// INBUF.H
//
// Copyright (c) 1997-1999 Symbian Ltd.  All rights reserved.
//

#if !defined(__INBUF_H__)
#define __INBUF_H__

#if !defined(__F32FILE_H__)
#include <f32file.h>
#endif

#if !defined(__S32STOR_H__)
#include <s32stor.h>
#endif

const TInt KErrEndOfInput = -1000;

class CImportBufferBase : public CBase
	{
	// The purpose of this class is to provide a method of
	// abstracting the source of an input through a buffer
	// The class is intended to be used for a single input then destroyed
public:
	IMPORT_C CImportBufferBase(TInt aMaxSize);
	IMPORT_C ~CImportBufferBase();
	IMPORT_C void ConstructL();
	IMPORT_C TInt ReadL(TText8& aByte);
	// !! Descriptor versions of ReadL useful?
	IMPORT_C virtual TInt SeekL(TSeek aSeekMode, TInt anOffset);
	IMPORT_C void ResetImportBuffer();
	IMPORT_C void ResetReadPtr();
protected:
	IMPORT_C virtual TInt FillImportBuf()=0;
	IMPORT_C TInt MaxSize();
	IMPORT_C void SetLength(TInt aLength);
protected:
	TInt iImportBufferLength; 
	HBufC8* iImportBuffer;
private:
	TText8* iReadPtr;
	TText8* iEndBuf;
	TText8* iTBase;
	TInt iMaxSize;
	};

class CFileImportBuffer : public CImportBufferBase
	{
	// Buffered import from a file
public:
	IMPORT_C CFileImportBuffer(RFile aSource, TInt aMaxSize);
	IMPORT_C TInt SeekL(TSeek aSeekMode, TInt anOffset);
protected:
	IMPORT_C TInt FillImportBuf();
private:
	RFile iSource;
	};

#endif // __INBUF_H__