ALACBitUtilities.h

/*
 * Copyright (c) 2011 Apple Inc. All rights reserved.
 *
 * @APPLE_APACHE_LICENSE_HEADER_START@
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 * @APPLE_APACHE_LICENSE_HEADER_END@
 */
 
/*=============================================================================
    File:       ALACBitUtilities.h
    
    $NoKeywords: $
=============================================================================*/
 
#ifndef __ALACBITUTILITIES_H
#define __ALACBITUTILITIES_H
 
#include <stdint.h>
 
#ifndef MIN
#define MIN(x, y)           ( (x)<(y) ?(x) :(y) )
#endif //MIN
#ifndef MAX
#define MAX(x, y)           ( (x)>(y) ?(x): (y) )
#endif //MAX
 
#ifndef nil
#define nil NULL
#endif
 
#define RequireAction(condition, action)            if (!(condition)) { action }
#define RequireActionSilent(condition, action)          if (!(condition)) { action }
#define RequireNoErr(condition, action)         if ((condition)) { action }
 
#ifdef __cplusplus
extern "C" {
#endif
 
enum
{
    ALAC_noErr = 0
};
    
 
typedef enum
{
    
    ID_SCE = 0,                     /* Single Channel Element   */
    ID_CPE = 1,                     /* Channel Pair Element     */
    ID_CCE = 2,                     /* Coupling Channel Element */
    ID_LFE = 3,                     /* LFE Channel Element      */
    ID_DSE = 4,                     /* not yet supported        */
    ID_PCE = 5,
    ID_FIL = 6,
    ID_END = 7
} ELEMENT_TYPE;
 
// types
typedef struct BitBuffer
{
    uint8_t *       cur;
    uint8_t *       end;
    uint32_t        bitIndex;
    uint32_t        byteSize;
    
} BitBuffer;
 
/*
    BitBuffer routines
    - these routines take a fixed size buffer and read/write to it
    - bounds checking must be done by the client
*/
void    BitBufferInit( BitBuffer * bits, uint8_t * buffer, uint32_t byteSize );
uint32_t    BitBufferRead( BitBuffer * bits, uint8_t numBits );   // note: cannot read more than 16 bits at a time
uint8_t BitBufferReadSmall( BitBuffer * bits, uint8_t numBits );
uint8_t BitBufferReadOne( BitBuffer * bits );
uint32_t    BitBufferPeek( BitBuffer * bits, uint8_t numBits );   // note: cannot read more than 16 bits at a time
uint32_t    BitBufferPeekOne( BitBuffer * bits );
uint32_t    BitBufferUnpackBERSize( BitBuffer * bits );
uint32_t    BitBufferGetPosition( BitBuffer * bits );
void    BitBufferByteAlign( BitBuffer * bits, int32_t addZeros );
void    BitBufferAdvance( BitBuffer * bits, uint32_t numBits );
void    BitBufferRewind( BitBuffer * bits, uint32_t numBits );
void    BitBufferWrite( BitBuffer * bits, uint32_t value, uint32_t numBits );
void    BitBufferReset( BitBuffer * bits);
 
 
#ifdef __cplusplus
}
#endif
 
#endif  /* __BITUTILITIES_H */