Bug rh#1017884 describes a crash, where dbus_init() failed, which causes
a g_warning(). While writing the warning, a SIGTERM hit, and the
signal_handler() tries to call again g_message().
The logging functions of glib are not reentrant and call abort() when
invoked recursivly. The solution, is to use g_unix_signal_add, which
will dispatch the handler on the mainloop asynchronously.
This bug is not that serious, because the dispatcher was about to
terminate anyway. However, it gets registered as a crash by the system
(ABRT).
https://bugzilla.redhat.com/show_bug.cgi?id=1017884
Signed-off-by: Thomas Haller <thaller@redhat.com>