void sig_unmaskpendingsignal(void)
{
FAR _TCB *rtcb = (FAR _TCB*)g_readytorun.head;
sigset_t unmaskedset;
FAR sigpendq_t *pendingsig;
int signo;
/* Prohibit any context switches until we are done with this.
* We may still be performing signal operations from interrupt
* handlers, however, none of the pending signals that we
* are concerned with here should be effected.
*/
sched_lock();
/* Get the set of pending signals that were just unmasked. The
* following operation should be safe because the sigprocmask
* can only be changed on this thread of execution.
*/
unmaskedset = ~(rtcb->sigprocmask) & sig_pendingset(rtcb);
/* Loop while there are unmasked pending signals to be processed. */
while (unmaskedset != NULL_SIGNAL_SET)
{
/* Pending signals will be processed from lowest numbered signal
* to highest
*/
signo = sig_lowest(&unmaskedset);
if (signo != ERROR)
{
/* Remove the signal from the set of unmasked signals. NOTE:
* this implicitly assumes that only one instance for a given
* signal number is pending.
*/
sigdelset(&unmaskedset, signo);
/* Remove the pending signal from the list of pending signals */
if ((pendingsig = sig_removependingsignal(rtcb, signo)) != NULL)
{
/* If there is one, then process it like a normal signal */
sig_received(rtcb, &pendingsig->info);
/* Then remove it from the pending signal list */
sig_releasependingsignal(pendingsig);
}
}
}
sched_unlock();
}
int sigpending(FAR sigset_t *set)
{
FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head;
int ret = ERROR;
if (set)
{
*set = sig_pendingset(rtcb);
ret = OK;
}
return ret;
}
int sigsuspend(FAR const sigset_t *set)
{
FAR struct tcb_s *rtcb = (FAR struct tcb_s *)g_readytorun.head;
sigset_t intersection;
sigset_t saved_sigprocmask;
FAR sigpendq_t *sigpend;
irqstate_t saved_state;
int unblocksigno;
/* Several operations must be performed below: We must determine if any
* signal is pending and, if not, wait for the signal. Since signals can
* be posted from the interrupt level, there is a race condition that
* can only be eliminated by disabling interrupts!
*/
sched_lock(); /* Not necessary */
saved_state = irqsave();
/* Check if there is a pending signal corresponding to one of the
* signals that will be unblocked by the new sigprocmask.
*/
intersection = ~(*set) & sig_pendingset(rtcb);
if (intersection != NULL_SIGNAL_SET)
{
/* One or more of the signals in intersections is sufficient to cause
* us to not wait. Pick the lowest numbered signal and mark it not
* pending.
*/
unblocksigno = sig_lowest(&intersection);
sigpend = sig_removependingsignal(rtcb, unblocksigno);
ASSERT(sigpend);
sig_releasependingsignal(sigpend);
irqrestore(saved_state);
}
else
{
/* Its time to wait. Save a copy of the old sigprocmask and install
* the new (temporary) sigprocmask
*/
saved_sigprocmask = rtcb->sigprocmask;
rtcb->sigprocmask = *set;
rtcb->sigwaitmask = NULL_SIGNAL_SET;
/* And wait until one of the unblocked signals is posted */
up_block_task(rtcb, TSTATE_WAIT_SIG);
/* We are running again, restore the original sigprocmask */
rtcb->sigprocmask = saved_sigprocmask;
irqrestore(saved_state);
/* Now, handle the (rare?) case where (a) a blocked signal was received
* while the task was suspended but (b) restoring the original
* sigprocmask will unblock the signal.
*/
sig_unmaskpendingsignal();
}
sched_unlock();
return ERROR;
}
int sigtimedwait(FAR const sigset_t *set, FAR struct siginfo *info,
FAR const struct timespec *timeout)
{
FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head;
sigset_t intersection;
FAR sigpendq_t *sigpend;
irqstate_t saved_state;
int32_t waitticks;
int ret = ERROR;
DEBUGASSERT(rtcb->waitdog == NULL);
sched_lock(); /* Not necessary */
/* Several operations must be performed below: We must determine if any
* signal is pending and, if not, wait for the signal. Since signals can
* be posted from the interrupt level, there is a race condition that
* can only be eliminated by disabling interrupts!
*/
saved_state = irqsave();
/* Check if there is a pending signal corresponding to one of the
* signals in the pending signal set argument.
*/
intersection = *set & sig_pendingset(rtcb);
if (intersection != NULL_SIGNAL_SET)
{
/* One or more of the signals in intersections is sufficient to cause
* us to not wait. Pick the lowest numbered signal and mark it not
* pending.
*/
sigpend = sig_removependingsignal(rtcb, sig_lowest(&intersection));
ASSERT(sigpend);
/* Return the signal info to the caller if so requested */
if (info)
{
memcpy(info, &sigpend->info, sizeof(struct siginfo));
}
/* Then dispose of the pending signal structure properly */
sig_releasependingsignal(sigpend);
irqrestore(saved_state);
/* The return value is the number of the signal that awakened us */
ret = sigpend->info.si_signo;
}
/* We will have to wait for a signal to be posted to this task. */
else
{
/* Save the set of pending signals to wait for */
rtcb->sigwaitmask = *set;
/* Check if we should wait for the timeout */
if (timeout)
{
/* Convert the timespec to system clock ticks, making sure that
* the resulting delay is greater than or equal to the requested
* time in nanoseconds.
*/
#ifdef CONFIG_HAVE_LONG_LONG
uint64_t waitticks64 = ((uint64_t)timeout->tv_sec * NSEC_PER_SEC +
(uint64_t)timeout->tv_nsec + NSEC_PER_TICK - 1) /
NSEC_PER_TICK;
DEBUGASSERT(waitticks64 <= UINT32_MAX);
waitticks = (uint32_t)waitticks64;
#else
uint32_t waitmsec;
DEBUGASSERT(timeout->tv_sec < UINT32_MAX / MSEC_PER_SEC);
waitmsec = timeout->tv_sec * MSEC_PER_SEC +
(timeout->tv_nsec + NSEC_PER_MSEC - 1) / NSEC_PER_MSEC;
waitticks = MSEC2TICK(waitmsec);
#endif
/* Create a watchdog */
rtcb->waitdog = wd_create();
DEBUGASSERT(rtcb->waitdog);
if (rtcb->waitdog)
{
/* This little bit of nonsense is necessary for some
* processors where sizeof(pointer) < sizeof(uint32_t).
* see wdog.h.
*/
wdparm_t wdparm;
wdparm.pvarg = (FAR void *)rtcb;
/* Start the watchdog */
wd_start(rtcb->waitdog, waitticks, (wdentry_t)sig_timeout, 1,
wdparm.dwarg);
/* Now wait for either the signal or the watchdog */
up_block_task(rtcb, TSTATE_WAIT_SIG);
/* We no longer need the watchdog */
wd_delete(rtcb->waitdog);
rtcb->waitdog = NULL;
}
/* REVISIT: And do what if there are no watchdog timers? The wait
* will fail and we will return something bogus.
*/
}
/* No timeout, just wait */
else
{
/* And wait until one of the unblocked signals is posted */
up_block_task(rtcb, TSTATE_WAIT_SIG);
}
/* We are running again, clear the sigwaitmask */
rtcb->sigwaitmask = NULL_SIGNAL_SET;
/* When we awaken, the cause will be in the TCB. Get the signal number
* or timeout) that awakened us.
*/
if (GOOD_SIGNO(rtcb->sigunbinfo.si_signo))
{
/* We were awakened by a signal... but is it one of the signals that
* we were waiting for?
*/
if (sigismember(set, rtcb->sigunbinfo.si_signo))
{
/* Yes.. the return value is the number of the signal that
* awakened us.
*/
ret = rtcb->sigunbinfo.si_signo;
}
else
{
/* No... then set EINTR and report an error */
set_errno(EINTR);
ret = ERROR;
}
}
else
{
/* Otherwise, we must have been awakened by the timeout. Set EGAIN
* and return an error.
*/
DEBUGASSERT(rtcb->sigunbinfo.si_signo == SIG_WAIT_TIMEOUT);
set_errno(EAGAIN);
ret = ERROR;
}
/* Return the signal info to the caller if so requested */
if (info)
{
memcpy(info, &rtcb->sigunbinfo, sizeof(struct siginfo));
}
irqrestore(saved_state);
}
sched_unlock();
return ret;
}
