tMbox.c

#include "tinyOS.h"

#if TINYOS_ENABLE_MBOX == 1

void tMboxInit(tMbox * mbox, void ** msgBuffer, uint32_t maxCount)
{
    tEventInit(&mbox->event, tEventTypeMbox);

    mbox->msgBuffer = msgBuffer;
    mbox->maxCount = maxCount;
    mbox->read = 0;
    mbox->write = 0;
    mbox->count = 0;
}

uint32_t tMboxWait(tMbox * mbox, void ** msg, uint32_t waitTicks)
{
    uint32_t status = tTaskEnterCritical();

    if(mbox->count > 0)
    {
        --mbox->count;
        *msg = mbox->msgBuffer[mbox->read++];
        mbox->read %= mbox->maxCount;
        tTaskExitCritical(status);
        return tErrorNoError;
    }
    else
    {
        tEventWait(&mbox->event, currentTask, (void *)0, tEventTypeMbox, waitTicks);
        tTaskExitCritical(status);
        tTaskSched();
        *msg = currentTask->eventMsg;
        return currentTask->waitEventResult;
    }
}

uint32_t tMboxNoWaitGet(tMbox * mbox, void ** msg)
{
    uint32_t status = tTaskEnterCritical();

    if(mbox->count > 0)
    {
        --mbox->count;
        *msg = mbox->msgBuffer[mbox->read++];
        mbox->read %= mbox->maxCount;
        tTaskExitCritical(status);
        return tErrorNoError;
    }
    else
    {
        tTaskExitCritical(status);
        return tErrorResourceUnavaliable;
    }
}

uint32_t tMboxNotify(tMbox * mbox, void * msg, uint32_t notifyOption)
{
    uint32_t status = tTaskEnterCritical();

    if(tEventWaitCount(&mbox->event) > 0)
    {
        tTask * task = tEventWakeUp(&mbox->event, (void *)msg, tErrorNoError);
        if(task->prio < currentTask->prio)
        {
            tTaskSched();
        }
    }
    else
    {
        if(mbox->count >= mbox->maxCount)
        {
            tTaskExitCritical(status);
            return tErrorResourceFull;
        }
        if(notifyOption & tMBOXSendFront)
        {
            if(mbox->read <= 0)
            {
                mbox->read = mbox->maxCount - 1;
            }
            else
            {
                --mbox->read;
            }
            mbox->msgBuffer[mbox->read] = msg;
        }
        else
        {
            mbox->msgBuffer[mbox->write++] = msg;
            if(mbox->write >= mbox->maxCount)
            {
                mbox->write = 0;
            }
        }
        mbox->count++;
    }
    tTaskExitCritical(status);
    return tErrorNoError;
}

void tMboxFlush(tMbox * mbox)
{
    uint32_t status = tTaskEnterCritical();

    if(tEventWaitCount(&mbox->event) == 0)
    {
        mbox->read = 0;
        mbox->write = 0;
        mbox->count = 0;
    }

    tTaskExitCritical(status);
}

uint32_t tMboxDestroy(tMbox * mbox)
{
    uint32_t status = tTaskEnterCritical();
    uint32_t count = tEventRemoveAll(&mbox->event, (void *)0, tErrorDel);
    tTaskExitCritical(status);

    if(count > 0)
    {
        tTaskSched();
    }
    return count;
}

void tMboxGetInfo(tMbox * mbox, tMboxInfo * info)
{
    uint32_t status = tTaskEnterCritical();

    info->count = mbox->count;
    info->maxCount = mbox->maxCount;
    info->taskCount = tEventWaitCount(&mbox->event);

    tTaskExitCritical(status);
}

#endif