xref: /minix3/common/lib/libc/arch/m68k/string/strncpy.S (revision 84d9c625bfea59e274550651111ae9edfdc40fbd)
1*84d9c625SLionel Sambuc/*	$NetBSD: strncpy.S,v 1.5 2013/09/07 19:06:29 chs Exp $	*/
2b6cbf720SGianluca Guida
3b6cbf720SGianluca Guida/*-
4b6cbf720SGianluca Guida * Copyright (c) 1990 The Regents of the University of California.
5b6cbf720SGianluca Guida * All rights reserved.
6b6cbf720SGianluca Guida *
7b6cbf720SGianluca Guida * This code is derived from software contributed to Berkeley by
8b6cbf720SGianluca Guida * the Systems Programming Group of the University of Utah Computer
9b6cbf720SGianluca Guida * Science Department.
10b6cbf720SGianluca Guida *
11b6cbf720SGianluca Guida * Redistribution and use in source and binary forms, with or without
12b6cbf720SGianluca Guida * modification, are permitted provided that the following conditions
13b6cbf720SGianluca Guida * are met:
14b6cbf720SGianluca Guida * 1. Redistributions of source code must retain the above copyright
15b6cbf720SGianluca Guida *    notice, this list of conditions and the following disclaimer.
16b6cbf720SGianluca Guida * 2. Redistributions in binary form must reproduce the above copyright
17b6cbf720SGianluca Guida *    notice, this list of conditions and the following disclaimer in the
18b6cbf720SGianluca Guida *    documentation and/or other materials provided with the distribution.
19b6cbf720SGianluca Guida * 3. Neither the name of the University nor the names of its contributors
20b6cbf720SGianluca Guida *    may be used to endorse or promote products derived from this software
21b6cbf720SGianluca Guida *    without specific prior written permission.
22b6cbf720SGianluca Guida *
23b6cbf720SGianluca Guida * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24b6cbf720SGianluca Guida * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25b6cbf720SGianluca Guida * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26b6cbf720SGianluca Guida * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27b6cbf720SGianluca Guida * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28b6cbf720SGianluca Guida * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29b6cbf720SGianluca Guida * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30b6cbf720SGianluca Guida * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31b6cbf720SGianluca Guida * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32b6cbf720SGianluca Guida * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33b6cbf720SGianluca Guida * SUCH DAMAGE.
34b6cbf720SGianluca Guida */
35b6cbf720SGianluca Guida
36b6cbf720SGianluca Guida#include <machine/asm.h>
37b6cbf720SGianluca Guida
38b6cbf720SGianluca Guida#if defined(LIBC_SCCS) && !defined(lint)
39b6cbf720SGianluca Guida#if 0
40b6cbf720SGianluca Guida	RCSID("from: @(#)strncpy.s	5.1 (Berkeley) 5/12/90")
41b6cbf720SGianluca Guida#else
42*84d9c625SLionel Sambuc	RCSID("$NetBSD: strncpy.S,v 1.5 2013/09/07 19:06:29 chs Exp $")
43b6cbf720SGianluca Guida#endif
44b6cbf720SGianluca Guida#endif /* LIBC_SCCS and not lint */
45b6cbf720SGianluca Guida
46b6cbf720SGianluca GuidaENTRY(strncpy)
47*84d9c625SLionel Sambuc	movl	4(%sp),%d0		| return value is toaddr
48*84d9c625SLionel Sambuc	movl	12(%sp),%d1		| count
49*84d9c625SLionel Sambuc	jeq	.Lscdone		| nothing to do
50*84d9c625SLionel Sambuc	movl	8(%sp),%a0		| a0 = fromaddr
51b6cbf720SGianluca Guida	movl	%d0,%a1			| a1 = toaddr
52b6cbf720SGianluca Guida	subql	#1,%d1
53*84d9c625SLionel Sambuc.Lscloop:
54*84d9c625SLionel Sambuc	movb	(%a0)+,(%a1)+		| copy a byte
55*84d9c625SLionel Sambuc#ifndef __mcoldfire__
56*84d9c625SLionel Sambuc	dbeq	%d1,.Lscloop		| loop through low word of d1
57*84d9c625SLionel Sambuc#endif
58*84d9c625SLionel Sambuc	jeq	.Lscpadding		| copied null, padding if necessary
59*84d9c625SLionel Sambuc#ifndef __mcoldfire__
60b6cbf720SGianluca Guida	clrw	%d1			| clear low word of d1
61*84d9c625SLionel Sambuc#endif
62b6cbf720SGianluca Guida	subql	#1,%d1			| adjust count for long copies
63*84d9c625SLionel Sambuc	jcc	.Lscloop		| more room, keep going
64*84d9c625SLionel Sambuc.Lscdone:
65b6cbf720SGianluca Guida#ifdef __SVR4_ABI__
66b6cbf720SGianluca Guida	moveal	%d0,%a0
67b6cbf720SGianluca Guida#endif
68b6cbf720SGianluca Guida	rts
69b6cbf720SGianluca Guida
70*84d9c625SLionel Sambuc.Lscploop:
71*84d9c625SLionel Sambuc	clrb	(%a1)+			| clear a byte
72*84d9c625SLionel Sambuc#ifndef __mcoldfire__
73*84d9c625SLionel Sambuc	dbra	%d1,.Lscploop		| keep going
74b6cbf720SGianluca Guida	clrw	%d1
75*84d9c625SLionel Sambuc#endif
76*84d9c625SLionel Sambuc.Lscpadding:
77b6cbf720SGianluca Guida	subql	#1,%d1
78*84d9c625SLionel Sambuc	jcc	.Lscploop
79*84d9c625SLionel Sambuc	jra	.Lscdone
80*84d9c625SLionel SambucEND(strncpy)
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