2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
6 * This handles basic git sha1 object files - packing, unpacking,
10 #include "string-list.h"
16 #include "run-command.h"
19 #include "tree-walk.h"
21 #include "pack-revindex.h"
22 #include "sha1-lookup.h"
23 #include "bulk-checkin.h"
24 #include "streaming.h"
28 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
29 #define O_NOATIME 01000000
35 #define SZ_FMT PRIuMAX
36 static inline uintmax_t sz_fmt(size_t s
) { return s
; }
38 const unsigned char null_sha1
[20];
41 * This is meant to hold a *small* number of objects that you would
42 * want read_sha1_file() to be able to return, but yet you do not want
43 * to write them into the object store (e.g. a browse-only
46 static struct cached_object
{
47 unsigned char sha1
[20];
48 enum object_type type
;
52 static int cached_object_nr
, cached_object_alloc
;
54 static struct cached_object empty_tree
= {
55 EMPTY_TREE_SHA1_BIN_LITERAL
,
62 * A pointer to the last packed_git in which an object was found.
63 * When an object is sought, we look in this packfile first, because
64 * objects that are looked up at similar times are often in the same
65 * packfile as one another.
67 static struct packed_git
*last_found_pack
;
69 static struct cached_object
*find_cached_object(const unsigned char *sha1
)
72 struct cached_object
*co
= cached_objects
;
74 for (i
= 0; i
< cached_object_nr
; i
++, co
++) {
75 if (!hashcmp(co
->sha1
, sha1
))
78 if (!hashcmp(sha1
, empty_tree
.sha1
))
83 int mkdir_in_gitdir(const char *path
)
85 if (mkdir(path
, 0777)) {
86 int saved_errno
= errno
;
88 struct strbuf sb
= STRBUF_INIT
;
93 * Are we looking at a path in a symlinked worktree
94 * whose original repository does not yet have it?
95 * e.g. .git/rr-cache pointing at its original
96 * repository in which the user hasn't performed any
97 * conflict resolution yet?
99 if (lstat(path
, &st
) || !S_ISLNK(st
.st_mode
) ||
100 strbuf_readlink(&sb
, path
, st
.st_size
) ||
101 !is_absolute_path(sb
.buf
) ||
102 mkdir(sb
.buf
, 0777)) {
109 return adjust_shared_perm(path
);
112 enum scld_error
safe_create_leading_directories(char *path
)
114 char *next_component
= path
+ offset_1st_component(path
);
115 enum scld_error ret
= SCLD_OK
;
117 while (ret
== SCLD_OK
&& next_component
) {
119 char *slash
= next_component
, slash_character
;
121 while (*slash
&& !is_dir_sep(*slash
))
127 next_component
= slash
+ 1;
128 while (is_dir_sep(*next_component
))
130 if (!*next_component
)
133 slash_character
= *slash
;
135 if (!stat(path
, &st
)) {
137 if (!S_ISDIR(st
.st_mode
))
139 } else if (mkdir(path
, 0777)) {
140 if (errno
== EEXIST
&&
141 !stat(path
, &st
) && S_ISDIR(st
.st_mode
))
142 ; /* somebody created it since we checked */
143 else if (errno
== ENOENT
)
145 * Either mkdir() failed because
146 * somebody just pruned the containing
147 * directory, or stat() failed because
148 * the file that was in our way was
149 * just removed. Either way, inform
150 * the caller that it might be worth
156 } else if (adjust_shared_perm(path
)) {
159 *slash
= slash_character
;
164 enum scld_error
safe_create_leading_directories_const(const char *path
)
166 /* path points to cache entries, so xstrdup before messing with it */
167 char *buf
= xstrdup(path
);
168 enum scld_error result
= safe_create_leading_directories(buf
);
173 static void fill_sha1_path(char *pathbuf
, const unsigned char *sha1
)
176 for (i
= 0; i
< 20; i
++) {
177 static char hex
[] = "0123456789abcdef";
178 unsigned int val
= sha1
[i
];
179 char *pos
= pathbuf
+ i
*2 + (i
> 0);
180 *pos
++ = hex
[val
>> 4];
181 *pos
= hex
[val
& 0xf];
185 const char *sha1_file_name(const unsigned char *sha1
)
187 static char buf
[PATH_MAX
];
191 objdir
= get_object_directory();
192 len
= strlen(objdir
);
194 /* '/' + sha1(2) + '/' + sha1(38) + '\0' */
195 if (len
+ 43 > PATH_MAX
)
196 die("insanely long object directory %s", objdir
);
197 memcpy(buf
, objdir
, len
);
201 fill_sha1_path(buf
+ len
+ 1, sha1
);
206 * Return the name of the pack or index file with the specified sha1
207 * in its filename. *base and *name are scratch space that must be
208 * provided by the caller. which should be "pack" or "idx".
210 static char *sha1_get_pack_name(const unsigned char *sha1
,
211 char **name
, char **base
, const char *which
)
213 static const char hex
[] = "0123456789abcdef";
218 const char *sha1_file_directory
= get_object_directory();
219 int len
= strlen(sha1_file_directory
);
220 *base
= xmalloc(len
+ 60);
221 sprintf(*base
, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
222 sha1_file_directory
, which
);
223 *name
= *base
+ len
+ 11;
228 for (i
= 0; i
< 20; i
++) {
229 unsigned int val
= *sha1
++;
230 *buf
++ = hex
[val
>> 4];
231 *buf
++ = hex
[val
& 0xf];
237 char *sha1_pack_name(const unsigned char *sha1
)
239 static char *name
, *base
;
241 return sha1_get_pack_name(sha1
, &name
, &base
, "pack");
244 char *sha1_pack_index_name(const unsigned char *sha1
)
246 static char *name
, *base
;
248 return sha1_get_pack_name(sha1
, &name
, &base
, "idx");
251 struct alternate_object_database
*alt_odb_list
;
252 static struct alternate_object_database
**alt_odb_tail
;
255 * Prepare alternate object database registry.
257 * The variable alt_odb_list points at the list of struct
258 * alternate_object_database. The elements on this list come from
259 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
260 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
261 * whose contents is similar to that environment variable but can be
262 * LF separated. Its base points at a statically allocated buffer that
263 * contains "/the/directory/corresponding/to/.git/objects/...", while
264 * its name points just after the slash at the end of ".git/objects/"
265 * in the example above, and has enough space to hold 40-byte hex
266 * SHA1, an extra slash for the first level indirection, and the
269 static int link_alt_odb_entry(const char *entry
, const char *relative_base
,
270 int depth
, const char *normalized_objdir
)
272 struct alternate_object_database
*ent
;
273 struct alternate_object_database
*alt
;
275 struct strbuf pathbuf
= STRBUF_INIT
;
277 if (!is_absolute_path(entry
) && relative_base
) {
278 strbuf_addstr(&pathbuf
, real_path(relative_base
));
279 strbuf_addch(&pathbuf
, '/');
281 strbuf_addstr(&pathbuf
, entry
);
283 normalize_path_copy(pathbuf
.buf
, pathbuf
.buf
);
285 pfxlen
= strlen(pathbuf
.buf
);
288 * The trailing slash after the directory name is given by
289 * this function at the end. Remove duplicates.
291 while (pfxlen
&& pathbuf
.buf
[pfxlen
-1] == '/')
294 entlen
= pfxlen
+ 43; /* '/' + 2 hex + '/' + 38 hex + NUL */
295 ent
= xmalloc(sizeof(*ent
) + entlen
);
296 memcpy(ent
->base
, pathbuf
.buf
, pfxlen
);
297 strbuf_release(&pathbuf
);
299 ent
->name
= ent
->base
+ pfxlen
+ 1;
300 ent
->base
[pfxlen
+ 3] = '/';
301 ent
->base
[pfxlen
] = ent
->base
[entlen
-1] = 0;
303 /* Detect cases where alternate disappeared */
304 if (!is_directory(ent
->base
)) {
305 error("object directory %s does not exist; "
306 "check .git/objects/info/alternates.",
312 /* Prevent the common mistake of listing the same
313 * thing twice, or object directory itself.
315 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
316 if (pfxlen
== alt
->name
- alt
->base
- 1 &&
317 !memcmp(ent
->base
, alt
->base
, pfxlen
)) {
322 if (!strcmp_icase(ent
->base
, normalized_objdir
)) {
327 /* add the alternate entry */
329 alt_odb_tail
= &(ent
->next
);
332 /* recursively add alternates */
333 read_info_alternates(ent
->base
, depth
+ 1);
335 ent
->base
[pfxlen
] = '/';
340 static void link_alt_odb_entries(const char *alt
, int len
, int sep
,
341 const char *relative_base
, int depth
)
343 struct string_list entries
= STRING_LIST_INIT_NODUP
;
346 struct strbuf objdirbuf
= STRBUF_INIT
;
349 error("%s: ignoring alternate object stores, nesting too deep.",
354 strbuf_add_absolute_path(&objdirbuf
, get_object_directory());
355 normalize_path_copy(objdirbuf
.buf
, objdirbuf
.buf
);
357 alt_copy
= xmemdupz(alt
, len
);
358 string_list_split_in_place(&entries
, alt_copy
, sep
, -1);
359 for (i
= 0; i
< entries
.nr
; i
++) {
360 const char *entry
= entries
.items
[i
].string
;
361 if (entry
[0] == '\0' || entry
[0] == '#')
363 if (!is_absolute_path(entry
) && depth
) {
364 error("%s: ignoring relative alternate object store %s",
365 relative_base
, entry
);
367 link_alt_odb_entry(entry
, relative_base
, depth
, objdirbuf
.buf
);
370 string_list_clear(&entries
, 0);
372 strbuf_release(&objdirbuf
);
375 void read_info_alternates(const char * relative_base
, int depth
)
383 path
= xstrfmt("%s/info/alternates", relative_base
);
384 fd
= git_open_noatime(path
);
388 if (fstat(fd
, &st
) || (st
.st_size
== 0)) {
392 mapsz
= xsize_t(st
.st_size
);
393 map
= xmmap(NULL
, mapsz
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
396 link_alt_odb_entries(map
, mapsz
, '\n', relative_base
, depth
);
401 void add_to_alternates_file(const char *reference
)
403 struct lock_file
*lock
= xcalloc(1, sizeof(struct lock_file
));
404 int fd
= hold_lock_file_for_append(lock
, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR
);
405 char *alt
= mkpath("%s\n", reference
);
406 write_or_die(fd
, alt
, strlen(alt
));
407 if (commit_lock_file(lock
))
408 die("could not close alternates file");
410 link_alt_odb_entries(alt
, strlen(alt
), '\n', NULL
, 0);
413 int foreach_alt_odb(alt_odb_fn fn
, void *cb
)
415 struct alternate_object_database
*ent
;
419 for (ent
= alt_odb_list
; ent
; ent
= ent
->next
) {
427 void prepare_alt_odb(void)
434 alt
= getenv(ALTERNATE_DB_ENVIRONMENT
);
437 alt_odb_tail
= &alt_odb_list
;
438 link_alt_odb_entries(alt
, strlen(alt
), PATH_SEP
, NULL
, 0);
440 read_info_alternates(get_object_directory(), 0);
443 /* Returns 1 if we have successfully freshened the file, 0 otherwise. */
444 static int freshen_file(const char *fn
)
447 t
.actime
= t
.modtime
= time(NULL
);
448 return !utime(fn
, &t
);
452 * All of the check_and_freshen functions return 1 if the file exists and was
453 * freshened (if freshening was requested), 0 otherwise. If they return
454 * 0, you should not assume that it is safe to skip a write of the object (it
455 * either does not exist on disk, or has a stale mtime and may be subject to
458 static int check_and_freshen_file(const char *fn
, int freshen
)
460 if (access(fn
, F_OK
))
462 if (freshen
&& !freshen_file(fn
))
467 static int check_and_freshen_local(const unsigned char *sha1
, int freshen
)
469 return check_and_freshen_file(sha1_file_name(sha1
), freshen
);
472 static int check_and_freshen_nonlocal(const unsigned char *sha1
, int freshen
)
474 struct alternate_object_database
*alt
;
476 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
477 fill_sha1_path(alt
->name
, sha1
);
478 if (check_and_freshen_file(alt
->base
, freshen
))
484 static int check_and_freshen(const unsigned char *sha1
, int freshen
)
486 return check_and_freshen_local(sha1
, freshen
) ||
487 check_and_freshen_nonlocal(sha1
, freshen
);
490 int has_loose_object_nonlocal(const unsigned char *sha1
)
492 return check_and_freshen_nonlocal(sha1
, 0);
495 static int has_loose_object(const unsigned char *sha1
)
497 return check_and_freshen(sha1
, 0);
500 static unsigned int pack_used_ctr
;
501 static unsigned int pack_mmap_calls
;
502 static unsigned int peak_pack_open_windows
;
503 static unsigned int pack_open_windows
;
504 static unsigned int pack_open_fds
;
505 static unsigned int pack_max_fds
;
506 static size_t peak_pack_mapped
;
507 static size_t pack_mapped
;
508 struct packed_git
*packed_git
;
510 void pack_report(void)
513 "pack_report: getpagesize() = %10" SZ_FMT
"\n"
514 "pack_report: core.packedGitWindowSize = %10" SZ_FMT
"\n"
515 "pack_report: core.packedGitLimit = %10" SZ_FMT
"\n",
516 sz_fmt(getpagesize()),
517 sz_fmt(packed_git_window_size
),
518 sz_fmt(packed_git_limit
));
520 "pack_report: pack_used_ctr = %10u\n"
521 "pack_report: pack_mmap_calls = %10u\n"
522 "pack_report: pack_open_windows = %10u / %10u\n"
523 "pack_report: pack_mapped = "
524 "%10" SZ_FMT
" / %10" SZ_FMT
"\n",
527 pack_open_windows
, peak_pack_open_windows
,
528 sz_fmt(pack_mapped
), sz_fmt(peak_pack_mapped
));
532 * Open and mmap the index file at path, perform a couple of
533 * consistency checks, then record its information to p. Return 0 on
536 static int check_packed_git_idx(const char *path
, struct packed_git
*p
)
539 struct pack_idx_header
*hdr
;
541 uint32_t version
, nr
, i
, *index
;
542 int fd
= git_open_noatime(path
);
547 if (fstat(fd
, &st
)) {
551 idx_size
= xsize_t(st
.st_size
);
552 if (idx_size
< 4 * 256 + 20 + 20) {
554 return error("index file %s is too small", path
);
556 idx_map
= xmmap(NULL
, idx_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
560 if (hdr
->idx_signature
== htonl(PACK_IDX_SIGNATURE
)) {
561 version
= ntohl(hdr
->idx_version
);
562 if (version
< 2 || version
> 2) {
563 munmap(idx_map
, idx_size
);
564 return error("index file %s is version %"PRIu32
565 " and is not supported by this binary"
566 " (try upgrading GIT to a newer version)",
575 index
+= 2; /* skip index header */
576 for (i
= 0; i
< 256; i
++) {
577 uint32_t n
= ntohl(index
[i
]);
579 munmap(idx_map
, idx_size
);
580 return error("non-monotonic index %s", path
);
588 * - 256 index entries 4 bytes each
589 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
590 * - 20-byte SHA1 of the packfile
591 * - 20-byte SHA1 file checksum
593 if (idx_size
!= 4*256 + nr
* 24 + 20 + 20) {
594 munmap(idx_map
, idx_size
);
595 return error("wrong index v1 file size in %s", path
);
597 } else if (version
== 2) {
600 * - 8 bytes of header
601 * - 256 index entries 4 bytes each
602 * - 20-byte sha1 entry * nr
603 * - 4-byte crc entry * nr
604 * - 4-byte offset entry * nr
605 * - 20-byte SHA1 of the packfile
606 * - 20-byte SHA1 file checksum
607 * And after the 4-byte offset table might be a
608 * variable sized table containing 8-byte entries
609 * for offsets larger than 2^31.
611 unsigned long min_size
= 8 + 4*256 + nr
*(20 + 4 + 4) + 20 + 20;
612 unsigned long max_size
= min_size
;
614 max_size
+= (nr
- 1)*8;
615 if (idx_size
< min_size
|| idx_size
> max_size
) {
616 munmap(idx_map
, idx_size
);
617 return error("wrong index v2 file size in %s", path
);
619 if (idx_size
!= min_size
&&
621 * make sure we can deal with large pack offsets.
622 * 31-bit signed offset won't be enough, neither
623 * 32-bit unsigned one will be.
625 (sizeof(off_t
) <= 4)) {
626 munmap(idx_map
, idx_size
);
627 return error("pack too large for current definition of off_t in %s", path
);
631 p
->index_version
= version
;
632 p
->index_data
= idx_map
;
633 p
->index_size
= idx_size
;
638 int open_pack_index(struct packed_git
*p
)
646 idx_name
= xstrdup(p
->pack_name
);
647 strcpy(idx_name
+ strlen(idx_name
) - strlen(".pack"), ".idx");
648 ret
= check_packed_git_idx(idx_name
, p
);
653 static void scan_windows(struct packed_git
*p
,
654 struct packed_git
**lru_p
,
655 struct pack_window
**lru_w
,
656 struct pack_window
**lru_l
)
658 struct pack_window
*w
, *w_l
;
660 for (w_l
= NULL
, w
= p
->windows
; w
; w
= w
->next
) {
662 if (!*lru_w
|| w
->last_used
< (*lru_w
)->last_used
) {
672 static int unuse_one_window(struct packed_git
*current
)
674 struct packed_git
*p
, *lru_p
= NULL
;
675 struct pack_window
*lru_w
= NULL
, *lru_l
= NULL
;
678 scan_windows(current
, &lru_p
, &lru_w
, &lru_l
);
679 for (p
= packed_git
; p
; p
= p
->next
)
680 scan_windows(p
, &lru_p
, &lru_w
, &lru_l
);
682 munmap(lru_w
->base
, lru_w
->len
);
683 pack_mapped
-= lru_w
->len
;
685 lru_l
->next
= lru_w
->next
;
687 lru_p
->windows
= lru_w
->next
;
695 void release_pack_memory(size_t need
)
697 size_t cur
= pack_mapped
;
698 while (need
>= (cur
- pack_mapped
) && unuse_one_window(NULL
))
702 static void mmap_limit_check(size_t length
)
704 static size_t limit
= 0;
706 limit
= git_env_ulong("GIT_MMAP_LIMIT", 0);
711 die("attempting to mmap %"PRIuMAX
" over limit %"PRIuMAX
,
712 (uintmax_t)length
, (uintmax_t)limit
);
715 void *xmmap_gently(void *start
, size_t length
,
716 int prot
, int flags
, int fd
, off_t offset
)
720 mmap_limit_check(length
);
721 ret
= mmap(start
, length
, prot
, flags
, fd
, offset
);
722 if (ret
== MAP_FAILED
) {
725 release_pack_memory(length
);
726 ret
= mmap(start
, length
, prot
, flags
, fd
, offset
);
731 void *xmmap(void *start
, size_t length
,
732 int prot
, int flags
, int fd
, off_t offset
)
734 void *ret
= xmmap_gently(start
, length
, prot
, flags
, fd
, offset
);
735 if (ret
== MAP_FAILED
)
736 die_errno("mmap failed");
740 void close_pack_windows(struct packed_git
*p
)
743 struct pack_window
*w
= p
->windows
;
746 die("pack '%s' still has open windows to it",
748 munmap(w
->base
, w
->len
);
749 pack_mapped
-= w
->len
;
751 p
->windows
= w
->next
;
756 static int close_pack_fd(struct packed_git
*p
)
768 static void close_pack(struct packed_git
*p
)
770 close_pack_windows(p
);
775 void close_all_packs(void)
777 struct packed_git
*p
;
779 for (p
= packed_git
; p
; p
= p
->next
)
781 die("BUG! Want to close pack marked 'do-not-close'");
788 * The LRU pack is the one with the oldest MRU window, preferring packs
789 * with no used windows, or the oldest mtime if it has no windows allocated.
791 static void find_lru_pack(struct packed_git
*p
, struct packed_git
**lru_p
, struct pack_window
**mru_w
, int *accept_windows_inuse
)
793 struct pack_window
*w
, *this_mru_w
;
794 int has_windows_inuse
= 0;
797 * Reject this pack if it has windows and the previously selected
798 * one does not. If this pack does not have windows, reject
799 * it if the pack file is newer than the previously selected one.
801 if (*lru_p
&& !*mru_w
&& (p
->windows
|| p
->mtime
> (*lru_p
)->mtime
))
804 for (w
= this_mru_w
= p
->windows
; w
; w
= w
->next
) {
806 * Reject this pack if any of its windows are in use,
807 * but the previously selected pack did not have any
808 * inuse windows. Otherwise, record that this pack
809 * has windows in use.
812 if (*accept_windows_inuse
)
813 has_windows_inuse
= 1;
818 if (w
->last_used
> this_mru_w
->last_used
)
822 * Reject this pack if it has windows that have been
823 * used more recently than the previously selected pack.
824 * If the previously selected pack had windows inuse and
825 * we have not encountered a window in this pack that is
826 * inuse, skip this check since we prefer a pack with no
827 * inuse windows to one that has inuse windows.
829 if (*mru_w
&& *accept_windows_inuse
== has_windows_inuse
&&
830 this_mru_w
->last_used
> (*mru_w
)->last_used
)
839 *accept_windows_inuse
= has_windows_inuse
;
842 static int close_one_pack(void)
844 struct packed_git
*p
, *lru_p
= NULL
;
845 struct pack_window
*mru_w
= NULL
;
846 int accept_windows_inuse
= 1;
848 for (p
= packed_git
; p
; p
= p
->next
) {
849 if (p
->pack_fd
== -1)
851 find_lru_pack(p
, &lru_p
, &mru_w
, &accept_windows_inuse
);
855 return close_pack_fd(lru_p
);
860 void unuse_pack(struct pack_window
**w_cursor
)
862 struct pack_window
*w
= *w_cursor
;
869 void close_pack_index(struct packed_git
*p
)
872 munmap((void *)p
->index_data
, p
->index_size
);
873 p
->index_data
= NULL
;
878 * This is used by git-repack in case a newly created pack happens to
879 * contain the same set of objects as an existing one. In that case
880 * the resulting file might be different even if its name would be the
881 * same. It is best to close any reference to the old pack before it is
882 * replaced on disk. Of course no index pointers or windows for given pack
883 * must subsist at this point. If ever objects from this pack are requested
884 * again, the new version of the pack will be reinitialized through
885 * reprepare_packed_git().
887 void free_pack_by_name(const char *pack_name
)
889 struct packed_git
*p
, **pp
= &packed_git
;
893 if (strcmp(pack_name
, p
->pack_name
) == 0) {
894 clear_delta_base_cache();
896 free(p
->bad_object_sha1
);
898 if (last_found_pack
== p
)
899 last_found_pack
= NULL
;
907 static unsigned int get_max_fd_limit(void)
913 if (!getrlimit(RLIMIT_NOFILE
, &lim
))
920 long open_max
= sysconf(_SC_OPEN_MAX
);
924 * Otherwise, we got -1 for one of the two
927 * (1) sysconf() did not understand _SC_OPEN_MAX
928 * and signaled an error with -1; or
929 * (2) sysconf() said there is no limit.
931 * We _could_ clear errno before calling sysconf() to
932 * tell these two cases apart and return a huge number
933 * in the latter case to let the caller cap it to a
934 * value that is not so selfish, but letting the
935 * fallback OPEN_MAX codepath take care of these cases
944 return 1; /* see the caller ;-) */
949 * Do not call this directly as this leaks p->pack_fd on error return;
950 * call open_packed_git() instead.
952 static int open_packed_git_1(struct packed_git
*p
)
955 struct pack_header hdr
;
956 unsigned char sha1
[20];
957 unsigned char *idx_sha1
;
960 if (!p
->index_data
&& open_pack_index(p
))
961 return error("packfile %s index unavailable", p
->pack_name
);
964 unsigned int max_fds
= get_max_fd_limit();
966 /* Save 3 for stdin/stdout/stderr, 22 for work */
968 pack_max_fds
= max_fds
- 25;
973 while (pack_max_fds
<= pack_open_fds
&& close_one_pack())
976 p
->pack_fd
= git_open_noatime(p
->pack_name
);
977 if (p
->pack_fd
< 0 || fstat(p
->pack_fd
, &st
))
981 /* If we created the struct before we had the pack we lack size. */
983 if (!S_ISREG(st
.st_mode
))
984 return error("packfile %s not a regular file", p
->pack_name
);
985 p
->pack_size
= st
.st_size
;
986 } else if (p
->pack_size
!= st
.st_size
)
987 return error("packfile %s size changed", p
->pack_name
);
989 /* We leave these file descriptors open with sliding mmap;
990 * there is no point keeping them open across exec(), though.
992 fd_flag
= fcntl(p
->pack_fd
, F_GETFD
, 0);
994 return error("cannot determine file descriptor flags");
995 fd_flag
|= FD_CLOEXEC
;
996 if (fcntl(p
->pack_fd
, F_SETFD
, fd_flag
) == -1)
997 return error("cannot set FD_CLOEXEC");
999 /* Verify we recognize this pack file format. */
1000 if (read_in_full(p
->pack_fd
, &hdr
, sizeof(hdr
)) != sizeof(hdr
))
1001 return error("file %s is far too short to be a packfile", p
->pack_name
);
1002 if (hdr
.hdr_signature
!= htonl(PACK_SIGNATURE
))
1003 return error("file %s is not a GIT packfile", p
->pack_name
);
1004 if (!pack_version_ok(hdr
.hdr_version
))
1005 return error("packfile %s is version %"PRIu32
" and not"
1006 " supported (try upgrading GIT to a newer version)",
1007 p
->pack_name
, ntohl(hdr
.hdr_version
));
1009 /* Verify the pack matches its index. */
1010 if (p
->num_objects
!= ntohl(hdr
.hdr_entries
))
1011 return error("packfile %s claims to have %"PRIu32
" objects"
1012 " while index indicates %"PRIu32
" objects",
1013 p
->pack_name
, ntohl(hdr
.hdr_entries
),
1015 if (lseek(p
->pack_fd
, p
->pack_size
- sizeof(sha1
), SEEK_SET
) == -1)
1016 return error("end of packfile %s is unavailable", p
->pack_name
);
1017 if (read_in_full(p
->pack_fd
, sha1
, sizeof(sha1
)) != sizeof(sha1
))
1018 return error("packfile %s signature is unavailable", p
->pack_name
);
1019 idx_sha1
= ((unsigned char *)p
->index_data
) + p
->index_size
- 40;
1020 if (hashcmp(sha1
, idx_sha1
))
1021 return error("packfile %s does not match index", p
->pack_name
);
1025 static int open_packed_git(struct packed_git
*p
)
1027 if (!open_packed_git_1(p
))
1033 static int in_window(struct pack_window
*win
, off_t offset
)
1035 /* We must promise at least 20 bytes (one hash) after the
1036 * offset is available from this window, otherwise the offset
1037 * is not actually in this window and a different window (which
1038 * has that one hash excess) must be used. This is to support
1039 * the object header and delta base parsing routines below.
1041 off_t win_off
= win
->offset
;
1042 return win_off
<= offset
1043 && (offset
+ 20) <= (win_off
+ win
->len
);
1046 unsigned char *use_pack(struct packed_git
*p
,
1047 struct pack_window
**w_cursor
,
1049 unsigned long *left
)
1051 struct pack_window
*win
= *w_cursor
;
1053 /* Since packfiles end in a hash of their content and it's
1054 * pointless to ask for an offset into the middle of that
1055 * hash, and the in_window function above wouldn't match
1056 * don't allow an offset too close to the end of the file.
1058 if (!p
->pack_size
&& p
->pack_fd
== -1 && open_packed_git(p
))
1059 die("packfile %s cannot be accessed", p
->pack_name
);
1060 if (offset
> (p
->pack_size
- 20))
1061 die("offset beyond end of packfile (truncated pack?)");
1063 if (!win
|| !in_window(win
, offset
)) {
1066 for (win
= p
->windows
; win
; win
= win
->next
) {
1067 if (in_window(win
, offset
))
1071 size_t window_align
= packed_git_window_size
/ 2;
1074 if (p
->pack_fd
== -1 && open_packed_git(p
))
1075 die("packfile %s cannot be accessed", p
->pack_name
);
1077 win
= xcalloc(1, sizeof(*win
));
1078 win
->offset
= (offset
/ window_align
) * window_align
;
1079 len
= p
->pack_size
- win
->offset
;
1080 if (len
> packed_git_window_size
)
1081 len
= packed_git_window_size
;
1082 win
->len
= (size_t)len
;
1083 pack_mapped
+= win
->len
;
1084 while (packed_git_limit
< pack_mapped
1085 && unuse_one_window(p
))
1087 win
->base
= xmmap(NULL
, win
->len
,
1088 PROT_READ
, MAP_PRIVATE
,
1089 p
->pack_fd
, win
->offset
);
1090 if (win
->base
== MAP_FAILED
)
1091 die("packfile %s cannot be mapped: %s",
1094 if (!win
->offset
&& win
->len
== p
->pack_size
1095 && !p
->do_not_close
)
1098 pack_open_windows
++;
1099 if (pack_mapped
> peak_pack_mapped
)
1100 peak_pack_mapped
= pack_mapped
;
1101 if (pack_open_windows
> peak_pack_open_windows
)
1102 peak_pack_open_windows
= pack_open_windows
;
1103 win
->next
= p
->windows
;
1107 if (win
!= *w_cursor
) {
1108 win
->last_used
= pack_used_ctr
++;
1112 offset
-= win
->offset
;
1114 *left
= win
->len
- xsize_t(offset
);
1115 return win
->base
+ offset
;
1118 static struct packed_git
*alloc_packed_git(int extra
)
1120 struct packed_git
*p
= xmalloc(sizeof(*p
) + extra
);
1121 memset(p
, 0, sizeof(*p
));
1126 static void try_to_free_pack_memory(size_t size
)
1128 release_pack_memory(size
);
1131 struct packed_git
*add_packed_git(const char *path
, int path_len
, int local
)
1133 static int have_set_try_to_free_routine
;
1135 struct packed_git
*p
= alloc_packed_git(path_len
+ 2);
1137 if (!have_set_try_to_free_routine
) {
1138 have_set_try_to_free_routine
= 1;
1139 set_try_to_free_routine(try_to_free_pack_memory
);
1143 * Make sure a corresponding .pack file exists and that
1144 * the index looks sane.
1146 path_len
-= strlen(".idx");
1151 memcpy(p
->pack_name
, path
, path_len
);
1153 strcpy(p
->pack_name
+ path_len
, ".keep");
1154 if (!access(p
->pack_name
, F_OK
))
1157 strcpy(p
->pack_name
+ path_len
, ".pack");
1158 if (stat(p
->pack_name
, &st
) || !S_ISREG(st
.st_mode
)) {
1163 /* ok, it looks sane as far as we can check without
1164 * actually mapping the pack file.
1166 p
->pack_size
= st
.st_size
;
1167 p
->pack_local
= local
;
1168 p
->mtime
= st
.st_mtime
;
1169 if (path_len
< 40 || get_sha1_hex(path
+ path_len
- 40, p
->sha1
))
1174 struct packed_git
*parse_pack_index(unsigned char *sha1
, const char *idx_path
)
1176 const char *path
= sha1_pack_name(sha1
);
1177 struct packed_git
*p
= alloc_packed_git(strlen(path
) + 1);
1179 strcpy(p
->pack_name
, path
);
1180 hashcpy(p
->sha1
, sha1
);
1181 if (check_packed_git_idx(idx_path
, p
)) {
1189 void install_packed_git(struct packed_git
*pack
)
1191 if (pack
->pack_fd
!= -1)
1194 pack
->next
= packed_git
;
1198 void (*report_garbage
)(const char *desc
, const char *path
);
1200 static void report_helper(const struct string_list
*list
,
1201 int seen_bits
, int first
, int last
)
1204 switch (seen_bits
) {
1206 msg
= "no corresponding .idx or .pack";
1209 msg
= "no corresponding .idx";
1212 msg
= "no corresponding .pack";
1217 for (; first
< last
; first
++)
1218 report_garbage(msg
, list
->items
[first
].string
);
1221 static void report_pack_garbage(struct string_list
*list
)
1223 int i
, baselen
= -1, first
= 0, seen_bits
= 0;
1225 if (!report_garbage
)
1228 string_list_sort(list
);
1230 for (i
= 0; i
< list
->nr
; i
++) {
1231 const char *path
= list
->items
[i
].string
;
1232 if (baselen
!= -1 &&
1233 strncmp(path
, list
->items
[first
].string
, baselen
)) {
1234 report_helper(list
, seen_bits
, first
, i
);
1238 if (baselen
== -1) {
1239 const char *dot
= strrchr(path
, '.');
1241 report_garbage("garbage found", path
);
1244 baselen
= dot
- path
+ 1;
1247 if (!strcmp(path
+ baselen
, "pack"))
1249 else if (!strcmp(path
+ baselen
, "idx"))
1252 report_helper(list
, seen_bits
, first
, list
->nr
);
1255 static void prepare_packed_git_one(char *objdir
, int local
)
1257 struct strbuf path
= STRBUF_INIT
;
1261 struct string_list garbage
= STRING_LIST_INIT_DUP
;
1263 strbuf_addstr(&path
, objdir
);
1264 strbuf_addstr(&path
, "/pack");
1265 dir
= opendir(path
.buf
);
1267 if (errno
!= ENOENT
)
1268 error("unable to open object pack directory: %s: %s",
1269 path
.buf
, strerror(errno
));
1270 strbuf_release(&path
);
1273 strbuf_addch(&path
, '/');
1274 dirnamelen
= path
.len
;
1275 while ((de
= readdir(dir
)) != NULL
) {
1276 struct packed_git
*p
;
1279 if (is_dot_or_dotdot(de
->d_name
))
1282 strbuf_setlen(&path
, dirnamelen
);
1283 strbuf_addstr(&path
, de
->d_name
);
1285 base_len
= path
.len
;
1286 if (strip_suffix_mem(path
.buf
, &base_len
, ".idx")) {
1287 /* Don't reopen a pack we already have. */
1288 for (p
= packed_git
; p
; p
= p
->next
) {
1290 if (strip_suffix(p
->pack_name
, ".pack", &len
) &&
1292 !memcmp(p
->pack_name
, path
.buf
, len
))
1297 * See if it really is a valid .idx file with
1298 * corresponding .pack file that we can map.
1300 (p
= add_packed_git(path
.buf
, path
.len
, local
)) != NULL
)
1301 install_packed_git(p
);
1304 if (!report_garbage
)
1307 if (ends_with(de
->d_name
, ".idx") ||
1308 ends_with(de
->d_name
, ".pack") ||
1309 ends_with(de
->d_name
, ".bitmap") ||
1310 ends_with(de
->d_name
, ".keep"))
1311 string_list_append(&garbage
, path
.buf
);
1313 report_garbage("garbage found", path
.buf
);
1316 report_pack_garbage(&garbage
);
1317 string_list_clear(&garbage
, 0);
1318 strbuf_release(&path
);
1321 static int sort_pack(const void *a_
, const void *b_
)
1323 struct packed_git
*a
= *((struct packed_git
**)a_
);
1324 struct packed_git
*b
= *((struct packed_git
**)b_
);
1328 * Local packs tend to contain objects specific to our
1329 * variant of the project than remote ones. In addition,
1330 * remote ones could be on a network mounted filesystem.
1331 * Favor local ones for these reasons.
1333 st
= a
->pack_local
- b
->pack_local
;
1338 * Younger packs tend to contain more recent objects,
1339 * and more recent objects tend to get accessed more
1342 if (a
->mtime
< b
->mtime
)
1344 else if (a
->mtime
== b
->mtime
)
1349 static void rearrange_packed_git(void)
1351 struct packed_git
**ary
, *p
;
1354 for (n
= 0, p
= packed_git
; p
; p
= p
->next
)
1359 /* prepare an array of packed_git for easier sorting */
1360 ary
= xcalloc(n
, sizeof(struct packed_git
*));
1361 for (n
= 0, p
= packed_git
; p
; p
= p
->next
)
1364 qsort(ary
, n
, sizeof(struct packed_git
*), sort_pack
);
1366 /* link them back again */
1367 for (i
= 0; i
< n
- 1; i
++)
1368 ary
[i
]->next
= ary
[i
+ 1];
1369 ary
[n
- 1]->next
= NULL
;
1370 packed_git
= ary
[0];
1375 static int prepare_packed_git_run_once
= 0;
1376 void prepare_packed_git(void)
1378 struct alternate_object_database
*alt
;
1380 if (prepare_packed_git_run_once
)
1382 prepare_packed_git_one(get_object_directory(), 1);
1384 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
1386 prepare_packed_git_one(alt
->base
, 0);
1387 alt
->name
[-1] = '/';
1389 rearrange_packed_git();
1390 prepare_packed_git_run_once
= 1;
1393 void reprepare_packed_git(void)
1395 prepare_packed_git_run_once
= 0;
1396 prepare_packed_git();
1399 static void mark_bad_packed_object(struct packed_git
*p
,
1400 const unsigned char *sha1
)
1403 for (i
= 0; i
< p
->num_bad_objects
; i
++)
1404 if (!hashcmp(sha1
, p
->bad_object_sha1
+ 20 * i
))
1406 p
->bad_object_sha1
= xrealloc(p
->bad_object_sha1
, 20 * (p
->num_bad_objects
+ 1));
1407 hashcpy(p
->bad_object_sha1
+ 20 * p
->num_bad_objects
, sha1
);
1408 p
->num_bad_objects
++;
1411 static const struct packed_git
*has_packed_and_bad(const unsigned char *sha1
)
1413 struct packed_git
*p
;
1416 for (p
= packed_git
; p
; p
= p
->next
)
1417 for (i
= 0; i
< p
->num_bad_objects
; i
++)
1418 if (!hashcmp(sha1
, p
->bad_object_sha1
+ 20 * i
))
1424 * With an in-core object data in "map", rehash it to make sure the
1425 * object name actually matches "sha1" to detect object corruption.
1426 * With "map" == NULL, try reading the object named with "sha1" using
1427 * the streaming interface and rehash it to do the same.
1429 int check_sha1_signature(const unsigned char *sha1
, void *map
,
1430 unsigned long size
, const char *type
)
1432 unsigned char real_sha1
[20];
1433 enum object_type obj_type
;
1434 struct git_istream
*st
;
1440 hash_sha1_file(map
, size
, type
, real_sha1
);
1441 return hashcmp(sha1
, real_sha1
) ? -1 : 0;
1444 st
= open_istream(sha1
, &obj_type
, &size
, NULL
);
1448 /* Generate the header */
1449 hdrlen
= sprintf(hdr
, "%s %lu", typename(obj_type
), size
) + 1;
1453 git_SHA1_Update(&c
, hdr
, hdrlen
);
1455 char buf
[1024 * 16];
1456 ssize_t readlen
= read_istream(st
, buf
, sizeof(buf
));
1464 git_SHA1_Update(&c
, buf
, readlen
);
1466 git_SHA1_Final(real_sha1
, &c
);
1468 return hashcmp(sha1
, real_sha1
) ? -1 : 0;
1471 int git_open_noatime(const char *name
)
1473 static int sha1_file_open_flag
= O_NOATIME
;
1476 int fd
= open(name
, O_RDONLY
| sha1_file_open_flag
);
1480 /* Might the failure be due to O_NOATIME? */
1481 if (errno
!= ENOENT
&& sha1_file_open_flag
) {
1482 sha1_file_open_flag
= 0;
1490 static int stat_sha1_file(const unsigned char *sha1
, struct stat
*st
)
1492 struct alternate_object_database
*alt
;
1494 if (!lstat(sha1_file_name(sha1
), st
))
1499 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
1500 fill_sha1_path(alt
->name
, sha1
);
1501 if (!lstat(alt
->base
, st
))
1508 static int open_sha1_file(const unsigned char *sha1
)
1511 struct alternate_object_database
*alt
;
1512 int most_interesting_errno
;
1514 fd
= git_open_noatime(sha1_file_name(sha1
));
1517 most_interesting_errno
= errno
;
1520 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
1521 fill_sha1_path(alt
->name
, sha1
);
1522 fd
= git_open_noatime(alt
->base
);
1525 if (most_interesting_errno
== ENOENT
)
1526 most_interesting_errno
= errno
;
1528 errno
= most_interesting_errno
;
1532 void *map_sha1_file(const unsigned char *sha1
, unsigned long *size
)
1537 fd
= open_sha1_file(sha1
);
1542 if (!fstat(fd
, &st
)) {
1543 *size
= xsize_t(st
.st_size
);
1545 /* mmap() is forbidden on empty files */
1546 error("object file %s is empty", sha1_file_name(sha1
));
1549 map
= xmmap(NULL
, *size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
1556 unsigned long unpack_object_header_buffer(const unsigned char *buf
,
1557 unsigned long len
, enum object_type
*type
, unsigned long *sizep
)
1560 unsigned long size
, c
;
1561 unsigned long used
= 0;
1564 *type
= (c
>> 4) & 7;
1568 if (len
<= used
|| bitsizeof(long) <= shift
) {
1569 error("bad object header");
1574 size
+= (c
& 0x7f) << shift
;
1581 int unpack_sha1_header(git_zstream
*stream
, unsigned char *map
, unsigned long mapsize
, void *buffer
, unsigned long bufsiz
)
1583 /* Get the data stream */
1584 memset(stream
, 0, sizeof(*stream
));
1585 stream
->next_in
= map
;
1586 stream
->avail_in
= mapsize
;
1587 stream
->next_out
= buffer
;
1588 stream
->avail_out
= bufsiz
;
1590 git_inflate_init(stream
);
1591 return git_inflate(stream
, 0);
1594 static void *unpack_sha1_rest(git_zstream
*stream
, void *buffer
, unsigned long size
, const unsigned char *sha1
)
1596 int bytes
= strlen(buffer
) + 1;
1597 unsigned char *buf
= xmallocz(size
);
1601 n
= stream
->total_out
- bytes
;
1604 memcpy(buf
, (char *) buffer
+ bytes
, n
);
1606 if (bytes
<= size
) {
1608 * The above condition must be (bytes <= size), not
1609 * (bytes < size). In other words, even though we
1610 * expect no more output and set avail_out to zero,
1611 * the input zlib stream may have bytes that express
1612 * "this concludes the stream", and we *do* want to
1615 * Otherwise we would not be able to test that we
1616 * consumed all the input to reach the expected size;
1617 * we also want to check that zlib tells us that all
1618 * went well with status == Z_STREAM_END at the end.
1620 stream
->next_out
= buf
+ bytes
;
1621 stream
->avail_out
= size
- bytes
;
1622 while (status
== Z_OK
)
1623 status
= git_inflate(stream
, Z_FINISH
);
1625 if (status
== Z_STREAM_END
&& !stream
->avail_in
) {
1626 git_inflate_end(stream
);
1631 error("corrupt loose object '%s'", sha1_to_hex(sha1
));
1632 else if (stream
->avail_in
)
1633 error("garbage at end of loose object '%s'",
1640 * We used to just use "sscanf()", but that's actually way
1641 * too permissive for what we want to check. So do an anal
1642 * object header parse by hand.
1644 int parse_sha1_header(const char *hdr
, unsigned long *sizep
)
1651 * The type can be at most ten bytes (including the
1652 * terminating '\0' that we add), and is followed by
1661 if (i
>= sizeof(type
))
1667 * The length must follow immediately, and be in canonical
1668 * decimal format (ie "010" is not valid).
1670 size
= *hdr
++ - '0';
1675 unsigned long c
= *hdr
- '0';
1679 size
= size
* 10 + c
;
1685 * The length must be followed by a zero byte
1687 return *hdr
? -1 : type_from_string(type
);
1690 static void *unpack_sha1_file(void *map
, unsigned long mapsize
, enum object_type
*type
, unsigned long *size
, const unsigned char *sha1
)
1696 ret
= unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
));
1697 if (ret
< Z_OK
|| (*type
= parse_sha1_header(hdr
, size
)) < 0)
1700 return unpack_sha1_rest(&stream
, hdr
, *size
, sha1
);
1703 unsigned long get_size_from_delta(struct packed_git
*p
,
1704 struct pack_window
**w_curs
,
1707 const unsigned char *data
;
1708 unsigned char delta_head
[20], *in
;
1712 memset(&stream
, 0, sizeof(stream
));
1713 stream
.next_out
= delta_head
;
1714 stream
.avail_out
= sizeof(delta_head
);
1716 git_inflate_init(&stream
);
1718 in
= use_pack(p
, w_curs
, curpos
, &stream
.avail_in
);
1719 stream
.next_in
= in
;
1720 st
= git_inflate(&stream
, Z_FINISH
);
1721 curpos
+= stream
.next_in
- in
;
1722 } while ((st
== Z_OK
|| st
== Z_BUF_ERROR
) &&
1723 stream
.total_out
< sizeof(delta_head
));
1724 git_inflate_end(&stream
);
1725 if ((st
!= Z_STREAM_END
) && stream
.total_out
!= sizeof(delta_head
)) {
1726 error("delta data unpack-initial failed");
1730 /* Examine the initial part of the delta to figure out
1735 /* ignore base size */
1736 get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
1738 /* Read the result size */
1739 return get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
1742 static off_t
get_delta_base(struct packed_git
*p
,
1743 struct pack_window
**w_curs
,
1745 enum object_type type
,
1746 off_t delta_obj_offset
)
1748 unsigned char *base_info
= use_pack(p
, w_curs
, *curpos
, NULL
);
1751 /* use_pack() assured us we have [base_info, base_info + 20)
1752 * as a range that we can look at without walking off the
1753 * end of the mapped window. Its actually the hash size
1754 * that is assured. An OFS_DELTA longer than the hash size
1755 * is stupid, as then a REF_DELTA would be smaller to store.
1757 if (type
== OBJ_OFS_DELTA
) {
1759 unsigned char c
= base_info
[used
++];
1760 base_offset
= c
& 127;
1763 if (!base_offset
|| MSB(base_offset
, 7))
1764 return 0; /* overflow */
1765 c
= base_info
[used
++];
1766 base_offset
= (base_offset
<< 7) + (c
& 127);
1768 base_offset
= delta_obj_offset
- base_offset
;
1769 if (base_offset
<= 0 || base_offset
>= delta_obj_offset
)
1770 return 0; /* out of bound */
1772 } else if (type
== OBJ_REF_DELTA
) {
1773 /* The base entry _must_ be in the same pack */
1774 base_offset
= find_pack_entry_one(base_info
, p
);
1777 die("I am totally screwed");
1782 * Like get_delta_base above, but we return the sha1 instead of the pack
1783 * offset. This means it is cheaper for REF deltas (we do not have to do
1784 * the final object lookup), but more expensive for OFS deltas (we
1785 * have to load the revidx to convert the offset back into a sha1).
1787 static const unsigned char *get_delta_base_sha1(struct packed_git
*p
,
1788 struct pack_window
**w_curs
,
1790 enum object_type type
,
1791 off_t delta_obj_offset
)
1793 if (type
== OBJ_REF_DELTA
) {
1794 unsigned char *base
= use_pack(p
, w_curs
, curpos
, NULL
);
1796 } else if (type
== OBJ_OFS_DELTA
) {
1797 struct revindex_entry
*revidx
;
1798 off_t base_offset
= get_delta_base(p
, w_curs
, &curpos
,
1799 type
, delta_obj_offset
);
1804 revidx
= find_pack_revindex(p
, base_offset
);
1808 return nth_packed_object_sha1(p
, revidx
->nr
);
1813 int unpack_object_header(struct packed_git
*p
,
1814 struct pack_window
**w_curs
,
1816 unsigned long *sizep
)
1818 unsigned char *base
;
1821 enum object_type type
;
1823 /* use_pack() assures us we have [base, base + 20) available
1824 * as a range that we can look at. (Its actually the hash
1825 * size that is assured.) With our object header encoding
1826 * the maximum deflated object size is 2^137, which is just
1827 * insane, so we know won't exceed what we have been given.
1829 base
= use_pack(p
, w_curs
, *curpos
, &left
);
1830 used
= unpack_object_header_buffer(base
, left
, &type
, sizep
);
1839 static int retry_bad_packed_offset(struct packed_git
*p
, off_t obj_offset
)
1842 struct revindex_entry
*revidx
;
1843 const unsigned char *sha1
;
1844 revidx
= find_pack_revindex(p
, obj_offset
);
1847 sha1
= nth_packed_object_sha1(p
, revidx
->nr
);
1848 mark_bad_packed_object(p
, sha1
);
1849 type
= sha1_object_info(sha1
, NULL
);
1850 if (type
<= OBJ_NONE
)
1855 #define POI_STACK_PREALLOC 64
1857 static enum object_type
packed_to_object_type(struct packed_git
*p
,
1859 enum object_type type
,
1860 struct pack_window
**w_curs
,
1863 off_t small_poi_stack
[POI_STACK_PREALLOC
];
1864 off_t
*poi_stack
= small_poi_stack
;
1865 int poi_stack_nr
= 0, poi_stack_alloc
= POI_STACK_PREALLOC
;
1867 while (type
== OBJ_OFS_DELTA
|| type
== OBJ_REF_DELTA
) {
1870 /* Push the object we're going to leave behind */
1871 if (poi_stack_nr
>= poi_stack_alloc
&& poi_stack
== small_poi_stack
) {
1872 poi_stack_alloc
= alloc_nr(poi_stack_nr
);
1873 poi_stack
= xmalloc(sizeof(off_t
)*poi_stack_alloc
);
1874 memcpy(poi_stack
, small_poi_stack
, sizeof(off_t
)*poi_stack_nr
);
1876 ALLOC_GROW(poi_stack
, poi_stack_nr
+1, poi_stack_alloc
);
1878 poi_stack
[poi_stack_nr
++] = obj_offset
;
1879 /* If parsing the base offset fails, just unwind */
1880 base_offset
= get_delta_base(p
, w_curs
, &curpos
, type
, obj_offset
);
1883 curpos
= obj_offset
= base_offset
;
1884 type
= unpack_object_header(p
, w_curs
, &curpos
, &size
);
1885 if (type
<= OBJ_NONE
) {
1886 /* If getting the base itself fails, we first
1887 * retry the base, otherwise unwind */
1888 type
= retry_bad_packed_offset(p
, base_offset
);
1889 if (type
> OBJ_NONE
)
1903 error("unknown object type %i at offset %"PRIuMAX
" in %s",
1904 type
, (uintmax_t)obj_offset
, p
->pack_name
);
1909 if (poi_stack
!= small_poi_stack
)
1914 while (poi_stack_nr
) {
1915 obj_offset
= poi_stack
[--poi_stack_nr
];
1916 type
= retry_bad_packed_offset(p
, obj_offset
);
1917 if (type
> OBJ_NONE
)
1924 static int packed_object_info(struct packed_git
*p
, off_t obj_offset
,
1925 struct object_info
*oi
)
1927 struct pack_window
*w_curs
= NULL
;
1929 off_t curpos
= obj_offset
;
1930 enum object_type type
;
1933 * We always get the representation type, but only convert it to
1934 * a "real" type later if the caller is interested.
1936 type
= unpack_object_header(p
, &w_curs
, &curpos
, &size
);
1939 if (type
== OBJ_OFS_DELTA
|| type
== OBJ_REF_DELTA
) {
1940 off_t tmp_pos
= curpos
;
1941 off_t base_offset
= get_delta_base(p
, &w_curs
, &tmp_pos
,
1947 *oi
->sizep
= get_size_from_delta(p
, &w_curs
, tmp_pos
);
1948 if (*oi
->sizep
== 0) {
1957 if (oi
->disk_sizep
) {
1958 struct revindex_entry
*revidx
= find_pack_revindex(p
, obj_offset
);
1959 *oi
->disk_sizep
= revidx
[1].offset
- obj_offset
;
1963 *oi
->typep
= packed_to_object_type(p
, obj_offset
, type
, &w_curs
, curpos
);
1964 if (*oi
->typep
< 0) {
1970 if (oi
->delta_base_sha1
) {
1971 if (type
== OBJ_OFS_DELTA
|| type
== OBJ_REF_DELTA
) {
1972 const unsigned char *base
;
1974 base
= get_delta_base_sha1(p
, &w_curs
, curpos
,
1981 hashcpy(oi
->delta_base_sha1
, base
);
1983 hashclr(oi
->delta_base_sha1
);
1987 unuse_pack(&w_curs
);
1991 static void *unpack_compressed_entry(struct packed_git
*p
,
1992 struct pack_window
**w_curs
,
1998 unsigned char *buffer
, *in
;
2000 buffer
= xmallocz_gently(size
);
2003 memset(&stream
, 0, sizeof(stream
));
2004 stream
.next_out
= buffer
;
2005 stream
.avail_out
= size
+ 1;
2007 git_inflate_init(&stream
);
2009 in
= use_pack(p
, w_curs
, curpos
, &stream
.avail_in
);
2010 stream
.next_in
= in
;
2011 st
= git_inflate(&stream
, Z_FINISH
);
2012 if (!stream
.avail_out
)
2013 break; /* the payload is larger than it should be */
2014 curpos
+= stream
.next_in
- in
;
2015 } while (st
== Z_OK
|| st
== Z_BUF_ERROR
);
2016 git_inflate_end(&stream
);
2017 if ((st
!= Z_STREAM_END
) || stream
.total_out
!= size
) {
2025 #define MAX_DELTA_CACHE (256)
2027 static size_t delta_base_cached
;
2029 static struct delta_base_cache_lru_list
{
2030 struct delta_base_cache_lru_list
*prev
;
2031 struct delta_base_cache_lru_list
*next
;
2032 } delta_base_cache_lru
= { &delta_base_cache_lru
, &delta_base_cache_lru
};
2034 static struct delta_base_cache_entry
{
2035 struct delta_base_cache_lru_list lru
;
2037 struct packed_git
*p
;
2040 enum object_type type
;
2041 } delta_base_cache
[MAX_DELTA_CACHE
];
2043 static unsigned long pack_entry_hash(struct packed_git
*p
, off_t base_offset
)
2047 hash
= (unsigned long)p
+ (unsigned long)base_offset
;
2048 hash
+= (hash
>> 8) + (hash
>> 16);
2049 return hash
% MAX_DELTA_CACHE
;
2052 static struct delta_base_cache_entry
*
2053 get_delta_base_cache_entry(struct packed_git
*p
, off_t base_offset
)
2055 unsigned long hash
= pack_entry_hash(p
, base_offset
);
2056 return delta_base_cache
+ hash
;
2059 static int eq_delta_base_cache_entry(struct delta_base_cache_entry
*ent
,
2060 struct packed_git
*p
, off_t base_offset
)
2062 return (ent
->data
&& ent
->p
== p
&& ent
->base_offset
== base_offset
);
2065 static int in_delta_base_cache(struct packed_git
*p
, off_t base_offset
)
2067 struct delta_base_cache_entry
*ent
;
2068 ent
= get_delta_base_cache_entry(p
, base_offset
);
2069 return eq_delta_base_cache_entry(ent
, p
, base_offset
);
2072 static void clear_delta_base_cache_entry(struct delta_base_cache_entry
*ent
)
2075 ent
->lru
.next
->prev
= ent
->lru
.prev
;
2076 ent
->lru
.prev
->next
= ent
->lru
.next
;
2077 delta_base_cached
-= ent
->size
;
2080 static void *cache_or_unpack_entry(struct packed_git
*p
, off_t base_offset
,
2081 unsigned long *base_size
, enum object_type
*type
, int keep_cache
)
2083 struct delta_base_cache_entry
*ent
;
2086 ent
= get_delta_base_cache_entry(p
, base_offset
);
2088 if (!eq_delta_base_cache_entry(ent
, p
, base_offset
))
2089 return unpack_entry(p
, base_offset
, type
, base_size
);
2094 clear_delta_base_cache_entry(ent
);
2096 ret
= xmemdupz(ent
->data
, ent
->size
);
2098 *base_size
= ent
->size
;
2102 static inline void release_delta_base_cache(struct delta_base_cache_entry
*ent
)
2107 ent
->lru
.next
->prev
= ent
->lru
.prev
;
2108 ent
->lru
.prev
->next
= ent
->lru
.next
;
2109 delta_base_cached
-= ent
->size
;
2113 void clear_delta_base_cache(void)
2116 for (p
= 0; p
< MAX_DELTA_CACHE
; p
++)
2117 release_delta_base_cache(&delta_base_cache
[p
]);
2120 static void add_delta_base_cache(struct packed_git
*p
, off_t base_offset
,
2121 void *base
, unsigned long base_size
, enum object_type type
)
2123 unsigned long hash
= pack_entry_hash(p
, base_offset
);
2124 struct delta_base_cache_entry
*ent
= delta_base_cache
+ hash
;
2125 struct delta_base_cache_lru_list
*lru
;
2127 release_delta_base_cache(ent
);
2128 delta_base_cached
+= base_size
;
2130 for (lru
= delta_base_cache_lru
.next
;
2131 delta_base_cached
> delta_base_cache_limit
2132 && lru
!= &delta_base_cache_lru
;
2134 struct delta_base_cache_entry
*f
= (void *)lru
;
2135 if (f
->type
== OBJ_BLOB
)
2136 release_delta_base_cache(f
);
2138 for (lru
= delta_base_cache_lru
.next
;
2139 delta_base_cached
> delta_base_cache_limit
2140 && lru
!= &delta_base_cache_lru
;
2142 struct delta_base_cache_entry
*f
= (void *)lru
;
2143 release_delta_base_cache(f
);
2147 ent
->base_offset
= base_offset
;
2150 ent
->size
= base_size
;
2151 ent
->lru
.next
= &delta_base_cache_lru
;
2152 ent
->lru
.prev
= delta_base_cache_lru
.prev
;
2153 delta_base_cache_lru
.prev
->next
= &ent
->lru
;
2154 delta_base_cache_lru
.prev
= &ent
->lru
;
2157 static void *read_object(const unsigned char *sha1
, enum object_type
*type
,
2158 unsigned long *size
);
2160 static void write_pack_access_log(struct packed_git
*p
, off_t obj_offset
)
2162 static struct trace_key pack_access
= TRACE_KEY_INIT(PACK_ACCESS
);
2163 trace_printf_key(&pack_access
, "%s %"PRIuMAX
"\n",
2164 p
->pack_name
, (uintmax_t)obj_offset
);
2167 int do_check_packed_object_crc
;
2169 #define UNPACK_ENTRY_STACK_PREALLOC 64
2170 struct unpack_entry_stack_ent
{
2176 void *unpack_entry(struct packed_git
*p
, off_t obj_offset
,
2177 enum object_type
*final_type
, unsigned long *final_size
)
2179 struct pack_window
*w_curs
= NULL
;
2180 off_t curpos
= obj_offset
;
2183 enum object_type type
;
2184 struct unpack_entry_stack_ent small_delta_stack
[UNPACK_ENTRY_STACK_PREALLOC
];
2185 struct unpack_entry_stack_ent
*delta_stack
= small_delta_stack
;
2186 int delta_stack_nr
= 0, delta_stack_alloc
= UNPACK_ENTRY_STACK_PREALLOC
;
2187 int base_from_cache
= 0;
2189 write_pack_access_log(p
, obj_offset
);
2191 /* PHASE 1: drill down to the innermost base object */
2195 struct delta_base_cache_entry
*ent
;
2197 ent
= get_delta_base_cache_entry(p
, curpos
);
2198 if (eq_delta_base_cache_entry(ent
, p
, curpos
)) {
2202 clear_delta_base_cache_entry(ent
);
2203 base_from_cache
= 1;
2207 if (do_check_packed_object_crc
&& p
->index_version
> 1) {
2208 struct revindex_entry
*revidx
= find_pack_revindex(p
, obj_offset
);
2209 unsigned long len
= revidx
[1].offset
- obj_offset
;
2210 if (check_pack_crc(p
, &w_curs
, obj_offset
, len
, revidx
->nr
)) {
2211 const unsigned char *sha1
=
2212 nth_packed_object_sha1(p
, revidx
->nr
);
2213 error("bad packed object CRC for %s",
2215 mark_bad_packed_object(p
, sha1
);
2216 unuse_pack(&w_curs
);
2221 type
= unpack_object_header(p
, &w_curs
, &curpos
, &size
);
2222 if (type
!= OBJ_OFS_DELTA
&& type
!= OBJ_REF_DELTA
)
2225 base_offset
= get_delta_base(p
, &w_curs
, &curpos
, type
, obj_offset
);
2227 error("failed to validate delta base reference "
2228 "at offset %"PRIuMAX
" from %s",
2229 (uintmax_t)curpos
, p
->pack_name
);
2230 /* bail to phase 2, in hopes of recovery */
2235 /* push object, proceed to base */
2236 if (delta_stack_nr
>= delta_stack_alloc
2237 && delta_stack
== small_delta_stack
) {
2238 delta_stack_alloc
= alloc_nr(delta_stack_nr
);
2239 delta_stack
= xmalloc(sizeof(*delta_stack
)*delta_stack_alloc
);
2240 memcpy(delta_stack
, small_delta_stack
,
2241 sizeof(*delta_stack
)*delta_stack_nr
);
2243 ALLOC_GROW(delta_stack
, delta_stack_nr
+1, delta_stack_alloc
);
2245 i
= delta_stack_nr
++;
2246 delta_stack
[i
].obj_offset
= obj_offset
;
2247 delta_stack
[i
].curpos
= curpos
;
2248 delta_stack
[i
].size
= size
;
2250 curpos
= obj_offset
= base_offset
;
2253 /* PHASE 2: handle the base */
2258 die("BUG in unpack_entry: left loop at a valid delta");
2264 if (!base_from_cache
)
2265 data
= unpack_compressed_entry(p
, &w_curs
, curpos
, size
);
2269 error("unknown object type %i at offset %"PRIuMAX
" in %s",
2270 type
, (uintmax_t)obj_offset
, p
->pack_name
);
2273 /* PHASE 3: apply deltas in order */
2276 * 'data' holds the base data, or NULL if there was corruption
2278 while (delta_stack_nr
) {
2281 unsigned long delta_size
, base_size
= size
;
2287 add_delta_base_cache(p
, obj_offset
, base
, base_size
, type
);
2291 * We're probably in deep shit, but let's try to fetch
2292 * the required base anyway from another pack or loose.
2293 * This is costly but should happen only in the presence
2294 * of a corrupted pack, and is better than failing outright.
2296 struct revindex_entry
*revidx
;
2297 const unsigned char *base_sha1
;
2298 revidx
= find_pack_revindex(p
, obj_offset
);
2300 base_sha1
= nth_packed_object_sha1(p
, revidx
->nr
);
2301 error("failed to read delta base object %s"
2302 " at offset %"PRIuMAX
" from %s",
2303 sha1_to_hex(base_sha1
), (uintmax_t)obj_offset
,
2305 mark_bad_packed_object(p
, base_sha1
);
2306 base
= read_object(base_sha1
, &type
, &base_size
);
2310 i
= --delta_stack_nr
;
2311 obj_offset
= delta_stack
[i
].obj_offset
;
2312 curpos
= delta_stack
[i
].curpos
;
2313 delta_size
= delta_stack
[i
].size
;
2318 delta_data
= unpack_compressed_entry(p
, &w_curs
, curpos
, delta_size
);
2321 error("failed to unpack compressed delta "
2322 "at offset %"PRIuMAX
" from %s",
2323 (uintmax_t)curpos
, p
->pack_name
);
2328 data
= patch_delta(base
, base_size
,
2329 delta_data
, delta_size
,
2333 * We could not apply the delta; warn the user, but keep going.
2334 * Our failure will be noticed either in the next iteration of
2335 * the loop, or if this is the final delta, in the caller when
2336 * we return NULL. Those code paths will take care of making
2337 * a more explicit warning and retrying with another copy of
2341 error("failed to apply delta");
2349 unuse_pack(&w_curs
);
2351 if (delta_stack
!= small_delta_stack
)
2357 const unsigned char *nth_packed_object_sha1(struct packed_git
*p
,
2360 const unsigned char *index
= p
->index_data
;
2362 if (open_pack_index(p
))
2364 index
= p
->index_data
;
2366 if (n
>= p
->num_objects
)
2369 if (p
->index_version
== 1) {
2370 return index
+ 24 * n
+ 4;
2373 return index
+ 20 * n
;
2377 off_t
nth_packed_object_offset(const struct packed_git
*p
, uint32_t n
)
2379 const unsigned char *index
= p
->index_data
;
2381 if (p
->index_version
== 1) {
2382 return ntohl(*((uint32_t *)(index
+ 24 * n
)));
2385 index
+= 8 + p
->num_objects
* (20 + 4);
2386 off
= ntohl(*((uint32_t *)(index
+ 4 * n
)));
2387 if (!(off
& 0x80000000))
2389 index
+= p
->num_objects
* 4 + (off
& 0x7fffffff) * 8;
2390 return (((uint64_t)ntohl(*((uint32_t *)(index
+ 0)))) << 32) |
2391 ntohl(*((uint32_t *)(index
+ 4)));
2395 off_t
find_pack_entry_one(const unsigned char *sha1
,
2396 struct packed_git
*p
)
2398 const uint32_t *level1_ofs
= p
->index_data
;
2399 const unsigned char *index
= p
->index_data
;
2400 unsigned hi
, lo
, stride
;
2401 static int use_lookup
= -1;
2402 static int debug_lookup
= -1;
2404 if (debug_lookup
< 0)
2405 debug_lookup
= !!getenv("GIT_DEBUG_LOOKUP");
2408 if (open_pack_index(p
))
2410 level1_ofs
= p
->index_data
;
2411 index
= p
->index_data
;
2413 if (p
->index_version
> 1) {
2418 hi
= ntohl(level1_ofs
[*sha1
]);
2419 lo
= ((*sha1
== 0x0) ? 0 : ntohl(level1_ofs
[*sha1
- 1]));
2420 if (p
->index_version
> 1) {
2428 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32
"\n",
2429 sha1
[0], sha1
[1], sha1
[2], lo
, hi
, p
->num_objects
);
2432 use_lookup
= !!getenv("GIT_USE_LOOKUP");
2434 int pos
= sha1_entry_pos(index
, stride
, 0,
2435 lo
, hi
, p
->num_objects
, sha1
);
2438 return nth_packed_object_offset(p
, pos
);
2442 unsigned mi
= (lo
+ hi
) / 2;
2443 int cmp
= hashcmp(index
+ mi
* stride
, sha1
);
2446 printf("lo %u hi %u rg %u mi %u\n",
2447 lo
, hi
, hi
- lo
, mi
);
2449 return nth_packed_object_offset(p
, mi
);
2458 int is_pack_valid(struct packed_git
*p
)
2460 /* An already open pack is known to be valid. */
2461 if (p
->pack_fd
!= -1)
2464 /* If the pack has one window completely covering the
2465 * file size, the pack is known to be valid even if
2466 * the descriptor is not currently open.
2469 struct pack_window
*w
= p
->windows
;
2471 if (!w
->offset
&& w
->len
== p
->pack_size
)
2475 /* Force the pack to open to prove its valid. */
2476 return !open_packed_git(p
);
2479 static int fill_pack_entry(const unsigned char *sha1
,
2480 struct pack_entry
*e
,
2481 struct packed_git
*p
)
2485 if (p
->num_bad_objects
) {
2487 for (i
= 0; i
< p
->num_bad_objects
; i
++)
2488 if (!hashcmp(sha1
, p
->bad_object_sha1
+ 20 * i
))
2492 offset
= find_pack_entry_one(sha1
, p
);
2497 * We are about to tell the caller where they can locate the
2498 * requested object. We better make sure the packfile is
2499 * still here and can be accessed before supplying that
2500 * answer, as it may have been deleted since the index was
2503 if (!is_pack_valid(p
))
2507 hashcpy(e
->sha1
, sha1
);
2512 * Iff a pack file contains the object named by sha1, return true and
2513 * store its location to e.
2515 static int find_pack_entry(const unsigned char *sha1
, struct pack_entry
*e
)
2517 struct packed_git
*p
;
2519 prepare_packed_git();
2523 if (last_found_pack
&& fill_pack_entry(sha1
, e
, last_found_pack
))
2526 for (p
= packed_git
; p
; p
= p
->next
) {
2527 if (p
== last_found_pack
)
2528 continue; /* we already checked this one */
2530 if (fill_pack_entry(sha1
, e
, p
)) {
2531 last_found_pack
= p
;
2538 struct packed_git
*find_sha1_pack(const unsigned char *sha1
,
2539 struct packed_git
*packs
)
2541 struct packed_git
*p
;
2543 for (p
= packs
; p
; p
= p
->next
) {
2544 if (find_pack_entry_one(sha1
, p
))
2551 static int sha1_loose_object_info(const unsigned char *sha1
,
2552 struct object_info
*oi
)
2555 unsigned long mapsize
, size
;
2560 if (oi
->delta_base_sha1
)
2561 hashclr(oi
->delta_base_sha1
);
2564 * If we don't care about type or size, then we don't
2565 * need to look inside the object at all. Note that we
2566 * do not optimize out the stat call, even if the
2567 * caller doesn't care about the disk-size, since our
2568 * return value implicitly indicates whether the
2569 * object even exists.
2571 if (!oi
->typep
&& !oi
->sizep
) {
2573 if (stat_sha1_file(sha1
, &st
) < 0)
2576 *oi
->disk_sizep
= st
.st_size
;
2580 map
= map_sha1_file(sha1
, &mapsize
);
2584 *oi
->disk_sizep
= mapsize
;
2585 if (unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
)) < 0)
2586 status
= error("unable to unpack %s header",
2588 else if ((status
= parse_sha1_header(hdr
, &size
)) < 0)
2589 status
= error("unable to parse %s header", sha1_to_hex(sha1
));
2592 git_inflate_end(&stream
);
2593 munmap(map
, mapsize
);
2595 *oi
->typep
= status
;
2599 int sha1_object_info_extended(const unsigned char *sha1
, struct object_info
*oi
, unsigned flags
)
2601 struct cached_object
*co
;
2602 struct pack_entry e
;
2604 const unsigned char *real
= lookup_replace_object_extended(sha1
, flags
);
2606 co
= find_cached_object(real
);
2609 *(oi
->typep
) = co
->type
;
2611 *(oi
->sizep
) = co
->size
;
2613 *(oi
->disk_sizep
) = 0;
2614 if (oi
->delta_base_sha1
)
2615 hashclr(oi
->delta_base_sha1
);
2616 oi
->whence
= OI_CACHED
;
2620 if (!find_pack_entry(real
, &e
)) {
2621 /* Most likely it's a loose object. */
2622 if (!sha1_loose_object_info(real
, oi
)) {
2623 oi
->whence
= OI_LOOSE
;
2627 /* Not a loose object; someone else may have just packed it. */
2628 reprepare_packed_git();
2629 if (!find_pack_entry(real
, &e
))
2633 rtype
= packed_object_info(e
.p
, e
.offset
, oi
);
2635 mark_bad_packed_object(e
.p
, real
);
2636 return sha1_object_info_extended(real
, oi
, 0);
2637 } else if (in_delta_base_cache(e
.p
, e
.offset
)) {
2638 oi
->whence
= OI_DBCACHED
;
2640 oi
->whence
= OI_PACKED
;
2641 oi
->u
.packed
.offset
= e
.offset
;
2642 oi
->u
.packed
.pack
= e
.p
;
2643 oi
->u
.packed
.is_delta
= (rtype
== OBJ_REF_DELTA
||
2644 rtype
== OBJ_OFS_DELTA
);
2650 /* returns enum object_type or negative */
2651 int sha1_object_info(const unsigned char *sha1
, unsigned long *sizep
)
2653 enum object_type type
;
2654 struct object_info oi
= {NULL
};
2658 if (sha1_object_info_extended(sha1
, &oi
, LOOKUP_REPLACE_OBJECT
) < 0)
2663 static void *read_packed_sha1(const unsigned char *sha1
,
2664 enum object_type
*type
, unsigned long *size
)
2666 struct pack_entry e
;
2669 if (!find_pack_entry(sha1
, &e
))
2671 data
= cache_or_unpack_entry(e
.p
, e
.offset
, size
, type
, 1);
2674 * We're probably in deep shit, but let's try to fetch
2675 * the required object anyway from another pack or loose.
2676 * This should happen only in the presence of a corrupted
2677 * pack, and is better than failing outright.
2679 error("failed to read object %s at offset %"PRIuMAX
" from %s",
2680 sha1_to_hex(sha1
), (uintmax_t)e
.offset
, e
.p
->pack_name
);
2681 mark_bad_packed_object(e
.p
, sha1
);
2682 data
= read_object(sha1
, type
, size
);
2687 int pretend_sha1_file(void *buf
, unsigned long len
, enum object_type type
,
2688 unsigned char *sha1
)
2690 struct cached_object
*co
;
2692 hash_sha1_file(buf
, len
, typename(type
), sha1
);
2693 if (has_sha1_file(sha1
) || find_cached_object(sha1
))
2695 ALLOC_GROW(cached_objects
, cached_object_nr
+ 1, cached_object_alloc
);
2696 co
= &cached_objects
[cached_object_nr
++];
2699 co
->buf
= xmalloc(len
);
2700 memcpy(co
->buf
, buf
, len
);
2701 hashcpy(co
->sha1
, sha1
);
2705 static void *read_object(const unsigned char *sha1
, enum object_type
*type
,
2706 unsigned long *size
)
2708 unsigned long mapsize
;
2710 struct cached_object
*co
;
2712 co
= find_cached_object(sha1
);
2716 return xmemdupz(co
->buf
, co
->size
);
2719 buf
= read_packed_sha1(sha1
, type
, size
);
2722 map
= map_sha1_file(sha1
, &mapsize
);
2724 buf
= unpack_sha1_file(map
, mapsize
, type
, size
, sha1
);
2725 munmap(map
, mapsize
);
2728 reprepare_packed_git();
2729 return read_packed_sha1(sha1
, type
, size
);
2733 * This function dies on corrupt objects; the callers who want to
2734 * deal with them should arrange to call read_object() and give error
2735 * messages themselves.
2737 void *read_sha1_file_extended(const unsigned char *sha1
,
2738 enum object_type
*type
,
2739 unsigned long *size
,
2743 const struct packed_git
*p
;
2744 const unsigned char *repl
= lookup_replace_object_extended(sha1
, flag
);
2747 data
= read_object(repl
, type
, size
);
2751 if (errno
&& errno
!= ENOENT
)
2752 die_errno("failed to read object %s", sha1_to_hex(sha1
));
2754 /* die if we replaced an object with one that does not exist */
2756 die("replacement %s not found for %s",
2757 sha1_to_hex(repl
), sha1_to_hex(sha1
));
2759 if (has_loose_object(repl
)) {
2760 const char *path
= sha1_file_name(sha1
);
2762 die("loose object %s (stored in %s) is corrupt",
2763 sha1_to_hex(repl
), path
);
2766 if ((p
= has_packed_and_bad(repl
)) != NULL
)
2767 die("packed object %s (stored in %s) is corrupt",
2768 sha1_to_hex(repl
), p
->pack_name
);
2773 void *read_object_with_reference(const unsigned char *sha1
,
2774 const char *required_type_name
,
2775 unsigned long *size
,
2776 unsigned char *actual_sha1_return
)
2778 enum object_type type
, required_type
;
2780 unsigned long isize
;
2781 unsigned char actual_sha1
[20];
2783 required_type
= type_from_string(required_type_name
);
2784 hashcpy(actual_sha1
, sha1
);
2786 int ref_length
= -1;
2787 const char *ref_type
= NULL
;
2789 buffer
= read_sha1_file(actual_sha1
, &type
, &isize
);
2792 if (type
== required_type
) {
2794 if (actual_sha1_return
)
2795 hashcpy(actual_sha1_return
, actual_sha1
);
2798 /* Handle references */
2799 else if (type
== OBJ_COMMIT
)
2801 else if (type
== OBJ_TAG
)
2802 ref_type
= "object ";
2807 ref_length
= strlen(ref_type
);
2809 if (ref_length
+ 40 > isize
||
2810 memcmp(buffer
, ref_type
, ref_length
) ||
2811 get_sha1_hex((char *) buffer
+ ref_length
, actual_sha1
)) {
2816 /* Now we have the ID of the referred-to object in
2817 * actual_sha1. Check again. */
2821 static void write_sha1_file_prepare(const void *buf
, unsigned long len
,
2822 const char *type
, unsigned char *sha1
,
2823 char *hdr
, int *hdrlen
)
2827 /* Generate the header */
2828 *hdrlen
= sprintf(hdr
, "%s %lu", type
, len
)+1;
2832 git_SHA1_Update(&c
, hdr
, *hdrlen
);
2833 git_SHA1_Update(&c
, buf
, len
);
2834 git_SHA1_Final(sha1
, &c
);
2838 * Move the just written object into its final resting place.
2839 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2840 * "moving" is only a part of what it does, when no patch between
2841 * master to pu changes the call sites of this function.
2843 int move_temp_to_file(const char *tmpfile
, const char *filename
)
2847 if (object_creation_mode
== OBJECT_CREATION_USES_RENAMES
)
2849 else if (link(tmpfile
, filename
))
2853 * Coda hack - coda doesn't like cross-directory links,
2854 * so we fall back to a rename, which will mean that it
2855 * won't be able to check collisions, but that's not a
2858 * The same holds for FAT formatted media.
2860 * When this succeeds, we just return. We have nothing
2863 if (ret
&& ret
!= EEXIST
) {
2865 if (!rename(tmpfile
, filename
))
2869 unlink_or_warn(tmpfile
);
2871 if (ret
!= EEXIST
) {
2872 return error("unable to write sha1 filename %s: %s", filename
, strerror(ret
));
2874 /* FIXME!!! Collision check here ? */
2878 if (adjust_shared_perm(filename
))
2879 return error("unable to set permission to '%s'", filename
);
2883 static int write_buffer(int fd
, const void *buf
, size_t len
)
2885 if (write_in_full(fd
, buf
, len
) < 0)
2886 return error("file write error (%s)", strerror(errno
));
2890 int hash_sha1_file(const void *buf
, unsigned long len
, const char *type
,
2891 unsigned char *sha1
)
2895 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
2899 /* Finalize a file on disk, and close it. */
2900 static void close_sha1_file(int fd
)
2902 if (fsync_object_files
)
2903 fsync_or_die(fd
, "sha1 file");
2905 die_errno("error when closing sha1 file");
2908 /* Size of directory component, including the ending '/' */
2909 static inline int directory_size(const char *filename
)
2911 const char *s
= strrchr(filename
, '/');
2914 return s
- filename
+ 1;
2918 * This creates a temporary file in the same directory as the final
2921 * We want to avoid cross-directory filename renames, because those
2922 * can have problems on various filesystems (FAT, NFS, Coda).
2924 static int create_tmpfile(char *buffer
, size_t bufsiz
, const char *filename
)
2926 int fd
, dirlen
= directory_size(filename
);
2928 if (dirlen
+ 20 > bufsiz
) {
2929 errno
= ENAMETOOLONG
;
2932 memcpy(buffer
, filename
, dirlen
);
2933 strcpy(buffer
+ dirlen
, "tmp_obj_XXXXXX");
2934 fd
= git_mkstemp_mode(buffer
, 0444);
2935 if (fd
< 0 && dirlen
&& errno
== ENOENT
) {
2936 /* Make sure the directory exists */
2937 memcpy(buffer
, filename
, dirlen
);
2938 buffer
[dirlen
-1] = 0;
2939 if (mkdir(buffer
, 0777) && errno
!= EEXIST
)
2941 if (adjust_shared_perm(buffer
))
2945 strcpy(buffer
+ dirlen
- 1, "/tmp_obj_XXXXXX");
2946 fd
= git_mkstemp_mode(buffer
, 0444);
2951 static int write_loose_object(const unsigned char *sha1
, char *hdr
, int hdrlen
,
2952 const void *buf
, unsigned long len
, time_t mtime
)
2955 unsigned char compressed
[4096];
2958 unsigned char parano_sha1
[20];
2959 static char tmp_file
[PATH_MAX
];
2960 const char *filename
= sha1_file_name(sha1
);
2962 fd
= create_tmpfile(tmp_file
, sizeof(tmp_file
), filename
);
2964 if (errno
== EACCES
)
2965 return error("insufficient permission for adding an object to repository database %s", get_object_directory());
2967 return error("unable to create temporary file: %s", strerror(errno
));
2971 git_deflate_init(&stream
, zlib_compression_level
);
2972 stream
.next_out
= compressed
;
2973 stream
.avail_out
= sizeof(compressed
);
2976 /* First header.. */
2977 stream
.next_in
= (unsigned char *)hdr
;
2978 stream
.avail_in
= hdrlen
;
2979 while (git_deflate(&stream
, 0) == Z_OK
)
2981 git_SHA1_Update(&c
, hdr
, hdrlen
);
2983 /* Then the data itself.. */
2984 stream
.next_in
= (void *)buf
;
2985 stream
.avail_in
= len
;
2987 unsigned char *in0
= stream
.next_in
;
2988 ret
= git_deflate(&stream
, Z_FINISH
);
2989 git_SHA1_Update(&c
, in0
, stream
.next_in
- in0
);
2990 if (write_buffer(fd
, compressed
, stream
.next_out
- compressed
) < 0)
2991 die("unable to write sha1 file");
2992 stream
.next_out
= compressed
;
2993 stream
.avail_out
= sizeof(compressed
);
2994 } while (ret
== Z_OK
);
2996 if (ret
!= Z_STREAM_END
)
2997 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1
), ret
);
2998 ret
= git_deflate_end_gently(&stream
);
3000 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1
), ret
);
3001 git_SHA1_Final(parano_sha1
, &c
);
3002 if (hashcmp(sha1
, parano_sha1
) != 0)
3003 die("confused by unstable object source data for %s", sha1_to_hex(sha1
));
3005 close_sha1_file(fd
);
3010 utb
.modtime
= mtime
;
3011 if (utime(tmp_file
, &utb
) < 0)
3012 warning("failed utime() on %s: %s",
3013 tmp_file
, strerror(errno
));
3016 return move_temp_to_file(tmp_file
, filename
);
3019 static int freshen_loose_object(const unsigned char *sha1
)
3021 return check_and_freshen(sha1
, 1);
3024 static int freshen_packed_object(const unsigned char *sha1
)
3026 struct pack_entry e
;
3027 if (!find_pack_entry(sha1
, &e
))
3031 if (!freshen_file(e
.p
->pack_name
))
3037 int write_sha1_file(const void *buf
, unsigned long len
, const char *type
, unsigned char *sha1
)
3042 /* Normally if we have it in the pack then we do not bother writing
3043 * it out into .git/objects/??/?{38} file.
3045 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
3046 if (freshen_packed_object(sha1
) || freshen_loose_object(sha1
))
3048 return write_loose_object(sha1
, hdr
, hdrlen
, buf
, len
, 0);
3051 int hash_sha1_file_literally(const void *buf
, unsigned long len
, const char *type
,
3052 unsigned char *sha1
, unsigned flags
)
3055 int hdrlen
, status
= 0;
3057 /* type string, SP, %lu of the length plus NUL must fit this */
3058 header
= xmalloc(strlen(type
) + 32);
3059 write_sha1_file_prepare(buf
, len
, type
, sha1
, header
, &hdrlen
);
3061 if (!(flags
& HASH_WRITE_OBJECT
))
3063 if (freshen_packed_object(sha1
) || freshen_loose_object(sha1
))
3065 status
= write_loose_object(sha1
, header
, hdrlen
, buf
, len
, 0);
3072 int force_object_loose(const unsigned char *sha1
, time_t mtime
)
3076 enum object_type type
;
3081 if (has_loose_object(sha1
))
3083 buf
= read_packed_sha1(sha1
, &type
, &len
);
3085 return error("cannot read sha1_file for %s", sha1_to_hex(sha1
));
3086 hdrlen
= sprintf(hdr
, "%s %lu", typename(type
), len
) + 1;
3087 ret
= write_loose_object(sha1
, hdr
, hdrlen
, buf
, len
, mtime
);
3093 int has_pack_index(const unsigned char *sha1
)
3096 if (stat(sha1_pack_index_name(sha1
), &st
))
3101 int has_sha1_pack(const unsigned char *sha1
)
3103 struct pack_entry e
;
3104 return find_pack_entry(sha1
, &e
);
3107 int has_sha1_file_with_flags(const unsigned char *sha1
, int flags
)
3109 struct pack_entry e
;
3111 if (find_pack_entry(sha1
, &e
))
3113 if (has_loose_object(sha1
))
3115 if (flags
& HAS_SHA1_QUICK
)
3117 reprepare_packed_git();
3118 return find_pack_entry(sha1
, &e
);
3121 static void check_tree(const void *buf
, size_t size
)
3123 struct tree_desc desc
;
3124 struct name_entry entry
;
3126 init_tree_desc(&desc
, buf
, size
);
3127 while (tree_entry(&desc
, &entry
))
3129 * tree_entry() will die() on malformed entries */
3133 static void check_commit(const void *buf
, size_t size
)
3136 memset(&c
, 0, sizeof(c
));
3137 if (parse_commit_buffer(&c
, buf
, size
))
3138 die("corrupt commit");
3141 static void check_tag(const void *buf
, size_t size
)
3144 memset(&t
, 0, sizeof(t
));
3145 if (parse_tag_buffer(&t
, buf
, size
))
3149 static int index_mem(unsigned char *sha1
, void *buf
, size_t size
,
3150 enum object_type type
,
3151 const char *path
, unsigned flags
)
3153 int ret
, re_allocated
= 0;
3154 int write_object
= flags
& HASH_WRITE_OBJECT
;
3160 * Convert blobs to git internal format
3162 if ((type
== OBJ_BLOB
) && path
) {
3163 struct strbuf nbuf
= STRBUF_INIT
;
3164 if (convert_to_git(path
, buf
, size
, &nbuf
,
3165 write_object
? safe_crlf
: SAFE_CRLF_FALSE
)) {
3166 buf
= strbuf_detach(&nbuf
, &size
);
3170 if (flags
& HASH_FORMAT_CHECK
) {
3171 if (type
== OBJ_TREE
)
3172 check_tree(buf
, size
);
3173 if (type
== OBJ_COMMIT
)
3174 check_commit(buf
, size
);
3175 if (type
== OBJ_TAG
)
3176 check_tag(buf
, size
);
3180 ret
= write_sha1_file(buf
, size
, typename(type
), sha1
);
3182 ret
= hash_sha1_file(buf
, size
, typename(type
), sha1
);
3188 static int index_stream_convert_blob(unsigned char *sha1
, int fd
,
3189 const char *path
, unsigned flags
)
3192 const int write_object
= flags
& HASH_WRITE_OBJECT
;
3193 struct strbuf sbuf
= STRBUF_INIT
;
3196 assert(would_convert_to_git_filter_fd(path
));
3198 convert_to_git_filter_fd(path
, fd
, &sbuf
,
3199 write_object
? safe_crlf
: SAFE_CRLF_FALSE
);
3202 ret
= write_sha1_file(sbuf
.buf
, sbuf
.len
, typename(OBJ_BLOB
),
3205 ret
= hash_sha1_file(sbuf
.buf
, sbuf
.len
, typename(OBJ_BLOB
),
3207 strbuf_release(&sbuf
);
3211 static int index_pipe(unsigned char *sha1
, int fd
, enum object_type type
,
3212 const char *path
, unsigned flags
)
3214 struct strbuf sbuf
= STRBUF_INIT
;
3217 if (strbuf_read(&sbuf
, fd
, 4096) >= 0)
3218 ret
= index_mem(sha1
, sbuf
.buf
, sbuf
.len
, type
, path
, flags
);
3221 strbuf_release(&sbuf
);
3225 #define SMALL_FILE_SIZE (32*1024)
3227 static int index_core(unsigned char *sha1
, int fd
, size_t size
,
3228 enum object_type type
, const char *path
,
3234 ret
= index_mem(sha1
, "", size
, type
, path
, flags
);
3235 } else if (size
<= SMALL_FILE_SIZE
) {
3236 char *buf
= xmalloc(size
);
3237 if (size
== read_in_full(fd
, buf
, size
))
3238 ret
= index_mem(sha1
, buf
, size
, type
, path
, flags
);
3240 ret
= error("short read %s", strerror(errno
));
3243 void *buf
= xmmap(NULL
, size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
3244 ret
= index_mem(sha1
, buf
, size
, type
, path
, flags
);
3251 * This creates one packfile per large blob unless bulk-checkin
3252 * machinery is "plugged".
3254 * This also bypasses the usual "convert-to-git" dance, and that is on
3255 * purpose. We could write a streaming version of the converting
3256 * functions and insert that before feeding the data to fast-import
3257 * (or equivalent in-core API described above). However, that is
3258 * somewhat complicated, as we do not know the size of the filter
3259 * result, which we need to know beforehand when writing a git object.
3260 * Since the primary motivation for trying to stream from the working
3261 * tree file and to avoid mmaping it in core is to deal with large
3262 * binary blobs, they generally do not want to get any conversion, and
3263 * callers should avoid this code path when filters are requested.
3265 static int index_stream(unsigned char *sha1
, int fd
, size_t size
,
3266 enum object_type type
, const char *path
,
3269 return index_bulk_checkin(sha1
, fd
, size
, type
, path
, flags
);
3272 int index_fd(unsigned char *sha1
, int fd
, struct stat
*st
,
3273 enum object_type type
, const char *path
, unsigned flags
)
3278 * Call xsize_t() only when needed to avoid potentially unnecessary
3279 * die() for large files.
3281 if (type
== OBJ_BLOB
&& path
&& would_convert_to_git_filter_fd(path
))
3282 ret
= index_stream_convert_blob(sha1
, fd
, path
, flags
);
3283 else if (!S_ISREG(st
->st_mode
))
3284 ret
= index_pipe(sha1
, fd
, type
, path
, flags
);
3285 else if (st
->st_size
<= big_file_threshold
|| type
!= OBJ_BLOB
||
3286 (path
&& would_convert_to_git(path
)))
3287 ret
= index_core(sha1
, fd
, xsize_t(st
->st_size
), type
, path
,
3290 ret
= index_stream(sha1
, fd
, xsize_t(st
->st_size
), type
, path
,
3296 int index_path(unsigned char *sha1
, const char *path
, struct stat
*st
, unsigned flags
)
3299 struct strbuf sb
= STRBUF_INIT
;
3301 switch (st
->st_mode
& S_IFMT
) {
3303 fd
= open(path
, O_RDONLY
);
3305 return error("open(\"%s\"): %s", path
,
3307 if (index_fd(sha1
, fd
, st
, OBJ_BLOB
, path
, flags
) < 0)
3308 return error("%s: failed to insert into database",
3312 if (strbuf_readlink(&sb
, path
, st
->st_size
)) {
3313 char *errstr
= strerror(errno
);
3314 return error("readlink(\"%s\"): %s", path
,
3317 if (!(flags
& HASH_WRITE_OBJECT
))
3318 hash_sha1_file(sb
.buf
, sb
.len
, blob_type
, sha1
);
3319 else if (write_sha1_file(sb
.buf
, sb
.len
, blob_type
, sha1
))
3320 return error("%s: failed to insert into database",
3322 strbuf_release(&sb
);
3325 return resolve_gitlink_ref(path
, "HEAD", sha1
);
3327 return error("%s: unsupported file type", path
);
3332 int read_pack_header(int fd
, struct pack_header
*header
)
3334 if (read_in_full(fd
, header
, sizeof(*header
)) < sizeof(*header
))
3335 /* "eof before pack header was fully read" */
3336 return PH_ERROR_EOF
;
3338 if (header
->hdr_signature
!= htonl(PACK_SIGNATURE
))
3339 /* "protocol error (pack signature mismatch detected)" */
3340 return PH_ERROR_PACK_SIGNATURE
;
3341 if (!pack_version_ok(header
->hdr_version
))
3342 /* "protocol error (pack version unsupported)" */
3343 return PH_ERROR_PROTOCOL
;
3347 void assert_sha1_type(const unsigned char *sha1
, enum object_type expect
)
3349 enum object_type type
= sha1_object_info(sha1
, NULL
);
3351 die("%s is not a valid object", sha1_to_hex(sha1
));
3353 die("%s is not a valid '%s' object", sha1_to_hex(sha1
),
3357 static int for_each_file_in_obj_subdir(int subdir_nr
,
3358 struct strbuf
*path
,
3359 each_loose_object_fn obj_cb
,
3360 each_loose_cruft_fn cruft_cb
,
3361 each_loose_subdir_fn subdir_cb
,
3364 size_t baselen
= path
->len
;
3365 DIR *dir
= opendir(path
->buf
);
3370 if (errno
== ENOENT
)
3372 return error("unable to open %s: %s", path
->buf
, strerror(errno
));
3375 while ((de
= readdir(dir
))) {
3376 if (is_dot_or_dotdot(de
->d_name
))
3379 strbuf_setlen(path
, baselen
);
3380 strbuf_addf(path
, "/%s", de
->d_name
);
3382 if (strlen(de
->d_name
) == 38) {
3384 unsigned char sha1
[20];
3386 snprintf(hex
, sizeof(hex
), "%02x%s",
3387 subdir_nr
, de
->d_name
);
3388 if (!get_sha1_hex(hex
, sha1
)) {
3390 r
= obj_cb(sha1
, path
->buf
, data
);
3399 r
= cruft_cb(de
->d_name
, path
->buf
, data
);
3404 strbuf_setlen(path
, baselen
);
3406 if (!r
&& subdir_cb
)
3407 r
= subdir_cb(subdir_nr
, path
->buf
, data
);
3413 int for_each_loose_file_in_objdir_buf(struct strbuf
*path
,
3414 each_loose_object_fn obj_cb
,
3415 each_loose_cruft_fn cruft_cb
,
3416 each_loose_subdir_fn subdir_cb
,
3419 size_t baselen
= path
->len
;
3423 for (i
= 0; i
< 256; i
++) {
3424 strbuf_addf(path
, "/%02x", i
);
3425 r
= for_each_file_in_obj_subdir(i
, path
, obj_cb
, cruft_cb
,
3427 strbuf_setlen(path
, baselen
);
3435 int for_each_loose_file_in_objdir(const char *path
,
3436 each_loose_object_fn obj_cb
,
3437 each_loose_cruft_fn cruft_cb
,
3438 each_loose_subdir_fn subdir_cb
,
3441 struct strbuf buf
= STRBUF_INIT
;
3444 strbuf_addstr(&buf
, path
);
3445 r
= for_each_loose_file_in_objdir_buf(&buf
, obj_cb
, cruft_cb
,
3447 strbuf_release(&buf
);
3452 struct loose_alt_odb_data
{
3453 each_loose_object_fn
*cb
;
3457 static int loose_from_alt_odb(struct alternate_object_database
*alt
,
3460 struct loose_alt_odb_data
*data
= vdata
;
3461 struct strbuf buf
= STRBUF_INIT
;
3464 /* copy base not including trailing '/' */
3465 strbuf_add(&buf
, alt
->base
, alt
->name
- alt
->base
- 1);
3466 r
= for_each_loose_file_in_objdir_buf(&buf
,
3467 data
->cb
, NULL
, NULL
,
3469 strbuf_release(&buf
);
3473 int for_each_loose_object(each_loose_object_fn cb
, void *data
, unsigned flags
)
3475 struct loose_alt_odb_data alt
;
3478 r
= for_each_loose_file_in_objdir(get_object_directory(),
3479 cb
, NULL
, NULL
, data
);
3483 if (flags
& FOR_EACH_OBJECT_LOCAL_ONLY
)
3488 return foreach_alt_odb(loose_from_alt_odb
, &alt
);
3491 static int for_each_object_in_pack(struct packed_git
*p
, each_packed_object_fn cb
, void *data
)
3496 for (i
= 0; i
< p
->num_objects
; i
++) {
3497 const unsigned char *sha1
= nth_packed_object_sha1(p
, i
);
3500 return error("unable to get sha1 of object %u in %s",
3503 r
= cb(sha1
, p
, i
, data
);
3510 int for_each_packed_object(each_packed_object_fn cb
, void *data
, unsigned flags
)
3512 struct packed_git
*p
;
3515 prepare_packed_git();
3516 for (p
= packed_git
; p
; p
= p
->next
) {
3517 if ((flags
& FOR_EACH_OBJECT_LOCAL_ONLY
) && !p
->pack_local
)
3519 r
= for_each_object_in_pack(p
, cb
, data
);