Function _rt_event_recv

src/ipc.c:2098–2223

* @brief This function will receive an event from event object. if the event is unavailable, the thread shall wait for * the event up to a specified time. * * @note If there are threads suspended on this semaphore, the first thread in the list of this semaphore object * will be resumed, and a thread scheduling (rt_schedule) will be executed. * If no threads are susp

 *           If the return value is any other values, it means that the semaphore release failed.
 */
static rt_err_t _rt_event_recv(rt_event_t   event,
                               rt_uint32_t  set,
                               rt_uint8_t   option,
                               rt_int32_t   timeout,
                               rt_uint32_t *recved,
                               int suspend_flag)
{
    struct rt_thread *thread;
    rt_base_t level;
    rt_base_t status;
    rt_err_t ret;

    /* parameter check */
    RT_ASSERT(event != RT_NULL);
    RT_ASSERT(rt_object_get_type(&event->parent.parent) == RT_Object_Class_Event);

    /* current context checking */
    RT_DEBUG_SCHEDULER_AVAILABLE(RT_TRUE);

    if (set == 0)
        return -RT_ERROR;

    /* initialize status */
    status = -RT_ERROR;
    /* get current thread */
    thread = rt_thread_self();
    /* reset thread error */
    thread->error = -RT_EINTR;

    RT_OBJECT_HOOK_CALL(rt_object_trytake_hook, (&(event->parent.parent)));

    level = rt_spin_lock_irqsave(&(event->spinlock));

    /* check event set */
    if (option & RT_EVENT_FLAG_AND)
    {
        if ((event->set & set) == set)
            status = RT_EOK;
    }
    else if (option & RT_EVENT_FLAG_OR)
    {
        if (event->set & set)
            status = RT_EOK;
    }
    else
    {
        /* either RT_EVENT_FLAG_AND or RT_EVENT_FLAG_OR should be set */
        RT_ASSERT(0);
    }

    if (status == RT_EOK)
    {
        thread->error = RT_EOK;

        /* set received event */
        if (recved)
            *recved = (event->set & set);