bit.h

00001 /*
00002  * libmad - MPEG audio decoder library
00003  * Copyright (C) 2000-2004 Underbit Technologies, Inc.
00004  *
00005  * This program is free software; you can redistribute it and/or modify
00006  * it under the terms of the GNU General Public License as published by
00007  * the Free Software Foundation; either version 2 of the License, or
00008  * (at your option) any later version.
00009  *
00010  * This program is distributed in the hope that it will be useful,
00011  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  * GNU General Public License for more details.
00014  *
00015  * You should have received a copy of the GNU General Public License
00016  * along with this program; if not, write to the Free Software
00017  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
00018  *
00019  * $Id: bit.h,v 1.1 2010/11/23 20:12:57 andy Exp $
00020  */
00021 
00022 # ifndef LIBMAD_BIT_H
00023 # define LIBMAD_BIT_H
00024 
00025 struct mad_bitptr {
00026   unsigned char const *byte;
00027   unsigned short cache;
00028   unsigned short left;
00029 };
00030 
00031 void mad_bit_init(struct mad_bitptr *, unsigned char const *);
00032 
00033 # define mad_bit_finish(bitptr)     /* nothing */
00034 
00035 unsigned int mad_bit_length(struct mad_bitptr const *,
00036                 struct mad_bitptr const *);
00037 
00038 # define mad_bit_bitsleft(bitptr)  ((bitptr)->left)
00039 unsigned char const *mad_bit_nextbyte(struct mad_bitptr const *);
00040 
00041 void mad_bit_skip(struct mad_bitptr *, unsigned int);
00042 unsigned long mad_bit_read(struct mad_bitptr *, unsigned int);
00043 void mad_bit_write(struct mad_bitptr *, unsigned int, unsigned long);
00044 
00045 unsigned short mad_bit_crc(struct mad_bitptr, unsigned int, unsigned short);
00046 
00047 # endif