RtosSyncObject.cpp

//------------------------------------------------------------------------------
//This file is part of embKernel. 
//See license.txt for the full license governing this code.
//------------------------------------------------------------------------------
#include "RtosSyncObject.hpp"
#include "RtosTask.hpp"

RtosSyncObject::RtosSyncObject(int maxCount, int initialCount) {
    mMaxCount = maxCount;
    mCurrentCount = initialCount;
}

RtosSyncObject::~RtosSyncObject() {

}

int RtosSyncObject::internalTake(Rtos::TICK tick, int value) {
    RtosPortable::enterCriticalSection();

    if (mCurrentCount > 0) {
        if (value > mCurrentCount) {
            value = mCurrentCount;
        }
        mCurrentCount -= value;
        return value;
    }

    if (tick == 0) {
        return 0;
    }

    putOnWaitList(Rtos::sCurrentTask, tick, &mWaitingToTake);

    if (value > mCurrentCount) {
        value = mCurrentCount;
    }
    mCurrentCount -= value;
    return value;
}

void RtosSyncObject::internalWakeUpWaitingToTake() {
    RtosListIterable* iterableSyncObj = mWaitingToTake.getFirst();
    if (iterableSyncObj) {
        //Remove from sleeping or suspended list
        RtosTask * task = iterableSyncObj->mTaskOwner;
        task->mIterableCore.mListOwner->remove(task->mIterableCore);
        Rtos::sListReady[task->mPriority].insertAtBeginning(task->mIterableCore);
        RtosPortable::yield();
    }
}

int RtosSyncObject::internalGive(Rtos::TICK tick, int value) {
    RtosPortable::enterCriticalSection();

    int available = mMaxCount - mCurrentCount;
    if (available > 0) {
        if (value > available) {
            value = available;
        }
        mCurrentCount += value;
        return value;
    }

    if (tick == 0) {
        return 0;
    }

    putOnWaitList(Rtos::sCurrentTask, tick, &mWaitingToGive);

    available = mMaxCount - mCurrentCount;

    if (value > available) {
        value = available;
    }
    mCurrentCount += value;
    return value;
}

void RtosSyncObject::internalWakeUpWaitingToGive() {
    RtosListIterable* iterableSyncObj = mWaitingToGive.getFirst();
    if (iterableSyncObj) {
        //Remove from sleeping or suspended list
        RtosTask * task = iterableSyncObj->mTaskOwner;
        task->mIterableCore.mListOwner->remove(task->mIterableCore);
        Rtos::sListReady[task->mPriority].insertAtBeginning(task->mIterableCore);
        RtosPortable::yield();
    }
}

bool RtosSyncObject::putOnWaitList(RtosTask* task, Rtos::TICK tick, RtosList* list) {
    if (tick == 0) {
        return false;
    }

    if (tick != Rtos::TICK_INFINITE) {
        Rtos::putOnSleepingList(task, tick);
    }
    else {
        Rtos::putOnSuspendedList(task);
    }
    task->mIterableSyncObj.mSortValue = 0;
    list->insertSorted(task->mIterableSyncObj);

    RtosPortable::yield();
    RtosPortable::exitCriticalSection();
    RtosPortable::enterCriticalSection();

    return !task->mIsTimeout;
}