implement Crc; include "crc.m"; init(poly : int, reg : int) : ref CRCstate{ if (poly == 0) poly = int 16redb88320; tab := array[256] of int; for(i := 0; i < 256; i++){ crc := i; for(j := 0; j < 8; j++){ c := crc & 1; crc = (crc >> 1) & 16r7fffffff; if(c) crc ^= poly; } tab[i] = crc; } crcs := ref CRCstate; crcs.crc = 0; crcs.crctab = tab; crcs.reg = reg; return crcs;} crc(crcs : ref CRCstate, buf : array of byte, nb : int) : int{ n := nb; if (n > len buf) n = len buf; crc := crcs.crc; tab := crcs.crctab; crc ^= crcs.reg; for (i := 0; i < n; i++) crc = tab[int(byte crc ^ buf[i])] ^ ((crc >> 8) & 16r00ffffff); crc ^= crcs.reg; crcs.crc = crc; return crc;} reset(crcs : ref CRCstate){ crcs.crc = 0;}
implement Crc;
include "crc.m";
init(poly : int, reg : int) : ref CRCstate
{
if (poly == 0)
poly = int 16redb88320;
tab := array[256] of int;
for(i := 0; i < 256; i++){
crc := i;
for(j := 0; j < 8; j++){
c := crc & 1;
crc = (crc >> 1) & 16r7fffffff;
if(c)
crc ^= poly;
}
tab[i] = crc;
}
crcs := ref CRCstate;
crcs.crc = 0;
crcs.crctab = tab;
crcs.reg = reg;
return crcs;
}
crc(crcs : ref CRCstate, buf : array of byte, nb : int) : int
{
n := nb;
if (n > len buf)
n = len buf;
crc := crcs.crc;
tab := crcs.crctab;
crc ^= crcs.reg;
for (i := 0; i < n; i++)
crc = tab[int(byte crc ^ buf[i])] ^ ((crc >> 8) & 16r00ffffff);
crc ^= crcs.reg;
crcs.crc = crc;
return crc;
}
reset(crcs : ref CRCstate)
{
crcs.crc = 0;
}