eventloop.h

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// SPDX-FileCopyrightText: Copyright (C) 2017 swift Project Community / Contributors
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-swift-pilot-client-1
 
 
#ifndef SWIFT_MISC_EVENTLOOP_H
#define SWIFT_MISC_EVENTLOOP_H
 
#include <QEventLoop>
#include <QObject>
#include <QPointer>
#include <QTimer>
 
namespace swift::misc
{
    class CEventLoop
    {
    public:
        CEventLoop() : m_guard(&m_eventLoop) {}
 
        CEventLoop(QObject *guard) : m_guard(guard)
        {
            Q_ASSERT(guard);
            QObject::connect(guard, &QObject::destroyed, &m_eventLoop, [this] { m_eventLoop.exit(TimedOut); });
        }
 
        template <typename T, typename F>
        void stopWhen(const T *sender, F signal)
        {
            QObject::connect(sender, signal, &m_eventLoop, [this] { m_eventLoop.exit(GotSignal); });
        }
 
        template <typename T, typename F1, typename F2>
        void stopWhen(const T *sender, F1 signal, F2 &&condition)
        {
            QObject::connect(sender, signal, &m_eventLoop,
                             [this, condition = std::forward<F2>(condition)](auto &&...args) {
                                 if (condition(std::forward<decltype(args)>(args)...)) { m_eventLoop.exit(GotSignal); }
                             });
        }
 
        bool exec(int timeoutMs)
        {
            if (timeoutMs >= 0)
            {
                QTimer::singleShot(timeoutMs, &m_eventLoop, [this] { m_eventLoop.exit(TimedOut); });
            }
            return m_eventLoop.exec() == GotSignal && isGuardAlive();
        }
 
        bool isGuardAlive() const { return m_guard; }
 
    private:
        enum Result
        {
            GotSignal = 0,
            TimedOut,
        };
        QEventLoop m_eventLoop;
        QPointer<QObject> m_guard;
    };
} // namespace swift::misc
 
#endif // SWIFT_MISC_EVENTLOOP_H