{-# LANGUAGE Trustworthy #-} {-# LANGUAGE NoImplicitPrelude , BangPatterns , NondecreasingIndentation , MagicHash #-} {-# OPTIONS_GHC -funbox-strict-fields #-} ----------------------------------------------------------------------------- -- | -- Module : GHC.IO.Encoding.UTF8 -- Copyright : (c) The University of Glasgow, 2009 -- License : see libraries/base/LICENSE -- -- Maintainer : libraries@haskell.org -- Stability : internal -- Portability : non-portable -- -- UTF-8 Codec for the IO library -- -- This is one of several UTF-8 implementations provided by GHC; see Note -- [GHC's many UTF-8 implementations] in "GHC.Encoding.UTF8" for an -- overview. -- -- Portions Copyright : (c) Tom Harper 2008-2009, -- (c) Bryan O'Sullivan 2009, -- (c) Duncan Coutts 2009 -- ----------------------------------------------------------------------------- module GHC.IO.Encoding.UTF8 ( utf8, mkUTF8, utf8_bom, mkUTF8_bom ) where import GHC.Base import GHC.Real import GHC.Num import GHC.IORef -- import GHC.IO import GHC.IO.Buffer import GHC.IO.Encoding.Failure import GHC.IO.Encoding.Types import GHC.Word import Data.Bits utf8 :: TextEncoding utf8 = mkUTF8 ErrorOnCodingFailure -- | @since 4.4.0.0 mkUTF8 :: CodingFailureMode -> TextEncoding mkUTF8 cfm = TextEncoding { textEncodingName = "UTF-8", mkTextDecoder = utf8_DF cfm, mkTextEncoder = utf8_EF cfm } utf8_DF :: CodingFailureMode -> IO (TextDecoder ()) utf8_DF cfm = return (BufferCodec { encode = utf8_decode, recover = recoverDecode cfm, close = return (), getState = return (), setState = const $ return () }) utf8_EF :: CodingFailureMode -> IO (TextEncoder ()) utf8_EF cfm = return (BufferCodec { encode = utf8_encode, recover = recoverEncode cfm, close = return (), getState = return (), setState = const $ return () }) utf8_bom :: TextEncoding utf8_bom = mkUTF8_bom ErrorOnCodingFailure mkUTF8_bom :: CodingFailureMode -> TextEncoding mkUTF8_bom cfm = TextEncoding { textEncodingName = "UTF-8BOM", mkTextDecoder = utf8_bom_DF cfm, mkTextEncoder = utf8_bom_EF cfm } utf8_bom_DF :: CodingFailureMode -> IO (TextDecoder Bool) utf8_bom_DF cfm = do ref <- newIORef True return (BufferCodec { encode = utf8_bom_decode ref, recover = recoverDecode cfm, close = return (), getState = readIORef ref, setState = writeIORef ref }) utf8_bom_EF :: CodingFailureMode -> IO (TextEncoder Bool) utf8_bom_EF cfm = do ref <- newIORef True return (BufferCodec { encode = utf8_bom_encode ref, recover = recoverEncode cfm, close = return (), getState = readIORef ref, setState = writeIORef ref }) utf8_bom_decode :: IORef Bool -> DecodeBuffer utf8_bom_decode ref input@Buffer{ bufRaw=iraw, bufL=ir, bufR=iw, bufSize=_ } output = do first <- readIORef ref if not first then utf8_decode input output else do let no_bom = do writeIORef ref False; utf8_decode input output if iw - ir < 1 then return (InputUnderflow,input,output) else do c0 <- readWord8Buf iraw ir if (c0 /= bom0) then no_bom else do if iw - ir < 2 then return (InputUnderflow,input,output) else do c1 <- readWord8Buf iraw (ir+1) if (c1 /= bom1) then no_bom else do if iw - ir < 3 then return (InputUnderflow,input,output) else do c2 <- readWord8Buf iraw (ir+2) if (c2 /= bom2) then no_bom else do -- found a BOM, ignore it and carry on writeIORef ref False utf8_decode input{ bufL = ir + 3 } output utf8_bom_encode :: IORef Bool -> EncodeBuffer utf8_bom_encode ref input output@Buffer{ bufRaw=oraw, bufL=_, bufR=ow, bufSize=os } = do b <- readIORef ref if not b then utf8_encode input output else if os - ow < 3 then return (OutputUnderflow,input,output) else do writeIORef ref False writeWord8Buf oraw ow bom0 writeWord8Buf oraw (ow+1) bom1 writeWord8Buf oraw (ow+2) bom2 utf8_encode input output{ bufR = ow+3 } bom0, bom1, bom2 :: Word8 bom0 = 0xef bom1 = 0xbb bom2 = 0xbf utf8_decode :: DecodeBuffer utf8_decode input@Buffer{ bufRaw=iraw, bufL=ir0, bufR=iw, bufSize=_ } output@Buffer{ bufRaw=oraw, bufL=_, bufR=ow0, bufSize=os } = let loop !ir !ow | ow >= os = done OutputUnderflow ir ow | ir >= iw = done InputUnderflow ir ow | otherwise = do c0 <- readWord8Buf iraw ir case c0 of _ | c0 <= 0x7f -> do ow' <- writeCharBuf oraw ow (unsafeChr (fromIntegral c0)) loop (ir+1) ow' | c0 >= 0xc0 && c0 <= 0xc1 -> invalid -- Overlong forms | c0 >= 0xc2 && c0 <= 0xdf -> if iw - ir < 2 then done InputUnderflow ir ow else do c1 <- readWord8Buf iraw (ir+1) if (c1 < 0x80 || c1 >= 0xc0) then invalid else do ow' <- writeCharBuf oraw ow (chr2 c0 c1) loop (ir+2) ow' | c0 >= 0xe0 && c0 <= 0xef -> case iw - ir of 1 -> done InputUnderflow ir ow 2 -> do -- check for an error even when we don't have -- the full sequence yet (#3341) c1 <- readWord8Buf iraw (ir+1) if not (validate3 c0 c1 0x80) then invalid else done InputUnderflow ir ow _ -> do c1 <- readWord8Buf iraw (ir+1) c2 <- readWord8Buf iraw (ir+2) if not (validate3 c0 c1 c2) then invalid else do ow' <- writeCharBuf oraw ow (chr3 c0 c1 c2) loop (ir+3) ow' | c0 >= 0xf0 -> case iw - ir of 1 -> done InputUnderflow ir ow 2 -> do -- check for an error even when we don't have -- the full sequence yet (#3341) c1 <- readWord8Buf iraw (ir+1) if not (validate4 c0 c1 0x80 0x80) then invalid else done InputUnderflow ir ow 3 -> do c1 <- readWord8Buf iraw (ir+1) c2 <- readWord8Buf iraw (ir+2) if not (validate4 c0 c1 c2 0x80) then invalid else done InputUnderflow ir ow _ -> do c1 <- readWord8Buf iraw (ir+1) c2 <- readWord8Buf iraw (ir+2) c3 <- readWord8Buf iraw (ir+3) if not (validate4 c0 c1 c2 c3) then invalid else do ow' <- writeCharBuf oraw ow (chr4 c0 c1 c2 c3) loop (ir+4) ow' | otherwise -> invalid where invalid = done InvalidSequence ir ow -- lambda-lifted, to avoid thunks being built in the inner-loop: done why !ir !ow = return (why, if ir == iw then input{ bufL=0, bufR=0 } else input{ bufL=ir }, output{ bufR=ow }) in loop ir0 ow0 utf8_encode :: EncodeBuffer utf8_encode input@Buffer{ bufRaw=iraw, bufL=ir0, bufR=iw, bufSize=_ } output@Buffer{ bufRaw=oraw, bufL=_, bufR=ow0, bufSize=os } = let done why !ir !ow = return (why, if ir == iw then input{ bufL=0, bufR=0 } else input{ bufL=ir }, output{ bufR=ow }) loop !ir !ow | ow >= os = done OutputUnderflow ir ow | ir >= iw = done InputUnderflow ir ow | otherwise = do (c,ir') <- readCharBuf iraw ir case ord c of x | x <= 0x7F -> do writeWord8Buf oraw ow (fromIntegral x) loop ir' (ow+1) | x <= 0x07FF -> if os - ow < 2 then done OutputUnderflow ir ow else do let (c1,c2) = ord2 c writeWord8Buf oraw ow c1 writeWord8Buf oraw (ow+1) c2 loop ir' (ow+2) | x <= 0xFFFF -> if isSurrogate c then done InvalidSequence ir ow else do if os - ow < 3 then done OutputUnderflow ir ow else do let (c1,c2,c3) = ord3 c writeWord8Buf oraw ow c1 writeWord8Buf oraw (ow+1) c2 writeWord8Buf oraw (ow+2) c3 loop ir' (ow+3) | otherwise -> do if os - ow < 4 then done OutputUnderflow ir ow else do let (c1,c2,c3,c4) = ord4 c writeWord8Buf oraw ow c1 writeWord8Buf oraw (ow+1) c2 writeWord8Buf oraw (ow+2) c3 writeWord8Buf oraw (ow+3) c4 loop ir' (ow+4) in loop ir0 ow0 -- ----------------------------------------------------------------------------- -- UTF-8 primitives, lifted from Data.Text.Fusion.Utf8 ord2 :: Char -> (Word8,Word8) ord2 c = assert (n >= 0x80 && n <= 0x07ff) (x1,x2) where n = ord c x1 = fromIntegral $ (n `shiftR` 6) + 0xC0 x2 = fromIntegral $ (n .&. 0x3F) + 0x80 ord3 :: Char -> (Word8,Word8,Word8) ord3 c = assert (n >= 0x0800 && n <= 0xffff) (x1,x2,x3) where n = ord c x1 = fromIntegral $ (n `shiftR` 12) + 0xE0 x2 = fromIntegral $ ((n `shiftR` 6) .&. 0x3F) + 0x80 x3 = fromIntegral $ (n .&. 0x3F) + 0x80 ord4 :: Char -> (Word8,Word8,Word8,Word8) ord4 c = assert (n >= 0x10000) (x1,x2,x3,x4) where n = ord c x1 = fromIntegral $ (n `shiftR` 18) + 0xF0 x2 = fromIntegral $ ((n `shiftR` 12) .&. 0x3F) + 0x80 x3 = fromIntegral $ ((n `shiftR` 6) .&. 0x3F) + 0x80 x4 = fromIntegral $ (n .&. 0x3F) + 0x80 chr2 :: Word8 -> Word8 -> Char chr2 (W8# x1#) (W8# x2#) = C# (chr# (z1# +# z2#)) where !y1# = word2Int# (word8ToWord# x1#) !y2# = word2Int# (word8ToWord# x2#) !z1# = uncheckedIShiftL# (y1# -# 0xC0#) 6# !z2# = y2# -# 0x80# {-# INLINE chr2 #-} chr3 :: Word8 -> Word8 -> Word8 -> Char chr3 (W8# x1#) (W8# x2#) (W8# x3#) = C# (chr# (z1# +# z2# +# z3#)) where !y1# = word2Int# (word8ToWord# x1#) !y2# = word2Int# (word8ToWord# x2#) !y3# = word2Int# (word8ToWord# x3#) !z1# = uncheckedIShiftL# (y1# -# 0xE0#) 12# !z2# = uncheckedIShiftL# (y2# -# 0x80#) 6# !z3# = y3# -# 0x80# {-# INLINE chr3 #-} chr4 :: Word8 -> Word8 -> Word8 -> Word8 -> Char chr4 (W8# x1#) (W8# x2#) (W8# x3#) (W8# x4#) = C# (chr# (z1# +# z2# +# z3# +# z4#)) where !y1# = word2Int# (word8ToWord# x1#) !y2# = word2Int# (word8ToWord# x2#) !y3# = word2Int# (word8ToWord# x3#) !y4# = word2Int# (word8ToWord# x4#) !z1# = uncheckedIShiftL# (y1# -# 0xF0#) 18# !z2# = uncheckedIShiftL# (y2# -# 0x80#) 12# !z3# = uncheckedIShiftL# (y3# -# 0x80#) 6# !z4# = y4# -# 0x80# {-# INLINE chr4 #-} between :: Word8 -- ^ byte to check -> Word8 -- ^ lower bound -> Word8 -- ^ upper bound -> Bool between x y z = x >= y && x <= z {-# INLINE between #-} validate3 :: Word8 -> Word8 -> Word8 -> Bool {-# INLINE validate3 #-} validate3 x1 x2 x3 = validate3_1 || validate3_2 || validate3_3 || validate3_4 where validate3_1 = (x1 == 0xE0) && between x2 0xA0 0xBF && between x3 0x80 0xBF validate3_2 = between x1 0xE1 0xEC && between x2 0x80 0xBF && between x3 0x80 0xBF validate3_3 = x1 == 0xED && between x2 0x80 0x9F && between x3 0x80 0xBF validate3_4 = between x1 0xEE 0xEF && between x2 0x80 0xBF && between x3 0x80 0xBF validate4 :: Word8 -> Word8 -> Word8 -> Word8 -> Bool {-# INLINE validate4 #-} validate4 x1 x2 x3 x4 = validate4_1 || validate4_2 || validate4_3 where validate4_1 = x1 == 0xF0 && between x2 0x90 0xBF && between x3 0x80 0xBF && between x4 0x80 0xBF validate4_2 = between x1 0xF1 0xF3 && between x2 0x80 0xBF && between x3 0x80 0xBF && between x4 0x80 0xBF validate4_3 = x1 == 0xF4 && between x2 0x80 0x8F && between x3 0x80 0xBF && between x4 0x80 0xBF