{-# LANGUAGE CPP #-} #if !(MIN_VERSION_base(4,8,0)) -- In base-4.8.0 the Foreign module became Safe {-# LANGUAGE Trustworthy #-} #endif ----------------------------------------------------------------------------- -- | -- Module : System.Directory -- Copyright : (c) The University of Glasgow 2001 -- License : BSD-style (see the file libraries/base/LICENSE) -- -- Maintainer : libraries@haskell.org -- Stability : stable -- Portability : portable -- -- System-independent interface to directory manipulation. -- ----------------------------------------------------------------------------- #include <HsDirectoryConfig.h> module System.Directory ( -- $intro -- * Actions on directories createDirectory , createDirectoryIfMissing , removeDirectory , removeDirectoryRecursive , removePathForcibly , renameDirectory , listDirectory , getDirectoryContents -- ** Current working directory , getCurrentDirectory , setCurrentDirectory , withCurrentDirectory -- * Pre-defined directories , getHomeDirectory , XdgDirectory(..) , getXdgDirectory , getAppUserDataDirectory , getUserDocumentsDirectory , getTemporaryDirectory -- * Actions on files , removeFile , renameFile , renamePath , copyFile , copyFileWithMetadata , canonicalizePath , makeAbsolute , makeRelativeToCurrentDirectory , findExecutable , findExecutables , findExecutablesInDirectories , findFile , findFiles , findFileWith , findFilesWith , exeExtension , getFileSize -- * Existence tests , doesPathExist , doesFileExist , doesDirectoryExist -- * Symbolic links , pathIsSymbolicLink -- * Permissions -- $permissions , Permissions , emptyPermissions , readable , writable , executable , searchable , setOwnerReadable , setOwnerWritable , setOwnerExecutable , setOwnerSearchable , getPermissions , setPermissions , copyPermissions -- * Timestamps , getAccessTime , getModificationTime , setAccessTime , setModificationTime -- * Deprecated , isSymbolicLink ) where import Prelude () import System.Directory.Internal import System.Directory.Internal.Prelude import System.FilePath import Data.Time (UTCTime) import Data.Time.Clock.POSIX ( posixSecondsToUTCTime , utcTimeToPOSIXSeconds , POSIXTime ) #ifdef mingw32_HOST_OS import qualified System.Win32 as Win32 #else import qualified GHC.Foreign as GHC import qualified System.Posix as Posix #endif {- $intro A directory contains a series of entries, each of which is a named reference to a file system object (file, directory etc.). Some entries may be hidden, inaccessible, or have some administrative function (e.g. @.@ or @..@ under <http://www.opengroup.org/onlinepubs/009695399 POSIX>), but in this standard all such entries are considered to form part of the directory contents. Entries in sub-directories are not, however, considered to form part of the directory contents. Each file system object is referenced by a /path/. There is normally at least one absolute path to each file system object. In some operating systems, it may also be possible to have paths which are relative to the current directory. -} ----------------------------------------------------------------------------- -- Permissions {- $permissions The 'Permissions' type is used to record whether certain operations are permissible on a file\/directory. 'getPermissions' and 'setPermissions' get and set these permissions, respectively. Permissions apply both to files and directories. For directories, the executable field will be 'False', and for files the searchable field will be 'False'. Note that directories may be searchable without being readable, if permission has been given to use them as part of a path, but not to examine the directory contents. Note that to change some, but not all permissions, a construct on the following lines must be used. > makeReadable f = do > p <- getPermissions f > setPermissions f (p {readable = True}) -} data Permissions = Permissions { readable, writable, executable, searchable :: Bool } deriving (Eq, Ord, Read, Show) emptyPermissions :: Permissions emptyPermissions = Permissions { readable = False, writable = False, executable = False, searchable = False } setOwnerReadable :: Bool -> Permissions -> Permissions setOwnerReadable b p = p { readable = b } setOwnerWritable :: Bool -> Permissions -> Permissions setOwnerWritable b p = p { writable = b } setOwnerExecutable :: Bool -> Permissions -> Permissions setOwnerExecutable b p = p { executable = b } setOwnerSearchable :: Bool -> Permissions -> Permissions setOwnerSearchable b p = p { searchable = b } {- |The 'getPermissions' operation returns the permissions for the file or directory. The operation may fail with: * 'isPermissionError' if the user is not permitted to access the permissions; or * 'isDoesNotExistError' if the file or directory does not exist. -} getPermissions :: FilePath -> IO Permissions getPermissions name = #ifdef mingw32_HOST_OS -- issue #9: Windows doesn't like trailing path separators withFilePath (dropTrailingPathSeparator name) $ \s -> -- stat() does a better job of guessing the permissions on Windows -- than access() does. e.g. for execute permission, it looks at the -- filename extension :-) -- -- I tried for a while to do this properly, using the Windows security API, -- and eventually gave up. getPermissions is a flawed API anyway. -- SimonM allocaBytes sizeof_stat $ \ p_stat -> do throwErrnoIfMinus1_ "getPermissions" $ c_stat s p_stat mode <- st_mode p_stat let usr_read = mode .&. s_IRUSR let usr_write = mode .&. s_IWUSR let usr_exec = mode .&. s_IXUSR let is_dir = mode .&. s_IFDIR return ( Permissions { readable = usr_read /= 0, writable = usr_write /= 0, executable = is_dir == 0 && usr_exec /= 0, searchable = is_dir /= 0 && usr_exec /= 0 } ) #else do read_ok <- Posix.fileAccess name True False False write_ok <- Posix.fileAccess name False True False exec_ok <- Posix.fileAccess name False False True stat <- Posix.getFileStatus name let is_dir = Posix.isDirectory stat return ( Permissions { readable = read_ok, writable = write_ok, executable = not is_dir && exec_ok, searchable = is_dir && exec_ok } ) #endif {- |The 'setPermissions' operation sets the permissions for the file or directory. The operation may fail with: * 'isPermissionError' if the user is not permitted to set the permissions; or * 'isDoesNotExistError' if the file or directory does not exist. -} setPermissions :: FilePath -> Permissions -> IO () setPermissions name (Permissions r w e s) = #ifdef mingw32_HOST_OS allocaBytes sizeof_stat $ \ p_stat -> withFilePath name $ \p_name -> do throwErrnoIfMinus1_ "setPermissions" $ c_stat p_name p_stat throwErrnoIfMinus1_ "setPermissions" $ do mode <- st_mode p_stat let mode1 = modifyBit r mode s_IRUSR let mode2 = modifyBit w mode1 s_IWUSR let mode3 = modifyBit (e || s) mode2 s_IXUSR c_wchmod p_name mode3 where modifyBit :: Bool -> CMode -> CMode -> CMode modifyBit False m b = m .&. (complement b) modifyBit True m b = m .|. b #else do stat <- Posix.getFileStatus name let mode = Posix.fileMode stat let mode1 = modifyBit r mode Posix.ownerReadMode let mode2 = modifyBit w mode1 Posix.ownerWriteMode let mode3 = modifyBit (e || s) mode2 Posix.ownerExecuteMode Posix.setFileMode name mode3 where modifyBit :: Bool -> FileMode -> FileMode -> FileMode modifyBit False m b = m .&. (complement b) modifyBit True m b = m .|. b #endif copyPermissions :: FilePath -> FilePath -> IO () copyPermissions source dest = #ifdef mingw32_HOST_OS allocaBytes sizeof_stat $ \ p_stat -> withFilePath source $ \p_source -> withFilePath dest $ \p_dest -> do throwErrnoIfMinus1_ "copyPermissions" $ c_stat p_source p_stat mode <- st_mode p_stat throwErrnoIfMinus1_ "copyPermissions" $ c_wchmod p_dest mode #else do stat <- Posix.getFileStatus source copyPermissionsFromStatus stat dest #endif #ifndef mingw32_HOST_OS copyPermissionsFromStatus :: Posix.FileStatus -> FilePath -> IO () copyPermissionsFromStatus st dst = do Posix.setFileMode dst (Posix.fileMode st) #endif ----------------------------------------------------------------------------- -- Implementation {- |@'createDirectory' dir@ creates a new directory @dir@ which is initially empty, or as near to empty as the operating system allows. The operation may fail with: * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES]@ * 'isAlreadyExistsError' \/ 'AlreadyExists' The operand refers to a directory that already exists. @ [EEXIST]@ * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'NoSuchThing' There is no path to the directory. @[ENOENT, ENOTDIR]@ * 'ResourceExhausted' Insufficient resources (virtual memory, process file descriptors, physical disk space, etc.) are available to perform the operation. @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ * 'InappropriateType' The path refers to an existing non-directory object. @[EEXIST]@ -} createDirectory :: FilePath -> IO () createDirectory path = do #ifdef mingw32_HOST_OS Win32.createDirectory path Nothing #else Posix.createDirectory path 0o777 #endif -- | @'createDirectoryIfMissing' parents dir@ creates a new directory -- @dir@ if it doesn\'t exist. If the first argument is 'True' -- the function will also create all parent directories if they are missing. createDirectoryIfMissing :: Bool -- ^ Create its parents too? -> FilePath -- ^ The path to the directory you want to make -> IO () createDirectoryIfMissing create_parents path0 | create_parents = createDirs (parents path0) | otherwise = createDirs (take 1 (parents path0)) where parents = reverse . scanl1 (</>) . splitDirectories . normalise createDirs [] = return () createDirs (dir:[]) = createDir dir ioError createDirs (dir:dirs) = createDir dir $ \_ -> do createDirs dirs createDir dir ioError createDir dir notExistHandler = do r <- tryIOError (createDirectory dir) case r of Right () -> return () Left e | isDoesNotExistError e -> notExistHandler e -- createDirectory (and indeed POSIX mkdir) does not distinguish -- between a dir already existing and a file already existing. So we -- check for it here. Unfortunately there is a slight race condition -- here, but we think it is benign. It could report an exeption in -- the case that the dir did exist but another process deletes the -- directory and creates a file in its place before we can check -- that the directory did indeed exist. -- We also follow this path when we get a permissions error, as -- trying to create "." when in the root directory on Windows -- fails with -- CreateDirectory ".": permission denied (Access is denied.) -- This caused GHCi to crash when loading a module in the root -- directory. | isAlreadyExistsError e || isPermissionError e -> do canIgnore <- isDir `catchIOError` \ _ -> return (isAlreadyExistsError e) unless canIgnore (ioError e) | otherwise -> ioError e where #ifdef mingw32_HOST_OS isDir = withFileStatus "createDirectoryIfMissing" dir isDirectory #else isDir = (Posix.isDirectory <$> Posix.getFileStatus dir) #endif -- | * @'NotDirectory'@: not a directory. -- * @'Directory'@: a true directory (not a symbolic link). -- * @'DirectoryLink'@: a directory symbolic link (only exists on Windows). data DirectoryType = NotDirectory | Directory | DirectoryLink deriving (Enum, Eq, Ord, Read, Show) -- | Obtain the type of a directory. getDirectoryType :: FilePath -> IO DirectoryType getDirectoryType path = (`ioeAddLocation` "getDirectoryType") `modifyIOError` do #ifdef mingw32_HOST_OS isDir <- withFileStatus "getDirectoryType" path isDirectory if isDir then do isLink <- pathIsSymbolicLink path if isLink then return DirectoryLink else return Directory else do return NotDirectory #else stat <- Posix.getSymbolicLinkStatus path return $ if Posix.isDirectory stat then Directory else NotDirectory #endif {- | @'removeDirectory' dir@ removes an existing directory /dir/. The implementation may specify additional constraints which must be satisfied before a directory can be removed (e.g. the directory has to be empty, or may not be in use by other processes). It is not legal for an implementation to partially remove a directory unless the entire directory is removed. A conformant implementation need not support directory removal in all situations (e.g. removal of the root directory). The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The directory does not exist. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY, ENOTEMPTY, EEXIST]@ * 'UnsupportedOperation' The implementation does not support removal in this situation. @[EINVAL]@ * 'InappropriateType' The operand refers to an existing non-directory object. @[ENOTDIR]@ -} removeDirectory :: FilePath -> IO () removeDirectory path = #ifdef mingw32_HOST_OS Win32.removeDirectory path #else Posix.removeDirectory path #endif -- | @'removeDirectoryRecursive' dir@ removes an existing directory /dir/ -- together with its contents and subdirectories. Within this directory, -- symbolic links are removed without affecting their targets. -- -- On Windows, the operation fails if /dir/ is a directory symbolic link. removeDirectoryRecursive :: FilePath -> IO () removeDirectoryRecursive path = (`ioeAddLocation` "removeDirectoryRecursive") `modifyIOError` do dirType <- getDirectoryType path case dirType of Directory -> removeContentsRecursive path DirectoryLink -> ioError (err `ioeSetErrorString` "is a directory symbolic link") NotDirectory -> ioError (err `ioeSetErrorString` "not a directory") where err = mkIOError InappropriateType "" Nothing (Just path) -- | @'removePathRecursive' path@ removes an existing file or directory at -- /path/ together with its contents and subdirectories. Symbolic links are -- removed without affecting their the targets. removePathRecursive :: FilePath -> IO () removePathRecursive path = (`ioeAddLocation` "removePathRecursive") `modifyIOError` do dirType <- getDirectoryType path case dirType of NotDirectory -> removeFile path Directory -> removeContentsRecursive path DirectoryLink -> removeDirectory path -- | @'removeContentsRecursive' dir@ removes the contents of the directory -- /dir/ recursively. Symbolic links are removed without affecting their the -- targets. removeContentsRecursive :: FilePath -> IO () removeContentsRecursive path = (`ioeAddLocation` "removeContentsRecursive") `modifyIOError` do cont <- listDirectory path mapM_ removePathRecursive [path </> x | x <- cont] removeDirectory path -- | Removes a file or directory at /path/ together with its contents and -- subdirectories. Symbolic links are removed without affecting their -- targets. If the path does not exist, nothing happens. -- -- Unlike other removal functions, this function will also attempt to delete -- files marked as read-only or otherwise made unremovable due to permissions. -- As a result, if the removal is incomplete, the permissions or attributes on -- the remaining files may be altered. If there are hard links in the -- directory, then permissions on all related hard links may be altered. -- -- If an entry within the directory vanishes while @removePathForcibly@ is -- running, it is silently ignored. -- -- If an exception occurs while removing an entry, @removePathForcibly@ will -- still try to remove as many entries as it can before failing with an -- exception. The first exception that it encountered is re-thrown. -- -- @since 1.2.7.0 removePathForcibly :: FilePath -> IO () removePathForcibly path = (`ioeAddLocation` "removePathForcibly") `modifyIOError` do makeRemovable path `catchIOError` \ _ -> return () ignoreDoesNotExistError $ do dirType <- getDirectoryType path case dirType of NotDirectory -> removeFile path DirectoryLink -> removeDirectory path Directory -> do names <- listDirectory path sequenceWithIOErrors_ $ [ removePathForcibly (path </> name) | name <- names ] ++ [ removeDirectory path ] where ignoreDoesNotExistError :: IO () -> IO () ignoreDoesNotExistError action = do _ <- tryIOErrorType isDoesNotExistError action return () makeRemovable :: FilePath -> IO () makeRemovable p = do perms <- getPermissions p setPermissions path perms{ readable = True , searchable = True , writable = True } sequenceWithIOErrors_ :: [IO ()] -> IO () sequenceWithIOErrors_ actions = go (Right ()) actions where go :: Either IOError () -> [IO ()] -> IO () go (Left e) [] = ioError e go (Right ()) [] = return () go s (m : ms) = s `seq` do r <- tryIOError m go (thenEither s r) ms -- equivalent to (*>) for Either, defined here to retain compatibility -- with base prior to 4.3 thenEither :: Either b a -> Either b a -> Either b a thenEither x@(Left _) _ = x thenEither _ y = y {- |'removeFile' /file/ removes the directory entry for an existing file /file/, where /file/ is not itself a directory. The implementation may specify additional constraints which must be satisfied before a file can be removed (e.g. the file may not be in use by other processes). The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid file name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The file does not exist. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY]@ * 'InappropriateType' The operand refers to an existing directory. @[EPERM, EINVAL]@ -} removeFile :: FilePath -> IO () removeFile path = #ifdef mingw32_HOST_OS Win32.deleteFile path #else Posix.removeLink path #endif {- |@'renameDirectory' old new@ changes the name of an existing directory from /old/ to /new/. If the /new/ directory already exists, it is atomically replaced by the /old/ directory. If the /new/ directory is neither the /old/ directory nor an alias of the /old/ directory, it is removed as if by 'removeDirectory'. A conformant implementation need not support renaming directories in all situations (e.g. renaming to an existing directory, or across different physical devices), but the constraints must be documented. On Win32 platforms, @renameDirectory@ fails if the /new/ directory already exists. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' Either operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The original directory does not exist, or there is no path to the target. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'ResourceExhausted' Insufficient resources are available to perform the operation. @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY, ENOTEMPTY, EEXIST]@ * 'UnsupportedOperation' The implementation does not support renaming in this situation. @[EINVAL, EXDEV]@ * 'InappropriateType' Either path refers to an existing non-directory object. @[ENOTDIR, EISDIR]@ -} renameDirectory :: FilePath -> FilePath -> IO () renameDirectory opath npath = -- XXX this test isn't performed atomically with the following rename #ifdef mingw32_HOST_OS -- ToDo: use Win32 API withFileStatus "renameDirectory" opath $ \st -> do is_dir <- isDirectory st #else do stat <- Posix.getFileStatus opath let is_dir = Posix.fileMode stat .&. Posix.directoryMode /= 0 #endif when (not is_dir) $ do ioError . (`ioeSetErrorString` "not a directory") $ (mkIOError InappropriateType "renameDirectory" Nothing (Just opath)) renamePath opath npath {- |@'renameFile' old new@ changes the name of an existing file system object from /old/ to /new/. If the /new/ object already exists, it is atomically replaced by the /old/ object. Neither path may refer to an existing directory. A conformant implementation need not support renaming files in all situations (e.g. renaming across different physical devices), but the constraints must be documented. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' Either operand is not a valid file name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The original file does not exist, or there is no path to the target. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'ResourceExhausted' Insufficient resources are available to perform the operation. @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY]@ * 'UnsupportedOperation' The implementation does not support renaming in this situation. @[EXDEV]@ * 'InappropriateType' Either path refers to an existing directory. @[ENOTDIR, EISDIR, EINVAL, EEXIST, ENOTEMPTY]@ -} renameFile :: FilePath -> FilePath -> IO () renameFile opath npath = (`ioeAddLocation` "renameFile") `modifyIOError` do -- XXX the tests are not performed atomically with the rename checkNotDir opath renamePath opath npath -- The underlying rename implementation can throw odd exceptions when the -- destination is a directory. For example, Windows typically throws a -- permission error, while POSIX systems may throw a resource busy error -- if one of the paths refers to the current directory. In these cases, -- we check if the destination is a directory and, if so, throw an -- InappropriateType error. `catchIOError` \ err -> do checkNotDir npath ioError err where checkNotDir path = do dirType <- getDirectoryType path `catchIOError` \ _ -> return NotDirectory case dirType of Directory -> errIsDir path DirectoryLink -> errIsDir path NotDirectory -> return () errIsDir path = ioError . (`ioeSetErrorString` "is a directory") $ mkIOError InappropriateType "" Nothing (Just path) -- | Rename a file or directory. If the destination path already exists, it -- is replaced atomically. The destination path must not point to an existing -- directory. A conformant implementation need not support renaming files in -- all situations (e.g. renaming across different physical devices), but the -- constraints must be documented. -- -- The operation may fail with: -- -- * 'HardwareFault' -- A physical I\/O error has occurred. -- @[EIO]@ -- -- * 'InvalidArgument' -- Either operand is not a valid file name. -- @[ENAMETOOLONG, ELOOP]@ -- -- * 'isDoesNotExistError' \/ 'NoSuchThing' -- The original file does not exist, or there is no path to the target. -- @[ENOENT, ENOTDIR]@ -- -- * 'isPermissionError' \/ 'PermissionDenied' -- The process has insufficient privileges to perform the operation. -- @[EROFS, EACCES, EPERM]@ -- -- * 'ResourceExhausted' -- Insufficient resources are available to perform the operation. -- @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ -- -- * 'UnsatisfiedConstraints' -- Implementation-dependent constraints are not satisfied. -- @[EBUSY]@ -- -- * 'UnsupportedOperation' -- The implementation does not support renaming in this situation. -- @[EXDEV]@ -- -- * 'InappropriateType' -- Either the destination path refers to an existing directory, or one of the -- parent segments in the destination path is not a directory. -- @[ENOTDIR, EISDIR, EINVAL, EEXIST, ENOTEMPTY]@ -- -- @since 1.2.7.0 renamePath :: FilePath -- ^ Old path -> FilePath -- ^ New path -> IO () renamePath opath npath = (`ioeAddLocation` "renamePath") `modifyIOError` do #ifdef mingw32_HOST_OS Win32.moveFileEx opath npath Win32.mOVEFILE_REPLACE_EXISTING #else Posix.rename opath npath #endif -- | Copy a file with its permissions. If the destination file already exists, -- it is replaced atomically. Neither path may refer to an existing -- directory. No exceptions are thrown if the permissions could not be -- copied. copyFile :: FilePath -- ^ Source filename -> FilePath -- ^ Destination filename -> IO () copyFile fromFPath toFPath = (`ioeAddLocation` "copyFile") `modifyIOError` do atomicCopyFileContents fromFPath toFPath (ignoreIOExceptions . copyPermissions fromFPath) #ifndef mingw32_HOST_OS -- | Truncate the destination file and then copy the contents of the source -- file to the destination file. If the destination file already exists, its -- attributes shall remain unchanged. Otherwise, its attributes are reset to -- the defaults. copyFileContents :: FilePath -- ^ Source filename -> FilePath -- ^ Destination filename -> IO () copyFileContents fromFPath toFPath = (`ioeAddLocation` "copyFileContents") `modifyIOError` do withBinaryFile toFPath WriteMode $ \ hTo -> copyFileToHandle fromFPath hTo #endif -- | Copy the contents of a source file to a destination file, replacing the -- destination file atomically via 'withReplacementFile', resetting the -- attributes of the destination file to the defaults. atomicCopyFileContents :: FilePath -- ^ Source filename -> FilePath -- ^ Destination filename -> (FilePath -> IO ()) -- ^ Post-action -> IO () atomicCopyFileContents fromFPath toFPath postAction = (`ioeAddLocation` "atomicCopyFileContents") `modifyIOError` do withReplacementFile toFPath postAction $ \ hTo -> do copyFileToHandle fromFPath hTo -- | A helper function useful for replacing files in an atomic manner. The -- function creates a temporary file in the directory of the destination file, -- opens it, performs the main action with its handle, closes it, performs the -- post-action with its path, and finally replaces the destination file with -- the temporary file. If an error occurs during any step of this process, -- the temporary file is removed and the destination file remains untouched. withReplacementFile :: FilePath -- ^ Destination file -> (FilePath -> IO ()) -- ^ Post-action -> (Handle -> IO a) -- ^ Main action -> IO a withReplacementFile path postAction action = (`ioeAddLocation` "withReplacementFile") `modifyIOError` do mask $ \ restore -> do (tmpFPath, hTmp) <- openBinaryTempFile (takeDirectory path) ".copyFile.tmp" (`onException` ignoreIOExceptions (removeFile tmpFPath)) $ do r <- (`onException` ignoreIOExceptions (hClose hTmp)) $ do restore (action hTmp) hClose hTmp restore (postAction tmpFPath) renameFile tmpFPath path return r -- | Attempt to perform the given action, silencing any IO exception thrown by -- it. ignoreIOExceptions :: IO () -> IO () ignoreIOExceptions io = io `catchIOError` (\_ -> return ()) -- | Copy all data from a file to a handle. copyFileToHandle :: FilePath -- ^ Source file -> Handle -- ^ Destination handle -> IO () copyFileToHandle fromFPath hTo = (`ioeAddLocation` "copyFileToHandle") `modifyIOError` do withBinaryFile fromFPath ReadMode $ \ hFrom -> copyHandleData hFrom hTo -- | Copy data from one handle to another until end of file. copyHandleData :: Handle -- ^ Source handle -> Handle -- ^ Destination handle -> IO () copyHandleData hFrom hTo = (`ioeAddLocation` "copyData") `modifyIOError` do allocaBytes bufferSize go where bufferSize = 131072 -- 128 KiB, as coreutils `cp` uses as of May 2014 (see ioblksize.h) go buffer = do count <- hGetBuf hFrom buffer bufferSize when (count > 0) $ do hPutBuf hTo buffer count go buffer -- | Copy a file with its associated metadata. If the destination file -- already exists, it is overwritten. There is no guarantee of atomicity in -- the replacement of the destination file. Neither path may refer to an -- existing directory. If the source and/or destination are symbolic links, -- the copy is performed on the targets of the links. -- -- On Windows, it behaves like the Win32 function -- <https://msdn.microsoft.com/en-us/library/windows/desktop/aa363851.aspx CopyFile>, -- which copies various kinds of metadata including file attributes and -- security resource properties. -- -- On Unix-like systems, permissions, access time, and modification time are -- preserved. If possible, the owner and group are also preserved. Note that -- the very act of copying can change the access time of the source file, -- hence the access times of the two files may differ after the operation -- completes. -- -- @since 1.2.6.0 copyFileWithMetadata :: FilePath -- ^ Source file -> FilePath -- ^ Destination file -> IO () copyFileWithMetadata src dst = (`ioeAddLocation` "copyFileWithMetadata") `modifyIOError` doCopy where #ifdef mingw32_HOST_OS doCopy = Win32.copyFile src dst False #else doCopy = do st <- Posix.getFileStatus src copyFileContents src dst copyMetadataFromStatus st dst #endif #ifndef mingw32_HOST_OS copyMetadataFromStatus :: Posix.FileStatus -> FilePath -> IO () copyMetadataFromStatus st dst = do tryCopyOwnerAndGroupFromStatus st dst copyPermissionsFromStatus st dst copyFileTimesFromStatus st dst #endif #ifndef mingw32_HOST_OS tryCopyOwnerAndGroupFromStatus :: Posix.FileStatus -> FilePath -> IO () tryCopyOwnerAndGroupFromStatus st dst = do ignoreIOExceptions (copyOwnerFromStatus st dst) ignoreIOExceptions (copyGroupFromStatus st dst) #endif #ifndef mingw32_HOST_OS copyOwnerFromStatus :: Posix.FileStatus -> FilePath -> IO () copyOwnerFromStatus st dst = do Posix.setOwnerAndGroup dst (Posix.fileOwner st) (-1) #endif #ifndef mingw32_HOST_OS copyGroupFromStatus :: Posix.FileStatus -> FilePath -> IO () copyGroupFromStatus st dst = do Posix.setOwnerAndGroup dst (-1) (Posix.fileGroup st) #endif #ifndef mingw32_HOST_OS copyFileTimesFromStatus :: Posix.FileStatus -> FilePath -> IO () copyFileTimesFromStatus st dst = do let (atime, mtime) = fileTimesFromStatus st setFileTimes dst (Just atime, Just mtime) #endif -- | Make a path absolute, 'normalise' the path, and remove as many -- indirections from it as possible. Any trailing path separators are -- discarded via 'dropTrailingPathSeparator'. Additionally, on Windows the -- letter case of the path is canonicalized. -- -- __Note__: This function is a very big hammer. If you only need an absolute -- path, 'makeAbsolute' is sufficient for removing dependence on the current -- working directory. -- -- Indirections include the two special directories @.@ and @..@, as well as -- any symbolic links. The input path need not point to an existing file or -- directory. Canonicalization is performed on the longest prefix of the path -- that points to an existing file or directory. The remaining portion of the -- path that does not point to an existing file or directory will still -- undergo 'normalise', but case canonicalization and indirection removal are -- skipped as they are impossible to do on a nonexistent path. -- -- Most programs should not worry about the canonicity of a path. In -- particular, despite the name, the function does not truly guarantee -- canonicity of the returned path due to the presence of hard links, mount -- points, etc. -- -- If the path points to an existing file or directory, then the output path -- shall also point to the same file or directory, subject to the condition -- that the relevant parts of the file system do not change while the function -- is still running. In other words, the function is definitively not atomic. -- The results can be utterly wrong if the portions of the path change while -- this function is running. -- -- Since symbolic links (and, on non-Windows systems, parent directories @..@) -- are dependent on the state of the existing filesystem, the function can -- only make a conservative attempt by removing such indirections from the -- longest prefix of the path that still points to an existing file or -- directory. -- -- Note that on Windows parent directories @..@ are always fully expanded -- before the symbolic links, as consistent with the rest of the Windows API -- (such as @GetFullPathName@). In contrast, on POSIX systems parent -- directories @..@ are expanded alongside symbolic links from left to right. -- To put this more concretely: if @L@ is a symbolic link for @R/P@, then on -- Windows @L\\..@ refers to @.@, whereas on other operating systems @L/..@ -- refers to @R@. -- -- Similar to 'normalise', passing an empty path is equivalent to passing the -- current directory. -- -- /Known bugs/: When the path contains an existing symbolic link, but the -- target of the link does not exist, then the path is not dereferenced (bug -- #64). Symbolic link expansion is not performed on Windows XP or earlier -- due to the absence of @GetFinalPathNameByHandle@. -- -- /Changes since 1.2.3.0:/ The function has been altered to be more robust -- and has the same exception behavior as 'makeAbsolute'. -- -- /Changes since 1.3.0.0:/ The function no longer preserves the trailing path -- separator. File symbolic links that appear in the middle of a path are -- properly dereferenced. Case canonicalization and symbolic link expansion -- are now performed on Windows. -- canonicalizePath :: FilePath -> IO FilePath canonicalizePath = \ path -> modifyIOError ((`ioeAddLocation` "canonicalizePath") . (`ioeSetFileName` path)) $ -- normalise does more stuff, like upper-casing the drive letter dropTrailingPathSeparator . normalise <$> (transform =<< prependCurrentDirectory path) where #if defined(mingw32_HOST_OS) transform path = attemptRealpath getFinalPathName =<< (Win32.getFullPathName path `catchIOError` \ _ -> return path) #else transform path = do encoding <- getFileSystemEncoding let realpath path' = GHC.withCString encoding path' (`withRealpath` GHC.peekCString encoding) attemptRealpath realpath path #endif attemptRealpath realpath path = realpathPrefix realpath (reverse (zip prefixes suffixes)) path where segments = splitDirectories path prefixes = scanl1 (</>) segments suffixes = tail (scanr (</>) "" segments) -- call realpath on the largest possible prefix realpathPrefix realpath ((prefix, suffix) : rest) path = do exist <- doesPathExist prefix if exist -- never call realpath on an inaccessible path then ((</> suffix) <$> realpath prefix) `catchIOError` \ _ -> realpathPrefix realpath rest path else realpathPrefix realpath rest path realpathPrefix _ _ path = return path -- | Convert a path into an absolute path. If the given path is relative, the -- current directory is prepended and then the combined result is -- 'normalise'd. If the path is already absolute, the path is simply -- 'normalise'd. The function preserves the presence or absence of the -- trailing path separator unless the path refers to the root directory @/@. -- -- If the path is already absolute, the operation never fails. Otherwise, the -- operation may fail with the same exceptions as 'getCurrentDirectory'. -- -- @since 1.2.2.0 -- makeAbsolute :: FilePath -> IO FilePath makeAbsolute path = modifyIOError ((`ioeAddLocation` "makeAbsolute") . (`ioeSetFileName` path)) $ matchTrailingSeparator path . normalise <$> prependCurrentDirectory path -- | Convert a path into an absolute path. If the given path is relative, the -- current directory is prepended. If the path is already absolute, the path -- is returned unchanged. The function preserves the presence or absence of -- the trailing path separator. -- -- If the path is already absolute, the operation never fails. Otherwise, the -- operation may fail with the same exceptions as 'getCurrentDirectory'. -- -- (internal API) prependCurrentDirectory :: FilePath -> IO FilePath prependCurrentDirectory path = modifyIOError ((`ioeAddLocation` "prependCurrentDirectory") . (`ioeSetFileName` path)) $ if isRelative path -- avoid the call to `getCurrentDirectory` if we can then (</> path) <$> getCurrentDirectory else return path -- | Add or remove the trailing path separator in the second path so as to -- match its presence in the first path. -- -- (internal API) matchTrailingSeparator :: FilePath -> FilePath -> FilePath matchTrailingSeparator path | hasTrailingPathSeparator path = addTrailingPathSeparator | otherwise = dropTrailingPathSeparator -- | Construct a path relative to the current directory, similar to -- 'makeRelative'. -- -- The operation may fail with the same exceptions as 'getCurrentDirectory'. makeRelativeToCurrentDirectory :: FilePath -> IO FilePath makeRelativeToCurrentDirectory x = do cur <- getCurrentDirectory return $ makeRelative cur x -- | Given an executable file name, searches for such file in the -- directories listed in system PATH. The returned value is the path -- to the found executable or Nothing if an executable with the given -- name was not found. For example (findExecutable \"ghc\") gives you -- the path to GHC. -- -- The path returned by 'findExecutable' corresponds to the -- program that would be executed by 'System.Process.createProcess' -- when passed the same string (as a RawCommand, not a ShellCommand). -- -- On Windows, 'findExecutable' calls the Win32 function 'SearchPath', -- which may search other places before checking the directories in -- @PATH@. Where it actually searches depends on registry settings, -- but notably includes the directory containing the current -- executable. See -- <http://msdn.microsoft.com/en-us/library/aa365527.aspx> for more -- details. -- findExecutable :: String -> IO (Maybe FilePath) findExecutable binary = do #if defined(mingw32_HOST_OS) Win32.searchPath Nothing binary exeExtension #else path <- getPath findFileWith isExecutable path (binary <.> exeExtension) #endif -- | Given a file name, searches for the file and returns a list of all -- occurences that are executable. -- -- On Windows, this only returns the first ocurrence, if any. It uses the -- @SearchPath@ from the Win32 API, so the caveats noted in 'findExecutable' -- apply here as well. -- -- @since 1.2.2.0 findExecutables :: String -> IO [FilePath] findExecutables binary = do #if defined(mingw32_HOST_OS) file <- findExecutable binary return $ maybeToList file #else path <- getPath findExecutablesInDirectories path binary #endif #ifndef mingw32_HOST_OS -- | Get the contents of the @PATH@ environment variable. getPath :: IO [FilePath] getPath = do path <- getEnv "PATH" return (splitSearchPath path) #endif -- | Given a file name, searches for the file on the given paths and returns a -- list of all occurences that are executable. -- -- @since 1.2.4.0 findExecutablesInDirectories :: [FilePath] -> String -> IO [FilePath] findExecutablesInDirectories path binary = findFilesWith isExecutable path (binary <.> exeExtension) -- | Test whether a file is executable. isExecutable :: FilePath -> IO Bool isExecutable file = do perms <- getPermissions file return (executable perms) -- | Search through the given set of directories for the given file. findFile :: [FilePath] -> String -> IO (Maybe FilePath) findFile = findFileWith (\_ -> return True) -- | Search through the given set of directories for the given file and -- returns a list of paths where the given file exists. -- -- @since 1.2.1.0 findFiles :: [FilePath] -> String -> IO [FilePath] findFiles = findFilesWith (\_ -> return True) -- | Search through the given set of directories for the given file and -- with the given property (usually permissions) and returns the file path -- where the given file exists and has the property. -- -- @since 1.2.6.0 findFileWith :: (FilePath -> IO Bool) -> [FilePath] -> String -> IO (Maybe FilePath) findFileWith f ds name = asumMaybeT (map (findFileWithIn f name) ds) -- | 'Data.Foldable.asum' for 'Control.Monad.Trans.Maybe.MaybeT', essentially. -- -- Returns the first 'Just' in the list or 'Nothing' if there aren't any. asumMaybeT :: Monad m => [m (Maybe a)] -> m (Maybe a) asumMaybeT = foldr attempt (return Nothing) where attempt mmx mx' = do mx <- mmx case mx of Nothing -> mx' Just _ -> return mx -- | Search through the given set of directories for the given file and -- with the given property (usually permissions) and returns a list of -- paths where the given file exists and has the property. -- -- @since 1.2.1.0 findFilesWith :: (FilePath -> IO Bool) -> [FilePath] -> String -> IO [FilePath] findFilesWith f ds name = do mfiles <- mapM (findFileWithIn f name) ds return (catMaybes mfiles) -- | Like 'findFileWith', but searches only a single directory. findFileWithIn :: (FilePath -> IO Bool) -> String -> FilePath -> IO (Maybe FilePath) findFileWithIn f name d = do let path = d </> name exist <- doesFileExist path if exist then do ok <- f path if ok then return (Just path) else return Nothing else return Nothing -- | Similar to 'listDirectory', but always includes the special entries (@.@ -- and @..@). (This applies to Windows as well.) -- -- The operation may fail with the same exceptions as 'listDirectory'. getDirectoryContents :: FilePath -> IO [FilePath] getDirectoryContents path = modifyIOError ((`ioeSetFileName` path) . (`ioeAddLocation` "getDirectoryContents")) $ do #ifndef mingw32_HOST_OS bracket (Posix.openDirStream path) Posix.closeDirStream start where start dirp = loop id where loop acc = do e <- Posix.readDirStream dirp if null e then return (acc []) else loop (acc . (e:)) #else bracket (Win32.findFirstFile (path </> "*")) (\(h,_) -> Win32.findClose h) (\(h,fdat) -> loop h fdat []) where -- we needn't worry about empty directories: adirectory always -- has at least "." and ".." entries loop :: Win32.HANDLE -> Win32.FindData -> [FilePath] -> IO [FilePath] loop h fdat acc = do filename <- Win32.getFindDataFileName fdat more <- Win32.findNextFile h fdat if more then loop h fdat (filename:acc) else return (filename:acc) -- no need to reverse, ordering is undefined #endif /* mingw32 */ -- | @'listDirectory' dir@ returns a list of /all/ entries in /dir/ without -- the special entries (@.@ and @..@). -- -- The operation may fail with: -- -- * 'HardwareFault' -- A physical I\/O error has occurred. -- @[EIO]@ -- -- * 'InvalidArgument' -- The operand is not a valid directory name. -- @[ENAMETOOLONG, ELOOP]@ -- -- * 'isDoesNotExistError' \/ 'NoSuchThing' -- The directory does not exist. -- @[ENOENT, ENOTDIR]@ -- -- * 'isPermissionError' \/ 'PermissionDenied' -- The process has insufficient privileges to perform the operation. -- @[EACCES]@ -- -- * 'ResourceExhausted' -- Insufficient resources are available to perform the operation. -- @[EMFILE, ENFILE]@ -- -- * 'InappropriateType' -- The path refers to an existing non-directory object. -- @[ENOTDIR]@ -- -- @since 1.2.5.0 -- listDirectory :: FilePath -> IO [FilePath] listDirectory path = (filter f) <$> (getDirectoryContents path) where f filename = filename /= "." && filename /= ".." -- | Obtain the current working directory as an absolute path. -- -- In a multithreaded program, the current working directory is a global state -- shared among all threads of the process. Therefore, when performing -- filesystem operations from multiple threads, it is highly recommended to -- use absolute rather than relative paths (see: 'makeAbsolute'). -- -- The operation may fail with: -- -- * 'HardwareFault' -- A physical I\/O error has occurred. -- @[EIO]@ -- -- * 'isDoesNotExistError' or 'NoSuchThing' -- There is no path referring to the working directory. -- @[EPERM, ENOENT, ESTALE...]@ -- -- * 'isPermissionError' or 'PermissionDenied' -- The process has insufficient privileges to perform the operation. -- @[EACCES]@ -- -- * 'ResourceExhausted' -- Insufficient resources are available to perform the operation. -- -- * 'UnsupportedOperation' -- The operating system has no notion of current working directory. -- getCurrentDirectory :: IO FilePath getCurrentDirectory = modifyIOError (`ioeAddLocation` "getCurrentDirectory") $ specializeErrorString "Current working directory no longer exists" isDoesNotExistError getCwd where #ifdef mingw32_HOST_OS getCwd = Win32.getCurrentDirectory #else getCwd = Posix.getWorkingDirectory #endif -- | Change the working directory to the given path. -- -- In a multithreaded program, the current working directory is a global state -- shared among all threads of the process. Therefore, when performing -- filesystem operations from multiple threads, it is highly recommended to -- use absolute rather than relative paths (see: 'makeAbsolute'). -- -- The operation may fail with: -- -- * 'HardwareFault' -- A physical I\/O error has occurred. -- @[EIO]@ -- -- * 'InvalidArgument' -- The operand is not a valid directory name. -- @[ENAMETOOLONG, ELOOP]@ -- -- * 'isDoesNotExistError' or 'NoSuchThing' -- The directory does not exist. -- @[ENOENT, ENOTDIR]@ -- -- * 'isPermissionError' or 'PermissionDenied' -- The process has insufficient privileges to perform the operation. -- @[EACCES]@ -- -- * 'UnsupportedOperation' -- The operating system has no notion of current working directory, or the -- working directory cannot be dynamically changed. -- -- * 'InappropriateType' -- The path refers to an existing non-directory object. -- @[ENOTDIR]@ -- setCurrentDirectory :: FilePath -> IO () setCurrentDirectory = #ifdef mingw32_HOST_OS Win32.setCurrentDirectory #else Posix.changeWorkingDirectory #endif -- | Run an 'IO' action with the given working directory and restore the -- original working directory afterwards, even if the given action fails due -- to an exception. -- -- The operation may fail with the same exceptions as 'getCurrentDirectory' -- and 'setCurrentDirectory'. -- -- @since 1.2.3.0 -- withCurrentDirectory :: FilePath -- ^ Directory to execute in -> IO a -- ^ Action to be executed -> IO a withCurrentDirectory dir action = bracket getCurrentDirectory setCurrentDirectory $ \ _ -> do setCurrentDirectory dir action -- | Obtain the size of a file in bytes. -- -- @since 1.2.7.0 getFileSize :: FilePath -> IO Integer getFileSize path = (`ioeAddLocation` "getFileSize") `modifyIOError` do #ifdef mingw32_HOST_OS fromIntegral <$> withFileStatus "" path st_size #else fromIntegral . Posix.fileSize <$> Posix.getFileStatus path #endif -- | Test whether the given path points to an existing filesystem object. If -- the user lacks necessary permissions to search the parent directories, this -- function may return false even if the file does actually exist. -- -- @since 1.2.7.0 doesPathExist :: FilePath -> IO Bool doesPathExist path = #ifdef mingw32_HOST_OS (withFileStatus "" path $ \ _ -> return True) #else (Posix.getFileStatus path >> return True) #endif `catchIOError` \ _ -> return False {- |The operation 'doesDirectoryExist' returns 'True' if the argument file exists and is either a directory or a symbolic link to a directory, and 'False' otherwise. -} doesDirectoryExist :: FilePath -> IO Bool doesDirectoryExist name = #ifdef mingw32_HOST_OS (withFileStatus "doesDirectoryExist" name $ \st -> isDirectory st) #else (do stat <- Posix.getFileStatus name return (Posix.isDirectory stat)) #endif `catchIOError` \ _ -> return False {- |The operation 'doesFileExist' returns 'True' if the argument file exists and is not a directory, and 'False' otherwise. -} doesFileExist :: FilePath -> IO Bool doesFileExist name = #ifdef mingw32_HOST_OS (withFileStatus "doesFileExist" name $ \st -> do b <- isDirectory st; return (not b)) #else (do stat <- Posix.getFileStatus name return (not (Posix.isDirectory stat))) #endif `catchIOError` \ _ -> return False -- | Check whether the path refers to a symbolic link. On Windows, this tests -- for @FILE_ATTRIBUTE_REPARSE_POINT@. -- -- @since 1.3.0.0 pathIsSymbolicLink :: FilePath -> IO Bool pathIsSymbolicLink path = (`ioeAddLocation` "getDirectoryType") `modifyIOError` do #ifdef mingw32_HOST_OS isReparsePoint <$> Win32.getFileAttributes path where isReparsePoint attr = attr .&. win32_fILE_ATTRIBUTE_REPARSE_POINT /= 0 #else Posix.isSymbolicLink <$> Posix.getSymbolicLinkStatus path #endif {-# DEPRECATED isSymbolicLink "Use 'pathIsSymbolicLink' instead" #-} isSymbolicLink :: FilePath -> IO Bool isSymbolicLink = pathIsSymbolicLink #ifdef mingw32_HOST_OS -- | Open the handle of an existing file or directory. openFileHandle :: String -> Win32.AccessMode -> IO Win32.HANDLE openFileHandle path mode = Win32.createFile path mode share Nothing Win32.oPEN_EXISTING flags Nothing where share = win32_fILE_SHARE_DELETE .|. Win32.fILE_SHARE_READ .|. Win32.fILE_SHARE_WRITE flags = Win32.fILE_ATTRIBUTE_NORMAL .|. Win32.fILE_FLAG_BACKUP_SEMANTICS -- required for directories #endif -- | Obtain the time at which the file or directory was last accessed. -- -- The operation may fail with: -- -- * 'isPermissionError' if the user is not permitted to read -- the access time; or -- -- * 'isDoesNotExistError' if the file or directory does not exist. -- -- Caveat for POSIX systems: This function returns a timestamp with sub-second -- resolution only if this package is compiled against @unix-2.6.0.0@ or later -- and the underlying filesystem supports them. -- -- @since 1.2.3.0 -- getAccessTime :: FilePath -> IO UTCTime getAccessTime = modifyIOError (`ioeAddLocation` "getAccessTime") . (fst <$>) . getFileTimes -- | Obtain the time at which the file or directory was last modified. -- -- The operation may fail with: -- -- * 'isPermissionError' if the user is not permitted to read -- the modification time; or -- -- * 'isDoesNotExistError' if the file or directory does not exist. -- -- Caveat for POSIX systems: This function returns a timestamp with sub-second -- resolution only if this package is compiled against @unix-2.6.0.0@ or later -- and the underlying filesystem supports them. -- getModificationTime :: FilePath -> IO UTCTime getModificationTime = modifyIOError (`ioeAddLocation` "getModificationTime") . (snd <$>) . getFileTimes getFileTimes :: FilePath -> IO (UTCTime, UTCTime) getFileTimes path = modifyIOError (`ioeAddLocation` "getFileTimes") . modifyIOError (`ioeSetFileName` path) $ getTimes where path' = normalise path -- handle empty paths #ifdef mingw32_HOST_OS getTimes = bracket (openFileHandle path' Win32.gENERIC_READ) Win32.closeHandle $ \ handle -> alloca $ \ atime -> alloca $ \ mtime -> do Win32.failIf_ not "" $ Win32.c_GetFileTime handle nullPtr atime mtime ((,) `on` posixSecondsToUTCTime . windowsToPosixTime) <$> peek atime <*> peek mtime #else getTimes = fileTimesFromStatus <$> Posix.getFileStatus path' #endif #ifndef mingw32_HOST_OS fileTimesFromStatus :: Posix.FileStatus -> (UTCTime, UTCTime) fileTimesFromStatus st = # if MIN_VERSION_unix(2, 6, 0) ( posixSecondsToUTCTime (Posix.accessTimeHiRes st) , posixSecondsToUTCTime (Posix.modificationTimeHiRes st) ) # else ( posixSecondsToUTCTime (realToFrac (Posix.accessTime st)) , posixSecondsToUTCTime (realToFrac (Posix.modificationTime st)) ) # endif #endif -- | Change the time at which the file or directory was last accessed. -- -- The operation may fail with: -- -- * 'isPermissionError' if the user is not permitted to alter the -- access time; or -- -- * 'isDoesNotExistError' if the file or directory does not exist. -- -- Some caveats for POSIX systems: -- -- * Not all systems support @utimensat@, in which case the function can only -- emulate the behavior by reading the modification time and then setting -- both the access and modification times together. On systems where -- @utimensat@ is supported, the access time is set atomically with -- nanosecond precision. -- -- * If compiled against a version of @unix@ prior to @2.7.0.0@, the function -- would not be able to set timestamps with sub-second resolution. In this -- case, there would also be loss of precision in the modification time. -- -- @since 1.2.3.0 -- setAccessTime :: FilePath -> UTCTime -> IO () setAccessTime path atime = modifyIOError (`ioeAddLocation` "setAccessTime") $ setFileTimes path (Just atime, Nothing) -- | Change the time at which the file or directory was last modified. -- -- The operation may fail with: -- -- * 'isPermissionError' if the user is not permitted to alter the -- modification time; or -- -- * 'isDoesNotExistError' if the file or directory does not exist. -- -- Some caveats for POSIX systems: -- -- * Not all systems support @utimensat@, in which case the function can only -- emulate the behavior by reading the access time and then setting both the -- access and modification times together. On systems where @utimensat@ is -- supported, the modification time is set atomically with nanosecond -- precision. -- -- * If compiled against a version of @unix@ prior to @2.7.0.0@, the function -- would not be able to set timestamps with sub-second resolution. In this -- case, there would also be loss of precision in the access time. -- -- @since 1.2.3.0 -- setModificationTime :: FilePath -> UTCTime -> IO () setModificationTime path mtime = modifyIOError (`ioeAddLocation` "setModificationTime") $ setFileTimes path (Nothing, Just mtime) setFileTimes :: FilePath -> (Maybe UTCTime, Maybe UTCTime) -> IO () setFileTimes _ (Nothing, Nothing) = return () setFileTimes path (atime, mtime) = modifyIOError (`ioeAddLocation` "setFileTimes") . modifyIOError (`ioeSetFileName` path) $ setTimes (utcTimeToPOSIXSeconds <$> atime, utcTimeToPOSIXSeconds <$> mtime) where path' = normalise path -- handle empty paths setTimes :: (Maybe POSIXTime, Maybe POSIXTime) -> IO () #ifdef mingw32_HOST_OS setTimes (atime', mtime') = bracket (openFileHandle path' Win32.gENERIC_WRITE) Win32.closeHandle $ \ handle -> maybeWith with (posixToWindowsTime <$> atime') $ \ atime'' -> maybeWith with (posixToWindowsTime <$> mtime') $ \ mtime'' -> Win32.failIf_ not "" $ Win32.c_SetFileTime handle nullPtr atime'' mtime'' #elif defined HAVE_UTIMENSAT setTimes (atime', mtime') = withFilePath path' $ \ path'' -> withArray [ maybe utimeOmit toCTimeSpec atime' , maybe utimeOmit toCTimeSpec mtime' ] $ \ times -> throwErrnoPathIfMinus1_ "" path' $ c_utimensat c_AT_FDCWD path'' times 0 #else setTimes (Just atime', Just mtime') = setFileTimes' path' atime' mtime' setTimes (atime', mtime') = do (atimeOld, mtimeOld) <- fileTimesFromStatus <$> Posix.getFileStatus path' setFileTimes' path' (fromMaybe (utcTimeToPOSIXSeconds atimeOld) atime') (fromMaybe (utcTimeToPOSIXSeconds mtimeOld) mtime') setFileTimes' :: FilePath -> POSIXTime -> POSIXTime -> IO () # if MIN_VERSION_unix(2, 7, 0) setFileTimes' = Posix.setFileTimesHiRes # else setFileTimes' pth atime' mtime' = Posix.setFileTimes pth (fromInteger (truncate atime')) (fromInteger (truncate mtime')) # endif #endif #ifdef mingw32_HOST_OS -- | Difference between the Windows and POSIX epochs in units of 100ns. windowsPosixEpochDifference :: Num a => a windowsPosixEpochDifference = 116444736000000000 -- | Convert from Windows time to POSIX time. windowsToPosixTime :: Win32.FILETIME -> POSIXTime windowsToPosixTime (Win32.FILETIME t) = (fromIntegral t - windowsPosixEpochDifference) / 10000000 -- | Convert from POSIX time to Windows time. This is lossy as Windows time -- has a resolution of only 100ns. posixToWindowsTime :: POSIXTime -> Win32.FILETIME posixToWindowsTime t = Win32.FILETIME $ truncate (t * 10000000 + windowsPosixEpochDifference) #endif #ifdef mingw32_HOST_OS withFileStatus :: String -> FilePath -> (Ptr CStat -> IO a) -> IO a withFileStatus loc name f = do modifyIOError (`ioeSetFileName` name) $ allocaBytes sizeof_stat $ \p -> withFilePath (fileNameEndClean name) $ \s -> do throwErrnoIfMinus1Retry_ loc (c_stat s p) f p isDirectory :: Ptr CStat -> IO Bool isDirectory stat = do mode <- st_mode stat return (s_isdir mode) fileNameEndClean :: String -> String fileNameEndClean name = if isDrive name then addTrailingPathSeparator name else dropTrailingPathSeparator name #endif {- | Returns the current user's home directory. The directory returned is expected to be writable by the current user, but note that it isn't generally considered good practice to store application-specific data here; use 'getXdgDirectory' or 'getAppUserDataDirectory' instead. On Unix, 'getHomeDirectory' returns the value of the @HOME@ environment variable. On Windows, the system is queried for a suitable path; a typical path might be @C:\/Users\//\<user\>/@. The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of home directory. * 'isDoesNotExistError' The home directory for the current user does not exist, or cannot be found. -} getHomeDirectory :: IO FilePath getHomeDirectory = modifyIOError (`ioeAddLocation` "getHomeDirectory") get where #if defined(mingw32_HOST_OS) get = getFolderPath Win32.cSIDL_PROFILE `catchIOError` \ _ -> getFolderPath Win32.cSIDL_WINDOWS getFolderPath what = Win32.sHGetFolderPath nullPtr what nullPtr 0 #else get = getEnv "HOME" #endif -- | Special directories for storing user-specific application data, -- configuration, and cache files, as specified by the -- <http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html XDG Base Directory Specification>. -- -- Note: On Windows, 'XdgData' and 'XdgConfig' map to the same directory. -- -- @since 1.2.3.0 data XdgDirectory = XdgData -- ^ For data files (e.g. images). -- Defaults to @~\/.local\/share@ and can be -- overridden by the @XDG_DATA_HOME@ environment variable. -- On Windows, it is @%APPDATA%@ -- (e.g. @C:\/Users\//\<user\>/\/AppData\/Roaming@). -- Can be considered as the user-specific equivalent of @\/usr\/share@. | XdgConfig -- ^ For configuration files. -- Defaults to @~\/.config@ and can be -- overridden by the @XDG_CONFIG_HOME@ environment variable. -- On Windows, it is @%APPDATA%@ -- (e.g. @C:\/Users\//\<user\>/\/AppData\/Roaming@). -- Can be considered as the user-specific equivalent of @\/etc@. | XdgCache -- ^ For non-essential files (e.g. cache). -- Defaults to @~\/.cache@ and can be -- overridden by the @XDG_CACHE_HOME@ environment variable. -- On Windows, it is @%LOCALAPPDATA%@ -- (e.g. @C:\/Users\//\<user\>/\/AppData\/Local@). -- Can be considered as the user-specific equivalent of @\/var\/cache@. deriving (Bounded, Enum, Eq, Ord, Read, Show) -- | Obtain the paths to special directories for storing user-specific -- application data, configuration, and cache files, conforming to the -- <http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html XDG Base Directory Specification>. -- Compared with 'getAppUserDataDirectory', this function provides a more -- fine-grained hierarchy as well as greater flexibility for the user. -- -- It also works on Windows, although in that case 'XdgData' and 'XdgConfig' -- will map to the same directory. -- -- The second argument is usually the name of the application. Since it -- will be integrated into the path, it must consist of valid path -- characters. -- -- Note: The directory may not actually exist, in which case you would need -- to create it with file mode @700@ (i.e. only accessible by the owner). -- -- @since 1.2.3.0 getXdgDirectory :: XdgDirectory -- ^ which special directory -> FilePath -- ^ a relative path that is appended -- to the path; if empty, the base -- path is returned -> IO FilePath getXdgDirectory xdgDir suffix = modifyIOError (`ioeAddLocation` "getXdgDirectory") $ normalise . (</> suffix) <$> case xdgDir of XdgData -> get False "XDG_DATA_HOME" ".local/share" XdgConfig -> get False "XDG_CONFIG_HOME" ".config" XdgCache -> get True "XDG_CACHE_HOME" ".cache" where #if defined(mingw32_HOST_OS) get isLocal _ _ = Win32.sHGetFolderPath nullPtr which nullPtr 0 where which | isLocal = win32_cSIDL_LOCAL_APPDATA | otherwise = Win32.cSIDL_APPDATA #else get _ name fallback = do env <- lookupEnv name case env of Nothing -> fallback' Just path | isRelative path -> fallback' | otherwise -> return path where fallback' = (</> fallback) <$> getHomeDirectory -- | Return the value of an environment variable, or 'Nothing' if there is no -- such value. (Equivalent to "lookupEnv" from base-4.6.) lookupEnv :: String -> IO (Maybe String) lookupEnv name = do env <- tryIOErrorType isDoesNotExistError (getEnv name) case env of Left _ -> return Nothing Right value -> return (Just value) #endif -- | Similar to 'try' but only catches a specify kind of 'IOError' as -- specified by the predicate. tryIOErrorType :: (IOError -> Bool) -> IO a -> IO (Either IOError a) tryIOErrorType check action = do result <- tryIOError action case result of Left err -> if check err then return (Left err) else ioError err Right val -> return (Right val) specializeErrorString :: String -> (IOError -> Bool) -> IO a -> IO a specializeErrorString str errType action = do mx <- tryIOErrorType errType action case mx of Left e -> ioError (ioeSetErrorString e str) Right x -> return x -- | Obtain the path to a special directory for storing user-specific -- application data (traditional Unix location). Newer applications may -- prefer the the XDG-conformant location provided by 'getXdgDirectory' -- (<https://github.com/haskell/directory/issues/6#issuecomment-96521020 migration guide>). -- -- The argument is usually the name of the application. Since it will be -- integrated into the path, it must consist of valid path characters. -- -- * On Unix-like systems, the path is @~\/./\<app\>/@. -- * On Windows, the path is @%APPDATA%\//\<app\>/@ -- (e.g. @C:\/Users\//\<user\>/\/AppData\/Roaming\//\<app\>/@) -- -- Note: the directory may not actually exist, in which case you would need -- to create it. It is expected that the parent directory exists and is -- writable. -- -- The operation may fail with: -- -- * 'UnsupportedOperation' -- The operating system has no notion of application-specific data -- directory. -- -- * 'isDoesNotExistError' -- The home directory for the current user does not exist, or cannot be -- found. -- getAppUserDataDirectory :: FilePath -- ^ a relative path that is appended -- to the path -> IO FilePath getAppUserDataDirectory appName = do modifyIOError (`ioeAddLocation` "getAppUserDataDirectory") $ do #if defined(mingw32_HOST_OS) s <- Win32.sHGetFolderPath nullPtr Win32.cSIDL_APPDATA nullPtr 0 return (s++'\\':appName) #else path <- getEnv "HOME" return (path++'/':'.':appName) #endif {- | Returns the current user's document directory. The directory returned is expected to be writable by the current user, but note that it isn't generally considered good practice to store application-specific data here; use 'getXdgDirectory' or 'getAppUserDataDirectory' instead. On Unix, 'getUserDocumentsDirectory' returns the value of the @HOME@ environment variable. On Windows, the system is queried for a suitable path; a typical path might be @C:\/Users\//\<user\>/\/Documents@. The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of document directory. * 'isDoesNotExistError' The document directory for the current user does not exist, or cannot be found. -} getUserDocumentsDirectory :: IO FilePath getUserDocumentsDirectory = do modifyIOError (`ioeAddLocation` "getUserDocumentsDirectory") $ do #if defined(mingw32_HOST_OS) Win32.sHGetFolderPath nullPtr Win32.cSIDL_PERSONAL nullPtr 0 #else getEnv "HOME" #endif {- | Returns the current directory for temporary files. On Unix, 'getTemporaryDirectory' returns the value of the @TMPDIR@ environment variable or \"\/tmp\" if the variable isn\'t defined. On Windows, the function checks for the existence of environment variables in the following order and uses the first path found: * TMP environment variable. * TEMP environment variable. * USERPROFILE environment variable. * The Windows directory The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of temporary directory. The function doesn\'t verify whether the path exists. -} getTemporaryDirectory :: IO FilePath getTemporaryDirectory = #if defined(mingw32_HOST_OS) Win32.getTemporaryDirectory #else getEnv "TMPDIR" `catchIOError` \ err -> if isDoesNotExistError err then return "/tmp" else ioError err #endif ioeAddLocation :: IOError -> String -> IOError ioeAddLocation e loc = do ioeSetLocation e newLoc where newLoc = loc <> if null oldLoc then "" else ":" <> oldLoc oldLoc = ioeGetLocation e