bitfile.h

/***************************************************************************
*                            Bit Stream File Header
*
*   File    : bitfile.h
*   Purpose : Provides definitions and prototypes for a simple library of
*             I/O functions for files that contain data in sizes that aren't
*             integral bytes.
*             An attempt was made to make the functions in this library
*             analogous to functions provided to manipulate byte streams.
*             The functions contained in this library were created with
*             compression algorithms in mind, but may be suited to other
*             applications.
*   Author  : Michael Dipperstein
*   Date    : January 9, 2004
*
****************************************************************************
*
* Bitfile: Bit stream File I/O Routines
* Copyright (C) 2004-2014 by Michael Dipperstein (mdipper@alumni.cs.ucsb.edu)
*
* This file is part of the bit file library.
*
* The bit file library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 3 of the
* License, or (at your option) any later version.
*
* The bit file library 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 Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
*
***************************************************************************/

#ifndef _BITFILE_H_
#define _BITFILE_H_

/***************************************************************************
*                             INCLUDED FILES
***************************************************************************/
#include <stdio.h>

/***************************************************************************
*                            TYPE DEFINITIONS
***************************************************************************/
typedef enum
{
    BF_READ = 0,
    BF_WRITE = 1,
    BF_APPEND= 2,
    BF_NO_MODE
} BF_MODES;

/* incomplete type to hide implementation */
struct bit_file_t;
typedef struct bit_file_t bit_file_t;

/***************************************************************************
*                               PROTOTYPES
***************************************************************************/

/* open/close file */
bit_file_t *BitFileOpen(const char *fileName, const BF_MODES mode);
bit_file_t *MakeBitFile(FILE *stream, const BF_MODES mode);
int BitFileClose(bit_file_t *stream);
FILE *BitFileToFILE(bit_file_t *stream);

/* toss spare bits and byte align file */
int BitFileByteAlign(bit_file_t *stream);

/* fill byte with ones or zeros and write out results */
int BitFileFlushOutput(bit_file_t *stream, const unsigned char onesFill);

/* get/put character */
int BitFileGetChar(bit_file_t *stream);
int BitFilePutChar(const int c, bit_file_t *stream);

/* get/put single bit */
int BitFileGetBit(bit_file_t *stream);
int BitFilePutBit(const int c, bit_file_t *stream);

/* get/put number of bits (most significant bit to least significat bit) */
int BitFileGetBits(bit_file_t *stream, unsigned int *bits, const unsigned int count);
int BitFilePutBits(bit_file_t *stream, unsigned int bits, const unsigned int count);

/***************************************************************************
* get/put a number of bits from numerical types (short, int, long, ...)
*
* For these functions, the first bit in/out is the least significant bit of
* the least significant byte, so machine endiness is accounted for.  Only
* big endian and little endian architectures are currently supported.
*
* NOTE: size is the sizeof() for the data structure pointed to by bits.
***************************************************************************/
int BitFileGetBitsNum(bit_file_t *stream, void *bits, const unsigned int count,
    const size_t size);
int BitFilePutBitsNum(bit_file_t *stream, void *bits, const unsigned int count,
    const size_t size);

#endif /* _BITFILE_H_ */