goldendict-ng/thirdparty/qtsingleapplication/src/qtlockedfile.h

/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the Qt Solutions component.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
**     of its contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QTLOCKEDFILE_H
#define QTLOCKEDFILE_H

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

#if defined(Q_OS_WIN)
#  if !defined(QT_QTLOCKEDFILE_EXPORT) && !defined(QT_QTLOCKEDFILE_IMPORT)
#    define QT_QTLOCKEDFILE_EXPORT
#  elif defined(QT_QTLOCKEDFILE_IMPORT)
#    if defined(QT_QTLOCKEDFILE_EXPORT)
#      undef QT_QTLOCKEDFILE_EXPORT
#    endif
#    define QT_QTLOCKEDFILE_EXPORT __declspec(dllimport)
#  elif defined(QT_QTLOCKEDFILE_EXPORT)
#    undef QT_QTLOCKEDFILE_EXPORT
#    define QT_QTLOCKEDFILE_EXPORT __declspec(dllexport)
#  endif
#else
#  define QT_QTLOCKEDFILE_EXPORT
#endif

namespace QtLP_Private {

class QT_QTLOCKEDFILE_EXPORT QtLockedFile : public QFile
{
public:
    enum LockMode { NoLock = 0, ReadLock, WriteLock };

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

    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