diff -r 000000000000 -r 2e3d3ce01487 contextframework/cfw/src/basicoperationsplugin/cfcontextoperation.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contextframework/cfw/src/basicoperationsplugin/cfcontextoperation.cpp	Tue Feb 02 10:12:00 2010 +0200
@@ -0,0 +1,247 @@
+/*
+* Copyright (c) 2002-2008 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:  CCFContextOperation class implementation.
+*
+*/
+
+
+// INCLUDES
+#include <f32file.h> // for KExtDelimiter '.' and KDriveDelimiter ':'
+
+#include "cfcontextoperation.h"
+#include "cfbasicoptrace.h"
+
+// CONSTANTS
+const TInt KCFContextOperationNoContextLevelDelay = 0;
+const TInt KDefaultPreviousValueLength = 256;
+
+// ======== MEMBER FUNCTIONS ========
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::CCFContextOperation
+// C++ default constructor can NOT contain any code, that might leave.
+// ---------------------------------------------------------------------------
+//
+CCFContextOperation::CCFContextOperation( MCFOperationServices& aServices,
+    CCFOperationNode* aParent,
+    HBufC* aType,
+    HBufC* aSource )
+    :   CCFOperationNode( aServices, aParent ),
+        iContextLevelDelay( 0 ),
+        iSource( aSource ),
+        iType( aType )
+    {
+    FUNC_LOG;
+
+    iPreviousValue = HBufC::New( KDefaultPreviousValueLength );
+    }
+
+
+// Destructor
+CCFContextOperation::~CCFContextOperation()
+    {
+    FUNC_LOG;
+
+    delete iSource;
+    delete iType;
+    delete iPreviousValue;
+    }
+
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::Evaluate
+// ---------------------------------------------------------------------------
+//
+TBool CCFContextOperation::Evaluate( const CCFContextObject& aContext,
+    TInt& aContextLevelDelay )
+    {
+    FUNC_LOG;
+
+    DOM_INFO( "CCFContextOperation::Evaluate" );
+
+    // Check that context value has changed (context is state information)
+    if ( iPreviousValue && ( *iPreviousValue ).Compare( aContext.Value() ) == 0 )
+        {
+        INFO_2( "CCFContextOperation::Evaluate - NOT evaluating (prev value [%S] == arg value [%S])!",
+            iPreviousValue, &aContext.Value() );
+        aContextLevelDelay = KCFContextOperationNoContextLevelDelay;
+        return EFalse;
+        }
+    TInt err = UpdatePreviousValue( aContext.Value() );
+    ERROR( err, "Previous value update failed!" );
+
+    // Ask concrete implementation if it is true
+    TInt val( EFalse );
+    TRAP( err, val = IsTrueL( aContext ) );
+
+    if ( err != KErrNone )
+        {
+        ERROR( err, "CCFContextOperation: IsTrueL leave occurred, evaluation cancelled" );
+        return EFalse;
+        }
+
+    // Evaluate parents if we have changed
+    if ( val != iValue )
+        {
+        INFO_1( "CCFContextOperation::Evaluate - Value changed to (-1=undefined, 0=false, 1=true): %d", val );
+
+        iValue = static_cast< TCFConditionValue >( val );
+        if ( iParent )
+            {
+            iParent->Evaluate();
+            }
+        }
+    else
+        {
+        INFO_1( "CCFContextOperation::Evaluate - Value still (-1=undefined, 0=false, 1=true): %d", val );
+        }
+
+    aContextLevelDelay = iContextLevelDelay;
+    return ETrue;
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::Source
+// ---------------------------------------------------------------------------
+//
+TPtrC CCFContextOperation::Source() const
+    {
+    FUNC_LOG;
+
+    return TPtrC( *iSource );
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::Type
+// ---------------------------------------------------------------------------
+//
+TPtrC CCFContextOperation::Type() const
+    {
+    FUNC_LOG;
+
+    return TPtrC( *iType );
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::IsAllRequired
+// ---------------------------------------------------------------------------
+//
+TBool CCFContextOperation::IsAllRequired() const
+    {
+    FUNC_LOG;
+
+    return EFalse;
+    }
+
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::UpdatePreviousValue
+// ---------------------------------------------------------------------------
+//
+TInt CCFContextOperation::UpdatePreviousValue( const TDesC& aNewValue )
+    {
+    FUNC_LOG;
+
+    TInt err = KErrNone;
+    if( !iPreviousValue )
+        {
+        iPreviousValue = HBufC::New( KDefaultPreviousValueLength );
+        }
+
+    if( iPreviousValue )
+        {
+        TPtr previousValuePtr = iPreviousValue->Des();
+        if( previousValuePtr.MaxLength() >= aNewValue.Length() )
+            {
+            previousValuePtr.Copy( aNewValue );
+            }
+        else
+            {
+            delete iPreviousValue;
+            iPreviousValue = NULL;
+            iPreviousValue = aNewValue.Alloc();
+            if( !iPreviousValue )
+                {
+                err = KErrNoMemory;
+                }
+            }
+        }
+    else
+        {
+        err = KErrNoMemory;
+        }
+
+    return err;
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::PreviousValue
+// ---------------------------------------------------------------------------
+//
+const TDesC& CCFContextOperation::PreviousValue()
+    {
+    if ( iPreviousValue )
+        {
+        return *iPreviousValue;
+        }
+    return KNullDesC;
+    }
+
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::ActivateL
+// ---------------------------------------------------------------------------
+//
+void CCFContextOperation::ActivateL()
+    {
+    FUNC_LOG;
+
+    iServices.SubscribeContextL( this );
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::Deactivate
+// ---------------------------------------------------------------------------
+//
+void CCFContextOperation::Deactivate()
+    {
+    FUNC_LOG;
+
+    iServices.RemoveSubscription( this );
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::CheckSecurity
+// ---------------------------------------------------------------------------
+//
+TInt CCFContextOperation::CheckSecurity()
+    {
+    FUNC_LOG;
+
+    if ( !iSource || !iType )
+        {
+        return KErrBadDescriptor;
+        }
+
+    return iServices.CheckContextReadSecurity( *iSource, *iType );
+    }
+
+// ---------------------------------------------------------------------------
+// CCFContextOperation::Evaluate
+// ---------------------------------------------------------------------------
+//
+void CCFContextOperation::Evaluate()
+    {
+    FUNC_LOG;
+    }