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"
15 #include "run-command.h"
18 #include "tree-walk.h"
20 #include "pack-revindex.h"
21 #include "sha1-lookup.h"
22 #include "bulk-checkin.h"
23 #include "streaming.h"
27 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
28 #define O_NOATIME 01000000
34 #define SZ_FMT PRIuMAX
35 static inline uintmax_t sz_fmt(size_t s
) { return s
; }
37 const unsigned char null_sha1
[20];
40 * This is meant to hold a *small* number of objects that you would
41 * want read_sha1_file() to be able to return, but yet you do not want
42 * to write them into the object store (e.g. a browse-only
45 static struct cached_object
{
46 unsigned char sha1
[20];
47 enum object_type type
;
51 static int cached_object_nr
, cached_object_alloc
;
53 static struct cached_object empty_tree
= {
54 EMPTY_TREE_SHA1_BIN_LITERAL
,
61 * A pointer to the last packed_git in which an object was found.
62 * When an object is sought, we look in this packfile first, because
63 * objects that are looked up at similar times are often in the same
64 * packfile as one another.
66 static struct packed_git
*last_found_pack
;
68 static struct cached_object
*find_cached_object(const unsigned char *sha1
)
71 struct cached_object
*co
= cached_objects
;
73 for (i
= 0; i
< cached_object_nr
; i
++, co
++) {
74 if (!hashcmp(co
->sha1
, sha1
))
77 if (!hashcmp(sha1
, empty_tree
.sha1
))
82 int mkdir_in_gitdir(const char *path
)
84 if (mkdir(path
, 0777)) {
85 int saved_errno
= errno
;
87 struct strbuf sb
= STRBUF_INIT
;
92 * Are we looking at a path in a symlinked worktree
93 * whose original repository does not yet have it?
94 * e.g. .git/rr-cache pointing at its original
95 * repository in which the user hasn't performed any
96 * conflict resolution yet?
98 if (lstat(path
, &st
) || !S_ISLNK(st
.st_mode
) ||
99 strbuf_readlink(&sb
, path
, st
.st_size
) ||
100 !is_absolute_path(sb
.buf
) ||
101 mkdir(sb
.buf
, 0777)) {
108 return adjust_shared_perm(path
);
111 enum scld_error
safe_create_leading_directories(char *path
)
113 char *next_component
= path
+ offset_1st_component(path
);
114 enum scld_error ret
= SCLD_OK
;
116 while (ret
== SCLD_OK
&& next_component
) {
118 char *slash
= next_component
, slash_character
;
120 while (*slash
&& !is_dir_sep(*slash
))
126 next_component
= slash
+ 1;
127 while (is_dir_sep(*next_component
))
129 if (!*next_component
)
132 slash_character
= *slash
;
134 if (!stat(path
, &st
)) {
136 if (!S_ISDIR(st
.st_mode
))
138 } else if (mkdir(path
, 0777)) {
139 if (errno
== EEXIST
&&
140 !stat(path
, &st
) && S_ISDIR(st
.st_mode
))
141 ; /* somebody created it since we checked */
142 else if (errno
== ENOENT
)
144 * Either mkdir() failed because
145 * somebody just pruned the containing
146 * directory, or stat() failed because
147 * the file that was in our way was
148 * just removed. Either way, inform
149 * the caller that it might be worth
155 } else if (adjust_shared_perm(path
)) {
158 *slash
= slash_character
;
163 enum scld_error
safe_create_leading_directories_const(const char *path
)
165 /* path points to cache entries, so xstrdup before messing with it */
166 char *buf
= xstrdup(path
);
167 enum scld_error result
= safe_create_leading_directories(buf
);
172 static void fill_sha1_path(char *pathbuf
, const unsigned char *sha1
)
175 for (i
= 0; i
< 20; i
++) {
176 static char hex
[] = "0123456789abcdef";
177 unsigned int val
= sha1
[i
];
178 char *pos
= pathbuf
+ i
*2 + (i
> 0);
179 *pos
++ = hex
[val
>> 4];
180 *pos
= hex
[val
& 0xf];
184 const char *sha1_file_name(const unsigned char *sha1
)
186 static char buf
[PATH_MAX
];
190 objdir
= get_object_directory();
191 len
= strlen(objdir
);
193 /* '/' + sha1(2) + '/' + sha1(38) + '\0' */
194 if (len
+ 43 > PATH_MAX
)
195 die("insanely long object directory %s", objdir
);
196 memcpy(buf
, objdir
, len
);
200 fill_sha1_path(buf
+ len
+ 1, sha1
);
205 * Return the name of the pack or index file with the specified sha1
206 * in its filename. *base and *name are scratch space that must be
207 * provided by the caller. which should be "pack" or "idx".
209 static char *sha1_get_pack_name(const unsigned char *sha1
,
210 char **name
, char **base
, const char *which
)
212 static const char hex
[] = "0123456789abcdef";
217 const char *sha1_file_directory
= get_object_directory();
218 int len
= strlen(sha1_file_directory
);
219 *base
= xmalloc(len
+ 60);
220 sprintf(*base
, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
221 sha1_file_directory
, which
);
222 *name
= *base
+ len
+ 11;
227 for (i
= 0; i
< 20; i
++) {
228 unsigned int val
= *sha1
++;
229 *buf
++ = hex
[val
>> 4];
230 *buf
++ = hex
[val
& 0xf];
236 char *sha1_pack_name(const unsigned char *sha1
)
238 static char *name
, *base
;
240 return sha1_get_pack_name(sha1
, &name
, &base
, "pack");
243 char *sha1_pack_index_name(const unsigned char *sha1
)
245 static char *name
, *base
;
247 return sha1_get_pack_name(sha1
, &name
, &base
, "idx");
250 struct alternate_object_database
*alt_odb_list
;
251 static struct alternate_object_database
**alt_odb_tail
;
254 * Prepare alternate object database registry.
256 * The variable alt_odb_list points at the list of struct
257 * alternate_object_database. The elements on this list come from
258 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
259 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
260 * whose contents is similar to that environment variable but can be
261 * LF separated. Its base points at a statically allocated buffer that
262 * contains "/the/directory/corresponding/to/.git/objects/...", while
263 * its name points just after the slash at the end of ".git/objects/"
264 * in the example above, and has enough space to hold 40-byte hex
265 * SHA1, an extra slash for the first level indirection, and the
268 static int link_alt_odb_entry(const char *entry
, const char *relative_base
,
269 int depth
, const char *normalized_objdir
)
271 struct alternate_object_database
*ent
;
272 struct alternate_object_database
*alt
;
274 struct strbuf pathbuf
= STRBUF_INIT
;
276 if (!is_absolute_path(entry
) && relative_base
) {
277 strbuf_addstr(&pathbuf
, real_path(relative_base
));
278 strbuf_addch(&pathbuf
, '/');
280 strbuf_addstr(&pathbuf
, entry
);
282 normalize_path_copy(pathbuf
.buf
, pathbuf
.buf
);
284 pfxlen
= strlen(pathbuf
.buf
);
287 * The trailing slash after the directory name is given by
288 * this function at the end. Remove duplicates.
290 while (pfxlen
&& pathbuf
.buf
[pfxlen
-1] == '/')
293 entlen
= pfxlen
+ 43; /* '/' + 2 hex + '/' + 38 hex + NUL */
294 ent
= xmalloc(sizeof(*ent
) + entlen
);
295 memcpy(ent
->base
, pathbuf
.buf
, pfxlen
);
296 strbuf_release(&pathbuf
);
298 ent
->name
= ent
->base
+ pfxlen
+ 1;
299 ent
->base
[pfxlen
+ 3] = '/';
300 ent
->base
[pfxlen
] = ent
->base
[entlen
-1] = 0;
302 /* Detect cases where alternate disappeared */
303 if (!is_directory(ent
->base
)) {
304 error("object directory %s does not exist; "
305 "check .git/objects/info/alternates.",
311 /* Prevent the common mistake of listing the same
312 * thing twice, or object directory itself.
314 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
315 if (pfxlen
== alt
->name
- alt
->base
- 1 &&
316 !memcmp(ent
->base
, alt
->base
, pfxlen
)) {
321 if (!strcmp_icase(ent
->base
, normalized_objdir
)) {
326 /* add the alternate entry */
328 alt_odb_tail
= &(ent
->next
);
331 /* recursively add alternates */
332 read_info_alternates(ent
->base
, depth
+ 1);
334 ent
->base
[pfxlen
] = '/';
339 static void link_alt_odb_entries(const char *alt
, int len
, int sep
,
340 const char *relative_base
, int depth
)
342 struct string_list entries
= STRING_LIST_INIT_NODUP
;
345 struct strbuf objdirbuf
= STRBUF_INIT
;
348 error("%s: ignoring alternate object stores, nesting too deep.",
353 strbuf_add_absolute_path(&objdirbuf
, get_object_directory());
354 normalize_path_copy(objdirbuf
.buf
, objdirbuf
.buf
);
356 alt_copy
= xmemdupz(alt
, len
);
357 string_list_split_in_place(&entries
, alt_copy
, sep
, -1);
358 for (i
= 0; i
< entries
.nr
; i
++) {
359 const char *entry
= entries
.items
[i
].string
;
360 if (entry
[0] == '\0' || entry
[0] == '#')
362 if (!is_absolute_path(entry
) && depth
) {
363 error("%s: ignoring relative alternate object store %s",
364 relative_base
, entry
);
366 link_alt_odb_entry(entry
, relative_base
, depth
, objdirbuf
.buf
);
369 string_list_clear(&entries
, 0);
371 strbuf_release(&objdirbuf
);
374 void read_info_alternates(const char * relative_base
, int depth
)
379 const char alt_file_name
[] = "info/alternates";
380 /* Given that relative_base is no longer than PATH_MAX,
381 ensure that "path" has enough space to append "/", the
382 file name, "info/alternates", and a trailing NUL. */
383 char path
[PATH_MAX
+ 1 + sizeof alt_file_name
];
386 sprintf(path
, "%s/%s", relative_base
, alt_file_name
);
387 fd
= git_open_noatime(path
);
390 if (fstat(fd
, &st
) || (st
.st_size
== 0)) {
394 mapsz
= xsize_t(st
.st_size
);
395 map
= xmmap(NULL
, mapsz
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
398 link_alt_odb_entries(map
, mapsz
, '\n', relative_base
, depth
);
403 void add_to_alternates_file(const char *reference
)
405 struct lock_file
*lock
= xcalloc(1, sizeof(struct lock_file
));
406 int fd
= hold_lock_file_for_append(lock
, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR
);
407 const char *alt
= mkpath("%s\n", reference
);
408 write_or_die(fd
, alt
, strlen(alt
));
409 if (commit_lock_file(lock
))
410 die("could not close alternates file");
412 link_alt_odb_entries(alt
, strlen(alt
), '\n', NULL
, 0);
415 void foreach_alt_odb(alt_odb_fn fn
, void *cb
)
417 struct alternate_object_database
*ent
;
420 for (ent
= alt_odb_list
; ent
; ent
= ent
->next
)
425 void prepare_alt_odb(void)
432 alt
= getenv(ALTERNATE_DB_ENVIRONMENT
);
435 alt_odb_tail
= &alt_odb_list
;
436 link_alt_odb_entries(alt
, strlen(alt
), PATH_SEP
, NULL
, 0);
438 read_info_alternates(get_object_directory(), 0);
441 static int has_loose_object_local(const unsigned char *sha1
)
443 return !access(sha1_file_name(sha1
), F_OK
);
446 int has_loose_object_nonlocal(const unsigned char *sha1
)
448 struct alternate_object_database
*alt
;
450 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
451 fill_sha1_path(alt
->name
, sha1
);
452 if (!access(alt
->base
, F_OK
))
458 static int has_loose_object(const unsigned char *sha1
)
460 return has_loose_object_local(sha1
) ||
461 has_loose_object_nonlocal(sha1
);
464 static unsigned int pack_used_ctr
;
465 static unsigned int pack_mmap_calls
;
466 static unsigned int peak_pack_open_windows
;
467 static unsigned int pack_open_windows
;
468 static unsigned int pack_open_fds
;
469 static unsigned int pack_max_fds
;
470 static size_t peak_pack_mapped
;
471 static size_t pack_mapped
;
472 struct packed_git
*packed_git
;
474 void pack_report(void)
477 "pack_report: getpagesize() = %10" SZ_FMT
"\n"
478 "pack_report: core.packedGitWindowSize = %10" SZ_FMT
"\n"
479 "pack_report: core.packedGitLimit = %10" SZ_FMT
"\n",
480 sz_fmt(getpagesize()),
481 sz_fmt(packed_git_window_size
),
482 sz_fmt(packed_git_limit
));
484 "pack_report: pack_used_ctr = %10u\n"
485 "pack_report: pack_mmap_calls = %10u\n"
486 "pack_report: pack_open_windows = %10u / %10u\n"
487 "pack_report: pack_mapped = "
488 "%10" SZ_FMT
" / %10" SZ_FMT
"\n",
491 pack_open_windows
, peak_pack_open_windows
,
492 sz_fmt(pack_mapped
), sz_fmt(peak_pack_mapped
));
496 * Open and mmap the index file at path, perform a couple of
497 * consistency checks, then record its information to p. Return 0 on
500 static int check_packed_git_idx(const char *path
, struct packed_git
*p
)
503 struct pack_idx_header
*hdr
;
505 uint32_t version
, nr
, i
, *index
;
506 int fd
= git_open_noatime(path
);
511 if (fstat(fd
, &st
)) {
515 idx_size
= xsize_t(st
.st_size
);
516 if (idx_size
< 4 * 256 + 20 + 20) {
518 return error("index file %s is too small", path
);
520 idx_map
= xmmap(NULL
, idx_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
524 if (hdr
->idx_signature
== htonl(PACK_IDX_SIGNATURE
)) {
525 version
= ntohl(hdr
->idx_version
);
526 if (version
< 2 || version
> 2) {
527 munmap(idx_map
, idx_size
);
528 return error("index file %s is version %"PRIu32
529 " and is not supported by this binary"
530 " (try upgrading GIT to a newer version)",
539 index
+= 2; /* skip index header */
540 for (i
= 0; i
< 256; i
++) {
541 uint32_t n
= ntohl(index
[i
]);
543 munmap(idx_map
, idx_size
);
544 return error("non-monotonic index %s", path
);
552 * - 256 index entries 4 bytes each
553 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
554 * - 20-byte SHA1 of the packfile
555 * - 20-byte SHA1 file checksum
557 if (idx_size
!= 4*256 + nr
* 24 + 20 + 20) {
558 munmap(idx_map
, idx_size
);
559 return error("wrong index v1 file size in %s", path
);
561 } else if (version
== 2) {
564 * - 8 bytes of header
565 * - 256 index entries 4 bytes each
566 * - 20-byte sha1 entry * nr
567 * - 4-byte crc entry * nr
568 * - 4-byte offset entry * nr
569 * - 20-byte SHA1 of the packfile
570 * - 20-byte SHA1 file checksum
571 * And after the 4-byte offset table might be a
572 * variable sized table containing 8-byte entries
573 * for offsets larger than 2^31.
575 unsigned long min_size
= 8 + 4*256 + nr
*(20 + 4 + 4) + 20 + 20;
576 unsigned long max_size
= min_size
;
578 max_size
+= (nr
- 1)*8;
579 if (idx_size
< min_size
|| idx_size
> max_size
) {
580 munmap(idx_map
, idx_size
);
581 return error("wrong index v2 file size in %s", path
);
583 if (idx_size
!= min_size
&&
585 * make sure we can deal with large pack offsets.
586 * 31-bit signed offset won't be enough, neither
587 * 32-bit unsigned one will be.
589 (sizeof(off_t
) <= 4)) {
590 munmap(idx_map
, idx_size
);
591 return error("pack too large for current definition of off_t in %s", path
);
595 p
->index_version
= version
;
596 p
->index_data
= idx_map
;
597 p
->index_size
= idx_size
;
602 int open_pack_index(struct packed_git
*p
)
610 idx_name
= xstrdup(p
->pack_name
);
611 strcpy(idx_name
+ strlen(idx_name
) - strlen(".pack"), ".idx");
612 ret
= check_packed_git_idx(idx_name
, p
);
617 static void scan_windows(struct packed_git
*p
,
618 struct packed_git
**lru_p
,
619 struct pack_window
**lru_w
,
620 struct pack_window
**lru_l
)
622 struct pack_window
*w
, *w_l
;
624 for (w_l
= NULL
, w
= p
->windows
; w
; w
= w
->next
) {
626 if (!*lru_w
|| w
->last_used
< (*lru_w
)->last_used
) {
636 static int unuse_one_window(struct packed_git
*current
)
638 struct packed_git
*p
, *lru_p
= NULL
;
639 struct pack_window
*lru_w
= NULL
, *lru_l
= NULL
;
642 scan_windows(current
, &lru_p
, &lru_w
, &lru_l
);
643 for (p
= packed_git
; p
; p
= p
->next
)
644 scan_windows(p
, &lru_p
, &lru_w
, &lru_l
);
646 munmap(lru_w
->base
, lru_w
->len
);
647 pack_mapped
-= lru_w
->len
;
649 lru_l
->next
= lru_w
->next
;
651 lru_p
->windows
= lru_w
->next
;
659 void release_pack_memory(size_t need
)
661 size_t cur
= pack_mapped
;
662 while (need
>= (cur
- pack_mapped
) && unuse_one_window(NULL
))
666 static void mmap_limit_check(size_t length
)
668 static ssize_t limit
= -1;
670 const char *env
= getenv("GIT_MMAP_LIMIT");
671 limit
= env
? atol(env
) * 1024 : 0;
673 if (limit
&& length
> limit
)
674 die("attempting to mmap %"PRIuMAX
" over limit %"PRIuMAX
,
675 (uintmax_t)length
, (uintmax_t)limit
);
678 void *xmmap(void *start
, size_t length
,
679 int prot
, int flags
, int fd
, off_t offset
)
683 mmap_limit_check(length
);
684 ret
= mmap(start
, length
, prot
, flags
, fd
, offset
);
685 if (ret
== MAP_FAILED
) {
688 release_pack_memory(length
);
689 ret
= mmap(start
, length
, prot
, flags
, fd
, offset
);
690 if (ret
== MAP_FAILED
)
691 die_errno("Out of memory? mmap failed");
696 void close_pack_windows(struct packed_git
*p
)
699 struct pack_window
*w
= p
->windows
;
702 die("pack '%s' still has open windows to it",
704 munmap(w
->base
, w
->len
);
705 pack_mapped
-= w
->len
;
707 p
->windows
= w
->next
;
713 * The LRU pack is the one with the oldest MRU window, preferring packs
714 * with no used windows, or the oldest mtime if it has no windows allocated.
716 static void find_lru_pack(struct packed_git
*p
, struct packed_git
**lru_p
, struct pack_window
**mru_w
, int *accept_windows_inuse
)
718 struct pack_window
*w
, *this_mru_w
;
719 int has_windows_inuse
= 0;
722 * Reject this pack if it has windows and the previously selected
723 * one does not. If this pack does not have windows, reject
724 * it if the pack file is newer than the previously selected one.
726 if (*lru_p
&& !*mru_w
&& (p
->windows
|| p
->mtime
> (*lru_p
)->mtime
))
729 for (w
= this_mru_w
= p
->windows
; w
; w
= w
->next
) {
731 * Reject this pack if any of its windows are in use,
732 * but the previously selected pack did not have any
733 * inuse windows. Otherwise, record that this pack
734 * has windows in use.
737 if (*accept_windows_inuse
)
738 has_windows_inuse
= 1;
743 if (w
->last_used
> this_mru_w
->last_used
)
747 * Reject this pack if it has windows that have been
748 * used more recently than the previously selected pack.
749 * If the previously selected pack had windows inuse and
750 * we have not encountered a window in this pack that is
751 * inuse, skip this check since we prefer a pack with no
752 * inuse windows to one that has inuse windows.
754 if (*mru_w
&& *accept_windows_inuse
== has_windows_inuse
&&
755 this_mru_w
->last_used
> (*mru_w
)->last_used
)
764 *accept_windows_inuse
= has_windows_inuse
;
767 static int close_one_pack(void)
769 struct packed_git
*p
, *lru_p
= NULL
;
770 struct pack_window
*mru_w
= NULL
;
771 int accept_windows_inuse
= 1;
773 for (p
= packed_git
; p
; p
= p
->next
) {
774 if (p
->pack_fd
== -1)
776 find_lru_pack(p
, &lru_p
, &mru_w
, &accept_windows_inuse
);
780 close(lru_p
->pack_fd
);
789 void unuse_pack(struct pack_window
**w_cursor
)
791 struct pack_window
*w
= *w_cursor
;
798 void close_pack_index(struct packed_git
*p
)
801 munmap((void *)p
->index_data
, p
->index_size
);
802 p
->index_data
= NULL
;
807 * This is used by git-repack in case a newly created pack happens to
808 * contain the same set of objects as an existing one. In that case
809 * the resulting file might be different even if its name would be the
810 * same. It is best to close any reference to the old pack before it is
811 * replaced on disk. Of course no index pointers or windows for given pack
812 * must subsist at this point. If ever objects from this pack are requested
813 * again, the new version of the pack will be reinitialized through
814 * reprepare_packed_git().
816 void free_pack_by_name(const char *pack_name
)
818 struct packed_git
*p
, **pp
= &packed_git
;
822 if (strcmp(pack_name
, p
->pack_name
) == 0) {
823 clear_delta_base_cache();
824 close_pack_windows(p
);
825 if (p
->pack_fd
!= -1) {
830 free(p
->bad_object_sha1
);
832 if (last_found_pack
== p
)
833 last_found_pack
= NULL
;
841 static unsigned int get_max_fd_limit(void)
847 if (!getrlimit(RLIMIT_NOFILE
, &lim
))
854 long open_max
= sysconf(_SC_OPEN_MAX
);
858 * Otherwise, we got -1 for one of the two
861 * (1) sysconf() did not understand _SC_OPEN_MAX
862 * and signaled an error with -1; or
863 * (2) sysconf() said there is no limit.
865 * We _could_ clear errno before calling sysconf() to
866 * tell these two cases apart and return a huge number
867 * in the latter case to let the caller cap it to a
868 * value that is not so selfish, but letting the
869 * fallback OPEN_MAX codepath take care of these cases
878 return 1; /* see the caller ;-) */
883 * Do not call this directly as this leaks p->pack_fd on error return;
884 * call open_packed_git() instead.
886 static int open_packed_git_1(struct packed_git
*p
)
889 struct pack_header hdr
;
890 unsigned char sha1
[20];
891 unsigned char *idx_sha1
;
894 if (!p
->index_data
&& open_pack_index(p
))
895 return error("packfile %s index unavailable", p
->pack_name
);
898 unsigned int max_fds
= get_max_fd_limit();
900 /* Save 3 for stdin/stdout/stderr, 22 for work */
902 pack_max_fds
= max_fds
- 25;
907 while (pack_max_fds
<= pack_open_fds
&& close_one_pack())
910 p
->pack_fd
= git_open_noatime(p
->pack_name
);
911 if (p
->pack_fd
< 0 || fstat(p
->pack_fd
, &st
))
915 /* If we created the struct before we had the pack we lack size. */
917 if (!S_ISREG(st
.st_mode
))
918 return error("packfile %s not a regular file", p
->pack_name
);
919 p
->pack_size
= st
.st_size
;
920 } else if (p
->pack_size
!= st
.st_size
)
921 return error("packfile %s size changed", p
->pack_name
);
923 /* We leave these file descriptors open with sliding mmap;
924 * there is no point keeping them open across exec(), though.
926 fd_flag
= fcntl(p
->pack_fd
, F_GETFD
, 0);
928 return error("cannot determine file descriptor flags");
929 fd_flag
|= FD_CLOEXEC
;
930 if (fcntl(p
->pack_fd
, F_SETFD
, fd_flag
) == -1)
931 return error("cannot set FD_CLOEXEC");
933 /* Verify we recognize this pack file format. */
934 if (read_in_full(p
->pack_fd
, &hdr
, sizeof(hdr
)) != sizeof(hdr
))
935 return error("file %s is far too short to be a packfile", p
->pack_name
);
936 if (hdr
.hdr_signature
!= htonl(PACK_SIGNATURE
))
937 return error("file %s is not a GIT packfile", p
->pack_name
);
938 if (!pack_version_ok(hdr
.hdr_version
))
939 return error("packfile %s is version %"PRIu32
" and not"
940 " supported (try upgrading GIT to a newer version)",
941 p
->pack_name
, ntohl(hdr
.hdr_version
));
943 /* Verify the pack matches its index. */
944 if (p
->num_objects
!= ntohl(hdr
.hdr_entries
))
945 return error("packfile %s claims to have %"PRIu32
" objects"
946 " while index indicates %"PRIu32
" objects",
947 p
->pack_name
, ntohl(hdr
.hdr_entries
),
949 if (lseek(p
->pack_fd
, p
->pack_size
- sizeof(sha1
), SEEK_SET
) == -1)
950 return error("end of packfile %s is unavailable", p
->pack_name
);
951 if (read_in_full(p
->pack_fd
, sha1
, sizeof(sha1
)) != sizeof(sha1
))
952 return error("packfile %s signature is unavailable", p
->pack_name
);
953 idx_sha1
= ((unsigned char *)p
->index_data
) + p
->index_size
- 40;
954 if (hashcmp(sha1
, idx_sha1
))
955 return error("packfile %s does not match index", p
->pack_name
);
959 static int open_packed_git(struct packed_git
*p
)
961 if (!open_packed_git_1(p
))
963 if (p
->pack_fd
!= -1) {
971 static int in_window(struct pack_window
*win
, off_t offset
)
973 /* We must promise at least 20 bytes (one hash) after the
974 * offset is available from this window, otherwise the offset
975 * is not actually in this window and a different window (which
976 * has that one hash excess) must be used. This is to support
977 * the object header and delta base parsing routines below.
979 off_t win_off
= win
->offset
;
980 return win_off
<= offset
981 && (offset
+ 20) <= (win_off
+ win
->len
);
984 unsigned char *use_pack(struct packed_git
*p
,
985 struct pack_window
**w_cursor
,
989 struct pack_window
*win
= *w_cursor
;
991 /* Since packfiles end in a hash of their content and it's
992 * pointless to ask for an offset into the middle of that
993 * hash, and the in_window function above wouldn't match
994 * don't allow an offset too close to the end of the file.
996 if (!p
->pack_size
&& p
->pack_fd
== -1 && open_packed_git(p
))
997 die("packfile %s cannot be accessed", p
->pack_name
);
998 if (offset
> (p
->pack_size
- 20))
999 die("offset beyond end of packfile (truncated pack?)");
1001 if (!win
|| !in_window(win
, offset
)) {
1004 for (win
= p
->windows
; win
; win
= win
->next
) {
1005 if (in_window(win
, offset
))
1009 size_t window_align
= packed_git_window_size
/ 2;
1012 if (p
->pack_fd
== -1 && open_packed_git(p
))
1013 die("packfile %s cannot be accessed", p
->pack_name
);
1015 win
= xcalloc(1, sizeof(*win
));
1016 win
->offset
= (offset
/ window_align
) * window_align
;
1017 len
= p
->pack_size
- win
->offset
;
1018 if (len
> packed_git_window_size
)
1019 len
= packed_git_window_size
;
1020 win
->len
= (size_t)len
;
1021 pack_mapped
+= win
->len
;
1022 while (packed_git_limit
< pack_mapped
1023 && unuse_one_window(p
))
1025 win
->base
= xmmap(NULL
, win
->len
,
1026 PROT_READ
, MAP_PRIVATE
,
1027 p
->pack_fd
, win
->offset
);
1028 if (win
->base
== MAP_FAILED
)
1029 die("packfile %s cannot be mapped: %s",
1032 if (!win
->offset
&& win
->len
== p
->pack_size
1033 && !p
->do_not_close
) {
1039 pack_open_windows
++;
1040 if (pack_mapped
> peak_pack_mapped
)
1041 peak_pack_mapped
= pack_mapped
;
1042 if (pack_open_windows
> peak_pack_open_windows
)
1043 peak_pack_open_windows
= pack_open_windows
;
1044 win
->next
= p
->windows
;
1048 if (win
!= *w_cursor
) {
1049 win
->last_used
= pack_used_ctr
++;
1053 offset
-= win
->offset
;
1055 *left
= win
->len
- xsize_t(offset
);
1056 return win
->base
+ offset
;
1059 static struct packed_git
*alloc_packed_git(int extra
)
1061 struct packed_git
*p
= xmalloc(sizeof(*p
) + extra
);
1062 memset(p
, 0, sizeof(*p
));
1067 static void try_to_free_pack_memory(size_t size
)
1069 release_pack_memory(size
);
1072 struct packed_git
*add_packed_git(const char *path
, int path_len
, int local
)
1074 static int have_set_try_to_free_routine
;
1076 struct packed_git
*p
= alloc_packed_git(path_len
+ 2);
1078 if (!have_set_try_to_free_routine
) {
1079 have_set_try_to_free_routine
= 1;
1080 set_try_to_free_routine(try_to_free_pack_memory
);
1084 * Make sure a corresponding .pack file exists and that
1085 * the index looks sane.
1087 path_len
-= strlen(".idx");
1092 memcpy(p
->pack_name
, path
, path_len
);
1094 strcpy(p
->pack_name
+ path_len
, ".keep");
1095 if (!access(p
->pack_name
, F_OK
))
1098 strcpy(p
->pack_name
+ path_len
, ".pack");
1099 if (stat(p
->pack_name
, &st
) || !S_ISREG(st
.st_mode
)) {
1104 /* ok, it looks sane as far as we can check without
1105 * actually mapping the pack file.
1107 p
->pack_size
= st
.st_size
;
1108 p
->pack_local
= local
;
1109 p
->mtime
= st
.st_mtime
;
1110 if (path_len
< 40 || get_sha1_hex(path
+ path_len
- 40, p
->sha1
))
1115 struct packed_git
*parse_pack_index(unsigned char *sha1
, const char *idx_path
)
1117 const char *path
= sha1_pack_name(sha1
);
1118 struct packed_git
*p
= alloc_packed_git(strlen(path
) + 1);
1120 strcpy(p
->pack_name
, path
);
1121 hashcpy(p
->sha1
, sha1
);
1122 if (check_packed_git_idx(idx_path
, p
)) {
1130 void install_packed_git(struct packed_git
*pack
)
1132 if (pack
->pack_fd
!= -1)
1135 pack
->next
= packed_git
;
1139 void (*report_garbage
)(const char *desc
, const char *path
);
1141 static void report_helper(const struct string_list
*list
,
1142 int seen_bits
, int first
, int last
)
1145 switch (seen_bits
) {
1147 msg
= "no corresponding .idx or .pack";
1150 msg
= "no corresponding .idx";
1153 msg
= "no corresponding .pack";
1158 for (; first
< last
; first
++)
1159 report_garbage(msg
, list
->items
[first
].string
);
1162 static void report_pack_garbage(struct string_list
*list
)
1164 int i
, baselen
= -1, first
= 0, seen_bits
= 0;
1166 if (!report_garbage
)
1169 sort_string_list(list
);
1171 for (i
= 0; i
< list
->nr
; i
++) {
1172 const char *path
= list
->items
[i
].string
;
1173 if (baselen
!= -1 &&
1174 strncmp(path
, list
->items
[first
].string
, baselen
)) {
1175 report_helper(list
, seen_bits
, first
, i
);
1179 if (baselen
== -1) {
1180 const char *dot
= strrchr(path
, '.');
1182 report_garbage("garbage found", path
);
1185 baselen
= dot
- path
+ 1;
1188 if (!strcmp(path
+ baselen
, "pack"))
1190 else if (!strcmp(path
+ baselen
, "idx"))
1193 report_helper(list
, seen_bits
, first
, list
->nr
);
1196 static void prepare_packed_git_one(char *objdir
, int local
)
1198 struct strbuf path
= STRBUF_INIT
;
1202 struct string_list garbage
= STRING_LIST_INIT_DUP
;
1204 strbuf_addstr(&path
, objdir
);
1205 strbuf_addstr(&path
, "/pack");
1206 dir
= opendir(path
.buf
);
1208 if (errno
!= ENOENT
)
1209 error("unable to open object pack directory: %s: %s",
1210 path
.buf
, strerror(errno
));
1211 strbuf_release(&path
);
1214 strbuf_addch(&path
, '/');
1215 dirnamelen
= path
.len
;
1216 while ((de
= readdir(dir
)) != NULL
) {
1217 struct packed_git
*p
;
1220 if (is_dot_or_dotdot(de
->d_name
))
1223 strbuf_setlen(&path
, dirnamelen
);
1224 strbuf_addstr(&path
, de
->d_name
);
1226 base_len
= path
.len
;
1227 if (strip_suffix_mem(path
.buf
, &base_len
, ".idx")) {
1228 /* Don't reopen a pack we already have. */
1229 for (p
= packed_git
; p
; p
= p
->next
) {
1231 if (strip_suffix(p
->pack_name
, ".pack", &len
) &&
1233 !memcmp(p
->pack_name
, path
.buf
, len
))
1238 * See if it really is a valid .idx file with
1239 * corresponding .pack file that we can map.
1241 (p
= add_packed_git(path
.buf
, path
.len
, local
)) != NULL
)
1242 install_packed_git(p
);
1245 if (!report_garbage
)
1248 if (ends_with(de
->d_name
, ".idx") ||
1249 ends_with(de
->d_name
, ".pack") ||
1250 ends_with(de
->d_name
, ".bitmap") ||
1251 ends_with(de
->d_name
, ".keep"))
1252 string_list_append(&garbage
, path
.buf
);
1254 report_garbage("garbage found", path
.buf
);
1257 report_pack_garbage(&garbage
);
1258 string_list_clear(&garbage
, 0);
1259 strbuf_release(&path
);
1262 static int sort_pack(const void *a_
, const void *b_
)
1264 struct packed_git
*a
= *((struct packed_git
**)a_
);
1265 struct packed_git
*b
= *((struct packed_git
**)b_
);
1269 * Local packs tend to contain objects specific to our
1270 * variant of the project than remote ones. In addition,
1271 * remote ones could be on a network mounted filesystem.
1272 * Favor local ones for these reasons.
1274 st
= a
->pack_local
- b
->pack_local
;
1279 * Younger packs tend to contain more recent objects,
1280 * and more recent objects tend to get accessed more
1283 if (a
->mtime
< b
->mtime
)
1285 else if (a
->mtime
== b
->mtime
)
1290 static void rearrange_packed_git(void)
1292 struct packed_git
**ary
, *p
;
1295 for (n
= 0, p
= packed_git
; p
; p
= p
->next
)
1300 /* prepare an array of packed_git for easier sorting */
1301 ary
= xcalloc(n
, sizeof(struct packed_git
*));
1302 for (n
= 0, p
= packed_git
; p
; p
= p
->next
)
1305 qsort(ary
, n
, sizeof(struct packed_git
*), sort_pack
);
1307 /* link them back again */
1308 for (i
= 0; i
< n
- 1; i
++)
1309 ary
[i
]->next
= ary
[i
+ 1];
1310 ary
[n
- 1]->next
= NULL
;
1311 packed_git
= ary
[0];
1316 static int prepare_packed_git_run_once
= 0;
1317 void prepare_packed_git(void)
1319 struct alternate_object_database
*alt
;
1321 if (prepare_packed_git_run_once
)
1323 prepare_packed_git_one(get_object_directory(), 1);
1325 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
1327 prepare_packed_git_one(alt
->base
, 0);
1328 alt
->name
[-1] = '/';
1330 rearrange_packed_git();
1331 prepare_packed_git_run_once
= 1;
1334 void reprepare_packed_git(void)
1336 prepare_packed_git_run_once
= 0;
1337 prepare_packed_git();
1340 static void mark_bad_packed_object(struct packed_git
*p
,
1341 const unsigned char *sha1
)
1344 for (i
= 0; i
< p
->num_bad_objects
; i
++)
1345 if (!hashcmp(sha1
, p
->bad_object_sha1
+ 20 * i
))
1347 p
->bad_object_sha1
= xrealloc(p
->bad_object_sha1
, 20 * (p
->num_bad_objects
+ 1));
1348 hashcpy(p
->bad_object_sha1
+ 20 * p
->num_bad_objects
, sha1
);
1349 p
->num_bad_objects
++;
1352 static const struct packed_git
*has_packed_and_bad(const unsigned char *sha1
)
1354 struct packed_git
*p
;
1357 for (p
= packed_git
; p
; p
= p
->next
)
1358 for (i
= 0; i
< p
->num_bad_objects
; i
++)
1359 if (!hashcmp(sha1
, p
->bad_object_sha1
+ 20 * i
))
1365 * With an in-core object data in "map", rehash it to make sure the
1366 * object name actually matches "sha1" to detect object corruption.
1367 * With "map" == NULL, try reading the object named with "sha1" using
1368 * the streaming interface and rehash it to do the same.
1370 int check_sha1_signature(const unsigned char *sha1
, void *map
,
1371 unsigned long size
, const char *type
)
1373 unsigned char real_sha1
[20];
1374 enum object_type obj_type
;
1375 struct git_istream
*st
;
1381 hash_sha1_file(map
, size
, type
, real_sha1
);
1382 return hashcmp(sha1
, real_sha1
) ? -1 : 0;
1385 st
= open_istream(sha1
, &obj_type
, &size
, NULL
);
1389 /* Generate the header */
1390 hdrlen
= sprintf(hdr
, "%s %lu", typename(obj_type
), size
) + 1;
1394 git_SHA1_Update(&c
, hdr
, hdrlen
);
1396 char buf
[1024 * 16];
1397 ssize_t readlen
= read_istream(st
, buf
, sizeof(buf
));
1405 git_SHA1_Update(&c
, buf
, readlen
);
1407 git_SHA1_Final(real_sha1
, &c
);
1409 return hashcmp(sha1
, real_sha1
) ? -1 : 0;
1412 int git_open_noatime(const char *name
)
1414 static int sha1_file_open_flag
= O_NOATIME
;
1417 int fd
= open(name
, O_RDONLY
| sha1_file_open_flag
);
1421 /* Might the failure be due to O_NOATIME? */
1422 if (errno
!= ENOENT
&& sha1_file_open_flag
) {
1423 sha1_file_open_flag
= 0;
1431 static int stat_sha1_file(const unsigned char *sha1
, struct stat
*st
)
1433 struct alternate_object_database
*alt
;
1435 if (!lstat(sha1_file_name(sha1
), st
))
1440 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
1441 fill_sha1_path(alt
->name
, sha1
);
1442 if (!lstat(alt
->base
, st
))
1449 static int open_sha1_file(const unsigned char *sha1
)
1452 struct alternate_object_database
*alt
;
1453 int most_interesting_errno
;
1455 fd
= git_open_noatime(sha1_file_name(sha1
));
1458 most_interesting_errno
= errno
;
1461 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
1462 fill_sha1_path(alt
->name
, sha1
);
1463 fd
= git_open_noatime(alt
->base
);
1466 if (most_interesting_errno
== ENOENT
)
1467 most_interesting_errno
= errno
;
1469 errno
= most_interesting_errno
;
1473 void *map_sha1_file(const unsigned char *sha1
, unsigned long *size
)
1478 fd
= open_sha1_file(sha1
);
1483 if (!fstat(fd
, &st
)) {
1484 *size
= xsize_t(st
.st_size
);
1486 /* mmap() is forbidden on empty files */
1487 error("object file %s is empty", sha1_file_name(sha1
));
1490 map
= xmmap(NULL
, *size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
1497 unsigned long unpack_object_header_buffer(const unsigned char *buf
,
1498 unsigned long len
, enum object_type
*type
, unsigned long *sizep
)
1501 unsigned long size
, c
;
1502 unsigned long used
= 0;
1505 *type
= (c
>> 4) & 7;
1509 if (len
<= used
|| bitsizeof(long) <= shift
) {
1510 error("bad object header");
1515 size
+= (c
& 0x7f) << shift
;
1522 int unpack_sha1_header(git_zstream
*stream
, unsigned char *map
, unsigned long mapsize
, void *buffer
, unsigned long bufsiz
)
1524 /* Get the data stream */
1525 memset(stream
, 0, sizeof(*stream
));
1526 stream
->next_in
= map
;
1527 stream
->avail_in
= mapsize
;
1528 stream
->next_out
= buffer
;
1529 stream
->avail_out
= bufsiz
;
1531 git_inflate_init(stream
);
1532 return git_inflate(stream
, 0);
1535 static void *unpack_sha1_rest(git_zstream
*stream
, void *buffer
, unsigned long size
, const unsigned char *sha1
)
1537 int bytes
= strlen(buffer
) + 1;
1538 unsigned char *buf
= xmallocz(size
);
1542 n
= stream
->total_out
- bytes
;
1545 memcpy(buf
, (char *) buffer
+ bytes
, n
);
1547 if (bytes
<= size
) {
1549 * The above condition must be (bytes <= size), not
1550 * (bytes < size). In other words, even though we
1551 * expect no more output and set avail_out to zero,
1552 * the input zlib stream may have bytes that express
1553 * "this concludes the stream", and we *do* want to
1556 * Otherwise we would not be able to test that we
1557 * consumed all the input to reach the expected size;
1558 * we also want to check that zlib tells us that all
1559 * went well with status == Z_STREAM_END at the end.
1561 stream
->next_out
= buf
+ bytes
;
1562 stream
->avail_out
= size
- bytes
;
1563 while (status
== Z_OK
)
1564 status
= git_inflate(stream
, Z_FINISH
);
1566 if (status
== Z_STREAM_END
&& !stream
->avail_in
) {
1567 git_inflate_end(stream
);
1572 error("corrupt loose object '%s'", sha1_to_hex(sha1
));
1573 else if (stream
->avail_in
)
1574 error("garbage at end of loose object '%s'",
1581 * We used to just use "sscanf()", but that's actually way
1582 * too permissive for what we want to check. So do an anal
1583 * object header parse by hand.
1585 int parse_sha1_header(const char *hdr
, unsigned long *sizep
)
1592 * The type can be at most ten bytes (including the
1593 * terminating '\0' that we add), and is followed by
1602 if (i
>= sizeof(type
))
1608 * The length must follow immediately, and be in canonical
1609 * decimal format (ie "010" is not valid).
1611 size
= *hdr
++ - '0';
1616 unsigned long c
= *hdr
- '0';
1620 size
= size
* 10 + c
;
1626 * The length must be followed by a zero byte
1628 return *hdr
? -1 : type_from_string(type
);
1631 static void *unpack_sha1_file(void *map
, unsigned long mapsize
, enum object_type
*type
, unsigned long *size
, const unsigned char *sha1
)
1637 ret
= unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
));
1638 if (ret
< Z_OK
|| (*type
= parse_sha1_header(hdr
, size
)) < 0)
1641 return unpack_sha1_rest(&stream
, hdr
, *size
, sha1
);
1644 unsigned long get_size_from_delta(struct packed_git
*p
,
1645 struct pack_window
**w_curs
,
1648 const unsigned char *data
;
1649 unsigned char delta_head
[20], *in
;
1653 memset(&stream
, 0, sizeof(stream
));
1654 stream
.next_out
= delta_head
;
1655 stream
.avail_out
= sizeof(delta_head
);
1657 git_inflate_init(&stream
);
1659 in
= use_pack(p
, w_curs
, curpos
, &stream
.avail_in
);
1660 stream
.next_in
= in
;
1661 st
= git_inflate(&stream
, Z_FINISH
);
1662 curpos
+= stream
.next_in
- in
;
1663 } while ((st
== Z_OK
|| st
== Z_BUF_ERROR
) &&
1664 stream
.total_out
< sizeof(delta_head
));
1665 git_inflate_end(&stream
);
1666 if ((st
!= Z_STREAM_END
) && stream
.total_out
!= sizeof(delta_head
)) {
1667 error("delta data unpack-initial failed");
1671 /* Examine the initial part of the delta to figure out
1676 /* ignore base size */
1677 get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
1679 /* Read the result size */
1680 return get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
1683 static off_t
get_delta_base(struct packed_git
*p
,
1684 struct pack_window
**w_curs
,
1686 enum object_type type
,
1687 off_t delta_obj_offset
)
1689 unsigned char *base_info
= use_pack(p
, w_curs
, *curpos
, NULL
);
1692 /* use_pack() assured us we have [base_info, base_info + 20)
1693 * as a range that we can look at without walking off the
1694 * end of the mapped window. Its actually the hash size
1695 * that is assured. An OFS_DELTA longer than the hash size
1696 * is stupid, as then a REF_DELTA would be smaller to store.
1698 if (type
== OBJ_OFS_DELTA
) {
1700 unsigned char c
= base_info
[used
++];
1701 base_offset
= c
& 127;
1704 if (!base_offset
|| MSB(base_offset
, 7))
1705 return 0; /* overflow */
1706 c
= base_info
[used
++];
1707 base_offset
= (base_offset
<< 7) + (c
& 127);
1709 base_offset
= delta_obj_offset
- base_offset
;
1710 if (base_offset
<= 0 || base_offset
>= delta_obj_offset
)
1711 return 0; /* out of bound */
1713 } else if (type
== OBJ_REF_DELTA
) {
1714 /* The base entry _must_ be in the same pack */
1715 base_offset
= find_pack_entry_one(base_info
, p
);
1718 die("I am totally screwed");
1723 * Like get_delta_base above, but we return the sha1 instead of the pack
1724 * offset. This means it is cheaper for REF deltas (we do not have to do
1725 * the final object lookup), but more expensive for OFS deltas (we
1726 * have to load the revidx to convert the offset back into a sha1).
1728 static const unsigned char *get_delta_base_sha1(struct packed_git
*p
,
1729 struct pack_window
**w_curs
,
1731 enum object_type type
,
1732 off_t delta_obj_offset
)
1734 if (type
== OBJ_REF_DELTA
) {
1735 unsigned char *base
= use_pack(p
, w_curs
, curpos
, NULL
);
1737 } else if (type
== OBJ_OFS_DELTA
) {
1738 struct revindex_entry
*revidx
;
1739 off_t base_offset
= get_delta_base(p
, w_curs
, &curpos
,
1740 type
, delta_obj_offset
);
1745 revidx
= find_pack_revindex(p
, base_offset
);
1749 return nth_packed_object_sha1(p
, revidx
->nr
);
1754 int unpack_object_header(struct packed_git
*p
,
1755 struct pack_window
**w_curs
,
1757 unsigned long *sizep
)
1759 unsigned char *base
;
1762 enum object_type type
;
1764 /* use_pack() assures us we have [base, base + 20) available
1765 * as a range that we can look at. (Its actually the hash
1766 * size that is assured.) With our object header encoding
1767 * the maximum deflated object size is 2^137, which is just
1768 * insane, so we know won't exceed what we have been given.
1770 base
= use_pack(p
, w_curs
, *curpos
, &left
);
1771 used
= unpack_object_header_buffer(base
, left
, &type
, sizep
);
1780 static int retry_bad_packed_offset(struct packed_git
*p
, off_t obj_offset
)
1783 struct revindex_entry
*revidx
;
1784 const unsigned char *sha1
;
1785 revidx
= find_pack_revindex(p
, obj_offset
);
1788 sha1
= nth_packed_object_sha1(p
, revidx
->nr
);
1789 mark_bad_packed_object(p
, sha1
);
1790 type
= sha1_object_info(sha1
, NULL
);
1791 if (type
<= OBJ_NONE
)
1796 #define POI_STACK_PREALLOC 64
1798 static enum object_type
packed_to_object_type(struct packed_git
*p
,
1800 enum object_type type
,
1801 struct pack_window
**w_curs
,
1804 off_t small_poi_stack
[POI_STACK_PREALLOC
];
1805 off_t
*poi_stack
= small_poi_stack
;
1806 int poi_stack_nr
= 0, poi_stack_alloc
= POI_STACK_PREALLOC
;
1808 while (type
== OBJ_OFS_DELTA
|| type
== OBJ_REF_DELTA
) {
1811 /* Push the object we're going to leave behind */
1812 if (poi_stack_nr
>= poi_stack_alloc
&& poi_stack
== small_poi_stack
) {
1813 poi_stack_alloc
= alloc_nr(poi_stack_nr
);
1814 poi_stack
= xmalloc(sizeof(off_t
)*poi_stack_alloc
);
1815 memcpy(poi_stack
, small_poi_stack
, sizeof(off_t
)*poi_stack_nr
);
1817 ALLOC_GROW(poi_stack
, poi_stack_nr
+1, poi_stack_alloc
);
1819 poi_stack
[poi_stack_nr
++] = obj_offset
;
1820 /* If parsing the base offset fails, just unwind */
1821 base_offset
= get_delta_base(p
, w_curs
, &curpos
, type
, obj_offset
);
1824 curpos
= obj_offset
= base_offset
;
1825 type
= unpack_object_header(p
, w_curs
, &curpos
, &size
);
1826 if (type
<= OBJ_NONE
) {
1827 /* If getting the base itself fails, we first
1828 * retry the base, otherwise unwind */
1829 type
= retry_bad_packed_offset(p
, base_offset
);
1830 if (type
> OBJ_NONE
)
1844 error("unknown object type %i at offset %"PRIuMAX
" in %s",
1845 type
, (uintmax_t)obj_offset
, p
->pack_name
);
1850 if (poi_stack
!= small_poi_stack
)
1855 while (poi_stack_nr
) {
1856 obj_offset
= poi_stack
[--poi_stack_nr
];
1857 type
= retry_bad_packed_offset(p
, obj_offset
);
1858 if (type
> OBJ_NONE
)
1865 static int packed_object_info(struct packed_git
*p
, off_t obj_offset
,
1866 struct object_info
*oi
)
1868 struct pack_window
*w_curs
= NULL
;
1870 off_t curpos
= obj_offset
;
1871 enum object_type type
;
1874 * We always get the representation type, but only convert it to
1875 * a "real" type later if the caller is interested.
1877 type
= unpack_object_header(p
, &w_curs
, &curpos
, &size
);
1880 if (type
== OBJ_OFS_DELTA
|| type
== OBJ_REF_DELTA
) {
1881 off_t tmp_pos
= curpos
;
1882 off_t base_offset
= get_delta_base(p
, &w_curs
, &tmp_pos
,
1888 *oi
->sizep
= get_size_from_delta(p
, &w_curs
, tmp_pos
);
1889 if (*oi
->sizep
== 0) {
1898 if (oi
->disk_sizep
) {
1899 struct revindex_entry
*revidx
= find_pack_revindex(p
, obj_offset
);
1900 *oi
->disk_sizep
= revidx
[1].offset
- obj_offset
;
1904 *oi
->typep
= packed_to_object_type(p
, obj_offset
, type
, &w_curs
, curpos
);
1905 if (*oi
->typep
< 0) {
1911 if (oi
->delta_base_sha1
) {
1912 if (type
== OBJ_OFS_DELTA
|| type
== OBJ_REF_DELTA
) {
1913 const unsigned char *base
;
1915 base
= get_delta_base_sha1(p
, &w_curs
, curpos
,
1922 hashcpy(oi
->delta_base_sha1
, base
);
1924 hashclr(oi
->delta_base_sha1
);
1928 unuse_pack(&w_curs
);
1932 static void *unpack_compressed_entry(struct packed_git
*p
,
1933 struct pack_window
**w_curs
,
1939 unsigned char *buffer
, *in
;
1941 buffer
= xmallocz_gently(size
);
1944 memset(&stream
, 0, sizeof(stream
));
1945 stream
.next_out
= buffer
;
1946 stream
.avail_out
= size
+ 1;
1948 git_inflate_init(&stream
);
1950 in
= use_pack(p
, w_curs
, curpos
, &stream
.avail_in
);
1951 stream
.next_in
= in
;
1952 st
= git_inflate(&stream
, Z_FINISH
);
1953 if (!stream
.avail_out
)
1954 break; /* the payload is larger than it should be */
1955 curpos
+= stream
.next_in
- in
;
1956 } while (st
== Z_OK
|| st
== Z_BUF_ERROR
);
1957 git_inflate_end(&stream
);
1958 if ((st
!= Z_STREAM_END
) || stream
.total_out
!= size
) {
1966 #define MAX_DELTA_CACHE (256)
1968 static size_t delta_base_cached
;
1970 static struct delta_base_cache_lru_list
{
1971 struct delta_base_cache_lru_list
*prev
;
1972 struct delta_base_cache_lru_list
*next
;
1973 } delta_base_cache_lru
= { &delta_base_cache_lru
, &delta_base_cache_lru
};
1975 static struct delta_base_cache_entry
{
1976 struct delta_base_cache_lru_list lru
;
1978 struct packed_git
*p
;
1981 enum object_type type
;
1982 } delta_base_cache
[MAX_DELTA_CACHE
];
1984 static unsigned long pack_entry_hash(struct packed_git
*p
, off_t base_offset
)
1988 hash
= (unsigned long)p
+ (unsigned long)base_offset
;
1989 hash
+= (hash
>> 8) + (hash
>> 16);
1990 return hash
% MAX_DELTA_CACHE
;
1993 static struct delta_base_cache_entry
*
1994 get_delta_base_cache_entry(struct packed_git
*p
, off_t base_offset
)
1996 unsigned long hash
= pack_entry_hash(p
, base_offset
);
1997 return delta_base_cache
+ hash
;
2000 static int eq_delta_base_cache_entry(struct delta_base_cache_entry
*ent
,
2001 struct packed_git
*p
, off_t base_offset
)
2003 return (ent
->data
&& ent
->p
== p
&& ent
->base_offset
== base_offset
);
2006 static int in_delta_base_cache(struct packed_git
*p
, off_t base_offset
)
2008 struct delta_base_cache_entry
*ent
;
2009 ent
= get_delta_base_cache_entry(p
, base_offset
);
2010 return eq_delta_base_cache_entry(ent
, p
, base_offset
);
2013 static void clear_delta_base_cache_entry(struct delta_base_cache_entry
*ent
)
2016 ent
->lru
.next
->prev
= ent
->lru
.prev
;
2017 ent
->lru
.prev
->next
= ent
->lru
.next
;
2018 delta_base_cached
-= ent
->size
;
2021 static void *cache_or_unpack_entry(struct packed_git
*p
, off_t base_offset
,
2022 unsigned long *base_size
, enum object_type
*type
, int keep_cache
)
2024 struct delta_base_cache_entry
*ent
;
2027 ent
= get_delta_base_cache_entry(p
, base_offset
);
2029 if (!eq_delta_base_cache_entry(ent
, p
, base_offset
))
2030 return unpack_entry(p
, base_offset
, type
, base_size
);
2035 clear_delta_base_cache_entry(ent
);
2037 ret
= xmemdupz(ent
->data
, ent
->size
);
2039 *base_size
= ent
->size
;
2043 static inline void release_delta_base_cache(struct delta_base_cache_entry
*ent
)
2048 ent
->lru
.next
->prev
= ent
->lru
.prev
;
2049 ent
->lru
.prev
->next
= ent
->lru
.next
;
2050 delta_base_cached
-= ent
->size
;
2054 void clear_delta_base_cache(void)
2057 for (p
= 0; p
< MAX_DELTA_CACHE
; p
++)
2058 release_delta_base_cache(&delta_base_cache
[p
]);
2061 static void add_delta_base_cache(struct packed_git
*p
, off_t base_offset
,
2062 void *base
, unsigned long base_size
, enum object_type type
)
2064 unsigned long hash
= pack_entry_hash(p
, base_offset
);
2065 struct delta_base_cache_entry
*ent
= delta_base_cache
+ hash
;
2066 struct delta_base_cache_lru_list
*lru
;
2068 release_delta_base_cache(ent
);
2069 delta_base_cached
+= base_size
;
2071 for (lru
= delta_base_cache_lru
.next
;
2072 delta_base_cached
> delta_base_cache_limit
2073 && lru
!= &delta_base_cache_lru
;
2075 struct delta_base_cache_entry
*f
= (void *)lru
;
2076 if (f
->type
== OBJ_BLOB
)
2077 release_delta_base_cache(f
);
2079 for (lru
= delta_base_cache_lru
.next
;
2080 delta_base_cached
> delta_base_cache_limit
2081 && lru
!= &delta_base_cache_lru
;
2083 struct delta_base_cache_entry
*f
= (void *)lru
;
2084 release_delta_base_cache(f
);
2088 ent
->base_offset
= base_offset
;
2091 ent
->size
= base_size
;
2092 ent
->lru
.next
= &delta_base_cache_lru
;
2093 ent
->lru
.prev
= delta_base_cache_lru
.prev
;
2094 delta_base_cache_lru
.prev
->next
= &ent
->lru
;
2095 delta_base_cache_lru
.prev
= &ent
->lru
;
2098 static void *read_object(const unsigned char *sha1
, enum object_type
*type
,
2099 unsigned long *size
);
2101 static void write_pack_access_log(struct packed_git
*p
, off_t obj_offset
)
2103 static struct trace_key pack_access
= TRACE_KEY_INIT(PACK_ACCESS
);
2104 trace_printf_key(&pack_access
, "%s %"PRIuMAX
"\n",
2105 p
->pack_name
, (uintmax_t)obj_offset
);
2108 int do_check_packed_object_crc
;
2110 #define UNPACK_ENTRY_STACK_PREALLOC 64
2111 struct unpack_entry_stack_ent
{
2117 void *unpack_entry(struct packed_git
*p
, off_t obj_offset
,
2118 enum object_type
*final_type
, unsigned long *final_size
)
2120 struct pack_window
*w_curs
= NULL
;
2121 off_t curpos
= obj_offset
;
2124 enum object_type type
;
2125 struct unpack_entry_stack_ent small_delta_stack
[UNPACK_ENTRY_STACK_PREALLOC
];
2126 struct unpack_entry_stack_ent
*delta_stack
= small_delta_stack
;
2127 int delta_stack_nr
= 0, delta_stack_alloc
= UNPACK_ENTRY_STACK_PREALLOC
;
2128 int base_from_cache
= 0;
2130 write_pack_access_log(p
, obj_offset
);
2132 /* PHASE 1: drill down to the innermost base object */
2136 struct delta_base_cache_entry
*ent
;
2138 ent
= get_delta_base_cache_entry(p
, curpos
);
2139 if (eq_delta_base_cache_entry(ent
, p
, curpos
)) {
2143 clear_delta_base_cache_entry(ent
);
2144 base_from_cache
= 1;
2148 if (do_check_packed_object_crc
&& p
->index_version
> 1) {
2149 struct revindex_entry
*revidx
= find_pack_revindex(p
, obj_offset
);
2150 unsigned long len
= revidx
[1].offset
- obj_offset
;
2151 if (check_pack_crc(p
, &w_curs
, obj_offset
, len
, revidx
->nr
)) {
2152 const unsigned char *sha1
=
2153 nth_packed_object_sha1(p
, revidx
->nr
);
2154 error("bad packed object CRC for %s",
2156 mark_bad_packed_object(p
, sha1
);
2157 unuse_pack(&w_curs
);
2162 type
= unpack_object_header(p
, &w_curs
, &curpos
, &size
);
2163 if (type
!= OBJ_OFS_DELTA
&& type
!= OBJ_REF_DELTA
)
2166 base_offset
= get_delta_base(p
, &w_curs
, &curpos
, type
, obj_offset
);
2168 error("failed to validate delta base reference "
2169 "at offset %"PRIuMAX
" from %s",
2170 (uintmax_t)curpos
, p
->pack_name
);
2171 /* bail to phase 2, in hopes of recovery */
2176 /* push object, proceed to base */
2177 if (delta_stack_nr
>= delta_stack_alloc
2178 && delta_stack
== small_delta_stack
) {
2179 delta_stack_alloc
= alloc_nr(delta_stack_nr
);
2180 delta_stack
= xmalloc(sizeof(*delta_stack
)*delta_stack_alloc
);
2181 memcpy(delta_stack
, small_delta_stack
,
2182 sizeof(*delta_stack
)*delta_stack_nr
);
2184 ALLOC_GROW(delta_stack
, delta_stack_nr
+1, delta_stack_alloc
);
2186 i
= delta_stack_nr
++;
2187 delta_stack
[i
].obj_offset
= obj_offset
;
2188 delta_stack
[i
].curpos
= curpos
;
2189 delta_stack
[i
].size
= size
;
2191 curpos
= obj_offset
= base_offset
;
2194 /* PHASE 2: handle the base */
2199 die("BUG in unpack_entry: left loop at a valid delta");
2205 if (!base_from_cache
)
2206 data
= unpack_compressed_entry(p
, &w_curs
, curpos
, size
);
2210 error("unknown object type %i at offset %"PRIuMAX
" in %s",
2211 type
, (uintmax_t)obj_offset
, p
->pack_name
);
2214 /* PHASE 3: apply deltas in order */
2217 * 'data' holds the base data, or NULL if there was corruption
2219 while (delta_stack_nr
) {
2222 unsigned long delta_size
, base_size
= size
;
2228 add_delta_base_cache(p
, obj_offset
, base
, base_size
, type
);
2232 * We're probably in deep shit, but let's try to fetch
2233 * the required base anyway from another pack or loose.
2234 * This is costly but should happen only in the presence
2235 * of a corrupted pack, and is better than failing outright.
2237 struct revindex_entry
*revidx
;
2238 const unsigned char *base_sha1
;
2239 revidx
= find_pack_revindex(p
, obj_offset
);
2241 base_sha1
= nth_packed_object_sha1(p
, revidx
->nr
);
2242 error("failed to read delta base object %s"
2243 " at offset %"PRIuMAX
" from %s",
2244 sha1_to_hex(base_sha1
), (uintmax_t)obj_offset
,
2246 mark_bad_packed_object(p
, base_sha1
);
2247 base
= read_object(base_sha1
, &type
, &base_size
);
2251 i
= --delta_stack_nr
;
2252 obj_offset
= delta_stack
[i
].obj_offset
;
2253 curpos
= delta_stack
[i
].curpos
;
2254 delta_size
= delta_stack
[i
].size
;
2259 delta_data
= unpack_compressed_entry(p
, &w_curs
, curpos
, delta_size
);
2262 error("failed to unpack compressed delta "
2263 "at offset %"PRIuMAX
" from %s",
2264 (uintmax_t)curpos
, p
->pack_name
);
2269 data
= patch_delta(base
, base_size
,
2270 delta_data
, delta_size
,
2274 * We could not apply the delta; warn the user, but keep going.
2275 * Our failure will be noticed either in the next iteration of
2276 * the loop, or if this is the final delta, in the caller when
2277 * we return NULL. Those code paths will take care of making
2278 * a more explicit warning and retrying with another copy of
2282 error("failed to apply delta");
2290 unuse_pack(&w_curs
);
2292 if (delta_stack
!= small_delta_stack
)
2298 const unsigned char *nth_packed_object_sha1(struct packed_git
*p
,
2301 const unsigned char *index
= p
->index_data
;
2303 if (open_pack_index(p
))
2305 index
= p
->index_data
;
2307 if (n
>= p
->num_objects
)
2310 if (p
->index_version
== 1) {
2311 return index
+ 24 * n
+ 4;
2314 return index
+ 20 * n
;
2318 off_t
nth_packed_object_offset(const struct packed_git
*p
, uint32_t n
)
2320 const unsigned char *index
= p
->index_data
;
2322 if (p
->index_version
== 1) {
2323 return ntohl(*((uint32_t *)(index
+ 24 * n
)));
2326 index
+= 8 + p
->num_objects
* (20 + 4);
2327 off
= ntohl(*((uint32_t *)(index
+ 4 * n
)));
2328 if (!(off
& 0x80000000))
2330 index
+= p
->num_objects
* 4 + (off
& 0x7fffffff) * 8;
2331 return (((uint64_t)ntohl(*((uint32_t *)(index
+ 0)))) << 32) |
2332 ntohl(*((uint32_t *)(index
+ 4)));
2336 off_t
find_pack_entry_one(const unsigned char *sha1
,
2337 struct packed_git
*p
)
2339 const uint32_t *level1_ofs
= p
->index_data
;
2340 const unsigned char *index
= p
->index_data
;
2341 unsigned hi
, lo
, stride
;
2342 static int use_lookup
= -1;
2343 static int debug_lookup
= -1;
2345 if (debug_lookup
< 0)
2346 debug_lookup
= !!getenv("GIT_DEBUG_LOOKUP");
2349 if (open_pack_index(p
))
2351 level1_ofs
= p
->index_data
;
2352 index
= p
->index_data
;
2354 if (p
->index_version
> 1) {
2359 hi
= ntohl(level1_ofs
[*sha1
]);
2360 lo
= ((*sha1
== 0x0) ? 0 : ntohl(level1_ofs
[*sha1
- 1]));
2361 if (p
->index_version
> 1) {
2369 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32
"\n",
2370 sha1
[0], sha1
[1], sha1
[2], lo
, hi
, p
->num_objects
);
2373 use_lookup
= !!getenv("GIT_USE_LOOKUP");
2375 int pos
= sha1_entry_pos(index
, stride
, 0,
2376 lo
, hi
, p
->num_objects
, sha1
);
2379 return nth_packed_object_offset(p
, pos
);
2383 unsigned mi
= (lo
+ hi
) / 2;
2384 int cmp
= hashcmp(index
+ mi
* stride
, sha1
);
2387 printf("lo %u hi %u rg %u mi %u\n",
2388 lo
, hi
, hi
- lo
, mi
);
2390 return nth_packed_object_offset(p
, mi
);
2399 int is_pack_valid(struct packed_git
*p
)
2401 /* An already open pack is known to be valid. */
2402 if (p
->pack_fd
!= -1)
2405 /* If the pack has one window completely covering the
2406 * file size, the pack is known to be valid even if
2407 * the descriptor is not currently open.
2410 struct pack_window
*w
= p
->windows
;
2412 if (!w
->offset
&& w
->len
== p
->pack_size
)
2416 /* Force the pack to open to prove its valid. */
2417 return !open_packed_git(p
);
2420 static int fill_pack_entry(const unsigned char *sha1
,
2421 struct pack_entry
*e
,
2422 struct packed_git
*p
)
2426 if (p
->num_bad_objects
) {
2428 for (i
= 0; i
< p
->num_bad_objects
; i
++)
2429 if (!hashcmp(sha1
, p
->bad_object_sha1
+ 20 * i
))
2433 offset
= find_pack_entry_one(sha1
, p
);
2438 * We are about to tell the caller where they can locate the
2439 * requested object. We better make sure the packfile is
2440 * still here and can be accessed before supplying that
2441 * answer, as it may have been deleted since the index was
2444 if (!is_pack_valid(p
)) {
2445 warning("packfile %s cannot be accessed", p
->pack_name
);
2450 hashcpy(e
->sha1
, sha1
);
2455 * Iff a pack file contains the object named by sha1, return true and
2456 * store its location to e.
2458 static int find_pack_entry(const unsigned char *sha1
, struct pack_entry
*e
)
2460 struct packed_git
*p
;
2462 prepare_packed_git();
2466 if (last_found_pack
&& fill_pack_entry(sha1
, e
, last_found_pack
))
2469 for (p
= packed_git
; p
; p
= p
->next
) {
2470 if (p
== last_found_pack
)
2471 continue; /* we already checked this one */
2473 if (fill_pack_entry(sha1
, e
, p
)) {
2474 last_found_pack
= p
;
2481 struct packed_git
*find_sha1_pack(const unsigned char *sha1
,
2482 struct packed_git
*packs
)
2484 struct packed_git
*p
;
2486 for (p
= packs
; p
; p
= p
->next
) {
2487 if (find_pack_entry_one(sha1
, p
))
2494 static int sha1_loose_object_info(const unsigned char *sha1
,
2495 struct object_info
*oi
)
2498 unsigned long mapsize
, size
;
2503 if (oi
->delta_base_sha1
)
2504 hashclr(oi
->delta_base_sha1
);
2507 * If we don't care about type or size, then we don't
2508 * need to look inside the object at all. Note that we
2509 * do not optimize out the stat call, even if the
2510 * caller doesn't care about the disk-size, since our
2511 * return value implicitly indicates whether the
2512 * object even exists.
2514 if (!oi
->typep
&& !oi
->sizep
) {
2516 if (stat_sha1_file(sha1
, &st
) < 0)
2519 *oi
->disk_sizep
= st
.st_size
;
2523 map
= map_sha1_file(sha1
, &mapsize
);
2527 *oi
->disk_sizep
= mapsize
;
2528 if (unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
)) < 0)
2529 status
= error("unable to unpack %s header",
2531 else if ((status
= parse_sha1_header(hdr
, &size
)) < 0)
2532 status
= error("unable to parse %s header", sha1_to_hex(sha1
));
2535 git_inflate_end(&stream
);
2536 munmap(map
, mapsize
);
2538 *oi
->typep
= status
;
2542 int sha1_object_info_extended(const unsigned char *sha1
, struct object_info
*oi
, unsigned flags
)
2544 struct cached_object
*co
;
2545 struct pack_entry e
;
2547 const unsigned char *real
= lookup_replace_object_extended(sha1
, flags
);
2549 co
= find_cached_object(real
);
2552 *(oi
->typep
) = co
->type
;
2554 *(oi
->sizep
) = co
->size
;
2556 *(oi
->disk_sizep
) = 0;
2557 if (oi
->delta_base_sha1
)
2558 hashclr(oi
->delta_base_sha1
);
2559 oi
->whence
= OI_CACHED
;
2563 if (!find_pack_entry(real
, &e
)) {
2564 /* Most likely it's a loose object. */
2565 if (!sha1_loose_object_info(real
, oi
)) {
2566 oi
->whence
= OI_LOOSE
;
2570 /* Not a loose object; someone else may have just packed it. */
2571 reprepare_packed_git();
2572 if (!find_pack_entry(real
, &e
))
2576 rtype
= packed_object_info(e
.p
, e
.offset
, oi
);
2578 mark_bad_packed_object(e
.p
, real
);
2579 return sha1_object_info_extended(real
, oi
, 0);
2580 } else if (in_delta_base_cache(e
.p
, e
.offset
)) {
2581 oi
->whence
= OI_DBCACHED
;
2583 oi
->whence
= OI_PACKED
;
2584 oi
->u
.packed
.offset
= e
.offset
;
2585 oi
->u
.packed
.pack
= e
.p
;
2586 oi
->u
.packed
.is_delta
= (rtype
== OBJ_REF_DELTA
||
2587 rtype
== OBJ_OFS_DELTA
);
2593 /* returns enum object_type or negative */
2594 int sha1_object_info(const unsigned char *sha1
, unsigned long *sizep
)
2596 enum object_type type
;
2597 struct object_info oi
= {NULL
};
2601 if (sha1_object_info_extended(sha1
, &oi
, LOOKUP_REPLACE_OBJECT
) < 0)
2606 static void *read_packed_sha1(const unsigned char *sha1
,
2607 enum object_type
*type
, unsigned long *size
)
2609 struct pack_entry e
;
2612 if (!find_pack_entry(sha1
, &e
))
2614 data
= cache_or_unpack_entry(e
.p
, e
.offset
, size
, type
, 1);
2617 * We're probably in deep shit, but let's try to fetch
2618 * the required object anyway from another pack or loose.
2619 * This should happen only in the presence of a corrupted
2620 * pack, and is better than failing outright.
2622 error("failed to read object %s at offset %"PRIuMAX
" from %s",
2623 sha1_to_hex(sha1
), (uintmax_t)e
.offset
, e
.p
->pack_name
);
2624 mark_bad_packed_object(e
.p
, sha1
);
2625 data
= read_object(sha1
, type
, size
);
2630 int pretend_sha1_file(void *buf
, unsigned long len
, enum object_type type
,
2631 unsigned char *sha1
)
2633 struct cached_object
*co
;
2635 hash_sha1_file(buf
, len
, typename(type
), sha1
);
2636 if (has_sha1_file(sha1
) || find_cached_object(sha1
))
2638 ALLOC_GROW(cached_objects
, cached_object_nr
+ 1, cached_object_alloc
);
2639 co
= &cached_objects
[cached_object_nr
++];
2642 co
->buf
= xmalloc(len
);
2643 memcpy(co
->buf
, buf
, len
);
2644 hashcpy(co
->sha1
, sha1
);
2648 static void *read_object(const unsigned char *sha1
, enum object_type
*type
,
2649 unsigned long *size
)
2651 unsigned long mapsize
;
2653 struct cached_object
*co
;
2655 co
= find_cached_object(sha1
);
2659 return xmemdupz(co
->buf
, co
->size
);
2662 buf
= read_packed_sha1(sha1
, type
, size
);
2665 map
= map_sha1_file(sha1
, &mapsize
);
2667 buf
= unpack_sha1_file(map
, mapsize
, type
, size
, sha1
);
2668 munmap(map
, mapsize
);
2671 reprepare_packed_git();
2672 return read_packed_sha1(sha1
, type
, size
);
2676 * This function dies on corrupt objects; the callers who want to
2677 * deal with them should arrange to call read_object() and give error
2678 * messages themselves.
2680 void *read_sha1_file_extended(const unsigned char *sha1
,
2681 enum object_type
*type
,
2682 unsigned long *size
,
2686 const struct packed_git
*p
;
2687 const unsigned char *repl
= lookup_replace_object_extended(sha1
, flag
);
2690 data
= read_object(repl
, type
, size
);
2694 if (errno
&& errno
!= ENOENT
)
2695 die_errno("failed to read object %s", sha1_to_hex(sha1
));
2697 /* die if we replaced an object with one that does not exist */
2699 die("replacement %s not found for %s",
2700 sha1_to_hex(repl
), sha1_to_hex(sha1
));
2702 if (has_loose_object(repl
)) {
2703 const char *path
= sha1_file_name(sha1
);
2705 die("loose object %s (stored in %s) is corrupt",
2706 sha1_to_hex(repl
), path
);
2709 if ((p
= has_packed_and_bad(repl
)) != NULL
)
2710 die("packed object %s (stored in %s) is corrupt",
2711 sha1_to_hex(repl
), p
->pack_name
);
2716 void *read_object_with_reference(const unsigned char *sha1
,
2717 const char *required_type_name
,
2718 unsigned long *size
,
2719 unsigned char *actual_sha1_return
)
2721 enum object_type type
, required_type
;
2723 unsigned long isize
;
2724 unsigned char actual_sha1
[20];
2726 required_type
= type_from_string(required_type_name
);
2727 hashcpy(actual_sha1
, sha1
);
2729 int ref_length
= -1;
2730 const char *ref_type
= NULL
;
2732 buffer
= read_sha1_file(actual_sha1
, &type
, &isize
);
2735 if (type
== required_type
) {
2737 if (actual_sha1_return
)
2738 hashcpy(actual_sha1_return
, actual_sha1
);
2741 /* Handle references */
2742 else if (type
== OBJ_COMMIT
)
2744 else if (type
== OBJ_TAG
)
2745 ref_type
= "object ";
2750 ref_length
= strlen(ref_type
);
2752 if (ref_length
+ 40 > isize
||
2753 memcmp(buffer
, ref_type
, ref_length
) ||
2754 get_sha1_hex((char *) buffer
+ ref_length
, actual_sha1
)) {
2759 /* Now we have the ID of the referred-to object in
2760 * actual_sha1. Check again. */
2764 static void write_sha1_file_prepare(const void *buf
, unsigned long len
,
2765 const char *type
, unsigned char *sha1
,
2766 char *hdr
, int *hdrlen
)
2770 /* Generate the header */
2771 *hdrlen
= sprintf(hdr
, "%s %lu", type
, len
)+1;
2775 git_SHA1_Update(&c
, hdr
, *hdrlen
);
2776 git_SHA1_Update(&c
, buf
, len
);
2777 git_SHA1_Final(sha1
, &c
);
2781 * Move the just written object into its final resting place.
2782 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2783 * "moving" is only a part of what it does, when no patch between
2784 * master to pu changes the call sites of this function.
2786 int move_temp_to_file(const char *tmpfile
, const char *filename
)
2790 if (object_creation_mode
== OBJECT_CREATION_USES_RENAMES
)
2792 else if (link(tmpfile
, filename
))
2796 * Coda hack - coda doesn't like cross-directory links,
2797 * so we fall back to a rename, which will mean that it
2798 * won't be able to check collisions, but that's not a
2801 * The same holds for FAT formatted media.
2803 * When this succeeds, we just return. We have nothing
2806 if (ret
&& ret
!= EEXIST
) {
2808 if (!rename(tmpfile
, filename
))
2812 unlink_or_warn(tmpfile
);
2814 if (ret
!= EEXIST
) {
2815 return error("unable to write sha1 filename %s: %s", filename
, strerror(ret
));
2817 /* FIXME!!! Collision check here ? */
2821 if (adjust_shared_perm(filename
))
2822 return error("unable to set permission to '%s'", filename
);
2826 static int write_buffer(int fd
, const void *buf
, size_t len
)
2828 if (write_in_full(fd
, buf
, len
) < 0)
2829 return error("file write error (%s)", strerror(errno
));
2833 int hash_sha1_file(const void *buf
, unsigned long len
, const char *type
,
2834 unsigned char *sha1
)
2838 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
2842 /* Finalize a file on disk, and close it. */
2843 static void close_sha1_file(int fd
)
2845 if (fsync_object_files
)
2846 fsync_or_die(fd
, "sha1 file");
2848 die_errno("error when closing sha1 file");
2851 /* Size of directory component, including the ending '/' */
2852 static inline int directory_size(const char *filename
)
2854 const char *s
= strrchr(filename
, '/');
2857 return s
- filename
+ 1;
2861 * This creates a temporary file in the same directory as the final
2864 * We want to avoid cross-directory filename renames, because those
2865 * can have problems on various filesystems (FAT, NFS, Coda).
2867 static int create_tmpfile(char *buffer
, size_t bufsiz
, const char *filename
)
2869 int fd
, dirlen
= directory_size(filename
);
2871 if (dirlen
+ 20 > bufsiz
) {
2872 errno
= ENAMETOOLONG
;
2875 memcpy(buffer
, filename
, dirlen
);
2876 strcpy(buffer
+ dirlen
, "tmp_obj_XXXXXX");
2877 fd
= git_mkstemp_mode(buffer
, 0444);
2878 if (fd
< 0 && dirlen
&& errno
== ENOENT
) {
2879 /* Make sure the directory exists */
2880 memcpy(buffer
, filename
, dirlen
);
2881 buffer
[dirlen
-1] = 0;
2882 if (mkdir(buffer
, 0777) && errno
!= EEXIST
)
2884 if (adjust_shared_perm(buffer
))
2888 strcpy(buffer
+ dirlen
- 1, "/tmp_obj_XXXXXX");
2889 fd
= git_mkstemp_mode(buffer
, 0444);
2894 static int write_loose_object(const unsigned char *sha1
, char *hdr
, int hdrlen
,
2895 const void *buf
, unsigned long len
, time_t mtime
)
2898 unsigned char compressed
[4096];
2901 unsigned char parano_sha1
[20];
2902 static char tmp_file
[PATH_MAX
];
2903 const char *filename
= sha1_file_name(sha1
);
2905 fd
= create_tmpfile(tmp_file
, sizeof(tmp_file
), filename
);
2907 if (errno
== EACCES
)
2908 return error("insufficient permission for adding an object to repository database %s", get_object_directory());
2910 return error("unable to create temporary file: %s", strerror(errno
));
2914 memset(&stream
, 0, sizeof(stream
));
2915 git_deflate_init(&stream
, zlib_compression_level
);
2916 stream
.next_out
= compressed
;
2917 stream
.avail_out
= sizeof(compressed
);
2920 /* First header.. */
2921 stream
.next_in
= (unsigned char *)hdr
;
2922 stream
.avail_in
= hdrlen
;
2923 while (git_deflate(&stream
, 0) == Z_OK
)
2925 git_SHA1_Update(&c
, hdr
, hdrlen
);
2927 /* Then the data itself.. */
2928 stream
.next_in
= (void *)buf
;
2929 stream
.avail_in
= len
;
2931 unsigned char *in0
= stream
.next_in
;
2932 ret
= git_deflate(&stream
, Z_FINISH
);
2933 git_SHA1_Update(&c
, in0
, stream
.next_in
- in0
);
2934 if (write_buffer(fd
, compressed
, stream
.next_out
- compressed
) < 0)
2935 die("unable to write sha1 file");
2936 stream
.next_out
= compressed
;
2937 stream
.avail_out
= sizeof(compressed
);
2938 } while (ret
== Z_OK
);
2940 if (ret
!= Z_STREAM_END
)
2941 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1
), ret
);
2942 ret
= git_deflate_end_gently(&stream
);
2944 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1
), ret
);
2945 git_SHA1_Final(parano_sha1
, &c
);
2946 if (hashcmp(sha1
, parano_sha1
) != 0)
2947 die("confused by unstable object source data for %s", sha1_to_hex(sha1
));
2949 close_sha1_file(fd
);
2954 utb
.modtime
= mtime
;
2955 if (utime(tmp_file
, &utb
) < 0)
2956 warning("failed utime() on %s: %s",
2957 tmp_file
, strerror(errno
));
2960 return move_temp_to_file(tmp_file
, filename
);
2963 int write_sha1_file(const void *buf
, unsigned long len
, const char *type
, unsigned char *returnsha1
)
2965 unsigned char sha1
[20];
2969 /* Normally if we have it in the pack then we do not bother writing
2970 * it out into .git/objects/??/?{38} file.
2972 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
2974 hashcpy(returnsha1
, sha1
);
2975 if (has_sha1_file(sha1
))
2977 return write_loose_object(sha1
, hdr
, hdrlen
, buf
, len
, 0);
2980 int force_object_loose(const unsigned char *sha1
, time_t mtime
)
2984 enum object_type type
;
2989 if (has_loose_object(sha1
))
2991 buf
= read_packed_sha1(sha1
, &type
, &len
);
2993 return error("cannot read sha1_file for %s", sha1_to_hex(sha1
));
2994 hdrlen
= sprintf(hdr
, "%s %lu", typename(type
), len
) + 1;
2995 ret
= write_loose_object(sha1
, hdr
, hdrlen
, buf
, len
, mtime
);
3001 int has_pack_index(const unsigned char *sha1
)
3004 if (stat(sha1_pack_index_name(sha1
), &st
))
3009 int has_sha1_pack(const unsigned char *sha1
)
3011 struct pack_entry e
;
3012 return find_pack_entry(sha1
, &e
);
3015 int has_sha1_file(const unsigned char *sha1
)
3017 struct pack_entry e
;
3019 if (find_pack_entry(sha1
, &e
))
3021 if (has_loose_object(sha1
))
3023 reprepare_packed_git();
3024 return find_pack_entry(sha1
, &e
);
3027 static void check_tree(const void *buf
, size_t size
)
3029 struct tree_desc desc
;
3030 struct name_entry entry
;
3032 init_tree_desc(&desc
, buf
, size
);
3033 while (tree_entry(&desc
, &entry
))
3035 * tree_entry() will die() on malformed entries */
3039 static void check_commit(const void *buf
, size_t size
)
3042 memset(&c
, 0, sizeof(c
));
3043 if (parse_commit_buffer(&c
, buf
, size
))
3044 die("corrupt commit");
3047 static void check_tag(const void *buf
, size_t size
)
3050 memset(&t
, 0, sizeof(t
));
3051 if (parse_tag_buffer(&t
, buf
, size
))
3055 static int index_mem(unsigned char *sha1
, void *buf
, size_t size
,
3056 enum object_type type
,
3057 const char *path
, unsigned flags
)
3059 int ret
, re_allocated
= 0;
3060 int write_object
= flags
& HASH_WRITE_OBJECT
;
3066 * Convert blobs to git internal format
3068 if ((type
== OBJ_BLOB
) && path
) {
3069 struct strbuf nbuf
= STRBUF_INIT
;
3070 if (convert_to_git(path
, buf
, size
, &nbuf
,
3071 write_object
? safe_crlf
: SAFE_CRLF_FALSE
)) {
3072 buf
= strbuf_detach(&nbuf
, &size
);
3076 if (flags
& HASH_FORMAT_CHECK
) {
3077 if (type
== OBJ_TREE
)
3078 check_tree(buf
, size
);
3079 if (type
== OBJ_COMMIT
)
3080 check_commit(buf
, size
);
3081 if (type
== OBJ_TAG
)
3082 check_tag(buf
, size
);
3086 ret
= write_sha1_file(buf
, size
, typename(type
), sha1
);
3088 ret
= hash_sha1_file(buf
, size
, typename(type
), sha1
);
3094 static int index_stream_convert_blob(unsigned char *sha1
, int fd
,
3095 const char *path
, unsigned flags
)
3098 const int write_object
= flags
& HASH_WRITE_OBJECT
;
3099 struct strbuf sbuf
= STRBUF_INIT
;
3102 assert(would_convert_to_git_filter_fd(path
));
3104 convert_to_git_filter_fd(path
, fd
, &sbuf
,
3105 write_object
? safe_crlf
: SAFE_CRLF_FALSE
);
3108 ret
= write_sha1_file(sbuf
.buf
, sbuf
.len
, typename(OBJ_BLOB
),
3111 ret
= hash_sha1_file(sbuf
.buf
, sbuf
.len
, typename(OBJ_BLOB
),
3113 strbuf_release(&sbuf
);
3117 static int index_pipe(unsigned char *sha1
, int fd
, enum object_type type
,
3118 const char *path
, unsigned flags
)
3120 struct strbuf sbuf
= STRBUF_INIT
;
3123 if (strbuf_read(&sbuf
, fd
, 4096) >= 0)
3124 ret
= index_mem(sha1
, sbuf
.buf
, sbuf
.len
, type
, path
, flags
);
3127 strbuf_release(&sbuf
);
3131 #define SMALL_FILE_SIZE (32*1024)
3133 static int index_core(unsigned char *sha1
, int fd
, size_t size
,
3134 enum object_type type
, const char *path
,
3140 ret
= index_mem(sha1
, NULL
, size
, type
, path
, flags
);
3141 } else if (size
<= SMALL_FILE_SIZE
) {
3142 char *buf
= xmalloc(size
);
3143 if (size
== read_in_full(fd
, buf
, size
))
3144 ret
= index_mem(sha1
, buf
, size
, type
, path
, flags
);
3146 ret
= error("short read %s", strerror(errno
));
3149 void *buf
= xmmap(NULL
, size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
3150 ret
= index_mem(sha1
, buf
, size
, type
, path
, flags
);
3157 * This creates one packfile per large blob unless bulk-checkin
3158 * machinery is "plugged".
3160 * This also bypasses the usual "convert-to-git" dance, and that is on
3161 * purpose. We could write a streaming version of the converting
3162 * functions and insert that before feeding the data to fast-import
3163 * (or equivalent in-core API described above). However, that is
3164 * somewhat complicated, as we do not know the size of the filter
3165 * result, which we need to know beforehand when writing a git object.
3166 * Since the primary motivation for trying to stream from the working
3167 * tree file and to avoid mmaping it in core is to deal with large
3168 * binary blobs, they generally do not want to get any conversion, and
3169 * callers should avoid this code path when filters are requested.
3171 static int index_stream(unsigned char *sha1
, int fd
, size_t size
,
3172 enum object_type type
, const char *path
,
3175 return index_bulk_checkin(sha1
, fd
, size
, type
, path
, flags
);
3178 int index_fd(unsigned char *sha1
, int fd
, struct stat
*st
,
3179 enum object_type type
, const char *path
, unsigned flags
)
3182 size_t size
= xsize_t(st
->st_size
);
3184 if (type
== OBJ_BLOB
&& path
&& would_convert_to_git_filter_fd(path
))
3185 ret
= index_stream_convert_blob(sha1
, fd
, path
, flags
);
3186 else if (!S_ISREG(st
->st_mode
))
3187 ret
= index_pipe(sha1
, fd
, type
, path
, flags
);
3188 else if (size
<= big_file_threshold
|| type
!= OBJ_BLOB
||
3189 (path
&& would_convert_to_git(path
)))
3190 ret
= index_core(sha1
, fd
, size
, type
, path
, flags
);
3192 ret
= index_stream(sha1
, fd
, size
, type
, path
, flags
);
3197 int index_path(unsigned char *sha1
, const char *path
, struct stat
*st
, unsigned flags
)
3200 struct strbuf sb
= STRBUF_INIT
;
3202 switch (st
->st_mode
& S_IFMT
) {
3204 fd
= open(path
, O_RDONLY
);
3206 return error("open(\"%s\"): %s", path
,
3208 if (index_fd(sha1
, fd
, st
, OBJ_BLOB
, path
, flags
) < 0)
3209 return error("%s: failed to insert into database",
3213 if (strbuf_readlink(&sb
, path
, st
->st_size
)) {
3214 char *errstr
= strerror(errno
);
3215 return error("readlink(\"%s\"): %s", path
,
3218 if (!(flags
& HASH_WRITE_OBJECT
))
3219 hash_sha1_file(sb
.buf
, sb
.len
, blob_type
, sha1
);
3220 else if (write_sha1_file(sb
.buf
, sb
.len
, blob_type
, sha1
))
3221 return error("%s: failed to insert into database",
3223 strbuf_release(&sb
);
3226 return resolve_gitlink_ref(path
, "HEAD", sha1
);
3228 return error("%s: unsupported file type", path
);
3233 int read_pack_header(int fd
, struct pack_header
*header
)
3235 if (read_in_full(fd
, header
, sizeof(*header
)) < sizeof(*header
))
3236 /* "eof before pack header was fully read" */
3237 return PH_ERROR_EOF
;
3239 if (header
->hdr_signature
!= htonl(PACK_SIGNATURE
))
3240 /* "protocol error (pack signature mismatch detected)" */
3241 return PH_ERROR_PACK_SIGNATURE
;
3242 if (!pack_version_ok(header
->hdr_version
))
3243 /* "protocol error (pack version unsupported)" */
3244 return PH_ERROR_PROTOCOL
;
3248 void assert_sha1_type(const unsigned char *sha1
, enum object_type expect
)
3250 enum object_type type
= sha1_object_info(sha1
, NULL
);
3252 die("%s is not a valid object", sha1_to_hex(sha1
));
3254 die("%s is not a valid '%s' object", sha1_to_hex(sha1
),