CircularBuffer.h

Go to the documentation of this file.

/*
 GRT MIT License
 Copyright (c) <2012> <Nicholas Gillian, Media Lab, MIT>
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of this software
 and associated documentation files (the "Software"), to deal in the Software without restriction,
 including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
 and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
 subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in all copies or substantial
 portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
 LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef GRT_CIRCULAR_BUFFER_HEADER
#define GRT_CIRCULAR_BUFFER_HEADER
#include <iostream>
#include <vector>
#include "GRTTypedefs.h"
#include "ErrorLog.h"

GRT_BEGIN_NAMESPACE

template <class T>
class CircularBuffer{
    public:
    
    CircularBuffer(){
        errorLog.setKey("[ERROR CircularBuffer]");
        bufferSize = 0;
        numValuesInBuffer = 0;
        readPtr = 0;
        writePtr = 0;
        bufferInit = false;
    }
    
    CircularBuffer(const CircularBuffer &rhs){
        errorLog.setKey("[ERROR CircularBuffer]");
        this->bufferSize = 0;
        this->numValuesInBuffer = 0;
        this->readPtr = 0;
        this->writePtr = 0;
        this->bufferInit = false;
            
        if( rhs.bufferInit ){
            this->bufferInit = rhs.bufferInit;
            this->bufferSize = rhs.bufferSize;
            this->numValuesInBuffer = rhs.numValuesInBuffer;
            this->buffer.resize( rhs.bufferSize );
            for(unsigned int i=0; i<rhs.bufferSize; i++){
                this->buffer[i] = rhs.buffer[ i ];
            }
            this->readPtr = rhs.readPtr;
            this->writePtr = rhs.writePtr;
        }
    }
    
    CircularBuffer(unsigned int bufferSize){
        errorLog.setKey("[ERROR CircularBuffer]");
        bufferInit = false;
        resize(bufferSize);
    }
    
    virtual ~CircularBuffer(){
        if( bufferInit ){
            clear();
        }
    }
    
    CircularBuffer& operator=(const CircularBuffer &rhs){
        if( this != &rhs ){
            this->clear();

            if( rhs.bufferInit ){
                this->bufferInit = rhs.bufferInit;
                this->bufferSize = rhs.bufferSize;
                this->numValuesInBuffer = rhs.numValuesInBuffer;
                this->buffer.resize( rhs.bufferSize );
                for(unsigned int i=0; i<rhs.bufferSize; i++){
                    this->buffer[i] = rhs.buffer[ i ];
                }
                this->readPtr = rhs.readPtr;
                this->writePtr = rhs.writePtr;
            }
        }
        return *this;
    }
    
    inline T& operator[](const unsigned int &index){
        return buffer[ (readPtr + index) % bufferSize ];
    }
    
    inline const T& operator[](const unsigned int &index) const{
        return buffer[ (readPtr + index) % bufferSize ];
    }
    
    inline T& operator()(const unsigned int &index){
        return buffer[ index ];
    }
    
    inline const T& operator()(const unsigned int &index) const{
        return buffer[ index ];
    }
    
    bool resize(const unsigned int newBufferSize){
        return resize(newBufferSize,T());
    }
    
    bool resize(const unsigned int newBufferSize,const T &defaultValue){
        
        //Cleanup the old memory
        clear();
        
        if( newBufferSize == 0 ) return false;
        
        //Setup the memory for the new buffer
        bufferSize = newBufferSize;
        buffer.resize(bufferSize,defaultValue);
        numValuesInBuffer = 0;
        readPtr = 0;
        writePtr = 0;
        
        //Flag that the filter has been initialised
        bufferInit = true;
        
        return true;
    }
    
    bool push_back(const T &value){
        
        if( !bufferInit ){
            errorLog << "Can't push_back value to circular buffer as the buffer has not been initialized!" << std::endl;
            return false;
        }
    
  //Add the value to the buffer
        buffer[ writePtr ] = value;

  //Update the write pointer
        writePtr++;
        writePtr = writePtr % bufferSize;
        
        //Check if the buffer is full
        if( ++numValuesInBuffer > bufferSize ){
            numValuesInBuffer = bufferSize;

   //Only update the read pointer if the buffer has been filled
            readPtr++;
         readPtr = readPtr % bufferSize;
        }

        return true;
    }
    
    bool setAllValues(const T &value){
        if( !bufferInit ){
            return false;
        }
        
        for(unsigned int i=0; i<bufferSize; i++){
            buffer[i] = value;
        }
        
        return true;
    }
    
    bool reset(){
  numValuesInBuffer = 0;
  readPtr = 0;
  writePtr = 0;
        return true;
    }
    
    void clear(){
  numValuesInBuffer = 0;
  readPtr = 0;
  writePtr = 0;
  buffer.clear();
  bufferInit = false;
    }
    
    GRT_DEPRECATED_MSG("Use getData() instead!", std::vector< T > getDataAsVector() const );

    Vector< T > getData( const bool rawBuffer = false ) const{
        if( bufferInit ){

            if( rawBuffer ){
                return buffer; //Here we return the entire data buffer
            }else{ //Here we return only valid elements and in order from oldest to newest
                Vector< T > data( numValuesInBuffer );
                for(unsigned int i=0; i<numValuesInBuffer; i++){
                    data[i] = (*this)[i]; //Gets the ordered element
                }
                return data;
            }
        }
        return Vector< T >();
    }
    
    bool getInit() const { return bufferInit; }
    
    bool getBufferFilled() const { return bufferInit ? numValuesInBuffer==bufferSize : false; }
    
    unsigned int getSize() const { return bufferInit ? bufferSize : 0; }
    
    unsigned int getNumValuesInBuffer() const { return bufferInit ? numValuesInBuffer : 0; }
    
    unsigned int getReadPointerPosition() const { return bufferInit ? readPtr : 0; }
    
    unsigned int getWritePointerPosition() const { return bufferInit ? writePtr : 0; }
    
    T getBack() const {
        if( !bufferInit ) return T();
        return buffer[ (readPtr + numValuesInBuffer - 1) % bufferSize ];
    }
    
protected:
    bool bufferInit;
    unsigned int bufferSize;
    unsigned int numValuesInBuffer;
    unsigned int readPtr;
    unsigned int writePtr;
    Vector< T > buffer;
    
    ErrorLog errorLog;
};

//Deprecated function
template< class T > std::vector< T > CircularBuffer< T >::getDataAsVector() const{ return getData(); };

GRT_END_NAMESPACE

#endif //GRT_CIRCULAR_BUFFER_HEADER