barrier.h

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// The DAGFrameScheduler is a Multi-Threaded lock free and wait free scheduling library.
// © Copyright 2010 - 2016 BlackTopp Studios Inc.
/* This file is part of The DAGFrameScheduler.

    The DAGFrameScheduler is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
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*/
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*/
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*/
#ifndef _barrier_h
#define _barrier_h

#include "datatypes.h"

#if !defined(SWIG) || defined(SWIG_THREADING) // Do not read when in swig and not in the threading module
#include "atomicoperations.h"
#endif

/// @file
/// @brief The declaration of the @ref Mezzanine::Threading::Barrier Barrier synchronization primitive

namespace Mezzanine
{
    namespace Threading
    {
        /// @brief A synchronization primitive that causes a predefined number of threads to all wait before continuing.
        class MEZZ_LIB Barrier
        {
            protected:
                /// @brief The number of threads to have wait.
                Int32 ThreadGoal;

                /// @brief Does calling wait on this barrier block at presemt
                /// @details 1 waits, and 0 does not any other value indicates a bug
                Int32 IsBlocking;

                /// @brief The number of threads currently waiting.
                Int32 ThreadCurrent;

            public:
                /// @brief Constructor
                /// @param SynchThreadCount The amount of threads that this should wait for. If 0 is passed all threads waiting advance.
                Barrier (const Int32& SynchThreadCount);

                /// @brief Wait until the specified number of threads reach this point.
                /// @return The last thread to reach this point gets true, the others are returned false.
                bool Wait();

                /// @brief Set the Thread count Atomically.
                /// @param NewCount The new amounf threads to sync.
                void SetThreadSyncCount(Int32 NewCount);

        };//Barrier
    }//Threading
}//Mezzanine
#endif