#first, #last, #network, and #broadcast properly handle /31 (RFC3021) and /32

2 files changed, 40 insertions, 8 deletions

diff --git a/lib/ipaddress/ipv4.rb b/lib/ipaddress/ipv4.rb
index a798a24..d68dfa9 100644
--- a/lib/ipaddress/ipv4.rb
+++ b/lib/ipaddress/ipv4.rb
@@ -294,9 +294,16 @@ module IPAddress;
     #     #=> "172.16.10.255"
     #
     def broadcast
-      self.class.parse_u32(broadcast_u32, @prefix)
+      case
+      when prefix <= 30
+        self.class.parse_u32(broadcast_u32, @prefix)
+      when prefix == 31
+        self.class.parse_u32(-1, @prefix)
+      when prefix == 32
+        return nil
+      end
     end
-    
+
     #
     # Checks if the IP address is actually a network
     #
@@ -348,7 +355,14 @@ module IPAddress;
     #     #=> "192.168.100.1"
     #
     def first
-      self.class.parse_u32(network_u32+1, @prefix)
+      case
+      when prefix <= 30
+        self.class.parse_u32(network_u32+1, @prefix)
+      when prefix == 31
+        self.class.parse_u32(network_u32, @prefix)
+      when prefix == 32
+        return self
+      end
     end
 
     #
@@ -373,7 +387,14 @@ module IPAddress;
     #     #=> "192.168.100.254"
     #
     def last
-      self.class.parse_u32(broadcast_u32-1, @prefix)
+      case
+      when prefix <= 30
+        self.class.parse_u32(broadcast_u32-1, @prefix)
+      when prefix == 31
+        self.class.parse_u32(broadcast_u32, @prefix)
+      when prefix == 32
+        return self
+      end
     end
 
     #
@@ -461,7 +482,7 @@ module IPAddress;
       return prefix <=> oth.prefix if to_u32 == oth.to_u32  
       to_u32 <=> oth.to_u32
     end
-    
+
     #
     # Returns the number of IP addresses included
     # in the network. It also counts the network
diff --git a/test/ipaddress/ipv4_test.rb b/test/ipaddress/ipv4_test.rb
index 38cac74..6518bf1 100644
--- a/test/ipaddress/ipv4_test.rb
+++ b/test/ipaddress/ipv4_test.rb
@@ -26,7 +26,8 @@ class IPv4Test < Test::Unit::TestCase
       "10.0.0.0/8"       => "255.0.0.0",
       "172.16.0.0/16"    => "255.255.0.0",
       "192.168.0.0/24"   => "255.255.255.0",
-      "192.168.100.4/30" => "255.255.255.252"}
+      "192.168.100.4/30" => "255.255.255.252",
+      "192.168.12.4/32"  => "255.255.255.255"}
 
     @decimal_values ={      
       "0.0.0.0/0"        => 0,
@@ -42,13 +43,17 @@ class IPv4Test < Test::Unit::TestCase
       "10.0.0.0/8"       => "10.255.255.255/8",
       "172.16.0.0/16"    => "172.16.255.255/16",
       "192.168.0.0/24"   => "192.168.0.255/24",
-      "192.168.100.4/30" => "192.168.100.7/30"}
+      "192.168.100.4/30" => "192.168.100.7/30",
+      "192.168.12.3/31"  => "255.255.255.255/31",
+      "10.0.0.1/32"      => nil}
     
     @networks = {
       "10.5.4.3/8"       => "10.0.0.0/8",
       "172.16.5.4/16"    => "172.16.0.0/16",
       "192.168.4.3/24"   => "192.168.4.0/24",
-      "192.168.100.5/30" => "192.168.100.4/30"}
+      "192.168.100.5/30" => "192.168.100.4/30",
+      "192.168.1.3/31"   => "192.168.1.2/31",
+      "192.168.2.5/32"   => "192.168.2.5/32"}
 
     @class_a = @klass.new("10.0.0.1/8")
     @class_b = @klass.new("172.16.0.1/16")
@@ -181,6 +186,9 @@ class IPv4Test < Test::Unit::TestCase
     ip = @klass.new("192.168.100.50/32")
     assert_instance_of @klass, ip.first
     assert_equal "192.168.100.50", ip.first.to_s
+    ip = @klass.new("192.168.100.50/31")
+    assert_instance_of @klass, ip.first
+    assert_equal "192.168.100.50", ip.first.to_s
   end
 
   def test_method_last
@@ -193,6 +201,9 @@ class IPv4Test < Test::Unit::TestCase
     ip = @klass.new("192.168.100.50/32")
     assert_instance_of @klass, ip.last
     assert_equal  "192.168.100.50", ip.last.to_s
+    ip = @klass.new("192.168.100.50/31")
+    assert_instance_of @klass, ip.last
+    assert_equal  "192.168.100.51", ip.last.to_s
   end
   
   def test_method_each_host