lib/libutil/disklabel_dkcksum.c

   1 /*      $NetBSD: disklabel_dkcksum.c,v 1.4 2005/05/15 21:01:34 thorpej Exp $    */
   2
   3 /*-
   4  * Copyright (c) 1991, 1993
   5  *      The Regents of the University of California.  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 <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)dkcksum.c   8.1 (Berkeley) 6/5/93";
  36 #else
  37 __RCSID("$NetBSD: disklabel_dkcksum.c,v 1.4 2005/05/15 21:01:34 thorpej Exp $");
  38 #endif
  39 #endif /* not lint */
  40
  41 #include <sys/types.h>
  42 #include <sys/disklabel.h>
  43
  44 #include <util.h>
  45
  46 uint16_t
  47 disklabel_dkcksum(struct disklabel *lp)
  48 {
  49         uint16_t *start, *end;
  50         uint16_t sum;
  51
  52         sum = 0;
  53         start = (uint16_t *)(void *)lp;
  54         end = (uint16_t *)(void *)&lp->d_partitions[lp->d_npartitions];
  55         while (start < end)
  56                 sum ^= *start++;
  57         return (sum);
  58 }