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3.00c Win32

/* CRC16.C */

/* 16-bit CRC routines */

#include "smblib.h"

/****************************************************************************/
/* Updates 16-bit "rcrc" with character 'ch'                                */
/****************************************************************************/
void ucrc16(uchar ch, ushort *rcrc) {
    ushort i, cy;
    uchar nch=ch;
 
for (i=0; i<8; i++) {
    cy=*rcrc & 0x8000;
    *rcrc<<=1;
    if (nch & 0x80) *rcrc |= 1;
    nch<<=1;
    if (cy) *rcrc ^= 0x1021; }
}

/****************************************************************************/
/* Returns 16-crc of string (not counting terminating NULL)                 */
/****************************************************************************/
ushort crc16(char *str)
{
    int     i=0;
    ushort  crc=0;

ucrc16(0,&crc);
while(str[i])
    ucrc16(str[i++],&crc);
ucrc16(0,&crc);
ucrc16(0,&crc);
return(crc);
}

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