- unsigned char real_sha1[20];
- SHA_CTX c;
-
- SHA1_Init(&c);
- SHA1_Update(&c, map, size);
- SHA1_Final(real_sha1, &c);
- return memcmp(sha1, real_sha1, 20) ? -1 : 0;
-}
-
-void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
-{
- char *filename = sha1_file_name(sha1);
- int fd = open(filename, O_RDONLY);
- struct stat st;
- void *map;
-
- if (fd < 0) {
- perror(filename);
- return NULL;
- }
- if (fstat(fd, &st) < 0) {
- close(fd);
- return NULL;
- }
- map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
- close(fd);
- if (-1 == (int)(long)map)
- return NULL;
- *size = st.st_size;
- return map;
-}
-
-void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
-{
- int ret, bytes;
- z_stream stream;
- char buffer[8192];
- char *buf;
-
- /* Get the data stream */
- memset(&stream, 0, sizeof(stream));
- stream.next_in = map;
- stream.avail_in = mapsize;
- stream.next_out = buffer;
- stream.avail_out = sizeof(buffer);
-
- inflateInit(&stream);
- ret = inflate(&stream, 0);
- if (sscanf(buffer, "%10s %lu", type, size) != 2)
- return NULL;
-
- bytes = strlen(buffer) + 1;
- buf = malloc(*size);
- if (!buf)
- return NULL;
-
- memcpy(buf, buffer + bytes, stream.total_out - bytes);
- bytes = stream.total_out - bytes;
- if (bytes < *size && ret == Z_OK) {
- stream.next_out = buf + bytes;
- stream.avail_out = *size - bytes;
- while (inflate(&stream, Z_FINISH) == Z_OK)
- /* nothing */;
- }
- inflateEnd(&stream);
- return buf;
-}
-
-void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
-{
- unsigned long mapsize;
- void *map, *buf;
-
- map = map_sha1_file(sha1, &mapsize);
- if (map) {
- buf = unpack_sha1_file(map, mapsize, type, size);
- munmap(map, mapsize);
- return buf;
- }
- return NULL;
-}
-
-int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
-{
- int size;
- char *compressed;
- z_stream stream;
- unsigned char sha1[20];
- SHA_CTX c;
-
- /* Set it up */
- memset(&stream, 0, sizeof(stream));
- deflateInit(&stream, Z_BEST_COMPRESSION);
- size = deflateBound(&stream, len);
- compressed = malloc(size);
-
- /* Compress it */
- stream.next_in = buf;
- stream.avail_in = len;
- stream.next_out = compressed;
- stream.avail_out = size;
- while (deflate(&stream, Z_FINISH) == Z_OK)
- /* nothing */;
- deflateEnd(&stream);
- size = stream.total_out;
-
- /* Sha1.. */
- SHA1_Init(&c);
- SHA1_Update(&c, compressed, size);
- SHA1_Final(sha1, &c);
-
- if (write_sha1_buffer(sha1, compressed, size) < 0)
- return -1;
- if (returnsha1)
- memcpy(returnsha1, sha1, 20);
- return 0;
-}
-
-int write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size)
-{
- char *filename = sha1_file_name(sha1);
- int fd;
-
- fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
- if (fd < 0) {
- void *map;
-
- if (errno != EEXIST)
- return -1;
-#ifndef COLLISION_CHECK
- fd = open(filename, O_RDONLY);
- if (fd < 0)
- return -1;
- map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
- if (map == MAP_FAILED)
- return -1;
- if (memcmp(buf, map, size))
- return error("SHA1 collision detected!"
- " This is bad, bad, BAD!\a\n");