imservices/imfeatureplugin/srcimdatamodel/imeventcodec.cpp
changeset 51 61fad867f68e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/imservices/imfeatureplugin/srcimdatamodel/imeventcodec.cpp	Wed Nov 03 09:32:20 2010 +0530
@@ -0,0 +1,251 @@
+/*
+* Copyright (c) 2007 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:  Base class for API implementations.
+*
+*/
+
+#include "imeventcodec.h"
+#include "imconversationeventimp.h"
+#include "ximpapieventbase.h"
+#include <s32strm.h>
+#include <s32mem.h>
+
+/**
+ * Type definition for exact API event constructor signature.
+ */
+typedef CXIMPApiEventBase* (*TApiEventConstructor)( RReadStream& );
+
+/**
+ * Structure for mapping event interface IDs to
+ * to corect API event constructors.
+ */
+struct SApiEventConstructorMap
+    {
+    //Interface id
+    TInt32    iInterfaceId;
+
+    //Function pointer to event interface implementation
+    TApiEventConstructor iConstructorPtr;
+    } ;
+
+/**
+ * Helper macro to initialise KApiEventConstructorTable members.
+ *
+ * Macro forces that each event implementation class to have static
+ * NewFromStreamLC() memeber function to instantiate the object.
+ *
+ * See TApiEventConstructor type definition for exact constructor
+ * signature.
+ */
+#define CONSTRUCTOR_ENTRY( TheImplementedIf, TheClass ) \
+    { TheImplementedIf::KInterfaceId, TheClass::NewFromStreamLC } \
+
+
+/**
+ * Constructor function mapping for event interface implementations.
+ *
+ * When new event types are implemented, add them here.
+ */
+
+const SApiEventConstructorMap KApiEventConstructorTable[] =
+    {
+		CONSTRUCTOR_ENTRY( MImConversationEvent, CImConversationEventImp ),
+    };
+
+
+/**
+ * Count of constructor mappings.
+ */
+const TInt KApiEventConstructorCount = sizeof( KApiEventConstructorTable )
+                                        / sizeof( SApiEventConstructorMap );
+
+
+
+// ============================ HELPER FUNCTIONS =============================
+
+
+/**
+ * Helper function to locate constructor function for
+ * event interface ID.
+ *
+ * @param aEventInterfaceId The event interface ID.
+ * @return Event object constructor function.
+ */
+TApiEventConstructor ConstructorForInterface( TInt32 aEventInterfaceId )
+    {
+    //Locate correct constructor
+    for( TInt ix = 0; ix < KApiEventConstructorCount; ix++ )
+        {
+     const SApiEventConstructorMap map = KApiEventConstructorTable[ ix ];
+        if( map.iInterfaceId == aEventInterfaceId )
+            {
+            return map.iConstructorPtr;
+            }  
+        }
+    return NULL;
+    }
+
+
+/**
+ * Helper function to instantiate new event object
+ * of requested type and construct it from the stream.
+ *
+ * @param aEventInterfaceId
+ * @return Event object constructor function.
+ */
+CXIMPApiEventBase* NewEventObjectFromStreamLC( TInt32 aEventInterfaceId,
+                                               RReadStream& aStream )
+    {
+    TApiEventConstructor newFromStreamLC = NULL;
+
+    //Locate correct constructor for interface ID
+    newFromStreamLC = ConstructorForInterface( aEventInterfaceId );
+
+    if( ! newFromStreamLC )
+	    {
+	    return 	NULL;
+	    }
+    //Instantiate the object
+    CXIMPApiEventBase* eventObject = newFromStreamLC( aStream );
+
+    return eventObject;    
+    }
+
+
+// ============================ MEMBER FUNCTIONS =============================
+
+
+// ---------------------------------------------------------------------------
+// CImEventCodec::NewL()
+// ---------------------------------------------------------------------------
+//
+CImEventCodec* CImEventCodec::NewL()
+    {
+    CImEventCodec* self = new( ELeave ) CImEventCodec() ;
+    CleanupStack::PushL( self );
+    self->ConstructL();
+    CleanupStack::Pop( self );
+    return self;
+    }
+
+
+// ---------------------------------------------------------------------------
+// CImEventCodec::ConstructL()
+// ---------------------------------------------------------------------------
+//
+void CImEventCodec::ConstructL()
+    {
+    }
+// ---------------------------------------------------------------------------
+// CImEventCodec::CImEventCodec()
+// ---------------------------------------------------------------------------
+//
+CImEventCodec::CImEventCodec()
+    {
+    }
+
+// ---------------------------------------------------------------------------
+// CImEventCodec::~CImEventCodec()
+// ---------------------------------------------------------------------------
+//
+CImEventCodec::~CImEventCodec()
+    {
+    }
+
+// ---------------------------------------------------------------------------
+// CImEventCodec::PackL()
+// ---------------------------------------------------------------------------
+//
+HBufC8* CImEventCodec::PackL( CXIMPApiEventBase& aEventObj,
+                                        TInt32& aTypeOfEvent )
+    {
+    CBufFlat* buffer = CBufFlat::NewL( 10 ); // initial granularity to 10
+    CleanupStack::PushL( buffer );
+
+    RBufWriteStream ws;
+    CleanupClosePushL( ws );
+    ws.Open( *buffer ); // CSI: 65 #
+
+    //Ask real event type through the event base interface
+    TInt32 eventIfId = aEventObj.Base().GetInterfaceId();
+
+    //And write both event type and data
+    ws.WriteInt32L( eventIfId );
+    aEventObj.ExternalizeL( ws );
+    ws.CommitL();
+    CleanupStack::PopAndDestroy();  //ws
+
+    HBufC8* heapBuf = buffer->Ptr( 0 ).AllocL();
+
+    CleanupStack::PopAndDestroy( buffer );
+
+
+    aTypeOfEvent = eventIfId;
+    return heapBuf;
+    }
+
+
+// ---------------------------------------------------------------------------
+// CImEventCodec::PackL()
+// ---------------------------------------------------------------------------
+//
+void CImEventCodec::PackL( CXIMPApiEventBase& aEventObj,
+                                     TInt32& aTypeOfEvent,
+                                     CBufFlat* aBuffer )
+    {
+    RBufWriteStream ws;
+    CleanupClosePushL( ws );
+    ws.Open( *aBuffer ); // CSI: 65 #
+
+    //Ask real event type through the event base interface
+    TInt32 eventIfId = aEventObj.Base().GetInterfaceId();
+
+    //And write both event type and data
+    ws.WriteInt32L( eventIfId );
+    aEventObj.ExternalizeL( ws );
+    ws.CommitL();
+    CleanupStack::PopAndDestroy( );  //ws
+    
+    aTypeOfEvent = eventIfId;
+    }
+
+
+// ---------------------------------------------------------------------------
+// CImEventCodec::UnPackL()
+// ---------------------------------------------------------------------------
+//
+CXIMPApiEventBase* CImEventCodec::UnPackL( const TDesC8& aEventData,
+                                                     TInt32& aTypeOfEvent )
+    {
+    RDesReadStream rs;
+    rs.Open( aEventData ); // CSI: 65 #
+    CleanupClosePushL( rs );
+
+    TInt32 eventIfId = rs.ReadInt32L();
+    CXIMPApiEventBase* eventObject = NewEventObjectFromStreamLC( eventIfId, rs );
+    if( eventObject )
+	    {
+	    CleanupStack::Pop( eventObject ); //eventObject	
+	    }
+    
+    CleanupStack::PopAndDestroy(  ); // rs
+
+
+    aTypeOfEvent = eventIfId;
+    return eventObject;
+    }
+
+
+// End of file
+