From f1a4c2b98f1707c09e17ddd07cb25d6e1cfe4022 Mon Sep 17 00:00:00 2001 From: Egor Tensin Date: Mon, 12 Dec 2016 20:43:42 +0300 Subject: use monad transformers --- src/Windows/Registry.hs | 40 +++++++++++++++++++--------------------- 1 file changed, 19 insertions(+), 21 deletions(-) (limited to 'src/Windows/Registry.hs') diff --git a/src/Windows/Registry.hs b/src/Windows/Registry.hs index c0ead17..5203fb8 100644 --- a/src/Windows/Registry.hs +++ b/src/Windows/Registry.hs @@ -6,8 +6,6 @@ -- -- Low-level utility functions for reading and writing registry values. -{-# OPTIONS_GHC -XTupleSections #-} - module Windows.Registry ( IsKeyPath(..) , RootKey(..) @@ -45,6 +43,7 @@ import Data.Tuple (swap) import qualified Data.Text as T import Data.Text.Encoding (decodeUtf16LE, encodeUtf16LE) import Control.Exception (bracket) +import Control.Monad.Trans.Except (ExceptT(..), catchE, throwE) import Foreign.ForeignPtr (withForeignPtr) import Foreign.Marshal.Alloc (alloca, allocaBytes) import Foreign.Marshal.Array (peekArray, pokeArray) @@ -138,10 +137,10 @@ decodeString (_, bytes) = T.unpack dropLastZero | T.last text == '\0' = T.init text | otherwise = text -openCloseCatch :: IsKeyPath a => a -> (Handle -> IO b) -> IO (Either IOError b) -openCloseCatch keyPath f = catchIOError (fmap Right openClose) $ return . Left +openCloseCatch :: IsKeyPath a => a -> (Handle -> IO b) -> ExceptT IOError IO b +openCloseCatch keyPath f = ExceptT $ catchIOError (openApplyClose >>= return . Right) $ return . Left where - openClose = bracket (openUnsafe keyPath) close f + openApplyClose = bracket (openUnsafe keyPath) close f foreign import ccall unsafe "Windows.h RegQueryValueExW" c_RegQueryValueEx :: WinAPI.PKEY -> WinAPI.LPCTSTR -> WinAPI.LPDWORD -> WinAPI.LPDWORD -> WinAPI.LPBYTE -> WinAPI.LPDWORD -> IO WinAPI.ErrCode @@ -152,7 +151,7 @@ foreign import ccall unsafe "Windows.h RegSetValueExW" foreign import ccall unsafe "Windows.h RegGetValueW" c_RegGetValue :: WinAPI.PKEY -> WinAPI.LPCTSTR -> WinAPI.LPCTSTR -> WinAPI.DWORD -> WinAPI.LPDWORD -> WinAPI.LPBYTE -> WinAPI.LPDWORD -> IO WinAPI.ErrCode -queryValue :: IsKeyPath a => a -> ValueName -> IO (Either IOError ValueData) +queryValue :: IsKeyPath a => a -> ValueName -> ExceptT IOError IO ValueData queryValue keyPath valueName = openCloseCatch keyPath $ \keyHandle -> withForeignPtr keyHandle $ \keyHandlePtr -> @@ -170,7 +169,7 @@ queryValue keyPath valueName = valueType <- toEnum . fromIntegral <$> peek valueTypePtr return (valueType, buffer) -queryType :: IsKeyPath a => a -> ValueName -> IO (Either IOError ValueType) +queryType :: IsKeyPath a => a -> ValueName -> ExceptT IOError IO ValueType queryType keyPath valueName = openCloseCatch keyPath $ \keyHandle -> withForeignPtr keyHandle $ \keyHandlePtr -> @@ -209,7 +208,7 @@ getValueFlagsTable = , (DoNotExpand, 0x10000000) ] -getValue :: IsKeyPath a => a -> ValueName -> [GetValueFlag] -> IO (Either IOError ValueData) +getValue :: IsKeyPath a => a -> ValueName -> [GetValueFlag] -> ExceptT IOError IO ValueData getValue keyPath valueName flags = openCloseCatch keyPath $ \keyHandle -> withForeignPtr keyHandle $ \keyHandlePtr -> @@ -230,7 +229,7 @@ getValue keyPath valueName flags = where rawFlags = fromIntegral $ foldr (.|.) 0 $ map fromEnum flags -getType :: IsKeyPath a => a -> ValueName -> [GetValueFlag] -> IO (Either IOError ValueType) +getType :: IsKeyPath a => a -> ValueName -> [GetValueFlag] -> ExceptT IOError IO ValueType getType keyPath valueName flags = openCloseCatch keyPath $ \keyHandle -> withForeignPtr keyHandle $ \keyHandlePtr -> @@ -243,12 +242,12 @@ getType keyPath valueName flags = where rawFlags = fromIntegral $ foldr (.|.) 0 $ map fromEnum $ DoNotExpand : flags -getExpandedString :: IsKeyPath a => a -> ValueName -> IO (Either IOError String) +getExpandedString :: IsKeyPath a => a -> ValueName -> ExceptT IOError IO String getExpandedString keyPath valueName = do valueData <- getValue keyPath valueName [RestrictString, RestrictExpandableString] - return $ fmap decodeString valueData + return $ decodeString valueData -setValue :: IsKeyPath a => a -> ValueName -> ValueData -> IO (Either IOError ()) +setValue :: IsKeyPath a => a -> ValueName -> ValueData -> ExceptT IOError IO () setValue keyPath valueName (valueType, valueData) = openCloseCatch keyPath $ \keyHandle -> withForeignPtr keyHandle $ \keyHandlePtr -> @@ -262,24 +261,23 @@ setValue keyPath valueName (valueType, valueData) = buffer = B.unpack valueData bufferSize = B.length valueData -setString :: IsKeyPath a => a -> ValueName -> String -> IO (Either IOError ()) +setString :: IsKeyPath a => a -> ValueName -> String -> ExceptT IOError IO () setString keyPath valueName valueData = setValue keyPath valueName (TypeString, encodeString valueData) -setExpandableString :: IsKeyPath a => a -> ValueName -> String -> IO (Either IOError ()) +setExpandableString :: IsKeyPath a => a -> ValueName -> String -> ExceptT IOError IO () setExpandableString keyPath valueName valueData = setValue keyPath valueName (TypeExpandableString, encodeString valueData) -setStringPreserveType :: IsKeyPath a => a -> ValueName -> String -> IO (Either IOError ()) +setStringPreserveType :: IsKeyPath a => a -> ValueName -> String -> ExceptT IOError IO () setStringPreserveType keyPath valueName valueData = do - valueType <- stringIfMissing <$> getType keyPath valueName [RestrictString, RestrictExpandableString] - either (return . Left) (setValue keyPath valueName . (, encodeString valueData)) valueType + valueType <- getType keyPath valueName [RestrictString, RestrictExpandableString] `catchE` stringByDefault + setValue keyPath valueName (valueType, encodeString valueData) where - stringIfMissing (Left e) | isDoesNotExistError e = Right TypeString - | otherwise = Left e - stringIfMissing (Right x) = Right x + stringByDefault e | isDoesNotExistError e = return TypeString + | otherwise = throwE e -deleteValue :: IsKeyPath a => a -> ValueName -> IO (Either IOError ()) +deleteValue :: IsKeyPath a => a -> ValueName -> ExceptT IOError IO () deleteValue keyPath valueName = openCloseCatch keyPath $ \keyHandle -> withForeignPtr keyHandle $ \keyHandlePtr -> -- cgit v1.2.3