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/********************************************************************
* *
* THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. *
* USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
* GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
* IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
* *
* THE OggTheora SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
* by the Xiph.Org Foundation and contributors http://www.xiph.org/ *
* *
********************************************************************
function: packing variable sized words into an octet stream
last mod: $Id: bitwise.c 7675 2004-09-01 00:34:39Z xiphmont $
********************************************************************/
#if !defined(_bitpack_H)
# define _bitpack_H (1)
# include <stddef.h>
# include <limits.h>
# include "internal.h"
typedef size_t oc_pb_window;
typedef struct oc_pack_buf oc_pack_buf;
/*Custom bitpacker implementations.*/
# if defined(OC_ARM_ASM)
# include "arm/armbits.h"
# endif
# if !defined(oc_pack_read)
# define oc_pack_read oc_pack_read_c
# endif
# if !defined(oc_pack_read1)
# define oc_pack_read1 oc_pack_read1_c
# endif
# if !defined(oc_huff_token_decode)
# define oc_huff_token_decode oc_huff_token_decode_c
# endif
# define OC_PB_WINDOW_SIZE ((int)sizeof(oc_pb_window)*CHAR_BIT)
/*This is meant to be a large, positive constant that can still be efficiently
loaded as an immediate (on platforms like ARM, for example).
Even relatively modest values like 100 would work fine.*/
# define OC_LOTS_OF_BITS (0x40000000)
struct oc_pack_buf{
const unsigned char *stop;
const unsigned char *ptr;
oc_pb_window window;
int bits;
int eof;
};
void oc_pack_readinit(oc_pack_buf *_b,unsigned char *_buf,long _bytes);
int oc_pack_look1(oc_pack_buf *_b);
void oc_pack_adv1(oc_pack_buf *_b);
/*Here we assume 0<=_bits&&_bits<=32.*/
long oc_pack_read_c(oc_pack_buf *_b,int _bits);
int oc_pack_read1_c(oc_pack_buf *_b);
/* returns -1 for read beyond EOF, or the number of whole bytes available */
long oc_pack_bytes_left(oc_pack_buf *_b);
/*These two functions are implemented locally in huffdec.c*/
/*Read in bits without advancing the bitptr.
Here we assume 0<=_bits&&_bits<=32.*/
/*static int oc_pack_look(oc_pack_buf *_b,int _bits);*/
/*static void oc_pack_adv(oc_pack_buf *_b,int _bits);*/
#endif
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