profilelocker.cpp

Go to the documentation of this file.

/*
    Copyright © 2015-2019 by The qTox Project Contributors
 
    This file is part of qTox, a Qt-based graphical interface for Tox.
 
    qTox is libre software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
 
    qTox is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with qTox.  If not, see <http://www.gnu.org/licenses/>.
*/
 
 
#include "profilelocker.h"
#include "src/persistence/settings.h"
#include <QDebug>
#include <QDir>
 
using namespace std;
 
unique_ptr<QLockFile> ProfileLocker::lockfile;
QString ProfileLocker::curLockName;
 
QString ProfileLocker::lockPathFromName(const QString& name)
{
    return Settings::getInstance().getPaths().getSettingsDirPath() + '/' + name + ".lock";
}
 
bool ProfileLocker::isLockable(QString profile)
{
    // If we already have the lock, it's definitely lockable
    if (lockfile && curLockName == profile)
        return true;
 
    QLockFile newLock(lockPathFromName(profile));
    return newLock.tryLock();
}
 
bool ProfileLocker::lock(QString profile)
{
    if (lockfile && curLockName == profile)
        return true;
 
    QLockFile* newLock = new QLockFile(lockPathFromName(profile));
    newLock->setStaleLockTime(0);
    if (!newLock->tryLock()) {
        delete newLock;
        return false;
    }
 
    unlock();
    lockfile.reset(newLock);
    curLockName = profile;
    return true;
}
 
void ProfileLocker::unlock()
{
    if (!lockfile)
        return;
 
    lockfile->unlock();
    lockfile.reset();
    curLockName.clear();
}
 
void ProfileLocker::assertLock()
{
    if (!lockfile) {
        qCritical() << "assertLock: We don't seem to own any lock!";
        deathByBrokenLock();
    }
 
    if (!QFile(lockPathFromName(curLockName)).exists()) {
        QString tmp = curLockName;
        unlock();
        if (lock(tmp)) {
            qCritical() << "assertLock: Lock file was lost, but could be restored";
        } else {
            qCritical() << "assertLock: Lock file was lost, and could *NOT* be restored";
            deathByBrokenLock();
        }
    }
}
 
void ProfileLocker::deathByBrokenLock()
{
    qCritical() << "Lock is *BROKEN*, exiting immediately";
    abort();
}
 
bool ProfileLocker::hasLock()
{
    return lockfile.operator bool();
}
 
QString ProfileLocker::getCurLockName()
{
    if (lockfile)
        return curLockName;
    else
        return QString();
}