Line data    Source code

       1             : /*      $OpenBSD: strncmp.c,v 1.11 2014/06/10 04:16:57 deraadt Exp $    */
       2             : 
       3             : /*
       4             :  * Copyright (c) 1989 The Regents of the University of California.
       5             :  * All rights reserved.
       6             :  *
       7             :  * Redistribution and use in source and binary forms, with or without
       8             :  * modification, are permitted provided that the following conditions
       9             :  * are met:
      10             :  * 1. Redistributions of source code must retain the above copyright
      11             :  *    notice, this list of conditions and the following disclaimer.
      12             :  * 2. Redistributions in binary form must reproduce the above copyright
      13             :  *    notice, this list of conditions and the following disclaimer in the
      14             :  *    documentation and/or other materials provided with the distribution.
      15             :  * 3. Neither the name of the University nor the names of its contributors
      16             :  *    may be used to endorse or promote products derived from this software
      17             :  *    without specific prior written permission.
      18             :  *
      19             :  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
      20             :  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
      21             :  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
      22             :  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
      23             :  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
      24             :  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
      25             :  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
      26             :  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
      27             :  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
      28             :  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
      29             :  * SUCH DAMAGE.
      30             :  */
      31             : 
      32             : #include <lib/libkern/libkern.h>
      33             : 
      34             : int
      35           0 : strncmp(const char *s1, const char *s2, size_t n)
      36             : {
      37             : 
      38           0 :         if (n == 0)
      39           0 :                 return (0);
      40           0 :         do {
      41           0 :                 if (*s1 != *s2++)
      42           0 :                         return (*(unsigned char *)s1 - *(unsigned char *)--s2);
      43           0 :                 if (*s1++ == 0)
      44             :                         break;
      45           0 :         } while (--n != 0);
      46           0 :         return (0);
      47           0 : }