usr/src/lib/libbc/libc/gen/common/strstr.c

   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, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 /*
  30  * Get matching substring
  31  */
  32 #include <string.h>
  33
  34 #pragma weak strstr = _strstr
  35
  36 char *
  37 _strstr(s1, s2)
  38         register char *s1, *s2;
  39 {
  40         int s2len = strlen(s2); /* length of the second string */
  41         /*
  42          * If the length of the second string is 0,
  43          *  return the first argument.
  44          */
  45         if (s2len == 0)
  46                 return (s1);
  47
  48         while (strlen(s1) >= s2len) {
  49                 if (strncmp(s1, s2, s2len) == 0)
  50                         return (s1);
  51                 s1++;
  52         }
  53         return (0);
  54 }