sl@0: // Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // Written by Brendan, Dec 1996
sl@0: // Library associated files for pluggable components
sl@0: // 
sl@0: //
sl@0: 
sl@0: #if !defined(__LIBASSOC_H__)
sl@0: #define __LIBASSOC_H__
sl@0: #if !defined(__F32FILE_H__)
sl@0: #include <f32file.h>
sl@0: #endif
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: class TLibAssocBase
sl@0: /**
sl@0: @publishedAll
sl@0: @released
sl@0: 
sl@0: This is an implementation base class for TLibAssoc.
sl@0: */
sl@0: 	{
sl@0: protected:
sl@0: 	inline TLibAssocBase();
sl@0: 	IMPORT_C TLibAssocBase(const RLibrary& aLib,TAny* aPtr);
sl@0: 	IMPORT_C void Set(const RLibrary& aLib,TAny* aPtr);
sl@0: 	IMPORT_C static void DoUnload(TAny* aThis);
sl@0: public:
sl@0: 	inline TBool IsNull() const;
sl@0: private:
sl@0: 	RLibrary iLibrary;
sl@0: protected:
sl@0: 
sl@0:     /**
sl@0:     A Pointer to the class instance.
sl@0:     */
sl@0: 	TAny* iPtr;
sl@0: 	};
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: //	class TLibAssoc inlines
sl@0: inline TLibAssocBase::TLibAssocBase()
sl@0: 	: iPtr(NULL)
sl@0: /**
sl@0: Default constructor.
sl@0: 
sl@0: It sets the member TLibAssocBase::iPtr to NULL.
sl@0: */	
sl@0: 	{}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: inline TBool TLibAssocBase::IsNull() const
sl@0: /**
sl@0: Tests whether the pointer to the class instance is NULL.
sl@0: 
sl@0: @return ETrue, if the pointer is NULL; EFalse, otherwise.
sl@0: */
sl@0: 	{return iPtr==NULL;}
sl@0: 
sl@0: 
sl@0: //
sl@0: //	class TLibAssoc
sl@0: //
sl@0: template <class T>
sl@0: class TLibAssoc : public TLibAssocBase
sl@0: /**
sl@0: @publishedAll
sl@0: @released
sl@0: 
sl@0: Associates a dynamically loadable DLL and an instance of a class that,
sl@0: typically, will have been created using the ordinal 1 function of that DLL.
sl@0: 
sl@0: An object of this type is useful when cleanup behaviour requires that
sl@0: a class instance be deleted and the associated DLL be closed.
sl@0: 
sl@0: The DLL is expected to be already open when the TLibAssoc object is created.
sl@0: */
sl@0: 	{
sl@0: public:
sl@0: 	inline TLibAssoc();
sl@0: 	inline TLibAssoc(const RLibrary& aLib,T* aClass);
sl@0: 	inline void Set(const RLibrary& aLib,T* aClass);
sl@0: 	//
sl@0: 	inline void Unload();
sl@0: 	//
sl@0: 	inline operator TCleanupItem();
sl@0: 	operator TLibAssoc*(); // undefined, but here to prevent accidental delete(TLibAssoc)
sl@0: 	//
sl@0: 	inline T* Ptr();
sl@0: 	inline const T* PtrC() const;
sl@0: 	//
sl@0: 	inline operator T*();
sl@0: 	inline operator const T*() const;
sl@0: 	//
sl@0: 	inline T* operator->();
sl@0: 	inline const T* operator->() const;
sl@0: private:
sl@0: 	static void Cleanup(TAny* aThis); // for TCleanupOperation
sl@0: 	};
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline TLibAssoc<T>::TLibAssoc()
sl@0: /**
sl@0: Default constructor.
sl@0: 
sl@0: An association between a DLL and a class instance can be made
sl@0: after construction using the Set() function.
sl@0: */
sl@0: 	{}
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline TLibAssoc<T>::TLibAssoc(const RLibrary& aLib,T* aClass)
sl@0: 	: TLibAssocBase(aLib,aClass)
sl@0: /**
sl@0: Constructs the object taking the specified DLL and an instance of
sl@0: the specified class.
sl@0: 
sl@0: @param aLib   A reference to a DLL that has already been opened.
sl@0: @param aClass A pointer to an object to be associated with the DLL.
sl@0:               Typically, this object will have been created using
sl@0:               the ordinal 1 function from that DLL.
sl@0: */	
sl@0: 	{}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline void TLibAssoc<T>::Set(const RLibrary& aLib,T* aClass)
sl@0: /**
sl@0: Makes an association between the specified DLL and an instance of
sl@0: the specified class.
sl@0: 
sl@0: @param aLib   A reference to a DLL that has already been opened.
sl@0: @param aClass A pointer to an object to be associated with the DLL.
sl@0:               Typically, this object will have been created using
sl@0:               the ordinal 1 function from that DLL.
sl@0: */
sl@0: 	{TLibAssocBase::Set(aLib,aClass);}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline T* TLibAssoc<T>::Ptr()
sl@0: /**
sl@0: Gets a pointer to the class instance.
sl@0: 
sl@0: @return A pointer to the class instance.
sl@0: */
sl@0: 	{return (T*)iPtr;}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline const T* TLibAssoc<T>::PtrC() const
sl@0: /**
sl@0: Gets a pointer to the const class instance.
sl@0: 
sl@0: @return A pointer to the const class instance.
sl@0: */
sl@0: 	{return (const T*)iPtr;}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline TLibAssoc<T>::operator T*()
sl@0: /**
sl@0: Conversion operator.
sl@0: 
sl@0: Invoked by the compiler when a TLibAssoc<T> type is passed to a function that
sl@0: is prototyped to take a T* type.
sl@0: */
sl@0: 	{return (T*)iPtr;}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline TLibAssoc<T>::operator const T*() const
sl@0: /**
sl@0: Const conversion operator.
sl@0: 
sl@0: Invoked by the compiler when a TLibAssoc<T> type is passed to a function that
sl@0: is prototyped to take a const T* type.
sl@0: */
sl@0: 	{return (const T*)iPtr;}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline T* TLibAssoc<T>::operator->()
sl@0: /**
sl@0: Dereferencing operator.
sl@0: 
sl@0: @return A pointer to the class instance.
sl@0: */
sl@0: 	{return (T*)iPtr;}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline const T* TLibAssoc<T>::operator->() const
sl@0: /**
sl@0: Const dereferencing operator.
sl@0: 
sl@0: @return A pointer to the const class instance.
sl@0: */
sl@0: 	{return (const T*)iPtr;}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline TLibAssoc<T>::operator TCleanupItem()
sl@0: /**
sl@0: The TCleanupItem conversion operator.
sl@0: 
sl@0: Invoked by the compiler when a TLibAssoc<T> type is passed to a function that
sl@0: is prototyped to take a TCleanupItem type.
sl@0: 
sl@0: The most common usage is to put a cleanup item onto the cleanup stack using
sl@0: CleanupStack::PushL(). The cleanup operation is represented by the private
sl@0: static function Cleanup().
sl@0: 
sl@0: For example, if we declare
sl@0: 
sl@0: @code
sl@0: TLibAssoc<A> a;
sl@0: @endcode 
sl@0: 
sl@0: then we can simply put a cleanup item onto the cleanup stack
sl@0: by calling
sl@0: 
sl@0: @code
sl@0: CleanupStack::PushL(a);
sl@0: @endcode
sl@0: 
sl@0: @see TCleanupItem
sl@0: @see CleanupStack::PushL
sl@0: */
sl@0: 	{return(TCleanupItem(Cleanup,this));}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: inline void TLibAssoc<T>::Unload()
sl@0: /**
sl@0: Deletes the class instance and calls Close() on the associated DLL.
sl@0: 
sl@0: @see RLibrary::Close
sl@0: */
sl@0: 	{Cleanup(this);}
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: template <class T>
sl@0: void TLibAssoc<T>::Cleanup(TAny* aThis)
sl@0: /**
sl@0: The cleanup operation.
sl@0: 
sl@0: The implementation deletes the class instance and calls Close() on
sl@0: the associated DLL.
sl@0: 
sl@0: Note that this function is internal and is not intended for use; it is documented
sl@0: for completeness.
sl@0: */
sl@0: 	{
sl@0: 	delete (T*)(((TLibAssoc<T>*)aThis)->iPtr);
sl@0: 	TLibAssocBase::DoUnload(aThis);
sl@0: 	}
sl@0: 
sl@0: #endif