filemanager.h Example File

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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() override;

  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