[omniORB] Possible bug in omniORB 2.7.1

[Sai-Lai Lo]

Poilpret,

Your example seems to me is a legitimate use of the mapping and has not
been covered by omniORB2.

The following is a patch to omni2.7.1 (I believe it should also apply with
no problem to omni2.8.0:

Please note that there should be a proper check in the _d() set function to
see if the argument is valid. This is only partially implemented in the
code below. What it should also check is that the value is none of those of
the labelled union branches. For your purpose I hope it is sufficent:

diff -r -c omni2.7.1/src/tool/omniidl2/omniORB2_be/o2be_union.cc omni2.7.1-new/s
rc/tool/omniidl2/omniORB2_be/o2be_union.cc
*** omni2.7.1/src/tool/omniidl2/omniORB2_be/o2be_union.cc       Mon Apr 17 11:18
:46 2000
--- omni2.7.1-new/src/tool/omniidl2/omniORB2_be/o2be_union.cc   Mon Apr 17 11:18
:20 2000
***************
*** 547,553 ****
            << " _d () const { return pd__d;}\n";
    IND(s); s << "void _d("
            << o2be_name::narrow_and_produce_unambiguous_name(disc_type(),this)
!           << " _value) {}\n\n";
  
    if (nodefault() && !no_missing_disc_value())
      {
--- 547,553 ----
            << " _d () const { return pd__d;}\n";
    IND(s); s << "void _d("
            << o2be_name::narrow_and_produce_unambiguous_name(disc_type(),this)
!           << " _value) { pd__d = (pd__default ? _value : pd__d); }\n\n";
  
    if (nodefault() && !no_missing_disc_value())
      {


Sai-Lai




>>>>> Poilpret Jean Francois writes:

> But there are other cases, where omniidl actually compiles IDL snippet (see
> after), and where the _d() member function SHOULD work:

> enum XXX {one, two, three};

> union YYY switch(XXX) {
>     case three:
>     int        myInt;
> };

> Here, omniidl does not complain, but in this case, I may want to do something
> like this in my C++ code (actually, I DO NEED to do something like this ;-)):

> YYY    yyy;
> yyy._default();
> yyy._d(two);

> If, after this, I try to read the discriminator value:

> std::cout << yyy._d() << std::endl;

> the walue is "one", not "two"; this is because the "_default()" method
> initialized it to be the first enumerated value (of enum XXX) which does not
> appear in any case label.

> But there are many cases where one would like to use the discriminator value
> to hold meaningful information (this is my case), in particular for the
> implicit default case, for which there is no other available information than
> the discriminator value itself.

> So what can I do here (please don't tell me: "use omniORB 3.0", I'm not ready
> yet to upgrade (I think I will in one or two months, but for now, I really
> have no time to do so))?

> Is it possible to path the omniidl compiler to add the right code (only one
> line in fact, regarding my sole problem, since I still did not take care about
> any side-effect problems...) ?


-- 
Sai-Lai Lo                                   S.Lo@uk.research.att.com
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