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/* File : bzero.c
Author : Richard A. O'Keefe.
Michael Widenius; ifdef MC68000
Updated: 23 April 1984
Defines: bzero()
bzero(dst, len) moves "len" 0 bytes to "dst".
Thus to clear a disc buffer to 0s do bzero(buffer, BUFSIZ).
Note: the "b" routines are there to exploit certain VAX order codes,
The asm code is presented for your interest and amusement.
*/
#ifndef BSD_FUNCS
#include "strings.h"
#ifdef bzero
#undef bzero /* remove macro */
#endif
#if VaxAsm
static void _bzero64 _A((char *dst,int len));
void bzero(dst, len)
char *dst;
uint len;
{
while ((int) len >= 64*K)
{
_bzero64(dst, 64*K-1);
dst += 64*K-1;
len -= 64*K-1;
}
_bzero64(dst, len);
}
_bzero64(dst, len)
char *dst;
int len;
{
asm("movc5 $0,*4(ap),$0,8(ap),*4(ap)");
}
#else
#if defined(MC68000) && defined(DS90)
void bzero(dst, len)
char *dst;
uint len;
{
bfill(dst,len,0); /* This is very optimized ! */
} /* bzero */
#else
void bzero(dst, len)
register char *dst;
register uint len;
{
while (len-- != 0) *dst++ = 0;
} /* bzero */
#endif
#endif
#endif /* BSD_FUNCS */
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