git.spec.in: use README.md, not README
[git.git] / pack-bitmap.c
blobdd8dc16e676fb3e928560002c0cb7e1f36910e1a
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"
14 * An entry on the bitmap index, representing the bitmap for a given
15 * commit.
17 struct stored_bitmap {
18 unsigned char sha1[20];
19 struct ewah_bitmap *root;
20 struct stored_bitmap *xor;
21 int flags;
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.
29 * If there is more than one bitmap index available (e.g. because of alternates),
30 * the active bitmap index is the largest one.
32 static struct bitmap_index {
33 /* Packfile to which this bitmap index belongs to */
34 struct packed_git *pack;
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
41 uint32_t reuse_objects;
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 */
49 * Type indexes.
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.
55 struct ewah_bitmap *commits;
56 struct ewah_bitmap *trees;
57 struct ewah_bitmap *blobs;
58 struct ewah_bitmap *tags;
60 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped commits */
61 khash_sha1 *bitmaps;
63 /* Number of bitmapped commits */
64 uint32_t entry_count;
66 /* Name-hash cache (or NULL if not present). */
67 uint32_t *hashes;
70 * Extended index.
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
76 struct eindex {
77 struct object **objects;
78 uint32_t *hashes;
79 uint32_t count, alloc;
80 khash_sha1_pos *positions;
81 } ext_index;
83 /* Bitmap result of the last performed walk */
84 struct bitmap *result;
86 /* Version of the bitmap index */
87 unsigned int version;
89 unsigned loaded : 1;
91 } bitmap_git;
93 static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
95 struct ewah_bitmap *parent;
96 struct ewah_bitmap *composed;
98 if (st->xor == NULL)
99 return st->root;
101 composed = ewah_pool_new();
102 parent = lookup_stored_bitmap(st->xor);
103 ewah_xor(st->root, parent, composed);
105 ewah_pool_free(st->root);
106 st->root = composed;
107 st->xor = NULL;
109 return composed;
113 * Read a bitmap from the current read position on the mmaped
114 * index, and increase the read position accordingly
116 static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)
118 struct ewah_bitmap *b = ewah_pool_new();
120 int bitmap_size = ewah_read_mmap(b,
121 index->map + index->map_pos,
122 index->map_size - index->map_pos);
124 if (bitmap_size < 0) {
125 error("Failed to load bitmap index (corrupted?)");
126 ewah_pool_free(b);
127 return NULL;
130 index->map_pos += bitmap_size;
131 return b;
134 static int load_bitmap_header(struct bitmap_index *index)
136 struct bitmap_disk_header *header = (void *)index->map;
138 if (index->map_size < sizeof(*header) + 20)
139 return error("Corrupted bitmap index (missing header data)");
141 if (memcmp(header->magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)) != 0)
142 return error("Corrupted bitmap index file (wrong header)");
144 index->version = ntohs(header->version);
145 if (index->version != 1)
146 return error("Unsupported version for bitmap index file (%d)", index->version);
148 /* Parse known bitmap format options */
150 uint32_t flags = ntohs(header->options);
152 if ((flags & BITMAP_OPT_FULL_DAG) == 0)
153 return error("Unsupported options for bitmap index file "
154 "(Git requires BITMAP_OPT_FULL_DAG)");
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;
162 index->entry_count = ntohl(header->entry_count);
163 index->map_pos += sizeof(*header);
164 return 0;
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)
173 struct stored_bitmap *stored;
174 khiter_t hash_pos;
175 int ret;
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);
183 hash_pos = kh_put_sha1(index->bitmaps, stored->sha1, &ret);
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;
193 kh_value(index->bitmaps, hash_pos) = stored;
194 return stored;
197 static inline uint32_t read_be32(const unsigned char *buffer, size_t *pos)
199 uint32_t result = get_be32(buffer + *pos);
200 (*pos) += sizeof(result);
201 return result;
204 static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
206 return buffer[(*pos)++];
209 #define MAX_XOR_OFFSET 160
211 static int load_bitmap_entries_v1(struct bitmap_index *index)
213 uint32_t i;
214 struct stored_bitmap *recent_bitmaps[MAX_XOR_OFFSET] = { NULL };
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;
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);
227 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
229 bitmap = read_bitmap_1(index);
230 if (!bitmap)
231 return -1;
233 if (xor_offset > MAX_XOR_OFFSET || xor_offset > i)
234 return error("Corrupted bitmap pack index");
236 if (xor_offset > 0) {
237 xor_bitmap = recent_bitmaps[(i - xor_offset) % MAX_XOR_OFFSET];
239 if (xor_bitmap == NULL)
240 return error("Invalid XOR offset in bitmap pack index");
243 recent_bitmaps[i % MAX_XOR_OFFSET] = store_bitmap(
244 index, bitmap, sha1, xor_bitmap, flags);
247 return 0;
250 static char *pack_bitmap_filename(struct packed_git *p)
252 size_t len;
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);
259 static int open_pack_bitmap_1(struct packed_git *packfile)
261 int fd;
262 struct stat st;
263 char *idx_name;
265 if (open_pack_index(packfile))
266 return -1;
268 idx_name = pack_bitmap_filename(packfile);
269 fd = git_open_noatime(idx_name);
270 free(idx_name);
272 if (fd < 0)
273 return -1;
275 if (fstat(fd, &st)) {
276 close(fd);
277 return -1;
280 if (bitmap_git.pack) {
281 warning("ignoring extra bitmap file: %s", packfile->pack_name);
282 close(fd);
283 return -1;
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);
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;
299 return 0;
302 static int load_pack_bitmap(void)
304 assert(bitmap_git.map && !bitmap_git.loaded);
306 bitmap_git.bitmaps = kh_init_sha1();
307 bitmap_git.ext_index.positions = kh_init_sha1_pos();
308 load_pack_revindex(bitmap_git.pack);
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;
316 if (load_bitmap_entries_v1(&bitmap_git) < 0)
317 goto failed;
319 bitmap_git.loaded = 1;
320 return 0;
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;
329 static int open_pack_bitmap(void)
331 struct packed_git *p;
332 int ret = -1;
334 assert(!bitmap_git.map && !bitmap_git.loaded);
336 prepare_packed_git();
337 for (p = packed_git; p; p = p->next) {
338 if (open_pack_bitmap_1(p) == 0)
339 ret = 0;
342 return ret;
345 int prepare_bitmap_git(void)
347 if (bitmap_git.loaded)
348 return 0;
350 if (!open_pack_bitmap())
351 return load_pack_bitmap();
353 return -1;
356 struct include_data {
357 struct bitmap *base;
358 struct bitmap *seen;
361 static inline int bitmap_position_extended(const unsigned char *sha1)
363 khash_sha1_pos *positions = bitmap_git.ext_index.positions;
364 khiter_t pos = kh_get_sha1_pos(positions, sha1);
366 if (pos < kh_end(positions)) {
367 int bitmap_pos = kh_value(positions, pos);
368 return bitmap_pos + bitmap_git.pack->num_objects;
371 return -1;
374 static inline int bitmap_position_packfile(const unsigned char *sha1)
376 off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
377 if (!offset)
378 return -1;
380 return find_revindex_position(bitmap_git.pack, offset);
383 static int bitmap_position(const unsigned char *sha1)
385 int pos = bitmap_position_packfile(sha1);
386 return (pos >= 0) ? pos : bitmap_position_extended(sha1);
389 static int ext_index_add_object(struct object *object, const char *name)
391 struct eindex *eindex = &bitmap_git.ext_index;
393 khiter_t hash_pos;
394 int hash_ret;
395 int bitmap_pos;
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);
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);
414 return bitmap_pos + bitmap_git.pack->num_objects;
417 static void show_object(struct object *object, const struct name_path *path,
418 const char *last, void *data)
420 struct bitmap *base = data;
421 int bitmap_pos;
423 bitmap_pos = bitmap_position(object->oid.hash);
425 if (bitmap_pos < 0) {
426 char *name = path_name(path, last);
427 bitmap_pos = ext_index_add_object(object, name);
428 free(name);
431 bitmap_set(base, bitmap_pos);
434 static void show_commit(struct commit *commit, void *data)
438 static int add_to_include_set(struct include_data *data,
439 const unsigned char *sha1,
440 int bitmap_pos)
442 khiter_t hash_pos;
444 if (data->seen && bitmap_get(data->seen, bitmap_pos))
445 return 0;
447 if (bitmap_get(data->base, bitmap_pos))
448 return 0;
450 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
451 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
452 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
453 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
454 return 0;
457 bitmap_set(data->base, bitmap_pos);
458 return 1;
461 static int should_include(struct commit *commit, void *_data)
463 struct include_data *data = _data;
464 int bitmap_pos;
466 bitmap_pos = bitmap_position(commit->object.oid.hash);
467 if (bitmap_pos < 0)
468 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
470 if (!add_to_include_set(data, commit->object.oid.hash, bitmap_pos)) {
471 struct commit_list *parent = commit->parents;
473 while (parent) {
474 parent->item->object.flags |= SEEN;
475 parent = parent->next;
478 return 0;
481 return 1;
484 static struct bitmap *find_objects(struct rev_info *revs,
485 struct object_list *roots,
486 struct bitmap *seen)
488 struct bitmap *base = NULL;
489 int needs_walk = 0;
491 struct object_list *not_mapped = NULL;
494 * Go through all the roots for the walk. The ones that have bitmaps
495 * on the bitmap index will be `or`ed together to form an initial
496 * global reachability analysis.
498 * The ones without bitmaps in the index will be stored in the
499 * `not_mapped_list` for further processing.
501 while (roots) {
502 struct object *object = roots->item;
503 roots = roots->next;
505 if (object->type == OBJ_COMMIT) {
506 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->oid.hash);
508 if (pos < kh_end(bitmap_git.bitmaps)) {
509 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
510 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
512 if (base == NULL)
513 base = ewah_to_bitmap(or_with);
514 else
515 bitmap_or_ewah(base, or_with);
517 object->flags |= SEEN;
518 continue;
522 object_list_insert(object, &not_mapped);
526 * Best case scenario: We found bitmaps for all the roots,
527 * so the resulting `or` bitmap has the full reachability analysis
529 if (not_mapped == NULL)
530 return base;
532 roots = not_mapped;
535 * Let's iterate through all the roots that don't have bitmaps to
536 * check if we can determine them to be reachable from the existing
537 * global bitmap.
539 * If we cannot find them in the existing global bitmap, we'll need
540 * to push them to an actual walk and run it until we can confirm
541 * they are reachable
543 while (roots) {
544 struct object *object = roots->item;
545 int pos;
547 roots = roots->next;
548 pos = bitmap_position(object->oid.hash);
550 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
551 object->flags &= ~UNINTERESTING;
552 add_pending_object(revs, object, "");
553 needs_walk = 1;
554 } else {
555 object->flags |= SEEN;
559 if (needs_walk) {
560 struct include_data incdata;
562 if (base == NULL)
563 base = bitmap_new();
565 incdata.base = base;
566 incdata.seen = seen;
568 revs->include_check = should_include;
569 revs->include_check_data = &incdata;
571 if (prepare_revision_walk(revs))
572 die("revision walk setup failed");
574 traverse_commit_list(revs, show_commit, show_object, base);
577 return base;
580 static void show_extended_objects(struct bitmap *objects,
581 show_reachable_fn show_reach)
583 struct eindex *eindex = &bitmap_git.ext_index;
584 uint32_t i;
586 for (i = 0; i < eindex->count; ++i) {
587 struct object *obj;
589 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
590 continue;
592 obj = eindex->objects[i];
593 show_reach(obj->oid.hash, obj->type, 0, eindex->hashes[i], NULL, 0);
597 static void show_objects_for_type(
598 struct bitmap *objects,
599 struct ewah_bitmap *type_filter,
600 enum object_type object_type,
601 show_reachable_fn show_reach)
603 size_t pos = 0, i = 0;
604 uint32_t offset;
606 struct ewah_iterator it;
607 eword_t filter;
609 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
610 return;
612 ewah_iterator_init(&it, type_filter);
614 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
615 eword_t word = objects->words[i] & filter;
617 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
618 const unsigned char *sha1;
619 struct revindex_entry *entry;
620 uint32_t hash = 0;
622 if ((word >> offset) == 0)
623 break;
625 offset += ewah_bit_ctz64(word >> offset);
627 if (pos + offset < bitmap_git.reuse_objects)
628 continue;
630 entry = &bitmap_git.pack->revindex[pos + offset];
631 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
633 if (bitmap_git.hashes)
634 hash = ntohl(bitmap_git.hashes[entry->nr]);
636 show_reach(sha1, object_type, 0, hash, bitmap_git.pack, entry->offset);
639 pos += BITS_IN_EWORD;
640 i++;
644 static int in_bitmapped_pack(struct object_list *roots)
646 while (roots) {
647 struct object *object = roots->item;
648 roots = roots->next;
650 if (find_pack_entry_one(object->oid.hash, bitmap_git.pack) > 0)
651 return 1;
654 return 0;
657 int prepare_bitmap_walk(struct rev_info *revs)
659 unsigned int i;
660 unsigned int pending_nr = revs->pending.nr;
661 struct object_array_entry *pending_e = revs->pending.objects;
663 struct object_list *wants = NULL;
664 struct object_list *haves = NULL;
666 struct bitmap *wants_bitmap = NULL;
667 struct bitmap *haves_bitmap = NULL;
669 if (!bitmap_git.loaded) {
670 /* try to open a bitmapped pack, but don't parse it yet
671 * because we may not need to use it */
672 if (open_pack_bitmap() < 0)
673 return -1;
676 for (i = 0; i < pending_nr; ++i) {
677 struct object *object = pending_e[i].item;
679 if (object->type == OBJ_NONE)
680 parse_object_or_die(object->oid.hash, NULL);
682 while (object->type == OBJ_TAG) {
683 struct tag *tag = (struct tag *) object;
685 if (object->flags & UNINTERESTING)
686 object_list_insert(object, &haves);
687 else
688 object_list_insert(object, &wants);
690 if (!tag->tagged)
691 die("bad tag");
692 object = parse_object_or_die(tag->tagged->oid.hash, NULL);
695 if (object->flags & UNINTERESTING)
696 object_list_insert(object, &haves);
697 else
698 object_list_insert(object, &wants);
702 * if we have a HAVES list, but none of those haves is contained
703 * in the packfile that has a bitmap, we don't have anything to
704 * optimize here
706 if (haves && !in_bitmapped_pack(haves))
707 return -1;
709 /* if we don't want anything, we're done here */
710 if (!wants)
711 return -1;
714 * now we're going to use bitmaps, so load the actual bitmap entries
715 * from disk. this is the point of no return; after this the rev_list
716 * becomes invalidated and we must perform the revwalk through bitmaps
718 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
719 return -1;
721 revs->pending.nr = 0;
722 revs->pending.alloc = 0;
723 revs->pending.objects = NULL;
725 if (haves) {
726 revs->ignore_missing_links = 1;
727 haves_bitmap = find_objects(revs, haves, NULL);
728 reset_revision_walk();
729 revs->ignore_missing_links = 0;
731 if (haves_bitmap == NULL)
732 die("BUG: failed to perform bitmap walk");
735 wants_bitmap = find_objects(revs, wants, haves_bitmap);
737 if (!wants_bitmap)
738 die("BUG: failed to perform bitmap walk");
740 if (haves_bitmap)
741 bitmap_and_not(wants_bitmap, haves_bitmap);
743 bitmap_git.result = wants_bitmap;
745 bitmap_free(haves_bitmap);
746 return 0;
749 int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
750 uint32_t *entries,
751 off_t *up_to)
754 * Reuse the packfile content if we need more than
755 * 90% of its objects
757 static const double REUSE_PERCENT = 0.9;
759 struct bitmap *result = bitmap_git.result;
760 uint32_t reuse_threshold;
761 uint32_t i, reuse_objects = 0;
763 assert(result);
765 for (i = 0; i < result->word_alloc; ++i) {
766 if (result->words[i] != (eword_t)~0) {
767 reuse_objects += ewah_bit_ctz64(~result->words[i]);
768 break;
771 reuse_objects += BITS_IN_EWORD;
774 #ifdef GIT_BITMAP_DEBUG
776 const unsigned char *sha1;
777 struct revindex_entry *entry;
779 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
780 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
782 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
783 reuse_objects, result->words[i]);
784 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
786 #endif
788 if (!reuse_objects)
789 return -1;
791 if (reuse_objects >= bitmap_git.pack->num_objects) {
792 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
793 *up_to = -1; /* reuse the full pack */
794 *packfile = bitmap_git.pack;
795 return 0;
798 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
800 if (reuse_objects < reuse_threshold)
801 return -1;
803 bitmap_git.reuse_objects = *entries = reuse_objects;
804 *up_to = bitmap_git.pack->revindex[reuse_objects].offset;
805 *packfile = bitmap_git.pack;
807 return 0;
810 void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
812 assert(bitmap_git.result);
814 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
815 OBJ_COMMIT, show_reachable);
816 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
817 OBJ_TREE, show_reachable);
818 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
819 OBJ_BLOB, show_reachable);
820 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
821 OBJ_TAG, show_reachable);
823 show_extended_objects(bitmap_git.result, show_reachable);
825 bitmap_free(bitmap_git.result);
826 bitmap_git.result = NULL;
829 static uint32_t count_object_type(struct bitmap *objects,
830 enum object_type type)
832 struct eindex *eindex = &bitmap_git.ext_index;
834 uint32_t i = 0, count = 0;
835 struct ewah_iterator it;
836 eword_t filter;
838 switch (type) {
839 case OBJ_COMMIT:
840 ewah_iterator_init(&it, bitmap_git.commits);
841 break;
843 case OBJ_TREE:
844 ewah_iterator_init(&it, bitmap_git.trees);
845 break;
847 case OBJ_BLOB:
848 ewah_iterator_init(&it, bitmap_git.blobs);
849 break;
851 case OBJ_TAG:
852 ewah_iterator_init(&it, bitmap_git.tags);
853 break;
855 default:
856 return 0;
859 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
860 eword_t word = objects->words[i++] & filter;
861 count += ewah_bit_popcount64(word);
864 for (i = 0; i < eindex->count; ++i) {
865 if (eindex->objects[i]->type == type &&
866 bitmap_get(objects, bitmap_git.pack->num_objects + i))
867 count++;
870 return count;
873 void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
874 uint32_t *blobs, uint32_t *tags)
876 assert(bitmap_git.result);
878 if (commits)
879 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
881 if (trees)
882 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
884 if (blobs)
885 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
887 if (tags)
888 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
891 struct bitmap_test_data {
892 struct bitmap *base;
893 struct progress *prg;
894 size_t seen;
897 static void test_show_object(struct object *object,
898 const struct name_path *path,
899 const char *last, void *data)
901 struct bitmap_test_data *tdata = data;
902 int bitmap_pos;
904 bitmap_pos = bitmap_position(object->oid.hash);
905 if (bitmap_pos < 0)
906 die("Object not in bitmap: %s\n", oid_to_hex(&object->oid));
908 bitmap_set(tdata->base, bitmap_pos);
909 display_progress(tdata->prg, ++tdata->seen);
912 static void test_show_commit(struct commit *commit, void *data)
914 struct bitmap_test_data *tdata = data;
915 int bitmap_pos;
917 bitmap_pos = bitmap_position(commit->object.oid.hash);
918 if (bitmap_pos < 0)
919 die("Object not in bitmap: %s\n", oid_to_hex(&commit->object.oid));
921 bitmap_set(tdata->base, bitmap_pos);
922 display_progress(tdata->prg, ++tdata->seen);
925 void test_bitmap_walk(struct rev_info *revs)
927 struct object *root;
928 struct bitmap *result = NULL;
929 khiter_t pos;
930 size_t result_popcnt;
931 struct bitmap_test_data tdata;
933 if (prepare_bitmap_git())
934 die("failed to load bitmap indexes");
936 if (revs->pending.nr != 1)
937 die("you must specify exactly one commit to test");
939 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
940 bitmap_git.version, bitmap_git.entry_count);
942 root = revs->pending.objects[0].item;
943 pos = kh_get_sha1(bitmap_git.bitmaps, root->oid.hash);
945 if (pos < kh_end(bitmap_git.bitmaps)) {
946 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
947 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
949 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
950 oid_to_hex(&root->oid), (int)bm->bit_size, ewah_checksum(bm));
952 result = ewah_to_bitmap(bm);
955 if (result == NULL)
956 die("Commit %s doesn't have an indexed bitmap", oid_to_hex(&root->oid));
958 revs->tag_objects = 1;
959 revs->tree_objects = 1;
960 revs->blob_objects = 1;
962 result_popcnt = bitmap_popcount(result);
964 if (prepare_revision_walk(revs))
965 die("revision walk setup failed");
967 tdata.base = bitmap_new();
968 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
969 tdata.seen = 0;
971 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
973 stop_progress(&tdata.prg);
975 if (bitmap_equals(result, tdata.base))
976 fprintf(stderr, "OK!\n");
977 else
978 fprintf(stderr, "Mismatch!\n");
980 bitmap_free(result);
983 static int rebuild_bitmap(uint32_t *reposition,
984 struct ewah_bitmap *source,
985 struct bitmap *dest)
987 uint32_t pos = 0;
988 struct ewah_iterator it;
989 eword_t word;
991 ewah_iterator_init(&it, source);
993 while (ewah_iterator_next(&word, &it)) {
994 uint32_t offset, bit_pos;
996 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
997 if ((word >> offset) == 0)
998 break;
1000 offset += ewah_bit_ctz64(word >> offset);
1002 bit_pos = reposition[pos + offset];
1003 if (bit_pos > 0)
1004 bitmap_set(dest, bit_pos - 1);
1005 else /* can't reuse, we don't have the object */
1006 return -1;
1009 pos += BITS_IN_EWORD;
1011 return 0;
1014 int rebuild_existing_bitmaps(struct packing_data *mapping,
1015 khash_sha1 *reused_bitmaps,
1016 int show_progress)
1018 uint32_t i, num_objects;
1019 uint32_t *reposition;
1020 struct bitmap *rebuild;
1021 struct stored_bitmap *stored;
1022 struct progress *progress = NULL;
1024 khiter_t hash_pos;
1025 int hash_ret;
1027 if (prepare_bitmap_git() < 0)
1028 return -1;
1030 num_objects = bitmap_git.pack->num_objects;
1031 reposition = xcalloc(num_objects, sizeof(uint32_t));
1033 for (i = 0; i < num_objects; ++i) {
1034 const unsigned char *sha1;
1035 struct revindex_entry *entry;
1036 struct object_entry *oe;
1038 entry = &bitmap_git.pack->revindex[i];
1039 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1040 oe = packlist_find(mapping, sha1, NULL);
1042 if (oe)
1043 reposition[i] = oe->in_pack_pos + 1;
1046 rebuild = bitmap_new();
1047 i = 0;
1049 if (show_progress)
1050 progress = start_progress("Reusing bitmaps", 0);
1052 kh_foreach_value(bitmap_git.bitmaps, stored, {
1053 if (stored->flags & BITMAP_FLAG_REUSE) {
1054 if (!rebuild_bitmap(reposition,
1055 lookup_stored_bitmap(stored),
1056 rebuild)) {
1057 hash_pos = kh_put_sha1(reused_bitmaps,
1058 stored->sha1,
1059 &hash_ret);
1060 kh_value(reused_bitmaps, hash_pos) =
1061 bitmap_to_ewah(rebuild);
1063 bitmap_reset(rebuild);
1064 display_progress(progress, ++i);
1068 stop_progress(&progress);
1070 free(reposition);
1071 bitmap_free(rebuild);
1072 return 0;