Issue 636:  Inconsistency in CORBA 2.0 C mapping (c_mapping-rtf)
Source:  (, )
Nature:  Uncategorized
Severity: 
Summary: Summary: I currently implement a subset of CORBA 2.0. Not CORBA-compliant in terms of C-mapping for arguments to pseudo-objects and real objects. Give clear statement on argument order for real objects

Resolution: 
Revised Text: 
Actions taken:
July 29, 1997: received issue
Discussion: 

End of Annotations:=====
Return-Path: <pangburn@fnal.gov>
Sender: pangburn@fnal.gov
Date: Tue, 29 Jul 1997 12:12:20 -0500
From: Jim Pangburn <pangburn@fnal.gov>
Organization: Fermi National Accelerator Lab
To: issues@omg.org
Subject: Inconsistency in CORBA 2.0 C mapping

I have already implemented a freeware CORBA ORB in C, with wrappers
for C++ and Java.  I currently implement a subset of CORBA 2.0,
and people seem happy with it.  However, I worry that even this
subset is not CORBA-compliant in terms of the C mapping for
arguments to pseudo-objects and real objects.  There is no way for 
me to tell from the document, because I believe it is not consistent.
For example, in 14.15 ("Implicit Arguments to Operations"), it says:

	From the point of view of the C programmer, all operations 
	... have addition *leading* parameters *preceding* the
	operation-specific parameters:

It then enumerates the CORBA_Object, (CORBA_Environment *), and
CORBA_Context arguments.  From the statement above, these should
all come BEFORE any operation-specific arguments.  However, in the
description for (CORBA_Environment *), it says:

	The last parameter to each operation is a
	(CORBA_Environment *) output parameter ...

and for CORBA_Context:

	If an operation ... has a context specification, then
	a CORBA_Context input parameter *precedes* the
	(CORBA_Environment *) parameter and *follows* any 
	operation-specific arguments.

So does the (CORBA_Environment *) go last (that is, following
any operation-specific arguments) or not?  I have assumed it does,
because it was the last statement I read.

The remainder of the chapter contains several examples of real
and pseudo-objects, some of which go one way (i.e. foo_bar), 
and some of which go the other (i.e. example4_op5).

Could you please give me a clear statement on argument order for
real objects?  And it would be really nice to just have a concrete
declaration of the entire C mapping for pseudo-objects in the
form of full ANSI prototypes...

Thanks very much,
Jim Pangburn

-- 
------------------------------------------------------------------------
Jim Pangburn		    |  "Any opinions expressed herein are in
no
Fermi Nat'l Accelerator Lab |  way intended to represent those of the
P.O. Box 500 / MS 318	    |  United States government, or any of its
Batavia, IL  60510 (USA)    |  agencies, affiliates, or contractors."
(630) 840-2207  FAX: -6315  | NO SOLICITORS!
------------------------------------------------------------------------