mirror of
https://github.com/servalproject/serval-dna.git
synced 2024-12-30 09:58:55 +00:00
27 lines
935 B
C
27 lines
935 B
C
/* Stuff common to all the general-purpose Reed-Solomon codecs
|
|
* Copyright 2004 Phil Karn, KA9Q
|
|
* May be used under the terms of the GNU Lesser General Public License (LGPL)
|
|
*/
|
|
|
|
/* Reed-Solomon codec control block */
|
|
struct rs {
|
|
int mm; /* Bits per symbol */
|
|
int nn; /* Symbols per block (= (1<<mm)-1) */
|
|
data_t *alpha_to; /* log lookup table */
|
|
data_t *index_of; /* Antilog lookup table */
|
|
data_t *genpoly; /* Generator polynomial */
|
|
int nroots; /* Number of generator roots = number of parity symbols */
|
|
int fcr; /* First consecutive root, index form */
|
|
int prim; /* Primitive element, index form */
|
|
int iprim; /* prim-th root of 1, index form */
|
|
int pad; /* Padding bytes in shortened block */
|
|
};
|
|
|
|
static inline int modnn(struct rs *rs,int x){
|
|
while (x >= rs->nn) {
|
|
x -= rs->nn;
|
|
x = (x >> rs->mm) + (x & rs->nn);
|
|
}
|
|
return x;
|
|
}
|