[racket] Com Service with ffi

At Thu, 11 Oct 2012 11:28:19 +0200, heraklea at gmx.de wrote:
> So far so good:
> (define _ULONG _ulong)
> (define _CATID _GUID)
> (define _REFCATID _GUID-pointer)
> (define-cstruct _CATEGORYINFO ( [catid _CATID]
>                                 [lcid _LCID]
>                                 [szDescription (_array _short 128)])) 
> (define IID_ICustomList
>             (string->iid "{3039E12D-6CEF-4F91-AE9B-E609481C8824}"))
> (define CustomList (com-create-instance "MySrv.CustomList.1"))
> 
> (define-com-interface (_ICustomList _IUnknown)
>     ([Next/ci (_mfun (_ULONG = 1)
>                  (catinfo : (_ptr o _CATEGORYINFO))
>                 (got : (_ptr o _ULONG))
>                 -> (r : _HRESULT)
>                 -> (cond
>                 [(zero? r) catinfo]
>                 [(= r 1) #f]
>                 [else (windows-error "Next/ci
>     failed" r)]))]
>         [Skip _fpointer]
>         [Reset _fpointer]
>         [Clone _fpointer])) 
> 
> (define icat (QueryInterface (com-object-get-iunknown CustomList)
>                                IID_ICustomList
>                                _ICustomList-pointer))
> 
> But I dont understand your third suggestion. lets assume my Interface have a 
> method CallMe(...). How do I implement it and call it after.
>
> I assume you mean this part:
> (define-com-interface (_ICatInformation _IUnknown)
>   ([EnumCategories (_hmfun _LCID
>                            (p : (_ptr o _IEnumCATEGORYINFO-pointer))
>                            -> EnumCategories p)]
> 
> 
> with EnumCategories as method??

Yes, `EnumCategories' is an example of a method. You will need to have
a `CallMe' method declared in some `define-com-interface' declaration
for `_ISomething', and then you invoke the `CallMe' method by applying
`CallMe' to an `_ISomething-pointer' value followed by arguments to the
method.


(Sorry for the delay -- hope this is still soon enough to be useful.)