-{-# OPTIONS_GHC -fno-implicit-prelude -funbox-strict-fields #-}
-{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE NoImplicitPrelude
+ , BangPatterns
+ , NondecreasingIndentation
+ , MagicHash
+ #-}
+{-# OPTIONS_GHC -funbox-strict-fields #-}
+
-----------------------------------------------------------------------------
-- |
-- Module : GHC.IO.Encoding.UTF8
-----------------------------------------------------------------------------
module GHC.IO.Encoding.UTF8 (
- utf8,
- utf8_decode,
- utf8_encode,
+ 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.Exception
import GHC.IO.Buffer
+import GHC.IO.Encoding.Failure
import GHC.IO.Encoding.Types
import GHC.Word
import Data.Bits
-import Data.Maybe
utf8 :: TextEncoding
-utf8 = TextEncoding { mkTextDecoder = utf8_DF,
- mkTextEncoder = utf8_EF }
+utf8 = mkUTF8 ErrorOnCodingFailure
+
+mkUTF8 :: CodingFailureMode -> TextEncoding
+mkUTF8 cfm = TextEncoding { textEncodingName = "UTF-8",
+ mkTextDecoder = utf8_DF cfm,
+ mkTextEncoder = utf8_EF cfm }
+
-utf8_DF :: IO (TextDecoder ())
-utf8_DF =
+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 :: IO (TextEncoder ())
-utf8_EF =
+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 || ir >= iw = done ir ow
+ | ow >= os = done OutputUnderflow ir ow
+ | ir >= iw = done InputUnderflow ir ow
| otherwise = do
c0 <- readWord8Buf iraw ir
case c0 of
ow' <- writeCharBuf oraw ow (unsafeChr (fromIntegral c0))
loop (ir+1) ow'
| c0 >= 0xc0 && c0 <= 0xdf ->
- if iw - ir < 2 then done ir ow else do
+ 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 ->
- if iw - ir < 3 then done ir ow else do
+ 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 ->
- if iw - ir < 4 then done ir ow else do
+ 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)
| otherwise ->
invalid
where
- invalid = if ir > ir0 then done ir ow else ioe_decodingError
+ invalid = done InvalidSequence ir ow
-- lambda-lifted, to avoid thunks being built in the inner-loop:
- done !ir !ow = return (if ir == iw then input{ bufL=0, bufR=0 }
- else input{ bufL=ir },
- output{ bufR=ow })
+ 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
-ioe_decodingError :: IO a
-ioe_decodingError = ioException
- (IOError Nothing InvalidArgument "utf8_decode"
- "invalid UTF-8 byte sequence" Nothing Nothing)
-
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 !ir !ow = return (if ir == iw then input{ bufL=0, bufR=0 }
- else input{ bufL=ir },
- output{ bufR=ow })
+ 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 || ir >= iw = done 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
writeWord8Buf oraw ow (fromIntegral x)
loop ir' (ow+1)
| x <= 0x07FF ->
- if os - ow < 2 then done ir ow else do
+ 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 -> do
- if os - ow < 3 then done ir ow else do
+ | 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 ir ow else 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
projects / ghc-base.git / blobdiff