X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FParser.hs;h=c43dfa7616d758bd2d5776c803cc435a56f0fd22;hb=b340a77fa7bd051dd13a41d0a5b1ad30220bc6b6;hp=7a51ddcab435aa75cfcfc2904370bd104f8caef9;hpb=9961a721f98b101825ef154a2122c1fc2fa6d1ac;p=Lucu.git diff --git a/Network/HTTP/Lucu/Parser.hs b/Network/HTTP/Lucu/Parser.hs index 7a51ddc..c43dfa7 100644 --- a/Network/HTTP/Lucu/Parser.hs +++ b/Network/HTTP/Lucu/Parser.hs @@ -1,19 +1,32 @@ module Network.HTTP.Lucu.Parser ( Parser(..) - , parse -- Parser a -> ByteString -> Maybe (a, ByteString) + , ParserResult(..) + + , parse -- Parser a -> ByteString -> (ParserResult a, ByteString) + , parseStr -- Parser a -> String -> (ParserResult a, ByteString) + , anyChar -- Parser Char + , eof -- Parser () + , allowEOF -- Parser a -> Parser a , satisfy -- (Char -> Bool) -> Parser Char , char -- Char -> Parser Char , string -- String -> Parser String , (<|>) -- Parser a -> Parser a -> Parser a , oneOf -- [Char] -> Parser Char , digit -- Parser Char + , hexDigit -- Parser Char , notFollowedBy -- Parser a -> Parser () , many -- Parser a -> Parser [a] , many1 -- Parser a -> Parser [a] , manyTill -- Parser a -> Parser end -> Parser [a] , many1Till -- Parser a -> Parser end -> Parser [a] + , count -- Int -> Parser a -> Parser [a] + , option -- a -> Parser a -> Parser a + , sepBy -- Parser a -> Parser sep -> Parser [a] + , sepBy1 -- Parser a -> Parser sep -> Parser [a] + , sp -- Parser Char + , ht -- Parser Char , crlf -- Parser String ) where @@ -24,36 +37,74 @@ import qualified Data.ByteString.Lazy.Char8 as B import Data.ByteString.Lazy.Char8 (ByteString) data Parser a = Parser { - runParser :: State ByteString (Maybe a) + runParser :: State ParserState (ParserResult a) } +type ParserState = (ByteString, IsEOFFatal) + +type IsEOFFatal = Bool + +data ParserResult a = Success a + | IllegalInput -- 受理出來ない入力があった + | ReachedEOF -- 限界を越えて讀まうとした + deriving (Eq, Show) + -- (>>=) :: Parser a -> (a -> Parser b) -> Parser b instance Monad Parser where - p >>= f = Parser $ do saved <- get -- 失敗した時の爲に状態を保存 + p >>= f = Parser $ do saved@(_, isEOFFatal) <- get -- 失敗した時の爲に状態を保存 result <- runParser p case result of - Just a -> runParser (f a) - Nothing -> do put saved -- 状態を復歸 - return Nothing - return = Parser . return . Just - fail _ = Parser $ return Nothing + Success a -> runParser (f a) + IllegalInput -> do put saved -- 状態を復歸 + return IllegalInput + ReachedEOF -> if isEOFFatal then + return ReachedEOF + else + do put saved + return IllegalInput + return = Parser . return . Success + fail _ = Parser $ return IllegalInput + +parse :: Parser a -> ByteString -> (ParserResult a, ByteString) +parse p input = let (result, (input', _)) = runState (runParser p) (input, True) + in + (result, input') -parse :: Parser a -> ByteString -> Maybe (a, ByteString) -parse p input = case runState (runParser p) input of - (Just a , input') -> Just (a, input') - (Nothing, _ ) -> Nothing + +parseStr :: Parser a -> String -> (ParserResult a, ByteString) +parseStr p input = parse p $ B.pack input anyChar :: Parser Char -anyChar = Parser $ do input <- get +anyChar = Parser $ do (input, isEOFFatal) <- get if B.null input then - return Nothing + return ReachedEOF else do let c = B.head input - put (B.tail input) - return (Just c) + put (B.tail input, isEOFFatal) + return (Success c) + + +eof :: Parser () +eof = Parser $ do (input, _) <- get + if B.null input then + return $ Success () + else + return IllegalInput + + +allowEOF :: Parser a -> Parser a +allowEOF f = Parser $ do (input, isEOFFatal) <- get + put (input, False) + + result <- runParser f + + (input', _) <- get + put (input', isEOFFatal) + + return result satisfy :: (Char -> Bool) -> Parser Char @@ -74,12 +125,17 @@ string str = do mapM_ char str infixr 0 <|> (<|>) :: Parser a -> Parser a -> Parser a -f <|> g = Parser $ do saved <- get -- 状態を保存 +f <|> g = Parser $ do saved@(_, isEOFFatal) <- get -- 状態を保存 result <- runParser f case result of - Just a -> return (Just a) - Nothing -> do put saved -- 状態を復歸 - runParser g + Success a -> return $ Success a + IllegalInput -> do put saved -- 状態を復歸 + runParser g + ReachedEOF -> if isEOFFatal then + return ReachedEOF + else + do put saved + runParser g oneOf :: [Char] -> Parser Char @@ -91,7 +147,21 @@ notFollowedBy p = p >>= fail "" <|> return () digit :: Parser Char -digit = oneOf "0123456789" +digit = do c <- anyChar + if c >= '0' && c <= '9' then + return c + else + fail "" + + +hexDigit :: Parser Char +hexDigit = do c <- anyChar + if (c >= '0' && c <= '9') || + (c >= 'a' && c <= 'f') || + (c >= 'A' && c <= 'F') then + return c + else + fail "" many :: Parser a -> Parser [a] @@ -121,9 +191,34 @@ many1Till p end = many1 $ do x <- p return x +count :: Int -> Parser a -> Parser [a] +count 0 _ = return [] +count n p = do x <- p + xs <- count (n-1) p + return (x:xs) + + +option :: a -> Parser a -> Parser a +option def p = p <|> return def + + +sepBy :: Parser a -> Parser sep -> Parser [a] +sepBy p sep = sepBy1 p sep <|> return [] + + +sepBy1 :: Parser a -> Parser sep -> Parser [a] +sepBy1 p sep = do x <- p + xs <- many $ sep >> p + return (x:xs) + + sp :: Parser Char sp = char ' ' +ht :: Parser Char +ht = char '\t' + + crlf :: Parser String crlf = string "\x0d\x0a"