braveheart.cpp

/*
    SPDX-FileCopyrightText: 2016 Daniel Vrátil <dvratil@kde.org>
 
    SPDX-License-Identifier: LGPL-2.0-or-later
*/
 
#include <config-akonadi.h>
 
#if HAVE_MALLOC_TRIM
 
#include <QCoreApplication>
#include <QThread>
#include <QTimer>
#include <QVariant>
 
#include <chrono>
#include <malloc.h>
 
using namespace std::chrono_literals;
 
namespace Akonadi
{
class Braveheart
{
private:
    static void sonOfScotland()
    {
        Q_ASSERT(qApp->thread() == QThread::currentThread());
 
        if (!qApp->property("__Akonadi__Braveheart").isNull()) {
            // One Scottish warrior is enough....
            return;
        }
        auto freedom = new QTimer(qApp);
        QObject::connect(freedom, &QTimer::timeout, freedom, []() {
            // They may take our lives, but they will never
            // take our memory!
            malloc_trim(50 * 1024 * 1024);
        });
        // Fight for freedom every 15 minutes
        freedom->start(15min);
        qApp->setProperty("__Akonadi__Braveheart", true);
    }
 
public:
    explicit Braveheart()
    {
        qAddPreRoutine([]() {
            if (qApp->thread() != QThread::currentThread()) {
                QTimer::singleShot(0, qApp, sonOfScotland);
            } else {
                sonOfScotland();
            }
        });
    }
};
 
namespace
{
Braveheart Wallace; // clazy:exclude=non-pod-global-static
 
}
 
} // namespace Akonadi
 
#endif // HAVE_MALLOC_TRIM