X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FParser.hs;h=f99cdf58b5afdd5c2d2a610e1ee3786e056c221d;hb=cd1b58b84ff354e3fc2a7d2c8fd548a7b59fe138;hp=7a51ddcab435aa75cfcfc2904370bd104f8caef9;hpb=9961a721f98b101825ef154a2122c1fc2fa6d1ac;p=Lucu.git

diff --git a/Network/HTTP/Lucu/Parser.hs b/Network/HTTP/Lucu/Parser.hs
index 7a51ddc..f99cdf5 100644
--- a/Network/HTTP/Lucu/Parser.hs
+++ b/Network/HTTP/Lucu/Parser.hs
@@ -1,6 +1,9 @@
 module Network.HTTP.Lucu.Parser
     ( Parser(..)
-    , parse     -- Parser a -> ByteString -> Maybe (a, ByteString)
+    , ParserResult(..)
+
+    , parse     -- Parser a -> ByteString -> ParserResult a
+
     , anyChar   -- Parser Char
     , satisfy   -- (Char -> Bool) -> Parser Char
     , char      -- Char -> Parser Char
@@ -8,12 +11,15 @@ module Network.HTTP.Lucu.Parser
     , (<|>)     -- 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]
+    , option    -- a -> Parser a -> Parser a
     , sp        -- Parser Char
+    , ht        -- Parser Char
     , crlf      -- Parser String
     )
     where
@@ -24,36 +30,40 @@ 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 ByteString (ParserResult a)
     }
 
+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
                           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   -> return ReachedEOF
+    return = Parser . return . Success
+    fail _ = Parser $ return IllegalInput
 
 
-parse :: Parser a -> ByteString -> Maybe (a, ByteString)
-parse p input = case runState (runParser p) input of
-                  (Just a , input') -> Just (a, input')
-                  (Nothing, _     ) -> Nothing
+parse :: Parser a -> ByteString -> (ParserResult a, ByteString)
+parse p input = runState (runParser p) input
 
 
 anyChar :: Parser Char
 anyChar = Parser $ do input <- get
                       if B.null input then
-                          return Nothing
+                          return ReachedEOF
                         else
                           do let c = B.head input
                              put (B.tail input)
-                             return (Just c)
+                             return (Success c)
 
 
 satisfy :: (Char -> Bool) -> Parser Char
@@ -77,9 +87,10 @@ infixr 0 <|>
 f <|> g = Parser $ do saved  <- 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   -> return ReachedEOF
 
 
 oneOf :: [Char] -> Parser Char
@@ -91,7 +102,21 @@ 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 +146,17 @@ many1Till p end = many1 $ do x <- p
                              return x
 
 
+option :: a -> Parser a -> Parser a
+option def p = p <|> return def
+
+
 sp :: Parser Char
 sp = char ' '
 
 
+ht :: Parser Char
+ht = char '\t'
+
+
 crlf :: Parser String
 crlf = string "\x0d\x0a"