2.11BSD#431 - /usr/src/lib/libc/string/strstr.c

   1: /*-
   2:  * Copyright (c) 1990, 1993
   3:  *	The Regents of the University of California.  All rights reserved.
   4:  *
   5:  * This code is derived from software contributed to Berkeley by
   6:  * Chris Torek.
   7:  *
   8:  * Redistribution and use in source and binary forms, with or without
   9:  * modification, are permitted provided that the following conditions
  10:  * are met:
  11:  * 1. Redistributions of source code must retain the above copyright
  12:  *    notice, this list of conditions and the following disclaimer.
  13:  * 2. Redistributions in binary form must reproduce the above copyright
  14:  *    notice, this list of conditions and the following disclaimer in the
  15:  *    documentation and/or other materials provided with the distribution.
  16:  * 3. All advertising materials mentioning features or use of this software
  17:  *    must display the following acknowledgement:
  18:  *	This product includes software developed by the University of
  19:  *	California, Berkeley and its contributors.
  20:  * 4. Neither the name of the University nor the names of its contributors
  21:  *    may be used to endorse or promote products derived from this software
  22:  *    without specific prior written permission.
  23:  *
  24:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34:  * SUCH DAMAGE.
  35:  */
  36: 
  37: #if defined(LIBC_SCCS) && !defined(lint)
  38: static char sccsid[] = "@(#)strstr.c	8.1.1 (2.11BSD) 1996/1/15";
  39: #endif /* LIBC_SCCS and not lint */
  40: 
  41: #include <string.h>
  42: 
  43: /*
  44:  * Find the first occurrence of find in s.
  45:  */
  46: char *
  47: strstr(s, find)
  48:     register char *s, *find;
  49: {
  50:     register char c;
  51:     char    sc;
  52:     size_t  len;
  53: 
  54:     if ((c = *find++) != 0) {
  55:         len = strlen(find);
  56:         do {
  57:             do {
  58:                 if ((sc = *s++) == 0)
  59:                     return (NULL);
  60:             } while (sc != c);
  61:         } while (strncmp(s, find, len) != 0);
  62:         s--;
  63:     }
  64:     return ((char *)s);
  65: }

Defined functions

Defined variables