object-store: move packed_git and packed_git_mru to object store
[git/git.git] / pack-bitmap.c
1 #include "cache.h"
2 #include "commit.h"
3 #include "tag.h"
4 #include "diff.h"
5 #include "revision.h"
6 #include "progress.h"
7 #include "list-objects.h"
8 #include "pack.h"
9 #include "pack-bitmap.h"
10 #include "pack-revindex.h"
11 #include "pack-objects.h"
12 #include "packfile.h"
13 #include "repository.h"
14 #include "object-store.h"
15
16 /*
17 * An entry on the bitmap index, representing the bitmap for a given
18 * commit.
19 */
20 struct stored_bitmap {
21 unsigned char sha1[20];
22 struct ewah_bitmap *root;
23 struct stored_bitmap *xor;
24 int flags;
25 };
26
27 /*
28 * The currently active bitmap index. By design, repositories only have
29 * a single bitmap index available (the index for the biggest packfile in
30 * the repository), since bitmap indexes need full closure.
31 *
32 * If there is more than one bitmap index available (e.g. because of alternates),
33 * the active bitmap index is the largest one.
34 */
35 static struct bitmap_index {
36 /* Packfile to which this bitmap index belongs to */
37 struct packed_git *pack;
38
39 /*
40 * Mark the first `reuse_objects` in the packfile as reused:
41 * they will be sent as-is without using them for repacking
42 * calculations
43 */
44 uint32_t reuse_objects;
45
46 /* mmapped buffer of the whole bitmap index */
47 unsigned char *map;
48 size_t map_size; /* size of the mmaped buffer */
49 size_t map_pos; /* current position when loading the index */
50
51 /*
52 * Type indexes.
53 *
54 * Each bitmap marks which objects in the packfile are of the given
55 * type. This provides type information when yielding the objects from
56 * the packfile during a walk, which allows for better delta bases.
57 */
58 struct ewah_bitmap *commits;
59 struct ewah_bitmap *trees;
60 struct ewah_bitmap *blobs;
61 struct ewah_bitmap *tags;
62
63 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped commits */
64 khash_sha1 *bitmaps;
65
66 /* Number of bitmapped commits */
67 uint32_t entry_count;
68
69 /* Name-hash cache (or NULL if not present). */
70 uint32_t *hashes;
71
72 /*
73 * Extended index.
74 *
75 * When trying to perform bitmap operations with objects that are not
76 * packed in `pack`, these objects are added to this "fake index" and
77 * are assumed to appear at the end of the packfile for all operations
78 */
79 struct eindex {
80 struct object **objects;
81 uint32_t *hashes;
82 uint32_t count, alloc;
83 khash_sha1_pos *positions;
84 } ext_index;
85
86 /* Bitmap result of the last performed walk */
87 struct bitmap *result;
88
89 /* Version of the bitmap index */
90 unsigned int version;
91
92 unsigned loaded : 1;
93
94 } bitmap_git;
95
96 static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
97 {
98 struct ewah_bitmap *parent;
99 struct ewah_bitmap *composed;
100
101 if (st->xor == NULL)
102 return st->root;
103
104 composed = ewah_pool_new();
105 parent = lookup_stored_bitmap(st->xor);
106 ewah_xor(st->root, parent, composed);
107
108 ewah_pool_free(st->root);
109 st->root = composed;
110 st->xor = NULL;
111
112 return composed;
113 }
114
115 /*
116 * Read a bitmap from the current read position on the mmaped
117 * index, and increase the read position accordingly
118 */
119 static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)
120 {
121 struct ewah_bitmap *b = ewah_pool_new();
122
123 int bitmap_size = ewah_read_mmap(b,
124 index->map + index->map_pos,
125 index->map_size - index->map_pos);
126
127 if (bitmap_size < 0) {
128 error("Failed to load bitmap index (corrupted?)");
129 ewah_pool_free(b);
130 return NULL;
131 }
132
133 index->map_pos += bitmap_size;
134 return b;
135 }
136
137 static int load_bitmap_header(struct bitmap_index *index)
138 {
139 struct bitmap_disk_header *header = (void *)index->map;
140
141 if (index->map_size < sizeof(*header) + 20)
142 return error("Corrupted bitmap index (missing header data)");
143
144 if (memcmp(header->magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)) != 0)
145 return error("Corrupted bitmap index file (wrong header)");
146
147 index->version = ntohs(header->version);
148 if (index->version != 1)
149 return error("Unsupported version for bitmap index file (%d)", index->version);
150
151 /* Parse known bitmap format options */
152 {
153 uint32_t flags = ntohs(header->options);
154
155 if ((flags & BITMAP_OPT_FULL_DAG) == 0)
156 return error("Unsupported options for bitmap index file "
157 "(Git requires BITMAP_OPT_FULL_DAG)");
158
159 if (flags & BITMAP_OPT_HASH_CACHE) {
160 unsigned char *end = index->map + index->map_size - 20;
161 index->hashes = ((uint32_t *)end) - index->pack->num_objects;
162 }
163 }
164
165 index->entry_count = ntohl(header->entry_count);
166 index->map_pos += sizeof(*header);
167 return 0;
168 }
169
170 static struct stored_bitmap *store_bitmap(struct bitmap_index *index,
171 struct ewah_bitmap *root,
172 const unsigned char *sha1,
173 struct stored_bitmap *xor_with,
174 int flags)
175 {
176 struct stored_bitmap *stored;
177 khiter_t hash_pos;
178 int ret;
179
180 stored = xmalloc(sizeof(struct stored_bitmap));
181 stored->root = root;
182 stored->xor = xor_with;
183 stored->flags = flags;
184 hashcpy(stored->sha1, sha1);
185
186 hash_pos = kh_put_sha1(index->bitmaps, stored->sha1, &ret);
187
188 /* a 0 return code means the insertion succeeded with no changes,
189 * because the SHA1 already existed on the map. this is bad, there
190 * shouldn't be duplicated commits in the index */
191 if (ret == 0) {
192 error("Duplicate entry in bitmap index: %s", sha1_to_hex(sha1));
193 return NULL;
194 }
195
196 kh_value(index->bitmaps, hash_pos) = stored;
197 return stored;
198 }
199
200 static inline uint32_t read_be32(const unsigned char *buffer, size_t *pos)
201 {
202 uint32_t result = get_be32(buffer + *pos);
203 (*pos) += sizeof(result);
204 return result;
205 }
206
207 static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
208 {
209 return buffer[(*pos)++];
210 }
211
212 #define MAX_XOR_OFFSET 160
213
214 static int load_bitmap_entries_v1(struct bitmap_index *index)
215 {
216 uint32_t i;
217 struct stored_bitmap *recent_bitmaps[MAX_XOR_OFFSET] = { NULL };
218
219 for (i = 0; i < index->entry_count; ++i) {
220 int xor_offset, flags;
221 struct ewah_bitmap *bitmap = NULL;
222 struct stored_bitmap *xor_bitmap = NULL;
223 uint32_t commit_idx_pos;
224 const unsigned char *sha1;
225
226 commit_idx_pos = read_be32(index->map, &index->map_pos);
227 xor_offset = read_u8(index->map, &index->map_pos);
228 flags = read_u8(index->map, &index->map_pos);
229
230 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
231
232 bitmap = read_bitmap_1(index);
233 if (!bitmap)
234 return -1;
235
236 if (xor_offset > MAX_XOR_OFFSET || xor_offset > i)
237 return error("Corrupted bitmap pack index");
238
239 if (xor_offset > 0) {
240 xor_bitmap = recent_bitmaps[(i - xor_offset) % MAX_XOR_OFFSET];
241
242 if (xor_bitmap == NULL)
243 return error("Invalid XOR offset in bitmap pack index");
244 }
245
246 recent_bitmaps[i % MAX_XOR_OFFSET] = store_bitmap(
247 index, bitmap, sha1, xor_bitmap, flags);
248 }
249
250 return 0;
251 }
252
253 static char *pack_bitmap_filename(struct packed_git *p)
254 {
255 size_t len;
256
257 if (!strip_suffix(p->pack_name, ".pack", &len))
258 die("BUG: pack_name does not end in .pack");
259 return xstrfmt("%.*s.bitmap", (int)len, p->pack_name);
260 }
261
262 static int open_pack_bitmap_1(struct packed_git *packfile)
263 {
264 int fd;
265 struct stat st;
266 char *idx_name;
267
268 if (open_pack_index(packfile))
269 return -1;
270
271 idx_name = pack_bitmap_filename(packfile);
272 fd = git_open(idx_name);
273 free(idx_name);
274
275 if (fd < 0)
276 return -1;
277
278 if (fstat(fd, &st)) {
279 close(fd);
280 return -1;
281 }
282
283 if (bitmap_git.pack) {
284 warning("ignoring extra bitmap file: %s", packfile->pack_name);
285 close(fd);
286 return -1;
287 }
288
289 bitmap_git.pack = packfile;
290 bitmap_git.map_size = xsize_t(st.st_size);
291 bitmap_git.map = xmmap(NULL, bitmap_git.map_size, PROT_READ, MAP_PRIVATE, fd, 0);
292 bitmap_git.map_pos = 0;
293 close(fd);
294
295 if (load_bitmap_header(&bitmap_git) < 0) {
296 munmap(bitmap_git.map, bitmap_git.map_size);
297 bitmap_git.map = NULL;
298 bitmap_git.map_size = 0;
299 return -1;
300 }
301
302 return 0;
303 }
304
305 static int load_pack_bitmap(void)
306 {
307 assert(bitmap_git.map && !bitmap_git.loaded);
308
309 bitmap_git.bitmaps = kh_init_sha1();
310 bitmap_git.ext_index.positions = kh_init_sha1_pos();
311 load_pack_revindex(bitmap_git.pack);
312
313 if (!(bitmap_git.commits = read_bitmap_1(&bitmap_git)) ||
314 !(bitmap_git.trees = read_bitmap_1(&bitmap_git)) ||
315 !(bitmap_git.blobs = read_bitmap_1(&bitmap_git)) ||
316 !(bitmap_git.tags = read_bitmap_1(&bitmap_git)))
317 goto failed;
318
319 if (load_bitmap_entries_v1(&bitmap_git) < 0)
320 goto failed;
321
322 bitmap_git.loaded = 1;
323 return 0;
324
325 failed:
326 munmap(bitmap_git.map, bitmap_git.map_size);
327 bitmap_git.map = NULL;
328 bitmap_git.map_size = 0;
329 return -1;
330 }
331
332 static int open_pack_bitmap(void)
333 {
334 struct packed_git *p;
335 int ret = -1;
336
337 assert(!bitmap_git.map && !bitmap_git.loaded);
338
339 prepare_packed_git();
340 for (p = get_packed_git(the_repository); p; p = p->next) {
341 if (open_pack_bitmap_1(p) == 0)
342 ret = 0;
343 }
344
345 return ret;
346 }
347
348 int prepare_bitmap_git(void)
349 {
350 if (bitmap_git.loaded)
351 return 0;
352
353 if (!open_pack_bitmap())
354 return load_pack_bitmap();
355
356 return -1;
357 }
358
359 struct include_data {
360 struct bitmap *base;
361 struct bitmap *seen;
362 };
363
364 static inline int bitmap_position_extended(const unsigned char *sha1)
365 {
366 khash_sha1_pos *positions = bitmap_git.ext_index.positions;
367 khiter_t pos = kh_get_sha1_pos(positions, sha1);
368
369 if (pos < kh_end(positions)) {
370 int bitmap_pos = kh_value(positions, pos);
371 return bitmap_pos + bitmap_git.pack->num_objects;
372 }
373
374 return -1;
375 }
376
377 static inline int bitmap_position_packfile(const unsigned char *sha1)
378 {
379 off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
380 if (!offset)
381 return -1;
382
383 return find_revindex_position(bitmap_git.pack, offset);
384 }
385
386 static int bitmap_position(const unsigned char *sha1)
387 {
388 int pos = bitmap_position_packfile(sha1);
389 return (pos >= 0) ? pos : bitmap_position_extended(sha1);
390 }
391
392 static int ext_index_add_object(struct object *object, const char *name)
393 {
394 struct eindex *eindex = &bitmap_git.ext_index;
395
396 khiter_t hash_pos;
397 int hash_ret;
398 int bitmap_pos;
399
400 hash_pos = kh_put_sha1_pos(eindex->positions, object->oid.hash, &hash_ret);
401 if (hash_ret > 0) {
402 if (eindex->count >= eindex->alloc) {
403 eindex->alloc = (eindex->alloc + 16) * 3 / 2;
404 REALLOC_ARRAY(eindex->objects, eindex->alloc);
405 REALLOC_ARRAY(eindex->hashes, eindex->alloc);
406 }
407
408 bitmap_pos = eindex->count;
409 eindex->objects[eindex->count] = object;
410 eindex->hashes[eindex->count] = pack_name_hash(name);
411 kh_value(eindex->positions, hash_pos) = bitmap_pos;
412 eindex->count++;
413 } else {
414 bitmap_pos = kh_value(eindex->positions, hash_pos);
415 }
416
417 return bitmap_pos + bitmap_git.pack->num_objects;
418 }
419
420 static void show_object(struct object *object, const char *name, void *data)
421 {
422 struct bitmap *base = data;
423 int bitmap_pos;
424
425 bitmap_pos = bitmap_position(object->oid.hash);
426
427 if (bitmap_pos < 0)
428 bitmap_pos = ext_index_add_object(object, name);
429
430 bitmap_set(base, bitmap_pos);
431 }
432
433 static void show_commit(struct commit *commit, void *data)
434 {
435 }
436
437 static int add_to_include_set(struct include_data *data,
438 const unsigned char *sha1,
439 int bitmap_pos)
440 {
441 khiter_t hash_pos;
442
443 if (data->seen && bitmap_get(data->seen, bitmap_pos))
444 return 0;
445
446 if (bitmap_get(data->base, bitmap_pos))
447 return 0;
448
449 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
450 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
451 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
452 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
453 return 0;
454 }
455
456 bitmap_set(data->base, bitmap_pos);
457 return 1;
458 }
459
460 static int should_include(struct commit *commit, void *_data)
461 {
462 struct include_data *data = _data;
463 int bitmap_pos;
464
465 bitmap_pos = bitmap_position(commit->object.oid.hash);
466 if (bitmap_pos < 0)
467 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
468
469 if (!add_to_include_set(data, commit->object.oid.hash, bitmap_pos)) {
470 struct commit_list *parent = commit->parents;
471
472 while (parent) {
473 parent->item->object.flags |= SEEN;
474 parent = parent->next;
475 }
476
477 return 0;
478 }
479
480 return 1;
481 }
482
483 static struct bitmap *find_objects(struct rev_info *revs,
484 struct object_list *roots,
485 struct bitmap *seen)
486 {
487 struct bitmap *base = NULL;
488 int needs_walk = 0;
489
490 struct object_list *not_mapped = NULL;
491
492 /*
493 * Go through all the roots for the walk. The ones that have bitmaps
494 * on the bitmap index will be `or`ed together to form an initial
495 * global reachability analysis.
496 *
497 * The ones without bitmaps in the index will be stored in the
498 * `not_mapped_list` for further processing.
499 */
500 while (roots) {
501 struct object *object = roots->item;
502 roots = roots->next;
503
504 if (object->type == OBJ_COMMIT) {
505 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->oid.hash);
506
507 if (pos < kh_end(bitmap_git.bitmaps)) {
508 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
509 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
510
511 if (base == NULL)
512 base = ewah_to_bitmap(or_with);
513 else
514 bitmap_or_ewah(base, or_with);
515
516 object->flags |= SEEN;
517 continue;
518 }
519 }
520
521 object_list_insert(object, &not_mapped);
522 }
523
524 /*
525 * Best case scenario: We found bitmaps for all the roots,
526 * so the resulting `or` bitmap has the full reachability analysis
527 */
528 if (not_mapped == NULL)
529 return base;
530
531 roots = not_mapped;
532
533 /*
534 * Let's iterate through all the roots that don't have bitmaps to
535 * check if we can determine them to be reachable from the existing
536 * global bitmap.
537 *
538 * If we cannot find them in the existing global bitmap, we'll need
539 * to push them to an actual walk and run it until we can confirm
540 * they are reachable
541 */
542 while (roots) {
543 struct object *object = roots->item;
544 int pos;
545
546 roots = roots->next;
547 pos = bitmap_position(object->oid.hash);
548
549 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
550 object->flags &= ~UNINTERESTING;
551 add_pending_object(revs, object, "");
552 needs_walk = 1;
553 } else {
554 object->flags |= SEEN;
555 }
556 }
557
558 if (needs_walk) {
559 struct include_data incdata;
560
561 if (base == NULL)
562 base = bitmap_new();
563
564 incdata.base = base;
565 incdata.seen = seen;
566
567 revs->include_check = should_include;
568 revs->include_check_data = &incdata;
569
570 if (prepare_revision_walk(revs))
571 die("revision walk setup failed");
572
573 traverse_commit_list(revs, show_commit, show_object, base);
574 }
575
576 return base;
577 }
578
579 static void show_extended_objects(struct bitmap *objects,
580 show_reachable_fn show_reach)
581 {
582 struct eindex *eindex = &bitmap_git.ext_index;
583 uint32_t i;
584
585 for (i = 0; i < eindex->count; ++i) {
586 struct object *obj;
587
588 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
589 continue;
590
591 obj = eindex->objects[i];
592 show_reach(&obj->oid, obj->type, 0, eindex->hashes[i], NULL, 0);
593 }
594 }
595
596 static void show_objects_for_type(
597 struct bitmap *objects,
598 struct ewah_bitmap *type_filter,
599 enum object_type object_type,
600 show_reachable_fn show_reach)
601 {
602 size_t pos = 0, i = 0;
603 uint32_t offset;
604
605 struct ewah_iterator it;
606 eword_t filter;
607
608 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
609 return;
610
611 ewah_iterator_init(&it, type_filter);
612
613 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
614 eword_t word = objects->words[i] & filter;
615
616 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
617 struct object_id oid;
618 struct revindex_entry *entry;
619 uint32_t hash = 0;
620
621 if ((word >> offset) == 0)
622 break;
623
624 offset += ewah_bit_ctz64(word >> offset);
625
626 if (pos + offset < bitmap_git.reuse_objects)
627 continue;
628
629 entry = &bitmap_git.pack->revindex[pos + offset];
630 nth_packed_object_oid(&oid, bitmap_git.pack, entry->nr);
631
632 if (bitmap_git.hashes)
633 hash = get_be32(bitmap_git.hashes + entry->nr);
634
635 show_reach(&oid, object_type, 0, hash, bitmap_git.pack, entry->offset);
636 }
637
638 pos += BITS_IN_EWORD;
639 i++;
640 }
641 }
642
643 static int in_bitmapped_pack(struct object_list *roots)
644 {
645 while (roots) {
646 struct object *object = roots->item;
647 roots = roots->next;
648
649 if (find_pack_entry_one(object->oid.hash, bitmap_git.pack) > 0)
650 return 1;
651 }
652
653 return 0;
654 }
655
656 int prepare_bitmap_walk(struct rev_info *revs)
657 {
658 unsigned int i;
659
660 struct object_list *wants = NULL;
661 struct object_list *haves = NULL;
662
663 struct bitmap *wants_bitmap = NULL;
664 struct bitmap *haves_bitmap = NULL;
665
666 if (!bitmap_git.loaded) {
667 /* try to open a bitmapped pack, but don't parse it yet
668 * because we may not need to use it */
669 if (open_pack_bitmap() < 0)
670 return -1;
671 }
672
673 for (i = 0; i < revs->pending.nr; ++i) {
674 struct object *object = revs->pending.objects[i].item;
675
676 if (object->type == OBJ_NONE)
677 parse_object_or_die(&object->oid, NULL);
678
679 while (object->type == OBJ_TAG) {
680 struct tag *tag = (struct tag *) object;
681
682 if (object->flags & UNINTERESTING)
683 object_list_insert(object, &haves);
684 else
685 object_list_insert(object, &wants);
686
687 if (!tag->tagged)
688 die("bad tag");
689 object = parse_object_or_die(&tag->tagged->oid, NULL);
690 }
691
692 if (object->flags & UNINTERESTING)
693 object_list_insert(object, &haves);
694 else
695 object_list_insert(object, &wants);
696 }
697
698 /*
699 * if we have a HAVES list, but none of those haves is contained
700 * in the packfile that has a bitmap, we don't have anything to
701 * optimize here
702 */
703 if (haves && !in_bitmapped_pack(haves))
704 return -1;
705
706 /* if we don't want anything, we're done here */
707 if (!wants)
708 return -1;
709
710 /*
711 * now we're going to use bitmaps, so load the actual bitmap entries
712 * from disk. this is the point of no return; after this the rev_list
713 * becomes invalidated and we must perform the revwalk through bitmaps
714 */
715 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
716 return -1;
717
718 object_array_clear(&revs->pending);
719
720 if (haves) {
721 revs->ignore_missing_links = 1;
722 haves_bitmap = find_objects(revs, haves, NULL);
723 reset_revision_walk();
724 revs->ignore_missing_links = 0;
725
726 if (haves_bitmap == NULL)
727 die("BUG: failed to perform bitmap walk");
728 }
729
730 wants_bitmap = find_objects(revs, wants, haves_bitmap);
731
732 if (!wants_bitmap)
733 die("BUG: failed to perform bitmap walk");
734
735 if (haves_bitmap)
736 bitmap_and_not(wants_bitmap, haves_bitmap);
737
738 bitmap_git.result = wants_bitmap;
739
740 bitmap_free(haves_bitmap);
741 return 0;
742 }
743
744 int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
745 uint32_t *entries,
746 off_t *up_to)
747 {
748 /*
749 * Reuse the packfile content if we need more than
750 * 90% of its objects
751 */
752 static const double REUSE_PERCENT = 0.9;
753
754 struct bitmap *result = bitmap_git.result;
755 uint32_t reuse_threshold;
756 uint32_t i, reuse_objects = 0;
757
758 assert(result);
759
760 for (i = 0; i < result->word_alloc; ++i) {
761 if (result->words[i] != (eword_t)~0) {
762 reuse_objects += ewah_bit_ctz64(~result->words[i]);
763 break;
764 }
765
766 reuse_objects += BITS_IN_EWORD;
767 }
768
769 #ifdef GIT_BITMAP_DEBUG
770 {
771 const unsigned char *sha1;
772 struct revindex_entry *entry;
773
774 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
775 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
776
777 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
778 reuse_objects, result->words[i]);
779 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
780 }
781 #endif
782
783 if (!reuse_objects)
784 return -1;
785
786 if (reuse_objects >= bitmap_git.pack->num_objects) {
787 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
788 *up_to = -1; /* reuse the full pack */
789 *packfile = bitmap_git.pack;
790 return 0;
791 }
792
793 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
794
795 if (reuse_objects < reuse_threshold)
796 return -1;
797
798 bitmap_git.reuse_objects = *entries = reuse_objects;
799 *up_to = bitmap_git.pack->revindex[reuse_objects].offset;
800 *packfile = bitmap_git.pack;
801
802 return 0;
803 }
804
805 void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
806 {
807 assert(bitmap_git.result);
808
809 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
810 OBJ_COMMIT, show_reachable);
811 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
812 OBJ_TREE, show_reachable);
813 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
814 OBJ_BLOB, show_reachable);
815 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
816 OBJ_TAG, show_reachable);
817
818 show_extended_objects(bitmap_git.result, show_reachable);
819
820 bitmap_free(bitmap_git.result);
821 bitmap_git.result = NULL;
822 }
823
824 static uint32_t count_object_type(struct bitmap *objects,
825 enum object_type type)
826 {
827 struct eindex *eindex = &bitmap_git.ext_index;
828
829 uint32_t i = 0, count = 0;
830 struct ewah_iterator it;
831 eword_t filter;
832
833 switch (type) {
834 case OBJ_COMMIT:
835 ewah_iterator_init(&it, bitmap_git.commits);
836 break;
837
838 case OBJ_TREE:
839 ewah_iterator_init(&it, bitmap_git.trees);
840 break;
841
842 case OBJ_BLOB:
843 ewah_iterator_init(&it, bitmap_git.blobs);
844 break;
845
846 case OBJ_TAG:
847 ewah_iterator_init(&it, bitmap_git.tags);
848 break;
849
850 default:
851 return 0;
852 }
853
854 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
855 eword_t word = objects->words[i++] & filter;
856 count += ewah_bit_popcount64(word);
857 }
858
859 for (i = 0; i < eindex->count; ++i) {
860 if (eindex->objects[i]->type == type &&
861 bitmap_get(objects, bitmap_git.pack->num_objects + i))
862 count++;
863 }
864
865 return count;
866 }
867
868 void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
869 uint32_t *blobs, uint32_t *tags)
870 {
871 assert(bitmap_git.result);
872
873 if (commits)
874 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
875
876 if (trees)
877 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
878
879 if (blobs)
880 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
881
882 if (tags)
883 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
884 }
885
886 struct bitmap_test_data {
887 struct bitmap *base;
888 struct progress *prg;
889 size_t seen;
890 };
891
892 static void test_show_object(struct object *object, const char *name,
893 void *data)
894 {
895 struct bitmap_test_data *tdata = data;
896 int bitmap_pos;
897
898 bitmap_pos = bitmap_position(object->oid.hash);
899 if (bitmap_pos < 0)
900 die("Object not in bitmap: %s\n", oid_to_hex(&object->oid));
901
902 bitmap_set(tdata->base, bitmap_pos);
903 display_progress(tdata->prg, ++tdata->seen);
904 }
905
906 static void test_show_commit(struct commit *commit, void *data)
907 {
908 struct bitmap_test_data *tdata = data;
909 int bitmap_pos;
910
911 bitmap_pos = bitmap_position(commit->object.oid.hash);
912 if (bitmap_pos < 0)
913 die("Object not in bitmap: %s\n", oid_to_hex(&commit->object.oid));
914
915 bitmap_set(tdata->base, bitmap_pos);
916 display_progress(tdata->prg, ++tdata->seen);
917 }
918
919 void test_bitmap_walk(struct rev_info *revs)
920 {
921 struct object *root;
922 struct bitmap *result = NULL;
923 khiter_t pos;
924 size_t result_popcnt;
925 struct bitmap_test_data tdata;
926
927 if (prepare_bitmap_git())
928 die("failed to load bitmap indexes");
929
930 if (revs->pending.nr != 1)
931 die("you must specify exactly one commit to test");
932
933 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
934 bitmap_git.version, bitmap_git.entry_count);
935
936 root = revs->pending.objects[0].item;
937 pos = kh_get_sha1(bitmap_git.bitmaps, root->oid.hash);
938
939 if (pos < kh_end(bitmap_git.bitmaps)) {
940 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
941 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
942
943 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
944 oid_to_hex(&root->oid), (int)bm->bit_size, ewah_checksum(bm));
945
946 result = ewah_to_bitmap(bm);
947 }
948
949 if (result == NULL)
950 die("Commit %s doesn't have an indexed bitmap", oid_to_hex(&root->oid));
951
952 revs->tag_objects = 1;
953 revs->tree_objects = 1;
954 revs->blob_objects = 1;
955
956 result_popcnt = bitmap_popcount(result);
957
958 if (prepare_revision_walk(revs))
959 die("revision walk setup failed");
960
961 tdata.base = bitmap_new();
962 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
963 tdata.seen = 0;
964
965 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
966
967 stop_progress(&tdata.prg);
968
969 if (bitmap_equals(result, tdata.base))
970 fprintf(stderr, "OK!\n");
971 else
972 fprintf(stderr, "Mismatch!\n");
973
974 bitmap_free(result);
975 }
976
977 static int rebuild_bitmap(uint32_t *reposition,
978 struct ewah_bitmap *source,
979 struct bitmap *dest)
980 {
981 uint32_t pos = 0;
982 struct ewah_iterator it;
983 eword_t word;
984
985 ewah_iterator_init(&it, source);
986
987 while (ewah_iterator_next(&word, &it)) {
988 uint32_t offset, bit_pos;
989
990 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
991 if ((word >> offset) == 0)
992 break;
993
994 offset += ewah_bit_ctz64(word >> offset);
995
996 bit_pos = reposition[pos + offset];
997 if (bit_pos > 0)
998 bitmap_set(dest, bit_pos - 1);
999 else /* can't reuse, we don't have the object */
1000 return -1;
1001 }
1002
1003 pos += BITS_IN_EWORD;
1004 }
1005 return 0;
1006 }
1007
1008 int rebuild_existing_bitmaps(struct packing_data *mapping,
1009 khash_sha1 *reused_bitmaps,
1010 int show_progress)
1011 {
1012 uint32_t i, num_objects;
1013 uint32_t *reposition;
1014 struct bitmap *rebuild;
1015 struct stored_bitmap *stored;
1016 struct progress *progress = NULL;
1017
1018 khiter_t hash_pos;
1019 int hash_ret;
1020
1021 if (prepare_bitmap_git() < 0)
1022 return -1;
1023
1024 num_objects = bitmap_git.pack->num_objects;
1025 reposition = xcalloc(num_objects, sizeof(uint32_t));
1026
1027 for (i = 0; i < num_objects; ++i) {
1028 const unsigned char *sha1;
1029 struct revindex_entry *entry;
1030 struct object_entry *oe;
1031
1032 entry = &bitmap_git.pack->revindex[i];
1033 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1034 oe = packlist_find(mapping, sha1, NULL);
1035
1036 if (oe)
1037 reposition[i] = oe->in_pack_pos + 1;
1038 }
1039
1040 rebuild = bitmap_new();
1041 i = 0;
1042
1043 if (show_progress)
1044 progress = start_progress("Reusing bitmaps", 0);
1045
1046 kh_foreach_value(bitmap_git.bitmaps, stored, {
1047 if (stored->flags & BITMAP_FLAG_REUSE) {
1048 if (!rebuild_bitmap(reposition,
1049 lookup_stored_bitmap(stored),
1050 rebuild)) {
1051 hash_pos = kh_put_sha1(reused_bitmaps,
1052 stored->sha1,
1053 &hash_ret);
1054 kh_value(reused_bitmaps, hash_pos) =
1055 bitmap_to_ewah(rebuild);
1056 }
1057 bitmap_reset(rebuild);
1058 display_progress(progress, ++i);
1059 }
1060 });
1061
1062 stop_progress(&progress);
1063
1064 free(reposition);
1065 bitmap_free(rebuild);
1066 return 0;
1067 }