xref: /illumos-gate/usr/src/lib/libc/port/gen/strncpy.c (revision 7257d1b4)
17c478bd9Sstevel@tonic-gate /*
27c478bd9Sstevel@tonic-gate  * CDDL HEADER START
37c478bd9Sstevel@tonic-gate  *
47c478bd9Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*7257d1b4Sraf  * Common Development and Distribution License (the "License").
6*7257d1b4Sraf  * You may not use this file except in compliance with the License.
77c478bd9Sstevel@tonic-gate  *
87c478bd9Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
97c478bd9Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
107c478bd9Sstevel@tonic-gate  * See the License for the specific language governing permissions
117c478bd9Sstevel@tonic-gate  * and limitations under the License.
127c478bd9Sstevel@tonic-gate  *
137c478bd9Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
147c478bd9Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
157c478bd9Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
167c478bd9Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
177c478bd9Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
187c478bd9Sstevel@tonic-gate  *
197c478bd9Sstevel@tonic-gate  * CDDL HEADER END
207c478bd9Sstevel@tonic-gate  */
21*7257d1b4Sraf 
227c478bd9Sstevel@tonic-gate /*
23*7257d1b4Sraf  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
247c478bd9Sstevel@tonic-gate  * Use is subject to license terms.
257c478bd9Sstevel@tonic-gate  */
267c478bd9Sstevel@tonic-gate 
277c478bd9Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
287c478bd9Sstevel@tonic-gate /*	  All Rights Reserved  	*/
297c478bd9Sstevel@tonic-gate 
30*7257d1b4Sraf #pragma ident	"%Z%%M%	%I%	%E% SMI"
317c478bd9Sstevel@tonic-gate 
32*7257d1b4Sraf #include "lint.h"
337c478bd9Sstevel@tonic-gate #include <string.h>
347c478bd9Sstevel@tonic-gate #include <sys/types.h>
357c478bd9Sstevel@tonic-gate 
367c478bd9Sstevel@tonic-gate /*
377c478bd9Sstevel@tonic-gate  * Copy s2 to s1, truncating or null-padding to always copy n bytes
387c478bd9Sstevel@tonic-gate  * return s1
397c478bd9Sstevel@tonic-gate  */
407c478bd9Sstevel@tonic-gate char *
417c478bd9Sstevel@tonic-gate strncpy(char *s1, const char *s2, size_t n)
427c478bd9Sstevel@tonic-gate {
437c478bd9Sstevel@tonic-gate 	char *os1 = s1;
447c478bd9Sstevel@tonic-gate 
457c478bd9Sstevel@tonic-gate 	n++;
467c478bd9Sstevel@tonic-gate 	while ((--n != 0) && ((*s1++ = *s2++) != '\0'))
477c478bd9Sstevel@tonic-gate 		;
487c478bd9Sstevel@tonic-gate 	if (n != 0)
497c478bd9Sstevel@tonic-gate 		while (--n != 0)
507c478bd9Sstevel@tonic-gate 			*s1++ = '\0';
517c478bd9Sstevel@tonic-gate 	return (os1);
527c478bd9Sstevel@tonic-gate }
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