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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.<2E> You can create as many buffers as you
/// like (within memory limits), and then use this common set of functions to
/// access each buffer.<2E> The buffers are designed for FIFO<46>operation (first
/// in, first out).<2E> This means that the first byte you put in the buffer
/// will be the first one you get when you read out the buffer.<2E> 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.<2E> 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.<2E> 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
//@}