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1 | /* | |
2 | * GIT - The information manager from hell | |
3 | * | |
4 | * Copyright (C) Linus Torvalds, 2005 | |
5 | * | |
6 | * This handles basic git sha1 object files - packing, unpacking, | |
7 | * creation etc. | |
8 | */ | |
9 | #include "cache.h" | |
10 | #include "delta.h" | |
11 | #include "pack.h" | |
12 | #include "blob.h" | |
13 | #include "commit.h" | |
14 | #include "run-command.h" | |
15 | #include "tag.h" | |
16 | #include "tree.h" | |
17 | #include "tree-walk.h" | |
18 | #include "refs.h" | |
19 | #include "pack-revindex.h" | |
20 | #include "sha1-lookup.h" | |
21 | ||
22 | #ifndef O_NOATIME | |
23 | #if defined(__linux__) && (defined(__i386__) || defined(__PPC__)) | |
24 | #define O_NOATIME 01000000 | |
25 | #else | |
26 | #define O_NOATIME 0 | |
27 | #endif | |
28 | #endif | |
29 | ||
30 | #define SZ_FMT PRIuMAX | |
31 | static inline uintmax_t sz_fmt(size_t s) { return s; } | |
32 | ||
33 | const unsigned char null_sha1[20]; | |
34 | ||
35 | /* | |
36 | * This is meant to hold a *small* number of objects that you would | |
37 | * want read_sha1_file() to be able to return, but yet you do not want | |
38 | * to write them into the object store (e.g. a browse-only | |
39 | * application). | |
40 | */ | |
41 | static struct cached_object { | |
42 | unsigned char sha1[20]; | |
43 | enum object_type type; | |
44 | void *buf; | |
45 | unsigned long size; | |
46 | } *cached_objects; | |
47 | static int cached_object_nr, cached_object_alloc; | |
48 | ||
49 | static struct cached_object empty_tree = { | |
50 | EMPTY_TREE_SHA1_BIN_LITERAL, | |
51 | OBJ_TREE, | |
52 | "", | |
53 | 0 | |
54 | }; | |
55 | ||
56 | static struct cached_object *find_cached_object(const unsigned char *sha1) | |
57 | { | |
58 | int i; | |
59 | struct cached_object *co = cached_objects; | |
60 | ||
61 | for (i = 0; i < cached_object_nr; i++, co++) { | |
62 | if (!hashcmp(co->sha1, sha1)) | |
63 | return co; | |
64 | } | |
65 | if (!hashcmp(sha1, empty_tree.sha1)) | |
66 | return &empty_tree; | |
67 | return NULL; | |
68 | } | |
69 | ||
70 | int mkdir_in_gitdir(const char *path) | |
71 | { | |
72 | if (mkdir(path, 0777)) { | |
73 | int saved_errno = errno; | |
74 | struct stat st; | |
75 | struct strbuf sb = STRBUF_INIT; | |
76 | ||
77 | if (errno != EEXIST) | |
78 | return -1; | |
79 | /* | |
80 | * Are we looking at a path in a symlinked worktree | |
81 | * whose original repository does not yet have it? | |
82 | * e.g. .git/rr-cache pointing at its original | |
83 | * repository in which the user hasn't performed any | |
84 | * conflict resolution yet? | |
85 | */ | |
86 | if (lstat(path, &st) || !S_ISLNK(st.st_mode) || | |
87 | strbuf_readlink(&sb, path, st.st_size) || | |
88 | !is_absolute_path(sb.buf) || | |
89 | mkdir(sb.buf, 0777)) { | |
90 | strbuf_release(&sb); | |
91 | errno = saved_errno; | |
92 | return -1; | |
93 | } | |
94 | strbuf_release(&sb); | |
95 | } | |
96 | return adjust_shared_perm(path); | |
97 | } | |
98 | ||
99 | int safe_create_leading_directories(char *path) | |
100 | { | |
101 | char *pos = path + offset_1st_component(path); | |
102 | struct stat st; | |
103 | ||
104 | while (pos) { | |
105 | pos = strchr(pos, '/'); | |
106 | if (!pos) | |
107 | break; | |
108 | while (*++pos == '/') | |
109 | ; | |
110 | if (!*pos) | |
111 | break; | |
112 | *--pos = '\0'; | |
113 | if (!stat(path, &st)) { | |
114 | /* path exists */ | |
115 | if (!S_ISDIR(st.st_mode)) { | |
116 | *pos = '/'; | |
117 | return -3; | |
118 | } | |
119 | } | |
120 | else if (mkdir(path, 0777)) { | |
121 | *pos = '/'; | |
122 | return -1; | |
123 | } | |
124 | else if (adjust_shared_perm(path)) { | |
125 | *pos = '/'; | |
126 | return -2; | |
127 | } | |
128 | *pos++ = '/'; | |
129 | } | |
130 | return 0; | |
131 | } | |
132 | ||
133 | int safe_create_leading_directories_const(const char *path) | |
134 | { | |
135 | /* path points to cache entries, so xstrdup before messing with it */ | |
136 | char *buf = xstrdup(path); | |
137 | int result = safe_create_leading_directories(buf); | |
138 | free(buf); | |
139 | return result; | |
140 | } | |
141 | ||
142 | static void fill_sha1_path(char *pathbuf, const unsigned char *sha1) | |
143 | { | |
144 | int i; | |
145 | for (i = 0; i < 20; i++) { | |
146 | static char hex[] = "0123456789abcdef"; | |
147 | unsigned int val = sha1[i]; | |
148 | char *pos = pathbuf + i*2 + (i > 0); | |
149 | *pos++ = hex[val >> 4]; | |
150 | *pos = hex[val & 0xf]; | |
151 | } | |
152 | } | |
153 | ||
154 | /* | |
155 | * NOTE! This returns a statically allocated buffer, so you have to be | |
156 | * careful about using it. Do an "xstrdup()" if you need to save the | |
157 | * filename. | |
158 | * | |
159 | * Also note that this returns the location for creating. Reading | |
160 | * SHA1 file can happen from any alternate directory listed in the | |
161 | * DB_ENVIRONMENT environment variable if it is not found in | |
162 | * the primary object database. | |
163 | */ | |
164 | char *sha1_file_name(const unsigned char *sha1) | |
165 | { | |
166 | static char buf[PATH_MAX]; | |
167 | const char *objdir; | |
168 | int len; | |
169 | ||
170 | objdir = get_object_directory(); | |
171 | len = strlen(objdir); | |
172 | ||
173 | /* '/' + sha1(2) + '/' + sha1(38) + '\0' */ | |
174 | if (len + 43 > PATH_MAX) | |
175 | die("insanely long object directory %s", objdir); | |
176 | memcpy(buf, objdir, len); | |
177 | buf[len] = '/'; | |
178 | buf[len+3] = '/'; | |
179 | buf[len+42] = '\0'; | |
180 | fill_sha1_path(buf + len + 1, sha1); | |
181 | return buf; | |
182 | } | |
183 | ||
184 | static char *sha1_get_pack_name(const unsigned char *sha1, | |
185 | char **name, char **base, const char *which) | |
186 | { | |
187 | static const char hex[] = "0123456789abcdef"; | |
188 | char *buf; | |
189 | int i; | |
190 | ||
191 | if (!*base) { | |
192 | const char *sha1_file_directory = get_object_directory(); | |
193 | int len = strlen(sha1_file_directory); | |
194 | *base = xmalloc(len + 60); | |
195 | sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s", | |
196 | sha1_file_directory, which); | |
197 | *name = *base + len + 11; | |
198 | } | |
199 | ||
200 | buf = *name; | |
201 | ||
202 | for (i = 0; i < 20; i++) { | |
203 | unsigned int val = *sha1++; | |
204 | *buf++ = hex[val >> 4]; | |
205 | *buf++ = hex[val & 0xf]; | |
206 | } | |
207 | ||
208 | return *base; | |
209 | } | |
210 | ||
211 | char *sha1_pack_name(const unsigned char *sha1) | |
212 | { | |
213 | static char *name, *base; | |
214 | ||
215 | return sha1_get_pack_name(sha1, &name, &base, "pack"); | |
216 | } | |
217 | ||
218 | char *sha1_pack_index_name(const unsigned char *sha1) | |
219 | { | |
220 | static char *name, *base; | |
221 | ||
222 | return sha1_get_pack_name(sha1, &name, &base, "idx"); | |
223 | } | |
224 | ||
225 | struct alternate_object_database *alt_odb_list; | |
226 | static struct alternate_object_database **alt_odb_tail; | |
227 | ||
228 | static void read_info_alternates(const char * alternates, int depth); | |
229 | static int git_open_noatime(const char *name); | |
230 | ||
231 | /* | |
232 | * Prepare alternate object database registry. | |
233 | * | |
234 | * The variable alt_odb_list points at the list of struct | |
235 | * alternate_object_database. The elements on this list come from | |
236 | * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT | |
237 | * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates, | |
238 | * whose contents is similar to that environment variable but can be | |
239 | * LF separated. Its base points at a statically allocated buffer that | |
240 | * contains "/the/directory/corresponding/to/.git/objects/...", while | |
241 | * its name points just after the slash at the end of ".git/objects/" | |
242 | * in the example above, and has enough space to hold 40-byte hex | |
243 | * SHA1, an extra slash for the first level indirection, and the | |
244 | * terminating NUL. | |
245 | */ | |
246 | static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth) | |
247 | { | |
248 | const char *objdir = get_object_directory(); | |
249 | struct alternate_object_database *ent; | |
250 | struct alternate_object_database *alt; | |
251 | /* 43 = 40-byte + 2 '/' + terminating NUL */ | |
252 | int pfxlen = len; | |
253 | int entlen = pfxlen + 43; | |
254 | int base_len = -1; | |
255 | ||
256 | if (!is_absolute_path(entry) && relative_base) { | |
257 | /* Relative alt-odb */ | |
258 | if (base_len < 0) | |
259 | base_len = strlen(relative_base) + 1; | |
260 | entlen += base_len; | |
261 | pfxlen += base_len; | |
262 | } | |
263 | ent = xmalloc(sizeof(*ent) + entlen); | |
264 | ||
265 | if (!is_absolute_path(entry) && relative_base) { | |
266 | memcpy(ent->base, relative_base, base_len - 1); | |
267 | ent->base[base_len - 1] = '/'; | |
268 | memcpy(ent->base + base_len, entry, len); | |
269 | } | |
270 | else | |
271 | memcpy(ent->base, entry, pfxlen); | |
272 | ||
273 | ent->name = ent->base + pfxlen + 1; | |
274 | ent->base[pfxlen + 3] = '/'; | |
275 | ent->base[pfxlen] = ent->base[entlen-1] = 0; | |
276 | ||
277 | /* Detect cases where alternate disappeared */ | |
278 | if (!is_directory(ent->base)) { | |
279 | error("object directory %s does not exist; " | |
280 | "check .git/objects/info/alternates.", | |
281 | ent->base); | |
282 | free(ent); | |
283 | return -1; | |
284 | } | |
285 | ||
286 | /* Prevent the common mistake of listing the same | |
287 | * thing twice, or object directory itself. | |
288 | */ | |
289 | for (alt = alt_odb_list; alt; alt = alt->next) { | |
290 | if (!memcmp(ent->base, alt->base, pfxlen)) { | |
291 | free(ent); | |
292 | return -1; | |
293 | } | |
294 | } | |
295 | if (!memcmp(ent->base, objdir, pfxlen)) { | |
296 | free(ent); | |
297 | return -1; | |
298 | } | |
299 | ||
300 | /* add the alternate entry */ | |
301 | *alt_odb_tail = ent; | |
302 | alt_odb_tail = &(ent->next); | |
303 | ent->next = NULL; | |
304 | ||
305 | /* recursively add alternates */ | |
306 | read_info_alternates(ent->base, depth + 1); | |
307 | ||
308 | ent->base[pfxlen] = '/'; | |
309 | ||
310 | return 0; | |
311 | } | |
312 | ||
313 | static void link_alt_odb_entries(const char *alt, const char *ep, int sep, | |
314 | const char *relative_base, int depth) | |
315 | { | |
316 | const char *cp, *last; | |
317 | ||
318 | if (depth > 5) { | |
319 | error("%s: ignoring alternate object stores, nesting too deep.", | |
320 | relative_base); | |
321 | return; | |
322 | } | |
323 | ||
324 | last = alt; | |
325 | while (last < ep) { | |
326 | cp = last; | |
327 | if (cp < ep && *cp == '#') { | |
328 | while (cp < ep && *cp != sep) | |
329 | cp++; | |
330 | last = cp + 1; | |
331 | continue; | |
332 | } | |
333 | while (cp < ep && *cp != sep) | |
334 | cp++; | |
335 | if (last != cp) { | |
336 | if (!is_absolute_path(last) && depth) { | |
337 | error("%s: ignoring relative alternate object store %s", | |
338 | relative_base, last); | |
339 | } else { | |
340 | link_alt_odb_entry(last, cp - last, | |
341 | relative_base, depth); | |
342 | } | |
343 | } | |
344 | while (cp < ep && *cp == sep) | |
345 | cp++; | |
346 | last = cp; | |
347 | } | |
348 | } | |
349 | ||
350 | static void read_info_alternates(const char * relative_base, int depth) | |
351 | { | |
352 | char *map; | |
353 | size_t mapsz; | |
354 | struct stat st; | |
355 | const char alt_file_name[] = "info/alternates"; | |
356 | /* Given that relative_base is no longer than PATH_MAX, | |
357 | ensure that "path" has enough space to append "/", the | |
358 | file name, "info/alternates", and a trailing NUL. */ | |
359 | char path[PATH_MAX + 1 + sizeof alt_file_name]; | |
360 | int fd; | |
361 | ||
362 | sprintf(path, "%s/%s", relative_base, alt_file_name); | |
363 | fd = git_open_noatime(path); | |
364 | if (fd < 0) | |
365 | return; | |
366 | if (fstat(fd, &st) || (st.st_size == 0)) { | |
367 | close(fd); | |
368 | return; | |
369 | } | |
370 | mapsz = xsize_t(st.st_size); | |
371 | map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0); | |
372 | close(fd); | |
373 | ||
374 | link_alt_odb_entries(map, map + mapsz, '\n', relative_base, depth); | |
375 | ||
376 | munmap(map, mapsz); | |
377 | } | |
378 | ||
379 | void add_to_alternates_file(const char *reference) | |
380 | { | |
381 | struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); | |
382 | int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR); | |
383 | char *alt = mkpath("%s/objects\n", reference); | |
384 | write_or_die(fd, alt, strlen(alt)); | |
385 | if (commit_lock_file(lock)) | |
386 | die("could not close alternates file"); | |
387 | if (alt_odb_tail) | |
388 | link_alt_odb_entries(alt, alt + strlen(alt), '\n', NULL, 0); | |
389 | } | |
390 | ||
391 | void foreach_alt_odb(alt_odb_fn fn, void *cb) | |
392 | { | |
393 | struct alternate_object_database *ent; | |
394 | ||
395 | prepare_alt_odb(); | |
396 | for (ent = alt_odb_list; ent; ent = ent->next) | |
397 | if (fn(ent, cb)) | |
398 | return; | |
399 | } | |
400 | ||
401 | void prepare_alt_odb(void) | |
402 | { | |
403 | const char *alt; | |
404 | ||
405 | if (alt_odb_tail) | |
406 | return; | |
407 | ||
408 | alt = getenv(ALTERNATE_DB_ENVIRONMENT); | |
409 | if (!alt) alt = ""; | |
410 | ||
411 | alt_odb_tail = &alt_odb_list; | |
412 | link_alt_odb_entries(alt, alt + strlen(alt), PATH_SEP, NULL, 0); | |
413 | ||
414 | read_info_alternates(get_object_directory(), 0); | |
415 | } | |
416 | ||
417 | static int has_loose_object_local(const unsigned char *sha1) | |
418 | { | |
419 | char *name = sha1_file_name(sha1); | |
420 | return !access(name, F_OK); | |
421 | } | |
422 | ||
423 | int has_loose_object_nonlocal(const unsigned char *sha1) | |
424 | { | |
425 | struct alternate_object_database *alt; | |
426 | prepare_alt_odb(); | |
427 | for (alt = alt_odb_list; alt; alt = alt->next) { | |
428 | fill_sha1_path(alt->name, sha1); | |
429 | if (!access(alt->base, F_OK)) | |
430 | return 1; | |
431 | } | |
432 | return 0; | |
433 | } | |
434 | ||
435 | static int has_loose_object(const unsigned char *sha1) | |
436 | { | |
437 | return has_loose_object_local(sha1) || | |
438 | has_loose_object_nonlocal(sha1); | |
439 | } | |
440 | ||
441 | static unsigned int pack_used_ctr; | |
442 | static unsigned int pack_mmap_calls; | |
443 | static unsigned int peak_pack_open_windows; | |
444 | static unsigned int pack_open_windows; | |
445 | static unsigned int pack_open_fds; | |
446 | static unsigned int pack_max_fds; | |
447 | static size_t peak_pack_mapped; | |
448 | static size_t pack_mapped; | |
449 | struct packed_git *packed_git; | |
450 | ||
451 | void pack_report(void) | |
452 | { | |
453 | fprintf(stderr, | |
454 | "pack_report: getpagesize() = %10" SZ_FMT "\n" | |
455 | "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n" | |
456 | "pack_report: core.packedGitLimit = %10" SZ_FMT "\n", | |
457 | sz_fmt(getpagesize()), | |
458 | sz_fmt(packed_git_window_size), | |
459 | sz_fmt(packed_git_limit)); | |
460 | fprintf(stderr, | |
461 | "pack_report: pack_used_ctr = %10u\n" | |
462 | "pack_report: pack_mmap_calls = %10u\n" | |
463 | "pack_report: pack_open_windows = %10u / %10u\n" | |
464 | "pack_report: pack_mapped = " | |
465 | "%10" SZ_FMT " / %10" SZ_FMT "\n", | |
466 | pack_used_ctr, | |
467 | pack_mmap_calls, | |
468 | pack_open_windows, peak_pack_open_windows, | |
469 | sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped)); | |
470 | } | |
471 | ||
472 | static int check_packed_git_idx(const char *path, struct packed_git *p) | |
473 | { | |
474 | void *idx_map; | |
475 | struct pack_idx_header *hdr; | |
476 | size_t idx_size; | |
477 | uint32_t version, nr, i, *index; | |
478 | int fd = git_open_noatime(path); | |
479 | struct stat st; | |
480 | ||
481 | if (fd < 0) | |
482 | return -1; | |
483 | if (fstat(fd, &st)) { | |
484 | close(fd); | |
485 | return -1; | |
486 | } | |
487 | idx_size = xsize_t(st.st_size); | |
488 | if (idx_size < 4 * 256 + 20 + 20) { | |
489 | close(fd); | |
490 | return error("index file %s is too small", path); | |
491 | } | |
492 | idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0); | |
493 | close(fd); | |
494 | ||
495 | hdr = idx_map; | |
496 | if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) { | |
497 | version = ntohl(hdr->idx_version); | |
498 | if (version < 2 || version > 2) { | |
499 | munmap(idx_map, idx_size); | |
500 | return error("index file %s is version %"PRIu32 | |
501 | " and is not supported by this binary" | |
502 | " (try upgrading GIT to a newer version)", | |
503 | path, version); | |
504 | } | |
505 | } else | |
506 | version = 1; | |
507 | ||
508 | nr = 0; | |
509 | index = idx_map; | |
510 | if (version > 1) | |
511 | index += 2; /* skip index header */ | |
512 | for (i = 0; i < 256; i++) { | |
513 | uint32_t n = ntohl(index[i]); | |
514 | if (n < nr) { | |
515 | munmap(idx_map, idx_size); | |
516 | return error("non-monotonic index %s", path); | |
517 | } | |
518 | nr = n; | |
519 | } | |
520 | ||
521 | if (version == 1) { | |
522 | /* | |
523 | * Total size: | |
524 | * - 256 index entries 4 bytes each | |
525 | * - 24-byte entries * nr (20-byte sha1 + 4-byte offset) | |
526 | * - 20-byte SHA1 of the packfile | |
527 | * - 20-byte SHA1 file checksum | |
528 | */ | |
529 | if (idx_size != 4*256 + nr * 24 + 20 + 20) { | |
530 | munmap(idx_map, idx_size); | |
531 | return error("wrong index v1 file size in %s", path); | |
532 | } | |
533 | } else if (version == 2) { | |
534 | /* | |
535 | * Minimum size: | |
536 | * - 8 bytes of header | |
537 | * - 256 index entries 4 bytes each | |
538 | * - 20-byte sha1 entry * nr | |
539 | * - 4-byte crc entry * nr | |
540 | * - 4-byte offset entry * nr | |
541 | * - 20-byte SHA1 of the packfile | |
542 | * - 20-byte SHA1 file checksum | |
543 | * And after the 4-byte offset table might be a | |
544 | * variable sized table containing 8-byte entries | |
545 | * for offsets larger than 2^31. | |
546 | */ | |
547 | unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20; | |
548 | unsigned long max_size = min_size; | |
549 | if (nr) | |
550 | max_size += (nr - 1)*8; | |
551 | if (idx_size < min_size || idx_size > max_size) { | |
552 | munmap(idx_map, idx_size); | |
553 | return error("wrong index v2 file size in %s", path); | |
554 | } | |
555 | if (idx_size != min_size && | |
556 | /* | |
557 | * make sure we can deal with large pack offsets. | |
558 | * 31-bit signed offset won't be enough, neither | |
559 | * 32-bit unsigned one will be. | |
560 | */ | |
561 | (sizeof(off_t) <= 4)) { | |
562 | munmap(idx_map, idx_size); | |
563 | return error("pack too large for current definition of off_t in %s", path); | |
564 | } | |
565 | } | |
566 | ||
567 | p->index_version = version; | |
568 | p->index_data = idx_map; | |
569 | p->index_size = idx_size; | |
570 | p->num_objects = nr; | |
571 | return 0; | |
572 | } | |
573 | ||
574 | int open_pack_index(struct packed_git *p) | |
575 | { | |
576 | char *idx_name; | |
577 | int ret; | |
578 | ||
579 | if (p->index_data) | |
580 | return 0; | |
581 | ||
582 | idx_name = xstrdup(p->pack_name); | |
583 | strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx"); | |
584 | ret = check_packed_git_idx(idx_name, p); | |
585 | free(idx_name); | |
586 | return ret; | |
587 | } | |
588 | ||
589 | static void scan_windows(struct packed_git *p, | |
590 | struct packed_git **lru_p, | |
591 | struct pack_window **lru_w, | |
592 | struct pack_window **lru_l) | |
593 | { | |
594 | struct pack_window *w, *w_l; | |
595 | ||
596 | for (w_l = NULL, w = p->windows; w; w = w->next) { | |
597 | if (!w->inuse_cnt) { | |
598 | if (!*lru_w || w->last_used < (*lru_w)->last_used) { | |
599 | *lru_p = p; | |
600 | *lru_w = w; | |
601 | *lru_l = w_l; | |
602 | } | |
603 | } | |
604 | w_l = w; | |
605 | } | |
606 | } | |
607 | ||
608 | static int unuse_one_window(struct packed_git *current, int keep_fd) | |
609 | { | |
610 | struct packed_git *p, *lru_p = NULL; | |
611 | struct pack_window *lru_w = NULL, *lru_l = NULL; | |
612 | ||
613 | if (current) | |
614 | scan_windows(current, &lru_p, &lru_w, &lru_l); | |
615 | for (p = packed_git; p; p = p->next) | |
616 | scan_windows(p, &lru_p, &lru_w, &lru_l); | |
617 | if (lru_p) { | |
618 | munmap(lru_w->base, lru_w->len); | |
619 | pack_mapped -= lru_w->len; | |
620 | if (lru_l) | |
621 | lru_l->next = lru_w->next; | |
622 | else { | |
623 | lru_p->windows = lru_w->next; | |
624 | if (!lru_p->windows && lru_p->pack_fd != -1 | |
625 | && lru_p->pack_fd != keep_fd) { | |
626 | close(lru_p->pack_fd); | |
627 | pack_open_fds--; | |
628 | lru_p->pack_fd = -1; | |
629 | } | |
630 | } | |
631 | free(lru_w); | |
632 | pack_open_windows--; | |
633 | return 1; | |
634 | } | |
635 | return 0; | |
636 | } | |
637 | ||
638 | void release_pack_memory(size_t need, int fd) | |
639 | { | |
640 | size_t cur = pack_mapped; | |
641 | while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd)) | |
642 | ; /* nothing */ | |
643 | } | |
644 | ||
645 | void *xmmap(void *start, size_t length, | |
646 | int prot, int flags, int fd, off_t offset) | |
647 | { | |
648 | void *ret = mmap(start, length, prot, flags, fd, offset); | |
649 | if (ret == MAP_FAILED) { | |
650 | if (!length) | |
651 | return NULL; | |
652 | release_pack_memory(length, fd); | |
653 | ret = mmap(start, length, prot, flags, fd, offset); | |
654 | if (ret == MAP_FAILED) | |
655 | die_errno("Out of memory? mmap failed"); | |
656 | } | |
657 | return ret; | |
658 | } | |
659 | ||
660 | void close_pack_windows(struct packed_git *p) | |
661 | { | |
662 | while (p->windows) { | |
663 | struct pack_window *w = p->windows; | |
664 | ||
665 | if (w->inuse_cnt) | |
666 | die("pack '%s' still has open windows to it", | |
667 | p->pack_name); | |
668 | munmap(w->base, w->len); | |
669 | pack_mapped -= w->len; | |
670 | pack_open_windows--; | |
671 | p->windows = w->next; | |
672 | free(w); | |
673 | } | |
674 | } | |
675 | ||
676 | void unuse_pack(struct pack_window **w_cursor) | |
677 | { | |
678 | struct pack_window *w = *w_cursor; | |
679 | if (w) { | |
680 | w->inuse_cnt--; | |
681 | *w_cursor = NULL; | |
682 | } | |
683 | } | |
684 | ||
685 | void close_pack_index(struct packed_git *p) | |
686 | { | |
687 | if (p->index_data) { | |
688 | munmap((void *)p->index_data, p->index_size); | |
689 | p->index_data = NULL; | |
690 | } | |
691 | } | |
692 | ||
693 | /* | |
694 | * This is used by git-repack in case a newly created pack happens to | |
695 | * contain the same set of objects as an existing one. In that case | |
696 | * the resulting file might be different even if its name would be the | |
697 | * same. It is best to close any reference to the old pack before it is | |
698 | * replaced on disk. Of course no index pointers nor windows for given pack | |
699 | * must subsist at this point. If ever objects from this pack are requested | |
700 | * again, the new version of the pack will be reinitialized through | |
701 | * reprepare_packed_git(). | |
702 | */ | |
703 | void free_pack_by_name(const char *pack_name) | |
704 | { | |
705 | struct packed_git *p, **pp = &packed_git; | |
706 | ||
707 | while (*pp) { | |
708 | p = *pp; | |
709 | if (strcmp(pack_name, p->pack_name) == 0) { | |
710 | clear_delta_base_cache(); | |
711 | close_pack_windows(p); | |
712 | if (p->pack_fd != -1) { | |
713 | close(p->pack_fd); | |
714 | pack_open_fds--; | |
715 | } | |
716 | close_pack_index(p); | |
717 | free(p->bad_object_sha1); | |
718 | *pp = p->next; | |
719 | free(p); | |
720 | return; | |
721 | } | |
722 | pp = &p->next; | |
723 | } | |
724 | } | |
725 | ||
726 | /* | |
727 | * Do not call this directly as this leaks p->pack_fd on error return; | |
728 | * call open_packed_git() instead. | |
729 | */ | |
730 | static int open_packed_git_1(struct packed_git *p) | |
731 | { | |
732 | struct stat st; | |
733 | struct pack_header hdr; | |
734 | unsigned char sha1[20]; | |
735 | unsigned char *idx_sha1; | |
736 | long fd_flag; | |
737 | ||
738 | if (!p->index_data && open_pack_index(p)) | |
739 | return error("packfile %s index unavailable", p->pack_name); | |
740 | ||
741 | if (!pack_max_fds) { | |
742 | struct rlimit lim; | |
743 | unsigned int max_fds; | |
744 | ||
745 | if (getrlimit(RLIMIT_NOFILE, &lim)) | |
746 | die_errno("cannot get RLIMIT_NOFILE"); | |
747 | ||
748 | max_fds = lim.rlim_cur; | |
749 | ||
750 | /* Save 3 for stdin/stdout/stderr, 22 for work */ | |
751 | if (25 < max_fds) | |
752 | pack_max_fds = max_fds - 25; | |
753 | else | |
754 | pack_max_fds = 1; | |
755 | } | |
756 | ||
757 | while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1)) | |
758 | ; /* nothing */ | |
759 | ||
760 | p->pack_fd = git_open_noatime(p->pack_name); | |
761 | if (p->pack_fd < 0 || fstat(p->pack_fd, &st)) | |
762 | return -1; | |
763 | pack_open_fds++; | |
764 | ||
765 | /* If we created the struct before we had the pack we lack size. */ | |
766 | if (!p->pack_size) { | |
767 | if (!S_ISREG(st.st_mode)) | |
768 | return error("packfile %s not a regular file", p->pack_name); | |
769 | p->pack_size = st.st_size; | |
770 | } else if (p->pack_size != st.st_size) | |
771 | return error("packfile %s size changed", p->pack_name); | |
772 | ||
773 | /* We leave these file descriptors open with sliding mmap; | |
774 | * there is no point keeping them open across exec(), though. | |
775 | */ | |
776 | fd_flag = fcntl(p->pack_fd, F_GETFD, 0); | |
777 | if (fd_flag < 0) | |
778 | return error("cannot determine file descriptor flags"); | |
779 | fd_flag |= FD_CLOEXEC; | |
780 | if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1) | |
781 | return error("cannot set FD_CLOEXEC"); | |
782 | ||
783 | /* Verify we recognize this pack file format. */ | |
784 | if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr)) | |
785 | return error("file %s is far too short to be a packfile", p->pack_name); | |
786 | if (hdr.hdr_signature != htonl(PACK_SIGNATURE)) | |
787 | return error("file %s is not a GIT packfile", p->pack_name); | |
788 | if (!pack_version_ok(hdr.hdr_version)) | |
789 | return error("packfile %s is version %"PRIu32" and not" | |
790 | " supported (try upgrading GIT to a newer version)", | |
791 | p->pack_name, ntohl(hdr.hdr_version)); | |
792 | ||
793 | /* Verify the pack matches its index. */ | |
794 | if (p->num_objects != ntohl(hdr.hdr_entries)) | |
795 | return error("packfile %s claims to have %"PRIu32" objects" | |
796 | " while index indicates %"PRIu32" objects", | |
797 | p->pack_name, ntohl(hdr.hdr_entries), | |
798 | p->num_objects); | |
799 | if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1) | |
800 | return error("end of packfile %s is unavailable", p->pack_name); | |
801 | if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1)) | |
802 | return error("packfile %s signature is unavailable", p->pack_name); | |
803 | idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40; | |
804 | if (hashcmp(sha1, idx_sha1)) | |
805 | return error("packfile %s does not match index", p->pack_name); | |
806 | return 0; | |
807 | } | |
808 | ||
809 | static int open_packed_git(struct packed_git *p) | |
810 | { | |
811 | if (!open_packed_git_1(p)) | |
812 | return 0; | |
813 | if (p->pack_fd != -1) { | |
814 | close(p->pack_fd); | |
815 | pack_open_fds--; | |
816 | p->pack_fd = -1; | |
817 | } | |
818 | return -1; | |
819 | } | |
820 | ||
821 | static int in_window(struct pack_window *win, off_t offset) | |
822 | { | |
823 | /* We must promise at least 20 bytes (one hash) after the | |
824 | * offset is available from this window, otherwise the offset | |
825 | * is not actually in this window and a different window (which | |
826 | * has that one hash excess) must be used. This is to support | |
827 | * the object header and delta base parsing routines below. | |
828 | */ | |
829 | off_t win_off = win->offset; | |
830 | return win_off <= offset | |
831 | && (offset + 20) <= (win_off + win->len); | |
832 | } | |
833 | ||
834 | unsigned char *use_pack(struct packed_git *p, | |
835 | struct pack_window **w_cursor, | |
836 | off_t offset, | |
837 | unsigned int *left) | |
838 | { | |
839 | struct pack_window *win = *w_cursor; | |
840 | ||
841 | /* Since packfiles end in a hash of their content and it's | |
842 | * pointless to ask for an offset into the middle of that | |
843 | * hash, and the in_window function above wouldn't match | |
844 | * don't allow an offset too close to the end of the file. | |
845 | */ | |
846 | if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p)) | |
847 | die("packfile %s cannot be accessed", p->pack_name); | |
848 | if (offset > (p->pack_size - 20)) | |
849 | die("offset beyond end of packfile (truncated pack?)"); | |
850 | ||
851 | if (!win || !in_window(win, offset)) { | |
852 | if (win) | |
853 | win->inuse_cnt--; | |
854 | for (win = p->windows; win; win = win->next) { | |
855 | if (in_window(win, offset)) | |
856 | break; | |
857 | } | |
858 | if (!win) { | |
859 | size_t window_align = packed_git_window_size / 2; | |
860 | off_t len; | |
861 | ||
862 | if (p->pack_fd == -1 && open_packed_git(p)) | |
863 | die("packfile %s cannot be accessed", p->pack_name); | |
864 | ||
865 | win = xcalloc(1, sizeof(*win)); | |
866 | win->offset = (offset / window_align) * window_align; | |
867 | len = p->pack_size - win->offset; | |
868 | if (len > packed_git_window_size) | |
869 | len = packed_git_window_size; | |
870 | win->len = (size_t)len; | |
871 | pack_mapped += win->len; | |
872 | while (packed_git_limit < pack_mapped | |
873 | && unuse_one_window(p, p->pack_fd)) | |
874 | ; /* nothing */ | |
875 | win->base = xmmap(NULL, win->len, | |
876 | PROT_READ, MAP_PRIVATE, | |
877 | p->pack_fd, win->offset); | |
878 | if (win->base == MAP_FAILED) | |
879 | die("packfile %s cannot be mapped: %s", | |
880 | p->pack_name, | |
881 | strerror(errno)); | |
882 | if (!win->offset && win->len == p->pack_size | |
883 | && !p->do_not_close) { | |
884 | close(p->pack_fd); | |
885 | pack_open_fds--; | |
886 | p->pack_fd = -1; | |
887 | } | |
888 | pack_mmap_calls++; | |
889 | pack_open_windows++; | |
890 | if (pack_mapped > peak_pack_mapped) | |
891 | peak_pack_mapped = pack_mapped; | |
892 | if (pack_open_windows > peak_pack_open_windows) | |
893 | peak_pack_open_windows = pack_open_windows; | |
894 | win->next = p->windows; | |
895 | p->windows = win; | |
896 | } | |
897 | } | |
898 | if (win != *w_cursor) { | |
899 | win->last_used = pack_used_ctr++; | |
900 | win->inuse_cnt++; | |
901 | *w_cursor = win; | |
902 | } | |
903 | offset -= win->offset; | |
904 | if (left) | |
905 | *left = win->len - xsize_t(offset); | |
906 | return win->base + offset; | |
907 | } | |
908 | ||
909 | static struct packed_git *alloc_packed_git(int extra) | |
910 | { | |
911 | struct packed_git *p = xmalloc(sizeof(*p) + extra); | |
912 | memset(p, 0, sizeof(*p)); | |
913 | p->pack_fd = -1; | |
914 | return p; | |
915 | } | |
916 | ||
917 | static void try_to_free_pack_memory(size_t size) | |
918 | { | |
919 | release_pack_memory(size, -1); | |
920 | } | |
921 | ||
922 | struct packed_git *add_packed_git(const char *path, int path_len, int local) | |
923 | { | |
924 | static int have_set_try_to_free_routine; | |
925 | struct stat st; | |
926 | struct packed_git *p = alloc_packed_git(path_len + 2); | |
927 | ||
928 | if (!have_set_try_to_free_routine) { | |
929 | have_set_try_to_free_routine = 1; | |
930 | set_try_to_free_routine(try_to_free_pack_memory); | |
931 | } | |
932 | ||
933 | /* | |
934 | * Make sure a corresponding .pack file exists and that | |
935 | * the index looks sane. | |
936 | */ | |
937 | path_len -= strlen(".idx"); | |
938 | if (path_len < 1) { | |
939 | free(p); | |
940 | return NULL; | |
941 | } | |
942 | memcpy(p->pack_name, path, path_len); | |
943 | ||
944 | strcpy(p->pack_name + path_len, ".keep"); | |
945 | if (!access(p->pack_name, F_OK)) | |
946 | p->pack_keep = 1; | |
947 | ||
948 | strcpy(p->pack_name + path_len, ".pack"); | |
949 | if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) { | |
950 | free(p); | |
951 | return NULL; | |
952 | } | |
953 | ||
954 | /* ok, it looks sane as far as we can check without | |
955 | * actually mapping the pack file. | |
956 | */ | |
957 | p->pack_size = st.st_size; | |
958 | p->pack_local = local; | |
959 | p->mtime = st.st_mtime; | |
960 | if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1)) | |
961 | hashclr(p->sha1); | |
962 | return p; | |
963 | } | |
964 | ||
965 | struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path) | |
966 | { | |
967 | const char *path = sha1_pack_name(sha1); | |
968 | struct packed_git *p = alloc_packed_git(strlen(path) + 1); | |
969 | ||
970 | strcpy(p->pack_name, path); | |
971 | hashcpy(p->sha1, sha1); | |
972 | if (check_packed_git_idx(idx_path, p)) { | |
973 | free(p); | |
974 | return NULL; | |
975 | } | |
976 | ||
977 | return p; | |
978 | } | |
979 | ||
980 | void install_packed_git(struct packed_git *pack) | |
981 | { | |
982 | if (pack->pack_fd != -1) | |
983 | pack_open_fds++; | |
984 | ||
985 | pack->next = packed_git; | |
986 | packed_git = pack; | |
987 | } | |
988 | ||
989 | static void prepare_packed_git_one(char *objdir, int local) | |
990 | { | |
991 | /* Ensure that this buffer is large enough so that we can | |
992 | append "/pack/" without clobbering the stack even if | |
993 | strlen(objdir) were PATH_MAX. */ | |
994 | char path[PATH_MAX + 1 + 4 + 1 + 1]; | |
995 | int len; | |
996 | DIR *dir; | |
997 | struct dirent *de; | |
998 | ||
999 | sprintf(path, "%s/pack", objdir); | |
1000 | len = strlen(path); | |
1001 | dir = opendir(path); | |
1002 | if (!dir) { | |
1003 | if (errno != ENOENT) | |
1004 | error("unable to open object pack directory: %s: %s", | |
1005 | path, strerror(errno)); | |
1006 | return; | |
1007 | } | |
1008 | path[len++] = '/'; | |
1009 | while ((de = readdir(dir)) != NULL) { | |
1010 | int namelen = strlen(de->d_name); | |
1011 | struct packed_git *p; | |
1012 | ||
1013 | if (!has_extension(de->d_name, ".idx")) | |
1014 | continue; | |
1015 | ||
1016 | if (len + namelen + 1 > sizeof(path)) | |
1017 | continue; | |
1018 | ||
1019 | /* Don't reopen a pack we already have. */ | |
1020 | strcpy(path + len, de->d_name); | |
1021 | for (p = packed_git; p; p = p->next) { | |
1022 | if (!memcmp(path, p->pack_name, len + namelen - 4)) | |
1023 | break; | |
1024 | } | |
1025 | if (p) | |
1026 | continue; | |
1027 | /* See if it really is a valid .idx file with corresponding | |
1028 | * .pack file that we can map. | |
1029 | */ | |
1030 | p = add_packed_git(path, len + namelen, local); | |
1031 | if (!p) | |
1032 | continue; | |
1033 | install_packed_git(p); | |
1034 | } | |
1035 | closedir(dir); | |
1036 | } | |
1037 | ||
1038 | static int sort_pack(const void *a_, const void *b_) | |
1039 | { | |
1040 | struct packed_git *a = *((struct packed_git **)a_); | |
1041 | struct packed_git *b = *((struct packed_git **)b_); | |
1042 | int st; | |
1043 | ||
1044 | /* | |
1045 | * Local packs tend to contain objects specific to our | |
1046 | * variant of the project than remote ones. In addition, | |
1047 | * remote ones could be on a network mounted filesystem. | |
1048 | * Favor local ones for these reasons. | |
1049 | */ | |
1050 | st = a->pack_local - b->pack_local; | |
1051 | if (st) | |
1052 | return -st; | |
1053 | ||
1054 | /* | |
1055 | * Younger packs tend to contain more recent objects, | |
1056 | * and more recent objects tend to get accessed more | |
1057 | * often. | |
1058 | */ | |
1059 | if (a->mtime < b->mtime) | |
1060 | return 1; | |
1061 | else if (a->mtime == b->mtime) | |
1062 | return 0; | |
1063 | return -1; | |
1064 | } | |
1065 | ||
1066 | static void rearrange_packed_git(void) | |
1067 | { | |
1068 | struct packed_git **ary, *p; | |
1069 | int i, n; | |
1070 | ||
1071 | for (n = 0, p = packed_git; p; p = p->next) | |
1072 | n++; | |
1073 | if (n < 2) | |
1074 | return; | |
1075 | ||
1076 | /* prepare an array of packed_git for easier sorting */ | |
1077 | ary = xcalloc(n, sizeof(struct packed_git *)); | |
1078 | for (n = 0, p = packed_git; p; p = p->next) | |
1079 | ary[n++] = p; | |
1080 | ||
1081 | qsort(ary, n, sizeof(struct packed_git *), sort_pack); | |
1082 | ||
1083 | /* link them back again */ | |
1084 | for (i = 0; i < n - 1; i++) | |
1085 | ary[i]->next = ary[i + 1]; | |
1086 | ary[n - 1]->next = NULL; | |
1087 | packed_git = ary[0]; | |
1088 | ||
1089 | free(ary); | |
1090 | } | |
1091 | ||
1092 | static int prepare_packed_git_run_once = 0; | |
1093 | void prepare_packed_git(void) | |
1094 | { | |
1095 | struct alternate_object_database *alt; | |
1096 | ||
1097 | if (prepare_packed_git_run_once) | |
1098 | return; | |
1099 | prepare_packed_git_one(get_object_directory(), 1); | |
1100 | prepare_alt_odb(); | |
1101 | for (alt = alt_odb_list; alt; alt = alt->next) { | |
1102 | alt->name[-1] = 0; | |
1103 | prepare_packed_git_one(alt->base, 0); | |
1104 | alt->name[-1] = '/'; | |
1105 | } | |
1106 | rearrange_packed_git(); | |
1107 | prepare_packed_git_run_once = 1; | |
1108 | } | |
1109 | ||
1110 | void reprepare_packed_git(void) | |
1111 | { | |
1112 | discard_revindex(); | |
1113 | prepare_packed_git_run_once = 0; | |
1114 | prepare_packed_git(); | |
1115 | } | |
1116 | ||
1117 | static void mark_bad_packed_object(struct packed_git *p, | |
1118 | const unsigned char *sha1) | |
1119 | { | |
1120 | unsigned i; | |
1121 | for (i = 0; i < p->num_bad_objects; i++) | |
1122 | if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) | |
1123 | return; | |
1124 | p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1)); | |
1125 | hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1); | |
1126 | p->num_bad_objects++; | |
1127 | } | |
1128 | ||
1129 | static const struct packed_git *has_packed_and_bad(const unsigned char *sha1) | |
1130 | { | |
1131 | struct packed_git *p; | |
1132 | unsigned i; | |
1133 | ||
1134 | for (p = packed_git; p; p = p->next) | |
1135 | for (i = 0; i < p->num_bad_objects; i++) | |
1136 | if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) | |
1137 | return p; | |
1138 | return NULL; | |
1139 | } | |
1140 | ||
1141 | int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type) | |
1142 | { | |
1143 | unsigned char real_sha1[20]; | |
1144 | hash_sha1_file(map, size, type, real_sha1); | |
1145 | return hashcmp(sha1, real_sha1) ? -1 : 0; | |
1146 | } | |
1147 | ||
1148 | static int git_open_noatime(const char *name) | |
1149 | { | |
1150 | static int sha1_file_open_flag = O_NOATIME; | |
1151 | ||
1152 | for (;;) { | |
1153 | int fd = open(name, O_RDONLY | sha1_file_open_flag); | |
1154 | if (fd >= 0) | |
1155 | return fd; | |
1156 | ||
1157 | /* Might the failure be due to O_NOATIME? */ | |
1158 | if (errno != ENOENT && sha1_file_open_flag) { | |
1159 | sha1_file_open_flag = 0; | |
1160 | continue; | |
1161 | } | |
1162 | ||
1163 | return -1; | |
1164 | } | |
1165 | } | |
1166 | ||
1167 | static int open_sha1_file(const unsigned char *sha1) | |
1168 | { | |
1169 | int fd; | |
1170 | char *name = sha1_file_name(sha1); | |
1171 | struct alternate_object_database *alt; | |
1172 | ||
1173 | fd = git_open_noatime(name); | |
1174 | if (fd >= 0) | |
1175 | return fd; | |
1176 | ||
1177 | prepare_alt_odb(); | |
1178 | errno = ENOENT; | |
1179 | for (alt = alt_odb_list; alt; alt = alt->next) { | |
1180 | name = alt->name; | |
1181 | fill_sha1_path(name, sha1); | |
1182 | fd = git_open_noatime(alt->base); | |
1183 | if (fd >= 0) | |
1184 | return fd; | |
1185 | } | |
1186 | return -1; | |
1187 | } | |
1188 | ||
1189 | static void *map_sha1_file(const unsigned char *sha1, unsigned long *size) | |
1190 | { | |
1191 | void *map; | |
1192 | int fd; | |
1193 | ||
1194 | fd = open_sha1_file(sha1); | |
1195 | map = NULL; | |
1196 | if (fd >= 0) { | |
1197 | struct stat st; | |
1198 | ||
1199 | if (!fstat(fd, &st)) { | |
1200 | *size = xsize_t(st.st_size); | |
1201 | map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0); | |
1202 | } | |
1203 | close(fd); | |
1204 | } | |
1205 | return map; | |
1206 | } | |
1207 | ||
1208 | static int legacy_loose_object(unsigned char *map) | |
1209 | { | |
1210 | unsigned int word; | |
1211 | ||
1212 | /* | |
1213 | * Is it a zlib-compressed buffer? If so, the first byte | |
1214 | * must be 0x78 (15-bit window size, deflated), and the | |
1215 | * first 16-bit word is evenly divisible by 31 | |
1216 | */ | |
1217 | word = (map[0] << 8) + map[1]; | |
1218 | if (map[0] == 0x78 && !(word % 31)) | |
1219 | return 1; | |
1220 | else | |
1221 | return 0; | |
1222 | } | |
1223 | ||
1224 | unsigned long unpack_object_header_buffer(const unsigned char *buf, | |
1225 | unsigned long len, enum object_type *type, unsigned long *sizep) | |
1226 | { | |
1227 | unsigned shift; | |
1228 | unsigned long size, c; | |
1229 | unsigned long used = 0; | |
1230 | ||
1231 | c = buf[used++]; | |
1232 | *type = (c >> 4) & 7; | |
1233 | size = c & 15; | |
1234 | shift = 4; | |
1235 | while (c & 0x80) { | |
1236 | if (len <= used || bitsizeof(long) <= shift) { | |
1237 | error("bad object header"); | |
1238 | return 0; | |
1239 | } | |
1240 | c = buf[used++]; | |
1241 | size += (c & 0x7f) << shift; | |
1242 | shift += 7; | |
1243 | } | |
1244 | *sizep = size; | |
1245 | return used; | |
1246 | } | |
1247 | ||
1248 | static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz) | |
1249 | { | |
1250 | unsigned long size, used; | |
1251 | static const char valid_loose_object_type[8] = { | |
1252 | 0, /* OBJ_EXT */ | |
1253 | 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */ | |
1254 | 0, /* "delta" and others are invalid in a loose object */ | |
1255 | }; | |
1256 | enum object_type type; | |
1257 | ||
1258 | /* Get the data stream */ | |
1259 | memset(stream, 0, sizeof(*stream)); | |
1260 | stream->next_in = map; | |
1261 | stream->avail_in = mapsize; | |
1262 | stream->next_out = buffer; | |
1263 | stream->avail_out = bufsiz; | |
1264 | ||
1265 | if (legacy_loose_object(map)) { | |
1266 | git_inflate_init(stream); | |
1267 | return git_inflate(stream, 0); | |
1268 | } | |
1269 | ||
1270 | ||
1271 | /* | |
1272 | * There used to be a second loose object header format which | |
1273 | * was meant to mimic the in-pack format, allowing for direct | |
1274 | * copy of the object data. This format turned up not to be | |
1275 | * really worth it and we don't write it any longer. But we | |
1276 | * can still read it. | |
1277 | */ | |
1278 | used = unpack_object_header_buffer(map, mapsize, &type, &size); | |
1279 | if (!used || !valid_loose_object_type[type]) | |
1280 | return -1; | |
1281 | map += used; | |
1282 | mapsize -= used; | |
1283 | ||
1284 | /* Set up the stream for the rest.. */ | |
1285 | stream->next_in = map; | |
1286 | stream->avail_in = mapsize; | |
1287 | git_inflate_init(stream); | |
1288 | ||
1289 | /* And generate the fake traditional header */ | |
1290 | stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu", | |
1291 | typename(type), size); | |
1292 | return 0; | |
1293 | } | |
1294 | ||
1295 | static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size, const unsigned char *sha1) | |
1296 | { | |
1297 | int bytes = strlen(buffer) + 1; | |
1298 | unsigned char *buf = xmallocz(size); | |
1299 | unsigned long n; | |
1300 | int status = Z_OK; | |
1301 | ||
1302 | n = stream->total_out - bytes; | |
1303 | if (n > size) | |
1304 | n = size; | |
1305 | memcpy(buf, (char *) buffer + bytes, n); | |
1306 | bytes = n; | |
1307 | if (bytes <= size) { | |
1308 | /* | |
1309 | * The above condition must be (bytes <= size), not | |
1310 | * (bytes < size). In other words, even though we | |
1311 | * expect no more output and set avail_out to zero, | |
1312 | * the input zlib stream may have bytes that express | |
1313 | * "this concludes the stream", and we *do* want to | |
1314 | * eat that input. | |
1315 | * | |
1316 | * Otherwise we would not be able to test that we | |
1317 | * consumed all the input to reach the expected size; | |
1318 | * we also want to check that zlib tells us that all | |
1319 | * went well with status == Z_STREAM_END at the end. | |
1320 | */ | |
1321 | stream->next_out = buf + bytes; | |
1322 | stream->avail_out = size - bytes; | |
1323 | while (status == Z_OK) | |
1324 | status = git_inflate(stream, Z_FINISH); | |
1325 | } | |
1326 | if (status == Z_STREAM_END && !stream->avail_in) { | |
1327 | git_inflate_end(stream); | |
1328 | return buf; | |
1329 | } | |
1330 | ||
1331 | if (status < 0) | |
1332 | error("corrupt loose object '%s'", sha1_to_hex(sha1)); | |
1333 | else if (stream->avail_in) | |
1334 | error("garbage at end of loose object '%s'", | |
1335 | sha1_to_hex(sha1)); | |
1336 | free(buf); | |
1337 | return NULL; | |
1338 | } | |
1339 | ||
1340 | /* | |
1341 | * We used to just use "sscanf()", but that's actually way | |
1342 | * too permissive for what we want to check. So do an anal | |
1343 | * object header parse by hand. | |
1344 | */ | |
1345 | static int parse_sha1_header(const char *hdr, unsigned long *sizep) | |
1346 | { | |
1347 | char type[10]; | |
1348 | int i; | |
1349 | unsigned long size; | |
1350 | ||
1351 | /* | |
1352 | * The type can be at most ten bytes (including the | |
1353 | * terminating '\0' that we add), and is followed by | |
1354 | * a space. | |
1355 | */ | |
1356 | i = 0; | |
1357 | for (;;) { | |
1358 | char c = *hdr++; | |
1359 | if (c == ' ') | |
1360 | break; | |
1361 | type[i++] = c; | |
1362 | if (i >= sizeof(type)) | |
1363 | return -1; | |
1364 | } | |
1365 | type[i] = 0; | |
1366 | ||
1367 | /* | |
1368 | * The length must follow immediately, and be in canonical | |
1369 | * decimal format (ie "010" is not valid). | |
1370 | */ | |
1371 | size = *hdr++ - '0'; | |
1372 | if (size > 9) | |
1373 | return -1; | |
1374 | if (size) { | |
1375 | for (;;) { | |
1376 | unsigned long c = *hdr - '0'; | |
1377 | if (c > 9) | |
1378 | break; | |
1379 | hdr++; | |
1380 | size = size * 10 + c; | |
1381 | } | |
1382 | } | |
1383 | *sizep = size; | |
1384 | ||
1385 | /* | |
1386 | * The length must be followed by a zero byte | |
1387 | */ | |
1388 | return *hdr ? -1 : type_from_string(type); | |
1389 | } | |
1390 | ||
1391 | static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1) | |
1392 | { | |
1393 | int ret; | |
1394 | z_stream stream; | |
1395 | char hdr[8192]; | |
1396 | ||
1397 | ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)); | |
1398 | if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0) | |
1399 | return NULL; | |
1400 | ||
1401 | return unpack_sha1_rest(&stream, hdr, *size, sha1); | |
1402 | } | |
1403 | ||
1404 | unsigned long get_size_from_delta(struct packed_git *p, | |
1405 | struct pack_window **w_curs, | |
1406 | off_t curpos) | |
1407 | { | |
1408 | const unsigned char *data; | |
1409 | unsigned char delta_head[20], *in; | |
1410 | z_stream stream; | |
1411 | int st; | |
1412 | ||
1413 | memset(&stream, 0, sizeof(stream)); | |
1414 | stream.next_out = delta_head; | |
1415 | stream.avail_out = sizeof(delta_head); | |
1416 | ||
1417 | git_inflate_init(&stream); | |
1418 | do { | |
1419 | in = use_pack(p, w_curs, curpos, &stream.avail_in); | |
1420 | stream.next_in = in; | |
1421 | st = git_inflate(&stream, Z_FINISH); | |
1422 | curpos += stream.next_in - in; | |
1423 | } while ((st == Z_OK || st == Z_BUF_ERROR) && | |
1424 | stream.total_out < sizeof(delta_head)); | |
1425 | git_inflate_end(&stream); | |
1426 | if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) { | |
1427 | error("delta data unpack-initial failed"); | |
1428 | return 0; | |
1429 | } | |
1430 | ||
1431 | /* Examine the initial part of the delta to figure out | |
1432 | * the result size. | |
1433 | */ | |
1434 | data = delta_head; | |
1435 | ||
1436 | /* ignore base size */ | |
1437 | get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); | |
1438 | ||
1439 | /* Read the result size */ | |
1440 | return get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); | |
1441 | } | |
1442 | ||
1443 | static off_t get_delta_base(struct packed_git *p, | |
1444 | struct pack_window **w_curs, | |
1445 | off_t *curpos, | |
1446 | enum object_type type, | |
1447 | off_t delta_obj_offset) | |
1448 | { | |
1449 | unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL); | |
1450 | off_t base_offset; | |
1451 | ||
1452 | /* use_pack() assured us we have [base_info, base_info + 20) | |
1453 | * as a range that we can look at without walking off the | |
1454 | * end of the mapped window. Its actually the hash size | |
1455 | * that is assured. An OFS_DELTA longer than the hash size | |
1456 | * is stupid, as then a REF_DELTA would be smaller to store. | |
1457 | */ | |
1458 | if (type == OBJ_OFS_DELTA) { | |
1459 | unsigned used = 0; | |
1460 | unsigned char c = base_info[used++]; | |
1461 | base_offset = c & 127; | |
1462 | while (c & 128) { | |
1463 | base_offset += 1; | |
1464 | if (!base_offset || MSB(base_offset, 7)) | |
1465 | return 0; /* overflow */ | |
1466 | c = base_info[used++]; | |
1467 | base_offset = (base_offset << 7) + (c & 127); | |
1468 | } | |
1469 | base_offset = delta_obj_offset - base_offset; | |
1470 | if (base_offset <= 0 || base_offset >= delta_obj_offset) | |
1471 | return 0; /* out of bound */ | |
1472 | *curpos += used; | |
1473 | } else if (type == OBJ_REF_DELTA) { | |
1474 | /* The base entry _must_ be in the same pack */ | |
1475 | base_offset = find_pack_entry_one(base_info, p); | |
1476 | *curpos += 20; | |
1477 | } else | |
1478 | die("I am totally screwed"); | |
1479 | return base_offset; | |
1480 | } | |
1481 | ||
1482 | /* forward declaration for a mutually recursive function */ | |
1483 | static int packed_object_info(struct packed_git *p, off_t offset, | |
1484 | unsigned long *sizep, int *rtype); | |
1485 | ||
1486 | static int packed_delta_info(struct packed_git *p, | |
1487 | struct pack_window **w_curs, | |
1488 | off_t curpos, | |
1489 | enum object_type type, | |
1490 | off_t obj_offset, | |
1491 | unsigned long *sizep) | |
1492 | { | |
1493 | off_t base_offset; | |
1494 | ||
1495 | base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset); | |
1496 | if (!base_offset) | |
1497 | return OBJ_BAD; | |
1498 | type = packed_object_info(p, base_offset, NULL, NULL); | |
1499 | if (type <= OBJ_NONE) { | |
1500 | struct revindex_entry *revidx; | |
1501 | const unsigned char *base_sha1; | |
1502 | revidx = find_pack_revindex(p, base_offset); | |
1503 | if (!revidx) | |
1504 | return OBJ_BAD; | |
1505 | base_sha1 = nth_packed_object_sha1(p, revidx->nr); | |
1506 | mark_bad_packed_object(p, base_sha1); | |
1507 | type = sha1_object_info(base_sha1, NULL); | |
1508 | if (type <= OBJ_NONE) | |
1509 | return OBJ_BAD; | |
1510 | } | |
1511 | ||
1512 | /* We choose to only get the type of the base object and | |
1513 | * ignore potentially corrupt pack file that expects the delta | |
1514 | * based on a base with a wrong size. This saves tons of | |
1515 | * inflate() calls. | |
1516 | */ | |
1517 | if (sizep) { | |
1518 | *sizep = get_size_from_delta(p, w_curs, curpos); | |
1519 | if (*sizep == 0) | |
1520 | type = OBJ_BAD; | |
1521 | } | |
1522 | ||
1523 | return type; | |
1524 | } | |
1525 | ||
1526 | int unpack_object_header(struct packed_git *p, | |
1527 | struct pack_window **w_curs, | |
1528 | off_t *curpos, | |
1529 | unsigned long *sizep) | |
1530 | { | |
1531 | unsigned char *base; | |
1532 | unsigned int left; | |
1533 | unsigned long used; | |
1534 | enum object_type type; | |
1535 | ||
1536 | /* use_pack() assures us we have [base, base + 20) available | |
1537 | * as a range that we can look at. (Its actually the hash | |
1538 | * size that is assured.) With our object header encoding | |
1539 | * the maximum deflated object size is 2^137, which is just | |
1540 | * insane, so we know won't exceed what we have been given. | |
1541 | */ | |
1542 | base = use_pack(p, w_curs, *curpos, &left); | |
1543 | used = unpack_object_header_buffer(base, left, &type, sizep); | |
1544 | if (!used) { | |
1545 | type = OBJ_BAD; | |
1546 | } else | |
1547 | *curpos += used; | |
1548 | ||
1549 | return type; | |
1550 | } | |
1551 | ||
1552 | int packed_object_info_detail(struct packed_git *p, | |
1553 | off_t obj_offset, | |
1554 | unsigned long *size, | |
1555 | unsigned long *store_size, | |
1556 | unsigned int *delta_chain_length, | |
1557 | unsigned char *base_sha1) | |
1558 | { | |
1559 | struct pack_window *w_curs = NULL; | |
1560 | off_t curpos; | |
1561 | unsigned long dummy; | |
1562 | unsigned char *next_sha1; | |
1563 | enum object_type type; | |
1564 | struct revindex_entry *revidx; | |
1565 | ||
1566 | *delta_chain_length = 0; | |
1567 | curpos = obj_offset; | |
1568 | type = unpack_object_header(p, &w_curs, &curpos, size); | |
1569 | ||
1570 | revidx = find_pack_revindex(p, obj_offset); | |
1571 | *store_size = revidx[1].offset - obj_offset; | |
1572 | ||
1573 | for (;;) { | |
1574 | switch (type) { | |
1575 | default: | |
1576 | die("pack %s contains unknown object type %d", | |
1577 | p->pack_name, type); | |
1578 | case OBJ_COMMIT: | |
1579 | case OBJ_TREE: | |
1580 | case OBJ_BLOB: | |
1581 | case OBJ_TAG: | |
1582 | unuse_pack(&w_curs); | |
1583 | return type; | |
1584 | case OBJ_OFS_DELTA: | |
1585 | obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset); | |
1586 | if (!obj_offset) | |
1587 | die("pack %s contains bad delta base reference of type %s", | |
1588 | p->pack_name, typename(type)); | |
1589 | if (*delta_chain_length == 0) { | |
1590 | revidx = find_pack_revindex(p, obj_offset); | |
1591 | hashcpy(base_sha1, nth_packed_object_sha1(p, revidx->nr)); | |
1592 | } | |
1593 | break; | |
1594 | case OBJ_REF_DELTA: | |
1595 | next_sha1 = use_pack(p, &w_curs, curpos, NULL); | |
1596 | if (*delta_chain_length == 0) | |
1597 | hashcpy(base_sha1, next_sha1); | |
1598 | obj_offset = find_pack_entry_one(next_sha1, p); | |
1599 | break; | |
1600 | } | |
1601 | (*delta_chain_length)++; | |
1602 | curpos = obj_offset; | |
1603 | type = unpack_object_header(p, &w_curs, &curpos, &dummy); | |
1604 | } | |
1605 | } | |
1606 | ||
1607 | static int packed_object_info(struct packed_git *p, off_t obj_offset, | |
1608 | unsigned long *sizep, int *rtype) | |
1609 | { | |
1610 | struct pack_window *w_curs = NULL; | |
1611 | unsigned long size; | |
1612 | off_t curpos = obj_offset; | |
1613 | enum object_type type; | |
1614 | ||
1615 | type = unpack_object_header(p, &w_curs, &curpos, &size); | |
1616 | if (rtype) | |
1617 | *rtype = type; /* representation type */ | |
1618 | ||
1619 | switch (type) { | |
1620 | case OBJ_OFS_DELTA: | |
1621 | case OBJ_REF_DELTA: | |
1622 | type = packed_delta_info(p, &w_curs, curpos, | |
1623 | type, obj_offset, sizep); | |
1624 | break; | |
1625 | case OBJ_COMMIT: | |
1626 | case OBJ_TREE: | |
1627 | case OBJ_BLOB: | |
1628 | case OBJ_TAG: | |
1629 | if (sizep) | |
1630 | *sizep = size; | |
1631 | break; | |
1632 | default: | |
1633 | error("unknown object type %i at offset %"PRIuMAX" in %s", | |
1634 | type, (uintmax_t)obj_offset, p->pack_name); | |
1635 | type = OBJ_BAD; | |
1636 | } | |
1637 | unuse_pack(&w_curs); | |
1638 | return type; | |
1639 | } | |
1640 | ||
1641 | static void *unpack_compressed_entry(struct packed_git *p, | |
1642 | struct pack_window **w_curs, | |
1643 | off_t curpos, | |
1644 | unsigned long size) | |
1645 | { | |
1646 | int st; | |
1647 | z_stream stream; | |
1648 | unsigned char *buffer, *in; | |
1649 | ||
1650 | buffer = xmallocz(size); | |
1651 | memset(&stream, 0, sizeof(stream)); | |
1652 | stream.next_out = buffer; | |
1653 | stream.avail_out = size + 1; | |
1654 | ||
1655 | git_inflate_init(&stream); | |
1656 | do { | |
1657 | in = use_pack(p, w_curs, curpos, &stream.avail_in); | |
1658 | stream.next_in = in; | |
1659 | st = git_inflate(&stream, Z_FINISH); | |
1660 | if (!stream.avail_out) | |
1661 | break; /* the payload is larger than it should be */ | |
1662 | curpos += stream.next_in - in; | |
1663 | } while (st == Z_OK || st == Z_BUF_ERROR); | |
1664 | git_inflate_end(&stream); | |
1665 | if ((st != Z_STREAM_END) || stream.total_out != size) { | |
1666 | free(buffer); | |
1667 | return NULL; | |
1668 | } | |
1669 | ||
1670 | return buffer; | |
1671 | } | |
1672 | ||
1673 | #define MAX_DELTA_CACHE (256) | |
1674 | ||
1675 | static size_t delta_base_cached; | |
1676 | ||
1677 | static struct delta_base_cache_lru_list { | |
1678 | struct delta_base_cache_lru_list *prev; | |
1679 | struct delta_base_cache_lru_list *next; | |
1680 | } delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru }; | |
1681 | ||
1682 | static struct delta_base_cache_entry { | |
1683 | struct delta_base_cache_lru_list lru; | |
1684 | void *data; | |
1685 | struct packed_git *p; | |
1686 | off_t base_offset; | |
1687 | unsigned long size; | |
1688 | enum object_type type; | |
1689 | } delta_base_cache[MAX_DELTA_CACHE]; | |
1690 | ||
1691 | static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset) | |
1692 | { | |
1693 | unsigned long hash; | |
1694 | ||
1695 | hash = (unsigned long)p + (unsigned long)base_offset; | |
1696 | hash += (hash >> 8) + (hash >> 16); | |
1697 | return hash % MAX_DELTA_CACHE; | |
1698 | } | |
1699 | ||
1700 | static int in_delta_base_cache(struct packed_git *p, off_t base_offset) | |
1701 | { | |
1702 | unsigned long hash = pack_entry_hash(p, base_offset); | |
1703 | struct delta_base_cache_entry *ent = delta_base_cache + hash; | |
1704 | return (ent->data && ent->p == p && ent->base_offset == base_offset); | |
1705 | } | |
1706 | ||
1707 | static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset, | |
1708 | unsigned long *base_size, enum object_type *type, int keep_cache) | |
1709 | { | |
1710 | void *ret; | |
1711 | unsigned long hash = pack_entry_hash(p, base_offset); | |
1712 | struct delta_base_cache_entry *ent = delta_base_cache + hash; | |
1713 | ||
1714 | ret = ent->data; | |
1715 | if (!ret || ent->p != p || ent->base_offset != base_offset) | |
1716 | return unpack_entry(p, base_offset, type, base_size); | |
1717 | ||
1718 | if (!keep_cache) { | |
1719 | ent->data = NULL; | |
1720 | ent->lru.next->prev = ent->lru.prev; | |
1721 | ent->lru.prev->next = ent->lru.next; | |
1722 | delta_base_cached -= ent->size; | |
1723 | } else { | |
1724 | ret = xmemdupz(ent->data, ent->size); | |
1725 | } | |
1726 | *type = ent->type; | |
1727 | *base_size = ent->size; | |
1728 | return ret; | |
1729 | } | |
1730 | ||
1731 | static inline void release_delta_base_cache(struct delta_base_cache_entry *ent) | |
1732 | { | |
1733 | if (ent->data) { | |
1734 | free(ent->data); | |
1735 | ent->data = NULL; | |
1736 | ent->lru.next->prev = ent->lru.prev; | |
1737 | ent->lru.prev->next = ent->lru.next; | |
1738 | delta_base_cached -= ent->size; | |
1739 | } | |
1740 | } | |
1741 | ||
1742 | void clear_delta_base_cache(void) | |
1743 | { | |
1744 | unsigned long p; | |
1745 | for (p = 0; p < MAX_DELTA_CACHE; p++) | |
1746 | release_delta_base_cache(&delta_base_cache[p]); | |
1747 | } | |
1748 | ||
1749 | static void add_delta_base_cache(struct packed_git *p, off_t base_offset, | |
1750 | void *base, unsigned long base_size, enum object_type type) | |
1751 | { | |
1752 | unsigned long hash = pack_entry_hash(p, base_offset); | |
1753 | struct delta_base_cache_entry *ent = delta_base_cache + hash; | |
1754 | struct delta_base_cache_lru_list *lru; | |
1755 | ||
1756 | release_delta_base_cache(ent); | |
1757 | delta_base_cached += base_size; | |
1758 | ||
1759 | for (lru = delta_base_cache_lru.next; | |
1760 | delta_base_cached > delta_base_cache_limit | |
1761 | && lru != &delta_base_cache_lru; | |
1762 | lru = lru->next) { | |
1763 | struct delta_base_cache_entry *f = (void *)lru; | |
1764 | if (f->type == OBJ_BLOB) | |
1765 | release_delta_base_cache(f); | |
1766 | } | |
1767 | for (lru = delta_base_cache_lru.next; | |
1768 | delta_base_cached > delta_base_cache_limit | |
1769 | && lru != &delta_base_cache_lru; | |
1770 | lru = lru->next) { | |
1771 | struct delta_base_cache_entry *f = (void *)lru; | |
1772 | release_delta_base_cache(f); | |
1773 | } | |
1774 | ||
1775 | ent->p = p; | |
1776 | ent->base_offset = base_offset; | |
1777 | ent->type = type; | |
1778 | ent->data = base; | |
1779 | ent->size = base_size; | |
1780 | ent->lru.next = &delta_base_cache_lru; | |
1781 | ent->lru.prev = delta_base_cache_lru.prev; | |
1782 | delta_base_cache_lru.prev->next = &ent->lru; | |
1783 | delta_base_cache_lru.prev = &ent->lru; | |
1784 | } | |
1785 | ||
1786 | static void *read_object(const unsigned char *sha1, enum object_type *type, | |
1787 | unsigned long *size); | |
1788 | ||
1789 | static void *unpack_delta_entry(struct packed_git *p, | |
1790 | struct pack_window **w_curs, | |
1791 | off_t curpos, | |
1792 | unsigned long delta_size, | |
1793 | off_t obj_offset, | |
1794 | enum object_type *type, | |
1795 | unsigned long *sizep) | |
1796 | { | |
1797 | void *delta_data, *result, *base; | |
1798 | unsigned long base_size; | |
1799 | off_t base_offset; | |
1800 | ||
1801 | base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset); | |
1802 | if (!base_offset) { | |
1803 | error("failed to validate delta base reference " | |
1804 | "at offset %"PRIuMAX" from %s", | |
1805 | (uintmax_t)curpos, p->pack_name); | |
1806 | return NULL; | |
1807 | } | |
1808 | unuse_pack(w_curs); | |
1809 | base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0); | |
1810 | if (!base) { | |
1811 | /* | |
1812 | * We're probably in deep shit, but let's try to fetch | |
1813 | * the required base anyway from another pack or loose. | |
1814 | * This is costly but should happen only in the presence | |
1815 | * of a corrupted pack, and is better than failing outright. | |
1816 | */ | |
1817 | struct revindex_entry *revidx; | |
1818 | const unsigned char *base_sha1; | |
1819 | revidx = find_pack_revindex(p, base_offset); | |
1820 | if (!revidx) | |
1821 | return NULL; | |
1822 | base_sha1 = nth_packed_object_sha1(p, revidx->nr); | |
1823 | error("failed to read delta base object %s" | |
1824 | " at offset %"PRIuMAX" from %s", | |
1825 | sha1_to_hex(base_sha1), (uintmax_t)base_offset, | |
1826 | p->pack_name); | |
1827 | mark_bad_packed_object(p, base_sha1); | |
1828 | base = read_object(base_sha1, type, &base_size); | |
1829 | if (!base) | |
1830 | return NULL; | |
1831 | } | |
1832 | ||
1833 | delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size); | |
1834 | if (!delta_data) { | |
1835 | error("failed to unpack compressed delta " | |
1836 | "at offset %"PRIuMAX" from %s", | |
1837 | (uintmax_t)curpos, p->pack_name); | |
1838 | free(base); | |
1839 | return NULL; | |
1840 | } | |
1841 | result = patch_delta(base, base_size, | |
1842 | delta_data, delta_size, | |
1843 | sizep); | |
1844 | if (!result) | |
1845 | die("failed to apply delta"); | |
1846 | free(delta_data); | |
1847 | add_delta_base_cache(p, base_offset, base, base_size, *type); | |
1848 | return result; | |
1849 | } | |
1850 | ||
1851 | int do_check_packed_object_crc; | |
1852 | ||
1853 | void *unpack_entry(struct packed_git *p, off_t obj_offset, | |
1854 | enum object_type *type, unsigned long *sizep) | |
1855 | { | |
1856 | struct pack_window *w_curs = NULL; | |
1857 | off_t curpos = obj_offset; | |
1858 | void *data; | |
1859 | ||
1860 | if (do_check_packed_object_crc && p->index_version > 1) { | |
1861 | struct revindex_entry *revidx = find_pack_revindex(p, obj_offset); | |
1862 | unsigned long len = revidx[1].offset - obj_offset; | |
1863 | if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) { | |
1864 | const unsigned char *sha1 = | |
1865 | nth_packed_object_sha1(p, revidx->nr); | |
1866 | error("bad packed object CRC for %s", | |
1867 | sha1_to_hex(sha1)); | |
1868 | mark_bad_packed_object(p, sha1); | |
1869 | unuse_pack(&w_curs); | |
1870 | return NULL; | |
1871 | } | |
1872 | } | |
1873 | ||
1874 | *type = unpack_object_header(p, &w_curs, &curpos, sizep); | |
1875 | switch (*type) { | |
1876 | case OBJ_OFS_DELTA: | |
1877 | case OBJ_REF_DELTA: | |
1878 | data = unpack_delta_entry(p, &w_curs, curpos, *sizep, | |
1879 | obj_offset, type, sizep); | |
1880 | break; | |
1881 | case OBJ_COMMIT: | |
1882 | case OBJ_TREE: | |
1883 | case OBJ_BLOB: | |
1884 | case OBJ_TAG: | |
1885 | data = unpack_compressed_entry(p, &w_curs, curpos, *sizep); | |
1886 | break; | |
1887 | default: | |
1888 | data = NULL; | |
1889 | error("unknown object type %i at offset %"PRIuMAX" in %s", | |
1890 | *type, (uintmax_t)obj_offset, p->pack_name); | |
1891 | } | |
1892 | unuse_pack(&w_curs); | |
1893 | return data; | |
1894 | } | |
1895 | ||
1896 | const unsigned char *nth_packed_object_sha1(struct packed_git *p, | |
1897 | uint32_t n) | |
1898 | { | |
1899 | const unsigned char *index = p->index_data; | |
1900 | if (!index) { | |
1901 | if (open_pack_index(p)) | |
1902 | return NULL; | |
1903 | index = p->index_data; | |
1904 | } | |
1905 | if (n >= p->num_objects) | |
1906 | return NULL; | |
1907 | index += 4 * 256; | |
1908 | if (p->index_version == 1) { | |
1909 | return index + 24 * n + 4; | |
1910 | } else { | |
1911 | index += 8; | |
1912 | return index + 20 * n; | |
1913 | } | |
1914 | } | |
1915 | ||
1916 | off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n) | |
1917 | { | |
1918 | const unsigned char *index = p->index_data; | |
1919 | index += 4 * 256; | |
1920 | if (p->index_version == 1) { | |
1921 | return ntohl(*((uint32_t *)(index + 24 * n))); | |
1922 | } else { | |
1923 | uint32_t off; | |
1924 | index += 8 + p->num_objects * (20 + 4); | |
1925 | off = ntohl(*((uint32_t *)(index + 4 * n))); | |
1926 | if (!(off & 0x80000000)) | |
1927 | return off; | |
1928 | index += p->num_objects * 4 + (off & 0x7fffffff) * 8; | |
1929 | return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) | | |
1930 | ntohl(*((uint32_t *)(index + 4))); | |
1931 | } | |
1932 | } | |
1933 | ||
1934 | off_t find_pack_entry_one(const unsigned char *sha1, | |
1935 | struct packed_git *p) | |
1936 | { | |
1937 | const uint32_t *level1_ofs = p->index_data; | |
1938 | const unsigned char *index = p->index_data; | |
1939 | unsigned hi, lo, stride; | |
1940 | static int use_lookup = -1; | |
1941 | static int debug_lookup = -1; | |
1942 | ||
1943 | if (debug_lookup < 0) | |
1944 | debug_lookup = !!getenv("GIT_DEBUG_LOOKUP"); | |
1945 | ||
1946 | if (!index) { | |
1947 | if (open_pack_index(p)) | |
1948 | return 0; | |
1949 | level1_ofs = p->index_data; | |
1950 | index = p->index_data; | |
1951 | } | |
1952 | if (p->index_version > 1) { | |
1953 | level1_ofs += 2; | |
1954 | index += 8; | |
1955 | } | |
1956 | index += 4 * 256; | |
1957 | hi = ntohl(level1_ofs[*sha1]); | |
1958 | lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1])); | |
1959 | if (p->index_version > 1) { | |
1960 | stride = 20; | |
1961 | } else { | |
1962 | stride = 24; | |
1963 | index += 4; | |
1964 | } | |
1965 | ||
1966 | if (debug_lookup) | |
1967 | printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n", | |
1968 | sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects); | |
1969 | ||
1970 | if (use_lookup < 0) | |
1971 | use_lookup = !!getenv("GIT_USE_LOOKUP"); | |
1972 | if (use_lookup) { | |
1973 | int pos = sha1_entry_pos(index, stride, 0, | |
1974 | lo, hi, p->num_objects, sha1); | |
1975 | if (pos < 0) | |
1976 | return 0; | |
1977 | return nth_packed_object_offset(p, pos); | |
1978 | } | |
1979 | ||
1980 | do { | |
1981 | unsigned mi = (lo + hi) / 2; | |
1982 | int cmp = hashcmp(index + mi * stride, sha1); | |
1983 | ||
1984 | if (debug_lookup) | |
1985 | printf("lo %u hi %u rg %u mi %u\n", | |
1986 | lo, hi, hi - lo, mi); | |
1987 | if (!cmp) | |
1988 | return nth_packed_object_offset(p, mi); | |
1989 | if (cmp > 0) | |
1990 | hi = mi; | |
1991 | else | |
1992 | lo = mi+1; | |
1993 | } while (lo < hi); | |
1994 | return 0; | |
1995 | } | |
1996 | ||
1997 | static int is_pack_valid(struct packed_git *p) | |
1998 | { | |
1999 | /* An already open pack is known to be valid. */ | |
2000 | if (p->pack_fd != -1) | |
2001 | return 1; | |
2002 | ||
2003 | /* If the pack has one window completely covering the | |
2004 | * file size, the pack is known to be valid even if | |
2005 | * the descriptor is not currently open. | |
2006 | */ | |
2007 | if (p->windows) { | |
2008 | struct pack_window *w = p->windows; | |
2009 | ||
2010 | if (!w->offset && w->len == p->pack_size) | |
2011 | return 1; | |
2012 | } | |
2013 | ||
2014 | /* Force the pack to open to prove its valid. */ | |
2015 | return !open_packed_git(p); | |
2016 | } | |
2017 | ||
2018 | static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e) | |
2019 | { | |
2020 | static struct packed_git *last_found = (void *)1; | |
2021 | struct packed_git *p; | |
2022 | off_t offset; | |
2023 | ||
2024 | prepare_packed_git(); | |
2025 | if (!packed_git) | |
2026 | return 0; | |
2027 | p = (last_found == (void *)1) ? packed_git : last_found; | |
2028 | ||
2029 | do { | |
2030 | if (p->num_bad_objects) { | |
2031 | unsigned i; | |
2032 | for (i = 0; i < p->num_bad_objects; i++) | |
2033 | if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) | |
2034 | goto next; | |
2035 | } | |
2036 | ||
2037 | offset = find_pack_entry_one(sha1, p); | |
2038 | if (offset) { | |
2039 | /* | |
2040 | * We are about to tell the caller where they can | |
2041 | * locate the requested object. We better make | |
2042 | * sure the packfile is still here and can be | |
2043 | * accessed before supplying that answer, as | |
2044 | * it may have been deleted since the index | |
2045 | * was loaded! | |
2046 | */ | |
2047 | if (!is_pack_valid(p)) { | |
2048 | error("packfile %s cannot be accessed", p->pack_name); | |
2049 | goto next; | |
2050 | } | |
2051 | e->offset = offset; | |
2052 | e->p = p; | |
2053 | hashcpy(e->sha1, sha1); | |
2054 | last_found = p; | |
2055 | return 1; | |
2056 | } | |
2057 | ||
2058 | next: | |
2059 | if (p == last_found) | |
2060 | p = packed_git; | |
2061 | else | |
2062 | p = p->next; | |
2063 | if (p == last_found) | |
2064 | p = p->next; | |
2065 | } while (p); | |
2066 | return 0; | |
2067 | } | |
2068 | ||
2069 | struct packed_git *find_sha1_pack(const unsigned char *sha1, | |
2070 | struct packed_git *packs) | |
2071 | { | |
2072 | struct packed_git *p; | |
2073 | ||
2074 | for (p = packs; p; p = p->next) { | |
2075 | if (find_pack_entry_one(sha1, p)) | |
2076 | return p; | |
2077 | } | |
2078 | return NULL; | |
2079 | ||
2080 | } | |
2081 | ||
2082 | static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep) | |
2083 | { | |
2084 | int status; | |
2085 | unsigned long mapsize, size; | |
2086 | void *map; | |
2087 | z_stream stream; | |
2088 | char hdr[32]; | |
2089 | ||
2090 | map = map_sha1_file(sha1, &mapsize); | |
2091 | if (!map) | |
2092 | return error("unable to find %s", sha1_to_hex(sha1)); | |
2093 | if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) | |
2094 | status = error("unable to unpack %s header", | |
2095 | sha1_to_hex(sha1)); | |
2096 | else if ((status = parse_sha1_header(hdr, &size)) < 0) | |
2097 | status = error("unable to parse %s header", sha1_to_hex(sha1)); | |
2098 | else if (sizep) | |
2099 | *sizep = size; | |
2100 | git_inflate_end(&stream); | |
2101 | munmap(map, mapsize); | |
2102 | return status; | |
2103 | } | |
2104 | ||
2105 | /* returns enum object_type or negative */ | |
2106 | int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi) | |
2107 | { | |
2108 | struct cached_object *co; | |
2109 | struct pack_entry e; | |
2110 | int status, rtype; | |
2111 | ||
2112 | co = find_cached_object(sha1); | |
2113 | if (co) { | |
2114 | if (oi->sizep) | |
2115 | *(oi->sizep) = co->size; | |
2116 | oi->whence = OI_CACHED; | |
2117 | return co->type; | |
2118 | } | |
2119 | ||
2120 | if (!find_pack_entry(sha1, &e)) { | |
2121 | /* Most likely it's a loose object. */ | |
2122 | status = sha1_loose_object_info(sha1, oi->sizep); | |
2123 | if (status >= 0) { | |
2124 | oi->whence = OI_LOOSE; | |
2125 | return status; | |
2126 | } | |
2127 | ||
2128 | /* Not a loose object; someone else may have just packed it. */ | |
2129 | reprepare_packed_git(); | |
2130 | if (!find_pack_entry(sha1, &e)) | |
2131 | return status; | |
2132 | } | |
2133 | ||
2134 | status = packed_object_info(e.p, e.offset, oi->sizep, &rtype); | |
2135 | if (status < 0) { | |
2136 | mark_bad_packed_object(e.p, sha1); | |
2137 | status = sha1_object_info_extended(sha1, oi); | |
2138 | } else if (in_delta_base_cache(e.p, e.offset)) { | |
2139 | oi->whence = OI_DBCACHED; | |
2140 | } else { | |
2141 | oi->whence = OI_PACKED; | |
2142 | oi->u.packed.offset = e.offset; | |
2143 | oi->u.packed.pack = e.p; | |
2144 | oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA || | |
2145 | rtype == OBJ_OFS_DELTA); | |
2146 | } | |
2147 | ||
2148 | return status; | |
2149 | } | |
2150 | ||
2151 | int sha1_object_info(const unsigned char *sha1, unsigned long *sizep) | |
2152 | { | |
2153 | struct object_info oi; | |
2154 | ||
2155 | oi.sizep = sizep; | |
2156 | return sha1_object_info_extended(sha1, &oi); | |
2157 | } | |
2158 | ||
2159 | static void *read_packed_sha1(const unsigned char *sha1, | |
2160 | enum object_type *type, unsigned long *size) | |
2161 | { | |
2162 | struct pack_entry e; | |
2163 | void *data; | |
2164 | ||
2165 | if (!find_pack_entry(sha1, &e)) | |
2166 | return NULL; | |
2167 | data = cache_or_unpack_entry(e.p, e.offset, size, type, 1); | |
2168 | if (!data) { | |
2169 | /* | |
2170 | * We're probably in deep shit, but let's try to fetch | |
2171 | * the required object anyway from another pack or loose. | |
2172 | * This should happen only in the presence of a corrupted | |
2173 | * pack, and is better than failing outright. | |
2174 | */ | |
2175 | error("failed to read object %s at offset %"PRIuMAX" from %s", | |
2176 | sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name); | |
2177 | mark_bad_packed_object(e.p, sha1); | |
2178 | data = read_object(sha1, type, size); | |
2179 | } | |
2180 | return data; | |
2181 | } | |
2182 | ||
2183 | int pretend_sha1_file(void *buf, unsigned long len, enum object_type type, | |
2184 | unsigned char *sha1) | |
2185 | { | |
2186 | struct cached_object *co; | |
2187 | ||
2188 | hash_sha1_file(buf, len, typename(type), sha1); | |
2189 | if (has_sha1_file(sha1) || find_cached_object(sha1)) | |
2190 | return 0; | |
2191 | if (cached_object_alloc <= cached_object_nr) { | |
2192 | cached_object_alloc = alloc_nr(cached_object_alloc); | |
2193 | cached_objects = xrealloc(cached_objects, | |
2194 | sizeof(*cached_objects) * | |
2195 | cached_object_alloc); | |
2196 | } | |
2197 | co = &cached_objects[cached_object_nr++]; | |
2198 | co->size = len; | |
2199 | co->type = type; | |
2200 | co->buf = xmalloc(len); | |
2201 | memcpy(co->buf, buf, len); | |
2202 | hashcpy(co->sha1, sha1); | |
2203 | return 0; | |
2204 | } | |
2205 | ||
2206 | static void *read_object(const unsigned char *sha1, enum object_type *type, | |
2207 | unsigned long *size) | |
2208 | { | |
2209 | unsigned long mapsize; | |
2210 | void *map, *buf; | |
2211 | struct cached_object *co; | |
2212 | ||
2213 | co = find_cached_object(sha1); | |
2214 | if (co) { | |
2215 | *type = co->type; | |
2216 | *size = co->size; | |
2217 | return xmemdupz(co->buf, co->size); | |
2218 | } | |
2219 | ||
2220 | buf = read_packed_sha1(sha1, type, size); | |
2221 | if (buf) | |
2222 | return buf; | |
2223 | map = map_sha1_file(sha1, &mapsize); | |
2224 | if (map) { | |
2225 | buf = unpack_sha1_file(map, mapsize, type, size, sha1); | |
2226 | munmap(map, mapsize); | |
2227 | return buf; | |
2228 | } | |
2229 | reprepare_packed_git(); | |
2230 | return read_packed_sha1(sha1, type, size); | |
2231 | } | |
2232 | ||
2233 | /* | |
2234 | * This function dies on corrupt objects; the callers who want to | |
2235 | * deal with them should arrange to call read_object() and give error | |
2236 | * messages themselves. | |
2237 | */ | |
2238 | void *read_sha1_file_extended(const unsigned char *sha1, | |
2239 | enum object_type *type, | |
2240 | unsigned long *size, | |
2241 | unsigned flag) | |
2242 | { | |
2243 | void *data; | |
2244 | char *path; | |
2245 | const struct packed_git *p; | |
2246 | const unsigned char *repl = (flag & READ_SHA1_FILE_REPLACE) | |
2247 | ? lookup_replace_object(sha1) : sha1; | |
2248 | ||
2249 | errno = 0; | |
2250 | data = read_object(repl, type, size); | |
2251 | if (data) | |
2252 | return data; | |
2253 | ||
2254 | if (errno && errno != ENOENT) | |
2255 | die_errno("failed to read object %s", sha1_to_hex(sha1)); | |
2256 | ||
2257 | /* die if we replaced an object with one that does not exist */ | |
2258 | if (repl != sha1) | |
2259 | die("replacement %s not found for %s", | |
2260 | sha1_to_hex(repl), sha1_to_hex(sha1)); | |
2261 | ||
2262 | if (has_loose_object(repl)) { | |
2263 | path = sha1_file_name(sha1); | |
2264 | die("loose object %s (stored in %s) is corrupt", | |
2265 | sha1_to_hex(repl), path); | |
2266 | } | |
2267 | ||
2268 | if ((p = has_packed_and_bad(repl)) != NULL) | |
2269 | die("packed object %s (stored in %s) is corrupt", | |
2270 | sha1_to_hex(repl), p->pack_name); | |
2271 | ||
2272 | return NULL; | |
2273 | } | |
2274 | ||
2275 | void *read_object_with_reference(const unsigned char *sha1, | |
2276 | const char *required_type_name, | |
2277 | unsigned long *size, | |
2278 | unsigned char *actual_sha1_return) | |
2279 | { | |
2280 | enum object_type type, required_type; | |
2281 | void *buffer; | |
2282 | unsigned long isize; | |
2283 | unsigned char actual_sha1[20]; | |
2284 | ||
2285 | required_type = type_from_string(required_type_name); | |
2286 | hashcpy(actual_sha1, sha1); | |
2287 | while (1) { | |
2288 | int ref_length = -1; | |
2289 | const char *ref_type = NULL; | |
2290 | ||
2291 | buffer = read_sha1_file(actual_sha1, &type, &isize); | |
2292 | if (!buffer) | |
2293 | return NULL; | |
2294 | if (type == required_type) { | |
2295 | *size = isize; | |
2296 | if (actual_sha1_return) | |
2297 | hashcpy(actual_sha1_return, actual_sha1); | |
2298 | return buffer; | |
2299 | } | |
2300 | /* Handle references */ | |
2301 | else if (type == OBJ_COMMIT) | |
2302 | ref_type = "tree "; | |
2303 | else if (type == OBJ_TAG) | |
2304 | ref_type = "object "; | |
2305 | else { | |
2306 | free(buffer); | |
2307 | return NULL; | |
2308 | } | |
2309 | ref_length = strlen(ref_type); | |
2310 | ||
2311 | if (ref_length + 40 > isize || | |
2312 | memcmp(buffer, ref_type, ref_length) || | |
2313 | get_sha1_hex((char *) buffer + ref_length, actual_sha1)) { | |
2314 | free(buffer); | |
2315 | return NULL; | |
2316 | } | |
2317 | free(buffer); | |
2318 | /* Now we have the ID of the referred-to object in | |
2319 | * actual_sha1. Check again. */ | |
2320 | } | |
2321 | } | |
2322 | ||
2323 | static void write_sha1_file_prepare(const void *buf, unsigned long len, | |
2324 | const char *type, unsigned char *sha1, | |
2325 | char *hdr, int *hdrlen) | |
2326 | { | |
2327 | git_SHA_CTX c; | |
2328 | ||
2329 | /* Generate the header */ | |
2330 | *hdrlen = sprintf(hdr, "%s %lu", type, len)+1; | |
2331 | ||
2332 | /* Sha1.. */ | |
2333 | git_SHA1_Init(&c); | |
2334 | git_SHA1_Update(&c, hdr, *hdrlen); | |
2335 | git_SHA1_Update(&c, buf, len); | |
2336 | git_SHA1_Final(sha1, &c); | |
2337 | } | |
2338 | ||
2339 | /* | |
2340 | * Move the just written object into its final resting place. | |
2341 | * NEEDSWORK: this should be renamed to finalize_temp_file() as | |
2342 | * "moving" is only a part of what it does, when no patch between | |
2343 | * master to pu changes the call sites of this function. | |
2344 | */ | |
2345 | int move_temp_to_file(const char *tmpfile, const char *filename) | |
2346 | { | |
2347 | int ret = 0; | |
2348 | ||
2349 | if (object_creation_mode == OBJECT_CREATION_USES_RENAMES) | |
2350 | goto try_rename; | |
2351 | else if (link(tmpfile, filename)) | |
2352 | ret = errno; | |
2353 | ||
2354 | /* | |
2355 | * Coda hack - coda doesn't like cross-directory links, | |
2356 | * so we fall back to a rename, which will mean that it | |
2357 | * won't be able to check collisions, but that's not a | |
2358 | * big deal. | |
2359 | * | |
2360 | * The same holds for FAT formatted media. | |
2361 | * | |
2362 | * When this succeeds, we just return. We have nothing | |
2363 | * left to unlink. | |
2364 | */ | |
2365 | if (ret && ret != EEXIST) { | |
2366 | try_rename: | |
2367 | if (!rename(tmpfile, filename)) | |
2368 | goto out; | |
2369 | ret = errno; | |
2370 | } | |
2371 | unlink_or_warn(tmpfile); | |
2372 | if (ret) { | |
2373 | if (ret != EEXIST) { | |
2374 | return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret)); | |
2375 | } | |
2376 | /* FIXME!!! Collision check here ? */ | |
2377 | } | |
2378 | ||
2379 | out: | |
2380 | if (adjust_shared_perm(filename)) | |
2381 | return error("unable to set permission to '%s'", filename); | |
2382 | return 0; | |
2383 | } | |
2384 | ||
2385 | static int write_buffer(int fd, const void *buf, size_t len) | |
2386 | { | |
2387 | if (write_in_full(fd, buf, len) < 0) | |
2388 | return error("file write error (%s)", strerror(errno)); | |
2389 | return 0; | |
2390 | } | |
2391 | ||
2392 | int hash_sha1_file(const void *buf, unsigned long len, const char *type, | |
2393 | unsigned char *sha1) | |
2394 | { | |
2395 | char hdr[32]; | |
2396 | int hdrlen; | |
2397 | write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); | |
2398 | return 0; | |
2399 | } | |
2400 | ||
2401 | /* Finalize a file on disk, and close it. */ | |
2402 | static void close_sha1_file(int fd) | |
2403 | { | |
2404 | if (fsync_object_files) | |
2405 | fsync_or_die(fd, "sha1 file"); | |
2406 | if (close(fd) != 0) | |
2407 | die_errno("error when closing sha1 file"); | |
2408 | } | |
2409 | ||
2410 | /* Size of directory component, including the ending '/' */ | |
2411 | static inline int directory_size(const char *filename) | |
2412 | { | |
2413 | const char *s = strrchr(filename, '/'); | |
2414 | if (!s) | |
2415 | return 0; | |
2416 | return s - filename + 1; | |
2417 | } | |
2418 | ||
2419 | /* | |
2420 | * This creates a temporary file in the same directory as the final | |
2421 | * 'filename' | |
2422 | * | |
2423 | * We want to avoid cross-directory filename renames, because those | |
2424 | * can have problems on various filesystems (FAT, NFS, Coda). | |
2425 | */ | |
2426 | static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename) | |
2427 | { | |
2428 | int fd, dirlen = directory_size(filename); | |
2429 | ||
2430 | if (dirlen + 20 > bufsiz) { | |
2431 | errno = ENAMETOOLONG; | |
2432 | return -1; | |
2433 | } | |
2434 | memcpy(buffer, filename, dirlen); | |
2435 | strcpy(buffer + dirlen, "tmp_obj_XXXXXX"); | |
2436 | fd = git_mkstemp_mode(buffer, 0444); | |
2437 | if (fd < 0 && dirlen && errno == ENOENT) { | |
2438 | /* Make sure the directory exists */ | |
2439 | memcpy(buffer, filename, dirlen); | |
2440 | buffer[dirlen-1] = 0; | |
2441 | if (mkdir(buffer, 0777) || adjust_shared_perm(buffer)) | |
2442 | return -1; | |
2443 | ||
2444 | /* Try again */ | |
2445 | strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX"); | |
2446 | fd = git_mkstemp_mode(buffer, 0444); | |
2447 | } | |
2448 | return fd; | |
2449 | } | |
2450 | ||
2451 | static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen, | |
2452 | const void *buf, unsigned long len, time_t mtime) | |
2453 | { | |
2454 | int fd, ret; | |
2455 | unsigned char compressed[4096]; | |
2456 | z_stream stream; | |
2457 | git_SHA_CTX c; | |
2458 | unsigned char parano_sha1[20]; | |
2459 | char *filename; | |
2460 | static char tmpfile[PATH_MAX]; | |
2461 | ||
2462 | filename = sha1_file_name(sha1); | |
2463 | fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename); | |
2464 | if (fd < 0) { | |
2465 | if (errno == EACCES) | |
2466 | return error("insufficient permission for adding an object to repository database %s\n", get_object_directory()); | |
2467 | else | |
2468 | return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno)); | |
2469 | } | |
2470 | ||
2471 | /* Set it up */ | |
2472 | memset(&stream, 0, sizeof(stream)); | |
2473 | deflateInit(&stream, zlib_compression_level); | |
2474 | stream.next_out = compressed; | |
2475 | stream.avail_out = sizeof(compressed); | |
2476 | git_SHA1_Init(&c); | |
2477 | ||
2478 | /* First header.. */ | |
2479 | stream.next_in = (unsigned char *)hdr; | |
2480 | stream.avail_in = hdrlen; | |
2481 | while (deflate(&stream, 0) == Z_OK) | |
2482 | /* nothing */; | |
2483 | git_SHA1_Update(&c, hdr, hdrlen); | |
2484 | ||
2485 | /* Then the data itself.. */ | |
2486 | stream.next_in = (void *)buf; | |
2487 | stream.avail_in = len; | |
2488 | do { | |
2489 | unsigned char *in0 = stream.next_in; | |
2490 | ret = deflate(&stream, Z_FINISH); | |
2491 | git_SHA1_Update(&c, in0, stream.next_in - in0); | |
2492 | if (write_buffer(fd, compressed, stream.next_out - compressed) < 0) | |
2493 | die("unable to write sha1 file"); | |
2494 | stream.next_out = compressed; | |
2495 | stream.avail_out = sizeof(compressed); | |
2496 | } while (ret == Z_OK); | |
2497 | ||
2498 | if (ret != Z_STREAM_END) | |
2499 | die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret); | |
2500 | ret = deflateEnd(&stream); | |
2501 | if (ret != Z_OK) | |
2502 | die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret); | |
2503 | git_SHA1_Final(parano_sha1, &c); | |
2504 | if (hashcmp(sha1, parano_sha1) != 0) | |
2505 | die("confused by unstable object source data for %s", sha1_to_hex(sha1)); | |
2506 | ||
2507 | close_sha1_file(fd); | |
2508 | ||
2509 | if (mtime) { | |
2510 | struct utimbuf utb; | |
2511 | utb.actime = mtime; | |
2512 | utb.modtime = mtime; | |
2513 | if (utime(tmpfile, &utb) < 0) | |
2514 | warning("failed utime() on %s: %s", | |
2515 | tmpfile, strerror(errno)); | |
2516 | } | |
2517 | ||
2518 | return move_temp_to_file(tmpfile, filename); | |
2519 | } | |
2520 | ||
2521 | int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *returnsha1) | |
2522 | { | |
2523 | unsigned char sha1[20]; | |
2524 | char hdr[32]; | |
2525 | int hdrlen; | |
2526 | ||
2527 | /* Normally if we have it in the pack then we do not bother writing | |
2528 | * it out into .git/objects/??/?{38} file. | |
2529 | */ | |
2530 | write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); | |
2531 | if (returnsha1) | |
2532 | hashcpy(returnsha1, sha1); | |
2533 | if (has_sha1_file(sha1)) | |
2534 | return 0; | |
2535 | return write_loose_object(sha1, hdr, hdrlen, buf, len, 0); | |
2536 | } | |
2537 | ||
2538 | int force_object_loose(const unsigned char *sha1, time_t mtime) | |
2539 | { | |
2540 | void *buf; | |
2541 | unsigned long len; | |
2542 | enum object_type type; | |
2543 | char hdr[32]; | |
2544 | int hdrlen; | |
2545 | int ret; | |
2546 | ||
2547 | if (has_loose_object(sha1)) | |
2548 | return 0; | |
2549 | buf = read_packed_sha1(sha1, &type, &len); | |
2550 | if (!buf) | |
2551 | return error("cannot read sha1_file for %s", sha1_to_hex(sha1)); | |
2552 | hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1; | |
2553 | ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime); | |
2554 | free(buf); | |
2555 | ||
2556 | return ret; | |
2557 | } | |
2558 | ||
2559 | int has_pack_index(const unsigned char *sha1) | |
2560 | { | |
2561 | struct stat st; | |
2562 | if (stat(sha1_pack_index_name(sha1), &st)) | |
2563 | return 0; | |
2564 | return 1; | |
2565 | } | |
2566 | ||
2567 | int has_sha1_pack(const unsigned char *sha1) | |
2568 | { | |
2569 | struct pack_entry e; | |
2570 | return find_pack_entry(sha1, &e); | |
2571 | } | |
2572 | ||
2573 | int has_sha1_file(const unsigned char *sha1) | |
2574 | { | |
2575 | struct pack_entry e; | |
2576 | ||
2577 | if (find_pack_entry(sha1, &e)) | |
2578 | return 1; | |
2579 | return has_loose_object(sha1); | |
2580 | } | |
2581 | ||
2582 | static void check_tree(const void *buf, size_t size) | |
2583 | { | |
2584 | struct tree_desc desc; | |
2585 | struct name_entry entry; | |
2586 | ||
2587 | init_tree_desc(&desc, buf, size); | |
2588 | while (tree_entry(&desc, &entry)) | |
2589 | /* do nothing | |
2590 | * tree_entry() will die() on malformed entries */ | |
2591 | ; | |
2592 | } | |
2593 | ||
2594 | static void check_commit(const void *buf, size_t size) | |
2595 | { | |
2596 | struct commit c; | |
2597 | memset(&c, 0, sizeof(c)); | |
2598 | if (parse_commit_buffer(&c, buf, size)) | |
2599 | die("corrupt commit"); | |
2600 | } | |
2601 | ||
2602 | static void check_tag(const void *buf, size_t size) | |
2603 | { | |
2604 | struct tag t; | |
2605 | memset(&t, 0, sizeof(t)); | |
2606 | if (parse_tag_buffer(&t, buf, size)) | |
2607 | die("corrupt tag"); | |
2608 | } | |
2609 | ||
2610 | static int index_mem(unsigned char *sha1, void *buf, size_t size, | |
2611 | enum object_type type, | |
2612 | const char *path, unsigned flags) | |
2613 | { | |
2614 | int ret, re_allocated = 0; | |
2615 | int write_object = flags & HASH_WRITE_OBJECT; | |
2616 | ||
2617 | if (!type) | |
2618 | type = OBJ_BLOB; | |
2619 | ||
2620 | /* | |
2621 | * Convert blobs to git internal format | |
2622 | */ | |
2623 | if ((type == OBJ_BLOB) && path) { | |
2624 | struct strbuf nbuf = STRBUF_INIT; | |
2625 | if (convert_to_git(path, buf, size, &nbuf, | |
2626 | write_object ? safe_crlf : 0)) { | |
2627 | buf = strbuf_detach(&nbuf, &size); | |
2628 | re_allocated = 1; | |
2629 | } | |
2630 | } | |
2631 | if (flags & HASH_FORMAT_CHECK) { | |
2632 | if (type == OBJ_TREE) | |
2633 | check_tree(buf, size); | |
2634 | if (type == OBJ_COMMIT) | |
2635 | check_commit(buf, size); | |
2636 | if (type == OBJ_TAG) | |
2637 | check_tag(buf, size); | |
2638 | } | |
2639 | ||
2640 | if (write_object) | |
2641 | ret = write_sha1_file(buf, size, typename(type), sha1); | |
2642 | else | |
2643 | ret = hash_sha1_file(buf, size, typename(type), sha1); | |
2644 | if (re_allocated) | |
2645 | free(buf); | |
2646 | return ret; | |
2647 | } | |
2648 | ||
2649 | static int index_pipe(unsigned char *sha1, int fd, enum object_type type, | |
2650 | const char *path, unsigned flags) | |
2651 | { | |
2652 | struct strbuf sbuf = STRBUF_INIT; | |
2653 | int ret; | |
2654 | ||
2655 | if (strbuf_read(&sbuf, fd, 4096) >= 0) | |
2656 | ret = index_mem(sha1, sbuf.buf, sbuf.len, type, path, flags); | |
2657 | else | |
2658 | ret = -1; | |
2659 | strbuf_release(&sbuf); | |
2660 | return ret; | |
2661 | } | |
2662 | ||
2663 | #define SMALL_FILE_SIZE (32*1024) | |
2664 | ||
2665 | static int index_core(unsigned char *sha1, int fd, size_t size, | |
2666 | enum object_type type, const char *path, | |
2667 | unsigned flags) | |
2668 | { | |
2669 | int ret; | |
2670 | ||
2671 | if (!size) { | |
2672 | ret = index_mem(sha1, NULL, size, type, path, flags); | |
2673 | } else if (size <= SMALL_FILE_SIZE) { | |
2674 | char *buf = xmalloc(size); | |
2675 | if (size == read_in_full(fd, buf, size)) | |
2676 | ret = index_mem(sha1, buf, size, type, path, flags); | |
2677 | else | |
2678 | ret = error("short read %s", strerror(errno)); | |
2679 | free(buf); | |
2680 | } else { | |
2681 | void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); | |
2682 | ret = index_mem(sha1, buf, size, type, path, flags); | |
2683 | munmap(buf, size); | |
2684 | } | |
2685 | return ret; | |
2686 | } | |
2687 | ||
2688 | /* | |
2689 | * This creates one packfile per large blob, because the caller | |
2690 | * immediately wants the result sha1, and fast-import can report the | |
2691 | * object name via marks mechanism only by closing the created | |
2692 | * packfile. | |
2693 | * | |
2694 | * This also bypasses the usual "convert-to-git" dance, and that is on | |
2695 | * purpose. We could write a streaming version of the converting | |
2696 | * functions and insert that before feeding the data to fast-import | |
2697 | * (or equivalent in-core API described above), but the primary | |
2698 | * motivation for trying to stream from the working tree file and to | |
2699 | * avoid mmaping it in core is to deal with large binary blobs, and | |
2700 | * by definition they do _not_ want to get any conversion. | |
2701 | */ | |
2702 | static int index_stream(unsigned char *sha1, int fd, size_t size, | |
2703 | enum object_type type, const char *path, | |
2704 | unsigned flags) | |
2705 | { | |
2706 | struct child_process fast_import; | |
2707 | char export_marks[512]; | |
2708 | const char *argv[] = { "fast-import", "--quiet", export_marks, NULL }; | |
2709 | char tmpfile[512]; | |
2710 | char fast_import_cmd[512]; | |
2711 | char buf[512]; | |
2712 | int len, tmpfd; | |
2713 | ||
2714 | strcpy(tmpfile, git_path("hashstream_XXXXXX")); | |
2715 | tmpfd = git_mkstemp_mode(tmpfile, 0600); | |
2716 | if (tmpfd < 0) | |
2717 | die_errno("cannot create tempfile: %s", tmpfile); | |
2718 | if (close(tmpfd)) | |
2719 | die_errno("cannot close tempfile: %s", tmpfile); | |
2720 | sprintf(export_marks, "--export-marks=%s", tmpfile); | |
2721 | ||
2722 | memset(&fast_import, 0, sizeof(fast_import)); | |
2723 | fast_import.in = -1; | |
2724 | fast_import.argv = argv; | |
2725 | fast_import.git_cmd = 1; | |
2726 | if (start_command(&fast_import)) | |
2727 | die_errno("index-stream: git fast-import failed"); | |
2728 | ||
2729 | len = sprintf(fast_import_cmd, "blob\nmark :1\ndata %lu\n", | |
2730 | (unsigned long) size); | |
2731 | write_or_whine(fast_import.in, fast_import_cmd, len, | |
2732 | "index-stream: feeding fast-import"); | |
2733 | while (size) { | |
2734 | char buf[10240]; | |
2735 | size_t sz = size < sizeof(buf) ? size : sizeof(buf); | |
2736 | size_t actual; | |
2737 | ||
2738 | actual = read_in_full(fd, buf, sz); | |
2739 | if (actual < 0) | |
2740 | die_errno("index-stream: reading input"); | |
2741 | if (write_in_full(fast_import.in, buf, actual) != actual) | |
2742 | die_errno("index-stream: feeding fast-import"); | |
2743 | size -= actual; | |
2744 | } | |
2745 | if (close(fast_import.in)) | |
2746 | die_errno("index-stream: closing fast-import"); | |
2747 | if (finish_command(&fast_import)) | |
2748 | die_errno("index-stream: finishing fast-import"); | |
2749 | ||
2750 | tmpfd = open(tmpfile, O_RDONLY); | |
2751 | if (tmpfd < 0) | |
2752 | die_errno("index-stream: cannot open fast-import mark"); | |
2753 | len = read(tmpfd, buf, sizeof(buf)); | |
2754 | if (len < 0) | |
2755 | die_errno("index-stream: reading fast-import mark"); | |
2756 | if (close(tmpfd) < 0) | |
2757 | die_errno("index-stream: closing fast-import mark"); | |
2758 | if (unlink(tmpfile)) | |
2759 | die_errno("index-stream: unlinking fast-import mark"); | |
2760 | if (len != 44 || | |
2761 | memcmp(":1 ", buf, 3) || | |
2762 | get_sha1_hex(buf + 3, sha1)) | |
2763 | die_errno("index-stream: unexpected fast-import mark: <%s>", buf); | |
2764 | return 0; | |
2765 | } | |
2766 | ||
2767 | int index_fd(unsigned char *sha1, int fd, struct stat *st, | |
2768 | enum object_type type, const char *path, unsigned flags) | |
2769 | { | |
2770 | int ret; | |
2771 | size_t size = xsize_t(st->st_size); | |
2772 | ||
2773 | if (!S_ISREG(st->st_mode)) | |
2774 | ret = index_pipe(sha1, fd, type, path, flags); | |
2775 | else if (size <= big_file_threshold || type != OBJ_BLOB) | |
2776 | ret = index_core(sha1, fd, size, type, path, flags); | |
2777 | else | |
2778 | ret = index_stream(sha1, fd, size, type, path, flags); | |
2779 | close(fd); | |
2780 | return ret; | |
2781 | } | |
2782 | ||
2783 | int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags) | |
2784 | { | |
2785 | int fd; | |
2786 | struct strbuf sb = STRBUF_INIT; | |
2787 | ||
2788 | switch (st->st_mode & S_IFMT) { | |
2789 | case S_IFREG: | |
2790 | fd = open(path, O_RDONLY); | |
2791 | if (fd < 0) | |
2792 | return error("open(\"%s\"): %s", path, | |
2793 | strerror(errno)); | |
2794 | if (index_fd(sha1, fd, st, OBJ_BLOB, path, flags) < 0) | |
2795 | return error("%s: failed to insert into database", | |
2796 | path); | |
2797 | break; | |
2798 | case S_IFLNK: | |
2799 | if (strbuf_readlink(&sb, path, st->st_size)) { | |
2800 | char *errstr = strerror(errno); | |
2801 | return error("readlink(\"%s\"): %s", path, | |
2802 | errstr); | |
2803 | } | |
2804 | if (!(flags & HASH_WRITE_OBJECT)) | |
2805 | hash_sha1_file(sb.buf, sb.len, blob_type, sha1); | |
2806 | else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1)) | |
2807 | return error("%s: failed to insert into database", | |
2808 | path); | |
2809 | strbuf_release(&sb); | |
2810 | break; | |
2811 | case S_IFDIR: | |
2812 | return resolve_gitlink_ref(path, "HEAD", sha1); | |
2813 | default: | |
2814 | return error("%s: unsupported file type", path); | |
2815 | } | |
2816 | return 0; | |
2817 | } | |
2818 | ||
2819 | int read_pack_header(int fd, struct pack_header *header) | |
2820 | { | |
2821 | if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header)) | |
2822 | /* "eof before pack header was fully read" */ | |
2823 | return PH_ERROR_EOF; | |
2824 | ||
2825 | if (header->hdr_signature != htonl(PACK_SIGNATURE)) | |
2826 | /* "protocol error (pack signature mismatch detected)" */ | |
2827 | return PH_ERROR_PACK_SIGNATURE; | |
2828 | if (!pack_version_ok(header->hdr_version)) | |
2829 | /* "protocol error (pack version unsupported)" */ | |
2830 | return PH_ERROR_PROTOCOL; | |
2831 | return 0; | |
2832 | } | |
2833 | ||
2834 | void assert_sha1_type(const unsigned char *sha1, enum object_type expect) | |
2835 | { | |
2836 | enum object_type type = sha1_object_info(sha1, NULL); | |
2837 | if (type < 0) | |
2838 | die("%s is not a valid object", sha1_to_hex(sha1)); | |
2839 | if (type != expect) | |
2840 | die("%s is not a valid '%s' object", sha1_to_hex(sha1), | |
2841 | typename(expect)); | |
2842 | } |