/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtCore module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 3 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL3 included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 3 requirements ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 2.0 or (at your option) the GNU General ** Public license version 3 or any later version approved by the KDE Free ** Qt Foundation. The licenses are as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-2.0.html and ** https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qabstracteventdispatcher.h" #include "qabstracteventdispatcher_p.h" #include "qabstractnativeeventfilter.h" #include "qthread.h" #include #include #include QT_BEGIN_NAMESPACE // we allow for 2^24 = 8^8 = 16777216 simultaneously running timers struct QtTimerIdFreeListConstants : public QFreeListDefaultConstants { enum { InitialNextValue = 1, BlockCount = 6 }; static const int Sizes[BlockCount]; }; enum { Offset0 = 0x00000000, Offset1 = 0x00000040, Offset2 = 0x00000100, Offset3 = 0x00001000, Offset4 = 0x00010000, Offset5 = 0x00100000, Size0 = Offset1 - Offset0, Size1 = Offset2 - Offset1, Size2 = Offset3 - Offset2, Size3 = Offset4 - Offset3, Size4 = Offset5 - Offset4, Size5 = QtTimerIdFreeListConstants::MaxIndex - Offset5 }; const int QtTimerIdFreeListConstants::Sizes[QtTimerIdFreeListConstants::BlockCount] = { Size0, Size1, Size2, Size3, Size4, Size5 }; typedef QFreeList QtTimerIdFreeList; Q_GLOBAL_STATIC(QtTimerIdFreeList, timerIdFreeList) int QAbstractEventDispatcherPrivate::allocateTimerId() { return timerIdFreeList()->next(); } void QAbstractEventDispatcherPrivate::releaseTimerId(int timerId) { // this function may be called by a global destructor after // timerIdFreeList() has been destructed if (QtTimerIdFreeList *fl = timerIdFreeList()) fl->release(timerId); } /*! \class QAbstractEventDispatcher \inmodule QtCore \brief The QAbstractEventDispatcher class provides an interface to manage Qt's event queue. \ingroup events An event dispatcher receives events from the window system and other sources. It then sends them to the QCoreApplication or QApplication instance for processing and delivery. QAbstractEventDispatcher provides fine-grained control over event delivery. For simple control of event processing use QCoreApplication::processEvents(). For finer control of the application's event loop, call instance() and call functions on the QAbstractEventDispatcher object that is returned. If you want to use your own instance of QAbstractEventDispatcher or of a QAbstractEventDispatcher subclass, you must install it with QCoreApplication::setEventDispatcher() or QThread::setEventDispatcher() \e before a default event dispatcher has been installed. The main event loop is started by calling QCoreApplication::exec(), and stopped by calling QCoreApplication::exit(). Local event loops can be created using QEventLoop. Programs that perform long operations can call processEvents() with a bitwise OR combination of various QEventLoop::ProcessEventsFlag values to control which events should be delivered. QAbstractEventDispatcher also allows the integration of an external event loop with the Qt event loop. \sa QEventLoop, QCoreApplication, QThread */ /*! Constructs a new event dispatcher with the given \a parent. */ QAbstractEventDispatcher::QAbstractEventDispatcher(QObject *parent) : QObject(*new QAbstractEventDispatcherPrivate, parent) {} /*! \internal */ QAbstractEventDispatcher::QAbstractEventDispatcher(QAbstractEventDispatcherPrivate &dd, QObject *parent) : QObject(dd, parent) {} /*! Destroys the event dispatcher. */ QAbstractEventDispatcher::~QAbstractEventDispatcher() { } /*! Returns a pointer to the event dispatcher object for the specified \a thread. If \a thread is zero, the current thread is used. If no event dispatcher exists for the specified thread, this function returns 0. \b{Note:} If Qt is built without thread support, the \a thread argument is ignored. */ QAbstractEventDispatcher *QAbstractEventDispatcher::instance(QThread *thread) { QThreadData *data = thread ? QThreadData::get2(thread) : QThreadData::current(); return data->eventDispatcher.load(); } /*! \fn bool QAbstractEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags) Processes pending events that match \a flags until there are no more events to process. Returns \c true if an event was processed; otherwise returns \c false. This function is especially useful if you have a long running operation, and want to show its progress without allowing user input by using the QEventLoop::ExcludeUserInputEvents flag. If the QEventLoop::WaitForMoreEvents flag is set in \a flags, the behavior of this function is as follows: \list \li If events are available, this function returns after processing them. \li If no events are available, this function will wait until more are available and return after processing newly available events. \endlist If the QEventLoop::WaitForMoreEvents flag is not set in \a flags, and no events are available, this function will return immediately. \b{Note:} This function does not process events continuously; it returns after all available events are processed. \sa hasPendingEvents() */ /*! \fn bool QAbstractEventDispatcher::hasPendingEvents() \deprecated Returns \c true if there is an event waiting; otherwise returns false. This function is an implementation detail for QCoreApplication::hasPendingEvents() and must not be called directly. */ /*! \fn void QAbstractEventDispatcher::registerSocketNotifier(QSocketNotifier *notifier) Registers \a notifier with the event loop. Subclasses must implement this method to tie a socket notifier into another event loop. */ /*! \fn void QAbstractEventDispatcher::unregisterSocketNotifier(QSocketNotifier *notifier) Unregisters \a notifier from the event dispatcher. Subclasses must reimplement this method to tie a socket notifier into another event loop. Reimplementations must call the base implementation. */ /*! \obsolete \fn int QAbstractEventDispatcher::registerTimer(int interval, QObject *object) Registers a timer with the specified \a interval for the given \a object and returns the timer id. */ /*! \obsolete \fn void QAbstractEventDispatcher::registerTimer(int timerId, int interval, QObject *object) Register a timer with the specified \a timerId and \a interval for the given \a object. */ /*! Registers a timer with the specified \a interval and \a timerType for the given \a object and returns the timer id. */ int QAbstractEventDispatcher::registerTimer(int interval, Qt::TimerType timerType, QObject *object) { int id = QAbstractEventDispatcherPrivate::allocateTimerId(); registerTimer(id, interval, timerType, object); return id; } /*! \fn void QAbstractEventDispatcher::registerTimer(int timerId, int interval, Qt::TimerType timerType, QObject *object) Register a timer with the specified \a timerId, \a interval, and \a timerType for the given \a object. */ /*! \fn bool QAbstractEventDispatcher::unregisterTimer(int timerId) Unregisters the timer with the given \a timerId. Returns \c true if successful; otherwise returns \c false. \sa registerTimer(), unregisterTimers() */ /*! \fn bool QAbstractEventDispatcher::unregisterTimers(QObject *object) Unregisters all the timers associated with the given \a object. Returns \c true if all timers were successful removed; otherwise returns \c false. \sa unregisterTimer(), registeredTimers() */ /*! \fn QList QAbstractEventDispatcher::registeredTimers(QObject *object) const Returns a list of registered timers for \a object. The TimerInfo struct has \c timerId, \c interval, and \c timerType members. \sa Qt::TimerType */ /*! \fn int QAbstractEventDispatcher::remainingTime(int timerId) Returns the remaining time in milliseconds with the given \a timerId. If the timer is inactive, the returned value will be -1. If the timer is overdue, the returned value will be 0. \sa Qt::TimerType */ /*! \fn void QAbstractEventDispatcher::wakeUp() \threadsafe Wakes up the event loop. \sa awake() */ /*! \fn void QAbstractEventDispatcher::interrupt() Interrupts event dispatching. The event dispatcher will return from processEvents() as soon as possible. */ /*! \fn void QAbstractEventDispatcher::flush() \deprecated Depending from the event dispatcher implementation does nothing or calls QApplication::sendPostedEvents(). */ // ### DOC: Are these called when the _application_ starts/stops or just // when the current _event loop_ starts/stops? /*! \internal */ void QAbstractEventDispatcher::startingUp() { } /*! \internal */ void QAbstractEventDispatcher::closingDown() { } /*! \class QAbstractEventDispatcher::TimerInfo \inmodule QtCore This struct represents information about a timer: \l{QAbstractEventDispatcher::TimerInfo::timerId}{timerId}, \l{QAbstractEventDispatcher::TimerInfo::interval}{interval}, and \l{QAbstractEventDispatcher::TimerInfo::timerType}{timerType}. \sa registeredTimers() */ /*! \fn QAbstractEventDispatcher::TimerInfo::TimerInfo(int timerId, int interval, Qt::TimerType timerType) Constructs a TimerInfo struct with the given \a timerId, \a interval, and \a timerType. */ /*! \variable QAbstractEventDispatcher::TimerInfo::timerId The timer's unique id. */ /*! \variable QAbstractEventDispatcher::TimerInfo::interval The timer's interval. */ /*! \variable QAbstractEventDispatcher::TimerInfo::timerType The timer's type \sa Qt::TimerType */ /*! Installs an event filter \a filterObj for all native event filters received by the application. The event filter \a filterObj receives events via its \l {QAbstractNativeEventFilter::}{nativeEventFilter()} function, which is called for all events received by all threads. The \l {QAbstractNativeEventFilter::}{nativeEventFilter()} function should return true if the event should be filtered, (in this case, stopped). It should return false to allow normal Qt processing to continue: the native event can then be translated into a QEvent and handled by the standard Qt \l{QEvent} {event} filtering, e.g. QObject::installEventFilter(). If multiple event filters are installed, the filter that was installed last is activated first. \note The filter function set here receives native messages, that is, MSG or XEvent structs. For maximum portability, you should always try to use QEvent objects and QObject::installEventFilter() whenever possible. \sa QObject::installEventFilter() \since 5.0 */ void QAbstractEventDispatcher::installNativeEventFilter(QAbstractNativeEventFilter *filterObj) { Q_D(QAbstractEventDispatcher); // clean up unused items in the list d->eventFilters.removeAll(0); d->eventFilters.removeAll(filterObj); d->eventFilters.prepend(filterObj); } /*! Removes the event filter \a filter from this object. The request is ignored if such an event filter has not been installed. All event filters for this object are automatically removed when this object is destroyed. It is always safe to remove an event filter, even during event filter filter activation (that is, even from within the \l {QAbstractNativeEventFilter::}{nativeEventFilter()} function). \sa installNativeEventFilter(), QAbstractNativeEventFilter \since 5.0 */ void QAbstractEventDispatcher::removeNativeEventFilter(QAbstractNativeEventFilter *filter) { Q_D(QAbstractEventDispatcher); for (int i = 0; i < d->eventFilters.count(); ++i) { if (d->eventFilters.at(i) == filter) { d->eventFilters[i] = 0; break; } } } /*! Sends \a message through the event filters that were set by installNativeEventFilter(). This function returns \c true as soon as an event filter returns \c true, and false otherwise to indicate that the processing of the event should continue. Subclasses of QAbstractEventDispatcher \e must call this function for \e all messages received from the system to ensure compatibility with any extensions that may be used in the application. The type of event \a eventType is specific to the platform plugin chosen at run-time, and can be used to cast message to the right type. The \a result pointer is only used on Windows, and corresponds to the LRESULT pointer. Note that the type of \a message is platform dependent. See QAbstractNativeEventFilter for details. \sa installNativeEventFilter(), QAbstractNativeEventFilter::nativeEventFilter() \since 5.0 */ bool QAbstractEventDispatcher::filterNativeEvent(const QByteArray &eventType, void *message, long *result) { Q_D(QAbstractEventDispatcher); if (!d->eventFilters.isEmpty()) { // Raise the loopLevel so that deleteLater() calls in or triggered // by event_filter() will be processed from the main event loop. QScopedScopeLevelCounter scopeLevelCounter(d->threadData); for (int i = 0; i < d->eventFilters.size(); ++i) { QAbstractNativeEventFilter *filter = d->eventFilters.at(i); if (!filter) continue; if (filter->nativeEventFilter(eventType, message, result)) return true; } } return false; } /*! \fn bool QAbstractEventDispatcher::filterEvent(void *message) \deprecated Calls filterNativeEvent() with an empty eventType and \a message. This function returns \c true as soon as an event filter returns \c true, and false otherwise to indicate that the processing of the event should continue. */ /*! \fn bool QAbstractEventDispatcher::registerEventNotifier(QWinEventNotifier *notifier); This pure virtual method exists on windows only and has to be reimplemented by a Windows specific event dispatcher implementation. \a notifier is the QWinEventNotifier instance to be registered. The method should return true if the registration of \a notifier was sucessful, otherwise false. QWinEventNotifier calls this method in it's constructor and there should never be a need to call this method directly. \sa QWinEventNotifier, unregisterEventNotifier() */ /*! \fn bool QAbstractEventDispatcher::unregisterEventNotifier(QWinEventNotifier *notifier); This pure virtual method exists on windows only and has to be reimplemented by a Windows specific event dispatcher implementation. \a notifier is the QWinEventNotifier instance to be unregistered. QWinEventNotifier calls this method in it's destructor and there should never be a need to call this method directly. \sa QWinEventNotifier, registerEventNotifier() */ /*! \fn void QAbstractEventDispatcher::awake() This signal is emitted after the event loop returns from a function that could block. \sa wakeUp(), aboutToBlock() */ /*! \fn void QAbstractEventDispatcher::aboutToBlock() This signal is emitted before the event loop calls a function that could block. \sa awake() */ QT_END_NAMESPACE #include "moc_qabstracteventdispatcher.cpp"