ps_outbuffer.h

/*
 * Developer : Alexey Zakharov (alexey.zakharov@vectioneer.com)
 * All rights reserved. Copyright (c) 2015 VECTIONEER.
 */
 
#ifndef PS_OUTBUFFER_H
#define PS_OUTBUFFER_H
 
#include "ps_datacontainer.h"
#include <atomic>
#include <shared_mutex>
 
namespace mcx {
 
namespace parameter_server {
 
class OutputBuffer {
  static constexpr unsigned int BUFFER_SIZE = 16;
  static constexpr unsigned int BUFFER_MASK{BUFFER_SIZE - 1};
 
public:
  OutputBuffer();
 
  virtual ~OutputBuffer();
 
  OutputBuffer(const OutputBuffer&) = delete;
 
  OutputBuffer& operator=(const OutputBuffer&) = delete;
 
  bool allocate(unsigned int element_size);
 
  void deallocate();
 
  void init(const DataContainer& in);
 
  void write(const DataContainer& in);
 
  unsigned int read(DataContainer* dst);
 
  unsigned int readWithConversion(DataContainer* dst, const ConversionData& conversion);
 
  static constexpr unsigned int size() { return BUFFER_SIZE; }
 
  unsigned int pos() const { return enqueue_pos_.load(std::memory_order_acquire); }
 
private:
  struct Cell {
#if __cplusplus >= 201703L
    std::shared_mutex guard;
#else
    std::shared_timed_mutex guard;
#endif
    DataContainer data;
  };
  Cell* buffer_;
  std::atomic<unsigned int> enqueue_pos_{};
};
 
} // namespace parameter_server
 
} // namespace mcx
 
#endif /* PS_OUTBUFFER_H */