module IPv4Address(
+ IPv4Address(..),
ipv4address_properties,
ipv4address_tests,
- IPv4Address(..),
- most_sig_bit_different,
-) where
+ most_sig_bit_different )
+where
-import Data.Maybe (fromJust)
import Test.HUnit (assertEqual)
import Test.Framework (Test, testGroup)
import Test.Framework.Providers.HUnit (testCase)
import Test.Framework.Providers.QuickCheck2 (testProperty)
import Test.QuickCheck (Arbitrary(..), Gen, Property, (==>))
-import Maskable
-import Maskbits
-import Octet
+import Maskable (Maskable(..))
+import Maskbits (Maskbits(..))
+import Octet (Octet(..))
data IPv4Address =
IPv4Address { octet1 :: Octet,
--- | Convert @addr@ to an 'Int' by converting each octet to an 'Int'
--- and shifting the result to the left by 0,8.16, or 24 bits.
-ipv4address_to_int :: IPv4Address -> Int
-ipv4address_to_int addr =
- (shifted_oct1) + (shifted_oct2) + (shifted_oct3) + oct4
- where
- oct1 = octet_to_int (octet1 addr)
- oct2 = octet_to_int (octet2 addr)
- oct3 = octet_to_int (octet3 addr)
- oct4 = octet_to_int (octet4 addr)
-
- shifted_oct1 = oct1 * 2^(24 :: Integer)
- shifted_oct2 = oct2 * 2^(16 :: Integer)
- shifted_oct3 = oct3 * 2^(8 :: Integer)
-
-
-
--- | Convert an 'Int' @x@ to an 'IPv4Address'. Each octet of @x@ is
--- right-shifted by the appropriate number of bits, and the fractional
--- part is dropped.
-ipv4address_from_int :: Int -> Maybe IPv4Address
-ipv4address_from_int x
- | (x < 0) || (x > 2^(32 :: Integer) - 1) = Nothing
- | otherwise = do
- -- If the algebra is right, none of these octet_from_int calls
- -- below can fail since 0 <= x <= 2^32 - 1.
- oct1 <- octet_from_int shifted_x1
- oct2 <- octet_from_int shifted_x2
- oct3 <- octet_from_int shifted_x3
- oct4 <- octet_from_int x4
- return $ IPv4Address oct1 oct2 oct3 oct4
- where
- -- Chop off the higher octets. x1 = x `mod` 2^32, would be
- -- redundant.
- x2 = x `mod` 2^(24 :: Integer)
- x3 = x `mod` 2^(16 :: Integer)
- x4 = x `mod` 2^(8 :: Integer)
- -- Perform right-shifts. x4 doesn't need a shift.
- shifted_x1 = x `quot` 2^(24 :: Integer)
- shifted_x2 = x2 `quot` 2^(16 :: Integer)
- shifted_x3 = x3 `quot` 2^(8 :: Integer)
-
instance Enum IPv4Address where
- -- We're supposed to throw a runtime error if you call (succ
- -- maxBound), so the fromJust here doesn't introduce any additional
- -- badness.
- toEnum = fromJust . ipv4address_from_int
- fromEnum = ipv4address_to_int
+ -- | Convert an 'Int' @x@ to an 'IPv4Address'. Each octet of @x@ is
+ -- right-shifted by the appropriate number of bits, and the fractional
+ -- part is dropped.
+ toEnum x =
+ IPv4Address oct1 oct2 oct3 oct4
+ where
+ -- Chop off the higher octets. x1 = x `mod` 2^32, would be
+ -- redundant.
+ x2 = x `mod` 2^(24 :: Integer)
+ x3 = x `mod` 2^(16 :: Integer)
+ x4 = x `mod` 2^(8 :: Integer)
+ -- Perform right-shifts. x4 doesn't need a shift.
+ shifted_x1 = x `quot` 2^(24 :: Integer)
+ shifted_x2 = x2 `quot` 2^(16 :: Integer)
+ shifted_x3 = x3 `quot` 2^(8 :: Integer)
+ oct1 = toEnum shifted_x1
+ oct2 = toEnum shifted_x2
+ oct3 = toEnum shifted_x3
+ oct4 = toEnum x4
+
+ -- | Convert @addr@ to an 'Int' by converting each octet to an 'Int'
+ -- and shifting the result to the left by 0,8.16, or 24 bits.
+ fromEnum addr =
+ (shifted_oct1) + (shifted_oct2) + (shifted_oct3) + oct4
+ where
+ oct1 = fromEnum (octet1 addr)
+ oct2 = fromEnum (octet2 addr)
+ oct3 = fromEnum (octet3 addr)
+ oct4 = fromEnum (octet4 addr)
+ shifted_oct1 = oct1 * 2^(24 :: Integer)
+ shifted_oct2 = oct2 * 2^(16 :: Integer)
+ shifted_oct3 = oct3 * 2^(8 :: Integer)
-- | Given two addresses, find the number of the most significant bit
-- where they differ. If the addresses are the same, return
test_maxBound,
test_minBound,
test_most_sig_bit_different1,
- test_most_sig_bit_different2 ]
+ test_most_sig_bit_different2,
+ test_to_enum ]
ipv4address_properties :: Test
ipv4address_properties =
mk_testaddr a b c 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
+ oct1 = toEnum a
+ oct2 = toEnum b
+ oct3 = toEnum c
+ oct4 = toEnum d
test_minBound :: Test
test_minBound =
bit = most_sig_bit_different addr1 addr2
+test_to_enum :: Test
+test_to_enum =
+ testCase desc $ assertEqual desc expected actual
+ where
+ desc = "192.168.0.0 in base-10 is 3232235520"
+ expected = mk_testaddr 192 168 0 0
+ actual = toEnum 3232235520