X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;ds=sidebyside;f=sha1_file.c;h=18dece46b1e248a4e52e9ead3bf172ed6ab78236;hb=498fe00201401b766a200cf423a8ec42b5d5643e;hp=e666aec502f1aaadac62c72c152beeab15a8bd8e;hpb=5cd060b56c3d0b9f2340377d73dfe1abbcbe8a20;p=git.git diff --git a/sha1_file.c b/sha1_file.c index e666aec50..18dece46b 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -22,7 +22,7 @@ #endif #endif -const unsigned char null_sha1[20] = { 0, }; +const unsigned char null_sha1[20]; static unsigned int sha1_file_open_flag = O_NOATIME; @@ -590,7 +590,7 @@ static void prepare_packed_git_one(char *objdir, int local) int namelen = strlen(de->d_name); struct packed_git *p; - if (strcmp(de->d_name + namelen - 4, ".idx")) + if (!has_extension(de->d_name, ".idx")) continue; /* we have .idx. Is it a file we can map? */ @@ -646,8 +646,7 @@ int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long siz return memcmp(sha1, real_sha1, 20) ? -1 : 0; } -static void *map_sha1_file_internal(const unsigned char *sha1, - unsigned long *size) +void *map_sha1_file(const unsigned char *sha1, unsigned long *size) { struct stat st; void *map; @@ -684,26 +683,84 @@ static void *map_sha1_file_internal(const unsigned char *sha1, return map; } -static int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size) +int legacy_loose_object(unsigned char *map) { + unsigned int word; + + /* + * Is it a zlib-compressed buffer? If so, the first byte + * must be 0x78 (15-bit window size, deflated), and the + * first 16-bit word is evenly divisible by 31 + */ + word = (map[0] << 8) + map[1]; + if (map[0] == 0x78 && !(word % 31)) + return 1; + else + return 0; +} + +static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz) +{ + unsigned char c; + unsigned int bits; + unsigned long size; + static const char *typename[8] = { + NULL, /* OBJ_EXT */ + "commit", "tree", "blob", "tag", + NULL, NULL, NULL + }; + const char *type; + /* Get the data stream */ memset(stream, 0, sizeof(*stream)); stream->next_in = map; stream->avail_in = mapsize; stream->next_out = buffer; - stream->avail_out = size; + stream->avail_out = bufsiz; + + if (legacy_loose_object(map)) { + inflateInit(stream); + return inflate(stream, 0); + } + + c = *map++; + mapsize--; + type = typename[(c >> 4) & 7]; + if (!type) + return -1; + bits = 4; + size = c & 0xf; + while ((c & 0x80)) { + if (bits >= 8*sizeof(long)) + return -1; + c = *map++; + size += (c & 0x7f) << bits; + bits += 7; + mapsize--; + } + + /* Set up the stream for the rest.. */ + stream->next_in = map; + stream->avail_in = mapsize; inflateInit(stream); - return inflate(stream, 0); + + /* And generate the fake traditional header */ + stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu", type, size); + return 0; } static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size) { int bytes = strlen(buffer) + 1; unsigned char *buf = xmalloc(1+size); + unsigned long n; - memcpy(buf, (char *) buffer + bytes, stream->total_out - bytes); - bytes = stream->total_out - bytes; + n = stream->total_out - bytes; + if (n > size) + n = size; + memcpy(buf, (char *) buffer + bytes, n); + bytes = n; if (bytes < size) { stream->next_out = buf + bytes; stream->avail_out = size - bytes; @@ -1198,7 +1255,7 @@ int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep z_stream stream; char hdr[128]; - map = map_sha1_file_internal(sha1, &mapsize); + map = map_sha1_file(sha1, &mapsize); if (!map) { struct pack_entry e; @@ -1243,7 +1300,7 @@ void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size if (find_pack_entry(sha1, &e)) return read_packed_sha1(sha1, type, size); - map = map_sha1_file_internal(sha1, &mapsize); + map = map_sha1_file(sha1, &mapsize); if (map) { buf = unpack_sha1_file(map, mapsize, type, size); munmap(map, mapsize); @@ -1412,6 +1469,49 @@ static int write_buffer(int fd, const void *buf, size_t len) return 0; } +static int write_binary_header(unsigned char *hdr, enum object_type type, unsigned long len) +{ + int hdr_len; + unsigned char c; + + c = (type << 4) | (len & 15); + len >>= 4; + hdr_len = 1; + while (len) { + *hdr++ = c | 0x80; + hdr_len++; + c = (len & 0x7f); + len >>= 7; + } + *hdr = c; + return hdr_len; +} + +static void setup_object_header(z_stream *stream, const char *type, unsigned long len) +{ + int obj_type, hdr; + + if (use_legacy_headers) { + while (deflate(stream, 0) == Z_OK) + /* nothing */; + return; + } + if (!strcmp(type, blob_type)) + obj_type = OBJ_BLOB; + else if (!strcmp(type, tree_type)) + obj_type = OBJ_TREE; + else if (!strcmp(type, commit_type)) + obj_type = OBJ_COMMIT; + else if (!strcmp(type, tag_type)) + obj_type = OBJ_TAG; + else + die("trying to generate bogus object of type '%s'", type); + hdr = write_binary_header(stream->next_out, obj_type, len); + stream->total_out = hdr; + stream->next_out += hdr; + stream->avail_out -= hdr; +} + int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1) { int size; @@ -1457,7 +1557,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha /* Set it up */ memset(&stream, 0, sizeof(stream)); deflateInit(&stream, zlib_compression_level); - size = deflateBound(&stream, len+hdrlen); + size = 8 + deflateBound(&stream, len+hdrlen); compressed = xmalloc(size); /* Compress it */ @@ -1467,8 +1567,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha /* First header.. */ stream.next_in = hdr; stream.avail_in = hdrlen; - while (deflate(&stream, 0) == Z_OK) - /* nothing */; + setup_object_header(&stream, type, len); /* Then the data itself.. */ stream.next_in = buf; @@ -1539,7 +1638,7 @@ int write_sha1_to_fd(int fd, const unsigned char *sha1) { int retval; unsigned long objsize; - void *buf = map_sha1_file_internal(sha1, &objsize); + void *buf = map_sha1_file(sha1, &objsize); if (buf) { retval = write_buffer(fd, buf, objsize);