NetworkBuffer.h

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#ifndef NETWORK_BUFFER_H_
#define NETWORK_BUFFER_H_

/*! This is used to incrementally build up a buffer to be sent over
 *  the network , so that only one call to the socket write function
 *  needs to be made. */
class NetworkBuffer {
public:
  
  //! constructor
  NetworkBuffer() : buf(NULL), offset(0), bufSize(1024) {
    buf = new byte[bufSize];
  }

  //! destructor
  virtual ~NetworkBuffer() {
    delete[] buf;
  }

  //! Template for adding a single item to the buffer, such as a struct or an int
  template <class T> bool addItem(T item) {
    if (offset+sizeof(T) > (unsigned int)bufSize)
      return false;
    
    *(T *)(buf+offset) = item;
    offset += sizeof(T);
    return true;
  }

  //! Template for adding a buffer such with a size to the network buffer
  bool addBuffer(byte *src, int size) {
    if (!addItem(size) || (offset+size > bufSize))
      return false;

    memcpy(buf+offset, src, size);
    offset += size;
    return true;
  }

  //! Returns the current size of the buffer
  int getSize() { return offset; }

  //! Returns a const pointer to the buffer, for debugging networking code
  const byte* getBytes() { return buf; }

  //! Sends the buffer over the given socket
  bool send(Socket *sck) {
    if (sck->write(buf, offset) != static_cast<int>(offset)) {
      std::cout << "Error sending buffer" << std::endl;
      return false;
    }
    
    return true;
  }
  
protected:
  byte *buf; //!< the buffer being built
  size_t offset; //!< current position in #buf
  size_t bufSize; //!< size of memory region at #buf

private:
  NetworkBuffer(NetworkBuffer&); //!< do not call
  NetworkBuffer &operator=(const NetworkBuffer&); //!< do not call
};

#endif