chbffile.h

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C头文件 代码 · 共 70 行

/****************************************************************************
*
*                            Open Watcom Project
*
*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
*  ========================================================================
*
*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
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*    except in compliance with the License. BY USING THIS FILE YOU AGREE TO
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* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
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****************************************************************************/


#ifndef __CHBFFILE_H__

// disable "integral value may be truncated" warning
#pragma warning 389 9

#include <wstd.h>
#include "chfile.h"
#include "mempool.h"

class CheckedBufferedFile : public CheckedFile {
public:

                    CheckedBufferedFile( const char * fileName );
    virtual         ~CheckedBufferedFile();

    virtual void    open( int access, int permission );
    virtual int     read( void * buffer, int len );
    virtual void    write( const void * buffer, int len );
    virtual long    seek( long offset, int whence );
    virtual long    tell() const;

protected:
    virtual void    reOpen();
    virtual void    privClose();
            void    flushBuffer();      // empty write buffer
            void    reloadBuffer();

            char *      _buffer;
            int         _bufLen;        // the number of bytes in the buffer
            long        _startOffset;   // offset for start of buffer in file
            int         _buffOffset;    // offset within buffer

    static  MemoryPool  _bufferPool;
};

#define __CHBFFILE_H__
#endif