class Lumberjack::Device::SizeRollingLogFile

production.log.1, then production.log.2, etc.
For example, if the log file is named production.log, the first time it is rolled it will be renamed
size threshold. When a file is rolled, it will have an number extension appended to the file name.
This is a log device that appends entries to a file and rolls the file when it reaches a specified

def archive_file_suffix 

def archive_file_suffix
  next_archive_number.to_s
end

def initialize(path, options = {})

the :max_size option. The unit can also be specified: "32K", "100M", "2G" are all valid.
Create an new log device to the specified file. The maximum size of the log file is specified with 
def initialize(path, options = {})
  @manual = options[:manual]
  @max_size = options[:max_size]
  if @max_size.is_a?(String)
    if @max_size =~ /^(\d+(\.\d+)?)([KMG])?$/i
      @max_size = $~[1].to_f
      units = $~[3].to_s.upcase
      case units
      when "K"
        @max_size *= 1024
      when "M"
        @max_size *= 1024**2
      when "G"
        @max_size *= 1024**3
      end
      @max_size = @max_size.round
    else
      raise ArgumentError.new("illegal value for :max_size (#{@max_size})")
    end
  end
  super
end

def next_archive_number # :nodoc:

:nodoc:
Calculate the next archive file name extension. 
def next_archive_number # :nodoc:
  max = 0
  Dir.glob("#{path}.*").each do |filename|
    if /\.\d+\z/ =~ filename
      suffix = filename.split(".").last.to_i
      max = suffix if suffix > max
    end
  end
  max + 1
end

def roll_file? 

def roll_file?
  @manual || stream.stat.size > @max_size
rescue SystemCallError
  false
end