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// 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