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#ifndef CHUNKS_H
#define CHUNKS_H
/** \cond docNever */
/*! The Chunks class is the storage backend for QHexEdit.
*
* When QHexEdit loads data, Chunks access them using a QIODevice interface. When the app uses
* a QByteArray interface, QBuffer is used to provide again a QIODevice like interface. No data
* will be changed, therefore Chunks opens the QIODevice in QIODevice::ReadOnly mode. After every
* access Chunks closes the QIODevice, that's why external applications can overwrite files while
* QHexEdit shows them.
*
* When the the user starts to edit the data, Chunks creates a local copy of a chunk of data (4
* kilobytes) and notes all changes there. Parallel to that chunk, there is a second chunk,
* which keep track of which bytes are changed and which not.
*
*/
#include <QtCore>
struct Chunk
{
QByteArray data;
QByteArray dataChanged;
qint64 absPos;
};
class Chunks: public QObject
{
Q_OBJECT
public:
// Constructors and file settings
Chunks(QObject *parent);
Chunks(QIODevice &ioDevice, QObject *parent);
bool setIODevice(QIODevice &ioDevice);
// Getting data out of Chunks
QByteArray data(qint64 pos=0, qint64 count=-1, QByteArray *highlighted=0);
bool write(QIODevice &iODevice, qint64 pos=0, qint64 count=-1);
// Set and get highlighting infos
void setDataChanged(qint64 pos, bool dataChanged);
bool dataChanged(qint64 pos);
// Search API
qint64 indexOf(const QByteArray &ba, qint64 from);
qint64 lastIndexOf(const QByteArray &ba, qint64 from);
// Char manipulations
bool insert(qint64 pos, char b);
bool overwrite(qint64 pos, char b);
bool removeAt(qint64 pos);
// Utility functions
char operator[](qint64 pos);
qint64 pos();
qint64 size();
private:
int getChunkIndex(qint64 absPos);
QIODevice * _ioDevice;
qint64 _pos;
qint64 _size;
QList<Chunk> _chunks;
#ifdef MODUL_TEST
public:
int chunkSize();
#endif
};
/** \endcond docNever */
#endif // CHUNKS_H
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