/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
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** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
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** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QSYSTEMSEMAPHORE_H
#define QSYSTEMSEMAPHORE_H

#include <QtCore/qstring.h>
#include <QtCore/qscopedpointer.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Core)

#ifndef QT_NO_SYSTEMSEMAPHORE

class QSystemSemaphorePrivate;

class Q_CORE_EXPORT QSystemSemaphore
{

public:
    enum AccessMode
    {
        Open,
        Create
    };

    enum SystemSemaphoreError
    {
        NoError,
        PermissionDenied,
        KeyError,
        AlreadyExists,
        NotFound,
        OutOfResources,
        UnknownError
    };

    QSystemSemaphore(const QString &key, int initialValue = 0, AccessMode mode = Open);
    ~QSystemSemaphore();

    void setKey(const QString &key, int initialValue = 0, AccessMode mode = Open);
    QString key() const;

    bool acquire();
    bool release(int n = 1);

    SystemSemaphoreError error() const;
    QString errorString() const;

private:
    Q_DISABLE_COPY(QSystemSemaphore)
    QScopedPointer<QSystemSemaphorePrivate> d;
};

#endif // QT_NO_SYSTEMSEMAPHORE

QT_END_NAMESPACE

QT_END_HEADER

#endif // QSYSTEMSEMAPHORE_H