asn1-types 0.2.1 → 0.2.2

raw patch · 2 files changed

+31/−18 lines, 2 files

Files

• Data/ASN1/Types/String.hs +30/−17
• asn1-types.cabal +1/−1

@@ -19,6 +19,7 @@ import qualified Data.ByteString as B import qualified Data.ByteString.Char8 as BC import Data.Bits+import Data.Word  -- a note on T61 encodings. The actual specification of a T61 character set seems -- to be lost in time, as such it will be considered an ascii like encoding.@@ -78,23 +79,35 @@     fromString s = ASN1CharacterString UTF8 (encodeUTF8 s)  decodeUTF8 :: ByteString -> String-decodeUTF8 b-    | B.null b  = []-    | otherwise =-        case B.index b 0 of-            v | v `isClear` 7 -> toEnum (fromIntegral v) : decodeUTF8 (B.drop 1 b)-              | v `isClear` 6 -> error "continuation byte"-              | v `isClear` 5 -> uncont 1 (v .&. 0x1f)-              | v `isClear` 4 -> uncont 2 (v .&. 0xf)-              | v `isClear` 3 -> uncont 3 (v .&. 0x7)-              | otherwise     -> error "too many byte"-  where uncont n iniV-            | B.length b < (n+1) = error "cannot decode"-            | otherwise          = let z = flip map [1..n] $ \i ->-                                        case B.index b (i+1) of-                                            v | v `testBit` 7 && v `isClear` 6 -> v .&. 0x3f-                                              | otherwise                      -> error "not a continuation byte"-                                    in (toEnum $ fromIntegral $ foldl (\acc v -> (acc `shiftL` 6) + v) iniV z) : decodeUTF8 (B.drop (1+n) b)+decodeUTF8 b = loop 0 $ B.unpack b+  where loop :: Int -> [Word8] -> [Char]+        loop _   []     = []+        loop pos (x:xs)+            | x `isClear` 7 = toEnum (fromIntegral x) : loop (pos+1) xs+            | x `isClear` 6 = error "continuation byte in heading context"+            | x `isClear` 5 = uncont 1 (x .&. 0x1f) pos xs+            | x `isClear` 4 = uncont 2 (x .&. 0xf)  pos xs+            | x `isClear` 3 = uncont 3 (x .&. 0x7)  pos xs+            | otherwise     = error "too many byte"+        uncont :: Int -> Word8 -> Int -> [Word8] -> [Char]+        uncont 1 iniV pos xs =+            case xs of+                c1:xs' -> decodeCont iniV [c1] : loop (pos+2) xs'+                _      -> error "truncated continuation, expecting 1 byte"+        uncont 2 iniV pos xs =+            case xs of+                c1:c2:xs' -> decodeCont iniV [c1,c2] : loop (pos+3) xs'+                _         -> error "truncated continuation, expecting 2 bytes"+        uncont 3 iniV pos xs =+            case xs of+                c1:c2:c3:xs' -> decodeCont iniV [c1,c2,c3] : loop (pos+4) xs'+                _            -> error "truncated continuation, expecting 3 bytes"+        uncont _ _ _ _ = error "invalid number of bytes for continuation"+        decodeCont :: Word8 -> [Word8] -> Char+        decodeCont iniV l+            | all isContByte l = toEnum $ foldl (\acc v -> (acc `shiftL` 6) + fromIntegral v) (fromIntegral iniV) $ map (\v -> v .&. 0x3f) l+            | otherwise        = error "continuation bytes invalid"+        isContByte v = v `testBit` 7 && v `isClear` 6         isClear v i = not (v `testBit` i)  encodeUTF8 :: String -> ByteString

@@ -1,5 +1,5 @@ Name:                asn1-types-Version:             0.2.1+Version:             0.2.2 Description:         ASN.1 standard types License:             BSD3 License-file:        LICENSE