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] = { 0, };
27 static unsigned int sha1_file_open_flag
= O_NOATIME
;
29 static unsigned hexval(char c
)
31 if (c
>= '0' && c
<= '9')
33 if (c
>= 'a' && c
<= 'f')
35 if (c
>= 'A' && c
<= 'F')
40 int get_sha1_hex(const char *hex
, unsigned char *sha1
)
43 for (i
= 0; i
< 20; i
++) {
44 unsigned int val
= (hexval(hex
[0]) << 4) | hexval(hex
[1]);
53 int safe_create_leading_directories(char *path
)
62 pos
= strchr(pos
, '/');
66 if (!stat(path
, &st
)) {
68 if (!S_ISDIR(st
.st_mode
)) {
73 else if (mkdir(path
, 0777)) {
77 else if (adjust_shared_perm(path
)) {
86 char * sha1_to_hex(const unsigned char *sha1
)
89 static char hexbuffer
[4][50];
90 static const char hex
[] = "0123456789abcdef";
91 char *buffer
= hexbuffer
[3 & ++bufno
], *buf
= buffer
;
94 for (i
= 0; i
< 20; i
++) {
95 unsigned int val
= *sha1
++;
96 *buf
++ = hex
[val
>> 4];
97 *buf
++ = hex
[val
& 0xf];
104 static void fill_sha1_path(char *pathbuf
, const unsigned char *sha1
)
107 for (i
= 0; i
< 20; i
++) {
108 static char hex
[] = "0123456789abcdef";
109 unsigned int val
= sha1
[i
];
110 char *pos
= pathbuf
+ i
*2 + (i
> 0);
111 *pos
++ = hex
[val
>> 4];
112 *pos
= hex
[val
& 0xf];
117 * NOTE! This returns a statically allocated buffer, so you have to be
118 * careful about using it. Do a "strdup()" if you need to save the
121 * Also note that this returns the location for creating. Reading
122 * SHA1 file can happen from any alternate directory listed in the
123 * DB_ENVIRONMENT environment variable if it is not found in
124 * the primary object database.
126 char *sha1_file_name(const unsigned char *sha1
)
128 static char *name
, *base
;
129 static const char *last_objdir
;
130 const char *sha1_file_directory
= get_object_directory();
132 if (!last_objdir
|| strcmp(last_objdir
, sha1_file_directory
)) {
133 int len
= strlen(sha1_file_directory
);
136 base
= xmalloc(len
+ 60);
137 memcpy(base
, sha1_file_directory
, len
);
138 memset(base
+len
, 0, 60);
141 name
= base
+ len
+ 1;
143 free((char *) last_objdir
);
144 last_objdir
= strdup(sha1_file_directory
);
146 fill_sha1_path(name
, sha1
);
150 char *sha1_pack_name(const unsigned char *sha1
)
152 static const char hex
[] = "0123456789abcdef";
153 static char *name
, *base
, *buf
;
154 static const char *last_objdir
;
155 const char *sha1_file_directory
= get_object_directory();
158 if (!last_objdir
|| strcmp(last_objdir
, sha1_file_directory
)) {
159 int len
= strlen(sha1_file_directory
);
162 base
= xmalloc(len
+ 60);
163 sprintf(base
, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory
);
164 name
= base
+ len
+ 11;
166 free((char *) last_objdir
);
167 last_objdir
= strdup(sha1_file_directory
);
172 for (i
= 0; i
< 20; i
++) {
173 unsigned int val
= *sha1
++;
174 *buf
++ = hex
[val
>> 4];
175 *buf
++ = hex
[val
& 0xf];
181 char *sha1_pack_index_name(const unsigned char *sha1
)
183 static const char hex
[] = "0123456789abcdef";
184 static char *name
, *base
, *buf
;
185 static const char *last_objdir
;
186 const char *sha1_file_directory
= get_object_directory();
189 if (!last_objdir
|| strcmp(last_objdir
, sha1_file_directory
)) {
190 int len
= strlen(sha1_file_directory
);
193 base
= xmalloc(len
+ 60);
194 sprintf(base
, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory
);
195 name
= base
+ len
+ 11;
197 free((char *) last_objdir
);
198 last_objdir
= strdup(sha1_file_directory
);
203 for (i
= 0; i
< 20; i
++) {
204 unsigned int val
= *sha1
++;
205 *buf
++ = hex
[val
>> 4];
206 *buf
++ = hex
[val
& 0xf];
212 struct alternate_object_database
*alt_odb_list
;
213 static struct alternate_object_database
**alt_odb_tail
;
215 static void read_info_alternates(const char * alternates
, int depth
);
218 * Prepare alternate object database registry.
220 * The variable alt_odb_list points at the list of struct
221 * alternate_object_database. The elements on this list come from
222 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
223 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
224 * whose contents is similar to that environment variable but can be
225 * LF separated. Its base points at a statically allocated buffer that
226 * contains "/the/directory/corresponding/to/.git/objects/...", while
227 * its name points just after the slash at the end of ".git/objects/"
228 * in the example above, and has enough space to hold 40-byte hex
229 * SHA1, an extra slash for the first level indirection, and the
232 static int link_alt_odb_entry(const char * entry
, int len
, const char * relative_base
, int depth
)
235 const char *objdir
= get_object_directory();
236 struct alternate_object_database
*ent
;
237 struct alternate_object_database
*alt
;
238 /* 43 = 40-byte + 2 '/' + terminating NUL */
240 int entlen
= pfxlen
+ 43;
243 if (*entry
!= '/' && relative_base
) {
244 /* Relative alt-odb */
246 base_len
= strlen(relative_base
) + 1;
250 ent
= xmalloc(sizeof(*ent
) + entlen
);
252 if (*entry
!= '/' && relative_base
) {
253 memcpy(ent
->base
, relative_base
, base_len
- 1);
254 ent
->base
[base_len
- 1] = '/';
255 memcpy(ent
->base
+ base_len
, entry
, len
);
258 memcpy(ent
->base
, entry
, pfxlen
);
260 ent
->name
= ent
->base
+ pfxlen
+ 1;
261 ent
->base
[pfxlen
+ 3] = '/';
262 ent
->base
[pfxlen
] = ent
->base
[entlen
-1] = 0;
264 /* Detect cases where alternate disappeared */
265 if (stat(ent
->base
, &st
) || !S_ISDIR(st
.st_mode
)) {
266 error("object directory %s does not exist; "
267 "check .git/objects/info/alternates.",
273 /* Prevent the common mistake of listing the same
274 * thing twice, or object directory itself.
276 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
277 if (!memcmp(ent
->base
, alt
->base
, pfxlen
)) {
282 if (!memcmp(ent
->base
, objdir
, pfxlen
)) {
287 /* add the alternate entry */
289 alt_odb_tail
= &(ent
->next
);
292 /* recursively add alternates */
293 read_info_alternates(ent
->base
, depth
+ 1);
295 ent
->base
[pfxlen
] = '/';
300 static void link_alt_odb_entries(const char *alt
, const char *ep
, int sep
,
301 const char *relative_base
, int depth
)
303 const char *cp
, *last
;
306 error("%s: ignoring alternate object stores, nesting too deep.",
314 if (cp
< ep
&& *cp
== '#') {
315 while (cp
< ep
&& *cp
!= sep
)
320 while (cp
< ep
&& *cp
!= sep
)
323 if ((*last
!= '/') && depth
) {
324 error("%s: ignoring relative alternate object store %s",
325 relative_base
, last
);
327 link_alt_odb_entry(last
, cp
- last
,
328 relative_base
, depth
);
331 while (cp
< ep
&& *cp
== sep
)
337 static void read_info_alternates(const char * relative_base
, int depth
)
344 sprintf(path
, "%s/info/alternates", relative_base
);
345 fd
= open(path
, O_RDONLY
);
348 if (fstat(fd
, &st
) || (st
.st_size
== 0)) {
352 map
= mmap(NULL
, st
.st_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
354 if (map
== MAP_FAILED
)
357 link_alt_odb_entries(map
, map
+ st
.st_size
, '\n', relative_base
, depth
);
359 munmap(map
, st
.st_size
);
362 void prepare_alt_odb(void)
366 alt
= getenv(ALTERNATE_DB_ENVIRONMENT
);
371 alt_odb_tail
= &alt_odb_list
;
372 link_alt_odb_entries(alt
, alt
+ strlen(alt
), ':', NULL
, 0);
374 read_info_alternates(get_object_directory(), 0);
377 static char *find_sha1_file(const unsigned char *sha1
, struct stat
*st
)
379 char *name
= sha1_file_name(sha1
);
380 struct alternate_object_database
*alt
;
385 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
387 fill_sha1_path(name
, sha1
);
388 if (!stat(alt
->base
, st
))
394 #define PACK_MAX_SZ (1<<26)
395 static int pack_used_ctr
;
396 static unsigned long pack_mapped
;
397 struct packed_git
*packed_git
;
399 static int check_packed_git_idx(const char *path
, unsigned long *idx_size_
,
404 unsigned long idx_size
;
406 int fd
= open(path
, O_RDONLY
);
410 if (fstat(fd
, &st
)) {
414 idx_size
= st
.st_size
;
415 idx_map
= mmap(NULL
, idx_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
417 if (idx_map
== MAP_FAILED
)
422 *idx_size_
= idx_size
;
424 /* check index map */
425 if (idx_size
< 4*256 + 20 + 20)
426 return error("index file too small");
428 for (i
= 0; i
< 256; i
++) {
429 unsigned int n
= ntohl(index
[i
]);
431 return error("non-monotonic index");
437 * - 256 index entries 4 bytes each
438 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
439 * - 20-byte SHA1 of the packfile
440 * - 20-byte SHA1 file checksum
442 if (idx_size
!= 4*256 + nr
* 24 + 20 + 20)
443 return error("wrong index file size");
448 static int unuse_one_packed_git(void)
450 struct packed_git
*p
, *lru
= NULL
;
452 for (p
= packed_git
; p
; p
= p
->next
) {
453 if (p
->pack_use_cnt
|| !p
->pack_base
)
455 if (!lru
|| p
->pack_last_used
< lru
->pack_last_used
)
460 munmap(lru
->pack_base
, lru
->pack_size
);
461 lru
->pack_base
= NULL
;
465 void unuse_packed_git(struct packed_git
*p
)
470 int use_packed_git(struct packed_git
*p
)
474 /* We created the struct before we had the pack */
475 stat(p
->pack_name
, &st
);
476 if (!S_ISREG(st
.st_mode
))
477 die("packfile %s not a regular file", p
->pack_name
);
478 p
->pack_size
= st
.st_size
;
485 pack_mapped
+= p
->pack_size
;
486 while (PACK_MAX_SZ
< pack_mapped
&& unuse_one_packed_git())
488 fd
= open(p
->pack_name
, O_RDONLY
);
490 die("packfile %s cannot be opened", p
->pack_name
);
491 if (fstat(fd
, &st
)) {
493 die("packfile %s cannot be opened", p
->pack_name
);
495 if (st
.st_size
!= p
->pack_size
)
496 die("packfile %s size mismatch.", p
->pack_name
);
497 map
= mmap(NULL
, p
->pack_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
499 if (map
== MAP_FAILED
)
500 die("packfile %s cannot be mapped.", p
->pack_name
);
503 /* Check if the pack file matches with the index file.
506 if (memcmp((char*)(p
->index_base
) + p
->index_size
- 40,
507 (char *) p
->pack_base
+ p
->pack_size
- 20,
510 die("packfile %s does not match index.", p
->pack_name
);
513 p
->pack_last_used
= pack_used_ctr
++;
518 struct packed_git
*add_packed_git(char *path
, int path_len
, int local
)
521 struct packed_git
*p
;
522 unsigned long idx_size
;
524 unsigned char sha1
[20];
526 if (check_packed_git_idx(path
, &idx_size
, &idx_map
))
529 /* do we have a corresponding .pack file? */
530 strcpy(path
+ path_len
- 4, ".pack");
531 if (stat(path
, &st
) || !S_ISREG(st
.st_mode
)) {
532 munmap(idx_map
, idx_size
);
535 /* ok, it looks sane as far as we can check without
536 * actually mapping the pack file.
538 p
= xmalloc(sizeof(*p
) + path_len
+ 2);
539 strcpy(p
->pack_name
, path
);
540 p
->index_size
= idx_size
;
541 p
->pack_size
= st
.st_size
;
542 p
->index_base
= idx_map
;
545 p
->pack_last_used
= 0;
547 p
->pack_local
= local
;
548 if ((path_len
> 44) && !get_sha1_hex(path
+ path_len
- 44, sha1
))
549 memcpy(p
->sha1
, sha1
, 20);
553 struct packed_git
*parse_pack_index(unsigned char *sha1
)
555 char *path
= sha1_pack_index_name(sha1
);
556 return parse_pack_index_file(sha1
, path
);
559 struct packed_git
*parse_pack_index_file(const unsigned char *sha1
, char *idx_path
)
561 struct packed_git
*p
;
562 unsigned long idx_size
;
566 if (check_packed_git_idx(idx_path
, &idx_size
, &idx_map
))
569 path
= sha1_pack_name(sha1
);
571 p
= xmalloc(sizeof(*p
) + strlen(path
) + 2);
572 strcpy(p
->pack_name
, path
);
573 p
->index_size
= idx_size
;
575 p
->index_base
= idx_map
;
578 p
->pack_last_used
= 0;
580 memcpy(p
->sha1
, sha1
, 20);
584 void install_packed_git(struct packed_git
*pack
)
586 pack
->next
= packed_git
;
590 static void prepare_packed_git_one(char *objdir
, int local
)
597 sprintf(path
, "%s/pack", objdir
);
602 error("unable to open object pack directory: %s: %s",
603 path
, strerror(errno
));
607 while ((de
= readdir(dir
)) != NULL
) {
608 int namelen
= strlen(de
->d_name
);
609 struct packed_git
*p
;
611 if (!has_extension(de
->d_name
, ".idx"))
614 /* we have .idx. Is it a file we can map? */
615 strcpy(path
+ len
, de
->d_name
);
616 for (p
= packed_git
; p
; p
= p
->next
) {
617 if (!memcmp(path
, p
->pack_name
, len
+ namelen
- 4))
622 p
= add_packed_git(path
, len
+ namelen
, local
);
625 p
->next
= packed_git
;
631 static int prepare_packed_git_run_once
= 0;
632 void prepare_packed_git(void)
634 struct alternate_object_database
*alt
;
636 if (prepare_packed_git_run_once
)
638 prepare_packed_git_one(get_object_directory(), 1);
640 for (alt
= alt_odb_list
; alt
; alt
= alt
->next
) {
642 prepare_packed_git_one(alt
->base
, 0);
645 prepare_packed_git_run_once
= 1;
648 static void reprepare_packed_git(void)
650 prepare_packed_git_run_once
= 0;
651 prepare_packed_git();
654 int check_sha1_signature(const unsigned char *sha1
, void *map
, unsigned long size
, const char *type
)
657 unsigned char real_sha1
[20];
661 SHA1_Update(&c
, header
, 1+sprintf(header
, "%s %lu", type
, size
));
662 SHA1_Update(&c
, map
, size
);
663 SHA1_Final(real_sha1
, &c
);
664 return memcmp(sha1
, real_sha1
, 20) ? -1 : 0;
667 void *map_sha1_file(const unsigned char *sha1
, unsigned long *size
)
672 char *filename
= find_sha1_file(sha1
, &st
);
678 fd
= open(filename
, O_RDONLY
| sha1_file_open_flag
);
680 /* See if it works without O_NOATIME */
681 switch (sha1_file_open_flag
) {
683 fd
= open(filename
, O_RDONLY
);
691 /* If it failed once, it will probably fail again.
692 * Stop using O_NOATIME
694 sha1_file_open_flag
= 0;
696 map
= mmap(NULL
, st
.st_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
698 if (map
== MAP_FAILED
)
704 int legacy_loose_object(unsigned char *map
)
709 * Is it a zlib-compressed buffer? If so, the first byte
710 * must be 0x78 (15-bit window size, deflated), and the
711 * first 16-bit word is evenly divisible by 31
713 word
= (map
[0] << 8) + map
[1];
714 if (map
[0] == 0x78 && !(word
% 31))
720 static int unpack_sha1_header(z_stream
*stream
, unsigned char *map
, unsigned long mapsize
, void *buffer
, unsigned long bufsiz
)
725 static const char *typename
[8] = {
727 "commit", "tree", "blob", "tag",
732 /* Get the data stream */
733 memset(stream
, 0, sizeof(*stream
));
734 stream
->next_in
= map
;
735 stream
->avail_in
= mapsize
;
736 stream
->next_out
= buffer
;
737 stream
->avail_out
= bufsiz
;
739 if (legacy_loose_object(map
)) {
741 return inflate(stream
, 0);
746 type
= typename
[(c
>> 4) & 7];
753 if (bits
>= 8*sizeof(long))
756 size
+= (c
& 0x7f) << bits
;
761 /* Set up the stream for the rest.. */
762 stream
->next_in
= map
;
763 stream
->avail_in
= mapsize
;
766 /* And generate the fake traditional header */
767 stream
->total_out
= 1 + snprintf(buffer
, bufsiz
, "%s %lu", type
, size
);
771 static void *unpack_sha1_rest(z_stream
*stream
, void *buffer
, unsigned long size
)
773 int bytes
= strlen(buffer
) + 1;
774 unsigned char *buf
= xmalloc(1+size
);
777 n
= stream
->total_out
- bytes
;
780 memcpy(buf
, (char *) buffer
+ bytes
, n
);
783 stream
->next_out
= buf
+ bytes
;
784 stream
->avail_out
= size
- bytes
;
785 while (inflate(stream
, Z_FINISH
) == Z_OK
)
794 * We used to just use "sscanf()", but that's actually way
795 * too permissive for what we want to check. So do an anal
796 * object header parse by hand.
798 static int parse_sha1_header(char *hdr
, char *type
, unsigned long *sizep
)
804 * The type can be at most ten bytes (including the
805 * terminating '\0' that we add), and is followed by
820 * The length must follow immediately, and be in canonical
821 * decimal format (ie "010" is not valid).
828 unsigned long c
= *hdr
- '0';
832 size
= size
* 10 + c
;
838 * The length must be followed by a zero byte
840 return *hdr
? -1 : 0;
843 void * unpack_sha1_file(void *map
, unsigned long mapsize
, char *type
, unsigned long *size
)
849 ret
= unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
));
850 if (ret
< Z_OK
|| parse_sha1_header(hdr
, type
, size
) < 0)
853 return unpack_sha1_rest(&stream
, hdr
, *size
);
856 /* forward declaration for a mutually recursive function */
857 static int packed_object_info(struct pack_entry
*entry
,
858 char *type
, unsigned long *sizep
);
860 static int packed_delta_info(unsigned char *base_sha1
,
861 unsigned long delta_size
,
864 unsigned long *sizep
,
865 struct packed_git
*p
)
867 struct pack_entry base_ent
;
870 die("truncated pack file");
872 /* The base entry _must_ be in the same pack */
873 if (!find_pack_entry_one(base_sha1
, &base_ent
, p
))
874 die("failed to find delta-pack base object %s",
875 sha1_to_hex(base_sha1
));
877 /* We choose to only get the type of the base object and
878 * ignore potentially corrupt pack file that expects the delta
879 * based on a base with a wrong size. This saves tons of
883 if (packed_object_info(&base_ent
, type
, NULL
))
884 die("cannot get info for delta-pack base");
887 const unsigned char *data
;
888 unsigned char delta_head
[64];
889 unsigned long result_size
;
893 memset(&stream
, 0, sizeof(stream
));
895 data
= stream
.next_in
= base_sha1
+ 20;
896 stream
.avail_in
= left
- 20;
897 stream
.next_out
= delta_head
;
898 stream
.avail_out
= sizeof(delta_head
);
900 inflateInit(&stream
);
901 st
= inflate(&stream
, Z_FINISH
);
903 if ((st
!= Z_STREAM_END
) &&
904 stream
.total_out
!= sizeof(delta_head
))
905 die("delta data unpack-initial failed");
907 /* Examine the initial part of the delta to figure out
912 /* ignore base size */
913 get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
915 /* Read the result size */
916 result_size
= get_delta_hdr_size(&data
, delta_head
+sizeof(delta_head
));
917 *sizep
= result_size
;
922 static unsigned long unpack_object_header(struct packed_git
*p
, unsigned long offset
,
923 enum object_type
*type
, unsigned long *sizep
)
926 unsigned char *pack
, c
;
929 if (offset
>= p
->pack_size
)
930 die("object offset outside of pack file");
932 pack
= (unsigned char *) p
->pack_base
+ offset
;
935 *type
= (c
>> 4) & 7;
939 if (offset
>= p
->pack_size
)
940 die("object offset outside of pack file");
943 size
+= (c
& 0x7f) << shift
;
950 int check_reuse_pack_delta(struct packed_git
*p
, unsigned long offset
,
951 unsigned char *base
, unsigned long *sizep
,
952 enum object_type
*kindp
)
959 ptr
= unpack_object_header(p
, ptr
, kindp
, sizep
);
960 if (*kindp
!= OBJ_DELTA
)
962 memcpy(base
, (char *) p
->pack_base
+ ptr
, 20);
969 void packed_object_info_detail(struct pack_entry
*e
,
972 unsigned long *store_size
,
973 unsigned int *delta_chain_length
,
974 unsigned char *base_sha1
)
976 struct packed_git
*p
= e
->p
;
977 unsigned long offset
;
979 enum object_type kind
;
981 offset
= unpack_object_header(p
, e
->offset
, &kind
, size
);
982 pack
= (unsigned char *) p
->pack_base
+ offset
;
983 if (kind
!= OBJ_DELTA
)
984 *delta_chain_length
= 0;
986 unsigned int chain_length
= 0;
987 if (p
->pack_size
<= offset
+ 20)
988 die("pack file %s records an incomplete delta base",
990 memcpy(base_sha1
, pack
, 20);
992 struct pack_entry base_ent
;
995 find_pack_entry_one(pack
, &base_ent
, p
);
996 offset
= unpack_object_header(p
, base_ent
.offset
,
998 pack
= (unsigned char *) p
->pack_base
+ offset
;
1000 } while (kind
== OBJ_DELTA
);
1001 *delta_chain_length
= chain_length
;
1005 strcpy(type
, commit_type
);
1008 strcpy(type
, tree_type
);
1011 strcpy(type
, blob_type
);
1014 strcpy(type
, tag_type
);
1017 die("corrupted pack file %s containing object of kind %d",
1018 p
->pack_name
, kind
);
1020 *store_size
= 0; /* notyet */
1023 static int packed_object_info(struct pack_entry
*entry
,
1024 char *type
, unsigned long *sizep
)
1026 struct packed_git
*p
= entry
->p
;
1027 unsigned long offset
, size
, left
;
1028 unsigned char *pack
;
1029 enum object_type kind
;
1032 if (use_packed_git(p
))
1033 die("cannot map packed file");
1035 offset
= unpack_object_header(p
, entry
->offset
, &kind
, &size
);
1036 pack
= (unsigned char *) p
->pack_base
+ offset
;
1037 left
= p
->pack_size
- offset
;
1041 retval
= packed_delta_info(pack
, size
, left
, type
, sizep
, p
);
1042 unuse_packed_git(p
);
1045 strcpy(type
, commit_type
);
1048 strcpy(type
, tree_type
);
1051 strcpy(type
, blob_type
);
1054 strcpy(type
, tag_type
);
1057 die("corrupted pack file %s containing object of kind %d",
1058 p
->pack_name
, kind
);
1062 unuse_packed_git(p
);
1066 /* forward declaration for a mutually recursive function */
1067 static void *unpack_entry(struct pack_entry
*, char *, unsigned long *);
1069 static void *unpack_delta_entry(unsigned char *base_sha1
,
1070 unsigned long delta_size
,
1073 unsigned long *sizep
,
1074 struct packed_git
*p
)
1076 struct pack_entry base_ent
;
1077 void *data
, *delta_data
, *result
, *base
;
1078 unsigned long data_size
, result_size
, base_size
;
1083 die("truncated pack file");
1085 /* The base entry _must_ be in the same pack */
1086 if (!find_pack_entry_one(base_sha1
, &base_ent
, p
))
1087 die("failed to find delta-pack base object %s",
1088 sha1_to_hex(base_sha1
));
1089 base
= unpack_entry_gently(&base_ent
, type
, &base_size
);
1091 die("failed to read delta-pack base object %s",
1092 sha1_to_hex(base_sha1
));
1094 data
= base_sha1
+ 20;
1095 data_size
= left
- 20;
1096 delta_data
= xmalloc(delta_size
);
1098 memset(&stream
, 0, sizeof(stream
));
1100 stream
.next_in
= data
;
1101 stream
.avail_in
= data_size
;
1102 stream
.next_out
= delta_data
;
1103 stream
.avail_out
= delta_size
;
1105 inflateInit(&stream
);
1106 st
= inflate(&stream
, Z_FINISH
);
1107 inflateEnd(&stream
);
1108 if ((st
!= Z_STREAM_END
) || stream
.total_out
!= delta_size
)
1109 die("delta data unpack failed");
1111 result
= patch_delta(base
, base_size
,
1112 delta_data
, delta_size
,
1115 die("failed to apply delta");
1118 *sizep
= result_size
;
1122 static void *unpack_non_delta_entry(unsigned char *data
,
1128 unsigned char *buffer
;
1130 buffer
= xmalloc(size
+ 1);
1132 memset(&stream
, 0, sizeof(stream
));
1133 stream
.next_in
= data
;
1134 stream
.avail_in
= left
;
1135 stream
.next_out
= buffer
;
1136 stream
.avail_out
= size
;
1138 inflateInit(&stream
);
1139 st
= inflate(&stream
, Z_FINISH
);
1140 inflateEnd(&stream
);
1141 if ((st
!= Z_STREAM_END
) || stream
.total_out
!= size
) {
1149 static void *unpack_entry(struct pack_entry
*entry
,
1150 char *type
, unsigned long *sizep
)
1152 struct packed_git
*p
= entry
->p
;
1155 if (use_packed_git(p
))
1156 die("cannot map packed file");
1157 retval
= unpack_entry_gently(entry
, type
, sizep
);
1158 unuse_packed_git(p
);
1160 die("corrupted pack file %s", p
->pack_name
);
1164 /* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
1165 void *unpack_entry_gently(struct pack_entry
*entry
,
1166 char *type
, unsigned long *sizep
)
1168 struct packed_git
*p
= entry
->p
;
1169 unsigned long offset
, size
, left
;
1170 unsigned char *pack
;
1171 enum object_type kind
;
1174 offset
= unpack_object_header(p
, entry
->offset
, &kind
, &size
);
1175 pack
= (unsigned char *) p
->pack_base
+ offset
;
1176 left
= p
->pack_size
- offset
;
1179 retval
= unpack_delta_entry(pack
, size
, left
, type
, sizep
, p
);
1182 strcpy(type
, commit_type
);
1185 strcpy(type
, tree_type
);
1188 strcpy(type
, blob_type
);
1191 strcpy(type
, tag_type
);
1197 retval
= unpack_non_delta_entry(pack
, size
, left
);
1201 int num_packed_objects(const struct packed_git
*p
)
1203 /* See check_packed_git_idx() */
1204 return (p
->index_size
- 20 - 20 - 4*256) / 24;
1207 int nth_packed_object_sha1(const struct packed_git
*p
, int n
,
1208 unsigned char* sha1
)
1210 void *index
= p
->index_base
+ 256;
1211 if (n
< 0 || num_packed_objects(p
) <= n
)
1213 memcpy(sha1
, (char *) index
+ (24 * n
) + 4, 20);
1217 int find_pack_entry_one(const unsigned char *sha1
,
1218 struct pack_entry
*e
, struct packed_git
*p
)
1220 unsigned int *level1_ofs
= p
->index_base
;
1221 int hi
= ntohl(level1_ofs
[*sha1
]);
1222 int lo
= ((*sha1
== 0x0) ? 0 : ntohl(level1_ofs
[*sha1
- 1]));
1223 void *index
= p
->index_base
+ 256;
1226 int mi
= (lo
+ hi
) / 2;
1227 int cmp
= memcmp((char *) index
+ (24 * mi
) + 4, sha1
, 20);
1229 e
->offset
= ntohl(*((unsigned int *) ((char *) index
+ (24 * mi
))));
1230 memcpy(e
->sha1
, sha1
, 20);
1242 static int find_pack_entry(const unsigned char *sha1
, struct pack_entry
*e
)
1244 struct packed_git
*p
;
1245 prepare_packed_git();
1247 for (p
= packed_git
; p
; p
= p
->next
) {
1248 if (find_pack_entry_one(sha1
, e
, p
))
1254 struct packed_git
*find_sha1_pack(const unsigned char *sha1
,
1255 struct packed_git
*packs
)
1257 struct packed_git
*p
;
1258 struct pack_entry e
;
1260 for (p
= packs
; p
; p
= p
->next
) {
1261 if (find_pack_entry_one(sha1
, &e
, p
))
1268 int sha1_object_info(const unsigned char *sha1
, char *type
, unsigned long *sizep
)
1271 unsigned long mapsize
, size
;
1276 map
= map_sha1_file(sha1
, &mapsize
);
1278 struct pack_entry e
;
1280 if (find_pack_entry(sha1
, &e
))
1281 return packed_object_info(&e
, type
, sizep
);
1282 reprepare_packed_git();
1283 if (find_pack_entry(sha1
, &e
))
1284 return packed_object_info(&e
, type
, sizep
);
1285 return error("unable to find %s", sha1_to_hex(sha1
));
1287 if (unpack_sha1_header(&stream
, map
, mapsize
, hdr
, sizeof(hdr
)) < 0)
1288 status
= error("unable to unpack %s header",
1290 if (parse_sha1_header(hdr
, type
, &size
) < 0)
1291 status
= error("unable to parse %s header", sha1_to_hex(sha1
));
1297 inflateEnd(&stream
);
1298 munmap(map
, mapsize
);
1302 static void *read_packed_sha1(const unsigned char *sha1
, char *type
, unsigned long *size
)
1304 struct pack_entry e
;
1306 if (!find_pack_entry(sha1
, &e
)) {
1307 error("cannot read sha1_file for %s", sha1_to_hex(sha1
));
1310 return unpack_entry(&e
, type
, size
);
1313 void * read_sha1_file(const unsigned char *sha1
, char *type
, unsigned long *size
)
1315 unsigned long mapsize
;
1317 struct pack_entry e
;
1319 if (find_pack_entry(sha1
, &e
))
1320 return read_packed_sha1(sha1
, type
, size
);
1321 map
= map_sha1_file(sha1
, &mapsize
);
1323 buf
= unpack_sha1_file(map
, mapsize
, type
, size
);
1324 munmap(map
, mapsize
);
1327 reprepare_packed_git();
1328 if (find_pack_entry(sha1
, &e
))
1329 return read_packed_sha1(sha1
, type
, size
);
1333 void *read_object_with_reference(const unsigned char *sha1
,
1334 const char *required_type
,
1335 unsigned long *size
,
1336 unsigned char *actual_sha1_return
)
1340 unsigned long isize
;
1341 unsigned char actual_sha1
[20];
1343 memcpy(actual_sha1
, sha1
, 20);
1345 int ref_length
= -1;
1346 const char *ref_type
= NULL
;
1348 buffer
= read_sha1_file(actual_sha1
, type
, &isize
);
1351 if (!strcmp(type
, required_type
)) {
1353 if (actual_sha1_return
)
1354 memcpy(actual_sha1_return
, actual_sha1
, 20);
1357 /* Handle references */
1358 else if (!strcmp(type
, commit_type
))
1360 else if (!strcmp(type
, tag_type
))
1361 ref_type
= "object ";
1366 ref_length
= strlen(ref_type
);
1368 if (memcmp(buffer
, ref_type
, ref_length
) ||
1369 get_sha1_hex((char *) buffer
+ ref_length
, actual_sha1
)) {
1374 /* Now we have the ID of the referred-to object in
1375 * actual_sha1. Check again. */
1379 char *write_sha1_file_prepare(void *buf
,
1382 unsigned char *sha1
,
1388 /* Generate the header */
1389 *hdrlen
= sprintf((char *)hdr
, "%s %lu", type
, len
)+1;
1393 SHA1_Update(&c
, hdr
, *hdrlen
);
1394 SHA1_Update(&c
, buf
, len
);
1395 SHA1_Final(sha1
, &c
);
1397 return sha1_file_name(sha1
);
1401 * Link the tempfile to the final place, possibly creating the
1402 * last directory level as you do so.
1404 * Returns the errno on failure, 0 on success.
1406 static int link_temp_to_file(const char *tmpfile
, char *filename
)
1411 if (!link(tmpfile
, filename
))
1415 * Try to mkdir the last path component if that failed.
1417 * Re-try the "link()" regardless of whether the mkdir
1418 * succeeds, since a race might mean that somebody
1422 dir
= strrchr(filename
, '/');
1425 mkdir(filename
, 0777);
1426 if (adjust_shared_perm(filename
))
1429 if (!link(tmpfile
, filename
))
1437 * Move the just written object into its final resting place
1439 int move_temp_to_file(const char *tmpfile
, char *filename
)
1441 int ret
= link_temp_to_file(tmpfile
, filename
);
1444 * Coda hack - coda doesn't like cross-directory links,
1445 * so we fall back to a rename, which will mean that it
1446 * won't be able to check collisions, but that's not a
1449 * The same holds for FAT formatted media.
1451 * When this succeeds, we just return 0. We have nothing
1454 if (ret
&& ret
!= EEXIST
) {
1455 if (!rename(tmpfile
, filename
))
1461 if (ret
!= EEXIST
) {
1462 fprintf(stderr
, "unable to write sha1 filename %s: %s\n", filename
, strerror(ret
));
1465 /* FIXME!!! Collision check here ? */
1471 static int write_buffer(int fd
, const void *buf
, size_t len
)
1476 size
= write(fd
, buf
, len
);
1478 return error("file write: disk full");
1480 if (errno
== EINTR
|| errno
== EAGAIN
)
1482 return error("file write error (%s)", strerror(errno
));
1485 buf
= (char *) buf
+ size
;
1490 static int write_binary_header(unsigned char *hdr
, enum object_type type
, unsigned long len
)
1495 c
= (type
<< 4) | (len
& 15);
1508 static void setup_object_header(z_stream
*stream
, const char *type
, unsigned long len
)
1512 if (use_legacy_headers
) {
1513 while (deflate(stream
, 0) == Z_OK
)
1517 if (!strcmp(type
, blob_type
))
1518 obj_type
= OBJ_BLOB
;
1519 else if (!strcmp(type
, tree_type
))
1520 obj_type
= OBJ_TREE
;
1521 else if (!strcmp(type
, commit_type
))
1522 obj_type
= OBJ_COMMIT
;
1523 else if (!strcmp(type
, tag_type
))
1526 die("trying to generate bogus object of type '%s'", type
);
1527 hdr
= write_binary_header(stream
->next_out
, obj_type
, len
);
1528 stream
->total_out
= hdr
;
1529 stream
->next_out
+= hdr
;
1530 stream
->avail_out
-= hdr
;
1533 int write_sha1_file(void *buf
, unsigned long len
, const char *type
, unsigned char *returnsha1
)
1536 unsigned char *compressed
;
1538 unsigned char sha1
[20];
1540 static char tmpfile
[PATH_MAX
];
1541 unsigned char hdr
[50];
1544 /* Normally if we have it in the pack then we do not bother writing
1545 * it out into .git/objects/??/?{38} file.
1547 filename
= write_sha1_file_prepare(buf
, len
, type
, sha1
, hdr
, &hdrlen
);
1549 memcpy(returnsha1
, sha1
, 20);
1550 if (has_sha1_file(sha1
))
1552 fd
= open(filename
, O_RDONLY
);
1555 * FIXME!!! We might do collision checking here, but we'd
1556 * need to uncompress the old file and check it. Later.
1562 if (errno
!= ENOENT
) {
1563 fprintf(stderr
, "sha1 file %s: %s\n", filename
, strerror(errno
));
1567 snprintf(tmpfile
, sizeof(tmpfile
), "%s/obj_XXXXXX", get_object_directory());
1569 fd
= mkstemp(tmpfile
);
1571 fprintf(stderr
, "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
);
1688 return error("Couldn't open %s for %s",
1689 tmpfile
, sha1_to_hex(sha1
));
1691 memset(&stream
, 0, sizeof(stream
));
1693 inflateInit(&stream
);
1700 stream
.avail_in
= *bufposn
;
1701 stream
.next_in
= (unsigned char *) buffer
;
1703 stream
.next_out
= discard
;
1704 stream
.avail_out
= sizeof(discard
);
1705 ret
= inflate(&stream
, Z_SYNC_FLUSH
);
1706 SHA1_Update(&c
, discard
, sizeof(discard
) -
1708 } while (stream
.avail_in
&& ret
== Z_OK
);
1709 if (write_buffer(local
, buffer
, *bufposn
- stream
.avail_in
) < 0)
1710 die("unable to write sha1 file");
1711 memmove(buffer
, buffer
+ *bufposn
- stream
.avail_in
,
1713 *bufposn
= stream
.avail_in
;
1717 size
= read(fd
, buffer
+ *bufposn
, bufsize
- *bufposn
);
1722 return error("Connection closed?");
1723 perror("Reading from connection");
1728 inflateEnd(&stream
);
1731 SHA1_Final(real_sha1
, &c
);
1732 if (ret
!= Z_STREAM_END
) {
1734 return error("File %s corrupted", sha1_to_hex(sha1
));
1736 if (memcmp(sha1
, real_sha1
, 20)) {
1738 return error("File %s has bad hash", sha1_to_hex(sha1
));
1741 return move_temp_to_file(tmpfile
, sha1_file_name(sha1
));
1744 int has_pack_index(const unsigned char *sha1
)
1747 if (stat(sha1_pack_index_name(sha1
), &st
))
1752 int has_pack_file(const unsigned char *sha1
)
1755 if (stat(sha1_pack_name(sha1
), &st
))
1760 int has_sha1_pack(const unsigned char *sha1
)
1762 struct pack_entry e
;
1763 return find_pack_entry(sha1
, &e
);
1766 int has_sha1_file(const unsigned char *sha1
)
1769 struct pack_entry e
;
1771 if (find_pack_entry(sha1
, &e
))
1773 return find_sha1_file(sha1
, &st
) ? 1 : 0;
1777 * reads from fd as long as possible into a supplied buffer of size bytes.
1778 * If necessary the buffer's size is increased using realloc()
1780 * returns 0 if anything went fine and -1 otherwise
1782 * NOTE: both buf and size may change, but even when -1 is returned
1783 * you still have to free() it yourself.
1785 int read_pipe(int fd
, char** return_buf
, unsigned long* return_size
)
1787 char* buf
= *return_buf
;
1788 unsigned long size
= *return_size
;
1790 unsigned long off
= 0;
1793 iret
= xread(fd
, buf
+ off
, size
- off
);
1798 buf
= realloc(buf
, size
);
1811 int index_pipe(unsigned char *sha1
, int fd
, const char *type
, int write_object
)
1813 unsigned long size
= 4096;
1814 char *buf
= malloc(size
);
1816 unsigned char hdr
[50];
1819 if (read_pipe(fd
, &buf
, &size
)) {
1827 ret
= write_sha1_file(buf
, size
, type
, sha1
);
1829 write_sha1_file_prepare(buf
, size
, type
, sha1
, hdr
, &hdrlen
);
1836 int index_fd(unsigned char *sha1
, int fd
, struct stat
*st
, int write_object
, const char *type
)
1838 unsigned long size
= st
->st_size
;
1841 unsigned char hdr
[50];
1846 buf
= mmap(NULL
, size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
1848 if (buf
== MAP_FAILED
)
1854 ret
= write_sha1_file(buf
, size
, type
, sha1
);
1856 write_sha1_file_prepare(buf
, size
, type
, sha1
, hdr
, &hdrlen
);
1864 int index_path(unsigned char *sha1
, const char *path
, struct stat
*st
, int write_object
)
1869 switch (st
->st_mode
& S_IFMT
) {
1871 fd
= open(path
, O_RDONLY
);
1873 return error("open(\"%s\"): %s", path
,
1875 if (index_fd(sha1
, fd
, st
, write_object
, NULL
) < 0)
1876 return error("%s: failed to insert into database",
1880 target
= xmalloc(st
->st_size
+1);
1881 if (readlink(path
, target
, st
->st_size
+1) != st
->st_size
) {
1882 char *errstr
= strerror(errno
);
1884 return error("readlink(\"%s\"): %s", path
,
1887 if (!write_object
) {
1888 unsigned char hdr
[50];
1890 write_sha1_file_prepare(target
, st
->st_size
, blob_type
,
1891 sha1
, hdr
, &hdrlen
);
1892 } else if (write_sha1_file(target
, st
->st_size
, blob_type
, sha1
))
1893 return error("%s: failed to insert into database",
1898 return error("%s: unsupported file type", path
);