xref: /minix3/lib/libc/string/strndup.c (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)
1*2fe8fb19SBen Gras /*	$NetBSD: strndup.c,v 1.4 2007/07/03 12:11:09 nakayama Exp $	*/
2*2fe8fb19SBen Gras 
3*2fe8fb19SBen Gras /*
4*2fe8fb19SBen Gras  * Copyright (c) 1988, 1993
5*2fe8fb19SBen Gras  *	The Regents of the University of California.  All rights reserved.
6*2fe8fb19SBen Gras  *
7*2fe8fb19SBen Gras  * Redistribution and use in source and binary forms, with or without
8*2fe8fb19SBen Gras  * modification, are permitted provided that the following conditions
9*2fe8fb19SBen Gras  * are met:
10*2fe8fb19SBen Gras  * 1. Redistributions of source code must retain the above copyright
11*2fe8fb19SBen Gras  *    notice, this list of conditions and the following disclaimer.
12*2fe8fb19SBen Gras  * 2. Redistributions in binary form must reproduce the above copyright
13*2fe8fb19SBen Gras  *    notice, this list of conditions and the following disclaimer in the
14*2fe8fb19SBen Gras  *    documentation and/or other materials provided with the distribution.
15*2fe8fb19SBen Gras  * 3. Neither the name of the University nor the names of its contributors
16*2fe8fb19SBen Gras  *    may be used to endorse or promote products derived from this software
17*2fe8fb19SBen Gras  *    without specific prior written permission.
18*2fe8fb19SBen Gras  *
19*2fe8fb19SBen Gras  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20*2fe8fb19SBen Gras  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21*2fe8fb19SBen Gras  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22*2fe8fb19SBen Gras  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23*2fe8fb19SBen Gras  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24*2fe8fb19SBen Gras  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25*2fe8fb19SBen Gras  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26*2fe8fb19SBen Gras  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27*2fe8fb19SBen Gras  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28*2fe8fb19SBen Gras  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29*2fe8fb19SBen Gras  * SUCH DAMAGE.
30*2fe8fb19SBen Gras  */
31*2fe8fb19SBen Gras 
32*2fe8fb19SBen Gras #if HAVE_NBTOOL_CONFIG_H
33*2fe8fb19SBen Gras #include "nbtool_config.h"
34*2fe8fb19SBen Gras #endif
35*2fe8fb19SBen Gras 
36*2fe8fb19SBen Gras #include <sys/cdefs.h>
37*2fe8fb19SBen Gras #if defined(LIBC_SCCS) && !defined(lint)
38*2fe8fb19SBen Gras #if 0
39*2fe8fb19SBen Gras static char sccsid[] = "@(#)strdup.c	8.1 (Berkeley) 6/4/93";
40*2fe8fb19SBen Gras #else
41*2fe8fb19SBen Gras __RCSID("$NetBSD: strndup.c,v 1.4 2007/07/03 12:11:09 nakayama Exp $");
42*2fe8fb19SBen Gras #endif
43*2fe8fb19SBen Gras #endif /* LIBC_SCCS and not lint */
44*2fe8fb19SBen Gras 
45*2fe8fb19SBen Gras #include "namespace.h"
46*2fe8fb19SBen Gras 
47*2fe8fb19SBen Gras #include <assert.h>
48*2fe8fb19SBen Gras #include <errno.h>
49*2fe8fb19SBen Gras #include <stdlib.h>
50*2fe8fb19SBen Gras #include <string.h>
51*2fe8fb19SBen Gras 
52*2fe8fb19SBen Gras #ifdef __weak_alias
__weak_alias(strndup,_strndup)53*2fe8fb19SBen Gras __weak_alias(strndup,_strndup)
54*2fe8fb19SBen Gras #endif
55*2fe8fb19SBen Gras 
56*2fe8fb19SBen Gras #if !HAVE_STRNDUP
57*2fe8fb19SBen Gras char *
58*2fe8fb19SBen Gras strndup(const char *str, size_t n)
59*2fe8fb19SBen Gras {
60*2fe8fb19SBen Gras 	size_t len;
61*2fe8fb19SBen Gras 	char *copy;
62*2fe8fb19SBen Gras 
63*2fe8fb19SBen Gras 	_DIAGASSERT(str != NULL);
64*2fe8fb19SBen Gras 
65*2fe8fb19SBen Gras 	for (len = 0; len < n && str[len]; len++)
66*2fe8fb19SBen Gras 		continue;
67*2fe8fb19SBen Gras 
68*2fe8fb19SBen Gras 	if (!(copy = malloc(len + 1)))
69*2fe8fb19SBen Gras 		return (NULL);
70*2fe8fb19SBen Gras 	memcpy(copy, str, len);
71*2fe8fb19SBen Gras 	copy[len] = '\0';
72*2fe8fb19SBen Gras 	return (copy);
73*2fe8fb19SBen Gras }
74*2fe8fb19SBen Gras #endif /* !HAVE_STRNDUP */
75