--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/commsfwsupport/commselements/virtualconstructors/src/vc.cpp	Thu Dec 17 09:22:25 2009 +0200
@@ -0,0 +1,201 @@
+// Copyright (c) 2007-2009 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:
+//
+
+/**
+ @file 
+ @internalTechnology
+*/
+
+#include "vc.h"
+
+#include <elements/vc.h>
+#include <elements/metadata.h> //Should we decouple STypeId from NetMeta (circular dependency)?
+
+
+#ifdef _DEBUG
+// Panic category for "absolutely impossible!" vanilla ASSERT()-type panics from this module
+// (if it could happen through user error then you should give it an explicit, documented, category + code)
+_LIT(KSpecAssert_ElemVirtualCtorv, "ElemVirtualCtorv");
+#endif
+
+using namespace Meta;
+using namespace VC;
+
+
+#ifdef _DEBUG
+	_LIT(KNetCtorPanic, "NetCtor");
+#endif
+enum TNetCtorPanic
+	{
+	EConstructorTableHasRepetitions = 0,
+	EConstructorTableIsNotSorted = 1
+	};
+
+const TInt KConstructorTableArrayGranularity = 8;
+
+EXPORT_C CVirtualCtorBase::CVirtualCtorBase()
+:	iCtorTableList(KConstructorTableArrayGranularity,_FOFF(TCtorTable,iInterfaceId))
+	{
+	}
+
+EXPORT_C CVirtualCtorBase::~CVirtualCtorBase()
+	{
+	iCtorTableList.Close();
+	}
+
+#if defined(_DEBUG)
+//This fn is only a debug mode helper function.
+//It may not:
+//1) be exported in a header file
+//2) be exported as IMPORT_C/EXPORT_C
+//3) modify the object being debugged in any way
+
+//We assume that elements of the array may never be NULL
+TBool __Debug_NoRepetitions(const TImplementationProxy* aFirstEntry, TInt aLength)
+	{
+	__ASSERT_DEBUG(aLength>=0, User::Panic(KSpecAssert_ElemVirtualCtorv, 1));
+
+	if (aLength<=1)
+		{
+		return ETrue;
+		}
+
+	for (TInt i = 0; i < aLength; ++i)
+		{
+		for (TInt j = i + 1; j < aLength; ++j)
+			{
+			if ((aFirstEntry+i)->iImplementationUid.iUid == (aFirstEntry+j)->iImplementationUid.iUid)
+				{
+				return EFalse;
+				}
+			}
+		}
+
+	return ETrue;
+	}
+
+//We assume that elements of the array may never be NULL
+TBool __Debug_IsSorted(const TImplementationProxy* aFirstEntry, TInt aLength)
+	{
+	__ASSERT_DEBUG(aLength>=0, User::Panic(KSpecAssert_ElemVirtualCtorv, 2));
+
+	if (aLength<=1)
+		{
+		return ETrue;
+		}
+
+	const TImplementationProxy* thisEntry = aFirstEntry + 1;
+
+	TReal trend = thisEntry->iImplementationUid.iUid - aFirstEntry->iImplementationUid.iUid;
+
+	for (TInt i = 1; i < aLength; ++i)
+		{
+		TReal next = (thisEntry++)->iImplementationUid.iUid;
+		TReal prev = (aFirstEntry++)->iImplementationUid.iUid;
+		if (((next - prev) * trend) < 0)
+			{
+			return EFalse;
+			}
+		}
+	return ETrue;
+	}
+#endif
+
+EXPORT_C void CVirtualCtorBase::RegisterInterfaceL(TUid aInterfaceId, TInt aNumCtors, const TImplementationProxy* aCtorTable)
+	{
+	TInt dummyIndex;
+	const TCtorTable* table = FindCtorTable(aInterfaceId, dummyIndex);
+	if(table != NULL)
+		{
+		table->iRegisteredCount++;
+		}
+	else
+		{
+		//Repetitions are not allowed. It is a serious programming mistake.
+		__ASSERT_DEBUG(__Debug_NoRepetitions(aCtorTable,aNumCtors), User::Panic(KNetCtorPanic, EConstructorTableHasRepetitions));
+
+		//The disadvantage of a binary search is that the array needs to be sorted
+		//(in this case at compile time) or there will be a significant speed penalty.
+
+		//We assert here (and not log only) to protect binary compatibility of future tables.
+		__ASSERT_DEBUG(__Debug_IsSorted(aCtorTable,aNumCtors), User::Panic(KNetCtorPanic, EConstructorTableIsNotSorted));
+
+		iCtorTableList.InsertInUnsignedKeyOrderL(TCtorTable(aInterfaceId, aNumCtors, aCtorTable));
+		}
+	}
+
+EXPORT_C void CVirtualCtorBase::DeregisterInterface(TUid aInterfaceId)
+	{
+	TInt index;
+	const TCtorTable* table = FindCtorTable(aInterfaceId, index);
+	if(table != NULL)
+		{
+		if(--(table->iRegisteredCount) == 0)
+			{
+			iCtorTableList.Remove(index);
+			}
+		}
+	}
+
+EXPORT_C TBool CVirtualCtorBase::IsInterfaceRegistered(TUid aInterfaceId) const
+	{
+	TInt idx;
+	const CVirtualCtorBase::TCtorTable* table = FindCtorTable(aInterfaceId,idx);
+	return table!=NULL;
+	}
+
+const CVirtualCtorBase::TCtorTable* CVirtualCtorBase::FindCtorTable(TUid aInterfaceId, TInt& aIndex) const
+	{
+	return (KErrNone==iCtorTableList.FindInUnsignedKeyOrder(TCtorTable(aInterfaceId,0,0),aIndex))? &iCtorTableList[aIndex] : NULL;
+	}
+
+EXPORT_C TProxyNewLPtr CVirtualCtorBase::FindRawCtor(const Meta::STypeId& aType) const
+	{
+	TInt aIndex;
+	const TCtorTable* ctorTable;
+	if((ctorTable = FindCtorTable(aType.iUid, aIndex)) != NULL)
+		{
+		//In our case the only advantage of binary search over linear search is speed.
+		//The number of comparisons required for a binary search on N lelments is on average log2(N),
+		//while for linear search it is obviously N/2.
+		//For example, for an array of 40 entries, binary search will on average require 6 comparisons
+		//against 20 for linear. For an array with 1000 entries the proportion is around 1%.
+
+		//For very small arrays the speed gain is insigniffcant, but we have decided that
+		//advantages from searching of even medium sized arrays compensate disadvantages related to
+		//forced sorting.
+
+		//Currently there is no support for binary search of const (compile time) arrays like TFixedArray.
+		//We use this "workaround" below to be able to use supported binary search on our const arrays.
+		TImplementationProxy* entries = const_cast<TImplementationProxy*>(ctorTable->iCtorTable);
+		RArray<TImplementationProxy> array(sizeof(TImplementationProxy),entries,ctorTable->iNumCtors);
+		TImplementationProxy tester = {aType.iType,NULL};
+		__ASSERT_COMPILE(_FOFF(TImplementationProxy,iImplementationUid)==0); //We rely on the fact that the key offset is 0
+		return (KErrNone==array.FindInUnsignedKeyOrder(tester,aIndex))? array[aIndex].iNewLFuncPtr : NULL;
+		}
+	return NULL;
+	}
+
+EXPORT_C TAny* CVirtualCtorInPlace::New(const Meta::STypeId& aType, TDes8& aBuff) const
+    {
+	TInPlaceNewPtr newFn = FindCtor(aType);
+	if(newFn)
+		{
+		return newFn(aBuff);
+		}
+	return NULL;
+    }
+
+