static inline int qt_ppoll(struct pollfd *fds, nfds_t nfds, const struct timespec *timeout_ts)
{
#if QT_CONFIG(poll_ppoll) || QT_CONFIG(poll_pollts)
return ::ppoll(fds, nfds, timeout_ts, nullptr);
#elif QT_CONFIG(poll_poll)
return ::poll(fds, nfds, timespecToMillisecs(timeout_ts));
#else
return qt_poll(fds, nfds, timeout_ts);
#endif
}
static inline int qt_ppoll(struct pollfd *fds, nfds_t nfds, const struct timespec *timeout_ts)
{
#if defined(QT_HAVE_PPOLL)
return ::ppoll(fds, nfds, timeout_ts, Q_NULLPTR);
#elif defined(QT_HAVE_POLL)
return ::poll(fds, nfds, timespecToMillisecs(timeout_ts));
#else
return qt_poll(fds, nfds, timeout_ts);
#endif
}
int QEventDispatcherBlackberry::select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
timespec *timeout)
{
Q_UNUSED(nfds);
Q_D(QEventDispatcherBlackberry);
const BBScopedLoopLevelCounter bbLoopCounter(d);
BpsChannelScopeSwitcher channelSwitcher(d->bps_channel);
// prepare file sets for bps callback
d->ioData->count = 0;
d->ioData->readfds = readfds;
d->ioData->writefds = writefds;
d->ioData->exceptfds = exceptfds;
// reset all file sets
if (readfds)
FD_ZERO(readfds);
if (writefds)
FD_ZERO(writefds);
if (exceptfds)
FD_ZERO(exceptfds);
bps_event_t *event = 0;
unsigned int eventCount = 0;
// If an event handler called through filterEvent() starts a nested event loop by creating a
// new QEventLoop, we will recursively enter this function again. However, each time
// bps_get_event() is called, it destroys the last event it handed out before returning the
// next event. We don't want it to destroy the event that triggered the nested event loop,
// since there may still be more handlers that need to get that event, once the nested event
// loop is done and control returns to the outer event loop.
//
// So we move an event to a holding channel, which takes ownership of the event. Putting
// the event on our own channel allows us to manage when it is destroyed, keeping it alive
// until we know we are done with it. Each recursive call of this function needs to have
// it's own holding channel, since a channel is a queue, not a stack.
//
// However, a recursive call into this function happens very rarely compared to the many
// times this function is called. We don't want to create a holding channel for each time
// this function is called, only when it is called recursively. Thus we have the instance
// variable d->holding_channel to use in the common case. We keep track of recursive calls
// with d->loop_level. If we are in a recursive call, then we create a new holding channel
// for this run.
int holding_channel = d->holding_channel;
if ((d->loop_level > 1) &&
Q_UNLIKELY(bps_channel_create(&holding_channel, 0) != BPS_SUCCESS)) {
qWarning("QEventDispatcherBlackberry: bps_channel_create failed");
holding_channel = -1;
}
// Convert timeout to milliseconds
int timeoutTotal = -1;
if (timeout)
timeoutTotal = timespecToMillisecs(*timeout);
int timeoutLeft = timeoutTotal;
timespec startTime = qt_gettime();
// This loop exists such that we can drain the bps event queue of all native events
// more efficiently than if we were to return control to Qt after each event. This
// is important for handling touch events which can come in rapidly.
forever {
// Only emit the awake() and aboutToBlock() signals in the second iteration. For the
// first iteration, the UNIX event dispatcher will have taken care of that already.
// Also native events are actually processed one loop iteration after they were
// retrieved with bps_get_event().
// Filtering the native event should happen between the awake() and aboutToBlock()
// signal emissions. The calls awake() - filterNativeEvent() - aboutToBlock() -
// bps_get_event() need not to be interrupted by a break or return statement.
if (eventCount > 0) {
if (event) {
emit awake();
filterNativeEvent(QByteArrayLiteral("bps_event_t"), static_cast<void*>(event), 0);
emit aboutToBlock();
if (Q_LIKELY(holding_channel != -1)) {
// We are now done with this BPS event. Destroy it.
destroyHeldBpsEvent(holding_channel);
}
}
// Update the timeout
// Clock source is monotonic, so we can recalculate how much timeout is left
if (timeoutTotal != -1) {
timespec t2 = qt_gettime();
timeoutLeft = timeoutTotal
- (timespecToMillisecs(t2) - timespecToMillisecs(startTime));
if (timeoutLeft < 0)
timeoutLeft = 0;
}
timespec tnext;
if (d->timerList.timerWait(tnext)) {
int timeoutNext = timespecToMillisecs(tnext);
if (timeoutNext < timeoutLeft || timeoutTotal == -1) {
timeoutTotal = timeoutLeft = timeoutNext;
startTime = qt_gettime();
}
}
}
event = 0;
{ // We need to increase loop level in this scope,
// because bps_get_event can also invoke callbacks
QScopedLoopLevelCounter loopLevelCounter(d->threadData);
// Wait for event or file to be ready
const int result = bps_get_event(&event, timeoutLeft);
if (Q_UNLIKELY(result != BPS_SUCCESS))
qWarning("QEventDispatcherBlackberry: bps_get_event failed");
}
if (!event) // In case of !event, we break out of the loop to let Qt process the timers
break; // (since timeout has expired) and socket notifiers that are now ready.
if (bps_event_get_domain(event) == bpsUnblockDomain) {
timeoutTotal = 0; // in order to immediately drain the event queue of native events
event = 0; // (especially touch move events) we don't break out here
} else {
// Move the event to our holding channel so we can manage when it is destroyed.
if (Q_LIKELY(holding_channel != 1) &&
Q_UNLIKELY(bps_channel_push_event(holding_channel, event) != BPS_SUCCESS)) {
qWarning("QEventDispatcherBlackberry: bps_channel_push_event failed");
}
}
++eventCount;
// Make sure we are not trapped in this loop due to continuous native events
// also we cannot recalculate the timeout without a monotonic clock as the time may have changed
const unsigned int maximumEventCount = 12;
if (Q_UNLIKELY((eventCount > maximumEventCount && timeoutLeft == 0)
|| !QElapsedTimer::isMonotonic())) {
if (event) {
filterNativeEvent(QByteArrayLiteral("bps_event_t"), static_cast<void*>(event), 0);
if (Q_LIKELY(holding_channel != -1)) {
// We are now done with this BPS event. Destroy it.
destroyHeldBpsEvent(holding_channel);
}
}
break;
}
}
// If this was a recursive call into this function, a new holding channel was created for
// this run, so destroy it now.
if ((holding_channel != d->holding_channel) &&
Q_LIKELY(holding_channel != -1) &&
Q_UNLIKELY(bps_channel_destroy(holding_channel) != BPS_SUCCESS)) {
qWarning("QEventDispatcherBlackberry: bps_channel_destroy failed");
}
// the number of bits set in the file sets
return d->ioData->count;
}
