// Copyright (c) 2005-2009 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

 @released

*/

#include <elements/interfacetable.h>

#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_ElemNetIntfIntrf, "ElemNetIntfIntrf");

#endif

using namespace NetInterfaces;

_LIT(KNetInterfacesPanic, "NetInterfaces");

enum TNetInterfacesPanic

	{

	EInterfaceNotFound = 0,

	};

EXPORT_C TAny* TInterfaceControl::FetchInterfaceL(TInt aInterfaceId)

	{

	TAny* itf = DoFetchInterface(aInterfaceId);

	if(itf == NULL)

		{

		//Since we do not have control over 3rd party code we only check

		//and mask this error as KErrNotSupported rather than panic ESockSvr

		//(we panic in UDEB, please see DoFetchInterface);

		User::Leave(KErrInterfaceNotSupported);

		}

	return itf;

	}

EXPORT_C TAny* TInterfaceControl::FetchInterface(TInt aInterfaceId)

	{

	TAny* itf = DoFetchInterface(aInterfaceId);

	if(itf == NULL)

		{

		// This is fatal.  Either an TInterfaceControl was returned for a

		// particular interface id and the TInterfaceControl was inconsistent, 

		// or a bad interface id was passed into FetchInterface.

		User::Panic(KNetInterfacesPanic, EInterfaceNotFound);

		}

	return itf;

	}

TAny* TInterfaceControl::DoFetchInterface(TInt aInterfaceId)

	{

	const TFIEntry* head = iHead;

	// Find the interface implementer

	while((head != NULL) && (head->iIfId != aInterfaceId))

		{

		head = head->iNextFn();

		}

	// If not found, aInterfaceId is not valid, leave with KErrArgument

	TAny* iface = NULL;

	if(head != NULL)

		{

		// Ask the implementer for the interface reference (pointer)

		iface = head->iFetchFnL(this);

		//The returned pointer cannot be NULL because it has been returned from a leaving function.

		//This may be the case in one scenario, where the API extension implementer (TInterfaceControl

		//derived object) has returned NULL from ReturnInterfacePtrL() which is a bug.

		__ASSERT_DEBUG(iface,User::Panic(KNetInterfacesPanic, EInterfaceNotFound));

		}

	return iface;

	}

EXPORT_C TInterfaceIter::TInterfaceIter(const TInterfaceControl& aItfControl)

:	iItfControl(aItfControl),

	iCurrent(aItfControl.iHead)

	{

	}

EXPORT_C TAny* TInterfaceIter::operator[](TInt aInd)

	{

	//aInd>0 not yet supported!

	__ASSERT_ALWAYS(aInd==0, User::Panic(KNetInterfacesPanic, EInterfaceNotFound));

	const TInterfaceControl::TFIEntry* fetcher = iItfControl.iHead;

	return fetcher? fetcher->iFetchFnL(const_cast<TInterfaceControl*>(&iItfControl)) : NULL;

	}

EXPORT_C TAny* TInterfaceIter::Next()

	{

	// Initialise current to head or grab next interface in list

	if (iCurrent == NULL)

		return NULL;

	iCurrent = iCurrent->iNextFn();

	return iCurrent? iCurrent->iFetchFnL(const_cast<TInterfaceControl*>(&iItfControl)) : NULL;

	}

EXPORT_C TBool AApiExtBase::SupportsExtInterface(TInt aInterfaceId) const

    {

    TRAPD(ret,const_cast<AApiExtBase*>(this)->FetchExtInterfaceL(aInterfaceId));

    return ret == KErrNone;

    }

EXPORT_C TInterfaceControl* AApiExtBase::FetchExtInterfaceControlL(TInt aInterfaceId)

	{

	return DoFetchInterfaceControlL(aInterfaceId);

	}

EXPORT_C TAny* AApiExtBase::FetchExtInterfaceL(TInt aInterfaceId)

    {

    TInterfaceControl* tic = FetchExtInterfaceControlL(aInterfaceId);

    __ASSERT_DEBUG(tic, User::Panic(KSpecAssert_ElemNetIntfIntrf, 1));

    return tic->FetchInterfaceL(aInterfaceId);

    }

EXPORT_C TAny* AApiExtBase::FetchExtInterface(TInt aInterfaceId)

    {

    TInterfaceControl* tic = NULL;

    TRAP_IGNORE(tic = FetchExtInterfaceControlL(aInterfaceId));

    return tic? tic->FetchInterface(aInterfaceId) : NULL;

    }

EXPORT_C TInterfaceControl* AApiExtBase::DoFetchInterfaceControlL(TInt aInterfaceId)

	{

	(void)aInterfaceId;

	User::Leave(KErrInterfaceNotSupported);

	return NULL;

	}