mixed threading creates an exception

[Tristan Richardson]

>>>>>>>>> Daniel Popowich <popowich@sovereign-hill.com> wrote:
> 
> I'm using omniORB to serve up some legacy code that uses a threading
> package from ObjectSpace.  ObjectSpace's thread class os_thread, like
> omni_thread, encapsulates underlying native threading in a
> cross-platform, simple-to-use class.
> 
> I have run into a problem on NT4.0 when calling impl_shutdown() on a
> CORBA::BOA_ptr when the method is called from a thread created by
> os_thread.  In other words, if boa->impl_shutdown is NOT called from
> the main thread, or a thread generated by omnithread I get an
> exception thrown in omni_thread::self() (src/lib/omnithread/nt.cc).
> The trace is as follows:
> 
>     CORBA::BOA::impl_shutdown()
>     StrandScavanger::killInScavanger()
>     omni_thread::join()
>     omni_thread::self()
> 
> I do NOT have this problem on Solaris.  Exact same code, call
> boa->impl_shutdown() from an ObjectSpace thread and I have no
> problems.  This problem only exists on NT.
> 
> What seems particularly frustrating is that both ObjectSpace and
> omnithread appear to be using the exact same underlying win32 native
> threading.  
> 
> Has anyone else seen similar behaviour?  Is this a bug?  Any
> suggestions (except suggesting rewriting my legacy code using
> omnithread) on how to resolve this will be appreciated.
> 

The call to omni_thread::self() from inside omni_thread::join() is simply
a sanity check.  If you remove it, you should find everything else
still works, so I'd give that a try and see if it solves your problem.

However, there are other parts of omnithread that require an omni_thread
object for the calling thread (e.g. condition variable waits on NT).  I
couldn't guarantee that omniORB doesn't use some of these features, so you
may come across other problems in calling omniORB code from a 
non-omnithread.


Tristan

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