/*  *    crc.c * *	Copyright (C) Aaron Holtzman - May 1999 * *  This file is part of ac3dec, a free Dolby AC-3 stream decoder. *	 *  ac3dec 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, or (at your option) *  any later version. *    *  ac3dec 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 GNU Make; see the file COPYING.  If not, write to *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  * */#include <stdlib.h>#include <stdio.h>#include "ac3.h"#include "crc.h"static uint_16 state;voidcrc_init(void){	state = 0;}voidcrc_process(uint_32 data, uint_32 num_bits){	uint_32 shift_reg;	data <<= 32 - num_bits;	shift_reg = state;	while(num_bits)	{		shift_reg <<= 1;		if((shift_reg >> 16) ^ (data >> 31))			shift_reg = (shift_reg ^ 0x8005);		shift_reg &= 0xffff;		data <<= 1;		num_bits--;	}	state = shift_reg;}intcrc_validate(void){	return(state  == 0);}