Support native event filter for Mac OS X

Ported from Qt 4 implementation, updated with
QAbstractEventDispatcher::filterNativeEvent() call.

Tested with an example.

Change-Id: I3271f8a565d06d80b7b48ba81728bcdb7b1c32e3
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>

7 files changed, 261 insertions, 14 deletions

diff --git a/src/plugins/platforms/cocoa/cocoa.pro b/src/plugins/platforms/cocoa/cocoa.pro
index 3ea5dc2d1c..ce46c46b0e 100644
--- a/src/plugins/platforms/cocoa/cocoa.pro
+++ b/src/plugins/platforms/cocoa/cocoa.pro
@@ -37,6 +37,7 @@ OBJECTIVE_SOURCES += main.mm \
     qcocoainputcontext.mm \
     qcocoaservices.mm \
     qcocoasystemtrayicon.mm \
+    qcocoaintrospection.mm \
 
 HEADERS += qcocoaintegration.h \
     qcocoatheme.h \
@@ -70,6 +71,7 @@ HEADERS += qcocoaintegration.h \
     qcocoainputcontext.h \
     qcocoaservices.h \
     qcocoasystemtrayicon.h \
+    qcocoaintrospection.h \
 
 RESOURCES += qcocoaresources.qrc
 
diff --git a/src/plugins/platforms/cocoa/qcocoaapplication.h b/src/plugins/platforms/cocoa/qcocoaapplication.h
index 783edada77..66700281ac 100644
--- a/src/plugins/platforms/cocoa/qcocoaapplication.h
+++ b/src/plugins/platforms/cocoa/qcocoaapplication.h
@@ -102,13 +102,14 @@
 - (BOOL)qt_filterEvent:(NSEvent *)event;
 @end
 
-@interface QNSApplication : NSApplication {
+@interface QT_MANGLE_NAMESPACE(QNSApplication) : NSApplication {
 }
 @end
 
 QT_BEGIN_NAMESPACE
 
 void qt_redirectNSApplicationSendEvent();
+void qt_resetNSApplicationSendEvent();
 
 QT_END_NAMESPACE
 
diff --git a/src/plugins/platforms/cocoa/qcocoaapplication.mm b/src/plugins/platforms/cocoa/qcocoaapplication.mm
index 5b646d8942..a50c480f1f 100644
--- a/src/plugins/platforms/cocoa/qcocoaapplication.mm
+++ b/src/plugins/platforms/cocoa/qcocoaapplication.mm
@@ -75,6 +75,7 @@
 
 #include <qcocoaapplication.h>
 
+#include <qcocoaintrospection.h>
 #include <qcocoaapplicationdelegate.h>
 #include <qcocoahelpers.h>
 #include <qguiapplication.h>
@@ -107,8 +108,6 @@ QT_USE_NAMESPACE
 
 - (void)qt_sendPostedMessage:(NSEvent *)event
 {
-    Q_UNUSED(event);
-/*
     // WARNING: data1 and data2 is truncated to from 64-bit to 32-bit on OS 10.5!
     // That is why we need to split the address in two parts:
     quint64 lower = [event data1];
@@ -131,14 +130,14 @@ QT_USE_NAMESPACE
     }
 
     delete args;
-*/
 }
 
+static const QByteArray q_macLocalEventType = QByteArrayLiteral("mac_generic_NSEvent");
+
 - (BOOL)qt_filterEvent:(NSEvent *)event
 {
-    Q_UNUSED(event);
-/*
-    if (qApp && qApp->macEventFilter(0, reinterpret_cast<EventRef>(event)))
+    if (qApp && qApp->eventDispatcher()->
+            filterNativeEvent(q_macLocalEventType, static_cast<void*>(event), 0))
         return true;
 
     if ([event type] == NSApplicationDefined) {
@@ -150,13 +149,13 @@ QT_USE_NAMESPACE
                 break;
         }
     }
-*/
+
     return false;
 }
 
 @end
 
-@implementation QNSApplication
+@implementation QT_MANGLE_NAMESPACE(QNSApplication)
 
 - (void)qt_sendEvent_original:(NSEvent *)event
 {
@@ -190,8 +189,7 @@ QT_BEGIN_NAMESPACE
 
 void qt_redirectNSApplicationSendEvent()
 {
-/*
-    if ([NSApp isMemberOfClass:[QNSApplication class]]) {
+    if ([NSApp isMemberOfClass:[QT_MANGLE_NAMESPACE(QNSApplication) class]]) {
         // No need to change implementation since Qt
         // already controls a subclass of NSApplication
         return;
@@ -204,10 +202,16 @@ void qt_redirectNSApplicationSendEvent()
     qt_cocoa_change_implementation(
             [NSApplication class],
             @selector(sendEvent:),
-            [QNSApplication class],
+            [QT_MANGLE_NAMESPACE(QNSApplication) class],
             @selector(qt_sendEvent_replacement:),
             @selector(qt_sendEvent_original:));
- */
  }
 
+void qt_resetNSApplicationSendEvent()
+{
+    qt_cocoa_change_back_implementation([NSApplication class],
+                                         @selector(sendEvent:),
+                                         @selector(QT_MANGLE_NAMESPACE(qt_sendEvent_original):));
+}
+
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/cocoa/qcocoahelpers.h b/src/plugins/platforms/cocoa/qcocoahelpers.h
index 45c35cccbf..2de955c273 100644
--- a/src/plugins/platforms/cocoa/qcocoahelpers.h
+++ b/src/plugins/platforms/cocoa/qcocoahelpers.h
@@ -129,6 +129,34 @@ bool qt_mac_execute_apple_script(const QString &script, AEDesc *ret);
 // accelerators.
 QString qt_mac_removeAmpersandEscapes(QString s);
 
+enum {
+    QtCocoaEventSubTypeWakeup       = SHRT_MAX,
+    QtCocoaEventSubTypePostMessage  = SHRT_MAX-1
+};
+
+class QCocoaPostMessageArgs {
+public:
+    id target;
+    SEL selector;
+    int argCount;
+    id arg1;
+    id arg2;
+    QCocoaPostMessageArgs(id target, SEL selector, int argCount=0, id arg1=0, id arg2=0)
+        : target(target), selector(selector), argCount(argCount), arg1(arg1), arg2(arg2)
+    {
+        [target retain];
+        [arg1 retain];
+        [arg2 retain];
+    }
+
+    ~QCocoaPostMessageArgs()
+    {
+        [arg2 release];
+        [arg1 release];
+        [target release];
+    }
+};
+
 QT_END_NAMESPACE
 
 #endif //QCOCOAHELPERS_H
diff --git a/src/plugins/platforms/cocoa/qcocoaintegration.mm b/src/plugins/platforms/cocoa/qcocoaintegration.mm
index f17e97c115..a361027b49 100644
--- a/src/plugins/platforms/cocoa/qcocoaintegration.mm
+++ b/src/plugins/platforms/cocoa/qcocoaintegration.mm
@@ -192,7 +192,8 @@ QCocoaIntegration::QCocoaIntegration()
 
     qApp->setAttribute(Qt::AA_DontUseNativeMenuBar, false);
 
-    NSApplication *cocoaApplication = [NSApplication sharedApplication];
+    NSApplication *cocoaApplication = [QT_MANGLE_NAMESPACE(QNSApplication) sharedApplication];
+    qt_redirectNSApplicationSendEvent();
 
     if (qEnvironmentVariableIsEmpty("QT_MAC_DISABLE_FOREGROUND_APPLICATION_TRANSFORM")) {
         // Applications launched from plain executables (without an app
@@ -233,6 +234,8 @@ QCocoaIntegration::QCocoaIntegration()
 
 QCocoaIntegration::~QCocoaIntegration()
 {
+    qt_resetNSApplicationSendEvent();
+
     QCocoaAutoReleasePool pool;
     if (!QCoreApplication::testAttribute(Qt::AA_MacPluginApplication)) {
         // remove the apple event handlers installed by QCocoaApplicationDelegate
diff --git a/src/plugins/platforms/cocoa/qcocoaintrospection.h b/src/plugins/platforms/cocoa/qcocoaintrospection.h
new file mode 100644
index 0000000000..ffe3d96290
--- /dev/null
+++ b/src/plugins/platforms/cocoa/qcocoaintrospection.h
@@ -0,0 +1,84 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 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, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/****************************************************************************
+**
+** 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 <qglobal.h>
+#import <objc/objc-class.h>
+
+QT_BEGIN_NAMESPACE
+
+void qt_cocoa_change_implementation(Class baseClass, SEL originalSel, Class proxyClass, SEL replacementSel = 0, SEL backupSel = 0);
+void qt_cocoa_change_back_implementation(Class baseClass, SEL originalSel, SEL backupSel);
+
+QT_END_NAMESPACE
diff --git a/src/plugins/platforms/cocoa/qcocoaintrospection.mm b/src/plugins/platforms/cocoa/qcocoaintrospection.mm
new file mode 100644
index 0000000000..e1af986487
--- /dev/null
+++ b/src/plugins/platforms/cocoa/qcocoaintrospection.mm
@@ -0,0 +1,125 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 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, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/****************************************************************************
+**
+** 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 "qcocoaintrospection.h"
+
+QT_BEGIN_NAMESPACE
+
+void qt_cocoa_change_implementation(Class baseClass, SEL originalSel, Class proxyClass, SEL replacementSel, SEL backupSel)
+{
+#ifndef QT_MAC_USE_COCOA
+    if (QSysInfo::MacintoshVersion >= QSysInfo::MV_10_5)
+#endif
+    {
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
+        // The following code replaces the _implementation_ for the selector we want to hack
+        // (originalSel) with the implementation found in proxyClass. Then it creates
+        // a new 'backup' method inside baseClass containing the old, original,
+        // implementation (fakeSel). You can let the proxy implementation of originalSel
+        // call fakeSel if needed (similar approach to calling a super class implementation).
+        // fakeSel must also be implemented in proxyClass, as the signature is used
+        // as template for the method one we add into baseClass.
+        // NB: You will typically never create any instances of proxyClass; we use it
+        // only for stealing its contents and put it into baseClass.
+        if (!replacementSel)
+            replacementSel = originalSel;
+
+        Method originalMethod = class_getInstanceMethod(baseClass, originalSel);
+        Method replacementMethod = class_getInstanceMethod(proxyClass, replacementSel);
+        IMP originalImp = method_setImplementation(originalMethod, method_getImplementation(replacementMethod));
+
+        if (backupSel) {
+            Method backupMethod = class_getInstanceMethod(proxyClass, backupSel);
+            class_addMethod(baseClass, backupSel, originalImp, method_getTypeEncoding(backupMethod));
+        }
+#endif
+    }
+}
+
+void qt_cocoa_change_back_implementation(Class baseClass, SEL originalSel, SEL backupSel)
+{
+#ifndef QT_MAC_USE_COCOA
+    if (QSysInfo::MacintoshVersion >= QSysInfo::MV_10_5)
+#endif
+    {
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
+        Method originalMethod = class_getInstanceMethod(baseClass, originalSel);
+        Method backupMethodInBaseClass = class_getInstanceMethod(baseClass, backupSel);
+        method_setImplementation(originalMethod, method_getImplementation(backupMethodInBaseClass));
+#endif
+    }
+}
+
+QT_END_NAMESPACE