-import qualified Data.Char as DC
-import qualified Data.List as DL
-import qualified Numeric as N
+import Data.List (intercalate, intersperse)
import System.Exit (exitFailure)
import Text.Regex.Posix
-import ListUtils
-
--- Takes an IP address in CIDR notation, and returns a list of its
--- octets (converted to Int).
-octets :: String -> [Int]
-octets cidr = map read (take 4 (splitWith (`elem` "./") cidr))
-
-
--- Returns the mask portion of a CIDR address. That is, everything
--- after the trailing slash.
-maskbits :: String -> Int
-maskbits cidr = read ((splitWith (`elem` "/") cidr) !! 1)
-
-
--- Takes an Int, and returns its base-two representation as a String.
-base_two :: Int -> String
-base_two n = N.showIntAtBase 2 DC.intToDigit n ""
-
-
--- Takes a set of octets, and converts them to base-two
--- individually. The results are then zero-padded on the left to 8
--- characters, and concatenated together.
-octets_base_two :: [Int] -> String
-octets_base_two octet_list =
- DL.concatMap ((pad_left_to 8 '0') .base_two) octet_list
-
-
--- Returns the minimum address (as a base-two string) satisfying the
--- given CIDR string.
-min_base_two_address :: String -> String
-min_base_two_address cidr =
- pad_right_to 32 '0' netpart
- where
- netpart = take (maskbits cidr) (octets_base_two (octets cidr))
-
-
--- Returns the maximum address (as a base-two string) satisfying the
--- given CIDR string.
-max_base_two_address :: String -> String
-max_base_two_address cidr =
- pad_right_to 32 '1' netpart
- where
- netpart = take (maskbits cidr) (octets_base_two (octets cidr))
-
-
--- The octet components of min_base_two_address, as a base-two String.
-min_base_two_octets :: String -> [String]
-min_base_two_octets cidr =
- [octet1, octet2, octet3, octet4]
- where
- addr = min_base_two_address cidr
- octet1 = fst (DL.splitAt 8 addr)
- octet2 = fst (DL.splitAt 8 (snd (DL.splitAt 8 addr)))
- octet3 = fst (DL.splitAt 8 (snd (DL.splitAt 16 addr)))
- octet4 = snd (DL.splitAt 24 addr)
-
-
--- The octet components of max_base_two_address, as a base-two String.
-max_base_two_octets :: String -> [String]
-max_base_two_octets cidr =
- [octet1, octet2, octet3, octet4]
- where
- addr = max_base_two_address cidr
- octet1 = fst (DL.splitAt 8 addr)
- octet2 = fst (DL.splitAt 8 (snd (DL.splitAt 8 addr)))
- octet3 = fst (DL.splitAt 8 (snd (DL.splitAt 16 addr)))
- octet4 = snd (DL.splitAt 24 addr)
-
-
--- The octet components of min_base_two_address, as Ints.
-min_octets :: String -> [Int]
-min_octets cidr =
- map base_two_to_base_ten (min_base_two_octets cidr)
-
-
--- The octet components of max_base_two_address, as Ints.
-max_octets :: String -> [Int]
-max_octets cidr =
- map base_two_to_base_ten (max_base_two_octets cidr)
-
-
--- The base_two_to_base_ten function requires a way to determine
--- whether or not the character it's currently parsing is valid. This
--- should do it.
-is_binary_digit :: Char -> Bool
-is_binary_digit c =
- if c `elem` ['0','1'] then
- True
- else
- False
-
-
--- Convert a base-two String to an Int.
-base_two_to_base_ten :: String -> Int
-base_two_to_base_ten s =
- if (length parsed) == 0 then
- 0
- else
- fst (parsed !! 0)
- where
- parsed = N.readInt 2 is_binary_digit DC.digitToInt s
+import Cidr (Cidr,
+ from_string,
+ min_first_octet,
+ min_second_octet,
+ min_third_octet,
+ min_fourth_octet,
+ max_first_octet,
+ max_second_octet,
+ max_third_octet,
+ max_fourth_octet)
-- A regular expression that matches a non-address character.
-- max values.
-- 4. Join the regexes from step 3 with regexes matching periods.
-- 5. Stick an address boundary on either side of the result.
-cidr_to_regex :: String -> String
+--cidr_to_regex :: String -> String
+cidr_to_regex :: Cidr.Cidr -> String
cidr_to_regex cidr =
- addr_barrier (DL.intercalate "\\." [range1, range2, range3, range4])
+ addr_barrier (intercalate "\\." [range1, range2, range3, range4])
where
range1 = numeric_range min1 max1
range2 = numeric_range min2 max2
range3 = numeric_range min3 max3
range4 = numeric_range min4 max4
- min1 = (min_octets cidr) !! 0
- min2 = (min_octets cidr) !! 1
- min3 = (min_octets cidr) !! 2
- min4 = (min_octets cidr) !! 3
- max1 = (max_octets cidr) !! 0
- max2 = (max_octets cidr) !! 1
- max3 = (max_octets cidr) !! 2
- max4 = (max_octets cidr) !! 3
+ min1 = min_first_octet cidr
+ min2 = min_second_octet cidr
+ min3 = min_third_octet cidr
+ min4 = min_fourth_octet cidr
+ max1 = max_first_octet cidr
+ max2 = max_second_octet cidr
+ max3 = max_third_octet cidr
+ max4 = max_fourth_octet cidr
-- Will return True if the passed String is in CIDR notation, False
-- Take a list of Strings, and return a regular expression matching
-- any of them.
alternate :: [String] -> String
-alternate terms = "(" ++ (concat (DL.intersperse "|" terms)) ++ ")"
+alternate terms = "(" ++ (concat (intersperse "|" terms)) ++ ")"
-- Take two Ints as parameters, and return a regex matching any
main :: IO ()
main = do
input <- getContents
- let cidrs = lines input
- mapM validate_or_die cidrs
+ let cidr_strings = lines input
+ mapM validate_or_die cidr_strings
+ let cidrs = map Cidr.from_string cidr_strings
let regexes = map cidr_to_regex cidrs
putStrLn $ alternate regexes