src/gui/kernel/qeventdispatcher_mac.mm
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gui/kernel/qeventdispatcher_mac.mm	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,1085 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/****************************************************************************
+**
+** Copyright (c) 2007-2008, Apple, Inc.
+**
+** All rights reserved.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+**
+**   * Redistributions of source code must retain the above copyright notice,
+**     this list of conditions and the following disclaimer.
+**
+**   * Redistributions in binary form must reproduce the above copyright notice,
+**     this list of conditions and the following disclaimer in the documentation
+**     and/or other materials provided with the distribution.
+**
+**   * Neither the name of Apple, Inc. nor the names of its contributors
+**     may be used to endorse or promote products derived from this software
+**     without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+** EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+** PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+** LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+** NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+** SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**
+****************************************************************************/
+
+#include "qplatformdefs.h"
+#include "private/qt_mac_p.h"
+#include "qeventdispatcher_mac_p.h"
+#include "qapplication.h"
+#include "qevent.h"
+#include "qdialog.h"
+#include "qhash.h"
+#include "qsocketnotifier.h"
+#include "private/qwidget_p.h"
+#include "private/qthread_p.h"
+#include "private/qapplication_p.h"
+
+#include <private/qcocoaapplication_mac_p.h>
+#include "private/qt_cocoa_helpers_mac_p.h"
+
+#ifndef QT_NO_THREAD
+#  include "qmutex.h"
+
+QT_BEGIN_NAMESPACE
+
+QT_USE_NAMESPACE
+#endif
+
+/*****************************************************************************
+  Externals
+ *****************************************************************************/
+extern void qt_event_request_timer(MacTimerInfo *); //qapplication_mac.cpp
+extern MacTimerInfo *qt_event_get_timer(EventRef); //qapplication_mac.cpp
+extern void qt_event_request_select(QEventDispatcherMac *); //qapplication_mac.cpp
+extern void qt_event_request_updates(); //qapplication_mac.cpp
+extern OSWindowRef qt_mac_window_for(const QWidget *); //qwidget_mac.cpp
+extern bool qt_is_gui_used; //qapplication.cpp
+extern bool qt_sendSpontaneousEvent(QObject*, QEvent*); // qapplication.cpp
+extern bool qt_mac_is_macsheet(const QWidget *); //qwidget_mac.cpp
+
+static inline CFRunLoopRef mainRunLoop()
+{
+#ifndef QT_MAC_USE_COCOA
+    return reinterpret_cast<CFRunLoopRef>(const_cast<void *>(GetCFRunLoopFromEventLoop(GetMainEventLoop())));
+#else
+    return CFRunLoopGetMain();
+#endif
+}
+
+/*****************************************************************************
+  Timers stuff
+ *****************************************************************************/
+
+/* timer call back */
+void QEventDispatcherMacPrivate::activateTimer(CFRunLoopTimerRef, void *info)
+{
+    int timerID =
+#ifdef Q_OS_MAC64
+    qint64(info);
+#else
+    int(info);
+#endif
+
+    MacTimerInfo *tmr;
+    tmr = macTimerHash.value(timerID);
+    if (tmr == 0 || tmr->pending == true)
+        return; // Can't send another timer event if it's pending.
+
+
+    if (blockSendPostedEvents) {
+        QCoreApplication::postEvent(tmr->obj, new QTimerEvent(tmr->id));
+    } else {
+        tmr->pending = true;
+        QTimerEvent e(tmr->id);
+        qt_sendSpontaneousEvent(tmr->obj, &e);
+        // Get the value again in case the timer gets unregistered during the sendEvent.
+        tmr = macTimerHash.value(timerID);
+        if (tmr != 0)
+            tmr->pending = false;
+    }
+
+}
+
+void QEventDispatcherMac::registerTimer(int timerId, int interval, QObject *obj)
+{
+#ifndef QT_NO_DEBUG
+    if (timerId < 1 || interval < 0 || !obj) {
+        qWarning("QEventDispatcherMac::registerTimer: invalid arguments");
+        return;
+    } else if (obj->thread() != thread() || thread() != QThread::currentThread()) {
+        qWarning("QObject::startTimer: timers cannot be started from another thread");
+        return;
+    }
+#endif
+
+    MacTimerInfo *t = new MacTimerInfo();
+    t->id = timerId;
+    t->interval = interval;
+    t->obj = obj;
+    t->runLoopTimer = 0;
+    t->pending = false;
+
+    CFAbsoluteTime fireDate = CFAbsoluteTimeGetCurrent();
+    CFTimeInterval cfinterval = qMax(CFTimeInterval(interval) / 1000, 0.0000001);
+    fireDate += cfinterval;
+    QEventDispatcherMacPrivate::macTimerHash.insert(timerId, t);
+    CFRunLoopTimerContext info = { 0, (void *)timerId, 0, 0, 0 };
+    t->runLoopTimer = CFRunLoopTimerCreate(0, fireDate, cfinterval, 0, 0,
+                                           QEventDispatcherMacPrivate::activateTimer, &info);
+    if (t->runLoopTimer == 0) {
+        qFatal("QEventDispatcherMac::registerTimer: Cannot create timer");
+    }
+    CFRunLoopAddTimer(mainRunLoop(), t->runLoopTimer, kCFRunLoopCommonModes);
+}
+
+bool QEventDispatcherMac::unregisterTimer(int identifier)
+{
+#ifndef QT_NO_DEBUG
+    if (identifier < 1) {
+        qWarning("QEventDispatcherMac::unregisterTimer: invalid argument");
+        return false;
+    } else if (thread() != QThread::currentThread()) {
+        qWarning("QObject::killTimer: timers cannot be stopped from another thread");
+        return false;
+    }
+#endif
+    if (identifier <= 0)
+        return false;                                // not init'd or invalid timer
+
+    MacTimerInfo *timerInfo = QEventDispatcherMacPrivate::macTimerHash.take(identifier);
+    if (timerInfo == 0)
+        return false;
+
+    if (!QObjectPrivate::get(timerInfo->obj)->inThreadChangeEvent)
+        QAbstractEventDispatcherPrivate::releaseTimerId(identifier);
+    CFRunLoopTimerInvalidate(timerInfo->runLoopTimer);
+    CFRelease(timerInfo->runLoopTimer);
+    delete timerInfo;
+
+    return true;
+}
+
+bool QEventDispatcherMac::unregisterTimers(QObject *obj)
+{
+#ifndef QT_NO_DEBUG
+    if (!obj) {
+        qWarning("QEventDispatcherMac::unregisterTimers: invalid argument");
+        return false;
+    } else if (obj->thread() != thread() || thread() != QThread::currentThread()) {
+        qWarning("QObject::killTimers: timers cannot be stopped from another thread");
+        return false;
+    }
+#endif
+
+    MacTimerHash::iterator it = QEventDispatcherMacPrivate::macTimerHash.begin();
+    while (it != QEventDispatcherMacPrivate::macTimerHash.end()) {
+        MacTimerInfo *timerInfo = it.value();
+        if (timerInfo->obj != obj) {
+            ++it;
+        } else {
+            if (!QObjectPrivate::get(timerInfo->obj)->inThreadChangeEvent)
+                QAbstractEventDispatcherPrivate::releaseTimerId(timerInfo->id);
+            CFRunLoopTimerInvalidate(timerInfo->runLoopTimer);
+            CFRelease(timerInfo->runLoopTimer);
+            delete timerInfo;
+            it = QEventDispatcherMacPrivate::macTimerHash.erase(it);
+        }
+    }
+    return true;
+}
+
+QList<QEventDispatcherMac::TimerInfo>
+QEventDispatcherMac::registeredTimers(QObject *object) const
+{
+    if (!object) {
+        qWarning("QEventDispatcherMac:registeredTimers: invalid argument");
+        return QList<TimerInfo>();
+    }
+
+    QList<TimerInfo> list;
+
+    MacTimerHash::const_iterator it = QEventDispatcherMacPrivate::macTimerHash.constBegin();
+    while (it != QEventDispatcherMacPrivate::macTimerHash.constEnd()) {
+        MacTimerInfo *t = it.value();
+        if (t->obj == object)
+            list << TimerInfo(t->id, t->interval);
+        ++it;
+    }
+    return list;
+}
+
+/**************************************************************************
+    Socket Notifiers
+ *************************************************************************/
+void qt_mac_socket_callback(CFSocketRef s, CFSocketCallBackType callbackType, CFDataRef,
+                            const void *,  void *info) {
+    QEventDispatcherMacPrivate *const eventDispatcher
+                                    = static_cast<QEventDispatcherMacPrivate *>(info);
+    int nativeSocket = CFSocketGetNative(s);
+    MacSocketInfo *socketInfo = eventDispatcher->macSockets.value(nativeSocket);
+    QEvent notifierEvent(QEvent::SockAct);
+
+    // There is a race condition that happen where we disable the notifier and
+    // the kernel still has a notification to pass on. We then get this
+    // notification after we've successfully disabled the CFSocket, but our Qt
+    // notifier is now gone. The upshot is we have to check the notifier
+    // everytime.
+    if (callbackType == kCFSocketReadCallBack) {
+        if (socketInfo->readNotifier)
+            QApplication::sendEvent(socketInfo->readNotifier, &notifierEvent);
+    } else if (callbackType == kCFSocketWriteCallBack) {
+        if (socketInfo->writeNotifier)
+            QApplication::sendEvent(socketInfo->writeNotifier, &notifierEvent);
+    }
+}
+
+/*
+    Adds a loop source for the given socket to the current run loop.
+*/
+CFRunLoopSourceRef qt_mac_add_socket_to_runloop(const CFSocketRef socket)
+{
+    CFRunLoopSourceRef loopSource = CFSocketCreateRunLoopSource(kCFAllocatorDefault, socket, 0);
+    if (!loopSource)
+        return 0;
+
+    CFRunLoopAddSource(mainRunLoop(), loopSource, kCFRunLoopCommonModes);
+    return loopSource;
+}
+
+/*
+    Removes the loop source for the given socket from the current run loop.
+*/
+void qt_mac_remove_socket_from_runloop(const CFSocketRef socket, CFRunLoopSourceRef runloop)
+{
+    Q_ASSERT(runloop);
+    CFRunLoopRemoveSource(mainRunLoop(), runloop, kCFRunLoopCommonModes);
+    CFSocketDisableCallBacks(socket, kCFSocketReadCallBack);
+    CFSocketDisableCallBacks(socket, kCFSocketWriteCallBack);
+    CFRunLoopSourceInvalidate(runloop);
+}
+
+/*
+    Register a QSocketNotifier with the mac event system by creating a CFSocket with
+    with a read/write callback.
+
+    Qt has separate socket notifiers for reading and writing, but on the mac there is
+    a limitation of one CFSocket object for each native socket.
+*/
+void QEventDispatcherMac::registerSocketNotifier(QSocketNotifier *notifier)
+{
+    Q_ASSERT(notifier);
+    int nativeSocket = notifier->socket();
+    int type = notifier->type();
+#ifndef QT_NO_DEBUG
+    if (nativeSocket < 0 || nativeSocket > FD_SETSIZE) {
+        qWarning("QSocketNotifier: Internal error");
+        return;
+    } else if (notifier->thread() != thread()
+               || thread() != QThread::currentThread()) {
+        qWarning("QSocketNotifier: socket notifiers cannot be enabled from another thread");
+        return;
+    }
+#endif
+
+    Q_D(QEventDispatcherMac);
+
+    if (type == QSocketNotifier::Exception) {
+        qWarning("QSocketNotifier::Exception is not supported on Mac OS X");
+        return;
+    }
+
+    // Check if we have a CFSocket for the native socket, create one if not.
+    MacSocketInfo *socketInfo = d->macSockets.value(nativeSocket);
+    if (!socketInfo) {
+        socketInfo = new MacSocketInfo();
+
+        // Create CFSocket, specify that we want both read and write callbacks (the callbacks
+        // are enabled/disabled later on).
+        const int callbackTypes = kCFSocketReadCallBack | kCFSocketWriteCallBack;
+        CFSocketContext context = {0, d, 0, 0, 0};
+        socketInfo->socket = CFSocketCreateWithNative(kCFAllocatorDefault, nativeSocket, callbackTypes, qt_mac_socket_callback, &context);
+        if (CFSocketIsValid(socketInfo->socket) == false) {
+            qWarning("QEventDispatcherMac::registerSocketNotifier: Failed to create CFSocket");
+            return;
+        }
+
+        CFOptionFlags flags = CFSocketGetSocketFlags(socketInfo->socket);
+        flags |= kCFSocketAutomaticallyReenableWriteCallBack; //QSocketNotifier stays enabled after a write
+        flags &= ~kCFSocketCloseOnInvalidate; //QSocketNotifier doesn't close the socket upon destruction/invalidation
+        CFSocketSetSocketFlags(socketInfo->socket, flags);
+
+        // Add CFSocket to runloop.
+        if(!(socketInfo->runloop = qt_mac_add_socket_to_runloop(socketInfo->socket))) {
+            qWarning("QEventDispatcherMac::registerSocketNotifier: Failed to add CFSocket to runloop");
+            CFSocketInvalidate(socketInfo->socket);
+            CFRelease(socketInfo->socket);
+            return;
+        }
+
+        // Disable both callback types by default. This must be done after
+        // we add the CFSocket to the runloop, or else these calls will have
+        // no effect.
+        CFSocketDisableCallBacks(socketInfo->socket, kCFSocketReadCallBack);
+        CFSocketDisableCallBacks(socketInfo->socket, kCFSocketWriteCallBack);
+
+        d->macSockets.insert(nativeSocket, socketInfo);
+    }
+
+    // Increment read/write counters and select enable callbacks if necessary.
+    if (type == QSocketNotifier::Read) {
+        Q_ASSERT(socketInfo->readNotifier == 0);
+        socketInfo->readNotifier = notifier;
+        CFSocketEnableCallBacks(socketInfo->socket, kCFSocketReadCallBack);
+    } else if (type == QSocketNotifier::Write) {
+        Q_ASSERT(socketInfo->writeNotifier == 0);
+        socketInfo->writeNotifier = notifier;
+        CFSocketEnableCallBacks(socketInfo->socket, kCFSocketWriteCallBack);
+    }
+}
+
+/*
+    Unregister QSocketNotifer. The CFSocket correspoding to this notifier is
+    removed from the runloop of this is the last notifier that users
+    that CFSocket.
+*/
+void QEventDispatcherMac::unregisterSocketNotifier(QSocketNotifier *notifier)
+{
+    Q_ASSERT(notifier);
+    int nativeSocket = notifier->socket();
+    int type = notifier->type();
+#ifndef QT_NO_DEBUG
+    if (nativeSocket < 0 || nativeSocket > FD_SETSIZE) {
+        qWarning("QSocketNotifier: Internal error");
+        return;
+    } else if (notifier->thread() != thread() || thread() != QThread::currentThread()) {
+        qWarning("QSocketNotifier: socket notifiers cannot be disabled from another thread");
+        return;
+    }
+#endif
+
+    Q_D(QEventDispatcherMac);
+
+    if (type == QSocketNotifier::Exception) {
+        qWarning("QSocketNotifier::Exception is not supported on Mac OS X");
+        return;
+    }
+    MacSocketInfo *socketInfo = d->macSockets.value(nativeSocket);
+    if (!socketInfo) {
+        qWarning("QEventDispatcherMac::unregisterSocketNotifier: Tried to unregister a not registered notifier");
+        return;
+    }
+
+    // Decrement read/write counters and disable callbacks if necessary.
+    if (type == QSocketNotifier::Read) {
+        Q_ASSERT(notifier == socketInfo->readNotifier);
+        socketInfo->readNotifier = 0;
+        CFSocketDisableCallBacks(socketInfo->socket, kCFSocketReadCallBack);
+    } else if (type == QSocketNotifier::Write) {
+        Q_ASSERT(notifier == socketInfo->writeNotifier);
+        socketInfo->writeNotifier = 0;
+        CFSocketDisableCallBacks(socketInfo->socket, kCFSocketWriteCallBack);
+    }
+
+    // Remove CFSocket from runloop if this was the last QSocketNotifier.
+    if (socketInfo->readNotifier == 0 && socketInfo->writeNotifier == 0) {
+        if (CFSocketIsValid(socketInfo->socket))
+            qt_mac_remove_socket_from_runloop(socketInfo->socket, socketInfo->runloop);
+        CFRunLoopSourceInvalidate(socketInfo->runloop);
+        CFRelease(socketInfo->runloop);
+        CFSocketInvalidate(socketInfo->socket);
+        CFRelease(socketInfo->socket);
+        delete socketInfo;
+        d->macSockets.remove(nativeSocket);
+    }
+}
+
+bool QEventDispatcherMac::hasPendingEvents()
+{
+    extern uint qGlobalPostedEventsCount();
+    return qGlobalPostedEventsCount() || (qt_is_gui_used && GetNumEventsInQueue(GetMainEventQueue()));
+}
+
+
+static bool qt_mac_send_event(QEventLoop::ProcessEventsFlags, OSEventRef event, OSWindowRef pt)
+{
+#ifndef QT_MAC_USE_COCOA
+    if(pt && SendEventToWindow(event, pt) != eventNotHandledErr)
+        return true;
+    return !SendEventToEventTarget(event, GetEventDispatcherTarget());
+#else // QT_MAC_USE_COCOA
+    if (pt)
+        [pt sendEvent:event];
+    else
+        [NSApp sendEvent:event];
+    return true;
+#endif
+}
+
+#ifdef QT_MAC_USE_COCOA
+static bool IsMouseOrKeyEvent( NSEvent* event )
+{
+    bool    result    = false;
+    
+    switch( [event type] )
+    {
+        case NSLeftMouseDown:              
+        case NSLeftMouseUp:      
+        case NSRightMouseDown:   
+        case NSRightMouseUp:     
+        case NSMouseMoved:                // ??
+        case NSLeftMouseDragged: 
+        case NSRightMouseDragged:
+        case NSMouseEntered:     
+        case NSMouseExited:      
+        case NSKeyDown:          
+        case NSKeyUp:            
+        case NSFlagsChanged:            // key modifiers changed?
+        case NSCursorUpdate:            // ??
+        case NSScrollWheel:      
+        case NSTabletPoint:      
+        case NSTabletProximity:  
+        case NSOtherMouseDown:   
+        case NSOtherMouseUp:     
+        case NSOtherMouseDragged:
+            result    = true;
+        break;
+
+        default:
+        break;
+    }
+    return result;
+}
+#endif
+
+static inline void qt_mac_waitForMoreEvents()
+{
+#ifndef QT_MAC_USE_COCOA
+    while (CFRunLoopRunInMode(kCFRunLoopDefaultMode, 1.0e20, true) == kCFRunLoopRunTimedOut) ;
+#else
+    // If no event exist in the cocoa event que, wait
+    // (and free up cpu time) until at least one event occur.
+    // This implementation is a bit on the edge, but seems to
+    // work fine:
+    NSEvent* event = [NSApp nextEventMatchingMask:NSAnyEventMask
+        untilDate:[NSDate distantFuture]
+        inMode:NSDefaultRunLoopMode
+        dequeue:YES];
+    if (event)
+        [NSApp postEvent:event atStart:YES];
+#endif
+}
+
+#ifdef QT_MAC_USE_COCOA
+static inline void qt_mac_waitForMoreModalSessionEvents()
+{
+    // If no event exist in the cocoa event que, wait
+    // (and free up cpu time) until at least one event occur.
+    // This implementation is a bit on the edge, but seems to
+    // work fine:
+    NSEvent* event = [NSApp nextEventMatchingMask:NSAnyEventMask
+        untilDate:[NSDate distantFuture]
+        inMode:NSModalPanelRunLoopMode
+        dequeue:YES];
+    if (event)
+        [NSApp postEvent:event atStart:YES];
+}
+#endif
+
+bool QEventDispatcherMac::processEvents(QEventLoop::ProcessEventsFlags flags)
+{
+    Q_D(QEventDispatcherMac);
+    d->interrupt = false;
+    // In case we end up recursing while we now process events, make sure
+    // that we send remaining posted Qt events before this call returns:
+    wakeUp();
+    emit awake();
+
+    bool retVal = false;
+    forever {
+        if (d->interrupt)
+            break;
+
+#ifdef QT_MAC_USE_COCOA
+        QMacCocoaAutoReleasePool pool;
+        NSEvent* event = 0;
+
+        // If Qt is used as a plugin, or just added into a native cocoa
+        // application, we should not run or stop NSApplication;
+        // This will be done from outside Qt.
+        // And if processEvents is called manually (rather than from QEventLoop), we
+        // cannot enter a tight loop and block the call, but instead return after one flush:
+        bool canExec_3rdParty = d->nsAppRunCalledByQt || ![NSApp isRunning];
+        bool canExec_Qt = flags & QEventLoop::DialogExec || flags & QEventLoop::EventLoopExec;
+
+        if (canExec_Qt && canExec_3rdParty) {
+            // We can use exec-mode, meaning that we can stay in a tight loop until
+            // interrupted. This is mostly an optimization, but it also allow us
+            // to use [NSApp run], which is the recommended way of running applications
+            // in cocoa. [NSApp run] should be called at least once for any cocoa app.
+            if (NSModalSession session = d->currentModalSession()) {
+                QBoolBlocker execGuard(d->currentExecIsNSAppRun, false);
+                while (!d->interrupt && [NSApp runModalSession:session] == NSRunContinuesResponse)
+                    qt_mac_waitForMoreModalSessionEvents();
+            } else {
+                d->nsAppRunCalledByQt = true;
+                QBoolBlocker execGuard(d->currentExecIsNSAppRun, true);
+                [NSApp run];
+            }
+            retVal = true;
+        } else do {
+            // INVARIANT: We cannot block the thread (and run in a tight loop).
+            // Instead we will process all current pending events and return.
+            bool mustRelease = false;
+
+            if (!(flags & QEventLoop::ExcludeUserInputEvents) && !d->queuedUserInputEvents.isEmpty()) {
+                // Process a pending user input event
+                mustRelease = true;
+                event = static_cast<NSEvent *>(d->queuedUserInputEvents.takeFirst());
+            } else {
+                if (NSModalSession session = d->currentModalSession()) {
+                    if (flags & QEventLoop::WaitForMoreEvents)
+                        qt_mac_waitForMoreModalSessionEvents();
+                    [NSApp runModalSession:session];
+                    retVal = true;
+                    break;
+                } else {
+                    event = [NSApp nextEventMatchingMask:NSAnyEventMask
+                        untilDate:nil
+                        inMode:NSDefaultRunLoopMode
+                        dequeue: YES];
+
+                    if (event != nil) {
+                        if (flags & QEventLoop::ExcludeUserInputEvents) {
+                            if (IsMouseOrKeyEvent(event)) {
+                                // retain event here?
+                                [event retain];
+                                d->queuedUserInputEvents.append(event);
+                                continue;
+                            }
+                        }
+                    }
+                }
+            }
+            if (event) {
+                if (!filterEvent(event) && qt_mac_send_event(flags, event, 0))
+                    retVal = true;
+                if (mustRelease)
+                    [event release];
+            }
+        } while(!d->interrupt && event != nil);
+
+#else
+        do {
+            EventRef event;
+            if (!(flags & QEventLoop::ExcludeUserInputEvents)
+                    && !d->queuedUserInputEvents.isEmpty()) {
+                // process a pending user input event
+                event = static_cast<EventRef>(d->queuedUserInputEvents.takeFirst());
+            } else {
+                OSStatus err = ReceiveNextEvent(0,0, kEventDurationNoWait, true, &event);
+                if(err != noErr)
+                    continue;
+                // else
+                if (flags & QEventLoop::ExcludeUserInputEvents) {
+                    UInt32 ekind = GetEventKind(event),
+                           eclass = GetEventClass(event);
+                    switch(eclass) {
+                        case kEventClassQt:
+                            if(ekind != kEventQtRequestContext)
+                                break;
+                            // fall through
+                        case kEventClassMouse:
+                        case kEventClassKeyboard:
+                            d->queuedUserInputEvents.append(event);
+                            continue;
+                    }
+                }
+            }
+
+            if (!filterEvent(&event) && qt_mac_send_event(flags, event, 0))
+                retVal = true;
+            ReleaseEvent(event);
+        } while(!d->interrupt && GetNumEventsInQueue(GetMainEventQueue()) > 0);
+
+#endif
+
+        bool canWait = (d->threadData->canWait
+                && !retVal
+                && !d->interrupt
+                && (flags & QEventLoop::WaitForMoreEvents));
+        if (canWait) {
+            // INVARIANT: We haven't processed any events yet. And we're told
+            // to stay inside this function until at least one event is processed.
+            qt_mac_waitForMoreEvents();
+            flags &= ~QEventLoop::WaitForMoreEvents;
+        } else {
+            // Done with event processing for now.
+            // Leave the function:
+            break;
+        }
+    }
+
+#ifdef QT_MAC_USE_COCOA
+    // In case we _now_ process events using [NSApp run], we need to stop it to
+    // ensure that:
+    //    1. the QEventLoop that called us is still executing, or
+    //    2. we have a modal session that needs to be spun instead.
+    // In case this is a plain call to processEvents (perhaps from a loop) 
+    // from the application (rather than from a QEventLoop), we delay the
+    // interrupting until we/ actually enter a lower loop level (hence the
+    // deffered delete of the object below):
+    QtMacInterruptDispatcherHelp::interruptLater();
+#endif
+
+    if (d->interrupt) {
+        // We should continue to leave all recursion to processEvents until
+        // processEvents is called again (e.g. from a QEventLoop that 
+        // was not yet told to quit:
+        interrupt();
+    }
+
+    return retVal;
+}
+
+void QEventDispatcherMac::wakeUp()
+{
+    Q_D(QEventDispatcherMac);
+    d->serialNumber.ref();
+    CFRunLoopSourceSignal(d->postedEventsSource);
+    CFRunLoopWakeUp(mainRunLoop());
+}
+
+void QEventDispatcherMac::flush()
+{
+    if(qApp) {
+        QWidgetList tlws = QApplication::topLevelWidgets();
+        for(int i = 0; i < tlws.size(); i++) {
+            QWidget *tlw = tlws.at(i);
+            if(tlw->isVisible())
+                macWindowFlush(qt_mac_window_for(tlw));
+        }
+    }
+}
+
+/*****************************************************************************
+  QEventDispatcherMac Implementation
+ *****************************************************************************/
+MacTimerHash QEventDispatcherMacPrivate::macTimerHash;
+bool QEventDispatcherMacPrivate::blockSendPostedEvents = false;
+
+#ifdef QT_MAC_USE_COCOA
+QStack<QCocoaModalSessionInfo> QEventDispatcherMacPrivate::cocoaModalSessionStack;
+bool QEventDispatcherMacPrivate::currentExecIsNSAppRun = false;
+bool QEventDispatcherMacPrivate::nsAppRunCalledByQt = false;
+NSModalSession QEventDispatcherMacPrivate::currentModalSessionCached = 0;
+
+int QEventDispatcherMacPrivate::activeModalSessionCount()
+{
+    // Returns the number of modal sessions created
+    // (and not just pushed onto the stack, pending to be created)
+    int count = 0;
+    for (int i=cocoaModalSessionStack.size()-1; i>=0; --i) {
+        QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
+        if (info.session)
+            ++count;
+    }
+    return count;
+}
+
+void QEventDispatcherMacPrivate::temporarilyStopAllModalSessions()
+{
+    // Stop all created modal session, and as such, make then
+    // pending again. The next call to currentModalSession will
+    // recreate the session on top again:
+    int stackSize = cocoaModalSessionStack.size();
+    for (int i=stackSize-1; i>=0; --i) {
+        QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
+        if (info.session) {
+            [NSApp endModalSession:info.session];
+            info.session = 0;
+        }
+    }
+    currentModalSessionCached = 0;
+}
+
+NSModalSession QEventDispatcherMacPrivate::currentModalSession()
+{
+    // If we have one or more modal windows, this function will create
+    // a session for each of those, and return the one for the top.
+    if (currentModalSessionCached)
+        return currentModalSessionCached;
+
+    if (cocoaModalSessionStack.isEmpty())
+        return 0;
+
+    // Since this code will end up calling our Qt event handler
+    // (also from beginModalSessionForWindow), we need to block
+    // that to avoid side effects of events beeing delivered:
+    QBoolBlocker block(blockSendPostedEvents, true);
+
+    if (![NSApp isRunning]) {
+        // Sadly, we need to introduce this little event flush
+        // to stop dialogs from blinking/poping in front if a 
+        // modal session restart was needed:
+        while (NSEvent *event = [NSApp nextEventMatchingMask:0
+                untilDate:nil
+                inMode:NSDefaultRunLoopMode
+                dequeue: YES]) {
+            qt_mac_send_event(0, event, 0);
+        }
+    }
+
+    int sessionCount = cocoaModalSessionStack.size();
+    for (int i=0; i<sessionCount; ++i) {
+        QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
+        if (!info.widget)
+            continue;
+        if (info.widget->testAttribute(Qt::WA_DontShowOnScreen))
+            continue;
+        if (!info.session) {
+            QMacCocoaAutoReleasePool pool;
+            NSWindow *window = qt_mac_window_for(info.widget);
+            if (!window)
+                continue;
+            info.session = [NSApp beginModalSessionForWindow:window];
+        }
+        currentModalSessionCached = info.session;
+    }
+
+    return currentModalSessionCached;
+}
+
+static void setChildrenWorksWhenModal(QWidget *widget, bool worksWhenModal)
+{
+    // For NSPanels (but not NSWindows, sadly), we can set the flag
+    // worksWhenModal, so that they are active even when they are not modal. 
+    QList<QDialog *> dialogs = widget->findChildren<QDialog *>();
+    for (int i=0; i<dialogs.size(); ++i){
+        NSWindow *window = qt_mac_window_for(dialogs[i]);
+        if (window && [window isKindOfClass:[NSPanel class]]) {
+            [static_cast<NSPanel *>(window) setWorksWhenModal:worksWhenModal];
+            if (worksWhenModal && dialogs[i]->isVisible()){
+                [window orderFront:window];
+            }
+        }
+    }
+}
+
+void QEventDispatcherMacPrivate::updateChildrenWorksWhenModal()
+{
+    // Make the dialog children of the widget
+    // active. And make the dialog children of
+    // the previous modal dialog unactive again:
+    int size = cocoaModalSessionStack.size();
+    if (size > 0){
+        if (QWidget *prevModal = cocoaModalSessionStack[size-1].widget)
+            setChildrenWorksWhenModal(prevModal, true);
+        if (size > 1){
+            if (QWidget *prevModal = cocoaModalSessionStack[size-2].widget)
+                setChildrenWorksWhenModal(prevModal, false);
+        }
+    }
+}
+
+void QEventDispatcherMacPrivate::beginModalSession(QWidget *widget)
+{
+    // Add a new, empty (null), NSModalSession to the stack.
+    // It will become active the next time QEventDispatcher::processEvents is called.
+    // A QCocoaModalSessionInfo is considered pending to become active if the widget pointer 
+    // is non-zero, and the session pointer is zero (it will become active upon a call to
+    // currentModalSession). A QCocoaModalSessionInfo is considered pending to be stopped if
+    // the widget pointer is zero, and the session pointer is non-zero (it will be fully
+    // stopped in endModalSession().
+    QCocoaModalSessionInfo info = {widget, 0};
+    cocoaModalSessionStack.push(info);
+    updateChildrenWorksWhenModal();
+    currentModalSessionCached = 0;
+}
+
+void QEventDispatcherMacPrivate::endModalSession(QWidget *widget)
+{
+    // Mark all sessions attached to widget as pending to be stopped. We do this
+    // by setting the widget pointer to zero, but leave the session pointer.
+    // We don't tell cocoa to stop any sessions just yet, because cocoa only understands
+    // when we stop the _current_ modal session (which is the session on top of
+    // the stack, and might not belong to 'widget'). 
+    int stackSize = cocoaModalSessionStack.size();
+    for (int i=stackSize-1; i>=0; --i) {
+        QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
+        if (info.widget == widget)
+            info.widget = 0;
+    }
+
+    // Now we stop, and remove, all sessions marked as pending
+    // to be stopped on _top_ of the stack, if any:
+    bool needToInterruptEventDispatcher = false;
+    bool needToUpdateChildrenWorksWhenModal = false;
+
+    for (int i=stackSize-1; i>=0; --i) {
+        QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
+        if (info.widget)
+            break;
+        cocoaModalSessionStack.remove(i);
+        needToUpdateChildrenWorksWhenModal = true;
+        currentModalSessionCached = 0;
+        if (info.session) {
+            [NSApp endModalSession:info.session];
+            needToInterruptEventDispatcher = true;
+        }
+    }
+
+    if (needToUpdateChildrenWorksWhenModal)
+        updateChildrenWorksWhenModal();
+    if (needToInterruptEventDispatcher)
+        QEventDispatcherMac::instance()->interrupt();
+}
+
+#endif
+
+QEventDispatcherMacPrivate::QEventDispatcherMacPrivate()
+    : interrupt(false)
+{
+}
+
+QEventDispatcherMac::QEventDispatcherMac(QObject *parent)
+    : QAbstractEventDispatcher(*new QEventDispatcherMacPrivate, parent)
+{
+    Q_D(QEventDispatcherMac);
+    CFRunLoopSourceContext context;
+    bzero(&context, sizeof(CFRunLoopSourceContext));
+    context.info = d;
+    context.equal = QEventDispatcherMacPrivate::postedEventSourceEqualCallback;
+    context.perform = QEventDispatcherMacPrivate::postedEventsSourcePerformCallback;
+    d->postedEventsSource = CFRunLoopSourceCreate(0, 0, &context);
+    Q_ASSERT(d->postedEventsSource);
+    CFRunLoopAddSource(mainRunLoop(), d->postedEventsSource, kCFRunLoopCommonModes);
+
+    CFRunLoopObserverContext observerContext;
+    bzero(&observerContext, sizeof(CFRunLoopObserverContext));
+    observerContext.info = this;
+    d->waitingObserver = CFRunLoopObserverCreate(kCFAllocatorDefault,
+                                                 kCFRunLoopBeforeWaiting | kCFRunLoopAfterWaiting,
+                                                 true, 0,
+                                                 QEventDispatcherMacPrivate::waitingObserverCallback,
+                                                 &observerContext);
+    CFRunLoopAddObserver(mainRunLoop(), d->waitingObserver, kCFRunLoopCommonModes);
+
+    /* The first cycle in the loop adds the source and the events of the source
+       are not processed.
+       We use an observer to process the posted events for the first
+       execution of the loop. */
+    CFRunLoopObserverContext firstTimeObserverContext;
+    bzero(&firstTimeObserverContext, sizeof(CFRunLoopObserverContext));
+    firstTimeObserverContext.info = d;
+    d->firstTimeObserver = CFRunLoopObserverCreate(kCFAllocatorDefault,
+                                                   kCFRunLoopEntry,
+                                                   /* repeats = */ false,
+                                                   0,
+                                                   QEventDispatcherMacPrivate::firstLoopEntry,
+                                                   &firstTimeObserverContext);
+    CFRunLoopAddObserver(mainRunLoop(), d->firstTimeObserver, kCFRunLoopCommonModes);
+}
+
+void QEventDispatcherMacPrivate::waitingObserverCallback(CFRunLoopObserverRef,
+                                                          CFRunLoopActivity activity, void *info)
+{
+    if (activity == kCFRunLoopBeforeWaiting)
+        emit static_cast<QEventDispatcherMac*>(info)->aboutToBlock();
+    else
+        emit static_cast<QEventDispatcherMac*>(info)->awake();
+}
+
+Boolean QEventDispatcherMacPrivate::postedEventSourceEqualCallback(const void *info1, const void *info2)
+{
+    return info1 == info2;
+}
+
+inline static void processPostedEvents(QEventDispatcherMacPrivate *const d, const bool blockSendPostedEvents)
+{
+    if (blockSendPostedEvents || d->interrupt) {
+        CFRunLoopSourceSignal(d->postedEventsSource);
+    } else {
+        if (!d->threadData->canWait || (d->serialNumber != d->lastSerial)) {
+            d->lastSerial = d->serialNumber;
+            QApplicationPrivate::sendPostedEvents(0, 0, d->threadData);
+        }
+    }
+}
+
+void QEventDispatcherMacPrivate::firstLoopEntry(CFRunLoopObserverRef ref,
+                                                CFRunLoopActivity activity,
+                                                void *info)
+{
+    Q_UNUSED(ref);
+    Q_UNUSED(activity);
+    processPostedEvents(static_cast<QEventDispatcherMacPrivate *>(info), blockSendPostedEvents);
+}
+
+void QEventDispatcherMacPrivate::postedEventsSourcePerformCallback(void *info)
+{
+    processPostedEvents(static_cast<QEventDispatcherMacPrivate *>(info), blockSendPostedEvents);
+}
+
+void QEventDispatcherMac::interrupt()
+{
+    Q_D(QEventDispatcherMac);
+    d->interrupt = true;
+    wakeUp();
+
+#ifndef QT_MAC_USE_COCOA
+    CFRunLoopStop(mainRunLoop());
+#else
+    QMacCocoaAutoReleasePool pool;
+    // In case we wait for more events inside
+    // processEvents (or NSApp run), post a dummy to wake it up:
+    static const short NSAppShouldStopForQt = SHRT_MAX;
+    [NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined location:NSZeroPoint
+        modifierFlags:0 timestamp:0. windowNumber:0 context:0
+        subtype:NSAppShouldStopForQt data1:0 data2:0] atStart:NO];
+
+    if (d->activeModalSessionCount() == 0) {
+        // We should only stop NSApp if we actually started it (and
+        // not some 3rd party application, e.g. if we are a plugin).
+        if (d->nsAppRunCalledByQt)
+            [NSApp stop:NSApp];
+    }
+#endif
+}
+
+QEventDispatcherMac::~QEventDispatcherMac()
+{
+    Q_D(QEventDispatcherMac);
+    //timer cleanup
+    MacTimerHash::iterator it = QEventDispatcherMacPrivate::macTimerHash.begin();
+    while (it != QEventDispatcherMacPrivate::macTimerHash.end()) {
+        MacTimerInfo *t = it.value();
+        if (t->runLoopTimer) {
+            CFRunLoopTimerInvalidate(t->runLoopTimer);
+            CFRelease(t->runLoopTimer);
+        }
+        delete t;
+        ++it;
+    }
+    QEventDispatcherMacPrivate::macTimerHash.clear();
+
+    // Remove CFSockets from the runloop.
+    for (MacSocketHash::ConstIterator it = d->macSockets.constBegin(); it != d->macSockets.constEnd(); ++it) {
+        MacSocketInfo *socketInfo = (*it);
+        if (CFSocketIsValid(socketInfo->socket)) {
+            qt_mac_remove_socket_from_runloop(socketInfo->socket, socketInfo->runloop);
+            CFRunLoopSourceInvalidate(socketInfo->runloop);
+            CFRelease(socketInfo->runloop);
+            CFSocketInvalidate(socketInfo->socket);
+            CFRelease(socketInfo->socket);
+        }
+    }
+    CFRunLoopRemoveSource(mainRunLoop(), d->postedEventsSource, kCFRunLoopCommonModes);
+    CFRelease(d->postedEventsSource);
+
+    CFRunLoopObserverInvalidate(d->waitingObserver);
+    CFRelease(d->waitingObserver);
+
+    CFRunLoopObserverInvalidate(d->firstTimeObserver);
+    CFRelease(d->firstTimeObserver);
+}
+
+/////////////////////////////////////////////////////////////////////////////
+
+#ifdef QT_MAC_USE_COCOA
+
+QtMacInterruptDispatcherHelp* QtMacInterruptDispatcherHelp::instance = 0;
+
+QtMacInterruptDispatcherHelp::QtMacInterruptDispatcherHelp() : cancelled(false)
+{
+    // This is the whole point of encapsulation this code
+    // inside a class; we can make the code (inside destructor)
+    // execute on lower loop level:
+    deleteLater();
+}
+
+QtMacInterruptDispatcherHelp::~QtMacInterruptDispatcherHelp()
+{
+    if (cancelled)
+        return;
+
+    instance = 0;
+
+    if (QEventDispatcherMacPrivate::currentExecIsNSAppRun) {
+        int activeCount = QEventDispatcherMacPrivate::activeModalSessionCount();
+        if (activeCount > 0) {
+            // The problem we now have hit: [NSApp stop] will not stop NSApp
+            // if a session is active; it will stop the session instead.
+            // So to stop NSApp, we need to temporarily stop all the
+            // sessions, then stop NSApp, then restart the session on top again.
+            // We need to do this to ensure that we're not stuck inside
+            // [NSApp run] when we really should be running a modal session:
+            QEventDispatcherMacPrivate::temporarilyStopAllModalSessions();
+        }
+    }
+    // Always interrupt once more in case the modal session stack changed
+    // while processEvents was called manually from within the application:
+    QEventDispatcherMac::instance()->interrupt();
+}
+
+void QtMacInterruptDispatcherHelp::interruptLater() {
+    if (instance) {
+        instance->cancelled = true;
+        delete instance;
+    }
+    instance = new QtMacInterruptDispatcherHelp;
+}
+
+#endif
+
+QT_END_NAMESPACE