compat/strnstr.cc

   1 /*
   2  * Copyright (C) 1996-2015 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #ifndef SQUID_COMPAT_STRNSTR_CC_
  10 #define SQUID_COMPAT_STRNSTR_CC_
  11
  12 /*
  13  *  Shamelessly duplicated from the FreeBSD public sources
  14  *  for use by the Squid Project under GNU Public License.
  15  *
  16  * Update/Maintenance History:
  17  *
  18  *    26-Apr-2008 : Copied from FreeBSD via OpenGrok
  19  *          - added protection around libray headers
  20  *          - added squid_ prefix for uniqueness
  21  *            so we can use it where OS copy is broken.
  22  *
  23  *  Original License and code follows.
  24  */
  25
  26 #include "squid.h"
  27
  28 #if !HAVE_STRNSTR
  29
  30 /*-
  31  * Copyright (c) 2001 Mike Barcroft <mike@FreeBSD.org>
  32  * Copyright (c) 1990, 1993
  33  *  The Regents of the University of California.  All rights reserved.
  34  *
  35  * This code is derived from software contributed to Berkeley by
  36  * Chris Torek.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. Neither the name of the University nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  60  * SUCH DAMAGE.
  61  *
  62  * @(#)strstr.c 8.1 (Berkeley) 6/4/93
  63  * $FreeBSD: src/lib/libc/string/strnstr.c,v 1.2.2.1 2001/12/09 06:50:03 mike Exp $
  64  * $DragonFly: src/lib/libc/string/strnstr.c,v 1.4 2006/03/20 17:24:20 dillon Exp $
  65  */
  66
  67 #if HAVE_SYS_TYPES_H
  68 #include <sys/types.h>
  69 #endif
  70 #include <cstring>
  71
  72 /**
  73  * Find the first occurrence of find in s, where the search is limited to the
  74  * first slen characters of s.
  75  */
  76 const char *
  77 squid_strnstr(const char *s, const char *find, size_t slen)
  78 {
  79     char c, sc;
  80     size_t len;
  81
  82     if ((c = *find++) != '\0') {
  83         len = strlen(find);
  84         do {
  85             do {
  86                 if (slen < 1 || (sc = *s) == '\0')
  87                     return (NULL);
  88                 --slen;
  89                 ++s;
  90             } while (sc != c);
  91             if (len > slen)
  92                 return (NULL);
  93         } while (strncmp(s, find, len) != 0);
  94         --s;
  95     }
  96     return s;
  97 }
  98
  99 #endif /* !HAVE_STRNSTR */
 100 #endif /* SQUID_COMPAT_STRNSTR_CC_ */
 101