backupandrestore/backupengine/inc/sbheapwrapper.h
changeset 0 d0791faffa3f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/backupandrestore/backupengine/inc/sbheapwrapper.h	Tue Feb 02 01:11:40 2010 +0200
@@ -0,0 +1,132 @@
+/**
+* Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+* Definition of CHeapWrapper and THeapWrapperHeader
+* 
+*
+*/
+
+
+
+/**
+ @file
+ @internalTechnology
+*/
+
+#ifndef __HEAPWRAPPER_H__
+#define __HEAPWRAPPER_H__
+
+#include <e32std.h>
+#include <connect/sbtypes.h>
+
+namespace conn
+	{
+	/** KMaxGenericTypeSize must be a multiple of 4 to ensure that all structures are 4-byte aligned 
+	@internalTechnology */
+	const TInt KMaxGenericTypeSize = 1024;
+	
+	class THeapWrapperHeader
+	/**
+	This class is packed at the beginning of the heap and stores information about the data
+	contained in the descriptor.
+	
+	Note that all structures in here must be 4-byte aligned, using dummy padding if necessary.
+	
+	@internalTechnology
+	*/
+		{
+	public:
+		inline TBool LockedFlag();
+		inline void SetLockedFlag(TBool aLockedFlag);
+		inline TBuf8<KMaxGenericTypeSize>& GenericTransferTypeBuffer();
+
+	public:
+		/** Finished flag, set to ETrue when the data in the descriptor 
+		is the last in a multi-part transfer*/
+		TBool iFinished;
+
+	private:
+		/** Flag to indicate that the heap has been locked for writing 
+		by an instance of CHeapWrapper */
+		TBool iLockedFlag;
+
+		/** Generic transfer type */
+		TBuf8<KMaxGenericTypeSize> iGenericDataTransferInfo;
+		};
+		
+	inline TBool THeapWrapperHeader::LockedFlag()
+	/** Getter for the private locked flag 
+	@return The status of the locked flag */
+		{
+		return iLockedFlag;
+		}
+		
+	inline void THeapWrapperHeader::SetLockedFlag(TBool aLockedFlag)
+	/** Setter for the locked flag
+	@param aLockedFlag The new state of the heap locked flag */
+		{
+		iLockedFlag = aLockedFlag;
+		}
+
+	inline TBuf8<KMaxGenericTypeSize>& THeapWrapperHeader::GenericTransferTypeBuffer()
+	/** Getter for the generic type buffer
+	@return Reference to generic type buffer
+	*/
+		{
+		return iGenericDataTransferInfo;
+		}
+
+	
+	// Offsets for defining pointers relative the the RChunk::Base() pointer
+
+	/** Offset for the lock flag */
+	const TInt KHeaderOffset = 0;
+	
+	/** Offset to the beginning of the main descriptor */
+	const TInt KDescriptorOffset = KHeaderOffset + sizeof(THeapWrapperHeader); // lock flag is 1 byte
+	
+	/** Offset to the data that the TPtr8 will point to */
+	const TInt KDataOffset = KDescriptorOffset + sizeof(TPtr8);
+	
+	class CHeapWrapper : public CBase
+	/**
+	This class is instantiated to ensure that data is passed over the Global Shared Heap 
+	by a common interface
+	
+	@internalTechnology
+	*/
+		{
+	public:
+		static CHeapWrapper* NewL();
+		TPtrC8& ReadBufferL(const RChunk& aChunk);
+		TPtr8& WriteBufferL(const RChunk& aChunk);
+		TInt ResetHeap(const RChunk& aChunk);
+		THeapWrapperHeader& Header(const RChunk& aChunk) const;
+
+		/** virtual C++ destructor */
+		~CHeapWrapper();
+	private:
+		/** C++ constructor initialises read buffer pointer to NULL*/
+		CHeapWrapper() : iReadBuf(NULL) {};
+
+		TPtr8& Buffer(const RChunk& aChunk);
+		void CleanReadBuffer();
+	private:
+		/** Pointer to the global buffer */
+		TPtrC8* iReadBuf; 
+		};
+
+	} // namespace conn
+
+#endif //__HEAPWRAPPER_H__