{-# LANGUAGE CPP #-}
{-# LANGUAGE LambdaCase #-}
{-# OPTIONS_GHC -fno-warn-tabs #-}
module Utility.Directory.Stream where
import Control.Monad
import System.FilePath
import System.IO.Unsafe (unsafeInterleaveIO)
import Control.Concurrent
import Data.Maybe
import Prelude
#ifdef mingw32_HOST_OS
import qualified System.Win32 as Win32
#else
import qualified System.Posix as Posix
#endif
import Utility.Directory
import Utility.Exception
#ifndef mingw32_HOST_OS
data DirectoryHandle = DirectoryHandle IsOpen Posix.DirStream
#else
data DirectoryHandle = DirectoryHandle IsOpen Win32.HANDLE Win32.FindData (MVar ())
#endif
type IsOpen = MVar ()
openDirectory :: FilePath -> IO DirectoryHandle
openDirectory :: FilePath -> IO DirectoryHandle
openDirectory FilePath
path = do
#ifndef mingw32_HOST_OS
DirStream
dirp <- FilePath -> IO DirStream
Posix.openDirStream FilePath
path
MVar ()
isopen <- forall a. a -> IO (MVar a)
newMVar ()
forall (m :: * -> *) a. Monad m => a -> m a
return (MVar () -> DirStream -> DirectoryHandle
DirectoryHandle MVar ()
isopen DirStream
dirp)
#else
(h, fdat) <- Win32.findFirstFile (path </> "*")
alreadyhave <- newMVar ()
isopen <- newMVar ()
return (DirectoryHandle isopen h fdat alreadyhave)
#endif
closeDirectory :: DirectoryHandle -> IO ()
#ifndef mingw32_HOST_OS
closeDirectory :: DirectoryHandle -> IO ()
closeDirectory (DirectoryHandle MVar ()
isopen DirStream
dirp) =
MVar () -> IO () -> IO ()
whenOpen MVar ()
isopen forall a b. (a -> b) -> a -> b
$
DirStream -> IO ()
Posix.closeDirStream DirStream
dirp
#else
closeDirectory (DirectoryHandle isopen h _ alreadyhave) =
whenOpen isopen $ do
_ <- tryTakeMVar alreadyhave
Win32.findClose h
#endif
where
whenOpen :: IsOpen -> IO () -> IO ()
whenOpen :: MVar () -> IO () -> IO ()
whenOpen MVar ()
mv IO ()
f = do
Maybe ()
v <- forall a. MVar a -> IO (Maybe a)
tryTakeMVar MVar ()
mv
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when (forall a. Maybe a -> Bool
isJust Maybe ()
v) IO ()
f
readDirectory :: DirectoryHandle -> IO (Maybe FilePath)
#ifndef mingw32_HOST_OS
readDirectory :: DirectoryHandle -> IO (Maybe FilePath)
readDirectory hdl :: DirectoryHandle
hdl@(DirectoryHandle MVar ()
_ DirStream
dirp) = do
FilePath
e <- DirStream -> IO FilePath
Posix.readDirStream DirStream
dirp
if forall (t :: * -> *) a. Foldable t => t a -> Bool
null FilePath
e
then do
DirectoryHandle -> IO ()
closeDirectory DirectoryHandle
hdl
forall (m :: * -> *) a. Monad m => a -> m a
return forall a. Maybe a
Nothing
else forall (m :: * -> *) a. Monad m => a -> m a
return (forall a. a -> Maybe a
Just FilePath
e)
#else
readDirectory hdl@(DirectoryHandle _ h fdat mv) = do
r <- tryTakeMVar mv
case r of
Just () -> getfn
Nothing -> do
more <- Win32.findNextFile h fdat
if more
then getfn
else do
closeDirectory hdl
return Nothing
where
getfn = do
filename <- Win32.getFindDataFileName fdat
return (Just filename)
#endif
streamDirectoryContents :: FilePath -> IO [FilePath]
streamDirectoryContents :: FilePath -> IO [FilePath]
streamDirectoryContents FilePath
d = FilePath -> IO DirectoryHandle
openDirectory FilePath
d forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= DirectoryHandle -> IO [FilePath]
collect
where
collect :: DirectoryHandle -> IO [FilePath]
collect DirectoryHandle
hdl = DirectoryHandle -> IO (Maybe FilePath)
readDirectory DirectoryHandle
hdl forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= \case
Maybe FilePath
Nothing -> forall (m :: * -> *) a. Monad m => a -> m a
return []
Just FilePath
f -> do
[FilePath]
rest <- forall a. IO a -> IO a
unsafeInterleaveIO (DirectoryHandle -> IO [FilePath]
collect DirectoryHandle
hdl)
forall (m :: * -> *) a. Monad m => a -> m a
return (FilePath
fforall a. a -> [a] -> [a]
:[FilePath]
rest)
isDirectoryEmpty :: FilePath -> IO Bool
isDirectoryEmpty :: FilePath -> IO Bool
isDirectoryEmpty FilePath
d = forall (m :: * -> *) a c b.
MonadMask m =>
m a -> (a -> m c) -> (a -> m b) -> m b
bracket (FilePath -> IO DirectoryHandle
openDirectory FilePath
d) DirectoryHandle -> IO ()
closeDirectory DirectoryHandle -> IO Bool
check
where
check :: DirectoryHandle -> IO Bool
check DirectoryHandle
h = do
Maybe FilePath
v <- DirectoryHandle -> IO (Maybe FilePath)
readDirectory DirectoryHandle
h
case Maybe FilePath
v of
Maybe FilePath
Nothing -> forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
Just FilePath
f
| Bool -> Bool
not (FilePath -> Bool
dirCruft FilePath
f) -> forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
| Bool
otherwise -> DirectoryHandle -> IO Bool
check DirectoryHandle
h