1 | /* $NetBSD: strstr.c,v 1.2 2007/06/04 18:19:28 christos Exp $ */ |
2 | |
3 | /*- |
4 | * Copyright (c) 1990, 1993 |
5 | * The Regents of the University of California. All rights reserved. |
6 | * |
7 | * This code is derived from software contributed to Berkeley by |
8 | * Chris Torek. |
9 | * |
10 | * Redistribution and use in source and binary forms, with or without |
11 | * modification, are permitted provided that the following conditions |
12 | * are met: |
13 | * 1. Redistributions of source code must retain the above copyright |
14 | * notice, this list of conditions and the following disclaimer. |
15 | * 2. Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in the |
17 | * documentation and/or other materials provided with the distribution. |
18 | * 3. Neither the name of the University nor the names of its contributors |
19 | * may be used to endorse or promote products derived from this software |
20 | * without specific prior written permission. |
21 | * |
22 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
23 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
24 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
25 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
27 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
28 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
29 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
30 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
31 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
32 | * SUCH DAMAGE. |
33 | */ |
34 | |
35 | #include <sys/cdefs.h> |
36 | #if defined(LIBC_SCCS) && !defined(lint) |
37 | #if 0 |
38 | static char sccsid[] = "@(#)strstr.c 8.1 (Berkeley) 6/4/93" ; |
39 | #else |
40 | __RCSID("$NetBSD: strstr.c,v 1.2 2007/06/04 18:19:28 christos Exp $" ); |
41 | #endif |
42 | #endif /* LIBC_SCCS and not lint */ |
43 | |
44 | #if !defined(_KERNEL) && !defined(_STANDALONE) |
45 | #include <assert.h> |
46 | #include <string.h> |
47 | #else |
48 | #include <sys/param.h> |
49 | #include <lib/libkern/libkern.h> |
50 | #endif |
51 | |
52 | /* |
53 | * Find the first occurrence of find in s. |
54 | */ |
55 | char * |
56 | strstr(const char *s, const char *find) |
57 | { |
58 | char c, sc; |
59 | size_t len; |
60 | |
61 | _DIAGASSERT(s != NULL); |
62 | _DIAGASSERT(find != NULL); |
63 | |
64 | if ((c = *find++) != 0) { |
65 | len = strlen(find); |
66 | do { |
67 | do { |
68 | if ((sc = *s++) == 0) |
69 | return (NULL); |
70 | } while (sc != c); |
71 | } while (strncmp(s, find, len) != 0); |
72 | s--; |
73 | } |
74 | return __UNCONST(s); |
75 | } |
76 | |