mpqc-docs/v3/memshm_8h_source.html

//

// memshm.h

//

// Copyright (C) 1996 Limit Point Systems, Inc.

//

// Author: Curtis Janssen <cljanss@limitpt.com>

// Maintainer: LPS

//

// This file is part of the SC Toolkit.

//

// The SC Toolkit is free software; you can redistribute it and/or modify

// it under the terms of the GNU Library General Public License as published by

// the Free Software Foundation; either version 2, or (at your option)

// any later version.

//

// The SC Toolkit is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU Library General Public License for more details.

//

// You should have received a copy of the GNU Library General Public License

// along with the SC Toolkit; see the file COPYING.LIB.  If not, write to

// the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

//

// The U.S. Government is granted a limited license as per AL 91-7.

//


#ifndef _util_group_memshm_h

#define _util_group_memshm_h


#include <sys/types.h>

#include <sys/ipc.h>

#include <sys/shm.h>

#include <iostream>


#include <util/group/globcnt.h>

#include <util/group/memmsg.h>


#include <util/group/rnglock.h>


namespace sc {


class ShmMemoryGrp: public MsgMemoryGrp {

  private:

    int nregion_;

    int *shmid_;

    void **attach_address_;

    GlobalCounter lock_;

    GlobalCounter *update_;

    void *data_;

    void *memory_;

    Pool *pool_;

    RangeLock *rangelock_; // the locks_ member of the base class is ignored


    void clear_release_count();

    void wait_for_release();

    void note_release();

    void obtain_lock();

    void release_lock();


    void cleanup();

    int attach_memory(void *ataddress, int size);

    void detach_memory();

  public:

    ShmMemoryGrp(const Ref<MessageGrp>& msg);

    ShmMemoryGrp(const Ref<KeyVal>&);

    ~ShmMemoryGrp();


    void set_localsize(size_t);

    void *localdata();


    void *obtain_readwrite(distsize_t offset, size_t size);

    void *obtain_readonly(distsize_t offset, size_t size);

    void *obtain_writeonly(distsize_t offset, size_t size);

    void release_readonly(void *data, distsize_t offset, size_t size);

    void release_writeonly(void *data, distsize_t offset, size_t size);

    void release_readwrite(void *data, distsize_t offset, size_t size);


    void print(std::ostream &o = ExEnv::out0()) const;

};


}


#endif


// Local Variables:

// mode: c++

// c-file-style: "CLJ"

// End: