2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
6 * This handles basic git sha1 object files - packing, unpacking,
18 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
19 #define O_NOATIME 01000000
25 const unsigned char null_sha1
[20];
27 static unsigned int sha1_file_open_flag
= O_NOATIME
;
29 signed char hexval_table
[256] = {
30 -1, -1, -1, -1, -1, -1, -1, -1, /* 00-07 */
31 -1, -1, -1, -1, -1, -1, -1, -1, /* 08-0f */
32 -1, -1, -1, -1, -1, -1, -1, -1, /* 10-17 */
33 -1, -1, -1, -1, -1, -1, -1, -1, /* 18-1f */
34 -1, -1, -1, -1, -1, -1, -1, -1, /* 20-27 */
35 -1, -1, -1, -1, -1, -1, -1, -1, /* 28-2f */
36 0, 1, 2, 3, 4, 5, 6, 7, /* 30-37 */
37 8, 9, -1, -1, -1, -1, -1, -1, /* 38-3f */
38 -1, 10, 11, 12, 13, 14, 15, -1, /* 40-47 */
39 -1, -1, -1, -1, -1, -1, -1, -1, /* 48-4f */
40 -1, -1, -1, -1, -1, -1, -1, -1, /* 50-57 */
41 -1, -1, -1, -1, -1, -1, -1, -1, /* 58-5f */
42 -1, 10, 11, 12, 13, 14, 15, -1, /* 60-67 */
43 -1, -1, -1, -1, -1, -1, -1, -1, /* 68-67 */
44 -1, -1, -1, -1, -1, -1, -1, -1, /* 70-77 */
45 -1, -1, -1, -1, -1, -1, -1, -1, /* 78-7f */
46 -1, -1, -1, -1, -1, -1, -1, -1, /* 80-87 */
47 -1, -1, -1, -1, -1, -1, -1, -1, /* 88-8f */
48 -1, -1, -1, -1, -1, -1, -1, -1, /* 90-97 */
49 -1, -1, -1, -1, -1, -1, -1, -1, /* 98-9f */
50 -1, -1, -1, -1, -1, -1, -1, -1, /* a0-a7 */
51 -1, -1, -1, -1, -1, -1, -1, -1, /* a8-af */
52 -1, -1, -1, -1, -1, -1, -1, -1, /* b0-b7 */
53 -1, -1, -1, -1, -1, -1, -1, -1, /* b8-bf */
54 -1, -1, -1, -1, -1, -1, -1, -1, /* c0-c7 */
55 -1, -1, -1, -1, -1, -1, -1, -1, /* c8-cf */
56 -1, -1, -1, -1, -1, -1, -1, -1, /* d0-d7 */
57 -1, -1, -1, -1, -1, -1, -1, -1, /* d8-df */
58 -1, -1, -1, -1, -1, -1, -1, -1, /* e0-e7 */
59 -1, -1, -1, -1, -1, -1, -1, -1, /* e8-ef */
60 -1, -1, -1, -1, -1, -1, -1, -1, /* f0-f7 */
61 -1, -1, -1, -1, -1, -1, -1, -1, /* f8-ff */
64 int get_sha1_hex(const char *hex
, unsigned char *sha1
)
67 for (i
= 0; i
< 20; i
++) {
68 unsigned int val
= (hexval(hex
[0]) << 4) | hexval(hex
[1]);
77 int safe_create_leading_directories(char *path
)
86 pos
= strchr(pos
, '/');
90 if (!stat(path
, &st
)) {
92 if (!S_ISDIR(st
.st_mode
)) {
97 else if (mkdir(path
, 0777)) {
101 else if (adjust_shared_perm(path
)) {
110 char * sha1_to_hex(const unsigned char *sha1
)
113 static char hexbuffer
[4][50];
114 static const char hex
[] = "0123456789abcdef";
115 char *buffer
= hexbuffer
[3 & ++bufno
], *buf
= buffer
;
118 for (i
= 0; i
< 20; i
++) {
119 unsigned int val
= *sha1
++;
120 *buf
++ = hex
[val
>> 4];
121 *buf
++ = hex
[val
& 0xf];
128 static void fill_sha1_path(char *pathbuf
, const unsigned char *sha1
)
131 for (i
= 0; i
< 20; i
++) {
132 static char hex
[] = "0123456789abcdef";
133 unsigned int val
= sha1
[i
];
134 char *pos
= pathbuf
+ i
*2 + (i
> 0);
135 *pos
++ = hex
[val
>> 4];
136 *pos
= hex
[val
& 0xf];
141 * NOTE! This returns a statically allocated buffer, so you have to be
142 * careful about using it. Do a "xstrdup()" if you need to save the
145 * Also note that this returns the location for creating. Reading
146 * SHA1 file can happen from any alternate directory listed in the
147 * DB_ENVIRONMENT environment variable if it is not found in
148 * the primary object database.
150 char *sha1_file_name(const unsigned char *sha1
)
152 static char *name
, *base
;
155 const char *sha1_file_directory
= get_object_directory();
156 int len
= strlen(sha1_file_directory
);
157 base
= xmalloc(len
+ 60);
158 memcpy(base
, sha1_file_directory
, len
);
159 memset(base
+len
, 0, 60);
162 name
= base
+ len
+ 1;
164 fill_sha1_path(name
, sha1
);
168 char *sha1_pack_name(const unsigned char *sha1
)
170 static const char hex
[] = "0123456789abcdef";
171 static char *name
, *base
, *buf
;
175 const char *sha1_file_directory
= get_object_directory();
176 int len
= strlen(sha1_file_directory
);
177 base
= xmalloc(len
+ 60);
178 sprintf(base
, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory
);
179 name
= base
+ len
+ 11;
184 for (i
= 0; i
< 20; i
++) {
185 unsigned int val
= *sha1
++;
186 *buf
++ = hex
[val
>> 4];
187 *buf
++ = hex
[val
& 0xf];
193 char *sha1_pack_index_name(const unsigned char *sha1
)
195 static const char hex
[] = "0123456789abcdef";
196 static char *name
, *base
, *buf
;
200 const char *sha1_file_directory
= get_object_directory();
201 int len
= strlen(sha1_file_directory
);
202 base
= xmalloc(len
+ 60);
203 sprintf(base
, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory
);
204 name
= base
+ len
+ 11;
209 for (i
= 0; i
< 20; i
++) {
210 unsigned int val
= *sha1
++;
211 *buf
++ = hex
[val
>> 4];
212 *buf
++ = hex
[val
& 0xf];
218 struct alternate_object_database
*alt_odb_list
;
219 static struct alternate_object_database
**alt_odb_tail
;
221 static void read_info_alternates(const char * alternates
, int depth
);
224 * Prepare alternate object database registry.
226 * The variable alt_odb_list points at the list of struct
227 * alternate_object_database. The elements on this list come from
228 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
229 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
230 * whose contents is similar to that environment variable but can be
231 * LF separated. Its base points at a statically allocated buffer that
232 * contains "/the/directory/corresponding/to/.git/objects/...", while
233 * its name points just after the slash at the end of ".git/objects/"
234 * in the example above, and has enough space to hold 40-byte hex
235 * SHA1, an extra slash for the first level indirection, and the
238 static int link_alt_odb_entry(const char * entry
, int len
, const char * relative_base
, int depth
)
241 const char *objdir
= get_object_directory();
242 struct alternate_object_database
*ent
;
243 struct alternate_object_database
*alt
;
244 /* 43 = 40-byte + 2 '/' + terminating NUL */
246 int entlen
= pfxlen
+ 43;
249 if (*entry
!= '/' && relative_base
) {
250 /* Relative alt-odb */
252 base_len
= strlen(relative_base
) + 1;
256 ent
= xmalloc(sizeof(*ent
) + entlen
);
258 if (*entry
!= '/' && relative_base
) {
259 memcpy(ent
->base
, relative_base
, base_len
- 1);
260 ent
->base
[base_len
- 1] = '/';
261 memcpy(ent
->base
+ base_len
, entry
, len
);
264 memcpy(ent
->base
, entry
, pfxlen
);
266 ent
->name
= ent
->base
+ pfxlen
+ 1;
267 ent
->base
[pfxlen
+ 3] = '/';
268 ent
->base
[pfxlen
] = ent
->base
[entlen
-1] = 0;
270 /* Detect cases where alternate disappeared */
271 if (stat(ent
->base
, &st
) || !S_ISDIR(st
.st_mode
)) {
272 error("object directory %s does not exist; "
273 "check .git/objects/info/alternates.",
279 /* Prevent the common mistake of listing the same
280 * thing twice, or object directory itself.
282 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
283 if (!memcmp(ent
->base
, alt
->base
, pfxlen
)) {
288 if (!memcmp(ent
->base
, objdir
, pfxlen
)) {
293 /* add the alternate entry */
295 alt_odb_tail
= &(ent
->next
);
298 /* recursively add alternates */
299 read_info_alternates(ent
->base
, depth
+ 1);
301 ent
->base
[pfxlen
] = '/';
306 static void link_alt_odb_entries(const char *alt
, const char *ep
, int sep
,
307 const char *relative_base
, int depth
)
309 const char *cp
, *last
;
312 error("%s: ignoring alternate object stores, nesting too deep.",
320 if (cp
< ep
&& *cp
== '#') {
321 while (cp
< ep
&& *cp
!= sep
)
326 while (cp
< ep
&& *cp
!= sep
)
329 if ((*last
!= '/') && depth
) {
330 error("%s: ignoring relative alternate object store %s",
331 relative_base
, last
);
333 link_alt_odb_entry(last
, cp
- last
,
334 relative_base
, depth
);
337 while (cp
< ep
&& *cp
== sep
)
343 static void read_info_alternates(const char * relative_base
, int depth
)
350 sprintf(path
, "%s/info/alternates", relative_base
);
351 fd
= open(path
, O_RDONLY
);
354 if (fstat(fd
, &st
) || (st
.st_size
== 0)) {
358 map
= mmap(NULL
, st
.st_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
360 if (map
== MAP_FAILED
)
363 link_alt_odb_entries(map
, map
+ st
.st_size
, '\n', relative_base
, depth
);
365 munmap(map
, st
.st_size
);
368 void prepare_alt_odb(void)
372 alt
= getenv(ALTERNATE_DB_ENVIRONMENT
);
377 alt_odb_tail
= &alt_odb_list
;
378 link_alt_odb_entries(alt
, alt
+ strlen(alt
), ':', NULL
, 0);
380 read_info_alternates(get_object_directory(), 0);
383 static char *find_sha1_file(const unsigned char *sha1
, struct stat
*st
)
385 char *name
= sha1_file_name(sha1
);
386 struct alternate_object_database
*alt
;
391 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
393 fill_sha1_path(name
, sha1
);
394 if (!stat(alt
->base
, st
))
400 static int pack_used_ctr
;
401 static unsigned long pack_mapped
;
402 struct packed_git
*packed_git
;
404 static int check_packed_git_idx(const char *path
, unsigned long *idx_size_
,
409 unsigned long idx_size
;
411 int fd
= open(path
, O_RDONLY
);
415 if (fstat(fd
, &st
)) {
419 idx_size
= st
.st_size
;
420 idx_map
= mmap(NULL
, idx_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
422 if (idx_map
== MAP_FAILED
)
427 *idx_size_
= idx_size
;
429 /* check index map */
430 if (idx_size
< 4*256 + 20 + 20)
431 return error("index file too small");
433 for (i
= 0; i
< 256; i
++) {
434 unsigned int n
= ntohl(index
[i
]);
436 return error("non-monotonic index");
442 * - 256 index entries 4 bytes each
443 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
444 * - 20-byte SHA1 of the packfile
445 * - 20-byte SHA1 file checksum
447 if (idx_size
!= 4*256 + nr
* 24 + 20 + 20)
448 return error("wrong index file size");
453 static int unuse_one_packed_git(void)
455 struct packed_git
*p
, *lru
= NULL
;
457 for (p
= packed_git
; p
; p
= p
->next
) {
458 if (!p
->windows
|| p
->windows
->inuse_cnt
)
460 if (!lru
|| p
->windows
->last_used
< lru
->windows
->last_used
)
465 munmap(lru
->windows
->base
, lru
->windows
->len
);
471 void unuse_packed_git(struct packed_git
*p
)
474 p
->windows
->inuse_cnt
--;
477 int use_packed_git(struct packed_git
*p
)
481 /* We created the struct before we had the pack */
482 stat(p
->pack_name
, &st
);
483 if (!S_ISREG(st
.st_mode
))
484 die("packfile %s not a regular file", p
->pack_name
);
485 p
->pack_size
= st
.st_size
;
490 struct pack_window
*win
;
491 struct pack_header
*hdr
;
493 pack_mapped
+= p
->pack_size
;
494 while (packed_git_limit
< pack_mapped
&& unuse_one_packed_git())
496 fd
= open(p
->pack_name
, O_RDONLY
);
498 die("packfile %s cannot be opened", p
->pack_name
);
499 if (fstat(fd
, &st
)) {
501 die("packfile %s cannot be opened", p
->pack_name
);
503 if (st
.st_size
!= p
->pack_size
)
504 die("packfile %s size mismatch.", p
->pack_name
);
505 win
= xcalloc(1, sizeof(*win
));
506 win
->len
= p
->pack_size
;
507 win
->base
= mmap(NULL
, p
->pack_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
509 if (win
->base
== MAP_FAILED
)
510 die("packfile %s cannot be mapped.", p
->pack_name
);
513 /* Check if we understand this pack file. If we don't we're
514 * likely too old to handle it.
516 hdr
= (struct pack_header
*)win
->base
;
517 if (hdr
->hdr_signature
!= htonl(PACK_SIGNATURE
))
518 die("packfile %s isn't actually a pack.", p
->pack_name
);
519 if (!pack_version_ok(hdr
->hdr_version
))
520 die("packfile %s is version %i and not supported"
521 " (try upgrading GIT to a newer version)",
522 p
->pack_name
, ntohl(hdr
->hdr_version
));
524 /* Check if the pack file matches with the index file.
527 if (hashcmp((unsigned char *)(p
->index_base
) +
530 p
->pack_size
- 20)) {
531 die("packfile %s does not match index.", p
->pack_name
);
534 p
->windows
->last_used
= pack_used_ctr
++;
535 p
->windows
->inuse_cnt
++;
539 struct packed_git
*add_packed_git(char *path
, int path_len
, int local
)
542 struct packed_git
*p
;
543 unsigned long idx_size
;
545 unsigned char sha1
[20];
547 if (check_packed_git_idx(path
, &idx_size
, &idx_map
))
550 /* do we have a corresponding .pack file? */
551 strcpy(path
+ path_len
- 4, ".pack");
552 if (stat(path
, &st
) || !S_ISREG(st
.st_mode
)) {
553 munmap(idx_map
, idx_size
);
556 /* ok, it looks sane as far as we can check without
557 * actually mapping the pack file.
559 p
= xmalloc(sizeof(*p
) + path_len
+ 2);
560 strcpy(p
->pack_name
, path
);
561 p
->index_size
= idx_size
;
562 p
->pack_size
= st
.st_size
;
563 p
->index_base
= idx_map
;
566 p
->pack_local
= local
;
567 if ((path_len
> 44) && !get_sha1_hex(path
+ path_len
- 44, sha1
))
568 hashcpy(p
->sha1
, sha1
);
572 struct packed_git
*parse_pack_index(unsigned char *sha1
)
574 char *path
= sha1_pack_index_name(sha1
);
575 return parse_pack_index_file(sha1
, path
);
578 struct packed_git
*parse_pack_index_file(const unsigned char *sha1
, char *idx_path
)
580 struct packed_git
*p
;
581 unsigned long idx_size
;
585 if (check_packed_git_idx(idx_path
, &idx_size
, &idx_map
))
588 path
= sha1_pack_name(sha1
);
590 p
= xmalloc(sizeof(*p
) + strlen(path
) + 2);
591 strcpy(p
->pack_name
, path
);
592 p
->index_size
= idx_size
;
594 p
->index_base
= idx_map
;
597 hashcpy(p
->sha1
, sha1
);
601 void install_packed_git(struct packed_git
*pack
)
603 pack
->next
= packed_git
;
607 static void prepare_packed_git_one(char *objdir
, int local
)
614 sprintf(path
, "%s/pack", objdir
);
619 error("unable to open object pack directory: %s: %s",
620 path
, strerror(errno
));
624 while ((de
= readdir(dir
)) != NULL
) {
625 int namelen
= strlen(de
->d_name
);
626 struct packed_git
*p
;
628 if (!has_extension(de
->d_name
, ".idx"))
631 /* we have .idx. Is it a file we can map? */
632 strcpy(path
+ len
, de
->d_name
);
633 for (p
= packed_git
; p
; p
= p
->next
) {
634 if (!memcmp(path
, p
->pack_name
, len
+ namelen
- 4))
639 p
= add_packed_git(path
, len
+ namelen
, local
);
642 p
->next
= packed_git
;
648 static int prepare_packed_git_run_once
= 0;
649 void prepare_packed_git(void)
651 struct alternate_object_database
*alt
;
653 if (prepare_packed_git_run_once
)
655 prepare_packed_git_one(get_object_directory(), 1);
657 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
659 prepare_packed_git_one(alt
->base
, 0);
662 prepare_packed_git_run_once
= 1;
665 void reprepare_packed_git(void)
667 prepare_packed_git_run_once
= 0;
668 prepare_packed_git();
671 int check_sha1_signature(const unsigned char *sha1
, void *map
, unsigned long size
, const char *type
)
673 unsigned char real_sha1
[20];
674 hash_sha1_file(map
, size
, type
, real_sha1
);
675 return hashcmp(sha1
, real_sha1
) ? -1 : 0;
678 void *map_sha1_file(const unsigned char *sha1
, unsigned long *size
)
683 char *filename
= find_sha1_file(sha1
, &st
);
689 fd
= open(filename
, O_RDONLY
| sha1_file_open_flag
);
691 /* See if it works without O_NOATIME */
692 switch (sha1_file_open_flag
) {
694 fd
= open(filename
, O_RDONLY
);
702 /* If it failed once, it will probably fail again.
703 * Stop using O_NOATIME
705 sha1_file_open_flag
= 0;
707 map
= mmap(NULL
, st
.st_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
709 if (map
== MAP_FAILED
)
715 int legacy_loose_object(unsigned char *map
)
720 * Is it a zlib-compressed buffer? If so, the first byte
721 * must be 0x78 (15-bit window size, deflated), and the
722 * first 16-bit word is evenly divisible by 31
724 word
= (map
[0] << 8) + map
[1];
725 if (map
[0] == 0x78 && !(word
% 31))
731 unsigned long unpack_object_header_gently(const unsigned char *buf
, unsigned long len
, enum object_type
*type
, unsigned long *sizep
)
736 unsigned long used
= 0;
739 *type
= (c
>> 4) & 7;
745 if (sizeof(long) * 8 <= shift
)
748 size
+= (c
& 0x7f) << shift
;
755 static int unpack_sha1_header(z_stream
*stream
, unsigned char *map
, unsigned long mapsize
, void *buffer
, unsigned long bufsiz
)
757 unsigned long size
, used
;
758 static const char valid_loose_object_type
[8] = {
760 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
761 0, /* "delta" and others are invalid in a loose object */
763 enum object_type type
;
765 /* Get the data stream */
766 memset(stream
, 0, sizeof(*stream
));
767 stream
->next_in
= map
;
768 stream
->avail_in
= mapsize
;
769 stream
->next_out
= buffer
;
770 stream
->avail_out
= bufsiz
;
772 if (legacy_loose_object(map
)) {
774 return inflate(stream
, 0);
777 used
= unpack_object_header_gently(map
, mapsize
, &type
, &size
);
778 if (!used
|| !valid_loose_object_type
[type
])
783 /* Set up the stream for the rest.. */
784 stream
->next_in
= map
;
785 stream
->avail_in
= mapsize
;
788 /* And generate the fake traditional header */
789 stream
->total_out
= 1 + snprintf(buffer
, bufsiz
, "%s %lu",
790 type_names
[type
], size
);
794 static void *unpack_sha1_rest(z_stream
*stream
, void *buffer
, unsigned long size
)
796 int bytes
= strlen(buffer
) + 1;
797 unsigned char *buf
= xmalloc(1+size
);
800 n
= stream
->total_out
- bytes
;
803 memcpy(buf
, (char *) buffer
+ bytes
, n
);
806 stream
->next_out
= buf
+ bytes
;
807 stream
->avail_out
= size
- bytes
;
808 while (inflate(stream
, Z_FINISH
) == Z_OK
)
817 * We used to just use "sscanf()", but that's actually way
818 * too permissive for what we want to check. So do an anal
819 * object header parse by hand.
821 static int parse_sha1_header(char *hdr
, char *type
, unsigned long *sizep
)
827 * The type can be at most ten bytes (including the
828 * terminating '\0' that we add), and is followed by
843 * The length must follow immediately, and be in canonical
844 * decimal format (ie "010" is not valid).
851 unsigned long c
= *hdr
- '0';
855 size
= size
* 10 + c
;
861 * The length must be followed by a zero byte
863 return *hdr
? -1 : 0;
866 void * unpack_sha1_file(void *map
, unsigned long mapsize
, char *type
, unsigned long *size
)
872 ret
= unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
));
873 if (ret
< Z_OK
|| parse_sha1_header(hdr
, type
, size
) < 0)
876 return unpack_sha1_rest(&stream
, hdr
, *size
);
879 static unsigned long get_delta_base(struct packed_git
*p
,
880 unsigned long offset
,
881 enum object_type kind
,
882 unsigned long delta_obj_offset
,
883 unsigned long *base_obj_offset
)
885 unsigned char *base_info
= p
->windows
->base
+ offset
;
886 unsigned long base_offset
;
888 /* there must be at least 20 bytes left regardless of delta type */
889 if (p
->pack_size
<= offset
+ 20)
890 die("truncated pack file");
892 if (kind
== OBJ_OFS_DELTA
) {
894 unsigned char c
= base_info
[used
++];
895 base_offset
= c
& 127;
898 if (!base_offset
|| base_offset
& ~(~0UL >> 7))
899 die("offset value overflow for delta base object");
900 c
= base_info
[used
++];
901 base_offset
= (base_offset
<< 7) + (c
& 127);
903 base_offset
= delta_obj_offset
- base_offset
;
904 if (base_offset
>= delta_obj_offset
)
905 die("delta base offset out of bound");
907 } else if (kind
== OBJ_REF_DELTA
) {
908 /* The base entry _must_ be in the same pack */
909 base_offset
= find_pack_entry_one(base_info
, p
);
911 die("failed to find delta-pack base object %s",
912 sha1_to_hex(base_info
));
915 die("I am totally screwed");
916 *base_obj_offset
= base_offset
;
920 /* forward declaration for a mutually recursive function */
921 static int packed_object_info(struct packed_git
*p
, unsigned long offset
,
922 char *type
, unsigned long *sizep
);
924 static int packed_delta_info(struct packed_git
*p
,
925 unsigned long offset
,
926 enum object_type kind
,
927 unsigned long obj_offset
,
929 unsigned long *sizep
)
931 unsigned long base_offset
;
933 offset
= get_delta_base(p
, offset
, kind
, obj_offset
, &base_offset
);
935 /* We choose to only get the type of the base object and
936 * ignore potentially corrupt pack file that expects the delta
937 * based on a base with a wrong size. This saves tons of
940 if (packed_object_info(p
, base_offset
, type
, NULL
))
941 die("cannot get info for delta-pack base");
944 const unsigned char *data
;
945 unsigned char delta_head
[20];
946 unsigned long result_size
;
950 memset(&stream
, 0, sizeof(stream
));
952 stream
.next_in
= p
->windows
->base
+ offset
;
953 stream
.avail_in
= p
->pack_size
- offset
;
954 stream
.next_out
= delta_head
;
955 stream
.avail_out
= sizeof(delta_head
);
957 inflateInit(&stream
);
958 st
= inflate(&stream
, Z_FINISH
);
960 if ((st
!= Z_STREAM_END
) &&
961 stream
.total_out
!= sizeof(delta_head
))
962 die("delta data unpack-initial failed");
964 /* Examine the initial part of the delta to figure out
969 /* ignore base size */
970 get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
972 /* Read the result size */
973 result_size
= get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
974 *sizep
= result_size
;
979 static unsigned long unpack_object_header(struct packed_git
*p
, unsigned long offset
,
980 enum object_type
*type
, unsigned long *sizep
)
984 if (p
->pack_size
<= offset
)
985 die("object offset outside of pack file");
987 used
= unpack_object_header_gently(p
->windows
->base
+ offset
,
988 p
->pack_size
- offset
, type
, sizep
);
990 die("object offset outside of pack file");
992 return offset
+ used
;
995 void packed_object_info_detail(struct packed_git
*p
,
996 unsigned long offset
,
999 unsigned long *store_size
,
1000 unsigned int *delta_chain_length
,
1001 unsigned char *base_sha1
)
1003 unsigned long obj_offset
, val
;
1004 unsigned char *next_sha1
;
1005 enum object_type kind
;
1007 *delta_chain_length
= 0;
1008 obj_offset
= offset
;
1009 offset
= unpack_object_header(p
, offset
, &kind
, size
);
1014 die("pack %s contains unknown object type %d",
1015 p
->pack_name
, kind
);
1020 strcpy(type
, type_names
[kind
]);
1021 *store_size
= 0; /* notyet */
1024 get_delta_base(p
, offset
, kind
, obj_offset
, &offset
);
1025 if (*delta_chain_length
== 0) {
1026 /* TODO: find base_sha1 as pointed by offset */
1030 if (p
->pack_size
<= offset
+ 20)
1031 die("pack file %s records an incomplete delta base",
1033 next_sha1
= p
->windows
->base
+ offset
;
1034 if (*delta_chain_length
== 0)
1035 hashcpy(base_sha1
, next_sha1
);
1036 offset
= find_pack_entry_one(next_sha1
, p
);
1039 obj_offset
= offset
;
1040 offset
= unpack_object_header(p
, offset
, &kind
, &val
);
1041 (*delta_chain_length
)++;
1045 static int packed_object_info(struct packed_git
*p
, unsigned long offset
,
1046 char *type
, unsigned long *sizep
)
1048 unsigned long size
, obj_offset
= offset
;
1049 enum object_type kind
;
1051 offset
= unpack_object_header(p
, offset
, &kind
, &size
);
1056 return packed_delta_info(p
, offset
, kind
, obj_offset
, type
, sizep
);
1061 strcpy(type
, type_names
[kind
]);
1064 die("pack %s contains unknown object type %d",
1065 p
->pack_name
, kind
);
1072 static void *unpack_compressed_entry(struct packed_git
*p
,
1073 unsigned long offset
,
1078 unsigned char *buffer
;
1080 buffer
= xmalloc(size
+ 1);
1082 memset(&stream
, 0, sizeof(stream
));
1083 stream
.next_in
= p
->windows
->base
+ offset
;
1084 stream
.avail_in
= p
->pack_size
- offset
;
1085 stream
.next_out
= buffer
;
1086 stream
.avail_out
= size
;
1088 inflateInit(&stream
);
1089 st
= inflate(&stream
, Z_FINISH
);
1090 inflateEnd(&stream
);
1091 if ((st
!= Z_STREAM_END
) || stream
.total_out
!= size
) {
1099 static void *unpack_delta_entry(struct packed_git
*p
,
1100 unsigned long offset
,
1101 unsigned long delta_size
,
1102 enum object_type kind
,
1103 unsigned long obj_offset
,
1105 unsigned long *sizep
)
1107 void *delta_data
, *result
, *base
;
1108 unsigned long result_size
, base_size
, base_offset
;
1110 offset
= get_delta_base(p
, offset
, kind
, obj_offset
, &base_offset
);
1111 base
= unpack_entry(p
, base_offset
, type
, &base_size
);
1113 die("failed to read delta base object at %lu from %s",
1114 base_offset
, p
->pack_name
);
1116 delta_data
= unpack_compressed_entry(p
, offset
, delta_size
);
1117 result
= patch_delta(base
, base_size
,
1118 delta_data
, delta_size
,
1121 die("failed to apply delta");
1124 *sizep
= result_size
;
1128 void *unpack_entry(struct packed_git
*p
, unsigned long offset
,
1129 char *type
, unsigned long *sizep
)
1131 unsigned long size
, obj_offset
= offset
;
1132 enum object_type kind
;
1135 if (use_packed_git(p
))
1136 die("cannot map packed file");
1137 offset
= unpack_object_header(p
, offset
, &kind
, &size
);
1141 retval
= unpack_delta_entry(p
, offset
, size
, kind
, obj_offset
, type
, sizep
);
1147 strcpy(type
, type_names
[kind
]);
1149 retval
= unpack_compressed_entry(p
, offset
, size
);
1152 die("unknown object type %i in %s", kind
, p
->pack_name
);
1154 unuse_packed_git(p
);
1158 int num_packed_objects(const struct packed_git
*p
)
1160 /* See check_packed_git_idx() */
1161 return (p
->index_size
- 20 - 20 - 4*256) / 24;
1164 int nth_packed_object_sha1(const struct packed_git
*p
, int n
,
1165 unsigned char* sha1
)
1167 void *index
= p
->index_base
+ 256;
1168 if (n
< 0 || num_packed_objects(p
) <= n
)
1170 hashcpy(sha1
, (unsigned char *) index
+ (24 * n
) + 4);
1174 unsigned long find_pack_entry_one(const unsigned char *sha1
,
1175 struct packed_git
*p
)
1177 unsigned int *level1_ofs
= p
->index_base
;
1178 int hi
= ntohl(level1_ofs
[*sha1
]);
1179 int lo
= ((*sha1
== 0x0) ? 0 : ntohl(level1_ofs
[*sha1
- 1]));
1180 void *index
= p
->index_base
+ 256;
1183 int mi
= (lo
+ hi
) / 2;
1184 int cmp
= hashcmp((unsigned char *)index
+ (24 * mi
) + 4, sha1
);
1186 return ntohl(*((unsigned int *) ((char *) index
+ (24 * mi
))));
1195 static int matches_pack_name(struct packed_git
*p
, const char *ig
)
1197 const char *last_c
, *c
;
1199 if (!strcmp(p
->pack_name
, ig
))
1202 for (c
= p
->pack_name
, last_c
= c
; *c
;)
1207 if (!strcmp(last_c
, ig
))
1213 static int find_pack_entry(const unsigned char *sha1
, struct pack_entry
*e
, const char **ignore_packed
)
1215 struct packed_git
*p
;
1216 unsigned long offset
;
1218 prepare_packed_git();
1220 for (p
= packed_git
; p
; p
= p
->next
) {
1221 if (ignore_packed
) {
1223 for (ig
= ignore_packed
; *ig
; ig
++)
1224 if (!matches_pack_name(p
, *ig
))
1229 offset
= find_pack_entry_one(sha1
, p
);
1233 hashcpy(e
->sha1
, sha1
);
1240 struct packed_git
*find_sha1_pack(const unsigned char *sha1
,
1241 struct packed_git
*packs
)
1243 struct packed_git
*p
;
1245 for (p
= packs
; p
; p
= p
->next
) {
1246 if (find_pack_entry_one(sha1
, p
))
1253 static int sha1_loose_object_info(const unsigned char *sha1
, char *type
, unsigned long *sizep
)
1256 unsigned long mapsize
, size
;
1261 map
= map_sha1_file(sha1
, &mapsize
);
1263 return error("unable to find %s", sha1_to_hex(sha1
));
1264 if (unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
)) < 0)
1265 status
= error("unable to unpack %s header",
1267 if (parse_sha1_header(hdr
, type
, &size
) < 0)
1268 status
= error("unable to parse %s header", sha1_to_hex(sha1
));
1274 inflateEnd(&stream
);
1275 munmap(map
, mapsize
);
1279 int sha1_object_info(const unsigned char *sha1
, char *type
, unsigned long *sizep
)
1282 struct pack_entry e
;
1284 if (!find_pack_entry(sha1
, &e
, NULL
)) {
1285 reprepare_packed_git();
1286 if (!find_pack_entry(sha1
, &e
, NULL
))
1287 return sha1_loose_object_info(sha1
, type
, sizep
);
1289 if (use_packed_git(e
.p
))
1290 die("cannot map packed file");
1291 status
= packed_object_info(e
.p
, e
.offset
, type
, sizep
);
1292 unuse_packed_git(e
.p
);
1296 static void *read_packed_sha1(const unsigned char *sha1
, char *type
, unsigned long *size
)
1298 struct pack_entry e
;
1300 if (!find_pack_entry(sha1
, &e
, NULL
)) {
1301 error("cannot read sha1_file for %s", sha1_to_hex(sha1
));
1304 return unpack_entry(e
.p
, e
.offset
, type
, size
);
1307 void * read_sha1_file(const unsigned char *sha1
, char *type
, unsigned long *size
)
1309 unsigned long mapsize
;
1311 struct pack_entry e
;
1313 if (find_pack_entry(sha1
, &e
, NULL
))
1314 return read_packed_sha1(sha1
, type
, size
);
1315 map
= map_sha1_file(sha1
, &mapsize
);
1317 buf
= unpack_sha1_file(map
, mapsize
, type
, size
);
1318 munmap(map
, mapsize
);
1321 reprepare_packed_git();
1322 if (find_pack_entry(sha1
, &e
, NULL
))
1323 return read_packed_sha1(sha1
, type
, size
);
1327 void *read_object_with_reference(const unsigned char *sha1
,
1328 const char *required_type
,
1329 unsigned long *size
,
1330 unsigned char *actual_sha1_return
)
1334 unsigned long isize
;
1335 unsigned char actual_sha1
[20];
1337 hashcpy(actual_sha1
, sha1
);
1339 int ref_length
= -1;
1340 const char *ref_type
= NULL
;
1342 buffer
= read_sha1_file(actual_sha1
, type
, &isize
);
1345 if (!strcmp(type
, required_type
)) {
1347 if (actual_sha1_return
)
1348 hashcpy(actual_sha1_return
, actual_sha1
);
1351 /* Handle references */
1352 else if (!strcmp(type
, commit_type
))
1354 else if (!strcmp(type
, tag_type
))
1355 ref_type
= "object ";
1360 ref_length
= strlen(ref_type
);
1362 if (memcmp(buffer
, ref_type
, ref_length
) ||
1363 get_sha1_hex((char *) buffer
+ ref_length
, actual_sha1
)) {
1368 /* Now we have the ID of the referred-to object in
1369 * actual_sha1. Check again. */
1373 static void write_sha1_file_prepare(void *buf
, unsigned long len
,
1374 const char *type
, unsigned char *sha1
,
1375 unsigned char *hdr
, int *hdrlen
)
1379 /* Generate the header */
1380 *hdrlen
= sprintf((char *)hdr
, "%s %lu", type
, len
)+1;
1384 SHA1_Update(&c
, hdr
, *hdrlen
);
1385 SHA1_Update(&c
, buf
, len
);
1386 SHA1_Final(sha1
, &c
);
1390 * Link the tempfile to the final place, possibly creating the
1391 * last directory level as you do so.
1393 * Returns the errno on failure, 0 on success.
1395 static int link_temp_to_file(const char *tmpfile
, const char *filename
)
1400 if (!link(tmpfile
, filename
))
1404 * Try to mkdir the last path component if that failed.
1406 * Re-try the "link()" regardless of whether the mkdir
1407 * succeeds, since a race might mean that somebody
1411 dir
= strrchr(filename
, '/');
1414 if (!mkdir(filename
, 0777) && adjust_shared_perm(filename
)) {
1419 if (!link(tmpfile
, filename
))
1427 * Move the just written object into its final resting place
1429 int move_temp_to_file(const char *tmpfile
, const char *filename
)
1431 int ret
= link_temp_to_file(tmpfile
, filename
);
1434 * Coda hack - coda doesn't like cross-directory links,
1435 * so we fall back to a rename, which will mean that it
1436 * won't be able to check collisions, but that's not a
1439 * The same holds for FAT formatted media.
1441 * When this succeeds, we just return 0. We have nothing
1444 if (ret
&& ret
!= EEXIST
) {
1445 if (!rename(tmpfile
, filename
))
1451 if (ret
!= EEXIST
) {
1452 return error("unable to write sha1 filename %s: %s\n", filename
, strerror(ret
));
1454 /* FIXME!!! Collision check here ? */
1460 static int write_buffer(int fd
, const void *buf
, size_t len
)
1465 size
= write(fd
, buf
, len
);
1467 return error("file write: disk full");
1469 if (errno
== EINTR
|| errno
== EAGAIN
)
1471 return error("file write error (%s)", strerror(errno
));
1474 buf
= (char *) buf
+ size
;
1479 static int write_binary_header(unsigned char *hdr
, enum object_type type
, unsigned long len
)
1484 c
= (type
<< 4) | (len
& 15);
1497 static void setup_object_header(z_stream
*stream
, const char *type
, unsigned long len
)
1501 if (use_legacy_headers
) {
1502 while (deflate(stream
, 0) == Z_OK
)
1506 if (!strcmp(type
, blob_type
))
1507 obj_type
= OBJ_BLOB
;
1508 else if (!strcmp(type
, tree_type
))
1509 obj_type
= OBJ_TREE
;
1510 else if (!strcmp(type
, commit_type
))
1511 obj_type
= OBJ_COMMIT
;
1512 else if (!strcmp(type
, tag_type
))
1515 die("trying to generate bogus object of type '%s'", type
);
1516 hdr
= write_binary_header(stream
->next_out
, obj_type
, len
);
1517 stream
->total_out
= hdr
;
1518 stream
->next_out
+= hdr
;
1519 stream
->avail_out
-= hdr
;
1522 int hash_sha1_file(void *buf
, unsigned long len
, const char *type
,
1523 unsigned char *sha1
)
1525 unsigned char hdr
[50];
1527 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
1531 int write_sha1_file(void *buf
, unsigned long len
, const char *type
, unsigned char *returnsha1
)
1534 unsigned char *compressed
;
1536 unsigned char sha1
[20];
1538 static char tmpfile
[PATH_MAX
];
1539 unsigned char hdr
[50];
1542 /* Normally if we have it in the pack then we do not bother writing
1543 * it out into .git/objects/??/?{38} file.
1545 write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
1546 filename
= sha1_file_name(sha1
);
1548 hashcpy(returnsha1
, sha1
);
1549 if (has_sha1_file(sha1
))
1551 fd
= open(filename
, O_RDONLY
);
1554 * FIXME!!! We might do collision checking here, but we'd
1555 * need to uncompress the old file and check it. Later.
1561 if (errno
!= ENOENT
) {
1562 return error("sha1 file %s: %s\n", filename
, strerror(errno
));
1565 snprintf(tmpfile
, sizeof(tmpfile
), "%s/obj_XXXXXX", get_object_directory());
1567 fd
= mkstemp(tmpfile
);
1570 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
1572 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile
, strerror(errno
));
1576 memset(&stream
, 0, sizeof(stream
));
1577 deflateInit(&stream
, zlib_compression_level
);
1578 size
= 8 + deflateBound(&stream
, len
+hdrlen
);
1579 compressed
= xmalloc(size
);
1582 stream
.next_out
= compressed
;
1583 stream
.avail_out
= size
;
1585 /* First header.. */
1586 stream
.next_in
= hdr
;
1587 stream
.avail_in
= hdrlen
;
1588 setup_object_header(&stream
, type
, len
);
1590 /* Then the data itself.. */
1591 stream
.next_in
= buf
;
1592 stream
.avail_in
= len
;
1593 while (deflate(&stream
, Z_FINISH
) == Z_OK
)
1595 deflateEnd(&stream
);
1596 size
= stream
.total_out
;
1598 if (write_buffer(fd
, compressed
, size
) < 0)
1599 die("unable to write sha1 file");
1604 return move_temp_to_file(tmpfile
, filename
);
1608 * We need to unpack and recompress the object for writing
1609 * it out to a different file.
1611 static void *repack_object(const unsigned char *sha1
, unsigned long *objsize
)
1615 unsigned char *unpacked
;
1622 /* need to unpack and recompress it by itself */
1623 unpacked
= read_packed_sha1(sha1
, type
, &len
);
1625 hdrlen
= sprintf(hdr
, "%s %lu", type
, len
) + 1;
1628 memset(&stream
, 0, sizeof(stream
));
1629 deflateInit(&stream
, zlib_compression_level
);
1630 size
= deflateBound(&stream
, len
+ hdrlen
);
1631 buf
= xmalloc(size
);
1634 stream
.next_out
= buf
;
1635 stream
.avail_out
= size
;
1637 /* First header.. */
1638 stream
.next_in
= (void *)hdr
;
1639 stream
.avail_in
= hdrlen
;
1640 while (deflate(&stream
, 0) == Z_OK
)
1643 /* Then the data itself.. */
1644 stream
.next_in
= unpacked
;
1645 stream
.avail_in
= len
;
1646 while (deflate(&stream
, Z_FINISH
) == Z_OK
)
1648 deflateEnd(&stream
);
1651 *objsize
= stream
.total_out
;
1655 int write_sha1_to_fd(int fd
, const unsigned char *sha1
)
1658 unsigned long objsize
;
1659 void *buf
= map_sha1_file(sha1
, &objsize
);
1662 retval
= write_buffer(fd
, buf
, objsize
);
1663 munmap(buf
, objsize
);
1667 buf
= repack_object(sha1
, &objsize
);
1668 retval
= write_buffer(fd
, buf
, objsize
);
1673 int write_sha1_from_fd(const unsigned char *sha1
, int fd
, char *buffer
,
1674 size_t bufsize
, size_t *bufposn
)
1676 char tmpfile
[PATH_MAX
];
1679 unsigned char real_sha1
[20];
1680 unsigned char discard
[4096];
1684 snprintf(tmpfile
, sizeof(tmpfile
), "%s/obj_XXXXXX", get_object_directory());
1686 local
= mkstemp(tmpfile
);
1689 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
1691 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile
, strerror(errno
));
1694 memset(&stream
, 0, sizeof(stream
));
1696 inflateInit(&stream
);
1703 stream
.avail_in
= *bufposn
;
1704 stream
.next_in
= (unsigned char *) buffer
;
1706 stream
.next_out
= discard
;
1707 stream
.avail_out
= sizeof(discard
);
1708 ret
= inflate(&stream
, Z_SYNC_FLUSH
);
1709 SHA1_Update(&c
, discard
, sizeof(discard
) -
1711 } while (stream
.avail_in
&& ret
== Z_OK
);
1712 if (write_buffer(local
, buffer
, *bufposn
- stream
.avail_in
) < 0)
1713 die("unable to write sha1 file");
1714 memmove(buffer
, buffer
+ *bufposn
- stream
.avail_in
,
1716 *bufposn
= stream
.avail_in
;
1720 size
= read(fd
, buffer
+ *bufposn
, bufsize
- *bufposn
);
1725 return error("Connection closed?");
1726 perror("Reading from connection");
1731 inflateEnd(&stream
);
1734 SHA1_Final(real_sha1
, &c
);
1735 if (ret
!= Z_STREAM_END
) {
1737 return error("File %s corrupted", sha1_to_hex(sha1
));
1739 if (hashcmp(sha1
, real_sha1
)) {
1741 return error("File %s has bad hash", sha1_to_hex(sha1
));
1744 return move_temp_to_file(tmpfile
, sha1_file_name(sha1
));
1747 int has_pack_index(const unsigned char *sha1
)
1750 if (stat(sha1_pack_index_name(sha1
), &st
))
1755 int has_pack_file(const unsigned char *sha1
)
1758 if (stat(sha1_pack_name(sha1
), &st
))
1763 int has_sha1_pack(const unsigned char *sha1
, const char **ignore_packed
)
1765 struct pack_entry e
;
1766 return find_pack_entry(sha1
, &e
, ignore_packed
);
1769 int has_sha1_file(const unsigned char *sha1
)
1772 struct pack_entry e
;
1774 if (find_pack_entry(sha1
, &e
, NULL
))
1776 return find_sha1_file(sha1
, &st
) ? 1 : 0;
1780 * reads from fd as long as possible into a supplied buffer of size bytes.
1781 * If necessary the buffer's size is increased using realloc()
1783 * returns 0 if anything went fine and -1 otherwise
1785 * NOTE: both buf and size may change, but even when -1 is returned
1786 * you still have to free() it yourself.
1788 int read_pipe(int fd
, char** return_buf
, unsigned long* return_size
)
1790 char* buf
= *return_buf
;
1791 unsigned long size
= *return_size
;
1793 unsigned long off
= 0;
1796 iret
= xread(fd
, buf
+ off
, size
- off
);
1801 buf
= xrealloc(buf
, size
);
1814 int index_pipe(unsigned char *sha1
, int fd
, const char *type
, int write_object
)
1816 unsigned long size
= 4096;
1817 char *buf
= xmalloc(size
);
1820 if (read_pipe(fd
, &buf
, &size
)) {
1828 ret
= write_sha1_file(buf
, size
, type
, sha1
);
1830 ret
= hash_sha1_file(buf
, size
, type
, sha1
);
1835 int index_fd(unsigned char *sha1
, int fd
, struct stat
*st
, int write_object
, const char *type
)
1837 unsigned long size
= st
->st_size
;
1843 buf
= mmap(NULL
, size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
1845 if (buf
== MAP_FAILED
)
1851 ret
= write_sha1_file(buf
, size
, type
, sha1
);
1853 ret
= hash_sha1_file(buf
, size
, type
, sha1
);
1859 int index_path(unsigned char *sha1
, const char *path
, struct stat
*st
, int write_object
)
1864 switch (st
->st_mode
& S_IFMT
) {
1866 fd
= open(path
, O_RDONLY
);
1868 return error("open(\"%s\"): %s", path
,
1870 if (index_fd(sha1
, fd
, st
, write_object
, NULL
) < 0)
1871 return error("%s: failed to insert into database",
1875 target
= xmalloc(st
->st_size
+1);
1876 if (readlink(path
, target
, st
->st_size
+1) != st
->st_size
) {
1877 char *errstr
= strerror(errno
);
1879 return error("readlink(\"%s\"): %s", path
,
1883 hash_sha1_file(target
, st
->st_size
, blob_type
, sha1
);
1884 else if (write_sha1_file(target
, st
->st_size
, blob_type
, sha1
))
1885 return error("%s: failed to insert into database",
1890 return error("%s: unsupported file type", path
);