Merge branch 'ds/commit-graph-fsck' into jt/commit-graph-per-object-store
[git/git.git] / commit-graph.c
CommitLineData
08fd81c9
DS
1#include "cache.h"
2#include "config.h"
33286dcd 3#include "dir.h"
08fd81c9
DS
4#include "git-compat-util.h"
5#include "lockfile.h"
6#include "pack.h"
7#include "packfile.h"
8#include "commit.h"
9#include "object.h"
59fb8770 10#include "refs.h"
08fd81c9
DS
11#include "revision.h"
12#include "sha1-lookup.h"
13#include "commit-graph.h"
b10edb2d 14#include "object-store.h"
96af91d4 15#include "alloc.h"
08fd81c9
DS
16
17#define GRAPH_SIGNATURE 0x43475048 /* "CGPH" */
18#define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
19#define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
20#define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
21#define GRAPH_CHUNKID_LARGEEDGES 0x45444745 /* "EDGE" */
22
23#define GRAPH_DATA_WIDTH 36
24
25#define GRAPH_VERSION_1 0x1
26#define GRAPH_VERSION GRAPH_VERSION_1
27
28#define GRAPH_OID_VERSION_SHA1 1
29#define GRAPH_OID_LEN_SHA1 GIT_SHA1_RAWSZ
30#define GRAPH_OID_VERSION GRAPH_OID_VERSION_SHA1
31#define GRAPH_OID_LEN GRAPH_OID_LEN_SHA1
32
33#define GRAPH_OCTOPUS_EDGES_NEEDED 0x80000000
34#define GRAPH_PARENT_MISSING 0x7fffffff
35#define GRAPH_EDGE_LAST_MASK 0x7fffffff
36#define GRAPH_PARENT_NONE 0x70000000
37
38#define GRAPH_LAST_EDGE 0x80000000
39
0e3b97cc 40#define GRAPH_HEADER_SIZE 8
08fd81c9
DS
41#define GRAPH_FANOUT_SIZE (4 * 256)
42#define GRAPH_CHUNKLOOKUP_WIDTH 12
0e3b97cc
DS
43#define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
44 + GRAPH_FANOUT_SIZE + GRAPH_OID_LEN)
08fd81c9 45
2a2e32bd 46char *get_commit_graph_filename(const char *obj_dir)
08fd81c9
DS
47{
48 return xstrfmt("%s/info/commit-graph", obj_dir);
49}
50
2a2e32bd
DS
51static struct commit_graph *alloc_commit_graph(void)
52{
53 struct commit_graph *g = xcalloc(1, sizeof(*g));
54 g->graph_fd = -1;
55
56 return g;
57}
58
59struct commit_graph *load_commit_graph_one(const char *graph_file)
60{
61 void *graph_map;
62 const unsigned char *data, *chunk_lookup;
63 size_t graph_size;
64 struct stat st;
65 uint32_t i;
66 struct commit_graph *graph;
67 int fd = git_open(graph_file);
68 uint64_t last_chunk_offset;
69 uint32_t last_chunk_id;
70 uint32_t graph_signature;
71 unsigned char graph_version, hash_version;
72
73 if (fd < 0)
74 return NULL;
75 if (fstat(fd, &st)) {
76 close(fd);
77 return NULL;
78 }
79 graph_size = xsize_t(st.st_size);
80
81 if (graph_size < GRAPH_MIN_SIZE) {
82 close(fd);
83 die("graph file %s is too small", graph_file);
84 }
85 graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
86 data = (const unsigned char *)graph_map;
87
88 graph_signature = get_be32(data);
89 if (graph_signature != GRAPH_SIGNATURE) {
90 error("graph signature %X does not match signature %X",
91 graph_signature, GRAPH_SIGNATURE);
92 goto cleanup_fail;
93 }
94
95 graph_version = *(unsigned char*)(data + 4);
96 if (graph_version != GRAPH_VERSION) {
97 error("graph version %X does not match version %X",
98 graph_version, GRAPH_VERSION);
99 goto cleanup_fail;
100 }
101
102 hash_version = *(unsigned char*)(data + 5);
103 if (hash_version != GRAPH_OID_VERSION) {
104 error("hash version %X does not match version %X",
105 hash_version, GRAPH_OID_VERSION);
106 goto cleanup_fail;
107 }
108
109 graph = alloc_commit_graph();
110
111 graph->hash_len = GRAPH_OID_LEN;
112 graph->num_chunks = *(unsigned char*)(data + 6);
113 graph->graph_fd = fd;
114 graph->data = graph_map;
115 graph->data_len = graph_size;
116
117 last_chunk_id = 0;
118 last_chunk_offset = 8;
119 chunk_lookup = data + 8;
120 for (i = 0; i < graph->num_chunks; i++) {
121 uint32_t chunk_id = get_be32(chunk_lookup + 0);
122 uint64_t chunk_offset = get_be64(chunk_lookup + 4);
123 int chunk_repeated = 0;
124
125 chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
126
127 if (chunk_offset > graph_size - GIT_MAX_RAWSZ) {
128 error("improper chunk offset %08x%08x", (uint32_t)(chunk_offset >> 32),
129 (uint32_t)chunk_offset);
130 goto cleanup_fail;
131 }
132
133 switch (chunk_id) {
134 case GRAPH_CHUNKID_OIDFANOUT:
135 if (graph->chunk_oid_fanout)
136 chunk_repeated = 1;
137 else
138 graph->chunk_oid_fanout = (uint32_t*)(data + chunk_offset);
139 break;
140
141 case GRAPH_CHUNKID_OIDLOOKUP:
142 if (graph->chunk_oid_lookup)
143 chunk_repeated = 1;
144 else
145 graph->chunk_oid_lookup = data + chunk_offset;
146 break;
147
148 case GRAPH_CHUNKID_DATA:
149 if (graph->chunk_commit_data)
150 chunk_repeated = 1;
151 else
152 graph->chunk_commit_data = data + chunk_offset;
153 break;
154
155 case GRAPH_CHUNKID_LARGEEDGES:
156 if (graph->chunk_large_edges)
157 chunk_repeated = 1;
158 else
159 graph->chunk_large_edges = data + chunk_offset;
160 break;
161 }
162
163 if (chunk_repeated) {
164 error("chunk id %08x appears multiple times", chunk_id);
165 goto cleanup_fail;
166 }
167
168 if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP)
169 {
170 graph->num_commits = (chunk_offset - last_chunk_offset)
171 / graph->hash_len;
172 }
173
174 last_chunk_id = chunk_id;
175 last_chunk_offset = chunk_offset;
176 }
177
178 return graph;
179
180cleanup_fail:
181 munmap(graph_map, graph_size);
182 close(fd);
183 exit(1);
184}
185
177722b3
DS
186/* global storage */
187static struct commit_graph *commit_graph = NULL;
188
189static void prepare_commit_graph_one(const char *obj_dir)
190{
191 char *graph_name;
192
193 if (commit_graph)
194 return;
195
196 graph_name = get_commit_graph_filename(obj_dir);
197 commit_graph = load_commit_graph_one(graph_name);
198
199 FREE_AND_NULL(graph_name);
200}
201
202static int prepare_commit_graph_run_once = 0;
203static void prepare_commit_graph(void)
204{
205 struct alternate_object_database *alt;
206 char *obj_dir;
207
208 if (prepare_commit_graph_run_once)
209 return;
210 prepare_commit_graph_run_once = 1;
211
212 obj_dir = get_object_directory();
213 prepare_commit_graph_one(obj_dir);
b10edb2d
JH
214 prepare_alt_odb(the_repository);
215 for (alt = the_repository->objects->alt_odb_list;
216 !commit_graph && alt;
217 alt = alt->next)
177722b3
DS
218 prepare_commit_graph_one(alt->path);
219}
220
221static void close_commit_graph(void)
222{
223 if (!commit_graph)
224 return;
225
226 if (commit_graph->graph_fd >= 0) {
227 munmap((void *)commit_graph->data, commit_graph->data_len);
228 commit_graph->data = NULL;
229 close(commit_graph->graph_fd);
230 }
231
232 FREE_AND_NULL(commit_graph);
233}
234
235static int bsearch_graph(struct commit_graph *g, struct object_id *oid, uint32_t *pos)
236{
237 return bsearch_hash(oid->hash, g->chunk_oid_fanout,
238 g->chunk_oid_lookup, g->hash_len, pos);
239}
240
241static struct commit_list **insert_parent_or_die(struct commit_graph *g,
242 uint64_t pos,
243 struct commit_list **pptr)
244{
245 struct commit *c;
246 struct object_id oid;
96af91d4 247
53614b13
DS
248 if (pos >= g->num_commits)
249 die("invalid parent position %"PRIu64, pos);
250
177722b3 251 hashcpy(oid.hash, g->chunk_oid_lookup + g->hash_len * pos);
c1f5eb49 252 c = lookup_commit(the_repository, &oid);
177722b3
DS
253 if (!c)
254 die("could not find commit %s", oid_to_hex(&oid));
255 c->graph_pos = pos;
256 return &commit_list_insert(c, pptr)->next;
257}
258
e2838d85
DS
259static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
260{
261 const unsigned char *commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * pos;
262 item->graph_pos = pos;
263 item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
264}
265
177722b3
DS
266static int fill_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t pos)
267{
177722b3
DS
268 uint32_t edge_value;
269 uint32_t *parent_data_ptr;
270 uint64_t date_low, date_high;
271 struct commit_list **pptr;
272 const unsigned char *commit_data = g->chunk_commit_data + (g->hash_len + 16) * pos;
273
274 item->object.parsed = 1;
275 item->graph_pos = pos;
276
7b8a21db 277 item->maybe_tree = NULL;
177722b3
DS
278
279 date_high = get_be32(commit_data + g->hash_len + 8) & 0x3;
280 date_low = get_be32(commit_data + g->hash_len + 12);
281 item->date = (timestamp_t)((date_high << 32) | date_low);
282
83073cc9
DS
283 item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
284
177722b3
DS
285 pptr = &item->parents;
286
287 edge_value = get_be32(commit_data + g->hash_len);
288 if (edge_value == GRAPH_PARENT_NONE)
289 return 1;
290 pptr = insert_parent_or_die(g, edge_value, pptr);
291
292 edge_value = get_be32(commit_data + g->hash_len + 4);
293 if (edge_value == GRAPH_PARENT_NONE)
294 return 1;
295 if (!(edge_value & GRAPH_OCTOPUS_EDGES_NEEDED)) {
296 pptr = insert_parent_or_die(g, edge_value, pptr);
297 return 1;
298 }
299
300 parent_data_ptr = (uint32_t*)(g->chunk_large_edges +
301 4 * (uint64_t)(edge_value & GRAPH_EDGE_LAST_MASK));
302 do {
303 edge_value = get_be32(parent_data_ptr);
304 pptr = insert_parent_or_die(g,
305 edge_value & GRAPH_EDGE_LAST_MASK,
306 pptr);
307 parent_data_ptr++;
308 } while (!(edge_value & GRAPH_LAST_EDGE));
309
310 return 1;
311}
312
e2838d85
DS
313static int find_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t *pos)
314{
315 if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
316 *pos = item->graph_pos;
317 return 1;
318 } else {
319 return bsearch_graph(g, &(item->object.oid), pos);
320 }
321}
322
ee797053 323static int parse_commit_in_graph_one(struct commit_graph *g, struct commit *item)
177722b3 324{
e2838d85
DS
325 uint32_t pos;
326
177722b3
DS
327 if (!core_commit_graph)
328 return 0;
329 if (item->object.parsed)
330 return 1;
ee797053
DS
331
332 if (find_commit_in_graph(item, g, &pos))
333 return fill_commit_in_graph(item, g, pos);
334
335 return 0;
336}
337
338int parse_commit_in_graph(struct commit *item)
339{
340 if (!core_commit_graph)
341 return 0;
342
177722b3 343 prepare_commit_graph();
ee797053
DS
344 if (commit_graph)
345 return parse_commit_in_graph_one(commit_graph, item);
177722b3
DS
346 return 0;
347}
348
e2838d85
DS
349void load_commit_graph_info(struct commit *item)
350{
351 uint32_t pos;
352 if (!core_commit_graph)
353 return;
354 prepare_commit_graph();
355 if (commit_graph && find_commit_in_graph(item, commit_graph, &pos))
356 fill_commit_graph_info(item, commit_graph, pos);
357}
358
7b8a21db
DS
359static struct tree *load_tree_for_commit(struct commit_graph *g, struct commit *c)
360{
361 struct object_id oid;
362 const unsigned char *commit_data = g->chunk_commit_data +
363 GRAPH_DATA_WIDTH * (c->graph_pos);
364
365 hashcpy(oid.hash, commit_data);
f86bcc7b 366 c->maybe_tree = lookup_tree(the_repository, &oid);
7b8a21db
DS
367
368 return c->maybe_tree;
369}
370
0cbef8f8
DS
371static struct tree *get_commit_tree_in_graph_one(struct commit_graph *g,
372 const struct commit *c)
7b8a21db
DS
373{
374 if (c->maybe_tree)
375 return c->maybe_tree;
376 if (c->graph_pos == COMMIT_NOT_FROM_GRAPH)
0cbef8f8
DS
377 BUG("get_commit_tree_in_graph_one called from non-commit-graph commit");
378
379 return load_tree_for_commit(g, (struct commit *)c);
380}
7b8a21db 381
0cbef8f8
DS
382struct tree *get_commit_tree_in_graph(const struct commit *c)
383{
384 return get_commit_tree_in_graph_one(commit_graph, c);
7b8a21db
DS
385}
386
08fd81c9
DS
387static void write_graph_chunk_fanout(struct hashfile *f,
388 struct commit **commits,
389 int nr_commits)
390{
391 int i, count = 0;
392 struct commit **list = commits;
393
394 /*
395 * Write the first-level table (the list is sorted,
396 * but we use a 256-entry lookup to be able to avoid
397 * having to do eight extra binary search iterations).
398 */
399 for (i = 0; i < 256; i++) {
400 while (count < nr_commits) {
401 if ((*list)->object.oid.hash[0] != i)
402 break;
403 count++;
404 list++;
405 }
406
407 hashwrite_be32(f, count);
408 }
409}
410
411static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
412 struct commit **commits, int nr_commits)
413{
414 struct commit **list = commits;
415 int count;
416 for (count = 0; count < nr_commits; count++, list++)
417 hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
418}
419
420static const unsigned char *commit_to_sha1(size_t index, void *table)
421{
422 struct commit **commits = table;
423 return commits[index]->object.oid.hash;
424}
425
426static void write_graph_chunk_data(struct hashfile *f, int hash_len,
427 struct commit **commits, int nr_commits)
428{
429 struct commit **list = commits;
430 struct commit **last = commits + nr_commits;
431 uint32_t num_extra_edges = 0;
432
433 while (list < last) {
434 struct commit_list *parent;
435 int edge_value;
436 uint32_t packedDate[2];
437
438 parse_commit(*list);
2e27bd77 439 hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
08fd81c9
DS
440
441 parent = (*list)->parents;
442
443 if (!parent)
444 edge_value = GRAPH_PARENT_NONE;
445 else {
446 edge_value = sha1_pos(parent->item->object.oid.hash,
447 commits,
448 nr_commits,
449 commit_to_sha1);
450
451 if (edge_value < 0)
452 edge_value = GRAPH_PARENT_MISSING;
453 }
454
455 hashwrite_be32(f, edge_value);
456
457 if (parent)
458 parent = parent->next;
459
460 if (!parent)
461 edge_value = GRAPH_PARENT_NONE;
462 else if (parent->next)
463 edge_value = GRAPH_OCTOPUS_EDGES_NEEDED | num_extra_edges;
464 else {
465 edge_value = sha1_pos(parent->item->object.oid.hash,
466 commits,
467 nr_commits,
468 commit_to_sha1);
469 if (edge_value < 0)
470 edge_value = GRAPH_PARENT_MISSING;
471 }
472
473 hashwrite_be32(f, edge_value);
474
475 if (edge_value & GRAPH_OCTOPUS_EDGES_NEEDED) {
476 do {
477 num_extra_edges++;
478 parent = parent->next;
479 } while (parent);
480 }
481
482 if (sizeof((*list)->date) > 4)
483 packedDate[0] = htonl(((*list)->date >> 32) & 0x3);
484 else
485 packedDate[0] = 0;
486
3258c663
DS
487 packedDate[0] |= htonl((*list)->generation << 2);
488
08fd81c9
DS
489 packedDate[1] = htonl((*list)->date);
490 hashwrite(f, packedDate, 8);
491
492 list++;
493 }
494}
495
496static void write_graph_chunk_large_edges(struct hashfile *f,
497 struct commit **commits,
498 int nr_commits)
499{
500 struct commit **list = commits;
501 struct commit **last = commits + nr_commits;
502 struct commit_list *parent;
503
504 while (list < last) {
505 int num_parents = 0;
506 for (parent = (*list)->parents; num_parents < 3 && parent;
507 parent = parent->next)
508 num_parents++;
509
510 if (num_parents <= 2) {
511 list++;
512 continue;
513 }
514
515 /* Since num_parents > 2, this initializer is safe. */
516 for (parent = (*list)->parents->next; parent; parent = parent->next) {
517 int edge_value = sha1_pos(parent->item->object.oid.hash,
518 commits,
519 nr_commits,
520 commit_to_sha1);
521
522 if (edge_value < 0)
523 edge_value = GRAPH_PARENT_MISSING;
524 else if (!parent->next)
525 edge_value |= GRAPH_LAST_EDGE;
526
527 hashwrite_be32(f, edge_value);
528 }
529
530 list++;
531 }
532}
533
534static int commit_compare(const void *_a, const void *_b)
535{
536 const struct object_id *a = (const struct object_id *)_a;
537 const struct object_id *b = (const struct object_id *)_b;
538 return oidcmp(a, b);
539}
540
541struct packed_commit_list {
542 struct commit **list;
543 int nr;
544 int alloc;
545};
546
547struct packed_oid_list {
548 struct object_id *list;
549 int nr;
550 int alloc;
551};
552
553static int add_packed_commits(const struct object_id *oid,
554 struct packed_git *pack,
555 uint32_t pos,
556 void *data)
557{
558 struct packed_oid_list *list = (struct packed_oid_list*)data;
559 enum object_type type;
560 off_t offset = nth_packed_object_offset(pack, pos);
561 struct object_info oi = OBJECT_INFO_INIT;
562
563 oi.typep = &type;
fcb6df32 564 if (packed_object_info(the_repository, pack, offset, &oi) < 0)
08fd81c9
DS
565 die("unable to get type of object %s", oid_to_hex(oid));
566
567 if (type != OBJ_COMMIT)
568 return 0;
569
570 ALLOC_GROW(list->list, list->nr + 1, list->alloc);
571 oidcpy(&(list->list[list->nr]), oid);
572 list->nr++;
573
574 return 0;
575}
576
4f2542b4
DS
577static void add_missing_parents(struct packed_oid_list *oids, struct commit *commit)
578{
579 struct commit_list *parent;
580 for (parent = commit->parents; parent; parent = parent->next) {
581 if (!(parent->item->object.flags & UNINTERESTING)) {
582 ALLOC_GROW(oids->list, oids->nr + 1, oids->alloc);
583 oidcpy(&oids->list[oids->nr], &(parent->item->object.oid));
584 oids->nr++;
585 parent->item->object.flags |= UNINTERESTING;
586 }
587 }
588}
589
590static void close_reachable(struct packed_oid_list *oids)
591{
592 int i;
593 struct commit *commit;
594
595 for (i = 0; i < oids->nr; i++) {
c1f5eb49 596 commit = lookup_commit(the_repository, &oids->list[i]);
4f2542b4
DS
597 if (commit)
598 commit->object.flags |= UNINTERESTING;
599 }
600
601 /*
602 * As this loop runs, oids->nr may grow, but not more
603 * than the number of missing commits in the reachable
604 * closure.
605 */
606 for (i = 0; i < oids->nr; i++) {
c1f5eb49 607 commit = lookup_commit(the_repository, &oids->list[i]);
4f2542b4
DS
608
609 if (commit && !parse_commit(commit))
610 add_missing_parents(oids, commit);
611 }
612
613 for (i = 0; i < oids->nr; i++) {
c1f5eb49 614 commit = lookup_commit(the_repository, &oids->list[i]);
4f2542b4
DS
615
616 if (commit)
617 commit->object.flags &= ~UNINTERESTING;
618 }
619}
620
3258c663
DS
621static void compute_generation_numbers(struct packed_commit_list* commits)
622{
623 int i;
624 struct commit_list *list = NULL;
625
626 for (i = 0; i < commits->nr; i++) {
627 if (commits->list[i]->generation != GENERATION_NUMBER_INFINITY &&
628 commits->list[i]->generation != GENERATION_NUMBER_ZERO)
629 continue;
630
631 commit_list_insert(commits->list[i], &list);
632 while (list) {
633 struct commit *current = list->item;
634 struct commit_list *parent;
635 int all_parents_computed = 1;
636 uint32_t max_generation = 0;
637
638 for (parent = current->parents; parent; parent = parent->next) {
639 if (parent->item->generation == GENERATION_NUMBER_INFINITY ||
640 parent->item->generation == GENERATION_NUMBER_ZERO) {
641 all_parents_computed = 0;
642 commit_list_insert(parent->item, &list);
643 break;
644 } else if (parent->item->generation > max_generation) {
645 max_generation = parent->item->generation;
646 }
647 }
648
649 if (all_parents_computed) {
650 current->generation = max_generation + 1;
651 pop_commit(&list);
652
653 if (current->generation > GENERATION_NUMBER_MAX)
654 current->generation = GENERATION_NUMBER_MAX;
655 }
656 }
657 }
658}
659
59fb8770
DS
660static int add_ref_to_list(const char *refname,
661 const struct object_id *oid,
662 int flags, void *cb_data)
663{
664 struct string_list *list = (struct string_list *)cb_data;
665
666 string_list_append(list, oid_to_hex(oid));
667 return 0;
668}
669
670void write_commit_graph_reachable(const char *obj_dir, int append)
671{
672 struct string_list list;
673
674 string_list_init(&list, 1);
675 for_each_ref(add_ref_to_list, &list);
676 write_commit_graph(obj_dir, NULL, &list, append);
677}
678
049d51a2 679void write_commit_graph(const char *obj_dir,
d88b14b3
DS
680 struct string_list *pack_indexes,
681 struct string_list *commit_hex,
7547b95b 682 int append)
08fd81c9
DS
683{
684 struct packed_oid_list oids;
685 struct packed_commit_list commits;
686 struct hashfile *f;
687 uint32_t i, count_distinct = 0;
688 char *graph_name;
08fd81c9
DS
689 struct lock_file lk = LOCK_INIT;
690 uint32_t chunk_ids[5];
691 uint64_t chunk_offsets[5];
692 int num_chunks;
693 int num_extra_edges;
694 struct commit_list *parent;
695
696 oids.nr = 0;
697 oids.alloc = approximate_object_count() / 4;
698
7547b95b
DS
699 if (append) {
700 prepare_commit_graph_one(obj_dir);
701 if (commit_graph)
702 oids.alloc += commit_graph->num_commits;
703 }
704
08fd81c9
DS
705 if (oids.alloc < 1024)
706 oids.alloc = 1024;
707 ALLOC_ARRAY(oids.list, oids.alloc);
708
7547b95b
DS
709 if (append && commit_graph) {
710 for (i = 0; i < commit_graph->num_commits; i++) {
711 const unsigned char *hash = commit_graph->chunk_oid_lookup +
712 commit_graph->hash_len * i;
713 hashcpy(oids.list[oids.nr++].hash, hash);
714 }
715 }
716
049d51a2
DS
717 if (pack_indexes) {
718 struct strbuf packname = STRBUF_INIT;
719 int dirlen;
720 strbuf_addf(&packname, "%s/pack/", obj_dir);
721 dirlen = packname.len;
d88b14b3 722 for (i = 0; i < pack_indexes->nr; i++) {
049d51a2
DS
723 struct packed_git *p;
724 strbuf_setlen(&packname, dirlen);
d88b14b3 725 strbuf_addstr(&packname, pack_indexes->items[i].string);
049d51a2
DS
726 p = add_packed_git(packname.buf, packname.len, 1);
727 if (!p)
728 die("error adding pack %s", packname.buf);
729 if (open_pack_index(p))
730 die("error opening index for %s", packname.buf);
731 for_each_object_in_pack(p, add_packed_commits, &oids);
732 close_pack(p);
733 }
734 strbuf_release(&packname);
3d5df01b
DS
735 }
736
737 if (commit_hex) {
d88b14b3 738 for (i = 0; i < commit_hex->nr; i++) {
3d5df01b
DS
739 const char *end;
740 struct object_id oid;
741 struct commit *result;
742
d88b14b3
DS
743 if (commit_hex->items[i].string &&
744 parse_oid_hex(commit_hex->items[i].string, &oid, &end))
3d5df01b
DS
745 continue;
746
21e1ee8f 747 result = lookup_commit_reference_gently(the_repository, &oid, 1);
3d5df01b
DS
748
749 if (result) {
750 ALLOC_GROW(oids.list, oids.nr + 1, oids.alloc);
751 oidcpy(&oids.list[oids.nr], &(result->object.oid));
752 oids.nr++;
753 }
754 }
755 }
756
757 if (!pack_indexes && !commit_hex)
049d51a2
DS
758 for_each_packed_object(add_packed_commits, &oids, 0);
759
4f2542b4 760 close_reachable(&oids);
08fd81c9
DS
761
762 QSORT(oids.list, oids.nr, commit_compare);
763
764 count_distinct = 1;
765 for (i = 1; i < oids.nr; i++) {
766 if (oidcmp(&oids.list[i-1], &oids.list[i]))
767 count_distinct++;
768 }
769
770 if (count_distinct >= GRAPH_PARENT_MISSING)
771 die(_("the commit graph format cannot write %d commits"), count_distinct);
772
773 commits.nr = 0;
774 commits.alloc = count_distinct;
775 ALLOC_ARRAY(commits.list, commits.alloc);
776
777 num_extra_edges = 0;
778 for (i = 0; i < oids.nr; i++) {
779 int num_parents = 0;
780 if (i > 0 && !oidcmp(&oids.list[i-1], &oids.list[i]))
781 continue;
782
c1f5eb49 783 commits.list[commits.nr] = lookup_commit(the_repository, &oids.list[i]);
08fd81c9
DS
784 parse_commit(commits.list[commits.nr]);
785
786 for (parent = commits.list[commits.nr]->parents;
787 parent; parent = parent->next)
788 num_parents++;
789
790 if (num_parents > 2)
791 num_extra_edges += num_parents - 1;
792
793 commits.nr++;
794 }
795 num_chunks = num_extra_edges ? 4 : 3;
796
797 if (commits.nr >= GRAPH_PARENT_MISSING)
798 die(_("too many commits to write graph"));
799
3258c663 800 compute_generation_numbers(&commits);
08fd81c9 801
08fd81c9 802 graph_name = get_commit_graph_filename(obj_dir);
33286dcd
DS
803 if (safe_create_leading_directories(graph_name))
804 die_errno(_("unable to create leading directories of %s"),
805 graph_name);
08fd81c9 806
33286dcd 807 hold_lock_file_for_update(&lk, graph_name, LOCK_DIE_ON_ERROR);
08fd81c9
DS
808 f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
809
810 hashwrite_be32(f, GRAPH_SIGNATURE);
811
812 hashwrite_u8(f, GRAPH_VERSION);
813 hashwrite_u8(f, GRAPH_OID_VERSION);
814 hashwrite_u8(f, num_chunks);
815 hashwrite_u8(f, 0); /* unused padding byte */
816
817 chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
818 chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
819 chunk_ids[2] = GRAPH_CHUNKID_DATA;
820 if (num_extra_edges)
821 chunk_ids[3] = GRAPH_CHUNKID_LARGEEDGES;
822 else
823 chunk_ids[3] = 0;
824 chunk_ids[4] = 0;
825
826 chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
827 chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
828 chunk_offsets[2] = chunk_offsets[1] + GRAPH_OID_LEN * commits.nr;
829 chunk_offsets[3] = chunk_offsets[2] + (GRAPH_OID_LEN + 16) * commits.nr;
830 chunk_offsets[4] = chunk_offsets[3] + 4 * num_extra_edges;
831
832 for (i = 0; i <= num_chunks; i++) {
833 uint32_t chunk_write[3];
834
835 chunk_write[0] = htonl(chunk_ids[i]);
836 chunk_write[1] = htonl(chunk_offsets[i] >> 32);
837 chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
838 hashwrite(f, chunk_write, 12);
839 }
840
841 write_graph_chunk_fanout(f, commits.list, commits.nr);
842 write_graph_chunk_oids(f, GRAPH_OID_LEN, commits.list, commits.nr);
843 write_graph_chunk_data(f, GRAPH_OID_LEN, commits.list, commits.nr);
844 write_graph_chunk_large_edges(f, commits.list, commits.nr);
845
177722b3 846 close_commit_graph();
08fd81c9
DS
847 finalize_hashfile(f, NULL, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
848 commit_lock_file(&lk);
849
850 free(oids.list);
851 oids.alloc = 0;
852 oids.nr = 0;
853}
283e68c7 854
41df0e30 855#define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
283e68c7
DS
856static int verify_commit_graph_error;
857
858static void graph_report(const char *fmt, ...)
859{
860 va_list ap;
861
862 verify_commit_graph_error = 1;
863 va_start(ap, fmt);
864 vfprintf(stderr, fmt, ap);
865 fprintf(stderr, "\n");
866 va_end(ap);
867}
868
1373e547
DS
869#define GENERATION_ZERO_EXISTS 1
870#define GENERATION_NUMBER_EXISTS 2
871
283e68c7
DS
872int verify_commit_graph(struct repository *r, struct commit_graph *g)
873{
9bda8467 874 uint32_t i, cur_fanout_pos = 0;
41df0e30 875 struct object_id prev_oid, cur_oid, checksum;
1373e547 876 int generation_zero = 0;
41df0e30
DS
877 struct hashfile *f;
878 int devnull;
9bda8467 879
283e68c7
DS
880 if (!g) {
881 graph_report("no commit-graph file loaded");
882 return 1;
883 }
884
2bd0365f
DS
885 verify_commit_graph_error = 0;
886
887 if (!g->chunk_oid_fanout)
888 graph_report("commit-graph is missing the OID Fanout chunk");
889 if (!g->chunk_oid_lookup)
890 graph_report("commit-graph is missing the OID Lookup chunk");
891 if (!g->chunk_commit_data)
892 graph_report("commit-graph is missing the Commit Data chunk");
893
9bda8467
DS
894 if (verify_commit_graph_error)
895 return verify_commit_graph_error;
896
41df0e30
DS
897 devnull = open("/dev/null", O_WRONLY);
898 f = hashfd(devnull, NULL);
899 hashwrite(f, g->data, g->data_len - g->hash_len);
900 finalize_hashfile(f, checksum.hash, CSUM_CLOSE);
901 if (hashcmp(checksum.hash, g->data + g->data_len - g->hash_len)) {
902 graph_report(_("the commit-graph file has incorrect checksum and is likely corrupt"));
903 verify_commit_graph_error = VERIFY_COMMIT_GRAPH_ERROR_HASH;
904 }
905
9bda8467 906 for (i = 0; i < g->num_commits; i++) {
2e3c0737
DS
907 struct commit *graph_commit;
908
9bda8467
DS
909 hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
910
911 if (i && oidcmp(&prev_oid, &cur_oid) >= 0)
912 graph_report("commit-graph has incorrect OID order: %s then %s",
913 oid_to_hex(&prev_oid),
914 oid_to_hex(&cur_oid));
915
916 oidcpy(&prev_oid, &cur_oid);
917
918 while (cur_oid.hash[0] > cur_fanout_pos) {
919 uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
920
921 if (i != fanout_value)
922 graph_report("commit-graph has incorrect fanout value: fanout[%d] = %u != %u",
923 cur_fanout_pos, fanout_value, i);
924 cur_fanout_pos++;
925 }
2e3c0737 926
82952964 927 graph_commit = lookup_commit(r, &cur_oid);
2e3c0737
DS
928 if (!parse_commit_in_graph_one(g, graph_commit))
929 graph_report("failed to parse %s from commit-graph",
930 oid_to_hex(&cur_oid));
9bda8467
DS
931 }
932
933 while (cur_fanout_pos < 256) {
934 uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
935
936 if (g->num_commits != fanout_value)
937 graph_report("commit-graph has incorrect fanout value: fanout[%d] = %u != %u",
938 cur_fanout_pos, fanout_value, i);
939
940 cur_fanout_pos++;
941 }
942
41df0e30 943 if (verify_commit_graph_error & ~VERIFY_COMMIT_GRAPH_ERROR_HASH)
96af91d4
DS
944 return verify_commit_graph_error;
945
946 for (i = 0; i < g->num_commits; i++) {
2e3c0737 947 struct commit *graph_commit, *odb_commit;
53614b13 948 struct commit_list *graph_parents, *odb_parents;
1373e547 949 uint32_t max_generation = 0;
96af91d4
DS
950
951 hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
952
82952964 953 graph_commit = lookup_commit(r, &cur_oid);
96af91d4
DS
954 odb_commit = (struct commit *)create_object(r, cur_oid.hash, alloc_commit_node(r));
955 if (parse_commit_internal(odb_commit, 0, 0)) {
956 graph_report("failed to parse %s from object database",
957 oid_to_hex(&cur_oid));
958 continue;
959 }
2e3c0737
DS
960
961 if (oidcmp(&get_commit_tree_in_graph_one(g, graph_commit)->object.oid,
962 get_commit_tree_oid(odb_commit)))
963 graph_report("root tree OID for commit %s in commit-graph is %s != %s",
964 oid_to_hex(&cur_oid),
965 oid_to_hex(get_commit_tree_oid(graph_commit)),
966 oid_to_hex(get_commit_tree_oid(odb_commit)));
53614b13
DS
967
968 graph_parents = graph_commit->parents;
969 odb_parents = odb_commit->parents;
970
971 while (graph_parents) {
972 if (odb_parents == NULL) {
973 graph_report("commit-graph parent list for commit %s is too long",
974 oid_to_hex(&cur_oid));
975 break;
976 }
977
978 if (oidcmp(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
979 graph_report("commit-graph parent for %s is %s != %s",
980 oid_to_hex(&cur_oid),
981 oid_to_hex(&graph_parents->item->object.oid),
982 oid_to_hex(&odb_parents->item->object.oid));
983
1373e547
DS
984 if (graph_parents->item->generation > max_generation)
985 max_generation = graph_parents->item->generation;
986
53614b13
DS
987 graph_parents = graph_parents->next;
988 odb_parents = odb_parents->next;
989 }
990
991 if (odb_parents != NULL)
992 graph_report("commit-graph parent list for commit %s terminates early",
993 oid_to_hex(&cur_oid));
1373e547
DS
994
995 if (!graph_commit->generation) {
996 if (generation_zero == GENERATION_NUMBER_EXISTS)
997 graph_report("commit-graph has generation number zero for commit %s, but non-zero elsewhere",
998 oid_to_hex(&cur_oid));
999 generation_zero = GENERATION_ZERO_EXISTS;
1000 } else if (generation_zero == GENERATION_ZERO_EXISTS)
1001 graph_report("commit-graph has non-zero generation number for commit %s, but zero elsewhere",
1002 oid_to_hex(&cur_oid));
1003
1004 if (generation_zero == GENERATION_ZERO_EXISTS)
1005 continue;
1006
1007 /*
1008 * If one of our parents has generation GENERATION_NUMBER_MAX, then
1009 * our generation is also GENERATION_NUMBER_MAX. Decrement to avoid
1010 * extra logic in the following condition.
1011 */
1012 if (max_generation == GENERATION_NUMBER_MAX)
1013 max_generation--;
1014
1015 if (graph_commit->generation != max_generation + 1)
1016 graph_report("commit-graph generation for commit %s is %u != %u",
1017 oid_to_hex(&cur_oid),
1018 graph_commit->generation,
1019 max_generation + 1);
88968ebf
DS
1020
1021 if (graph_commit->date != odb_commit->date)
1022 graph_report("commit date for commit %s in commit-graph is %"PRItime" != %"PRItime,
1023 oid_to_hex(&cur_oid),
1024 graph_commit->date,
1025 odb_commit->date);
96af91d4
DS
1026 }
1027
283e68c7
DS
1028 return verify_commit_graph_error;
1029}