223 lines
6.7 KiB
C++
223 lines
6.7 KiB
C++
/****************************************************************************
|
|
**
|
|
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
|
|
** Contact: http://www.qt-project.org/
|
|
**
|
|
** This file is part of the QtCore module of the Qt Toolkit.
|
|
**
|
|
** $QT_BEGIN_LICENSE:LGPL$
|
|
** GNU Lesser General Public License Usage
|
|
** 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.
|
|
**
|
|
** 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.
|
|
**
|
|
** Other Usage
|
|
** Alternatively, this file may be used in accordance with the terms and
|
|
** conditions contained in a signed written agreement between you and Nokia.
|
|
**
|
|
**
|
|
**
|
|
**
|
|
**
|
|
**
|
|
** $QT_END_LICENSE$
|
|
**
|
|
****************************************************************************/
|
|
|
|
#include "qwineventnotifier.h"
|
|
|
|
#include "qeventdispatcher_win_p.h"
|
|
#include "qcoreapplication.h"
|
|
|
|
#include <private/qthread_p.h>
|
|
|
|
QT_BEGIN_NAMESPACE
|
|
|
|
/*!
|
|
\class QWinEventNotifier
|
|
\brief The QWinEventNotifier class provides support for the Windows Wait functions.
|
|
|
|
The QWinEventNotifier class makes it possible to use the wait
|
|
functions on windows in a asynchronous manner. With this class,
|
|
you can register a HANDLE to an event and get notification when
|
|
that event becomes signalled. The state of the event is not modified
|
|
in the process so if it is a manual reset event you will need to
|
|
reset it after the notification.
|
|
|
|
Once you have created a event object using Windows API such as
|
|
CreateEvent() or OpenEvent(), you can create an event notifier to
|
|
monitor the event handle. If the event notifier is enabled, it will
|
|
emit the activated() signal whenever the corresponding event object
|
|
is signalled.
|
|
|
|
The setEnabled() function allows you to disable as well as enable the
|
|
event notifier. It is generally advisable to explicitly enable or
|
|
disable the event notifier. A disabled notifier does nothing when the
|
|
event object is signalled (the same effect as not creating the
|
|
event notifier). Use the isEnabled() function to determine the
|
|
notifier's current status.
|
|
|
|
Finally, you can use the setHandle() function to register a new event
|
|
object, and the handle() function to retrieve the event handle.
|
|
|
|
\b{Further information:}
|
|
Although the class is called QWinEventNotifier, it can be used for
|
|
certain other objects which are so-called synchronization
|
|
objects, such as Processes, Threads, Waitable timers.
|
|
|
|
\warning This class is only available on Windows.
|
|
*/
|
|
|
|
/*!
|
|
\fn void QWinEventNotifier::activated(HANDLE hEvent)
|
|
|
|
This signal is emitted whenever the event notifier is enabled and
|
|
the corresponding HANDLE is signalled.
|
|
|
|
The state of the event is not modified in the process, so if it is a
|
|
manual reset event, you will need to reset it after the notification.
|
|
|
|
The object is passed in the \a hEvent parameter.
|
|
|
|
\sa handle()
|
|
*/
|
|
|
|
/*!
|
|
Constructs an event notifier with the given \a parent.
|
|
*/
|
|
|
|
QWinEventNotifier::QWinEventNotifier(QObject *parent)
|
|
: QObject(parent), handleToEvent(0), enabled(false)
|
|
{}
|
|
|
|
/*!
|
|
Constructs an event notifier with the given \a parent. It enables
|
|
the \a notifier, and watches for the event \a hEvent.
|
|
|
|
The notifier is enabled by default, i.e. it emits the activated() signal
|
|
whenever the corresponding event is signalled. However, it is generally
|
|
advisable to explicitly enable or disable the event notifier.
|
|
|
|
\sa setEnabled(), isEnabled()
|
|
*/
|
|
|
|
QWinEventNotifier::QWinEventNotifier(HANDLE hEvent, QObject *parent)
|
|
: QObject(parent), handleToEvent(hEvent), enabled(false)
|
|
{
|
|
Q_D(QObject);
|
|
QEventDispatcherWin32 *eventDispatcher = qobject_cast<QEventDispatcherWin32 *>(d->threadData->eventDispatcher);
|
|
Q_ASSERT_X(eventDispatcher, "QWinEventNotifier::QWinEventNotifier()",
|
|
"Cannot create a win event notifier without a QEventDispatcherWin32");
|
|
eventDispatcher->registerEventNotifier(this);
|
|
enabled = true;
|
|
}
|
|
|
|
/*!
|
|
Destroys this notifier.
|
|
*/
|
|
|
|
QWinEventNotifier::~QWinEventNotifier()
|
|
{
|
|
setEnabled(false);
|
|
}
|
|
|
|
/*!
|
|
Register the HANDLE \a hEvent. The old HANDLE will be automatically
|
|
unregistered.
|
|
|
|
\b Note: The notifier will be disabled as a side effect and needs
|
|
to be re-enabled.
|
|
|
|
\sa handle(), setEnabled()
|
|
*/
|
|
|
|
void QWinEventNotifier::setHandle(HANDLE hEvent)
|
|
{
|
|
setEnabled(false);
|
|
handleToEvent = hEvent;
|
|
}
|
|
|
|
/*!
|
|
Returns the HANDLE that has been registered in the notifier.
|
|
|
|
\sa setHandle()
|
|
*/
|
|
|
|
HANDLE QWinEventNotifier::handle() const
|
|
{
|
|
return handleToEvent;
|
|
}
|
|
|
|
/*!
|
|
Returns true if the notifier is enabled; otherwise returns false.
|
|
|
|
\sa setEnabled()
|
|
*/
|
|
|
|
bool QWinEventNotifier::isEnabled() const
|
|
{
|
|
return enabled;
|
|
}
|
|
|
|
/*!
|
|
If \a enable is true, the notifier is enabled; otherwise the notifier
|
|
is disabled.
|
|
|
|
\sa isEnabled(), activated()
|
|
*/
|
|
|
|
void QWinEventNotifier::setEnabled(bool enable)
|
|
{
|
|
if (enabled == enable) // no change
|
|
return;
|
|
enabled = enable;
|
|
|
|
Q_D(QObject);
|
|
QEventDispatcherWin32 *eventDispatcher = qobject_cast<QEventDispatcherWin32 *>(d->threadData->eventDispatcher);
|
|
if (!eventDispatcher) // perhaps application is shutting down
|
|
return;
|
|
|
|
if (enabled)
|
|
eventDispatcher->registerEventNotifier(this);
|
|
else
|
|
eventDispatcher->unregisterEventNotifier(this);
|
|
}
|
|
|
|
/*!
|
|
\reimp
|
|
*/
|
|
|
|
bool QWinEventNotifier::event(QEvent * e)
|
|
{
|
|
if (e->type() == QEvent::ThreadChange) {
|
|
if (enabled) {
|
|
QMetaObject::invokeMethod(this, "setEnabled", Qt::QueuedConnection,
|
|
Q_ARG(bool, enabled));
|
|
setEnabled(false);
|
|
}
|
|
}
|
|
QObject::event(e); // will activate filters
|
|
if (e->type() == QEvent::WinEventAct) {
|
|
emit activated(handleToEvent);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
QT_END_NAMESPACE
|