1*86d7f5d3SJohn Marino /* $NetBSD: crc.c,v 1.1.1.1 2008/12/22 00:18:12 haad Exp $ */
2*86d7f5d3SJohn Marino
3*86d7f5d3SJohn Marino /*
4*86d7f5d3SJohn Marino * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
5*86d7f5d3SJohn Marino * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
6*86d7f5d3SJohn Marino *
7*86d7f5d3SJohn Marino * This file is part of LVM2.
8*86d7f5d3SJohn Marino *
9*86d7f5d3SJohn Marino * This copyrighted material is made available to anyone wishing to use,
10*86d7f5d3SJohn Marino * modify, copy, or redistribute it subject to the terms and conditions
11*86d7f5d3SJohn Marino * of the GNU Lesser General Public License v.2.1.
12*86d7f5d3SJohn Marino *
13*86d7f5d3SJohn Marino * You should have received a copy of the GNU Lesser General Public License
14*86d7f5d3SJohn Marino * along with this program; if not, write to the Free Software Foundation,
15*86d7f5d3SJohn Marino * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16*86d7f5d3SJohn Marino */
17*86d7f5d3SJohn Marino
18*86d7f5d3SJohn Marino #include "lib.h"
19*86d7f5d3SJohn Marino
20*86d7f5d3SJohn Marino #include "crc.h"
21*86d7f5d3SJohn Marino
22*86d7f5d3SJohn Marino /* Calculate an endian-independent CRC of supplied buffer */
calc_crc(uint32_t initial,const void * buf,uint32_t size)23*86d7f5d3SJohn Marino uint32_t calc_crc(uint32_t initial, const void *buf, uint32_t size)
24*86d7f5d3SJohn Marino {
25*86d7f5d3SJohn Marino static const uint32_t crctab[] = {
26*86d7f5d3SJohn Marino 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
27*86d7f5d3SJohn Marino 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
28*86d7f5d3SJohn Marino 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
29*86d7f5d3SJohn Marino 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
30*86d7f5d3SJohn Marino };
31*86d7f5d3SJohn Marino uint32_t i, crc = initial;
32*86d7f5d3SJohn Marino const uint8_t *data = (const uint8_t *) buf;
33*86d7f5d3SJohn Marino
34*86d7f5d3SJohn Marino for (i = 0; i < size; i++) {
35*86d7f5d3SJohn Marino crc ^= *data++;
36*86d7f5d3SJohn Marino crc = (crc >> 4) ^ crctab[crc & 0xf];
37*86d7f5d3SJohn Marino crc = (crc >> 4) ^ crctab[crc & 0xf];
38*86d7f5d3SJohn Marino }
39*86d7f5d3SJohn Marino return crc;
40*86d7f5d3SJohn Marino }
41