT)
1714 return 0;
1715 return o->gently ? -1 :
1716 add_rejected_path(o, error_type, ce->name);
1717 }
1718
1719 int verify_uptodate(const struct cache_entry *ce,
1720 struct unpack_trees_options *o)
1721 {
1722 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1723 return 0;
1724 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1725 }
1726
1727 static int verify_uptodate_sparse(const struct cache_entry *ce,
1728 struct unpack_trees_options *o)
1729 {
1730 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1731 }
1732
1733 /*
1734 * TODO: We should actually invalidate o->result, not src_index [1].
1735 * But since cache tree and untracked cache both are not copied to
1736 * o->result until unpacking is complete, we invalidate them on
1737 * src_index instead with the assumption that they will be copied to
1738 * dst_index at the end.
1739 *
1740 * [1] src_index->cache_tree is also used in unpack_callback() so if
1741 * we invalidate o->result, we need to update it to use
1742 * o->result.cache_tree as well.
1743 */
1744 static void invalidate_ce_path(const struct cache_entry *ce,
1745 struct unpack_trees_options *o)
1746 {
1747 if (!ce)
1748 return;
1749 cache_tree_invalidate_path(o->src_index, ce->name);
1750 untracked_cache_invalidate_path(o->src_index, ce->name, 1);
1751 }
1752
1753 /*
1754 * Check that checking out ce->sha1 in subdir ce->name is not
1755 * going to overwrite any working files.
1756 *
1757 * Currently, git does not checkout subprojects during a superproject
1758 * checkout, so it is not going to overwrite anything.
1759 */
1760 static int verify_clean_submodule(const char *old_sha1,
1761 const struct cache_entry *ce,
1762 enum unpack_trees_error_types error_type,
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 enum unpack_trees_error_types error_type,
1774 struct unpack_trees_options *o)
1775 {
1776 /*
1777 * we are about to extract "ce->name"; we would not want to lose
1778 * anything in the existing directory there.
1779 */
1780 int namelen;
1781 int i;
1782 struct dir_struct d;
1783 char *pathbuf;
1784 int cnt = 0;
1785
1786 if (S_ISGITLINK(ce->ce_mode)) {
1787 struct object_id oid;
1788 int sub_head = resolve_gitlink_ref(ce->name, "HEAD", &oid);
1789 /*
1790 * If we are not going to update the submodule, then
1791 * we don't care.
1792 */
1793 if (!sub_head && oideq(&oid, &ce->oid))
1794 return 0;
1795 return verify_clean_submodule(sub_head ? NULL : oid_to_hex(&oid),
1796 ce, error_type, o);
1797 }
1798
1799 /*
1800 * First let's make sure we do not have a local modification
1801 * in that directory.
1802 */
1803 namelen = ce_namelen(ce);
1804 for (i = locate_in_src_index(ce, o);
1805 i < o->src_index->cache_nr;
1806 i++) {
1807 struct cache_entry *ce2 = o->src_index->cache[i];
1808 int len = ce_namelen(ce2);
1809 if (len < namelen ||
1810 strncmp(ce->name, ce2->name, namelen) ||
1811 ce2->name[namelen] != '/')
1812 break;
1813 /*
1814 * ce2->name is an entry in the subdirectory to be
1815 * removed.
1816 */
1817 if (!ce_stage(ce2)) {
1818 if (verify_uptodate(ce2, o))
1819 return -1;
1820 add_entry(o, ce2, CE_REMOVE, 0);
1821 invalidate_ce_path(ce, o);
1822 mark_ce_used(ce2, o);
1823 }
1824 cnt++;
1825 }
1826
1827 /*
1828 * Then we need to make sure that we do not lose a locally
1829 * present file that is not ignored.
1830 */
1831 pathbuf = xstrfmt("%.*s/", namelen, ce->name);
1832
1833 memset(&d, 0, sizeof(d));
1834 if (o->dir)
1835 d.exclude_per_dir = o->dir->exclude_per_dir;
1836 i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL);
1837 if (i)
1838 return o->gently ? -1 :
1839 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1840 free(pathbuf);
1841 return cnt;
1842 }
1843
1844 /*
1845 * This gets called when there was no index entry for the tree entry 'dst',
1846 * but we found a file in the working tree that 'lstat()' said was fine,
1847 * and we're on a case-insensitive filesystem.
1848 *
1849 * See if we can find a case-insensitive match in the index that also
1850 * matches the stat information, and assume it's that other file!
1851 */
1852 static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1853 {
1854 const struct cache_entry *src;
1855
1856 src = index_file_exists(o->src_index, name, len, 1);
1857 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1858 }
1859
1860 static int check_ok_to_remove(const char *name, int len, int dtype,
1861 const struct cache_entry *ce, struct stat *st,
1862 enum unpack_trees_error_types error_type,
1863 struct unpack_trees_options *o)
1864 {
1865 const struct cache_entry *result;
1866
1867 /*
1868 * It may be that the 'lstat()' succeeded even though
1869 * target 'ce' was absent, because there is an old
1870 * entry that is different only in case..
1871 *
1872 * Ignore that lstat() if it matches.
1873 */
1874 if (ignore_case && icase_exists(o, name, len, st))
1875 return 0;
1876
1877 if (o->dir &&
1878 is_excluded(o->dir, o->src_index, name, &dtype))
1879 /*
1880 * ce->name is explicitly excluded, so it is Ok to
1881 * overwrite it.
1882 */
1883 return 0;
1884 if (S_ISDIR(st->st_mode)) {
1885 /*
1886 * We are checking out path "foo" and
1887 * found "foo/." in the working tree.
1888 * This is tricky -- if we have modified
1889 * files that are in "foo/" we would lose
1890 * them.
1891 */
1892 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1893 return -1;
1894 return 0;
1895 }
1896
1897 /*
1898 * The previous round may already have decided to
1899 * delete this path, which is in a subdirectory that
1900 * is being replaced with a blob.
1901 */
1902 result = index_file_exists(&o->result, name, len, 0);
1903 if (result) {
1904 if (result->ce_flags & CE_REMOVE)
1905 return 0;
1906 }
1907
1908 return o->gently ? -1 :
1909 add_rejected_path(o, error_type, name);
1910 }
1911
1912 /*
1913 * We do not want to remove or overwrite a working tree file that
1914 * is not tracked, unless it is ignored.
1915 */
1916 static int verify_absent_1(const struct cache_entry *ce,
1917 enum unpack_trees_error_types error_type,
1918 struct unpack_trees_options *o)
1919 {
1920 int len;
1921 struct stat st;
1922
1923 if (o->index_only || o->reset || !o->update)
1924 return 0;
1925
1926 len = check_leading_path(ce->name, ce_namelen(ce));
1927 if (!len)
1928 return 0;
1929 else if (len > 0) {
1930 char *path;
1931 int ret;
1932
1933 path = xmemdupz(ce->name, len);
1934 if (lstat(path, &st))
1935 ret = error_errno("cannot stat '%s'", path);
1936 else {
1937 if (submodule_from_ce(ce))
1938 ret = check_submodule_move_head(ce,
1939 oid_to_hex(&ce->oid),
1940 NULL, o);
1941 else
1942 ret = check_ok_to_remove(path, len, DT_UNKNOWN, NULL,
1943 &st, error_type, o);
1944 }
1945 free(path);
1946 return ret;
1947 } else if (lstat(ce->name, &st)) {
1948 if (errno != ENOENT)
1949 return error_errno("cannot stat '%s'", ce->name);
1950 return 0;
1951 } else {
1952 if (submodule_from_ce(ce))
1953 return check_submodule_move_head(ce, oid_to_hex(&ce->oid),
1954 NULL, o);
1955
1956 return check_ok_to_remove(ce->name, ce_namelen(ce),
1957 ce_to_dtype(ce), ce, &st,
1958 error_type, o);
1959 }
1960 }
1961
1962 static int verify_absent(const struct cache_entry *ce,
1963 enum unpack_trees_error_types error_type,
1964 struct unpack_trees_options *o)
1965 {
1966 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1967 return 0;
1968 return verify_absent_1(ce, error_type, o);
1969 }
1970
1971 static int verify_absent_sparse(const struct cache_entry *ce,
1972 enum unpack_trees_error_types error_type,
1973 struct unpack_trees_options *o)
1974 {
1975 enum unpack_trees_error_types orphaned_error = error_type;
1976 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1977 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1978
1979 return verify_absent_1(ce, orphaned_error, o);
1980 }
1981
1982 static int merged_entry(const struct cache_entry *ce,
1983 const struct cache_entry *old,
1984 struct unpack_trees_options *o)
1985 {
1986 int update = CE_UPDATE;
1987 struct cache_entry *merge = dup_cache_entry(ce, &o->result);
1988
1989 if (!old) {
1990 /*
1991 * New index entries. In sparse checkout, the following
1992 * verify_absent() will be delayed until after
1993 * traverse_trees() finishes in unpack_trees(), then:
1994 *
1995 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1996 * - verify_absent() be called again, this time with
1997 * correct CE_NEW_SKIP_WORKTREE
1998 *
1999 * verify_absent() call here does nothing in sparse
2000 * checkout (i.e. o->skip_sparse_checkout == 0)
2001 */
2002 update |= CE_ADDED;
2003 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
2004
2005 if (verify_absent(merge,
2006 ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
2007 discard_cache_entry(merge);
2008 return -1;
2009 }
2010 invalidate_ce_path(merge, o);
2011
2012 if (submodule_from_ce(ce)) {
2013 int ret = check_submodule_move_head(ce, NULL,
2014 oid_to_hex(&ce->oid),
2015 o);
2016 if (ret)
2017 return ret;
2018 }
2019
2020 } else if (!(old->ce_flags & CE_CONFLICTED)) {
2021 /*
2022 * See if we can re-use the old CE directly?
2023 * That way we get the uptodate stat info.
2024 *
2025 * This also removes the UPDATE flag on a match; otherwise
2026 * we will end up overwriting local changes in the work tree.
2027 */
2028 if (same(old, merge)) {
2029 copy_cache_entry(merge, old);
2030 update = 0;
2031 } else {
2032 if (verify_uptodate(old, o)) {
2033 discard_cache_entry(merge);
2034 return -1;
2035 }
2036 /* Migrate old flags over */
2037 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
2038 invalidate_ce_path(old, o);
2039 }
2040
2041 if (submodule_from_ce(ce)) {
2042 int ret = check_submodule_move_head(ce, oid_to_hex(&old->oid),
2043 oid_to_hex(&ce->oid),
2044 o);
2045 if (ret)
2046 return ret;
2047 }
2048 } else {
2049 /*
2050 * Previously unmerged entry left as an existence
2051 * marker by read_index_unmerged();
2052 */
2053 invalidate_ce_path(old, o);
2054 }
2055
2056 do_add_entry(o, merge, update, CE_STAGEMASK);
2057 return 1;
2058 }
2059
2060 static int deleted_entry(const struct cache_entry *ce,
2061 const struct cache_entry *old,
2062 struct unpack_trees_options *o)
2063 {
2064 /* Did it exist in the index? */
2065 if (!old) {
2066 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2067 return -1;
2068 return 0;
2069 }
2070 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
2071 return -1;
2072 add_entry(o, ce, CE_REMOVE, 0);
2073 invalidate_ce_path(ce, o);
2074 return 1;
2075 }
2076
2077 static int keep_entry(const struct cache_entry *ce,
2078 struct unpack_trees_options *o)
2079 {
2080 add_entry(o, ce, 0, 0);
2081 if (ce_stage(ce))
2082 invalidate_ce_path(ce, o);
2083 return 1;
2084 }
2085
2086 #if DBRT_DEBUG
2087 static void show_stage_entry(FILE *o,
2088 const char *label, const struct cache_entry *ce)
2089 {
2090 if (!ce)
2091 fprintf(o, "%s (missing)\n", label);
2092 else
2093 fprintf(o, "%s%06o %s %d\t%s\n",
2094 label,
2095 ce->ce_mode,
2096 oid_to_hex(&ce->oid),
2097 ce_stage(ce),
2098 ce->name);
2099 }
2100 #endif
2101
2102 int threeway_merge(const struct cache_entry * const *stages,
2103 struct unpack_trees_options *o)
2104 {
2105 const struct cache_entry *index;
2106 const struct cache_entry *head;
2107 const struct cache_entry *remote = stages[o->head_idx + 1];
2108 int count;
2109 int head_match = 0;
2110 int remote_match = 0;
2111
2112 int df_conflict_head = 0;
2113 int df_conflict_remote = 0;
2114
2115 int any_anc_missing = 0;
2116 int no_anc_exists = 1;
2117 int i;
2118
2119 for (i = 1; i < o->head_idx; i++) {
2120 if (!stages[i] || stages[i] == o->df_conflict_entry)
2121 any_anc_missing = 1;
2122 else
2123 no_anc_exists = 0;
2124 }
2125
2126 index = stages[0];
2127 head = stages[o->head_idx];
2128
2129 if (head == o->df_conflict_entry) {
2130 df_conflict_head = 1;
2131 head = NULL;
2132 }
2133
2134 if (remote == o->df_conflict_entry) {
2135 df_conflict_remote = 1;
2136 remote = NULL;
2137 }
2138
2139 /*
2140 * First, if there's a #16 situation, note that to prevent #13
2141 * and #14.
2142 */
2143 if (!same(remote, head)) {
2144 for (i = 1; i < o->head_idx; i++) {
2145 if (same(stages[i], head)) {
2146 head_match = i;
2147 }
2148 if (same(stages[i], remote)) {
2149 remote_match = i;
2150 }
2151 }
2152 }
2153
2154 /*
2155 * We start with cases where the index is allowed to match
2156 * something other than the head: #14(ALT) and #2ALT, where it
2157 * is permitted to match the result instead.
2158 */
2159 /* #14, #14ALT, #2ALT */
2160 if (remote && !df_conflict_head && head_match && !remote_match) {
2161 if (index && !same(index, remote) && !same(index, head))
2162 return reject_merge(index, o);
2163 return merged_entry(remote, index, o);
2164 }
2165 /*
2166 * If we have an entry in the index cache, then we want to
2167 * make sure that it matches head.
2168 */
2169 if (index && !same(index, head))
2170 return reject_merge(index, o);
2171
2172 if (head) {
2173 /* #5ALT, #15 */
2174 if (same(head, remote))
2175 return merged_entry(head, index, o);
2176 /* #13, #3ALT */
2177 if (!df_conflict_remote && remote_match && !head_match)
2178 return merged_entry(head, index, o);
2179 }
2180
2181 /* #1 */
2182 if (!head && !remote && any_anc_missing)
2183 return 0;
2184
2185 /*
2186 * Under the "aggressive" rule, we resolve mostly trivial
2187 * cases that we historically had git-merge-one-file resolve.
2188 */
2189 if (o->aggressive) {
2190 int head_deleted = !head;
2191 int remote_deleted = !remote;
2192 const struct cache_entry *ce = NULL;
2193
2194 if (index)
2195 ce = index;
2196 else if (head)
2197 ce = head;
2198 else if (remote)
2199 ce = remote;
2200 else {
2201 for (i = 1; i < o->head_idx; i++) {
2202 if (stages[i] && stages[i] != o->df_conflict_entry) {
2203 ce = stages[i];
2204 break;
2205 }
2206 }
2207 }
2208
2209 /*
2210 * Deleted in both.
2211 * Deleted in one and unchanged in the other.
2212 */
2213 if ((head_deleted && remote_deleted) ||
2214 (head_deleted && remote && remote_match) ||
2215 (remote_deleted && head && head_match)) {
2216 if (index)
2217 return deleted_entry(index, index, o);
2218 if (ce && !head_deleted) {
2219 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
2220 return -1;
2221 }
2222 return 0;
2223 }
2224 /*
2225 * Added in both, identically.
2226 */
2227 if (no_anc_exists && head && remote && same(head, remote))
2228 return merged_entry(head, index, o);
2229
2230 }
2231
2232 /* Below are "no merge" cases, which require that the index be
2233 * up-to-date to avoid the files getting overwritten with
2234 * conflict resolution files.
2235 */
2236 if (index) {
2237 if (verify_uptodate(index, o))
2238 return -1;
2239 }
2240
2241 o->nontrivial_merge = 1;
2242
2243 /* #2, #3, #4, #6, #7, #9, #10, #11. */
2244 count = 0;
2245 if (!head_match || !remote_match) {
2246 for (i = 1; i < o->head_idx; i++) {
2247 if (stages[i] && stages[i] != o->df_conflict_entry) {
2248 keep_entry(stages[i], o);
2249 count++;
2250 break;
2251 }
2252 }
2253 }
2254 #if DBRT_DEBUG
2255 else {
2256 fprintf(stderr, "read-tree: warning #16 detected\n");
2257 show_stage_entry(stderr, "head ", stages[head_match]);
2258 show_stage_entry(stderr, "remote ", stages[remote_match]);
2259 }
2260 #endif
2261 if (head) { count += keep_entry(head, o); }
2262 if (remote) { count += keep_entry(remote, o); }
2263 return count;
2264 }
2265
2266 /*
2267 * Two-way merge.
2268 *
2269 * The rule is to "carry forward" what is in the index without losing
2270 * information across a "fast-forward", favoring a successful merge
2271 * over a merge failure when it makes sense. For details of the
2272 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
2273 *
2274 */
2275 int twoway_merge(const struct cache_entry * const *src,
2276 struct unpack_trees_options *o)
2277 {
2278 const struct cache_entry *current = src[0];
2279 const struct cache_entry *oldtree = src[1];
2280 const struct cache_entry *newtree = src[2];
2281
2282 if (o->merge_size != 2)
2283 return error("Cannot do a twoway merge of %d trees",
2284 o->merge_size);
2285
2286 if (oldtree == o->df_conflict_entry)
2287 oldtree = NULL;
2288 if (newtree == o->df_conflict_entry)
2289 newtree = NULL;
2290
2291 if (current) {
2292 if (current->ce_flags & CE_CONFLICTED) {
2293 if (same(oldtree, newtree) || o->reset) {
2294 if (!newtree)
2295 return deleted_entry(current, current, o);
2296 else
2297 return merged_entry(newtree, current, o);
2298 }
2299 return reject_merge(current, o);
2300 } else if ((!oldtree && !newtree) || /* 4 and 5 */
2301 (!oldtree && newtree &&
2302 same(current, newtree)) || /* 6 and 7 */
2303 (oldtree && newtree &&
2304 same(oldtree, newtree)) || /* 14 and 15 */
2305 (oldtree && newtree &&
2306 !same(oldtree, newtree) && /* 18 and 19 */
2307 same(current, newtree))) {
2308 return keep_entry(current, o);
2309 } else if (oldtree && !newtree && same(current, oldtree)) {
2310 /* 10 or 11 */
2311 return deleted_entry(oldtree, current, o);
2312 } else if (oldtree && newtree &&
2313 same(current, oldtree) && !same(current, newtree)) {
2314 /* 20 or 21 */
2315 return merged_entry(newtree, current, o);
2316 } else
2317 return reject_merge(current, o);
2318 }
2319 else if (newtree) {
2320 if (oldtree && !o->initial_checkout) {
2321 /*
2322 * deletion of the path was staged;
2323 */
2324 if (same(oldtree, newtree))
2325 return 1;
2326 return reject_merge(oldtree, o);
2327 }
2328 return merged_entry(newtree, current, o);
2329 }
2330 return deleted_entry(oldtree, current, o);
2331 }
2332
2333 /*
2334 * Bind merge.
2335 *
2336 * Keep the index entries at stage0, collapse stage1 but make sure
2337 * stage0 does not have anything there.
2338 */
2339 int bind_merge(const struct cache_entry * const *src,
2340 struct unpack_trees_options *o)
2341 {
2342 const struct cache_entry *old = src[0];
2343 const struct cache_entry *a = src[1];
2344
2345 if (o->merge_size != 1)
2346 return error("Cannot do a bind merge of %d trees",
2347 o->merge_size);
2348 if (a && old)
2349 return o->gently ? -1 :
2350 error(ERRORMSG(o, ERROR_BIND_OVERLAP),
2351 super_prefixed(a->name),
2352 super_prefixed(old->name));
2353 if (!a)
2354 return keep_entry(old, o);
2355 else
2356 return merged_entry(a, NULL, o);
2357 }
2358
2359 /*
2360 * One-way merge.
2361 *
2362 * The rule is:
2363 * - take the stat information from stage0, take the data from stage1
2364 */
2365 int oneway_merge(const struct cache_entry * const *src,
2366 struct unpack_trees_options *o)
2367 {
2368 const struct cache_entry *old = src[0];
2369 const struct cache_entry *a = src[1];
2370
2371 if (o->merge_size != 1)
2372 return error("Cannot do a oneway merge of %d trees",
2373 o->merge_size);
2374
2375 if (!a || a == o->df_conflict_entry)
2376 return deleted_entry(old, old, o);
2377
2378 if (old && same(old, a)) {
2379 int update = 0;
2380 if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
2381 struct stat st;
2382 if (lstat(old->name, &st) ||
2383 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
2384 update |= CE_UPDATE;
2385 }
2386 if (o->update && S_ISGITLINK(old->ce_mode) &&
2387 should_update_submodules() && !verify_uptodate(old, o))
2388 update |= CE_UPDATE;
2389 add_entry(o, old, update, 0);
2390 return 0;
2391 }
2392 return merged_entry(a, old, o);
2393 }