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/*
	WARNING: This file was generated by dkct.
	Changes you make here will be lost if dkct is run again!
	You should modify the original source and run dkct on it.
	Original source: dk4bitsh.ctr
*/

/*
Copyright (C) 2015-2017, Dirk Krause

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above opyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.
* Neither the name of the author nor the names of contributors may be used
  to endorse or promote products derived from this software without specific
  prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef DK4BITSH_H_INCLUDED
/** Avoid multiple inclusions. */
#define DK4BITSH_H_INCLUDED 1


#line 10 "dk4bitsh.ctr"

/**	@file	dk4bitsh.h	Bit shifting.
*/

#include "dk4error.h"

/**	Bit shifter.
*/
typedef struct {
  int			pos;	/**< Current bit position. */
  unsigned char		obyte;	/**< Output byte. */
} dk4_bit_shift_t;

#ifdef __cplusplus
extern "C" {
#endif

/**	Initialize a bit shifter before using it.
	@param	bs	Bit shifter to initialize.
	@param	erp	Error report, may be NULL.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS	if bs is NULL.
*/
void
dk4bit_shift_init(dk4_bit_shift_t *bs, dk4_er_t *erp);

/**	Add one byte.
	@param	bs	Bit shifter.
	@param	bit	Bit value, 0 or non-0.
	@param	erp	Error report, may be NULL.
	@return	Action to take, one from:
	- DK4_EDSTM_ACCEPT<br>
	  if the bit was stored in the bit shifter. No action necessary.
	- DK4_EDSTM_FINISHED<br>
	  if one byte was completed by adding the bit.
	  Use dk4bit_shift_output() to retrieve the finished byte.
	- DK4_EDSTM_ERROR<br>
	  if an error occured.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if bs is NULL.
*/
int
dk4bit_shift_add(dk4_bit_shift_t *bs, int bit, dk4_er_t *erp);

/**	Check for unused content in the bit shifter after adding all bits.
	@param	bs	Bit shifter.
	@param	erp	Error report, may be NULL.
	@return	Action to take, one from:
	- DK4_EDSTM_ACCEPT<br>
	  if no action is required.
	- DK4_EDSTM_FINISHED<br>
	  if significant bits are available for a byte.
	  Use dk4bit_shift_output() to retrieve the byte value.
	- DK4_EDSTM_ERROR<br>
	  if an error occured.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if bs is NULL.
*/
int
dk4bit_shift_finish(dk4_bit_shift_t *bs, dk4_er_t *erp);

/**	Retrieve previous completed byte or final incomplete byte.
	@param	bs	Bit shifter.
	@param	erp	Error report, may be NULL.
	@return	Byte value consisting of the last bits added.
*/
unsigned char
dk4bit_shift_output(dk4_bit_shift_t *bs, dk4_er_t *erp);

#ifdef __cplusplus
}
#endif


#endif