JIS (IRCnet) <-> UTF-8 (IRC client) proxy

nkf-proxy.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

require 'nkf'
require 'socket'

Socket.tcp_server_loop(6668) do |socket, client_addr|
  begin
    begin
      ircnet_socket = Socket.tcp('irc.ircnet.ne.jp', 6667)
      loop do
        rs, = IO.select([socket, ircnet_socket])
        break if rs.empty?
        if rs.include?(ircnet_socket)
          jis_line = ircnet_socket.gets
          socket.puts NKF.nkf('-Jwxm0 --fb-xml', jis_line)
        end
        if rs.include?(socket)
          utf8_line = socket.gets
          ircnet_socket.puts NKF.nkf('-Wjxm0 --fb-xml', utf8_line)
        end
      end
    rescue
      p $!
    ensure
      ircnet_socket.close if ircnet_socket && !ircnet_socket.closed?
    end
  ensure
    socket.close if !socket.closed?
  end
end

new generic version is https://github.com/znz/ansible-playbook-raspi201804/blob/master/provision/roles/matterbridge/files/nkf-proxy.rb