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