2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
6 * This handles basic git sha1 object files - packing, unpacking,
16 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
17 #define O_NOATIME 01000000
23 static unsigned int sha1_file_open_flag = O_NOATIME;
25 static unsigned hexval(char c)
27 if (c >= '0' && c <= '9')
29 if (c >= 'a' && c <= 'f')
31 if (c >= 'A' && c <= 'F')
36 int get_sha1_hex(const char *hex, unsigned char *sha1)
39 for (i = 0; i < 20; i++) {
40 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
49 static char *git_dir, *git_object_dir, *git_index_file, *git_refs_dir,
51 static void setup_git_env(void)
53 git_dir = gitenv(GIT_DIR_ENVIRONMENT);
55 git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
56 git_object_dir = gitenv(DB_ENVIRONMENT);
57 if (!git_object_dir) {
58 git_object_dir = xmalloc(strlen(git_dir) + 9);
59 sprintf(git_object_dir, "%s/objects", git_dir);
61 git_refs_dir = xmalloc(strlen(git_dir) + 6);
62 sprintf(git_refs_dir, "%s/refs", git_dir);
63 git_index_file = gitenv(INDEX_ENVIRONMENT);
64 if (!git_index_file) {
65 git_index_file = xmalloc(strlen(git_dir) + 7);
66 sprintf(git_index_file, "%s/index", git_dir);
68 git_graft_file = gitenv(GRAFT_ENVIRONMENT);
70 git_graft_file = strdup(git_path("info/grafts"));
73 char *get_object_directory(void)
77 return git_object_dir;
80 char *get_refs_directory(void)
87 char *get_index_file(void)
91 return git_index_file;
94 char *get_graft_file(void)
98 return git_graft_file;
101 int safe_create_leading_directories(char *path)
106 pos = strchr(pos, '/');
110 if (mkdir(path, 0777) < 0)
111 if (errno != EEXIST) {
120 char * sha1_to_hex(const unsigned char *sha1)
122 static char buffer[50];
123 static const char hex[] = "0123456789abcdef";
127 for (i = 0; i < 20; i++) {
128 unsigned int val = *sha1++;
129 *buf++ = hex[val >> 4];
130 *buf++ = hex[val & 0xf];
135 static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
138 for (i = 0; i < 20; i++) {
139 static char hex[] = "0123456789abcdef";
140 unsigned int val = sha1[i];
141 char *pos = pathbuf + i*2 + (i > 0);
142 *pos++ = hex[val >> 4];
143 *pos = hex[val & 0xf];
148 * NOTE! This returns a statically allocated buffer, so you have to be
149 * careful about using it. Do a "strdup()" if you need to save the
152 * Also note that this returns the location for creating. Reading
153 * SHA1 file can happen from any alternate directory listed in the
154 * DB_ENVIRONMENT environment variable if it is not found in
155 * the primary object database.
157 char *sha1_file_name(const unsigned char *sha1)
159 static char *name, *base;
162 const char *sha1_file_directory = get_object_directory();
163 int len = strlen(sha1_file_directory);
164 base = xmalloc(len + 60);
165 memcpy(base, sha1_file_directory, len);
166 memset(base+len, 0, 60);
169 name = base + len + 1;
171 fill_sha1_path(name, sha1);
175 char *sha1_pack_name(const unsigned char *sha1)
177 static const char hex[] = "0123456789abcdef";
178 static char *name, *base, *buf;
182 const char *sha1_file_directory = get_object_directory();
183 int len = strlen(sha1_file_directory);
184 base = xmalloc(len + 60);
185 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
186 name = base + len + 11;
191 for (i = 0; i < 20; i++) {
192 unsigned int val = *sha1++;
193 *buf++ = hex[val >> 4];
194 *buf++ = hex[val & 0xf];
200 char *sha1_pack_index_name(const unsigned char *sha1)
202 static const char hex[] = "0123456789abcdef";
203 static char *name, *base, *buf;
207 const char *sha1_file_directory = get_object_directory();
208 int len = strlen(sha1_file_directory);
209 base = xmalloc(len + 60);
210 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
211 name = base + len + 11;
216 for (i = 0; i < 20; i++) {
217 unsigned int val = *sha1++;
218 *buf++ = hex[val >> 4];
219 *buf++ = hex[val & 0xf];
225 struct alternate_object_database *alt_odb_list;
226 static struct alternate_object_database **alt_odb_tail;
229 * Prepare alternate object database registry.
231 * The variable alt_odb_list points at the list of struct
232 * alternate_object_database. The elements on this list come from
233 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
234 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
235 * whose contents is exactly in the same format as that environment
236 * variable. Its base points at a statically allocated buffer that
237 * contains "/the/directory/corresponding/to/.git/objects/...", while
238 * its name points just after the slash at the end of ".git/objects/"
239 * in the example above, and has enough space to hold 40-byte hex
240 * SHA1, an extra slash for the first level indirection, and the
243 static void link_alt_odb_entries(const char *alt, const char *ep)
245 const char *cp, *last;
246 struct alternate_object_database *ent;
250 for (cp = last; cp < ep && *cp != ':'; cp++)
253 /* 43 = 40-byte + 2 '/' + terminating NUL */
254 int pfxlen = cp - last;
255 int entlen = pfxlen + 43;
257 ent = xmalloc(sizeof(*ent) + entlen);
259 alt_odb_tail = &(ent->next);
262 memcpy(ent->base, last, pfxlen);
263 ent->name = ent->base + pfxlen + 1;
264 ent->base[pfxlen] = ent->base[pfxlen + 3] = '/';
265 ent->base[entlen-1] = 0;
267 while (cp < ep && *cp == ':')
273 void prepare_alt_odb(void)
279 char *alt = gitenv(ALTERNATE_DB_ENVIRONMENT) ? : "";
281 sprintf(path, "%s/info/alternates", get_object_directory());
284 alt_odb_tail = &alt_odb_list;
285 link_alt_odb_entries(alt, alt + strlen(alt));
287 fd = open(path, O_RDONLY);
290 if (fstat(fd, &st) || (st.st_size == 0)) {
294 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
296 if (map == MAP_FAILED)
299 /* Remove the trailing newline */
300 for (ep = map + st.st_size - 1; map < ep && ep[-1] == '\n'; ep--)
302 link_alt_odb_entries(map, ep);
303 munmap(map, st.st_size);
306 static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
308 char *name = sha1_file_name(sha1);
309 struct alternate_object_database *alt;
314 for (alt = alt_odb_list; alt; alt = alt->next) {
316 fill_sha1_path(name, sha1);
317 if (!stat(alt->base, st))
323 #define PACK_MAX_SZ (1<<26)
324 static int pack_used_ctr;
325 static unsigned long pack_mapped;
326 struct packed_git *packed_git;
328 static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
333 unsigned long idx_size;
335 int fd = open(path, O_RDONLY);
339 if (fstat(fd, &st)) {
343 idx_size = st.st_size;
344 idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
346 if (idx_map == MAP_FAILED)
351 *idx_size_ = idx_size;
353 /* check index map */
354 if (idx_size < 4*256 + 20 + 20)
355 return error("index file too small");
357 for (i = 0; i < 256; i++) {
358 unsigned int n = ntohl(index[i]);
360 return error("non-monotonic index");
366 * - 256 index entries 4 bytes each
367 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
368 * - 20-byte SHA1 of the packfile
369 * - 20-byte SHA1 file checksum
371 if (idx_size != 4*256 + nr * 24 + 20 + 20)
372 return error("wrong index file size");
377 static int unuse_one_packed_git(void)
379 struct packed_git *p, *lru = NULL;
381 for (p = packed_git; p; p = p->next) {
382 if (p->pack_use_cnt || !p->pack_base)
384 if (!lru || p->pack_last_used < lru->pack_last_used)
389 munmap(lru->pack_base, lru->pack_size);
390 lru->pack_base = NULL;
394 void unuse_packed_git(struct packed_git *p)
399 int use_packed_git(struct packed_git *p)
403 // We created the struct before we had the pack
404 stat(p->pack_name, &st);
405 if (!S_ISREG(st.st_mode))
406 die("packfile %s not a regular file", p->pack_name);
407 p->pack_size = st.st_size;
414 pack_mapped += p->pack_size;
415 while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
417 fd = open(p->pack_name, O_RDONLY);
419 die("packfile %s cannot be opened", p->pack_name);
420 if (fstat(fd, &st)) {
422 die("packfile %s cannot be opened", p->pack_name);
424 if (st.st_size != p->pack_size)
425 die("packfile %s size mismatch.", p->pack_name);
426 map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
428 if (map == MAP_FAILED)
429 die("packfile %s cannot be mapped.", p->pack_name);
432 /* Check if the pack file matches with the index file.
435 if (memcmp((char*)(p->index_base) + p->index_size - 40,
436 p->pack_base + p->pack_size - 20, 20)) {
438 die("packfile %s does not match index.", p->pack_name);
441 p->pack_last_used = pack_used_ctr++;
446 struct packed_git *add_packed_git(char *path, int path_len)
449 struct packed_git *p;
450 unsigned long idx_size;
453 if (check_packed_git_idx(path, &idx_size, &idx_map))
456 /* do we have a corresponding .pack file? */
457 strcpy(path + path_len - 4, ".pack");
458 if (stat(path, &st) || !S_ISREG(st.st_mode)) {
459 munmap(idx_map, idx_size);
462 /* ok, it looks sane as far as we can check without
463 * actually mapping the pack file.
465 p = xmalloc(sizeof(*p) + path_len + 2);
466 strcpy(p->pack_name, path);
467 p->index_size = idx_size;
468 p->pack_size = st.st_size;
469 p->index_base = idx_map;
472 p->pack_last_used = 0;
477 struct packed_git *parse_pack_index(unsigned char *sha1)
479 struct packed_git *p;
480 unsigned long idx_size;
482 char *path = sha1_pack_index_name(sha1);
484 if (check_packed_git_idx(path, &idx_size, &idx_map))
487 path = sha1_pack_name(sha1);
489 p = xmalloc(sizeof(*p) + strlen(path) + 2);
490 strcpy(p->pack_name, path);
491 p->index_size = idx_size;
493 p->index_base = idx_map;
496 p->pack_last_used = 0;
498 memcpy(p->sha1, sha1, 20);
502 void install_packed_git(struct packed_git *pack)
504 pack->next = packed_git;
508 static void prepare_packed_git_one(char *objdir)
515 sprintf(path, "%s/pack", objdir);
521 while ((de = readdir(dir)) != NULL) {
522 int namelen = strlen(de->d_name);
523 struct packed_git *p;
525 if (strcmp(de->d_name + namelen - 4, ".idx"))
528 /* we have .idx. Is it a file we can map? */
529 strcpy(path + len, de->d_name);
530 p = add_packed_git(path, len + namelen);
533 p->next = packed_git;
539 void prepare_packed_git(void)
541 static int run_once = 0;
542 struct alternate_object_database *alt;
546 prepare_packed_git_one(get_object_directory());
548 for (alt = alt_odb_list; alt; alt = alt->next) {
550 prepare_packed_git_one(alt->base);
555 int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
558 unsigned char real_sha1[20];
562 SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
563 SHA1_Update(&c, map, size);
564 SHA1_Final(real_sha1, &c);
565 return memcmp(sha1, real_sha1, 20) ? -1 : 0;
568 static void *map_sha1_file_internal(const unsigned char *sha1,
574 char *filename = find_sha1_file(sha1, &st);
580 fd = open(filename, O_RDONLY | sha1_file_open_flag);
582 /* See if it works without O_NOATIME */
583 switch (sha1_file_open_flag) {
585 fd = open(filename, O_RDONLY);
593 /* If it failed once, it will probably fail again.
594 * Stop using O_NOATIME
596 sha1_file_open_flag = 0;
598 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
600 if (map == MAP_FAILED)
606 int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size)
608 /* Get the data stream */
609 memset(stream, 0, sizeof(*stream));
610 stream->next_in = map;
611 stream->avail_in = mapsize;
612 stream->next_out = buffer;
613 stream->avail_out = size;
616 return inflate(stream, 0);
619 static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
621 int bytes = strlen(buffer) + 1;
622 unsigned char *buf = xmalloc(1+size);
624 memcpy(buf, buffer + bytes, stream->total_out - bytes);
625 bytes = stream->total_out - bytes;
627 stream->next_out = buf + bytes;
628 stream->avail_out = size - bytes;
629 while (inflate(stream, Z_FINISH) == Z_OK)
638 * We used to just use "sscanf()", but that's actually way
639 * too permissive for what we want to check. So do an anal
640 * object header parse by hand.
642 int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
648 * The type can be at most ten bytes (including the
649 * terminating '\0' that we add), and is followed by
664 * The length must follow immediately, and be in canonical
665 * decimal format (ie "010" is not valid).
672 unsigned long c = *hdr - '0';
676 size = size * 10 + c;
682 * The length must be followed by a zero byte
684 return *hdr ? -1 : 0;
687 void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
693 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
694 if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
697 return unpack_sha1_rest(&stream, hdr, *size);
700 /* forward declaration for a mutually recursive function */
701 static int packed_object_info(struct pack_entry *entry,
702 char *type, unsigned long *sizep);
704 static int packed_delta_info(unsigned char *base_sha1,
705 unsigned long delta_size,
708 unsigned long *sizep,
709 struct packed_git *p)
711 struct pack_entry base_ent;
714 die("truncated pack file");
716 /* The base entry _must_ be in the same pack */
717 if (!find_pack_entry_one(base_sha1, &base_ent, p))
718 die("failed to find delta-pack base object %s",
719 sha1_to_hex(base_sha1));
721 /* We choose to only get the type of the base object and
722 * ignore potentially corrupt pack file that expects the delta
723 * based on a base with a wrong size. This saves tons of
727 if (packed_object_info(&base_ent, type, NULL))
728 die("cannot get info for delta-pack base");
731 const unsigned char *data;
732 unsigned char delta_head[64];
733 unsigned long result_size;
737 memset(&stream, 0, sizeof(stream));
739 data = stream.next_in = base_sha1 + 20;
740 stream.avail_in = left - 20;
741 stream.next_out = delta_head;
742 stream.avail_out = sizeof(delta_head);
744 inflateInit(&stream);
745 st = inflate(&stream, Z_FINISH);
747 if ((st != Z_STREAM_END) &&
748 stream.total_out != sizeof(delta_head))
749 die("delta data unpack-initial failed");
751 /* Examine the initial part of the delta to figure out
755 get_delta_hdr_size(&data); /* ignore base size */
757 /* Read the result size */
758 result_size = get_delta_hdr_size(&data);
759 *sizep = result_size;
764 static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset,
765 enum object_type *type, unsigned long *sizep)
768 unsigned char *pack, c;
771 if (offset >= p->pack_size)
772 die("object offset outside of pack file");
774 pack = p->pack_base + offset;
777 *type = (c >> 4) & 7;
781 if (offset >= p->pack_size)
782 die("object offset outside of pack file");
785 size += (c & 0x7f) << shift;
792 void packed_object_info_detail(struct pack_entry *e,
795 unsigned long *store_size,
796 int *delta_chain_length,
797 unsigned char *base_sha1)
799 struct packed_git *p = e->p;
800 unsigned long offset, left;
802 enum object_type kind;
804 offset = unpack_object_header(p, e->offset, &kind, size);
805 pack = p->pack_base + offset;
806 left = p->pack_size - offset;
807 if (kind != OBJ_DELTA)
808 *delta_chain_length = 0;
810 int chain_length = 0;
811 memcpy(base_sha1, pack, 20);
813 struct pack_entry base_ent;
816 find_pack_entry_one(pack, &base_ent, p);
817 offset = unpack_object_header(p, base_ent.offset,
819 pack = p->pack_base + offset;
821 } while (kind == OBJ_DELTA);
822 *delta_chain_length = chain_length;
826 strcpy(type, "commit");
829 strcpy(type, "tree");
832 strcpy(type, "blob");
838 die("corrupted pack file");
840 *store_size = 0; /* notyet */
843 static int packed_object_info(struct pack_entry *entry,
844 char *type, unsigned long *sizep)
846 struct packed_git *p = entry->p;
847 unsigned long offset, size, left;
849 enum object_type kind;
852 if (use_packed_git(p))
853 die("cannot map packed file");
855 offset = unpack_object_header(p, entry->offset, &kind, &size);
856 pack = p->pack_base + offset;
857 left = p->pack_size - offset;
861 retval = packed_delta_info(pack, size, left, type, sizep, p);
865 strcpy(type, "commit");
868 strcpy(type, "tree");
871 strcpy(type, "blob");
877 die("corrupted pack file");
885 /* forward declaration for a mutually recursive function */
886 static void *unpack_entry(struct pack_entry *, char *, unsigned long *);
888 static void *unpack_delta_entry(unsigned char *base_sha1,
889 unsigned long delta_size,
892 unsigned long *sizep,
893 struct packed_git *p)
895 struct pack_entry base_ent;
896 void *data, *delta_data, *result, *base;
897 unsigned long data_size, result_size, base_size;
902 die("truncated pack file");
903 data = base_sha1 + 20;
904 data_size = left - 20;
905 delta_data = xmalloc(delta_size);
907 memset(&stream, 0, sizeof(stream));
909 stream.next_in = data;
910 stream.avail_in = data_size;
911 stream.next_out = delta_data;
912 stream.avail_out = delta_size;
914 inflateInit(&stream);
915 st = inflate(&stream, Z_FINISH);
917 if ((st != Z_STREAM_END) || stream.total_out != delta_size)
918 die("delta data unpack failed");
920 /* The base entry _must_ be in the same pack */
921 if (!find_pack_entry_one(base_sha1, &base_ent, p))
922 die("failed to find delta-pack base object %s",
923 sha1_to_hex(base_sha1));
924 base = unpack_entry_gently(&base_ent, type, &base_size);
926 die("failed to read delta-pack base object %s",
927 sha1_to_hex(base_sha1));
928 result = patch_delta(base, base_size,
929 delta_data, delta_size,
932 die("failed to apply delta");
935 *sizep = result_size;
939 static void *unpack_non_delta_entry(unsigned char *data,
945 unsigned char *buffer;
947 buffer = xmalloc(size + 1);
949 memset(&stream, 0, sizeof(stream));
950 stream.next_in = data;
951 stream.avail_in = left;
952 stream.next_out = buffer;
953 stream.avail_out = size;
955 inflateInit(&stream);
956 st = inflate(&stream, Z_FINISH);
958 if ((st != Z_STREAM_END) || stream.total_out != size) {
966 static void *unpack_entry(struct pack_entry *entry,
967 char *type, unsigned long *sizep)
969 struct packed_git *p = entry->p;
972 if (use_packed_git(p))
973 die("cannot map packed file");
974 retval = unpack_entry_gently(entry, type, sizep);
977 die("corrupted pack file");
981 /* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
982 void *unpack_entry_gently(struct pack_entry *entry,
983 char *type, unsigned long *sizep)
985 struct packed_git *p = entry->p;
986 unsigned long offset, size, left;
988 enum object_type kind;
991 offset = unpack_object_header(p, entry->offset, &kind, &size);
992 pack = p->pack_base + offset;
993 left = p->pack_size - offset;
996 retval = unpack_delta_entry(pack, size, left, type, sizep, p);
999 strcpy(type, "commit");
1002 strcpy(type, "tree");
1005 strcpy(type, "blob");
1008 strcpy(type, "tag");
1014 retval = unpack_non_delta_entry(pack, size, left);
1018 int num_packed_objects(const struct packed_git *p)
1020 /* See check_packed_git_idx() */
1021 return (p->index_size - 20 - 20 - 4*256) / 24;
1024 int nth_packed_object_sha1(const struct packed_git *p, int n,
1025 unsigned char* sha1)
1027 void *index = p->index_base + 256;
1028 if (n < 0 || num_packed_objects(p) <= n)
1030 memcpy(sha1, (index + 24 * n + 4), 20);
1034 int find_pack_entry_one(const unsigned char *sha1,
1035 struct pack_entry *e, struct packed_git *p)
1037 unsigned int *level1_ofs = p->index_base;
1038 int hi = ntohl(level1_ofs[*sha1]);
1039 int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
1040 void *index = p->index_base + 256;
1043 int mi = (lo + hi) / 2;
1044 int cmp = memcmp(index + 24 * mi + 4, sha1, 20);
1046 e->offset = ntohl(*((int*)(index + 24 * mi)));
1047 memcpy(e->sha1, sha1, 20);
1059 static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1061 struct packed_git *p;
1062 prepare_packed_git();
1064 for (p = packed_git; p; p = p->next) {
1065 if (find_pack_entry_one(sha1, e, p))
1071 struct packed_git *find_sha1_pack(const unsigned char *sha1,
1072 struct packed_git *packs)
1074 struct packed_git *p;
1075 struct pack_entry e;
1077 for (p = packs; p; p = p->next) {
1078 if (find_pack_entry_one(sha1, &e, p))
1085 int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
1088 unsigned long mapsize, size;
1093 map = map_sha1_file_internal(sha1, &mapsize);
1095 struct pack_entry e;
1097 if (!find_pack_entry(sha1, &e))
1098 return error("unable to find %s", sha1_to_hex(sha1));
1099 return packed_object_info(&e, type, sizep);
1101 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1102 status = error("unable to unpack %s header",
1104 if (parse_sha1_header(hdr, type, &size) < 0)
1105 status = error("unable to parse %s header", sha1_to_hex(sha1));
1111 inflateEnd(&stream);
1112 munmap(map, mapsize);
1116 static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
1118 struct pack_entry e;
1120 if (!find_pack_entry(sha1, &e)) {
1121 error("cannot read sha1_file for %s", sha1_to_hex(sha1));
1124 return unpack_entry(&e, type, size);
1127 void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
1129 unsigned long mapsize;
1131 struct pack_entry e;
1133 if (find_pack_entry(sha1, &e))
1134 return read_packed_sha1(sha1, type, size);
1135 map = map_sha1_file_internal(sha1, &mapsize);
1137 buf = unpack_sha1_file(map, mapsize, type, size);
1138 munmap(map, mapsize);
1144 void *read_object_with_reference(const unsigned char *sha1,
1145 const char *required_type,
1146 unsigned long *size,
1147 unsigned char *actual_sha1_return)
1151 unsigned long isize;
1152 unsigned char actual_sha1[20];
1154 memcpy(actual_sha1, sha1, 20);
1156 int ref_length = -1;
1157 const char *ref_type = NULL;
1159 buffer = read_sha1_file(actual_sha1, type, &isize);
1162 if (!strcmp(type, required_type)) {
1164 if (actual_sha1_return)
1165 memcpy(actual_sha1_return, actual_sha1, 20);
1168 /* Handle references */
1169 else if (!strcmp(type, "commit"))
1171 else if (!strcmp(type, "tag"))
1172 ref_type = "object ";
1177 ref_length = strlen(ref_type);
1179 if (memcmp(buffer, ref_type, ref_length) ||
1180 get_sha1_hex(buffer + ref_length, actual_sha1)) {
1185 /* Now we have the ID of the referred-to object in
1186 * actual_sha1. Check again. */
1190 char *write_sha1_file_prepare(void *buf,
1193 unsigned char *sha1,
1199 /* Generate the header */
1200 *hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1;
1204 SHA1_Update(&c, hdr, *hdrlen);
1205 SHA1_Update(&c, buf, len);
1206 SHA1_Final(sha1, &c);
1208 return sha1_file_name(sha1);
1211 int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
1214 unsigned char *compressed;
1216 unsigned char sha1[20];
1218 static char tmpfile[PATH_MAX];
1219 unsigned char hdr[50];
1220 int fd, hdrlen, ret;
1222 /* Normally if we have it in the pack then we do not bother writing
1223 * it out into .git/objects/??/?{38} file.
1225 filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1227 memcpy(returnsha1, sha1, 20);
1228 if (has_sha1_file(sha1))
1230 fd = open(filename, O_RDONLY);
1233 * FIXME!!! We might do collision checking here, but we'd
1234 * need to uncompress the old file and check it. Later.
1240 if (errno != ENOENT) {
1241 fprintf(stderr, "sha1 file %s: %s", filename, strerror(errno));
1245 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
1247 fd = mkstemp(tmpfile);
1249 fprintf(stderr, "unable to create temporary sha1 filename %s: %s", tmpfile, strerror(errno));
1254 memset(&stream, 0, sizeof(stream));
1255 deflateInit(&stream, Z_BEST_COMPRESSION);
1256 size = deflateBound(&stream, len+hdrlen);
1257 compressed = xmalloc(size);
1260 stream.next_out = compressed;
1261 stream.avail_out = size;
1263 /* First header.. */
1264 stream.next_in = hdr;
1265 stream.avail_in = hdrlen;
1266 while (deflate(&stream, 0) == Z_OK)
1269 /* Then the data itself.. */
1270 stream.next_in = buf;
1271 stream.avail_in = len;
1272 while (deflate(&stream, Z_FINISH) == Z_OK)
1274 deflateEnd(&stream);
1275 size = stream.total_out;
1277 if (write(fd, compressed, size) != size)
1278 die("unable to write file");
1283 ret = link(tmpfile, filename);
1288 * Coda hack - coda doesn't like cross-directory links,
1289 * so we fall back to a rename, which will mean that it
1290 * won't be able to check collisions, but that's not a
1293 * When this succeeds, we just return 0. We have nothing
1296 if (ret == EXDEV && !rename(tmpfile, filename))
1301 if (ret != EEXIST) {
1302 fprintf(stderr, "unable to write sha1 filename %s: %s", filename, strerror(ret));
1305 /* FIXME!!! Collision check here ? */
1311 int write_sha1_to_fd(int fd, const unsigned char *sha1)
1314 unsigned long objsize;
1316 void *map = map_sha1_file_internal(sha1, &objsize);
1318 void *temp_obj = NULL;
1322 unsigned char *unpacked;
1327 // need to unpack and recompress it by itself
1328 unpacked = read_packed_sha1(sha1, type, &len);
1330 hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
1333 memset(&stream, 0, sizeof(stream));
1334 deflateInit(&stream, Z_BEST_COMPRESSION);
1335 size = deflateBound(&stream, len + hdrlen);
1336 temp_obj = buf = xmalloc(size);
1339 stream.next_out = buf;
1340 stream.avail_out = size;
1342 /* First header.. */
1343 stream.next_in = (void *)hdr;
1344 stream.avail_in = hdrlen;
1345 while (deflate(&stream, 0) == Z_OK)
1348 /* Then the data itself.. */
1349 stream.next_in = unpacked;
1350 stream.avail_in = len;
1351 while (deflate(&stream, Z_FINISH) == Z_OK)
1353 deflateEnd(&stream);
1356 objsize = stream.total_out;
1360 size = write(fd, buf + posn, objsize - posn);
1363 fprintf(stderr, "write closed");
1370 } while (posn < objsize);
1373 munmap(map, objsize);
1380 int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
1381 size_t bufsize, size_t *bufposn)
1383 char *filename = sha1_file_name(sha1);
1387 unsigned char real_sha1[20];
1388 unsigned char discard[4096];
1392 local = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
1395 return error("Couldn't open %s\n", filename);
1397 memset(&stream, 0, sizeof(stream));
1399 inflateInit(&stream);
1406 stream.avail_in = *bufposn;
1407 stream.next_in = (unsigned char *) buffer;
1409 stream.next_out = discard;
1410 stream.avail_out = sizeof(discard);
1411 ret = inflate(&stream, Z_SYNC_FLUSH);
1412 SHA1_Update(&c, discard, sizeof(discard) -
1414 } while (stream.avail_in && ret == Z_OK);
1415 write(local, buffer, *bufposn - stream.avail_in);
1416 memmove(buffer, buffer + *bufposn - stream.avail_in,
1418 *bufposn = stream.avail_in;
1422 size = read(fd, buffer + *bufposn, bufsize - *bufposn);
1427 return error("Connection closed?");
1428 perror("Reading from connection");
1433 inflateEnd(&stream);
1436 SHA1_Final(real_sha1, &c);
1437 if (ret != Z_STREAM_END) {
1439 return error("File %s corrupted", sha1_to_hex(sha1));
1441 if (memcmp(sha1, real_sha1, 20)) {
1443 return error("File %s has bad hash\n", sha1_to_hex(sha1));
1449 int has_pack_index(const unsigned char *sha1)
1452 if (stat(sha1_pack_index_name(sha1), &st))
1457 int has_pack_file(const unsigned char *sha1)
1460 if (stat(sha1_pack_name(sha1), &st))
1465 int has_sha1_pack(const unsigned char *sha1)
1467 struct pack_entry e;
1468 return find_pack_entry(sha1, &e);
1471 int has_sha1_file(const unsigned char *sha1)
1474 struct pack_entry e;
1476 if (find_pack_entry(sha1, &e))
1478 return find_sha1_file(sha1, &st) ? 1 : 0;
1481 int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
1483 unsigned long size = st->st_size;
1486 unsigned char hdr[50];
1491 buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
1493 if (buf == MAP_FAILED)
1499 ret = write_sha1_file(buf, size, type, sha1);
1501 write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);