Callback mit externer C-dll

[NicoDE]

Apropos Service, hier ist eine Version die mit 'pascal', 'stdcall' und 'safecall' (auch unter WinXP SP2) funktioniert:
(falls es mal jemand brauchen sollte)

Delphi-Quellcode:

////////////////////////////////////////////////////////////////////////////////
//
//  MakeStdcallCallback (thunk to use stdcall method as static callback)
//  (works too for pascal and safecall, but NOT for cdecl and register!)

function MakeStdcallCallback(const Method: TMethod): Pointer;
{$IFDEF WIN32}
type
  PCallbackCode = ^TCallbackCode;
  TCallbackCode = packed record
    Ops1: array [0..2] of Longword;
    Val1: Pointer;
    Ops2: array [0..1] of Longword;
    Val2: Pointer;
  end;
{$ENDIF}
begin
{$IFDEF WIN32}
  Result := VirtualAlloc(nil, $100, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
  if Assigned(Result) then
    try
      with PCallbackCode(Result)^ do
      begin
        // ; do not change registers!
        // push    eax                         ; stack space (Self)
        // push    eax                         ; backup accumulator 
        // mov     eax, [esp+8]                ; get return address
        // mov     [esp+4], eax                ; save at lower addr
        // mov     eax, [x].TMethod.Data       ; get x.Self pointer
        // mov     [esp+8], eax                ; save it into space
        // pop     eax                         ; get eax from stack
        // nop                                 ; think about it *g*
        // jmp     dword ptr [x].TMethod.Code  ; now jump to method
        // ; no need to cleanup stack
        Ops1[0] := $448B5050;
        Ops1[1] := $44890824;
        Ops1[2] := $058B0424;
        Val1 := Addr(Method.Data);
        Ops2[0] := $08244489;
        Ops2[1] := $25FF9058;
        Val2 := Addr(Method.Code);
      end;
    except
      VirtualFree(Result, 0, MEM_RELEASE);
      Result := nil;
    end;
{$ELSE}
  Result := nil;
{$ENDIF}
end;

procedure FreeCallback(Callback: Pointer);
begin
{$IFDEF WIN32}
  if Assigned(Callback) then
    VirtualFree(Callback, 0, MEM_RELEASE);
{$ENDIF}
end;

Fehlt nur noch 'register', aber dazu bin ich heute zu faul.