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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: dk4rld.ctr
*/

#ifndef DK4RLD_H_INCLUDED
/** Avoid multiple inclusions. */
#define DK4RLD_H_INCLUDED 1


#line 9 "dk4rld.ctr"

/**	@file	dk4rld.h	Run-length decoder.

Use dk4rld_init() to initialize the decoder before feeding data to it.

Feed the encoded data into the decoder byte by byte, use the
dk4rld_add() function.
If the function returns DK4_EDSTM_ACCEPT, the input was successfully stored
into the internal data structures, not need for further action.
If the function returns DK4_EDSTM_FINISHED, an output secquence was
completed, either a run or a literal byte sequence. Use dk4rld_output()
to retrieve output data.
If the dk4rld_add function returns DK4_EDSTM_STOP, an end of data
(EOD) marker was found; do not feed further bytes into the decoder.

After feeding all input bytes into the decoder, use dk4rld_finish() to check
syntax. If the function returns DK4_EDSTM_ERROR, the input data stream
was not properly run-length encoded.
*/


#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

/**	Run length decoder.
*/
typedef struct {
  unsigned char		ob[128];	/**< Output buffer. */
  size_t		oused;		/**< Number of used bytes in ob. */
  size_t		ll;		/**< Number of expected bytes. */
  int			st;		/**< Current state. */
} dk4_rl_dec_t;


#ifdef __cplusplus
extern "C" {
#endif

/**	Initialize decoder.
	@param	dec	Decoder to initialize.
	@param	erp	Error report, may be NULL.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS	if enc is NULL.
*/
void
dk4rld_init(dk4_rl_dec_t *dec, dk4_er_t *erp);

/**	Add one encoded byte to decoder.
	@param	dec	Decoder.
	@param	inbyte	Byte to process.
	@param	erp	Error report, may be NULL.
	@return	Action to take, one from:
	- DK4_EDSTM_ACCEPT<br>
	  if the byte was successfully added
	  to the internal data structures, no further action necessary.
	- DK4_EDSTM_FINISHED<br>
	  if output is available, use dk4rld_output() to retrieve output.
	- DK4_EDSTM_STOP<br>
	  if an EOD marker was detected. Do not feed further bytes
	  to the decoder.
	- DK4_EDSTM_ERROR<br>
	  if an error occured.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS	if enc is NULL.
*/
int
dk4rld_add(dk4_rl_dec_t *dec, unsigned char inbyte, dk4_er_t *erp);

/**	Finish decoding.
	@param	dec	Decoder.
	@param	erp	Error report, may be NULL.
	@return	Action to take, one from:
	- DK4_EDSTM_ACCEPT<br>
	  if no remaining data is stored in the decoder, no further
	  action necessary.
	- DK4_EDSTM_FINISHED<br>
	  if output is available, use dk4rld_output() to retrieve output.
	- DK4_EDSTM_ERROR<br>
	  if an error occured.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if enc is NULL.
	- DK4_E_SYNTAX<br>
	  if data indicated by the run-length byte or literally-length
	  byte is missing.
*/
int
dk4rld_finish(dk4_rl_dec_t *dec, dk4_er_t *erp);

/**	Retrieve decoder output.
	@param	dptr	Address of pointer to set to decoder output,
			should be initialized to NULL.
	@param	szptr	Address of variable to receive buffer size,
			should be initialized to 0.
	@param	dec	Decoder.
	@param	erp	Error report, may be NULL.
	@return	1 if data is available, 0 otherwise.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS	if enc is NULL.
*/
int
dk4rld_output(
  const unsigned char	**dptr,
  size_t		 *szptr,
  dk4_rl_dec_t	const	 *dec,
  dk4_er_t		 *erp
);

#ifdef __cplusplus
}
#endif


#endif