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    41 

    42 #ifndef QNONCONTIGUOUSBYTEDEVICE_H

    43 #define QNONCONTIGUOUSBYTEDEVICE_H

    44 

    45 //

    46 //  W A R N I N G

    47 //  -------------

    48 //

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

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

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

    52 //

    53 // We mean it.

    54 //

    55 

    56 #include <QtCore/qobject.h>

    57 #include <QtCore/qbytearray.h>

    58 #include <QtCore/qbuffer.h>

    59 #include <QtCore/qiodevice.h>

    60 #include "private/qringbuffer_p.h"

    61 

    62 QT_BEGIN_NAMESPACE

    63 

    64 class Q_CORE_EXPORT QNonContiguousByteDevice : public QObject

    65 {

    66     Q_OBJECT

    67 public:

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

    69     virtual bool advanceReadPointer(qint64 amount) = 0;

    70     virtual bool atEnd() = 0;

    71     virtual bool reset() = 0;

    72     void disableReset();

    73     virtual qint64 size() = 0;

    74 

    75     virtual ~QNonContiguousByteDevice();

    76 

    77 protected:

    78     QNonContiguousByteDevice();

    79 

    80 

    81     bool resetDisabled;

    82 Q_SIGNALS:

    83     void readyRead();

    84     void readProgress(qint64 current, qint64 total);

    85 };

    86 

    87 class Q_CORE_EXPORT QNonContiguousByteDeviceFactory

    88 {

    89 public:

    90     static QNonContiguousByteDevice* create(QIODevice *device);

    91     static QNonContiguousByteDevice* create(QByteArray *byteArray);

    92     static QNonContiguousByteDevice* create(QRingBuffer *ringBuffer);

    93     static QIODevice* wrap(QNonContiguousByteDevice* byteDevice);

    94 };

    95 

    96 // the actual implementations

    97 //

    98 

    99 class QNonContiguousByteDeviceByteArrayImpl : public QNonContiguousByteDevice

   100 {

   101 public:

   102     QNonContiguousByteDeviceByteArrayImpl(QByteArray *ba);

   103     ~QNonContiguousByteDeviceByteArrayImpl();

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

   105     bool advanceReadPointer(qint64 amount);

   106     bool atEnd();

   107     bool reset();

   108     qint64 size();

   109 protected:

   110     QByteArray* byteArray;

   111     qint64 currentPosition;

   112 };

   113 

   114 class QNonContiguousByteDeviceRingBufferImpl : public QNonContiguousByteDevice

   115 {

   116 public:

   117     QNonContiguousByteDeviceRingBufferImpl(QRingBuffer *rb);

   118     ~QNonContiguousByteDeviceRingBufferImpl();

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

   120     bool advanceReadPointer(qint64 amount);

   121     bool atEnd();

   122     bool reset();

   123     qint64 size();

   124 protected:

   125     QRingBuffer* ringBuffer;

   126     qint64 currentPosition;

   127 };

   128 

   129 

   130 class QNonContiguousByteDeviceIoDeviceImpl : public QNonContiguousByteDevice

   131 {

   132 public:

   133     QNonContiguousByteDeviceIoDeviceImpl(QIODevice *d);

   134     ~QNonContiguousByteDeviceIoDeviceImpl();

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

   136     bool advanceReadPointer(qint64 amount);

   137     bool atEnd();

   138     bool reset();

   139     qint64 size();

   140 protected:

   141     QIODevice* device;

   142     QByteArray* currentReadBuffer;

   143     qint64 currentReadBufferSize;

   144     qint64 currentReadBufferAmount;

   145     qint64 currentReadBufferPosition;

   146     qint64 totalAdvancements;

   147     bool eof;

   148     qint64 initialPosition;

   149 };

   150 

   151 class QNonContiguousByteDeviceBufferImpl : public QNonContiguousByteDevice

   152 {

   153 public:

   154     QNonContiguousByteDeviceBufferImpl(QBuffer *b);

   155     ~QNonContiguousByteDeviceBufferImpl();

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

   157     bool advanceReadPointer(qint64 amount);

   158     bool atEnd();

   159     bool reset();

   160     qint64 size();

   161 protected:

   162     QBuffer* buffer;

   163     QByteArray byteArray;

   164     QNonContiguousByteDeviceByteArrayImpl* arrayImpl;

   165 };

   166 

   167 // ... and the reverse thing

   168 class QByteDeviceWrappingIoDevice : public QIODevice

   169 {

   170 public:

   171     QByteDeviceWrappingIoDevice (QNonContiguousByteDevice *bd);

   172     ~QByteDeviceWrappingIoDevice ();

   173     virtual bool isSequential () const;

   174     virtual bool atEnd () const;

   175     virtual bool reset ();

   176     virtual qint64 size () const;

   177 protected:

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

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

   180 

   181      QNonContiguousByteDevice *byteDevice;

   182 };

   183 

   184 QT_END_NAMESPACE

   185 

   186 #endif