cache.h: allow oid_object_info to handle arbitrary repositories
[git/git.git] / sha1_file.c
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 "config.h"
11 #include "string-list.h"
12 #include "lockfile.h"
13 #include "delta.h"
14 #include "pack.h"
15 #include "blob.h"
16 #include "commit.h"
17 #include "run-command.h"
18 #include "tag.h"
19 #include "tree.h"
20 #include "tree-walk.h"
21 #include "refs.h"
22 #include "pack-revindex.h"
23 #include "sha1-lookup.h"
24 #include "bulk-checkin.h"
25 #include "repository.h"
26 #include "replace-object.h"
27 #include "streaming.h"
28 #include "dir.h"
29 #include "list.h"
30 #include "mergesort.h"
31 #include "quote.h"
32 #include "packfile.h"
33 #include "fetch-object.h"
34 #include "object-store.h"
35
36 /* The maximum size for an object header. */
37 #define MAX_HEADER_LEN 32
38
39 const unsigned char null_sha1[GIT_MAX_RAWSZ];
40 const struct object_id null_oid;
41 const struct object_id empty_tree_oid = {
42 EMPTY_TREE_SHA1_BIN_LITERAL
43 };
44 const struct object_id empty_blob_oid = {
45 EMPTY_BLOB_SHA1_BIN_LITERAL
46 };
47
48 static void git_hash_sha1_init(git_hash_ctx *ctx)
49 {
50 git_SHA1_Init(&ctx->sha1);
51 }
52
53 static void git_hash_sha1_update(git_hash_ctx *ctx, const void *data, size_t len)
54 {
55 git_SHA1_Update(&ctx->sha1, data, len);
56 }
57
58 static void git_hash_sha1_final(unsigned char *hash, git_hash_ctx *ctx)
59 {
60 git_SHA1_Final(hash, &ctx->sha1);
61 }
62
63 static void git_hash_unknown_init(git_hash_ctx *ctx)
64 {
65 die("trying to init unknown hash");
66 }
67
68 static void git_hash_unknown_update(git_hash_ctx *ctx, const void *data, size_t len)
69 {
70 die("trying to update unknown hash");
71 }
72
73 static void git_hash_unknown_final(unsigned char *hash, git_hash_ctx *ctx)
74 {
75 die("trying to finalize unknown hash");
76 }
77
78 const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
79 {
80 NULL,
81 0x00000000,
82 0,
83 0,
84 git_hash_unknown_init,
85 git_hash_unknown_update,
86 git_hash_unknown_final,
87 NULL,
88 NULL,
89 },
90 {
91 "sha-1",
92 /* "sha1", big-endian */
93 0x73686131,
94 GIT_SHA1_RAWSZ,
95 GIT_SHA1_HEXSZ,
96 git_hash_sha1_init,
97 git_hash_sha1_update,
98 git_hash_sha1_final,
99 &empty_tree_oid,
100 &empty_blob_oid,
101 },
102 };
103
104 /*
105 * This is meant to hold a *small* number of objects that you would
106 * want read_sha1_file() to be able to return, but yet you do not want
107 * to write them into the object store (e.g. a browse-only
108 * application).
109 */
110 static struct cached_object {
111 unsigned char sha1[20];
112 enum object_type type;
113 void *buf;
114 unsigned long size;
115 } *cached_objects;
116 static int cached_object_nr, cached_object_alloc;
117
118 static struct cached_object empty_tree = {
119 EMPTY_TREE_SHA1_BIN_LITERAL,
120 OBJ_TREE,
121 "",
122 0
123 };
124
125 static struct cached_object *find_cached_object(const unsigned char *sha1)
126 {
127 int i;
128 struct cached_object *co = cached_objects;
129
130 for (i = 0; i < cached_object_nr; i++, co++) {
131 if (!hashcmp(co->sha1, sha1))
132 return co;
133 }
134 if (!hashcmp(sha1, empty_tree.sha1))
135 return &empty_tree;
136 return NULL;
137 }
138
139
140 static int get_conv_flags(unsigned flags)
141 {
142 if (flags & HASH_RENORMALIZE)
143 return CONV_EOL_RENORMALIZE;
144 else if (flags & HASH_WRITE_OBJECT)
145 return global_conv_flags_eol;
146 else
147 return 0;
148 }
149
150
151 int mkdir_in_gitdir(const char *path)
152 {
153 if (mkdir(path, 0777)) {
154 int saved_errno = errno;
155 struct stat st;
156 struct strbuf sb = STRBUF_INIT;
157
158 if (errno != EEXIST)
159 return -1;
160 /*
161 * Are we looking at a path in a symlinked worktree
162 * whose original repository does not yet have it?
163 * e.g. .git/rr-cache pointing at its original
164 * repository in which the user hasn't performed any
165 * conflict resolution yet?
166 */
167 if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
168 strbuf_readlink(&sb, path, st.st_size) ||
169 !is_absolute_path(sb.buf) ||
170 mkdir(sb.buf, 0777)) {
171 strbuf_release(&sb);
172 errno = saved_errno;
173 return -1;
174 }
175 strbuf_release(&sb);
176 }
177 return adjust_shared_perm(path);
178 }
179
180 enum scld_error safe_create_leading_directories(char *path)
181 {
182 char *next_component = path + offset_1st_component(path);
183 enum scld_error ret = SCLD_OK;
184
185 while (ret == SCLD_OK && next_component) {
186 struct stat st;
187 char *slash = next_component, slash_character;
188
189 while (*slash && !is_dir_sep(*slash))
190 slash++;
191
192 if (!*slash)
193 break;
194
195 next_component = slash + 1;
196 while (is_dir_sep(*next_component))
197 next_component++;
198 if (!*next_component)
199 break;
200
201 slash_character = *slash;
202 *slash = '\0';
203 if (!stat(path, &st)) {
204 /* path exists */
205 if (!S_ISDIR(st.st_mode)) {
206 errno = ENOTDIR;
207 ret = SCLD_EXISTS;
208 }
209 } else if (mkdir(path, 0777)) {
210 if (errno == EEXIST &&
211 !stat(path, &st) && S_ISDIR(st.st_mode))
212 ; /* somebody created it since we checked */
213 else if (errno == ENOENT)
214 /*
215 * Either mkdir() failed because
216 * somebody just pruned the containing
217 * directory, or stat() failed because
218 * the file that was in our way was
219 * just removed. Either way, inform
220 * the caller that it might be worth
221 * trying again:
222 */
223 ret = SCLD_VANISHED;
224 else
225 ret = SCLD_FAILED;
226 } else if (adjust_shared_perm(path)) {
227 ret = SCLD_PERMS;
228 }
229 *slash = slash_character;
230 }
231 return ret;
232 }
233
234 enum scld_error safe_create_leading_directories_const(const char *path)
235 {
236 int save_errno;
237 /* path points to cache entries, so xstrdup before messing with it */
238 char *buf = xstrdup(path);
239 enum scld_error result = safe_create_leading_directories(buf);
240
241 save_errno = errno;
242 free(buf);
243 errno = save_errno;
244 return result;
245 }
246
247 int raceproof_create_file(const char *path, create_file_fn fn, void *cb)
248 {
249 /*
250 * The number of times we will try to remove empty directories
251 * in the way of path. This is only 1 because if another
252 * process is racily creating directories that conflict with
253 * us, we don't want to fight against them.
254 */
255 int remove_directories_remaining = 1;
256
257 /*
258 * The number of times that we will try to create the
259 * directories containing path. We are willing to attempt this
260 * more than once, because another process could be trying to
261 * clean up empty directories at the same time as we are
262 * trying to create them.
263 */
264 int create_directories_remaining = 3;
265
266 /* A scratch copy of path, filled lazily if we need it: */
267 struct strbuf path_copy = STRBUF_INIT;
268
269 int ret, save_errno;
270
271 /* Sanity check: */
272 assert(*path);
273
274 retry_fn:
275 ret = fn(path, cb);
276 save_errno = errno;
277 if (!ret)
278 goto out;
279
280 if (errno == EISDIR && remove_directories_remaining-- > 0) {
281 /*
282 * A directory is in the way. Maybe it is empty; try
283 * to remove it:
284 */
285 if (!path_copy.len)
286 strbuf_addstr(&path_copy, path);
287
288 if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY))
289 goto retry_fn;
290 } else if (errno == ENOENT && create_directories_remaining-- > 0) {
291 /*
292 * Maybe the containing directory didn't exist, or
293 * maybe it was just deleted by a process that is
294 * racing with us to clean up empty directories. Try
295 * to create it:
296 */
297 enum scld_error scld_result;
298
299 if (!path_copy.len)
300 strbuf_addstr(&path_copy, path);
301
302 do {
303 scld_result = safe_create_leading_directories(path_copy.buf);
304 if (scld_result == SCLD_OK)
305 goto retry_fn;
306 } while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0);
307 }
308
309 out:
310 strbuf_release(&path_copy);
311 errno = save_errno;
312 return ret;
313 }
314
315 static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1)
316 {
317 int i;
318 for (i = 0; i < 20; i++) {
319 static char hex[] = "0123456789abcdef";
320 unsigned int val = sha1[i];
321 strbuf_addch(buf, hex[val >> 4]);
322 strbuf_addch(buf, hex[val & 0xf]);
323 if (!i)
324 strbuf_addch(buf, '/');
325 }
326 }
327
328 void sha1_file_name(struct repository *r, struct strbuf *buf, const unsigned char *sha1)
329 {
330 strbuf_addstr(buf, r->objects->objectdir);
331 strbuf_addch(buf, '/');
332 fill_sha1_path(buf, sha1);
333 }
334
335 struct strbuf *alt_scratch_buf(struct alternate_object_database *alt)
336 {
337 strbuf_setlen(&alt->scratch, alt->base_len);
338 return &alt->scratch;
339 }
340
341 static const char *alt_sha1_path(struct alternate_object_database *alt,
342 const unsigned char *sha1)
343 {
344 struct strbuf *buf = alt_scratch_buf(alt);
345 fill_sha1_path(buf, sha1);
346 return buf->buf;
347 }
348
349 /*
350 * Return non-zero iff the path is usable as an alternate object database.
351 */
352 static int alt_odb_usable(struct raw_object_store *o,
353 struct strbuf *path,
354 const char *normalized_objdir)
355 {
356 struct alternate_object_database *alt;
357
358 /* Detect cases where alternate disappeared */
359 if (!is_directory(path->buf)) {
360 error("object directory %s does not exist; "
361 "check .git/objects/info/alternates.",
362 path->buf);
363 return 0;
364 }
365
366 /*
367 * Prevent the common mistake of listing the same
368 * thing twice, or object directory itself.
369 */
370 for (alt = o->alt_odb_list; alt; alt = alt->next) {
371 if (!fspathcmp(path->buf, alt->path))
372 return 0;
373 }
374 if (!fspathcmp(path->buf, normalized_objdir))
375 return 0;
376
377 return 1;
378 }
379
380 /*
381 * Prepare alternate object database registry.
382 *
383 * The variable alt_odb_list points at the list of struct
384 * alternate_object_database. The elements on this list come from
385 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
386 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
387 * whose contents is similar to that environment variable but can be
388 * LF separated. Its base points at a statically allocated buffer that
389 * contains "/the/directory/corresponding/to/.git/objects/...", while
390 * its name points just after the slash at the end of ".git/objects/"
391 * in the example above, and has enough space to hold 40-byte hex
392 * SHA1, an extra slash for the first level indirection, and the
393 * terminating NUL.
394 */
395 static void read_info_alternates(struct repository *r,
396 const char *relative_base,
397 int depth);
398 static int link_alt_odb_entry(struct repository *r, const char *entry,
399 const char *relative_base, int depth, const char *normalized_objdir)
400 {
401 struct alternate_object_database *ent;
402 struct strbuf pathbuf = STRBUF_INIT;
403
404 if (!is_absolute_path(entry) && relative_base) {
405 strbuf_realpath(&pathbuf, relative_base, 1);
406 strbuf_addch(&pathbuf, '/');
407 }
408 strbuf_addstr(&pathbuf, entry);
409
410 if (strbuf_normalize_path(&pathbuf) < 0 && relative_base) {
411 error("unable to normalize alternate object path: %s",
412 pathbuf.buf);
413 strbuf_release(&pathbuf);
414 return -1;
415 }
416
417 /*
418 * The trailing slash after the directory name is given by
419 * this function at the end. Remove duplicates.
420 */
421 while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
422 strbuf_setlen(&pathbuf, pathbuf.len - 1);
423
424 if (!alt_odb_usable(r->objects, &pathbuf, normalized_objdir)) {
425 strbuf_release(&pathbuf);
426 return -1;
427 }
428
429 ent = alloc_alt_odb(pathbuf.buf);
430
431 /* add the alternate entry */
432 *r->objects->alt_odb_tail = ent;
433 r->objects->alt_odb_tail = &(ent->next);
434 ent->next = NULL;
435
436 /* recursively add alternates */
437 read_info_alternates(r, pathbuf.buf, depth + 1);
438
439 strbuf_release(&pathbuf);
440 return 0;
441 }
442
443 static const char *parse_alt_odb_entry(const char *string,
444 int sep,
445 struct strbuf *out)
446 {
447 const char *end;
448
449 strbuf_reset(out);
450
451 if (*string == '#') {
452 /* comment; consume up to next separator */
453 end = strchrnul(string, sep);
454 } else if (*string == '"' && !unquote_c_style(out, string, &end)) {
455 /*
456 * quoted path; unquote_c_style has copied the
457 * data for us and set "end". Broken quoting (e.g.,
458 * an entry that doesn't end with a quote) falls
459 * back to the unquoted case below.
460 */
461 } else {
462 /* normal, unquoted path */
463 end = strchrnul(string, sep);
464 strbuf_add(out, string, end - string);
465 }
466
467 if (*end)
468 end++;
469 return end;
470 }
471
472 static void link_alt_odb_entries(struct repository *r, const char *alt,
473 int sep, const char *relative_base, int depth)
474 {
475 struct strbuf objdirbuf = STRBUF_INIT;
476 struct strbuf entry = STRBUF_INIT;
477
478 if (!alt || !*alt)
479 return;
480
481 if (depth > 5) {
482 error("%s: ignoring alternate object stores, nesting too deep.",
483 relative_base);
484 return;
485 }
486
487 strbuf_add_absolute_path(&objdirbuf, r->objects->objectdir);
488 if (strbuf_normalize_path(&objdirbuf) < 0)
489 die("unable to normalize object directory: %s",
490 objdirbuf.buf);
491
492 while (*alt) {
493 alt = parse_alt_odb_entry(alt, sep, &entry);
494 if (!entry.len)
495 continue;
496 link_alt_odb_entry(r, entry.buf,
497 relative_base, depth, objdirbuf.buf);
498 }
499 strbuf_release(&entry);
500 strbuf_release(&objdirbuf);
501 }
502
503 static void read_info_alternates(struct repository *r,
504 const char *relative_base,
505 int depth)
506 {
507 char *path;
508 struct strbuf buf = STRBUF_INIT;
509
510 path = xstrfmt("%s/info/alternates", relative_base);
511 if (strbuf_read_file(&buf, path, 1024) < 0) {
512 warn_on_fopen_errors(path);
513 free(path);
514 return;
515 }
516
517 link_alt_odb_entries(r, buf.buf, '\n', relative_base, depth);
518 strbuf_release(&buf);
519 free(path);
520 }
521
522 struct alternate_object_database *alloc_alt_odb(const char *dir)
523 {
524 struct alternate_object_database *ent;
525
526 FLEX_ALLOC_STR(ent, path, dir);
527 strbuf_init(&ent->scratch, 0);
528 strbuf_addf(&ent->scratch, "%s/", dir);
529 ent->base_len = ent->scratch.len;
530
531 return ent;
532 }
533
534 void add_to_alternates_file(const char *reference)
535 {
536 struct lock_file lock = LOCK_INIT;
537 char *alts = git_pathdup("objects/info/alternates");
538 FILE *in, *out;
539 int found = 0;
540
541 hold_lock_file_for_update(&lock, alts, LOCK_DIE_ON_ERROR);
542 out = fdopen_lock_file(&lock, "w");
543 if (!out)
544 die_errno("unable to fdopen alternates lockfile");
545
546 in = fopen(alts, "r");
547 if (in) {
548 struct strbuf line = STRBUF_INIT;
549
550 while (strbuf_getline(&line, in) != EOF) {
551 if (!strcmp(reference, line.buf)) {
552 found = 1;
553 break;
554 }
555 fprintf_or_die(out, "%s\n", line.buf);
556 }
557
558 strbuf_release(&line);
559 fclose(in);
560 }
561 else if (errno != ENOENT)
562 die_errno("unable to read alternates file");
563
564 if (found) {
565 rollback_lock_file(&lock);
566 } else {
567 fprintf_or_die(out, "%s\n", reference);
568 if (commit_lock_file(&lock))
569 die_errno("unable to move new alternates file into place");
570 if (the_repository->objects->alt_odb_tail)
571 link_alt_odb_entries(the_repository, reference,
572 '\n', NULL, 0);
573 }
574 free(alts);
575 }
576
577 void add_to_alternates_memory(const char *reference)
578 {
579 /*
580 * Make sure alternates are initialized, or else our entry may be
581 * overwritten when they are.
582 */
583 prepare_alt_odb(the_repository);
584
585 link_alt_odb_entries(the_repository, reference,
586 '\n', NULL, 0);
587 }
588
589 /*
590 * Compute the exact path an alternate is at and returns it. In case of
591 * error NULL is returned and the human readable error is added to `err`
592 * `path` may be relative and should point to $GITDIR.
593 * `err` must not be null.
594 */
595 char *compute_alternate_path(const char *path, struct strbuf *err)
596 {
597 char *ref_git = NULL;
598 const char *repo, *ref_git_s;
599 int seen_error = 0;
600
601 ref_git_s = real_path_if_valid(path);
602 if (!ref_git_s) {
603 seen_error = 1;
604 strbuf_addf(err, _("path '%s' does not exist"), path);
605 goto out;
606 } else
607 /*
608 * Beware: read_gitfile(), real_path() and mkpath()
609 * return static buffer
610 */
611 ref_git = xstrdup(ref_git_s);
612
613 repo = read_gitfile(ref_git);
614 if (!repo)
615 repo = read_gitfile(mkpath("%s/.git", ref_git));
616 if (repo) {
617 free(ref_git);
618 ref_git = xstrdup(repo);
619 }
620
621 if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
622 char *ref_git_git = mkpathdup("%s/.git", ref_git);
623 free(ref_git);
624 ref_git = ref_git_git;
625 } else if (!is_directory(mkpath("%s/objects", ref_git))) {
626 struct strbuf sb = STRBUF_INIT;
627 seen_error = 1;
628 if (get_common_dir(&sb, ref_git)) {
629 strbuf_addf(err,
630 _("reference repository '%s' as a linked "
631 "checkout is not supported yet."),
632 path);
633 goto out;
634 }
635
636 strbuf_addf(err, _("reference repository '%s' is not a "
637 "local repository."), path);
638 goto out;
639 }
640
641 if (!access(mkpath("%s/shallow", ref_git), F_OK)) {
642 strbuf_addf(err, _("reference repository '%s' is shallow"),
643 path);
644 seen_error = 1;
645 goto out;
646 }
647
648 if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) {
649 strbuf_addf(err,
650 _("reference repository '%s' is grafted"),
651 path);
652 seen_error = 1;
653 goto out;
654 }
655
656 out:
657 if (seen_error) {
658 FREE_AND_NULL(ref_git);
659 }
660
661 return ref_git;
662 }
663
664 int foreach_alt_odb(alt_odb_fn fn, void *cb)
665 {
666 struct alternate_object_database *ent;
667 int r = 0;
668
669 prepare_alt_odb(the_repository);
670 for (ent = the_repository->objects->alt_odb_list; ent; ent = ent->next) {
671 r = fn(ent, cb);
672 if (r)
673 break;
674 }
675 return r;
676 }
677
678 void prepare_alt_odb(struct repository *r)
679 {
680 if (r->objects->alt_odb_tail)
681 return;
682
683 r->objects->alt_odb_tail = &r->objects->alt_odb_list;
684 link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0);
685
686 read_info_alternates(r, r->objects->objectdir, 0);
687 }
688
689 /* Returns 1 if we have successfully freshened the file, 0 otherwise. */
690 static int freshen_file(const char *fn)
691 {
692 struct utimbuf t;
693 t.actime = t.modtime = time(NULL);
694 return !utime(fn, &t);
695 }
696
697 /*
698 * All of the check_and_freshen functions return 1 if the file exists and was
699 * freshened (if freshening was requested), 0 otherwise. If they return
700 * 0, you should not assume that it is safe to skip a write of the object (it
701 * either does not exist on disk, or has a stale mtime and may be subject to
702 * pruning).
703 */
704 int check_and_freshen_file(const char *fn, int freshen)
705 {
706 if (access(fn, F_OK))
707 return 0;
708 if (freshen && !freshen_file(fn))
709 return 0;
710 return 1;
711 }
712
713 static int check_and_freshen_local(const unsigned char *sha1, int freshen)
714 {
715 static struct strbuf buf = STRBUF_INIT;
716
717 strbuf_reset(&buf);
718 sha1_file_name(the_repository, &buf, sha1);
719
720 return check_and_freshen_file(buf.buf, freshen);
721 }
722
723 static int check_and_freshen_nonlocal(const unsigned char *sha1, int freshen)
724 {
725 struct alternate_object_database *alt;
726 prepare_alt_odb(the_repository);
727 for (alt = the_repository->objects->alt_odb_list; alt; alt = alt->next) {
728 const char *path = alt_sha1_path(alt, sha1);
729 if (check_and_freshen_file(path, freshen))
730 return 1;
731 }
732 return 0;
733 }
734
735 static int check_and_freshen(const unsigned char *sha1, int freshen)
736 {
737 return check_and_freshen_local(sha1, freshen) ||
738 check_and_freshen_nonlocal(sha1, freshen);
739 }
740
741 int has_loose_object_nonlocal(const unsigned char *sha1)
742 {
743 return check_and_freshen_nonlocal(sha1, 0);
744 }
745
746 static int has_loose_object(const unsigned char *sha1)
747 {
748 return check_and_freshen(sha1, 0);
749 }
750
751 static void mmap_limit_check(size_t length)
752 {
753 static size_t limit = 0;
754 if (!limit) {
755 limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
756 if (!limit)
757 limit = SIZE_MAX;
758 }
759 if (length > limit)
760 die("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX,
761 (uintmax_t)length, (uintmax_t)limit);
762 }
763
764 void *xmmap_gently(void *start, size_t length,
765 int prot, int flags, int fd, off_t offset)
766 {
767 void *ret;
768
769 mmap_limit_check(length);
770 ret = mmap(start, length, prot, flags, fd, offset);
771 if (ret == MAP_FAILED) {
772 if (!length)
773 return NULL;
774 release_pack_memory(length);
775 ret = mmap(start, length, prot, flags, fd, offset);
776 }
777 return ret;
778 }
779
780 void *xmmap(void *start, size_t length,
781 int prot, int flags, int fd, off_t offset)
782 {
783 void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
784 if (ret == MAP_FAILED)
785 die_errno("mmap failed");
786 return ret;
787 }
788
789 /*
790 * With an in-core object data in "map", rehash it to make sure the
791 * object name actually matches "sha1" to detect object corruption.
792 * With "map" == NULL, try reading the object named with "sha1" using
793 * the streaming interface and rehash it to do the same.
794 */
795 int check_object_signature(const struct object_id *oid, void *map,
796 unsigned long size, const char *type)
797 {
798 struct object_id real_oid;
799 enum object_type obj_type;
800 struct git_istream *st;
801 git_hash_ctx c;
802 char hdr[MAX_HEADER_LEN];
803 int hdrlen;
804
805 if (map) {
806 hash_object_file(map, size, type, &real_oid);
807 return oidcmp(oid, &real_oid) ? -1 : 0;
808 }
809
810 st = open_istream(oid, &obj_type, &size, NULL);
811 if (!st)
812 return -1;
813
814 /* Generate the header */
815 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", type_name(obj_type), size) + 1;
816
817 /* Sha1.. */
818 the_hash_algo->init_fn(&c);
819 the_hash_algo->update_fn(&c, hdr, hdrlen);
820 for (;;) {
821 char buf[1024 * 16];
822 ssize_t readlen = read_istream(st, buf, sizeof(buf));
823
824 if (readlen < 0) {
825 close_istream(st);
826 return -1;
827 }
828 if (!readlen)
829 break;
830 the_hash_algo->update_fn(&c, buf, readlen);
831 }
832 the_hash_algo->final_fn(real_oid.hash, &c);
833 close_istream(st);
834 return oidcmp(oid, &real_oid) ? -1 : 0;
835 }
836
837 int git_open_cloexec(const char *name, int flags)
838 {
839 int fd;
840 static int o_cloexec = O_CLOEXEC;
841
842 fd = open(name, flags | o_cloexec);
843 if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
844 /* Try again w/o O_CLOEXEC: the kernel might not support it */
845 o_cloexec &= ~O_CLOEXEC;
846 fd = open(name, flags | o_cloexec);
847 }
848
849 #if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
850 {
851 static int fd_cloexec = FD_CLOEXEC;
852
853 if (!o_cloexec && 0 <= fd && fd_cloexec) {
854 /* Opened w/o O_CLOEXEC? try with fcntl(2) to add it */
855 int flags = fcntl(fd, F_GETFD);
856 if (fcntl(fd, F_SETFD, flags | fd_cloexec))
857 fd_cloexec = 0;
858 }
859 }
860 #endif
861 return fd;
862 }
863
864 /*
865 * Find "sha1" as a loose object in the local repository or in an alternate.
866 * Returns 0 on success, negative on failure.
867 *
868 * The "path" out-parameter will give the path of the object we found (if any).
869 * Note that it may point to static storage and is only valid until another
870 * call to sha1_file_name(), etc.
871 */
872 static int stat_sha1_file(struct repository *r, const unsigned char *sha1,
873 struct stat *st, const char **path)
874 {
875 struct alternate_object_database *alt;
876 static struct strbuf buf = STRBUF_INIT;
877
878 strbuf_reset(&buf);
879 sha1_file_name(r, &buf, sha1);
880 *path = buf.buf;
881
882 if (!lstat(*path, st))
883 return 0;
884
885 prepare_alt_odb(r);
886 errno = ENOENT;
887 for (alt = r->objects->alt_odb_list; alt; alt = alt->next) {
888 *path = alt_sha1_path(alt, sha1);
889 if (!lstat(*path, st))
890 return 0;
891 }
892
893 return -1;
894 }
895
896 /*
897 * Like stat_sha1_file(), but actually open the object and return the
898 * descriptor. See the caveats on the "path" parameter above.
899 */
900 static int open_sha1_file(struct repository *r,
901 const unsigned char *sha1, const char **path)
902 {
903 int fd;
904 struct alternate_object_database *alt;
905 int most_interesting_errno;
906 static struct strbuf buf = STRBUF_INIT;
907
908 strbuf_reset(&buf);
909 sha1_file_name(r, &buf, sha1);
910 *path = buf.buf;
911
912 fd = git_open(*path);
913 if (fd >= 0)
914 return fd;
915 most_interesting_errno = errno;
916
917 prepare_alt_odb(r);
918 for (alt = r->objects->alt_odb_list; alt; alt = alt->next) {
919 *path = alt_sha1_path(alt, sha1);
920 fd = git_open(*path);
921 if (fd >= 0)
922 return fd;
923 if (most_interesting_errno == ENOENT)
924 most_interesting_errno = errno;
925 }
926 errno = most_interesting_errno;
927 return -1;
928 }
929
930 /*
931 * Map the loose object at "path" if it is not NULL, or the path found by
932 * searching for a loose object named "sha1".
933 */
934 static void *map_sha1_file_1(struct repository *r, const char *path,
935 const unsigned char *sha1, unsigned long *size)
936 {
937 void *map;
938 int fd;
939
940 if (path)
941 fd = git_open(path);
942 else
943 fd = open_sha1_file(r, sha1, &path);
944 map = NULL;
945 if (fd >= 0) {
946 struct stat st;
947
948 if (!fstat(fd, &st)) {
949 *size = xsize_t(st.st_size);
950 if (!*size) {
951 /* mmap() is forbidden on empty files */
952 error("object file %s is empty", path);
953 return NULL;
954 }
955 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
956 }
957 close(fd);
958 }
959 return map;
960 }
961
962 void *map_sha1_file(struct repository *r,
963 const unsigned char *sha1, unsigned long *size)
964 {
965 return map_sha1_file_1(r, NULL, sha1, size);
966 }
967
968 static int unpack_sha1_short_header(git_zstream *stream,
969 unsigned char *map, unsigned long mapsize,
970 void *buffer, unsigned long bufsiz)
971 {
972 /* Get the data stream */
973 memset(stream, 0, sizeof(*stream));
974 stream->next_in = map;
975 stream->avail_in = mapsize;
976 stream->next_out = buffer;
977 stream->avail_out = bufsiz;
978
979 git_inflate_init(stream);
980 return git_inflate(stream, 0);
981 }
982
983 int unpack_sha1_header(git_zstream *stream,
984 unsigned char *map, unsigned long mapsize,
985 void *buffer, unsigned long bufsiz)
986 {
987 int status = unpack_sha1_short_header(stream, map, mapsize,
988 buffer, bufsiz);
989
990 if (status < Z_OK)
991 return status;
992
993 /* Make sure we have the terminating NUL */
994 if (!memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
995 return -1;
996 return 0;
997 }
998
999 static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map,
1000 unsigned long mapsize, void *buffer,
1001 unsigned long bufsiz, struct strbuf *header)
1002 {
1003 int status;
1004
1005 status = unpack_sha1_short_header(stream, map, mapsize, buffer, bufsiz);
1006 if (status < Z_OK)
1007 return -1;
1008
1009 /*
1010 * Check if entire header is unpacked in the first iteration.
1011 */
1012 if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
1013 return 0;
1014
1015 /*
1016 * buffer[0..bufsiz] was not large enough. Copy the partial
1017 * result out to header, and then append the result of further
1018 * reading the stream.
1019 */
1020 strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
1021 stream->next_out = buffer;
1022 stream->avail_out = bufsiz;
1023
1024 do {
1025 status = git_inflate(stream, 0);
1026 strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
1027 if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
1028 return 0;
1029 stream->next_out = buffer;
1030 stream->avail_out = bufsiz;
1031 } while (status != Z_STREAM_END);
1032 return -1;
1033 }
1034
1035 static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
1036 {
1037 int bytes = strlen(buffer) + 1;
1038 unsigned char *buf = xmallocz(size);
1039 unsigned long n;
1040 int status = Z_OK;
1041
1042 n = stream->total_out - bytes;
1043 if (n > size)
1044 n = size;
1045 memcpy(buf, (char *) buffer + bytes, n);
1046 bytes = n;
1047 if (bytes <= size) {
1048 /*
1049 * The above condition must be (bytes <= size), not
1050 * (bytes < size). In other words, even though we
1051 * expect no more output and set avail_out to zero,
1052 * the input zlib stream may have bytes that express
1053 * "this concludes the stream", and we *do* want to
1054 * eat that input.
1055 *
1056 * Otherwise we would not be able to test that we
1057 * consumed all the input to reach the expected size;
1058 * we also want to check that zlib tells us that all
1059 * went well with status == Z_STREAM_END at the end.
1060 */
1061 stream->next_out = buf + bytes;
1062 stream->avail_out = size - bytes;
1063 while (status == Z_OK)
1064 status = git_inflate(stream, Z_FINISH);
1065 }
1066 if (status == Z_STREAM_END && !stream->avail_in) {
1067 git_inflate_end(stream);
1068 return buf;
1069 }
1070
1071 if (status < 0)
1072 error("corrupt loose object '%s'", sha1_to_hex(sha1));
1073 else if (stream->avail_in)
1074 error("garbage at end of loose object '%s'",
1075 sha1_to_hex(sha1));
1076 free(buf);
1077 return NULL;
1078 }
1079
1080 /*
1081 * We used to just use "sscanf()", but that's actually way
1082 * too permissive for what we want to check. So do an anal
1083 * object header parse by hand.
1084 */
1085 static int parse_sha1_header_extended(const char *hdr, struct object_info *oi,
1086 unsigned int flags)
1087 {
1088 const char *type_buf = hdr;
1089 unsigned long size;
1090 int type, type_len = 0;
1091
1092 /*
1093 * The type can be of any size but is followed by
1094 * a space.
1095 */
1096 for (;;) {
1097 char c = *hdr++;
1098 if (!c)
1099 return -1;
1100 if (c == ' ')
1101 break;
1102 type_len++;
1103 }
1104
1105 type = type_from_string_gently(type_buf, type_len, 1);
1106 if (oi->type_name)
1107 strbuf_add(oi->type_name, type_buf, type_len);
1108 /*
1109 * Set type to 0 if its an unknown object and
1110 * we're obtaining the type using '--allow-unknown-type'
1111 * option.
1112 */
1113 if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE) && (type < 0))
1114 type = 0;
1115 else if (type < 0)
1116 die("invalid object type");
1117 if (oi->typep)
1118 *oi->typep = type;
1119
1120 /*
1121 * The length must follow immediately, and be in canonical
1122 * decimal format (ie "010" is not valid).
1123 */
1124 size = *hdr++ - '0';
1125 if (size > 9)
1126 return -1;
1127 if (size) {
1128 for (;;) {
1129 unsigned long c = *hdr - '0';
1130 if (c > 9)
1131 break;
1132 hdr++;
1133 size = size * 10 + c;
1134 }
1135 }
1136
1137 if (oi->sizep)
1138 *oi->sizep = size;
1139
1140 /*
1141 * The length must be followed by a zero byte
1142 */
1143 return *hdr ? -1 : type;
1144 }
1145
1146 int parse_sha1_header(const char *hdr, unsigned long *sizep)
1147 {
1148 struct object_info oi = OBJECT_INFO_INIT;
1149
1150 oi.sizep = sizep;
1151 return parse_sha1_header_extended(hdr, &oi, 0);
1152 }
1153
1154 static int sha1_loose_object_info(struct repository *r,
1155 const unsigned char *sha1,
1156 struct object_info *oi, int flags)
1157 {
1158 int status = 0;
1159 unsigned long mapsize;
1160 void *map;
1161 git_zstream stream;
1162 char hdr[MAX_HEADER_LEN];
1163 struct strbuf hdrbuf = STRBUF_INIT;
1164 unsigned long size_scratch;
1165
1166 if (oi->delta_base_sha1)
1167 hashclr(oi->delta_base_sha1);
1168
1169 /*
1170 * If we don't care about type or size, then we don't
1171 * need to look inside the object at all. Note that we
1172 * do not optimize out the stat call, even if the
1173 * caller doesn't care about the disk-size, since our
1174 * return value implicitly indicates whether the
1175 * object even exists.
1176 */
1177 if (!oi->typep && !oi->type_name && !oi->sizep && !oi->contentp) {
1178 const char *path;
1179 struct stat st;
1180 if (stat_sha1_file(r, sha1, &st, &path) < 0)
1181 return -1;
1182 if (oi->disk_sizep)
1183 *oi->disk_sizep = st.st_size;
1184 return 0;
1185 }
1186
1187 map = map_sha1_file(r, sha1, &mapsize);
1188 if (!map)
1189 return -1;
1190
1191 if (!oi->sizep)
1192 oi->sizep = &size_scratch;
1193
1194 if (oi->disk_sizep)
1195 *oi->disk_sizep = mapsize;
1196 if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE)) {
1197 if (unpack_sha1_header_to_strbuf(&stream, map, mapsize, hdr, sizeof(hdr), &hdrbuf) < 0)
1198 status = error("unable to unpack %s header with --allow-unknown-type",
1199 sha1_to_hex(sha1));
1200 } else if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1201 status = error("unable to unpack %s header",
1202 sha1_to_hex(sha1));
1203 if (status < 0)
1204 ; /* Do nothing */
1205 else if (hdrbuf.len) {
1206 if ((status = parse_sha1_header_extended(hdrbuf.buf, oi, flags)) < 0)
1207 status = error("unable to parse %s header with --allow-unknown-type",
1208 sha1_to_hex(sha1));
1209 } else if ((status = parse_sha1_header_extended(hdr, oi, flags)) < 0)
1210 status = error("unable to parse %s header", sha1_to_hex(sha1));
1211
1212 if (status >= 0 && oi->contentp) {
1213 *oi->contentp = unpack_sha1_rest(&stream, hdr,
1214 *oi->sizep, sha1);
1215 if (!*oi->contentp) {
1216 git_inflate_end(&stream);
1217 status = -1;
1218 }
1219 } else
1220 git_inflate_end(&stream);
1221
1222 munmap(map, mapsize);
1223 if (status && oi->typep)
1224 *oi->typep = status;
1225 if (oi->sizep == &size_scratch)
1226 oi->sizep = NULL;
1227 strbuf_release(&hdrbuf);
1228 oi->whence = OI_LOOSE;
1229 return (status < 0) ? status : 0;
1230 }
1231
1232 int fetch_if_missing = 1;
1233
1234 int oid_object_info_extended(struct repository *r, const struct object_id *oid,
1235 struct object_info *oi, unsigned flags)
1236 {
1237 static struct object_info blank_oi = OBJECT_INFO_INIT;
1238 struct pack_entry e;
1239 int rtype;
1240 const struct object_id *real = oid;
1241 int already_retried = 0;
1242
1243 if (flags & OBJECT_INFO_LOOKUP_REPLACE)
1244 real = lookup_replace_object(r, oid);
1245
1246 if (is_null_oid(real))
1247 return -1;
1248
1249 if (!oi)
1250 oi = &blank_oi;
1251
1252 if (!(flags & OBJECT_INFO_SKIP_CACHED)) {
1253 struct cached_object *co = find_cached_object(real->hash);
1254 if (co) {
1255 if (oi->typep)
1256 *(oi->typep) = co->type;
1257 if (oi->sizep)
1258 *(oi->sizep) = co->size;
1259 if (oi->disk_sizep)
1260 *(oi->disk_sizep) = 0;
1261 if (oi->delta_base_sha1)
1262 hashclr(oi->delta_base_sha1);
1263 if (oi->type_name)
1264 strbuf_addstr(oi->type_name, type_name(co->type));
1265 if (oi->contentp)
1266 *oi->contentp = xmemdupz(co->buf, co->size);
1267 oi->whence = OI_CACHED;
1268 return 0;
1269 }
1270 }
1271
1272 while (1) {
1273 if (find_pack_entry(r, real->hash, &e))
1274 break;
1275
1276 if (flags & OBJECT_INFO_IGNORE_LOOSE)
1277 return -1;
1278
1279 /* Most likely it's a loose object. */
1280 if (!sha1_loose_object_info(r, real->hash, oi, flags))
1281 return 0;
1282
1283 /* Not a loose object; someone else may have just packed it. */
1284 if (!(flags & OBJECT_INFO_QUICK)) {
1285 reprepare_packed_git(r);
1286 if (find_pack_entry(r, real->hash, &e))
1287 break;
1288 }
1289
1290 /* Check if it is a missing object */
1291 if (fetch_if_missing && repository_format_partial_clone &&
1292 !already_retried && r == the_repository) {
1293 /*
1294 * TODO Investigate having fetch_object() return
1295 * TODO error/success and stopping the music here.
1296 * TODO Pass a repository struct through fetch_object,
1297 * such that arbitrary repositories work.
1298 */
1299 fetch_object(repository_format_partial_clone, real->hash);
1300 already_retried = 1;
1301 continue;
1302 }
1303
1304 return -1;
1305 }
1306
1307 if (oi == &blank_oi)
1308 /*
1309 * We know that the caller doesn't actually need the
1310 * information below, so return early.
1311 */
1312 return 0;
1313 rtype = packed_object_info(r, e.p, e.offset, oi);
1314 if (rtype < 0) {
1315 mark_bad_packed_object(e.p, real->hash);
1316 return oid_object_info_extended(r, real, oi, 0);
1317 } else if (oi->whence == OI_PACKED) {
1318 oi->u.packed.offset = e.offset;
1319 oi->u.packed.pack = e.p;
1320 oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
1321 rtype == OBJ_OFS_DELTA);
1322 }
1323
1324 return 0;
1325 }
1326
1327 /* returns enum object_type or negative */
1328 int oid_object_info(struct repository *r,
1329 const struct object_id *oid,
1330 unsigned long *sizep)
1331 {
1332 enum object_type type;
1333 struct object_info oi = OBJECT_INFO_INIT;
1334
1335 oi.typep = &type;
1336 oi.sizep = sizep;
1337 if (oid_object_info_extended(r, oid, &oi,
1338 OBJECT_INFO_LOOKUP_REPLACE) < 0)
1339 return -1;
1340 return type;
1341 }
1342
1343 static void *read_object(const unsigned char *sha1, enum object_type *type,
1344 unsigned long *size)
1345 {
1346 struct object_id oid;
1347 struct object_info oi = OBJECT_INFO_INIT;
1348 void *content;
1349 oi.typep = type;
1350 oi.sizep = size;
1351 oi.contentp = &content;
1352
1353 hashcpy(oid.hash, sha1);
1354
1355 if (oid_object_info_extended(the_repository, &oid, &oi, 0) < 0)
1356 return NULL;
1357 return content;
1358 }
1359
1360 int pretend_object_file(void *buf, unsigned long len, enum object_type type,
1361 struct object_id *oid)
1362 {
1363 struct cached_object *co;
1364
1365 hash_object_file(buf, len, type_name(type), oid);
1366 if (has_sha1_file(oid->hash) || find_cached_object(oid->hash))
1367 return 0;
1368 ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
1369 co = &cached_objects[cached_object_nr++];
1370 co->size = len;
1371 co->type = type;
1372 co->buf = xmalloc(len);
1373 memcpy(co->buf, buf, len);
1374 hashcpy(co->sha1, oid->hash);
1375 return 0;
1376 }
1377
1378 /*
1379 * This function dies on corrupt objects; the callers who want to
1380 * deal with them should arrange to call read_object() and give error
1381 * messages themselves.
1382 */
1383 void *read_object_file_extended(const struct object_id *oid,
1384 enum object_type *type,
1385 unsigned long *size,
1386 int lookup_replace)
1387 {
1388 void *data;
1389 const struct packed_git *p;
1390 const char *path;
1391 struct stat st;
1392 const struct object_id *repl = lookup_replace ?
1393 lookup_replace_object(the_repository, oid) : oid;
1394
1395 errno = 0;
1396 data = read_object(repl->hash, type, size);
1397 if (data)
1398 return data;
1399
1400 if (errno && errno != ENOENT)
1401 die_errno("failed to read object %s", oid_to_hex(oid));
1402
1403 /* die if we replaced an object with one that does not exist */
1404 if (repl != oid)
1405 die("replacement %s not found for %s",
1406 oid_to_hex(repl), oid_to_hex(oid));
1407
1408 if (!stat_sha1_file(the_repository, repl->hash, &st, &path))
1409 die("loose object %s (stored in %s) is corrupt",
1410 oid_to_hex(repl), path);
1411
1412 if ((p = has_packed_and_bad(repl->hash)) != NULL)
1413 die("packed object %s (stored in %s) is corrupt",
1414 oid_to_hex(repl), p->pack_name);
1415
1416 return NULL;
1417 }
1418
1419 void *read_object_with_reference(const struct object_id *oid,
1420 const char *required_type_name,
1421 unsigned long *size,
1422 struct object_id *actual_oid_return)
1423 {
1424 enum object_type type, required_type;
1425 void *buffer;
1426 unsigned long isize;
1427 struct object_id actual_oid;
1428
1429 required_type = type_from_string(required_type_name);
1430 oidcpy(&actual_oid, oid);
1431 while (1) {
1432 int ref_length = -1;
1433 const char *ref_type = NULL;
1434
1435 buffer = read_object_file(&actual_oid, &type, &isize);
1436 if (!buffer)
1437 return NULL;
1438 if (type == required_type) {
1439 *size = isize;
1440 if (actual_oid_return)
1441 oidcpy(actual_oid_return, &actual_oid);
1442 return buffer;
1443 }
1444 /* Handle references */
1445 else if (type == OBJ_COMMIT)
1446 ref_type = "tree ";
1447 else if (type == OBJ_TAG)
1448 ref_type = "object ";
1449 else {
1450 free(buffer);
1451 return NULL;
1452 }
1453 ref_length = strlen(ref_type);
1454
1455 if (ref_length + GIT_SHA1_HEXSZ > isize ||
1456 memcmp(buffer, ref_type, ref_length) ||
1457 get_oid_hex((char *) buffer + ref_length, &actual_oid)) {
1458 free(buffer);
1459 return NULL;
1460 }
1461 free(buffer);
1462 /* Now we have the ID of the referred-to object in
1463 * actual_oid. Check again. */
1464 }
1465 }
1466
1467 static void write_object_file_prepare(const void *buf, unsigned long len,
1468 const char *type, struct object_id *oid,
1469 char *hdr, int *hdrlen)
1470 {
1471 git_hash_ctx c;
1472
1473 /* Generate the header */
1474 *hdrlen = xsnprintf(hdr, *hdrlen, "%s %lu", type, len)+1;
1475
1476 /* Sha1.. */
1477 the_hash_algo->init_fn(&c);
1478 the_hash_algo->update_fn(&c, hdr, *hdrlen);
1479 the_hash_algo->update_fn(&c, buf, len);
1480 the_hash_algo->final_fn(oid->hash, &c);
1481 }
1482
1483 /*
1484 * Move the just written object into its final resting place.
1485 */
1486 int finalize_object_file(const char *tmpfile, const char *filename)
1487 {
1488 int ret = 0;
1489
1490 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
1491 goto try_rename;
1492 else if (link(tmpfile, filename))
1493 ret = errno;
1494
1495 /*
1496 * Coda hack - coda doesn't like cross-directory links,
1497 * so we fall back to a rename, which will mean that it
1498 * won't be able to check collisions, but that's not a
1499 * big deal.
1500 *
1501 * The same holds for FAT formatted media.
1502 *
1503 * When this succeeds, we just return. We have nothing
1504 * left to unlink.
1505 */
1506 if (ret && ret != EEXIST) {
1507 try_rename:
1508 if (!rename(tmpfile, filename))
1509 goto out;
1510 ret = errno;
1511 }
1512 unlink_or_warn(tmpfile);
1513 if (ret) {
1514 if (ret != EEXIST) {
1515 return error_errno("unable to write sha1 filename %s", filename);
1516 }
1517 /* FIXME!!! Collision check here ? */
1518 }
1519
1520 out:
1521 if (adjust_shared_perm(filename))
1522 return error("unable to set permission to '%s'", filename);
1523 return 0;
1524 }
1525
1526 static int write_buffer(int fd, const void *buf, size_t len)
1527 {
1528 if (write_in_full(fd, buf, len) < 0)
1529 return error_errno("file write error");
1530 return 0;
1531 }
1532
1533 int hash_object_file(const void *buf, unsigned long len, const char *type,
1534 struct object_id *oid)
1535 {
1536 char hdr[MAX_HEADER_LEN];
1537 int hdrlen = sizeof(hdr);
1538 write_object_file_prepare(buf, len, type, oid, hdr, &hdrlen);
1539 return 0;
1540 }
1541
1542 /* Finalize a file on disk, and close it. */
1543 static void close_sha1_file(int fd)
1544 {
1545 if (fsync_object_files)
1546 fsync_or_die(fd, "sha1 file");
1547 if (close(fd) != 0)
1548 die_errno("error when closing sha1 file");
1549 }
1550
1551 /* Size of directory component, including the ending '/' */
1552 static inline int directory_size(const char *filename)
1553 {
1554 const char *s = strrchr(filename, '/');
1555 if (!s)
1556 return 0;
1557 return s - filename + 1;
1558 }
1559
1560 /*
1561 * This creates a temporary file in the same directory as the final
1562 * 'filename'
1563 *
1564 * We want to avoid cross-directory filename renames, because those
1565 * can have problems on various filesystems (FAT, NFS, Coda).
1566 */
1567 static int create_tmpfile(struct strbuf *tmp, const char *filename)
1568 {
1569 int fd, dirlen = directory_size(filename);
1570
1571 strbuf_reset(tmp);
1572 strbuf_add(tmp, filename, dirlen);
1573 strbuf_addstr(tmp, "tmp_obj_XXXXXX");
1574 fd = git_mkstemp_mode(tmp->buf, 0444);
1575 if (fd < 0 && dirlen && errno == ENOENT) {
1576 /*
1577 * Make sure the directory exists; note that the contents
1578 * of the buffer are undefined after mkstemp returns an
1579 * error, so we have to rewrite the whole buffer from
1580 * scratch.
1581 */
1582 strbuf_reset(tmp);
1583 strbuf_add(tmp, filename, dirlen - 1);
1584 if (mkdir(tmp->buf, 0777) && errno != EEXIST)
1585 return -1;
1586 if (adjust_shared_perm(tmp->buf))
1587 return -1;
1588
1589 /* Try again */
1590 strbuf_addstr(tmp, "/tmp_obj_XXXXXX");
1591 fd = git_mkstemp_mode(tmp->buf, 0444);
1592 }
1593 return fd;
1594 }
1595
1596 static int write_loose_object(const struct object_id *oid, char *hdr,
1597 int hdrlen, const void *buf, unsigned long len,
1598 time_t mtime)
1599 {
1600 int fd, ret;
1601 unsigned char compressed[4096];
1602 git_zstream stream;
1603 git_hash_ctx c;
1604 struct object_id parano_oid;
1605 static struct strbuf tmp_file = STRBUF_INIT;
1606 static struct strbuf filename = STRBUF_INIT;
1607
1608 strbuf_reset(&filename);
1609 sha1_file_name(the_repository, &filename, oid->hash);
1610
1611 fd = create_tmpfile(&tmp_file, filename.buf);
1612 if (fd < 0) {
1613 if (errno == EACCES)
1614 return error("insufficient permission for adding an object to repository database %s", get_object_directory());
1615 else
1616 return error_errno("unable to create temporary file");
1617 }
1618
1619 /* Set it up */
1620 git_deflate_init(&stream, zlib_compression_level);
1621 stream.next_out = compressed;
1622 stream.avail_out = sizeof(compressed);
1623 the_hash_algo->init_fn(&c);
1624
1625 /* First header.. */
1626 stream.next_in = (unsigned char *)hdr;
1627 stream.avail_in = hdrlen;
1628 while (git_deflate(&stream, 0) == Z_OK)
1629 ; /* nothing */
1630 the_hash_algo->update_fn(&c, hdr, hdrlen);
1631
1632 /* Then the data itself.. */
1633 stream.next_in = (void *)buf;
1634 stream.avail_in = len;
1635 do {
1636 unsigned char *in0 = stream.next_in;
1637 ret = git_deflate(&stream, Z_FINISH);
1638 the_hash_algo->update_fn(&c, in0, stream.next_in - in0);
1639 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
1640 die("unable to write sha1 file");
1641 stream.next_out = compressed;
1642 stream.avail_out = sizeof(compressed);
1643 } while (ret == Z_OK);
1644
1645 if (ret != Z_STREAM_END)
1646 die("unable to deflate new object %s (%d)", oid_to_hex(oid),
1647 ret);
1648 ret = git_deflate_end_gently(&stream);
1649 if (ret != Z_OK)
1650 die("deflateEnd on object %s failed (%d)", oid_to_hex(oid),
1651 ret);
1652 the_hash_algo->final_fn(parano_oid.hash, &c);
1653 if (oidcmp(oid, &parano_oid) != 0)
1654 die("confused by unstable object source data for %s",
1655 oid_to_hex(oid));
1656
1657 close_sha1_file(fd);
1658
1659 if (mtime) {
1660 struct utimbuf utb;
1661 utb.actime = mtime;
1662 utb.modtime = mtime;
1663 if (utime(tmp_file.buf, &utb) < 0)
1664 warning_errno("failed utime() on %s", tmp_file.buf);
1665 }
1666
1667 return finalize_object_file(tmp_file.buf, filename.buf);
1668 }
1669
1670 static int freshen_loose_object(const unsigned char *sha1)
1671 {
1672 return check_and_freshen(sha1, 1);
1673 }
1674
1675 static int freshen_packed_object(const unsigned char *sha1)
1676 {
1677 struct pack_entry e;
1678 if (!find_pack_entry(the_repository, sha1, &e))
1679 return 0;
1680 if (e.p->freshened)
1681 return 1;
1682 if (!freshen_file(e.p->pack_name))
1683 return 0;
1684 e.p->freshened = 1;
1685 return 1;
1686 }
1687
1688 int write_object_file(const void *buf, unsigned long len, const char *type,
1689 struct object_id *oid)
1690 {
1691 char hdr[MAX_HEADER_LEN];
1692 int hdrlen = sizeof(hdr);
1693
1694 /* Normally if we have it in the pack then we do not bother writing
1695 * it out into .git/objects/??/?{38} file.
1696 */
1697 write_object_file_prepare(buf, len, type, oid, hdr, &hdrlen);
1698 if (freshen_packed_object(oid->hash) || freshen_loose_object(oid->hash))
1699 return 0;
1700 return write_loose_object(oid, hdr, hdrlen, buf, len, 0);
1701 }
1702
1703 int hash_object_file_literally(const void *buf, unsigned long len,
1704 const char *type, struct object_id *oid,
1705 unsigned flags)
1706 {
1707 char *header;
1708 int hdrlen, status = 0;
1709
1710 /* type string, SP, %lu of the length plus NUL must fit this */
1711 hdrlen = strlen(type) + MAX_HEADER_LEN;
1712 header = xmalloc(hdrlen);
1713 write_object_file_prepare(buf, len, type, oid, header, &hdrlen);
1714
1715 if (!(flags & HASH_WRITE_OBJECT))
1716 goto cleanup;
1717 if (freshen_packed_object(oid->hash) || freshen_loose_object(oid->hash))
1718 goto cleanup;
1719 status = write_loose_object(oid, header, hdrlen, buf, len, 0);
1720
1721 cleanup:
1722 free(header);
1723 return status;
1724 }
1725
1726 int force_object_loose(const struct object_id *oid, time_t mtime)
1727 {
1728 void *buf;
1729 unsigned long len;
1730 enum object_type type;
1731 char hdr[MAX_HEADER_LEN];
1732 int hdrlen;
1733 int ret;
1734
1735 if (has_loose_object(oid->hash))
1736 return 0;
1737 buf = read_object(oid->hash, &type, &len);
1738 if (!buf)
1739 return error("cannot read sha1_file for %s", oid_to_hex(oid));
1740 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", type_name(type), len) + 1;
1741 ret = write_loose_object(oid, hdr, hdrlen, buf, len, mtime);
1742 free(buf);
1743
1744 return ret;
1745 }
1746
1747 int has_sha1_file_with_flags(const unsigned char *sha1, int flags)
1748 {
1749 struct object_id oid;
1750 if (!startup_info->have_repository)
1751 return 0;
1752 hashcpy(oid.hash, sha1);
1753 return oid_object_info_extended(the_repository, &oid, NULL,
1754 flags | OBJECT_INFO_SKIP_CACHED) >= 0;
1755 }
1756
1757 int has_object_file(const struct object_id *oid)
1758 {
1759 return has_sha1_file(oid->hash);
1760 }
1761
1762 int has_object_file_with_flags(const struct object_id *oid, int flags)
1763 {
1764 return has_sha1_file_with_flags(oid->hash, flags);
1765 }
1766
1767 static void check_tree(const void *buf, size_t size)
1768 {
1769 struct tree_desc desc;
1770 struct name_entry entry;
1771
1772 init_tree_desc(&desc, buf, size);
1773 while (tree_entry(&desc, &entry))
1774 /* do nothing
1775 * tree_entry() will die() on malformed entries */
1776 ;
1777 }
1778
1779 static void check_commit(const void *buf, size_t size)
1780 {
1781 struct commit c;
1782 memset(&c, 0, sizeof(c));
1783 if (parse_commit_buffer(&c, buf, size))
1784 die("corrupt commit");
1785 }
1786
1787 static void check_tag(const void *buf, size_t size)
1788 {
1789 struct tag t;
1790 memset(&t, 0, sizeof(t));
1791 if (parse_tag_buffer(&t, buf, size))
1792 die("corrupt tag");
1793 }
1794
1795 static int index_mem(struct object_id *oid, void *buf, size_t size,
1796 enum object_type type,
1797 const char *path, unsigned flags)
1798 {
1799 int ret, re_allocated = 0;
1800 int write_object = flags & HASH_WRITE_OBJECT;
1801
1802 if (!type)
1803 type = OBJ_BLOB;
1804
1805 /*
1806 * Convert blobs to git internal format
1807 */
1808 if ((type == OBJ_BLOB) && path) {
1809 struct strbuf nbuf = STRBUF_INIT;
1810 if (convert_to_git(&the_index, path, buf, size, &nbuf,
1811 get_conv_flags(flags))) {
1812 buf = strbuf_detach(&nbuf, &size);
1813 re_allocated = 1;
1814 }
1815 }
1816 if (flags & HASH_FORMAT_CHECK) {
1817 if (type == OBJ_TREE)
1818 check_tree(buf, size);
1819 if (type == OBJ_COMMIT)
1820 check_commit(buf, size);
1821 if (type == OBJ_TAG)
1822 check_tag(buf, size);
1823 }
1824
1825 if (write_object)
1826 ret = write_object_file(buf, size, type_name(type), oid);
1827 else
1828 ret = hash_object_file(buf, size, type_name(type), oid);
1829 if (re_allocated)
1830 free(buf);
1831 return ret;
1832 }
1833
1834 static int index_stream_convert_blob(struct object_id *oid, int fd,
1835 const char *path, unsigned flags)
1836 {
1837 int ret;
1838 const int write_object = flags & HASH_WRITE_OBJECT;
1839 struct strbuf sbuf = STRBUF_INIT;
1840
1841 assert(path);
1842 assert(would_convert_to_git_filter_fd(path));
1843
1844 convert_to_git_filter_fd(&the_index, path, fd, &sbuf,
1845 get_conv_flags(flags));
1846
1847 if (write_object)
1848 ret = write_object_file(sbuf.buf, sbuf.len, type_name(OBJ_BLOB),
1849 oid);
1850 else
1851 ret = hash_object_file(sbuf.buf, sbuf.len, type_name(OBJ_BLOB),
1852 oid);
1853 strbuf_release(&sbuf);
1854 return ret;
1855 }
1856
1857 static int index_pipe(struct object_id *oid, int fd, enum object_type type,
1858 const char *path, unsigned flags)
1859 {
1860 struct strbuf sbuf = STRBUF_INIT;
1861 int ret;
1862
1863 if (strbuf_read(&sbuf, fd, 4096) >= 0)
1864 ret = index_mem(oid, sbuf.buf, sbuf.len, type, path, flags);
1865 else
1866 ret = -1;
1867 strbuf_release(&sbuf);
1868 return ret;
1869 }
1870
1871 #define SMALL_FILE_SIZE (32*1024)
1872
1873 static int index_core(struct object_id *oid, int fd, size_t size,
1874 enum object_type type, const char *path,
1875 unsigned flags)
1876 {
1877 int ret;
1878
1879 if (!size) {
1880 ret = index_mem(oid, "", size, type, path, flags);
1881 } else if (size <= SMALL_FILE_SIZE) {
1882 char *buf = xmalloc(size);
1883 ssize_t read_result = read_in_full(fd, buf, size);
1884 if (read_result < 0)
1885 ret = error_errno("read error while indexing %s",
1886 path ? path : "<unknown>");
1887 else if (read_result != size)
1888 ret = error("short read while indexing %s",
1889 path ? path : "<unknown>");
1890 else
1891 ret = index_mem(oid, buf, size, type, path, flags);
1892 free(buf);
1893 } else {
1894 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
1895 ret = index_mem(oid, buf, size, type, path, flags);
1896 munmap(buf, size);
1897 }
1898 return ret;
1899 }
1900
1901 /*
1902 * This creates one packfile per large blob unless bulk-checkin
1903 * machinery is "plugged".
1904 *
1905 * This also bypasses the usual "convert-to-git" dance, and that is on
1906 * purpose. We could write a streaming version of the converting
1907 * functions and insert that before feeding the data to fast-import
1908 * (or equivalent in-core API described above). However, that is
1909 * somewhat complicated, as we do not know the size of the filter
1910 * result, which we need to know beforehand when writing a git object.
1911 * Since the primary motivation for trying to stream from the working
1912 * tree file and to avoid mmaping it in core is to deal with large
1913 * binary blobs, they generally do not want to get any conversion, and
1914 * callers should avoid this code path when filters are requested.
1915 */
1916 static int index_stream(struct object_id *oid, int fd, size_t size,
1917 enum object_type type, const char *path,
1918 unsigned flags)
1919 {
1920 return index_bulk_checkin(oid, fd, size, type, path, flags);
1921 }
1922
1923 int index_fd(struct object_id *oid, int fd, struct stat *st,
1924 enum object_type type, const char *path, unsigned flags)
1925 {
1926 int ret;
1927
1928 /*
1929 * Call xsize_t() only when needed to avoid potentially unnecessary
1930 * die() for large files.
1931 */
1932 if (type == OBJ_BLOB && path && would_convert_to_git_filter_fd(path))
1933 ret = index_stream_convert_blob(oid, fd, path, flags);
1934 else if (!S_ISREG(st->st_mode))
1935 ret = index_pipe(oid, fd, type, path, flags);
1936 else if (st->st_size <= big_file_threshold || type != OBJ_BLOB ||
1937 (path && would_convert_to_git(&the_index, path)))
1938 ret = index_core(oid, fd, xsize_t(st->st_size), type, path,
1939 flags);
1940 else
1941 ret = index_stream(oid, fd, xsize_t(st->st_size), type, path,
1942 flags);
1943 close(fd);
1944 return ret;
1945 }
1946
1947 int index_path(struct object_id *oid, const char *path, struct stat *st, unsigned flags)
1948 {
1949 int fd;
1950 struct strbuf sb = STRBUF_INIT;
1951 int rc = 0;
1952
1953 switch (st->st_mode & S_IFMT) {
1954 case S_IFREG:
1955 fd = open(path, O_RDONLY);
1956 if (fd < 0)
1957 return error_errno("open(\"%s\")", path);
1958 if (index_fd(oid, fd, st, OBJ_BLOB, path, flags) < 0)
1959 return error("%s: failed to insert into database",
1960 path);
1961 break;
1962 case S_IFLNK:
1963 if (strbuf_readlink(&sb, path, st->st_size))
1964 return error_errno("readlink(\"%s\")", path);
1965 if (!(flags & HASH_WRITE_OBJECT))
1966 hash_object_file(sb.buf, sb.len, blob_type, oid);
1967 else if (write_object_file(sb.buf, sb.len, blob_type, oid))
1968 rc = error("%s: failed to insert into database", path);
1969 strbuf_release(&sb);
1970 break;
1971 case S_IFDIR:
1972 return resolve_gitlink_ref(path, "HEAD", oid);
1973 default:
1974 return error("%s: unsupported file type", path);
1975 }
1976 return rc;
1977 }
1978
1979 int read_pack_header(int fd, struct pack_header *header)
1980 {
1981 if (read_in_full(fd, header, sizeof(*header)) != sizeof(*header))
1982 /* "eof before pack header was fully read" */
1983 return PH_ERROR_EOF;
1984
1985 if (header->hdr_signature != htonl(PACK_SIGNATURE))
1986 /* "protocol error (pack signature mismatch detected)" */
1987 return PH_ERROR_PACK_SIGNATURE;
1988 if (!pack_version_ok(header->hdr_version))
1989 /* "protocol error (pack version unsupported)" */
1990 return PH_ERROR_PROTOCOL;
1991 return 0;
1992 }
1993
1994 void assert_oid_type(const struct object_id *oid, enum object_type expect)
1995 {
1996 enum object_type type = oid_object_info(the_repository, oid, NULL);
1997 if (type < 0)
1998 die("%s is not a valid object", oid_to_hex(oid));
1999 if (type != expect)
2000 die("%s is not a valid '%s' object", oid_to_hex(oid),
2001 type_name(expect));
2002 }
2003
2004 int for_each_file_in_obj_subdir(unsigned int subdir_nr,
2005 struct strbuf *path,
2006 each_loose_object_fn obj_cb,
2007 each_loose_cruft_fn cruft_cb,
2008 each_loose_subdir_fn subdir_cb,
2009 void *data)
2010 {
2011 size_t origlen, baselen;
2012 DIR *dir;
2013 struct dirent *de;
2014 int r = 0;
2015 struct object_id oid;
2016
2017 if (subdir_nr > 0xff)
2018 BUG("invalid loose object subdirectory: %x", subdir_nr);
2019
2020 origlen = path->len;
2021 strbuf_complete(path, '/');
2022 strbuf_addf(path, "%02x", subdir_nr);
2023
2024 dir = opendir(path->buf);
2025 if (!dir) {
2026 if (errno != ENOENT)
2027 r = error_errno("unable to open %s", path->buf);
2028 strbuf_setlen(path, origlen);
2029 return r;
2030 }
2031
2032 oid.hash[0] = subdir_nr;
2033 strbuf_addch(path, '/');
2034 baselen = path->len;
2035
2036 while ((de = readdir(dir))) {
2037 size_t namelen;
2038 if (is_dot_or_dotdot(de->d_name))
2039 continue;
2040
2041 namelen = strlen(de->d_name);
2042 strbuf_setlen(path, baselen);
2043 strbuf_add(path, de->d_name, namelen);
2044 if (namelen == GIT_SHA1_HEXSZ - 2 &&
2045 !hex_to_bytes(oid.hash + 1, de->d_name,
2046 GIT_SHA1_RAWSZ - 1)) {
2047 if (obj_cb) {
2048 r = obj_cb(&oid, path->buf, data);
2049 if (r)
2050 break;
2051 }
2052 continue;
2053 }
2054
2055 if (cruft_cb) {
2056 r = cruft_cb(de->d_name, path->buf, data);
2057 if (r)
2058 break;
2059 }
2060 }
2061 closedir(dir);
2062
2063 strbuf_setlen(path, baselen - 1);
2064 if (!r && subdir_cb)
2065 r = subdir_cb(subdir_nr, path->buf, data);
2066
2067 strbuf_setlen(path, origlen);
2068
2069 return r;
2070 }
2071
2072 int for_each_loose_file_in_objdir_buf(struct strbuf *path,
2073 each_loose_object_fn obj_cb,
2074 each_loose_cruft_fn cruft_cb,
2075 each_loose_subdir_fn subdir_cb,
2076 void *data)
2077 {
2078 int r = 0;
2079 int i;
2080
2081 for (i = 0; i < 256; i++) {
2082 r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb,
2083 subdir_cb, data);
2084 if (r)
2085 break;
2086 }
2087
2088 return r;
2089 }
2090
2091 int for_each_loose_file_in_objdir(const char *path,
2092 each_loose_object_fn obj_cb,
2093 each_loose_cruft_fn cruft_cb,
2094 each_loose_subdir_fn subdir_cb,
2095 void *data)
2096 {
2097 struct strbuf buf = STRBUF_INIT;
2098 int r;
2099
2100 strbuf_addstr(&buf, path);
2101 r = for_each_loose_file_in_objdir_buf(&buf, obj_cb, cruft_cb,
2102 subdir_cb, data);
2103 strbuf_release(&buf);
2104
2105 return r;
2106 }
2107
2108 struct loose_alt_odb_data {
2109 each_loose_object_fn *cb;
2110 void *data;
2111 };
2112
2113 static int loose_from_alt_odb(struct alternate_object_database *alt,
2114 void *vdata)
2115 {
2116 struct loose_alt_odb_data *data = vdata;
2117 struct strbuf buf = STRBUF_INIT;
2118 int r;
2119
2120 strbuf_addstr(&buf, alt->path);
2121 r = for_each_loose_file_in_objdir_buf(&buf,
2122 data->cb, NULL, NULL,
2123 data->data);
2124 strbuf_release(&buf);
2125 return r;
2126 }
2127
2128 int for_each_loose_object(each_loose_object_fn cb, void *data, unsigned flags)
2129 {
2130 struct loose_alt_odb_data alt;
2131 int r;
2132
2133 r = for_each_loose_file_in_objdir(get_object_directory(),
2134 cb, NULL, NULL, data);
2135 if (r)
2136 return r;
2137
2138 if (flags & FOR_EACH_OBJECT_LOCAL_ONLY)
2139 return 0;
2140
2141 alt.cb = cb;
2142 alt.data = data;
2143 return foreach_alt_odb(loose_from_alt_odb, &alt);
2144 }
2145
2146 static int check_stream_sha1(git_zstream *stream,
2147 const char *hdr,
2148 unsigned long size,
2149 const char *path,
2150 const unsigned char *expected_sha1)
2151 {
2152 git_hash_ctx c;
2153 unsigned char real_sha1[GIT_MAX_RAWSZ];
2154 unsigned char buf[4096];
2155 unsigned long total_read;
2156 int status = Z_OK;
2157
2158 the_hash_algo->init_fn(&c);
2159 the_hash_algo->update_fn(&c, hdr, stream->total_out);
2160
2161 /*
2162 * We already read some bytes into hdr, but the ones up to the NUL
2163 * do not count against the object's content size.
2164 */
2165 total_read = stream->total_out - strlen(hdr) - 1;
2166
2167 /*
2168 * This size comparison must be "<=" to read the final zlib packets;
2169 * see the comment in unpack_sha1_rest for details.
2170 */
2171 while (total_read <= size &&
2172 (status == Z_OK || status == Z_BUF_ERROR)) {
2173 stream->next_out = buf;
2174 stream->avail_out = sizeof(buf);
2175 if (size - total_read < stream->avail_out)
2176 stream->avail_out = size - total_read;
2177 status = git_inflate(stream, Z_FINISH);
2178 the_hash_algo->update_fn(&c, buf, stream->next_out - buf);
2179 total_read += stream->next_out - buf;
2180 }
2181 git_inflate_end(stream);
2182
2183 if (status != Z_STREAM_END) {
2184 error("corrupt loose object '%s'", sha1_to_hex(expected_sha1));
2185 return -1;
2186 }
2187 if (stream->avail_in) {
2188 error("garbage at end of loose object '%s'",
2189 sha1_to_hex(expected_sha1));
2190 return -1;
2191 }
2192
2193 the_hash_algo->final_fn(real_sha1, &c);
2194 if (hashcmp(expected_sha1, real_sha1)) {
2195 error("sha1 mismatch for %s (expected %s)", path,
2196 sha1_to_hex(expected_sha1));
2197 return -1;
2198 }
2199
2200 return 0;
2201 }
2202
2203 int read_loose_object(const char *path,
2204 const struct object_id *expected_oid,
2205 enum object_type *type,
2206 unsigned long *size,
2207 void **contents)
2208 {
2209 int ret = -1;
2210 void *map = NULL;
2211 unsigned long mapsize;
2212 git_zstream stream;
2213 char hdr[MAX_HEADER_LEN];
2214
2215 *contents = NULL;
2216
2217 map = map_sha1_file_1(the_repository, path, NULL, &mapsize);
2218 if (!map) {
2219 error_errno("unable to mmap %s", path);
2220 goto out;
2221 }
2222
2223 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) {
2224 error("unable to unpack header of %s", path);
2225 goto out;
2226 }
2227
2228 *type = parse_sha1_header(hdr, size);
2229 if (*type < 0) {
2230 error("unable to parse header of %s", path);
2231 git_inflate_end(&stream);
2232 goto out;
2233 }
2234
2235 if (*type == OBJ_BLOB) {
2236 if (check_stream_sha1(&stream, hdr, *size, path, expected_oid->hash) < 0)
2237 goto out;
2238 } else {
2239 *contents = unpack_sha1_rest(&stream, hdr, *size, expected_oid->hash);
2240 if (!*contents) {
2241 error("unable to unpack contents of %s", path);
2242 git_inflate_end(&stream);
2243 goto out;
2244 }
2245 if (check_object_signature(expected_oid, *contents,
2246 *size, type_name(*type))) {
2247 error("sha1 mismatch for %s (expected %s)", path,
2248 oid_to_hex(expected_oid));
2249 free(*contents);
2250 goto out;
2251 }
2252 }
2253
2254 ret = 0; /* everything checks out */
2255
2256 out:
2257 if (map)
2258 munmap(map, mapsize);
2259 return ret;
2260 }