circularbuffer.hh

/*
 * circularbuffer.hh - Class used to represent a circular buffer with a dynamic size.
 * The operations on it are O(1) and the buffer automatically grows to be able to store
 * the data.
 *
 * Romain Gaillard.
 */
 
#ifndef MIDDLEBOX_CIRCULARBUFFER_HH
#define MIDDLEBOX_CIRCULARBUFFER_HH
 
#include <click/vector.hh>
#include <click/bufferpool.hh>
#include <click/bufferpoolnode.hh>
 
CLICK_DECLS
 
class CircularBuffer
{
public:
    CircularBuffer(BufferPool* bufferPool);
 
    ~CircularBuffer();
 
    uint32_t getSize();
 
    uint32_t getCapacity();
 
    uint32_t getStartOffset();
 
    void setStartOffset(uint32_t startOffset);
 
    bool isBlank();
 
    void removeDataAtBeginning(uint32_t newStart);
 
    void addDataAtEnd(const unsigned char* data, uint32_t length);
 
    void getData(uint32_t start, uint32_t length, Vector<unsigned char> &getBuffer);
 
private:
    BufferPool* bufferPool;
    BufferPoolNode* bufferNode;
    uint32_t bufferStart; // Position in the buffer of the beginning of the data
    uint32_t bufferEnd; // Position in the buffer of the end of the data
    uint32_t startOffset;
    uint32_t size; // Current size of the circular buffer (not necessarily the size of the
                   // buffer in the BufferPoolNode, which is the capacity instead).
    bool blank;
    bool useStartOffset; // Indicates whether we use the start offset or not
 
    void increaseBufferSize(uint32_t addSize);
};
 
CLICK_ENDDECLS
 
#endif