Merge branch 'jt/http-redact-cookies' into maint
[git.git] / shallow.c
blobdf4d44ea7a34a6d6bef119d1494f1c055614cbb1
1 #include "cache.h"
2 #include "tempfile.h"
3 #include "lockfile.h"
4 #include "commit.h"
5 #include "tag.h"
6 #include "pkt-line.h"
7 #include "remote.h"
8 #include "refs.h"
9 #include "sha1-array.h"
10 #include "diff.h"
11 #include "revision.h"
12 #include "commit-slab.h"
13 #include "revision.h"
14 #include "list-objects.h"
16 static int is_shallow = -1;
17 static struct stat_validity shallow_stat;
18 static char *alternate_shallow_file;
20 void set_alternate_shallow_file(const char *path, int override)
22 if (is_shallow != -1)
23 die("BUG: is_repository_shallow must not be called before set_alternate_shallow_file");
24 if (alternate_shallow_file && !override)
25 return;
26 free(alternate_shallow_file);
27 alternate_shallow_file = xstrdup_or_null(path);
30 int register_shallow(const struct object_id *oid)
32 struct commit_graft *graft =
33 xmalloc(sizeof(struct commit_graft));
34 struct commit *commit = lookup_commit(oid);
36 oidcpy(&graft->oid, oid);
37 graft->nr_parent = -1;
38 if (commit && commit->object.parsed)
39 commit->parents = NULL;
40 return register_commit_graft(graft, 0);
43 int is_repository_shallow(void)
45 FILE *fp;
46 char buf[1024];
47 const char *path = alternate_shallow_file;
49 if (is_shallow >= 0)
50 return is_shallow;
52 if (!path)
53 path = git_path_shallow();
55 * fetch-pack sets '--shallow-file ""' as an indicator that no
56 * shallow file should be used. We could just open it and it
57 * will likely fail. But let's do an explicit check instead.
59 if (!*path || (fp = fopen(path, "r")) == NULL) {
60 stat_validity_clear(&shallow_stat);
61 is_shallow = 0;
62 return is_shallow;
64 stat_validity_update(&shallow_stat, fileno(fp));
65 is_shallow = 1;
67 while (fgets(buf, sizeof(buf), fp)) {
68 struct object_id oid;
69 if (get_oid_hex(buf, &oid))
70 die("bad shallow line: %s", buf);
71 register_shallow(&oid);
73 fclose(fp);
74 return is_shallow;
77 struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
78 int shallow_flag, int not_shallow_flag)
80 int i = 0, cur_depth = 0;
81 struct commit_list *result = NULL;
82 struct object_array stack = OBJECT_ARRAY_INIT;
83 struct commit *commit = NULL;
84 struct commit_graft *graft;
86 while (commit || i < heads->nr || stack.nr) {
87 struct commit_list *p;
88 if (!commit) {
89 if (i < heads->nr) {
90 commit = (struct commit *)
91 deref_tag(heads->objects[i++].item, NULL, 0);
92 if (!commit || commit->object.type != OBJ_COMMIT) {
93 commit = NULL;
94 continue;
96 if (!commit->util)
97 commit->util = xmalloc(sizeof(int));
98 *(int *)commit->util = 0;
99 cur_depth = 0;
100 } else {
101 commit = (struct commit *)
102 object_array_pop(&stack);
103 cur_depth = *(int *)commit->util;
106 parse_commit_or_die(commit);
107 cur_depth++;
108 if ((depth != INFINITE_DEPTH && cur_depth >= depth) ||
109 (is_repository_shallow() && !commit->parents &&
110 (graft = lookup_commit_graft(&commit->object.oid)) != NULL &&
111 graft->nr_parent < 0)) {
112 commit_list_insert(commit, &result);
113 commit->object.flags |= shallow_flag;
114 commit = NULL;
115 continue;
117 commit->object.flags |= not_shallow_flag;
118 for (p = commit->parents, commit = NULL; p; p = p->next) {
119 if (!p->item->util) {
120 int *pointer = xmalloc(sizeof(int));
121 p->item->util = pointer;
122 *pointer = cur_depth;
123 } else {
124 int *pointer = p->item->util;
125 if (cur_depth >= *pointer)
126 continue;
127 *pointer = cur_depth;
129 if (p->next)
130 add_object_array(&p->item->object,
131 NULL, &stack);
132 else {
133 commit = p->item;
134 cur_depth = *(int *)commit->util;
139 return result;
142 static void show_commit(struct commit *commit, void *data)
144 commit_list_insert(commit, data);
148 * Given rev-list arguments, run rev-list. All reachable commits
149 * except border ones are marked with not_shallow_flag. Border commits
150 * are marked with shallow_flag. The list of border/shallow commits
151 * are also returned.
153 struct commit_list *get_shallow_commits_by_rev_list(int ac, const char **av,
154 int shallow_flag,
155 int not_shallow_flag)
157 struct commit_list *result = NULL, *p;
158 struct commit_list *not_shallow_list = NULL;
159 struct rev_info revs;
160 int both_flags = shallow_flag | not_shallow_flag;
163 * SHALLOW (excluded) and NOT_SHALLOW (included) should not be
164 * set at this point. But better be safe than sorry.
166 clear_object_flags(both_flags);
168 is_repository_shallow(); /* make sure shallows are read */
170 init_revisions(&revs, NULL);
171 save_commit_buffer = 0;
172 setup_revisions(ac, av, &revs, NULL);
174 if (prepare_revision_walk(&revs))
175 die("revision walk setup failed");
176 traverse_commit_list(&revs, show_commit, NULL, &not_shallow_list);
178 /* Mark all reachable commits as NOT_SHALLOW */
179 for (p = not_shallow_list; p; p = p->next)
180 p->item->object.flags |= not_shallow_flag;
183 * mark border commits SHALLOW + NOT_SHALLOW.
184 * We cannot clear NOT_SHALLOW right now. Imagine border
185 * commit A is processed first, then commit B, whose parent is
186 * A, later. If NOT_SHALLOW on A is cleared at step 1, B
187 * itself is considered border at step 2, which is incorrect.
189 for (p = not_shallow_list; p; p = p->next) {
190 struct commit *c = p->item;
191 struct commit_list *parent;
193 if (parse_commit(c))
194 die("unable to parse commit %s",
195 oid_to_hex(&c->object.oid));
197 for (parent = c->parents; parent; parent = parent->next)
198 if (!(parent->item->object.flags & not_shallow_flag)) {
199 c->object.flags |= shallow_flag;
200 commit_list_insert(c, &result);
201 break;
204 free_commit_list(not_shallow_list);
207 * Now we can clean up NOT_SHALLOW on border commits. Having
208 * both flags set can confuse the caller.
210 for (p = result; p; p = p->next) {
211 struct object *o = &p->item->object;
212 if ((o->flags & both_flags) == both_flags)
213 o->flags &= ~not_shallow_flag;
215 return result;
218 static void check_shallow_file_for_update(void)
220 if (is_shallow == -1)
221 die("BUG: shallow must be initialized by now");
223 if (!stat_validity_check(&shallow_stat, git_path_shallow()))
224 die("shallow file has changed since we read it");
227 #define SEEN_ONLY 1
228 #define VERBOSE 2
230 struct write_shallow_data {
231 struct strbuf *out;
232 int use_pack_protocol;
233 int count;
234 unsigned flags;
237 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
239 struct write_shallow_data *data = cb_data;
240 const char *hex = oid_to_hex(&graft->oid);
241 if (graft->nr_parent != -1)
242 return 0;
243 if (data->flags & SEEN_ONLY) {
244 struct commit *c = lookup_commit(&graft->oid);
245 if (!c || !(c->object.flags & SEEN)) {
246 if (data->flags & VERBOSE)
247 printf("Removing %s from .git/shallow\n",
248 oid_to_hex(&c->object.oid));
249 return 0;
252 data->count++;
253 if (data->use_pack_protocol)
254 packet_buf_write(data->out, "shallow %s", hex);
255 else {
256 strbuf_addstr(data->out, hex);
257 strbuf_addch(data->out, '\n');
259 return 0;
262 static int write_shallow_commits_1(struct strbuf *out, int use_pack_protocol,
263 const struct oid_array *extra,
264 unsigned flags)
266 struct write_shallow_data data;
267 int i;
268 data.out = out;
269 data.use_pack_protocol = use_pack_protocol;
270 data.count = 0;
271 data.flags = flags;
272 for_each_commit_graft(write_one_shallow, &data);
273 if (!extra)
274 return data.count;
275 for (i = 0; i < extra->nr; i++) {
276 strbuf_addstr(out, oid_to_hex(extra->oid + i));
277 strbuf_addch(out, '\n');
278 data.count++;
280 return data.count;
283 int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
284 const struct oid_array *extra)
286 return write_shallow_commits_1(out, use_pack_protocol, extra, 0);
289 const char *setup_temporary_shallow(const struct oid_array *extra)
291 struct tempfile *temp;
292 struct strbuf sb = STRBUF_INIT;
294 if (write_shallow_commits(&sb, 0, extra)) {
295 temp = xmks_tempfile(git_path("shallow_XXXXXX"));
297 if (write_in_full(temp->fd, sb.buf, sb.len) < 0 ||
298 close_tempfile_gently(temp) < 0)
299 die_errno("failed to write to %s",
300 get_tempfile_path(temp));
301 strbuf_release(&sb);
302 return get_tempfile_path(temp);
305 * is_repository_shallow() sees empty string as "no shallow
306 * file".
308 return "";
311 void setup_alternate_shallow(struct lock_file *shallow_lock,
312 const char **alternate_shallow_file,
313 const struct oid_array *extra)
315 struct strbuf sb = STRBUF_INIT;
316 int fd;
318 fd = hold_lock_file_for_update(shallow_lock, git_path_shallow(),
319 LOCK_DIE_ON_ERROR);
320 check_shallow_file_for_update();
321 if (write_shallow_commits(&sb, 0, extra)) {
322 if (write_in_full(fd, sb.buf, sb.len) < 0)
323 die_errno("failed to write to %s",
324 get_lock_file_path(shallow_lock));
325 *alternate_shallow_file = get_lock_file_path(shallow_lock);
326 } else
328 * is_repository_shallow() sees empty string as "no
329 * shallow file".
331 *alternate_shallow_file = "";
332 strbuf_release(&sb);
335 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
337 int fd = *(int *)cb;
338 if (graft->nr_parent == -1)
339 packet_write_fmt(fd, "shallow %s\n", oid_to_hex(&graft->oid));
340 return 0;
343 void advertise_shallow_grafts(int fd)
345 if (!is_repository_shallow())
346 return;
347 for_each_commit_graft(advertise_shallow_grafts_cb, &fd);
351 * mark_reachable_objects() should have been run prior to this and all
352 * reachable commits marked as "SEEN".
354 void prune_shallow(int show_only)
356 static struct lock_file shallow_lock;
357 struct strbuf sb = STRBUF_INIT;
358 int fd;
360 if (show_only) {
361 write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY | VERBOSE);
362 strbuf_release(&sb);
363 return;
365 fd = hold_lock_file_for_update(&shallow_lock, git_path_shallow(),
366 LOCK_DIE_ON_ERROR);
367 check_shallow_file_for_update();
368 if (write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY)) {
369 if (write_in_full(fd, sb.buf, sb.len) < 0)
370 die_errno("failed to write to %s",
371 get_lock_file_path(&shallow_lock));
372 commit_lock_file(&shallow_lock);
373 } else {
374 unlink(git_path_shallow());
375 rollback_lock_file(&shallow_lock);
377 strbuf_release(&sb);
380 struct trace_key trace_shallow = TRACE_KEY_INIT(SHALLOW);
383 * Step 1, split sender shallow commits into "ours" and "theirs"
384 * Step 2, clean "ours" based on .git/shallow
386 void prepare_shallow_info(struct shallow_info *info, struct oid_array *sa)
388 int i;
389 trace_printf_key(&trace_shallow, "shallow: prepare_shallow_info\n");
390 memset(info, 0, sizeof(*info));
391 info->shallow = sa;
392 if (!sa)
393 return;
394 ALLOC_ARRAY(info->ours, sa->nr);
395 ALLOC_ARRAY(info->theirs, sa->nr);
396 for (i = 0; i < sa->nr; i++) {
397 if (has_object_file(sa->oid + i)) {
398 struct commit_graft *graft;
399 graft = lookup_commit_graft(&sa->oid[i]);
400 if (graft && graft->nr_parent < 0)
401 continue;
402 info->ours[info->nr_ours++] = i;
403 } else
404 info->theirs[info->nr_theirs++] = i;
408 void clear_shallow_info(struct shallow_info *info)
410 free(info->ours);
411 free(info->theirs);
414 /* Step 4, remove non-existent ones in "theirs" after getting the pack */
416 void remove_nonexistent_theirs_shallow(struct shallow_info *info)
418 struct object_id *oid = info->shallow->oid;
419 int i, dst;
420 trace_printf_key(&trace_shallow, "shallow: remove_nonexistent_theirs_shallow\n");
421 for (i = dst = 0; i < info->nr_theirs; i++) {
422 if (i != dst)
423 info->theirs[dst] = info->theirs[i];
424 if (has_object_file(oid + info->theirs[i]))
425 dst++;
427 info->nr_theirs = dst;
430 define_commit_slab(ref_bitmap, uint32_t *);
432 #define POOL_SIZE (512 * 1024)
434 struct paint_info {
435 struct ref_bitmap ref_bitmap;
436 unsigned nr_bits;
437 char **pools;
438 char *free, *end;
439 unsigned pool_count;
442 static uint32_t *paint_alloc(struct paint_info *info)
444 unsigned nr = DIV_ROUND_UP(info->nr_bits, 32);
445 unsigned size = nr * sizeof(uint32_t);
446 void *p;
447 if (!info->pool_count || size > info->end - info->free) {
448 if (size > POOL_SIZE)
449 die("BUG: pool size too small for %d in paint_alloc()",
450 size);
451 info->pool_count++;
452 REALLOC_ARRAY(info->pools, info->pool_count);
453 info->free = xmalloc(POOL_SIZE);
454 info->pools[info->pool_count - 1] = info->free;
455 info->end = info->free + POOL_SIZE;
457 p = info->free;
458 info->free += size;
459 return p;
463 * Given a commit SHA-1, walk down to parents until either SEEN,
464 * UNINTERESTING or BOTTOM is hit. Set the id-th bit in ref_bitmap for
465 * all walked commits.
467 static void paint_down(struct paint_info *info, const struct object_id *oid,
468 unsigned int id)
470 unsigned int i, nr;
471 struct commit_list *head = NULL;
472 int bitmap_nr = DIV_ROUND_UP(info->nr_bits, 32);
473 size_t bitmap_size = st_mult(sizeof(uint32_t), bitmap_nr);
474 struct commit *c = lookup_commit_reference_gently(oid, 1);
475 uint32_t *tmp; /* to be freed before return */
476 uint32_t *bitmap;
478 if (!c)
479 return;
481 tmp = xmalloc(bitmap_size);
482 bitmap = paint_alloc(info);
483 memset(bitmap, 0, bitmap_size);
484 bitmap[id / 32] |= (1U << (id % 32));
485 commit_list_insert(c, &head);
486 while (head) {
487 struct commit_list *p;
488 struct commit *c = pop_commit(&head);
489 uint32_t **refs = ref_bitmap_at(&info->ref_bitmap, c);
491 /* XXX check "UNINTERESTING" from pack bitmaps if available */
492 if (c->object.flags & (SEEN | UNINTERESTING))
493 continue;
494 else
495 c->object.flags |= SEEN;
497 if (*refs == NULL)
498 *refs = bitmap;
499 else {
500 memcpy(tmp, *refs, bitmap_size);
501 for (i = 0; i < bitmap_nr; i++)
502 tmp[i] |= bitmap[i];
503 if (memcmp(tmp, *refs, bitmap_size)) {
504 *refs = paint_alloc(info);
505 memcpy(*refs, tmp, bitmap_size);
509 if (c->object.flags & BOTTOM)
510 continue;
512 if (parse_commit(c))
513 die("unable to parse commit %s",
514 oid_to_hex(&c->object.oid));
516 for (p = c->parents; p; p = p->next) {
517 if (p->item->object.flags & SEEN)
518 continue;
519 commit_list_insert(p->item, &head);
523 nr = get_max_object_index();
524 for (i = 0; i < nr; i++) {
525 struct object *o = get_indexed_object(i);
526 if (o && o->type == OBJ_COMMIT)
527 o->flags &= ~SEEN;
530 free(tmp);
533 static int mark_uninteresting(const char *refname, const struct object_id *oid,
534 int flags, void *cb_data)
536 struct commit *commit = lookup_commit_reference_gently(oid, 1);
537 if (!commit)
538 return 0;
539 commit->object.flags |= UNINTERESTING;
540 mark_parents_uninteresting(commit);
541 return 0;
544 static void post_assign_shallow(struct shallow_info *info,
545 struct ref_bitmap *ref_bitmap,
546 int *ref_status);
548 * Step 6(+7), associate shallow commits with new refs
550 * info->ref must be initialized before calling this function.
552 * If used is not NULL, it's an array of info->shallow->nr
553 * bitmaps. The n-th bit set in the m-th bitmap if ref[n] needs the
554 * m-th shallow commit from info->shallow.
556 * If used is NULL, "ours" and "theirs" are updated. And if ref_status
557 * is not NULL it's an array of ref->nr ints. ref_status[i] is true if
558 * the ref needs some shallow commits from either info->ours or
559 * info->theirs.
561 void assign_shallow_commits_to_refs(struct shallow_info *info,
562 uint32_t **used, int *ref_status)
564 struct object_id *oid = info->shallow->oid;
565 struct oid_array *ref = info->ref;
566 unsigned int i, nr;
567 int *shallow, nr_shallow = 0;
568 struct paint_info pi;
570 trace_printf_key(&trace_shallow, "shallow: assign_shallow_commits_to_refs\n");
571 ALLOC_ARRAY(shallow, info->nr_ours + info->nr_theirs);
572 for (i = 0; i < info->nr_ours; i++)
573 shallow[nr_shallow++] = info->ours[i];
574 for (i = 0; i < info->nr_theirs; i++)
575 shallow[nr_shallow++] = info->theirs[i];
578 * Prepare the commit graph to track what refs can reach what
579 * (new) shallow commits.
581 nr = get_max_object_index();
582 for (i = 0; i < nr; i++) {
583 struct object *o = get_indexed_object(i);
584 if (!o || o->type != OBJ_COMMIT)
585 continue;
587 o->flags &= ~(UNINTERESTING | BOTTOM | SEEN);
590 memset(&pi, 0, sizeof(pi));
591 init_ref_bitmap(&pi.ref_bitmap);
592 pi.nr_bits = ref->nr;
595 * "--not --all" to cut short the traversal if new refs
596 * connect to old refs. If not (e.g. force ref updates) it'll
597 * have to go down to the current shallow commits.
599 head_ref(mark_uninteresting, NULL);
600 for_each_ref(mark_uninteresting, NULL);
602 /* Mark potential bottoms so we won't go out of bound */
603 for (i = 0; i < nr_shallow; i++) {
604 struct commit *c = lookup_commit(&oid[shallow[i]]);
605 c->object.flags |= BOTTOM;
608 for (i = 0; i < ref->nr; i++)
609 paint_down(&pi, ref->oid + i, i);
611 if (used) {
612 int bitmap_size = DIV_ROUND_UP(pi.nr_bits, 32) * sizeof(uint32_t);
613 memset(used, 0, sizeof(*used) * info->shallow->nr);
614 for (i = 0; i < nr_shallow; i++) {
615 const struct commit *c = lookup_commit(&oid[shallow[i]]);
616 uint32_t **map = ref_bitmap_at(&pi.ref_bitmap, c);
617 if (*map)
618 used[shallow[i]] = xmemdupz(*map, bitmap_size);
621 * unreachable shallow commits are not removed from
622 * "ours" and "theirs". The user is supposed to run
623 * step 7 on every ref separately and not trust "ours"
624 * and "theirs" any more.
626 } else
627 post_assign_shallow(info, &pi.ref_bitmap, ref_status);
629 clear_ref_bitmap(&pi.ref_bitmap);
630 for (i = 0; i < pi.pool_count; i++)
631 free(pi.pools[i]);
632 free(pi.pools);
633 free(shallow);
636 struct commit_array {
637 struct commit **commits;
638 int nr, alloc;
641 static int add_ref(const char *refname, const struct object_id *oid,
642 int flags, void *cb_data)
644 struct commit_array *ca = cb_data;
645 ALLOC_GROW(ca->commits, ca->nr + 1, ca->alloc);
646 ca->commits[ca->nr] = lookup_commit_reference_gently(oid, 1);
647 if (ca->commits[ca->nr])
648 ca->nr++;
649 return 0;
652 static void update_refstatus(int *ref_status, int nr, uint32_t *bitmap)
654 unsigned int i;
655 if (!ref_status)
656 return;
657 for (i = 0; i < nr; i++)
658 if (bitmap[i / 32] & (1U << (i % 32)))
659 ref_status[i]++;
663 * Step 7, reachability test on "ours" at commit level
665 static void post_assign_shallow(struct shallow_info *info,
666 struct ref_bitmap *ref_bitmap,
667 int *ref_status)
669 struct object_id *oid = info->shallow->oid;
670 struct commit *c;
671 uint32_t **bitmap;
672 int dst, i, j;
673 int bitmap_nr = DIV_ROUND_UP(info->ref->nr, 32);
674 struct commit_array ca;
676 trace_printf_key(&trace_shallow, "shallow: post_assign_shallow\n");
677 if (ref_status)
678 memset(ref_status, 0, sizeof(*ref_status) * info->ref->nr);
680 /* Remove unreachable shallow commits from "theirs" */
681 for (i = dst = 0; i < info->nr_theirs; i++) {
682 if (i != dst)
683 info->theirs[dst] = info->theirs[i];
684 c = lookup_commit(&oid[info->theirs[i]]);
685 bitmap = ref_bitmap_at(ref_bitmap, c);
686 if (!*bitmap)
687 continue;
688 for (j = 0; j < bitmap_nr; j++)
689 if (bitmap[0][j]) {
690 update_refstatus(ref_status, info->ref->nr, *bitmap);
691 dst++;
692 break;
695 info->nr_theirs = dst;
697 memset(&ca, 0, sizeof(ca));
698 head_ref(add_ref, &ca);
699 for_each_ref(add_ref, &ca);
701 /* Remove unreachable shallow commits from "ours" */
702 for (i = dst = 0; i < info->nr_ours; i++) {
703 if (i != dst)
704 info->ours[dst] = info->ours[i];
705 c = lookup_commit(&oid[info->ours[i]]);
706 bitmap = ref_bitmap_at(ref_bitmap, c);
707 if (!*bitmap)
708 continue;
709 for (j = 0; j < bitmap_nr; j++)
710 if (bitmap[0][j] &&
711 /* Step 7, reachability test at commit level */
712 !in_merge_bases_many(c, ca.nr, ca.commits)) {
713 update_refstatus(ref_status, info->ref->nr, *bitmap);
714 dst++;
715 break;
718 info->nr_ours = dst;
720 free(ca.commits);
723 /* (Delayed) step 7, reachability test at commit level */
724 int delayed_reachability_test(struct shallow_info *si, int c)
726 if (si->need_reachability_test[c]) {
727 struct commit *commit = lookup_commit(&si->shallow->oid[c]);
729 if (!si->commits) {
730 struct commit_array ca;
732 memset(&ca, 0, sizeof(ca));
733 head_ref(add_ref, &ca);
734 for_each_ref(add_ref, &ca);
735 si->commits = ca.commits;
736 si->nr_commits = ca.nr;
739 si->reachable[c] = in_merge_bases_many(commit,
740 si->nr_commits,
741 si->commits);
742 si->need_reachability_test[c] = 0;
744 return si->reachable[c];