referencedevice.hpp

/* Copyright (c) 2014, The Nuria Project
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *    1. The origin of this software must not be misrepresented; you must not
 *       claim that you wrote the original software. If you use this software
 *       in a product, an acknowledgment in the product documentation would be
 *       appreciated but is not required.
 *    2. Altered source versions must be plainly marked as such, and must not be
 *       misrepresented as being the original software.
 *    3. This notice may not be removed or altered from any source
 *       distribution.
 */

#ifndef NURIA_REFERENCEDEVICE_HPP
#define NURIA_REFERENCEDEVICE_HPP

#include <QIODevice>
#include "essentials.hpp"

namespace Nuria {

class ReferenceDevicePrivate;

class NURIA_CORE_EXPORT ReferenceDevice : public QIODevice {
    Q_OBJECT
public:
    
    explicit ReferenceDevice (QIODevice *referencedDevice, QObject *parent = 0);
    
    ~ReferenceDevice () override;
    
    QIODevice *referencedDevice () const;
    
    qint64 rangeBegin () const;
    
    qint64 rangeEnd () const;
    
    void setRange (qint64 begin, qint64 end = -1);
    
    void extendRange (qint64 bytes);
    
    // 
    bool isSequential () const override;
    bool open (OpenMode mode) override;
    void close () override;
    qint64 pos () const override;
    qint64 size () const override;
    bool seek (qint64 pos) override;
    bool atEnd () const override;
    bool reset () override;
    qint64 bytesAvailable () const override;
    
protected:
    qint64 readData(char *data, qint64 maxlen);
    qint64 writeData(const char *data, qint64 len);
    
private:
    void referencedDeviceDestroyed ();
    void autoExtendRange ();
    
    ReferenceDevicePrivate *d_ptr;
    
};

}

#endif // NURIA_REFERENCEDEVICE_HPP