lib/netchk/icmp.rb in netchk-0.0.1.beta vs lib/netchk/icmp.rb in netchk-0.0.1

@@ -1,15 +1,17 @@
+# rubocop:disable  Style/FrozenStringLiteralComment:
 require 'net/ping/ping'
 
 if File::ALT_SEPARATOR
   require 'win32/security'
 end
 
 # The Net module serves as a namespace only.
 module Netchk
-
-  # The Net::Ping::ICMP class encapsulates an icmp ping.
+  # Modified version of Net::Ping::ICMP that does
+  # not check for root privileges and uses a DGRAM
+  # socket instead of a raw socket.
   class ICMP < ::Net::Ping
     ICMP_ECHOREPLY = 0 # Echo reply
     ICMP_ECHO      = 8 # Echo request
     ICMP_SUBCODE   = 0
 
@@ -22,27 +24,19 @@
     # default size is 56.
     #
     attr_reader :data_size
 
     # Creates and returns a new Ping::ICMP object.  This is similar to its
-    # superclass constructor, but must be created with root privileges (on
-    # UNIX systems), and the port value is ignored.
-    #
-    def initialize(host=nil, port=nil, timeout=5)
-      if File::ALT_SEPARATOR
-        unless Win32::Security.elevated_security?
-          raise 'requires elevated security'
-        end
-      end
-
+    # superclass constructor, and the port value is ignored.
+    def initialize(host = nil, port = nil, timeout = 5)
       @seq = 0
       @bind_port = 0
       @bind_host = nil
       @data_size = 56
       @data = ''
 
-      0.upto(@data_size){ |n| @data << (n % 256).chr }
+      0.upto(@data_size) { |n| @data << (n % 256).chr }
 
       @ping_id = (Thread.current.object_id ^ Process.pid) & 0xffff
 
       super(host, port, timeout)
       @port = nil # This value is not used in ICMP pings.
@@ -51,11 +45,11 @@
     # Sets the number of bytes sent in the ping method.
     #
     def data_size=(size)
       @data_size = size
       @data = ''
-      0.upto(size){ |n| @data << (n % 256).chr }
+      0.upto(size) { |n| @data << (n % 256).chr }
     end
 
     # Associates the local end of the socket connection with the given
     # +host+ and +port+. The default port is 0.
     #
@@ -103,11 +97,11 @@
       start_time = Time.now
 
       socket.send(msg, 0, saddr) # Send the message
 
       begin
-        Timeout.timeout(@timeout){
+        Timeout.timeout(@timeout) {
           while true
             io_array = select([socket], nil, nil, timeout)
 
             if io_array.nil? || io_array[0].empty?
               raise Timeout::Error if io_array.nil?
@@ -147,26 +141,26 @@
       @duration = Time.now - start_time if bool
     end
 
     private
 
-    # Perform a checksum on the message.  This is the sum of all the short
-    # words and it folds the high order bits into the low order bits.
-    #
-    def checksum(msg)
-      length    = msg.length
-      num_short = length / 2
-      check     = 0
+      # Perform a checksum on the message.  This is the sum of all the short
+      # words and it folds the high order bits into the low order bits.
+      #
+      def checksum(msg)
+        length    = msg.length
+        num_short = length / 2
+        check     = 0
 
-      msg.unpack("n#{num_short}").each do |short|
-        check += short
-      end
+        msg.unpack("n#{num_short}").each do |short|
+          check += short
+        end
 
-      if length % 2 > 0
-        check += msg[length-1, 1].unpack('C').first << 8
-      end
+        if length % 2 > 0
+          check += msg[length - 1, 1].unpack('C').first << 8
+        end
 
-      check = (check >> 16) + (check & 0xffff)
-      return (~((check >> 16) + check) & 0xffff)
-    end
+        check = (check >> 16) + (check & 0xffff)
+        return (~((check >> 16) + check) & 0xffff)
+      end
   end
 end