Function _rt_wqueue_wait

components/drivers/ipc/waitqueue.c:199–265

* @brief This function will join a thread to the specified waiting queue, the thread will holds a wait or * timeout return on the specified wait queue. * * @param queue is a pointer to the wait queue. * * @param condition is parameters compatible with POSIX standard interface (currently meaningless, just pass in 0). * * @param msec is the timeout value, unit is millise

 * @return   Return 0 if the thread is woken up.
 */
static int _rt_wqueue_wait(rt_wqueue_t *queue, int condition, int msec, int suspend_flag)
{
    rt_tick_t tick;
    rt_thread_t tid = rt_thread_self();
    rt_timer_t  tmr = &(tid->thread_timer);
    struct rt_wqueue_node __wait;
    rt_base_t level;
    rt_err_t ret;

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

    tick = rt_tick_from_millisecond(msec);

    if ((condition) || (tick == 0))
        return 0;

    __wait.polling_thread = rt_thread_self();
    __wait.key = 0;
    __wait.wakeup = __wqueue_default_wake;
    __wait.wqueue = queue;
    rt_list_init(&__wait.list);

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

    /* reset thread error */
    tid->error = RT_EOK;

    if (queue->flag == RT_WQ_FLAG_WAKEUP)
    {
        /* already wakeup */
        goto __exit_wakeup;
    }

    ret = rt_thread_suspend_with_flag(tid, suspend_flag);
    if (ret != RT_EOK)
    {
        rt_spin_unlock_irqrestore(&(queue->spinlock), level);
        /* suspend failed */
        return -RT_EINTR;
    }

    rt_list_insert_before(&(queue->waiting_list), &(__wait.list));

    /* start timer */
    if (tick != (rt_tick_t)RT_WAITING_FOREVER)
    {
        rt_timer_control(tmr,
                         RT_TIMER_CTRL_SET_TIME,
                         &tick);

        rt_timer_start(tmr);
    }
    rt_spin_unlock_irqrestore(&(queue->spinlock), level);

    rt_schedule();

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