sl@0: // Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: //
sl@0: 
sl@0: #if !defined(__FILESTREAMBUF_H__)
sl@0: #define __FILESTREAMBUF_H__
sl@0: 
sl@0: #include <stdio.h>
sl@0: #include <pcstore/streamid.h>
sl@0: 
sl@0: namespace PCStore
sl@0: {
sl@0: class CDirectFileStore;
sl@0: 
sl@0: /**
sl@0: @internalComponent
sl@0:  
sl@0: A file stream buffer that provides I/O interfaces for streamed data.
sl@0: 
sl@0: This file stream buffer: 
sl@0: . is unbuffered: all data passed to it will immediately be written to the corresponding file
sl@0:   or returned to its caller.
sl@0: 
sl@0: . provides read or write capability: it opens the file in read or write mode. After it is 
sl@0:   instantiated, only read or write function can be called, depending on the file open mode. 
sl@0:   Exception will be thrown upon an unmatching call.
sl@0: 
sl@0: . is unseekable. It only moves the file pointer to the position represented by the stream id, 
sl@0:   which is passed to its constructor. In the subsequent read or write operations, the pointer 
sl@0:   always goes forward.
sl@0: 
sl@0: For each file store, one object of this class is created in the constructor of CDirectFileStore. 
sl@0: CDirectFileStore will pass the reference of this object to the stream it creates. In order to 
sl@0: ensure there is only one stream opened in any moment, streams will call the StreamOpen and 
sl@0: StreamClose methods respectively in their constructor and destructor to signal their open 
sl@0: and close.
sl@0: 
sl@0: @see CDirectFileStore 
sl@0: @see CStoreWriteStream
sl@0: @see CStoreReadStream
sl@0: */
sl@0: class CFileStreamBuf
sl@0: 	{
sl@0: public:
sl@0: 	//Enumerations for the file open mode
sl@0: 	enum TFileMode 
sl@0: 	{
sl@0: 	EReadFile=0,
sl@0: 	EWriteFile=1
sl@0: 	};
sl@0: 
sl@0: public:
sl@0: 	CFileStreamBuf(const char* aFileName, TFileMode aMode);
sl@0: 	~CFileStreamBuf();
sl@0: 	void StreamOpen(TStreamId aStreamId);
sl@0: 	void StreamClose();
sl@0: 	TStreamId GetNewStreamId();
sl@0: 	void Read(const TUint8* aPtr, TInt32 aLength);
sl@0: 	void Write(const TUint8* aPtr, TInt32 aLength);
sl@0: 
sl@0: private:
sl@0: 	CFileStreamBuf(const CFileStreamBuf& aBuf); 
sl@0: 	CFileStreamBuf& operator=(const CFileStreamBuf& aBuf); 
sl@0: 
sl@0: private:
sl@0: 	FILE* iFile;
sl@0: 	TBool iStreamOpened;
sl@0: 	};
sl@0: }
sl@0: #endif // !defined(__FILESTREAMBUF_H__)