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/*! \file buffer.h \brief Multipurpose byte buffer structure and methods. */

//*****************************************************************************

//

// File Name	: 'buffer.h'

// Title		: Multipurpose byte buffer structure and methods

// Author		: Pascal Stang - Copyright (C) 2001-2002

// Created		: 9/23/2001

// Revised		: 11/16/2002

// Version		: 1.1

// Target MCU	: any

// Editor Tabs	: 4

//

///	\ingroup general

/// \defgroup buffer Circular Byte-Buffer Structure and Function Library (buffer.c)

/// \code #include "buffer.h" \endcode

/// \par Overview

///		This byte-buffer structure provides an easy and efficient way to store

///		and process a stream of bytes.  You can create as many buffers as you

///		like (within memory limits), and then use this common set of functions to

///		access each buffer.  The buffers are designed for FIFO operation (first

///		in, first out).  This means that the first byte you put in the buffer

///		will be the first one you get when you read out the buffer.  Supported

///		functions include buffer initialize, get byte from front of buffer, add

///		byte to end of buffer, check if buffer is full, and flush buffer.  The

///		buffer uses a circular design so no copying of data is ever necessary.

///		This buffer is not dynamically allocated, it has a user-defined fixed

///		maximum size.  This buffer is used in many places in the avrlib code.

//

// This code is distributed under the GNU Public License

//		which can be found at http://www.gnu.org/licenses/gpl.txt

//

//*****************************************************************************

//@{

#ifndef BUFFER_H

#define BUFFER_H

// structure/typdefs

//! cBuffer structure

typedef struct struct_cBuffer

{

	unsigned char *dataptr;			///< the physical memory address where the buffer is stored

	unsigned short size;			///< the allocated size of the buffer

	unsigned short datalength;		///< the length of the data currently in the buffer

	unsigned short dataindex;		///< the index into the buffer where the data starts

} cBuffer;

// function prototypes

//! initialize a buffer to start at a given address and have given size

void			bufferInit(cBuffer* buffer, unsigned char *start, unsigned short size);

//! get the first byte from the front of the buffer

unsigned char	bufferGetFromFront(cBuffer* buffer);

//! dump (discard) the first numbytes from the front of the buffer

void bufferDumpFromFront(cBuffer* buffer, unsigned short numbytes);

//! get a byte at the specified index in the buffer (kind of like array access)

// ** note: this does not remove the byte that was read from the buffer

unsigned char	bufferGetAtIndex(cBuffer* buffer, unsigned short index);

//! add a byte to the end of the buffer

unsigned char	bufferAddToEnd(cBuffer* buffer, unsigned char data);

//! check if the buffer is full/not full (returns zero value if full)

unsigned short	bufferIsNotFull(cBuffer* buffer);

//! flush (clear) the contents of the buffer

void			bufferFlush(cBuffer* buffer);

#endif

//@}