+{-# LANGUAGE
+ BangPatterns
+ , OverloadedStrings
+ , UnicodeSyntax
+ #-}
-- |Utility functions used internally in the Lucu httpd. These
-- functions may be useful too for something else.
module Network.HTTP.Lucu.Utils
( splitBy
, joinWith
- , trim
- , noCaseEq
- , noCaseEq'
- , isWhiteSpace
, quoteStr
, parseWWWFormURLEncoded
)
where
-
-import Control.Monad.Trans
-import Data.Char
-import Data.List
-import Foreign
-import Foreign.C
+import Control.Monad
+import Data.Ascii (Ascii, AsciiBuilder)
+import qualified Data.Ascii as A
+import qualified Data.ByteString.Char8 as BS
+import Data.List hiding (last)
+import Data.Monoid.Unicode
import Network.URI
+import Prelude hiding (last)
+import Prelude.Unicode
-- |> splitBy (== ':') "ab:c:def"
-- > ==> ["ab", "c", "def"]
-splitBy :: (a -> Bool) -> [a] -> [[a]]
-splitBy isSeparator src
- = isSeparator `seq`
- case break isSeparator src
- of (last , [] ) -> last : []
- (first, sep:rest) -> first : splitBy isSeparator rest
+splitBy ∷ (a → Bool) → [a] → [[a]]
+splitBy isSep src
+ = case break isSep src
+ of (last , [] ) → [last]
+ (first, _sep:rest) → first : splitBy isSep rest
--- |> joinWith ':' ["ab", "c", "def"]
+-- |> joinWith ":" ["ab", "c", "def"]
-- > ==> "ab:c:def"
-joinWith :: [a] -> [[a]] -> [a]
-joinWith separator xs
- = separator `seq` xs `seq`
- foldr (++) [] $! intersperse separator xs
-
--- |> trim (== '_') "__ab_c__def___"
--- > ==> "ab_c__def"
-trim :: (a -> Bool) -> [a] -> [a]
-trim p = p `seq` trimTail . trimHead
+joinWith ∷ Ascii → [AsciiBuilder] → AsciiBuilder
+{-# INLINEABLE joinWith #-}
+joinWith sep = flip go (∅)
where
- trimHead = dropWhile p
- trimTail = reverse . trimHead . reverse
-
--- |@'noCaseEq' a b@ is equivalent to @(map toLower a) == (map toLower
--- b)@. See 'noCaseEq''.
-noCaseEq :: String -> String -> Bool
-noCaseEq a b
- = (map toLower a) == (map toLower b)
-{-# INLINE noCaseEq #-}
-
--- |@'noCaseEq'' a b@ is a variant of 'noCaseEq' which first checks
--- the length of two strings to avoid possibly unnecessary comparison.
-noCaseEq' :: String -> String -> Bool
-noCaseEq' a b
- | length a /= length b = False
- | otherwise = noCaseEq a b
-{-# INLINE noCaseEq' #-}
-
--- |@'isWhiteSpace' c@ is True iff c is one of SP, HT, CR and LF.
-isWhiteSpace :: Char -> Bool
-isWhiteSpace ' ' = True
-isWhiteSpace '\t' = True
-isWhiteSpace '\r' = True
-isWhiteSpace '\n' = True
-isWhiteSpace _ = False
-{-# INLINE isWhiteSpace #-}
+ go ∷ [AsciiBuilder] → AsciiBuilder → AsciiBuilder
+ {-# INLINE go #-}
+ go [] ab = ab
+ go (x:[]) ab = ab ⊕ x
+ go (x:xs) ab = go xs (ab ⊕ A.toAsciiBuilder sep ⊕ x)
-- |> quoteStr "abc"
-- > ==> "\"abc\""
--
-- > quoteStr "ab\"c"
-- > ==> "\"ab\\\"c\""
-quoteStr :: String -> String
-quoteStr str = str `seq`
- foldr (++) "" (["\""] ++ map quote str ++ ["\""])
+quoteStr ∷ Ascii → AsciiBuilder
+quoteStr str = A.toAsciiBuilder "\"" ⊕
+ go (A.toByteString str) (∅) ⊕
+ A.toAsciiBuilder "\""
where
- quote :: Char -> String
- quote '"' = "\\\""
- quote c = [c]
+ go ∷ BS.ByteString → AsciiBuilder → AsciiBuilder
+ go bs ab
+ = case BS.break (≡ '"') bs of
+ (x, y)
+ | BS.null y → ab ⊕ b2ab x
+ | otherwise → go (BS.tail y) (ab ⊕ b2ab x
+ ⊕ A.toAsciiBuilder "\\\"")
+ b2ab ∷ BS.ByteString → AsciiBuilder
+ b2ab = A.toAsciiBuilder ∘ A.unsafeFromByteString
-- |> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
-- > ==> [("aaa", "bbb"), ("ccc", "ddd")]
-parseWWWFormURLEncoded :: String -> [(String, String)]
+parseWWWFormURLEncoded ∷ String → [(String, String)]
parseWWWFormURLEncoded src
| src == "" = []
- | otherwise = do pairStr <- splitBy (\ c -> c == ';' || c == '&') src
+ | otherwise = do pairStr <- splitBy (\ c → c == ';' || c == '&') src
let (key, value) = break (== '=') pairStr
return ( unEscapeString key
, unEscapeString $ case value of
- ('=':val) -> val
- "" -> ""
+ ('=':val) → val
+ val → val
)