kenn/redis-mutex — pull request #6 by nviennot (2013-03-07 05:02:46+00:00)
Title: Fixed race in the lock method

if setnx failed and the following get returns nil, it means that the
lock just got unlocked. It's a very unlikely race, but it happens.
This patch change this behavior to redo a setnx if the following get
is nil instead of going through the getset.