[XMPP] C drones do not directly terminate Jabber streams upon self-exit

[Galen Charlton]

C service drones do not explicitly terminate their XMPP sessions by sending a "</stream:stream>" message prior to exiting voluntarily (as opposed to being terminated by the listener). Instead, the socket just gets closed when the process ends. (Perl services do cleanly end their XMPP session upon self-exit.)

This doesn't appear to be the end of the world, but it does cause "Connection failed: connection closed" noise in the Ejabberd logs that can mask true connection failures.

Looks like osrf_prefork_child_exit() is where the client connection cleanup would be added.

[Galen Charlton (gmc)]

Patch is available in the branch user/gmcharlt/lp2047701_graceful_xmpp_disconnect_c / https://git.evergreen-ils.org/?p=working/OpenSRF.git;a=shortlog;h=refs/heads/user/gmcharlt/lp2047701_graceful_xmpp_disconnect_c