rs_block_sig_t *rs_signature_add_block(rs_signature_t *sig, rs_weak_sum_t weak_sum, rs_strong_sum_t *strong_sum)
{
rs_signature_check(sig);
/* If block_sigs is full, allocate more space. */
if (sig->count == sig->size) {
sig->size = sig->size ? sig->size * 2 : 16;
sig->block_sigs = rs_realloc(sig->block_sigs, sig->size * rs_block_sig_size(sig), "signature->block_sigs");
}
rs_block_sig_t *b = rs_block_sig_ptr(sig, sig->count++);
rs_block_sig_init(b, weak_sum, strong_sum, sig->strong_sum_len);
return b;
}
rs_result rs_signature_init(rs_signature_t *sig, int magic, int block_len,
int strong_len, rs_long_t sig_fsize)
{
int max_strong_len;
/* Check and set default arguments. */
magic = magic ? magic : RS_BLAKE2_SIG_MAGIC;
switch (magic) {
case RS_BLAKE2_SIG_MAGIC:
max_strong_len = RS_BLAKE2_SUM_LENGTH;
break;
case RS_MD4_SIG_MAGIC:
max_strong_len = RS_MD4_SUM_LENGTH;
break;
default:
rs_error("invalid magic %#x", magic);
return RS_BAD_MAGIC;
}
strong_len = strong_len ? strong_len : max_strong_len;
if (strong_len < 1 || max_strong_len < strong_len) {
rs_error("invalid strong_sum_len %d for magic %#x", strong_len, magic);
return RS_PARAM_ERROR;
}
/* Set attributes from args. */
sig->magic = magic;
sig->block_len = block_len;
sig->strong_sum_len = strong_len;
sig->count = 0;
/* Calculate the number of blocks if we have the signature file size. */
/* Magic+header is 12 bytes, each block thereafter is 4 bytes
weak_sum+strong_sum_len bytes */
sig->size = (int)(sig_fsize ? (sig_fsize - 12) / (4 + strong_len) : 0);
if (sig->size)
sig->block_sigs =
rs_alloc(sig->size * rs_block_sig_size(sig),
"signature->block_sigs");
else
sig->block_sigs = NULL;
sig->hashtable = NULL;
#ifndef HASHTABLE_NSTATS
sig->calc_strong_count = 0;
#endif
rs_signature_check(sig);
return RS_DONE;
}
/* Get the index of a block from a block_sig_t pointer. */
static inline int rs_block_sig_idx(const rs_signature_t *sig, rs_block_sig_t *block_sig)
{
return ((char *)block_sig - (char *)sig->block_sigs) / rs_block_sig_size(sig);
}
/* Get the pointer to the block_sig_t from a block index. */
static inline rs_block_sig_t *rs_block_sig_ptr(const rs_signature_t *sig, int block_idx)
{
return (rs_block_sig_t*)((char*)sig->block_sigs + block_idx * rs_block_sig_size(sig));
}
