git: treat "git -C '<path>'" as a no-op when <path> is empty
[git.git] / pack-bitmap.c
blob6a818419ca46f8d66adbeb0027da49e6bab1bfa3
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;
36 /* reverse index for the packfile */
37 struct pack_revindex *reverse_index;
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
44 uint32_t reuse_objects;
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 */
52 * Type indexes.
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.
58 struct ewah_bitmap *commits;
59 struct ewah_bitmap *trees;
60 struct ewah_bitmap *blobs;
61 struct ewah_bitmap *tags;
63 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped comits */
64 khash_sha1 *bitmaps;
66 /* Number of bitmapped commits */
67 uint32_t entry_count;
69 /* Name-hash cache (or NULL if not present). */
70 uint32_t *hashes;
73 * Extended index.
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
79 struct eindex {
80 struct object **objects;
81 uint32_t *hashes;
82 uint32_t count, alloc;
83 khash_sha1_pos *positions;
84 } ext_index;
86 /* Bitmap result of the last performed walk */
87 struct bitmap *result;
89 /* Version of the bitmap index */
90 unsigned int version;
92 unsigned loaded : 1;
94 } bitmap_git;
96 static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
98 struct ewah_bitmap *parent;
99 struct ewah_bitmap *composed;
101 if (st->xor == NULL)
102 return st->root;
104 composed = ewah_pool_new();
105 parent = lookup_stored_bitmap(st->xor);
106 ewah_xor(st->root, parent, composed);
108 ewah_pool_free(st->root);
109 st->root = composed;
110 st->xor = NULL;
112 return composed;
116 * Read a bitmap from the current read position on the mmaped
117 * index, and increase the read position accordingly
119 static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)
121 struct ewah_bitmap *b = ewah_pool_new();
123 int bitmap_size = ewah_read_mmap(b,
124 index->map + index->map_pos,
125 index->map_size - index->map_pos);
127 if (bitmap_size < 0) {
128 error("Failed to load bitmap index (corrupted?)");
129 ewah_pool_free(b);
130 return NULL;
133 index->map_pos += bitmap_size;
134 return b;
137 static int load_bitmap_header(struct bitmap_index *index)
139 struct bitmap_disk_header *header = (void *)index->map;
141 if (index->map_size < sizeof(*header) + 20)
142 return error("Corrupted bitmap index (missing header data)");
144 if (memcmp(header->magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)) != 0)
145 return error("Corrupted bitmap index file (wrong header)");
147 index->version = ntohs(header->version);
148 if (index->version != 1)
149 return error("Unsupported version for bitmap index file (%d)", index->version);
151 /* Parse known bitmap format options */
153 uint32_t flags = ntohs(header->options);
155 if ((flags & BITMAP_OPT_FULL_DAG) == 0)
156 return error("Unsupported options for bitmap index file "
157 "(Git requires BITMAP_OPT_FULL_DAG)");
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;
165 index->entry_count = ntohl(header->entry_count);
166 index->map_pos += sizeof(*header);
167 return 0;
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)
176 struct stored_bitmap *stored;
177 khiter_t hash_pos;
178 int ret;
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);
186 hash_pos = kh_put_sha1(index->bitmaps, stored->sha1, &ret);
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;
196 kh_value(index->bitmaps, hash_pos) = stored;
197 return stored;
200 static inline uint32_t read_be32(const unsigned char *buffer, size_t *pos)
202 uint32_t result = get_be32(buffer + *pos);
203 (*pos) += sizeof(result);
204 return result;
207 static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
209 return buffer[(*pos)++];
212 static int load_bitmap_entries_v1(struct bitmap_index *index)
214 static const size_t MAX_XOR_OFFSET = 160;
216 uint32_t i;
217 struct stored_bitmap **recent_bitmaps;
219 recent_bitmaps = xcalloc(MAX_XOR_OFFSET, sizeof(struct stored_bitmap));
221 for (i = 0; i < index->entry_count; ++i) {
222 int xor_offset, flags;
223 struct ewah_bitmap *bitmap = NULL;
224 struct stored_bitmap *xor_bitmap = NULL;
225 uint32_t commit_idx_pos;
226 const unsigned char *sha1;
228 commit_idx_pos = read_be32(index->map, &index->map_pos);
229 xor_offset = read_u8(index->map, &index->map_pos);
230 flags = read_u8(index->map, &index->map_pos);
232 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
234 bitmap = read_bitmap_1(index);
235 if (!bitmap)
236 return -1;
238 if (xor_offset > MAX_XOR_OFFSET || xor_offset > i)
239 return error("Corrupted bitmap pack index");
241 if (xor_offset > 0) {
242 xor_bitmap = recent_bitmaps[(i - xor_offset) % MAX_XOR_OFFSET];
244 if (xor_bitmap == NULL)
245 return error("Invalid XOR offset in bitmap pack index");
248 recent_bitmaps[i % MAX_XOR_OFFSET] = store_bitmap(
249 index, bitmap, sha1, xor_bitmap, flags);
252 return 0;
255 static int open_pack_bitmap_1(struct packed_git *packfile)
257 int fd;
258 struct stat st;
259 char *idx_name;
261 if (open_pack_index(packfile))
262 return -1;
264 idx_name = pack_bitmap_filename(packfile);
265 fd = git_open_noatime(idx_name);
266 free(idx_name);
268 if (fd < 0)
269 return -1;
271 if (fstat(fd, &st)) {
272 close(fd);
273 return -1;
276 if (bitmap_git.pack) {
277 warning("ignoring extra bitmap file: %s", packfile->pack_name);
278 close(fd);
279 return -1;
282 bitmap_git.pack = packfile;
283 bitmap_git.map_size = xsize_t(st.st_size);
284 bitmap_git.map = xmmap(NULL, bitmap_git.map_size, PROT_READ, MAP_PRIVATE, fd, 0);
285 bitmap_git.map_pos = 0;
286 close(fd);
288 if (load_bitmap_header(&bitmap_git) < 0) {
289 munmap(bitmap_git.map, bitmap_git.map_size);
290 bitmap_git.map = NULL;
291 bitmap_git.map_size = 0;
292 return -1;
295 return 0;
298 static int load_pack_bitmap(void)
300 assert(bitmap_git.map && !bitmap_git.loaded);
302 bitmap_git.bitmaps = kh_init_sha1();
303 bitmap_git.ext_index.positions = kh_init_sha1_pos();
304 bitmap_git.reverse_index = revindex_for_pack(bitmap_git.pack);
306 if (!(bitmap_git.commits = read_bitmap_1(&bitmap_git)) ||
307 !(bitmap_git.trees = read_bitmap_1(&bitmap_git)) ||
308 !(bitmap_git.blobs = read_bitmap_1(&bitmap_git)) ||
309 !(bitmap_git.tags = read_bitmap_1(&bitmap_git)))
310 goto failed;
312 if (load_bitmap_entries_v1(&bitmap_git) < 0)
313 goto failed;
315 bitmap_git.loaded = 1;
316 return 0;
318 failed:
319 munmap(bitmap_git.map, bitmap_git.map_size);
320 bitmap_git.map = NULL;
321 bitmap_git.map_size = 0;
322 return -1;
325 char *pack_bitmap_filename(struct packed_git *p)
327 char *idx_name;
328 int len;
330 len = strlen(p->pack_name) - strlen(".pack");
331 idx_name = xmalloc(len + strlen(".bitmap") + 1);
333 memcpy(idx_name, p->pack_name, len);
334 memcpy(idx_name + len, ".bitmap", strlen(".bitmap") + 1);
336 return idx_name;
339 static int open_pack_bitmap(void)
341 struct packed_git *p;
342 int ret = -1;
344 assert(!bitmap_git.map && !bitmap_git.loaded);
346 prepare_packed_git();
347 for (p = packed_git; p; p = p->next) {
348 if (open_pack_bitmap_1(p) == 0)
349 ret = 0;
352 return ret;
355 int prepare_bitmap_git(void)
357 if (bitmap_git.loaded)
358 return 0;
360 if (!open_pack_bitmap())
361 return load_pack_bitmap();
363 return -1;
366 struct include_data {
367 struct bitmap *base;
368 struct bitmap *seen;
371 static inline int bitmap_position_extended(const unsigned char *sha1)
373 khash_sha1_pos *positions = bitmap_git.ext_index.positions;
374 khiter_t pos = kh_get_sha1_pos(positions, sha1);
376 if (pos < kh_end(positions)) {
377 int bitmap_pos = kh_value(positions, pos);
378 return bitmap_pos + bitmap_git.pack->num_objects;
381 return -1;
384 static inline int bitmap_position_packfile(const unsigned char *sha1)
386 off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
387 if (!offset)
388 return -1;
390 return find_revindex_position(bitmap_git.reverse_index, offset);
393 static int bitmap_position(const unsigned char *sha1)
395 int pos = bitmap_position_packfile(sha1);
396 return (pos >= 0) ? pos : bitmap_position_extended(sha1);
399 static int ext_index_add_object(struct object *object, const char *name)
401 struct eindex *eindex = &bitmap_git.ext_index;
403 khiter_t hash_pos;
404 int hash_ret;
405 int bitmap_pos;
407 hash_pos = kh_put_sha1_pos(eindex->positions, object->sha1, &hash_ret);
408 if (hash_ret > 0) {
409 if (eindex->count >= eindex->alloc) {
410 eindex->alloc = (eindex->alloc + 16) * 3 / 2;
411 REALLOC_ARRAY(eindex->objects, eindex->alloc);
412 REALLOC_ARRAY(eindex->hashes, eindex->alloc);
415 bitmap_pos = eindex->count;
416 eindex->objects[eindex->count] = object;
417 eindex->hashes[eindex->count] = pack_name_hash(name);
418 kh_value(eindex->positions, hash_pos) = bitmap_pos;
419 eindex->count++;
420 } else {
421 bitmap_pos = kh_value(eindex->positions, hash_pos);
424 return bitmap_pos + bitmap_git.pack->num_objects;
427 static void show_object(struct object *object, const struct name_path *path,
428 const char *last, void *data)
430 struct bitmap *base = data;
431 int bitmap_pos;
433 bitmap_pos = bitmap_position(object->sha1);
435 if (bitmap_pos < 0) {
436 char *name = path_name(path, last);
437 bitmap_pos = ext_index_add_object(object, name);
438 free(name);
441 bitmap_set(base, bitmap_pos);
444 static void show_commit(struct commit *commit, void *data)
448 static int add_to_include_set(struct include_data *data,
449 const unsigned char *sha1,
450 int bitmap_pos)
452 khiter_t hash_pos;
454 if (data->seen && bitmap_get(data->seen, bitmap_pos))
455 return 0;
457 if (bitmap_get(data->base, bitmap_pos))
458 return 0;
460 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
461 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
462 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
463 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
464 return 0;
467 bitmap_set(data->base, bitmap_pos);
468 return 1;
471 static int should_include(struct commit *commit, void *_data)
473 struct include_data *data = _data;
474 int bitmap_pos;
476 bitmap_pos = bitmap_position(commit->object.sha1);
477 if (bitmap_pos < 0)
478 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
480 if (!add_to_include_set(data, commit->object.sha1, bitmap_pos)) {
481 struct commit_list *parent = commit->parents;
483 while (parent) {
484 parent->item->object.flags |= SEEN;
485 parent = parent->next;
488 return 0;
491 return 1;
494 static struct bitmap *find_objects(struct rev_info *revs,
495 struct object_list *roots,
496 struct bitmap *seen)
498 struct bitmap *base = NULL;
499 int needs_walk = 0;
501 struct object_list *not_mapped = NULL;
504 * Go through all the roots for the walk. The ones that have bitmaps
505 * on the bitmap index will be `or`ed together to form an initial
506 * global reachability analysis.
508 * The ones without bitmaps in the index will be stored in the
509 * `not_mapped_list` for further processing.
511 while (roots) {
512 struct object *object = roots->item;
513 roots = roots->next;
515 if (object->type == OBJ_COMMIT) {
516 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->sha1);
518 if (pos < kh_end(bitmap_git.bitmaps)) {
519 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
520 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
522 if (base == NULL)
523 base = ewah_to_bitmap(or_with);
524 else
525 bitmap_or_ewah(base, or_with);
527 object->flags |= SEEN;
528 continue;
532 object_list_insert(object, &not_mapped);
536 * Best case scenario: We found bitmaps for all the roots,
537 * so the resulting `or` bitmap has the full reachability analysis
539 if (not_mapped == NULL)
540 return base;
542 roots = not_mapped;
545 * Let's iterate through all the roots that don't have bitmaps to
546 * check if we can determine them to be reachable from the existing
547 * global bitmap.
549 * If we cannot find them in the existing global bitmap, we'll need
550 * to push them to an actual walk and run it until we can confirm
551 * they are reachable
553 while (roots) {
554 struct object *object = roots->item;
555 int pos;
557 roots = roots->next;
558 pos = bitmap_position(object->sha1);
560 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
561 object->flags &= ~UNINTERESTING;
562 add_pending_object(revs, object, "");
563 needs_walk = 1;
564 } else {
565 object->flags |= SEEN;
569 if (needs_walk) {
570 struct include_data incdata;
572 if (base == NULL)
573 base = bitmap_new();
575 incdata.base = base;
576 incdata.seen = seen;
578 revs->include_check = should_include;
579 revs->include_check_data = &incdata;
581 if (prepare_revision_walk(revs))
582 die("revision walk setup failed");
584 traverse_commit_list(revs, show_commit, show_object, base);
587 return base;
590 static void show_extended_objects(struct bitmap *objects,
591 show_reachable_fn show_reach)
593 struct eindex *eindex = &bitmap_git.ext_index;
594 uint32_t i;
596 for (i = 0; i < eindex->count; ++i) {
597 struct object *obj;
599 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
600 continue;
602 obj = eindex->objects[i];
603 show_reach(obj->sha1, obj->type, 0, eindex->hashes[i], NULL, 0);
607 static void show_objects_for_type(
608 struct bitmap *objects,
609 struct ewah_bitmap *type_filter,
610 enum object_type object_type,
611 show_reachable_fn show_reach)
613 size_t pos = 0, i = 0;
614 uint32_t offset;
616 struct ewah_iterator it;
617 eword_t filter;
619 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
620 return;
622 ewah_iterator_init(&it, type_filter);
624 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
625 eword_t word = objects->words[i] & filter;
627 for (offset = 0; offset < BITS_IN_WORD; ++offset) {
628 const unsigned char *sha1;
629 struct revindex_entry *entry;
630 uint32_t hash = 0;
632 if ((word >> offset) == 0)
633 break;
635 offset += ewah_bit_ctz64(word >> offset);
637 if (pos + offset < bitmap_git.reuse_objects)
638 continue;
640 entry = &bitmap_git.reverse_index->revindex[pos + offset];
641 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
643 if (bitmap_git.hashes)
644 hash = ntohl(bitmap_git.hashes[entry->nr]);
646 show_reach(sha1, object_type, 0, hash, bitmap_git.pack, entry->offset);
649 pos += BITS_IN_WORD;
650 i++;
654 static int in_bitmapped_pack(struct object_list *roots)
656 while (roots) {
657 struct object *object = roots->item;
658 roots = roots->next;
660 if (find_pack_entry_one(object->sha1, bitmap_git.pack) > 0)
661 return 1;
664 return 0;
667 int prepare_bitmap_walk(struct rev_info *revs)
669 unsigned int i;
670 unsigned int pending_nr = revs->pending.nr;
671 struct object_array_entry *pending_e = revs->pending.objects;
673 struct object_list *wants = NULL;
674 struct object_list *haves = NULL;
676 struct bitmap *wants_bitmap = NULL;
677 struct bitmap *haves_bitmap = NULL;
679 if (!bitmap_git.loaded) {
680 /* try to open a bitmapped pack, but don't parse it yet
681 * because we may not need to use it */
682 if (open_pack_bitmap() < 0)
683 return -1;
686 for (i = 0; i < pending_nr; ++i) {
687 struct object *object = pending_e[i].item;
689 if (object->type == OBJ_NONE)
690 parse_object_or_die(object->sha1, NULL);
692 while (object->type == OBJ_TAG) {
693 struct tag *tag = (struct tag *) object;
695 if (object->flags & UNINTERESTING)
696 object_list_insert(object, &haves);
697 else
698 object_list_insert(object, &wants);
700 if (!tag->tagged)
701 die("bad tag");
702 object = parse_object_or_die(tag->tagged->sha1, NULL);
705 if (object->flags & UNINTERESTING)
706 object_list_insert(object, &haves);
707 else
708 object_list_insert(object, &wants);
712 * if we have a HAVES list, but none of those haves is contained
713 * in the packfile that has a bitmap, we don't have anything to
714 * optimize here
716 if (haves && !in_bitmapped_pack(haves))
717 return -1;
719 /* if we don't want anything, we're done here */
720 if (!wants)
721 return -1;
724 * now we're going to use bitmaps, so load the actual bitmap entries
725 * from disk. this is the point of no return; after this the rev_list
726 * becomes invalidated and we must perform the revwalk through bitmaps
728 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
729 return -1;
731 revs->pending.nr = 0;
732 revs->pending.alloc = 0;
733 revs->pending.objects = NULL;
735 if (haves) {
736 revs->ignore_missing_links = 1;
737 haves_bitmap = find_objects(revs, haves, NULL);
738 reset_revision_walk();
739 revs->ignore_missing_links = 0;
741 if (haves_bitmap == NULL)
742 die("BUG: failed to perform bitmap walk");
745 wants_bitmap = find_objects(revs, wants, haves_bitmap);
747 if (!wants_bitmap)
748 die("BUG: failed to perform bitmap walk");
750 if (haves_bitmap)
751 bitmap_and_not(wants_bitmap, haves_bitmap);
753 bitmap_git.result = wants_bitmap;
755 bitmap_free(haves_bitmap);
756 return 0;
759 int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
760 uint32_t *entries,
761 off_t *up_to)
764 * Reuse the packfile content if we need more than
765 * 90% of its objects
767 static const double REUSE_PERCENT = 0.9;
769 struct bitmap *result = bitmap_git.result;
770 uint32_t reuse_threshold;
771 uint32_t i, reuse_objects = 0;
773 assert(result);
775 for (i = 0; i < result->word_alloc; ++i) {
776 if (result->words[i] != (eword_t)~0) {
777 reuse_objects += ewah_bit_ctz64(~result->words[i]);
778 break;
781 reuse_objects += BITS_IN_WORD;
784 #ifdef GIT_BITMAP_DEBUG
786 const unsigned char *sha1;
787 struct revindex_entry *entry;
789 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
790 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
792 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
793 reuse_objects, result->words[i]);
794 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
796 #endif
798 if (!reuse_objects)
799 return -1;
801 if (reuse_objects >= bitmap_git.pack->num_objects) {
802 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
803 *up_to = -1; /* reuse the full pack */
804 *packfile = bitmap_git.pack;
805 return 0;
808 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
810 if (reuse_objects < reuse_threshold)
811 return -1;
813 bitmap_git.reuse_objects = *entries = reuse_objects;
814 *up_to = bitmap_git.reverse_index->revindex[reuse_objects].offset;
815 *packfile = bitmap_git.pack;
817 return 0;
820 void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
822 assert(bitmap_git.result);
824 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
825 OBJ_COMMIT, show_reachable);
826 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
827 OBJ_TREE, show_reachable);
828 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
829 OBJ_BLOB, show_reachable);
830 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
831 OBJ_TAG, show_reachable);
833 show_extended_objects(bitmap_git.result, show_reachable);
835 bitmap_free(bitmap_git.result);
836 bitmap_git.result = NULL;
839 static uint32_t count_object_type(struct bitmap *objects,
840 enum object_type type)
842 struct eindex *eindex = &bitmap_git.ext_index;
844 uint32_t i = 0, count = 0;
845 struct ewah_iterator it;
846 eword_t filter;
848 switch (type) {
849 case OBJ_COMMIT:
850 ewah_iterator_init(&it, bitmap_git.commits);
851 break;
853 case OBJ_TREE:
854 ewah_iterator_init(&it, bitmap_git.trees);
855 break;
857 case OBJ_BLOB:
858 ewah_iterator_init(&it, bitmap_git.blobs);
859 break;
861 case OBJ_TAG:
862 ewah_iterator_init(&it, bitmap_git.tags);
863 break;
865 default:
866 return 0;
869 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
870 eword_t word = objects->words[i++] & filter;
871 count += ewah_bit_popcount64(word);
874 for (i = 0; i < eindex->count; ++i) {
875 if (eindex->objects[i]->type == type &&
876 bitmap_get(objects, bitmap_git.pack->num_objects + i))
877 count++;
880 return count;
883 void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
884 uint32_t *blobs, uint32_t *tags)
886 assert(bitmap_git.result);
888 if (commits)
889 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
891 if (trees)
892 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
894 if (blobs)
895 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
897 if (tags)
898 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
901 struct bitmap_test_data {
902 struct bitmap *base;
903 struct progress *prg;
904 size_t seen;
907 static void test_show_object(struct object *object,
908 const struct name_path *path,
909 const char *last, void *data)
911 struct bitmap_test_data *tdata = data;
912 int bitmap_pos;
914 bitmap_pos = bitmap_position(object->sha1);
915 if (bitmap_pos < 0)
916 die("Object not in bitmap: %s\n", sha1_to_hex(object->sha1));
918 bitmap_set(tdata->base, bitmap_pos);
919 display_progress(tdata->prg, ++tdata->seen);
922 static void test_show_commit(struct commit *commit, void *data)
924 struct bitmap_test_data *tdata = data;
925 int bitmap_pos;
927 bitmap_pos = bitmap_position(commit->object.sha1);
928 if (bitmap_pos < 0)
929 die("Object not in bitmap: %s\n", sha1_to_hex(commit->object.sha1));
931 bitmap_set(tdata->base, bitmap_pos);
932 display_progress(tdata->prg, ++tdata->seen);
935 void test_bitmap_walk(struct rev_info *revs)
937 struct object *root;
938 struct bitmap *result = NULL;
939 khiter_t pos;
940 size_t result_popcnt;
941 struct bitmap_test_data tdata;
943 if (prepare_bitmap_git())
944 die("failed to load bitmap indexes");
946 if (revs->pending.nr != 1)
947 die("you must specify exactly one commit to test");
949 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
950 bitmap_git.version, bitmap_git.entry_count);
952 root = revs->pending.objects[0].item;
953 pos = kh_get_sha1(bitmap_git.bitmaps, root->sha1);
955 if (pos < kh_end(bitmap_git.bitmaps)) {
956 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
957 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
959 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
960 sha1_to_hex(root->sha1), (int)bm->bit_size, ewah_checksum(bm));
962 result = ewah_to_bitmap(bm);
965 if (result == NULL)
966 die("Commit %s doesn't have an indexed bitmap", sha1_to_hex(root->sha1));
968 revs->tag_objects = 1;
969 revs->tree_objects = 1;
970 revs->blob_objects = 1;
972 result_popcnt = bitmap_popcount(result);
974 if (prepare_revision_walk(revs))
975 die("revision walk setup failed");
977 tdata.base = bitmap_new();
978 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
979 tdata.seen = 0;
981 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
983 stop_progress(&tdata.prg);
985 if (bitmap_equals(result, tdata.base))
986 fprintf(stderr, "OK!\n");
987 else
988 fprintf(stderr, "Mismatch!\n");
991 static int rebuild_bitmap(uint32_t *reposition,
992 struct ewah_bitmap *source,
993 struct bitmap *dest)
995 uint32_t pos = 0;
996 struct ewah_iterator it;
997 eword_t word;
999 ewah_iterator_init(&it, source);
1001 while (ewah_iterator_next(&word, &it)) {
1002 uint32_t offset, bit_pos;
1004 for (offset = 0; offset < BITS_IN_WORD; ++offset) {
1005 if ((word >> offset) == 0)
1006 break;
1008 offset += ewah_bit_ctz64(word >> offset);
1010 bit_pos = reposition[pos + offset];
1011 if (bit_pos > 0)
1012 bitmap_set(dest, bit_pos - 1);
1013 else /* can't reuse, we don't have the object */
1014 return -1;
1017 pos += BITS_IN_WORD;
1019 return 0;
1022 int rebuild_existing_bitmaps(struct packing_data *mapping,
1023 khash_sha1 *reused_bitmaps,
1024 int show_progress)
1026 uint32_t i, num_objects;
1027 uint32_t *reposition;
1028 struct bitmap *rebuild;
1029 struct stored_bitmap *stored;
1030 struct progress *progress = NULL;
1032 khiter_t hash_pos;
1033 int hash_ret;
1035 if (prepare_bitmap_git() < 0)
1036 return -1;
1038 num_objects = bitmap_git.pack->num_objects;
1039 reposition = xcalloc(num_objects, sizeof(uint32_t));
1041 for (i = 0; i < num_objects; ++i) {
1042 const unsigned char *sha1;
1043 struct revindex_entry *entry;
1044 struct object_entry *oe;
1046 entry = &bitmap_git.reverse_index->revindex[i];
1047 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1048 oe = packlist_find(mapping, sha1, NULL);
1050 if (oe)
1051 reposition[i] = oe->in_pack_pos + 1;
1054 rebuild = bitmap_new();
1055 i = 0;
1057 if (show_progress)
1058 progress = start_progress("Reusing bitmaps", 0);
1060 kh_foreach_value(bitmap_git.bitmaps, stored, {
1061 if (stored->flags & BITMAP_FLAG_REUSE) {
1062 if (!rebuild_bitmap(reposition,
1063 lookup_stored_bitmap(stored),
1064 rebuild)) {
1065 hash_pos = kh_put_sha1(reused_bitmaps,
1066 stored->sha1,
1067 &hash_ret);
1068 kh_value(reused_bitmaps, hash_pos) =
1069 bitmap_to_ewah(rebuild);
1071 bitmap_reset(rebuild);
1072 display_progress(progress, ++i);
1076 stop_progress(&progress);
1078 free(reposition);
1079 bitmap_free(rebuild);
1080 return 0;