This reverts commit 5021ef82fd.
That commit set default location for lock files to a world-writable
directory (like /tmp) which violates security precaution stated right in
the help string of lock_path config variable: lock_path should be
writable by the user of the process using it only.
There is some history behind this:
- when we decided to not do tempfile.mkdtemp if lock_path were not set
(because it was broken), it broke upgrades for all components
(starting with Cinder;
- it was suggested to provide the same default value:
https://review.openstack.org/60274
but it was not accepted because it weakens security;
- there was a thread about this in ML, please read it for more history:
http://lists.openstack.org/pipermail/openstack-dev/2013-December/021055.html
it ended up with understanding that only a project using the library
can provide sane default value for lock_path, not the library itself.
Change-Id: I801004ad3c83862849696f00c6e7ca9877fd496b
499d5aa36d