Home | History | Annotate | Line # | Download | only in libamu 
      1 /*	$NetBSD: memcmp.c,v 1.1.1.3 2015/01/17 16:34:18 christos Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1997-2014 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 software contributed to Berkeley by
     11  * Jan-Simon Pendry at Imperial College, London.
     12  *
     13  * Redistribution and use in source and binary forms, with or without
     14  * modification, are permitted provided that the following conditions
     15  * are met:
     16  * 1. Redistributions of source code must retain the above copyright
     17  *    notice, this list of conditions and the following disclaimer.
     18  * 2. Redistributions in binary form must reproduce the above copyright
     19  *    notice, this list of conditions and the following disclaimer in the
     20  *    documentation and/or other materials provided with the distribution.
     21  * 3. Neither the name of the University nor the names of its contributors
     22  *    may be used to endorse or promote products derived from this software
     23  *    without specific prior written permission.
     24  *
     25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     35  * SUCH DAMAGE.
     36  *
     37  *
     38  * File: am-utils/libamu/memcmp.c
     39  *
     40  */
     41 
     42 #ifdef HAVE_CONFIG_H
     43 # include <config.h>
     44 #endif /* HAVE_CONFIG_H */
     45 #include <am_defs.h>
     46 #include <amu.h>
     47 
     48 
     49 /*
     50  * compare two strings for up to length "len".
     51  * this will normally be included on systems that either have no memcmp()
     52  * and no bcmp(), or on systems that have both but the memcmp() is not 8-bit
     53  * clean (such as SunOS 4.1.3).
     54  *
     55  * SunOS 4.x with gcc requires prototype of (const voidp, const voidp, size_t)
     56  */
     57 int
     58 am_memcmp(const voidp s1, const voidp s2, size_t len)
     59 {
     60   unsigned char *ucp1 = (unsigned char *) s1;
     61   unsigned char *ucp2 = (unsigned char *) s2;
     62   int i = len;
     63 
     64   while (i-- > 0)
     65     if (*ucp1++ != *ucp2++)
     66       return (ucp1[-1] >= ucp2[-1] ? 1 : -1);
     67 
     68   return 0;
     69 }
     70