odin-detector/odin-data

/*!
 * SharedBufferManager.h
 *
 *  Created on: Feb 18, 2015
 *      Author: Tim Nicholls, STFC Application Engineering Group
 */

#ifndef SHAREDBUFFERMANAGER_H_
#define SHAREDBUFFERMANAGER_H_

#include <string>
#include <stddef.h>

#include <boost/interprocess/shared_memory_object.hpp>
#include <boost/interprocess/mapped_region.hpp>
#include <boost/shared_ptr.hpp>

#include "OdinDataException.h"

namespace OdinData
{

//! SharedBufferManagerException - custom exception class implementing "what" for error string
class SharedBufferManagerException : public OdinDataException {
public:
  SharedBufferManagerException(const std::string what) : OdinDataException(what) { }
};

class SharedBufferManager
{
public:

  typedef struct
  {
    size_t manager_id;
    size_t num_buffers;
    size_t buffer_size;
  } Header;

  SharedBufferManager(const std::string& shared_mem_name, const size_t shared_mem_size,
                      const size_t buffer_size, bool remove_when_deleted=true);
  SharedBufferManager(const std::string& shared_mem_name);

  ~SharedBufferManager();

  const size_t get_manager_id(void) const;
  const size_t get_num_buffers(void) const;
  const size_t get_buffer_size(void) const;

  void* get_buffer_address(const unsigned int buffer) const;

private:

  std::string shared_mem_name_;
  size_t      shared_mem_size_;
  bool        remove_when_deleted_;
  boost::interprocess::shared_memory_object shared_mem_;
  boost::interprocess::mapped_region        shared_mem_region_;
  Header*                                   manager_hdr_;

  static size_t last_manager_id;
};

typedef boost::shared_ptr<SharedBufferManager> SharedBufferManagerPtr;

} // namespace OdinData
#endif /* SHAREDBUFFERMANAGER_H_ */