/**
 * Copyright (c) 2011-2018 by Andrew Mustun. All rights reserved.
 * 
 * This file is part of the QCAD project.
 *
 * QCAD is free 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.
 *
 * QCAD 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 QCAD.
 */

#ifndef RLOCKEDFILE_H
#define RLOCKEDFILE_H

#include "core_global.h"

#include <QtCore/QFile>
#ifdef Q_OS_WIN
#include <QtCore/QVector>
#endif

class QCADCORE_EXPORT RLockedFile : public QFile
{
public:
    enum LockMode { NoLock = 0, ReadLock, WriteLock };

    RLockedFile();
    RLockedFile(const QString &name);
    ~RLockedFile();

    bool open(OpenMode mode);

    bool lock(LockMode mode, bool block = true);
    bool unlock();
    bool isLocked() const;
    LockMode lockMode() const;

private:
#ifdef Q_OS_WIN
    Qt::HANDLE wmutex;
    Qt::HANDLE rmutex;
    QVector<Qt::HANDLE> rmutexes;
    QString mutexname;

    Qt::HANDLE getMutexHandle(int idx, bool doCreate);
    bool waitMutex(Qt::HANDLE mutex, bool doBlock);

#endif
    LockMode m_lock_mode;
};

#endif
