X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FOctet.hs;h=ceeb4b8ff2ddd9e3c047ab78924f7f7b206d6ef8;hb=4520812e6f264cdeba984d180f20a8f8c6b6d645;hp=b3e6a0f5d3c1310f38443ca99dc49c43de516e5a;hpb=c5ea6135a25e8c9e108c34ebb0d0cbb4b4af1e6d;p=hath.git diff --git a/src/Octet.hs b/src/Octet.hs index b3e6a0f..ceeb4b8 100644 --- a/src/Octet.hs +++ b/src/Octet.hs @@ -3,7 +3,9 @@ module Octet where import Test.HUnit import Test.QuickCheck -import Bit +import Bit as B +import Maskable +import Maskbits -- An Octet consists of eight bits. For our purposes, the most -- significant bit will come "first." That is, b1 is in the 2^7 @@ -39,6 +41,22 @@ instance Arbitrary Octet where coarbitrary _ = variant 0 +instance Maskable Octet where + apply_mask _ Maskbits.None = Octet.None + apply_mask Octet.None _ = Octet.None + apply_mask oct mask + | mask == Eight = oct + | mask == Seven = oct { b8 = B.Zero } + | mask == Six = oct { b8 = B.Zero, b7 = B.Zero } + | mask == Five = oct { b8 = B.Zero, b7 = B.Zero, b6 = B.Zero } + | mask == Four = oct { b8 = B.Zero, b7 = B.Zero, b6 = B.Zero, b5 = B.Zero } + | mask == Three = oct { b8 = B.Zero, b7 = B.Zero, b6 = B.Zero, b5 = B.Zero, b4 = B.Zero } + | mask == Two = oct { b8 = B.Zero, b7 = B.Zero, b6 = B.Zero, b5 = B.Zero, b4 = B.Zero, b3 = B.Zero } + | mask == Maskbits.One = oct { b8 = B.Zero, b7 = B.Zero, b6 = B.Zero, b5 = B.Zero, b4 = B.Zero, b3 = B.Zero, b2 = B.Zero } + | mask == Maskbits.Zero = min_octet + | otherwise = Octet.None + + -- Convert each bit to its integer value, and multiply by the -- appropriate power of two. Sum them up, and we should get an integer -- between 0 and 255. @@ -60,14 +78,14 @@ octet_from_int x | (x < 0) || (x > 255) = Octet.None | otherwise = (Octet a1 a2 a3 a4 a5 a6 a7 a8) where - 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 + a1 = if (x >= 128) then B.One else B.Zero + a2 = if ((x `mod` 128) >= 64) then B.One else B.Zero + a3 = if ((x `mod` 64) >= 32) then B.One else B.Zero + a4 = if ((x `mod` 32) >= 16) then B.One else B.Zero + a5 = if ((x `mod` 16) >= 8) then B.One else B.Zero + a6 = if ((x `mod` 8) >= 4) then B.One else B.Zero + a7 = if ((x `mod` 4) >= 2) then B.One else B.Zero + a8 = if ((x `mod` 2) == 1) then B.One else B.Zero octet_from_string :: String -> Octet @@ -79,12 +97,12 @@ octet_from_string s = -- The octet with the least possible value. min_octet :: Octet -min_octet = Octet Zero Zero Zero Zero Zero Zero Zero Zero +min_octet = Octet B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero -- The octet with the greatest possible value. max_octet :: Octet -max_octet = Octet One One One One One One One One +max_octet = Octet B.One B.One B.One B.One B.One B.One B.One B.One @@ -93,8 +111,26 @@ 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 + oct1 = Octet B.One B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero + + +test_octet_mask1 :: Test +test_octet_mask1 = + TestCase $ assertEqual "The network bits of 255/4 should equal 240" oct2 (apply_mask oct1 Four) + where + oct1 = octet_from_int 255 + oct2 = octet_from_int 240 + + +test_octet_mask2 :: Test +test_octet_mask2 = + TestCase $ assertEqual "The network bits of 255/1 should equal 128" oct2 (apply_mask oct1 Maskbits.One) + where + oct1 = octet_from_int 255 + oct2 = octet_from_int 128 octet_tests :: [Test] -octet_tests = [ test_octet_from_int1 ] +octet_tests = [ test_octet_from_int1, + test_octet_mask1, + test_octet_mask2 ]