1*0a6a1f1dSLionel Sambuc /* $NetBSD: strnstr.c,v 1.1 2014/09/24 22:21:33 christos Exp $ */
2*0a6a1f1dSLionel Sambuc
3*0a6a1f1dSLionel Sambuc /*-
4*0a6a1f1dSLionel Sambuc * Copyright (c) 2001 Mike Barcroft <mike@FreeBSD.org>
5*0a6a1f1dSLionel Sambuc * Copyright (c) 1990, 1993
6*0a6a1f1dSLionel Sambuc * The Regents of the University of California. All rights reserved.
7*0a6a1f1dSLionel Sambuc *
8*0a6a1f1dSLionel Sambuc * This code is derived from software contributed to Berkeley by
9*0a6a1f1dSLionel Sambuc * Chris Torek.
10*0a6a1f1dSLionel Sambuc *
11*0a6a1f1dSLionel Sambuc * Redistribution and use in source and binary forms, with or without
12*0a6a1f1dSLionel Sambuc * modification, are permitted provided that the following conditions
13*0a6a1f1dSLionel Sambuc * are met:
14*0a6a1f1dSLionel Sambuc * 1. Redistributions of source code must retain the above copyright
15*0a6a1f1dSLionel Sambuc * notice, this list of conditions and the following disclaimer.
16*0a6a1f1dSLionel Sambuc * 2. Redistributions in binary form must reproduce the above copyright
17*0a6a1f1dSLionel Sambuc * notice, this list of conditions and the following disclaimer in the
18*0a6a1f1dSLionel Sambuc * documentation and/or other materials provided with the distribution.
19*0a6a1f1dSLionel Sambuc * 3. Neither the name of the University nor the names of its contributors
20*0a6a1f1dSLionel Sambuc * may be used to endorse or promote products derived from this software
21*0a6a1f1dSLionel Sambuc * without specific prior written permission.
22*0a6a1f1dSLionel Sambuc *
23*0a6a1f1dSLionel Sambuc * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24*0a6a1f1dSLionel Sambuc * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25*0a6a1f1dSLionel Sambuc * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26*0a6a1f1dSLionel Sambuc * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27*0a6a1f1dSLionel Sambuc * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28*0a6a1f1dSLionel Sambuc * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29*0a6a1f1dSLionel Sambuc * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30*0a6a1f1dSLionel Sambuc * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31*0a6a1f1dSLionel Sambuc * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32*0a6a1f1dSLionel Sambuc * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33*0a6a1f1dSLionel Sambuc * SUCH DAMAGE.
34*0a6a1f1dSLionel Sambuc */
35*0a6a1f1dSLionel Sambuc
36*0a6a1f1dSLionel Sambuc #include <sys/cdefs.h>
37*0a6a1f1dSLionel Sambuc #if defined(LIBC_SCCS) && !defined(lint)
38*0a6a1f1dSLionel Sambuc #if 0
39*0a6a1f1dSLionel Sambuc static char sccsid[] = "@(#)strstr.c 8.1 (Berkeley) 6/4/93";
40*0a6a1f1dSLionel Sambuc #else
41*0a6a1f1dSLionel Sambuc __RCSID("$NetBSD: strnstr.c,v 1.1 2014/09/24 22:21:33 christos Exp $");
42*0a6a1f1dSLionel Sambuc #endif
43*0a6a1f1dSLionel Sambuc #endif /* LIBC_SCCS and not lint */
44*0a6a1f1dSLionel Sambuc /* FreeBSD: head/lib/libc/string/strnstr.c 251069 2013-05-28 20:57:40Z emaste */
45*0a6a1f1dSLionel Sambuc
46*0a6a1f1dSLionel Sambuc #include <string.h>
47*0a6a1f1dSLionel Sambuc
48*0a6a1f1dSLionel Sambuc /*
49*0a6a1f1dSLionel Sambuc * Find the first occurrence of find in s, where the search is limited to the
50*0a6a1f1dSLionel Sambuc * first slen characters of s.
51*0a6a1f1dSLionel Sambuc */
52*0a6a1f1dSLionel Sambuc char *
strnstr(const char * s,const char * find,size_t slen)53*0a6a1f1dSLionel Sambuc strnstr(const char *s, const char *find, size_t slen)
54*0a6a1f1dSLionel Sambuc {
55*0a6a1f1dSLionel Sambuc char c, sc;
56*0a6a1f1dSLionel Sambuc size_t len;
57*0a6a1f1dSLionel Sambuc
58*0a6a1f1dSLionel Sambuc if ((c = *find++) != '\0') {
59*0a6a1f1dSLionel Sambuc len = strlen(find);
60*0a6a1f1dSLionel Sambuc do {
61*0a6a1f1dSLionel Sambuc do {
62*0a6a1f1dSLionel Sambuc if (slen-- < 1 || (sc = *s++) == '\0')
63*0a6a1f1dSLionel Sambuc return NULL;
64*0a6a1f1dSLionel Sambuc } while (sc != c);
65*0a6a1f1dSLionel Sambuc if (len > slen)
66*0a6a1f1dSLionel Sambuc return NULL;
67*0a6a1f1dSLionel Sambuc } while (strncmp(s, find, len) != 0);
68*0a6a1f1dSLionel Sambuc s--;
69*0a6a1f1dSLionel Sambuc }
70*0a6a1f1dSLionel Sambuc return __UNCONST(s);
71*0a6a1f1dSLionel Sambuc }
72