From: Evan Light <sleight42@...>
Date: 2007-05-08T00:15:05+09:00
Subject: Re: Why is my method not found? (NoMethodError)

Your problem is that there is way too much nesting within your
methods.  You lost track of which "end" maps to which "do" and "begin"
in numerous places.  As a general rule, if you're nesting more than
two levels deep within a method, you just made your method a lot more
difficult to maintain.  The below version fixes your nesting issues
(but does not correct them for maintainability).

require 'socket'
require 'timeout'

  class Scanner

     def initialize
        @hosts,@ports = Array($*)
     end

     def portarrange
        case @ports
          when /^.+[..]/
             @ports = @ports.split("..")
             @ports = @ports[0].to_i..@ports[1].to_i
          when /^.+[,]/
             @ports = @ports.split(",")
          else
             @ports = Array(@ports)
          end
     end

     def hostarrange
        case @hosts
          when /^.+[,]/
             @hosts = @hosts.split(",")
          else
             @hosts = Array(@hosts)
          end
     end

    def output(state,port)
       printed = false
       portsfile = File.new("ports", "r")
       scanpat = "^.+ #{port}/tcp"
       begin
         portsfile.each_line do |line|
           if line =~ Regexp.new(scanpat)
             puts "#{state}    : #{line}"
             printed = true
           end
           puts "#{state}    : #{port}" if printed == false
         end
       ensure
       portsfile.close
       end
    end

    def scanning(hosts,ports)
      hosts.each do |host|
        begin
          puts "scanning #{host}:"
          ports.each do |port|
            begin
              Timeout::timeout(10){TCPSocket.new(host, port)}
            rescue Timeout::Error
              output("filtered",port)
            rescue
              output("closed",port)
            else
              output("open",port)
            end
          end
        end
      end
    end
end

#####################  code  start  #####################

puts "no arguments past,correct usage:\nruby #{$0} [hosts] [ports]\n"
if
!ARGV[1]

my_scanner = Scanner.new

hosts = my_scanner.hostarrange
ports = my_scanner.portarrange
=begin
puts "debugging: "
puts hosts
puts ports
# everything alright until here
=end
my_scanner.scanning(hosts,ports)

#####################      eof      #####################