2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
6 * This handles basic git sha1 object files - packing, unpacking,
19 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
20 #define O_NOATIME 01000000
28 static unsigned long sz_fmt(size_t s
) { return (unsigned long)s
; }
31 static size_t sz_fmt(size_t s
) { return s
; }
34 const unsigned char null_sha1
[20];
36 static unsigned int sha1_file_open_flag
= O_NOATIME
;
38 const signed char hexval_table
[256] = {
39 -1, -1, -1, -1, -1, -1, -1, -1, /* 00-07 */
40 -1, -1, -1, -1, -1, -1, -1, -1, /* 08-0f */
41 -1, -1, -1, -1, -1, -1, -1, -1, /* 10-17 */
42 -1, -1, -1, -1, -1, -1, -1, -1, /* 18-1f */
43 -1, -1, -1, -1, -1, -1, -1, -1, /* 20-27 */
44 -1, -1, -1, -1, -1, -1, -1, -1, /* 28-2f */
45 0, 1, 2, 3, 4, 5, 6, 7, /* 30-37 */
46 8, 9, -1, -1, -1, -1, -1, -1, /* 38-3f */
47 -1, 10, 11, 12, 13, 14, 15, -1, /* 40-47 */
48 -1, -1, -1, -1, -1, -1, -1, -1, /* 48-4f */
49 -1, -1, -1, -1, -1, -1, -1, -1, /* 50-57 */
50 -1, -1, -1, -1, -1, -1, -1, -1, /* 58-5f */
51 -1, 10, 11, 12, 13, 14, 15, -1, /* 60-67 */
52 -1, -1, -1, -1, -1, -1, -1, -1, /* 68-67 */
53 -1, -1, -1, -1, -1, -1, -1, -1, /* 70-77 */
54 -1, -1, -1, -1, -1, -1, -1, -1, /* 78-7f */
55 -1, -1, -1, -1, -1, -1, -1, -1, /* 80-87 */
56 -1, -1, -1, -1, -1, -1, -1, -1, /* 88-8f */
57 -1, -1, -1, -1, -1, -1, -1, -1, /* 90-97 */
58 -1, -1, -1, -1, -1, -1, -1, -1, /* 98-9f */
59 -1, -1, -1, -1, -1, -1, -1, -1, /* a0-a7 */
60 -1, -1, -1, -1, -1, -1, -1, -1, /* a8-af */
61 -1, -1, -1, -1, -1, -1, -1, -1, /* b0-b7 */
62 -1, -1, -1, -1, -1, -1, -1, -1, /* b8-bf */
63 -1, -1, -1, -1, -1, -1, -1, -1, /* c0-c7 */
64 -1, -1, -1, -1, -1, -1, -1, -1, /* c8-cf */
65 -1, -1, -1, -1, -1, -1, -1, -1, /* d0-d7 */
66 -1, -1, -1, -1, -1, -1, -1, -1, /* d8-df */
67 -1, -1, -1, -1, -1, -1, -1, -1, /* e0-e7 */
68 -1, -1, -1, -1, -1, -1, -1, -1, /* e8-ef */
69 -1, -1, -1, -1, -1, -1, -1, -1, /* f0-f7 */
70 -1, -1, -1, -1, -1, -1, -1, -1, /* f8-ff */
73 int get_sha1_hex(const char *hex
, unsigned char *sha1
)
76 for (i
= 0; i
< 20; i
++) {
77 unsigned int val
= (hexval(hex
[0]) << 4) | hexval(hex
[1]);
86 int safe_create_leading_directories(char *path
)
91 if (is_absolute_path(path
))
95 pos
= strchr(pos
, '/');
99 if (!stat(path
, &st
)) {
101 if (!S_ISDIR(st
.st_mode
)) {
106 else if (mkdir(path
, 0777)) {
110 else if (adjust_shared_perm(path
)) {
119 char * sha1_to_hex(const unsigned char *sha1
)
122 static char hexbuffer
[4][50];
123 static const char hex
[] = "0123456789abcdef";
124 char *buffer
= hexbuffer
[3 & ++bufno
], *buf
= buffer
;
127 for (i
= 0; i
< 20; i
++) {
128 unsigned int val
= *sha1
++;
129 *buf
++ = hex
[val
>> 4];
130 *buf
++ = hex
[val
& 0xf];
137 static void fill_sha1_path(char *pathbuf
, const unsigned char *sha1
)
140 for (i
= 0; i
< 20; i
++) {
141 static char hex
[] = "0123456789abcdef";
142 unsigned int val
= sha1
[i
];
143 char *pos
= pathbuf
+ i
*2 + (i
> 0);
144 *pos
++ = hex
[val
>> 4];
145 *pos
= hex
[val
& 0xf];
150 * NOTE! This returns a statically allocated buffer, so you have to be
151 * careful about using it. Do a "xstrdup()" if you need to save the
154 * Also note that this returns the location for creating. Reading
155 * SHA1 file can happen from any alternate directory listed in the
156 * DB_ENVIRONMENT environment variable if it is not found in
157 * the primary object database.
159 char *sha1_file_name(const unsigned char *sha1
)
161 static char *name
, *base
;
164 const char *sha1_file_directory
= get_object_directory();
165 int len
= strlen(sha1_file_directory
);
166 base
= xmalloc(len
+ 60);
167 memcpy(base
, sha1_file_directory
, len
);
168 memset(base
+len
, 0, 60);
171 name
= base
+ len
+ 1;
173 fill_sha1_path(name
, sha1
);
177 char *sha1_pack_name(const unsigned char *sha1
)
179 static const char hex
[] = "0123456789abcdef";
180 static char *name
, *base
, *buf
;
184 const char *sha1_file_directory
= get_object_directory();
185 int len
= strlen(sha1_file_directory
);
186 base
= xmalloc(len
+ 60);
187 sprintf(base
, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory
);
188 name
= base
+ len
+ 11;
193 for (i
= 0; i
< 20; i
++) {
194 unsigned int val
= *sha1
++;
195 *buf
++ = hex
[val
>> 4];
196 *buf
++ = hex
[val
& 0xf];
202 char *sha1_pack_index_name(const unsigned char *sha1
)
204 static const char hex
[] = "0123456789abcdef";
205 static char *name
, *base
, *buf
;
209 const char *sha1_file_directory
= get_object_directory();
210 int len
= strlen(sha1_file_directory
);
211 base
= xmalloc(len
+ 60);
212 sprintf(base
, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory
);
213 name
= base
+ len
+ 11;
218 for (i
= 0; i
< 20; i
++) {
219 unsigned int val
= *sha1
++;
220 *buf
++ = hex
[val
>> 4];
221 *buf
++ = hex
[val
& 0xf];
227 struct alternate_object_database
*alt_odb_list
;
228 static struct alternate_object_database
**alt_odb_tail
;
230 static void read_info_alternates(const char * alternates
, int depth
);
233 * Prepare alternate object database registry.
235 * The variable alt_odb_list points at the list of struct
236 * alternate_object_database. The elements on this list come from
237 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
238 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
239 * whose contents is similar to that environment variable but can be
240 * LF separated. Its base points at a statically allocated buffer that
241 * contains "/the/directory/corresponding/to/.git/objects/...", while
242 * its name points just after the slash at the end of ".git/objects/"
243 * in the example above, and has enough space to hold 40-byte hex
244 * SHA1, an extra slash for the first level indirection, and the
247 static int link_alt_odb_entry(const char * entry
, int len
, const char * relative_base
, int depth
)
250 const char *objdir
= get_object_directory();
251 struct alternate_object_database
*ent
;
252 struct alternate_object_database
*alt
;
253 /* 43 = 40-byte + 2 '/' + terminating NUL */
255 int entlen
= pfxlen
+ 43;
258 if (!is_absolute_path(entry
) && relative_base
) {
259 /* Relative alt-odb */
261 base_len
= strlen(relative_base
) + 1;
265 ent
= xmalloc(sizeof(*ent
) + entlen
);
267 if (!is_absolute_path(entry
) && relative_base
) {
268 memcpy(ent
->base
, relative_base
, base_len
- 1);
269 ent
->base
[base_len
- 1] = '/';
270 memcpy(ent
->base
+ base_len
, entry
, len
);
273 memcpy(ent
->base
, entry
, pfxlen
);
275 ent
->name
= ent
->base
+ pfxlen
+ 1;
276 ent
->base
[pfxlen
+ 3] = '/';
277 ent
->base
[pfxlen
] = ent
->base
[entlen
-1] = 0;
279 /* Detect cases where alternate disappeared */
280 if (stat(ent
->base
, &st
) || !S_ISDIR(st
.st_mode
)) {
281 error("object directory %s does not exist; "
282 "check .git/objects/info/alternates.",
288 /* Prevent the common mistake of listing the same
289 * thing twice, or object directory itself.
291 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
292 if (!memcmp(ent
->base
, alt
->base
, pfxlen
)) {
297 if (!memcmp(ent
->base
, objdir
, pfxlen
)) {
302 /* add the alternate entry */
304 alt_odb_tail
= &(ent
->next
);
307 /* recursively add alternates */
308 read_info_alternates(ent
->base
, depth
+ 1);
310 ent
->base
[pfxlen
] = '/';
315 static void link_alt_odb_entries(const char *alt
, const char *ep
, int sep
,
316 const char *relative_base
, int depth
)
318 const char *cp
, *last
;
321 error("%s: ignoring alternate object stores, nesting too deep.",
329 if (cp
< ep
&& *cp
== '#') {
330 while (cp
< ep
&& *cp
!= sep
)
335 while (cp
< ep
&& *cp
!= sep
)
338 if (!is_absolute_path(last
) && depth
) {
339 error("%s: ignoring relative alternate object store %s",
340 relative_base
, last
);
342 link_alt_odb_entry(last
, cp
- last
,
343 relative_base
, depth
);
346 while (cp
< ep
&& *cp
== sep
)
352 static void read_info_alternates(const char * relative_base
, int depth
)
357 const char alt_file_name
[] = "info/alternates";
358 /* Given that relative_base is no longer than PATH_MAX,
359 ensure that "path" has enough space to append "/", the
360 file name, "info/alternates", and a trailing NUL. */
361 char path
[PATH_MAX
+ 1 + sizeof alt_file_name
];
364 sprintf(path
, "%s/%s", relative_base
, alt_file_name
);
365 fd
= open(path
, O_RDONLY
);
368 if (fstat(fd
, &st
) || (st
.st_size
== 0)) {
372 mapsz
= xsize_t(st
.st_size
);
373 map
= xmmap(NULL
, mapsz
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
376 link_alt_odb_entries(map
, map
+ mapsz
, '\n', relative_base
, depth
);
381 void prepare_alt_odb(void)
388 alt
= getenv(ALTERNATE_DB_ENVIRONMENT
);
391 alt_odb_tail
= &alt_odb_list
;
392 link_alt_odb_entries(alt
, alt
+ strlen(alt
), ':', NULL
, 0);
394 read_info_alternates(get_object_directory(), 0);
397 static char *find_sha1_file(const unsigned char *sha1
, struct stat
*st
)
399 char *name
= sha1_file_name(sha1
);
400 struct alternate_object_database
*alt
;
405 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
407 fill_sha1_path(name
, sha1
);
408 if (!stat(alt
->base
, st
))
414 static unsigned int pack_used_ctr
;
415 static unsigned int pack_mmap_calls
;
416 static unsigned int peak_pack_open_windows
;
417 static unsigned int pack_open_windows
;
418 static size_t peak_pack_mapped
;
419 static size_t pack_mapped
;
420 struct packed_git
*packed_git
;
422 void pack_report(void)
425 "pack_report: getpagesize() = %10" SZ_FMT
"\n"
426 "pack_report: core.packedGitWindowSize = %10" SZ_FMT
"\n"
427 "pack_report: core.packedGitLimit = %10" SZ_FMT
"\n",
428 sz_fmt(getpagesize()),
429 sz_fmt(packed_git_window_size
),
430 sz_fmt(packed_git_limit
));
432 "pack_report: pack_used_ctr = %10u\n"
433 "pack_report: pack_mmap_calls = %10u\n"
434 "pack_report: pack_open_windows = %10u / %10u\n"
435 "pack_report: pack_mapped = "
436 "%10" SZ_FMT
" / %10" SZ_FMT
"\n",
439 pack_open_windows
, peak_pack_open_windows
,
440 sz_fmt(pack_mapped
), sz_fmt(peak_pack_mapped
));
443 static int check_packed_git_idx(const char *path
, struct packed_git
*p
)
446 struct pack_idx_header
*hdr
;
448 uint32_t version
, nr
, i
, *index
;
449 int fd
= open(path
, O_RDONLY
);
454 if (fstat(fd
, &st
)) {
458 idx_size
= xsize_t(st
.st_size
);
459 if (idx_size
< 4 * 256 + 20 + 20) {
461 return error("index file %s is too small", path
);
463 idx_map
= xmmap(NULL
, idx_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
467 if (hdr
->idx_signature
== htonl(PACK_IDX_SIGNATURE
)) {
468 version
= ntohl(hdr
->idx_version
);
469 if (version
< 2 || version
> 2) {
470 munmap(idx_map
, idx_size
);
471 return error("index file %s is version %d"
472 " and is not supported by this binary"
473 " (try upgrading GIT to a newer version)",
482 index
+= 2; /* skip index header */
483 for (i
= 0; i
< 256; i
++) {
484 uint32_t n
= ntohl(index
[i
]);
486 munmap(idx_map
, idx_size
);
487 return error("non-monotonic index %s", path
);
495 * - 256 index entries 4 bytes each
496 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
497 * - 20-byte SHA1 of the packfile
498 * - 20-byte SHA1 file checksum
500 if (idx_size
!= 4*256 + nr
* 24 + 20 + 20) {
501 munmap(idx_map
, idx_size
);
502 return error("wrong index v1 file size in %s", path
);
504 } else if (version
== 2) {
507 * - 8 bytes of header
508 * - 256 index entries 4 bytes each
509 * - 20-byte sha1 entry * nr
510 * - 4-byte crc entry * nr
511 * - 4-byte offset entry * nr
512 * - 20-byte SHA1 of the packfile
513 * - 20-byte SHA1 file checksum
514 * And after the 4-byte offset table might be a
515 * variable sized table containing 8-byte entries
516 * for offsets larger than 2^31.
518 unsigned long min_size
= 8 + 4*256 + nr
*(20 + 4 + 4) + 20 + 20;
519 unsigned long max_size
= min_size
;
521 max_size
+= (nr
- 1)*8;
522 if (idx_size
< min_size
|| idx_size
> max_size
) {
523 munmap(idx_map
, idx_size
);
524 return error("wrong index v2 file size in %s", path
);
526 if (idx_size
!= min_size
&&
528 * make sure we can deal with large pack offsets.
529 * 31-bit signed offset won't be enough, neither
530 * 32-bit unsigned one will be.
532 (sizeof(off_t
) <= 4)) {
533 munmap(idx_map
, idx_size
);
534 return error("pack too large for current definition of off_t in %s", path
);
538 p
->index_version
= version
;
539 p
->index_data
= idx_map
;
540 p
->index_size
= idx_size
;
545 int open_pack_index(struct packed_git
*p
)
553 idx_name
= xstrdup(p
->pack_name
);
554 strcpy(idx_name
+ strlen(idx_name
) - strlen(".pack"), ".idx");
555 ret
= check_packed_git_idx(idx_name
, p
);
560 static void scan_windows(struct packed_git
*p
,
561 struct packed_git
**lru_p
,
562 struct pack_window
**lru_w
,
563 struct pack_window
**lru_l
)
565 struct pack_window
*w
, *w_l
;
567 for (w_l
= NULL
, w
= p
->windows
; w
; w
= w
->next
) {
569 if (!*lru_w
|| w
->last_used
< (*lru_w
)->last_used
) {
579 static int unuse_one_window(struct packed_git
*current
, int keep_fd
)
581 struct packed_git
*p
, *lru_p
= NULL
;
582 struct pack_window
*lru_w
= NULL
, *lru_l
= NULL
;
585 scan_windows(current
, &lru_p
, &lru_w
, &lru_l
);
586 for (p
= packed_git
; p
; p
= p
->next
)
587 scan_windows(p
, &lru_p
, &lru_w
, &lru_l
);
589 munmap(lru_w
->base
, lru_w
->len
);
590 pack_mapped
-= lru_w
->len
;
592 lru_l
->next
= lru_w
->next
;
594 lru_p
->windows
= lru_w
->next
;
595 if (!lru_p
->windows
&& lru_p
->pack_fd
!= keep_fd
) {
596 close(lru_p
->pack_fd
);
607 void release_pack_memory(size_t need
, int fd
)
609 size_t cur
= pack_mapped
;
610 while (need
>= (cur
- pack_mapped
) && unuse_one_window(NULL
, fd
))
614 void unuse_pack(struct pack_window
**w_cursor
)
616 struct pack_window
*w
= *w_cursor
;
624 * Do not call this directly as this leaks p->pack_fd on error return;
625 * call open_packed_git() instead.
627 static int open_packed_git_1(struct packed_git
*p
)
630 struct pack_header hdr
;
631 unsigned char sha1
[20];
632 unsigned char *idx_sha1
;
635 if (!p
->index_data
&& open_pack_index(p
))
636 return error("packfile %s index unavailable", p
->pack_name
);
638 p
->pack_fd
= open(p
->pack_name
, O_RDONLY
);
639 if (p
->pack_fd
< 0 || fstat(p
->pack_fd
, &st
))
642 /* If we created the struct before we had the pack we lack size. */
644 if (!S_ISREG(st
.st_mode
))
645 return error("packfile %s not a regular file", p
->pack_name
);
646 p
->pack_size
= st
.st_size
;
647 } else if (p
->pack_size
!= st
.st_size
)
648 return error("packfile %s size changed", p
->pack_name
);
650 /* We leave these file descriptors open with sliding mmap;
651 * there is no point keeping them open across exec(), though.
653 fd_flag
= fcntl(p
->pack_fd
, F_GETFD
, 0);
655 return error("cannot determine file descriptor flags");
656 fd_flag
|= FD_CLOEXEC
;
657 if (fcntl(p
->pack_fd
, F_SETFD
, fd_flag
) == -1)
658 return error("cannot set FD_CLOEXEC");
660 /* Verify we recognize this pack file format. */
661 if (read_in_full(p
->pack_fd
, &hdr
, sizeof(hdr
)) != sizeof(hdr
))
662 return error("file %s is far too short to be a packfile", p
->pack_name
);
663 if (hdr
.hdr_signature
!= htonl(PACK_SIGNATURE
))
664 return error("file %s is not a GIT packfile", p
->pack_name
);
665 if (!pack_version_ok(hdr
.hdr_version
))
666 return error("packfile %s is version %u and not supported"
667 " (try upgrading GIT to a newer version)",
668 p
->pack_name
, ntohl(hdr
.hdr_version
));
670 /* Verify the pack matches its index. */
671 if (p
->num_objects
!= ntohl(hdr
.hdr_entries
))
672 return error("packfile %s claims to have %u objects"
673 " while index indicates %u objects",
674 p
->pack_name
, ntohl(hdr
.hdr_entries
),
676 if (lseek(p
->pack_fd
, p
->pack_size
- sizeof(sha1
), SEEK_SET
) == -1)
677 return error("end of packfile %s is unavailable", p
->pack_name
);
678 if (read_in_full(p
->pack_fd
, sha1
, sizeof(sha1
)) != sizeof(sha1
))
679 return error("packfile %s signature is unavailable", p
->pack_name
);
680 idx_sha1
= ((unsigned char *)p
->index_data
) + p
->index_size
- 40;
681 if (hashcmp(sha1
, idx_sha1
))
682 return error("packfile %s does not match index", p
->pack_name
);
686 static int open_packed_git(struct packed_git
*p
)
688 if (!open_packed_git_1(p
))
690 if (p
->pack_fd
!= -1) {
697 static int in_window(struct pack_window
*win
, off_t offset
)
699 /* We must promise at least 20 bytes (one hash) after the
700 * offset is available from this window, otherwise the offset
701 * is not actually in this window and a different window (which
702 * has that one hash excess) must be used. This is to support
703 * the object header and delta base parsing routines below.
705 off_t win_off
= win
->offset
;
706 return win_off
<= offset
707 && (offset
+ 20) <= (win_off
+ win
->len
);
710 unsigned char* use_pack(struct packed_git
*p
,
711 struct pack_window
**w_cursor
,
715 struct pack_window
*win
= *w_cursor
;
717 if (p
->pack_fd
== -1 && open_packed_git(p
))
718 die("packfile %s cannot be accessed", p
->pack_name
);
720 /* Since packfiles end in a hash of their content and its
721 * pointless to ask for an offset into the middle of that
722 * hash, and the in_window function above wouldn't match
723 * don't allow an offset too close to the end of the file.
725 if (offset
> (p
->pack_size
- 20))
726 die("offset beyond end of packfile (truncated pack?)");
728 if (!win
|| !in_window(win
, offset
)) {
731 for (win
= p
->windows
; win
; win
= win
->next
) {
732 if (in_window(win
, offset
))
736 size_t window_align
= packed_git_window_size
/ 2;
738 win
= xcalloc(1, sizeof(*win
));
739 win
->offset
= (offset
/ window_align
) * window_align
;
740 len
= p
->pack_size
- win
->offset
;
741 if (len
> packed_git_window_size
)
742 len
= packed_git_window_size
;
743 win
->len
= (size_t)len
;
744 pack_mapped
+= win
->len
;
745 while (packed_git_limit
< pack_mapped
746 && unuse_one_window(p
, p
->pack_fd
))
748 win
->base
= xmmap(NULL
, win
->len
,
749 PROT_READ
, MAP_PRIVATE
,
750 p
->pack_fd
, win
->offset
);
751 if (win
->base
== MAP_FAILED
)
752 die("packfile %s cannot be mapped: %s",
757 if (pack_mapped
> peak_pack_mapped
)
758 peak_pack_mapped
= pack_mapped
;
759 if (pack_open_windows
> peak_pack_open_windows
)
760 peak_pack_open_windows
= pack_open_windows
;
761 win
->next
= p
->windows
;
765 if (win
!= *w_cursor
) {
766 win
->last_used
= pack_used_ctr
++;
770 offset
-= win
->offset
;
772 *left
= win
->len
- xsize_t(offset
);
773 return win
->base
+ offset
;
776 struct packed_git
*add_packed_git(const char *path
, int path_len
, int local
)
779 struct packed_git
*p
= xmalloc(sizeof(*p
) + path_len
+ 2);
782 * Make sure a corresponding .pack file exists and that
783 * the index looks sane.
785 path_len
-= strlen(".idx");
788 memcpy(p
->pack_name
, path
, path_len
);
789 strcpy(p
->pack_name
+ path_len
, ".pack");
790 if (stat(p
->pack_name
, &st
) || !S_ISREG(st
.st_mode
)) {
795 /* ok, it looks sane as far as we can check without
796 * actually mapping the pack file.
798 p
->index_version
= 0;
799 p
->index_data
= NULL
;
802 p
->pack_size
= st
.st_size
;
806 p
->pack_local
= local
;
807 p
->mtime
= st
.st_mtime
;
808 if (path_len
< 40 || get_sha1_hex(path
+ path_len
- 40, p
->sha1
))
813 struct packed_git
*parse_pack_index(unsigned char *sha1
)
815 char *path
= sha1_pack_index_name(sha1
);
816 return parse_pack_index_file(sha1
, path
);
819 struct packed_git
*parse_pack_index_file(const unsigned char *sha1
,
820 const char *idx_path
)
822 const char *path
= sha1_pack_name(sha1
);
823 struct packed_git
*p
= xmalloc(sizeof(*p
) + strlen(path
) + 2);
825 if (check_packed_git_idx(idx_path
, p
)) {
830 strcpy(p
->pack_name
, path
);
835 hashcpy(p
->sha1
, sha1
);
839 void install_packed_git(struct packed_git
*pack
)
841 pack
->next
= packed_git
;
845 static void prepare_packed_git_one(char *objdir
, int local
)
847 /* Ensure that this buffer is large enough so that we can
848 append "/pack/" without clobbering the stack even if
849 strlen(objdir) were PATH_MAX. */
850 char path
[PATH_MAX
+ 1 + 4 + 1 + 1];
855 sprintf(path
, "%s/pack", objdir
);
860 error("unable to open object pack directory: %s: %s",
861 path
, strerror(errno
));
865 while ((de
= readdir(dir
)) != NULL
) {
866 int namelen
= strlen(de
->d_name
);
867 struct packed_git
*p
;
869 if (!has_extension(de
->d_name
, ".idx"))
872 if (len
+ namelen
+ 1 > sizeof(path
))
875 /* Don't reopen a pack we already have. */
876 strcpy(path
+ len
, de
->d_name
);
877 for (p
= packed_git
; p
; p
= p
->next
) {
878 if (!memcmp(path
, p
->pack_name
, len
+ namelen
- 4))
883 /* See if it really is a valid .idx file with corresponding
884 * .pack file that we can map.
886 p
= add_packed_git(path
, len
+ namelen
, local
);
889 install_packed_git(p
);
894 static int sort_pack(const void *a_
, const void *b_
)
896 struct packed_git
*a
= *((struct packed_git
**)a_
);
897 struct packed_git
*b
= *((struct packed_git
**)b_
);
901 * Local packs tend to contain objects specific to our
902 * variant of the project than remote ones. In addition,
903 * remote ones could be on a network mounted filesystem.
904 * Favor local ones for these reasons.
906 st
= a
->pack_local
- b
->pack_local
;
911 * Younger packs tend to contain more recent objects,
912 * and more recent objects tend to get accessed more
915 if (a
->mtime
< b
->mtime
)
917 else if (a
->mtime
== b
->mtime
)
922 static void rearrange_packed_git(void)
924 struct packed_git
**ary
, *p
;
927 for (n
= 0, p
= packed_git
; p
; p
= p
->next
)
932 /* prepare an array of packed_git for easier sorting */
933 ary
= xcalloc(n
, sizeof(struct packed_git
*));
934 for (n
= 0, p
= packed_git
; p
; p
= p
->next
)
937 qsort(ary
, n
, sizeof(struct packed_git
*), sort_pack
);
939 /* link them back again */
940 for (i
= 0; i
< n
- 1; i
++)
941 ary
[i
]->next
= ary
[i
+ 1];
942 ary
[n
- 1]->next
= NULL
;
948 static int prepare_packed_git_run_once
= 0;
949 void prepare_packed_git(void)
951 struct alternate_object_database
*alt
;
953 if (prepare_packed_git_run_once
)
955 prepare_packed_git_one(get_object_directory(), 1);
957 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
959 prepare_packed_git_one(alt
->base
, 0);
962 rearrange_packed_git();
963 prepare_packed_git_run_once
= 1;
966 void reprepare_packed_git(void)
968 prepare_packed_git_run_once
= 0;
969 prepare_packed_git();
972 int check_sha1_signature(const unsigned char *sha1
, void *map
, unsigned long size
, const char *type
)
974 unsigned char real_sha1
[20];
975 hash_sha1_file(map
, size
, type
, real_sha1
);
976 return hashcmp(sha1
, real_sha1
) ? -1 : 0;
979 static void *map_sha1_file(const unsigned char *sha1
, unsigned long *size
)
984 char *filename
= find_sha1_file(sha1
, &st
);
990 fd
= open(filename
, O_RDONLY
| sha1_file_open_flag
);
992 /* See if it works without O_NOATIME */
993 switch (sha1_file_open_flag
) {
995 fd
= open(filename
, O_RDONLY
);
1003 /* If it failed once, it will probably fail again.
1004 * Stop using O_NOATIME
1006 sha1_file_open_flag
= 0;
1008 *size
= xsize_t(st
.st_size
);
1009 map
= xmmap(NULL
, *size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
1014 static int legacy_loose_object(unsigned char *map
)
1019 * Is it a zlib-compressed buffer? If so, the first byte
1020 * must be 0x78 (15-bit window size, deflated), and the
1021 * first 16-bit word is evenly divisible by 31
1023 word
= (map
[0] << 8) + map
[1];
1024 if (map
[0] == 0x78 && !(word
% 31))
1030 unsigned long unpack_object_header_gently(const unsigned char *buf
, unsigned long len
, enum object_type
*type
, unsigned long *sizep
)
1035 unsigned long used
= 0;
1038 *type
= (c
>> 4) & 7;
1044 if (sizeof(long) * 8 <= shift
)
1047 size
+= (c
& 0x7f) << shift
;
1054 static int unpack_sha1_header(z_stream
*stream
, unsigned char *map
, unsigned long mapsize
, void *buffer
, unsigned long bufsiz
)
1056 unsigned long size
, used
;
1057 static const char valid_loose_object_type
[8] = {
1059 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
1060 0, /* "delta" and others are invalid in a loose object */
1062 enum object_type type
;
1064 /* Get the data stream */
1065 memset(stream
, 0, sizeof(*stream
));
1066 stream
->next_in
= map
;
1067 stream
->avail_in
= mapsize
;
1068 stream
->next_out
= buffer
;
1069 stream
->avail_out
= bufsiz
;
1071 if (legacy_loose_object(map
)) {
1072 inflateInit(stream
);
1073 return inflate(stream
, 0);
1078 * There used to be a second loose object header format which
1079 * was meant to mimic the in-pack format, allowing for direct
1080 * copy of the object data. This format turned up not to be
1081 * really worth it and we don't write it any longer. But we
1082 * can still read it.
1084 used
= unpack_object_header_gently(map
, mapsize
, &type
, &size
);
1085 if (!used
|| !valid_loose_object_type
[type
])
1090 /* Set up the stream for the rest.. */
1091 stream
->next_in
= map
;
1092 stream
->avail_in
= mapsize
;
1093 inflateInit(stream
);
1095 /* And generate the fake traditional header */
1096 stream
->total_out
= 1 + snprintf(buffer
, bufsiz
, "%s %lu",
1097 typename(type
), size
);
1101 static void *unpack_sha1_rest(z_stream
*stream
, void *buffer
, unsigned long size
, const unsigned char *sha1
)
1103 int bytes
= strlen(buffer
) + 1;
1104 unsigned char *buf
= xmalloc(1+size
);
1108 n
= stream
->total_out
- bytes
;
1111 memcpy(buf
, (char *) buffer
+ bytes
, n
);
1113 if (bytes
<= size
) {
1115 * The above condition must be (bytes <= size), not
1116 * (bytes < size). In other words, even though we
1117 * expect no more output and set avail_out to zer0,
1118 * the input zlib stream may have bytes that express
1119 * "this concludes the stream", and we *do* want to
1122 * Otherwise we would not be able to test that we
1123 * consumed all the input to reach the expected size;
1124 * we also want to check that zlib tells us that all
1125 * went well with status == Z_STREAM_END at the end.
1127 stream
->next_out
= buf
+ bytes
;
1128 stream
->avail_out
= size
- bytes
;
1129 while (status
== Z_OK
)
1130 status
= inflate(stream
, Z_FINISH
);
1133 if (status
== Z_STREAM_END
&& !stream
->avail_in
) {
1139 error("corrupt loose object '%s'", sha1_to_hex(sha1
));
1140 else if (stream
->avail_in
)
1141 error("garbage at end of loose object '%s'",
1148 * We used to just use "sscanf()", but that's actually way
1149 * too permissive for what we want to check. So do an anal
1150 * object header parse by hand.
1152 static int parse_sha1_header(const char *hdr
, unsigned long *sizep
)
1159 * The type can be at most ten bytes (including the
1160 * terminating '\0' that we add), and is followed by
1169 if (i
>= sizeof(type
))
1175 * The length must follow immediately, and be in canonical
1176 * decimal format (ie "010" is not valid).
1178 size
= *hdr
++ - '0';
1183 unsigned long c
= *hdr
- '0';
1187 size
= size
* 10 + c
;
1193 * The length must be followed by a zero byte
1195 return *hdr
? -1 : type_from_string(type
);
1198 static void *unpack_sha1_file(void *map
, unsigned long mapsize
, enum object_type
*type
, unsigned long *size
, const unsigned char *sha1
)
1204 ret
= unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
));
1205 if (ret
< Z_OK
|| (*type
= parse_sha1_header(hdr
, size
)) < 0)
1208 return unpack_sha1_rest(&stream
, hdr
, *size
, sha1
);
1211 unsigned long get_size_from_delta(struct packed_git
*p
,
1212 struct pack_window
**w_curs
,
1215 const unsigned char *data
;
1216 unsigned char delta_head
[20], *in
;
1220 memset(&stream
, 0, sizeof(stream
));
1221 stream
.next_out
= delta_head
;
1222 stream
.avail_out
= sizeof(delta_head
);
1224 inflateInit(&stream
);
1226 in
= use_pack(p
, w_curs
, curpos
, &stream
.avail_in
);
1227 stream
.next_in
= in
;
1228 st
= inflate(&stream
, Z_FINISH
);
1229 curpos
+= stream
.next_in
- in
;
1230 } while ((st
== Z_OK
|| st
== Z_BUF_ERROR
) &&
1231 stream
.total_out
< sizeof(delta_head
));
1232 inflateEnd(&stream
);
1233 if ((st
!= Z_STREAM_END
) && stream
.total_out
!= sizeof(delta_head
))
1234 die("delta data unpack-initial failed");
1236 /* Examine the initial part of the delta to figure out
1241 /* ignore base size */
1242 get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
1244 /* Read the result size */
1245 return get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
1248 static off_t
get_delta_base(struct packed_git
*p
,
1249 struct pack_window
**w_curs
,
1251 enum object_type type
,
1252 off_t delta_obj_offset
)
1254 unsigned char *base_info
= use_pack(p
, w_curs
, *curpos
, NULL
);
1257 /* use_pack() assured us we have [base_info, base_info + 20)
1258 * as a range that we can look at without walking off the
1259 * end of the mapped window. Its actually the hash size
1260 * that is assured. An OFS_DELTA longer than the hash size
1261 * is stupid, as then a REF_DELTA would be smaller to store.
1263 if (type
== OBJ_OFS_DELTA
) {
1265 unsigned char c
= base_info
[used
++];
1266 base_offset
= c
& 127;
1269 if (!base_offset
|| MSB(base_offset
, 7))
1270 die("offset value overflow for delta base object");
1271 c
= base_info
[used
++];
1272 base_offset
= (base_offset
<< 7) + (c
& 127);
1274 base_offset
= delta_obj_offset
- base_offset
;
1275 if (base_offset
>= delta_obj_offset
)
1276 die("delta base offset out of bound");
1278 } else if (type
== OBJ_REF_DELTA
) {
1279 /* The base entry _must_ be in the same pack */
1280 base_offset
= find_pack_entry_one(base_info
, p
);
1282 die("failed to find delta-pack base object %s",
1283 sha1_to_hex(base_info
));
1286 die("I am totally screwed");
1290 /* forward declaration for a mutually recursive function */
1291 static int packed_object_info(struct packed_git
*p
, off_t offset
,
1292 unsigned long *sizep
);
1294 static int packed_delta_info(struct packed_git
*p
,
1295 struct pack_window
**w_curs
,
1297 enum object_type type
,
1299 unsigned long *sizep
)
1303 base_offset
= get_delta_base(p
, w_curs
, &curpos
, type
, obj_offset
);
1304 type
= packed_object_info(p
, base_offset
, NULL
);
1306 /* We choose to only get the type of the base object and
1307 * ignore potentially corrupt pack file that expects the delta
1308 * based on a base with a wrong size. This saves tons of
1312 *sizep
= get_size_from_delta(p
, w_curs
, curpos
);
1317 static int unpack_object_header(struct packed_git
*p
,
1318 struct pack_window
**w_curs
,
1320 unsigned long *sizep
)
1322 unsigned char *base
;
1325 enum object_type type
;
1327 /* use_pack() assures us we have [base, base + 20) available
1328 * as a range that we can look at at. (Its actually the hash
1329 * size that is assured.) With our object header encoding
1330 * the maximum deflated object size is 2^137, which is just
1331 * insane, so we know won't exceed what we have been given.
1333 base
= use_pack(p
, w_curs
, *curpos
, &left
);
1334 used
= unpack_object_header_gently(base
, left
, &type
, sizep
);
1336 die("object offset outside of pack file");
1342 const char *packed_object_info_detail(struct packed_git
*p
,
1344 unsigned long *size
,
1345 unsigned long *store_size
,
1346 unsigned int *delta_chain_length
,
1347 unsigned char *base_sha1
)
1349 struct pack_window
*w_curs
= NULL
;
1351 unsigned long dummy
;
1352 unsigned char *next_sha1
;
1353 enum object_type type
;
1355 *delta_chain_length
= 0;
1356 curpos
= obj_offset
;
1357 type
= unpack_object_header(p
, &w_curs
, &curpos
, size
);
1362 die("pack %s contains unknown object type %d",
1363 p
->pack_name
, type
);
1368 *store_size
= 0; /* notyet */
1369 unuse_pack(&w_curs
);
1370 return typename(type
);
1372 obj_offset
= get_delta_base(p
, &w_curs
, &curpos
, type
, obj_offset
);
1373 if (*delta_chain_length
== 0) {
1374 /* TODO: find base_sha1 as pointed by curpos */
1379 next_sha1
= use_pack(p
, &w_curs
, curpos
, NULL
);
1380 if (*delta_chain_length
== 0)
1381 hashcpy(base_sha1
, next_sha1
);
1382 obj_offset
= find_pack_entry_one(next_sha1
, p
);
1385 (*delta_chain_length
)++;
1386 curpos
= obj_offset
;
1387 type
= unpack_object_header(p
, &w_curs
, &curpos
, &dummy
);
1391 static int packed_object_info(struct packed_git
*p
, off_t obj_offset
,
1392 unsigned long *sizep
)
1394 struct pack_window
*w_curs
= NULL
;
1396 off_t curpos
= obj_offset
;
1397 enum object_type type
;
1399 type
= unpack_object_header(p
, &w_curs
, &curpos
, &size
);
1404 type
= packed_delta_info(p
, &w_curs
, curpos
,
1405 type
, obj_offset
, sizep
);
1415 die("pack %s contains unknown object type %d",
1416 p
->pack_name
, type
);
1418 unuse_pack(&w_curs
);
1422 static void *unpack_compressed_entry(struct packed_git
*p
,
1423 struct pack_window
**w_curs
,
1429 unsigned char *buffer
, *in
;
1431 buffer
= xmalloc(size
+ 1);
1433 memset(&stream
, 0, sizeof(stream
));
1434 stream
.next_out
= buffer
;
1435 stream
.avail_out
= size
;
1437 inflateInit(&stream
);
1439 in
= use_pack(p
, w_curs
, curpos
, &stream
.avail_in
);
1440 stream
.next_in
= in
;
1441 st
= inflate(&stream
, Z_FINISH
);
1442 curpos
+= stream
.next_in
- in
;
1443 } while (st
== Z_OK
|| st
== Z_BUF_ERROR
);
1444 inflateEnd(&stream
);
1445 if ((st
!= Z_STREAM_END
) || stream
.total_out
!= size
) {
1453 #define MAX_DELTA_CACHE (256)
1455 static size_t delta_base_cached
;
1457 static struct delta_base_cache_lru_list
{
1458 struct delta_base_cache_lru_list
*prev
;
1459 struct delta_base_cache_lru_list
*next
;
1460 } delta_base_cache_lru
= { &delta_base_cache_lru
, &delta_base_cache_lru
};
1462 static struct delta_base_cache_entry
{
1463 struct delta_base_cache_lru_list lru
;
1465 struct packed_git
*p
;
1468 enum object_type type
;
1469 } delta_base_cache
[MAX_DELTA_CACHE
];
1471 static unsigned long pack_entry_hash(struct packed_git
*p
, off_t base_offset
)
1475 hash
= (unsigned long)p
+ (unsigned long)base_offset
;
1476 hash
+= (hash
>> 8) + (hash
>> 16);
1477 return hash
% MAX_DELTA_CACHE
;
1480 static void *cache_or_unpack_entry(struct packed_git
*p
, off_t base_offset
,
1481 unsigned long *base_size
, enum object_type
*type
, int keep_cache
)
1484 unsigned long hash
= pack_entry_hash(p
, base_offset
);
1485 struct delta_base_cache_entry
*ent
= delta_base_cache
+ hash
;
1488 if (ret
&& ent
->p
== p
&& ent
->base_offset
== base_offset
)
1489 goto found_cache_entry
;
1490 return unpack_entry(p
, base_offset
, type
, base_size
);
1495 ent
->lru
.next
->prev
= ent
->lru
.prev
;
1496 ent
->lru
.prev
->next
= ent
->lru
.next
;
1497 delta_base_cached
-= ent
->size
;
1499 ret
= xmemdupz(ent
->data
, ent
->size
);
1502 *base_size
= ent
->size
;
1506 static inline void release_delta_base_cache(struct delta_base_cache_entry
*ent
)
1511 ent
->lru
.next
->prev
= ent
->lru
.prev
;
1512 ent
->lru
.prev
->next
= ent
->lru
.next
;
1513 delta_base_cached
-= ent
->size
;
1517 static void add_delta_base_cache(struct packed_git
*p
, off_t base_offset
,
1518 void *base
, unsigned long base_size
, enum object_type type
)
1520 unsigned long hash
= pack_entry_hash(p
, base_offset
);
1521 struct delta_base_cache_entry
*ent
= delta_base_cache
+ hash
;
1522 struct delta_base_cache_lru_list
*lru
;
1524 release_delta_base_cache(ent
);
1525 delta_base_cached
+= base_size
;
1527 for (lru
= delta_base_cache_lru
.next
;
1528 delta_base_cached
> delta_base_cache_limit
1529 && lru
!= &delta_base_cache_lru
;
1531 struct delta_base_cache_entry
*f
= (void *)lru
;
1532 if (f
->type
== OBJ_BLOB
)
1533 release_delta_base_cache(f
);
1535 for (lru
= delta_base_cache_lru
.next
;
1536 delta_base_cached
> delta_base_cache_limit
1537 && lru
!= &delta_base_cache_lru
;
1539 struct delta_base_cache_entry
*f
= (void *)lru
;
1540 release_delta_base_cache(f
);
1544 ent
->base_offset
= base_offset
;
1547 ent
->size
= base_size
;
1548 ent
->lru
.next
= &delta_base_cache_lru
;
1549 ent
->lru
.prev
= delta_base_cache_lru
.prev
;
1550 delta_base_cache_lru
.prev
->next
= &ent
->lru
;
1551 delta_base_cache_lru
.prev
= &ent
->lru
;
1554 static void *unpack_delta_entry(struct packed_git
*p
,
1555 struct pack_window
**w_curs
,
1557 unsigned long delta_size
,
1559 enum object_type
*type
,
1560 unsigned long *sizep
)
1562 void *delta_data
, *result
, *base
;
1563 unsigned long base_size
;
1566 base_offset
= get_delta_base(p
, w_curs
, &curpos
, *type
, obj_offset
);
1567 base
= cache_or_unpack_entry(p
, base_offset
, &base_size
, type
, 0);
1569 die("failed to read delta base object"
1570 " at %"PRIuMAX
" from %s",
1571 (uintmax_t)base_offset
, p
->pack_name
);
1573 delta_data
= unpack_compressed_entry(p
, w_curs
, curpos
, delta_size
);
1575 die("failed to unpack compressed delta"
1576 " at %"PRIuMAX
" from %s",
1577 (uintmax_t)curpos
, p
->pack_name
);
1578 result
= patch_delta(base
, base_size
,
1579 delta_data
, delta_size
,
1582 die("failed to apply delta");
1584 add_delta_base_cache(p
, base_offset
, base
, base_size
, *type
);
1588 void *unpack_entry(struct packed_git
*p
, off_t obj_offset
,
1589 enum object_type
*type
, unsigned long *sizep
)
1591 struct pack_window
*w_curs
= NULL
;
1592 off_t curpos
= obj_offset
;
1595 *type
= unpack_object_header(p
, &w_curs
, &curpos
, sizep
);
1599 data
= unpack_delta_entry(p
, &w_curs
, curpos
, *sizep
,
1600 obj_offset
, type
, sizep
);
1606 data
= unpack_compressed_entry(p
, &w_curs
, curpos
, *sizep
);
1609 die("unknown object type %i in %s", *type
, p
->pack_name
);
1611 unuse_pack(&w_curs
);
1615 const unsigned char *nth_packed_object_sha1(struct packed_git
*p
,
1618 const unsigned char *index
= p
->index_data
;
1620 if (open_pack_index(p
))
1622 index
= p
->index_data
;
1624 if (n
>= p
->num_objects
)
1627 if (p
->index_version
== 1) {
1628 return index
+ 24 * n
+ 4;
1631 return index
+ 20 * n
;
1635 static off_t
nth_packed_object_offset(const struct packed_git
*p
, uint32_t n
)
1637 const unsigned char *index
= p
->index_data
;
1639 if (p
->index_version
== 1) {
1640 return ntohl(*((uint32_t *)(index
+ 24 * n
)));
1643 index
+= 8 + p
->num_objects
* (20 + 4);
1644 off
= ntohl(*((uint32_t *)(index
+ 4 * n
)));
1645 if (!(off
& 0x80000000))
1647 index
+= p
->num_objects
* 4 + (off
& 0x7fffffff) * 8;
1648 return (((uint64_t)ntohl(*((uint32_t *)(index
+ 0)))) << 32) |
1649 ntohl(*((uint32_t *)(index
+ 4)));
1653 off_t
find_pack_entry_one(const unsigned char *sha1
,
1654 struct packed_git
*p
)
1656 const uint32_t *level1_ofs
= p
->index_data
;
1657 const unsigned char *index
= p
->index_data
;
1661 if (open_pack_index(p
))
1663 level1_ofs
= p
->index_data
;
1664 index
= p
->index_data
;
1666 if (p
->index_version
> 1) {
1671 hi
= ntohl(level1_ofs
[*sha1
]);
1672 lo
= ((*sha1
== 0x0) ? 0 : ntohl(level1_ofs
[*sha1
- 1]));
1675 unsigned mi
= (lo
+ hi
) / 2;
1676 unsigned x
= (p
->index_version
> 1) ? (mi
* 20) : (mi
* 24 + 4);
1677 int cmp
= hashcmp(index
+ x
, sha1
);
1679 return nth_packed_object_offset(p
, mi
);
1688 int matches_pack_name(struct packed_git
*p
, const char *name
)
1690 const char *last_c
, *c
;
1692 if (!strcmp(p
->pack_name
, name
))
1695 for (c
= p
->pack_name
, last_c
= c
; *c
;)
1700 if (!strcmp(last_c
, name
))
1706 static int find_pack_entry(const unsigned char *sha1
, struct pack_entry
*e
, const char **ignore_packed
)
1708 static struct packed_git
*last_found
= (void *)1;
1709 struct packed_git
*p
;
1712 prepare_packed_git();
1715 p
= (last_found
== (void *)1) ? packed_git
: last_found
;
1718 if (ignore_packed
) {
1720 for (ig
= ignore_packed
; *ig
; ig
++)
1721 if (matches_pack_name(p
, *ig
))
1727 offset
= find_pack_entry_one(sha1
, p
);
1730 * We are about to tell the caller where they can
1731 * locate the requested object. We better make
1732 * sure the packfile is still here and can be
1733 * accessed before supplying that answer, as
1734 * it may have been deleted since the index
1737 if (p
->pack_fd
== -1 && open_packed_git(p
)) {
1738 error("packfile %s cannot be accessed", p
->pack_name
);
1743 hashcpy(e
->sha1
, sha1
);
1749 if (p
== last_found
)
1753 if (p
== last_found
)
1759 struct packed_git
*find_sha1_pack(const unsigned char *sha1
,
1760 struct packed_git
*packs
)
1762 struct packed_git
*p
;
1764 for (p
= packs
; p
; p
= p
->next
) {
1765 if (find_pack_entry_one(sha1
, p
))
1772 static int sha1_loose_object_info(const unsigned char *sha1
, unsigned long *sizep
)
1775 unsigned long mapsize
, size
;
1780 map
= map_sha1_file(sha1
, &mapsize
);
1782 return error("unable to find %s", sha1_to_hex(sha1
));
1783 if (unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
)) < 0)
1784 status
= error("unable to unpack %s header",
1786 else if ((status
= parse_sha1_header(hdr
, &size
)) < 0)
1787 status
= error("unable to parse %s header", sha1_to_hex(sha1
));
1790 inflateEnd(&stream
);
1791 munmap(map
, mapsize
);
1795 int sha1_object_info(const unsigned char *sha1
, unsigned long *sizep
)
1797 struct pack_entry e
;
1799 if (!find_pack_entry(sha1
, &e
, NULL
)) {
1800 reprepare_packed_git();
1801 if (!find_pack_entry(sha1
, &e
, NULL
))
1802 return sha1_loose_object_info(sha1
, sizep
);
1804 return packed_object_info(e
.p
, e
.offset
, sizep
);
1807 static void *read_packed_sha1(const unsigned char *sha1
,
1808 enum object_type
*type
, unsigned long *size
)
1810 struct pack_entry e
;
1812 if (!find_pack_entry(sha1
, &e
, NULL
))
1815 return cache_or_unpack_entry(e
.p
, e
.offset
, size
, type
, 1);
1819 * This is meant to hold a *small* number of objects that you would
1820 * want read_sha1_file() to be able to return, but yet you do not want
1821 * to write them into the object store (e.g. a browse-only
1824 static struct cached_object
{
1825 unsigned char sha1
[20];
1826 enum object_type type
;
1830 static int cached_object_nr
, cached_object_alloc
;
1832 static struct cached_object
*find_cached_object(const unsigned char *sha1
)
1835 struct cached_object
*co
= cached_objects
;
1837 for (i
= 0; i
< cached_object_nr
; i
++, co
++) {
1838 if (!hashcmp(co
->sha1
, sha1
))
1844 int pretend_sha1_file(void *buf
, unsigned long len
, enum object_type type
,
1845 unsigned char *sha1
)
1847 struct cached_object
*co
;
1849 hash_sha1_file(buf
, len
, typename(type
), sha1
);
1850 if (has_sha1_file(sha1
) || find_cached_object(sha1
))
1852 if (cached_object_alloc
<= cached_object_nr
) {
1853 cached_object_alloc
= alloc_nr(cached_object_alloc
);
1854 cached_objects
= xrealloc(cached_objects
,
1855 sizeof(*cached_objects
) *
1856 cached_object_alloc
);
1858 co
= &cached_objects
[cached_object_nr
++];
1861 co
->buf
= xmalloc(len
);
1862 memcpy(co
->buf
, buf
, len
);
1863 hashcpy(co
->sha1
, sha1
);
1867 void *read_sha1_file(const unsigned char *sha1
, enum object_type
*type
,
1868 unsigned long *size
)
1870 unsigned long mapsize
;
1872 struct cached_object
*co
;
1874 co
= find_cached_object(sha1
);
1878 return xmemdupz(co
->buf
, co
->size
);
1881 buf
= read_packed_sha1(sha1
, type
, size
);
1884 map
= map_sha1_file(sha1
, &mapsize
);
1886 buf
= unpack_sha1_file(map
, mapsize
, type
, size
, sha1
);
1887 munmap(map
, mapsize
);
1890 reprepare_packed_git();
1891 return read_packed_sha1(sha1
, type
, size
);
1894 void *read_object_with_reference(const unsigned char *sha1
,
1895 const char *required_type_name
,
1896 unsigned long *size
,
1897 unsigned char *actual_sha1_return
)
1899 enum object_type type
, required_type
;
1901 unsigned long isize
;
1902 unsigned char actual_sha1
[20];
1904 required_type
= type_from_string(required_type_name
);
1905 hashcpy(actual_sha1
, sha1
);
1907 int ref_length
= -1;
1908 const char *ref_type
= NULL
;
1910 buffer
= read_sha1_file(actual_sha1
, &type
, &isize
);
1913 if (type
== required_type
) {
1915 if (actual_sha1_return
)
1916 hashcpy(actual_sha1_return
, actual_sha1
);
1919 /* Handle references */
1920 else if (type
== OBJ_COMMIT
)
1922 else if (type
== OBJ_TAG
)
1923 ref_type
= "object ";
1928 ref_length
= strlen(ref_type
);
1930 if (memcmp(buffer
, ref_type
, ref_length
) ||
1931 get_sha1_hex((char *) buffer
+ ref_length
, actual_sha1
)) {
1936 /* Now we have the ID of the referred-to object in
1937 * actual_sha1. Check again. */
1941 static void write_sha1_file_prepare(const void *buf
, unsigned long len
,
1942 const char *type
, unsigned char *sha1
,
1943 char *hdr
, int *hdrlen
)
1947 /* Generate the header */
1948 *hdrlen
= sprintf(hdr
, "%s %lu", type
, len
)+1;
1952 SHA1_Update(&c
, hdr
, *hdrlen
);
1953 SHA1_Update(&c
, buf
, len
);
1954 SHA1_Final(sha1
, &c
);
1958 * Link the tempfile to the final place, possibly creating the
1959 * last directory level as you do so.
1961 * Returns the errno on failure, 0 on success.
1963 static int link_temp_to_file(const char *tmpfile
, const char *filename
)
1968 if (!link(tmpfile
, filename
))
1972 * Try to mkdir the last path component if that failed.
1974 * Re-try the "link()" regardless of whether the mkdir
1975 * succeeds, since a race might mean that somebody
1979 dir
= strrchr(filename
, '/');
1982 if (!mkdir(filename
, 0777) && adjust_shared_perm(filename
)) {
1987 if (!link(tmpfile
, filename
))
1995 * Move the just written object into its final resting place
1997 int move_temp_to_file(const char *tmpfile
, const char *filename
)
1999 int ret
= link_temp_to_file(tmpfile
, filename
);
2002 * Coda hack - coda doesn't like cross-directory links,
2003 * so we fall back to a rename, which will mean that it
2004 * won't be able to check collisions, but that's not a
2007 * The same holds for FAT formatted media.
2009 * When this succeeds, we just return 0. We have nothing
2012 if (ret
&& ret
!= EEXIST
) {
2013 if (!rename(tmpfile
, filename
))
2019 if (ret
!= EEXIST
) {
2020 return error("unable to write sha1 filename %s: %s\n", filename
, strerror(ret
));
2022 /* FIXME!!! Collision check here ? */
2028 static int write_buffer(int fd
, const void *buf
, size_t len
)
2030 if (write_in_full(fd
, buf
, len
) < 0)
2031 return error("file write error (%s)", strerror(errno
));
2035 int hash_sha1_file(const void *buf
, unsigned long len
, const char *type
,
2036 unsigned char *sha1
)
2040 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
2044 int write_sha1_file(void *buf
, unsigned long len
, const char *type
, unsigned char *returnsha1
)
2047 unsigned char *compressed
;
2049 unsigned char sha1
[20];
2051 static char tmpfile
[PATH_MAX
];
2055 /* Normally if we have it in the pack then we do not bother writing
2056 * it out into .git/objects/??/?{38} file.
2058 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
2059 filename
= sha1_file_name(sha1
);
2061 hashcpy(returnsha1
, sha1
);
2062 if (has_sha1_file(sha1
))
2064 fd
= open(filename
, O_RDONLY
);
2067 * FIXME!!! We might do collision checking here, but we'd
2068 * need to uncompress the old file and check it. Later.
2074 if (errno
!= ENOENT
) {
2075 return error("sha1 file %s: %s\n", filename
, strerror(errno
));
2078 snprintf(tmpfile
, sizeof(tmpfile
), "%s/tmp_obj_XXXXXX", get_object_directory());
2080 fd
= mkstemp(tmpfile
);
2083 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
2085 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile
, strerror(errno
));
2089 memset(&stream
, 0, sizeof(stream
));
2090 deflateInit(&stream
, zlib_compression_level
);
2091 size
= 8 + deflateBound(&stream
, len
+hdrlen
);
2092 compressed
= xmalloc(size
);
2095 stream
.next_out
= compressed
;
2096 stream
.avail_out
= size
;
2098 /* First header.. */
2099 stream
.next_in
= (unsigned char *)hdr
;
2100 stream
.avail_in
= hdrlen
;
2101 while (deflate(&stream
, 0) == Z_OK
)
2104 /* Then the data itself.. */
2105 stream
.next_in
= buf
;
2106 stream
.avail_in
= len
;
2107 ret
= deflate(&stream
, Z_FINISH
);
2108 if (ret
!= Z_STREAM_END
)
2109 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1
), ret
);
2111 ret
= deflateEnd(&stream
);
2113 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1
), ret
);
2115 size
= stream
.total_out
;
2117 if (write_buffer(fd
, compressed
, size
) < 0)
2118 die("unable to write sha1 file");
2121 die("unable to write sha1 file");
2124 return move_temp_to_file(tmpfile
, filename
);
2128 * We need to unpack and recompress the object for writing
2129 * it out to a different file.
2131 static void *repack_object(const unsigned char *sha1
, unsigned long *objsize
)
2135 unsigned char *unpacked
;
2137 enum object_type type
;
2142 /* need to unpack and recompress it by itself */
2143 unpacked
= read_packed_sha1(sha1
, &type
, &len
);
2145 error("cannot read sha1_file for %s", sha1_to_hex(sha1
));
2147 hdrlen
= sprintf(hdr
, "%s %lu", typename(type
), len
) + 1;
2150 memset(&stream
, 0, sizeof(stream
));
2151 deflateInit(&stream
, zlib_compression_level
);
2152 size
= deflateBound(&stream
, len
+ hdrlen
);
2153 buf
= xmalloc(size
);
2156 stream
.next_out
= buf
;
2157 stream
.avail_out
= size
;
2159 /* First header.. */
2160 stream
.next_in
= (void *)hdr
;
2161 stream
.avail_in
= hdrlen
;
2162 while (deflate(&stream
, 0) == Z_OK
)
2165 /* Then the data itself.. */
2166 stream
.next_in
= unpacked
;
2167 stream
.avail_in
= len
;
2168 while (deflate(&stream
, Z_FINISH
) == Z_OK
)
2170 deflateEnd(&stream
);
2173 *objsize
= stream
.total_out
;
2177 int write_sha1_to_fd(int fd
, const unsigned char *sha1
)
2180 unsigned long objsize
;
2181 void *buf
= map_sha1_file(sha1
, &objsize
);
2184 retval
= write_buffer(fd
, buf
, objsize
);
2185 munmap(buf
, objsize
);
2189 buf
= repack_object(sha1
, &objsize
);
2190 retval
= write_buffer(fd
, buf
, objsize
);
2195 int write_sha1_from_fd(const unsigned char *sha1
, int fd
, char *buffer
,
2196 size_t bufsize
, size_t *bufposn
)
2198 char tmpfile
[PATH_MAX
];
2201 unsigned char real_sha1
[20];
2202 unsigned char discard
[4096];
2206 snprintf(tmpfile
, sizeof(tmpfile
), "%s/tmp_obj_XXXXXX", get_object_directory());
2208 local
= mkstemp(tmpfile
);
2211 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
2213 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile
, strerror(errno
));
2216 memset(&stream
, 0, sizeof(stream
));
2218 inflateInit(&stream
);
2225 stream
.avail_in
= *bufposn
;
2226 stream
.next_in
= (unsigned char *) buffer
;
2228 stream
.next_out
= discard
;
2229 stream
.avail_out
= sizeof(discard
);
2230 ret
= inflate(&stream
, Z_SYNC_FLUSH
);
2231 SHA1_Update(&c
, discard
, sizeof(discard
) -
2233 } while (stream
.avail_in
&& ret
== Z_OK
);
2234 if (write_buffer(local
, buffer
, *bufposn
- stream
.avail_in
) < 0)
2235 die("unable to write sha1 file");
2236 memmove(buffer
, buffer
+ *bufposn
- stream
.avail_in
,
2238 *bufposn
= stream
.avail_in
;
2242 size
= xread(fd
, buffer
+ *bufposn
, bufsize
- *bufposn
);
2247 return error("Connection closed?");
2248 perror("Reading from connection");
2253 inflateEnd(&stream
);
2255 fchmod(local
, 0444);
2256 if (close(local
) != 0)
2257 die("unable to write sha1 file");
2258 SHA1_Final(real_sha1
, &c
);
2259 if (ret
!= Z_STREAM_END
) {
2261 return error("File %s corrupted", sha1_to_hex(sha1
));
2263 if (hashcmp(sha1
, real_sha1
)) {
2265 return error("File %s has bad hash", sha1_to_hex(sha1
));
2268 return move_temp_to_file(tmpfile
, sha1_file_name(sha1
));
2271 int has_pack_index(const unsigned char *sha1
)
2274 if (stat(sha1_pack_index_name(sha1
), &st
))
2279 int has_pack_file(const unsigned char *sha1
)
2282 if (stat(sha1_pack_name(sha1
), &st
))
2287 int has_sha1_pack(const unsigned char *sha1
, const char **ignore_packed
)
2289 struct pack_entry e
;
2290 return find_pack_entry(sha1
, &e
, ignore_packed
);
2293 int has_sha1_file(const unsigned char *sha1
)
2296 struct pack_entry e
;
2298 if (find_pack_entry(sha1
, &e
, NULL
))
2300 return find_sha1_file(sha1
, &st
) ? 1 : 0;
2303 int index_pipe(unsigned char *sha1
, int fd
, const char *type
, int write_object
)
2308 strbuf_init(&buf
, 0);
2309 if (strbuf_read(&buf
, fd
, 4096) < 0) {
2310 strbuf_release(&buf
);
2317 ret
= write_sha1_file(buf
.buf
, buf
.len
, type
, sha1
);
2319 ret
= hash_sha1_file(buf
.buf
, buf
.len
, type
, sha1
);
2320 strbuf_release(&buf
);
2325 int index_fd(unsigned char *sha1
, int fd
, struct stat
*st
, int write_object
,
2326 enum object_type type
, const char *path
)
2328 size_t size
= xsize_t(st
->st_size
);
2330 int ret
, re_allocated
= 0;
2333 buf
= xmmap(NULL
, size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
2340 * Convert blobs to git internal format
2342 if ((type
== OBJ_BLOB
) && S_ISREG(st
->st_mode
)) {
2344 strbuf_init(&nbuf
, 0);
2345 if (convert_to_git(path
, buf
, size
, &nbuf
)) {
2347 buf
= strbuf_detach(&nbuf
, &size
);
2353 ret
= write_sha1_file(buf
, size
, typename(type
), sha1
);
2355 ret
= hash_sha1_file(buf
, size
, typename(type
), sha1
);
2365 int index_path(unsigned char *sha1
, const char *path
, struct stat
*st
, int write_object
)
2371 switch (st
->st_mode
& S_IFMT
) {
2373 fd
= open(path
, O_RDONLY
);
2375 return error("open(\"%s\"): %s", path
,
2377 if (index_fd(sha1
, fd
, st
, write_object
, OBJ_BLOB
, path
) < 0)
2378 return error("%s: failed to insert into database",
2382 len
= xsize_t(st
->st_size
);
2383 target
= xmalloc(len
+ 1);
2384 if (readlink(path
, target
, len
+ 1) != st
->st_size
) {
2385 char *errstr
= strerror(errno
);
2387 return error("readlink(\"%s\"): %s", path
,
2391 hash_sha1_file(target
, len
, blob_type
, sha1
);
2392 else if (write_sha1_file(target
, len
, blob_type
, sha1
))
2393 return error("%s: failed to insert into database",
2398 return resolve_gitlink_ref(path
, "HEAD", sha1
);
2400 return error("%s: unsupported file type", path
);
2405 int read_pack_header(int fd
, struct pack_header
*header
)
2407 char *c
= (char*)header
;
2408 ssize_t remaining
= sizeof(struct pack_header
);
2410 ssize_t r
= xread(fd
, c
, remaining
);
2412 /* "eof before pack header was fully read" */
2413 return PH_ERROR_EOF
;
2416 } while (remaining
> 0);
2417 if (header
->hdr_signature
!= htonl(PACK_SIGNATURE
))
2418 /* "protocol error (pack signature mismatch detected)" */
2419 return PH_ERROR_PACK_SIGNATURE
;
2420 if (!pack_version_ok(header
->hdr_version
))
2421 /* "protocol error (pack version unsupported)" */
2422 return PH_ERROR_PROTOCOL
;