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{-# LANGUAGE CPP #-}
{-|
This module makes the operations exported by @System.Posix.Files@
available on all platforms. On POSIX systems it re-exports operations from
@System.Posix.Files@. On other platforms it emulates the operations as far
as possible.
/NOTE: the portable implementations are not well tested, in some cases
functions are only stubs./
-}
module System.PosixCompat.Files (
-- * File modes
-- FileMode exported by System.Posix.Types
unionFileModes
, intersectFileModes
, nullFileMode
, ownerReadMode
, ownerWriteMode
, ownerExecuteMode
, ownerModes
, groupReadMode
, groupWriteMode
, groupExecuteMode
, groupModes
, otherReadMode
, otherWriteMode
, otherExecuteMode
, otherModes
, setUserIDMode
, setGroupIDMode
, stdFileMode
, accessModes
-- ** Setting file modes
, setFileMode
, setFdMode
, setFileCreationMask
-- ** Checking file existence and permissions
, fileAccess
, fileExist
-- * File status
, FileStatus
-- ** Obtaining file status
, getFileStatus
, getFdStatus
, getSymbolicLinkStatus
-- ** Querying file status
, deviceID
, fileID
, fileMode
, linkCount
, fileOwner
, fileGroup
, specialDeviceID
, fileSize
, accessTime
, modificationTime
, statusChangeTime
, isBlockDevice
, isCharacterDevice
, isNamedPipe
, isRegularFile
, isDirectory
, isSymbolicLink
, isSocket
-- * Creation
, createNamedPipe
, createDevice
-- * Hard links
, createLink
, removeLink
-- * Symbolic links
, createSymbolicLink
, readSymbolicLink
-- * Renaming files
, rename
-- * Changing file ownership
, setOwnerAndGroup
, setFdOwnerAndGroup
, setSymbolicLinkOwnerAndGroup
-- * Changing file timestamps
, setFileTimes
, touchFile
-- * Setting file sizes
, setFileSize
, setFdSize
-- * Find system-specific limits for a file
, PathVar(..)
, getPathVar
, getFdPathVar
) where
#ifndef mingw32_HOST_OS
#include "HsUnixCompat.h"
import System.Posix.Files
#if NEED_setSymbolicLinkOwnerAndGroup
import System.PosixCompat.Types
setSymbolicLinkOwnerAndGroup :: FilePath -> UserID -> GroupID -> IO ()
setSymbolicLinkOwnerAndGroup _ _ _ = return ()
#endif
#else /* Portable implementation */
import Control.Exception (bracket)
import Control.Monad (liftM, liftM2)
import Data.Bits ((.|.), (.&.))
import Prelude hiding (read)
import System.Directory (Permissions, emptyPermissions)
import System.Directory (getPermissions, setPermissions)
import System.Directory (readable, setOwnerReadable)
import System.Directory (writable, setOwnerWritable)
import System.Directory (executable, setOwnerExecutable)
import System.Directory (searchable, setOwnerSearchable)
import System.Directory (doesFileExist, doesDirectoryExist)
import System.Directory (getModificationTime, renameFile)
import System.IO (IOMode(..), openFile, hFileSize, hSetFileSize, hClose)
import System.IO.Error
import System.PosixCompat.Types
import System.Win32.File hiding (getFileType)
import System.PosixCompat.Internal.Time (
getClockTime, clockTimeToEpochTime
, modificationTimeToEpochTime
)
#ifdef __GLASGOW_HASKELL__
import GHC.IO.Handle.FD (fdToHandle)
#endif
unsupported :: String -> IO a
unsupported f = ioError $ mkIOError illegalOperationErrorType x Nothing Nothing
where
x = "System.PosixCompat.Files." ++ f ++ ": not supported"
-- -----------------------------------------------------------------------------
-- POSIX file modes
nullFileMode :: FileMode
nullFileMode = 0o000000
ownerReadMode :: FileMode
ownerWriteMode :: FileMode
ownerExecuteMode :: FileMode
groupReadMode :: FileMode
groupWriteMode :: FileMode
groupExecuteMode :: FileMode
otherReadMode :: FileMode
otherWriteMode :: FileMode
otherExecuteMode :: FileMode
setUserIDMode :: FileMode
setGroupIDMode :: FileMode
ownerReadMode = 0o000400
ownerWriteMode = 0o000200
ownerExecuteMode = 0o000100
groupReadMode = 0o000040
groupWriteMode = 0o000020
groupExecuteMode = 0o000010
otherReadMode = 0o000004
otherWriteMode = 0o000002
otherExecuteMode = 0o000001
setUserIDMode = 0o004000
setGroupIDMode = 0o002000
stdFileMode :: FileMode
ownerModes :: FileMode
groupModes :: FileMode
otherModes :: FileMode
accessModes :: FileMode
stdFileMode = ownerReadMode .|. ownerWriteMode .|.
groupReadMode .|. groupWriteMode .|.
otherReadMode .|. otherWriteMode
ownerModes = ownerReadMode .|. ownerWriteMode .|. ownerExecuteMode
groupModes = groupReadMode .|. groupWriteMode .|. groupExecuteMode
otherModes = otherReadMode .|. otherWriteMode .|. otherExecuteMode
accessModes = ownerModes .|. groupModes .|. otherModes
unionFileModes :: FileMode -> FileMode -> FileMode
unionFileModes m1 m2 = m1 .|. m2
intersectFileModes :: FileMode -> FileMode -> FileMode
intersectFileModes m1 m2 = m1 .&. m2
fileTypeModes :: FileMode
fileTypeModes = 0o0170000
blockSpecialMode :: FileMode
characterSpecialMode :: FileMode
namedPipeMode :: FileMode
regularFileMode :: FileMode
directoryMode :: FileMode
symbolicLinkMode :: FileMode
socketMode :: FileMode
blockSpecialMode = 0o0060000
characterSpecialMode = 0o0020000
namedPipeMode = 0o0010000
regularFileMode = 0o0100000
directoryMode = 0o0040000
symbolicLinkMode = 0o0120000
socketMode = 0o0140000
setFileMode :: FilePath -> FileMode -> IO ()
setFileMode name m = setPermissions name $ modeToPerms m
setFdMode :: Fd -> FileMode -> IO ()
setFdMode _ _ = unsupported "setFdMode"
-- | The portable implementation does nothing and returns 'nullFileMode'.
setFileCreationMask :: FileMode -> IO FileMode
setFileCreationMask _ = return nullFileMode
modeToPerms :: FileMode -> Permissions
#ifdef DIRECTORY_1_0
modeToPerms m = Permissions
{ readable = m .&. ownerReadMode /= 0
, writable = m .&. ownerWriteMode /= 0
, executable = m .&. ownerExecuteMode /= 0
, searchable = m .&. ownerExecuteMode /= 0 }
#else
modeToPerms m =
setOwnerReadable (m .&. ownerReadMode /= 0) $
setOwnerWritable (m .&. ownerWriteMode /= 0) $
setOwnerExecutable (m .&. ownerExecuteMode /= 0) $
setOwnerSearchable (m .&. ownerExecuteMode /= 0) $
emptyPermissions
#endif
-- -----------------------------------------------------------------------------
-- access()
fileAccess :: FilePath -> Bool -> Bool -> Bool -> IO Bool
fileAccess name read write exec =
do perm <- getPermissions name
return $ (not read || readable perm)
&& (not write || writable perm)
&& (not exec || executable perm || searchable perm)
fileExist :: FilePath -> IO Bool
fileExist name = liftM2 (||) (doesFileExist name) (doesDirectoryExist name)
-- -----------------------------------------------------------------------------
-- stat() support
data FileStatus = FileStatus
{ deviceID :: DeviceID
, fileID :: FileID
, fileMode :: FileMode
, linkCount :: LinkCount
, fileOwner :: UserID
, fileGroup :: GroupID
, specialDeviceID :: DeviceID
, fileSize :: FileOffset
, accessTime :: EpochTime
, modificationTime :: EpochTime
, statusChangeTime :: EpochTime
}
isBlockDevice :: FileStatus -> Bool
isBlockDevice stat =
(fileMode stat `intersectFileModes` fileTypeModes) == blockSpecialMode
isCharacterDevice :: FileStatus -> Bool
isCharacterDevice stat =
(fileMode stat `intersectFileModes` fileTypeModes) == characterSpecialMode
isNamedPipe :: FileStatus -> Bool
isNamedPipe stat =
(fileMode stat `intersectFileModes` fileTypeModes) == namedPipeMode
isRegularFile :: FileStatus -> Bool
isRegularFile stat =
(fileMode stat `intersectFileModes` fileTypeModes) == regularFileMode
isDirectory :: FileStatus -> Bool
isDirectory stat =
(fileMode stat `intersectFileModes` fileTypeModes) == directoryMode
isSymbolicLink :: FileStatus -> Bool
isSymbolicLink stat =
(fileMode stat `intersectFileModes` fileTypeModes) == symbolicLinkMode
isSocket :: FileStatus -> Bool
isSocket stat =
(fileMode stat `intersectFileModes` fileTypeModes) == socketMode
getFileStatus :: FilePath -> IO FileStatus
getFileStatus path = do
perm <- liftM permsToMode (getPermissions path)
typ <- getFileType path
size <- if typ == regularFileMode then getFileSize path else return 0
mtime <- liftM modificationTimeToEpochTime (getModificationTime path)
info <- bracket openPath closeHandle getFileInformationByHandle
return $ FileStatus
{ deviceID = fromIntegral (bhfiVolumeSerialNumber info)
, fileID = fromIntegral (bhfiFileIndex info)
, fileMode = typ .|. perm
, linkCount = fromIntegral (bhfiNumberOfLinks info)
, fileOwner = 0
, fileGroup = 0
, specialDeviceID = 0
, fileSize = size
, accessTime = mtime
, modificationTime = mtime
, statusChangeTime = mtime }
where
openPath = createFile path
gENERIC_READ
(fILE_SHARE_READ .|. fILE_SHARE_WRITE .|. fILE_SHARE_DELETE)
Nothing
oPEN_EXISTING
(sECURITY_ANONYMOUS .|. fILE_FLAG_BACKUP_SEMANTICS)
Nothing
permsToMode :: Permissions -> FileMode
permsToMode perms = r .|. w .|. x
where
r = f (readable perms) (ownerReadMode .|. groupReadMode .|. otherReadMode)
w = f (writable perms) (ownerWriteMode .|. groupWriteMode .|. otherWriteMode)
x = f (executable perms || searchable perms)
(ownerExecuteMode .|. groupExecuteMode .|. otherExecuteMode)
f True m = m
f False _ = nullFileMode
getFileType :: FilePath -> IO FileMode
getFileType path =
do f <- doesFileExist path
if f then return regularFileMode
else do d <- doesDirectoryExist path
if d then return directoryMode
else unsupported "Unknown file type."
getFileSize :: FilePath -> IO FileOffset
getFileSize path =
bracket (openFile path ReadMode) hClose (liftM fromIntegral . hFileSize)
getFdStatus :: Fd -> IO FileStatus
getFdStatus _ = unsupported "getFdStatus"
getSymbolicLinkStatus :: FilePath -> IO FileStatus
getSymbolicLinkStatus path = getFileStatus path
createNamedPipe :: FilePath -> FileMode -> IO ()
createNamedPipe _ _ = unsupported "createNamedPipe"
createDevice :: FilePath -> FileMode -> DeviceID -> IO ()
createDevice _ _ _ = unsupported "createDevice"
-- -----------------------------------------------------------------------------
-- Hard links
createLink :: FilePath -> FilePath -> IO ()
createLink _ _ = unsupported "createLink"
removeLink :: FilePath -> IO ()
removeLink _ = unsupported "removeLink"
-- -----------------------------------------------------------------------------
-- Symbolic Links
createSymbolicLink :: FilePath -> FilePath -> IO ()
createSymbolicLink _ _ = unsupported "createSymbolicLink"
readSymbolicLink :: FilePath -> IO FilePath
readSymbolicLink _ = unsupported "readSymbolicLink"
-- -----------------------------------------------------------------------------
-- Renaming files
rename :: FilePath -> FilePath -> IO ()
rename name1 name2 = renameFile name1 name2
-- -----------------------------------------------------------------------------
-- chown()
-- | The portable implementation does nothing.
setOwnerAndGroup :: FilePath -> UserID -> GroupID -> IO ()
setOwnerAndGroup _ _ _ = return ()
-- | The portable implementation does nothing.
setFdOwnerAndGroup :: Fd -> UserID -> GroupID -> IO ()
setFdOwnerAndGroup _ _ _ = return ()
-- | The portable implementation does nothing.
setSymbolicLinkOwnerAndGroup :: FilePath -> UserID -> GroupID -> IO ()
setSymbolicLinkOwnerAndGroup _ _ _ = return ()
-- -----------------------------------------------------------------------------
-- utime()
setFileTimes :: FilePath -> EpochTime -> EpochTime -> IO ()
setFileTimes _ _ _ = unsupported "setFileTimes"
touchFile :: FilePath -> IO ()
touchFile name =
do t <- liftM clockTimeToEpochTime getClockTime
setFileTimes name t t
-- -----------------------------------------------------------------------------
-- Setting file sizes
setFileSize :: FilePath -> FileOffset -> IO ()
setFileSize file off =
bracket (openFile file WriteMode) (hClose)
(\h -> hSetFileSize h (fromIntegral off))
setFdSize :: Fd -> FileOffset -> IO ()
#ifdef __GLASGOW_HASKELL__
setFdSize (Fd fd) off =
do h <- fdToHandle (fromIntegral fd)
hSetFileSize h (fromIntegral off)
#else
setFdSize fd off = unsupported "setFdSize"
#endif
-- -----------------------------------------------------------------------------
-- pathconf()/fpathconf() support
data PathVar
= FileSizeBits -- _PC_FILESIZEBITS
| LinkLimit -- _PC_LINK_MAX
| InputLineLimit -- _PC_MAX_CANON
| InputQueueLimit -- _PC_MAX_INPUT
| FileNameLimit -- _PC_NAME_MAX
| PathNameLimit -- _PC_PATH_MAX
| PipeBufferLimit -- _PC_PIPE_BUF
-- These are described as optional in POSIX:
-- _PC_ALLOC_SIZE_MIN
-- _PC_REC_INCR_XFER_SIZE
-- _PC_REC_MAX_XFER_SIZE
-- _PC_REC_MIN_XFER_SIZE
-- _PC_REC_XFER_ALIGN
| SymbolicLinkLimit -- _PC_SYMLINK_MAX
| SetOwnerAndGroupIsRestricted -- _PC_CHOWN_RESTRICTED
| FileNamesAreNotTruncated -- _PC_NO_TRUNC
| VDisableChar -- _PC_VDISABLE
| AsyncIOAvailable -- _PC_ASYNC_IO
| PrioIOAvailable -- _PC_PRIO_IO
| SyncIOAvailable -- _PC_SYNC_IO
getPathVar :: FilePath -> PathVar -> IO Limit
getPathVar _ _ = unsupported "getPathVar"
getFdPathVar :: Fd -> PathVar -> IO Limit
getFdPathVar _ _ = unsupported "getFdPathVar"
#endif