xref: /netbsd-src/common/lib/libc/arch/m68k/string/strncpy.S (revision 18ec38ea7c8331c5bc28d877de4a5b1391957c39)
1*18ec38eaSchs/*	$NetBSD: strncpy.S,v 1.5 2013/09/07 19:06:29 chs Exp $	*/
237c9f0a6Schristos
337c9f0a6Schristos/*-
437c9f0a6Schristos * Copyright (c) 1990 The Regents of the University of California.
537c9f0a6Schristos * All rights reserved.
637c9f0a6Schristos *
737c9f0a6Schristos * This code is derived from software contributed to Berkeley by
837c9f0a6Schristos * the Systems Programming Group of the University of Utah Computer
937c9f0a6Schristos * Science Department.
1037c9f0a6Schristos *
1137c9f0a6Schristos * Redistribution and use in source and binary forms, with or without
1237c9f0a6Schristos * modification, are permitted provided that the following conditions
1337c9f0a6Schristos * are met:
1437c9f0a6Schristos * 1. Redistributions of source code must retain the above copyright
1537c9f0a6Schristos *    notice, this list of conditions and the following disclaimer.
1637c9f0a6Schristos * 2. Redistributions in binary form must reproduce the above copyright
1737c9f0a6Schristos *    notice, this list of conditions and the following disclaimer in the
1837c9f0a6Schristos *    documentation and/or other materials provided with the distribution.
1937c9f0a6Schristos * 3. Neither the name of the University nor the names of its contributors
2037c9f0a6Schristos *    may be used to endorse or promote products derived from this software
2137c9f0a6Schristos *    without specific prior written permission.
2237c9f0a6Schristos *
2337c9f0a6Schristos * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2437c9f0a6Schristos * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2537c9f0a6Schristos * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2637c9f0a6Schristos * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2737c9f0a6Schristos * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2837c9f0a6Schristos * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2937c9f0a6Schristos * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
3037c9f0a6Schristos * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
3137c9f0a6Schristos * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
3237c9f0a6Schristos * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3337c9f0a6Schristos * SUCH DAMAGE.
3437c9f0a6Schristos */
3537c9f0a6Schristos
3637c9f0a6Schristos#include <machine/asm.h>
3737c9f0a6Schristos
3837c9f0a6Schristos#if defined(LIBC_SCCS) && !defined(lint)
3937c9f0a6Schristos#if 0
4037c9f0a6Schristos	RCSID("from: @(#)strncpy.s	5.1 (Berkeley) 5/12/90")
4137c9f0a6Schristos#else
42*18ec38eaSchs	RCSID("$NetBSD: strncpy.S,v 1.5 2013/09/07 19:06:29 chs Exp $")
4337c9f0a6Schristos#endif
4437c9f0a6Schristos#endif /* LIBC_SCCS and not lint */
4537c9f0a6Schristos
4637c9f0a6SchristosENTRY(strncpy)
4707a0a325Smatt	movl	4(%sp),%d0		| return value is toaddr
4807a0a325Smatt	movl	12(%sp),%d1		| count
49*18ec38eaSchs	jeq	.Lscdone		| nothing to do
5007a0a325Smatt	movl	8(%sp),%a0		| a0 = fromaddr
5137c9f0a6Schristos	movl	%d0,%a1			| a1 = toaddr
5237c9f0a6Schristos	subql	#1,%d1
53*18ec38eaSchs.Lscloop:
5407a0a325Smatt	movb	(%a0)+,(%a1)+		| copy a byte
551d398a17Smatt#ifndef __mcoldfire__
56*18ec38eaSchs	dbeq	%d1,.Lscloop		| loop through low word of d1
571d398a17Smatt#endif
58*18ec38eaSchs	jeq	.Lscpadding		| copied null, padding if necessary
591d398a17Smatt#ifndef __mcoldfire__
6037c9f0a6Schristos	clrw	%d1			| clear low word of d1
611d398a17Smatt#endif
6237c9f0a6Schristos	subql	#1,%d1			| adjust count for long copies
63*18ec38eaSchs	jcc	.Lscloop		| more room, keep going
64*18ec38eaSchs.Lscdone:
6537c9f0a6Schristos#ifdef __SVR4_ABI__
6637c9f0a6Schristos	moveal	%d0,%a0
6737c9f0a6Schristos#endif
6837c9f0a6Schristos	rts
6937c9f0a6Schristos
70*18ec38eaSchs.Lscploop:
7107a0a325Smatt	clrb	(%a1)+			| clear a byte
721d398a17Smatt#ifndef __mcoldfire__
73*18ec38eaSchs	dbra	%d1,.Lscploop		| keep going
7437c9f0a6Schristos	clrw	%d1
751d398a17Smatt#endif
76*18ec38eaSchs.Lscpadding:
7737c9f0a6Schristos	subql	#1,%d1
78*18ec38eaSchs	jcc	.Lscploop
79*18ec38eaSchs	jra	.Lscdone
8065726debSmattEND(strncpy)
81