PL/SQL and DLLs

From: Roga Danar <nospam_at_nospam.com>
Date: Thu, 29 Oct 1998 10:50:58 -0600
Message-ID: <36389CF2.63E65FB2_at_nospam.com>

Hello,

  I am having trouble interfacing with a DLL on WinNT and PL/SQL 2.3.4.0.0

  If anyone can help with this in would be great. The error I get is an unknown exception returned from the actual interface call (FF_UP). I cannot debug very well.

  The handles to the function and parameter and return types all return with no error.

  I have also tried to change the PLS_INTEGER type to NUMBER and INTEGER and I still got the same result.

  Thanks in advance,

  Michael G. Smith

  The code follows

---

PROCEDURE dll_test IS

  rtn_val PLS_INTEGER;

  DLL_Handle ora_ffi.libhandletype;
  up_handle ora_ffi.funchandletype;

  function ff_up (fhandle ora_ffi.funchandletype, i integer)

           return PLS_INTEGER;
  pragma interface(C, ff_up, up);

  function up_one (I pls_integer)

     return pls_integer is
  begin
    Text_Io.Put_Line ('Calling FF_UP routine');     return (ff_up (up_handle, I));
    Text_IO.Put_LIne ('** Done calling FF_UP ** ');   EXCEPTION

     WHEN ORA_FFI.FFI_ERROR THEN
        TEXT_IO.PUT_LINE ('*** FFI_Error occured in: UP_ONE function


***');

        raise;
     WHEN OTHERS THEN
        TEXT_IO.PUT_LINE ('*** Something really BAD happened: UP_ONE

***');

  END; BEGIN   text_io.put_line('Testing DLL invocation');

  dll_handle :=
    Ora_Ffi.Load_Library

      ('C:\Work\C_Work\dllprog\Debug\',
        'dllprog.dll');

  text_io.put_line('Got LIB handle');

  BEGIN
    up_handle := ora_ffi.register_function   (dll_handle, 'up_one', ora_ffi.c_std);   EXCEPTION

     WHEN ORA_FFI.FFI_ERROR THEN
        TEXT_IO.PUT_LINE ('*** FFI_ERROR: Could NOT register function


***');

        raise;
     WHEN OTHERS THEN
        TEXT_IO.PUT_LINE ('*** Unknown Exception: REGISTER FUNCTION


***');

        RAISE;

  END;   text_io.put_line('Got FUNCTION handle');

  BEGIN
     ora_ffi.register_parameter(up_handle,ora_ffi.c_int);   EXCEPTION

     WHEN ORA_FFI.FFI_ERROR THEN
        TEXT_IO.PUT_LINE ('*** FFI_Error occured in: REGISTER PARAMETER
function ***');
        raise;
     WHEN OTHERS THEN
        TEXT_IO.PUT_LINE ('*** Unknown Exception: REGISTER PARAMETER


***');

        RAISE;

  END;   text_io.put_line ('Registered PARAMETER');

  BEGIN
     ora_ffi.register_return(up_handle,ora_ffi.c_int);   EXCEPTION

     WHEN ORA_FFI.FFI_ERROR THEN
        TEXT_IO.PUT_LINE ('*** FFI_Error occured in: REGISTER RETURN
function ***');
        raise;
     WHEN OTHERS THEN
        TEXT_IO.PUT_LINE ('*** Unknown Exception: REGISTER RETURN ***');

        RAISE;

  END;   TEXT_IO.PUT_LINE ('Registered Return');

  Text_IO.Put_LIne ('**************************');

  text_io.put_line ('Making the call to ONE UP');   rtn_val := up_one(10);

  text_io.put_line('<=====>');
  text_io.put (rtn_val);
  text_io.new_line;
  text_io.put_line('<=====>');

  text_io.put_line ('*** === > Done!! < === ***');

EXCEPTION
   WHEN ORA_FFI.FFI_ERROR THEN
     TEXT_IO.PUT_LINE ('*** Could NOT register function ***');    WHEN OTHERS THEN
     TEXT_IO.PUT_LINE ('*** Something really BAD happened ***'); END DLL_TEST; Received on Thu Oct 29 1998 - 17:50:58 CET