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#ifndef LINT
static char sccsid[]="@(#) addbfcrc.c 2.2 88/01/29 17:04:31";
#endif /* LINT */
#include "options.h"
/*
addbfcrc() accepts a buffer address and a count and adds the CRC for
all bytes in the buffer to the global variable crccode using
CRC-16.
CRC computation algorithm originally from an article by David Schwaderer
in the April 1985 issue of PC Tech Journal.
Loop optimization done by J. Brian Waters.
I claim no copyright over the contents of this file.
-- Rahul Dhesi 1986/08/27
*/
extern unsigned int crccode;
extern unsigned crctab[];
void addbfcrc(buffer,count)
register char *buffer;
register int count;
{
register unsigned int localcrc;
localcrc = crccode;
for (; count--; )
localcrc = (localcrc>>8) ^ crctab[(localcrc ^ (*buffer++)) & 0x00ff];
crccode = localcrc;
}
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