]>
Commit | Line | Data |
---|---|---|
c283ab21 LS |
1 | /* |
2 | * | |
3 | * Copyright 2005, Lukas Sandstrom <lukass@etek.chalmers.se> | |
4 | * | |
5 | * This file is licensed under the GPL v2. | |
6 | * | |
7 | */ | |
8 | ||
9 | #include "cache.h" | |
10 | ||
9bc0f32c | 11 | static const char pack_redundant_usage[] = |
1c3039e8 | 12 | "git-pack-redundant [ --verbose ] [ --alt-odb ] < --all | <.pack filename> ...>"; |
c283ab21 | 13 | |
1c3039e8 | 14 | int load_all_packs = 0, verbose = 0, alt_odb = 0; |
c283ab21 LS |
15 | |
16 | struct llist_item { | |
17 | struct llist_item *next; | |
18 | char *sha1; | |
19 | }; | |
20 | struct llist { | |
21 | struct llist_item *front; | |
22 | struct llist_item *back; | |
23 | size_t size; | |
1c3039e8 | 24 | } *all_objects; /* all objects which must be present in local packfiles */ |
c283ab21 LS |
25 | |
26 | struct pack_list { | |
27 | struct pack_list *next; | |
28 | struct packed_git *pack; | |
29 | struct llist *unique_objects; | |
30 | struct llist *all_objects; | |
1c3039e8 | 31 | } *local_packs = NULL, *altodb_packs = NULL; |
c283ab21 LS |
32 | |
33 | struct pll { | |
34 | struct pll *next; | |
35 | struct pack_list *pl; | |
36 | }; | |
37 | ||
38 | inline void llist_free(struct llist *list) | |
39 | { | |
40 | while((list->back = list->front)) { | |
41 | list->front = list->front->next; | |
42 | free(list->back); | |
43 | } | |
44 | free(list); | |
45 | } | |
46 | ||
47 | inline void llist_init(struct llist **list) | |
48 | { | |
49 | *list = xmalloc(sizeof(struct llist)); | |
50 | (*list)->front = (*list)->back = NULL; | |
51 | (*list)->size = 0; | |
52 | } | |
53 | ||
54 | struct llist * llist_copy(struct llist *list) | |
55 | { | |
56 | struct llist *ret; | |
57 | struct llist_item *new, *old, *prev; | |
58 | ||
59 | llist_init(&ret); | |
60 | ||
61 | if ((ret->size = list->size) == 0) | |
62 | return ret; | |
63 | ||
64 | new = ret->front = xmalloc(sizeof(struct llist_item)); | |
65 | new->sha1 = list->front->sha1; | |
66 | ||
67 | old = list->front->next; | |
68 | while (old) { | |
69 | prev = new; | |
70 | new = xmalloc(sizeof(struct llist_item)); | |
71 | prev->next = new; | |
72 | new->sha1 = old->sha1; | |
73 | old = old->next; | |
74 | } | |
75 | new->next = NULL; | |
76 | ret->back = new; | |
77 | ||
78 | return ret; | |
79 | } | |
80 | ||
81 | inline struct llist_item * llist_insert(struct llist *list, | |
82 | struct llist_item *after, char *sha1) | |
83 | { | |
84 | struct llist_item *new = xmalloc(sizeof(struct llist_item)); | |
85 | new->sha1 = sha1; | |
86 | new->next = NULL; | |
87 | ||
88 | if (after != NULL) { | |
89 | new->next = after->next; | |
90 | after->next = new; | |
91 | if (after == list->back) | |
92 | list->back = new; | |
93 | } else {/* insert in front */ | |
94 | if (list->size == 0) | |
95 | list->back = new; | |
96 | else | |
97 | new->next = list->front; | |
98 | list->front = new; | |
99 | } | |
100 | list->size++; | |
101 | return new; | |
102 | } | |
103 | ||
104 | inline struct llist_item * llist_insert_back(struct llist *list, char *sha1) | |
105 | { | |
106 | return llist_insert(list, list->back, sha1); | |
107 | } | |
108 | ||
109 | inline struct llist_item * llist_insert_sorted_unique(struct llist *list, | |
110 | char *sha1, struct llist_item *hint) | |
111 | { | |
112 | struct llist_item *prev = NULL, *l; | |
113 | ||
114 | l = (hint == NULL) ? list->front : hint; | |
115 | while (l) { | |
116 | int cmp = memcmp(l->sha1, sha1, 20); | |
117 | if (cmp > 0) { /* we insert before this entry */ | |
118 | return llist_insert(list, prev, sha1); | |
119 | } | |
120 | if(!cmp) { /* already exists */ | |
121 | return l; | |
122 | } | |
123 | prev = l; | |
124 | l = l->next; | |
125 | } | |
126 | /* insert at the end */ | |
127 | return llist_insert_back(list, sha1); | |
128 | } | |
129 | ||
130 | /* computes A\B */ | |
1c3039e8 LS |
131 | void llist_sorted_difference_inplace(struct llist *A, |
132 | struct llist *B) | |
c283ab21 | 133 | { |
1c3039e8 | 134 | struct llist_item *prev, *a, *b, *x; |
c283ab21 | 135 | |
1c3039e8 LS |
136 | prev = a = A->front; |
137 | b = B->front; | |
138 | ||
139 | while (a != NULL && b != NULL) { | |
140 | int cmp = memcmp(a->sha1, b->sha1, 20); | |
c283ab21 | 141 | if (!cmp) { |
1c3039e8 LS |
142 | x = a; |
143 | if (a == A->front) | |
144 | A->front = a->next; | |
145 | a = prev->next = a->next; | |
146 | ||
147 | if (a == NULL) /* end of list */ | |
148 | A->back = prev; | |
149 | A->size--; | |
150 | free(x); | |
151 | b = b->next; | |
152 | } else | |
153 | if (cmp > 0) | |
154 | b = b->next; | |
155 | else { | |
156 | prev = a; | |
157 | a = a->next; | |
158 | } | |
c283ab21 | 159 | } |
c283ab21 LS |
160 | } |
161 | ||
162 | /* returns a pointer to an item in front of sha1 */ | |
163 | inline struct llist_item * llist_sorted_remove(struct llist *list, char *sha1, | |
164 | struct llist_item *hint) | |
165 | { | |
166 | struct llist_item *prev, *l; | |
167 | ||
168 | redo_from_start: | |
169 | l = (hint == NULL) ? list->front : hint; | |
170 | prev = NULL; | |
171 | while (l) { | |
172 | int cmp = memcmp(l->sha1, sha1, 20); | |
173 | if (cmp > 0) /* not in list, since sorted */ | |
174 | return prev; | |
175 | if(!cmp) { /* found */ | |
176 | if (prev == NULL) { | |
177 | if (hint != NULL && hint != list->front) { | |
178 | /* we don't know the previous element */ | |
179 | hint = NULL; | |
180 | goto redo_from_start; | |
181 | } | |
182 | list->front = l->next; | |
183 | } else | |
184 | prev->next = l->next; | |
185 | if (l == list->back) | |
186 | list->back = prev; | |
187 | free(l); | |
188 | list->size--; | |
189 | return prev; | |
190 | } | |
191 | prev = l; | |
192 | l = l->next; | |
193 | } | |
194 | return prev; | |
195 | } | |
196 | ||
197 | inline struct pack_list * pack_list_insert(struct pack_list **pl, | |
198 | struct pack_list *entry) | |
199 | { | |
200 | struct pack_list *p = xmalloc(sizeof(struct pack_list)); | |
201 | memcpy(p, entry, sizeof(struct pack_list)); | |
202 | p->next = *pl; | |
203 | *pl = p; | |
204 | return p; | |
205 | } | |
206 | ||
1c3039e8 LS |
207 | inline size_t pack_list_size(struct pack_list *pl) |
208 | { | |
209 | size_t ret = 0; | |
210 | while(pl) { | |
211 | ret++; | |
212 | pl = pl->next; | |
213 | } | |
214 | return ret; | |
215 | } | |
216 | ||
c283ab21 LS |
217 | struct pack_list * pack_list_difference(struct pack_list *A, |
218 | struct pack_list *B) | |
219 | { | |
220 | struct pack_list *ret, *pl; | |
221 | ||
222 | if (A == NULL) | |
223 | return NULL; | |
224 | ||
225 | pl = B; | |
226 | while (pl != NULL) { | |
227 | if (A->pack == pl->pack) | |
228 | return pack_list_difference(A->next, B); | |
229 | pl = pl->next; | |
230 | } | |
231 | ret = xmalloc(sizeof(struct pack_list)); | |
232 | memcpy(ret, A, sizeof(struct pack_list)); | |
233 | ret->next = pack_list_difference(A->next, B); | |
234 | return ret; | |
235 | } | |
236 | ||
237 | void cmp_two_packs(struct pack_list *p1, struct pack_list *p2) | |
238 | { | |
239 | int p1_off, p2_off; | |
240 | void *p1_base, *p2_base; | |
241 | struct llist_item *p1_hint = NULL, *p2_hint = NULL; | |
242 | ||
243 | p1_off = p2_off = 256 * 4 + 4; | |
244 | p1_base = (void *)p1->pack->index_base; | |
245 | p2_base = (void *)p2->pack->index_base; | |
246 | ||
247 | while (p1_off <= p1->pack->index_size - 3 * 20 && | |
248 | p2_off <= p2->pack->index_size - 3 * 20) | |
249 | { | |
250 | int cmp = memcmp(p1_base + p1_off, p2_base + p2_off, 20); | |
251 | /* cmp ~ p1 - p2 */ | |
252 | if (cmp == 0) { | |
253 | p1_hint = llist_sorted_remove(p1->unique_objects, | |
254 | p1_base + p1_off, p1_hint); | |
255 | p2_hint = llist_sorted_remove(p2->unique_objects, | |
256 | p1_base + p1_off, p2_hint); | |
257 | p1_off+=24; | |
258 | p2_off+=24; | |
259 | continue; | |
260 | } | |
261 | if (cmp < 0) { /* p1 has the object, p2 doesn't */ | |
262 | p1_off+=24; | |
263 | } else { /* p2 has the object, p1 doesn't */ | |
264 | p2_off+=24; | |
265 | } | |
266 | } | |
267 | } | |
268 | ||
269 | /* all the permutations have to be free()d at the same time, | |
270 | * since they refer to each other | |
271 | */ | |
272 | struct pll * get_all_permutations(struct pack_list *list) | |
273 | { | |
274 | struct pll *subset, *pll, *new_pll = NULL; /*silence warning*/ | |
275 | ||
276 | if (list == NULL) | |
277 | return NULL; | |
278 | ||
279 | if (list->next == NULL) { | |
280 | new_pll = xmalloc(sizeof(struct pll)); | |
281 | new_pll->next = NULL; | |
282 | new_pll->pl = list; | |
283 | return new_pll; | |
284 | } | |
285 | ||
286 | pll = subset = get_all_permutations(list->next); | |
287 | while (pll) { | |
288 | new_pll = xmalloc(sizeof(struct pll)); | |
289 | new_pll->next = pll->next; | |
290 | pll->next = new_pll; | |
291 | ||
292 | new_pll->pl = xmalloc(sizeof(struct pack_list)); | |
293 | memcpy(new_pll->pl, list, sizeof(struct pack_list)); | |
294 | new_pll->pl->next = pll->pl; | |
295 | ||
296 | pll = new_pll->next; | |
297 | } | |
298 | /* add ourself to the end */ | |
299 | new_pll->next = xmalloc(sizeof(struct pll)); | |
300 | new_pll->next->pl = xmalloc(sizeof(struct pack_list)); | |
301 | new_pll->next->next = NULL; | |
302 | memcpy(new_pll->next->pl, list, sizeof(struct pack_list)); | |
303 | new_pll->next->pl->next = NULL; | |
304 | ||
305 | return subset; | |
306 | } | |
307 | ||
308 | int is_superset(struct pack_list *pl, struct llist *list) | |
309 | { | |
1c3039e8 | 310 | struct llist *diff; |
c283ab21 LS |
311 | |
312 | diff = llist_copy(list); | |
313 | ||
314 | while (pl) { | |
1c3039e8 LS |
315 | llist_sorted_difference_inplace(diff, |
316 | pl->all_objects); | |
c283ab21 LS |
317 | if (diff->size == 0) { /* we're done */ |
318 | llist_free(diff); | |
319 | return 1; | |
320 | } | |
321 | pl = pl->next; | |
322 | } | |
323 | llist_free(diff); | |
324 | return 0; | |
325 | } | |
326 | ||
327 | size_t sizeof_union(struct packed_git *p1, struct packed_git *p2) | |
328 | { | |
329 | size_t ret = 0; | |
330 | int p1_off, p2_off; | |
331 | void *p1_base, *p2_base; | |
332 | ||
333 | p1_off = p2_off = 256 * 4 + 4; | |
334 | p1_base = (void *)p1->index_base; | |
335 | p2_base = (void *)p2->index_base; | |
336 | ||
337 | while (p1_off <= p1->index_size - 3 * 20 && | |
338 | p2_off <= p2->index_size - 3 * 20) | |
339 | { | |
340 | int cmp = memcmp(p1_base + p1_off, p2_base + p2_off, 20); | |
341 | /* cmp ~ p1 - p2 */ | |
342 | if (cmp == 0) { | |
343 | ret++; | |
344 | p1_off+=24; | |
345 | p2_off+=24; | |
346 | continue; | |
347 | } | |
348 | if (cmp < 0) { /* p1 has the object, p2 doesn't */ | |
349 | p1_off+=24; | |
350 | } else { /* p2 has the object, p1 doesn't */ | |
351 | p2_off+=24; | |
352 | } | |
353 | } | |
354 | return ret; | |
355 | } | |
356 | ||
357 | /* another O(n^2) function ... */ | |
358 | size_t get_pack_redundancy(struct pack_list *pl) | |
359 | { | |
360 | struct pack_list *subset; | |
1c3039e8 LS |
361 | |
362 | if (pl == NULL) | |
363 | return 0; | |
364 | ||
c283ab21 LS |
365 | size_t ret = 0; |
366 | while ((subset = pl->next)) { | |
367 | while(subset) { | |
368 | ret += sizeof_union(pl->pack, subset->pack); | |
369 | subset = subset->next; | |
370 | } | |
371 | pl = pl->next; | |
372 | } | |
373 | return ret; | |
374 | } | |
375 | ||
376 | inline size_t pack_set_bytecount(struct pack_list *pl) | |
377 | { | |
378 | size_t ret = 0; | |
379 | while (pl) { | |
380 | ret += pl->pack->pack_size; | |
381 | ret += pl->pack->index_size; | |
382 | pl = pl->next; | |
383 | } | |
384 | return ret; | |
385 | } | |
386 | ||
387 | void minimize(struct pack_list **min) | |
388 | { | |
389 | struct pack_list *pl, *unique = NULL, | |
390 | *non_unique = NULL, *min_perm = NULL; | |
391 | struct pll *perm, *perm_all, *perm_ok = NULL, *new_perm; | |
1c3039e8 | 392 | struct llist *missing; |
c283ab21 LS |
393 | size_t min_perm_size = (size_t)-1, perm_size; |
394 | ||
1c3039e8 | 395 | pl = local_packs; |
c283ab21 LS |
396 | while (pl) { |
397 | if(pl->unique_objects->size) | |
398 | pack_list_insert(&unique, pl); | |
399 | else | |
400 | pack_list_insert(&non_unique, pl); | |
401 | pl = pl->next; | |
402 | } | |
403 | /* find out which objects are missing from the set of unique packs */ | |
404 | missing = llist_copy(all_objects); | |
405 | pl = unique; | |
406 | while (pl) { | |
1c3039e8 LS |
407 | llist_sorted_difference_inplace(missing, |
408 | pl->all_objects); | |
c283ab21 LS |
409 | pl = pl->next; |
410 | } | |
411 | ||
1c3039e8 | 412 | /* return if there are no objects missing from the unique set */ |
c283ab21 LS |
413 | if (missing->size == 0) { |
414 | *min = unique; | |
415 | return; | |
416 | } | |
417 | ||
418 | /* find the permutations which contain all missing objects */ | |
419 | perm_all = perm = get_all_permutations(non_unique); | |
420 | while (perm) { | |
421 | if (is_superset(perm->pl, missing)) { | |
422 | new_perm = xmalloc(sizeof(struct pll)); | |
423 | new_perm->pl = perm->pl; | |
424 | new_perm->next = perm_ok; | |
425 | perm_ok = new_perm; | |
426 | } | |
427 | perm = perm->next; | |
428 | } | |
429 | ||
430 | if (perm_ok == NULL) | |
431 | die("Internal error: No complete sets found!\n"); | |
432 | ||
433 | /* find the permutation with the smallest size */ | |
434 | perm = perm_ok; | |
435 | while (perm) { | |
436 | perm_size = pack_set_bytecount(perm->pl); | |
437 | if (min_perm_size > perm_size) { | |
438 | min_perm_size = perm_size; | |
439 | min_perm = perm->pl; | |
440 | } | |
441 | perm = perm->next; | |
442 | } | |
443 | *min = min_perm; | |
444 | /* add the unique packs to the list */ | |
445 | pl = unique; | |
446 | while(pl) { | |
447 | pack_list_insert(min, pl); | |
448 | pl = pl->next; | |
449 | } | |
450 | } | |
451 | ||
452 | void load_all_objects() | |
453 | { | |
1c3039e8 | 454 | struct pack_list *pl = local_packs; |
c283ab21 LS |
455 | struct llist_item *hint, *l; |
456 | int i; | |
457 | ||
458 | llist_init(&all_objects); | |
459 | ||
460 | while (pl) { | |
461 | i = 0; | |
462 | hint = NULL; | |
463 | l = pl->all_objects->front; | |
464 | while (l) { | |
465 | hint = llist_insert_sorted_unique(all_objects, | |
466 | l->sha1, hint); | |
467 | l = l->next; | |
468 | } | |
469 | pl = pl->next; | |
470 | } | |
1c3039e8 LS |
471 | /* remove objects present in remote packs */ |
472 | pl = altodb_packs; | |
473 | while (pl) { | |
474 | llist_sorted_difference_inplace(all_objects, pl->all_objects); | |
475 | pl = pl->next; | |
476 | } | |
c283ab21 LS |
477 | } |
478 | ||
479 | /* this scales like O(n^2) */ | |
480 | void cmp_packs() | |
481 | { | |
1c3039e8 | 482 | struct pack_list *subset, *pl = local_packs; |
c283ab21 | 483 | |
1c3039e8 | 484 | while ((subset = pl)) { |
c283ab21 | 485 | while((subset = subset->next)) |
1c3039e8 LS |
486 | cmp_two_packs(pl, subset); |
487 | pl = pl->next; | |
488 | } | |
489 | ||
490 | pl = altodb_packs; | |
491 | while (pl) { | |
492 | subset = local_packs; | |
493 | while (subset) { | |
494 | llist_sorted_difference_inplace(subset->unique_objects, | |
495 | pl->all_objects); | |
496 | subset = subset->next; | |
497 | } | |
498 | pl = pl->next; | |
c283ab21 LS |
499 | } |
500 | } | |
501 | ||
502 | struct pack_list * add_pack(struct packed_git *p) | |
503 | { | |
504 | struct pack_list l; | |
505 | size_t off; | |
506 | void *base; | |
507 | ||
508 | l.pack = p; | |
509 | llist_init(&l.all_objects); | |
510 | ||
511 | off = 256 * 4 + 4; | |
512 | base = (void *)p->index_base; | |
513 | while (off <= p->index_size - 3 * 20) { | |
514 | llist_insert_back(l.all_objects, base + off); | |
515 | off+=24; | |
516 | } | |
517 | /* this list will be pruned in cmp_two_packs later */ | |
518 | l.unique_objects = llist_copy(l.all_objects); | |
1c3039e8 LS |
519 | if (p->pack_local) |
520 | return pack_list_insert(&local_packs, &l); | |
521 | else | |
522 | return alt_odb ? pack_list_insert(&altodb_packs, &l) : NULL; | |
c283ab21 LS |
523 | } |
524 | ||
525 | struct pack_list * add_pack_file(char *filename) | |
526 | { | |
527 | struct packed_git *p = packed_git; | |
528 | ||
529 | if (strlen(filename) < 40) | |
530 | die("Bad pack filename: %s\n", filename); | |
531 | ||
532 | while (p) { | |
533 | if (strstr(p->pack_name, filename)) | |
c283ab21 LS |
534 | return add_pack(p); |
535 | p = p->next; | |
536 | } | |
537 | die("Filename %s not found in packed_git\n", filename); | |
538 | } | |
539 | ||
540 | void load_all() | |
541 | { | |
542 | struct packed_git *p = packed_git; | |
543 | ||
544 | while (p) { | |
1c3039e8 | 545 | add_pack(p); |
c283ab21 LS |
546 | p = p->next; |
547 | } | |
548 | } | |
549 | ||
550 | int main(int argc, char **argv) | |
551 | { | |
552 | int i; | |
553 | struct pack_list *min, *red, *pl; | |
554 | ||
555 | for (i = 1; i < argc; i++) { | |
556 | const char *arg = argv[i]; | |
9bc0f32c LS |
557 | if(!strcmp(arg, "--")) { |
558 | i++; | |
c283ab21 | 559 | break; |
9bc0f32c | 560 | } |
1c3039e8 LS |
561 | if(!strcmp(arg, "--all")) { |
562 | load_all_packs = 1; | |
c283ab21 LS |
563 | continue; |
564 | } | |
1c3039e8 | 565 | if(!strcmp(arg, "--verbose")) { |
c283ab21 LS |
566 | verbose = 1; |
567 | continue; | |
568 | } | |
1c3039e8 LS |
569 | if(!strcmp(arg, "--alt-odb")) { |
570 | alt_odb = 1; | |
571 | continue; | |
572 | } | |
c283ab21 | 573 | if(*arg == '-') |
9bc0f32c | 574 | usage(pack_redundant_usage); |
c283ab21 LS |
575 | else |
576 | break; | |
577 | } | |
578 | ||
579 | prepare_packed_git(); | |
580 | ||
1c3039e8 | 581 | if (load_all_packs) |
c283ab21 LS |
582 | load_all(); |
583 | else | |
584 | while (*(argv + i) != NULL) | |
585 | add_pack_file(*(argv + i++)); | |
586 | ||
1c3039e8 | 587 | if (local_packs == NULL) |
c283ab21 LS |
588 | die("Zero packs found!\n"); |
589 | ||
590 | cmp_packs(); | |
591 | ||
592 | load_all_objects(); | |
593 | ||
594 | minimize(&min); | |
595 | if (verbose) { | |
abacbe41 KR |
596 | fprintf(stderr, "There are %lu packs available in alt-odbs.\n", |
597 | (unsigned long)pack_list_size(altodb_packs)); | |
c283ab21 LS |
598 | fprintf(stderr, "The smallest (bytewise) set of packs is:\n"); |
599 | pl = min; | |
600 | while (pl) { | |
601 | fprintf(stderr, "\t%s\n", pl->pack->pack_name); | |
602 | pl = pl->next; | |
603 | } | |
abacbe41 KR |
604 | fprintf(stderr, "containing %lu duplicate objects " |
605 | "with a total size of %lukb.\n", | |
606 | (unsigned long)get_pack_redundancy(min), | |
607 | (unsigned long)pack_set_bytecount(min)/1024); | |
608 | fprintf(stderr, "A total of %lu unique objects were considered.\n", | |
609 | (unsigned long)all_objects->size); | |
c283ab21 LS |
610 | fprintf(stderr, "Redundant packs (with indexes):\n"); |
611 | } | |
1c3039e8 | 612 | pl = red = pack_list_difference(local_packs, min); |
c283ab21 LS |
613 | while (pl) { |
614 | printf("%s\n%s\n", | |
1c3039e8 LS |
615 | sha1_pack_index_name(pl->pack->sha1), |
616 | pl->pack->pack_name); | |
c283ab21 LS |
617 | pl = pl->next; |
618 | } | |
619 | ||
620 | return 0; | |
621 | } |