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 adjust_shared_perm(const char *path)
58 if (!shared_repository)
60 if (lstat(path, &st) < 0)
71 if (chmod(path, mode) < 0)
76 int safe_create_leading_directories(char *path)
85 pos = strchr(pos, '/');
89 if (!stat(path, &st)) {
91 if (!S_ISDIR(st.st_mode)) {
96 else if (mkdir(path, 0777)) {
100 else if (adjust_shared_perm(path)) {
109 char * sha1_to_hex(const unsigned char *sha1)
111 static char buffer[50];
112 static const char hex[] = "0123456789abcdef";
116 for (i = 0; i < 20; i++) {
117 unsigned int val = *sha1++;
118 *buf++ = hex[val >> 4];
119 *buf++ = hex[val & 0xf];
126 static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
129 for (i = 0; i < 20; i++) {
130 static char hex[] = "0123456789abcdef";
131 unsigned int val = sha1[i];
132 char *pos = pathbuf + i*2 + (i > 0);
133 *pos++ = hex[val >> 4];
134 *pos = hex[val & 0xf];
139 * NOTE! This returns a statically allocated buffer, so you have to be
140 * careful about using it. Do a "strdup()" if you need to save the
143 * Also note that this returns the location for creating. Reading
144 * SHA1 file can happen from any alternate directory listed in the
145 * DB_ENVIRONMENT environment variable if it is not found in
146 * the primary object database.
148 char *sha1_file_name(const unsigned char *sha1)
150 static char *name, *base;
153 const char *sha1_file_directory = get_object_directory();
154 int len = strlen(sha1_file_directory);
155 base = xmalloc(len + 60);
156 memcpy(base, sha1_file_directory, len);
157 memset(base+len, 0, 60);
160 name = base + len + 1;
162 fill_sha1_path(name, sha1);
166 char *sha1_pack_name(const unsigned char *sha1)
168 static const char hex[] = "0123456789abcdef";
169 static char *name, *base, *buf;
173 const char *sha1_file_directory = get_object_directory();
174 int len = strlen(sha1_file_directory);
175 base = xmalloc(len + 60);
176 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
177 name = base + len + 11;
182 for (i = 0; i < 20; i++) {
183 unsigned int val = *sha1++;
184 *buf++ = hex[val >> 4];
185 *buf++ = hex[val & 0xf];
191 char *sha1_pack_index_name(const unsigned char *sha1)
193 static const char hex[] = "0123456789abcdef";
194 static char *name, *base, *buf;
198 const char *sha1_file_directory = get_object_directory();
199 int len = strlen(sha1_file_directory);
200 base = xmalloc(len + 60);
201 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
202 name = base + len + 11;
207 for (i = 0; i < 20; i++) {
208 unsigned int val = *sha1++;
209 *buf++ = hex[val >> 4];
210 *buf++ = hex[val & 0xf];
216 struct alternate_object_database *alt_odb_list;
217 static struct alternate_object_database **alt_odb_tail;
220 * Prepare alternate object database registry.
222 * The variable alt_odb_list points at the list of struct
223 * alternate_object_database. The elements on this list come from
224 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
225 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
226 * whose contents is similar to that environment variable but can be
227 * LF separated. Its base points at a statically allocated buffer that
228 * contains "/the/directory/corresponding/to/.git/objects/...", while
229 * its name points just after the slash at the end of ".git/objects/"
230 * in the example above, and has enough space to hold 40-byte hex
231 * SHA1, an extra slash for the first level indirection, and the
234 static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
235 const char *relative_base)
237 const char *cp, *last;
238 struct alternate_object_database *ent;
239 const char *objdir = get_object_directory();
245 if (cp < ep && *cp == '#') {
246 while (cp < ep && *cp != sep)
251 for ( ; cp < ep && *cp != sep; cp++)
255 struct alternate_object_database *alt;
256 /* 43 = 40-byte + 2 '/' + terminating NUL */
257 int pfxlen = cp - last;
258 int entlen = pfxlen + 43;
260 if (*last != '/' && relative_base) {
261 /* Relative alt-odb */
263 base_len = strlen(relative_base) + 1;
267 ent = xmalloc(sizeof(*ent) + entlen);
269 if (*last != '/' && relative_base) {
270 memcpy(ent->base, relative_base, base_len - 1);
271 ent->base[base_len - 1] = '/';
272 memcpy(ent->base + base_len,
276 memcpy(ent->base, last, pfxlen);
278 ent->name = ent->base + pfxlen + 1;
279 ent->base[pfxlen + 3] = '/';
280 ent->base[pfxlen] = ent->base[entlen-1] = 0;
282 /* Detect cases where alternate disappeared */
283 if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
284 error("object directory %s does not exist; "
285 "check .git/objects/info/alternates.",
289 ent->base[pfxlen] = '/';
291 /* Prevent the common mistake of listing the same
292 * thing twice, or object directory itself.
294 for (alt = alt_odb_list; alt; alt = alt->next)
295 if (!memcmp(ent->base, alt->base, pfxlen))
297 if (!memcmp(ent->base, objdir, pfxlen)) {
303 alt_odb_tail = &(ent->next);
307 while (cp < ep && *cp == sep)
313 void prepare_alt_odb(void)
321 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
326 alt_odb_tail = &alt_odb_list;
327 link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL);
329 sprintf(path, "%s/info/alternates", get_object_directory());
330 fd = open(path, O_RDONLY);
333 if (fstat(fd, &st) || (st.st_size == 0)) {
337 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
339 if (map == MAP_FAILED)
342 link_alt_odb_entries(map, map + st.st_size, '\n',
343 get_object_directory());
344 munmap(map, st.st_size);
347 static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
349 char *name = sha1_file_name(sha1);
350 struct alternate_object_database *alt;
355 for (alt = alt_odb_list; alt; alt = alt->next) {
357 fill_sha1_path(name, sha1);
358 if (!stat(alt->base, st))
364 #define PACK_MAX_SZ (1<<26)
365 static int pack_used_ctr;
366 static unsigned long pack_mapped;
367 struct packed_git *packed_git;
369 static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
374 unsigned long idx_size;
376 int fd = open(path, O_RDONLY);
380 if (fstat(fd, &st)) {
384 idx_size = st.st_size;
385 idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
387 if (idx_map == MAP_FAILED)
392 *idx_size_ = idx_size;
394 /* check index map */
395 if (idx_size < 4*256 + 20 + 20)
396 return error("index file too small");
398 for (i = 0; i < 256; i++) {
399 unsigned int n = ntohl(index[i]);
401 return error("non-monotonic index");
407 * - 256 index entries 4 bytes each
408 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
409 * - 20-byte SHA1 of the packfile
410 * - 20-byte SHA1 file checksum
412 if (idx_size != 4*256 + nr * 24 + 20 + 20)
413 return error("wrong index file size");
418 static int unuse_one_packed_git(void)
420 struct packed_git *p, *lru = NULL;
422 for (p = packed_git; p; p = p->next) {
423 if (p->pack_use_cnt || !p->pack_base)
425 if (!lru || p->pack_last_used < lru->pack_last_used)
430 munmap(lru->pack_base, lru->pack_size);
431 lru->pack_base = NULL;
435 void unuse_packed_git(struct packed_git *p)
440 int use_packed_git(struct packed_git *p)
444 // We created the struct before we had the pack
445 stat(p->pack_name, &st);
446 if (!S_ISREG(st.st_mode))
447 die("packfile %s not a regular file", p->pack_name);
448 p->pack_size = st.st_size;
455 pack_mapped += p->pack_size;
456 while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
458 fd = open(p->pack_name, O_RDONLY);
460 die("packfile %s cannot be opened", p->pack_name);
461 if (fstat(fd, &st)) {
463 die("packfile %s cannot be opened", p->pack_name);
465 if (st.st_size != p->pack_size)
466 die("packfile %s size mismatch.", p->pack_name);
467 map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
469 if (map == MAP_FAILED)
470 die("packfile %s cannot be mapped.", p->pack_name);
473 /* Check if the pack file matches with the index file.
476 if (memcmp((char*)(p->index_base) + p->index_size - 40,
477 p->pack_base + p->pack_size - 20, 20)) {
479 die("packfile %s does not match index.", p->pack_name);
482 p->pack_last_used = pack_used_ctr++;
487 struct packed_git *add_packed_git(char *path, int path_len, int local)
490 struct packed_git *p;
491 unsigned long idx_size;
493 unsigned char sha1[20];
495 if (check_packed_git_idx(path, &idx_size, &idx_map))
498 /* do we have a corresponding .pack file? */
499 strcpy(path + path_len - 4, ".pack");
500 if (stat(path, &st) || !S_ISREG(st.st_mode)) {
501 munmap(idx_map, idx_size);
504 /* ok, it looks sane as far as we can check without
505 * actually mapping the pack file.
507 p = xmalloc(sizeof(*p) + path_len + 2);
508 strcpy(p->pack_name, path);
509 p->index_size = idx_size;
510 p->pack_size = st.st_size;
511 p->index_base = idx_map;
514 p->pack_last_used = 0;
516 p->pack_local = local;
517 if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
518 memcpy(p->sha1, sha1, 20);
522 struct packed_git *parse_pack_index(unsigned char *sha1)
524 char *path = sha1_pack_index_name(sha1);
525 return parse_pack_index_file(sha1, path);
528 struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
530 struct packed_git *p;
531 unsigned long idx_size;
535 if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
538 path = sha1_pack_name(sha1);
540 p = xmalloc(sizeof(*p) + strlen(path) + 2);
541 strcpy(p->pack_name, path);
542 p->index_size = idx_size;
544 p->index_base = idx_map;
547 p->pack_last_used = 0;
549 memcpy(p->sha1, sha1, 20);
553 void install_packed_git(struct packed_git *pack)
555 pack->next = packed_git;
559 static void prepare_packed_git_one(char *objdir, int local)
566 sprintf(path, "%s/pack", objdir);
571 error("unable to open object pack directory: %s: %s",
572 path, strerror(errno));
576 while ((de = readdir(dir)) != NULL) {
577 int namelen = strlen(de->d_name);
578 struct packed_git *p;
580 if (strcmp(de->d_name + namelen - 4, ".idx"))
583 /* we have .idx. Is it a file we can map? */
584 strcpy(path + len, de->d_name);
585 p = add_packed_git(path, len + namelen, local);
588 p->next = packed_git;
594 void prepare_packed_git(void)
596 static int run_once = 0;
597 struct alternate_object_database *alt;
601 prepare_packed_git_one(get_object_directory(), 1);
603 for (alt = alt_odb_list; alt; alt = alt->next) {
605 prepare_packed_git_one(alt->base, 0);
611 int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
614 unsigned char real_sha1[20];
618 SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
619 SHA1_Update(&c, map, size);
620 SHA1_Final(real_sha1, &c);
621 return memcmp(sha1, real_sha1, 20) ? -1 : 0;
624 static void *map_sha1_file_internal(const unsigned char *sha1,
630 char *filename = find_sha1_file(sha1, &st);
636 fd = open(filename, O_RDONLY | sha1_file_open_flag);
638 /* See if it works without O_NOATIME */
639 switch (sha1_file_open_flag) {
641 fd = open(filename, O_RDONLY);
649 /* If it failed once, it will probably fail again.
650 * Stop using O_NOATIME
652 sha1_file_open_flag = 0;
654 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
656 if (map == MAP_FAILED)
662 int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size)
664 /* Get the data stream */
665 memset(stream, 0, sizeof(*stream));
666 stream->next_in = map;
667 stream->avail_in = mapsize;
668 stream->next_out = buffer;
669 stream->avail_out = size;
672 return inflate(stream, 0);
675 static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
677 int bytes = strlen(buffer) + 1;
678 unsigned char *buf = xmalloc(1+size);
680 memcpy(buf, buffer + bytes, stream->total_out - bytes);
681 bytes = stream->total_out - bytes;
683 stream->next_out = buf + bytes;
684 stream->avail_out = size - bytes;
685 while (inflate(stream, Z_FINISH) == Z_OK)
694 * We used to just use "sscanf()", but that's actually way
695 * too permissive for what we want to check. So do an anal
696 * object header parse by hand.
698 int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
704 * The type can be at most ten bytes (including the
705 * terminating '\0' that we add), and is followed by
720 * The length must follow immediately, and be in canonical
721 * decimal format (ie "010" is not valid).
728 unsigned long c = *hdr - '0';
732 size = size * 10 + c;
738 * The length must be followed by a zero byte
740 return *hdr ? -1 : 0;
743 void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
749 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
750 if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
753 return unpack_sha1_rest(&stream, hdr, *size);
756 /* forward declaration for a mutually recursive function */
757 static int packed_object_info(struct pack_entry *entry,
758 char *type, unsigned long *sizep);
760 static int packed_delta_info(unsigned char *base_sha1,
761 unsigned long delta_size,
764 unsigned long *sizep,
765 struct packed_git *p)
767 struct pack_entry base_ent;
770 die("truncated pack file");
772 /* The base entry _must_ be in the same pack */
773 if (!find_pack_entry_one(base_sha1, &base_ent, p))
774 die("failed to find delta-pack base object %s",
775 sha1_to_hex(base_sha1));
777 /* We choose to only get the type of the base object and
778 * ignore potentially corrupt pack file that expects the delta
779 * based on a base with a wrong size. This saves tons of
783 if (packed_object_info(&base_ent, type, NULL))
784 die("cannot get info for delta-pack base");
787 const unsigned char *data;
788 unsigned char delta_head[64];
789 unsigned long result_size;
793 memset(&stream, 0, sizeof(stream));
795 data = stream.next_in = base_sha1 + 20;
796 stream.avail_in = left - 20;
797 stream.next_out = delta_head;
798 stream.avail_out = sizeof(delta_head);
800 inflateInit(&stream);
801 st = inflate(&stream, Z_FINISH);
803 if ((st != Z_STREAM_END) &&
804 stream.total_out != sizeof(delta_head))
805 die("delta data unpack-initial failed");
807 /* Examine the initial part of the delta to figure out
812 /* ignore base size */
813 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
815 /* Read the result size */
816 result_size = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
817 *sizep = result_size;
822 static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset,
823 enum object_type *type, unsigned long *sizep)
826 unsigned char *pack, c;
829 if (offset >= p->pack_size)
830 die("object offset outside of pack file");
832 pack = p->pack_base + offset;
835 *type = (c >> 4) & 7;
839 if (offset >= p->pack_size)
840 die("object offset outside of pack file");
843 size += (c & 0x7f) << shift;
850 int check_reuse_pack_delta(struct packed_git *p, unsigned long offset,
851 unsigned char *base, unsigned long *sizep,
852 enum object_type *kindp)
859 ptr = unpack_object_header(p, ptr, kindp, sizep);
860 if (*kindp != OBJ_DELTA)
862 memcpy(base, p->pack_base + ptr, 20);
869 void packed_object_info_detail(struct pack_entry *e,
872 unsigned long *store_size,
873 unsigned int *delta_chain_length,
874 unsigned char *base_sha1)
876 struct packed_git *p = e->p;
877 unsigned long offset, left;
879 enum object_type kind;
881 offset = unpack_object_header(p, e->offset, &kind, size);
882 pack = p->pack_base + offset;
883 left = p->pack_size - offset;
884 if (kind != OBJ_DELTA)
885 *delta_chain_length = 0;
887 unsigned int chain_length = 0;
888 memcpy(base_sha1, pack, 20);
890 struct pack_entry base_ent;
893 find_pack_entry_one(pack, &base_ent, p);
894 offset = unpack_object_header(p, base_ent.offset,
896 pack = p->pack_base + offset;
898 } while (kind == OBJ_DELTA);
899 *delta_chain_length = chain_length;
903 strcpy(type, commit_type);
906 strcpy(type, tree_type);
909 strcpy(type, blob_type);
912 strcpy(type, tag_type);
915 die("corrupted pack file %s containing object of kind %d",
918 *store_size = 0; /* notyet */
921 static int packed_object_info(struct pack_entry *entry,
922 char *type, unsigned long *sizep)
924 struct packed_git *p = entry->p;
925 unsigned long offset, size, left;
927 enum object_type kind;
930 if (use_packed_git(p))
931 die("cannot map packed file");
933 offset = unpack_object_header(p, entry->offset, &kind, &size);
934 pack = p->pack_base + offset;
935 left = p->pack_size - offset;
939 retval = packed_delta_info(pack, size, left, type, sizep, p);
943 strcpy(type, commit_type);
946 strcpy(type, tree_type);
949 strcpy(type, blob_type);
952 strcpy(type, tag_type);
955 die("corrupted pack file %s containing object of kind %d",
964 /* forward declaration for a mutually recursive function */
965 static void *unpack_entry(struct pack_entry *, char *, unsigned long *);
967 static void *unpack_delta_entry(unsigned char *base_sha1,
968 unsigned long delta_size,
971 unsigned long *sizep,
972 struct packed_git *p)
974 struct pack_entry base_ent;
975 void *data, *delta_data, *result, *base;
976 unsigned long data_size, result_size, base_size;
981 die("truncated pack file");
983 /* The base entry _must_ be in the same pack */
984 if (!find_pack_entry_one(base_sha1, &base_ent, p))
985 die("failed to find delta-pack base object %s",
986 sha1_to_hex(base_sha1));
987 base = unpack_entry_gently(&base_ent, type, &base_size);
989 die("failed to read delta-pack base object %s",
990 sha1_to_hex(base_sha1));
992 data = base_sha1 + 20;
993 data_size = left - 20;
994 delta_data = xmalloc(delta_size);
996 memset(&stream, 0, sizeof(stream));
998 stream.next_in = data;
999 stream.avail_in = data_size;
1000 stream.next_out = delta_data;
1001 stream.avail_out = delta_size;
1003 inflateInit(&stream);
1004 st = inflate(&stream, Z_FINISH);
1005 inflateEnd(&stream);
1006 if ((st != Z_STREAM_END) || stream.total_out != delta_size)
1007 die("delta data unpack failed");
1009 result = patch_delta(base, base_size,
1010 delta_data, delta_size,
1013 die("failed to apply delta");
1016 *sizep = result_size;
1020 static void *unpack_non_delta_entry(unsigned char *data,
1026 unsigned char *buffer;
1028 buffer = xmalloc(size + 1);
1030 memset(&stream, 0, sizeof(stream));
1031 stream.next_in = data;
1032 stream.avail_in = left;
1033 stream.next_out = buffer;
1034 stream.avail_out = size;
1036 inflateInit(&stream);
1037 st = inflate(&stream, Z_FINISH);
1038 inflateEnd(&stream);
1039 if ((st != Z_STREAM_END) || stream.total_out != size) {
1047 static void *unpack_entry(struct pack_entry *entry,
1048 char *type, unsigned long *sizep)
1050 struct packed_git *p = entry->p;
1053 if (use_packed_git(p))
1054 die("cannot map packed file");
1055 retval = unpack_entry_gently(entry, type, sizep);
1056 unuse_packed_git(p);
1058 die("corrupted pack file %s", p->pack_name);
1062 /* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
1063 void *unpack_entry_gently(struct pack_entry *entry,
1064 char *type, unsigned long *sizep)
1066 struct packed_git *p = entry->p;
1067 unsigned long offset, size, left;
1068 unsigned char *pack;
1069 enum object_type kind;
1072 offset = unpack_object_header(p, entry->offset, &kind, &size);
1073 pack = p->pack_base + offset;
1074 left = p->pack_size - offset;
1077 retval = unpack_delta_entry(pack, size, left, type, sizep, p);
1080 strcpy(type, commit_type);
1083 strcpy(type, tree_type);
1086 strcpy(type, blob_type);
1089 strcpy(type, tag_type);
1095 retval = unpack_non_delta_entry(pack, size, left);
1099 int num_packed_objects(const struct packed_git *p)
1101 /* See check_packed_git_idx() */
1102 return (p->index_size - 20 - 20 - 4*256) / 24;
1105 int nth_packed_object_sha1(const struct packed_git *p, int n,
1106 unsigned char* sha1)
1108 void *index = p->index_base + 256;
1109 if (n < 0 || num_packed_objects(p) <= n)
1111 memcpy(sha1, (index + 24 * n + 4), 20);
1115 int find_pack_entry_one(const unsigned char *sha1,
1116 struct pack_entry *e, struct packed_git *p)
1118 unsigned int *level1_ofs = p->index_base;
1119 int hi = ntohl(level1_ofs[*sha1]);
1120 int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
1121 void *index = p->index_base + 256;
1124 int mi = (lo + hi) / 2;
1125 int cmp = memcmp(index + 24 * mi + 4, sha1, 20);
1127 e->offset = ntohl(*((int*)(index + 24 * mi)));
1128 memcpy(e->sha1, sha1, 20);
1140 static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1142 struct packed_git *p;
1143 prepare_packed_git();
1145 for (p = packed_git; p; p = p->next) {
1146 if (find_pack_entry_one(sha1, e, p))
1152 struct packed_git *find_sha1_pack(const unsigned char *sha1,
1153 struct packed_git *packs)
1155 struct packed_git *p;
1156 struct pack_entry e;
1158 for (p = packs; p; p = p->next) {
1159 if (find_pack_entry_one(sha1, &e, p))
1166 int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
1169 unsigned long mapsize, size;
1174 map = map_sha1_file_internal(sha1, &mapsize);
1176 struct pack_entry e;
1178 if (!find_pack_entry(sha1, &e))
1179 return error("unable to find %s", sha1_to_hex(sha1));
1180 return packed_object_info(&e, type, sizep);
1182 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1183 status = error("unable to unpack %s header",
1185 if (parse_sha1_header(hdr, type, &size) < 0)
1186 status = error("unable to parse %s header", sha1_to_hex(sha1));
1192 inflateEnd(&stream);
1193 munmap(map, mapsize);
1197 static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
1199 struct pack_entry e;
1201 if (!find_pack_entry(sha1, &e)) {
1202 error("cannot read sha1_file for %s", sha1_to_hex(sha1));
1205 return unpack_entry(&e, type, size);
1208 void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
1210 unsigned long mapsize;
1212 struct pack_entry e;
1214 if (find_pack_entry(sha1, &e))
1215 return read_packed_sha1(sha1, type, size);
1216 map = map_sha1_file_internal(sha1, &mapsize);
1218 buf = unpack_sha1_file(map, mapsize, type, size);
1219 munmap(map, mapsize);
1225 void *read_object_with_reference(const unsigned char *sha1,
1226 const char *required_type,
1227 unsigned long *size,
1228 unsigned char *actual_sha1_return)
1232 unsigned long isize;
1233 unsigned char actual_sha1[20];
1235 memcpy(actual_sha1, sha1, 20);
1237 int ref_length = -1;
1238 const char *ref_type = NULL;
1240 buffer = read_sha1_file(actual_sha1, type, &isize);
1243 if (!strcmp(type, required_type)) {
1245 if (actual_sha1_return)
1246 memcpy(actual_sha1_return, actual_sha1, 20);
1249 /* Handle references */
1250 else if (!strcmp(type, commit_type))
1252 else if (!strcmp(type, tag_type))
1253 ref_type = "object ";
1258 ref_length = strlen(ref_type);
1260 if (memcmp(buffer, ref_type, ref_length) ||
1261 get_sha1_hex(buffer + ref_length, actual_sha1)) {
1266 /* Now we have the ID of the referred-to object in
1267 * actual_sha1. Check again. */
1271 char *write_sha1_file_prepare(void *buf,
1274 unsigned char *sha1,
1280 /* Generate the header */
1281 *hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1;
1285 SHA1_Update(&c, hdr, *hdrlen);
1286 SHA1_Update(&c, buf, len);
1287 SHA1_Final(sha1, &c);
1289 return sha1_file_name(sha1);
1293 * Link the tempfile to the final place, possibly creating the
1294 * last directory level as you do so.
1296 * Returns the errno on failure, 0 on success.
1298 static int link_temp_to_file(const char *tmpfile, char *filename)
1302 if (!link(tmpfile, filename))
1306 * Try to mkdir the last path component if that failed
1309 * Re-try the "link()" regardless of whether the mkdir
1310 * succeeds, since a race might mean that somebody
1314 if (ret == ENOENT) {
1315 char *dir = strrchr(filename, '/');
1318 mkdir(filename, 0777);
1319 if (adjust_shared_perm(filename))
1322 if (!link(tmpfile, filename))
1331 * Move the just written object into its final resting place
1333 int move_temp_to_file(const char *tmpfile, char *filename)
1335 int ret = link_temp_to_file(tmpfile, filename);
1338 * Coda hack - coda doesn't like cross-directory links,
1339 * so we fall back to a rename, which will mean that it
1340 * won't be able to check collisions, but that's not a
1343 * The same holds for FAT formatted media.
1345 * When this succeeds, we just return 0. We have nothing
1348 if (ret && ret != EEXIST) {
1349 if (!rename(tmpfile, filename))
1355 if (ret != EEXIST) {
1356 fprintf(stderr, "unable to write sha1 filename %s: %s\n", filename, strerror(ret));
1359 /* FIXME!!! Collision check here ? */
1365 int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
1368 unsigned char *compressed;
1370 unsigned char sha1[20];
1372 static char tmpfile[PATH_MAX];
1373 unsigned char hdr[50];
1376 /* Normally if we have it in the pack then we do not bother writing
1377 * it out into .git/objects/??/?{38} file.
1379 filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1381 memcpy(returnsha1, sha1, 20);
1382 if (has_sha1_file(sha1))
1384 fd = open(filename, O_RDONLY);
1387 * FIXME!!! We might do collision checking here, but we'd
1388 * need to uncompress the old file and check it. Later.
1394 if (errno != ENOENT) {
1395 fprintf(stderr, "sha1 file %s: %s\n", filename, strerror(errno));
1399 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
1401 fd = mkstemp(tmpfile);
1403 fprintf(stderr, "unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
1408 memset(&stream, 0, sizeof(stream));
1409 deflateInit(&stream, Z_BEST_COMPRESSION);
1410 size = deflateBound(&stream, len+hdrlen);
1411 compressed = xmalloc(size);
1414 stream.next_out = compressed;
1415 stream.avail_out = size;
1417 /* First header.. */
1418 stream.next_in = hdr;
1419 stream.avail_in = hdrlen;
1420 while (deflate(&stream, 0) == Z_OK)
1423 /* Then the data itself.. */
1424 stream.next_in = buf;
1425 stream.avail_in = len;
1426 while (deflate(&stream, Z_FINISH) == Z_OK)
1428 deflateEnd(&stream);
1429 size = stream.total_out;
1431 if (write(fd, compressed, size) != size)
1432 die("unable to write file");
1437 return move_temp_to_file(tmpfile, filename);
1440 int write_sha1_to_fd(int fd, const unsigned char *sha1)
1443 unsigned long objsize;
1445 void *map = map_sha1_file_internal(sha1, &objsize);
1447 void *temp_obj = NULL;
1451 unsigned char *unpacked;
1456 // need to unpack and recompress it by itself
1457 unpacked = read_packed_sha1(sha1, type, &len);
1459 hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
1462 memset(&stream, 0, sizeof(stream));
1463 deflateInit(&stream, Z_BEST_COMPRESSION);
1464 size = deflateBound(&stream, len + hdrlen);
1465 temp_obj = buf = xmalloc(size);
1468 stream.next_out = buf;
1469 stream.avail_out = size;
1471 /* First header.. */
1472 stream.next_in = (void *)hdr;
1473 stream.avail_in = hdrlen;
1474 while (deflate(&stream, 0) == Z_OK)
1477 /* Then the data itself.. */
1478 stream.next_in = unpacked;
1479 stream.avail_in = len;
1480 while (deflate(&stream, Z_FINISH) == Z_OK)
1482 deflateEnd(&stream);
1485 objsize = stream.total_out;
1489 size = write(fd, buf + posn, objsize - posn);
1492 fprintf(stderr, "write closed\n");
1499 } while (posn < objsize);
1502 munmap(map, objsize);
1509 int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
1510 size_t bufsize, size_t *bufposn)
1512 char tmpfile[PATH_MAX];
1515 unsigned char real_sha1[20];
1516 unsigned char discard[4096];
1520 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
1522 local = mkstemp(tmpfile);
1524 return error("Couldn't open %s for %s",
1525 tmpfile, sha1_to_hex(sha1));
1527 memset(&stream, 0, sizeof(stream));
1529 inflateInit(&stream);
1536 stream.avail_in = *bufposn;
1537 stream.next_in = (unsigned char *) buffer;
1539 stream.next_out = discard;
1540 stream.avail_out = sizeof(discard);
1541 ret = inflate(&stream, Z_SYNC_FLUSH);
1542 SHA1_Update(&c, discard, sizeof(discard) -
1544 } while (stream.avail_in && ret == Z_OK);
1545 write(local, buffer, *bufposn - stream.avail_in);
1546 memmove(buffer, buffer + *bufposn - stream.avail_in,
1548 *bufposn = stream.avail_in;
1552 size = read(fd, buffer + *bufposn, bufsize - *bufposn);
1557 return error("Connection closed?");
1558 perror("Reading from connection");
1563 inflateEnd(&stream);
1566 SHA1_Final(real_sha1, &c);
1567 if (ret != Z_STREAM_END) {
1569 return error("File %s corrupted", sha1_to_hex(sha1));
1571 if (memcmp(sha1, real_sha1, 20)) {
1573 return error("File %s has bad hash", sha1_to_hex(sha1));
1576 return move_temp_to_file(tmpfile, sha1_file_name(sha1));
1579 int has_pack_index(const unsigned char *sha1)
1582 if (stat(sha1_pack_index_name(sha1), &st))
1587 int has_pack_file(const unsigned char *sha1)
1590 if (stat(sha1_pack_name(sha1), &st))
1595 int has_sha1_pack(const unsigned char *sha1)
1597 struct pack_entry e;
1598 return find_pack_entry(sha1, &e);
1601 int has_sha1_file(const unsigned char *sha1)
1604 struct pack_entry e;
1606 if (find_pack_entry(sha1, &e))
1608 return find_sha1_file(sha1, &st) ? 1 : 0;
1611 int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
1613 unsigned long size = 4096;
1614 char *buf = malloc(size);
1616 unsigned long off = 0;
1617 unsigned char hdr[50];
1620 iret = read(fd, buf + off, size - off);
1625 buf = realloc(buf, size);
1636 ret = write_sha1_file(buf, off, type, sha1);
1638 write_sha1_file_prepare(buf, off, type, sha1, hdr, &hdrlen);
1645 int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
1647 unsigned long size = st->st_size;
1650 unsigned char hdr[50];
1655 buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
1657 if (buf == MAP_FAILED)
1663 ret = write_sha1_file(buf, size, type, sha1);
1665 write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
1673 int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
1678 switch (st->st_mode & S_IFMT) {
1680 fd = open(path, O_RDONLY);
1682 return error("open(\"%s\"): %s", path,
1684 if (index_fd(sha1, fd, st, write_object, NULL) < 0)
1685 return error("%s: failed to insert into database",
1689 target = xmalloc(st->st_size+1);
1690 if (readlink(path, target, st->st_size+1) != st->st_size) {
1691 char *errstr = strerror(errno);
1693 return error("readlink(\"%s\"): %s", path,
1696 if (!write_object) {
1697 unsigned char hdr[50];
1699 write_sha1_file_prepare(target, st->st_size, blob_type,
1700 sha1, hdr, &hdrlen);
1701 } else if (write_sha1_file(target, st->st_size, blob_type, sha1))
1702 return error("%s: failed to insert into database",
1707 return error("%s: unsupported file type", path);