limitedstreams.h

7-Zip 是一款号称有着现今最高压缩比的压缩软件

// LimitedStreams.h

#ifndef __LIMITEDSTREAMS_H
#define __LIMITEDSTREAMS_H

#include "../../Common/MyCom.h"
#include "../IStream.h"

class CLimitedSequentialInStream:
  public ISequentialInStream,
  public CMyUnknownImp
{
  CMyComPtr<ISequentialInStream> _stream;
  UInt64 _size;
  UInt64 _pos;
  bool _wasFinished;
public:
  void SetStream(ISequentialInStream *stream) { _stream = stream; }
  void Init(UInt64 streamSize)
  {
    _size = streamSize;
    _pos = 0;
    _wasFinished = false;
  }
 
  MY_UNKNOWN_IMP

  STDMETHOD(Read)(void *data, UInt32 size, UInt32 *processedSize);
  UInt64 GetSize() const { return _pos; }
  bool WasFinished() const { return _wasFinished; }
};

class CLimitedSequentialOutStream:
  public ISequentialOutStream,
  public CMyUnknownImp
{
  CMyComPtr<ISequentialOutStream> _stream;
  UInt64 _size;
  bool _overflow;
public:
  MY_UNKNOWN_IMP
  STDMETHOD(Write)(const void *data, UInt32 size, UInt32 *processedSize);
  void SetStream(ISequentialOutStream *stream) { _stream = stream; }
  void ReleaseStream() { _stream.Release(); }
  void Init(UInt64 size)
  {
    _size = size;
    _overflow = false;
  }
  bool IsFinishedOK() const { return (_size == 0 && !_overflow); }
  UInt64 GetRem() const { return _size; }
};

#endif