1/*	$NetBSD: strstr.c,v 1.1.1.2 2009/03/20 20:26:56 christos Exp $	*/
2
3/*
4 * Copyright (c) 1997-2009 Erez Zadok
5 * Copyright (c) 1990 Jan-Simon Pendry
6 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
7 * Copyright (c) 1990 The Regents of the University of California.
8 * All rights reserved.
9 *
10 * This code is derived from the Free Software Foundation, Inc. GNU utilities.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 *    must display the following acknowledgment:
22 *      This product includes software developed by the University of
23 *      California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 *    may be used to endorse or promote products derived from this software
26 *    without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 *
41 * File: am-utils/libamu/strstr.c
42 *
43 */
44
45#ifdef HAVE_CONFIG_H
46# include <config.h>
47#endif /* HAVE_CONFIG_H */
48#include <am_defs.h>
49#include <amu.h>
50
51
52/* strstr.c -- return the offset of one string within another
53   Copyright (C) 1989, 1990 Free Software Foundation, Inc.
54
55   This program is free software; you can redistribute it and/or modify
56   it under the terms of the GNU General Public License as published by
57   the Free Software Foundation; either version 2, or (at your option)
58   any later version.
59
60   This program is distributed in the hope that it will be useful,
61   but WITHOUT ANY WARRANTY; without even the implied warranty of
62   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
63   GNU General Public License for more details.
64
65   You should have received a copy of the GNU General Public License
66   along with this program; if not, write to the Free Software
67   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
68
69/* Author:
70	Mike Rendell			Department of Computer Science
71	michael@garfield.mun.edu	Memorial University of Newfoundland
72	..!uunet!garfield!michael	St. John's, Nfld., Canada
73	(709) 737-4550			A1C 5S7
74*/
75
76
77/*
78 * Return the starting address of string S2 in S1;
79 * return 0 if it is not found.
80 */
81char *
82strstr(char *s1, char *s2)
83{
84  int i;
85  char *p1;
86  char *p2;
87  char *s = s1;
88
89  for (p2 = s2, i = 0; *s; p2 = s2, i++, s++) {
90    for (p1 = s; *p1 && *p2 && *p1 == *p2; p1++, p2++)
91      ;
92    if (!*p2)
93      break;
94  }
95  if (!*p2)
96    return s1 + i;
97
98  return 0;
99}
100