commit: allow parse_commit* to handle any repo
[git/git.git] / commit-reach.c
CommitLineData
5227c385 1#include "cache.h"
5227c385 2#include "commit.h"
920f93ca 3#include "commit-graph.h"
1d614d41
DS
4#include "decorate.h"
5#include "prio-queue.h"
6#include "tree.h"
6621c838 7#include "ref-filter.h"
1d614d41
DS
8#include "revision.h"
9#include "tag.h"
5227c385
DS
10#include "commit-reach.h"
11
12/* Remember to update object flag allocation in object.h */
ba3ca1ed 13#define REACHABLE (1u<<15)
5227c385
DS
14#define PARENT1 (1u<<16)
15#define PARENT2 (1u<<17)
16#define STALE (1u<<18)
17#define RESULT (1u<<19)
18
19static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
20
21static int queue_has_nonstale(struct prio_queue *queue)
22{
23 int i;
24 for (i = 0; i < queue->nr; i++) {
25 struct commit *commit = queue->array[i].data;
26 if (!(commit->object.flags & STALE))
27 return 1;
28 }
29 return 0;
30}
31
32/* all input commits in one and twos[] must have been parsed! */
33static struct commit_list *paint_down_to_common(struct commit *one, int n,
34 struct commit **twos,
35 int min_generation)
36{
37 struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
38 struct commit_list *result = NULL;
39 int i;
40 uint32_t last_gen = GENERATION_NUMBER_INFINITY;
41
1b7a91da
JH
42 if (!min_generation)
43 queue.compare = compare_commits_by_commit_date;
44
5227c385
DS
45 one->object.flags |= PARENT1;
46 if (!n) {
47 commit_list_append(one, &result);
48 return result;
49 }
50 prio_queue_put(&queue, one);
51
52 for (i = 0; i < n; i++) {
53 twos[i]->object.flags |= PARENT2;
54 prio_queue_put(&queue, twos[i]);
55 }
56
57 while (queue_has_nonstale(&queue)) {
58 struct commit *commit = prio_queue_get(&queue);
59 struct commit_list *parents;
60 int flags;
61
1b7a91da 62 if (min_generation && commit->generation > last_gen)
5227c385
DS
63 BUG("bad generation skip %8x > %8x at %s",
64 commit->generation, last_gen,
65 oid_to_hex(&commit->object.oid));
66 last_gen = commit->generation;
67
68 if (commit->generation < min_generation)
69 break;
70
71 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
72 if (flags == (PARENT1 | PARENT2)) {
73 if (!(commit->object.flags & RESULT)) {
74 commit->object.flags |= RESULT;
75 commit_list_insert_by_date(commit, &result);
76 }
77 /* Mark parents of a found merge stale */
78 flags |= STALE;
79 }
80 parents = commit->parents;
81 while (parents) {
82 struct commit *p = parents->item;
83 parents = parents->next;
84 if ((p->object.flags & flags) == flags)
85 continue;
86 if (parse_commit(p))
87 return NULL;
88 p->object.flags |= flags;
89 prio_queue_put(&queue, p);
90 }
91 }
92
93 clear_prio_queue(&queue);
94 return result;
95}
96
97static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
98{
99 struct commit_list *list = NULL;
100 struct commit_list *result = NULL;
101 int i;
102
103 for (i = 0; i < n; i++) {
104 if (one == twos[i])
105 /*
106 * We do not mark this even with RESULT so we do not
107 * have to clean it up.
108 */
109 return commit_list_insert(one, &result);
110 }
111
112 if (parse_commit(one))
113 return NULL;
114 for (i = 0; i < n; i++) {
115 if (parse_commit(twos[i]))
116 return NULL;
117 }
118
119 list = paint_down_to_common(one, n, twos, 0);
120
121 while (list) {
122 struct commit *commit = pop_commit(&list);
123 if (!(commit->object.flags & STALE))
124 commit_list_insert_by_date(commit, &result);
125 }
126 return result;
127}
128
129struct commit_list *get_octopus_merge_bases(struct commit_list *in)
130{
131 struct commit_list *i, *j, *k, *ret = NULL;
132
133 if (!in)
134 return ret;
135
136 commit_list_insert(in->item, &ret);
137
138 for (i = in->next; i; i = i->next) {
139 struct commit_list *new_commits = NULL, *end = NULL;
140
141 for (j = ret; j; j = j->next) {
142 struct commit_list *bases;
143 bases = get_merge_bases(i->item, j->item);
144 if (!new_commits)
145 new_commits = bases;
146 else
147 end->next = bases;
148 for (k = bases; k; k = k->next)
149 end = k;
150 }
151 ret = new_commits;
152 }
153 return ret;
154}
155
156static int remove_redundant(struct commit **array, int cnt)
157{
158 /*
159 * Some commit in the array may be an ancestor of
160 * another commit. Move such commit to the end of
161 * the array, and return the number of commits that
162 * are independent from each other.
163 */
164 struct commit **work;
165 unsigned char *redundant;
166 int *filled_index;
167 int i, j, filled;
168
169 work = xcalloc(cnt, sizeof(*work));
170 redundant = xcalloc(cnt, 1);
171 ALLOC_ARRAY(filled_index, cnt - 1);
172
173 for (i = 0; i < cnt; i++)
174 parse_commit(array[i]);
175 for (i = 0; i < cnt; i++) {
176 struct commit_list *common;
177 uint32_t min_generation = array[i]->generation;
178
179 if (redundant[i])
180 continue;
181 for (j = filled = 0; j < cnt; j++) {
182 if (i == j || redundant[j])
183 continue;
184 filled_index[filled] = j;
185 work[filled++] = array[j];
186
187 if (array[j]->generation < min_generation)
188 min_generation = array[j]->generation;
189 }
190 common = paint_down_to_common(array[i], filled, work,
191 min_generation);
192 if (array[i]->object.flags & PARENT2)
193 redundant[i] = 1;
194 for (j = 0; j < filled; j++)
195 if (work[j]->object.flags & PARENT1)
196 redundant[filled_index[j]] = 1;
197 clear_commit_marks(array[i], all_flags);
198 clear_commit_marks_many(filled, work, all_flags);
199 free_commit_list(common);
200 }
201
202 /* Now collect the result */
203 COPY_ARRAY(work, array, cnt);
204 for (i = filled = 0; i < cnt; i++)
205 if (!redundant[i])
206 array[filled++] = work[i];
207 for (j = filled, i = 0; i < cnt; i++)
208 if (redundant[i])
209 array[j++] = work[i];
210 free(work);
211 free(redundant);
212 free(filled_index);
213 return filled;
214}
215
216static struct commit_list *get_merge_bases_many_0(struct commit *one,
217 int n,
218 struct commit **twos,
219 int cleanup)
220{
221 struct commit_list *list;
222 struct commit **rslt;
223 struct commit_list *result;
224 int cnt, i;
225
226 result = merge_bases_many(one, n, twos);
227 for (i = 0; i < n; i++) {
228 if (one == twos[i])
229 return result;
230 }
231 if (!result || !result->next) {
232 if (cleanup) {
233 clear_commit_marks(one, all_flags);
234 clear_commit_marks_many(n, twos, all_flags);
235 }
236 return result;
237 }
238
239 /* There are more than one */
240 cnt = commit_list_count(result);
241 rslt = xcalloc(cnt, sizeof(*rslt));
242 for (list = result, i = 0; list; list = list->next)
243 rslt[i++] = list->item;
244 free_commit_list(result);
245
246 clear_commit_marks(one, all_flags);
247 clear_commit_marks_many(n, twos, all_flags);
248
249 cnt = remove_redundant(rslt, cnt);
250 result = NULL;
251 for (i = 0; i < cnt; i++)
252 commit_list_insert_by_date(rslt[i], &result);
253 free(rslt);
254 return result;
255}
256
257struct commit_list *get_merge_bases_many(struct commit *one,
258 int n,
259 struct commit **twos)
260{
261 return get_merge_bases_many_0(one, n, twos, 1);
262}
263
264struct commit_list *get_merge_bases_many_dirty(struct commit *one,
265 int n,
266 struct commit **twos)
267{
268 return get_merge_bases_many_0(one, n, twos, 0);
269}
270
271struct commit_list *get_merge_bases(struct commit *one, struct commit *two)
272{
273 return get_merge_bases_many_0(one, 1, &two, 1);
274}
275
276/*
277 * Is "commit" a descendant of one of the elements on the "with_commit" list?
278 */
279int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
280{
281 if (!with_commit)
282 return 1;
5227c385 283
6cc01743
DS
284 if (generation_numbers_enabled(the_repository)) {
285 struct commit_list *from_list = NULL;
286 int result;
287 commit_list_insert(commit, &from_list);
288 result = can_all_from_reach(from_list, with_commit, 0);
289 free_commit_list(from_list);
290 return result;
291 } else {
292 while (with_commit) {
293 struct commit *other;
294
295 other = with_commit->item;
296 with_commit = with_commit->next;
297 if (in_merge_bases(other, commit))
298 return 1;
299 }
300 return 0;
5227c385 301 }
5227c385
DS
302}
303
304/*
305 * Is "commit" an ancestor of one of the "references"?
306 */
307int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
308{
309 struct commit_list *bases;
310 int ret = 0, i;
311 uint32_t min_generation = GENERATION_NUMBER_INFINITY;
312
313 if (parse_commit(commit))
314 return ret;
315 for (i = 0; i < nr_reference; i++) {
316 if (parse_commit(reference[i]))
317 return ret;
318 if (reference[i]->generation < min_generation)
319 min_generation = reference[i]->generation;
320 }
321
322 if (commit->generation > min_generation)
323 return ret;
324
325 bases = paint_down_to_common(commit, nr_reference, reference, commit->generation);
326 if (commit->object.flags & PARENT2)
327 ret = 1;
328 clear_commit_marks(commit, all_flags);
329 clear_commit_marks_many(nr_reference, reference, all_flags);
330 free_commit_list(bases);
331 return ret;
332}
333
334/*
335 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
336 */
337int in_merge_bases(struct commit *commit, struct commit *reference)
338{
339 return in_merge_bases_many(commit, 1, &reference);
340}
341
342struct commit_list *reduce_heads(struct commit_list *heads)
343{
344 struct commit_list *p;
345 struct commit_list *result = NULL, **tail = &result;
346 struct commit **array;
347 int num_head, i;
348
349 if (!heads)
350 return NULL;
351
352 /* Uniquify */
353 for (p = heads; p; p = p->next)
354 p->item->object.flags &= ~STALE;
355 for (p = heads, num_head = 0; p; p = p->next) {
356 if (p->item->object.flags & STALE)
357 continue;
358 p->item->object.flags |= STALE;
359 num_head++;
360 }
361 array = xcalloc(num_head, sizeof(*array));
362 for (p = heads, i = 0; p; p = p->next) {
363 if (p->item->object.flags & STALE) {
364 array[i++] = p->item;
365 p->item->object.flags &= ~STALE;
366 }
367 }
368 num_head = remove_redundant(array, num_head);
369 for (i = 0; i < num_head; i++)
370 tail = &commit_list_insert(array[i], tail)->next;
371 free(array);
372 return result;
373}
374
375void reduce_heads_replace(struct commit_list **heads)
376{
377 struct commit_list *result = reduce_heads(*heads);
378 free_commit_list(*heads);
379 *heads = result;
380}
1d614d41 381
1d614d41
DS
382int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
383{
384 struct object *o;
385 struct commit *old_commit, *new_commit;
1e3497a2 386 struct commit_list *old_commit_list = NULL;
1d614d41
DS
387
388 /*
389 * Both new_commit and old_commit must be commit-ish and new_commit is descendant of
390 * old_commit. Otherwise we require --force.
391 */
392 o = deref_tag(the_repository, parse_object(the_repository, old_oid),
393 NULL, 0);
394 if (!o || o->type != OBJ_COMMIT)
395 return 0;
396 old_commit = (struct commit *) o;
397
398 o = deref_tag(the_repository, parse_object(the_repository, new_oid),
399 NULL, 0);
400 if (!o || o->type != OBJ_COMMIT)
401 return 0;
402 new_commit = (struct commit *) o;
403
404 if (parse_commit(new_commit) < 0)
405 return 0;
406
1e3497a2
DS
407 commit_list_insert(old_commit, &old_commit_list);
408 return is_descendant_of(new_commit, old_commit_list);
1d614d41 409}
920f93ca
DS
410
411/*
412 * Mimicking the real stack, this stack lives on the heap, avoiding stack
413 * overflows.
414 *
415 * At each recursion step, the stack items points to the commits whose
416 * ancestors are to be inspected.
417 */
418struct contains_stack {
419 int nr, alloc;
420 struct contains_stack_entry {
421 struct commit *commit;
422 struct commit_list *parents;
423 } *contains_stack;
424};
425
426static int in_commit_list(const struct commit_list *want, struct commit *c)
427{
428 for (; want; want = want->next)
e43d2dcc 429 if (oideq(&want->item->object.oid, &c->object.oid))
920f93ca
DS
430 return 1;
431 return 0;
432}
433
434/*
435 * Test whether the candidate is contained in the list.
436 * Do not recurse to find out, though, but return -1 if inconclusive.
437 */
438static enum contains_result contains_test(struct commit *candidate,
439 const struct commit_list *want,
440 struct contains_cache *cache,
441 uint32_t cutoff)
442{
443 enum contains_result *cached = contains_cache_at(cache, candidate);
444
445 /* If we already have the answer cached, return that. */
446 if (*cached)
447 return *cached;
448
449 /* or are we it? */
450 if (in_commit_list(want, candidate)) {
451 *cached = CONTAINS_YES;
452 return CONTAINS_YES;
453 }
454
455 /* Otherwise, we don't know; prepare to recurse */
456 parse_commit_or_die(candidate);
457
458 if (candidate->generation < cutoff)
459 return CONTAINS_NO;
460
461 return CONTAINS_UNKNOWN;
462}
463
464static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
465{
466 ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
467 contains_stack->contains_stack[contains_stack->nr].commit = candidate;
468 contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
469}
470
471static enum contains_result contains_tag_algo(struct commit *candidate,
472 const struct commit_list *want,
473 struct contains_cache *cache)
474{
475 struct contains_stack contains_stack = { 0, 0, NULL };
476 enum contains_result result;
477 uint32_t cutoff = GENERATION_NUMBER_INFINITY;
478 const struct commit_list *p;
479
480 for (p = want; p; p = p->next) {
481 struct commit *c = p->item;
482 load_commit_graph_info(the_repository, c);
483 if (c->generation < cutoff)
484 cutoff = c->generation;
485 }
486
487 result = contains_test(candidate, want, cache, cutoff);
488 if (result != CONTAINS_UNKNOWN)
489 return result;
490
491 push_to_contains_stack(candidate, &contains_stack);
492 while (contains_stack.nr) {
493 struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
494 struct commit *commit = entry->commit;
495 struct commit_list *parents = entry->parents;
496
497 if (!parents) {
498 *contains_cache_at(cache, commit) = CONTAINS_NO;
499 contains_stack.nr--;
500 }
501 /*
502 * If we just popped the stack, parents->item has been marked,
503 * therefore contains_test will return a meaningful yes/no.
504 */
505 else switch (contains_test(parents->item, want, cache, cutoff)) {
506 case CONTAINS_YES:
507 *contains_cache_at(cache, commit) = CONTAINS_YES;
508 contains_stack.nr--;
509 break;
510 case CONTAINS_NO:
511 entry->parents = parents->next;
512 break;
513 case CONTAINS_UNKNOWN:
514 push_to_contains_stack(parents->item, &contains_stack);
515 break;
516 }
517 }
518 free(contains_stack.contains_stack);
519 return contains_test(candidate, want, cache, cutoff);
520}
521
522int commit_contains(struct ref_filter *filter, struct commit *commit,
523 struct commit_list *list, struct contains_cache *cache)
524{
525 if (filter->with_commit_tag_algo)
526 return contains_tag_algo(commit, list, cache) == CONTAINS_YES;
527 return is_descendant_of(commit, list);
528}
ba3ca1ed 529
4fbcca4e 530static int compare_commits_by_gen(const void *_a, const void *_b)
ba3ca1ed 531{
4fbcca4e
DS
532 const struct commit *a = (const struct commit *)_a;
533 const struct commit *b = (const struct commit *)_b;
ba3ca1ed 534
4fbcca4e
DS
535 if (a->generation < b->generation)
536 return -1;
537 if (a->generation > b->generation)
538 return 1;
539 return 0;
ba3ca1ed
DS
540}
541
542int can_all_from_reach_with_flag(struct object_array *from,
543 unsigned int with_flag,
544 unsigned int assign_flag,
4fbcca4e
DS
545 time_t min_commit_date,
546 uint32_t min_generation)
ba3ca1ed 547{
4fbcca4e 548 struct commit **list = NULL;
ba3ca1ed 549 int i;
b67f6b26 550 int nr_commits;
4fbcca4e 551 int result = 1;
ba3ca1ed 552
4fbcca4e 553 ALLOC_ARRAY(list, from->nr);
b67f6b26 554 nr_commits = 0;
ba3ca1ed 555 for (i = 0; i < from->nr; i++) {
b67f6b26 556 struct object *from_one = from->objects[i].item;
ba3ca1ed 557
b67f6b26
DS
558 if (!from_one || from_one->flags & assign_flag)
559 continue;
560
561 from_one = deref_tag(the_repository, from_one,
562 "a from object", 0);
563 if (!from_one || from_one->type != OBJ_COMMIT) {
85806440
DS
564 /*
565 * no way to tell if this is reachable by
b67f6b26
DS
566 * looking at the ancestry chain alone, so
567 * leave a note to ourselves not to worry about
568 * this object anymore.
569 */
570 from->objects[i].item->flags |= assign_flag;
571 continue;
572 }
573
574 list[nr_commits] = (struct commit *)from_one;
575 if (parse_commit(list[nr_commits]) ||
576 list[nr_commits]->generation < min_generation) {
577 result = 0;
578 goto cleanup;
579 }
580
581 nr_commits++;
ba3ca1ed 582 }
4fbcca4e 583
b67f6b26 584 QSORT(list, nr_commits, compare_commits_by_gen);
4fbcca4e 585
b67f6b26 586 for (i = 0; i < nr_commits; i++) {
4fbcca4e
DS
587 /* DFS from list[i] */
588 struct commit_list *stack = NULL;
589
590 list[i]->object.flags |= assign_flag;
591 commit_list_insert(list[i], &stack);
592
593 while (stack) {
594 struct commit_list *parent;
595
596 if (stack->item->object.flags & with_flag) {
597 pop_commit(&stack);
598 continue;
599 }
600
601 for (parent = stack->item->parents; parent; parent = parent->next) {
602 if (parent->item->object.flags & (with_flag | RESULT))
603 stack->item->object.flags |= RESULT;
604
605 if (!(parent->item->object.flags & assign_flag)) {
606 parent->item->object.flags |= assign_flag;
607
608 if (parse_commit(parent->item) ||
609 parent->item->date < min_commit_date ||
610 parent->item->generation < min_generation)
611 continue;
612
613 commit_list_insert(parent->item, &stack);
614 break;
615 }
616 }
617
618 if (!parent)
619 pop_commit(&stack);
620 }
621
622 if (!(list[i]->object.flags & (with_flag | RESULT))) {
623 result = 0;
624 goto cleanup;
625 }
626 }
627
628cleanup:
85806440 629 clear_commit_marks_many(nr_commits, list, RESULT | assign_flag);
4067a646
DS
630 free(list);
631
632 for (i = 0; i < from->nr; i++)
633 from->objects[i].item->flags &= ~assign_flag;
634
4fbcca4e 635 return result;
ba3ca1ed 636}
1792bc12
DS
637
638int can_all_from_reach(struct commit_list *from, struct commit_list *to,
639 int cutoff_by_min_date)
640{
641 struct object_array from_objs = OBJECT_ARRAY_INIT;
642 time_t min_commit_date = cutoff_by_min_date ? from->item->date : 0;
643 struct commit_list *from_iter = from, *to_iter = to;
644 int result;
4fbcca4e 645 uint32_t min_generation = GENERATION_NUMBER_INFINITY;
1792bc12
DS
646
647 while (from_iter) {
648 add_object_array(&from_iter->item->object, NULL, &from_objs);
649
650 if (!parse_commit(from_iter->item)) {
651 if (from_iter->item->date < min_commit_date)
652 min_commit_date = from_iter->item->date;
4fbcca4e
DS
653
654 if (from_iter->item->generation < min_generation)
655 min_generation = from_iter->item->generation;
1792bc12
DS
656 }
657
658 from_iter = from_iter->next;
659 }
660
661 while (to_iter) {
662 if (!parse_commit(to_iter->item)) {
663 if (to_iter->item->date < min_commit_date)
664 min_commit_date = to_iter->item->date;
4fbcca4e
DS
665
666 if (to_iter->item->generation < min_generation)
667 min_generation = to_iter->item->generation;
1792bc12
DS
668 }
669
670 to_iter->item->object.flags |= PARENT2;
671
672 to_iter = to_iter->next;
673 }
674
675 result = can_all_from_reach_with_flag(&from_objs, PARENT2, PARENT1,
4fbcca4e 676 min_commit_date, min_generation);
1792bc12
DS
677
678 while (from) {
679 clear_commit_marks(from->item, PARENT1);
680 from = from->next;
681 }
682
683 while (to) {
684 clear_commit_marks(to->item, PARENT2);
685 to = to->next;
686 }
687
688 object_array_clear(&from_objs);
689 return result;
690}