source: box/trunk/lib/common/ReadGatherStream.h @ 217

// --------------------------------------------------------------------------
//
// File
//              Name:    ReadGatherStream.h
//              Purpose: Build a stream (for reading only) out of a number of other streams.
//              Created: 10/12/03
//
// --------------------------------------------------------------------------

#ifndef READGATHERSTREAM_H
#define READGATHERSTREAM_H

#include "IOStream.h"

#include <vector>

// --------------------------------------------------------------------------
//
// Class
//              Name:    ReadGatherStream
//              Purpose: Build a stream (for reading only) out of a number of other streams.
//              Created: 10/12/03
//
// --------------------------------------------------------------------------
class ReadGatherStream : public IOStream
{
public:
        ReadGatherStream(bool DeleteComponentStreamsOnDestruction);
        ~ReadGatherStream();
private:
        ReadGatherStream(const ReadGatherStream &);
        ReadGatherStream &operator=(const ReadGatherStream &);
public:

        int AddComponent(IOStream *pStream);
        void AddBlock(int Component, pos_type Length, bool Seek = false, pos_type SeekTo = 0);

        virtual int Read(void *pBuffer, int NBytes, int Timeout = IOStream::TimeOutInfinite);
        virtual pos_type BytesLeftToRead();
        virtual void Write(const void *pBuffer, int NBytes);
        virtual bool StreamDataLeft();
        virtual bool StreamClosed();
        virtual pos_type GetPosition() const;

private:
        bool mDeleteComponentStreamsOnDestruction;
        std::vector<IOStream *> mComponents;
        
        typedef struct
        {
                pos_type mLength;
                pos_type mSeekTo;
                int mComponent;
                bool mSeek;
        } Block;
        
        std::vector<Block> mBlocks;
        
        pos_type mCurrentPosition;
        pos_type mTotalSize;
        unsigned int mCurrentBlock;
        pos_type mPositionInCurrentBlock;
        bool mSeekDoneForCurrent;
};


#endif // READGATHERSTREAM_H