Auxiliary elements simplifying work with Windows API.

Helper directives used during a construction of COM interfaces
The directives provide ability to reduce amount of code needed to define a COM interface and classes that implement it. An example below shows using these definitions in order to define a pair of structures, where the Class1 structure defines the QueryInterface method inplace, and the Class2 structure declares the method inside its body and defines it in a separate implementation file. Example code: //Interface header struct Class1:IUnknown, Interface1, Interface2 { DECLARE_AND_DEFINE_COM_QUERY_INTERFACE_BEGIN DEFINE_COM_QUERY_INTERFACE_ADD_ENTRY(Interface1_IID, Interface1) DEFINE_COM_QUERY_INTERFACE_ADD_ENTRY(Interface2_IID, Interface2) DEFINE_COM_QUERY_INTERFACE_END }; struct Class2:IUnknown, Interface1, Interface2 { DECLARE_COM_QUERY_INTERFACE }; //Implementation source DEFINE_COM_QUERY_INTERFACE_BEGIN(Class2) DEFINE_COM_QUERY_INTERFACE_ADD_ENTRY(Interface1_IID, Interface1) DEFINE_COM_QUERY_INTERFACE_ADD_ENTRY(Interface2_IID, Interface2) DEFINE_COM_QUERY_INTERFACE_END
#define	DECLARE_COM_QUERY_INTERFACE   virtual HRESULT __stdcall QueryInterface(REFIID refiid, void** ppv);
#define	DECLARE_AND_DEFINE_COM_QUERY_INTERFACE_BEGIN
#define	DEFINE_COM_QUERY_INTERFACE_BEGIN(classname)
#define	DEFINE_COM_QUERY_INTERFACE_ADD_ENTRY(iid_value, iface_type)   else if (refiid == iid_value) *ppv = static_cast<std::remove_pointer_t<iface_type>*> (this);
#define	DEFINE_COM_QUERY_INTERFACE_END   else {*ppv = NULL; return E_NOINTERFACE;} return S_OK;}

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