color: add support for 12-bit RGB colors
[alt-git.git] / commit-reach.c
blob8f9b008f876787abf12ca89af5541f0b3bdf6ba7
1 #include "git-compat-util.h"
2 #include "commit.h"
3 #include "commit-graph.h"
4 #include "decorate.h"
5 #include "hex.h"
6 #include "prio-queue.h"
7 #include "ref-filter.h"
8 #include "revision.h"
9 #include "tag.h"
10 #include "commit-reach.h"
11 #include "ewah/ewok.h"
13 /* Remember to update object flag allocation in object.h */
14 #define PARENT1 (1u<<16)
15 #define PARENT2 (1u<<17)
16 #define STALE (1u<<18)
17 #define RESULT (1u<<19)
19 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
21 static int compare_commits_by_gen(const void *_a, const void *_b)
23 const struct commit *a = *(const struct commit * const *)_a;
24 const struct commit *b = *(const struct commit * const *)_b;
26 timestamp_t generation_a = commit_graph_generation(a);
27 timestamp_t generation_b = commit_graph_generation(b);
29 if (generation_a < generation_b)
30 return -1;
31 if (generation_a > generation_b)
32 return 1;
33 if (a->date < b->date)
34 return -1;
35 if (a->date > b->date)
36 return 1;
37 return 0;
40 static int queue_has_nonstale(struct prio_queue *queue)
42 int i;
43 for (i = 0; i < queue->nr; i++) {
44 struct commit *commit = queue->array[i].data;
45 if (!(commit->object.flags & STALE))
46 return 1;
48 return 0;
51 /* all input commits in one and twos[] must have been parsed! */
52 static int paint_down_to_common(struct repository *r,
53 struct commit *one, int n,
54 struct commit **twos,
55 timestamp_t min_generation,
56 int ignore_missing_commits,
57 struct commit_list **result)
59 struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
60 int i;
61 timestamp_t last_gen = GENERATION_NUMBER_INFINITY;
63 if (!min_generation && !corrected_commit_dates_enabled(r))
64 queue.compare = compare_commits_by_commit_date;
66 one->object.flags |= PARENT1;
67 if (!n) {
68 commit_list_append(one, result);
69 return 0;
71 prio_queue_put(&queue, one);
73 for (i = 0; i < n; i++) {
74 twos[i]->object.flags |= PARENT2;
75 prio_queue_put(&queue, twos[i]);
78 while (queue_has_nonstale(&queue)) {
79 struct commit *commit = prio_queue_get(&queue);
80 struct commit_list *parents;
81 int flags;
82 timestamp_t generation = commit_graph_generation(commit);
84 if (min_generation && generation > last_gen)
85 BUG("bad generation skip %"PRItime" > %"PRItime" at %s",
86 generation, last_gen,
87 oid_to_hex(&commit->object.oid));
88 last_gen = generation;
90 if (generation < min_generation)
91 break;
93 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
94 if (flags == (PARENT1 | PARENT2)) {
95 if (!(commit->object.flags & RESULT)) {
96 commit->object.flags |= RESULT;
97 commit_list_insert_by_date(commit, result);
99 /* Mark parents of a found merge stale */
100 flags |= STALE;
102 parents = commit->parents;
103 while (parents) {
104 struct commit *p = parents->item;
105 parents = parents->next;
106 if ((p->object.flags & flags) == flags)
107 continue;
108 if (repo_parse_commit(r, p)) {
109 clear_prio_queue(&queue);
110 free_commit_list(*result);
111 *result = NULL;
113 * At this stage, we know that the commit is
114 * missing: `repo_parse_commit()` uses
115 * `OBJECT_INFO_DIE_IF_CORRUPT` and therefore
116 * corrupt commits would already have been
117 * dispatched with a `die()`.
119 if (ignore_missing_commits)
120 return 0;
121 return error(_("could not parse commit %s"),
122 oid_to_hex(&p->object.oid));
124 p->object.flags |= flags;
125 prio_queue_put(&queue, p);
129 clear_prio_queue(&queue);
130 return 0;
133 static int merge_bases_many(struct repository *r,
134 struct commit *one, int n,
135 struct commit **twos,
136 struct commit_list **result)
138 struct commit_list *list = NULL;
139 int i;
141 for (i = 0; i < n; i++) {
142 if (one == twos[i]) {
144 * We do not mark this even with RESULT so we do not
145 * have to clean it up.
147 *result = commit_list_insert(one, result);
148 return 0;
152 if (!one)
153 return 0;
154 if (repo_parse_commit(r, one))
155 return error(_("could not parse commit %s"),
156 oid_to_hex(&one->object.oid));
157 for (i = 0; i < n; i++) {
158 if (!twos[i])
159 return 0;
160 if (repo_parse_commit(r, twos[i]))
161 return error(_("could not parse commit %s"),
162 oid_to_hex(&twos[i]->object.oid));
165 if (paint_down_to_common(r, one, n, twos, 0, 0, &list)) {
166 free_commit_list(list);
167 return -1;
170 while (list) {
171 struct commit *commit = pop_commit(&list);
172 if (!(commit->object.flags & STALE))
173 commit_list_insert_by_date(commit, result);
175 return 0;
178 int get_octopus_merge_bases(struct commit_list *in, struct commit_list **result)
180 struct commit_list *i, *j, *k;
182 if (!in)
183 return 0;
185 commit_list_insert(in->item, result);
187 for (i = in->next; i; i = i->next) {
188 struct commit_list *new_commits = NULL, *end = NULL;
190 for (j = *result; j; j = j->next) {
191 struct commit_list *bases = NULL;
192 if (repo_get_merge_bases(the_repository, i->item,
193 j->item, &bases) < 0) {
194 free_commit_list(bases);
195 free_commit_list(*result);
196 *result = NULL;
197 return -1;
199 if (!new_commits)
200 new_commits = bases;
201 else
202 end->next = bases;
203 for (k = bases; k; k = k->next)
204 end = k;
206 free_commit_list(*result);
207 *result = new_commits;
209 return 0;
212 static int remove_redundant_no_gen(struct repository *r,
213 struct commit **array, int cnt)
215 struct commit **work;
216 unsigned char *redundant;
217 int *filled_index;
218 int i, j, filled;
220 CALLOC_ARRAY(work, cnt);
221 redundant = xcalloc(cnt, 1);
222 ALLOC_ARRAY(filled_index, cnt - 1);
224 for (i = 0; i < cnt; i++)
225 repo_parse_commit(r, array[i]);
226 for (i = 0; i < cnt; i++) {
227 struct commit_list *common = NULL;
228 timestamp_t min_generation = commit_graph_generation(array[i]);
230 if (redundant[i])
231 continue;
232 for (j = filled = 0; j < cnt; j++) {
233 timestamp_t curr_generation;
234 if (i == j || redundant[j])
235 continue;
236 filled_index[filled] = j;
237 work[filled++] = array[j];
239 curr_generation = commit_graph_generation(array[j]);
240 if (curr_generation < min_generation)
241 min_generation = curr_generation;
243 if (paint_down_to_common(r, array[i], filled,
244 work, min_generation, 0, &common)) {
245 clear_commit_marks(array[i], all_flags);
246 clear_commit_marks_many(filled, work, all_flags);
247 free_commit_list(common);
248 free(work);
249 free(redundant);
250 free(filled_index);
251 return -1;
253 if (array[i]->object.flags & PARENT2)
254 redundant[i] = 1;
255 for (j = 0; j < filled; j++)
256 if (work[j]->object.flags & PARENT1)
257 redundant[filled_index[j]] = 1;
258 clear_commit_marks(array[i], all_flags);
259 clear_commit_marks_many(filled, work, all_flags);
260 free_commit_list(common);
263 /* Now collect the result */
264 COPY_ARRAY(work, array, cnt);
265 for (i = filled = 0; i < cnt; i++)
266 if (!redundant[i])
267 array[filled++] = work[i];
268 free(work);
269 free(redundant);
270 free(filled_index);
271 return filled;
274 static int remove_redundant_with_gen(struct repository *r,
275 struct commit **array, int cnt)
277 int i, count_non_stale = 0, count_still_independent = cnt;
278 timestamp_t min_generation = GENERATION_NUMBER_INFINITY;
279 struct commit **walk_start, **sorted;
280 size_t walk_start_nr = 0, walk_start_alloc = cnt;
281 int min_gen_pos = 0;
284 * Sort the input by generation number, ascending. This allows
285 * us to increase the "min_generation" limit when we discover
286 * the commit with lowest generation is STALE. The index
287 * min_gen_pos points to the current position within 'array'
288 * that is not yet known to be STALE.
290 DUP_ARRAY(sorted, array, cnt);
291 QSORT(sorted, cnt, compare_commits_by_gen);
292 min_generation = commit_graph_generation(sorted[0]);
294 ALLOC_ARRAY(walk_start, walk_start_alloc);
296 /* Mark all parents of the input as STALE */
297 for (i = 0; i < cnt; i++) {
298 struct commit_list *parents;
300 repo_parse_commit(r, array[i]);
301 array[i]->object.flags |= RESULT;
302 parents = array[i]->parents;
304 while (parents) {
305 repo_parse_commit(r, parents->item);
306 if (!(parents->item->object.flags & STALE)) {
307 parents->item->object.flags |= STALE;
308 ALLOC_GROW(walk_start, walk_start_nr + 1, walk_start_alloc);
309 walk_start[walk_start_nr++] = parents->item;
311 parents = parents->next;
315 QSORT(walk_start, walk_start_nr, compare_commits_by_gen);
317 /* remove STALE bit for now to allow walking through parents */
318 for (i = 0; i < walk_start_nr; i++)
319 walk_start[i]->object.flags &= ~STALE;
322 * Start walking from the highest generation. Hopefully, it will
323 * find all other items during the first-parent walk, and we can
324 * terminate early. Otherwise, we will do the same amount of work
325 * as before.
327 for (i = walk_start_nr - 1; i >= 0 && count_still_independent > 1; i--) {
328 /* push the STALE bits up to min generation */
329 struct commit_list *stack = NULL;
331 commit_list_insert(walk_start[i], &stack);
332 walk_start[i]->object.flags |= STALE;
334 while (stack) {
335 struct commit_list *parents;
336 struct commit *c = stack->item;
338 repo_parse_commit(r, c);
340 if (c->object.flags & RESULT) {
341 c->object.flags &= ~RESULT;
342 if (--count_still_independent <= 1)
343 break;
344 if (oideq(&c->object.oid, &sorted[min_gen_pos]->object.oid)) {
345 while (min_gen_pos < cnt - 1 &&
346 (sorted[min_gen_pos]->object.flags & STALE))
347 min_gen_pos++;
348 min_generation = commit_graph_generation(sorted[min_gen_pos]);
352 if (commit_graph_generation(c) < min_generation) {
353 pop_commit(&stack);
354 continue;
357 parents = c->parents;
358 while (parents) {
359 if (!(parents->item->object.flags & STALE)) {
360 parents->item->object.flags |= STALE;
361 commit_list_insert(parents->item, &stack);
362 break;
364 parents = parents->next;
367 /* pop if all parents have been visited already */
368 if (!parents)
369 pop_commit(&stack);
371 free_commit_list(stack);
373 free(sorted);
375 /* clear result */
376 for (i = 0; i < cnt; i++)
377 array[i]->object.flags &= ~RESULT;
379 /* rearrange array */
380 for (i = count_non_stale = 0; i < cnt; i++) {
381 if (!(array[i]->object.flags & STALE))
382 array[count_non_stale++] = array[i];
385 /* clear marks */
386 clear_commit_marks_many(walk_start_nr, walk_start, STALE);
387 free(walk_start);
389 return count_non_stale;
392 static int remove_redundant(struct repository *r, struct commit **array, int cnt)
395 * Some commit in the array may be an ancestor of
396 * another commit. Move the independent commits to the
397 * beginning of 'array' and return their number. Callers
398 * should not rely upon the contents of 'array' after
399 * that number.
401 if (generation_numbers_enabled(r)) {
402 int i;
405 * If we have a single commit with finite generation
406 * number, then the _with_gen algorithm is preferred.
408 for (i = 0; i < cnt; i++) {
409 if (commit_graph_generation(array[i]) < GENERATION_NUMBER_INFINITY)
410 return remove_redundant_with_gen(r, array, cnt);
414 return remove_redundant_no_gen(r, array, cnt);
417 static int get_merge_bases_many_0(struct repository *r,
418 struct commit *one,
419 int n,
420 struct commit **twos,
421 int cleanup,
422 struct commit_list **result)
424 struct commit_list *list;
425 struct commit **rslt;
426 int cnt, i;
428 if (merge_bases_many(r, one, n, twos, result) < 0)
429 return -1;
430 for (i = 0; i < n; i++) {
431 if (one == twos[i])
432 return 0;
434 if (!*result || !(*result)->next) {
435 if (cleanup) {
436 clear_commit_marks(one, all_flags);
437 clear_commit_marks_many(n, twos, all_flags);
439 return 0;
442 /* There are more than one */
443 cnt = commit_list_count(*result);
444 CALLOC_ARRAY(rslt, cnt);
445 for (list = *result, i = 0; list; list = list->next)
446 rslt[i++] = list->item;
447 free_commit_list(*result);
448 *result = NULL;
450 clear_commit_marks(one, all_flags);
451 clear_commit_marks_many(n, twos, all_flags);
453 cnt = remove_redundant(r, rslt, cnt);
454 if (cnt < 0) {
455 free(rslt);
456 return -1;
458 for (i = 0; i < cnt; i++)
459 commit_list_insert_by_date(rslt[i], result);
460 free(rslt);
461 return 0;
464 int repo_get_merge_bases_many(struct repository *r,
465 struct commit *one,
466 int n,
467 struct commit **twos,
468 struct commit_list **result)
470 return get_merge_bases_many_0(r, one, n, twos, 1, result);
473 int repo_get_merge_bases_many_dirty(struct repository *r,
474 struct commit *one,
475 int n,
476 struct commit **twos,
477 struct commit_list **result)
479 return get_merge_bases_many_0(r, one, n, twos, 0, result);
482 int repo_get_merge_bases(struct repository *r,
483 struct commit *one,
484 struct commit *two,
485 struct commit_list **result)
487 return get_merge_bases_many_0(r, one, 1, &two, 1, result);
491 * Is "commit" a descendant of one of the elements on the "with_commit" list?
493 int repo_is_descendant_of(struct repository *r,
494 struct commit *commit,
495 struct commit_list *with_commit)
497 if (!with_commit)
498 return 1;
500 if (generation_numbers_enabled(r)) {
501 struct commit_list *from_list = NULL;
502 int result;
503 commit_list_insert(commit, &from_list);
504 result = can_all_from_reach(from_list, with_commit, 0);
505 free_commit_list(from_list);
506 return result;
507 } else {
508 while (with_commit) {
509 struct commit *other;
510 int ret;
512 other = with_commit->item;
513 with_commit = with_commit->next;
514 ret = repo_in_merge_bases_many(r, other, 1, &commit, 0);
515 if (ret)
516 return ret;
518 return 0;
523 * Is "commit" an ancestor of one of the "references"?
525 int repo_in_merge_bases_many(struct repository *r, struct commit *commit,
526 int nr_reference, struct commit **reference,
527 int ignore_missing_commits)
529 struct commit_list *bases = NULL;
530 int ret = 0, i;
531 timestamp_t generation, max_generation = GENERATION_NUMBER_ZERO;
533 if (repo_parse_commit(r, commit))
534 return ignore_missing_commits ? 0 : -1;
535 for (i = 0; i < nr_reference; i++) {
536 if (repo_parse_commit(r, reference[i]))
537 return ignore_missing_commits ? 0 : -1;
539 generation = commit_graph_generation(reference[i]);
540 if (generation > max_generation)
541 max_generation = generation;
544 generation = commit_graph_generation(commit);
545 if (generation > max_generation)
546 return ret;
548 if (paint_down_to_common(r, commit,
549 nr_reference, reference,
550 generation, ignore_missing_commits, &bases))
551 ret = -1;
552 else if (commit->object.flags & PARENT2)
553 ret = 1;
554 clear_commit_marks(commit, all_flags);
555 clear_commit_marks_many(nr_reference, reference, all_flags);
556 free_commit_list(bases);
557 return ret;
561 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
563 int repo_in_merge_bases(struct repository *r,
564 struct commit *commit,
565 struct commit *reference)
567 int res;
568 struct commit_list *list = NULL;
569 struct commit_list **next = &list;
571 next = commit_list_append(commit, next);
572 res = repo_is_descendant_of(r, reference, list);
573 free_commit_list(list);
575 return res;
578 struct commit_list *reduce_heads(struct commit_list *heads)
580 struct commit_list *p;
581 struct commit_list *result = NULL, **tail = &result;
582 struct commit **array;
583 int num_head, i;
585 if (!heads)
586 return NULL;
588 /* Uniquify */
589 for (p = heads; p; p = p->next)
590 p->item->object.flags &= ~STALE;
591 for (p = heads, num_head = 0; p; p = p->next) {
592 if (p->item->object.flags & STALE)
593 continue;
594 p->item->object.flags |= STALE;
595 num_head++;
597 CALLOC_ARRAY(array, num_head);
598 for (p = heads, i = 0; p; p = p->next) {
599 if (p->item->object.flags & STALE) {
600 array[i++] = p->item;
601 p->item->object.flags &= ~STALE;
604 num_head = remove_redundant(the_repository, array, num_head);
605 if (num_head < 0) {
606 free(array);
607 return NULL;
609 for (i = 0; i < num_head; i++)
610 tail = &commit_list_insert(array[i], tail)->next;
611 free(array);
612 return result;
615 void reduce_heads_replace(struct commit_list **heads)
617 struct commit_list *result = reduce_heads(*heads);
618 free_commit_list(*heads);
619 *heads = result;
622 int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
624 struct object *o;
625 struct commit *old_commit, *new_commit;
626 struct commit_list *old_commit_list = NULL;
627 int ret;
630 * Both new_commit and old_commit must be commit-ish and new_commit is descendant of
631 * old_commit. Otherwise we require --force.
633 o = deref_tag(the_repository, parse_object(the_repository, old_oid),
634 NULL, 0);
635 if (!o || o->type != OBJ_COMMIT)
636 return 0;
637 old_commit = (struct commit *) o;
639 o = deref_tag(the_repository, parse_object(the_repository, new_oid),
640 NULL, 0);
641 if (!o || o->type != OBJ_COMMIT)
642 return 0;
643 new_commit = (struct commit *) o;
645 if (repo_parse_commit(the_repository, new_commit) < 0)
646 return 0;
648 commit_list_insert(old_commit, &old_commit_list);
649 ret = repo_is_descendant_of(the_repository,
650 new_commit, old_commit_list);
651 if (ret < 0)
652 exit(128);
653 free_commit_list(old_commit_list);
654 return ret;
658 * Mimicking the real stack, this stack lives on the heap, avoiding stack
659 * overflows.
661 * At each recursion step, the stack items points to the commits whose
662 * ancestors are to be inspected.
664 struct contains_stack {
665 int nr, alloc;
666 struct contains_stack_entry {
667 struct commit *commit;
668 struct commit_list *parents;
669 } *contains_stack;
672 static int in_commit_list(const struct commit_list *want, struct commit *c)
674 for (; want; want = want->next)
675 if (oideq(&want->item->object.oid, &c->object.oid))
676 return 1;
677 return 0;
681 * Test whether the candidate is contained in the list.
682 * Do not recurse to find out, though, but return -1 if inconclusive.
684 static enum contains_result contains_test(struct commit *candidate,
685 const struct commit_list *want,
686 struct contains_cache *cache,
687 timestamp_t cutoff)
689 enum contains_result *cached = contains_cache_at(cache, candidate);
691 /* If we already have the answer cached, return that. */
692 if (*cached)
693 return *cached;
695 /* or are we it? */
696 if (in_commit_list(want, candidate)) {
697 *cached = CONTAINS_YES;
698 return CONTAINS_YES;
701 /* Otherwise, we don't know; prepare to recurse */
702 parse_commit_or_die(candidate);
704 if (commit_graph_generation(candidate) < cutoff)
705 return CONTAINS_NO;
707 return CONTAINS_UNKNOWN;
710 static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
712 ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
713 contains_stack->contains_stack[contains_stack->nr].commit = candidate;
714 contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
717 static enum contains_result contains_tag_algo(struct commit *candidate,
718 const struct commit_list *want,
719 struct contains_cache *cache)
721 struct contains_stack contains_stack = { 0, 0, NULL };
722 enum contains_result result;
723 timestamp_t cutoff = GENERATION_NUMBER_INFINITY;
724 const struct commit_list *p;
726 for (p = want; p; p = p->next) {
727 timestamp_t generation;
728 struct commit *c = p->item;
729 load_commit_graph_info(the_repository, c);
730 generation = commit_graph_generation(c);
731 if (generation < cutoff)
732 cutoff = generation;
735 result = contains_test(candidate, want, cache, cutoff);
736 if (result != CONTAINS_UNKNOWN)
737 return result;
739 push_to_contains_stack(candidate, &contains_stack);
740 while (contains_stack.nr) {
741 struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
742 struct commit *commit = entry->commit;
743 struct commit_list *parents = entry->parents;
745 if (!parents) {
746 *contains_cache_at(cache, commit) = CONTAINS_NO;
747 contains_stack.nr--;
750 * If we just popped the stack, parents->item has been marked,
751 * therefore contains_test will return a meaningful yes/no.
753 else switch (contains_test(parents->item, want, cache, cutoff)) {
754 case CONTAINS_YES:
755 *contains_cache_at(cache, commit) = CONTAINS_YES;
756 contains_stack.nr--;
757 break;
758 case CONTAINS_NO:
759 entry->parents = parents->next;
760 break;
761 case CONTAINS_UNKNOWN:
762 push_to_contains_stack(parents->item, &contains_stack);
763 break;
766 free(contains_stack.contains_stack);
767 return contains_test(candidate, want, cache, cutoff);
770 int commit_contains(struct ref_filter *filter, struct commit *commit,
771 struct commit_list *list, struct contains_cache *cache)
773 if (filter->with_commit_tag_algo)
774 return contains_tag_algo(commit, list, cache) == CONTAINS_YES;
775 return repo_is_descendant_of(the_repository, commit, list);
778 int can_all_from_reach_with_flag(struct object_array *from,
779 unsigned int with_flag,
780 unsigned int assign_flag,
781 time_t min_commit_date,
782 timestamp_t min_generation)
784 struct commit **list = NULL;
785 int i;
786 int nr_commits;
787 int result = 1;
789 ALLOC_ARRAY(list, from->nr);
790 nr_commits = 0;
791 for (i = 0; i < from->nr; i++) {
792 struct object *from_one = from->objects[i].item;
794 if (!from_one || from_one->flags & assign_flag)
795 continue;
797 from_one = deref_tag(the_repository, from_one,
798 "a from object", 0);
799 if (!from_one || from_one->type != OBJ_COMMIT) {
801 * no way to tell if this is reachable by
802 * looking at the ancestry chain alone, so
803 * leave a note to ourselves not to worry about
804 * this object anymore.
806 from->objects[i].item->flags |= assign_flag;
807 continue;
810 list[nr_commits] = (struct commit *)from_one;
811 if (repo_parse_commit(the_repository, list[nr_commits]) ||
812 commit_graph_generation(list[nr_commits]) < min_generation) {
813 result = 0;
814 goto cleanup;
817 nr_commits++;
820 QSORT(list, nr_commits, compare_commits_by_gen);
822 for (i = 0; i < nr_commits; i++) {
823 /* DFS from list[i] */
824 struct commit_list *stack = NULL;
826 list[i]->object.flags |= assign_flag;
827 commit_list_insert(list[i], &stack);
829 while (stack) {
830 struct commit_list *parent;
832 if (stack->item->object.flags & (with_flag | RESULT)) {
833 pop_commit(&stack);
834 if (stack)
835 stack->item->object.flags |= RESULT;
836 continue;
839 for (parent = stack->item->parents; parent; parent = parent->next) {
840 if (parent->item->object.flags & (with_flag | RESULT))
841 stack->item->object.flags |= RESULT;
843 if (!(parent->item->object.flags & assign_flag)) {
844 parent->item->object.flags |= assign_flag;
846 if (repo_parse_commit(the_repository, parent->item) ||
847 parent->item->date < min_commit_date ||
848 commit_graph_generation(parent->item) < min_generation)
849 continue;
851 commit_list_insert(parent->item, &stack);
852 break;
856 if (!parent)
857 pop_commit(&stack);
860 if (!(list[i]->object.flags & (with_flag | RESULT))) {
861 result = 0;
862 goto cleanup;
866 cleanup:
867 clear_commit_marks_many(nr_commits, list, RESULT | assign_flag);
868 free(list);
870 for (i = 0; i < from->nr; i++) {
871 struct object *from_one = from->objects[i].item;
873 if (from_one)
874 from_one->flags &= ~assign_flag;
877 return result;
880 int can_all_from_reach(struct commit_list *from, struct commit_list *to,
881 int cutoff_by_min_date)
883 struct object_array from_objs = OBJECT_ARRAY_INIT;
884 time_t min_commit_date = cutoff_by_min_date ? from->item->date : 0;
885 struct commit_list *from_iter = from, *to_iter = to;
886 int result;
887 timestamp_t min_generation = GENERATION_NUMBER_INFINITY;
889 while (from_iter) {
890 add_object_array(&from_iter->item->object, NULL, &from_objs);
892 if (!repo_parse_commit(the_repository, from_iter->item)) {
893 timestamp_t generation;
894 if (from_iter->item->date < min_commit_date)
895 min_commit_date = from_iter->item->date;
897 generation = commit_graph_generation(from_iter->item);
898 if (generation < min_generation)
899 min_generation = generation;
902 from_iter = from_iter->next;
905 while (to_iter) {
906 if (!repo_parse_commit(the_repository, to_iter->item)) {
907 timestamp_t generation;
908 if (to_iter->item->date < min_commit_date)
909 min_commit_date = to_iter->item->date;
911 generation = commit_graph_generation(to_iter->item);
912 if (generation < min_generation)
913 min_generation = generation;
916 to_iter->item->object.flags |= PARENT2;
918 to_iter = to_iter->next;
921 result = can_all_from_reach_with_flag(&from_objs, PARENT2, PARENT1,
922 min_commit_date, min_generation);
924 while (from) {
925 clear_commit_marks(from->item, PARENT1);
926 from = from->next;
929 while (to) {
930 clear_commit_marks(to->item, PARENT2);
931 to = to->next;
934 object_array_clear(&from_objs);
935 return result;
938 struct commit_list *get_reachable_subset(struct commit **from, int nr_from,
939 struct commit **to, int nr_to,
940 unsigned int reachable_flag)
942 struct commit **item;
943 struct commit *current;
944 struct commit_list *found_commits = NULL;
945 struct commit **to_last = to + nr_to;
946 struct commit **from_last = from + nr_from;
947 timestamp_t min_generation = GENERATION_NUMBER_INFINITY;
948 int num_to_find = 0;
950 struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
952 for (item = to; item < to_last; item++) {
953 timestamp_t generation;
954 struct commit *c = *item;
956 repo_parse_commit(the_repository, c);
957 generation = commit_graph_generation(c);
958 if (generation < min_generation)
959 min_generation = generation;
961 if (!(c->object.flags & PARENT1)) {
962 c->object.flags |= PARENT1;
963 num_to_find++;
967 for (item = from; item < from_last; item++) {
968 struct commit *c = *item;
969 if (!(c->object.flags & PARENT2)) {
970 c->object.flags |= PARENT2;
971 repo_parse_commit(the_repository, c);
973 prio_queue_put(&queue, *item);
977 while (num_to_find && (current = prio_queue_get(&queue)) != NULL) {
978 struct commit_list *parents;
980 if (current->object.flags & PARENT1) {
981 current->object.flags &= ~PARENT1;
982 current->object.flags |= reachable_flag;
983 commit_list_insert(current, &found_commits);
984 num_to_find--;
987 for (parents = current->parents; parents; parents = parents->next) {
988 struct commit *p = parents->item;
990 repo_parse_commit(the_repository, p);
992 if (commit_graph_generation(p) < min_generation)
993 continue;
995 if (p->object.flags & PARENT2)
996 continue;
998 p->object.flags |= PARENT2;
999 prio_queue_put(&queue, p);
1003 clear_prio_queue(&queue);
1005 clear_commit_marks_many(nr_to, to, PARENT1);
1006 clear_commit_marks_many(nr_from, from, PARENT2);
1008 return found_commits;
1011 define_commit_slab(bit_arrays, struct bitmap *);
1012 static struct bit_arrays bit_arrays;
1014 static void insert_no_dup(struct prio_queue *queue, struct commit *c)
1016 if (c->object.flags & PARENT2)
1017 return;
1018 prio_queue_put(queue, c);
1019 c->object.flags |= PARENT2;
1022 static struct bitmap *get_bit_array(struct commit *c, int width)
1024 struct bitmap **bitmap = bit_arrays_at(&bit_arrays, c);
1025 if (!*bitmap)
1026 *bitmap = bitmap_word_alloc(width);
1027 return *bitmap;
1030 static void free_bit_array(struct commit *c)
1032 struct bitmap **bitmap = bit_arrays_at(&bit_arrays, c);
1033 if (!*bitmap)
1034 return;
1035 bitmap_free(*bitmap);
1036 *bitmap = NULL;
1039 void ahead_behind(struct repository *r,
1040 struct commit **commits, size_t commits_nr,
1041 struct ahead_behind_count *counts, size_t counts_nr)
1043 struct prio_queue queue = { .compare = compare_commits_by_gen_then_commit_date };
1044 size_t width = DIV_ROUND_UP(commits_nr, BITS_IN_EWORD);
1046 if (!commits_nr || !counts_nr)
1047 return;
1049 for (size_t i = 0; i < counts_nr; i++) {
1050 counts[i].ahead = 0;
1051 counts[i].behind = 0;
1054 ensure_generations_valid(r, commits, commits_nr);
1056 init_bit_arrays(&bit_arrays);
1058 for (size_t i = 0; i < commits_nr; i++) {
1059 struct commit *c = commits[i];
1060 struct bitmap *bitmap = get_bit_array(c, width);
1062 bitmap_set(bitmap, i);
1063 insert_no_dup(&queue, c);
1066 while (queue_has_nonstale(&queue)) {
1067 struct commit *c = prio_queue_get(&queue);
1068 struct commit_list *p;
1069 struct bitmap *bitmap_c = get_bit_array(c, width);
1071 for (size_t i = 0; i < counts_nr; i++) {
1072 int reach_from_tip = !!bitmap_get(bitmap_c, counts[i].tip_index);
1073 int reach_from_base = !!bitmap_get(bitmap_c, counts[i].base_index);
1075 if (reach_from_tip ^ reach_from_base) {
1076 if (reach_from_base)
1077 counts[i].behind++;
1078 else
1079 counts[i].ahead++;
1083 for (p = c->parents; p; p = p->next) {
1084 struct bitmap *bitmap_p;
1086 repo_parse_commit(r, p->item);
1088 bitmap_p = get_bit_array(p->item, width);
1089 bitmap_or(bitmap_p, bitmap_c);
1092 * If this parent is reachable from every starting
1093 * commit, then none of its ancestors can contribute
1094 * to the ahead/behind count. Mark it as STALE, so
1095 * we can stop the walk when every commit in the
1096 * queue is STALE.
1098 if (bitmap_popcount(bitmap_p) == commits_nr)
1099 p->item->object.flags |= STALE;
1101 insert_no_dup(&queue, p->item);
1104 free_bit_array(c);
1107 /* STALE is used here, PARENT2 is used by insert_no_dup(). */
1108 repo_clear_commit_marks(r, PARENT2 | STALE);
1109 clear_bit_arrays(&bit_arrays);
1110 clear_prio_queue(&queue);
1113 struct commit_and_index {
1114 struct commit *commit;
1115 unsigned int index;
1116 timestamp_t generation;
1119 static int compare_commit_and_index_by_generation(const void *va, const void *vb)
1121 const struct commit_and_index *a = (const struct commit_and_index *)va;
1122 const struct commit_and_index *b = (const struct commit_and_index *)vb;
1124 if (a->generation > b->generation)
1125 return 1;
1126 if (a->generation < b->generation)
1127 return -1;
1128 return 0;
1131 void tips_reachable_from_bases(struct repository *r,
1132 struct commit_list *bases,
1133 struct commit **tips, size_t tips_nr,
1134 int mark)
1136 struct commit_and_index *commits;
1137 size_t min_generation_index = 0;
1138 timestamp_t min_generation;
1139 struct commit_list *stack = NULL;
1141 if (!bases || !tips || !tips_nr)
1142 return;
1145 * Do a depth-first search starting at 'bases' to search for the
1146 * tips. Stop at the lowest (un-found) generation number. When
1147 * finding the lowest commit, increase the minimum generation
1148 * number to the next lowest (un-found) generation number.
1151 CALLOC_ARRAY(commits, tips_nr);
1153 for (size_t i = 0; i < tips_nr; i++) {
1154 commits[i].commit = tips[i];
1155 commits[i].index = i;
1156 commits[i].generation = commit_graph_generation(tips[i]);
1159 /* Sort with generation number ascending. */
1160 QSORT(commits, tips_nr, compare_commit_and_index_by_generation);
1161 min_generation = commits[0].generation;
1163 while (bases) {
1164 repo_parse_commit(r, bases->item);
1165 commit_list_insert(bases->item, &stack);
1166 bases = bases->next;
1169 while (stack) {
1170 int explored_all_parents = 1;
1171 struct commit_list *p;
1172 struct commit *c = stack->item;
1173 timestamp_t c_gen = commit_graph_generation(c);
1175 /* Does it match any of our tips? */
1176 for (size_t j = min_generation_index; j < tips_nr; j++) {
1177 if (c_gen < commits[j].generation)
1178 break;
1180 if (commits[j].commit == c) {
1181 tips[commits[j].index]->object.flags |= mark;
1183 if (j == min_generation_index) {
1184 unsigned int k = j + 1;
1185 while (k < tips_nr &&
1186 (tips[commits[k].index]->object.flags & mark))
1187 k++;
1189 /* Terminate early if all found. */
1190 if (k >= tips_nr)
1191 goto done;
1193 min_generation_index = k;
1194 min_generation = commits[k].generation;
1199 for (p = c->parents; p; p = p->next) {
1200 repo_parse_commit(r, p->item);
1202 /* Have we already explored this parent? */
1203 if (p->item->object.flags & SEEN)
1204 continue;
1206 /* Is it below the current minimum generation? */
1207 if (commit_graph_generation(p->item) < min_generation)
1208 continue;
1210 /* Ok, we will explore from here on. */
1211 p->item->object.flags |= SEEN;
1212 explored_all_parents = 0;
1213 commit_list_insert(p->item, &stack);
1214 break;
1217 if (explored_all_parents)
1218 pop_commit(&stack);
1221 done:
1222 free(commits);
1223 repo_clear_commit_marks(r, SEEN);