module Octet where
+import Test.HUnit
+import Test.QuickCheck
+
import Bit
-- An Octet consists of eight bits. For our purposes, the most
b6 :: Bit,
b7 :: Bit,
b8 :: Bit }
- deriving (Eq, Show)
+ deriving (Eq)
+
+
+instance Show Octet where
+ show Octet.None = "None"
+ show oct = show (octet_to_int oct)
+
+
+instance Arbitrary Octet where
+ arbitrary = do
+ a1 <- arbitrary :: Gen Bit
+ a2 <- arbitrary :: Gen Bit
+ a3 <- arbitrary :: Gen Bit
+ a4 <- arbitrary :: Gen Bit
+ a5 <- arbitrary :: Gen Bit
+ a6 <- arbitrary :: Gen Bit
+ a7 <- arbitrary :: Gen Bit
+ a8 <- arbitrary :: Gen Bit
+ return (Octet a1 a2 a3 a4 a5 a6 a7 a8)
+
+ coarbitrary _ = variant 0
+
-- Convert each bit to its integer value, and multiply by the
-- appropriate power of two. Sum them up, and we should get an integer
8 * (bit_to_int (b5 x)) +
4 * (bit_to_int (b6 x)) +
2 * (bit_to_int (b7 x)) +
- 0 * (bit_to_int (b8 x))
+ 1 * (bit_to_int (b8 x))
| (x < 0) || (x > 255) = Octet.None
| otherwise = (Octet a1 a2 a3 a4 a5 a6 a7 a8)
where
- a1 = if (x `mod` 128) > 0 then One else Zero
- a2 = if (x `mod` 64) > 0 then One else Zero
- a3 = if (x `mod` 32) > 0 then One else Zero
- a4 = if (x `mod` 16) > 0 then One else Zero
- a5 = if (x `mod` 8) > 0 then One else Zero
- a6 = if (x `mod` 4) > 0 then One else Zero
- a7 = if (x `mod` 2) > 0 then One else Zero
- a8 = if (x `mod` 1) > 0 then One else Zero
+ a1 = if (x >= 128) then One else Zero
+ a2 = if ((x `mod` 128) >= 64) then One else Zero
+ a3 = if ((x `mod` 64) >= 32) then One else Zero
+ a4 = if ((x `mod` 32) >= 16) then One else Zero
+ a5 = if ((x `mod` 16) >= 8) then One else Zero
+ a6 = if ((x `mod` 8) >= 4) then One else Zero
+ a7 = if ((x `mod` 4) >= 2) then One else Zero
+ a8 = if ((x `mod` 2) == 1) then One else Zero
octet_from_string :: String -> Octet
-- The octet with the greatest possible value.
max_octet :: Octet
max_octet = Octet One One One One One One One One
+
+
+
+-- HUnit Tests
+test_octet_from_int1 :: Test
+test_octet_from_int1 =
+ TestCase $ assertEqual "octet_from_int 128 should parse as 10000000" oct1 (octet_from_int 128)
+ where
+ oct1 = Octet One Zero Zero Zero Zero Zero Zero Zero
+
+
+octet_tests :: [Test]
+octet_tests = [ test_octet_from_int1 ]