The seventh batch
[git/git.git] / midx.c
CommitLineData
a3407730 1#include "cache.h"
c4d25228 2#include "config.h"
fc59e748 3#include "csum-file.h"
396f2570 4#include "dir.h"
fc59e748 5#include "lockfile.h"
396f2570 6#include "packfile.h"
4d80560c 7#include "object-store.h"
3715a633 8#include "sha1-lookup.h"
a3407730 9#include "midx.h"
144d7033 10#include "progress.h"
d829223a 11#include "trace2.h"
a3407730 12
fc59e748
DS
13#define MIDX_SIGNATURE 0x4d494458 /* "MIDX" */
14#define MIDX_VERSION 1
4d80560c
DS
15#define MIDX_BYTE_FILE_VERSION 4
16#define MIDX_BYTE_HASH_VERSION 5
17#define MIDX_BYTE_NUM_CHUNKS 6
18#define MIDX_BYTE_NUM_PACKS 8
fc59e748
DS
19#define MIDX_HASH_VERSION 1
20#define MIDX_HEADER_SIZE 12
4d80560c
DS
21#define MIDX_HASH_LEN 20
22#define MIDX_MIN_SIZE (MIDX_HEADER_SIZE + MIDX_HASH_LEN)
fc59e748 23
662148c4 24#define MIDX_MAX_CHUNKS 5
32f3c541
DS
25#define MIDX_CHUNK_ALIGNMENT 4
26#define MIDX_CHUNKID_PACKNAMES 0x504e414d /* "PNAM" */
d7cacf29 27#define MIDX_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
0d5b3a5e 28#define MIDX_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
662148c4
DS
29#define MIDX_CHUNKID_OBJECTOFFSETS 0x4f4f4646 /* "OOFF" */
30#define MIDX_CHUNKID_LARGEOFFSETS 0x4c4f4646 /* "LOFF" */
32f3c541 31#define MIDX_CHUNKLOOKUP_WIDTH (sizeof(uint32_t) + sizeof(uint64_t))
d7cacf29 32#define MIDX_CHUNK_FANOUT_SIZE (sizeof(uint32_t) * 256)
662148c4
DS
33#define MIDX_CHUNK_OFFSET_WIDTH (2 * sizeof(uint32_t))
34#define MIDX_CHUNK_LARGE_OFFSET_WIDTH (sizeof(uint64_t))
35#define MIDX_LARGE_OFFSET_NEEDED 0x80000000
32f3c541 36
fc59e748
DS
37static char *get_midx_filename(const char *object_dir)
38{
39 return xstrfmt("%s/pack/multi-pack-index", object_dir);
40}
41
2cf489a3 42struct multi_pack_index *load_multi_pack_index(const char *object_dir, int local)
4d80560c
DS
43{
44 struct multi_pack_index *m = NULL;
45 int fd;
46 struct stat st;
47 size_t midx_size;
48 void *midx_map = NULL;
49 uint32_t hash_version;
50 char *midx_name = get_midx_filename(object_dir);
32f3c541 51 uint32_t i;
3227565c 52 const char *cur_pack_name;
4d80560c
DS
53
54 fd = git_open(midx_name);
55
56 if (fd < 0)
57 goto cleanup_fail;
58 if (fstat(fd, &st)) {
59 error_errno(_("failed to read %s"), midx_name);
60 goto cleanup_fail;
61 }
62
63 midx_size = xsize_t(st.st_size);
64
65 if (midx_size < MIDX_MIN_SIZE) {
66 error(_("multi-pack-index file %s is too small"), midx_name);
67 goto cleanup_fail;
68 }
69
70 FREE_AND_NULL(midx_name);
71
72 midx_map = xmmap(NULL, midx_size, PROT_READ, MAP_PRIVATE, fd, 0);
73
577314ca 74 FLEX_ALLOC_STR(m, object_dir, object_dir);
4d80560c
DS
75 m->fd = fd;
76 m->data = midx_map;
77 m->data_len = midx_size;
2cf489a3 78 m->local = local;
4d80560c
DS
79
80 m->signature = get_be32(m->data);
53ad0407
DS
81 if (m->signature != MIDX_SIGNATURE)
82 die(_("multi-pack-index signature 0x%08x does not match signature 0x%08x"),
4d80560c 83 m->signature, MIDX_SIGNATURE);
4d80560c
DS
84
85 m->version = m->data[MIDX_BYTE_FILE_VERSION];
53ad0407
DS
86 if (m->version != MIDX_VERSION)
87 die(_("multi-pack-index version %d not recognized"),
4d80560c 88 m->version);
4d80560c
DS
89
90 hash_version = m->data[MIDX_BYTE_HASH_VERSION];
53ad0407
DS
91 if (hash_version != MIDX_HASH_VERSION)
92 die(_("hash version %u does not match"), hash_version);
4d80560c
DS
93 m->hash_len = MIDX_HASH_LEN;
94
95 m->num_chunks = m->data[MIDX_BYTE_NUM_CHUNKS];
96
97 m->num_packs = get_be32(m->data + MIDX_BYTE_NUM_PACKS);
98
32f3c541
DS
99 for (i = 0; i < m->num_chunks; i++) {
100 uint32_t chunk_id = get_be32(m->data + MIDX_HEADER_SIZE +
101 MIDX_CHUNKLOOKUP_WIDTH * i);
102 uint64_t chunk_offset = get_be64(m->data + MIDX_HEADER_SIZE + 4 +
103 MIDX_CHUNKLOOKUP_WIDTH * i);
104
d3f8e211
DS
105 if (chunk_offset >= m->data_len)
106 die(_("invalid chunk offset (too large)"));
107
32f3c541
DS
108 switch (chunk_id) {
109 case MIDX_CHUNKID_PACKNAMES:
110 m->chunk_pack_names = m->data + chunk_offset;
111 break;
112
d7cacf29
DS
113 case MIDX_CHUNKID_OIDFANOUT:
114 m->chunk_oid_fanout = (uint32_t *)(m->data + chunk_offset);
115 break;
116
0d5b3a5e
DS
117 case MIDX_CHUNKID_OIDLOOKUP:
118 m->chunk_oid_lookup = m->data + chunk_offset;
119 break;
120
662148c4
DS
121 case MIDX_CHUNKID_OBJECTOFFSETS:
122 m->chunk_object_offsets = m->data + chunk_offset;
123 break;
124
125 case MIDX_CHUNKID_LARGEOFFSETS:
126 m->chunk_large_offsets = m->data + chunk_offset;
127 break;
128
32f3c541
DS
129 case 0:
130 die(_("terminating multi-pack-index chunk id appears earlier than expected"));
131 break;
132
133 default:
134 /*
135 * Do nothing on unrecognized chunks, allowing future
136 * extensions to add optional chunks.
137 */
138 break;
139 }
140 }
141
142 if (!m->chunk_pack_names)
143 die(_("multi-pack-index missing required pack-name chunk"));
d7cacf29
DS
144 if (!m->chunk_oid_fanout)
145 die(_("multi-pack-index missing required OID fanout chunk"));
0d5b3a5e
DS
146 if (!m->chunk_oid_lookup)
147 die(_("multi-pack-index missing required OID lookup chunk"));
662148c4
DS
148 if (!m->chunk_object_offsets)
149 die(_("multi-pack-index missing required object offsets chunk"));
32f3c541 150
d7cacf29
DS
151 m->num_objects = ntohl(m->chunk_oid_fanout[255]);
152
3227565c 153 m->pack_names = xcalloc(m->num_packs, sizeof(*m->pack_names));
3715a633 154 m->packs = xcalloc(m->num_packs, sizeof(*m->packs));
3227565c
DS
155
156 cur_pack_name = (const char *)m->chunk_pack_names;
157 for (i = 0; i < m->num_packs; i++) {
158 m->pack_names[i] = cur_pack_name;
159
160 cur_pack_name += strlen(cur_pack_name) + 1;
161
8e72a3c3
DS
162 if (i && strcmp(m->pack_names[i], m->pack_names[i - 1]) <= 0)
163 die(_("multi-pack-index pack names out of order: '%s' before '%s'"),
3227565c
DS
164 m->pack_names[i - 1],
165 m->pack_names[i]);
3227565c
DS
166 }
167
d829223a
JH
168 trace2_data_intmax("midx", the_repository, "load/num_packs", m->num_packs);
169 trace2_data_intmax("midx", the_repository, "load/num_objects", m->num_objects);
170
4d80560c
DS
171 return m;
172
173cleanup_fail:
174 free(m);
175 free(midx_name);
176 if (midx_map)
177 munmap(midx_map, midx_size);
178 if (0 <= fd)
179 close(fd);
180 return NULL;
181}
182
1dcd9f20 183void close_midx(struct multi_pack_index *m)
a40498a1
DS
184{
185 uint32_t i;
1dcd9f20
DS
186
187 if (!m)
188 return;
189
a40498a1
DS
190 munmap((unsigned char *)m->data, m->data_len);
191 close(m->fd);
192 m->fd = -1;
193
194 for (i = 0; i < m->num_packs; i++) {
195 if (m->packs[i]) {
196 close_pack(m->packs[i]);
0ce4ff94 197 free(m->packs[i]);
a40498a1
DS
198 }
199 }
200 FREE_AND_NULL(m->packs);
201 FREE_AND_NULL(m->pack_names);
202}
203
0bff5269 204int prepare_midx_pack(struct multi_pack_index *m, uint32_t pack_int_id)
3715a633
DS
205{
206 struct strbuf pack_name = STRBUF_INIT;
207
208 if (pack_int_id >= m->num_packs)
d355e46a 209 die(_("bad pack-int-id: %u (%u total packs)"),
cc6af73c 210 pack_int_id, m->num_packs);
3715a633
DS
211
212 if (m->packs[pack_int_id])
213 return 0;
214
215 strbuf_addf(&pack_name, "%s/pack/%s", m->object_dir,
216 m->pack_names[pack_int_id]);
217
2cf489a3 218 m->packs[pack_int_id] = add_packed_git(pack_name.buf, pack_name.len, m->local);
3715a633
DS
219 strbuf_release(&pack_name);
220 return !m->packs[pack_int_id];
221}
222
223int bsearch_midx(const struct object_id *oid, struct multi_pack_index *m, uint32_t *result)
224{
225 return bsearch_hash(oid->hash, m->chunk_oid_fanout, m->chunk_oid_lookup,
226 MIDX_HASH_LEN, result);
227}
228
8aac67a1
DS
229struct object_id *nth_midxed_object_oid(struct object_id *oid,
230 struct multi_pack_index *m,
231 uint32_t n)
232{
233 if (n >= m->num_objects)
234 return NULL;
235
236 hashcpy(oid->hash, m->chunk_oid_lookup + m->hash_len * n);
237 return oid;
238}
239
3715a633
DS
240static off_t nth_midxed_offset(struct multi_pack_index *m, uint32_t pos)
241{
242 const unsigned char *offset_data;
243 uint32_t offset32;
244
245 offset_data = m->chunk_object_offsets + pos * MIDX_CHUNK_OFFSET_WIDTH;
246 offset32 = get_be32(offset_data + sizeof(uint32_t));
247
248 if (m->chunk_large_offsets && offset32 & MIDX_LARGE_OFFSET_NEEDED) {
d8ac9ee1 249 if (sizeof(off_t) < sizeof(uint64_t))
3715a633
DS
250 die(_("multi-pack-index stores a 64-bit offset, but off_t is too small"));
251
252 offset32 ^= MIDX_LARGE_OFFSET_NEEDED;
253 return get_be64(m->chunk_large_offsets + sizeof(uint64_t) * offset32);
254 }
255
256 return offset32;
257}
258
259static uint32_t nth_midxed_pack_int_id(struct multi_pack_index *m, uint32_t pos)
260{
261 return get_be32(m->chunk_object_offsets + pos * MIDX_CHUNK_OFFSET_WIDTH);
262}
263
264static int nth_midxed_pack_entry(struct multi_pack_index *m, struct pack_entry *e, uint32_t pos)
265{
266 uint32_t pack_int_id;
267 struct packed_git *p;
268
269 if (pos >= m->num_objects)
270 return 0;
271
272 pack_int_id = nth_midxed_pack_int_id(m, pos);
273
274 if (prepare_midx_pack(m, pack_int_id))
275 die(_("error preparing packfile from multi-pack-index"));
276 p = m->packs[pack_int_id];
277
278 /*
279 * We are about to tell the caller where they can locate the
280 * requested object. We better make sure the packfile is
281 * still here and can be accessed before supplying that
282 * answer, as it may have been deleted since the MIDX was
283 * loaded!
284 */
285 if (!is_pack_valid(p))
286 return 0;
287
c39b02ae
DS
288 if (p->num_bad_objects) {
289 uint32_t i;
290 struct object_id oid;
291 nth_midxed_object_oid(&oid, m, pos);
292 for (i = 0; i < p->num_bad_objects; i++)
e43d2dcc
JK
293 if (hasheq(oid.hash,
294 p->bad_object_sha1 + the_hash_algo->rawsz * i))
c39b02ae
DS
295 return 0;
296 }
297
3715a633
DS
298 e->offset = nth_midxed_offset(m, pos);
299 e->p = p;
300
301 return 1;
302}
303
304int fill_midx_entry(const struct object_id *oid, struct pack_entry *e, struct multi_pack_index *m)
305{
306 uint32_t pos;
307
308 if (!bsearch_midx(oid, m, &pos))
309 return 0;
310
311 return nth_midxed_pack_entry(m, e, pos);
312}
313
013fd7ad
JK
314/* Match "foo.idx" against either "foo.pack" _or_ "foo.idx". */
315static int cmp_idx_or_pack_name(const char *idx_or_pack_name,
316 const char *idx_name)
317{
318 /* Skip past any initial matching prefix. */
319 while (*idx_name && *idx_name == *idx_or_pack_name) {
320 idx_name++;
321 idx_or_pack_name++;
322 }
323
324 /*
325 * If we didn't match completely, we may have matched "pack-1234." and
326 * be left with "idx" and "pack" respectively, which is also OK. We do
327 * not have to check for "idx" and "idx", because that would have been
328 * a complete match (and in that case these strcmps will be false, but
329 * we'll correctly return 0 from the final strcmp() below.
330 *
331 * Technically this matches "fooidx" and "foopack", but we'd never have
332 * such names in the first place.
333 */
334 if (!strcmp(idx_name, "idx") && !strcmp(idx_or_pack_name, "pack"))
335 return 0;
336
337 /*
338 * This not only checks for a complete match, but also orders based on
339 * the first non-identical character, which means our ordering will
340 * match a raw strcmp(). That makes it OK to use this to binary search
341 * a naively-sorted list.
342 */
343 return strcmp(idx_or_pack_name, idx_name);
344}
345
346int midx_contains_pack(struct multi_pack_index *m, const char *idx_or_pack_name)
a40498a1
DS
347{
348 uint32_t first = 0, last = m->num_packs;
349
350 while (first < last) {
351 uint32_t mid = first + (last - first) / 2;
352 const char *current;
353 int cmp;
354
355 current = m->pack_names[mid];
013fd7ad 356 cmp = cmp_idx_or_pack_name(idx_or_pack_name, current);
a40498a1
DS
357 if (!cmp)
358 return 1;
359 if (cmp > 0) {
360 first = mid + 1;
361 continue;
362 }
363 last = mid;
364 }
365
366 return 0;
367}
368
2cf489a3 369int prepare_multi_pack_index_one(struct repository *r, const char *object_dir, int local)
c4d25228 370{
29e2016b 371 struct multi_pack_index *m;
c4d25228
DS
372 struct multi_pack_index *m_search;
373 int config_value;
0465a505 374 static int env_value = -1;
c4d25228 375
0465a505
DS
376 if (env_value < 0)
377 env_value = git_env_bool(GIT_TEST_MULTI_PACK_INDEX, 0);
c4d25228 378
0465a505
DS
379 if (!env_value &&
380 (repo_config_get_bool(r, "core.multipackindex", &config_value) ||
381 !config_value))
c4d25228
DS
382 return 0;
383
29e2016b 384 for (m_search = r->objects->multi_pack_index; m_search; m_search = m_search->next)
c4d25228
DS
385 if (!strcmp(object_dir, m_search->object_dir))
386 return 1;
387
29e2016b 388 m = load_multi_pack_index(object_dir, local);
c4d25228 389
29e2016b
DS
390 if (m) {
391 m->next = r->objects->multi_pack_index;
392 r->objects->multi_pack_index = m;
c4d25228
DS
393 return 1;
394 }
395
396 return 0;
397}
398
fc59e748
DS
399static size_t write_midx_header(struct hashfile *f,
400 unsigned char num_chunks,
401 uint32_t num_packs)
402{
403 unsigned char byte_values[4];
404
405 hashwrite_be32(f, MIDX_SIGNATURE);
406 byte_values[0] = MIDX_VERSION;
407 byte_values[1] = MIDX_HASH_VERSION;
408 byte_values[2] = num_chunks;
409 byte_values[3] = 0; /* unused */
410 hashwrite(f, byte_values, sizeof(byte_values));
411 hashwrite_be32(f, num_packs);
412
413 return MIDX_HEADER_SIZE;
414}
415
396f2570
DS
416struct pack_list {
417 struct packed_git **list;
32f3c541 418 char **names;
396f2570
DS
419 uint32_t nr;
420 uint32_t alloc_list;
32f3c541
DS
421 uint32_t alloc_names;
422 size_t pack_name_concat_len;
a40498a1 423 struct multi_pack_index *m;
396f2570
DS
424};
425
426static void add_pack_to_midx(const char *full_path, size_t full_path_len,
427 const char *file_name, void *data)
428{
429 struct pack_list *packs = (struct pack_list *)data;
430
431 if (ends_with(file_name, ".idx")) {
a40498a1
DS
432 if (packs->m && midx_contains_pack(packs->m, file_name))
433 return;
434
396f2570 435 ALLOC_GROW(packs->list, packs->nr + 1, packs->alloc_list);
32f3c541 436 ALLOC_GROW(packs->names, packs->nr + 1, packs->alloc_names);
396f2570
DS
437
438 packs->list[packs->nr] = add_packed_git(full_path,
439 full_path_len,
440 0);
fe1ed56f 441
396f2570
DS
442 if (!packs->list[packs->nr]) {
443 warning(_("failed to add packfile '%s'"),
444 full_path);
445 return;
446 }
447
fe1ed56f
DS
448 if (open_pack_index(packs->list[packs->nr])) {
449 warning(_("failed to open pack-index '%s'"),
450 full_path);
451 close_pack(packs->list[packs->nr]);
452 FREE_AND_NULL(packs->list[packs->nr]);
453 return;
454 }
455
32f3c541
DS
456 packs->names[packs->nr] = xstrdup(file_name);
457 packs->pack_name_concat_len += strlen(file_name) + 1;
396f2570
DS
458 packs->nr++;
459 }
460}
461
32f3c541
DS
462struct pack_pair {
463 uint32_t pack_int_id;
464 char *pack_name;
465};
466
467static int pack_pair_compare(const void *_a, const void *_b)
468{
469 struct pack_pair *a = (struct pack_pair *)_a;
470 struct pack_pair *b = (struct pack_pair *)_b;
471 return strcmp(a->pack_name, b->pack_name);
472}
473
474static void sort_packs_by_name(char **pack_names, uint32_t nr_packs, uint32_t *perm)
475{
476 uint32_t i;
477 struct pack_pair *pairs;
478
479 ALLOC_ARRAY(pairs, nr_packs);
480
481 for (i = 0; i < nr_packs; i++) {
482 pairs[i].pack_int_id = i;
483 pairs[i].pack_name = pack_names[i];
484 }
485
486 QSORT(pairs, nr_packs, pack_pair_compare);
487
488 for (i = 0; i < nr_packs; i++) {
489 pack_names[i] = pairs[i].pack_name;
490 perm[pairs[i].pack_int_id] = i;
491 }
492
493 free(pairs);
494}
495
fe1ed56f
DS
496struct pack_midx_entry {
497 struct object_id oid;
498 uint32_t pack_int_id;
499 time_t pack_mtime;
500 uint64_t offset;
501};
502
503static int midx_oid_compare(const void *_a, const void *_b)
504{
505 const struct pack_midx_entry *a = (const struct pack_midx_entry *)_a;
506 const struct pack_midx_entry *b = (const struct pack_midx_entry *)_b;
507 int cmp = oidcmp(&a->oid, &b->oid);
508
509 if (cmp)
510 return cmp;
511
512 if (a->pack_mtime > b->pack_mtime)
513 return -1;
514 else if (a->pack_mtime < b->pack_mtime)
515 return 1;
516
517 return a->pack_int_id - b->pack_int_id;
518}
519
a40498a1
DS
520static int nth_midxed_pack_midx_entry(struct multi_pack_index *m,
521 uint32_t *pack_perm,
522 struct pack_midx_entry *e,
523 uint32_t pos)
524{
525 if (pos >= m->num_objects)
526 return 1;
527
528 nth_midxed_object_oid(&e->oid, m, pos);
529 e->pack_int_id = pack_perm[nth_midxed_pack_int_id(m, pos)];
530 e->offset = nth_midxed_offset(m, pos);
531
532 /* consider objects in midx to be from "old" packs */
533 e->pack_mtime = 0;
534 return 0;
535}
536
fe1ed56f
DS
537static void fill_pack_entry(uint32_t pack_int_id,
538 struct packed_git *p,
539 uint32_t cur_object,
540 struct pack_midx_entry *entry)
541{
542 if (!nth_packed_object_oid(&entry->oid, p, cur_object))
543 die(_("failed to locate object %d in packfile"), cur_object);
544
545 entry->pack_int_id = pack_int_id;
546 entry->pack_mtime = p->mtime;
547
548 entry->offset = nth_packed_object_offset(p, cur_object);
549}
550
551/*
552 * It is possible to artificially get into a state where there are many
553 * duplicate copies of objects. That can create high memory pressure if
554 * we are to create a list of all objects before de-duplication. To reduce
555 * this memory pressure without a significant performance drop, automatically
556 * group objects by the first byte of their object id. Use the IDX fanout
557 * tables to group the data, copy to a local array, then sort.
558 *
559 * Copy only the de-duplicated entries (selected by most-recent modified time
560 * of a packfile containing the object).
561 */
a40498a1
DS
562static struct pack_midx_entry *get_sorted_entries(struct multi_pack_index *m,
563 struct packed_git **p,
fe1ed56f
DS
564 uint32_t *perm,
565 uint32_t nr_packs,
566 uint32_t *nr_objects)
567{
568 uint32_t cur_fanout, cur_pack, cur_object;
569 uint32_t alloc_fanout, alloc_objects, total_objects = 0;
570 struct pack_midx_entry *entries_by_fanout = NULL;
571 struct pack_midx_entry *deduplicated_entries = NULL;
a40498a1 572 uint32_t start_pack = m ? m->num_packs : 0;
fe1ed56f 573
a40498a1 574 for (cur_pack = start_pack; cur_pack < nr_packs; cur_pack++)
fe1ed56f
DS
575 total_objects += p[cur_pack]->num_objects;
576
577 /*
578 * As we de-duplicate by fanout value, we expect the fanout
579 * slices to be evenly distributed, with some noise. Hence,
580 * allocate slightly more than one 256th.
581 */
582 alloc_objects = alloc_fanout = total_objects > 3200 ? total_objects / 200 : 16;
583
584 ALLOC_ARRAY(entries_by_fanout, alloc_fanout);
585 ALLOC_ARRAY(deduplicated_entries, alloc_objects);
586 *nr_objects = 0;
587
588 for (cur_fanout = 0; cur_fanout < 256; cur_fanout++) {
589 uint32_t nr_fanout = 0;
590
a40498a1
DS
591 if (m) {
592 uint32_t start = 0, end;
593
594 if (cur_fanout)
595 start = ntohl(m->chunk_oid_fanout[cur_fanout - 1]);
596 end = ntohl(m->chunk_oid_fanout[cur_fanout]);
597
598 for (cur_object = start; cur_object < end; cur_object++) {
599 ALLOC_GROW(entries_by_fanout, nr_fanout + 1, alloc_fanout);
600 nth_midxed_pack_midx_entry(m, perm,
601 &entries_by_fanout[nr_fanout],
602 cur_object);
603 nr_fanout++;
604 }
605 }
606
607 for (cur_pack = start_pack; cur_pack < nr_packs; cur_pack++) {
fe1ed56f
DS
608 uint32_t start = 0, end;
609
610 if (cur_fanout)
611 start = get_pack_fanout(p[cur_pack], cur_fanout - 1);
612 end = get_pack_fanout(p[cur_pack], cur_fanout);
613
614 for (cur_object = start; cur_object < end; cur_object++) {
615 ALLOC_GROW(entries_by_fanout, nr_fanout + 1, alloc_fanout);
616 fill_pack_entry(perm[cur_pack], p[cur_pack], cur_object, &entries_by_fanout[nr_fanout]);
617 nr_fanout++;
618 }
619 }
620
621 QSORT(entries_by_fanout, nr_fanout, midx_oid_compare);
622
623 /*
624 * The batch is now sorted by OID and then mtime (descending).
625 * Take only the first duplicate.
626 */
627 for (cur_object = 0; cur_object < nr_fanout; cur_object++) {
e43d2dcc
JK
628 if (cur_object && oideq(&entries_by_fanout[cur_object - 1].oid,
629 &entries_by_fanout[cur_object].oid))
fe1ed56f
DS
630 continue;
631
632 ALLOC_GROW(deduplicated_entries, *nr_objects + 1, alloc_objects);
633 memcpy(&deduplicated_entries[*nr_objects],
634 &entries_by_fanout[cur_object],
635 sizeof(struct pack_midx_entry));
636 (*nr_objects)++;
637 }
638 }
639
640 free(entries_by_fanout);
641 return deduplicated_entries;
642}
643
32f3c541
DS
644static size_t write_midx_pack_names(struct hashfile *f,
645 char **pack_names,
646 uint32_t num_packs)
647{
648 uint32_t i;
649 unsigned char padding[MIDX_CHUNK_ALIGNMENT];
650 size_t written = 0;
651
652 for (i = 0; i < num_packs; i++) {
653 size_t writelen = strlen(pack_names[i]) + 1;
654
655 if (i && strcmp(pack_names[i], pack_names[i - 1]) <= 0)
656 BUG("incorrect pack-file order: %s before %s",
657 pack_names[i - 1],
658 pack_names[i]);
659
660 hashwrite(f, pack_names[i], writelen);
661 written += writelen;
662 }
663
664 /* add padding to be aligned */
665 i = MIDX_CHUNK_ALIGNMENT - (written % MIDX_CHUNK_ALIGNMENT);
666 if (i < MIDX_CHUNK_ALIGNMENT) {
667 memset(padding, 0, sizeof(padding));
668 hashwrite(f, padding, i);
669 written += i;
670 }
671
672 return written;
673}
674
d7cacf29
DS
675static size_t write_midx_oid_fanout(struct hashfile *f,
676 struct pack_midx_entry *objects,
677 uint32_t nr_objects)
678{
679 struct pack_midx_entry *list = objects;
680 struct pack_midx_entry *last = objects + nr_objects;
681 uint32_t count = 0;
682 uint32_t i;
683
684 /*
685 * Write the first-level table (the list is sorted,
686 * but we use a 256-entry lookup to be able to avoid
687 * having to do eight extra binary search iterations).
688 */
689 for (i = 0; i < 256; i++) {
690 struct pack_midx_entry *next = list;
691
692 while (next < last && next->oid.hash[0] == i) {
693 count++;
694 next++;
695 }
696
697 hashwrite_be32(f, count);
698 list = next;
699 }
700
701 return MIDX_CHUNK_FANOUT_SIZE;
702}
703
0d5b3a5e
DS
704static size_t write_midx_oid_lookup(struct hashfile *f, unsigned char hash_len,
705 struct pack_midx_entry *objects,
706 uint32_t nr_objects)
707{
708 struct pack_midx_entry *list = objects;
709 uint32_t i;
710 size_t written = 0;
711
712 for (i = 0; i < nr_objects; i++) {
713 struct pack_midx_entry *obj = list++;
714
715 if (i < nr_objects - 1) {
716 struct pack_midx_entry *next = list;
717 if (oidcmp(&obj->oid, &next->oid) >= 0)
718 BUG("OIDs not in order: %s >= %s",
719 oid_to_hex(&obj->oid),
720 oid_to_hex(&next->oid));
721 }
722
723 hashwrite(f, obj->oid.hash, (int)hash_len);
724 written += hash_len;
725 }
726
727 return written;
728}
729
662148c4
DS
730static size_t write_midx_object_offsets(struct hashfile *f, int large_offset_needed,
731 struct pack_midx_entry *objects, uint32_t nr_objects)
732{
733 struct pack_midx_entry *list = objects;
734 uint32_t i, nr_large_offset = 0;
735 size_t written = 0;
736
737 for (i = 0; i < nr_objects; i++) {
738 struct pack_midx_entry *obj = list++;
739
740 hashwrite_be32(f, obj->pack_int_id);
741
742 if (large_offset_needed && obj->offset >> 31)
743 hashwrite_be32(f, MIDX_LARGE_OFFSET_NEEDED | nr_large_offset++);
744 else if (!large_offset_needed && obj->offset >> 32)
745 BUG("object %s requires a large offset (%"PRIx64") but the MIDX is not writing large offsets!",
746 oid_to_hex(&obj->oid),
747 obj->offset);
748 else
749 hashwrite_be32(f, (uint32_t)obj->offset);
750
751 written += MIDX_CHUNK_OFFSET_WIDTH;
752 }
753
754 return written;
755}
756
757static size_t write_midx_large_offsets(struct hashfile *f, uint32_t nr_large_offset,
758 struct pack_midx_entry *objects, uint32_t nr_objects)
759{
61b0fcbb 760 struct pack_midx_entry *list = objects, *end = objects + nr_objects;
662148c4
DS
761 size_t written = 0;
762
763 while (nr_large_offset) {
61b0fcbb
JK
764 struct pack_midx_entry *obj;
765 uint64_t offset;
766
767 if (list >= end)
768 BUG("too many large-offset objects");
769
770 obj = list++;
771 offset = obj->offset;
662148c4
DS
772
773 if (!(offset >> 31))
774 continue;
775
776 hashwrite_be32(f, offset >> 32);
777 hashwrite_be32(f, offset & 0xffffffffUL);
778 written += 2 * sizeof(uint32_t);
779
780 nr_large_offset--;
781 }
782
783 return written;
784}
785
a3407730
DS
786int write_midx_file(const char *object_dir)
787{
32f3c541 788 unsigned char cur_chunk, num_chunks = 0;
fc59e748 789 char *midx_name;
396f2570 790 uint32_t i;
fc59e748
DS
791 struct hashfile *f = NULL;
792 struct lock_file lk;
396f2570 793 struct pack_list packs;
32f3c541
DS
794 uint32_t *pack_perm = NULL;
795 uint64_t written = 0;
796 uint32_t chunk_ids[MIDX_MAX_CHUNKS + 1];
797 uint64_t chunk_offsets[MIDX_MAX_CHUNKS + 1];
662148c4 798 uint32_t nr_entries, num_large_offsets = 0;
fe1ed56f 799 struct pack_midx_entry *entries = NULL;
662148c4 800 int large_offsets_needed = 0;
fc59e748
DS
801
802 midx_name = get_midx_filename(object_dir);
803 if (safe_create_leading_directories(midx_name)) {
804 UNLEAK(midx_name);
805 die_errno(_("unable to create leading directories of %s"),
806 midx_name);
807 }
808
2cf489a3 809 packs.m = load_multi_pack_index(object_dir, 1);
a40498a1 810
396f2570 811 packs.nr = 0;
a40498a1
DS
812 packs.alloc_list = packs.m ? packs.m->num_packs : 16;
813 packs.alloc_names = packs.alloc_list;
396f2570 814 packs.list = NULL;
a40498a1 815 packs.names = NULL;
32f3c541 816 packs.pack_name_concat_len = 0;
396f2570 817 ALLOC_ARRAY(packs.list, packs.alloc_list);
32f3c541 818 ALLOC_ARRAY(packs.names, packs.alloc_names);
396f2570 819
a40498a1
DS
820 if (packs.m) {
821 for (i = 0; i < packs.m->num_packs; i++) {
822 ALLOC_GROW(packs.list, packs.nr + 1, packs.alloc_list);
823 ALLOC_GROW(packs.names, packs.nr + 1, packs.alloc_names);
824
825 packs.list[packs.nr] = NULL;
826 packs.names[packs.nr] = xstrdup(packs.m->pack_names[i]);
827 packs.pack_name_concat_len += strlen(packs.names[packs.nr]) + 1;
828 packs.nr++;
829 }
830 }
831
396f2570
DS
832 for_each_file_in_pack_dir(object_dir, add_pack_to_midx, &packs);
833
a40498a1
DS
834 if (packs.m && packs.nr == packs.m->num_packs)
835 goto cleanup;
836
32f3c541
DS
837 if (packs.pack_name_concat_len % MIDX_CHUNK_ALIGNMENT)
838 packs.pack_name_concat_len += MIDX_CHUNK_ALIGNMENT -
839 (packs.pack_name_concat_len % MIDX_CHUNK_ALIGNMENT);
840
841 ALLOC_ARRAY(pack_perm, packs.nr);
842 sort_packs_by_name(packs.names, packs.nr, pack_perm);
843
a40498a1
DS
844 entries = get_sorted_entries(packs.m, packs.list, pack_perm, packs.nr, &nr_entries);
845
662148c4
DS
846 for (i = 0; i < nr_entries; i++) {
847 if (entries[i].offset > 0x7fffffff)
848 num_large_offsets++;
849 if (entries[i].offset > 0xffffffff)
850 large_offsets_needed = 1;
851 }
fe1ed56f 852
fc59e748
DS
853 hold_lock_file_for_update(&lk, midx_name, LOCK_DIE_ON_ERROR);
854 f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
855 FREE_AND_NULL(midx_name);
856
a40498a1
DS
857 if (packs.m)
858 close_midx(packs.m);
859
32f3c541 860 cur_chunk = 0;
662148c4 861 num_chunks = large_offsets_needed ? 5 : 4;
32f3c541
DS
862
863 written = write_midx_header(f, num_chunks, packs.nr);
864
865 chunk_ids[cur_chunk] = MIDX_CHUNKID_PACKNAMES;
866 chunk_offsets[cur_chunk] = written + (num_chunks + 1) * MIDX_CHUNKLOOKUP_WIDTH;
867
868 cur_chunk++;
d7cacf29 869 chunk_ids[cur_chunk] = MIDX_CHUNKID_OIDFANOUT;
32f3c541
DS
870 chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + packs.pack_name_concat_len;
871
d7cacf29
DS
872 cur_chunk++;
873 chunk_ids[cur_chunk] = MIDX_CHUNKID_OIDLOOKUP;
874 chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + MIDX_CHUNK_FANOUT_SIZE;
875
0d5b3a5e 876 cur_chunk++;
662148c4 877 chunk_ids[cur_chunk] = MIDX_CHUNKID_OBJECTOFFSETS;
0d5b3a5e
DS
878 chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + nr_entries * MIDX_HASH_LEN;
879
662148c4
DS
880 cur_chunk++;
881 chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + nr_entries * MIDX_CHUNK_OFFSET_WIDTH;
882 if (large_offsets_needed) {
883 chunk_ids[cur_chunk] = MIDX_CHUNKID_LARGEOFFSETS;
884
885 cur_chunk++;
886 chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] +
887 num_large_offsets * MIDX_CHUNK_LARGE_OFFSET_WIDTH;
888 }
889
890 chunk_ids[cur_chunk] = 0;
891
32f3c541
DS
892 for (i = 0; i <= num_chunks; i++) {
893 if (i && chunk_offsets[i] < chunk_offsets[i - 1])
894 BUG("incorrect chunk offsets: %"PRIu64" before %"PRIu64,
895 chunk_offsets[i - 1],
896 chunk_offsets[i]);
897
898 if (chunk_offsets[i] % MIDX_CHUNK_ALIGNMENT)
899 BUG("chunk offset %"PRIu64" is not properly aligned",
900 chunk_offsets[i]);
901
902 hashwrite_be32(f, chunk_ids[i]);
903 hashwrite_be32(f, chunk_offsets[i] >> 32);
904 hashwrite_be32(f, chunk_offsets[i]);
905
906 written += MIDX_CHUNKLOOKUP_WIDTH;
907 }
908
909 for (i = 0; i < num_chunks; i++) {
910 if (written != chunk_offsets[i])
911 BUG("incorrect chunk offset (%"PRIu64" != %"PRIu64") for chunk id %"PRIx32,
912 chunk_offsets[i],
913 written,
914 chunk_ids[i]);
915
916 switch (chunk_ids[i]) {
917 case MIDX_CHUNKID_PACKNAMES:
918 written += write_midx_pack_names(f, packs.names, packs.nr);
919 break;
920
d7cacf29
DS
921 case MIDX_CHUNKID_OIDFANOUT:
922 written += write_midx_oid_fanout(f, entries, nr_entries);
923 break;
924
0d5b3a5e
DS
925 case MIDX_CHUNKID_OIDLOOKUP:
926 written += write_midx_oid_lookup(f, MIDX_HASH_LEN, entries, nr_entries);
927 break;
928
662148c4
DS
929 case MIDX_CHUNKID_OBJECTOFFSETS:
930 written += write_midx_object_offsets(f, large_offsets_needed, entries, nr_entries);
931 break;
932
933 case MIDX_CHUNKID_LARGEOFFSETS:
934 written += write_midx_large_offsets(f, num_large_offsets, entries, nr_entries);
935 break;
936
32f3c541
DS
937 default:
938 BUG("trying to write unknown chunk id %"PRIx32,
939 chunk_ids[i]);
940 }
941 }
942
943 if (written != chunk_offsets[num_chunks])
944 BUG("incorrect final offset %"PRIu64" != %"PRIu64,
945 written,
946 chunk_offsets[num_chunks]);
fc59e748
DS
947
948 finalize_hashfile(f, NULL, CSUM_FSYNC | CSUM_HASH_IN_STREAM);
949 commit_lock_file(&lk);
950
a40498a1 951cleanup:
396f2570
DS
952 for (i = 0; i < packs.nr; i++) {
953 if (packs.list[i]) {
954 close_pack(packs.list[i]);
955 free(packs.list[i]);
956 }
32f3c541 957 free(packs.names[i]);
396f2570
DS
958 }
959
960 free(packs.list);
32f3c541 961 free(packs.names);
fe1ed56f 962 free(entries);
a40498a1
DS
963 free(pack_perm);
964 free(midx_name);
a3407730
DS
965 return 0;
966}
525e18c0 967
1dcd9f20 968void clear_midx_file(struct repository *r)
525e18c0 969{
3b2f8a02 970 char *midx = get_midx_filename(r->objects->odb->path);
1dcd9f20
DS
971
972 if (r->objects && r->objects->multi_pack_index) {
973 close_midx(r->objects->multi_pack_index);
974 r->objects->multi_pack_index = NULL;
975 }
525e18c0
DS
976
977 if (remove_path(midx)) {
978 UNLEAK(midx);
979 die(_("failed to clear multi-pack-index at %s"), midx);
980 }
981
982 free(midx);
983}
56ee7ff1
DS
984
985static int verify_midx_error;
986
d4bf1d88
DS
987static void midx_report(const char *fmt, ...)
988{
989 va_list ap;
990 verify_midx_error = 1;
991 va_start(ap, fmt);
992 vfprintf(stderr, fmt, ap);
993 fprintf(stderr, "\n");
994 va_end(ap);
995}
996
5ae18df9
JH
997struct pair_pos_vs_id
998{
999 uint32_t pos;
1000 uint32_t pack_int_id;
1001};
1002
1003static int compare_pair_pos_vs_id(const void *_a, const void *_b)
1004{
1005 struct pair_pos_vs_id *a = (struct pair_pos_vs_id *)_a;
1006 struct pair_pos_vs_id *b = (struct pair_pos_vs_id *)_b;
1007
1008 return b->pack_int_id - a->pack_int_id;
1009}
1010
430efb8a
JH
1011/*
1012 * Limit calls to display_progress() for performance reasons.
1013 * The interval here was arbitrarily chosen.
1014 */
1015#define SPARSE_PROGRESS_INTERVAL (1 << 12)
1016#define midx_display_sparse_progress(progress, n) \
1017 do { \
1018 uint64_t _n = (n); \
1019 if ((_n & (SPARSE_PROGRESS_INTERVAL - 1)) == 0) \
1020 display_progress(progress, _n); \
1021 } while (0)
1022
56ee7ff1
DS
1023int verify_midx_file(const char *object_dir)
1024{
5ae18df9 1025 struct pair_pos_vs_id *pairs = NULL;
d4bf1d88 1026 uint32_t i;
17eeb067 1027 struct progress *progress;
56ee7ff1
DS
1028 struct multi_pack_index *m = load_multi_pack_index(object_dir, 1);
1029 verify_midx_error = 0;
1030
1031 if (!m)
1032 return 0;
1033
430efb8a
JH
1034 progress = start_progress(_("Looking for referenced packfiles"),
1035 m->num_packs);
d4bf1d88
DS
1036 for (i = 0; i < m->num_packs; i++) {
1037 if (prepare_midx_pack(m, i))
1038 midx_report("failed to load pack in position %d", i);
430efb8a
JH
1039
1040 display_progress(progress, i + 1);
d4bf1d88 1041 }
430efb8a 1042 stop_progress(&progress);
d4bf1d88 1043
2f23d3f3
DS
1044 for (i = 0; i < 255; i++) {
1045 uint32_t oid_fanout1 = ntohl(m->chunk_oid_fanout[i]);
1046 uint32_t oid_fanout2 = ntohl(m->chunk_oid_fanout[i + 1]);
1047
1048 if (oid_fanout1 > oid_fanout2)
1049 midx_report(_("oid fanout out of order: fanout[%d] = %"PRIx32" > %"PRIx32" = fanout[%d]"),
1050 i, oid_fanout1, oid_fanout2, i + 1);
1051 }
1052
430efb8a
JH
1053 progress = start_sparse_progress(_("Verifying OID order in MIDX"),
1054 m->num_objects - 1);
55c5648d
DS
1055 for (i = 0; i < m->num_objects - 1; i++) {
1056 struct object_id oid1, oid2;
1057
1058 nth_midxed_object_oid(&oid1, m, i);
1059 nth_midxed_object_oid(&oid2, m, i + 1);
1060
1061 if (oidcmp(&oid1, &oid2) >= 0)
1062 midx_report(_("oid lookup out of order: oid[%d] = %s >= %s = oid[%d]"),
1063 i, oid_to_hex(&oid1), oid_to_hex(&oid2), i + 1);
430efb8a
JH
1064
1065 midx_display_sparse_progress(progress, i + 1);
55c5648d 1066 }
430efb8a 1067 stop_progress(&progress);
55c5648d 1068
5ae18df9
JH
1069 /*
1070 * Create an array mapping each object to its packfile id. Sort it
1071 * to group the objects by packfile. Use this permutation to visit
1072 * each of the objects and only require 1 packfile to be open at a
1073 * time.
1074 */
1075 ALLOC_ARRAY(pairs, m->num_objects);
1076 for (i = 0; i < m->num_objects; i++) {
1077 pairs[i].pos = i;
1078 pairs[i].pack_int_id = nth_midxed_pack_int_id(m, i);
1079 }
1080
1081 progress = start_sparse_progress(_("Sorting objects by packfile"),
1082 m->num_objects);
1083 display_progress(progress, 0); /* TODO: Measure QSORT() progress */
1084 QSORT(pairs, m->num_objects, compare_pair_pos_vs_id);
1085 stop_progress(&progress);
1086
430efb8a 1087 progress = start_sparse_progress(_("Verifying object offsets"), m->num_objects);
cc6af73c
DS
1088 for (i = 0; i < m->num_objects; i++) {
1089 struct object_id oid;
1090 struct pack_entry e;
1091 off_t m_offset, p_offset;
1092
5ae18df9
JH
1093 if (i > 0 && pairs[i-1].pack_int_id != pairs[i].pack_int_id &&
1094 m->packs[pairs[i-1].pack_int_id])
1095 {
1096 close_pack_fd(m->packs[pairs[i-1].pack_int_id]);
1097 close_pack_index(m->packs[pairs[i-1].pack_int_id]);
1098 }
1099
1100 nth_midxed_object_oid(&oid, m, pairs[i].pos);
1101
cc6af73c
DS
1102 if (!fill_midx_entry(&oid, &e, m)) {
1103 midx_report(_("failed to load pack entry for oid[%d] = %s"),
5ae18df9 1104 pairs[i].pos, oid_to_hex(&oid));
cc6af73c
DS
1105 continue;
1106 }
1107
1108 if (open_pack_index(e.p)) {
1109 midx_report(_("failed to load pack-index for packfile %s"),
1110 e.p->pack_name);
1111 break;
1112 }
1113
1114 m_offset = e.offset;
1115 p_offset = find_pack_entry_one(oid.hash, e.p);
1116
1117 if (m_offset != p_offset)
1118 midx_report(_("incorrect object offset for oid[%d] = %s: %"PRIx64" != %"PRIx64),
5ae18df9 1119 pairs[i].pos, oid_to_hex(&oid), m_offset, p_offset);
144d7033 1120
430efb8a 1121 midx_display_sparse_progress(progress, i + 1);
cc6af73c 1122 }
144d7033 1123 stop_progress(&progress);
cc6af73c 1124
5ae18df9
JH
1125 free(pairs);
1126
56ee7ff1
DS
1127 return verify_midx_error;
1128}