Revision control
++ // Copyright (C) 2018 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
++ // Qt-Security score:significant reason:default
++
++ #ifndef QTESTSUPPORT_CORE_H
++ #define QTESTSUPPORT_CORE_H
++
++ #include <QtCore/qcoreapplication.h>
++ #include <QtCore/qdeadlinetimer.h>
++
++ #include <chrono>
++
++ QT_BEGIN_NAMESPACE
++
++ namespace QTest {
++
++ Q_CORE_EXPORT void qSleep(int ms);
++ Q_CORE_EXPORT void qSleep(std::chrono::milliseconds msecs);
++
++ extern Q_CORE_EXPORT std::atomic<std::chrono::milliseconds> defaultTryTimeout;
++
++ namespace Internal {
++ enum class WaitForResult {
++ Failed = -1,
++ NotYet = 0,
++ Done = 1,
++ };
++
++ inline bool waitForMore(bool) { return true; }
++ inline bool waitForMore(WaitForResult value) { return value == WaitForResult::NotYet; }
++
++ inline bool waitForSucceeded(bool value) { return value; }
++ inline bool waitForSucceeded(WaitForResult value) { return value >= WaitForResult::Done; }
++ }
++
++ template <typename Functor>
++ [[nodiscard]] bool
++ qWaitFor(Functor predicate, QDeadlineTimer deadline = QDeadlineTimer(
++ defaultTryTimeout.load(std::memory_order_relaxed)))
++ {
++ using Internal::waitForMore; // customization point
++ using Internal::waitForSucceeded; // customization point
++
++ // We should not spin the event loop in case the predicate is already true,
++ // otherwise we might send new events that invalidate the predicate.
++ if (waitForSucceeded(predicate()))
++ return true;
++
++ // qWait() is expected to spin the event loop at least once, even when
++ // called with a small timeout like 1ns.
++
++ do {
++ // We explicitly do not pass the remaining time to processEvents, as
++ // that would keep spinning processEvents for the whole duration if
++ // new events were posted as part of processing events, and we need
++ // to return back to this function to check the predicate between
++ // each pass of processEvents. Our own timer will take care of the
++ // timeout.
++ QCoreApplication::processEvents(QEventLoop::AllEvents);
++ QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
++
++ if (auto predresult = predicate(); waitForSucceeded(predresult))
++ return true;
++ else if (!waitForMore(predresult))
++ return false;
++
++ using namespace std::chrono;
++
++ if (const auto remaining = deadline.remainingTimeAsDuration(); remaining > 0ns)
++ qSleep((std::min)(10ms, ceil<milliseconds>(remaining)));
++
++ } while (!deadline.hasExpired());
++
++ return waitForSucceeded(predicate()); // Last chance
++ }
++
++ template <typename Functor>
++ [[nodiscard]] bool qWaitFor(Functor predicate, int timeout)
++ {
++ return qWaitFor(predicate, QDeadlineTimer{timeout, Qt::PreciseTimer});
++ }
++
++ Q_CORE_EXPORT void qWait(int ms);
++
++ Q_CORE_EXPORT void qWait(std::chrono::milliseconds msecs);
++
++ } // namespace QTest
++
++ QT_END_NAMESPACE
++
++ #endif