class RuboCop::Server::Cache

def acquire_lock
  lock_file = File.open(lock_path, File::CREAT)
  # flock returns 0 if successful, and false if not.
  flock_result = lock_file.flock(File::LOCK_EX | File::LOCK_NB)
  yield flock_result != false
ensure
  lock_file.flock(File::LOCK_UN)
  lock_file.close
end