Open Stack

Hi, I'd like you to take a look at this patch for potential
DocImpact.
https://review.openstack.org/20486

Log:
commit 00dbad0825f2653d2a1c3020f7278ed5ffdc2fe4
Author: Florian Hines <syn at ronin.io>
Date:   Fri Jan 25 08:00:33 2013 -0800

    Add optional locking to swift-ring-builder
    
    If invoked as 'swift-ring-builder-safe' the directory containing the builder
    file provided will be locked (via lock_parent_directory()). This provides a
    small safe guard against multiple instances of the swift-ring-builder (or
    other utilities that observe this lock) from attempting to write to or read
    the builder/ring files while operations are in progress.
    
    This is particularly useful in environments where ring management has been
    automated (via Chef or custom solutions) but the operator still occasionally
    needs to manually interact with the ring.
    
    DocImpact
    
    Change-Id: Ia362744a8151a91bfb586d01da582906726852e6