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#ifndef QNONCONTIGUOUSBYTEDEVICE_H

#define QNONCONTIGUOUSBYTEDEVICE_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists for the convenience

// of a number of Qt sources files.  This header file may change from

// version to version without notice, or even be removed.

//

// We mean it.

//

#include <QtCore/qobject.h>

#include <QtCore/qbytearray.h>

#include <QtCore/qbuffer.h>

#include <QtCore/qiodevice.h>

#include "private/qringbuffer_p.h"

QT_BEGIN_NAMESPACE

class Q_CORE_EXPORT QNonContiguousByteDevice : public QObject

{

    Q_OBJECT

public:

    virtual const char* readPointer(qint64 maximumLength, qint64 &len) = 0;

    virtual bool advanceReadPointer(qint64 amount) = 0;

    virtual bool atEnd() = 0;

    virtual bool reset() = 0;

    void disableReset();

    virtual qint64 size() = 0;

    virtual ~QNonContiguousByteDevice();

protected:

    QNonContiguousByteDevice();

    bool resetDisabled;

Q_SIGNALS:

    void readyRead();

    void readProgress(qint64 current, qint64 total);

};

class Q_CORE_EXPORT QNonContiguousByteDeviceFactory

{

public:

    static QNonContiguousByteDevice* create(QIODevice *device);

    static QNonContiguousByteDevice* create(QByteArray *byteArray);

    static QNonContiguousByteDevice* create(QRingBuffer *ringBuffer);

    static QIODevice* wrap(QNonContiguousByteDevice* byteDevice);

};

// the actual implementations

//

class QNonContiguousByteDeviceByteArrayImpl : public QNonContiguousByteDevice

{

public:

    QNonContiguousByteDeviceByteArrayImpl(QByteArray *ba);

    ~QNonContiguousByteDeviceByteArrayImpl();

    const char* readPointer(qint64 maximumLength, qint64 &len);

    bool advanceReadPointer(qint64 amount);

    bool atEnd();

    bool reset();

    qint64 size();

protected:

    QByteArray* byteArray;

    qint64 currentPosition;

};

class QNonContiguousByteDeviceRingBufferImpl : public QNonContiguousByteDevice

{

public:

    QNonContiguousByteDeviceRingBufferImpl(QRingBuffer *rb);

    ~QNonContiguousByteDeviceRingBufferImpl();

    const char* readPointer(qint64 maximumLength, qint64 &len);

    bool advanceReadPointer(qint64 amount);

    bool atEnd();

    bool reset();

    qint64 size();

protected:

    QRingBuffer* ringBuffer;

    qint64 currentPosition;

};

class QNonContiguousByteDeviceIoDeviceImpl : public QNonContiguousByteDevice

{

public:

    QNonContiguousByteDeviceIoDeviceImpl(QIODevice *d);

    ~QNonContiguousByteDeviceIoDeviceImpl();

    const char* readPointer(qint64 maximumLength, qint64 &len);

    bool advanceReadPointer(qint64 amount);

    bool atEnd();

    bool reset();

    qint64 size();

protected:

    QIODevice* device;

    QByteArray* currentReadBuffer;

    qint64 currentReadBufferSize;

    qint64 currentReadBufferAmount;

    qint64 currentReadBufferPosition;

    qint64 totalAdvancements;

    bool eof;

    qint64 initialPosition;

};

class QNonContiguousByteDeviceBufferImpl : public QNonContiguousByteDevice

{

public:

    QNonContiguousByteDeviceBufferImpl(QBuffer *b);

    ~QNonContiguousByteDeviceBufferImpl();

    const char* readPointer(qint64 maximumLength, qint64 &len);

    bool advanceReadPointer(qint64 amount);

    bool atEnd();

    bool reset();

    qint64 size();

protected:

    QBuffer* buffer;

    QByteArray byteArray;

    QNonContiguousByteDeviceByteArrayImpl* arrayImpl;

};

// ... and the reverse thing

class QByteDeviceWrappingIoDevice : public QIODevice

{

public:

    QByteDeviceWrappingIoDevice (QNonContiguousByteDevice *bd);

    ~QByteDeviceWrappingIoDevice ();

    virtual bool isSequential () const;

    virtual bool atEnd () const;

    virtual bool reset ();

    virtual qint64 size () const;

protected:

     virtual qint64 readData ( char * data, qint64 maxSize );

     virtual qint64 writeData ( const char * data, qint64 maxSize );

     QNonContiguousByteDevice *byteDevice;

};

QT_END_NAMESPACE

#endif