qt-creator/shared/qtlockedfile/qtlockedfile.h

/***************************************************************************
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** Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).
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** alternatively, in accordance with the terms contained in a written
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** GNU General Public License Usage
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** Public License versions 2.0 or 3.0 as published by the Free Software
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#ifndef QTLOCKEDFILE_H
#define QTLOCKEDFILE_H

#include <QtCore/QFile>

#if defined(Q_WS_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 SharedTools {

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

    QtLockedFile();
    QtLockedFile(const QString &name);
    ~QtLockedFile();
    
    bool lock(LockMode mode, bool block = true);
    bool unlock();
    bool isLocked() const;
    LockMode lockMode() const;
    
private:
#ifdef Q_OS_WIN
    Qt::HANDLE m_semaphore_hnd;
    Qt::HANDLE m_mutex_hnd;
#endif
    LockMode m_lock_mode;
};

} // namespace SharedTools

#endif // QTLOCKEDFILE_H