diff options
Diffstat (limited to 'sha1_file.c')
| -rw-r--r-- | sha1_file.c | 132 |
1 files changed, 110 insertions, 22 deletions
diff --git a/sha1_file.c b/sha1_file.c index 8734d501f..43bc2ea0c 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -684,26 +684,74 @@ 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) +static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz) { + unsigned char c; + unsigned int word, 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; + + /* + * 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)) { + 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; @@ -1331,31 +1379,29 @@ char *write_sha1_file_prepare(void *buf, static int link_temp_to_file(const char *tmpfile, char *filename) { int ret; + char *dir; if (!link(tmpfile, filename)) return 0; /* - * Try to mkdir the last path component if that failed - * with an ENOENT. + * Try to mkdir the last path component if that failed. * * Re-try the "link()" regardless of whether the mkdir * succeeds, since a race might mean that somebody * else succeeded. */ ret = errno; - if (ret == ENOENT) { - char *dir = strrchr(filename, '/'); - if (dir) { - *dir = 0; - mkdir(filename, 0777); - if (adjust_shared_perm(filename)) - return -2; - *dir = '/'; - if (!link(tmpfile, filename)) - return 0; - ret = errno; - } + dir = strrchr(filename, '/'); + if (dir) { + *dir = 0; + mkdir(filename, 0777); + if (adjust_shared_perm(filename)) + return -2; + *dir = '/'; + if (!link(tmpfile, filename)) + return 0; + ret = errno; } return ret; } @@ -1414,6 +1460,49 @@ 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; @@ -1459,7 +1548,7 @@ 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 */ @@ -1469,8 +1558,7 @@ 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; |