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/*	$OpenBSD: strncpy.S,v 1.3 2003/06/02 23:28:08 millert Exp $	*/

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
	.text
	/*.asciz "from: @(#)strncpy.s	5.1 (Berkeley) 5/12/90"*/
	.asciz "$OpenBSD: strncpy.S,v 1.3 2003/06/02 23:28:08 millert Exp $"
#endif /* LIBC_SCCS and not lint */

#include "DEFS.h"

ENTRY(strncpy)
	movl	sp@(4),d0		| return value is toaddr
	movl	sp@(12),d1		| count
	beq	scdone			| nothing to do
	movl	sp@(8),a0		| a0 = fromaddr
	movl	d0,a1			| a1 = toaddr
scloop:
	movb	a0@+,a1@+		| copy a byte
	beq	scploop			| copied null, go pad if necessary
	subql	#1,d1			| adjust count
	bne	scloop			| more room, keep going
scdone:
	rts
scploop:
	subql	#1,d1			| adjust count
	beq	scdone			| no more room, all done
	clrb	a1@+			| clear a byte
	jra	scploop			| keep going