text: //=============================================================================================================
  /**
   * @file     shmemsocket.h
   * @author   Lorenz Esch <lesch@mgh.harvard.edu>;
   *           Matti Hamalainen <msh@nmr.mgh.harvard.edu>;
   *           Christoph Dinh <chdinh@nmr.mgh.harvard.edu>
   * @version  dev
   * @date     July, 2012
   *
   * @section  LICENSE
   *
   * Copyright (C) 2012, Lorenz Esch, Matti Hamalainen, Christoph Dinh. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modification, are permitted provided that
   * the following conditions are met:
   *     * Redistributions of source code must retain the above copyright notice, this list of conditions and the
   *       following disclaimer.
   *     * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
   *       the following disclaimer in the documentation and/or other materials provided with the distribution.
   *     * Neither the name of MNE-CPP authors nor the names of its contributors may be used
   *       to endorse or promote products derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
   * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   *
   * @brief     declaration of the ShmemSocket Class.
   *
   */
  
  #ifndef SHMEMSOCKET_H
  #define SHMEMSOCKET_H
  
  //*************************************************************************************************************
  //=============================================================================================================
  // INCLUDES
  //=============================================================================================================
  
  #include "types_definitions.h"
  
  
  //*************************************************************************************************************
  //=============================================================================================================
  // QT INCLUDES
  //=============================================================================================================
  
  #include <QObject>
  
  
  //*************************************************************************************************************
  //=============================================================================================================
  // FORWARD DECLARATIONS
  //=============================================================================================================
  
  namespace FIFFLIB {
      class FiffTag;
  }
  
  
  //*************************************************************************************************************
  //=============================================================================================================
  // DEFINE NAMESPACE NEUROMAGRTSERVERPLUGIN
  //=============================================================================================================
  
  namespace NEUROMAGRTSERVERPLUGIN
  {
  
  
  //*************************************************************************************************************
  //=============================================================================================================
  // NEUROMAGRTSERVERPLUGIN FORWARD DECLARATIONS
  //=============================================================================================================
  
  
  
  //=============================================================================================================
  /**
   * DECLARE CLASS ShmemSocket
   *
   * @brief The ShmemSocket class provides...
   */
  
  class ShmemSocket : public QObject
  {
      Q_OBJECT
  
  public:
      explicit ShmemSocket(QObject *parent = 0);
  
      virtual ~ShmemSocket();
  
      //=========================================================================================================
      /**
       * Receive one tag from the data server.
       *
       * This routine reads a message from the data server
       * socket and grabs the data. The data may actually
       * be in a shared memory segment noted in the message.
       *
       * The id parameter is needed for two purposes. The
       * data transfer mechanism varies depending on the client
       * number. Clients with id above 10000 use shared memory
       * transfer while other used a regular file to transfer the
       * data.It is needed also if the conndedtion needs to be
       * closed after an error.
       *
       * Ported from client_socket.c
       *
       * @param[in] p_pTag ToDo
       *
       * \return Status OK or FAIL.
       */
      int receive_tag (QSharedPointer<FIFFLIB::FiffTag>& p_pTag);
  
      //ToDo Connect is different? to: telnet localhost collector ???
      //=========================================================================================================
      /**
       * Connect to the data server process
       *
       * @return
       */
      bool connect_client ();
  
      //=========================================================================================================
      /**
       * Disconnect from the data server process
       *
       * @return
       */
      int disconnect_client ();
  
      //=========================================================================================================
      /*
       * Select tags that we are not interested in!
       *
       */
      void set_data_filter (int *kinds, int nkind);
  
      //=========================================================================================================
      /**
       *
       * @return
       */
      void close_socket ();
  
      //=========================================================================================================
      /**
       *
       * @return
       */
      int connect_disconnect (int sock,int id);
  
      //=========================================================================================================
      /**
       * Filter out some large data blocks
       * which are not of interest
       *
       * @return
       */
      int interesting_data (int kind);
  
  private:
      //Ported from shmem.c
      //=========================================================================================================
      /**
       *
       * @return
       */
      dacqShmBlock get_shmem();
  
      //=========================================================================================================
      /**
       * Initialize data acquisition shared memory segment
       *
       * @return
       */
      int init_shmem();
  
      //=========================================================================================================
      /**
       * Release the shared memory
       *
       * @return
       */
      int release_shmem();
  
      //=========================================================================================================
      /**
       *
       * @return
       */
      FILE* open_fif (char *name);
  
      //=========================================================================================================
      /**
       *
       *
       * @param[in] fd     File to read from
       * @param[in] pos    Position in file
       * @param[in] size   How long
       * @param[in] data   Put data here
       *
       * @return
       */
      int read_fif (FILE *fd, long pos, size_t size, char *data);
  
  private:
      int*            filter_kinds;   /**< Filter these tags */
      int             nfilt;          /**< How many are they */
  
      int             shmid;
      dacqShmBlock    shmptr;
  
      int             m_iShmemSock;
      int             m_iShmemId;
  
      FILE*           fd;             /**<  The temporary file */
      FILE*           shmem_fd;
      char*           filename;
  
      FILE*           read_fd;
  };
  
  } // NAMESPACE
  
  #endif // SHMEMSOCKET_H
  