X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FIPv4Address.hs;h=dac7ddaf0596e9fba46b077d4321e88149d23b88;hb=d32fe2f0a6c83ba3046a405eda40f83c794c000d;hp=6d1e56ec38becf939b0ceede6c0262fb0a2beee6;hpb=4b16a47bd77a82d63072497514476faeba6b8e83;p=hath.git

diff --git a/src/IPv4Address.hs b/src/IPv4Address.hs
index 6d1e56e..dac7dda 100644
--- a/src/IPv4Address.hs
+++ b/src/IPv4Address.hs
@@ -1,140 +1,186 @@
 module IPv4Address
-( ipv4address_from_octets,
-  ipv4address_tests,
-  IPv4Address(None),
+( ipv4address_tests,
+  IPv4Address(..),
   max_address,
   min_address,
   most_sig_bit_different,
-  octet1,
-  octet2,
-  octet3,
-  octet4
 ) where
 
-import Test.HUnit
-import Test.QuickCheck
+import Data.Maybe (fromJust)
+import Test.HUnit (assertEqual)
+import Test.Framework (Test, testGroup)
+import Test.Framework.Providers.HUnit (testCase)
+import Test.QuickCheck (Arbitrary(..), Gen)
 
 import Maskable
 import Maskbits
 import Octet
 
-data IPv4Address = None | IPv4Address { octet1 :: Octet,
-                                        octet2 :: Octet,
-                                        octet3 :: Octet,
-                                        octet4 :: Octet }
-                 deriving (Eq)
+data IPv4Address =
+  IPv4Address { octet1 :: Octet,
+                octet2 :: Octet,
+                octet3 :: Octet,
+                octet4 :: Octet }
+    deriving (Eq)
 
 
 instance Show IPv4Address where
-    show IPv4Address.None = "None"
-    show addr = concat [(show oct1) ++ ".",
-                        (show oct2) ++ ".",
-                        (show oct3) ++ ".",
-                        (show oct4)]
-        where
-          oct1 = (octet1 addr)
-          oct2 = (octet2 addr)
-          oct3 = (octet3 addr)
-          oct4 = (octet4 addr)
+  show addr = concat [(show oct1) ++ ".",
+                      (show oct2) ++ ".",
+                      (show oct3) ++ ".",
+                      (show oct4)]
+      where
+        oct1 = (octet1 addr)
+        oct2 = (octet2 addr)
+        oct3 = (octet3 addr)
+        oct4 = (octet4 addr)
 
 
 instance Arbitrary IPv4Address where
-    arbitrary = do
-      oct1 <- arbitrary :: Gen Octet
-      oct2 <- arbitrary :: Gen Octet
-      oct3 <- arbitrary :: Gen Octet
-      oct4 <- arbitrary :: Gen Octet
-      return (IPv4Address oct1 oct2 oct3 oct4)
-
-    coarbitrary _ = variant 0
+  arbitrary = do
+    oct1 <- arbitrary :: Gen Octet
+    oct2 <- arbitrary :: Gen Octet
+    oct3 <- arbitrary :: Gen Octet
+    oct4 <- arbitrary :: Gen Octet
+    return (IPv4Address oct1 oct2 oct3 oct4)
 
 
 
 instance Maskable IPv4Address where
-    apply_mask _ Maskbits.None _ = IPv4Address.None
-    apply_mask addr mask bit
-        | mask == ThirtyTwo = addr
-        | mask == ThirtyOne = addr { octet4 = (apply_mask oct4 Seven bit) }
-        | mask == Thirty = addr { octet4 = (apply_mask oct4 Six bit) }
-        | mask == TwentyNine = addr { octet4 = (apply_mask oct4 Five bit) }
-        | mask == TwentyEight = addr { octet4 = (apply_mask oct4 Four bit) }
-        | mask == TwentySeven = addr { octet4 = (apply_mask oct4 Three bit) }
-        | mask == TwentySix = addr { octet4 = (apply_mask oct4 Two bit) }
-        | mask == TwentyFive = addr { octet4 = (apply_mask oct4 One bit) }
-        | mask == TwentyFour = addr { octet4 = min_octet }
-        | mask == TwentyThree = addr { octet3 = (apply_mask oct3 Seven bit),
-                                       octet4 = min_octet }
-        | mask == TwentyTwo = addr { octet3 = (apply_mask oct3 Six bit),
-                                     octet4 = min_octet }
-        | mask == TwentyOne = addr { octet3 = (apply_mask oct3 Five bit),
-                                     octet4 = min_octet }
-        | mask == Twenty = addr { octet3 = (apply_mask oct3 Four bit),
-                                  octet4 = min_octet }
-        | mask == Nineteen = addr { octet3 = (apply_mask oct3 Three bit),
-                                    octet4 = min_octet }
-        | mask == Eighteen = addr { octet3 = (apply_mask oct3 Two bit),
-                                    octet4 = min_octet }
-        | mask == Seventeen = addr { octet3 = (apply_mask oct3 One bit),
-                                     octet4 = min_octet }
-        | mask == Sixteen = addr { octet3 = min_octet,
-                                   octet4 = min_octet }
-        | mask == Fifteen = min_address { octet1 = oct1,
-                                          octet2 = (apply_mask oct2 Seven bit) }
-        | mask == Fourteen = min_address { octet1 = oct1,
-                                           octet2 = (apply_mask oct2 Six bit) }
-        | mask == Thirteen = min_address { octet1 = oct1,
-                                           octet2 = (apply_mask oct2 Five bit) }
-        | mask == Twelve = min_address { octet1 = oct1,
-                                         octet2 = (apply_mask oct2 Four bit) }
-        | mask == Eleven = min_address { octet1 = oct1,
-                                         octet2 = (apply_mask oct2 Three bit) }
-        | mask == Ten = min_address { octet1 = oct1,
-                                      octet2 = (apply_mask oct2 Two bit) }
-        | mask == Nine = min_address { octet1 = oct1,
-                                       octet2 = (apply_mask oct2 One bit) }
-        | mask == Eight = min_address { octet1 = oct1 }
-        | mask == Seven = min_address { octet1 = (apply_mask oct1 Seven bit) }
-        | mask == Six = min_address { octet1 = (apply_mask oct1 Six bit) }
-        | mask == Five = min_address { octet1 = (apply_mask oct1 Five bit) }
-        | mask == Four = min_address { octet1 = (apply_mask oct1 Four bit) }
-        | mask == Three = min_address { octet1 = (apply_mask oct1 Three bit) }
-        | mask == Two = min_address { octet1 = (apply_mask oct1 Two bit) }
-        | mask == One = min_address { octet1 = (apply_mask oct1 One bit) }
-        | mask == Zero = min_address
-        | otherwise = IPv4Address.None
-        where
-          oct1 = (octet1 addr)
-          oct2 = (octet2 addr)
-          oct3 = (octet3 addr)
-          oct4 = (octet4 addr)
-
-
--- We don't export our constructor so this function is the only
--- way to construct an address from octets. As a result, we can
--- return IPv4Address.None in response to being passed one of more
--- Octet.None octets.
-ipv4address_from_octets :: Octet -> Octet -> Octet -> Octet -> IPv4Address
-ipv4address_from_octets oct1 oct2 oct3 oct4
-    | or [oct1 == Octet.None,
-          oct2 == Octet.None,
-          oct3 == Octet.None,
-          oct4 == Octet.None] = IPv4Address.None
-    | otherwise = IPv4Address oct1 oct2 oct3 oct4
-
-
--- The minimum possible IPv4 address, 0.0.0.0.
+
+  apply_mask addr mask bit =
+   apply_mask' mask
+   where
+     oct1 = octet1 addr
+     oct2 = octet2 addr
+     oct3 = octet3 addr
+     oct4 = octet4 addr
+
+     -- A copy of 'addr' with the fourth octet zeroed (or oned).
+     new_addr1 = addr { octet4 = (apply_mask oct4 Zero bit) }
+
+     -- Likewise for new_addr1's third octet.
+     new_addr2 = new_addr1 { octet3 = (apply_mask oct3 Zero bit) }
+
+     -- And new_addr2's second octet.
+     new_addr3 = new_addr2 { octet2 = (apply_mask oct2 Zero bit) }
+
+     -- This helper function allows us to pattern-match cleanly.
+     apply_mask' :: Maskbits -> IPv4Address
+
+     apply_mask' ThirtyTwo = addr
+
+     apply_mask' ThirtyOne = addr { octet4 = (apply_mask oct4 Seven bit) }
+
+     apply_mask' Thirty =
+       addr { octet4 = (apply_mask oct4 Six bit) }
+
+     apply_mask' TwentyNine =
+       addr { octet4 = (apply_mask oct4 Five bit) }
+
+     apply_mask' TwentyEight =
+       addr { octet4 = (apply_mask oct4 Four bit) }
+
+     apply_mask' TwentySeven =
+       addr { octet4 = (apply_mask oct4 Three bit) }
+
+     apply_mask' TwentySix =
+       addr { octet4 = (apply_mask oct4 Two bit) }
+
+     apply_mask' TwentyFive =
+       addr { octet4 = (apply_mask oct4 One bit) }
+
+     apply_mask' TwentyFour = new_addr1
+
+     apply_mask' TwentyThree =
+       new_addr1 { octet3 = (apply_mask oct3 Seven bit) }
+
+     apply_mask' TwentyTwo =
+       new_addr1 { octet3 = (apply_mask oct3 Six bit) }
+
+     apply_mask' TwentyOne =
+       new_addr1 { octet3 = (apply_mask oct3 Five bit) }
+
+     apply_mask' Twenty =
+       new_addr1 { octet3 = (apply_mask oct3 Four bit) }
+
+     apply_mask' Nineteen =
+       new_addr1 { octet3 = (apply_mask oct3 Three bit) }
+
+     apply_mask' Eighteen =
+       new_addr1 { octet3 = (apply_mask oct3 Two bit) }
+
+     apply_mask' Seventeen =
+       new_addr1 { octet3 = (apply_mask oct3 One bit) }
+
+     apply_mask' Sixteen =
+       new_addr2
+
+     apply_mask' Fifteen =
+       new_addr2 { octet2 = (apply_mask oct2 Seven bit) }
+
+     apply_mask' Fourteen =
+       new_addr2 { octet2 = (apply_mask oct2 Six bit) }
+
+     apply_mask' Thirteen =
+       new_addr2 { octet2 = (apply_mask oct2 Five bit) }
+
+     apply_mask' Twelve =
+       new_addr2 { octet2 = (apply_mask oct2 Four bit) }
+
+     apply_mask' Eleven =
+       new_addr2 { octet2 = (apply_mask oct2 Three bit) }
+
+     apply_mask' Ten =
+       new_addr2 { octet2 = (apply_mask oct2 Two bit) }
+
+     apply_mask' Nine =
+       new_addr2 { octet2 = (apply_mask oct2 One bit) }
+
+     apply_mask' Eight =
+       new_addr3 { octet2 = (apply_mask oct2 Zero bit) }
+
+     apply_mask' Seven =
+       new_addr3 { octet1 = (apply_mask oct1 Seven bit) }
+
+     apply_mask' Six =
+       new_addr3 { octet1 = (apply_mask oct1 Six bit) }
+
+     apply_mask' Five =
+       new_addr3 { octet1 = (apply_mask oct1 Five bit) }
+
+     apply_mask' Four =
+       new_addr3 { octet1 = (apply_mask oct1 Four bit) }
+
+     apply_mask' Three =
+       new_addr3 { octet1 = (apply_mask oct1 Three bit) }
+
+     apply_mask' Two =
+       new_addr3 { octet1 = (apply_mask oct1 Two bit) }
+
+     apply_mask' One =
+       new_addr3 { octet1 = (apply_mask oct1 One bit) }
+
+     apply_mask' Zero =
+       new_addr3 { octet1 = (apply_mask oct1 Zero bit) }
+
+
+
+-- | The minimum possible IPv4 address, 0.0.0.0.
 min_address :: IPv4Address
-min_address = IPv4Address min_octet min_octet min_octet min_octet
+min_address =
+  IPv4Address min_octet min_octet min_octet min_octet
 
 
--- The maximum possible IPv4 address, 255.255.255.255.
+-- | The maximum possible IPv4 address, 255.255.255.255.
 max_address :: IPv4Address
-max_address = IPv4Address max_octet max_octet max_octet max_octet
+max_address =
+  IPv4Address max_octet max_octet max_octet max_octet
 
 
--- Given two addresses, find the number of the most significant bit
--- where they differ. If the addresses are the same, return
--- Maskbits.Zero.
+-- | Given two addresses, find the number of the most significant bit
+--   where they differ. If the addresses are the same, return
+--   Maskbits.Zero.
 most_sig_bit_different :: IPv4Address -> IPv4Address -> Maskbits
 most_sig_bit_different addr1 addr2
   | addr1 == addr2 = Maskbits.Zero
@@ -250,24 +296,41 @@ most_sig_bit_different addr1 addr2
 -- HUnit Tests
 mk_testaddr :: Int -> Int -> Int -> Int -> IPv4Address
 mk_testaddr a b c d =
-    IPv4Address oct1 oct2 oct3 oct4
-    where
-      oct1 = octet_from_int a
-      oct2 = octet_from_int b
-      oct3 = octet_from_int c
-      oct4 = octet_from_int d
+  IPv4Address oct1 oct2 oct3 oct4
+  where
+    oct1 = fromJust $ octet_from_int a
+    oct2 = fromJust $ octet_from_int b
+    oct3 = fromJust $ octet_from_int c
+    oct4 = fromJust $ octet_from_int d
 
 
 test_most_sig_bit_different1 :: Test
 test_most_sig_bit_different1 =
-    TestCase $ assertEqual "10.1.1.0 and 10.1.0.0 differ in bit 24" TwentyFour (most_sig_bit_different (mk_testaddr 10 1 1 0) (mk_testaddr 10 1 0 0))
+  testCase desc $ assertEqual desc
+             TwentyFour
+             bit
+  where
+    desc = "10.1.1.0 and 10.1.0.0 differ in bit 24"
+    addr1 = mk_testaddr 10 1 1 0
+    addr2 = (mk_testaddr 10 1 0 0)
+    bit = most_sig_bit_different addr1 addr2
+
 
 
 test_most_sig_bit_different2 :: Test
 test_most_sig_bit_different2 =
-    TestCase $ assertEqual "10.1.2.0 and 10.1.1.0 differ in bit 23" TwentyThree (most_sig_bit_different (mk_testaddr 10 1 2 0) (mk_testaddr 10 1 1 0))
+  testCase desc $ assertEqual desc
+               TwentyThree
+               bit
+  where
+    desc = "10.1.2.0 and 10.1.1.0 differ in bit 23"
+    addr1 = mk_testaddr 10 1 2 0
+    addr2 = mk_testaddr 10 1 1 0
+    bit = most_sig_bit_different addr1 addr2
 
 
-ipv4address_tests :: [Test]
-ipv4address_tests = [ test_most_sig_bit_different1,
-                      test_most_sig_bit_different2 ]
+ipv4address_tests :: Test
+ipv4address_tests =
+  testGroup "IPv4 Address Tests" [
+    test_most_sig_bit_different1,
+    test_most_sig_bit_different2 ]