// this will set the default inactivity timeout using this event timer and our uid
uint32_t e3x_channel_timeout(e3x_channel_t c, e3x_event_t ev, uint32_t timeout)
{
if(!c) return 0;
// un-set any
if(ev != c->ev)
{
// cancel and clearn any previous timer state
c->timeout = 0;
if(c->ev) e3x_event_set(c->ev,NULL,c->uid,0);
c->ev = NULL;
lob_free(c->timer);
c->timer = NULL;
}
// no event manager, no timeouts
if(!ev) return 0;
// no timeout, just return how much time is left
if(!timeout) return _time_left(c);
// add/update new timeout
c->tsince = util_sys_seconds(); // start timer now
c->timeout = timeout;
c->ev = ev;
c->timer = lob_new();
lob_set_uint(c->timer,"c",c->id);
lob_set(c->timer, "id", c->uid);
lob_set(c->timer, "err", "timeout");
e3x_event_set(c->ev, c->timer, lob_get(c->timer, "id"), timeout*1000); // ms in the future
return _time_left(c);
}
/**
* @brief main xtimer callback function
*/
static void _timer_callback(void)
{
uint32_t next_target;
uint32_t reference;
_in_handler = 1;
DEBUG("_timer_callback() now=%" PRIu32 " (%" PRIu32 ")pleft=%" PRIu32 "\n", xtimer_now(),
_mask(xtimer_now()), _mask(0xffffffff-xtimer_now()));
if (!timer_list_head) {
DEBUG("_timer_callback(): tick\n");
/* there's no timer for this timer period,
* so this was a timer overflow callback.
*
* In this case, we advance to the next timer period.
*/
_next_period();
reference = 0;
/* make sure the timer counter also arrived
* in the next timer period */
while (_xtimer_now() == _mask(0xFFFFFFFF));
}
else {
/* we ended up in _timer_callback and there is
* a timer waiting.
*/
/* set our period reference to that timer's target time. */
reference = _mask(timer_list_head->target);
}
overflow:
/* check if next timers are close to expiring */
while (timer_list_head && (_time_left(_mask(timer_list_head->target), reference) < XTIMER_ISR_BACKOFF)) {
/* make sure we don't fire too early */
while (_time_left(_mask(timer_list_head->target), reference));
/* pick first timer in list */
xtimer_t *timer = timer_list_head;
/* advance list */
timer_list_head = timer->next;
/* make sure timer is recognized as being already fired */
timer->target = 0;
timer->long_target = 0;
/* fire timer */
_shoot(timer);
}
/* possibly executing all callbacks took enough
* time to overflow. In that case we advance to
* next timer period and check again for expired
* timers.*/
if (reference > _xtimer_now()) {
DEBUG("_timer_callback: overflowed while executing callbacks. %i\n", timer_list_head != 0);
_next_period();
reference = 0;
goto overflow;
}
if (timer_list_head) {
/* schedule callback on next timer target time */
next_target = timer_list_head->target - XTIMER_OVERHEAD;
}
else {
/* there's no timer planned for this timer period */
/* schedule callback on next overflow */
next_target = _mask(0xFFFFFFFF);
uint32_t now = _xtimer_now();
/* check for overflow again */
if (now < reference) {
_next_period();
reference = 0;
goto overflow;
}
else {
/* check if the end of this period is very soon */
if (_mask(now + XTIMER_ISR_BACKOFF) < now) {
/* spin until next period, then advance */
while (_xtimer_now() > now);
_next_period();
reference = 0;
goto overflow;
}
}
}
_in_handler = 0;
/* set low level timer */
_lltimer_set(next_target);
}
