Convert struct object to object_id
[git/git.git] / pack-bitmap.c
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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 */
17struct 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 */
32static struct bitmap_index {
33 /* Packfile to which this bitmap index belongs to */
34 struct packed_git *pack;
35
36 /* reverse index for the packfile */
37 struct pack_revindex *reverse_index;
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
25143a54 63 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped commits */
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64 khash_sha1 *bitmaps;
65
66 /* Number of bitmapped commits */
67 uint32_t entry_count;
68
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69 /* Name-hash cache (or NULL if not present). */
70 uint32_t *hashes;
71
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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
96static 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 */
119static 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
137static 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)");
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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 }
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163 }
164
165 index->entry_count = ntohl(header->entry_count);
166 index->map_pos += sizeof(*header);
167 return 0;
168}
169
170static 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
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200static 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
207static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
208{
209 return buffer[(*pos)++];
210}
211
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212#define MAX_XOR_OFFSET 160
213
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214static int load_bitmap_entries_v1(struct bitmap_index *index)
215{
fff42755 216 uint32_t i;
599dc766 217 struct stored_bitmap *recent_bitmaps[MAX_XOR_OFFSET] = { NULL };
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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
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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);
fff42755 229
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230 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
231
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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
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253static char *pack_bitmap_filename(struct packed_git *p)
254{
9ae97018 255 size_t len;
cb468050 256
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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);
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260}
261
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262static 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_noatime(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
305static 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 bitmap_git.reverse_index = revindex_for_pack(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
325failed:
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
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332static 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 = packed_git; p; p = p->next) {
341 if (open_pack_bitmap_1(p) == 0)
342 ret = 0;
343 }
344
345 return ret;
346}
347
348int 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
359struct include_data {
360 struct bitmap *base;
361 struct bitmap *seen;
362};
363
364static 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
377static 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.reverse_index, offset);
384}
385
386static 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
392static 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
7999b2cf 400 hash_pos = kh_put_sha1_pos(eindex->positions, get_object_hash(*object), &hash_ret);
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401 if (hash_ret > 0) {
402 if (eindex->count >= eindex->alloc) {
403 eindex->alloc = (eindex->alloc + 16) * 3 / 2;
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404 REALLOC_ARRAY(eindex->objects, eindex->alloc);
405 REALLOC_ARRAY(eindex->hashes, eindex->alloc);
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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
420static void show_object(struct object *object, const struct name_path *path,
421 const char *last, void *data)
422{
423 struct bitmap *base = data;
424 int bitmap_pos;
425
7999b2cf 426 bitmap_pos = bitmap_position(get_object_hash(*object));
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427
428 if (bitmap_pos < 0) {
429 char *name = path_name(path, last);
430 bitmap_pos = ext_index_add_object(object, name);
431 free(name);
432 }
433
434 bitmap_set(base, bitmap_pos);
435}
436
437static void show_commit(struct commit *commit, void *data)
438{
439}
440
441static int add_to_include_set(struct include_data *data,
442 const unsigned char *sha1,
443 int bitmap_pos)
444{
445 khiter_t hash_pos;
446
447 if (data->seen && bitmap_get(data->seen, bitmap_pos))
448 return 0;
449
450 if (bitmap_get(data->base, bitmap_pos))
451 return 0;
452
453 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
454 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
455 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
456 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
457 return 0;
458 }
459
460 bitmap_set(data->base, bitmap_pos);
461 return 1;
462}
463
464static int should_include(struct commit *commit, void *_data)
465{
466 struct include_data *data = _data;
467 int bitmap_pos;
468
7999b2cf 469 bitmap_pos = bitmap_position(get_object_hash(commit->object));
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470 if (bitmap_pos < 0)
471 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
472
7999b2cf 473 if (!add_to_include_set(data, get_object_hash(commit->object), bitmap_pos)) {
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474 struct commit_list *parent = commit->parents;
475
476 while (parent) {
477 parent->item->object.flags |= SEEN;
478 parent = parent->next;
479 }
480
481 return 0;
482 }
483
484 return 1;
485}
486
487static struct bitmap *find_objects(struct rev_info *revs,
488 struct object_list *roots,
489 struct bitmap *seen)
490{
491 struct bitmap *base = NULL;
492 int needs_walk = 0;
493
494 struct object_list *not_mapped = NULL;
495
496 /*
497 * Go through all the roots for the walk. The ones that have bitmaps
498 * on the bitmap index will be `or`ed together to form an initial
499 * global reachability analysis.
500 *
501 * The ones without bitmaps in the index will be stored in the
502 * `not_mapped_list` for further processing.
503 */
504 while (roots) {
505 struct object *object = roots->item;
506 roots = roots->next;
507
508 if (object->type == OBJ_COMMIT) {
7999b2cf 509 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, get_object_hash(*object));
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510
511 if (pos < kh_end(bitmap_git.bitmaps)) {
512 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
513 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
514
515 if (base == NULL)
516 base = ewah_to_bitmap(or_with);
517 else
518 bitmap_or_ewah(base, or_with);
519
520 object->flags |= SEEN;
521 continue;
522 }
523 }
524
525 object_list_insert(object, &not_mapped);
526 }
527
528 /*
529 * Best case scenario: We found bitmaps for all the roots,
530 * so the resulting `or` bitmap has the full reachability analysis
531 */
532 if (not_mapped == NULL)
533 return base;
534
535 roots = not_mapped;
536
537 /*
538 * Let's iterate through all the roots that don't have bitmaps to
539 * check if we can determine them to be reachable from the existing
540 * global bitmap.
541 *
542 * If we cannot find them in the existing global bitmap, we'll need
543 * to push them to an actual walk and run it until we can confirm
544 * they are reachable
545 */
546 while (roots) {
547 struct object *object = roots->item;
548 int pos;
549
550 roots = roots->next;
7999b2cf 551 pos = bitmap_position(get_object_hash(*object));
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552
553 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
554 object->flags &= ~UNINTERESTING;
555 add_pending_object(revs, object, "");
556 needs_walk = 1;
557 } else {
558 object->flags |= SEEN;
559 }
560 }
561
562 if (needs_walk) {
563 struct include_data incdata;
564
565 if (base == NULL)
566 base = bitmap_new();
567
568 incdata.base = base;
569 incdata.seen = seen;
570
571 revs->include_check = should_include;
572 revs->include_check_data = &incdata;
573
574 if (prepare_revision_walk(revs))
575 die("revision walk setup failed");
576
577 traverse_commit_list(revs, show_commit, show_object, base);
578 }
579
580 return base;
581}
582
583static void show_extended_objects(struct bitmap *objects,
584 show_reachable_fn show_reach)
585{
586 struct eindex *eindex = &bitmap_git.ext_index;
587 uint32_t i;
588
589 for (i = 0; i < eindex->count; ++i) {
590 struct object *obj;
591
592 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
593 continue;
594
595 obj = eindex->objects[i];
7999b2cf 596 show_reach(get_object_hash(*obj), obj->type, 0, eindex->hashes[i], NULL, 0);
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597 }
598}
599
600static void show_objects_for_type(
601 struct bitmap *objects,
602 struct ewah_bitmap *type_filter,
603 enum object_type object_type,
604 show_reachable_fn show_reach)
605{
606 size_t pos = 0, i = 0;
607 uint32_t offset;
608
609 struct ewah_iterator it;
610 eword_t filter;
611
612 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
613 return;
614
615 ewah_iterator_init(&it, type_filter);
616
617 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
618 eword_t word = objects->words[i] & filter;
619
34b935c0 620 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
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621 const unsigned char *sha1;
622 struct revindex_entry *entry;
623 uint32_t hash = 0;
624
625 if ((word >> offset) == 0)
626 break;
627
628 offset += ewah_bit_ctz64(word >> offset);
629
630 if (pos + offset < bitmap_git.reuse_objects)
631 continue;
632
633 entry = &bitmap_git.reverse_index->revindex[pos + offset];
634 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
635
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636 if (bitmap_git.hashes)
637 hash = ntohl(bitmap_git.hashes[entry->nr]);
638
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639 show_reach(sha1, object_type, 0, hash, bitmap_git.pack, entry->offset);
640 }
641
34b935c0 642 pos += BITS_IN_EWORD;
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643 i++;
644 }
645}
646
647static int in_bitmapped_pack(struct object_list *roots)
648{
649 while (roots) {
650 struct object *object = roots->item;
651 roots = roots->next;
652
7999b2cf 653 if (find_pack_entry_one(get_object_hash(*object), bitmap_git.pack) > 0)
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654 return 1;
655 }
656
657 return 0;
658}
659
660int prepare_bitmap_walk(struct rev_info *revs)
661{
662 unsigned int i;
663 unsigned int pending_nr = revs->pending.nr;
664 struct object_array_entry *pending_e = revs->pending.objects;
665
666 struct object_list *wants = NULL;
667 struct object_list *haves = NULL;
668
669 struct bitmap *wants_bitmap = NULL;
670 struct bitmap *haves_bitmap = NULL;
671
672 if (!bitmap_git.loaded) {
673 /* try to open a bitmapped pack, but don't parse it yet
674 * because we may not need to use it */
675 if (open_pack_bitmap() < 0)
676 return -1;
677 }
678
679 for (i = 0; i < pending_nr; ++i) {
680 struct object *object = pending_e[i].item;
681
682 if (object->type == OBJ_NONE)
7999b2cf 683 parse_object_or_die(get_object_hash(*object), NULL);
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684
685 while (object->type == OBJ_TAG) {
686 struct tag *tag = (struct tag *) object;
687
688 if (object->flags & UNINTERESTING)
689 object_list_insert(object, &haves);
690 else
691 object_list_insert(object, &wants);
692
693 if (!tag->tagged)
694 die("bad tag");
7999b2cf 695 object = parse_object_or_die(get_object_hash(*tag->tagged), NULL);
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696 }
697
698 if (object->flags & UNINTERESTING)
699 object_list_insert(object, &haves);
700 else
701 object_list_insert(object, &wants);
702 }
703
704 /*
705 * if we have a HAVES list, but none of those haves is contained
706 * in the packfile that has a bitmap, we don't have anything to
707 * optimize here
708 */
709 if (haves && !in_bitmapped_pack(haves))
710 return -1;
711
712 /* if we don't want anything, we're done here */
713 if (!wants)
714 return -1;
715
716 /*
717 * now we're going to use bitmaps, so load the actual bitmap entries
718 * from disk. this is the point of no return; after this the rev_list
719 * becomes invalidated and we must perform the revwalk through bitmaps
720 */
721 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
722 return -1;
723
724 revs->pending.nr = 0;
725 revs->pending.alloc = 0;
726 revs->pending.objects = NULL;
727
728 if (haves) {
2db1a43f 729 revs->ignore_missing_links = 1;
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730 haves_bitmap = find_objects(revs, haves, NULL);
731 reset_revision_walk();
2db1a43f 732 revs->ignore_missing_links = 0;
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733
734 if (haves_bitmap == NULL)
735 die("BUG: failed to perform bitmap walk");
736 }
737
738 wants_bitmap = find_objects(revs, wants, haves_bitmap);
739
740 if (!wants_bitmap)
741 die("BUG: failed to perform bitmap walk");
742
743 if (haves_bitmap)
744 bitmap_and_not(wants_bitmap, haves_bitmap);
745
746 bitmap_git.result = wants_bitmap;
747
748 bitmap_free(haves_bitmap);
749 return 0;
750}
751
752int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
753 uint32_t *entries,
754 off_t *up_to)
755{
756 /*
757 * Reuse the packfile content if we need more than
758 * 90% of its objects
759 */
760 static const double REUSE_PERCENT = 0.9;
761
762 struct bitmap *result = bitmap_git.result;
763 uint32_t reuse_threshold;
764 uint32_t i, reuse_objects = 0;
765
766 assert(result);
767
768 for (i = 0; i < result->word_alloc; ++i) {
769 if (result->words[i] != (eword_t)~0) {
770 reuse_objects += ewah_bit_ctz64(~result->words[i]);
771 break;
772 }
773
34b935c0 774 reuse_objects += BITS_IN_EWORD;
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775 }
776
777#ifdef GIT_BITMAP_DEBUG
778 {
779 const unsigned char *sha1;
780 struct revindex_entry *entry;
781
782 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
783 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
784
785 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
786 reuse_objects, result->words[i]);
787 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
788 }
789#endif
790
791 if (!reuse_objects)
792 return -1;
793
794 if (reuse_objects >= bitmap_git.pack->num_objects) {
795 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
796 *up_to = -1; /* reuse the full pack */
797 *packfile = bitmap_git.pack;
798 return 0;
799 }
800
801 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
802
803 if (reuse_objects < reuse_threshold)
804 return -1;
805
806 bitmap_git.reuse_objects = *entries = reuse_objects;
807 *up_to = bitmap_git.reverse_index->revindex[reuse_objects].offset;
808 *packfile = bitmap_git.pack;
809
810 return 0;
811}
812
813void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
814{
815 assert(bitmap_git.result);
816
817 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
818 OBJ_COMMIT, show_reachable);
819 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
820 OBJ_TREE, show_reachable);
821 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
822 OBJ_BLOB, show_reachable);
823 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
824 OBJ_TAG, show_reachable);
825
826 show_extended_objects(bitmap_git.result, show_reachable);
827
828 bitmap_free(bitmap_git.result);
829 bitmap_git.result = NULL;
830}
831
832static uint32_t count_object_type(struct bitmap *objects,
833 enum object_type type)
834{
835 struct eindex *eindex = &bitmap_git.ext_index;
836
837 uint32_t i = 0, count = 0;
838 struct ewah_iterator it;
839 eword_t filter;
840
841 switch (type) {
842 case OBJ_COMMIT:
843 ewah_iterator_init(&it, bitmap_git.commits);
844 break;
845
846 case OBJ_TREE:
847 ewah_iterator_init(&it, bitmap_git.trees);
848 break;
849
850 case OBJ_BLOB:
851 ewah_iterator_init(&it, bitmap_git.blobs);
852 break;
853
854 case OBJ_TAG:
855 ewah_iterator_init(&it, bitmap_git.tags);
856 break;
857
858 default:
859 return 0;
860 }
861
862 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
863 eword_t word = objects->words[i++] & filter;
864 count += ewah_bit_popcount64(word);
865 }
866
867 for (i = 0; i < eindex->count; ++i) {
868 if (eindex->objects[i]->type == type &&
869 bitmap_get(objects, bitmap_git.pack->num_objects + i))
870 count++;
871 }
872
873 return count;
874}
875
876void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
877 uint32_t *blobs, uint32_t *tags)
878{
879 assert(bitmap_git.result);
880
881 if (commits)
882 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
883
884 if (trees)
885 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
886
887 if (blobs)
888 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
889
890 if (tags)
891 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
892}
893
894struct bitmap_test_data {
895 struct bitmap *base;
896 struct progress *prg;
897 size_t seen;
898};
899
900static void test_show_object(struct object *object,
901 const struct name_path *path,
902 const char *last, void *data)
903{
904 struct bitmap_test_data *tdata = data;
905 int bitmap_pos;
906
7999b2cf 907 bitmap_pos = bitmap_position(get_object_hash(*object));
fff42755 908 if (bitmap_pos < 0)
f2fd0760 909 die("Object not in bitmap: %s\n", oid_to_hex(&object->oid));
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910
911 bitmap_set(tdata->base, bitmap_pos);
912 display_progress(tdata->prg, ++tdata->seen);
913}
914
915static void test_show_commit(struct commit *commit, void *data)
916{
917 struct bitmap_test_data *tdata = data;
918 int bitmap_pos;
919
7999b2cf 920 bitmap_pos = bitmap_position(get_object_hash(commit->object));
fff42755 921 if (bitmap_pos < 0)
f2fd0760 922 die("Object not in bitmap: %s\n", oid_to_hex(&commit->object.oid));
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923
924 bitmap_set(tdata->base, bitmap_pos);
925 display_progress(tdata->prg, ++tdata->seen);
926}
927
928void test_bitmap_walk(struct rev_info *revs)
929{
930 struct object *root;
931 struct bitmap *result = NULL;
932 khiter_t pos;
933 size_t result_popcnt;
934 struct bitmap_test_data tdata;
935
936 if (prepare_bitmap_git())
937 die("failed to load bitmap indexes");
938
939 if (revs->pending.nr != 1)
940 die("you must specify exactly one commit to test");
941
942 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
943 bitmap_git.version, bitmap_git.entry_count);
944
945 root = revs->pending.objects[0].item;
7999b2cf 946 pos = kh_get_sha1(bitmap_git.bitmaps, get_object_hash(*root));
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947
948 if (pos < kh_end(bitmap_git.bitmaps)) {
949 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
950 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
951
952 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
f2fd0760 953 oid_to_hex(&root->oid), (int)bm->bit_size, ewah_checksum(bm));
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954
955 result = ewah_to_bitmap(bm);
956 }
957
958 if (result == NULL)
f2fd0760 959 die("Commit %s doesn't have an indexed bitmap", oid_to_hex(&root->oid));
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960
961 revs->tag_objects = 1;
962 revs->tree_objects = 1;
963 revs->blob_objects = 1;
964
965 result_popcnt = bitmap_popcount(result);
966
967 if (prepare_revision_walk(revs))
968 die("revision walk setup failed");
969
970 tdata.base = bitmap_new();
971 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
972 tdata.seen = 0;
973
974 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
975
976 stop_progress(&tdata.prg);
977
978 if (bitmap_equals(result, tdata.base))
979 fprintf(stderr, "OK!\n");
980 else
981 fprintf(stderr, "Mismatch!\n");
f86a3747 982
d201a1ec 983 bitmap_free(result);
fff42755 984}
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985
986static int rebuild_bitmap(uint32_t *reposition,
987 struct ewah_bitmap *source,
988 struct bitmap *dest)
989{
990 uint32_t pos = 0;
991 struct ewah_iterator it;
992 eword_t word;
993
994 ewah_iterator_init(&it, source);
995
996 while (ewah_iterator_next(&word, &it)) {
997 uint32_t offset, bit_pos;
998
34b935c0 999 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
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1000 if ((word >> offset) == 0)
1001 break;
1002
1003 offset += ewah_bit_ctz64(word >> offset);
1004
1005 bit_pos = reposition[pos + offset];
1006 if (bit_pos > 0)
1007 bitmap_set(dest, bit_pos - 1);
1008 else /* can't reuse, we don't have the object */
1009 return -1;
1010 }
1011
34b935c0 1012 pos += BITS_IN_EWORD;
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1013 }
1014 return 0;
1015}
1016
1017int rebuild_existing_bitmaps(struct packing_data *mapping,
1018 khash_sha1 *reused_bitmaps,
1019 int show_progress)
1020{
1021 uint32_t i, num_objects;
1022 uint32_t *reposition;
1023 struct bitmap *rebuild;
1024 struct stored_bitmap *stored;
1025 struct progress *progress = NULL;
1026
1027 khiter_t hash_pos;
1028 int hash_ret;
1029
1030 if (prepare_bitmap_git() < 0)
1031 return -1;
1032
1033 num_objects = bitmap_git.pack->num_objects;
1034 reposition = xcalloc(num_objects, sizeof(uint32_t));
1035
1036 for (i = 0; i < num_objects; ++i) {
1037 const unsigned char *sha1;
1038 struct revindex_entry *entry;
1039 struct object_entry *oe;
1040
1041 entry = &bitmap_git.reverse_index->revindex[i];
1042 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1043 oe = packlist_find(mapping, sha1, NULL);
1044
1045 if (oe)
1046 reposition[i] = oe->in_pack_pos + 1;
1047 }
1048
1049 rebuild = bitmap_new();
1050 i = 0;
1051
1052 if (show_progress)
1053 progress = start_progress("Reusing bitmaps", 0);
1054
1055 kh_foreach_value(bitmap_git.bitmaps, stored, {
1056 if (stored->flags & BITMAP_FLAG_REUSE) {
1057 if (!rebuild_bitmap(reposition,
1058 lookup_stored_bitmap(stored),
1059 rebuild)) {
1060 hash_pos = kh_put_sha1(reused_bitmaps,
1061 stored->sha1,
1062 &hash_ret);
1063 kh_value(reused_bitmaps, hash_pos) =
1064 bitmap_to_ewah(rebuild);
1065 }
1066 bitmap_reset(rebuild);
1067 display_progress(progress, ++i);
1068 }
1069 });
1070
1071 stop_progress(&progress);
1072
1073 free(reposition);
1074 bitmap_free(rebuild);
1075 return 0;
1076}