Make register and unregister functions return void because
we can check the state of callback object beforehand via
virConnectCloseCallbackDataGetCallback. This can be done
without race conditions if we use higher level locks for registering
and unregistering. The fact they return void simplifies
task of consistent registering/unregistering.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
There are also a couple that were very uninformatively just logging
the value of the pointer rather than the string itself:
* the "name" arg to virNodeDeviceLookupByName()
* wwnn and wwpn args to virNodeDeviceLookupSCSIHostByWWN()
All char*'s that make sense should now have their contents logged
rather than the pointer, and all %s args should now be inside
NULLSTR().
