SharedMemory.h

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//==============================================================================================
//  FILENAME    :   SharedMemory.h
//  AUTHOR      :   Michael Yan
//  CREATION    :   3/15/2007
//  Copyright (C) MicroStrategy Incorporated 2007
//  All Rights Reserved
//==============================================================================================
#ifndef MMultiProcess_SharedMemory_h
#define MMultiProcess_SharedMemory_h

#include "SharedMemoryIncl.h"
#include "Base/Defines/StrongPtr.h"
#include "Base/Interfaces/BaseException.h"

#if defined(WIN32) || defined(WIN64)
#include "PDCHeader/PDCtchar.h"
#define MAX_INT_STR 65
#pragma warning(disable:4996)   // '_ui64tow': This function or variable may be unsafe. Consider using _ui64tow_s instead.
#endif

namespace MMultiProcess
{
    typedef unsigned Int32 shm_size_t;

    // Shared memory identifier, platform dependant
    class SharedMemoryID
    {
    public:
        SharedMemoryID(int id) : mSharedMemoryID(id) {}

        int GetID() { return mSharedMemoryID; }
        
#if defined(WIN32) || defined(WIN64)
        void GetID(TCHAR *ipIdStr)
        {
            //Pass me at least TCHAR ipIdStr[65]
            if(ipIdStr != NULL)
                _ui64tot(mSharedMemoryID,ipIdStr,10);       
        } 
#endif

    private:
        int mSharedMemoryID;
    };

    class DLL_SHAREDMEMORY_EXIM SharedMemory
    {
    public:

        virtual ~SharedMemory() throw() {}

        virtual shm_size_t GetTotalSize() = 0;

        virtual void* GetWriteBlock(shm_size_t iReqestSize, shm_size_t& orAcquiredSize, Int64 iTimeOutInMillisecond=-1) = 0;

        virtual void* GetReadBlock(shm_size_t& orBlockSize, Int64 iTimeOutInMillisecond=-1) = 0;

        // Return True if there is available read memory; False if time out.
        virtual bool WaitOnReadMemory(Int64 iTimeOutInMillisecond=-1) = 0;

        virtual void ReleaseBlock(void* ipStartAddr) = 0;

        virtual void* GetHandle() = 0;

        virtual void Delete() = 0;
    };

    enum SHM_ACCESS_MODE
    {
        SHM_READ,
        SHM_WRITE,
        SHM_DUMMY
    };

    typedef MBase::StrongPtr<SharedMemory, MBase::DeleteOperatorGeneric<SharedMemory> > SharedMemoryPtr;

    DLL_SHAREDMEMORY_EXIM SharedMemory* CreateSharedMemory(const SharedMemoryID& iSharedMemId, SHM_ACCESS_MODE iMode = SHM_DUMMY);

    //DLL_SHAREDMEMORY_EXIM SharedMemory* CreateSharedMemory(const SharedMemoryID& iSharedMemId);

    // Instances of this class may be thrown from Event methods.
    class SharedMemoryException : public MBase::BaseException
    {
    };
}

#endif // MMultiProcess_SharedMemory_h