/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, 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, Digia gives you certain additional
** rights.  These rights are described in the Digia 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.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QFILEDEVICE_P_H
#define QFILEDEVICE_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "private/qiodevice_p.h"
#include "private/qringbuffer_p.h"

QT_BEGIN_NAMESPACE

class QAbstractFileEngine;
class QFSFileEngine;

class QFileDevicePrivate : public QIODevicePrivate
{
    Q_DECLARE_PUBLIC(QFileDevice)
protected:
    QFileDevicePrivate();
    ~QFileDevicePrivate();

    virtual QAbstractFileEngine *engine() const;

    QFileDevice::FileHandleFlags handleFlags;

    mutable QAbstractFileEngine *fileEngine;
    bool lastWasWrite;
    QRingBuffer writeBuffer;
    inline bool ensureFlushed() const;

    bool putCharHelper(char c);

    QFileDevice::FileError error;
    void setError(QFileDevice::FileError err);
    void setError(QFileDevice::FileError err, const QString &errorString);
    void setError(QFileDevice::FileError err, int errNum);

    mutable qint64 cachedSize;
};

inline bool QFileDevicePrivate::ensureFlushed() const
{
    // This function ensures that the write buffer has been flushed (const
    // because certain const functions need to call it.
    if (lastWasWrite) {
        const_cast<QFileDevicePrivate *>(this)->lastWasWrite = false;
        if (!const_cast<QFileDevice *>(q_func())->flush())
            return false;
    }
    return true;
}

QT_END_NAMESPACE

#endif // QFILEDEVICE_P_H
