ccondition_variable.cpp

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/****************************************************************************
 *
 *  Copyright (c) 2017, Michael Becker (michael.f.becker@gmail.com)
 *
 *  This file is part of the FreeRTOS Add-ons project.
 *
 *  Source Code:
 *  https://github.com/michaelbecker/freertos-addons
 *
 *  Project Page:
 *  http://michaelbecker.github.io/freertos-addons/
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 *  http://michaelbecker.github.io/freertos-addons/docs/html/index.html
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#include "condition_variable.hpp"
#include "thread.hpp"


#ifdef CPP_FREERTOS_CONDITION_VARIABLES


using namespace cpp_freertos;


ConditionVariable::ConditionVariable()
    : Lock(), WaitList()
{
}


void ConditionVariable::AddToWaitList(Thread *thread)
{
    //
    //  Lock the internal condition variable state
    //
    Lock.Lock();

    //
    //  Add the thread to the condition variable wait list.
    //
    WaitList.push_back(thread);

    //
    //  Drop the internal condition variable lock.
    //
    Lock.Unlock();
}


void ConditionVariable::Signal()
{
    //
    //  Lock the internal condition variable state
    //
    Lock.Lock();

    if ( !WaitList.empty() ) {

        Thread *thr = WaitList.front();
        WaitList.pop_front();
        thr->Signal();
    }

    //
    //  Drop the internal condition variable lock.
    //
    Lock.Unlock();
}


void ConditionVariable::Broadcast()
{
    //
    //  Lock the internal condition variable state
    //
    Lock.Lock();

    while ( !WaitList.empty() ) {

        Thread *thr = WaitList.front();
        WaitList.pop_front();
        thr->Signal();
    }

    //
    //  Drop the internal condition variable lock.
    //
    Lock.Unlock();
}

#endif