commit-graph: merge commit-graph chains
[git/git.git] / commit-graph.c
1 #include "cache.h"
2 #include "config.h"
3 #include "dir.h"
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 "refs.h"
11 #include "revision.h"
12 #include "sha1-lookup.h"
13 #include "commit-graph.h"
14 #include "object-store.h"
15 #include "alloc.h"
16 #include "hashmap.h"
17 #include "replace-object.h"
18 #include "progress.h"
19
20 #define GRAPH_SIGNATURE 0x43475048 /* "CGPH" */
21 #define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
22 #define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
23 #define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
24 #define GRAPH_CHUNKID_EXTRAEDGES 0x45444745 /* "EDGE" */
25 #define GRAPH_CHUNKID_BASE 0x42415345 /* "BASE" */
26
27 #define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16)
28
29 #define GRAPH_VERSION_1 0x1
30 #define GRAPH_VERSION GRAPH_VERSION_1
31
32 #define GRAPH_EXTRA_EDGES_NEEDED 0x80000000
33 #define GRAPH_EDGE_LAST_MASK 0x7fffffff
34 #define GRAPH_PARENT_NONE 0x70000000
35
36 #define GRAPH_LAST_EDGE 0x80000000
37
38 #define GRAPH_HEADER_SIZE 8
39 #define GRAPH_FANOUT_SIZE (4 * 256)
40 #define GRAPH_CHUNKLOOKUP_WIDTH 12
41 #define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
42 + GRAPH_FANOUT_SIZE + the_hash_algo->rawsz)
43
44 char *get_commit_graph_filename(const char *obj_dir)
45 {
46 return xstrfmt("%s/info/commit-graph", obj_dir);
47 }
48
49 static char *get_split_graph_filename(const char *obj_dir,
50 const char *oid_hex)
51 {
52 return xstrfmt("%s/info/commit-graphs/graph-%s.graph",
53 obj_dir,
54 oid_hex);
55 }
56
57 static char *get_chain_filename(const char *obj_dir)
58 {
59 return xstrfmt("%s/info/commit-graphs/commit-graph-chain", obj_dir);
60 }
61
62 static uint8_t oid_version(void)
63 {
64 return 1;
65 }
66
67 static struct commit_graph *alloc_commit_graph(void)
68 {
69 struct commit_graph *g = xcalloc(1, sizeof(*g));
70 g->graph_fd = -1;
71
72 return g;
73 }
74
75 extern int read_replace_refs;
76
77 static int commit_graph_compatible(struct repository *r)
78 {
79 if (!r->gitdir)
80 return 0;
81
82 if (read_replace_refs) {
83 prepare_replace_object(r);
84 if (hashmap_get_size(&r->objects->replace_map->map))
85 return 0;
86 }
87
88 prepare_commit_graft(r);
89 if (r->parsed_objects && r->parsed_objects->grafts_nr)
90 return 0;
91 if (is_repository_shallow(r))
92 return 0;
93
94 return 1;
95 }
96
97 int open_commit_graph(const char *graph_file, int *fd, struct stat *st)
98 {
99 *fd = git_open(graph_file);
100 if (*fd < 0)
101 return 0;
102 if (fstat(*fd, st)) {
103 close(*fd);
104 return 0;
105 }
106 return 1;
107 }
108
109 struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st)
110 {
111 void *graph_map;
112 size_t graph_size;
113 struct commit_graph *ret;
114
115 graph_size = xsize_t(st->st_size);
116
117 if (graph_size < GRAPH_MIN_SIZE) {
118 close(fd);
119 error(_("commit-graph file is too small"));
120 return NULL;
121 }
122 graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
123 ret = parse_commit_graph(graph_map, fd, graph_size);
124
125 if (!ret) {
126 munmap(graph_map, graph_size);
127 close(fd);
128 }
129
130 return ret;
131 }
132
133 static int verify_commit_graph_lite(struct commit_graph *g)
134 {
135 /*
136 * Basic validation shared between parse_commit_graph()
137 * which'll be called every time the graph is used, and the
138 * much more expensive verify_commit_graph() used by
139 * "commit-graph verify".
140 *
141 * There should only be very basic checks here to ensure that
142 * we don't e.g. segfault in fill_commit_in_graph(), but
143 * because this is a very hot codepath nothing that e.g. loops
144 * over g->num_commits, or runs a checksum on the commit-graph
145 * itself.
146 */
147 if (!g->chunk_oid_fanout) {
148 error("commit-graph is missing the OID Fanout chunk");
149 return 1;
150 }
151 if (!g->chunk_oid_lookup) {
152 error("commit-graph is missing the OID Lookup chunk");
153 return 1;
154 }
155 if (!g->chunk_commit_data) {
156 error("commit-graph is missing the Commit Data chunk");
157 return 1;
158 }
159
160 return 0;
161 }
162
163 struct commit_graph *parse_commit_graph(void *graph_map, int fd,
164 size_t graph_size)
165 {
166 const unsigned char *data, *chunk_lookup;
167 uint32_t i;
168 struct commit_graph *graph;
169 uint64_t last_chunk_offset;
170 uint32_t last_chunk_id;
171 uint32_t graph_signature;
172 unsigned char graph_version, hash_version;
173
174 if (!graph_map)
175 return NULL;
176
177 if (graph_size < GRAPH_MIN_SIZE)
178 return NULL;
179
180 data = (const unsigned char *)graph_map;
181
182 graph_signature = get_be32(data);
183 if (graph_signature != GRAPH_SIGNATURE) {
184 error(_("commit-graph signature %X does not match signature %X"),
185 graph_signature, GRAPH_SIGNATURE);
186 return NULL;
187 }
188
189 graph_version = *(unsigned char*)(data + 4);
190 if (graph_version != GRAPH_VERSION) {
191 error(_("commit-graph version %X does not match version %X"),
192 graph_version, GRAPH_VERSION);
193 return NULL;
194 }
195
196 hash_version = *(unsigned char*)(data + 5);
197 if (hash_version != oid_version()) {
198 error(_("commit-graph hash version %X does not match version %X"),
199 hash_version, oid_version());
200 return NULL;
201 }
202
203 graph = alloc_commit_graph();
204
205 graph->hash_len = the_hash_algo->rawsz;
206 graph->num_chunks = *(unsigned char*)(data + 6);
207 graph->graph_fd = fd;
208 graph->data = graph_map;
209 graph->data_len = graph_size;
210
211 last_chunk_id = 0;
212 last_chunk_offset = 8;
213 chunk_lookup = data + 8;
214 for (i = 0; i < graph->num_chunks; i++) {
215 uint32_t chunk_id;
216 uint64_t chunk_offset;
217 int chunk_repeated = 0;
218
219 if (data + graph_size - chunk_lookup <
220 GRAPH_CHUNKLOOKUP_WIDTH) {
221 error(_("commit-graph chunk lookup table entry missing; file may be incomplete"));
222 free(graph);
223 return NULL;
224 }
225
226 chunk_id = get_be32(chunk_lookup + 0);
227 chunk_offset = get_be64(chunk_lookup + 4);
228
229 chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
230
231 if (chunk_offset > graph_size - the_hash_algo->rawsz) {
232 error(_("commit-graph improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32),
233 (uint32_t)chunk_offset);
234 free(graph);
235 return NULL;
236 }
237
238 switch (chunk_id) {
239 case GRAPH_CHUNKID_OIDFANOUT:
240 if (graph->chunk_oid_fanout)
241 chunk_repeated = 1;
242 else
243 graph->chunk_oid_fanout = (uint32_t*)(data + chunk_offset);
244 break;
245
246 case GRAPH_CHUNKID_OIDLOOKUP:
247 if (graph->chunk_oid_lookup)
248 chunk_repeated = 1;
249 else
250 graph->chunk_oid_lookup = data + chunk_offset;
251 break;
252
253 case GRAPH_CHUNKID_DATA:
254 if (graph->chunk_commit_data)
255 chunk_repeated = 1;
256 else
257 graph->chunk_commit_data = data + chunk_offset;
258 break;
259
260 case GRAPH_CHUNKID_EXTRAEDGES:
261 if (graph->chunk_extra_edges)
262 chunk_repeated = 1;
263 else
264 graph->chunk_extra_edges = data + chunk_offset;
265 break;
266
267 case GRAPH_CHUNKID_BASE:
268 if (graph->chunk_base_graphs)
269 chunk_repeated = 1;
270 else
271 graph->chunk_base_graphs = data + chunk_offset;
272 }
273
274 if (chunk_repeated) {
275 error(_("commit-graph chunk id %08x appears multiple times"), chunk_id);
276 free(graph);
277 return NULL;
278 }
279
280 if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP)
281 {
282 graph->num_commits = (chunk_offset - last_chunk_offset)
283 / graph->hash_len;
284 }
285
286 last_chunk_id = chunk_id;
287 last_chunk_offset = chunk_offset;
288 }
289
290 hashcpy(graph->oid.hash, graph->data + graph->data_len - graph->hash_len);
291
292 if (verify_commit_graph_lite(graph))
293 return NULL;
294
295 return graph;
296 }
297
298 static struct commit_graph *load_commit_graph_one(const char *graph_file)
299 {
300
301 struct stat st;
302 int fd;
303 struct commit_graph *g;
304 int open_ok = open_commit_graph(graph_file, &fd, &st);
305
306 if (!open_ok)
307 return NULL;
308
309 g = load_commit_graph_one_fd_st(fd, &st);
310
311 if (g)
312 g->filename = xstrdup(graph_file);
313
314 return g;
315 }
316
317 static struct commit_graph *load_commit_graph_v1(struct repository *r, const char *obj_dir)
318 {
319 char *graph_name = get_commit_graph_filename(obj_dir);
320 struct commit_graph *g = load_commit_graph_one(graph_name);
321 free(graph_name);
322
323 return g;
324 }
325
326 static int add_graph_to_chain(struct commit_graph *g,
327 struct commit_graph *chain,
328 struct object_id *oids,
329 int n)
330 {
331 struct commit_graph *cur_g = chain;
332
333 if (n && !g->chunk_base_graphs) {
334 warning(_("commit-graph has no base graphs chunk"));
335 return 0;
336 }
337
338 while (n) {
339 n--;
340
341 if (!cur_g ||
342 !oideq(&oids[n], &cur_g->oid) ||
343 !hasheq(oids[n].hash, g->chunk_base_graphs + g->hash_len * n)) {
344 warning(_("commit-graph chain does not match"));
345 return 0;
346 }
347
348 cur_g = cur_g->base_graph;
349 }
350
351 g->base_graph = chain;
352
353 if (chain)
354 g->num_commits_in_base = chain->num_commits + chain->num_commits_in_base;
355
356 return 1;
357 }
358
359 static struct commit_graph *load_commit_graph_chain(struct repository *r, const char *obj_dir)
360 {
361 struct commit_graph *graph_chain = NULL;
362 struct strbuf line = STRBUF_INIT;
363 struct stat st;
364 struct object_id *oids;
365 int i = 0, valid = 1, count;
366 char *chain_name = get_chain_filename(obj_dir);
367 FILE *fp;
368 int stat_res;
369
370 fp = fopen(chain_name, "r");
371 stat_res = stat(chain_name, &st);
372 free(chain_name);
373
374 if (!fp ||
375 stat_res ||
376 st.st_size <= the_hash_algo->hexsz)
377 return NULL;
378
379 count = st.st_size / (the_hash_algo->hexsz + 1);
380 oids = xcalloc(count, sizeof(struct object_id));
381
382 for (i = 0; i < count && valid; i++) {
383 char *graph_name;
384 struct commit_graph *g;
385
386 if (strbuf_getline_lf(&line, fp) == EOF)
387 break;
388
389 if (get_oid_hex(line.buf, &oids[i])) {
390 warning(_("invalid commit-graph chain: line '%s' not a hash"),
391 line.buf);
392 valid = 0;
393 break;
394 }
395
396 graph_name = get_split_graph_filename(obj_dir, line.buf);
397 g = load_commit_graph_one(graph_name);
398 free(graph_name);
399
400 if (g && add_graph_to_chain(g, graph_chain, oids, i))
401 graph_chain = g;
402 else
403 valid = 0;
404 }
405
406 free(oids);
407 fclose(fp);
408
409 return graph_chain;
410 }
411
412 static struct commit_graph *read_commit_graph_one(struct repository *r, const char *obj_dir)
413 {
414 struct commit_graph *g = load_commit_graph_v1(r, obj_dir);
415
416 if (!g)
417 g = load_commit_graph_chain(r, obj_dir);
418
419 return g;
420 }
421
422 static void prepare_commit_graph_one(struct repository *r, const char *obj_dir)
423 {
424
425 if (r->objects->commit_graph)
426 return;
427
428 r->objects->commit_graph = read_commit_graph_one(r, obj_dir);
429 }
430
431 /*
432 * Return 1 if commit_graph is non-NULL, and 0 otherwise.
433 *
434 * On the first invocation, this function attemps to load the commit
435 * graph if the_repository is configured to have one.
436 */
437 static int prepare_commit_graph(struct repository *r)
438 {
439 struct object_directory *odb;
440 int config_value;
441
442 if (git_env_bool(GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD, 0))
443 die("dying as requested by the '%s' variable on commit-graph load!",
444 GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD);
445
446 if (r->objects->commit_graph_attempted)
447 return !!r->objects->commit_graph;
448 r->objects->commit_graph_attempted = 1;
449
450 if (!git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
451 (repo_config_get_bool(r, "core.commitgraph", &config_value) ||
452 !config_value))
453 /*
454 * This repository is not configured to use commit graphs, so
455 * do not load one. (But report commit_graph_attempted anyway
456 * so that commit graph loading is not attempted again for this
457 * repository.)
458 */
459 return 0;
460
461 if (!commit_graph_compatible(r))
462 return 0;
463
464 prepare_alt_odb(r);
465 for (odb = r->objects->odb;
466 !r->objects->commit_graph && odb;
467 odb = odb->next)
468 prepare_commit_graph_one(r, odb->path);
469 return !!r->objects->commit_graph;
470 }
471
472 int generation_numbers_enabled(struct repository *r)
473 {
474 uint32_t first_generation;
475 struct commit_graph *g;
476 if (!prepare_commit_graph(r))
477 return 0;
478
479 g = r->objects->commit_graph;
480
481 if (!g->num_commits)
482 return 0;
483
484 first_generation = get_be32(g->chunk_commit_data +
485 g->hash_len + 8) >> 2;
486
487 return !!first_generation;
488 }
489
490 static void close_commit_graph_one(struct commit_graph *g)
491 {
492 if (!g)
493 return;
494
495 close_commit_graph_one(g->base_graph);
496 free_commit_graph(g);
497 }
498
499 void close_commit_graph(struct raw_object_store *o)
500 {
501 close_commit_graph_one(o->commit_graph);
502 o->commit_graph = NULL;
503 }
504
505 static int bsearch_graph(struct commit_graph *g, struct object_id *oid, uint32_t *pos)
506 {
507 return bsearch_hash(oid->hash, g->chunk_oid_fanout,
508 g->chunk_oid_lookup, g->hash_len, pos);
509 }
510
511 static void load_oid_from_graph(struct commit_graph *g,
512 uint32_t pos,
513 struct object_id *oid)
514 {
515 uint32_t lex_index;
516
517 while (g && pos < g->num_commits_in_base)
518 g = g->base_graph;
519
520 if (!g)
521 BUG("NULL commit-graph");
522
523 if (pos >= g->num_commits + g->num_commits_in_base)
524 die(_("invalid commit position. commit-graph is likely corrupt"));
525
526 lex_index = pos - g->num_commits_in_base;
527
528 hashcpy(oid->hash, g->chunk_oid_lookup + g->hash_len * lex_index);
529 }
530
531 static struct commit_list **insert_parent_or_die(struct repository *r,
532 struct commit_graph *g,
533 uint32_t pos,
534 struct commit_list **pptr)
535 {
536 struct commit *c;
537 struct object_id oid;
538
539 if (pos >= g->num_commits + g->num_commits_in_base)
540 die("invalid parent position %"PRIu32, pos);
541
542 load_oid_from_graph(g, pos, &oid);
543 c = lookup_commit(r, &oid);
544 if (!c)
545 die(_("could not find commit %s"), oid_to_hex(&oid));
546 c->graph_pos = pos;
547 return &commit_list_insert(c, pptr)->next;
548 }
549
550 static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
551 {
552 const unsigned char *commit_data;
553 uint32_t lex_index;
554
555 while (pos < g->num_commits_in_base)
556 g = g->base_graph;
557
558 lex_index = pos - g->num_commits_in_base;
559 commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * lex_index;
560 item->graph_pos = pos;
561 item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
562 }
563
564 static int fill_commit_in_graph(struct repository *r,
565 struct commit *item,
566 struct commit_graph *g, uint32_t pos)
567 {
568 uint32_t edge_value;
569 uint32_t *parent_data_ptr;
570 uint64_t date_low, date_high;
571 struct commit_list **pptr;
572 const unsigned char *commit_data;
573 uint32_t lex_index;
574
575 while (pos < g->num_commits_in_base)
576 g = g->base_graph;
577
578 if (pos >= g->num_commits + g->num_commits_in_base)
579 die(_("invalid commit position. commit-graph is likely corrupt"));
580
581 /*
582 * Store the "full" position, but then use the
583 * "local" position for the rest of the calculation.
584 */
585 item->graph_pos = pos;
586 lex_index = pos - g->num_commits_in_base;
587
588 commit_data = g->chunk_commit_data + (g->hash_len + 16) * lex_index;
589
590 item->object.parsed = 1;
591
592 item->maybe_tree = NULL;
593
594 date_high = get_be32(commit_data + g->hash_len + 8) & 0x3;
595 date_low = get_be32(commit_data + g->hash_len + 12);
596 item->date = (timestamp_t)((date_high << 32) | date_low);
597
598 item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
599
600 pptr = &item->parents;
601
602 edge_value = get_be32(commit_data + g->hash_len);
603 if (edge_value == GRAPH_PARENT_NONE)
604 return 1;
605 pptr = insert_parent_or_die(r, g, edge_value, pptr);
606
607 edge_value = get_be32(commit_data + g->hash_len + 4);
608 if (edge_value == GRAPH_PARENT_NONE)
609 return 1;
610 if (!(edge_value & GRAPH_EXTRA_EDGES_NEEDED)) {
611 pptr = insert_parent_or_die(r, g, edge_value, pptr);
612 return 1;
613 }
614
615 parent_data_ptr = (uint32_t*)(g->chunk_extra_edges +
616 4 * (uint64_t)(edge_value & GRAPH_EDGE_LAST_MASK));
617 do {
618 edge_value = get_be32(parent_data_ptr);
619 pptr = insert_parent_or_die(r, g,
620 edge_value & GRAPH_EDGE_LAST_MASK,
621 pptr);
622 parent_data_ptr++;
623 } while (!(edge_value & GRAPH_LAST_EDGE));
624
625 return 1;
626 }
627
628 static int find_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t *pos)
629 {
630 if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
631 *pos = item->graph_pos;
632 return 1;
633 } else {
634 struct commit_graph *cur_g = g;
635 uint32_t lex_index;
636
637 while (cur_g && !bsearch_graph(cur_g, &(item->object.oid), &lex_index))
638 cur_g = cur_g->base_graph;
639
640 if (cur_g) {
641 *pos = lex_index + cur_g->num_commits_in_base;
642 return 1;
643 }
644
645 return 0;
646 }
647 }
648
649 static int parse_commit_in_graph_one(struct repository *r,
650 struct commit_graph *g,
651 struct commit *item)
652 {
653 uint32_t pos;
654
655 if (item->object.parsed)
656 return 1;
657
658 if (find_commit_in_graph(item, g, &pos))
659 return fill_commit_in_graph(r, item, g, pos);
660
661 return 0;
662 }
663
664 int parse_commit_in_graph(struct repository *r, struct commit *item)
665 {
666 if (!prepare_commit_graph(r))
667 return 0;
668 return parse_commit_in_graph_one(r, r->objects->commit_graph, item);
669 }
670
671 void load_commit_graph_info(struct repository *r, struct commit *item)
672 {
673 uint32_t pos;
674 if (!prepare_commit_graph(r))
675 return;
676 if (find_commit_in_graph(item, r->objects->commit_graph, &pos))
677 fill_commit_graph_info(item, r->objects->commit_graph, pos);
678 }
679
680 static struct tree *load_tree_for_commit(struct repository *r,
681 struct commit_graph *g,
682 struct commit *c)
683 {
684 struct object_id oid;
685 const unsigned char *commit_data;
686
687 while (c->graph_pos < g->num_commits_in_base)
688 g = g->base_graph;
689
690 commit_data = g->chunk_commit_data +
691 GRAPH_DATA_WIDTH * (c->graph_pos - g->num_commits_in_base);
692
693 hashcpy(oid.hash, commit_data);
694 c->maybe_tree = lookup_tree(r, &oid);
695
696 return c->maybe_tree;
697 }
698
699 static struct tree *get_commit_tree_in_graph_one(struct repository *r,
700 struct commit_graph *g,
701 const struct commit *c)
702 {
703 if (c->maybe_tree)
704 return c->maybe_tree;
705 if (c->graph_pos == COMMIT_NOT_FROM_GRAPH)
706 BUG("get_commit_tree_in_graph_one called from non-commit-graph commit");
707
708 return load_tree_for_commit(r, g, (struct commit *)c);
709 }
710
711 struct tree *get_commit_tree_in_graph(struct repository *r, const struct commit *c)
712 {
713 return get_commit_tree_in_graph_one(r, r->objects->commit_graph, c);
714 }
715
716 struct packed_commit_list {
717 struct commit **list;
718 int nr;
719 int alloc;
720 };
721
722 struct packed_oid_list {
723 struct object_id *list;
724 int nr;
725 int alloc;
726 };
727
728 struct write_commit_graph_context {
729 struct repository *r;
730 const char *obj_dir;
731 char *graph_name;
732 struct packed_oid_list oids;
733 struct packed_commit_list commits;
734 int num_extra_edges;
735 unsigned long approx_nr_objects;
736 struct progress *progress;
737 int progress_done;
738 uint64_t progress_cnt;
739
740 char *base_graph_name;
741 int num_commit_graphs_before;
742 int num_commit_graphs_after;
743 char **commit_graph_filenames_before;
744 char **commit_graph_filenames_after;
745 char **commit_graph_hash_after;
746 uint32_t new_num_commits_in_base;
747 struct commit_graph *new_base_graph;
748
749 unsigned append:1,
750 report_progress:1,
751 split:1;
752 };
753
754 static void write_graph_chunk_fanout(struct hashfile *f,
755 struct write_commit_graph_context *ctx)
756 {
757 int i, count = 0;
758 struct commit **list = ctx->commits.list;
759
760 /*
761 * Write the first-level table (the list is sorted,
762 * but we use a 256-entry lookup to be able to avoid
763 * having to do eight extra binary search iterations).
764 */
765 for (i = 0; i < 256; i++) {
766 while (count < ctx->commits.nr) {
767 if ((*list)->object.oid.hash[0] != i)
768 break;
769 display_progress(ctx->progress, ++ctx->progress_cnt);
770 count++;
771 list++;
772 }
773
774 hashwrite_be32(f, count);
775 }
776 }
777
778 static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
779 struct write_commit_graph_context *ctx)
780 {
781 struct commit **list = ctx->commits.list;
782 int count;
783 for (count = 0; count < ctx->commits.nr; count++, list++) {
784 display_progress(ctx->progress, ++ctx->progress_cnt);
785 hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
786 }
787 }
788
789 static const unsigned char *commit_to_sha1(size_t index, void *table)
790 {
791 struct commit **commits = table;
792 return commits[index]->object.oid.hash;
793 }
794
795 static void write_graph_chunk_data(struct hashfile *f, int hash_len,
796 struct write_commit_graph_context *ctx)
797 {
798 struct commit **list = ctx->commits.list;
799 struct commit **last = ctx->commits.list + ctx->commits.nr;
800 uint32_t num_extra_edges = 0;
801
802 while (list < last) {
803 struct commit_list *parent;
804 int edge_value;
805 uint32_t packedDate[2];
806 display_progress(ctx->progress, ++ctx->progress_cnt);
807
808 parse_commit_no_graph(*list);
809 hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
810
811 parent = (*list)->parents;
812
813 if (!parent)
814 edge_value = GRAPH_PARENT_NONE;
815 else {
816 edge_value = sha1_pos(parent->item->object.oid.hash,
817 ctx->commits.list,
818 ctx->commits.nr,
819 commit_to_sha1);
820
821 if (edge_value >= 0)
822 edge_value += ctx->new_num_commits_in_base;
823 else {
824 uint32_t pos;
825 if (find_commit_in_graph(parent->item,
826 ctx->new_base_graph,
827 &pos))
828 edge_value = pos;
829 }
830
831 if (edge_value < 0)
832 BUG("missing parent %s for commit %s",
833 oid_to_hex(&parent->item->object.oid),
834 oid_to_hex(&(*list)->object.oid));
835 }
836
837 hashwrite_be32(f, edge_value);
838
839 if (parent)
840 parent = parent->next;
841
842 if (!parent)
843 edge_value = GRAPH_PARENT_NONE;
844 else if (parent->next)
845 edge_value = GRAPH_EXTRA_EDGES_NEEDED | num_extra_edges;
846 else {
847 edge_value = sha1_pos(parent->item->object.oid.hash,
848 ctx->commits.list,
849 ctx->commits.nr,
850 commit_to_sha1);
851
852 if (edge_value >= 0)
853 edge_value += ctx->new_num_commits_in_base;
854 else {
855 uint32_t pos;
856 if (find_commit_in_graph(parent->item,
857 ctx->new_base_graph,
858 &pos))
859 edge_value = pos;
860 }
861
862 if (edge_value < 0)
863 BUG("missing parent %s for commit %s",
864 oid_to_hex(&parent->item->object.oid),
865 oid_to_hex(&(*list)->object.oid));
866 }
867
868 hashwrite_be32(f, edge_value);
869
870 if (edge_value & GRAPH_EXTRA_EDGES_NEEDED) {
871 do {
872 num_extra_edges++;
873 parent = parent->next;
874 } while (parent);
875 }
876
877 if (sizeof((*list)->date) > 4)
878 packedDate[0] = htonl(((*list)->date >> 32) & 0x3);
879 else
880 packedDate[0] = 0;
881
882 packedDate[0] |= htonl((*list)->generation << 2);
883
884 packedDate[1] = htonl((*list)->date);
885 hashwrite(f, packedDate, 8);
886
887 list++;
888 }
889 }
890
891 static void write_graph_chunk_extra_edges(struct hashfile *f,
892 struct write_commit_graph_context *ctx)
893 {
894 struct commit **list = ctx->commits.list;
895 struct commit **last = ctx->commits.list + ctx->commits.nr;
896 struct commit_list *parent;
897
898 while (list < last) {
899 int num_parents = 0;
900
901 display_progress(ctx->progress, ++ctx->progress_cnt);
902
903 for (parent = (*list)->parents; num_parents < 3 && parent;
904 parent = parent->next)
905 num_parents++;
906
907 if (num_parents <= 2) {
908 list++;
909 continue;
910 }
911
912 /* Since num_parents > 2, this initializer is safe. */
913 for (parent = (*list)->parents->next; parent; parent = parent->next) {
914 int edge_value = sha1_pos(parent->item->object.oid.hash,
915 ctx->commits.list,
916 ctx->commits.nr,
917 commit_to_sha1);
918
919 if (edge_value >= 0)
920 edge_value += ctx->new_num_commits_in_base;
921 else {
922 uint32_t pos;
923 if (find_commit_in_graph(parent->item,
924 ctx->new_base_graph,
925 &pos))
926 edge_value = pos;
927 }
928
929 if (edge_value < 0)
930 BUG("missing parent %s for commit %s",
931 oid_to_hex(&parent->item->object.oid),
932 oid_to_hex(&(*list)->object.oid));
933 else if (!parent->next)
934 edge_value |= GRAPH_LAST_EDGE;
935
936 hashwrite_be32(f, edge_value);
937 }
938
939 list++;
940 }
941 }
942
943 static int oid_compare(const void *_a, const void *_b)
944 {
945 const struct object_id *a = (const struct object_id *)_a;
946 const struct object_id *b = (const struct object_id *)_b;
947 return oidcmp(a, b);
948 }
949
950 static int add_packed_commits(const struct object_id *oid,
951 struct packed_git *pack,
952 uint32_t pos,
953 void *data)
954 {
955 struct write_commit_graph_context *ctx = (struct write_commit_graph_context*)data;
956 enum object_type type;
957 off_t offset = nth_packed_object_offset(pack, pos);
958 struct object_info oi = OBJECT_INFO_INIT;
959
960 if (ctx->progress)
961 display_progress(ctx->progress, ++ctx->progress_done);
962
963 oi.typep = &type;
964 if (packed_object_info(ctx->r, pack, offset, &oi) < 0)
965 die(_("unable to get type of object %s"), oid_to_hex(oid));
966
967 if (type != OBJ_COMMIT)
968 return 0;
969
970 ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
971 oidcpy(&(ctx->oids.list[ctx->oids.nr]), oid);
972 ctx->oids.nr++;
973
974 return 0;
975 }
976
977 static void add_missing_parents(struct write_commit_graph_context *ctx, struct commit *commit)
978 {
979 struct commit_list *parent;
980 for (parent = commit->parents; parent; parent = parent->next) {
981 if (!(parent->item->object.flags & UNINTERESTING)) {
982 ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
983 oidcpy(&ctx->oids.list[ctx->oids.nr], &(parent->item->object.oid));
984 ctx->oids.nr++;
985 parent->item->object.flags |= UNINTERESTING;
986 }
987 }
988 }
989
990 static void close_reachable(struct write_commit_graph_context *ctx)
991 {
992 int i;
993 struct commit *commit;
994
995 if (ctx->report_progress)
996 ctx->progress = start_delayed_progress(
997 _("Loading known commits in commit graph"),
998 ctx->oids.nr);
999 for (i = 0; i < ctx->oids.nr; i++) {
1000 display_progress(ctx->progress, i + 1);
1001 commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
1002 if (commit)
1003 commit->object.flags |= UNINTERESTING;
1004 }
1005 stop_progress(&ctx->progress);
1006
1007 /*
1008 * As this loop runs, ctx->oids.nr may grow, but not more
1009 * than the number of missing commits in the reachable
1010 * closure.
1011 */
1012 if (ctx->report_progress)
1013 ctx->progress = start_delayed_progress(
1014 _("Expanding reachable commits in commit graph"),
1015 ctx->oids.nr);
1016 for (i = 0; i < ctx->oids.nr; i++) {
1017 display_progress(ctx->progress, i + 1);
1018 commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
1019
1020 if (!commit)
1021 continue;
1022 if (ctx->split) {
1023 if (!parse_commit(commit) &&
1024 commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
1025 add_missing_parents(ctx, commit);
1026 } else if (!parse_commit_no_graph(commit))
1027 add_missing_parents(ctx, commit);
1028 }
1029 stop_progress(&ctx->progress);
1030
1031 if (ctx->report_progress)
1032 ctx->progress = start_delayed_progress(
1033 _("Clearing commit marks in commit graph"),
1034 ctx->oids.nr);
1035 for (i = 0; i < ctx->oids.nr; i++) {
1036 display_progress(ctx->progress, i + 1);
1037 commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
1038
1039 if (commit)
1040 commit->object.flags &= ~UNINTERESTING;
1041 }
1042 stop_progress(&ctx->progress);
1043 }
1044
1045 static void compute_generation_numbers(struct write_commit_graph_context *ctx)
1046 {
1047 int i;
1048 struct commit_list *list = NULL;
1049
1050 if (ctx->report_progress)
1051 ctx->progress = start_progress(
1052 _("Computing commit graph generation numbers"),
1053 ctx->commits.nr);
1054 for (i = 0; i < ctx->commits.nr; i++) {
1055 display_progress(ctx->progress, i + 1);
1056 if (ctx->commits.list[i]->generation != GENERATION_NUMBER_INFINITY &&
1057 ctx->commits.list[i]->generation != GENERATION_NUMBER_ZERO)
1058 continue;
1059
1060 commit_list_insert(ctx->commits.list[i], &list);
1061 while (list) {
1062 struct commit *current = list->item;
1063 struct commit_list *parent;
1064 int all_parents_computed = 1;
1065 uint32_t max_generation = 0;
1066
1067 for (parent = current->parents; parent; parent = parent->next) {
1068 if (parent->item->generation == GENERATION_NUMBER_INFINITY ||
1069 parent->item->generation == GENERATION_NUMBER_ZERO) {
1070 all_parents_computed = 0;
1071 commit_list_insert(parent->item, &list);
1072 break;
1073 } else if (parent->item->generation > max_generation) {
1074 max_generation = parent->item->generation;
1075 }
1076 }
1077
1078 if (all_parents_computed) {
1079 current->generation = max_generation + 1;
1080 pop_commit(&list);
1081
1082 if (current->generation > GENERATION_NUMBER_MAX)
1083 current->generation = GENERATION_NUMBER_MAX;
1084 }
1085 }
1086 }
1087 stop_progress(&ctx->progress);
1088 }
1089
1090 static int add_ref_to_list(const char *refname,
1091 const struct object_id *oid,
1092 int flags, void *cb_data)
1093 {
1094 struct string_list *list = (struct string_list *)cb_data;
1095
1096 string_list_append(list, oid_to_hex(oid));
1097 return 0;
1098 }
1099
1100 int write_commit_graph_reachable(const char *obj_dir, unsigned int flags)
1101 {
1102 struct string_list list = STRING_LIST_INIT_DUP;
1103 int result;
1104
1105 for_each_ref(add_ref_to_list, &list);
1106 result = write_commit_graph(obj_dir, NULL, &list,
1107 flags);
1108
1109 string_list_clear(&list, 0);
1110 return result;
1111 }
1112
1113 static int fill_oids_from_packs(struct write_commit_graph_context *ctx,
1114 struct string_list *pack_indexes)
1115 {
1116 uint32_t i;
1117 struct strbuf progress_title = STRBUF_INIT;
1118 struct strbuf packname = STRBUF_INIT;
1119 int dirlen;
1120
1121 strbuf_addf(&packname, "%s/pack/", ctx->obj_dir);
1122 dirlen = packname.len;
1123 if (ctx->report_progress) {
1124 strbuf_addf(&progress_title,
1125 Q_("Finding commits for commit graph in %d pack",
1126 "Finding commits for commit graph in %d packs",
1127 pack_indexes->nr),
1128 pack_indexes->nr);
1129 ctx->progress = start_delayed_progress(progress_title.buf, 0);
1130 ctx->progress_done = 0;
1131 }
1132 for (i = 0; i < pack_indexes->nr; i++) {
1133 struct packed_git *p;
1134 strbuf_setlen(&packname, dirlen);
1135 strbuf_addstr(&packname, pack_indexes->items[i].string);
1136 p = add_packed_git(packname.buf, packname.len, 1);
1137 if (!p) {
1138 error(_("error adding pack %s"), packname.buf);
1139 return -1;
1140 }
1141 if (open_pack_index(p)) {
1142 error(_("error opening index for %s"), packname.buf);
1143 return -1;
1144 }
1145 for_each_object_in_pack(p, add_packed_commits, ctx,
1146 FOR_EACH_OBJECT_PACK_ORDER);
1147 close_pack(p);
1148 free(p);
1149 }
1150
1151 stop_progress(&ctx->progress);
1152 strbuf_reset(&progress_title);
1153 strbuf_release(&packname);
1154
1155 return 0;
1156 }
1157
1158 static void fill_oids_from_commit_hex(struct write_commit_graph_context *ctx,
1159 struct string_list *commit_hex)
1160 {
1161 uint32_t i;
1162 struct strbuf progress_title = STRBUF_INIT;
1163
1164 if (ctx->report_progress) {
1165 strbuf_addf(&progress_title,
1166 Q_("Finding commits for commit graph from %d ref",
1167 "Finding commits for commit graph from %d refs",
1168 commit_hex->nr),
1169 commit_hex->nr);
1170 ctx->progress = start_delayed_progress(
1171 progress_title.buf,
1172 commit_hex->nr);
1173 }
1174 for (i = 0; i < commit_hex->nr; i++) {
1175 const char *end;
1176 struct object_id oid;
1177 struct commit *result;
1178
1179 display_progress(ctx->progress, i + 1);
1180 if (commit_hex->items[i].string &&
1181 parse_oid_hex(commit_hex->items[i].string, &oid, &end))
1182 continue;
1183
1184 result = lookup_commit_reference_gently(ctx->r, &oid, 1);
1185
1186 if (result) {
1187 ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
1188 oidcpy(&ctx->oids.list[ctx->oids.nr], &(result->object.oid));
1189 ctx->oids.nr++;
1190 }
1191 }
1192 stop_progress(&ctx->progress);
1193 strbuf_release(&progress_title);
1194 }
1195
1196 static void fill_oids_from_all_packs(struct write_commit_graph_context *ctx)
1197 {
1198 if (ctx->report_progress)
1199 ctx->progress = start_delayed_progress(
1200 _("Finding commits for commit graph among packed objects"),
1201 ctx->approx_nr_objects);
1202 for_each_packed_object(add_packed_commits, ctx,
1203 FOR_EACH_OBJECT_PACK_ORDER);
1204 if (ctx->progress_done < ctx->approx_nr_objects)
1205 display_progress(ctx->progress, ctx->approx_nr_objects);
1206 stop_progress(&ctx->progress);
1207 }
1208
1209 static uint32_t count_distinct_commits(struct write_commit_graph_context *ctx)
1210 {
1211 uint32_t i, count_distinct = 1;
1212
1213 if (ctx->report_progress)
1214 ctx->progress = start_delayed_progress(
1215 _("Counting distinct commits in commit graph"),
1216 ctx->oids.nr);
1217 display_progress(ctx->progress, 0); /* TODO: Measure QSORT() progress */
1218 QSORT(ctx->oids.list, ctx->oids.nr, oid_compare);
1219
1220 for (i = 1; i < ctx->oids.nr; i++) {
1221 display_progress(ctx->progress, i + 1);
1222 if (!oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i])) {
1223 if (ctx->split) {
1224 struct commit *c = lookup_commit(ctx->r, &ctx->oids.list[i]);
1225
1226 if (!c || c->graph_pos != COMMIT_NOT_FROM_GRAPH)
1227 continue;
1228 }
1229
1230 count_distinct++;
1231 }
1232 }
1233 stop_progress(&ctx->progress);
1234
1235 return count_distinct;
1236 }
1237
1238 static void copy_oids_to_commits(struct write_commit_graph_context *ctx)
1239 {
1240 uint32_t i;
1241 struct commit_list *parent;
1242
1243 ctx->num_extra_edges = 0;
1244 if (ctx->report_progress)
1245 ctx->progress = start_delayed_progress(
1246 _("Finding extra edges in commit graph"),
1247 ctx->oids.nr);
1248 for (i = 0; i < ctx->oids.nr; i++) {
1249 int num_parents = 0;
1250 display_progress(ctx->progress, i + 1);
1251 if (i > 0 && oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i]))
1252 continue;
1253
1254 ALLOC_GROW(ctx->commits.list, ctx->commits.nr + 1, ctx->commits.alloc);
1255 ctx->commits.list[ctx->commits.nr] = lookup_commit(ctx->r, &ctx->oids.list[i]);
1256
1257 if (ctx->split &&
1258 ctx->commits.list[ctx->commits.nr]->graph_pos != COMMIT_NOT_FROM_GRAPH)
1259 continue;
1260
1261 parse_commit_no_graph(ctx->commits.list[ctx->commits.nr]);
1262
1263 for (parent = ctx->commits.list[ctx->commits.nr]->parents;
1264 parent; parent = parent->next)
1265 num_parents++;
1266
1267 if (num_parents > 2)
1268 ctx->num_extra_edges += num_parents - 1;
1269
1270 ctx->commits.nr++;
1271 }
1272 stop_progress(&ctx->progress);
1273 }
1274
1275 static int write_graph_chunk_base_1(struct hashfile *f,
1276 struct commit_graph *g)
1277 {
1278 int num = 0;
1279
1280 if (!g)
1281 return 0;
1282
1283 num = write_graph_chunk_base_1(f, g->base_graph);
1284 hashwrite(f, g->oid.hash, the_hash_algo->rawsz);
1285 return num + 1;
1286 }
1287
1288 static int write_graph_chunk_base(struct hashfile *f,
1289 struct write_commit_graph_context *ctx)
1290 {
1291 int num = write_graph_chunk_base_1(f, ctx->new_base_graph);
1292
1293 if (num != ctx->num_commit_graphs_after - 1) {
1294 error(_("failed to write correct number of base graph ids"));
1295 return -1;
1296 }
1297
1298 return 0;
1299 }
1300
1301 static int write_commit_graph_file(struct write_commit_graph_context *ctx)
1302 {
1303 uint32_t i;
1304 int fd;
1305 struct hashfile *f;
1306 struct lock_file lk = LOCK_INIT;
1307 uint32_t chunk_ids[6];
1308 uint64_t chunk_offsets[6];
1309 const unsigned hashsz = the_hash_algo->rawsz;
1310 struct strbuf progress_title = STRBUF_INIT;
1311 int num_chunks = 3;
1312 struct object_id file_hash;
1313
1314 if (ctx->split) {
1315 struct strbuf tmp_file = STRBUF_INIT;
1316
1317 strbuf_addf(&tmp_file,
1318 "%s/info/commit-graphs/tmp_graph_XXXXXX",
1319 ctx->obj_dir);
1320 ctx->graph_name = strbuf_detach(&tmp_file, NULL);
1321 } else {
1322 ctx->graph_name = get_commit_graph_filename(ctx->obj_dir);
1323 }
1324
1325 if (safe_create_leading_directories(ctx->graph_name)) {
1326 UNLEAK(ctx->graph_name);
1327 error(_("unable to create leading directories of %s"),
1328 ctx->graph_name);
1329 return -1;
1330 }
1331
1332 if (ctx->split) {
1333 char *lock_name = get_chain_filename(ctx->obj_dir);
1334
1335 hold_lock_file_for_update(&lk, lock_name, LOCK_DIE_ON_ERROR);
1336
1337 fd = git_mkstemp_mode(ctx->graph_name, 0444);
1338 if (fd < 0) {
1339 error(_("unable to create '%s'"), ctx->graph_name);
1340 return -1;
1341 }
1342
1343 f = hashfd(fd, ctx->graph_name);
1344 } else {
1345 hold_lock_file_for_update(&lk, ctx->graph_name, LOCK_DIE_ON_ERROR);
1346 fd = lk.tempfile->fd;
1347 f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
1348 }
1349
1350 chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
1351 chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
1352 chunk_ids[2] = GRAPH_CHUNKID_DATA;
1353 if (ctx->num_extra_edges) {
1354 chunk_ids[num_chunks] = GRAPH_CHUNKID_EXTRAEDGES;
1355 num_chunks++;
1356 }
1357 if (ctx->num_commit_graphs_after > 1) {
1358 chunk_ids[num_chunks] = GRAPH_CHUNKID_BASE;
1359 num_chunks++;
1360 }
1361
1362 chunk_ids[num_chunks] = 0;
1363
1364 chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
1365 chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
1366 chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
1367 chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;
1368
1369 num_chunks = 3;
1370 if (ctx->num_extra_edges) {
1371 chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
1372 4 * ctx->num_extra_edges;
1373 num_chunks++;
1374 }
1375 if (ctx->num_commit_graphs_after > 1) {
1376 chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
1377 hashsz * (ctx->num_commit_graphs_after - 1);
1378 num_chunks++;
1379 }
1380
1381 hashwrite_be32(f, GRAPH_SIGNATURE);
1382
1383 hashwrite_u8(f, GRAPH_VERSION);
1384 hashwrite_u8(f, oid_version());
1385 hashwrite_u8(f, num_chunks);
1386 hashwrite_u8(f, ctx->num_commit_graphs_after - 1);
1387
1388 for (i = 0; i <= num_chunks; i++) {
1389 uint32_t chunk_write[3];
1390
1391 chunk_write[0] = htonl(chunk_ids[i]);
1392 chunk_write[1] = htonl(chunk_offsets[i] >> 32);
1393 chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
1394 hashwrite(f, chunk_write, 12);
1395 }
1396
1397 if (ctx->report_progress) {
1398 strbuf_addf(&progress_title,
1399 Q_("Writing out commit graph in %d pass",
1400 "Writing out commit graph in %d passes",
1401 num_chunks),
1402 num_chunks);
1403 ctx->progress = start_delayed_progress(
1404 progress_title.buf,
1405 num_chunks * ctx->commits.nr);
1406 }
1407 write_graph_chunk_fanout(f, ctx);
1408 write_graph_chunk_oids(f, hashsz, ctx);
1409 write_graph_chunk_data(f, hashsz, ctx);
1410 if (ctx->num_extra_edges)
1411 write_graph_chunk_extra_edges(f, ctx);
1412 if (ctx->num_commit_graphs_after > 1 &&
1413 write_graph_chunk_base(f, ctx)) {
1414 return -1;
1415 }
1416 stop_progress(&ctx->progress);
1417 strbuf_release(&progress_title);
1418
1419 if (ctx->split && ctx->base_graph_name && ctx->num_commit_graphs_after > 1) {
1420 char *new_base_hash = xstrdup(oid_to_hex(&ctx->new_base_graph->oid));
1421 char *new_base_name = get_split_graph_filename(ctx->obj_dir, new_base_hash);
1422
1423 free(ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2]);
1424 free(ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2]);
1425 ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2] = new_base_name;
1426 ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2] = new_base_hash;
1427 }
1428
1429 close_commit_graph(ctx->r->objects);
1430 finalize_hashfile(f, file_hash.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
1431
1432 if (ctx->split) {
1433 FILE *chainf = fdopen_lock_file(&lk, "w");
1434 char *final_graph_name;
1435 int result;
1436
1437 close(fd);
1438
1439 if (!chainf) {
1440 error(_("unable to open commit-graph chain file"));
1441 return -1;
1442 }
1443
1444 if (ctx->base_graph_name) {
1445 const char *dest = ctx->commit_graph_filenames_after[
1446 ctx->num_commit_graphs_after - 2];
1447
1448 if (strcmp(ctx->base_graph_name, dest)) {
1449 result = rename(ctx->base_graph_name, dest);
1450
1451 if (result) {
1452 error(_("failed to rename base commit-graph file"));
1453 return -1;
1454 }
1455 }
1456 } else {
1457 char *graph_name = get_commit_graph_filename(ctx->obj_dir);
1458 unlink(graph_name);
1459 }
1460
1461 ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1] = xstrdup(oid_to_hex(&file_hash));
1462 final_graph_name = get_split_graph_filename(ctx->obj_dir,
1463 ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1]);
1464 ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 1] = final_graph_name;
1465
1466 result = rename(ctx->graph_name, final_graph_name);
1467
1468 for (i = 0; i < ctx->num_commit_graphs_after; i++)
1469 fprintf(lk.tempfile->fp, "%s\n", ctx->commit_graph_hash_after[i]);
1470
1471 if (result) {
1472 error(_("failed to rename temporary commit-graph file"));
1473 return -1;
1474 }
1475 }
1476
1477 commit_lock_file(&lk);
1478
1479 return 0;
1480 }
1481
1482 static int split_strategy_max_commits = 64000;
1483 static float split_strategy_size_mult = 2.0f;
1484
1485 static void split_graph_merge_strategy(struct write_commit_graph_context *ctx)
1486 {
1487 struct commit_graph *g = ctx->r->objects->commit_graph;
1488 uint32_t num_commits = ctx->commits.nr;
1489 uint32_t i;
1490
1491 g = ctx->r->objects->commit_graph;
1492 ctx->num_commit_graphs_after = ctx->num_commit_graphs_before + 1;
1493
1494 while (g && (g->num_commits <= split_strategy_size_mult * num_commits ||
1495 num_commits > split_strategy_max_commits)) {
1496 num_commits += g->num_commits;
1497 g = g->base_graph;
1498
1499 ctx->num_commit_graphs_after--;
1500 }
1501
1502 ctx->new_base_graph = g;
1503
1504 ALLOC_ARRAY(ctx->commit_graph_filenames_after, ctx->num_commit_graphs_after);
1505 ALLOC_ARRAY(ctx->commit_graph_hash_after, ctx->num_commit_graphs_after);
1506
1507 for (i = 0; i < ctx->num_commit_graphs_after &&
1508 i < ctx->num_commit_graphs_before; i++)
1509 ctx->commit_graph_filenames_after[i] = xstrdup(ctx->commit_graph_filenames_before[i]);
1510
1511 i = ctx->num_commit_graphs_before - 1;
1512 g = ctx->r->objects->commit_graph;
1513
1514 while (g) {
1515 if (i < ctx->num_commit_graphs_after)
1516 ctx->commit_graph_hash_after[i] = xstrdup(oid_to_hex(&g->oid));
1517
1518 i--;
1519 g = g->base_graph;
1520 }
1521 }
1522
1523 static void merge_commit_graph(struct write_commit_graph_context *ctx,
1524 struct commit_graph *g)
1525 {
1526 uint32_t i;
1527 uint32_t offset = g->num_commits_in_base;
1528
1529 ALLOC_GROW(ctx->commits.list, ctx->commits.nr + g->num_commits, ctx->commits.alloc);
1530
1531 for (i = 0; i < g->num_commits; i++) {
1532 struct object_id oid;
1533 struct commit *result;
1534
1535 display_progress(ctx->progress, i + 1);
1536
1537 load_oid_from_graph(g, i + offset, &oid);
1538
1539 /* only add commits if they still exist in the repo */
1540 result = lookup_commit_reference_gently(ctx->r, &oid, 1);
1541
1542 if (result) {
1543 ctx->commits.list[ctx->commits.nr] = result;
1544 ctx->commits.nr++;
1545 }
1546 }
1547 }
1548
1549 static int commit_compare(const void *_a, const void *_b)
1550 {
1551 const struct commit *a = *(const struct commit **)_a;
1552 const struct commit *b = *(const struct commit **)_b;
1553 return oidcmp(&a->object.oid, &b->object.oid);
1554 }
1555
1556 static void sort_and_scan_merged_commits(struct write_commit_graph_context *ctx)
1557 {
1558 uint32_t i, num_parents;
1559 struct commit_list *parent;
1560
1561 if (ctx->report_progress)
1562 ctx->progress = start_delayed_progress(
1563 _("Scanning merged commits"),
1564 ctx->commits.nr);
1565
1566 QSORT(ctx->commits.list, ctx->commits.nr, commit_compare);
1567
1568 ctx->num_extra_edges = 0;
1569 for (i = 0; i < ctx->commits.nr; i++) {
1570 display_progress(ctx->progress, i);
1571
1572 if (i && oideq(&ctx->commits.list[i - 1]->object.oid,
1573 &ctx->commits.list[i]->object.oid)) {
1574 die(_("unexpected duplicate commit id %s"),
1575 oid_to_hex(&ctx->commits.list[i]->object.oid));
1576 } else {
1577 num_parents = 0;
1578 for (parent = ctx->commits.list[i]->parents; parent; parent = parent->next)
1579 num_parents++;
1580
1581 if (num_parents > 2)
1582 ctx->num_extra_edges += num_parents - 2;
1583 }
1584 }
1585
1586 stop_progress(&ctx->progress);
1587 }
1588
1589 static void merge_commit_graphs(struct write_commit_graph_context *ctx)
1590 {
1591 struct commit_graph *g = ctx->r->objects->commit_graph;
1592 uint32_t current_graph_number = ctx->num_commit_graphs_before;
1593 struct strbuf progress_title = STRBUF_INIT;
1594
1595 while (g && current_graph_number >= ctx->num_commit_graphs_after) {
1596 current_graph_number--;
1597
1598 if (ctx->report_progress) {
1599 strbuf_addstr(&progress_title, _("Merging commit-graph"));
1600 ctx->progress = start_delayed_progress(progress_title.buf, 0);
1601 }
1602
1603 merge_commit_graph(ctx, g);
1604 stop_progress(&ctx->progress);
1605 strbuf_release(&progress_title);
1606
1607 g = g->base_graph;
1608 }
1609
1610 if (g) {
1611 ctx->new_base_graph = g;
1612 ctx->new_num_commits_in_base = g->num_commits + g->num_commits_in_base;
1613 }
1614
1615 if (ctx->new_base_graph)
1616 ctx->base_graph_name = xstrdup(ctx->new_base_graph->filename);
1617
1618 sort_and_scan_merged_commits(ctx);
1619 }
1620
1621 int write_commit_graph(const char *obj_dir,
1622 struct string_list *pack_indexes,
1623 struct string_list *commit_hex,
1624 unsigned int flags)
1625 {
1626 struct write_commit_graph_context *ctx;
1627 uint32_t i, count_distinct = 0;
1628 int res = 0;
1629
1630 if (!commit_graph_compatible(the_repository))
1631 return 0;
1632
1633 ctx = xcalloc(1, sizeof(struct write_commit_graph_context));
1634 ctx->r = the_repository;
1635 ctx->obj_dir = obj_dir;
1636 ctx->append = flags & COMMIT_GRAPH_APPEND ? 1 : 0;
1637 ctx->report_progress = flags & COMMIT_GRAPH_PROGRESS ? 1 : 0;
1638 ctx->split = flags & COMMIT_GRAPH_SPLIT ? 1 : 0;
1639
1640 if (ctx->split) {
1641 struct commit_graph *g;
1642 prepare_commit_graph(ctx->r);
1643
1644 g = ctx->r->objects->commit_graph;
1645
1646 while (g) {
1647 ctx->num_commit_graphs_before++;
1648 g = g->base_graph;
1649 }
1650
1651 if (ctx->num_commit_graphs_before) {
1652 ALLOC_ARRAY(ctx->commit_graph_filenames_before, ctx->num_commit_graphs_before);
1653 i = ctx->num_commit_graphs_before;
1654 g = ctx->r->objects->commit_graph;
1655
1656 while (g) {
1657 ctx->commit_graph_filenames_before[--i] = xstrdup(g->filename);
1658 g = g->base_graph;
1659 }
1660 }
1661 }
1662
1663 ctx->approx_nr_objects = approximate_object_count();
1664 ctx->oids.alloc = ctx->approx_nr_objects / 32;
1665
1666 if (ctx->split && ctx->oids.alloc > split_strategy_max_commits)
1667 ctx->oids.alloc = split_strategy_max_commits;
1668
1669 if (ctx->append) {
1670 prepare_commit_graph_one(ctx->r, ctx->obj_dir);
1671 if (ctx->r->objects->commit_graph)
1672 ctx->oids.alloc += ctx->r->objects->commit_graph->num_commits;
1673 }
1674
1675 if (ctx->oids.alloc < 1024)
1676 ctx->oids.alloc = 1024;
1677 ALLOC_ARRAY(ctx->oids.list, ctx->oids.alloc);
1678
1679 if (ctx->append && ctx->r->objects->commit_graph) {
1680 struct commit_graph *g = ctx->r->objects->commit_graph;
1681 for (i = 0; i < g->num_commits; i++) {
1682 const unsigned char *hash = g->chunk_oid_lookup + g->hash_len * i;
1683 hashcpy(ctx->oids.list[ctx->oids.nr++].hash, hash);
1684 }
1685 }
1686
1687 if (pack_indexes) {
1688 if ((res = fill_oids_from_packs(ctx, pack_indexes)))
1689 goto cleanup;
1690 }
1691
1692 if (commit_hex)
1693 fill_oids_from_commit_hex(ctx, commit_hex);
1694
1695 if (!pack_indexes && !commit_hex)
1696 fill_oids_from_all_packs(ctx);
1697
1698 close_reachable(ctx);
1699
1700 count_distinct = count_distinct_commits(ctx);
1701
1702 if (count_distinct >= GRAPH_EDGE_LAST_MASK) {
1703 error(_("the commit graph format cannot write %d commits"), count_distinct);
1704 res = -1;
1705 goto cleanup;
1706 }
1707
1708 ctx->commits.alloc = count_distinct;
1709 ALLOC_ARRAY(ctx->commits.list, ctx->commits.alloc);
1710
1711 copy_oids_to_commits(ctx);
1712
1713 if (ctx->commits.nr >= GRAPH_EDGE_LAST_MASK) {
1714 error(_("too many commits to write graph"));
1715 res = -1;
1716 goto cleanup;
1717 }
1718
1719 if (!ctx->commits.nr)
1720 goto cleanup;
1721
1722 if (ctx->split) {
1723 split_graph_merge_strategy(ctx);
1724
1725 merge_commit_graphs(ctx);
1726 } else
1727 ctx->num_commit_graphs_after = 1;
1728
1729 compute_generation_numbers(ctx);
1730
1731 res = write_commit_graph_file(ctx);
1732
1733 cleanup:
1734 free(ctx->graph_name);
1735 free(ctx->commits.list);
1736 free(ctx->oids.list);
1737
1738 if (ctx->commit_graph_filenames_after) {
1739 for (i = 0; i < ctx->num_commit_graphs_after; i++) {
1740 free(ctx->commit_graph_filenames_after[i]);
1741 free(ctx->commit_graph_hash_after[i]);
1742 }
1743
1744 for (i = 0; i < ctx->num_commit_graphs_before; i++)
1745 free(ctx->commit_graph_filenames_before[i]);
1746
1747 free(ctx->commit_graph_filenames_after);
1748 free(ctx->commit_graph_filenames_before);
1749 free(ctx->commit_graph_hash_after);
1750 }
1751
1752 free(ctx);
1753
1754 return res;
1755 }
1756
1757 #define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
1758 static int verify_commit_graph_error;
1759
1760 static void graph_report(const char *fmt, ...)
1761 {
1762 va_list ap;
1763
1764 verify_commit_graph_error = 1;
1765 va_start(ap, fmt);
1766 vfprintf(stderr, fmt, ap);
1767 fprintf(stderr, "\n");
1768 va_end(ap);
1769 }
1770
1771 #define GENERATION_ZERO_EXISTS 1
1772 #define GENERATION_NUMBER_EXISTS 2
1773
1774 int verify_commit_graph(struct repository *r, struct commit_graph *g)
1775 {
1776 uint32_t i, cur_fanout_pos = 0;
1777 struct object_id prev_oid, cur_oid, checksum;
1778 int generation_zero = 0;
1779 struct hashfile *f;
1780 int devnull;
1781 struct progress *progress = NULL;
1782
1783 if (!g) {
1784 graph_report("no commit-graph file loaded");
1785 return 1;
1786 }
1787
1788 verify_commit_graph_error = verify_commit_graph_lite(g);
1789 if (verify_commit_graph_error)
1790 return verify_commit_graph_error;
1791
1792 devnull = open("/dev/null", O_WRONLY);
1793 f = hashfd(devnull, NULL);
1794 hashwrite(f, g->data, g->data_len - g->hash_len);
1795 finalize_hashfile(f, checksum.hash, CSUM_CLOSE);
1796 if (!hasheq(checksum.hash, g->data + g->data_len - g->hash_len)) {
1797 graph_report(_("the commit-graph file has incorrect checksum and is likely corrupt"));
1798 verify_commit_graph_error = VERIFY_COMMIT_GRAPH_ERROR_HASH;
1799 }
1800
1801 for (i = 0; i < g->num_commits; i++) {
1802 struct commit *graph_commit;
1803
1804 hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
1805
1806 if (i && oidcmp(&prev_oid, &cur_oid) >= 0)
1807 graph_report(_("commit-graph has incorrect OID order: %s then %s"),
1808 oid_to_hex(&prev_oid),
1809 oid_to_hex(&cur_oid));
1810
1811 oidcpy(&prev_oid, &cur_oid);
1812
1813 while (cur_oid.hash[0] > cur_fanout_pos) {
1814 uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
1815
1816 if (i != fanout_value)
1817 graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
1818 cur_fanout_pos, fanout_value, i);
1819 cur_fanout_pos++;
1820 }
1821
1822 graph_commit = lookup_commit(r, &cur_oid);
1823 if (!parse_commit_in_graph_one(r, g, graph_commit))
1824 graph_report(_("failed to parse commit %s from commit-graph"),
1825 oid_to_hex(&cur_oid));
1826 }
1827
1828 while (cur_fanout_pos < 256) {
1829 uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
1830
1831 if (g->num_commits != fanout_value)
1832 graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
1833 cur_fanout_pos, fanout_value, i);
1834
1835 cur_fanout_pos++;
1836 }
1837
1838 if (verify_commit_graph_error & ~VERIFY_COMMIT_GRAPH_ERROR_HASH)
1839 return verify_commit_graph_error;
1840
1841 progress = start_progress(_("Verifying commits in commit graph"),
1842 g->num_commits);
1843 for (i = 0; i < g->num_commits; i++) {
1844 struct commit *graph_commit, *odb_commit;
1845 struct commit_list *graph_parents, *odb_parents;
1846 uint32_t max_generation = 0;
1847
1848 display_progress(progress, i + 1);
1849 hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
1850
1851 graph_commit = lookup_commit(r, &cur_oid);
1852 odb_commit = (struct commit *)create_object(r, cur_oid.hash, alloc_commit_node(r));
1853 if (parse_commit_internal(odb_commit, 0, 0)) {
1854 graph_report(_("failed to parse commit %s from object database for commit-graph"),
1855 oid_to_hex(&cur_oid));
1856 continue;
1857 }
1858
1859 if (!oideq(&get_commit_tree_in_graph_one(r, g, graph_commit)->object.oid,
1860 get_commit_tree_oid(odb_commit)))
1861 graph_report(_("root tree OID for commit %s in commit-graph is %s != %s"),
1862 oid_to_hex(&cur_oid),
1863 oid_to_hex(get_commit_tree_oid(graph_commit)),
1864 oid_to_hex(get_commit_tree_oid(odb_commit)));
1865
1866 graph_parents = graph_commit->parents;
1867 odb_parents = odb_commit->parents;
1868
1869 while (graph_parents) {
1870 if (odb_parents == NULL) {
1871 graph_report(_("commit-graph parent list for commit %s is too long"),
1872 oid_to_hex(&cur_oid));
1873 break;
1874 }
1875
1876 if (!oideq(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
1877 graph_report(_("commit-graph parent for %s is %s != %s"),
1878 oid_to_hex(&cur_oid),
1879 oid_to_hex(&graph_parents->item->object.oid),
1880 oid_to_hex(&odb_parents->item->object.oid));
1881
1882 if (graph_parents->item->generation > max_generation)
1883 max_generation = graph_parents->item->generation;
1884
1885 graph_parents = graph_parents->next;
1886 odb_parents = odb_parents->next;
1887 }
1888
1889 if (odb_parents != NULL)
1890 graph_report(_("commit-graph parent list for commit %s terminates early"),
1891 oid_to_hex(&cur_oid));
1892
1893 if (!graph_commit->generation) {
1894 if (generation_zero == GENERATION_NUMBER_EXISTS)
1895 graph_report(_("commit-graph has generation number zero for commit %s, but non-zero elsewhere"),
1896 oid_to_hex(&cur_oid));
1897 generation_zero = GENERATION_ZERO_EXISTS;
1898 } else if (generation_zero == GENERATION_ZERO_EXISTS)
1899 graph_report(_("commit-graph has non-zero generation number for commit %s, but zero elsewhere"),
1900 oid_to_hex(&cur_oid));
1901
1902 if (generation_zero == GENERATION_ZERO_EXISTS)
1903 continue;
1904
1905 /*
1906 * If one of our parents has generation GENERATION_NUMBER_MAX, then
1907 * our generation is also GENERATION_NUMBER_MAX. Decrement to avoid
1908 * extra logic in the following condition.
1909 */
1910 if (max_generation == GENERATION_NUMBER_MAX)
1911 max_generation--;
1912
1913 if (graph_commit->generation != max_generation + 1)
1914 graph_report(_("commit-graph generation for commit %s is %u != %u"),
1915 oid_to_hex(&cur_oid),
1916 graph_commit->generation,
1917 max_generation + 1);
1918
1919 if (graph_commit->date != odb_commit->date)
1920 graph_report(_("commit date for commit %s in commit-graph is %"PRItime" != %"PRItime),
1921 oid_to_hex(&cur_oid),
1922 graph_commit->date,
1923 odb_commit->date);
1924 }
1925 stop_progress(&progress);
1926
1927 return verify_commit_graph_error;
1928 }
1929
1930 void free_commit_graph(struct commit_graph *g)
1931 {
1932 if (!g)
1933 return;
1934 if (g->graph_fd >= 0) {
1935 munmap((void *)g->data, g->data_len);
1936 g->data = NULL;
1937 close(g->graph_fd);
1938 }
1939 free(g->filename);
1940 free(g);
1941 }