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/*
* crc6.c
*
* $Id$
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include "config.h"
#include <glib.h>
#include "crc6.h"
guint16 update_crc6_by_bytes(guint16 crc6, guint8 byte1, guint8 byte2) {
int bit;
guint32 remainder = ( byte1<<8 | byte2 ) << 6;
guint32 polynomial = 0x6F << 15;
for (bit = 15;
bit >= 0;
--bit)
{
if (remainder & (0x40 << bit))
{
remainder ^= polynomial;
}
polynomial >>= 1;
}
return (guint16)(remainder ^ crc6);
}
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