do not check odb_mkstemp return value for errors
[git/git.git] / pack-bitmap-write.c
CommitLineData
7cc8f971
VM
1#include "cache.h"
2#include "commit.h"
3#include "tag.h"
4#include "diff.h"
5#include "revision.h"
6#include "list-objects.h"
7#include "progress.h"
8#include "pack-revindex.h"
9#include "pack.h"
10#include "pack-bitmap.h"
11#include "sha1-lookup.h"
12#include "pack-objects.h"
13
14struct bitmapped_commit {
15 struct commit *commit;
16 struct ewah_bitmap *bitmap;
17 struct ewah_bitmap *write_as;
18 int flags;
19 int xor_offset;
20 uint32_t commit_pos;
21};
22
23struct bitmap_writer {
24 struct ewah_bitmap *commits;
25 struct ewah_bitmap *trees;
26 struct ewah_bitmap *blobs;
27 struct ewah_bitmap *tags;
28
29 khash_sha1 *bitmaps;
30 khash_sha1 *reused;
31 struct packing_data *to_pack;
32
33 struct bitmapped_commit *selected;
34 unsigned int selected_nr, selected_alloc;
35
36 struct progress *progress;
37 int show_progress;
38 unsigned char pack_checksum[20];
39};
40
41static struct bitmap_writer writer;
42
43void bitmap_writer_show_progress(int show)
44{
45 writer.show_progress = show;
46}
47
48/**
49 * Build the initial type index for the packfile
50 */
51void bitmap_writer_build_type_index(struct pack_idx_entry **index,
52 uint32_t index_nr)
53{
54 uint32_t i;
55
56 writer.commits = ewah_new();
57 writer.trees = ewah_new();
58 writer.blobs = ewah_new();
59 writer.tags = ewah_new();
60
61 for (i = 0; i < index_nr; ++i) {
62 struct object_entry *entry = (struct object_entry *)index[i];
63 enum object_type real_type;
64
65 entry->in_pack_pos = i;
66
67 switch (entry->type) {
68 case OBJ_COMMIT:
69 case OBJ_TREE:
70 case OBJ_BLOB:
71 case OBJ_TAG:
72 real_type = entry->type;
73 break;
74
75 default:
76 real_type = sha1_object_info(entry->idx.sha1, NULL);
77 break;
78 }
79
80 switch (real_type) {
81 case OBJ_COMMIT:
82 ewah_set(writer.commits, i);
83 break;
84
85 case OBJ_TREE:
86 ewah_set(writer.trees, i);
87 break;
88
89 case OBJ_BLOB:
90 ewah_set(writer.blobs, i);
91 break;
92
93 case OBJ_TAG:
94 ewah_set(writer.tags, i);
95 break;
96
97 default:
98 die("Missing type information for %s (%d/%d)",
99 sha1_to_hex(entry->idx.sha1), real_type, entry->type);
100 }
101 }
102}
103
104/**
105 * Compute the actual bitmaps
106 */
107static struct object **seen_objects;
108static unsigned int seen_objects_nr, seen_objects_alloc;
109
110static inline void push_bitmapped_commit(struct commit *commit, struct ewah_bitmap *reused)
111{
112 if (writer.selected_nr >= writer.selected_alloc) {
113 writer.selected_alloc = (writer.selected_alloc + 32) * 2;
2756ca43 114 REALLOC_ARRAY(writer.selected, writer.selected_alloc);
7cc8f971
VM
115 }
116
117 writer.selected[writer.selected_nr].commit = commit;
118 writer.selected[writer.selected_nr].bitmap = reused;
119 writer.selected[writer.selected_nr].flags = 0;
120
121 writer.selected_nr++;
122}
123
124static inline void mark_as_seen(struct object *object)
125{
126 ALLOC_GROW(seen_objects, seen_objects_nr + 1, seen_objects_alloc);
127 seen_objects[seen_objects_nr++] = object;
128}
129
130static inline void reset_all_seen(void)
131{
132 unsigned int i;
133 for (i = 0; i < seen_objects_nr; ++i) {
134 seen_objects[i]->flags &= ~(SEEN | ADDED | SHOWN);
135 }
136 seen_objects_nr = 0;
137}
138
139static uint32_t find_object_pos(const unsigned char *sha1)
140{
141 struct object_entry *entry = packlist_find(writer.to_pack, sha1, NULL);
142
143 if (!entry) {
144 die("Failed to write bitmap index. Packfile doesn't have full closure "
145 "(object %s is missing)", sha1_to_hex(sha1));
146 }
147
148 return entry->in_pack_pos;
149}
150
de1e67d0 151static void show_object(struct object *object, const char *name, void *data)
7cc8f971
VM
152{
153 struct bitmap *base = data;
ed1c9977 154 bitmap_set(base, find_object_pos(object->oid.hash));
7cc8f971
VM
155 mark_as_seen(object);
156}
157
158static void show_commit(struct commit *commit, void *data)
159{
160 mark_as_seen((struct object *)commit);
161}
162
163static int
164add_to_include_set(struct bitmap *base, struct commit *commit)
165{
166 khiter_t hash_pos;
ed1c9977 167 uint32_t bitmap_pos = find_object_pos(commit->object.oid.hash);
7cc8f971
VM
168
169 if (bitmap_get(base, bitmap_pos))
170 return 0;
171
ed1c9977 172 hash_pos = kh_get_sha1(writer.bitmaps, commit->object.oid.hash);
7cc8f971
VM
173 if (hash_pos < kh_end(writer.bitmaps)) {
174 struct bitmapped_commit *bc = kh_value(writer.bitmaps, hash_pos);
175 bitmap_or_ewah(base, bc->bitmap);
176 return 0;
177 }
178
179 bitmap_set(base, bitmap_pos);
180 return 1;
181}
182
183static int
184should_include(struct commit *commit, void *_data)
185{
186 struct bitmap *base = _data;
187
188 if (!add_to_include_set(base, commit)) {
189 struct commit_list *parent = commit->parents;
190
191 mark_as_seen((struct object *)commit);
192
193 while (parent) {
194 parent->item->object.flags |= SEEN;
195 mark_as_seen((struct object *)parent->item);
196 parent = parent->next;
197 }
198
199 return 0;
200 }
201
202 return 1;
203}
204
205static void compute_xor_offsets(void)
206{
207 static const int MAX_XOR_OFFSET_SEARCH = 10;
208
209 int i, next = 0;
210
211 while (next < writer.selected_nr) {
212 struct bitmapped_commit *stored = &writer.selected[next];
213
214 int best_offset = 0;
215 struct ewah_bitmap *best_bitmap = stored->bitmap;
216 struct ewah_bitmap *test_xor;
217
218 for (i = 1; i <= MAX_XOR_OFFSET_SEARCH; ++i) {
219 int curr = next - i;
220
221 if (curr < 0)
222 break;
223
224 test_xor = ewah_pool_new();
225 ewah_xor(writer.selected[curr].bitmap, stored->bitmap, test_xor);
226
227 if (test_xor->buffer_size < best_bitmap->buffer_size) {
228 if (best_bitmap != stored->bitmap)
229 ewah_pool_free(best_bitmap);
230
231 best_bitmap = test_xor;
232 best_offset = i;
233 } else {
234 ewah_pool_free(test_xor);
235 }
236 }
237
238 stored->xor_offset = best_offset;
239 stored->write_as = best_bitmap;
240
241 next++;
242 }
243}
244
245void bitmap_writer_build(struct packing_data *to_pack)
246{
247 static const double REUSE_BITMAP_THRESHOLD = 0.2;
248
249 int i, reuse_after, need_reset;
250 struct bitmap *base = bitmap_new();
251 struct rev_info revs;
252
253 writer.bitmaps = kh_init_sha1();
254 writer.to_pack = to_pack;
255
256 if (writer.show_progress)
257 writer.progress = start_progress("Building bitmaps", writer.selected_nr);
258
259 init_revisions(&revs, NULL);
260 revs.tag_objects = 1;
261 revs.tree_objects = 1;
262 revs.blob_objects = 1;
263 revs.no_walk = 0;
264
265 revs.include_check = should_include;
266 reset_revision_walk();
267
268 reuse_after = writer.selected_nr * REUSE_BITMAP_THRESHOLD;
269 need_reset = 0;
270
271 for (i = writer.selected_nr - 1; i >= 0; --i) {
272 struct bitmapped_commit *stored;
273 struct object *object;
274
275 khiter_t hash_pos;
276 int hash_ret;
277
278 stored = &writer.selected[i];
279 object = (struct object *)stored->commit;
280
281 if (stored->bitmap == NULL) {
282 if (i < writer.selected_nr - 1 &&
283 (need_reset ||
284 !in_merge_bases(writer.selected[i + 1].commit,
285 stored->commit))) {
286 bitmap_reset(base);
287 reset_all_seen();
288 }
289
290 add_pending_object(&revs, object, "");
291 revs.include_check_data = base;
292
293 if (prepare_revision_walk(&revs))
294 die("revision walk setup failed");
295
296 traverse_commit_list(&revs, show_commit, show_object, base);
297
298 revs.pending.nr = 0;
299 revs.pending.alloc = 0;
300 revs.pending.objects = NULL;
301
302 stored->bitmap = bitmap_to_ewah(base);
303 need_reset = 0;
304 } else
305 need_reset = 1;
306
307 if (i >= reuse_after)
308 stored->flags |= BITMAP_FLAG_REUSE;
309
ed1c9977 310 hash_pos = kh_put_sha1(writer.bitmaps, object->oid.hash, &hash_ret);
7cc8f971
VM
311 if (hash_ret == 0)
312 die("Duplicate entry when writing index: %s",
f2fd0760 313 oid_to_hex(&object->oid));
7cc8f971
VM
314
315 kh_value(writer.bitmaps, hash_pos) = stored;
316 display_progress(writer.progress, writer.selected_nr - i);
317 }
318
319 bitmap_free(base);
320 stop_progress(&writer.progress);
321
322 compute_xor_offsets();
323}
324
325/**
326 * Select the commits that will be bitmapped
327 */
328static inline unsigned int next_commit_index(unsigned int idx)
329{
330 static const unsigned int MIN_COMMITS = 100;
331 static const unsigned int MAX_COMMITS = 5000;
332
333 static const unsigned int MUST_REGION = 100;
334 static const unsigned int MIN_REGION = 20000;
335
336 unsigned int offset, next;
337
338 if (idx <= MUST_REGION)
339 return 0;
340
341 if (idx <= MIN_REGION) {
342 offset = idx - MUST_REGION;
343 return (offset < MIN_COMMITS) ? offset : MIN_COMMITS;
344 }
345
346 offset = idx - MIN_REGION;
347 next = (offset < MAX_COMMITS) ? offset : MAX_COMMITS;
348
349 return (next > MIN_COMMITS) ? next : MIN_COMMITS;
350}
351
352static int date_compare(const void *_a, const void *_b)
353{
354 struct commit *a = *(struct commit **)_a;
355 struct commit *b = *(struct commit **)_b;
356 return (long)b->date - (long)a->date;
357}
358
359void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack)
360{
361 if (prepare_bitmap_git() < 0)
362 return;
363
364 writer.reused = kh_init_sha1();
365 rebuild_existing_bitmaps(to_pack, writer.reused, writer.show_progress);
366}
367
368static struct ewah_bitmap *find_reused_bitmap(const unsigned char *sha1)
369{
370 khiter_t hash_pos;
371
372 if (!writer.reused)
373 return NULL;
374
375 hash_pos = kh_get_sha1(writer.reused, sha1);
376 if (hash_pos >= kh_end(writer.reused))
377 return NULL;
378
379 return kh_value(writer.reused, hash_pos);
380}
381
382void bitmap_writer_select_commits(struct commit **indexed_commits,
383 unsigned int indexed_commits_nr,
384 int max_bitmaps)
385{
386 unsigned int i = 0, j, next;
387
9ed0d8d6 388 QSORT(indexed_commits, indexed_commits_nr, date_compare);
7cc8f971
VM
389
390 if (writer.show_progress)
391 writer.progress = start_progress("Selecting bitmap commits", 0);
392
393 if (indexed_commits_nr < 100) {
394 for (i = 0; i < indexed_commits_nr; ++i)
395 push_bitmapped_commit(indexed_commits[i], NULL);
396 return;
397 }
398
399 for (;;) {
400 struct ewah_bitmap *reused_bitmap = NULL;
401 struct commit *chosen = NULL;
402
403 next = next_commit_index(i);
404
405 if (i + next >= indexed_commits_nr)
406 break;
407
408 if (max_bitmaps > 0 && writer.selected_nr >= max_bitmaps) {
409 writer.selected_nr = max_bitmaps;
410 break;
411 }
412
413 if (next == 0) {
414 chosen = indexed_commits[i];
ed1c9977 415 reused_bitmap = find_reused_bitmap(chosen->object.oid.hash);
7cc8f971
VM
416 } else {
417 chosen = indexed_commits[i + next];
418
419 for (j = 0; j <= next; ++j) {
420 struct commit *cm = indexed_commits[i + j];
421
ed1c9977 422 reused_bitmap = find_reused_bitmap(cm->object.oid.hash);
7cc8f971
VM
423 if (reused_bitmap || (cm->object.flags & NEEDS_BITMAP) != 0) {
424 chosen = cm;
425 break;
426 }
427
428 if (cm->parents && cm->parents->next)
429 chosen = cm;
430 }
431 }
432
433 push_bitmapped_commit(chosen, reused_bitmap);
434
435 i += next + 1;
436 display_progress(writer.progress, i);
437 }
438
439 stop_progress(&writer.progress);
440}
441
442
443static int sha1write_ewah_helper(void *f, const void *buf, size_t len)
444{
445 /* sha1write will die on error */
446 sha1write(f, buf, len);
447 return len;
448}
449
450/**
451 * Write the bitmap index to disk
452 */
453static inline void dump_bitmap(struct sha1file *f, struct ewah_bitmap *bitmap)
454{
455 if (ewah_serialize_to(bitmap, sha1write_ewah_helper, f) < 0)
456 die("Failed to write bitmap index");
457}
458
459static const unsigned char *sha1_access(size_t pos, void *table)
460{
461 struct pack_idx_entry **index = table;
462 return index[pos]->sha1;
463}
464
465static void write_selected_commits_v1(struct sha1file *f,
466 struct pack_idx_entry **index,
467 uint32_t index_nr)
468{
469 int i;
470
471 for (i = 0; i < writer.selected_nr; ++i) {
472 struct bitmapped_commit *stored = &writer.selected[i];
7cc8f971
VM
473
474 int commit_pos =
ed1c9977 475 sha1_pos(stored->commit->object.oid.hash, index, index_nr, sha1_access);
7cc8f971
VM
476
477 if (commit_pos < 0)
478 die("BUG: trying to write commit not in index");
479
b5007211
KB
480 sha1write_be32(f, commit_pos);
481 sha1write_u8(f, stored->xor_offset);
482 sha1write_u8(f, stored->flags);
7cc8f971 483
7cc8f971
VM
484 dump_bitmap(f, stored->write_as);
485 }
486}
487
ae4f07fb
VM
488static void write_hash_cache(struct sha1file *f,
489 struct pack_idx_entry **index,
490 uint32_t index_nr)
491{
492 uint32_t i;
493
494 for (i = 0; i < index_nr; ++i) {
495 struct object_entry *entry = (struct object_entry *)index[i];
496 uint32_t hash_value = htonl(entry->hash);
497 sha1write(f, &hash_value, sizeof(hash_value));
498 }
499}
500
7cc8f971
VM
501void bitmap_writer_set_checksum(unsigned char *sha1)
502{
503 hashcpy(writer.pack_checksum, sha1);
504}
505
506void bitmap_writer_finish(struct pack_idx_entry **index,
507 uint32_t index_nr,
ae4f07fb
VM
508 const char *filename,
509 uint16_t options)
7cc8f971
VM
510{
511 static char tmp_file[PATH_MAX];
512 static uint16_t default_version = 1;
513 static uint16_t flags = BITMAP_OPT_FULL_DAG;
514 struct sha1file *f;
515
516 struct bitmap_disk_header header;
517
518 int fd = odb_mkstemp(tmp_file, sizeof(tmp_file), "pack/tmp_bitmap_XXXXXX");
519
7cc8f971
VM
520 f = sha1fd(fd, tmp_file);
521
522 memcpy(header.magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE));
523 header.version = htons(default_version);
ae4f07fb 524 header.options = htons(flags | options);
7cc8f971 525 header.entry_count = htonl(writer.selected_nr);
50546b15 526 hashcpy(header.checksum, writer.pack_checksum);
7cc8f971
VM
527
528 sha1write(f, &header, sizeof(header));
529 dump_bitmap(f, writer.commits);
530 dump_bitmap(f, writer.trees);
531 dump_bitmap(f, writer.blobs);
532 dump_bitmap(f, writer.tags);
533 write_selected_commits_v1(f, index, index_nr);
534
ae4f07fb
VM
535 if (options & BITMAP_OPT_HASH_CACHE)
536 write_hash_cache(f, index, index_nr);
537
7cc8f971
VM
538 sha1close(f, NULL, CSUM_FSYNC);
539
540 if (adjust_shared_perm(tmp_file))
541 die_errno("unable to make temporary bitmap file readable");
542
543 if (rename(tmp_file, filename))
544 die_errno("unable to rename temporary bitmap file to '%s'", filename);
545}