47 lines
1.2 KiB
Ruby
47 lines
1.2 KiB
Ruby
# -*- coding: binary -*-
|
|
require 'bit-struct/char-field'
|
|
|
|
class BitStruct
|
|
# Class for char fields that can be accessed with values like
|
|
# "xxx.xxx.xxx.xxx", where each xxx is up to 3 decimal digits representing a
|
|
# single octet. The original string-based accessors are still available with
|
|
# the <tt>_chars</tt> suffix.
|
|
#
|
|
# Declared with BitStruct.octets.
|
|
class OctetField < BitStruct::CharField
|
|
# Used in describe.
|
|
def self.class_name
|
|
@class_name ||= "octets"
|
|
end
|
|
|
|
SEPARATOR = "."
|
|
FORMAT = "%d"
|
|
BASE = 10
|
|
|
|
def add_accessors_to(cl, attr = name) # :nodoc:
|
|
attr_chars = "#{attr}_chars"
|
|
super(cl, attr_chars)
|
|
sep = self.class::SEPARATOR
|
|
base = self.class::BASE
|
|
fmt = self.class::FORMAT
|
|
|
|
cl.class_eval do
|
|
define_method attr do ||
|
|
ary = []
|
|
send(attr_chars).each_byte do |c|
|
|
ary << fmt % c
|
|
end
|
|
ary.join(sep)
|
|
end
|
|
|
|
old_writer = "#{attr_chars}="
|
|
|
|
define_method "#{attr}=" do |val|
|
|
data = val.split(sep).map{|s|s.to_i(base)}.pack("c*")
|
|
send(old_writer, data)
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|