[PATCH] sunrpc: Do not unregister services if not registered [BZ #5010]

[Florian Weimer]

* Florian Weimer:

> The change in commit 718946816cf60374f9d8f674d3ed649fdb33205a
> has no effect because of two bugs which cancel each other out:
> The svc_is_mapped condition is inverted, and svc_is_mapped
> always returns false because the check is performed after
> the service has already been unregistered.  As a result,
> pmap_unset is called unconditionally, as before.
>
> 2017-02-08  Florian Weimer  <fweimer@redhat.com>
>
> 	[BZ #5010]
> 	* sunrpc/svc.c (svc_is_mapped): Remove.
> 	(svc_unregister): Obtain mapped status while the service is still
> 	registered.
> 	* sunrpc/Makefile [have-thread-library] (tests): Add
> 	tst-svc_register.
> 	(tst-svc_register): Link against libc.so explicitly and the thread
> 	library.
> 	* sunrpc/tst-svc_register.c: New file.

A completely different approach would remove this functionality
altogether (and realign the code with libtirpc).

Any preferences?  Thanks.