    # File lib/phusion_passenger/debug_logging.rb, line 45
            def self.log_file=(filename)
                    if filename && filename.empty?
                            @@log_filename = nil
                    else
                            @@log_filename = filename
                    end
                    @@log_device.close if @@log_device && !@@log_device.closed?
                    @@log_device = nil
            end