williamr@2: // Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@4: // under the terms of "Eclipse Public License v1.0"
williamr@2: // which accompanies this distribution, and is available
williamr@4: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: // include\mmf\server\mmfdatabuffer.h
williamr@2: // 
williamr@2: //
williamr@2: 
williamr@2: 
williamr@2: #ifndef __MMF_SERVER_DATABUFFER_H__
williamr@2: #define __MMF_SERVER_DATABUFFER_H__
williamr@2: 
williamr@2: #include <e32base.h>
williamr@2: 
williamr@2: 
williamr@2: #include <mmf/server/mmfbuffer.h>
williamr@2: 
williamr@2: /** 
williamr@2: @publishedAll
williamr@2: @released
williamr@2: 
williamr@2: Default buffer size if none is specified.
williamr@2: */
williamr@2: static const TInt KMMFDataBufferDefaultBufferSize = 32;
williamr@2: 
williamr@2: /**
williamr@2: @publishedAll
williamr@2: @released
williamr@2: 
williamr@2: This class is an abstract class for databuffers that can be presented in the form of a descriptor.
williamr@2: A constructor is provided which instantiates a CMMFDescriptorBuffer buffer by default.
williamr@2: 
williamr@2: @see CMMFDescriptorBuffer
williamr@2: */
williamr@2: class CMMFDataBuffer : public CMMFBuffer
williamr@2: 	{
williamr@2: public:
williamr@2: 	IMPORT_C static CMMFDataBuffer* NewL();
williamr@2: 	IMPORT_C static CMMFDataBuffer* NewL(TInt aMaxBufferSize);
williamr@2: 	/**
williamr@2: 	Destructor.
williamr@2: 	*/
williamr@2: 	virtual ~CMMFDataBuffer() {};
williamr@2: 
williamr@2: 	/**
williamr@2: 	Returns a reference to the data contained in the buffer (non const version).
williamr@2: 
williamr@2: 	This is a virtual function that each derived class must implement.
williamr@2: 
williamr@2: 	@return A reference to the buffer.
williamr@2: 	*/
williamr@2: 	virtual TDes8& Data() = 0;
williamr@2: 
williamr@2: 	/**
williamr@2: 	Returns a reference to the data contained in the buffer (const version).
williamr@2: 
williamr@2: 	This is a virtual function that each derived class must implement.
williamr@2: 
williamr@2: 	@return A reference to the buffer.
williamr@2: 	*/
williamr@2: 	virtual const TDesC8& Data() const = 0;
williamr@2: 
williamr@2: 	/**
williamr@2: 	Returns the buffer size, in bytes.
williamr@2: 
williamr@2: 	This is a virtual function that each derived class must implement.
williamr@2: 
williamr@2: 	@return The buffer size in bytes.
williamr@2: 	*/
williamr@2: 	virtual TUint BufferSize() const = 0;
williamr@2: 
williamr@2: 	/**
williamr@2: 	Sets the request size. 
williamr@2: 
williamr@2: 	Used where a component, such as a data source,
williamr@2: 	may not be able to write to the entire maximum length of the buffer
williamr@2: 	(variable bit rate codecs for example).
williamr@2: 
williamr@2: 	This is a virtual function that each derived class must implement.
williamr@2: 
williamr@2: 	@param  aSize
williamr@2: 	        The requested size, in bytes.
williamr@2: 	*/
williamr@2: 	virtual void SetRequestSizeL(TInt aSize) = 0;
williamr@2: protected:
williamr@2: 	/**
williamr@2: 	Protected constructor.
williamr@2: 	*/
williamr@2: 	CMMFDataBuffer(TUid aType): CMMFBuffer(aType) {};
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2: @publishedAll
williamr@2: @released
williamr@2: 
williamr@2: This class is a wrapper class to give a descriptor the same API as a CMMFDataBuffer.
williamr@2: 
williamr@2: The purpose of this class is that components such as codecs can use CMMFDataBuffers transparently
williamr@2: without having to be concerned with whether the buffer is a descriptor buffer
williamr@2: or a transfer buffer.
williamr@2: */
williamr@2: class CMMFDescriptorBuffer : public CMMFDataBuffer
williamr@2: 	{
williamr@2: public:
williamr@2: 	IMPORT_C static CMMFDescriptorBuffer* NewL();
williamr@2: 	IMPORT_C static CMMFDescriptorBuffer* NewL(TInt aMaxBufferSize);
williamr@2: 	IMPORT_C ~CMMFDescriptorBuffer();
williamr@2: 	IMPORT_C void ReAllocBufferL(TInt aMaxBufferSize);
williamr@2: 	virtual TDes8& Data();
williamr@2: 	virtual const TDesC8& Data() const;
williamr@2: 	virtual void SetStatus(TBufferStatus aStatus);
williamr@2: 	virtual void SetRequestSizeL(TInt aSize);
williamr@2: 	virtual TUint BufferSize() const;
williamr@2: 	virtual void SetPosition (TUint aPosition);
williamr@2: private:
williamr@2: 	CMMFDescriptorBuffer() : CMMFDataBuffer(KUidMmfDescriptorBuffer), iPtr(0,0,0) {};
williamr@2: 	void ConstructL(TInt aMaxBufferSize);
williamr@2: private:
williamr@2: 	TUint8* iData;
williamr@2: 	TPtr8 iPtr;
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2: @publishedAll
williamr@2: @released
williamr@2: 
williamr@2: This class is a wrapper class to give a transfer buffer/window the same API as a CMMFDataBuffer.
williamr@2: The purpose of this class is so that components such as codecs can use CMMFDataBuffers transparently
williamr@2: without having to be concerned with whether the buffer is a descriptor buffer
williamr@2: or a transfer buffer.
williamr@2: 
williamr@2: The class assumes that a valid RTransferWindow with a RTransferBuffer mapped in already exists.
williamr@2: 
williamr@2: Note:
williamr@2: CMMFTransferBuffers are not supported in EKA2.
williamr@2: */
williamr@2: 
williamr@2: 
williamr@2: class RTransferWindow
williamr@2: 	{
williamr@2: 	// dummy class
williamr@2: 	};
williamr@2: 	
williamr@2: 
williamr@2: class CMMFTransferBuffer : public CMMFDataBuffer
williamr@2: 	{
williamr@2: public:
williamr@2: 
williamr@2: 	IMPORT_C static CMMFTransferBuffer* NewL(RTransferWindow& aTransferWindow, TUint aDataLength = 0);
williamr@2: 	IMPORT_C ~CMMFTransferBuffer();
williamr@2: 	virtual TDes8& Data();
williamr@2: 	virtual const TDesC8& Data() const;
williamr@2: 	virtual TUint BufferSize() const;
williamr@2: 	virtual void SetRequestSizeL(TInt aSize);
williamr@2: 	virtual void SetPosition (TUint aPosition);
williamr@2: 	IMPORT_C RTransferWindow& TransferWindow();
williamr@2: 	IMPORT_C void MapOutBuffer();
williamr@2: 	IMPORT_C TInt UpdateTransferWindow(RTransferWindow& aTransferWindow, TUint aDataLength = 0);
williamr@2: 
williamr@2: private:
williamr@2: 	/**
williamr@2: 	Private constructor.
williamr@2: 	*/
williamr@2: 	CMMFTransferBuffer() : CMMFDataBuffer(KUidMmfTransferBuffer), iPtr(0,0,0){};
williamr@2: 	void ConstructL(RTransferWindow& aTransferWindow, TUint aDataLength);
williamr@2: 
williamr@2: private:
williamr@2: 	RTransferWindow iTransferWindow;
williamr@2: 	TBool iTransferWindowMappedInOK;
williamr@2: 	TPtr8 iPtr;
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2: @publishedAll
williamr@2: @released
williamr@2: 
williamr@2: This class is a wrapper class intended to provide support for shared I/O buffers under EKA2
williamr@2: This class, unlike other data buffers does not own memory - rather it contains a pointer to already allocated memory
williamr@2: The purpose of this class is that components such as codecs can use CMMFDataBuffers transparently
williamr@2: without having to be concerned with whether the buffer is a standard buffer or memory residing in shared I/O
williamr@2: 
williamr@2: Users of this class need to be very careful when using buffers of this type.
williamr@2: It cannot be assumed that a buffer of this type can be written/read by any process other than the current one - example - handing CMMFPtrBuffer to the file server may not work since the file server's process may not have access to write data buffer.
williamr@2: */
williamr@2: class CMMFPtrBuffer : public CMMFDataBuffer
williamr@2: 	{
williamr@2: public:
williamr@2: 	IMPORT_C static CMMFPtrBuffer* NewL();		//unitialised, pointer will be set via SetPtr
williamr@2: 	IMPORT_C static CMMFPtrBuffer* NewL(const TPtr8& aPtr);
williamr@2: 	IMPORT_C ~CMMFPtrBuffer();
williamr@2: 	IMPORT_C void SetPtr(const TPtr8& aPtr);
williamr@2: 	virtual TDes8& Data();
williamr@2: 	virtual const TDesC8& Data() const;
williamr@2: 	virtual void SetStatus(TBufferStatus aStatus);	
williamr@2: 	virtual void SetRequestSizeL(TInt aSize);
williamr@2: 	virtual TUint BufferSize() const;
williamr@2: 	virtual void SetPosition (TUint aPosition);
williamr@2: private:
williamr@2: 	CMMFPtrBuffer() : CMMFDataBuffer(KUidMmfPtrBuffer), iPtr(0,0,0) {};
williamr@2: 	void ConstructL(const TPtr8& aPtr);
williamr@2: private:
williamr@2: 	TPtr8 iPtr;
williamr@2: 	};
williamr@2: 
williamr@2: #endif