1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1988 AT&T */ 28 /* All Rights Reserved */ 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 #include "lint.h" 33 #include <string.h> 34 #include <stddef.h> 35 #include <sys/types.h> 36 37 /* 38 * strstr() locates the first occurrence in the string as1 of 39 * the sequence of characters (excluding the terminating null 40 * character) in the string as2. strstr() returns a pointer 41 * to the located string, or a null pointer if the string is 42 * not found. If as2 is "", the function returns as1. 43 */ 44 45 char * 46 strstr(const char *as1, const char *as2) 47 { 48 const char *s1, *s2; 49 const char *tptr; 50 char c; 51 52 s1 = as1; 53 s2 = as2; 54 55 if (s2 == NULL || *s2 == '\0') 56 return ((char *)s1); 57 c = *s2; 58 59 while (*s1) 60 if (*s1++ == c) { 61 tptr = s1; 62 while ((c = *++s2) == *s1++ && c) 63 ; 64 if (c == 0) 65 return ((char *)tptr - 1); 66 s1 = tptr; 67 s2 = as2; 68 c = *s2; 69 } 70 71 return (NULL); 72 } 73