qtconcurrentrunbase.h

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#ifndef QTCONCURRENT_RUNBASE_H
#define QTCONCURRENT_RUNBASE_H

#include <QtCore/qglobal.h>

#ifndef QT_NO_CONCURRENT

#include <QtCore/qfuture.h>
#include <QtCore/qrunnable.h>
#include <QtCore/qthreadpool.h>

QT_BEGIN_HEADER
QT_BEGIN_NAMESPACE

QT_MODULE(Core)

#ifndef 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; };
};

template <typename T>
class RunFunctionTaskBase : public QFutureInterface<T> , public QRunnable
{
public:
    QFuture<T> start()
    {
        this->setRunnable(this);
        this->reportStarted();
        QFuture<T> future = this->future();
        QThreadPool::globalInstance()->start(this, /*m_priority*/ 0);
        return future;
    }

    void run() {}
    virtual void runFunctor() = 0;
};

template <typename T>
class RunFunctionTask : public RunFunctionTaskBase<T>
{
public:
    void run()
    {
        if (this->isCanceled()) {
            this->reportFinished();
            return;
        }
#ifndef QT_NO_EXCEPTIONS
        try {
#endif
            this->runFunctor();
#ifndef QT_NO_EXCEPTIONS
        } catch (QtConcurrent::Exception &e) {
            QFutureInterface<T>::reportException(e);
        } catch (...) {
            QFutureInterface<T>::reportException(QtConcurrent::UnhandledException());
        }
#endif

        this->reportResult(result);
        this->reportFinished();
    }
    T result;
};

template <>
class RunFunctionTask<void> : public RunFunctionTaskBase<void>
{
public:
    void run()
    {
        if (this->isCanceled()) {
            this->reportFinished();
            return;
        }
#ifndef QT_NO_EXCEPTIONS
        try {
#endif
            this->runFunctor();
#ifndef QT_NO_EXCEPTIONS
        } catch (QtConcurrent::Exception &e) {
            QFutureInterface<void>::reportException(e);
        } catch (...) {
            QFutureInterface<void>::reportException(QtConcurrent::UnhandledException());
        }
#endif
        this->reportFinished();
    }
};

} //namespace QtConcurrent

#endif //qdoc

QT_END_NAMESPACE
QT_END_HEADER

#endif // QT_NO_CONCURRENT

#endif