{-# LANGUAGE CPP #-} {-# LANGUAGE ForeignFunctionInterface #-} -- | -- Module: Filesystem -- Copyright: 2011-2012 John Millikin -- License: MIT -- -- Maintainer: John Millikin -- Portability: portable -- -- Simple 'FilePath'‐aware wrappers around standard "System.IO" -- computations. These wrappers are designed to work as similarly as -- possible across various versions of GHC. -- -- In particular, they do not require POSIX file paths to be valid strings, -- and can therefore open paths regardless of the current locale encoding. module Filesystem ( -- * Exports from System.IO IO.Handle , IO.IOMode(..) -- * Files , isFile , getModified , getSize , copyFile , copyFileContent , copyPermissions , removeFile -- ** Binary files , openFile , withFile , readFile , writeFile , appendFile -- ** Text files , openTextFile , withTextFile , readTextFile , writeTextFile , appendTextFile -- * Directories , isDirectory , canonicalizePath , listDirectory -- ** Creating directories , createDirectory , createTree -- ** Removing directories , removeDirectory , removeTree -- ** Current working directory , getWorkingDirectory , setWorkingDirectory -- ** Commonly used paths , getHomeDirectory , getDesktopDirectory , getDocumentsDirectory , getAppDataDirectory , getAppCacheDirectory , getAppConfigDirectory -- * Other , rename ) where import Prelude hiding (FilePath, readFile, writeFile, appendFile) import qualified Control.Exception as Exc import Control.Monad (forM_, unless, when) import qualified Data.ByteString as B import qualified Data.ByteString.Lazy as BL import qualified Data.Text as T import qualified Data.Text.IO as T import Foreign.Ptr (Ptr, nullPtr) import Foreign.C (CInt(..), CString, withCAString) import qualified Foreign.C.Error as CError import qualified System.Environment as SE import Filesystem.Path (FilePath, append) import qualified Filesystem.Path as Path import Filesystem.Path.CurrentOS (currentOS, encodeString, decodeString) import qualified Filesystem.Path.Rules as R import qualified System.IO as IO import System.IO.Error (IOError) #ifdef CABAL_OS_WINDOWS import Data.Bits ((.|.)) import Data.Time ( UTCTime(..) , fromGregorian , secondsToDiffTime , picosecondsToDiffTime) import Foreign.C (CWString, withCWString) import qualified System.Win32 as Win32 import System.IO.Error (isDoesNotExistError) import qualified System.Directory as SD #else import Data.Time (UTCTime) import Data.Time.Clock.POSIX (posixSecondsToUTCTime) import qualified System.Posix as Posix import qualified System.Posix.Error as Posix #if MIN_VERSION_unix(2,5,1) import qualified System.Posix.Files.ByteString #endif #endif #ifdef SYSTEMFILEIO_LOCAL_OPEN_FILE import Data.Bits ((.|.)) import GHC.IO.Handle.FD (mkHandleFromFD) import GHC.IO.FD (mkFD) import qualified GHC.IO.Device import qualified System.Posix.Internals #endif -- | Check if a file exists at the given path. -- -- Any non‐directory object, including devices and pipes, are -- considered to be files. Symbolic links are resolved to their targets -- before checking their type. -- -- This computation does not throw exceptions. isFile :: FilePath -> IO Bool #ifdef CABAL_OS_WINDOWS isFile path = SD.doesFileExist (encodeString path) #else isFile path = Exc.catch (do stat <- posixStat "isFile" path return (not (Posix.isDirectory stat))) ((\_ -> return False) :: IOError -> IO Bool) #endif -- | Check if a directory exists at the given path. -- -- Symbolic links are resolved to their targets before checking their type. -- -- This computation does not throw exceptions. isDirectory :: FilePath -> IO Bool #ifdef CABAL_OS_WINDOWS isDirectory path = SD.doesDirectoryExist (encodeString path) #else isDirectory path = Exc.catch (do stat <- posixStat "isDirectory" path return (Posix.isDirectory stat)) ((\_ -> return False) :: IOError -> IO Bool) #endif -- | Rename a filesystem object. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. rename :: FilePath -> FilePath -> IO () rename old new = #ifdef CABAL_OS_WINDOWS let old' = encodeString old in let new' = encodeString new in #if MIN_VERSION_Win32(2,6,0) Win32.moveFileEx old' (Just new') Win32.mOVEFILE_REPLACE_EXISTING #else Win32.moveFileEx old' new' Win32.mOVEFILE_REPLACE_EXISTING #endif #else withFilePath old $ \old' -> withFilePath new $ \new' -> throwErrnoPathIfMinus1_ "rename" old (c_rename old' new') foreign import ccall unsafe "rename" c_rename :: CString -> CString -> IO CInt #endif -- | Resolve symlinks and \"..\" path elements to return a canonical path. -- It is intended that two paths referring to the same object will always -- resolve to the same canonical path. -- -- Note that on many operating systems, it is impossible to guarantee that -- two paths to the same file will resolve to the same canonical path. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. -- -- Since: 0.1.1 canonicalizePath :: FilePath -> IO FilePath canonicalizePath path = fmap (preserveFinalSlash path) $ let path' = encodeString path in #ifdef CABAL_OS_WINDOWS fmap decodeString $ #if MIN_VERSION_Win32(2,2,1) Win32.getFullPathName path' #else Win32.withTString path' $ \c_name -> do Win32.try "getFullPathName" (\buf len -> c_GetFullPathNameW c_name len buf nullPtr) 512 #endif #else withFilePath path $ \cPath -> do cOut <- Posix.throwErrnoPathIfNull "canonicalizePath" path' (c_realpath cPath nullPtr) bytes <- B.packCString cOut c_free cOut return (R.decode R.posix bytes) #endif preserveFinalSlash :: FilePath -> FilePath -> FilePath preserveFinalSlash orig out = if Path.null (Path.filename orig) then Path.append out Path.empty else out #ifdef CABAL_OS_WINDOWS #if MIN_VERSION_Win32(2,2,1) #else foreign import stdcall unsafe "GetFullPathNameW" c_GetFullPathNameW :: Win32.LPCTSTR -> Win32.DWORD -> Win32.LPTSTR -> Ptr Win32.LPTSTR -> IO Win32.DWORD #endif #endif #ifndef CABAL_OS_WINDOWS foreign import ccall unsafe "realpath" c_realpath :: CString -> CString -> IO CString #endif -- | Create a directory at a given path. The user may choose whether it is -- an error for a directory to already exist at that path. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. createDirectory :: Bool -- ^ Succeed if the directory already exists -> FilePath -> IO () createDirectory succeedIfExists path = #ifdef CABAL_OS_WINDOWS let path' = encodeString path in if succeedIfExists then SD.createDirectoryIfMissing False path' else Win32.createDirectory path' Nothing #else withFilePath path $ \cPath -> throwErrnoPathIfMinus1Retry_ "createDirectory" path $ if succeedIfExists then mkdirIfMissing path cPath 0o777 else c_mkdir cPath 0o777 mkdirIfMissing :: FilePath -> CString -> CInt -> IO CInt mkdirIfMissing path cPath mode = do rc <- c_mkdir cPath mode if rc == -1 then do errno <- CError.getErrno if errno == CError.eEXIST then do dirExists <- isDirectory path if dirExists then return 0 else return rc else return rc else return rc foreign import ccall unsafe "mkdir" c_mkdir :: CString -> CInt -> IO CInt #endif -- | Create a directory at a given path, including any parents which might -- be missing. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. createTree :: FilePath -> IO () #ifdef CABAL_OS_WINDOWS createTree path = SD.createDirectoryIfMissing True (encodeString path) #else createTree path = do let parent = Path.parent path parentExists <- isDirectory parent unless parentExists (createTree parent) withFilePath path $ \cPath -> throwErrnoPathIfMinus1Retry_ "createTree" path (mkdirIfMissing path cPath 0o777) #endif -- | List objects in a directory, excluding @\".\"@ and @\"..\"@. Each -- returned 'FilePath' includes the path of the directory. Entries are not -- sorted. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. listDirectory :: FilePath -> IO [FilePath] #ifdef CABAL_OS_WINDOWS listDirectory root = fmap cleanup contents where contents = SD.getDirectoryContents (encodeString root) cleanup = map (append root) . map decodeString . filter (`notElem` [".", ".."]) #else listDirectory root = Exc.bracket alloc free list where alloc = do dir <- openDir root let Dir _ dirp = dir dirent <- c_alloc_dirent dirp return (dirent, dir) free (dirent, dir) = do c_free_dirent dirent closeDir dir list (dirent, dir) = loop where loop = do next <- readDir dir dirent case next of Nothing -> return [] Just bytes | ignore bytes -> loop Just bytes -> do let name = append root (R.decode R.posix bytes) names <- loop return (name:names) ignore :: B.ByteString -> Bool ignore = ignore' where dot = B.pack [46] dotdot = B.pack [46, 46] ignore' b = b == dot || b == dotdot data Dir = Dir FilePath (Ptr ()) openDir :: FilePath -> IO Dir openDir root = withFilePath root $ \cRoot -> do p <- throwErrnoPathIfNullRetry "listDirectory" root (c_opendir cRoot) return (Dir root p) closeDir :: Dir -> IO () closeDir (Dir _ p) = CError.throwErrnoIfMinus1Retry_ "listDirectory" (c_closedir p) readDir :: Dir -> Ptr () -> IO (Maybe B.ByteString) readDir (Dir _ p) dirent = do rc <- CError.throwErrnoIfMinus1Retry "listDirectory" (c_readdir p dirent) if rc == 0 then do bytes <- c_dirent_name dirent >>= B.packCString return (Just bytes) else return Nothing foreign import ccall unsafe "opendir" c_opendir :: CString -> IO (Ptr ()) foreign import ccall unsafe "closedir" c_closedir :: Ptr () -> IO CInt foreign import ccall unsafe "hssystemfileio_alloc_dirent" c_alloc_dirent :: Ptr () -> IO (Ptr ()) foreign import ccall unsafe "hssystemfileio_free_dirent" c_free_dirent :: Ptr () -> IO () foreign import ccall unsafe "hssystemfileio_readdir" c_readdir :: Ptr () -> Ptr () -> IO CInt foreign import ccall unsafe "hssystemfileio_dirent_name" c_dirent_name :: Ptr () -> IO CString #endif -- | Remove a file. This will fail if the file does not exist. -- -- This computation cannot remove directories. For that, use 'removeDirectory' -- or 'removeTree'. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. removeFile :: FilePath -> IO () removeFile path = #ifdef CABAL_OS_WINDOWS Win32.deleteFile (encodeString path) #else withFilePath path $ \cPath -> throwErrnoPathIfMinus1_ "removeFile" path (c_unlink cPath) foreign import ccall unsafe "unlink" c_unlink :: CString -> IO CInt #endif -- | Remove an empty directory. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. removeDirectory :: FilePath -> IO () removeDirectory path = #ifdef CABAL_OS_WINDOWS Win32.removeDirectory (encodeString path) #else withFilePath path $ \cPath -> throwErrnoPathIfMinus1Retry_ "removeDirectory" path (c_rmdir cPath) foreign import ccall unsafe "rmdir" c_rmdir :: CString -> IO CInt #endif -- | Recursively remove a directory tree rooted at the given path. -- -- This computation does not follow symlinks. If the tree contains symlinks, -- the links themselves will be removed, but not the objects they point to. -- -- If the root path is a symlink, then it will be treated as if it were a -- regular directory. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. removeTree :: FilePath -> IO () #ifdef CABAL_OS_WINDOWS removeTree root = SD.removeDirectoryRecursive (encodeString root) #else removeTree root = do items <- listDirectory root forM_ items $ \item -> Exc.catch (removeFile item) (\exc -> do isDir <- isRealDir item if isDir then removeTree item else Exc.throwIO (exc :: IOError)) removeDirectory root -- Check whether a path is a directory, and not just a symlink to a directory. -- -- This is used in 'removeTree' to prevent recursing into symlinks if the link -- itself cannot be deleted. isRealDir :: FilePath -> IO Bool isRealDir path = withFilePath path $ \cPath -> do rc <- throwErrnoPathIfMinus1Retry "removeTree" path (c_isrealdir cPath) return (rc == 1) foreign import ccall unsafe "hssystemfileio_isrealdir" c_isrealdir :: CString -> IO CInt #endif -- | Get the current working directory. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getWorkingDirectory :: IO FilePath getWorkingDirectory = do #ifdef CABAL_OS_WINDOWS #if MIN_VERSION_Win32(2,2,1) fmap decodeString Win32.getCurrentDirectory #else fmap decodeString (Win32.try "getWorkingDirectory" (flip c_GetCurrentDirectoryW) 512) #endif #else buf <- CError.throwErrnoIfNull "getWorkingDirectory" c_getcwd bytes <- B.packCString buf c_free buf return (R.decode R.posix bytes) foreign import ccall unsafe "hssystemfileio_getcwd" c_getcwd :: IO CString #endif #ifdef CABAL_OS_WINDOWS #if MIN_VERSION_Win32(2,2,1) #else foreign import stdcall unsafe "GetCurrentDirectoryW" c_GetCurrentDirectoryW :: Win32.DWORD -> Win32.LPTSTR -> IO Win32.UINT #endif #endif -- | Set the current working directory. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. setWorkingDirectory :: FilePath -> IO () setWorkingDirectory path = #ifdef CABAL_OS_WINDOWS Win32.setCurrentDirectory (encodeString path) #else withFilePath path $ \cPath -> throwErrnoPathIfMinus1Retry_ "setWorkingDirectory" path (c_chdir cPath) foreign import ccall unsafe "chdir" c_chdir :: CString -> IO CInt #endif -- TODO: expose all known exceptions as specific types, for users to catch -- if need be -- | Get the user’s home directory. This is useful for building paths -- to more specific directories. -- -- For directing the user to open or safe a document, use -- 'getDocumentsDirectory'. -- -- For data files the user does not explicitly create, such as automatic -- saves, use 'getAppDataDirectory'. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getHomeDirectory :: IO FilePath #ifdef CABAL_OS_WINDOWS getHomeDirectory = fmap decodeString SD.getHomeDirectory #else getHomeDirectory = do path <- getenv "HOME" case path of Just p -> return p Nothing -> do -- use getEnv to throw the right exception type fmap decodeString (SE.getEnv "HOME") #endif -- | Get the user’s desktop directory. This is a good starting point for -- file dialogs and other user queries. For data files the user does not -- explicitly create, such as automatic saves, use 'getAppDataDirectory'. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getDesktopDirectory :: IO FilePath getDesktopDirectory = xdg "XDG_DESKTOP_DIR" Nothing (homeSlash "Desktop") -- | Get the user’s documents directory. This is a good place to save -- user‐created files. For data files the user does not explicitly -- create, such as automatic saves, use 'getAppDataDirectory'. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getDocumentsDirectory :: IO FilePath getDocumentsDirectory = xdg "XDG_DOCUMENTS_DIR" Nothing #ifdef CABAL_OS_WINDOWS (fmap decodeString SD.getUserDocumentsDirectory) #else (homeSlash "Documents") #endif -- | Get the user’s application data directory, given an application -- label. This directory is where applications should store data the user did -- not explicitly create, such as databases and automatic saves. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getAppDataDirectory :: T.Text -> IO FilePath getAppDataDirectory label = xdg "XDG_DATA_HOME" (Just label) #ifdef CABAL_OS_WINDOWS (fmap decodeString (SD.getAppUserDataDirectory "")) #else (homeSlash ".local/share") #endif -- | Get the user’s application cache directory, given an application -- label. This directory is where applications should store caches, which -- might be large and can be safely deleted. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getAppCacheDirectory :: T.Text -> IO FilePath getAppCacheDirectory label = xdg "XDG_CACHE_HOME" (Just label) #ifdef CABAL_OS_WINDOWS (homeSlash "Local Settings\\Cache") #else (homeSlash ".cache") #endif -- | Get the user’s application configuration directory, given an -- application label. This directory is where applications should store their -- configurations and settings. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. getAppConfigDirectory :: T.Text -> IO FilePath getAppConfigDirectory label = xdg "XDG_CONFIG_HOME" (Just label) #ifdef CABAL_OS_WINDOWS (homeSlash "Local Settings") #else (homeSlash ".config") #endif homeSlash :: String -> IO FilePath homeSlash path = do home <- getHomeDirectory return (append home (decodeString path)) getenv :: String -> IO (Maybe FilePath) #ifdef CABAL_OS_WINDOWS getenv key = Exc.catch (fmap (Just . decodeString) (SE.getEnv key)) (\e -> if isDoesNotExistError e then return Nothing else Exc.throwIO e) #else getenv key = withCAString key $ \cKey -> do ret <- c_getenv cKey if ret == nullPtr then return Nothing else do bytes <- B.packCString ret return (Just (R.decode R.posix bytes)) foreign import ccall unsafe "getenv" c_getenv :: CString -> IO CString #endif xdg :: String -> Maybe T.Text -> IO FilePath -> IO FilePath xdg envkey label fallback = do env <- getenv envkey dir <- case env of Just var -> return var Nothing -> fallback return $ case label of Just text -> append dir (R.fromText currentOS text) Nothing -> dir -- | Copy the content of a file to a new entry in the filesystem. If a -- file already exists at the new location, it will be replaced. Copying -- a file is not atomic. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. -- -- Since: 0.2.4 / 0.3.4 copyFileContent :: FilePath -- ^ Old location -> FilePath -- ^ New location -> IO () copyFileContent oldPath newPath = withFile oldPath IO.ReadMode $ \old -> withFile newPath IO.WriteMode $ \new -> BL.hGetContents old >>= BL.hPut new -- | Copy the permissions from one path to another. Both paths must already -- exist. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. -- -- Since: 0.2.4 / 0.3.4 copyPermissions :: FilePath -- ^ Old location -> FilePath -- ^ New location -> IO () copyPermissions oldPath newPath = withFilePath oldPath $ \cOldPath -> withFilePath newPath $ \cNewPath -> CError.throwErrnoIfMinus1Retry_ "copyPermissions" $ c_copy_permissions cOldPath cNewPath #ifdef CABAL_OS_WINDOWS foreign import ccall unsafe "hssystemfileio_copy_permissions" c_copy_permissions :: CWString -> CWString -> IO CInt #else foreign import ccall unsafe "hssystemfileio_copy_permissions" c_copy_permissions :: CString -> CString -> IO CInt #endif -- | Copy the content and permissions of a file to a new entry in the -- filesystem. If a file already exists at the new location, it will be -- replaced. Copying a file is not atomic. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. -- -- Since: 0.1.1 copyFile :: FilePath -- ^ Old location -> FilePath -- ^ New location -> IO () copyFile oldPath newPath = do copyFileContent oldPath newPath Exc.catch (copyPermissions oldPath newPath) ((\_ -> return ()) :: IOError -> IO ()) -- | Get when the object at a given path was last modified. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. -- -- Since: 0.2 getModified :: FilePath -> IO UTCTime getModified path = do #ifdef CABAL_OS_WINDOWS info <- withHANDLE path Win32.getFileInformationByHandle let ftime = Win32.bhfiLastWriteTime info stime <- Win32.fileTimeToSystemTime ftime let date = fromGregorian (fromIntegral (Win32.wYear stime)) (fromIntegral (Win32.wMonth stime)) (fromIntegral (Win32.wDay stime)) seconds = secondsToDiffTime $ (toInteger (Win32.wHour stime) * 3600) + (toInteger (Win32.wMinute stime) * 60) + (toInteger (Win32.wSecond stime)) msecs = picosecondsToDiffTime $ (toInteger (Win32.wMilliseconds stime) * 1000000000) return (UTCTime date (seconds + msecs)) #else stat <- posixStat "getModified" path let mtime = Posix.modificationTime stat return (posixSecondsToUTCTime (realToFrac mtime)) #endif -- | Get the size of an object at a given path. For special objects like -- links or directories, the size is filesystem‐ and -- platform‐dependent. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. -- -- Since: 0.2 getSize :: FilePath -> IO Integer getSize path = do #ifdef CABAL_OS_WINDOWS info <- withHANDLE path Win32.getFileInformationByHandle return (toInteger (Win32.bhfiSize info)) #else stat <- posixStat "getSize" path return (toInteger (Posix.fileSize stat)) #endif -- | Open a file in binary mode, and return an open 'Handle'. The 'Handle' -- should be closed with 'IO.hClose' when it is no longer needed. -- -- 'withFile' is easier to use, because it will handle the 'Handle'’s -- lifetime automatically. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. openFile :: FilePath -> IO.IOMode -> IO IO.Handle #ifdef SYSTEMFILEIO_LOCAL_OPEN_FILE openFile path mode = openFile' "openFile" path mode Nothing #else openFile path = IO.openBinaryFile (encodeString path) #endif -- | Open a file in binary mode, and pass its 'Handle' to a provided -- computation. The 'Handle' will be automatically closed when the -- computation returns. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. withFile :: FilePath -> IO.IOMode -> (IO.Handle -> IO a) -> IO a withFile path mode = Exc.bracket (openFile path mode) IO.hClose -- | Read in the entire content of a binary file. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. readFile :: FilePath -> IO B.ByteString readFile path = withFile path IO.ReadMode (\h -> IO.hFileSize h >>= B.hGet h . fromIntegral) -- | Replace the entire content of a binary file with the provided -- 'B.ByteString'. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. writeFile :: FilePath -> B.ByteString -> IO () writeFile path bytes = withFile path IO.WriteMode (\h -> B.hPut h bytes) -- | Append a 'B.ByteString' to a file. If the file does not exist, it will -- be created. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. appendFile :: FilePath -> B.ByteString -> IO () appendFile path bytes = withFile path IO.AppendMode (\h -> B.hPut h bytes) -- | Open a file in text mode, and return an open 'Handle'. The 'Handle' -- should be closed with 'IO.hClose' when it is no longer needed. -- -- 'withTextFile' is easier to use, because it will handle the -- 'Handle'’s lifetime automatically. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. openTextFile :: FilePath -> IO.IOMode -> IO IO.Handle #ifdef SYSTEMFILEIO_LOCAL_OPEN_FILE openTextFile path mode = openFile' "openTextFile" path mode (Just IO.localeEncoding) #else openTextFile path = IO.openFile (encodeString path) #endif -- | Open a file in text mode, and pass its 'Handle' to a provided -- computation. The 'Handle' will be automatically closed when the -- computation returns. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. withTextFile :: FilePath -> IO.IOMode -> (IO.Handle -> IO a) -> IO a withTextFile path mode = Exc.bracket (openTextFile path mode) IO.hClose -- | Read in the entire content of a text file. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. readTextFile :: FilePath -> IO T.Text readTextFile path = openTextFile path IO.ReadMode >>= T.hGetContents -- | Replace the entire content of a text file with the provided -- 'T.Text'. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. writeTextFile :: FilePath -> T.Text -> IO () writeTextFile path text = withTextFile path IO.WriteMode (\h -> T.hPutStr h text) -- | Append 'T.Text' to a file. If the file does not exist, it will -- be created. -- -- This computation throws 'IOError' on failure. See “Classifying -- I/O errors” in the "System.IO.Error" documentation for information on -- why the failure occured. appendTextFile :: FilePath -> T.Text -> IO () appendTextFile path text = withTextFile path IO.AppendMode (\h -> T.hPutStr h text) #ifdef SYSTEMFILEIO_LOCAL_OPEN_FILE -- | Copied from GHC.IO.FD.openFile openFile' :: String -> FilePath -> IO.IOMode -> (Maybe IO.TextEncoding) -> IO IO.Handle openFile' loc path mode codec = open where sys_c_open = System.Posix.Internals.c_open sys_c_close = System.Posix.Internals.c_close flags = iomodeFlags mode open = withFilePath path $ \cPath -> do c_fd <- throwErrnoPathIfMinus1Retry loc path (sys_c_open cPath flags 0o666) (fd, fd_type) <- Exc.onException (mkFD c_fd mode Nothing False True) (sys_c_close c_fd) when (mode == IO.WriteMode && fd_type == GHC.IO.Device.RegularFile) $ do GHC.IO.Device.setSize fd 0 Exc.onException (mkHandleFromFD fd fd_type (encodeString path) mode False codec) (GHC.IO.Device.close fd) iomodeFlags :: IO.IOMode -> CInt iomodeFlags mode = cased .|. commonFlags where cased = case mode of IO.ReadMode -> flagsR #ifdef mingw32_HOST_OS IO.WriteMode -> flagsW .|. System.Posix.Internals.o_TRUNC #else IO.WriteMode -> flagsW #endif IO.ReadWriteMode -> flagsRW IO.AppendMode -> flagsA flagsR = System.Posix.Internals.o_RDONLY flagsW = outputFlags .|. System.Posix.Internals.o_WRONLY flagsRW = outputFlags .|. System.Posix.Internals.o_RDWR flagsA = flagsW .|. System.Posix.Internals.o_APPEND commonFlags = System.Posix.Internals.o_NOCTTY .|. System.Posix.Internals.o_NONBLOCK outputFlags = System.Posix.Internals.o_CREAT #endif #ifdef CABAL_OS_WINDOWS -- Only for accessing file or directory metadata. -- See issue #8. withHANDLE :: FilePath -> (Win32.HANDLE -> IO a) -> IO a withHANDLE path = Exc.bracket open close where open = Win32.createFile (encodeString path) 0 (Win32.fILE_SHARE_READ .|. Win32.fILE_SHARE_WRITE) Nothing Win32.oPEN_EXISTING Win32.fILE_FLAG_BACKUP_SEMANTICS Nothing close = Win32.closeHandle withFilePath :: FilePath -> (CWString -> IO a) -> IO a withFilePath path = withCWString (encodeString path) #else withFilePath :: FilePath -> (CString -> IO a) -> IO a withFilePath path = B.useAsCString (R.encode R.posix path) throwErrnoPathIfMinus1 :: String -> FilePath -> IO CInt -> IO CInt throwErrnoPathIfMinus1 loc path = CError.throwErrnoPathIfMinus1 loc (encodeString path) throwErrnoPathIfMinus1_ :: String -> FilePath -> IO CInt -> IO () throwErrnoPathIfMinus1_ loc path = CError.throwErrnoPathIfMinus1_ loc (encodeString path) throwErrnoPathIfNullRetry :: String -> FilePath -> IO (Ptr a) -> IO (Ptr a) throwErrnoPathIfNullRetry = throwErrnoPathIfRetry (== nullPtr) throwErrnoPathIfMinus1Retry :: String -> FilePath -> IO CInt -> IO CInt throwErrnoPathIfMinus1Retry = throwErrnoPathIfRetry (== -1) throwErrnoPathIfMinus1Retry_ :: String -> FilePath -> IO CInt -> IO () throwErrnoPathIfMinus1Retry_ = throwErrnoPathIfRetry_ (== -1) throwErrnoPathIfRetry :: (a -> Bool) -> String -> FilePath -> IO a -> IO a throwErrnoPathIfRetry failed loc path io = loop where loop = do a <- io if failed a then do errno <- CError.getErrno if errno == CError.eINTR then loop else CError.throwErrnoPath loc (encodeString path) else return a throwErrnoPathIfRetry_ :: (a -> Bool) -> String -> FilePath -> IO a -> IO () throwErrnoPathIfRetry_ failed loc path io = do _ <- throwErrnoPathIfRetry failed loc path io return () posixStat :: String -> FilePath -> IO Posix.FileStatus #if MIN_VERSION_unix(2,5,1) posixStat _ path = System.Posix.Files.ByteString.getFileStatus (R.encode R.posix path) #else posixStat loc path = withFd loc path Posix.getFdStatus withFd :: String -> FilePath -> (Posix.Fd -> IO a) -> IO a withFd fnName path = Exc.bracket open close where open = withFilePath path $ \cpath -> do fd <- throwErrnoPathIfMinus1 fnName path (c_open_nonblocking cpath 0) return (Posix.Fd fd) close = Posix.closeFd foreign import ccall unsafe "hssystemfileio_open_nonblocking" c_open_nonblocking :: CString -> CInt -> IO CInt #endif foreign import ccall unsafe "free" c_free :: Ptr a -> IO () #endif