1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
|
/* Copyright (C) 2000 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* 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 */
|
