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Diffstat (limited to 'MIME/Base64.hs')
| -rw-r--r-- | MIME/Base64.hs | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/MIME/Base64.hs b/MIME/Base64.hs deleted file mode 100644 index 848e034..0000000 --- a/MIME/Base64.hs +++ /dev/null @@ -1,141 +0,0 @@ -{- | - - Module : MIME.Parse - Copyright : (c) 2006 - - Maintainer : - Stability : unstable - Portability : GHC - - Base64 decoding and encoding routines. --} -module MIME.Base64 - ( encodeRaw -- :: Bool -> String -> [Word8] - , encodeRawString -- :: Bool -> String -> String - , encodeRawPrim -- :: Bool -> Char -> Char -> [Word8] -> String - - , formatOutput -- :: Int -> Maybe String -> String -> String - - , decode -- :: String -> [Word8] - , decodeToString -- :: String -> String - , decodePrim -- :: Char -> Char -> String -> [Word8] - ) where - -import Data.Bits -import Data.Char -import Data.Word -import Data.Maybe - -encodeRawString :: Bool -> String -> String -encodeRawString trail xs = encodeRaw trail (map (fromIntegral.ord) xs) - --- | 'formatOutput n mbLT str' formats 'str', splitting it --- into lines of length 'n'. The optional value lets you control what --- line terminator sequence to use; the default is CRLF (as per MIME.) -formatOutput :: Int -> Maybe String -> String -> String -formatOutput n mbTerm str - | n <= 0 = error ("formatOutput: negative line length " ++ show n) - | otherwise = chop n str - where - crlf :: String - crlf = fromMaybe "\r\n" mbTerm - - chop _ "" = "" - chop i xs = - case splitAt i xs of - (as,"") -> as - (as,bs) -> as ++ crlf ++ chop i bs - -encodeRaw :: Bool -> [Word8] -> String -encodeRaw trail bs = encodeRawPrim trail '+' '/' bs - --- lets you control what non-alphanum characters to use --- (The base64url variation uses '*' and '-', for instance.) --- No support for mapping these to multiple characters in the output though. -encodeRawPrim :: Bool -> Char -> Char -> [Word8] -> String -encodeRawPrim trail ch62 ch63 ls = encoder ls - where - trailer xs ys - | not trail = xs - | otherwise = xs ++ ys - f = fromB64 ch62 ch63 - encoder [] = [] - encoder [x] = trailer (take 2 (encode3 f x 0 0 "")) "==" - encoder [x,y] = trailer (take 3 (encode3 f x y 0 "")) "=" - encoder (x:y:z:ws) = encode3 f x y z (encoder ws) - -encode3 :: (Word8 -> Char) -> Word8 -> Word8 -> Word8 -> String -> String -encode3 f a b c rs = - f (low6 (w24 `shiftR` 18)) : - f (low6 (w24 `shiftR` 12)) : - f (low6 (w24 `shiftR` 6)) : - f (low6 w24) : rs - where - w24 :: Word32 - w24 = (fromIntegral a `shiftL` 16) + - (fromIntegral b `shiftL` 8) + - fromIntegral c - -decodeToString :: String -> String -decodeToString str = map (chr.fromIntegral) $ decode str - -decode :: String -> [Word8] -decode str = decodePrim '+' '/' str - -decodePrim :: Char -> Char -> String -> [Word8] -decodePrim ch62 ch63 str = decoder $ takeUntilEnd str - where - takeUntilEnd "" = [] - takeUntilEnd ('=':_) = [] - takeUntilEnd (x:xs) = - case toB64 ch62 ch63 x of - Nothing -> takeUntilEnd xs - Just b -> b : takeUntilEnd xs - -decoder :: [Word8] -> [Word8] -decoder [] = [] -decoder [x] = take 1 (decode4 x 0 0 0 []) -decoder [x,y] = take 1 (decode4 x y 0 0 []) -- upper 4 bits of second val are known to be 0. -decoder [x,y,z] = take 2 (decode4 x y z 0 []) -decoder (x:y:z:w:xs) = decode4 x y z w (decoder xs) - -decode4 :: Word8 -> Word8 -> Word8 -> Word8 -> [Word8] -> [Word8] -decode4 a b c d rs = - (lowByte (w24 `shiftR` 16)) : - (lowByte (w24 `shiftR` 8)) : - (lowByte w24) : rs - where - w24 :: Word32 - w24 = - (fromIntegral a) `shiftL` 18 .|. - (fromIntegral b) `shiftL` 12 .|. - (fromIntegral c) `shiftL` 6 .|. - (fromIntegral d) - -toB64 :: Char -> Char -> Char -> Maybe Word8 -toB64 a b ch - | ch >= 'A' && ch <= 'Z' = Just (fromIntegral (ord ch - ord 'A')) - | ch >= 'a' && ch <= 'z' = Just (26 + fromIntegral (ord ch - ord 'a')) - | ch >= '0' && ch <= '9' = Just (52 + fromIntegral (ord ch - ord '0')) - | ch == a = Just 62 - | ch == b = Just 63 - | otherwise = Nothing - -fromB64 :: Char -> Char -> Word8 -> Char -fromB64 ch62 ch63 x - | x < 26 = chr (ord 'A' + xi) - | x < 52 = chr (ord 'a' + (xi-26)) - | x < 62 = chr (ord '0' + (xi-52)) - | x == 62 = ch62 - | x == 63 = ch63 - | otherwise = error ("fromB64: index out of range " ++ show x) - where - xi :: Int - xi = fromIntegral x - -low6 :: Word32 -> Word8 -low6 x = fromIntegral (x .&. 0x3f) - -lowByte :: Word32 -> Word8 -lowByte x = (fromIntegral x) .&. 0xff - |