--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/persistentstorage/store/USTRM/US_FLTR.CPP	Fri Jan 22 11:06:30 2010 +0200
@@ -0,0 +1,127 @@
+// Copyright (c) 1998-2009 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:
+//
+
+#include "US_STD.H"
+
+EXPORT_C TStreamFilter::TStreamFilter()
+	: iHost(NULL),iMode(0)
+/** Constructs an empty stream filter object. */
+	{}
+
+EXPORT_C void TStreamFilter::EmitL(const TAny* aPtr,TInt aLength)
+/** Writes data from the specified memory location directly to the host without 
+filtering.
+
+This is useful for sending any final data, when flushing the filter as part 
+of DoSynchL().
+
+In debug mode: the filter must be in write mode, otherwise the function raises 
+a STORE-Stream 11 panic. 
+
+In debug mode, a host stream must have been set before calling this function, 
+otherwise it raises a STORE-Stream 0 panic.
+
+@param aPtr A pointer to the memory location from which data is to be written 
+to the host stream.
+@param aLength The number of bytes to be written.
+@see DoSynchL() */
+	{
+	__ASSERT_DEBUG(iMode&EWrite,Panic(EStreamCannotWrite));
+	__ASSERT_DEBUG(iHost!=NULL,Panic(EStreamNotOpen));
+	iHost->WriteL(aPtr,aLength);
+	}
+
+EXPORT_C void TStreamFilter::DoRelease()
+/** Frees the host stream's resources.
+
+@see MStreamBuf::DoRelease() */
+	{
+	if (iHost!=NULL&&(iMode&EAttached))
+		iHost->Release();
+	iHost=NULL;
+	}
+
+EXPORT_C void TStreamFilter::DoSynchL()
+/** Synchronizes the host's intermediate buffer with its stream, leaving if any 
+error occurs.
+
+@see MStreamBuf::DoSynchL() */
+	{
+	if (iHost!=NULL&&(iMode&EAttached))
+		iHost->SynchL();
+	}
+
+EXPORT_C TInt TStreamFilter::DoReadL(TAny* aPtr,TInt aMaxLength)
+/** Reads data from the host stream through the filter into the specified memory 
+location.
+
+In debug mode: the filter must be in read mode, otherwise the function raises 
+a STORE-Stream 10 panic.
+
+In debug mode, a host stream must have been set before calling this function, 
+otherwise it raises a STORE-Stream 0 panic.
+
+@param aPtr A pointer to the target memory location for the filtered data.
+@param aMaxLength The maximum number of bytes to be read. In debug mode: if 
+this value is negative then the function raises a STORE-Stream 1 panic; if 
+this value is zero, then the function raises a STORE-Stream 3 panic.
+@return The number of bytes read. */
+	{
+	__ASSERT_DEBUG(aMaxLength>=0,Panic(EStreamReadLengthNegative));
+	__ASSERT_DEBUG(aMaxLength>0,Panic(EStreamReadNoTransfer));
+	__ASSERT_DEBUG(iMode&ERead,Panic(EStreamCannotRead));
+	__ASSERT_DEBUG(iHost!=NULL,Panic(EStreamNotOpen));
+	TFilterInput input(*this,aPtr,aMaxLength);
+	do
+		{
+		iHost->ReadL(input);
+		} while (!(input.Done()||input.Eof()));
+	return aMaxLength-input.Left();
+	}
+
+EXPORT_C void TStreamFilter::DoWriteL(const TAny* aPtr,TInt aLength)
+/** Writes data to the host stream through the filter from the specified memory 
+location.
+
+In debug mode: the filter must be in write mode, otherwise the function raises 
+a STORE-Stream 11 panic.
+
+In debug mode, a host stream must have been set before calling this function, 
+otherwise it raises a STORE-Stream 0 panic.
+
+@param aPtr A pointer to the source memory location.
+@param aLength The number of bytes to be written. In debug mode: if this value 
+is negative then the function raises a STORE-Stream 1 panic; if this value 
+is zero, then the function raises a STORE-Stream 7 panic. */
+	{
+	__ASSERT_DEBUG(aLength>=0,Panic(EStreamWriteLengthNegative));
+	__ASSERT_DEBUG(aLength>0,Panic(EStreamWriteNoTransfer));
+	__ASSERT_DEBUG(iMode&EWrite,Panic(EStreamCannotWrite));
+	__ASSERT_DEBUG(iHost!=NULL,Panic(EStreamNotOpen));
+	TFilterOutput output(*this,aPtr,aLength);
+	do
+		{
+		iHost->WriteL(output);
+		} while (!output.Done());
+	}
+
+EXPORT_C void TStreamFilter::__DbgChkMode(TInt aMode)
+//
+// Check mode allows either reading or writing, but not both.
+//
+	{
+	__ASSERT_ALWAYS((aMode&(ERead|EWrite))&&(aMode&(ERead|EWrite))!=(ERead|EWrite),Panic(EStreamModeInvalid));
+	}
+