MGMDB/MySQL/bmove.c

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2011-10-02 20:48:43 -05:00
/* Copyright (C) 2002 MySQL AB
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; version 2
of the License.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA */
/* File : bmove.c
Author : Richard A. O'Keefe.
Michael Widenius; ifdef MC68000
Updated: 23 April 1984
Defines: bmove()
bmove(dst, src, len) moves exactly "len" bytes from the source "src"
to the destination "dst". It does not check for NUL characters as
strncpy() and strnmov() do. Thus if your C compiler doesn't support
structure assignment, you can simulate it with
bmove(&to, &from, sizeof from);
The standard 4.2bsd routine for this purpose is bcopy. But as bcopy
has its first two arguments the other way around you may find this a
bit easier to get right.
No value is returned.
Note: the "b" routines are there to exploit certain VAX order codes,
but the MOVC3 instruction will only move 65535 characters. The asm
code is presented for your interest and amusement.
*/
#include <my_global.h>
#include "m_string.h"
#if !defined(HAVE_BMOVE) && !defined(bmove)
#if VaxAsm
void bmove(dst, src, len)
char *dst, *src;
uint len;
{
asm("movc3 12(ap),*8(ap),*4(ap)");
}
#else
#if defined(MC68000) && defined(DS90)
void bmove(dst, src, len)
char *dst,*src;
uint len; /* 0 <= len <= 65535 */
{
asm(" movl 12(a7),d0 ");
asm(" subql #1,d0 ");
asm(" blt .L5 ");
asm(" movl 4(a7),a1 ");
asm(" movl 8(a7),a0 ");
asm(".L4: movb (a0)+,(a1)+ ");
asm(" dbf d0,.L4 ");
asm(".L5: ");
}
#else
void bmove(dst, src, len)
register char *dst;
register const char *src;
register uint len;
{
while (len-- != 0) *dst++ = *src++;
}
#endif
#endif
#endif