Function lwp_thread_signal_timedwait

components/lwp/lwp_signal.c:1329–1412

}

rt_err_t lwp_thread_signal_timedwait(rt_thread_t thread, lwp_sigset_t *sigset,
                                     siginfo_t *usi, struct timespec *timeout)
{
    rt_err_t ret;
    lwp_sigset_t saved_sigset;
    lwp_sigset_t blocked_sigset;
    lwp_sigset_t dontwait_sigset;
    int sig;
    struct rt_lwp *lwp = thread->lwp;

    /**
     * Brief: POSIX
     * If one of the signals in set is already pending for the calling thread,
     * sigwaitinfo() will return immediately
     */

    /* Create a mask of signals user dont want or cannot catch */
    _sigdelset(sigset, SIGKILL);
    _sigdelset(sigset, SIGSTOP);
    _signotsets(&dontwait_sigset, sigset);

    LWP_LOCK(lwp);
    sig = _dequeue_signal(thread, &dontwait_sigset, usi);
    LWP_UNLOCK(lwp);
    if (sig)
        return sig;

    /**
     * Brief: POSIX
     * if none of the signals specified by set are pending, sigtimedwait() shall
     * wait for the time interval specified in the timespec structure referenced
     * by timeout.
     *
     * Note: If the pending signal arrives before thread suspend, the suspend
     * operation will return a failure
     */
    _sigandsets(&blocked_sigset, &thread->signal.sigset_mask, &dontwait_sigset);
    _thread_signal_mask(thread, LWP_SIG_MASK_CMD_SET_MASK, &blocked_sigset, &saved_sigset);
    if (timeout)
    {
        rt_tick_t time;
        time = (timeout->tv_sec * RT_TICK_PER_SECOND) + ((timeout->tv_nsec * RT_TICK_PER_SECOND) / NANOSECOND_PER_SECOND);
        /**
         * Brief: POSIX
         * If the timespec structure pointed to by timeout is zero-valued and
         * if none of the signals specified by set are pending, then
         * sigtimedwait() shall return immediately with an error
         */
        if (time == 0)
            return -EAGAIN;

        rt_enter_critical();
        ret = rt_thread_suspend_with_flag(thread, RT_INTERRUPTIBLE);
        rt_timer_control(&(thread->thread_timer),
                         RT_TIMER_CTRL_SET_TIME,
                         &time);
        rt_timer_start(&(thread->thread_timer));
        rt_exit_critical();