getbits.h

SEAL是DOS 下的32位保护模式的GUI程序

/******************************************************************
 * SEAL 2.0                                                       *
 * Copyright (c) 1999-2002 SEAL Developers. All Rights Reserved.  *
 *                                                                *
 * Web site: http://sealsystem.sourceforge.net/                   *
 * E-mail (current maintainer): [e-mail]      *
 ******************************************************************/

/*
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/* this file is a part of amp software, (C) tomislav uzelac 1996,1997
*/
 
/* getbits.h
 *
 * Created by: tomislav uzelac  Apr 1996
 */

/* gethdr() error codes
*/
#define GETHDR_ERR 0x1
#define GETHDR_NS  0x2
#define GETHDR_FL1 0x4
#define GETHDR_FL2 0x8
#define GETHDR_FF  0x10
#define GETHDR_SYN 0x20
#define GETHDR_EOF 0x30

/* buffer for the 'bit reservoir'
*/
#define BUFFER_SIZE     4096
#define BUFFER_AUX      2048
extern unsigned char buffer[];
extern int append,data,f_bdirty,bclean_bytes;
  
/* exports
*/
extern int fillbfr(unsigned int advance);
extern unsigned int getbits(int n);
extern int gethdr(struct AUDIO_HEADER *header);
extern void getcrc();
extern void getinfo(struct AUDIO_HEADER *header,struct SIDE_INFO *info);
extern int dummy_getinfo(int n);
extern int rewind_stream(int nbytes);


#ifdef GETBITS

/* buffer, AUX is used in case of input buffer "overflow", and its contents
 * are copied to the beginning of the buffer
*/
unsigned char buffer[BUFFER_SIZE+BUFFER_AUX];

/* buffer pointers: append counts in bytes, data in bits
 */
int append,data;

/* bit reservoir stuff. f_bdirty must be set to TRUE when starting play!
 */
int f_bdirty,bclean_bytes;
 
/* internal buffer, _bptr holds the position in _bits_
 */
static unsigned char _buffer[32];
static int _bptr;


/* buffer and bit manipulation functions
 */
static inline int _fillbfr(unsigned int size);
static inline int readsync();
static inline int get_input(unsigned char* bp, unsigned int size);
static inline unsigned int _getbits(int n);
int fillbfr(unsigned int advance);
unsigned int getbits(int n);
int dummy_getinfo(int n);
int rewind_stream(int nbytes);

/* header and side info parsing stuff 
 */
static inline void parse_header(struct AUDIO_HEADER *header);
static inline int header_sanity_check(struct AUDIO_HEADER *header);

int gethdr(struct AUDIO_HEADER *header);
void getcrc();
void getinfo(struct AUDIO_HEADER *header,struct SIDE_INFO *info);  

#endif /* GETBITS */