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/*
Copyright (C) 2015-2020, Dirk Krause
SPDX-License-Identifier: BSD-3-Clause
*/

/*
	WARNING: This file was generated by the dkct program (see
	http://dktools.sourceforge.net/ for details).
	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
*/

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


#line 10 "dk4bitsh.ctr"

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

#ifndef	DK4CONF_H_INCLUDED
#if	DK4_BUILDING_DKTOOLS4
#include "dk4conf.h"
#else
#include <dktools-4/dk4conf.h>
#endif
#endif

#ifndef	DK4ERROR_H_INCLUDED
#if	DK4_BUILDING_DKTOOLS4
#include "dk4error.h"
#else
#include <dktools-4/dk4error.h>
#endif
#endif


/**	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 const *bs, dk4_er_t *erp);

#ifdef __cplusplus
}
#endif


#endif