filemanager.h Example File
network/torrent/filemanager.h

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 #ifndef FILEMANAGER_H
 #define FILEMANAGER_H

 #include <QBitArray>
 #include <QList>
 #include <QMutex>
 #include <QThread>
 #include <QWaitCondition>

 #include "metainfo.h"

 class QByteArray;
 class QFile;
 class QTimerEvent;

 class FileManager : public QThread
 {
     Q_OBJECT

 public:
     FileManager(QObject *parent = 0);
     virtual ~FileManager();

     inline void setMetaInfo(const MetaInfo &info) { metaInfo = info; }
     inline void setDestinationFolder(const QString &directory) { destinationPath = directory; }

     int read(int pieceIndex, int offset, int length);
     void write(int pieceIndex, int offset, const QByteArray &data);
     void verifyPiece(int pieceIndex);
     inline qint64 totalSize() const { return totalLength; }

     inline int pieceCount() const { return numPieces; }
     int pieceLengthAt(int pieceIndex) const;

     QBitArray completedPieces() const;
     void setCompletedPieces(const QBitArray &pieces);

     QString errorString() const;

 public slots:
     void startDataVerification();

 signals:
     void dataRead(int id, int pieceIndex, int offset, const QByteArray &data);
     void error();
     void verificationProgress(int percent);
     void verificationDone();
     void pieceVerified(int pieceIndex, bool verified);

 protected:
     void run();

 private slots:
     bool verifySinglePiece(int pieceIndex);
     void wakeUp();

 private:
     bool generateFiles();
     QByteArray readBlock(int pieceIndex, int offset, int length);
     bool writeBlock(int pieceIndex, int offset, const QByteArray &data);
     void verifyFileContents();

     struct WriteRequest {
         int pieceIndex;
         int offset;
         QByteArray data;
     };
     struct ReadRequest {
         int pieceIndex;
         int offset;
         int length;
         int id;
     };

     QString errString;
     QString destinationPath;
     MetaInfo metaInfo;
     QList<QFile *> files;
     QList<QByteArray> sha1s;
     QBitArray verifiedPieces;

     bool newFile;
     int pieceLength;
     qint64 totalLength;
     int numPieces;
     int readId;
     bool startVerification;
     bool quit;
     bool wokeUp;

     QList<WriteRequest> writeRequests;
     QList<ReadRequest> readRequests;
     QList<int> pendingVerificationRequests;
     QList<int> newPendingVerificationRequests;
     QList<qint64> fileSizes;

     mutable QMutex mutex;
     mutable QWaitCondition cond;
 };

 #endif