qt6-bb10/src/concurrent/qtconcurrentrunbase.h

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4.3 KiB
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/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtConcurrent 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.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef QTCONCURRENT_RUNBASE_H
#define QTCONCURRENT_RUNBASE_H
#include <QtConcurrent/qtconcurrent_global.h>
#ifndef QT_NO_CONCURRENT
#include <QtCore/qfuture.h>
#include <QtCore/qrunnable.h>
#include <QtCore/qthreadpool.h>
#include <type_traits>
#include <utility>
QT_BEGIN_NAMESPACE
#ifndef Q_QDOC
namespace QtConcurrent {
template <typename T>
struct SelectSpecialization
{
template <class Normal, class Void>
struct Type { typedef Normal type; };
};
template <>
struct SelectSpecialization<void>
{
template <class Normal, class Void>
struct Type { typedef Void type; };
};
struct TaskStartParameters
{
QThreadPool *threadPool = QThreadPool::globalInstance();
int priority = 0;
};
template <typename T>
class RunFunctionTaskBase : public QRunnable
{
public:
QFuture<T> start()
{
return start(TaskStartParameters());
}
QFuture<T> start(const TaskStartParameters &parameters)
{
promise.setThreadPool(parameters.threadPool);
promise.setRunnable(this);
promise.reportStarted();
QFuture<T> theFuture = promise.future();
parameters.threadPool->start(this, parameters.priority);
return theFuture;
}
// For backward compatibility
QFuture<T> start(QThreadPool *pool) { return start({pool, 0}); }
void run() override
{
if (promise.isCanceled()) {
promise.reportFinished();
return;
}
#ifndef QT_NO_EXCEPTIONS
try {
#endif
runFunctor();
#ifndef QT_NO_EXCEPTIONS
} catch (QException &e) {
promise.reportException(e);
} catch (...) {
promise.reportException(QUnhandledException());
}
#endif
reportResult();
promise.reportFinished();
}
protected:
virtual void runFunctor() = 0;
virtual void reportResult() {}
QFutureInterface<T> promise;
};
template <typename T>
class RunFunctionTask : public RunFunctionTaskBase<T>
{
protected:
void reportResult() override
{
if constexpr (std::is_move_constructible_v<T>)
this->promise.reportAndMoveResult(std::move(result));
else if constexpr (std::is_copy_constructible_v<T>)
this->promise.reportResult(result);
}
T result;
};
template <>
class RunFunctionTask<void> : public RunFunctionTaskBase<void> {};
} //namespace QtConcurrent
#endif //Q_QDOC
QT_END_NAMESPACE
#endif // QT_NO_CONCURRENT
#endif