commit-graph: write commit-graph chains
[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"
d6538246
DS
16#include "hashmap.h"
17#include "replace-object.h"
7b0f2292 18#include "progress.h"
08fd81c9
DS
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" */
5af7417b 24#define GRAPH_CHUNKID_EXTRAEDGES 0x45444745 /* "EDGE" */
118bd570 25#define GRAPH_CHUNKID_BASE 0x42415345 /* "BASE" */
08fd81c9 26
c1665998 27#define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16)
08fd81c9
DS
28
29#define GRAPH_VERSION_1 0x1
30#define GRAPH_VERSION GRAPH_VERSION_1
31
5af7417b 32#define GRAPH_EXTRA_EDGES_NEEDED 0x80000000
08fd81c9
DS
33#define GRAPH_EDGE_LAST_MASK 0x7fffffff
34#define GRAPH_PARENT_NONE 0x70000000
35
36#define GRAPH_LAST_EDGE 0x80000000
37
0e3b97cc 38#define GRAPH_HEADER_SIZE 8
08fd81c9
DS
39#define GRAPH_FANOUT_SIZE (4 * 256)
40#define GRAPH_CHUNKLOOKUP_WIDTH 12
0e3b97cc 41#define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
c1665998 42 + GRAPH_FANOUT_SIZE + the_hash_algo->rawsz)
08fd81c9 43
2a2e32bd 44char *get_commit_graph_filename(const char *obj_dir)
08fd81c9
DS
45{
46 return xstrfmt("%s/info/commit-graph", obj_dir);
47}
48
5c84b339
DS
49static 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
57static char *get_chain_filename(const char *obj_dir)
58{
59 return xstrfmt("%s/info/commit-graphs/commit-graph-chain", obj_dir);
60}
61
c1665998 62static uint8_t oid_version(void)
63{
64 return 1;
65}
66
2a2e32bd
DS
67static 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
d6538246
DS
75extern int read_replace_refs;
76
77static int commit_graph_compatible(struct repository *r)
78{
5cef295f
DS
79 if (!r->gitdir)
80 return 0;
81
d6538246
DS
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
20fd6d57
DS
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
d6538246
DS
94 return 1;
95}
96
61df89c8
ÆAB
97int 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
67a530fa 109struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st)
2a2e32bd
DS
110{
111 void *graph_map;
2a2e32bd 112 size_t graph_size;
aa658574 113 struct commit_graph *ret;
2a2e32bd 114
61df89c8 115 graph_size = xsize_t(st->st_size);
2a2e32bd
DS
116
117 if (graph_size < GRAPH_MIN_SIZE) {
118 close(fd);
67a530fa 119 error(_("commit-graph file is too small"));
61df89c8 120 return NULL;
2a2e32bd
DS
121 }
122 graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
aa658574
JS
123 ret = parse_commit_graph(graph_map, fd, graph_size);
124
125 if (!ret) {
126 munmap(graph_map, graph_size);
127 close(fd);
aa658574
JS
128 }
129
130 return ret;
131}
132
2ac138d5
ÆAB
133static 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
aa658574
JS
163struct 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
2a2e32bd
DS
180 data = (const unsigned char *)graph_map;
181
182 graph_signature = get_be32(data);
183 if (graph_signature != GRAPH_SIGNATURE) {
93b4405f 184 error(_("commit-graph signature %X does not match signature %X"),
2a2e32bd 185 graph_signature, GRAPH_SIGNATURE);
aa658574 186 return NULL;
2a2e32bd
DS
187 }
188
189 graph_version = *(unsigned char*)(data + 4);
190 if (graph_version != GRAPH_VERSION) {
93b4405f 191 error(_("commit-graph version %X does not match version %X"),
2a2e32bd 192 graph_version, GRAPH_VERSION);
aa658574 193 return NULL;
2a2e32bd
DS
194 }
195
196 hash_version = *(unsigned char*)(data + 5);
c1665998 197 if (hash_version != oid_version()) {
93b4405f 198 error(_("commit-graph hash version %X does not match version %X"),
c1665998 199 hash_version, oid_version());
aa658574 200 return NULL;
2a2e32bd
DS
201 }
202
203 graph = alloc_commit_graph();
204
c1665998 205 graph->hash_len = the_hash_algo->rawsz;
2a2e32bd
DS
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++) {
d2b86fba
JS
215 uint32_t chunk_id;
216 uint64_t chunk_offset;
2a2e32bd
DS
217 int chunk_repeated = 0;
218
d2b86fba
JS
219 if (data + graph_size - chunk_lookup <
220 GRAPH_CHUNKLOOKUP_WIDTH) {
93b4405f 221 error(_("commit-graph chunk lookup table entry missing; file may be incomplete"));
d2b86fba
JS
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
2a2e32bd
DS
229 chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
230
c1665998 231 if (chunk_offset > graph_size - the_hash_algo->rawsz) {
93b4405f 232 error(_("commit-graph improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32),
2a2e32bd 233 (uint32_t)chunk_offset);
aa658574
JS
234 free(graph);
235 return NULL;
2a2e32bd
DS
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
5af7417b
SG
260 case GRAPH_CHUNKID_EXTRAEDGES:
261 if (graph->chunk_extra_edges)
2a2e32bd
DS
262 chunk_repeated = 1;
263 else
5af7417b 264 graph->chunk_extra_edges = data + chunk_offset;
2a2e32bd 265 break;
118bd570
DS
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;
2a2e32bd
DS
272 }
273
274 if (chunk_repeated) {
93b4405f 275 error(_("commit-graph chunk id %08x appears multiple times"), chunk_id);
aa658574
JS
276 free(graph);
277 return NULL;
2a2e32bd
DS
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
118bd570
DS
290 hashcpy(graph->oid.hash, graph->data + graph->data_len - graph->hash_len);
291
2ac138d5
ÆAB
292 if (verify_commit_graph_lite(graph))
293 return NULL;
294
2a2e32bd 295 return graph;
2a2e32bd
DS
296}
297
61df89c8
ÆAB
298static struct commit_graph *load_commit_graph_one(const char *graph_file)
299{
300
301 struct stat st;
302 int fd;
6c622f9f 303 struct commit_graph *g;
61df89c8
ÆAB
304 int open_ok = open_commit_graph(graph_file, &fd, &st);
305
306 if (!open_ok)
307 return NULL;
308
6c622f9f
DS
309 g = load_commit_graph_one_fd_st(fd, &st);
310
311 if (g)
312 g->filename = xstrdup(graph_file);
313
314 return g;
61df89c8
ÆAB
315}
316
5c84b339
DS
317static 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
326static 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
118bd570
DS
333 if (n && !g->chunk_base_graphs) {
334 warning(_("commit-graph has no base graphs chunk"));
335 return 0;
336 }
337
5c84b339
DS
338 while (n) {
339 n--;
118bd570
DS
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
5c84b339
DS
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
359static 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
412static 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
dade47c0 422static void prepare_commit_graph_one(struct repository *r, const char *obj_dir)
177722b3 423{
177722b3 424
dade47c0 425 if (r->objects->commit_graph)
177722b3
DS
426 return;
427
5c84b339 428 r->objects->commit_graph = read_commit_graph_one(r, obj_dir);
177722b3
DS
429}
430
5faf357b
JT
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 */
dade47c0 437static int prepare_commit_graph(struct repository *r)
177722b3 438{
263db403 439 struct object_directory *odb;
dade47c0
JT
440 int config_value;
441
43d35618
ÆAB
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
dade47c0
JT
446 if (r->objects->commit_graph_attempted)
447 return !!r->objects->commit_graph;
448 r->objects->commit_graph_attempted = 1;
449
859fdc0c
DS
450 if (!git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
451 (repo_config_get_bool(r, "core.commitgraph", &config_value) ||
452 !config_value))
dade47c0
JT
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 */
5faf357b
JT
459 return 0;
460
d6538246
DS
461 if (!commit_graph_compatible(r))
462 return 0;
463
dade47c0 464 prepare_alt_odb(r);
f0eaf638 465 for (odb = r->objects->odb;
263db403
JK
466 !r->objects->commit_graph && odb;
467 odb = odb->next)
468 prepare_commit_graph_one(r, odb->path);
dade47c0 469 return !!r->objects->commit_graph;
177722b3
DS
470}
471
6cc01743
DS
472int 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
d4f4d60f
DS
490static 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
c3a3a964 499void close_commit_graph(struct raw_object_store *o)
177722b3 500{
d4f4d60f 501 close_commit_graph_one(o->commit_graph);
c3a3a964 502 o->commit_graph = NULL;
177722b3
DS
503}
504
505static 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
d4f4d60f
DS
511static 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
4f542b7a
SB
531static struct commit_list **insert_parent_or_die(struct repository *r,
532 struct commit_graph *g,
d4f4d60f 533 uint32_t pos,
177722b3
DS
534 struct commit_list **pptr)
535{
536 struct commit *c;
537 struct object_id oid;
96af91d4 538
d4f4d60f
DS
539 if (pos >= g->num_commits + g->num_commits_in_base)
540 die("invalid parent position %"PRIu32, pos);
53614b13 541
d4f4d60f 542 load_oid_from_graph(g, pos, &oid);
4f542b7a 543 c = lookup_commit(r, &oid);
177722b3 544 if (!c)
4f5b532d 545 die(_("could not find commit %s"), oid_to_hex(&oid));
177722b3
DS
546 c->graph_pos = pos;
547 return &commit_list_insert(c, pptr)->next;
548}
549
e2838d85
DS
550static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
551{
d4f4d60f
DS
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;
e2838d85
DS
560 item->graph_pos = pos;
561 item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
562}
563
4f542b7a
SB
564static int fill_commit_in_graph(struct repository *r,
565 struct commit *item,
566 struct commit_graph *g, uint32_t pos)
177722b3 567{
177722b3
DS
568 uint32_t edge_value;
569 uint32_t *parent_data_ptr;
570 uint64_t date_low, date_high;
571 struct commit_list **pptr;
d4f4d60f
DS
572 const unsigned char *commit_data;
573 uint32_t lex_index;
177722b3 574
d4f4d60f
DS
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 */
177722b3 585 item->graph_pos = pos;
d4f4d60f
DS
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;
177722b3 591
7b8a21db 592 item->maybe_tree = NULL;
177722b3
DS
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
83073cc9
DS
598 item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
599
177722b3
DS
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;
4f542b7a 605 pptr = insert_parent_or_die(r, g, edge_value, pptr);
177722b3
DS
606
607 edge_value = get_be32(commit_data + g->hash_len + 4);
608 if (edge_value == GRAPH_PARENT_NONE)
609 return 1;
5af7417b 610 if (!(edge_value & GRAPH_EXTRA_EDGES_NEEDED)) {
4f542b7a 611 pptr = insert_parent_or_die(r, g, edge_value, pptr);
177722b3
DS
612 return 1;
613 }
614
5af7417b 615 parent_data_ptr = (uint32_t*)(g->chunk_extra_edges +
177722b3
DS
616 4 * (uint64_t)(edge_value & GRAPH_EDGE_LAST_MASK));
617 do {
618 edge_value = get_be32(parent_data_ptr);
4f542b7a 619 pptr = insert_parent_or_die(r, g,
177722b3
DS
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
e2838d85
DS
628static 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 {
d4f4d60f
DS
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;
e2838d85
DS
646 }
647}
648
4f542b7a
SB
649static int parse_commit_in_graph_one(struct repository *r,
650 struct commit_graph *g,
651 struct commit *item)
177722b3 652{
e2838d85
DS
653 uint32_t pos;
654
177722b3
DS
655 if (item->object.parsed)
656 return 1;
ee797053
DS
657
658 if (find_commit_in_graph(item, g, &pos))
4f542b7a 659 return fill_commit_in_graph(r, item, g, pos);
ee797053
DS
660
661 return 0;
662}
663
dade47c0 664int parse_commit_in_graph(struct repository *r, struct commit *item)
ee797053 665{
dade47c0 666 if (!prepare_commit_graph(r))
ee797053 667 return 0;
4f542b7a 668 return parse_commit_in_graph_one(r, r->objects->commit_graph, item);
177722b3
DS
669}
670
dade47c0 671void load_commit_graph_info(struct repository *r, struct commit *item)
e2838d85
DS
672{
673 uint32_t pos;
dade47c0 674 if (!prepare_commit_graph(r))
e2838d85 675 return;
dade47c0
JT
676 if (find_commit_in_graph(item, r->objects->commit_graph, &pos))
677 fill_commit_graph_info(item, r->objects->commit_graph, pos);
e2838d85
DS
678}
679
4f542b7a
SB
680static struct tree *load_tree_for_commit(struct repository *r,
681 struct commit_graph *g,
682 struct commit *c)
7b8a21db
DS
683{
684 struct object_id oid;
d4f4d60f
DS
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);
7b8a21db
DS
692
693 hashcpy(oid.hash, commit_data);
4f542b7a 694 c->maybe_tree = lookup_tree(r, &oid);
7b8a21db
DS
695
696 return c->maybe_tree;
697}
698
4f542b7a
SB
699static struct tree *get_commit_tree_in_graph_one(struct repository *r,
700 struct commit_graph *g,
0cbef8f8 701 const struct commit *c)
7b8a21db
DS
702{
703 if (c->maybe_tree)
704 return c->maybe_tree;
705 if (c->graph_pos == COMMIT_NOT_FROM_GRAPH)
0cbef8f8
DS
706 BUG("get_commit_tree_in_graph_one called from non-commit-graph commit");
707
4f542b7a 708 return load_tree_for_commit(r, g, (struct commit *)c);
0cbef8f8 709}
7b8a21db 710
dade47c0 711struct tree *get_commit_tree_in_graph(struct repository *r, const struct commit *c)
0cbef8f8 712{
4f542b7a 713 return get_commit_tree_in_graph_one(r, r->objects->commit_graph, c);
7b8a21db
DS
714}
715
c9905bea
DS
716struct packed_commit_list {
717 struct commit **list;
718 int nr;
719 int alloc;
720};
721
722struct packed_oid_list {
723 struct object_id *list;
724 int nr;
725 int alloc;
726};
727
728struct 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;
6c622f9f
DS
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
c9905bea 749 unsigned append:1,
6c622f9f
DS
750 report_progress:1,
751 split:1;
c9905bea
DS
752};
753
08fd81c9 754static void write_graph_chunk_fanout(struct hashfile *f,
c9905bea 755 struct write_commit_graph_context *ctx)
08fd81c9
DS
756{
757 int i, count = 0;
c9905bea 758 struct commit **list = ctx->commits.list;
08fd81c9
DS
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++) {
c9905bea 766 while (count < ctx->commits.nr) {
08fd81c9
DS
767 if ((*list)->object.oid.hash[0] != i)
768 break;
c9905bea 769 display_progress(ctx->progress, ++ctx->progress_cnt);
08fd81c9
DS
770 count++;
771 list++;
772 }
773
774 hashwrite_be32(f, count);
775 }
776}
777
778static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
c9905bea 779 struct write_commit_graph_context *ctx)
08fd81c9 780{
c9905bea 781 struct commit **list = ctx->commits.list;
08fd81c9 782 int count;
c9905bea
DS
783 for (count = 0; count < ctx->commits.nr; count++, list++) {
784 display_progress(ctx->progress, ++ctx->progress_cnt);
08fd81c9 785 hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
53035c4f 786 }
08fd81c9
DS
787}
788
789static 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
795static void write_graph_chunk_data(struct hashfile *f, int hash_len,
c9905bea 796 struct write_commit_graph_context *ctx)
08fd81c9 797{
c9905bea
DS
798 struct commit **list = ctx->commits.list;
799 struct commit **last = ctx->commits.list + ctx->commits.nr;
08fd81c9
DS
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];
c9905bea 806 display_progress(ctx->progress, ++ctx->progress_cnt);
08fd81c9 807
43d35618 808 parse_commit_no_graph(*list);
2e27bd77 809 hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
08fd81c9
DS
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,
c9905bea
DS
817 ctx->commits.list,
818 ctx->commits.nr,
08fd81c9
DS
819 commit_to_sha1);
820
6c622f9f
DS
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
08fd81c9 831 if (edge_value < 0)
cce99cd8
DS
832 BUG("missing parent %s for commit %s",
833 oid_to_hex(&parent->item->object.oid),
834 oid_to_hex(&(*list)->object.oid));
08fd81c9
DS
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)
5af7417b 845 edge_value = GRAPH_EXTRA_EDGES_NEEDED | num_extra_edges;
08fd81c9
DS
846 else {
847 edge_value = sha1_pos(parent->item->object.oid.hash,
c9905bea
DS
848 ctx->commits.list,
849 ctx->commits.nr,
08fd81c9 850 commit_to_sha1);
6c622f9f
DS
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
08fd81c9 862 if (edge_value < 0)
cce99cd8
DS
863 BUG("missing parent %s for commit %s",
864 oid_to_hex(&parent->item->object.oid),
865 oid_to_hex(&(*list)->object.oid));
08fd81c9
DS
866 }
867
868 hashwrite_be32(f, edge_value);
869
5af7417b 870 if (edge_value & GRAPH_EXTRA_EDGES_NEEDED) {
08fd81c9
DS
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
3258c663
DS
882 packedDate[0] |= htonl((*list)->generation << 2);
883
08fd81c9
DS
884 packedDate[1] = htonl((*list)->date);
885 hashwrite(f, packedDate, 8);
886
887 list++;
888 }
889}
890
5af7417b 891static void write_graph_chunk_extra_edges(struct hashfile *f,
c9905bea 892 struct write_commit_graph_context *ctx)
08fd81c9 893{
c9905bea
DS
894 struct commit **list = ctx->commits.list;
895 struct commit **last = ctx->commits.list + ctx->commits.nr;
08fd81c9
DS
896 struct commit_list *parent;
897
898 while (list < last) {
899 int num_parents = 0;
53035c4f 900
c9905bea 901 display_progress(ctx->progress, ++ctx->progress_cnt);
53035c4f 902
08fd81c9
DS
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,
c9905bea
DS
915 ctx->commits.list,
916 ctx->commits.nr,
08fd81c9
DS
917 commit_to_sha1);
918
6c622f9f
DS
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
08fd81c9 929 if (edge_value < 0)
cce99cd8
DS
930 BUG("missing parent %s for commit %s",
931 oid_to_hex(&parent->item->object.oid),
932 oid_to_hex(&(*list)->object.oid));
08fd81c9
DS
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
3cbc6ed3 943static int oid_compare(const void *_a, const void *_b)
08fd81c9
DS
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
08fd81c9
DS
950static int add_packed_commits(const struct object_id *oid,
951 struct packed_git *pack,
952 uint32_t pos,
953 void *data)
954{
c9905bea 955 struct write_commit_graph_context *ctx = (struct write_commit_graph_context*)data;
08fd81c9
DS
956 enum object_type type;
957 off_t offset = nth_packed_object_offset(pack, pos);
958 struct object_info oi = OBJECT_INFO_INIT;
959
c9905bea
DS
960 if (ctx->progress)
961 display_progress(ctx->progress, ++ctx->progress_done);
7b0f2292 962
08fd81c9 963 oi.typep = &type;
c9905bea 964 if (packed_object_info(ctx->r, pack, offset, &oi) < 0)
4f5b532d 965 die(_("unable to get type of object %s"), oid_to_hex(oid));
08fd81c9
DS
966
967 if (type != OBJ_COMMIT)
968 return 0;
969
c9905bea
DS
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++;
08fd81c9
DS
973
974 return 0;
975}
976
c9905bea 977static void add_missing_parents(struct write_commit_graph_context *ctx, struct commit *commit)
4f2542b4
DS
978{
979 struct commit_list *parent;
980 for (parent = commit->parents; parent; parent = parent->next) {
981 if (!(parent->item->object.flags & UNINTERESTING)) {
c9905bea
DS
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++;
4f2542b4
DS
985 parent->item->object.flags |= UNINTERESTING;
986 }
987 }
988}
989
c9905bea 990static void close_reachable(struct write_commit_graph_context *ctx)
4f2542b4 991{
49bbc57a 992 int i;
4f2542b4
DS
993 struct commit *commit;
994
c9905bea
DS
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]);
4f2542b4
DS
1002 if (commit)
1003 commit->object.flags |= UNINTERESTING;
1004 }
c9905bea 1005 stop_progress(&ctx->progress);
4f2542b4
DS
1006
1007 /*
c9905bea 1008 * As this loop runs, ctx->oids.nr may grow, but not more
4f2542b4
DS
1009 * than the number of missing commits in the reachable
1010 * closure.
1011 */
c9905bea
DS
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]);
4f2542b4 1019
6c622f9f
DS
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))
c9905bea 1027 add_missing_parents(ctx, commit);
4f2542b4 1028 }
c9905bea 1029 stop_progress(&ctx->progress);
4f2542b4 1030
c9905bea
DS
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]);
4f2542b4
DS
1038
1039 if (commit)
1040 commit->object.flags &= ~UNINTERESTING;
1041 }
c9905bea 1042 stop_progress(&ctx->progress);
4f2542b4
DS
1043}
1044
c9905bea 1045static void compute_generation_numbers(struct write_commit_graph_context *ctx)
3258c663
DS
1046{
1047 int i;
1048 struct commit_list *list = NULL;
1049
c9905bea
DS
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)
3258c663
DS
1058 continue;
1059
c9905bea 1060 commit_list_insert(ctx->commits.list[i], &list);
3258c663
DS
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 }
c9905bea 1087 stop_progress(&ctx->progress);
3258c663
DS
1088}
1089
59fb8770
DS
1090static 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
5af80394 1100int write_commit_graph_reachable(const char *obj_dir, unsigned int flags)
59fb8770 1101{
f4dbdfc4 1102 struct string_list list = STRING_LIST_INIT_DUP;
e103f727 1103 int result;
59fb8770 1104
59fb8770 1105 for_each_ref(add_ref_to_list, &list);
e103f727 1106 result = write_commit_graph(obj_dir, NULL, &list,
5af80394 1107 flags);
f4dbdfc4
DS
1108
1109 string_list_clear(&list, 0);
e103f727 1110 return result;
59fb8770
DS
1111}
1112
ef5b83f2
DS
1113static 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
4c9efe85
DS
1158static 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
b2c83060
DS
1196static 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
014e3440
DS
1209static 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 */
3cbc6ed3 1218 QSORT(ctx->oids.list, ctx->oids.nr, oid_compare);
014e3440
DS
1219
1220 for (i = 1; i < ctx->oids.nr; i++) {
1221 display_progress(ctx->progress, i + 1);
6c622f9f
DS
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
014e3440 1230 count_distinct++;
6c622f9f 1231 }
014e3440
DS
1232 }
1233 stop_progress(&ctx->progress);
1234
1235 return count_distinct;
1236}
1237
f998d542
DS
1238static 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
6c622f9f 1254 ALLOC_GROW(ctx->commits.list, ctx->commits.nr + 1, ctx->commits.alloc);
f998d542 1255 ctx->commits.list[ctx->commits.nr] = lookup_commit(ctx->r, &ctx->oids.list[i]);
6c622f9f
DS
1256
1257 if (ctx->split &&
1258 ctx->commits.list[ctx->commits.nr]->graph_pos != COMMIT_NOT_FROM_GRAPH)
1259 continue;
1260
f998d542
DS
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
6c622f9f
DS
1275static 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
1288static 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
1301static void init_commit_graph_chain(struct write_commit_graph_context *ctx)
1302{
1303 struct commit_graph *g = ctx->r->objects->commit_graph;
1304 uint32_t i;
1305
1306 ctx->new_base_graph = g;
1307 ctx->base_graph_name = xstrdup(g->filename);
1308 ctx->new_num_commits_in_base = g->num_commits + g->num_commits_in_base;
1309
1310 ctx->num_commit_graphs_after = ctx->num_commit_graphs_before + 1;
1311
1312 ALLOC_ARRAY(ctx->commit_graph_filenames_after, ctx->num_commit_graphs_after);
1313 ALLOC_ARRAY(ctx->commit_graph_hash_after, ctx->num_commit_graphs_after);
1314
1315 for (i = 0; i < ctx->num_commit_graphs_before - 1; i++)
1316 ctx->commit_graph_filenames_after[i] = xstrdup(ctx->commit_graph_filenames_before[i]);
1317
1318 if (ctx->num_commit_graphs_before)
1319 ctx->commit_graph_filenames_after[ctx->num_commit_graphs_before - 1] =
1320 get_split_graph_filename(ctx->obj_dir, oid_to_hex(&g->oid));
1321
1322 i = ctx->num_commit_graphs_before - 1;
1323
1324 while (g) {
1325 ctx->commit_graph_hash_after[i] = xstrdup(oid_to_hex(&g->oid));
1326 i--;
1327 g = g->base_graph;
1328 }
1329}
1330
238def57 1331static int write_commit_graph_file(struct write_commit_graph_context *ctx)
08fd81c9 1332{
238def57 1333 uint32_t i;
6c622f9f 1334 int fd;
08fd81c9 1335 struct hashfile *f;
08fd81c9 1336 struct lock_file lk = LOCK_INIT;
6c622f9f
DS
1337 uint32_t chunk_ids[6];
1338 uint64_t chunk_offsets[6];
c1665998 1339 const unsigned hashsz = the_hash_algo->rawsz;
28944739 1340 struct strbuf progress_title = STRBUF_INIT;
144354b0 1341 int num_chunks = 3;
6c622f9f
DS
1342 struct object_id file_hash;
1343
1344 if (ctx->split) {
1345 struct strbuf tmp_file = STRBUF_INIT;
1346
1347 strbuf_addf(&tmp_file,
1348 "%s/info/commit-graphs/tmp_graph_XXXXXX",
1349 ctx->obj_dir);
1350 ctx->graph_name = strbuf_detach(&tmp_file, NULL);
1351 } else {
1352 ctx->graph_name = get_commit_graph_filename(ctx->obj_dir);
1353 }
238def57 1354
238def57
DS
1355 if (safe_create_leading_directories(ctx->graph_name)) {
1356 UNLEAK(ctx->graph_name);
1357 error(_("unable to create leading directories of %s"),
1358 ctx->graph_name);
1359 return -1;
1360 }
1361
6c622f9f
DS
1362 if (ctx->split) {
1363 char *lock_name = get_chain_filename(ctx->obj_dir);
1364
1365 hold_lock_file_for_update(&lk, lock_name, LOCK_DIE_ON_ERROR);
1366
1367 fd = git_mkstemp_mode(ctx->graph_name, 0444);
1368 if (fd < 0) {
1369 error(_("unable to create '%s'"), ctx->graph_name);
1370 return -1;
1371 }
1372
1373 f = hashfd(fd, ctx->graph_name);
1374 } else {
1375 hold_lock_file_for_update(&lk, ctx->graph_name, LOCK_DIE_ON_ERROR);
1376 fd = lk.tempfile->fd;
1377 f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
1378 }
238def57 1379
238def57
DS
1380 chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
1381 chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
1382 chunk_ids[2] = GRAPH_CHUNKID_DATA;
144354b0
DS
1383 if (ctx->num_extra_edges) {
1384 chunk_ids[num_chunks] = GRAPH_CHUNKID_EXTRAEDGES;
1385 num_chunks++;
1386 }
6c622f9f
DS
1387 if (ctx->num_commit_graphs_after > 1) {
1388 chunk_ids[num_chunks] = GRAPH_CHUNKID_BASE;
1389 num_chunks++;
1390 }
144354b0
DS
1391
1392 chunk_ids[num_chunks] = 0;
238def57
DS
1393
1394 chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
1395 chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
1396 chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
1397 chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;
144354b0
DS
1398
1399 num_chunks = 3;
1400 if (ctx->num_extra_edges) {
1401 chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
1402 4 * ctx->num_extra_edges;
1403 num_chunks++;
1404 }
6c622f9f
DS
1405 if (ctx->num_commit_graphs_after > 1) {
1406 chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
1407 hashsz * (ctx->num_commit_graphs_after - 1);
1408 num_chunks++;
1409 }
144354b0
DS
1410
1411 hashwrite_be32(f, GRAPH_SIGNATURE);
1412
1413 hashwrite_u8(f, GRAPH_VERSION);
1414 hashwrite_u8(f, oid_version());
1415 hashwrite_u8(f, num_chunks);
6c622f9f 1416 hashwrite_u8(f, ctx->num_commit_graphs_after - 1);
238def57
DS
1417
1418 for (i = 0; i <= num_chunks; i++) {
1419 uint32_t chunk_write[3];
1420
1421 chunk_write[0] = htonl(chunk_ids[i]);
1422 chunk_write[1] = htonl(chunk_offsets[i] >> 32);
1423 chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
1424 hashwrite(f, chunk_write, 12);
1425 }
1426
1427 if (ctx->report_progress) {
1428 strbuf_addf(&progress_title,
1429 Q_("Writing out commit graph in %d pass",
1430 "Writing out commit graph in %d passes",
1431 num_chunks),
1432 num_chunks);
1433 ctx->progress = start_delayed_progress(
1434 progress_title.buf,
1435 num_chunks * ctx->commits.nr);
1436 }
1437 write_graph_chunk_fanout(f, ctx);
1438 write_graph_chunk_oids(f, hashsz, ctx);
1439 write_graph_chunk_data(f, hashsz, ctx);
1440 if (ctx->num_extra_edges)
1441 write_graph_chunk_extra_edges(f, ctx);
6c622f9f
DS
1442 if (ctx->num_commit_graphs_after > 1 &&
1443 write_graph_chunk_base(f, ctx)) {
1444 return -1;
1445 }
238def57
DS
1446 stop_progress(&ctx->progress);
1447 strbuf_release(&progress_title);
1448
6c622f9f
DS
1449 if (ctx->split && ctx->base_graph_name && ctx->num_commit_graphs_after > 1) {
1450 char *new_base_hash = xstrdup(oid_to_hex(&ctx->new_base_graph->oid));
1451 char *new_base_name = get_split_graph_filename(ctx->obj_dir, new_base_hash);
1452
1453 free(ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2]);
1454 free(ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2]);
1455 ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2] = new_base_name;
1456 ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2] = new_base_hash;
1457 }
1458
c3a3a964 1459 close_commit_graph(ctx->r->objects);
6c622f9f
DS
1460 finalize_hashfile(f, file_hash.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
1461
1462 if (ctx->split) {
1463 FILE *chainf = fdopen_lock_file(&lk, "w");
1464 char *final_graph_name;
1465 int result;
1466
1467 close(fd);
1468
1469 if (!chainf) {
1470 error(_("unable to open commit-graph chain file"));
1471 return -1;
1472 }
1473
1474 if (ctx->base_graph_name) {
1475 result = rename(ctx->base_graph_name,
1476 ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2]);
1477
1478 if (result) {
1479 error(_("failed to rename base commit-graph file"));
1480 return -1;
1481 }
1482 } else {
1483 char *graph_name = get_commit_graph_filename(ctx->obj_dir);
1484 unlink(graph_name);
1485 }
1486
1487 ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1] = xstrdup(oid_to_hex(&file_hash));
1488 final_graph_name = get_split_graph_filename(ctx->obj_dir,
1489 ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1]);
1490 ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 1] = final_graph_name;
1491
1492 result = rename(ctx->graph_name, final_graph_name);
1493
1494 for (i = 0; i < ctx->num_commit_graphs_after; i++)
1495 fprintf(lk.tempfile->fp, "%s\n", ctx->commit_graph_hash_after[i]);
1496
1497 if (result) {
1498 error(_("failed to rename temporary commit-graph file"));
1499 return -1;
1500 }
1501 }
1502
238def57
DS
1503 commit_lock_file(&lk);
1504
1505 return 0;
1506}
1507
1508int write_commit_graph(const char *obj_dir,
1509 struct string_list *pack_indexes,
1510 struct string_list *commit_hex,
1511 unsigned int flags)
1512{
1513 struct write_commit_graph_context *ctx;
1514 uint32_t i, count_distinct = 0;
e103f727 1515 int res = 0;
08fd81c9 1516
d6538246 1517 if (!commit_graph_compatible(the_repository))
e103f727 1518 return 0;
d6538246 1519
c9905bea
DS
1520 ctx = xcalloc(1, sizeof(struct write_commit_graph_context));
1521 ctx->r = the_repository;
1522 ctx->obj_dir = obj_dir;
1523 ctx->append = flags & COMMIT_GRAPH_APPEND ? 1 : 0;
1524 ctx->report_progress = flags & COMMIT_GRAPH_PROGRESS ? 1 : 0;
6c622f9f
DS
1525 ctx->split = flags & COMMIT_GRAPH_SPLIT ? 1 : 0;
1526
1527 if (ctx->split) {
1528 struct commit_graph *g;
1529 prepare_commit_graph(ctx->r);
1530
1531 g = ctx->r->objects->commit_graph;
1532
1533 while (g) {
1534 ctx->num_commit_graphs_before++;
1535 g = g->base_graph;
1536 }
1537
1538 if (ctx->num_commit_graphs_before) {
1539 ALLOC_ARRAY(ctx->commit_graph_filenames_before, ctx->num_commit_graphs_before);
1540 i = ctx->num_commit_graphs_before;
1541 g = ctx->r->objects->commit_graph;
1542
1543 while (g) {
1544 ctx->commit_graph_filenames_before[--i] = xstrdup(g->filename);
1545 g = g->base_graph;
1546 }
1547 }
1548 }
c9905bea
DS
1549
1550 ctx->approx_nr_objects = approximate_object_count();
1551 ctx->oids.alloc = ctx->approx_nr_objects / 32;
1552
1553 if (ctx->append) {
1554 prepare_commit_graph_one(ctx->r, ctx->obj_dir);
1555 if (ctx->r->objects->commit_graph)
1556 ctx->oids.alloc += ctx->r->objects->commit_graph->num_commits;
7547b95b
DS
1557 }
1558
c9905bea
DS
1559 if (ctx->oids.alloc < 1024)
1560 ctx->oids.alloc = 1024;
1561 ALLOC_ARRAY(ctx->oids.list, ctx->oids.alloc);
1562
1563 if (ctx->append && ctx->r->objects->commit_graph) {
1564 struct commit_graph *g = ctx->r->objects->commit_graph;
1565 for (i = 0; i < g->num_commits; i++) {
1566 const unsigned char *hash = g->chunk_oid_lookup + g->hash_len * i;
1567 hashcpy(ctx->oids.list[ctx->oids.nr++].hash, hash);
7547b95b
DS
1568 }
1569 }
1570
049d51a2 1571 if (pack_indexes) {
ef5b83f2
DS
1572 if ((res = fill_oids_from_packs(ctx, pack_indexes)))
1573 goto cleanup;
3d5df01b
DS
1574 }
1575
4c9efe85
DS
1576 if (commit_hex)
1577 fill_oids_from_commit_hex(ctx, commit_hex);
3d5df01b 1578
b2c83060
DS
1579 if (!pack_indexes && !commit_hex)
1580 fill_oids_from_all_packs(ctx);
049d51a2 1581
c9905bea 1582 close_reachable(ctx);
08fd81c9 1583
014e3440 1584 count_distinct = count_distinct_commits(ctx);
08fd81c9 1585
e103f727
DS
1586 if (count_distinct >= GRAPH_EDGE_LAST_MASK) {
1587 error(_("the commit graph format cannot write %d commits"), count_distinct);
1588 res = -1;
1589 goto cleanup;
1590 }
08fd81c9 1591
c9905bea
DS
1592 ctx->commits.alloc = count_distinct;
1593 ALLOC_ARRAY(ctx->commits.list, ctx->commits.alloc);
08fd81c9 1594
f998d542 1595 copy_oids_to_commits(ctx);
08fd81c9 1596
c9905bea 1597 if (ctx->commits.nr >= GRAPH_EDGE_LAST_MASK) {
e103f727
DS
1598 error(_("too many commits to write graph"));
1599 res = -1;
1600 goto cleanup;
1601 }
08fd81c9 1602
6c622f9f
DS
1603 if (!ctx->commits.nr)
1604 goto cleanup;
1605
1606 if (ctx->split)
1607 init_commit_graph_chain(ctx);
1608 else
1609 ctx->num_commit_graphs_after = 1;
1610
c9905bea 1611 compute_generation_numbers(ctx);
08fd81c9 1612
238def57 1613 res = write_commit_graph_file(ctx);
08fd81c9 1614
e103f727 1615cleanup:
238def57 1616 free(ctx->graph_name);
c9905bea
DS
1617 free(ctx->commits.list);
1618 free(ctx->oids.list);
6c622f9f
DS
1619
1620 if (ctx->commit_graph_filenames_after) {
1621 for (i = 0; i < ctx->num_commit_graphs_after; i++) {
1622 free(ctx->commit_graph_filenames_after[i]);
1623 free(ctx->commit_graph_hash_after[i]);
1624 }
1625
1626 for (i = 0; i < ctx->num_commit_graphs_before; i++)
1627 free(ctx->commit_graph_filenames_before[i]);
1628
1629 free(ctx->commit_graph_filenames_after);
1630 free(ctx->commit_graph_filenames_before);
1631 free(ctx->commit_graph_hash_after);
1632 }
1633
c9905bea 1634 free(ctx);
e103f727
DS
1635
1636 return res;
08fd81c9 1637}
283e68c7 1638
41df0e30 1639#define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
283e68c7
DS
1640static int verify_commit_graph_error;
1641
1642static void graph_report(const char *fmt, ...)
1643{
1644 va_list ap;
1645
1646 verify_commit_graph_error = 1;
1647 va_start(ap, fmt);
1648 vfprintf(stderr, fmt, ap);
1649 fprintf(stderr, "\n");
1650 va_end(ap);
1651}
1652
1373e547
DS
1653#define GENERATION_ZERO_EXISTS 1
1654#define GENERATION_NUMBER_EXISTS 2
1655
283e68c7
DS
1656int verify_commit_graph(struct repository *r, struct commit_graph *g)
1657{
9bda8467 1658 uint32_t i, cur_fanout_pos = 0;
41df0e30 1659 struct object_id prev_oid, cur_oid, checksum;
1373e547 1660 int generation_zero = 0;
41df0e30
DS
1661 struct hashfile *f;
1662 int devnull;
1f7f557f 1663 struct progress *progress = NULL;
9bda8467 1664
283e68c7
DS
1665 if (!g) {
1666 graph_report("no commit-graph file loaded");
1667 return 1;
1668 }
1669
2ac138d5 1670 verify_commit_graph_error = verify_commit_graph_lite(g);
9bda8467
DS
1671 if (verify_commit_graph_error)
1672 return verify_commit_graph_error;
1673
41df0e30
DS
1674 devnull = open("/dev/null", O_WRONLY);
1675 f = hashfd(devnull, NULL);
1676 hashwrite(f, g->data, g->data_len - g->hash_len);
1677 finalize_hashfile(f, checksum.hash, CSUM_CLOSE);
67947c34 1678 if (!hasheq(checksum.hash, g->data + g->data_len - g->hash_len)) {
41df0e30
DS
1679 graph_report(_("the commit-graph file has incorrect checksum and is likely corrupt"));
1680 verify_commit_graph_error = VERIFY_COMMIT_GRAPH_ERROR_HASH;
1681 }
1682
9bda8467 1683 for (i = 0; i < g->num_commits; i++) {
2e3c0737
DS
1684 struct commit *graph_commit;
1685
9bda8467
DS
1686 hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
1687
1688 if (i && oidcmp(&prev_oid, &cur_oid) >= 0)
93b4405f 1689 graph_report(_("commit-graph has incorrect OID order: %s then %s"),
9bda8467
DS
1690 oid_to_hex(&prev_oid),
1691 oid_to_hex(&cur_oid));
1692
1693 oidcpy(&prev_oid, &cur_oid);
1694
1695 while (cur_oid.hash[0] > cur_fanout_pos) {
1696 uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
1697
1698 if (i != fanout_value)
93b4405f 1699 graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
9bda8467
DS
1700 cur_fanout_pos, fanout_value, i);
1701 cur_fanout_pos++;
1702 }
2e3c0737 1703
82952964 1704 graph_commit = lookup_commit(r, &cur_oid);
4f542b7a 1705 if (!parse_commit_in_graph_one(r, g, graph_commit))
93b4405f 1706 graph_report(_("failed to parse commit %s from commit-graph"),
2e3c0737 1707 oid_to_hex(&cur_oid));
9bda8467
DS
1708 }
1709
1710 while (cur_fanout_pos < 256) {
1711 uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
1712
1713 if (g->num_commits != fanout_value)
93b4405f 1714 graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
9bda8467
DS
1715 cur_fanout_pos, fanout_value, i);
1716
1717 cur_fanout_pos++;
1718 }
1719
41df0e30 1720 if (verify_commit_graph_error & ~VERIFY_COMMIT_GRAPH_ERROR_HASH)
96af91d4
DS
1721 return verify_commit_graph_error;
1722
1f7f557f
ÆAB
1723 progress = start_progress(_("Verifying commits in commit graph"),
1724 g->num_commits);
96af91d4 1725 for (i = 0; i < g->num_commits; i++) {
2e3c0737 1726 struct commit *graph_commit, *odb_commit;
53614b13 1727 struct commit_list *graph_parents, *odb_parents;
1373e547 1728 uint32_t max_generation = 0;
96af91d4 1729
1f7f557f 1730 display_progress(progress, i + 1);
96af91d4
DS
1731 hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
1732
82952964 1733 graph_commit = lookup_commit(r, &cur_oid);
96af91d4
DS
1734 odb_commit = (struct commit *)create_object(r, cur_oid.hash, alloc_commit_node(r));
1735 if (parse_commit_internal(odb_commit, 0, 0)) {
93b4405f 1736 graph_report(_("failed to parse commit %s from object database for commit-graph"),
96af91d4
DS
1737 oid_to_hex(&cur_oid));
1738 continue;
1739 }
2e3c0737 1740
4f542b7a 1741 if (!oideq(&get_commit_tree_in_graph_one(r, g, graph_commit)->object.oid,
2e3c0737 1742 get_commit_tree_oid(odb_commit)))
93b4405f 1743 graph_report(_("root tree OID for commit %s in commit-graph is %s != %s"),
2e3c0737
DS
1744 oid_to_hex(&cur_oid),
1745 oid_to_hex(get_commit_tree_oid(graph_commit)),
1746 oid_to_hex(get_commit_tree_oid(odb_commit)));
53614b13
DS
1747
1748 graph_parents = graph_commit->parents;
1749 odb_parents = odb_commit->parents;
1750
1751 while (graph_parents) {
1752 if (odb_parents == NULL) {
93b4405f 1753 graph_report(_("commit-graph parent list for commit %s is too long"),
53614b13
DS
1754 oid_to_hex(&cur_oid));
1755 break;
1756 }
1757
9001dc2a 1758 if (!oideq(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
93b4405f 1759 graph_report(_("commit-graph parent for %s is %s != %s"),
53614b13
DS
1760 oid_to_hex(&cur_oid),
1761 oid_to_hex(&graph_parents->item->object.oid),
1762 oid_to_hex(&odb_parents->item->object.oid));
1763
1373e547
DS
1764 if (graph_parents->item->generation > max_generation)
1765 max_generation = graph_parents->item->generation;
1766
53614b13
DS
1767 graph_parents = graph_parents->next;
1768 odb_parents = odb_parents->next;
1769 }
1770
1771 if (odb_parents != NULL)
93b4405f 1772 graph_report(_("commit-graph parent list for commit %s terminates early"),
53614b13 1773 oid_to_hex(&cur_oid));
1373e547
DS
1774
1775 if (!graph_commit->generation) {
1776 if (generation_zero == GENERATION_NUMBER_EXISTS)
93b4405f 1777 graph_report(_("commit-graph has generation number zero for commit %s, but non-zero elsewhere"),
1373e547
DS
1778 oid_to_hex(&cur_oid));
1779 generation_zero = GENERATION_ZERO_EXISTS;
1780 } else if (generation_zero == GENERATION_ZERO_EXISTS)
93b4405f 1781 graph_report(_("commit-graph has non-zero generation number for commit %s, but zero elsewhere"),
1373e547
DS
1782 oid_to_hex(&cur_oid));
1783
1784 if (generation_zero == GENERATION_ZERO_EXISTS)
1785 continue;
1786
1787 /*
1788 * If one of our parents has generation GENERATION_NUMBER_MAX, then
1789 * our generation is also GENERATION_NUMBER_MAX. Decrement to avoid
1790 * extra logic in the following condition.
1791 */
1792 if (max_generation == GENERATION_NUMBER_MAX)
1793 max_generation--;
1794
1795 if (graph_commit->generation != max_generation + 1)
93b4405f 1796 graph_report(_("commit-graph generation for commit %s is %u != %u"),
1373e547
DS
1797 oid_to_hex(&cur_oid),
1798 graph_commit->generation,
1799 max_generation + 1);
88968ebf
DS
1800
1801 if (graph_commit->date != odb_commit->date)
93b4405f 1802 graph_report(_("commit date for commit %s in commit-graph is %"PRItime" != %"PRItime),
88968ebf
DS
1803 oid_to_hex(&cur_oid),
1804 graph_commit->date,
1805 odb_commit->date);
96af91d4 1806 }
1f7f557f 1807 stop_progress(&progress);
96af91d4 1808
283e68c7
DS
1809 return verify_commit_graph_error;
1810}
c3756d5b
JT
1811
1812void free_commit_graph(struct commit_graph *g)
1813{
1814 if (!g)
1815 return;
1816 if (g->graph_fd >= 0) {
1817 munmap((void *)g->data, g->data_len);
1818 g->data = NULL;
1819 close(g->graph_fd);
1820 }
6c622f9f 1821 free(g->filename);
c3756d5b
JT
1822 free(g);
1823}