-----------------------------------------------------------------------------
-- |
-- Module : System.Posix.HFuse
-- Copyright : (c) Jérémy Bobbio
-- License : BSD-style
--
-- Maintainer : jeremy.bobbio@etu.upmc.fr
-- Stability : experimental
-- Portability : GHC 6.8
--
-- HFuse is a binding for the FUSE (Filesystem in USErspace) library.
--
-- See
--
-- This library allow new filesystem implementation as simple user-land
-- programs.
--
-- The binding tries to follow as much as possible current Haskell POSIX
-- interface in "System.Posix.Files" and "System.Posix.Directory".
--
-- FUSE uses POSIX thread, thus Haskell implementation needs to be linked
-- against a threaded runtime system (eg. using the @threaded@ GHC option).
--
-----------------------------------------------------------------------------
module System.Posix.HFuse
( -- * Using FUSE
-- $intro
module Foreign.C.Error
, FuseOperations(..)
, defaultFuseOps
, fuseMain -- :: FuseOperations -> (Exception -> IO Errno) -> IO ()
, defaultExceptionHandler -- :: Exception -> IO Errno
-- * Operations datatypes
, FileStat(..)
, EntryType(..)
, FileSystemStats(..)
, SyncType(..)
-- * FUSE Context
, getFuseContext -- :: IO FuseContext
, FuseContext(fuseCtxUserID, fuseCtxGroupID, fuseCtxProcessID)
-- * File modes
, entryTypeToFileMode -- :: EntryType -> FileMode
, OpenMode(..)
, OpenFileFlags(..)
, intersectFileModes -- :: FileMode
, unionFileModes -- :: FileMode
) where
import Prelude hiding ( Read )
import Control.Exception ( Exception, handle )
import Foreign
import Foreign.C
import Foreign.C.Error
import Foreign.Marshal
import System.Environment ( getProgName, getArgs )
import System.IO ( hPutStrLn, stderr )
import System.Posix.Types
import System.Posix.Files ( accessModes, intersectFileModes, unionFileModes )
import System.Posix.IO ( OpenMode(..), OpenFileFlags(..) )
-- TODO: FileMode -> Permissions
-- TODO: Arguments !
-- TODO: implement binding to fuse_invalidate
-- TODO: bind fuse_*xattr
#define FUSE_USE_VERSION 22
#include
#include
#include
#include
{- $intro
'FuseOperations' contains a field for each filesystem operations that can be called
by FUSE. Think like if you were implementing a file system inside the Linux kernel.
Each actions must return a POSIX error code, also called 'Errno' reflecting
operation relult. For actions not using 'Either', you should return 'eOK' in case
of success.
Read and writes are done with Haskell 'String' type. Even if this representation
is known to have drawbacks, the binding try to be coherent with current
Haskell libraries.
-}
{- All operations should return the negated error value (-errno) on
error.
-}
-- | Used by 'fuseGetFileStat'.
data FileStat = FileStat { statEntryType :: EntryType
, statFileMode :: FileMode
, statLinkCount :: LinkCount
, statFileOwner :: UserID
, statFileGroup :: GroupID
, statSpecialDeviceID :: DeviceID
, statFileSize :: FileOffset
, statBlocks :: Integer
, statAccessTime :: EpochTime
, statModificationTime :: EpochTime
, statStatusChangeTime :: EpochTime
}
{- getattr() doesn't need to fill in the following fields:
st_ino
st_dev
st_blksize
-}
{- readlink() should fill the buffer with a null terminated string. The
buffer size argument includes the space for the terminating null
character. If the linkname is too long to fit in the buffer, it should
be truncated. The return value should be 0 for success.
-}
-- | Used by 'fuseGetDirectoryContents' implementation to specify the type of
-- a directory entry.
data EntryType
= Unknown -- ^ Unknown entry type
| NamedPipe
| CharacterSpecial
| Directory
| BlockSpecial
| RegularFile
| SymbolicLink
| Socket
entryTypeToDT :: EntryType -> Int
entryTypeToDT Unknown = (#const DT_UNKNOWN)
entryTypeToDT NamedPipe = (#const DT_FIFO)
entryTypeToDT CharacterSpecial = (#const DT_CHR)
entryTypeToDT Directory = (#const DT_DIR)
entryTypeToDT BlockSpecial = (#const DT_BLK)
entryTypeToDT RegularFile = (#const DT_REG)
entryTypeToDT SymbolicLink = (#const DT_LNK)
entryTypeToDT Socket = (#const DT_SOCK)
fileTypeModes :: FileMode
fileTypeModes = (#const S_IFMT)
blockSpecialMode :: FileMode
blockSpecialMode = (#const S_IFBLK)
characterSpecialMode :: FileMode
characterSpecialMode = (#const S_IFCHR)
namedPipeMode :: FileMode
namedPipeMode = (#const S_IFIFO)
regularFileMode :: FileMode
regularFileMode = (#const S_IFREG)
directoryMode :: FileMode
directoryMode = (#const S_IFDIR)
symbolicLinkMode :: FileMode
symbolicLinkMode = (#const S_IFLNK)
socketMode :: FileMode
socketMode = (#const S_IFSOCK)
-- | Converts an 'EntryType' into the corresponding POSIX 'FileMode'.
entryTypeToFileMode :: EntryType -> FileMode
entryTypeToFileMode Unknown = 0
entryTypeToFileMode NamedPipe = namedPipeMode
entryTypeToFileMode CharacterSpecial = characterSpecialMode
entryTypeToFileMode Directory = directoryMode
entryTypeToFileMode BlockSpecial = blockSpecialMode
entryTypeToFileMode RegularFile = regularFileMode
entryTypeToFileMode SymbolicLink = symbolicLinkMode
entryTypeToFileMode Socket = socketMode
fileModeToEntryType :: FileMode -> EntryType
fileModeToEntryType mode
| fileType == namedPipeMode = NamedPipe
| fileType == characterSpecialMode = CharacterSpecial
| fileType == directoryMode = Directory
| fileType == blockSpecialMode = BlockSpecial
| fileType == regularFileMode = RegularFile
| fileType == symbolicLinkMode = SymbolicLink
| fileType == socketMode = Socket
where fileType = mode .&. (#const S_IFMT)
{- getdir() is the opendir(), readdir(), ..., closedir() sequence
in one call. For each directory entry the filldir parameter should
be called.
-}
{-
There is no create() operation, mknod() will be called for
creation of all non directory, non symlink nodes.
-}
{- open() should not return a filehandle, but 0 on success. No
creation, or trunctation flags (O_CREAT, O_EXCL, O_TRUNC) will be
passed to open(). Open should only check if the operation is
permitted for the given flags.
-}
{- read(), write() are not passed a filehandle, but rather a
pathname. The offset of the read and write is passed as the last
argument, like the pread() and pwrite() system calls. (NOTE:
read() should always return the number of bytes requested, except
at end of file)
TODO: String type was used to mimic System.Posix.IO but it should change
after inclusion of better I/O system in Haskell libraries.
-}
-- | Type used by the 'fuseGetFileSystemStats'.
data FileSystemStats = FileSystemStats
{ fsStatBlockSize :: Integer
-- ^ Optimal transfer block size. FUSE default is 512.
, fsStatBlockCount :: Integer
-- ^ Total data blocks in file system.
, fsStatBlocksFree :: Integer
-- ^ Free blocks in file system.
, fsStatBlocksAvailable :: Integer
-- ^ Free blocks available to non-superusers.
, fsStatFileCount :: Integer
-- ^ Total file nodes in file system.
, fsStatFilesFree :: Integer
-- ^ Free file nodes in file system.
, fsStatMaxNameLength :: Integer
-- ^ Maximum length of filenames. FUSE default is 255.
}
{- release() is called when an open file has:
1) all file descriptors closed
2)
all memory mappings unmapped
This call need only be implemented if this information is required,
otherwise set this function to NULL.
TODO: Find out what these "flags" are (Int here).
-}
-- | Used by 'fuseSynchronizeFile'.
data SyncType
= FullSync
-- ^ Synchronize all in-core parts of a file to disk: file content and
-- metadata.
| DataSync
-- ^ Synchronize only the file content.
deriving (Eq, Enum)
{- fsync() has a boolean 'datasync' parameter which if TRUE then do
an fdatasync() operation.
-}
-- | Returned by 'getFuseContext'.
data FuseContext = FuseContext
{ fuseCtxUserID :: UserID
, fuseCtxGroupID :: GroupID
, fuseCtxProcessID :: ProcessID
}
-- | Returns the context of the program doing the current FUSE call.
getFuseContext :: IO FuseContext
getFuseContext =
do pCtx <- fuse_get_context
userID <- (#peek struct fuse_context, uid) pCtx
groupID <- (#peek struct fuse_context, gid) pCtx
processID <- (#peek struct fuse_context, pid) pCtx
return $ FuseContext { fuseCtxUserID = userID
, fuseCtxGroupID = groupID
, fuseCtxProcessID = processID
}
-- | This record, given to 'fuseMain', binds each required file system operations.
--
-- Each field is named against 'System.Posix' names. Matching Linux system calls
-- are also given as a reference.
--
-- * 'fuseGetFileStat' implements
-- 'System.Posix.Files.getSymbolicLinkStatus' operation (POSIX @lstat(2)@).
--
-- * 'fuseReadSymbolicLink' implements
-- 'System.Posix.Files.readSymbolicLink' operation (POSIX @readlink(2)@).
-- The returned 'FilePath' might be truncated depending on caller
-- buffer size.
--
-- * 'fuseGetDirectoryContents' implements
-- 'System.Directory.getDirectoryContents' (POSIX @readddir(2)@).
--
-- * 'fuseCreateDevice' implements 'System.Posix.Files.createDevice'
-- (POSIX @mknod(2)@).
-- This function will also be called for regular file creation.
--
-- * 'fuseCreateDirectory' implements 'System.Posix.Directory.createDirectory'
-- (POSIX @mkdir(2)@).
--
-- * 'fuseRemoveLink' implements 'System.Posix.Files.removeLink'
-- (POSIX @unlink(2)@).
--
-- * 'fuseRemoveDirectory' implements 'System.Posix.Directory.removeDirectory'
-- (POSIX @rmdir(2)@).
--
-- * 'fuseCreateSymbolicLink' implements
-- 'System.Posix.Files.createSymbolicLink' (POSIX @symlink(2)@).
--
-- * 'fuseRename' implements 'System.Posix.Files.rename' (POSIX @rename(2)@).
--
-- * 'fuseCreateLink' implements 'System.Posix.Files.createLink'
-- (POSIX @link(2)@).
--
-- * 'fuseSetFileMode' implements 'System.Posix.Files.setFileMode'
-- (POSIX @chmod(2)@).
--
-- * 'fuseSetOwnerAndGroup' implements 'System.Posix.Files.setOwnerAndGroup'
-- (POSIX @chown(2)@).
--
-- * 'fuseSetFileSize' implements 'System.Posix.Files.setFileSize'
-- (POSIX @truncate(2)@).
--
-- * 'fuseSetFileTimes' implements 'System.Posix.Files.setFileTimes'
-- (POSIX @utime(2)@).
--
-- * 'fuseOpen' implements 'System.Posix.Files.openFd'
-- (POSIX @open(2)@), but this does not actually returns a file handle
-- but 'eOK' if the operation is permitted with the given flags.
-- No creation, exclusive access or truncating flags will be passed.
--
-- * 'fuseRead' implements Unix98 @pread(2)@. It differs
-- from 'System.Posix.Files.fdRead' by the explicit 'FileOffset' argument.
--
-- * 'fuseWrite' implements Unix98 @pwrite(2)@. It differs
-- from 'System.Posix.Files.fdWrite' by the explicit 'FileOffset' argument.
--
-- * 'fuseGetFileSystemStats' implements @statfs(2)@.
--
-- * 'fuseFlush' is called when @close(2)@ has been called on an open file.
-- Note: this does not mean that the file is released. This function may be
-- called more than once for each @open(2)@. The return value is passed on
-- to the @close(2)@ system call.
--
-- * 'fuseRelease' is called when an open file has all file descriptors closed
-- and all memory mappings unmapped. For every @open@ call there will be
-- exactly one @release@ call with the same flags. It is possible to have
-- a file opened more than once, in which case only the last release will
-- mean, that no more reads or writes will happen on the file.
--
-- * 'fuseSynchronizeFile' implements @fsync(2)@.
--
data FuseOperations = FuseOperations
{ fuseGetFileStat :: FilePath -> IO (Either Errno FileStat)
, fuseReadSymbolicLink :: FilePath -> IO (Either Errno FilePath)
, fuseGetDirectoryContents :: FilePath
-> IO (Either Errno [(FilePath, EntryType)])
, fuseCreateDevice :: FilePath -> EntryType -> FileMode
-> DeviceID -> IO Errno
, fuseCreateDirectory :: FilePath -> FileMode -> IO Errno
, fuseRemoveLink :: FilePath -> IO Errno
, fuseRemoveDirectory :: FilePath -> IO Errno
, fuseCreateSymbolicLink :: FilePath -> FilePath -> IO Errno
, fuseRename :: FilePath -> FilePath -> IO Errno
, fuseCreateLink :: FilePath -> FilePath -> IO Errno
, fuseSetFileMode :: FilePath -> FileMode -> IO Errno
, fuseSetOwnerAndGroup :: FilePath -> UserID -> GroupID -> IO Errno
, fuseSetFileSize :: FilePath -> FileOffset -> IO Errno
, fuseSetFileTimes :: FilePath -> EpochTime -> EpochTime -> IO Errno
, fuseOpen :: FilePath -> OpenMode -> OpenFileFlags -> IO Errno
, fuseRead :: FilePath -> ByteCount -> FileOffset
-> IO (Either Errno (String, ByteCount))
, fuseWrite :: FilePath -> String -> FileOffset
-> IO (Either Errno ByteCount)
, fuseGetFileSystemStats :: String -> IO (Either Errno FileSystemStats)
, fuseFlush :: FilePath -> IO Errno
, fuseRelease :: FilePath -> Int -> IO ()
, fuseSynchronizeFile :: FilePath -> SyncType -> IO Errno
, fuseOpenDirectory :: FilePath -> IO Errno
, fuseReleaseDirectory :: FilePath -> IO Errno
, fuseSynchronizeDirectory :: FilePath -> SyncType -> IO Errno
, fuseInit :: IO ()
, fuseDestroy :: IO ()
}
-- |Empty / default versions of the FUSE operations.
defaultFuseOps :: FuseOperations
defaultFuseOps =
FuseOperations { fuseGetFileStat = \_ -> return (Left eNOSYS)
, fuseReadSymbolicLink = \_ -> return (Left eNOSYS)
, fuseGetDirectoryContents = \_ -> return (Left eNOSYS)
, fuseCreateDevice = \_ _ _ _ -> return eNOSYS
, fuseCreateDirectory = \_ _ -> return eNOSYS
, fuseRemoveLink = \_ -> return eNOSYS
, fuseRemoveDirectory = \_ -> return eNOSYS
, fuseCreateSymbolicLink = \_ _ -> return eNOSYS
, fuseRename = \_ _ -> return eNOSYS
, fuseCreateLink = \_ _ -> return eNOSYS
, fuseSetFileMode = \_ _ -> return eNOSYS
, fuseSetOwnerAndGroup = \_ _ _ -> return eNOSYS
, fuseSetFileSize = \_ _ -> return eNOSYS
, fuseSetFileTimes = \_ _ _ -> return eNOSYS
, fuseOpen = \_ _ _ -> return eNOSYS
, fuseRead = \_ _ _ -> return (Left eNOSYS)
, fuseWrite = \_ _ _ -> return (Left eNOSYS)
, fuseGetFileSystemStats = \_ -> return (Left eNOSYS)
, fuseFlush = \_ -> return eOK
, fuseRelease = \_ _ -> return ()
, fuseSynchronizeFile = \_ _ -> return eNOSYS
, fuseOpenDirectory = \_ -> return eNOSYS
, fuseReleaseDirectory = \_ -> return eNOSYS
, fuseSynchronizeDirectory = \_ _ -> return eNOSYS
, fuseInit = return ()
, fuseDestroy = return ()
}
-- | Main function of FUSE.
-- This is all that has to be called from the @main@ function. On top of
-- the 'FuseOperations' record with filesystem implementation, you must give
-- an exception handler converting Haskell exceptions to 'Errno'.
--
-- This function does the following:
--
-- * parses command line options (@-d@, @-s@ and @-h@) ;
--
-- * passes all options after @--@ to the fusermount program ;
--
-- * mounts the filesystem by calling @fusermount@ ;
--
-- * installs signal handlers for 'System.Posix.Signals.keyboardSignal',
-- 'System.Posix.Signals.lostConnection',
-- 'System.Posix.Signals.softwareTermination' and
-- 'System.Posix.Signals.openEndedPipe' ;
--
-- * registers an exit handler to unmount the filesystem on program exit ;
--
-- * registers the operations ;
--
-- * calls FUSE event loop.
fuseMain :: FuseOperations -> (Exception -> IO Errno) -> IO ()
fuseMain ops handler =
allocaBytes (#size struct fuse_operations) $ \ pOps -> do
mkGetAttr wrapGetAttr >>= (#poke struct fuse_operations, getattr) pOps
mkReadLink wrapReadLink >>= (#poke struct fuse_operations, readlink) pOps
-- FIXME: getdir is deprecated
mkGetDir wrapGetDir >>= (#poke struct fuse_operations, getdir) pOps
mkMkNod wrapMkNod >>= (#poke struct fuse_operations, mknod) pOps
mkMkDir wrapMkDir >>= (#poke struct fuse_operations, mkdir) pOps
mkUnlink wrapUnlink >>= (#poke struct fuse_operations, unlink) pOps
mkRmDir wrapRmDir >>= (#poke struct fuse_operations, rmdir) pOps
mkSymLink wrapSymLink >>= (#poke struct fuse_operations, symlink) pOps
mkRename wrapRename >>= (#poke struct fuse_operations, rename) pOps
mkLink wrapLink >>= (#poke struct fuse_operations, link) pOps
mkChMod wrapChMod >>= (#poke struct fuse_operations, chmod) pOps
mkChOwn wrapChOwn >>= (#poke struct fuse_operations, chown) pOps
mkTruncate wrapTruncate >>= (#poke struct fuse_operations, truncate) pOps
mkUTime wrapUTime >>= (#poke struct fuse_operations, utime) pOps
mkOpen wrapOpen >>= (#poke struct fuse_operations, open) pOps
mkRead wrapRead >>= (#poke struct fuse_operations, read) pOps
mkWrite wrapWrite >>= (#poke struct fuse_operations, write) pOps
mkStatFS wrapStatFS >>= (#poke struct fuse_operations, statfs) pOps
mkFlush wrapFlush >>= (#poke struct fuse_operations, flush) pOps
mkRelease wrapRelease >>= (#poke struct fuse_operations, release) pOps
mkFSync wrapFSync >>= (#poke struct fuse_operations, fsync) pOps
-- TODO: Implement these
(#poke struct fuse_operations, setxattr) pOps nullPtr
(#poke struct fuse_operations, getxattr) pOps nullPtr
(#poke struct fuse_operations, listxattr) pOps nullPtr
(#poke struct fuse_operations, removexattr) pOps nullPtr
mkOpenDir wrapOpenDir >>= (#poke struct fuse_operations, opendir) pOps
-- TODO: Implement mkReadDir
-- mkReadDir wrapReadDir >>= (#poke struct fuse_operations, readdir) pOps
(#poke struct fuse_operations, readdir) pOps nullPtr
mkReleaseDir wrapReleaseDir >>= (#poke struct fuse_operations, releasedir) pOps
mkFSyncDir wrapFSyncDir >>= (#poke struct fuse_operations, fsyncdir) pOps
mkInit wrapInit >>= (#poke struct fuse_operations, init) pOps
mkDestroy wrapDestroy >>= (#poke struct fuse_operations, destroy) pOps
prog <- getProgName
args <- getArgs
let allArgs = (prog:args)
argc = length allArgs
withMany withCString allArgs $ \ pAddrs ->
withArray pAddrs $ \ pArgv ->
do fuse_main_real argc pArgv pOps (#size struct fuse_operations)
where fuseHandler :: Exception -> IO CInt
fuseHandler e = handler e >>= return . unErrno
wrapGetAttr :: CGetAttr
wrapGetAttr pFilePath pStat = handle fuseHandler $
do filePath <- peekCString pFilePath
eitherFileStat <- (fuseGetFileStat ops) filePath
case eitherFileStat of
Left (Errno errno) -> return (- errno)
Right stat ->
do (#poke struct stat, st_mode) pStat
(entryTypeToFileMode (statEntryType stat)
`unionFileModes`
(statFileMode stat `intersectFileModes` accessModes))
(#poke struct stat, st_nlink) pStat (statLinkCount stat)
(#poke struct stat, st_uid) pStat (statFileOwner stat)
(#poke struct stat, st_gid) pStat (statFileGroup stat)
(#poke struct stat, st_rdev) pStat
(statSpecialDeviceID stat)
(#poke struct stat, st_size) pStat (statFileSize stat)
(#poke struct stat, st_blocks) pStat
(fromIntegral (statBlocks stat) :: (#type blkcnt_t))
(#poke struct stat, st_atime) pStat (statAccessTime stat)
(#poke struct stat, st_mtime) pStat
(statModificationTime stat)
(#poke struct stat, st_ctime) pStat
(statStatusChangeTime stat)
return okErrno
wrapReadLink :: CReadLink
wrapReadLink pFilePath pBuf bufSize = handle fuseHandler $
do filePath <- peekCString pFilePath
return (- unErrno eNOSYS)
eitherTarget <- (fuseReadSymbolicLink ops) filePath
case eitherTarget of
Left (Errno errno) -> return (- errno)
Right target ->
do pokeCStringLen0 (pBuf, (fromIntegral bufSize)) target
return okErrno
wrapGetDir :: CGetDir
wrapGetDir pFilePath pDirHandle pDirFil = handle fuseHandler $
do filePath <- peekCString pFilePath
let filler (entryFilePath, entryType) =
withCString entryFilePath $ \ pEntryFilePath ->
(mkDirFil pDirFil) pDirHandle pEntryFilePath
(entryTypeToDT entryType) >>= return . Errno
eitherContents <- (fuseGetDirectoryContents ops) filePath
case eitherContents of
Left (Errno errno) -> return (- errno)
Right contents ->
do mapM_ filler contents
return okErrno
wrapMkNod :: CMkNod
wrapMkNod pFilePath mode dev = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseCreateDevice ops) filePath
(fileModeToEntryType mode) mode dev
return (- errno)
wrapMkDir :: CMkDir
wrapMkDir pFilePath mode = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseCreateDirectory ops) filePath mode
return (- errno)
wrapUnlink :: CUnlink
wrapUnlink pFilePath = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseRemoveLink ops) filePath
return (- errno)
wrapRmDir :: CRmDir
wrapRmDir pFilePath = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseRemoveDirectory ops) filePath
return (- errno)
wrapSymLink :: CSymLink
wrapSymLink pSource pDestination = handle fuseHandler $
do source <- peekCString pSource
destination <- peekCString pDestination
(Errno errno) <- (fuseCreateSymbolicLink ops) source destination
return (- errno)
wrapRename :: CRename
wrapRename pOld pNew = handle fuseHandler $
do old <- peekCString pOld
new <- peekCString pNew
(Errno errno) <- (fuseRename ops) old new
return (- errno)
wrapLink :: CLink
wrapLink pSource pDestination = handle fuseHandler $
do source <- peekCString pSource
destination <- peekCString pDestination
(Errno errno) <- (fuseCreateLink ops) source destination
return (- errno)
wrapChMod :: CChMod
wrapChMod pFilePath mode = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseSetFileMode ops) filePath mode
return (- errno)
wrapChOwn :: CChOwn
wrapChOwn pFilePath uid gid = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseSetOwnerAndGroup ops) filePath uid gid
return (- errno)
wrapTruncate :: CTruncate
wrapTruncate pFilePath off = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseSetFileSize ops) filePath off
return (- errno)
wrapUTime :: CUTime
wrapUTime pFilePath pUTimBuf = handle fuseHandler $
do filePath <- peekCString pFilePath
accessTime <- (#peek struct utimbuf, actime) pUTimBuf
modificationTime <- (#peek struct utimbuf, modtime) pUTimBuf
(Errno errno) <- (fuseSetFileTimes ops) filePath
accessTime modificationTime
return (- errno)
wrapOpen :: COpen
wrapOpen pFilePath pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
(flags :: CInt) <- (#peek struct fuse_file_info, flags) pFuseFileInfo
let append = (#const O_APPEND) .&. flags == (#const O_APPEND)
noctty = (#const O_NOCTTY) .&. flags == (#const O_NOCTTY)
nonBlock = (#const O_NONBLOCK) .&. flags == (#const O_NONBLOCK)
how | (#const O_RDWR) .&. flags == (#const O_RDWR) = ReadWrite
| (#const O_WRONLY) .&. flags == (#const O_WRONLY) = WriteOnly
| otherwise = ReadOnly
openFileFlags = OpenFileFlags { append = append
, exclusive = False
, noctty = noctty
, nonBlock = nonBlock
, trunc = False
}
(Errno errno) <- (fuseOpen ops) filePath how openFileFlags
return (- errno)
wrapRead :: CRead
wrapRead pFilePath pBuf bufSiz off pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
eitherRead <- (fuseRead ops) filePath bufSiz off
case eitherRead of
Left (Errno errno) -> return (- errno)
Right (bytes, byteCount) ->
do pokeCStringLen (pBuf, fromIntegral byteCount) bytes
return (fromIntegral byteCount)
wrapWrite :: CWrite
wrapWrite pFilePath pBuf bufSiz off pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
buf <- peekCStringLen (pBuf, fromIntegral bufSiz)
eitherBytes <- (fuseWrite ops) filePath buf off
case eitherBytes of
Left (Errno errno) -> return (- errno)
Right bytes -> return (fromIntegral bytes)
wrapStatFS :: CStatFS
wrapStatFS pStr pStatFS = handle fuseHandler $
do str <- peekCString pStr
eitherStatFS <- (fuseGetFileSystemStats ops) str
case eitherStatFS of
Left (Errno errno) -> return (- errno)
Right stat ->
do (#poke struct statfs, f_bsize) pStatFS
(fromIntegral (fsStatBlockSize stat) :: (#type long))
(#poke struct statfs, f_blocks) pStatFS
(fromIntegral (fsStatBlockCount stat) :: (#type long))
(#poke struct statfs, f_bfree) pStatFS
(fromIntegral (fsStatBlocksFree stat) :: (#type long))
(#poke struct statfs, f_bavail) pStatFS
(fromIntegral (fsStatBlocksAvailable
stat) :: (#type long))
(#poke struct statfs, f_files) pStatFS
(fromIntegral (fsStatFileCount stat) :: (#type long))
(#poke struct statfs, f_ffree) pStatFS
(fromIntegral (fsStatFilesFree stat) :: (#type long))
(#poke struct statfs, f_namelen) pStatFS
(fromIntegral (fsStatMaxNameLength stat) :: (#type long))
return 0
wrapFlush :: CFlush
wrapFlush pFilePath pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseFlush ops) filePath
return (- errno)
wrapRelease :: CRelease
wrapRelease pFilePath pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
flags <- (#peek struct fuse_file_info, flags) pFuseFileInfo
(fuseRelease ops) filePath flags
return 0
wrapFSync :: CFSync
wrapFSync pFilePath isFullSync pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseSynchronizeFile ops)
filePath (toEnum isFullSync)
return (- errno)
wrapOpenDir :: COpenDir
wrapOpenDir pFilePath pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
-- XXX: Should we pass flags from pFuseFileInfo?
(Errno errno) <- (fuseOpenDirectory ops) filePath
return (- errno)
-- TODO: wrapReadDir
wrapReleaseDir :: CReleaseDir
wrapReleaseDir pFilePath pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseReleaseDirectory ops) filePath
return (- errno)
wrapFSyncDir :: CFSyncDir
wrapFSyncDir pFilePath isFullSync pFuseFileInfo = handle fuseHandler $
do filePath <- peekCString pFilePath
(Errno errno) <- (fuseSynchronizeDirectory ops)
filePath (toEnum isFullSync)
return (- errno)
wrapInit :: CInit
wrapInit = handle (\e -> hPutStrLn stderr (show e) >> return nullPtr) $
do fuseInit ops
return nullPtr
wrapDestroy :: CDestroy
wrapDestroy _ = handle (\e -> hPutStrLn stderr (show e)) $
do fuseDestroy ops
-- | Default exception handler.
-- Print the exception on error output and returns 'eFAULT'.
defaultExceptionHandler :: (Exception -> IO Errno)
defaultExceptionHandler e = hPutStrLn stderr (show e) >> return eFAULT
-----------------------------------------------------------------------------
-- Miscelaneous utilities
unErrno :: Errno -> CInt
unErrno (Errno errno) = errno
okErrno :: CInt
okErrno = 0
pokeCStringLen :: CStringLen -> String -> IO ()
pokeCStringLen (pBuf, bufSize) src =
pokeArray pBuf $ take bufSize $ map castCharToCChar src
pokeCStringLen0 :: CStringLen -> String -> IO ()
pokeCStringLen0 (pBuf, bufSize) src =
pokeArray0 0 pBuf $ take (bufSize - 1) $ map castCharToCChar src
-----------------------------------------------------------------------------
-- C land
---
-- exported C called from Haskell
---
data CFuseOperations
foreign import ccall threadsafe "fuse.h fuse_main_real"
fuse_main_real :: Int -> Ptr CString -> Ptr CFuseOperations -> CSize -> IO ()
data StructFuse
foreign import ccall threadsafe "fuse.h fuse_get_context"
fuse_get_context :: IO (Ptr StructFuse)
---
-- dynamic Haskell called from C
---
data CFuseFileInfo -- struct fuse_file_info
data CStat -- struct stat
type CGetAttr = CString -> Ptr CStat -> IO CInt
foreign import ccall threadsafe "wrapper"
mkGetAttr :: CGetAttr -> IO (FunPtr CGetAttr)
type CReadLink = CString -> CString -> CSize -> IO CInt
foreign import ccall threadsafe "wrapper"
mkReadLink :: CReadLink -> IO (FunPtr CReadLink)
type CGetDir = CString -> Ptr CDirHandle -> FunPtr CDirFil -> IO CInt
foreign import ccall threadsafe "wrapper"
mkGetDir :: CGetDir -> IO (FunPtr CGetDir)
type CMkNod = CString -> CMode -> CDev -> IO CInt
foreign import ccall threadsafe "wrapper"
mkMkNod :: CMkNod -> IO (FunPtr CMkNod)
type CMkDir = CString -> CMode -> IO CInt
foreign import ccall threadsafe "wrapper"
mkMkDir :: CMkDir -> IO (FunPtr CMkDir)
type CUnlink = CString -> IO CInt
foreign import ccall threadsafe "wrapper"
mkUnlink :: CUnlink -> IO (FunPtr CUnlink)
type CRmDir = CString -> IO CInt
foreign import ccall threadsafe "wrapper"
mkRmDir :: CRmDir -> IO (FunPtr CRmDir)
type CSymLink = CString -> CString -> IO CInt
foreign import ccall threadsafe "wrapper"
mkSymLink :: CSymLink -> IO (FunPtr CSymLink)
type CRename = CString -> CString -> IO CInt
foreign import ccall threadsafe "wrapper"
mkRename :: CRename -> IO (FunPtr CRename)
type CLink = CString -> CString -> IO CInt
foreign import ccall threadsafe "wrapper"
mkLink :: CLink -> IO (FunPtr CLink)
type CChMod = CString -> CMode -> IO CInt
foreign import ccall threadsafe "wrapper"
mkChMod :: CChMod -> IO (FunPtr CChMod)
type CChOwn = CString -> CUid -> CGid -> IO CInt
foreign import ccall threadsafe "wrapper"
mkChOwn :: CChOwn -> IO (FunPtr CChOwn)
type CTruncate = CString -> COff -> IO CInt
foreign import ccall threadsafe "wrapper"
mkTruncate :: CTruncate -> IO (FunPtr CTruncate)
data CUTimBuf -- struct utimbuf
type CUTime = CString -> Ptr CUTimBuf -> IO CInt
foreign import ccall threadsafe "wrapper"
mkUTime :: CUTime -> IO (FunPtr CUTime)
type COpen = CString -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkOpen :: COpen -> IO (FunPtr COpen)
type CRead = CString -> CString -> CSize -> COff -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkRead :: CRead -> IO (FunPtr CRead)
type CWrite = CString -> CString -> CSize -> COff -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkWrite :: CWrite -> IO (FunPtr CWrite)
data CStructStatFS -- struct fuse_stat_fs
type CStatFS = CString -> Ptr CStructStatFS -> IO CInt
foreign import ccall threadsafe "wrapper"
mkStatFS :: CStatFS -> IO (FunPtr CStatFS)
type CFlush = CString -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkFlush :: CFlush -> IO (FunPtr CFlush)
type CRelease = CString -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkRelease :: CRelease -> IO (FunPtr CRelease)
type CFSync = CString -> Int -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkFSync :: CFSync -> IO (FunPtr CFSync)
-- XXX add *xattr bindings
type COpenDir = CString -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkOpenDir :: COpenDir -> IO (FunPtr COpenDir)
type CReadDir = CString -> Ptr CFillDirBuf -> Ptr CFillDir -> COff -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkReadDir :: CReadDir -> IO (FunPtr CReadDir)
type CReleaseDir = CString -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkReleaseDir :: CReleaseDir -> IO (FunPtr CReleaseDir)
type CFSyncDir = CString -> Int -> Ptr CFuseFileInfo -> IO CInt
foreign import ccall threadsafe "wrapper"
mkFSyncDir :: CFSyncDir -> IO (FunPtr CFSyncDir)
-- CInt because anything would be fine as we don't use them
type CInit = IO (Ptr CInt)
foreign import ccall threadsafe "wrapper"
mkInit :: CInit -> IO (FunPtr CInit)
type CDestroy = Ptr CInt -> IO ()
foreign import ccall threadsafe "wrapper"
mkDestroy :: CDestroy -> IO (FunPtr CDestroy)
---
-- dynamic C called from Haskell
---
data CDirHandle -- fuse_dirh_t
type CDirFil = Ptr CDirHandle -> CString -> Int -> IO CInt -- fuse_dirfil_t
foreign import ccall threadsafe "dynamic"
mkDirFil :: FunPtr CDirFil -> CDirFil
data CFillDirBuf -- void
type CFillDir = Ptr CFillDirBuf -> CString -> Ptr CStat -> COff -> IO CInt
foreign import ccall threadsafe "dynamic"
mkFillDir :: FunPtr CFillDir -> CFillDir