coreos/rocket — pull request #309 by vcaputo (2014-12-29 23:33:13+00:00)
Title: pkg/lock: refactor DirLock to facilitate discrete opens

This also restores atomic lock conversions

* Discard DirLock interface
* Convert private lock struct into public DirLock
* Convert private newLock function to public NewLock
* Introduce receiver-based analogs of all acquisition functions
* Convert existing open+acquire functions to use the public receiver-based
acquistion functions.