object: convert parse_object* to take struct object_id
[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
13 /*
14 * An entry on the bitmap index, representing the bitmap for a given
15 * commit.
16 */
17 struct stored_bitmap {
18 unsigned char sha1[20];
19 struct ewah_bitmap *root;
20 struct stored_bitmap *xor;
21 int flags;
22 };
23
24 /*
25 * The currently active bitmap index. By design, repositories only have
26 * a single bitmap index available (the index for the biggest packfile in
27 * the repository), since bitmap indexes need full closure.
28 *
29 * If there is more than one bitmap index available (e.g. because of alternates),
30 * the active bitmap index is the largest one.
31 */
32 static struct bitmap_index {
33 /* Packfile to which this bitmap index belongs to */
34 struct packed_git *pack;
35
36 /*
37 * Mark the first `reuse_objects` in the packfile as reused:
38 * they will be sent as-is without using them for repacking
39 * calculations
40 */
41 uint32_t reuse_objects;
42
43 /* mmapped buffer of the whole bitmap index */
44 unsigned char *map;
45 size_t map_size; /* size of the mmaped buffer */
46 size_t map_pos; /* current position when loading the index */
47
48 /*
49 * Type indexes.
50 *
51 * Each bitmap marks which objects in the packfile are of the given
52 * type. This provides type information when yielding the objects from
53 * the packfile during a walk, which allows for better delta bases.
54 */
55 struct ewah_bitmap *commits;
56 struct ewah_bitmap *trees;
57 struct ewah_bitmap *blobs;
58 struct ewah_bitmap *tags;
59
60 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped commits */
61 khash_sha1 *bitmaps;
62
63 /* Number of bitmapped commits */
64 uint32_t entry_count;
65
66 /* Name-hash cache (or NULL if not present). */
67 uint32_t *hashes;
68
69 /*
70 * Extended index.
71 *
72 * When trying to perform bitmap operations with objects that are not
73 * packed in `pack`, these objects are added to this "fake index" and
74 * are assumed to appear at the end of the packfile for all operations
75 */
76 struct eindex {
77 struct object **objects;
78 uint32_t *hashes;
79 uint32_t count, alloc;
80 khash_sha1_pos *positions;
81 } ext_index;
82
83 /* Bitmap result of the last performed walk */
84 struct bitmap *result;
85
86 /* Version of the bitmap index */
87 unsigned int version;
88
89 unsigned loaded : 1;
90
91 } bitmap_git;
92
93 static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
94 {
95 struct ewah_bitmap *parent;
96 struct ewah_bitmap *composed;
97
98 if (st->xor == NULL)
99 return st->root;
100
101 composed = ewah_pool_new();
102 parent = lookup_stored_bitmap(st->xor);
103 ewah_xor(st->root, parent, composed);
104
105 ewah_pool_free(st->root);
106 st->root = composed;
107 st->xor = NULL;
108
109 return composed;
110 }
111
112 /*
113 * Read a bitmap from the current read position on the mmaped
114 * index, and increase the read position accordingly
115 */
116 static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)
117 {
118 struct ewah_bitmap *b = ewah_pool_new();
119
120 int bitmap_size = ewah_read_mmap(b,
121 index->map + index->map_pos,
122 index->map_size - index->map_pos);
123
124 if (bitmap_size < 0) {
125 error("Failed to load bitmap index (corrupted?)");
126 ewah_pool_free(b);
127 return NULL;
128 }
129
130 index->map_pos += bitmap_size;
131 return b;
132 }
133
134 static int load_bitmap_header(struct bitmap_index *index)
135 {
136 struct bitmap_disk_header *header = (void *)index->map;
137
138 if (index->map_size < sizeof(*header) + 20)
139 return error("Corrupted bitmap index (missing header data)");
140
141 if (memcmp(header->magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)) != 0)
142 return error("Corrupted bitmap index file (wrong header)");
143
144 index->version = ntohs(header->version);
145 if (index->version != 1)
146 return error("Unsupported version for bitmap index file (%d)", index->version);
147
148 /* Parse known bitmap format options */
149 {
150 uint32_t flags = ntohs(header->options);
151
152 if ((flags & BITMAP_OPT_FULL_DAG) == 0)
153 return error("Unsupported options for bitmap index file "
154 "(Git requires BITMAP_OPT_FULL_DAG)");
155
156 if (flags & BITMAP_OPT_HASH_CACHE) {
157 unsigned char *end = index->map + index->map_size - 20;
158 index->hashes = ((uint32_t *)end) - index->pack->num_objects;
159 }
160 }
161
162 index->entry_count = ntohl(header->entry_count);
163 index->map_pos += sizeof(*header);
164 return 0;
165 }
166
167 static struct stored_bitmap *store_bitmap(struct bitmap_index *index,
168 struct ewah_bitmap *root,
169 const unsigned char *sha1,
170 struct stored_bitmap *xor_with,
171 int flags)
172 {
173 struct stored_bitmap *stored;
174 khiter_t hash_pos;
175 int ret;
176
177 stored = xmalloc(sizeof(struct stored_bitmap));
178 stored->root = root;
179 stored->xor = xor_with;
180 stored->flags = flags;
181 hashcpy(stored->sha1, sha1);
182
183 hash_pos = kh_put_sha1(index->bitmaps, stored->sha1, &ret);
184
185 /* a 0 return code means the insertion succeeded with no changes,
186 * because the SHA1 already existed on the map. this is bad, there
187 * shouldn't be duplicated commits in the index */
188 if (ret == 0) {
189 error("Duplicate entry in bitmap index: %s", sha1_to_hex(sha1));
190 return NULL;
191 }
192
193 kh_value(index->bitmaps, hash_pos) = stored;
194 return stored;
195 }
196
197 static inline uint32_t read_be32(const unsigned char *buffer, size_t *pos)
198 {
199 uint32_t result = get_be32(buffer + *pos);
200 (*pos) += sizeof(result);
201 return result;
202 }
203
204 static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
205 {
206 return buffer[(*pos)++];
207 }
208
209 #define MAX_XOR_OFFSET 160
210
211 static int load_bitmap_entries_v1(struct bitmap_index *index)
212 {
213 uint32_t i;
214 struct stored_bitmap *recent_bitmaps[MAX_XOR_OFFSET] = { NULL };
215
216 for (i = 0; i < index->entry_count; ++i) {
217 int xor_offset, flags;
218 struct ewah_bitmap *bitmap = NULL;
219 struct stored_bitmap *xor_bitmap = NULL;
220 uint32_t commit_idx_pos;
221 const unsigned char *sha1;
222
223 commit_idx_pos = read_be32(index->map, &index->map_pos);
224 xor_offset = read_u8(index->map, &index->map_pos);
225 flags = read_u8(index->map, &index->map_pos);
226
227 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
228
229 bitmap = read_bitmap_1(index);
230 if (!bitmap)
231 return -1;
232
233 if (xor_offset > MAX_XOR_OFFSET || xor_offset > i)
234 return error("Corrupted bitmap pack index");
235
236 if (xor_offset > 0) {
237 xor_bitmap = recent_bitmaps[(i - xor_offset) % MAX_XOR_OFFSET];
238
239 if (xor_bitmap == NULL)
240 return error("Invalid XOR offset in bitmap pack index");
241 }
242
243 recent_bitmaps[i % MAX_XOR_OFFSET] = store_bitmap(
244 index, bitmap, sha1, xor_bitmap, flags);
245 }
246
247 return 0;
248 }
249
250 static char *pack_bitmap_filename(struct packed_git *p)
251 {
252 size_t len;
253
254 if (!strip_suffix(p->pack_name, ".pack", &len))
255 die("BUG: pack_name does not end in .pack");
256 return xstrfmt("%.*s.bitmap", (int)len, p->pack_name);
257 }
258
259 static int open_pack_bitmap_1(struct packed_git *packfile)
260 {
261 int fd;
262 struct stat st;
263 char *idx_name;
264
265 if (open_pack_index(packfile))
266 return -1;
267
268 idx_name = pack_bitmap_filename(packfile);
269 fd = git_open(idx_name);
270 free(idx_name);
271
272 if (fd < 0)
273 return -1;
274
275 if (fstat(fd, &st)) {
276 close(fd);
277 return -1;
278 }
279
280 if (bitmap_git.pack) {
281 warning("ignoring extra bitmap file: %s", packfile->pack_name);
282 close(fd);
283 return -1;
284 }
285
286 bitmap_git.pack = packfile;
287 bitmap_git.map_size = xsize_t(st.st_size);
288 bitmap_git.map = xmmap(NULL, bitmap_git.map_size, PROT_READ, MAP_PRIVATE, fd, 0);
289 bitmap_git.map_pos = 0;
290 close(fd);
291
292 if (load_bitmap_header(&bitmap_git) < 0) {
293 munmap(bitmap_git.map, bitmap_git.map_size);
294 bitmap_git.map = NULL;
295 bitmap_git.map_size = 0;
296 return -1;
297 }
298
299 return 0;
300 }
301
302 static int load_pack_bitmap(void)
303 {
304 assert(bitmap_git.map && !bitmap_git.loaded);
305
306 bitmap_git.bitmaps = kh_init_sha1();
307 bitmap_git.ext_index.positions = kh_init_sha1_pos();
308 load_pack_revindex(bitmap_git.pack);
309
310 if (!(bitmap_git.commits = read_bitmap_1(&bitmap_git)) ||
311 !(bitmap_git.trees = read_bitmap_1(&bitmap_git)) ||
312 !(bitmap_git.blobs = read_bitmap_1(&bitmap_git)) ||
313 !(bitmap_git.tags = read_bitmap_1(&bitmap_git)))
314 goto failed;
315
316 if (load_bitmap_entries_v1(&bitmap_git) < 0)
317 goto failed;
318
319 bitmap_git.loaded = 1;
320 return 0;
321
322 failed:
323 munmap(bitmap_git.map, bitmap_git.map_size);
324 bitmap_git.map = NULL;
325 bitmap_git.map_size = 0;
326 return -1;
327 }
328
329 static int open_pack_bitmap(void)
330 {
331 struct packed_git *p;
332 int ret = -1;
333
334 assert(!bitmap_git.map && !bitmap_git.loaded);
335
336 prepare_packed_git();
337 for (p = packed_git; p; p = p->next) {
338 if (open_pack_bitmap_1(p) == 0)
339 ret = 0;
340 }
341
342 return ret;
343 }
344
345 int prepare_bitmap_git(void)
346 {
347 if (bitmap_git.loaded)
348 return 0;
349
350 if (!open_pack_bitmap())
351 return load_pack_bitmap();
352
353 return -1;
354 }
355
356 struct include_data {
357 struct bitmap *base;
358 struct bitmap *seen;
359 };
360
361 static inline int bitmap_position_extended(const unsigned char *sha1)
362 {
363 khash_sha1_pos *positions = bitmap_git.ext_index.positions;
364 khiter_t pos = kh_get_sha1_pos(positions, sha1);
365
366 if (pos < kh_end(positions)) {
367 int bitmap_pos = kh_value(positions, pos);
368 return bitmap_pos + bitmap_git.pack->num_objects;
369 }
370
371 return -1;
372 }
373
374 static inline int bitmap_position_packfile(const unsigned char *sha1)
375 {
376 off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
377 if (!offset)
378 return -1;
379
380 return find_revindex_position(bitmap_git.pack, offset);
381 }
382
383 static int bitmap_position(const unsigned char *sha1)
384 {
385 int pos = bitmap_position_packfile(sha1);
386 return (pos >= 0) ? pos : bitmap_position_extended(sha1);
387 }
388
389 static int ext_index_add_object(struct object *object, const char *name)
390 {
391 struct eindex *eindex = &bitmap_git.ext_index;
392
393 khiter_t hash_pos;
394 int hash_ret;
395 int bitmap_pos;
396
397 hash_pos = kh_put_sha1_pos(eindex->positions, object->oid.hash, &hash_ret);
398 if (hash_ret > 0) {
399 if (eindex->count >= eindex->alloc) {
400 eindex->alloc = (eindex->alloc + 16) * 3 / 2;
401 REALLOC_ARRAY(eindex->objects, eindex->alloc);
402 REALLOC_ARRAY(eindex->hashes, eindex->alloc);
403 }
404
405 bitmap_pos = eindex->count;
406 eindex->objects[eindex->count] = object;
407 eindex->hashes[eindex->count] = pack_name_hash(name);
408 kh_value(eindex->positions, hash_pos) = bitmap_pos;
409 eindex->count++;
410 } else {
411 bitmap_pos = kh_value(eindex->positions, hash_pos);
412 }
413
414 return bitmap_pos + bitmap_git.pack->num_objects;
415 }
416
417 static void show_object(struct object *object, const char *name, void *data)
418 {
419 struct bitmap *base = data;
420 int bitmap_pos;
421
422 bitmap_pos = bitmap_position(object->oid.hash);
423
424 if (bitmap_pos < 0)
425 bitmap_pos = ext_index_add_object(object, name);
426
427 bitmap_set(base, bitmap_pos);
428 }
429
430 static void show_commit(struct commit *commit, void *data)
431 {
432 }
433
434 static int add_to_include_set(struct include_data *data,
435 const unsigned char *sha1,
436 int bitmap_pos)
437 {
438 khiter_t hash_pos;
439
440 if (data->seen && bitmap_get(data->seen, bitmap_pos))
441 return 0;
442
443 if (bitmap_get(data->base, bitmap_pos))
444 return 0;
445
446 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
447 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
448 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
449 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
450 return 0;
451 }
452
453 bitmap_set(data->base, bitmap_pos);
454 return 1;
455 }
456
457 static int should_include(struct commit *commit, void *_data)
458 {
459 struct include_data *data = _data;
460 int bitmap_pos;
461
462 bitmap_pos = bitmap_position(commit->object.oid.hash);
463 if (bitmap_pos < 0)
464 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
465
466 if (!add_to_include_set(data, commit->object.oid.hash, bitmap_pos)) {
467 struct commit_list *parent = commit->parents;
468
469 while (parent) {
470 parent->item->object.flags |= SEEN;
471 parent = parent->next;
472 }
473
474 return 0;
475 }
476
477 return 1;
478 }
479
480 static struct bitmap *find_objects(struct rev_info *revs,
481 struct object_list *roots,
482 struct bitmap *seen)
483 {
484 struct bitmap *base = NULL;
485 int needs_walk = 0;
486
487 struct object_list *not_mapped = NULL;
488
489 /*
490 * Go through all the roots for the walk. The ones that have bitmaps
491 * on the bitmap index will be `or`ed together to form an initial
492 * global reachability analysis.
493 *
494 * The ones without bitmaps in the index will be stored in the
495 * `not_mapped_list` for further processing.
496 */
497 while (roots) {
498 struct object *object = roots->item;
499 roots = roots->next;
500
501 if (object->type == OBJ_COMMIT) {
502 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->oid.hash);
503
504 if (pos < kh_end(bitmap_git.bitmaps)) {
505 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
506 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
507
508 if (base == NULL)
509 base = ewah_to_bitmap(or_with);
510 else
511 bitmap_or_ewah(base, or_with);
512
513 object->flags |= SEEN;
514 continue;
515 }
516 }
517
518 object_list_insert(object, &not_mapped);
519 }
520
521 /*
522 * Best case scenario: We found bitmaps for all the roots,
523 * so the resulting `or` bitmap has the full reachability analysis
524 */
525 if (not_mapped == NULL)
526 return base;
527
528 roots = not_mapped;
529
530 /*
531 * Let's iterate through all the roots that don't have bitmaps to
532 * check if we can determine them to be reachable from the existing
533 * global bitmap.
534 *
535 * If we cannot find them in the existing global bitmap, we'll need
536 * to push them to an actual walk and run it until we can confirm
537 * they are reachable
538 */
539 while (roots) {
540 struct object *object = roots->item;
541 int pos;
542
543 roots = roots->next;
544 pos = bitmap_position(object->oid.hash);
545
546 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
547 object->flags &= ~UNINTERESTING;
548 add_pending_object(revs, object, "");
549 needs_walk = 1;
550 } else {
551 object->flags |= SEEN;
552 }
553 }
554
555 if (needs_walk) {
556 struct include_data incdata;
557
558 if (base == NULL)
559 base = bitmap_new();
560
561 incdata.base = base;
562 incdata.seen = seen;
563
564 revs->include_check = should_include;
565 revs->include_check_data = &incdata;
566
567 if (prepare_revision_walk(revs))
568 die("revision walk setup failed");
569
570 traverse_commit_list(revs, show_commit, show_object, base);
571 }
572
573 return base;
574 }
575
576 static void show_extended_objects(struct bitmap *objects,
577 show_reachable_fn show_reach)
578 {
579 struct eindex *eindex = &bitmap_git.ext_index;
580 uint32_t i;
581
582 for (i = 0; i < eindex->count; ++i) {
583 struct object *obj;
584
585 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
586 continue;
587
588 obj = eindex->objects[i];
589 show_reach(obj->oid.hash, obj->type, 0, eindex->hashes[i], NULL, 0);
590 }
591 }
592
593 static void show_objects_for_type(
594 struct bitmap *objects,
595 struct ewah_bitmap *type_filter,
596 enum object_type object_type,
597 show_reachable_fn show_reach)
598 {
599 size_t pos = 0, i = 0;
600 uint32_t offset;
601
602 struct ewah_iterator it;
603 eword_t filter;
604
605 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
606 return;
607
608 ewah_iterator_init(&it, type_filter);
609
610 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
611 eword_t word = objects->words[i] & filter;
612
613 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
614 const unsigned char *sha1;
615 struct revindex_entry *entry;
616 uint32_t hash = 0;
617
618 if ((word >> offset) == 0)
619 break;
620
621 offset += ewah_bit_ctz64(word >> offset);
622
623 if (pos + offset < bitmap_git.reuse_objects)
624 continue;
625
626 entry = &bitmap_git.pack->revindex[pos + offset];
627 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
628
629 if (bitmap_git.hashes)
630 hash = ntohl(bitmap_git.hashes[entry->nr]);
631
632 show_reach(sha1, object_type, 0, hash, bitmap_git.pack, entry->offset);
633 }
634
635 pos += BITS_IN_EWORD;
636 i++;
637 }
638 }
639
640 static int in_bitmapped_pack(struct object_list *roots)
641 {
642 while (roots) {
643 struct object *object = roots->item;
644 roots = roots->next;
645
646 if (find_pack_entry_one(object->oid.hash, bitmap_git.pack) > 0)
647 return 1;
648 }
649
650 return 0;
651 }
652
653 int prepare_bitmap_walk(struct rev_info *revs)
654 {
655 unsigned int i;
656 unsigned int pending_nr = revs->pending.nr;
657 struct object_array_entry *pending_e = revs->pending.objects;
658
659 struct object_list *wants = NULL;
660 struct object_list *haves = NULL;
661
662 struct bitmap *wants_bitmap = NULL;
663 struct bitmap *haves_bitmap = NULL;
664
665 if (!bitmap_git.loaded) {
666 /* try to open a bitmapped pack, but don't parse it yet
667 * because we may not need to use it */
668 if (open_pack_bitmap() < 0)
669 return -1;
670 }
671
672 for (i = 0; i < pending_nr; ++i) {
673 struct object *object = pending_e[i].item;
674
675 if (object->type == OBJ_NONE)
676 parse_object_or_die(&object->oid, NULL);
677
678 while (object->type == OBJ_TAG) {
679 struct tag *tag = (struct tag *) object;
680
681 if (object->flags & UNINTERESTING)
682 object_list_insert(object, &haves);
683 else
684 object_list_insert(object, &wants);
685
686 if (!tag->tagged)
687 die("bad tag");
688 object = parse_object_or_die(&tag->tagged->oid, NULL);
689 }
690
691 if (object->flags & UNINTERESTING)
692 object_list_insert(object, &haves);
693 else
694 object_list_insert(object, &wants);
695 }
696
697 /*
698 * if we have a HAVES list, but none of those haves is contained
699 * in the packfile that has a bitmap, we don't have anything to
700 * optimize here
701 */
702 if (haves && !in_bitmapped_pack(haves))
703 return -1;
704
705 /* if we don't want anything, we're done here */
706 if (!wants)
707 return -1;
708
709 /*
710 * now we're going to use bitmaps, so load the actual bitmap entries
711 * from disk. this is the point of no return; after this the rev_list
712 * becomes invalidated and we must perform the revwalk through bitmaps
713 */
714 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
715 return -1;
716
717 revs->pending.nr = 0;
718 revs->pending.alloc = 0;
719 revs->pending.objects = NULL;
720
721 if (haves) {
722 revs->ignore_missing_links = 1;
723 haves_bitmap = find_objects(revs, haves, NULL);
724 reset_revision_walk();
725 revs->ignore_missing_links = 0;
726
727 if (haves_bitmap == NULL)
728 die("BUG: failed to perform bitmap walk");
729 }
730
731 wants_bitmap = find_objects(revs, wants, haves_bitmap);
732
733 if (!wants_bitmap)
734 die("BUG: failed to perform bitmap walk");
735
736 if (haves_bitmap)
737 bitmap_and_not(wants_bitmap, haves_bitmap);
738
739 bitmap_git.result = wants_bitmap;
740
741 bitmap_free(haves_bitmap);
742 return 0;
743 }
744
745 int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
746 uint32_t *entries,
747 off_t *up_to)
748 {
749 /*
750 * Reuse the packfile content if we need more than
751 * 90% of its objects
752 */
753 static const double REUSE_PERCENT = 0.9;
754
755 struct bitmap *result = bitmap_git.result;
756 uint32_t reuse_threshold;
757 uint32_t i, reuse_objects = 0;
758
759 assert(result);
760
761 for (i = 0; i < result->word_alloc; ++i) {
762 if (result->words[i] != (eword_t)~0) {
763 reuse_objects += ewah_bit_ctz64(~result->words[i]);
764 break;
765 }
766
767 reuse_objects += BITS_IN_EWORD;
768 }
769
770 #ifdef GIT_BITMAP_DEBUG
771 {
772 const unsigned char *sha1;
773 struct revindex_entry *entry;
774
775 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
776 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
777
778 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
779 reuse_objects, result->words[i]);
780 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
781 }
782 #endif
783
784 if (!reuse_objects)
785 return -1;
786
787 if (reuse_objects >= bitmap_git.pack->num_objects) {
788 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
789 *up_to = -1; /* reuse the full pack */
790 *packfile = bitmap_git.pack;
791 return 0;
792 }
793
794 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
795
796 if (reuse_objects < reuse_threshold)
797 return -1;
798
799 bitmap_git.reuse_objects = *entries = reuse_objects;
800 *up_to = bitmap_git.pack->revindex[reuse_objects].offset;
801 *packfile = bitmap_git.pack;
802
803 return 0;
804 }
805
806 void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
807 {
808 assert(bitmap_git.result);
809
810 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
811 OBJ_COMMIT, show_reachable);
812 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
813 OBJ_TREE, show_reachable);
814 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
815 OBJ_BLOB, show_reachable);
816 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
817 OBJ_TAG, show_reachable);
818
819 show_extended_objects(bitmap_git.result, show_reachable);
820
821 bitmap_free(bitmap_git.result);
822 bitmap_git.result = NULL;
823 }
824
825 static uint32_t count_object_type(struct bitmap *objects,
826 enum object_type type)
827 {
828 struct eindex *eindex = &bitmap_git.ext_index;
829
830 uint32_t i = 0, count = 0;
831 struct ewah_iterator it;
832 eword_t filter;
833
834 switch (type) {
835 case OBJ_COMMIT:
836 ewah_iterator_init(&it, bitmap_git.commits);
837 break;
838
839 case OBJ_TREE:
840 ewah_iterator_init(&it, bitmap_git.trees);
841 break;
842
843 case OBJ_BLOB:
844 ewah_iterator_init(&it, bitmap_git.blobs);
845 break;
846
847 case OBJ_TAG:
848 ewah_iterator_init(&it, bitmap_git.tags);
849 break;
850
851 default:
852 return 0;
853 }
854
855 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
856 eword_t word = objects->words[i++] & filter;
857 count += ewah_bit_popcount64(word);
858 }
859
860 for (i = 0; i < eindex->count; ++i) {
861 if (eindex->objects[i]->type == type &&
862 bitmap_get(objects, bitmap_git.pack->num_objects + i))
863 count++;
864 }
865
866 return count;
867 }
868
869 void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
870 uint32_t *blobs, uint32_t *tags)
871 {
872 assert(bitmap_git.result);
873
874 if (commits)
875 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
876
877 if (trees)
878 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
879
880 if (blobs)
881 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
882
883 if (tags)
884 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
885 }
886
887 struct bitmap_test_data {
888 struct bitmap *base;
889 struct progress *prg;
890 size_t seen;
891 };
892
893 static void test_show_object(struct object *object, const char *name,
894 void *data)
895 {
896 struct bitmap_test_data *tdata = data;
897 int bitmap_pos;
898
899 bitmap_pos = bitmap_position(object->oid.hash);
900 if (bitmap_pos < 0)
901 die("Object not in bitmap: %s\n", oid_to_hex(&object->oid));
902
903 bitmap_set(tdata->base, bitmap_pos);
904 display_progress(tdata->prg, ++tdata->seen);
905 }
906
907 static void test_show_commit(struct commit *commit, void *data)
908 {
909 struct bitmap_test_data *tdata = data;
910 int bitmap_pos;
911
912 bitmap_pos = bitmap_position(commit->object.oid.hash);
913 if (bitmap_pos < 0)
914 die("Object not in bitmap: %s\n", oid_to_hex(&commit->object.oid));
915
916 bitmap_set(tdata->base, bitmap_pos);
917 display_progress(tdata->prg, ++tdata->seen);
918 }
919
920 void test_bitmap_walk(struct rev_info *revs)
921 {
922 struct object *root;
923 struct bitmap *result = NULL;
924 khiter_t pos;
925 size_t result_popcnt;
926 struct bitmap_test_data tdata;
927
928 if (prepare_bitmap_git())
929 die("failed to load bitmap indexes");
930
931 if (revs->pending.nr != 1)
932 die("you must specify exactly one commit to test");
933
934 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
935 bitmap_git.version, bitmap_git.entry_count);
936
937 root = revs->pending.objects[0].item;
938 pos = kh_get_sha1(bitmap_git.bitmaps, root->oid.hash);
939
940 if (pos < kh_end(bitmap_git.bitmaps)) {
941 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
942 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
943
944 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
945 oid_to_hex(&root->oid), (int)bm->bit_size, ewah_checksum(bm));
946
947 result = ewah_to_bitmap(bm);
948 }
949
950 if (result == NULL)
951 die("Commit %s doesn't have an indexed bitmap", oid_to_hex(&root->oid));
952
953 revs->tag_objects = 1;
954 revs->tree_objects = 1;
955 revs->blob_objects = 1;
956
957 result_popcnt = bitmap_popcount(result);
958
959 if (prepare_revision_walk(revs))
960 die("revision walk setup failed");
961
962 tdata.base = bitmap_new();
963 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
964 tdata.seen = 0;
965
966 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
967
968 stop_progress(&tdata.prg);
969
970 if (bitmap_equals(result, tdata.base))
971 fprintf(stderr, "OK!\n");
972 else
973 fprintf(stderr, "Mismatch!\n");
974
975 bitmap_free(result);
976 }
977
978 static int rebuild_bitmap(uint32_t *reposition,
979 struct ewah_bitmap *source,
980 struct bitmap *dest)
981 {
982 uint32_t pos = 0;
983 struct ewah_iterator it;
984 eword_t word;
985
986 ewah_iterator_init(&it, source);
987
988 while (ewah_iterator_next(&word, &it)) {
989 uint32_t offset, bit_pos;
990
991 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
992 if ((word >> offset) == 0)
993 break;
994
995 offset += ewah_bit_ctz64(word >> offset);
996
997 bit_pos = reposition[pos + offset];
998 if (bit_pos > 0)
999 bitmap_set(dest, bit_pos - 1);
1000 else /* can't reuse, we don't have the object */
1001 return -1;
1002 }
1003
1004 pos += BITS_IN_EWORD;
1005 }
1006 return 0;
1007 }
1008
1009 int rebuild_existing_bitmaps(struct packing_data *mapping,
1010 khash_sha1 *reused_bitmaps,
1011 int show_progress)
1012 {
1013 uint32_t i, num_objects;
1014 uint32_t *reposition;
1015 struct bitmap *rebuild;
1016 struct stored_bitmap *stored;
1017 struct progress *progress = NULL;
1018
1019 khiter_t hash_pos;
1020 int hash_ret;
1021
1022 if (prepare_bitmap_git() < 0)
1023 return -1;
1024
1025 num_objects = bitmap_git.pack->num_objects;
1026 reposition = xcalloc(num_objects, sizeof(uint32_t));
1027
1028 for (i = 0; i < num_objects; ++i) {
1029 const unsigned char *sha1;
1030 struct revindex_entry *entry;
1031 struct object_entry *oe;
1032
1033 entry = &bitmap_git.pack->revindex[i];
1034 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1035 oe = packlist_find(mapping, sha1, NULL);
1036
1037 if (oe)
1038 reposition[i] = oe->in_pack_pos + 1;
1039 }
1040
1041 rebuild = bitmap_new();
1042 i = 0;
1043
1044 if (show_progress)
1045 progress = start_progress("Reusing bitmaps", 0);
1046
1047 kh_foreach_value(bitmap_git.bitmaps, stored, {
1048 if (stored->flags & BITMAP_FLAG_REUSE) {
1049 if (!rebuild_bitmap(reposition,
1050 lookup_stored_bitmap(stored),
1051 rebuild)) {
1052 hash_pos = kh_put_sha1(reused_bitmaps,
1053 stored->sha1,
1054 &hash_ret);
1055 kh_value(reused_bitmaps, hash_pos) =
1056 bitmap_to_ewah(rebuild);
1057 }
1058 bitmap_reset(rebuild);
1059 display_progress(progress, ++i);
1060 }
1061 });
1062
1063 stop_progress(&progress);
1064
1065 free(reposition);
1066 bitmap_free(rebuild);
1067 return 0;
1068 }