diff options
Diffstat (limited to 'Utility/FileSystemEncoding.hs')
| -rw-r--r-- | Utility/FileSystemEncoding.hs | 159 |
1 files changed, 126 insertions, 33 deletions
diff --git a/Utility/FileSystemEncoding.hs b/Utility/FileSystemEncoding.hs index 67341d3..f9e9814 100644 --- a/Utility/FileSystemEncoding.hs +++ b/Utility/FileSystemEncoding.hs @@ -1,6 +1,6 @@ {- GHC File system encoding handling. - - - Copyright 2012-2014 Joey Hess <id@joeyh.name> + - Copyright 2012-2016 Joey Hess <id@joeyh.name> - - License: BSD-2-clause -} @@ -9,16 +9,25 @@ {-# OPTIONS_GHC -fno-warn-tabs #-} module Utility.FileSystemEncoding ( + useFileSystemEncoding, fileEncoding, withFilePath, - md5FilePath, + RawFilePath, + fromRawFilePath, + toRawFilePath, + decodeBL, + encodeBL, decodeBS, encodeBS, - decodeW8, - encodeW8, - encodeW8NUL, - decodeW8NUL, + decodeBL', + encodeBL', + decodeBS', + encodeBS', truncateFilePath, + s2w8, + w82s, + c2w8, + w82c, ) where import qualified GHC.Foreign as GHC @@ -26,29 +35,47 @@ import qualified GHC.IO.Encoding as Encoding import Foreign.C import System.IO import System.IO.Unsafe -import qualified Data.Hash.MD5 as MD5 import Data.Word -import Data.Bits.Utils import Data.List -import Data.List.Utils +import qualified Data.ByteString as S import qualified Data.ByteString.Lazy as L #ifdef mingw32_HOST_OS +import qualified Data.ByteString.UTF8 as S8 import qualified Data.ByteString.Lazy.UTF8 as L8 #endif import Utility.Exception +import Utility.Split -{- Sets a Handle to use the filesystem encoding. This causes data - - written or read from it to be encoded/decoded the same - - as ghc 7.4 does to filenames etc. This special encoding - - allows "arbitrary undecodable bytes to be round-tripped through it". +{- Makes all subsequent Handles that are opened, as well as stdio Handles, + - use the filesystem encoding, instead of the encoding of the current + - locale. + - + - The filesystem encoding allows "arbitrary undecodable bytes to be + - round-tripped through it". This avoids encoded failures when data is not + - encoded matching the current locale. + - + - Note that code can still use hSetEncoding to change the encoding of a + - Handle. This only affects the default encoding. -} +useFileSystemEncoding :: IO () +useFileSystemEncoding = do +#ifndef mingw32_HOST_OS + e <- Encoding.getFileSystemEncoding +#else + {- The file system encoding does not work well on Windows, + - and Windows only has utf FilePaths anyway. -} + let e = Encoding.utf8 +#endif + hSetEncoding stdin e + hSetEncoding stdout e + hSetEncoding stderr e + Encoding.setLocaleEncoding e + fileEncoding :: Handle -> IO () #ifndef mingw32_HOST_OS fileEncoding h = hSetEncoding h =<< Encoding.getFileSystemEncoding #else -{- The file system encoding does not work well on Windows, - - and Windows only has utf FilePaths anyway. -} fileEncoding h = hSetEncoding h Encoding.utf8 #endif @@ -82,36 +109,92 @@ _encodeFilePath fp = unsafePerformIO $ do GHC.withCString enc fp (GHC.peekCString Encoding.char8) `catchNonAsync` (\_ -> return fp) -{- Encodes a FilePath into a Md5.Str, applying the filesystem encoding. -} -md5FilePath :: FilePath -> MD5.Str -md5FilePath = MD5.Str . _encodeFilePath - {- Decodes a ByteString into a FilePath, applying the filesystem encoding. -} -decodeBS :: L.ByteString -> FilePath +decodeBL :: L.ByteString -> FilePath #ifndef mingw32_HOST_OS -decodeBS = encodeW8NUL . L.unpack +decodeBL = encodeW8NUL . L.unpack #else {- On Windows, we assume that the ByteString is utf-8, since Windows - only uses unicode for filenames. -} -decodeBS = L8.toString +decodeBL = L8.toString #endif {- Encodes a FilePath into a ByteString, applying the filesystem encoding. -} -encodeBS :: FilePath -> L.ByteString +encodeBL :: FilePath -> L.ByteString +#ifndef mingw32_HOST_OS +encodeBL = L.pack . decodeW8NUL +#else +encodeBL = L8.fromString +#endif + +decodeBS :: S.ByteString -> FilePath +#ifndef mingw32_HOST_OS +decodeBS = encodeW8NUL . S.unpack +#else +decodeBS = S8.toString +#endif + +encodeBS :: FilePath -> S.ByteString +#ifndef mingw32_HOST_OS +encodeBS = S.pack . decodeW8NUL +#else +encodeBS = S8.fromString +#endif + +{- Faster version that assumes the string does not contain NUL; + - if it does it will be truncated before the NUL. -} +decodeBS' :: S.ByteString -> FilePath #ifndef mingw32_HOST_OS -encodeBS = L.pack . decodeW8NUL +decodeBS' = encodeW8 . S.unpack #else -encodeBS = L8.fromString +decodeBS' = S8.toString #endif +encodeBS' :: FilePath -> S.ByteString +#ifndef mingw32_HOST_OS +encodeBS' = S.pack . decodeW8 +#else +encodeBS' = S8.fromString +#endif + +decodeBL' :: L.ByteString -> FilePath +#ifndef mingw32_HOST_OS +decodeBL' = encodeW8 . L.unpack +#else +decodeBL' = L8.toString +#endif + +encodeBL' :: FilePath -> L.ByteString +#ifndef mingw32_HOST_OS +encodeBL' = L.pack . decodeW8 +#else +encodeBL' = L8.fromString +#endif + +{- Recent versions of the unix package have this alias; defined here + - for backwards compatibility. -} +type RawFilePath = S.ByteString + +{- Note that the RawFilePath is assumed to never contain NUL, + - since filename's don't. This should only be used with actual + - RawFilePaths not arbitrary ByteString that may contain NUL. -} +fromRawFilePath :: RawFilePath -> FilePath +fromRawFilePath = decodeBS' + +{- Note that the FilePath is assumed to never contain NUL, + - since filename's don't. This should only be used with actual FilePaths + - not arbitrary String that may contain NUL. -} +toRawFilePath :: FilePath -> RawFilePath +toRawFilePath = encodeBS' + {- Converts a [Word8] to a FilePath, encoding using the filesystem encoding. - - - w82c produces a String, which may contain Chars that are invalid + - w82s produces a String, which may contain Chars that are invalid - unicode. From there, this is really a simple matter of applying the - file system encoding, only complicated by GHC's interface to doing so. - - Note that the encoding stops at any NUL in the input. FilePaths - - do not normally contain embedded NUL, but Haskell Strings may. + - cannot contain embedded NUL, but Haskell Strings may. -} {-# NOINLINE encodeW8 #-} encodeW8 :: [Word8] -> FilePath @@ -119,21 +202,31 @@ encodeW8 w8 = unsafePerformIO $ do enc <- Encoding.getFileSystemEncoding GHC.withCString Encoding.char8 (w82s w8) $ GHC.peekCString enc -{- Useful when you want the actual number of bytes that will be used to - - represent the FilePath on disk. -} decodeW8 :: FilePath -> [Word8] decodeW8 = s2w8 . _encodeFilePath {- Like encodeW8 and decodeW8, but NULs are passed through unchanged. -} encodeW8NUL :: [Word8] -> FilePath -encodeW8NUL = intercalate nul . map encodeW8 . split (s2w8 nul) +encodeW8NUL = intercalate [nul] . map encodeW8 . splitc (c2w8 nul) where - nul = ['\NUL'] + nul = '\NUL' decodeW8NUL :: FilePath -> [Word8] -decodeW8NUL = intercalate (s2w8 nul) . map decodeW8 . split nul +decodeW8NUL = intercalate [c2w8 nul] . map decodeW8 . splitc nul where - nul = ['\NUL'] + nul = '\NUL' + +c2w8 :: Char -> Word8 +c2w8 = fromIntegral . fromEnum + +w82c :: Word8 -> Char +w82c = toEnum . fromIntegral + +s2w8 :: String -> [Word8] +s2w8 = map c2w8 + +w82s :: [Word8] -> String +w82s = map w82c {- Truncates a FilePath to the given number of bytes (or less), - as represented on disk. |