{-# LANGUAGE Trustworthy #-}
{-# LANGUAGE CPP
           , NoImplicitPrelude
           , RecordWildCards
           , NondecreasingIndentation
  #-}
{-# OPTIONS_GHC -Wno-unused-matches #-}

-----------------------------------------------------------------------------
-- |
-- Module      :  GHC.IO.Handle
-- Copyright   :  (c) The University of Glasgow, 1994-2009
-- License     :  see libraries/base/LICENSE
--
-- Maintainer  :  libraries@haskell.org
-- Stability   :  provisional
-- Portability :  non-portable
--
-- External API for GHC's Handle implementation
--
-----------------------------------------------------------------------------

module GHC.IO.Handle (
   Handle,
   BufferMode(..),

   mkFileHandle, mkDuplexHandle,

   hFileSize, hSetFileSize, hIsEOF, isEOF, hLookAhead,
   hSetBuffering, hSetBinaryMode, hSetEncoding, hGetEncoding,
   hFlush, hFlushAll, hDuplicate, hDuplicateTo,

   hClose, hClose_help,

   LockMode(..), hLock, hTryLock,

   HandlePosition, HandlePosn(..), hGetPosn, hSetPosn,
   SeekMode(..), hSeek, hTell,

   hIsOpen, hIsClosed, hIsReadable, hIsWritable, hGetBuffering, hIsSeekable,
   hSetEcho, hGetEcho, hIsTerminalDevice,

   hSetNewlineMode, Newline(..), NewlineMode(..), nativeNewline,
   noNewlineTranslation, universalNewlineMode, nativeNewlineMode,

   hShow,

   hWaitForInput, hGetChar, hGetLine, hGetContents, hPutChar, hPutStr,

   hGetBuf, hGetBufNonBlocking, hPutBuf, hPutBufNonBlocking
 ) where

import GHC.IO
import GHC.IO.Exception
import GHC.IO.Encoding
import GHC.IO.Buffer
import GHC.IO.BufferedIO ( BufferedIO )
import GHC.IO.Device as IODevice
import GHC.IO.Handle.FD
import GHC.IO.Handle.Lock
import GHC.IO.Handle.Types
import GHC.IO.Handle.Internals
import GHC.IO.Handle.Text
import qualified GHC.IO.BufferedIO as Buffered

import GHC.Base
import GHC.Exception
import GHC.MVar
import GHC.IORef
import GHC.Show
import GHC.Num
import GHC.Real
import Data.Maybe
import Data.Typeable

-- ---------------------------------------------------------------------------
-- Closing a handle

-- | Computation 'hClose' @hdl@ makes handle @hdl@ closed.  Before the
-- computation finishes, if @hdl@ is writable its buffer is flushed as
-- for 'hFlush'.
-- Performing 'hClose' on a handle that has already been closed has no effect;
-- doing so is not an error.  All other operations on a closed handle will fail.
-- If 'hClose' fails for any reason, any further operations (apart from
-- 'hClose') on the handle will still fail as if @hdl@ had been successfully
-- closed.

hClose :: Handle -> IO ()
hClose :: Handle -> IO ()
hClose h :: Handle
h@(FileHandle _ m :: MVar Handle__
m)     = do
  Maybe SomeException
mb_exc <- Handle -> MVar Handle__ -> IO (Maybe SomeException)
hClose' Handle
h MVar Handle__
m
  Maybe SomeException -> Handle -> IO ()
hClose_maybethrow Maybe SomeException
mb_exc Handle
h
hClose h :: Handle
h@(DuplexHandle _ r :: MVar Handle__
r w :: MVar Handle__
w) = do
  [Maybe SomeException]
excs <- (MVar Handle__ -> IO (Maybe SomeException))
-> [MVar Handle__] -> IO [Maybe SomeException]
forall (m :: * -> *) a b. Monad m => (a -> m b) -> [a] -> m [b]
mapM (Handle -> MVar Handle__ -> IO (Maybe SomeException)
hClose' Handle
h) [MVar Handle__
r,MVar Handle__
w]
  Maybe SomeException -> Handle -> IO ()
hClose_maybethrow ([SomeException] -> Maybe SomeException
forall a. [a] -> Maybe a
listToMaybe ([Maybe SomeException] -> [SomeException]
forall a. [Maybe a] -> [a]
catMaybes [Maybe SomeException]
excs)) Handle
h

hClose_maybethrow :: Maybe SomeException -> Handle -> IO ()
hClose_maybethrow :: Maybe SomeException -> Handle -> IO ()
hClose_maybethrow Nothing  h :: Handle
h = () -> IO ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
hClose_maybethrow (Just e :: SomeException
e) h :: Handle
h = SomeException -> Handle -> IO ()
hClose_rethrow SomeException
e Handle
h

hClose_rethrow :: SomeException -> Handle -> IO ()
hClose_rethrow :: SomeException -> Handle -> IO ()
hClose_rethrow e :: SomeException
e h :: Handle
h =
  case SomeException -> Maybe IOException
forall e. Exception e => SomeException -> Maybe e
fromException SomeException
e of
    Just ioe :: IOException
ioe -> IOException -> IO ()
forall a. IOException -> IO a
ioError (IOException -> String -> Handle -> IOException
augmentIOError IOException
ioe "hClose" Handle
h)
    Nothing  -> SomeException -> IO ()
forall e a. Exception e => e -> IO a
throwIO SomeException
e

hClose' :: Handle -> MVar Handle__ -> IO (Maybe SomeException)
hClose' :: Handle -> MVar Handle__ -> IO (Maybe SomeException)
hClose' h :: Handle
h m :: MVar Handle__
m = String
-> Handle
-> MVar Handle__
-> (Handle__ -> IO (Handle__, Maybe SomeException))
-> IO (Maybe SomeException)
forall a.
String
-> Handle
-> MVar Handle__
-> (Handle__ -> IO (Handle__, a))
-> IO a
withHandle' "hClose" Handle
h MVar Handle__
m ((Handle__ -> IO (Handle__, Maybe SomeException))
 -> IO (Maybe SomeException))
-> (Handle__ -> IO (Handle__, Maybe SomeException))
-> IO (Maybe SomeException)
forall a b. (a -> b) -> a -> b
$ Handle__ -> IO (Handle__, Maybe SomeException)
hClose_help

-----------------------------------------------------------------------------
-- Detecting and changing the size of a file

-- | For a handle @hdl@ which attached to a physical file,
-- 'hFileSize' @hdl@ returns the size of that file in 8-bit bytes.

hFileSize :: Handle -> IO Integer
hFileSize :: Handle -> IO Integer
hFileSize handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Integer) -> IO Integer
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hFileSize" Handle
handle ((Handle__ -> IO Integer) -> IO Integer)
-> (Handle__ -> IO Integer) -> IO Integer
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_@Handle__{haDevice :: ()
haDevice=dev
dev} -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle              -> IO Integer
forall a. IO a
ioe_closedHandle
      SemiClosedHandle          -> IO Integer
forall a. IO a
ioe_semiclosedHandle
      _ -> do Handle__ -> IO ()
flushWriteBuffer Handle__
handle_
              Integer
r <- dev -> IO Integer
forall a. IODevice a => a -> IO Integer
IODevice.getSize dev
dev
              if Integer
r Integer -> Integer -> Bool
forall a. Eq a => a -> a -> Bool
/= -1
                 then Integer -> IO Integer
forall (m :: * -> *) a. Monad m => a -> m a
return Integer
r
                 else IOException -> IO Integer
forall a. IOException -> IO a
ioException (Maybe Handle
-> IOErrorType
-> String
-> String
-> Maybe CInt
-> Maybe String
-> IOException
IOError Maybe Handle
forall a. Maybe a
Nothing IOErrorType
InappropriateType "hFileSize"
                                   "not a regular file" Maybe CInt
forall a. Maybe a
Nothing Maybe String
forall a. Maybe a
Nothing)


-- | 'hSetFileSize' @hdl@ @size@ truncates the physical file with handle @hdl@ to @size@ bytes.

hSetFileSize :: Handle -> Integer -> IO ()
hSetFileSize :: Handle -> Integer -> IO ()
hSetFileSize handle :: Handle
handle size :: Integer
size =
    String -> Handle -> (Handle__ -> IO ()) -> IO ()
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hSetFileSize" Handle
handle ((Handle__ -> IO ()) -> IO ()) -> (Handle__ -> IO ()) -> IO ()
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_@Handle__{haDevice :: ()
haDevice=dev
dev} -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle              -> IO ()
forall a. IO a
ioe_closedHandle
      SemiClosedHandle          -> IO ()
forall a. IO a
ioe_semiclosedHandle
      _ -> do Handle__ -> IO ()
flushWriteBuffer Handle__
handle_
              dev -> Integer -> IO ()
forall a. IODevice a => a -> Integer -> IO ()
IODevice.setSize dev
dev Integer
size
              () -> IO ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()

-- ---------------------------------------------------------------------------
-- Detecting the End of Input

-- | For a readable handle @hdl@, 'hIsEOF' @hdl@ returns
-- 'True' if no further input can be taken from @hdl@ or for a
-- physical file, if the current I\/O position is equal to the length of
-- the file.  Otherwise, it returns 'False'.
--
-- NOTE: 'hIsEOF' may block, because it has to attempt to read from
-- the stream to determine whether there is any more data to be read.

hIsEOF :: Handle -> IO Bool
hIsEOF :: Handle -> IO Bool
hIsEOF handle :: Handle
handle = String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
wantReadableHandle_ "hIsEOF" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \Handle__{..} -> do

  Buffer CharBufElem
cbuf <- IORef (Buffer CharBufElem) -> IO (Buffer CharBufElem)
forall a. IORef a -> IO a
readIORef IORef (Buffer CharBufElem)
haCharBuffer
  if Bool -> Bool
not (Buffer CharBufElem -> Bool
forall e. Buffer e -> Bool
isEmptyBuffer Buffer CharBufElem
cbuf) then Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False else do

  Buffer Word8
bbuf <- IORef (Buffer Word8) -> IO (Buffer Word8)
forall a. IORef a -> IO a
readIORef IORef (Buffer Word8)
haByteBuffer
  if Bool -> Bool
not (Buffer Word8 -> Bool
forall e. Buffer e -> Bool
isEmptyBuffer Buffer Word8
bbuf) then Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False else do

  -- NB. do no decoding, just fill the byte buffer; see #3808
  (r :: Int
r,bbuf' :: Buffer Word8
bbuf') <- dev -> Buffer Word8 -> IO (Int, Buffer Word8)
forall dev.
BufferedIO dev =>
dev -> Buffer Word8 -> IO (Int, Buffer Word8)
Buffered.fillReadBuffer dev
haDevice Buffer Word8
bbuf
  if Int
r Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
== 0
     then Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
     else do IORef (Buffer Word8) -> Buffer Word8 -> IO ()
forall a. IORef a -> a -> IO ()
writeIORef IORef (Buffer Word8)
haByteBuffer Buffer Word8
bbuf'
             Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False

-- ---------------------------------------------------------------------------
-- isEOF

-- | The computation 'isEOF' is identical to 'hIsEOF',
-- except that it works only on 'stdin'.

isEOF :: IO Bool
isEOF :: IO Bool
isEOF = Handle -> IO Bool
hIsEOF Handle
stdin

-- ---------------------------------------------------------------------------
-- Looking ahead

-- | Computation 'hLookAhead' returns the next character from the handle
-- without removing it from the input buffer, blocking until a character
-- is available.
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isEOFError' if the end of file has been reached.

hLookAhead :: Handle -> IO Char
hLookAhead :: Handle -> IO CharBufElem
hLookAhead handle :: Handle
handle =
  String -> Handle -> (Handle__ -> IO CharBufElem) -> IO CharBufElem
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
wantReadableHandle_ "hLookAhead"  Handle
handle Handle__ -> IO CharBufElem
hLookAhead_

-- ---------------------------------------------------------------------------
-- Buffering Operations

-- Three kinds of buffering are supported: line-buffering,
-- block-buffering or no-buffering.  See GHC.IO.Handle for definition and
-- further explanation of what the type represent.

-- | Computation 'hSetBuffering' @hdl mode@ sets the mode of buffering for
-- handle @hdl@ on subsequent reads and writes.
--
-- If the buffer mode is changed from 'BlockBuffering' or
-- 'LineBuffering' to 'NoBuffering', then
--
--  * if @hdl@ is writable, the buffer is flushed as for 'hFlush';
--
--  * if @hdl@ is not writable, the contents of the buffer is discarded.
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isPermissionError' if the handle has already been used
--    for reading or writing and the implementation does not allow the
--    buffering mode to be changed.

hSetBuffering :: Handle -> BufferMode -> IO ()
hSetBuffering :: Handle -> BufferMode -> IO ()
hSetBuffering handle :: Handle
handle mode :: BufferMode
mode =
  String -> Handle -> (Handle__ -> IO Handle__) -> IO ()
withAllHandles__ "hSetBuffering" Handle
handle ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_@Handle__{..} -> do
  case HandleType
haType of
    ClosedHandle -> IO Handle__
forall a. IO a
ioe_closedHandle
    _ -> do
         if BufferMode
mode BufferMode -> BufferMode -> Bool
forall a. Eq a => a -> a -> Bool
== BufferMode
haBufferMode then Handle__ -> IO Handle__
forall (m :: * -> *) a. Monad m => a -> m a
return Handle__
handle_ else do

         -- See [note Buffer Sizing] in GHC.IO.Handle.Types

          -- check for errors:
          case BufferMode
mode of
              BlockBuffering (Just n :: Int
n) | Int
n Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
<= 0    -> Int -> IO ()
forall a. Int -> IO a
ioe_bufsiz Int
n
              _ -> () -> IO ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()

          -- for input terminals we need to put the terminal into
          -- cooked or raw mode depending on the type of buffering.
          Bool
is_tty <- dev -> IO Bool
forall a. IODevice a => a -> IO Bool
IODevice.isTerminal dev
haDevice
          Bool -> IO () -> IO ()
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when (Bool
is_tty Bool -> Bool -> Bool
&& HandleType -> Bool
isReadableHandleType HandleType
haType) (IO () -> IO ()) -> IO () -> IO ()
forall a b. (a -> b) -> a -> b
$
                case BufferMode
mode of
#if !defined(mingw32_HOST_OS)
        -- 'raw' mode under win32 is a bit too specialised (and troublesome
        -- for most common uses), so simply disable its use here.
                  NoBuffering -> dev -> Bool -> IO ()
forall a. IODevice a => a -> Bool -> IO ()
IODevice.setRaw dev
haDevice Bool
True
#else
                  NoBuffering -> return ()
#endif
                  _           -> dev -> Bool -> IO ()
forall a. IODevice a => a -> Bool -> IO ()
IODevice.setRaw dev
haDevice Bool
False

          -- throw away spare buffers, they might be the wrong size
          IORef (BufferList CharBufElem) -> BufferList CharBufElem -> IO ()
forall a. IORef a -> a -> IO ()
writeIORef IORef (BufferList CharBufElem)
haBuffers BufferList CharBufElem
forall e. BufferList e
BufferListNil

          Handle__ -> IO Handle__
forall (m :: * -> *) a. Monad m => a -> m a
return $WHandle__ :: forall dev enc_state dec_state.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> HandleType
-> IORef (Buffer Word8)
-> BufferMode
-> IORef (dec_state, Buffer Word8)
-> IORef (Buffer CharBufElem)
-> IORef (BufferList CharBufElem)
-> Maybe (TextEncoder enc_state)
-> Maybe (TextDecoder dec_state)
-> Maybe TextEncoding
-> Newline
-> Newline
-> Maybe (MVar Handle__)
-> Handle__
Handle__{ haBufferMode :: BufferMode
haBufferMode = BufferMode
mode,.. }

-- -----------------------------------------------------------------------------
-- hSetEncoding

-- | The action 'hSetEncoding' @hdl@ @encoding@ changes the text encoding
-- for the handle @hdl@ to @encoding@.  The default encoding when a 'Handle' is
-- created is 'System.IO.localeEncoding', namely the default encoding for the
-- current locale.
--
-- To create a 'Handle' with no encoding at all, use 'openBinaryFile'.  To
-- stop further encoding or decoding on an existing 'Handle', use
-- 'hSetBinaryMode'.
--
-- 'hSetEncoding' may need to flush buffered data in order to change
-- the encoding.
--
hSetEncoding :: Handle -> TextEncoding -> IO ()
hSetEncoding :: Handle -> TextEncoding -> IO ()
hSetEncoding hdl :: Handle
hdl encoding :: TextEncoding
encoding = do
  String -> Handle -> (Handle__ -> IO Handle__) -> IO ()
withAllHandles__ "hSetEncoding" Handle
hdl ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \h_ :: Handle__
h_@Handle__{..} -> do
    Handle__ -> IO ()
flushCharBuffer Handle__
h_
    Handle__ -> IO ()
closeTextCodecs Handle__
h_
    Maybe TextEncoding
-> HandleType
-> (forall es ds.
    Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO Handle__)
-> IO Handle__
forall a.
Maybe TextEncoding
-> HandleType
-> (forall es ds.
    Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO a)
-> IO a
openTextEncoding (TextEncoding -> Maybe TextEncoding
forall a. a -> Maybe a
Just TextEncoding
encoding) HandleType
haType ((forall es ds.
  Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO Handle__)
 -> IO Handle__)
-> (forall es ds.
    Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO Handle__)
-> IO Handle__
forall a b. (a -> b) -> a -> b
$ \ mb_encoder :: Maybe (TextEncoder es)
mb_encoder mb_decoder :: Maybe (TextDecoder ds)
mb_decoder -> do
    Buffer Word8
bbuf <- IORef (Buffer Word8) -> IO (Buffer Word8)
forall a. IORef a -> IO a
readIORef IORef (Buffer Word8)
haByteBuffer
    IORef (ds, Buffer Word8)
ref <- (ds, Buffer Word8) -> IO (IORef (ds, Buffer Word8))
forall a. a -> IO (IORef a)
newIORef (String -> (ds, Buffer Word8)
forall a. String -> a
errorWithoutStackTrace "last_decode")
    Handle__ -> IO Handle__
forall (m :: * -> *) a. Monad m => a -> m a
return ($WHandle__ :: forall dev enc_state dec_state.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> HandleType
-> IORef (Buffer Word8)
-> BufferMode
-> IORef (dec_state, Buffer Word8)
-> IORef (Buffer CharBufElem)
-> IORef (BufferList CharBufElem)
-> Maybe (TextEncoder enc_state)
-> Maybe (TextDecoder dec_state)
-> Maybe TextEncoding
-> Newline
-> Newline
-> Maybe (MVar Handle__)
-> Handle__
Handle__{ haLastDecode :: IORef (ds, Buffer Word8)
haLastDecode = IORef (ds, Buffer Word8)
ref,
                      haDecoder :: Maybe (TextDecoder ds)
haDecoder = Maybe (TextDecoder ds)
mb_decoder,
                      haEncoder :: Maybe (TextEncoder es)
haEncoder = Maybe (TextEncoder es)
mb_encoder,
                      haCodec :: Maybe TextEncoding
haCodec   = TextEncoding -> Maybe TextEncoding
forall a. a -> Maybe a
Just TextEncoding
encoding, .. })

-- | Return the current 'TextEncoding' for the specified 'Handle', or
-- 'Nothing' if the 'Handle' is in binary mode.
--
-- Note that the 'TextEncoding' remembers nothing about the state of
-- the encoder/decoder in use on this 'Handle'.  For example, if the
-- encoding in use is UTF-16, then using 'hGetEncoding' and
-- 'hSetEncoding' to save and restore the encoding may result in an
-- extra byte-order-mark being written to the file.
--
hGetEncoding :: Handle -> IO (Maybe TextEncoding)
hGetEncoding :: Handle -> IO (Maybe TextEncoding)
hGetEncoding hdl :: Handle
hdl =
  String
-> Handle
-> (Handle__ -> IO (Maybe TextEncoding))
-> IO (Maybe TextEncoding)
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hGetEncoding" Handle
hdl ((Handle__ -> IO (Maybe TextEncoding)) -> IO (Maybe TextEncoding))
-> (Handle__ -> IO (Maybe TextEncoding)) -> IO (Maybe TextEncoding)
forall a b. (a -> b) -> a -> b
$ \h_ :: Handle__
h_@Handle__{..} -> Maybe TextEncoding -> IO (Maybe TextEncoding)
forall (m :: * -> *) a. Monad m => a -> m a
return Maybe TextEncoding
haCodec

-- -----------------------------------------------------------------------------
-- hFlush

-- | The action 'hFlush' @hdl@ causes any items buffered for output
-- in handle @hdl@ to be sent immediately to the operating system.
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isFullError' if the device is full;
--
--  * 'System.IO.Error.isPermissionError' if a system resource limit would be
--    exceeded. It is unspecified whether the characters in the buffer are
--    discarded or retained under these circumstances.

hFlush :: Handle -> IO ()
hFlush :: Handle -> IO ()
hFlush handle :: Handle
handle = String -> Handle -> (Handle__ -> IO ()) -> IO ()
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
wantWritableHandle "hFlush" Handle
handle Handle__ -> IO ()
flushWriteBuffer

-- | The action 'hFlushAll' @hdl@ flushes all buffered data in @hdl@,
-- including any buffered read data.  Buffered read data is flushed
-- by seeking the file position back to the point before the bufferred
-- data was read, and hence only works if @hdl@ is seekable (see
-- 'hIsSeekable').
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isFullError' if the device is full;
--
--  * 'System.IO.Error.isPermissionError' if a system resource limit would be
--    exceeded. It is unspecified whether the characters in the buffer are
--    discarded or retained under these circumstances;
--
--  * 'System.IO.Error.isIllegalOperation' if @hdl@ has buffered read data, and
--    is not seekable.

hFlushAll :: Handle -> IO ()
hFlushAll :: Handle -> IO ()
hFlushAll handle :: Handle
handle = String -> Handle -> (Handle__ -> IO ()) -> IO ()
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hFlushAll" Handle
handle Handle__ -> IO ()
flushBuffer

-- -----------------------------------------------------------------------------
-- Repositioning Handles

data HandlePosn = HandlePosn Handle HandlePosition

-- | @since 4.1.0.0
instance Eq HandlePosn where
    (HandlePosn h1 :: Handle
h1 p1 :: Integer
p1) == :: HandlePosn -> HandlePosn -> Bool
== (HandlePosn h2 :: Handle
h2 p2 :: Integer
p2) = Integer
p1Integer -> Integer -> Bool
forall a. Eq a => a -> a -> Bool
==Integer
p2 Bool -> Bool -> Bool
&& Handle
h1Handle -> Handle -> Bool
forall a. Eq a => a -> a -> Bool
==Handle
h2

-- | @since 4.1.0.0
instance Show HandlePosn where
   showsPrec :: Int -> HandlePosn -> ShowS
showsPrec p :: Int
p (HandlePosn h :: Handle
h pos :: Integer
pos) =
        Int -> Handle -> ShowS
forall a. Show a => Int -> a -> ShowS
showsPrec Int
p Handle
h ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. String -> ShowS
showString " at position " ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Integer -> ShowS
forall a. Show a => a -> ShowS
shows Integer
pos

  -- HandlePosition is the Haskell equivalent of POSIX' off_t.
  -- We represent it as an Integer on the Haskell side, but
  -- cheat slightly in that hGetPosn calls upon a C helper
  -- that reports the position back via (merely) an Int.
type HandlePosition = Integer

-- | Computation 'hGetPosn' @hdl@ returns the current I\/O position of
-- @hdl@ as a value of the abstract type 'HandlePosn'.

hGetPosn :: Handle -> IO HandlePosn
hGetPosn :: Handle -> IO HandlePosn
hGetPosn handle :: Handle
handle = do
    Integer
posn <- Handle -> IO Integer
hTell Handle
handle
    HandlePosn -> IO HandlePosn
forall (m :: * -> *) a. Monad m => a -> m a
return (Handle -> Integer -> HandlePosn
HandlePosn Handle
handle Integer
posn)

-- | If a call to 'hGetPosn' @hdl@ returns a position @p@,
-- then computation 'hSetPosn' @p@ sets the position of @hdl@
-- to the position it held at the time of the call to 'hGetPosn'.
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isPermissionError' if a system resource limit would be
--    exceeded.

hSetPosn :: HandlePosn -> IO ()
hSetPosn :: HandlePosn -> IO ()
hSetPosn (HandlePosn h :: Handle
h i :: Integer
i) = Handle -> SeekMode -> Integer -> IO ()
hSeek Handle
h SeekMode
AbsoluteSeek Integer
i

-- ---------------------------------------------------------------------------
-- hSeek

{- Note:
 - when seeking using `SeekFromEnd', positive offsets (>=0) means
   seeking at or past EOF.

 - we possibly deviate from the report on the issue of seeking within
   the buffer and whether to flush it or not.  The report isn't exactly
   clear here.
-}

-- | Computation 'hSeek' @hdl mode i@ sets the position of handle
-- @hdl@ depending on @mode@.
-- The offset @i@ is given in terms of 8-bit bytes.
--
-- If @hdl@ is block- or line-buffered, then seeking to a position which is not
-- in the current buffer will first cause any items in the output buffer to be
-- written to the device, and then cause the input buffer to be discarded.
-- Some handles may not be seekable (see 'hIsSeekable'), or only support a
-- subset of the possible positioning operations (for instance, it may only
-- be possible to seek to the end of a tape, or to a positive offset from
-- the beginning or current position).
-- It is not possible to set a negative I\/O position, or for
-- a physical file, an I\/O position beyond the current end-of-file.
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isIllegalOperationError' if the Handle is not seekable,
--    or does not support the requested seek mode.
--
--  * 'System.IO.Error.isPermissionError' if a system resource limit would be
--    exceeded.

hSeek :: Handle -> SeekMode -> Integer -> IO ()
hSeek :: Handle -> SeekMode -> Integer -> IO ()
hSeek handle :: Handle
handle mode :: SeekMode
mode offset :: Integer
offset =
    String -> Handle -> (Handle__ -> IO ()) -> IO ()
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
wantSeekableHandle "hSeek" Handle
handle ((Handle__ -> IO ()) -> IO ()) -> (Handle__ -> IO ()) -> IO ()
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_@Handle__{..} -> do
    String -> IO ()
debugIO ("hSeek " String -> ShowS
forall a. [a] -> [a] -> [a]
++ (SeekMode, Integer) -> String
forall a. Show a => a -> String
show (SeekMode
mode,Integer
offset))
    Buffer CharBufElem
buf <- IORef (Buffer CharBufElem) -> IO (Buffer CharBufElem)
forall a. IORef a -> IO a
readIORef IORef (Buffer CharBufElem)
haCharBuffer

    if Buffer CharBufElem -> Bool
forall e. Buffer e -> Bool
isWriteBuffer Buffer CharBufElem
buf
        then do Handle__ -> IO ()
flushWriteBuffer Handle__
handle_
                dev -> SeekMode -> Integer -> IO ()
forall a. IODevice a => a -> SeekMode -> Integer -> IO ()
IODevice.seek dev
haDevice SeekMode
mode Integer
offset
        else do

    let r :: Int
r = Buffer CharBufElem -> Int
forall e. Buffer e -> Int
bufL Buffer CharBufElem
buf; w :: Int
w = Buffer CharBufElem -> Int
forall e. Buffer e -> Int
bufR Buffer CharBufElem
buf
    if SeekMode
mode SeekMode -> SeekMode -> Bool
forall a. Eq a => a -> a -> Bool
== SeekMode
RelativeSeek Bool -> Bool -> Bool
&& Maybe (TextDecoder dec_state) -> Bool
forall a. Maybe a -> Bool
isNothing Maybe (TextDecoder dec_state)
haDecoder Bool -> Bool -> Bool
&&
       Integer
offset Integer -> Integer -> Bool
forall a. Ord a => a -> a -> Bool
>= 0 Bool -> Bool -> Bool
&& Integer
offset Integer -> Integer -> Bool
forall a. Ord a => a -> a -> Bool
< Int -> Integer
forall a b. (Integral a, Num b) => a -> b
fromIntegral (Int
w Int -> Int -> Int
forall a. Num a => a -> a -> a
- Int
r)
        then IORef (Buffer CharBufElem) -> Buffer CharBufElem -> IO ()
forall a. IORef a -> a -> IO ()
writeIORef IORef (Buffer CharBufElem)
haCharBuffer Buffer CharBufElem
buf{ bufL :: Int
bufL = Int
r Int -> Int -> Int
forall a. Num a => a -> a -> a
+ Integer -> Int
forall a b. (Integral a, Num b) => a -> b
fromIntegral Integer
offset }
        else do

    Handle__ -> IO ()
flushCharReadBuffer Handle__
handle_
    Handle__ -> IO ()
flushByteReadBuffer Handle__
handle_
    dev -> SeekMode -> Integer -> IO ()
forall a. IODevice a => a -> SeekMode -> Integer -> IO ()
IODevice.seek dev
haDevice SeekMode
mode Integer
offset


-- | Computation 'hTell' @hdl@ returns the current position of the
-- handle @hdl@, as the number of bytes from the beginning of
-- the file.  The value returned may be subsequently passed to
-- 'hSeek' to reposition the handle to the current position.
--
-- This operation may fail with:
--
--  * 'System.IO.Error.isIllegalOperationError' if the Handle is not seekable.
--
hTell :: Handle -> IO Integer
hTell :: Handle -> IO Integer
hTell handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Integer) -> IO Integer
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
wantSeekableHandle "hGetPosn" Handle
handle ((Handle__ -> IO Integer) -> IO Integer)
-> (Handle__ -> IO Integer) -> IO Integer
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_@Handle__{..} -> do

      Integer
posn <- dev -> IO Integer
forall a. IODevice a => a -> IO Integer
IODevice.tell dev
haDevice

      -- we can't tell the real byte offset if there are buffered
      -- Chars, so must flush first:
      Handle__ -> IO ()
flushCharBuffer Handle__
handle_

      Buffer Word8
bbuf <- IORef (Buffer Word8) -> IO (Buffer Word8)
forall a. IORef a -> IO a
readIORef IORef (Buffer Word8)
haByteBuffer

      let real_posn :: Integer
real_posn
           | Buffer Word8 -> Bool
forall e. Buffer e -> Bool
isWriteBuffer Buffer Word8
bbuf = Integer
posn Integer -> Integer -> Integer
forall a. Num a => a -> a -> a
+ Int -> Integer
forall a b. (Integral a, Num b) => a -> b
fromIntegral (Buffer Word8 -> Int
forall e. Buffer e -> Int
bufferElems Buffer Word8
bbuf)
           | Bool
otherwise          = Integer
posn Integer -> Integer -> Integer
forall a. Num a => a -> a -> a
- Int -> Integer
forall a b. (Integral a, Num b) => a -> b
fromIntegral (Buffer Word8 -> Int
forall e. Buffer e -> Int
bufferElems Buffer Word8
bbuf)

      Buffer CharBufElem
cbuf <- IORef (Buffer CharBufElem) -> IO (Buffer CharBufElem)
forall a. IORef a -> IO a
readIORef IORef (Buffer CharBufElem)
haCharBuffer
      String -> IO ()
debugIO ("\nhGetPosn: (posn, real_posn) = " String -> ShowS
forall a. [a] -> [a] -> [a]
++ (Integer, Integer) -> String
forall a. Show a => a -> String
show (Integer
posn, Integer
real_posn))
      String -> IO ()
debugIO ("   cbuf: " String -> ShowS
forall a. [a] -> [a] -> [a]
++ Buffer CharBufElem -> String
forall a. Buffer a -> String
summaryBuffer Buffer CharBufElem
cbuf String -> ShowS
forall a. [a] -> [a] -> [a]
++
            "   bbuf: " String -> ShowS
forall a. [a] -> [a] -> [a]
++ Buffer Word8 -> String
forall a. Buffer a -> String
summaryBuffer Buffer Word8
bbuf)

      Integer -> IO Integer
forall (m :: * -> *) a. Monad m => a -> m a
return Integer
real_posn

-- -----------------------------------------------------------------------------
-- Handle Properties

-- A number of operations return information about the properties of a
-- handle.  Each of these operations returns `True' if the handle has
-- the specified property, and `False' otherwise.

hIsOpen :: Handle -> IO Bool
hIsOpen :: Handle -> IO Bool
hIsOpen handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hIsOpen" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_ -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle         -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
      SemiClosedHandle     -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
      _                    -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True

hIsClosed :: Handle -> IO Bool
hIsClosed :: Handle -> IO Bool
hIsClosed handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hIsClosed" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_ -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle         -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
      _                    -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False

{- not defined, nor exported, but mentioned
   here for documentation purposes:

    hSemiClosed :: Handle -> IO Bool
    hSemiClosed h = do
       ho <- hIsOpen h
       hc <- hIsClosed h
       return (not (ho || hc))
-}

hIsReadable :: Handle -> IO Bool
hIsReadable :: Handle -> IO Bool
hIsReadable (DuplexHandle _ _ _) = Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
hIsReadable handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hIsReadable" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_ -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle         -> IO Bool
forall a. IO a
ioe_closedHandle
      SemiClosedHandle     -> IO Bool
forall a. IO a
ioe_semiclosedHandle
      htype :: HandleType
htype                -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return (HandleType -> Bool
isReadableHandleType HandleType
htype)

hIsWritable :: Handle -> IO Bool
hIsWritable :: Handle -> IO Bool
hIsWritable (DuplexHandle _ _ _) = Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
True
hIsWritable handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hIsWritable" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_ -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle         -> IO Bool
forall a. IO a
ioe_closedHandle
      SemiClosedHandle     -> IO Bool
forall a. IO a
ioe_semiclosedHandle
      htype :: HandleType
htype                -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return (HandleType -> Bool
isWritableHandleType HandleType
htype)

-- | Computation 'hGetBuffering' @hdl@ returns the current buffering mode
-- for @hdl@.

hGetBuffering :: Handle -> IO BufferMode
hGetBuffering :: Handle -> IO BufferMode
hGetBuffering handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO BufferMode) -> IO BufferMode
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hGetBuffering" Handle
handle ((Handle__ -> IO BufferMode) -> IO BufferMode)
-> (Handle__ -> IO BufferMode) -> IO BufferMode
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_ -> do
    case Handle__ -> HandleType
haType Handle__
handle_ of
      ClosedHandle         -> IO BufferMode
forall a. IO a
ioe_closedHandle
      _ ->
           -- We're being non-standard here, and allow the buffering
           -- of a semi-closed handle to be queried.   -- sof 6/98
          BufferMode -> IO BufferMode
forall (m :: * -> *) a. Monad m => a -> m a
return (Handle__ -> BufferMode
haBufferMode Handle__
handle_)  -- could be stricter..

hIsSeekable :: Handle -> IO Bool
hIsSeekable :: Handle -> IO Bool
hIsSeekable handle :: Handle
handle =
    String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hIsSeekable" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ handle_ :: Handle__
handle_@Handle__{..} -> do
    case HandleType
haType of
      ClosedHandle         -> IO Bool
forall a. IO a
ioe_closedHandle
      SemiClosedHandle     -> IO Bool
forall a. IO a
ioe_semiclosedHandle
      AppendHandle         -> Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
      _                    -> dev -> IO Bool
forall a. IODevice a => a -> IO Bool
IODevice.isSeekable dev
haDevice

-- -----------------------------------------------------------------------------
-- Changing echo status

-- | Set the echoing status of a handle connected to a terminal.

hSetEcho :: Handle -> Bool -> IO ()
hSetEcho :: Handle -> Bool -> IO ()
hSetEcho handle :: Handle
handle on :: Bool
on = do
    Bool
isT   <- Handle -> IO Bool
hIsTerminalDevice Handle
handle
    if Bool -> Bool
not Bool
isT
     then () -> IO ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
     else
      String -> Handle -> (Handle__ -> IO ()) -> IO ()
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hSetEcho" Handle
handle ((Handle__ -> IO ()) -> IO ()) -> (Handle__ -> IO ()) -> IO ()
forall a b. (a -> b) -> a -> b
$ \ Handle__{..} -> do
      case HandleType
haType of
         ClosedHandle -> IO ()
forall a. IO a
ioe_closedHandle
         _            -> dev -> Bool -> IO ()
forall a. IODevice a => a -> Bool -> IO ()
IODevice.setEcho dev
haDevice Bool
on

-- | Get the echoing status of a handle connected to a terminal.

hGetEcho :: Handle -> IO Bool
hGetEcho :: Handle -> IO Bool
hGetEcho handle :: Handle
handle = do
    Bool
isT   <- Handle -> IO Bool
hIsTerminalDevice Handle
handle
    if Bool -> Bool
not Bool
isT
     then Bool -> IO Bool
forall (m :: * -> *) a. Monad m => a -> m a
return Bool
False
     else
       String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hGetEcho" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ Handle__{..} -> do
       case HandleType
haType of
         ClosedHandle -> IO Bool
forall a. IO a
ioe_closedHandle
         _            -> dev -> IO Bool
forall a. IODevice a => a -> IO Bool
IODevice.getEcho dev
haDevice

-- | Is the handle connected to a terminal?

hIsTerminalDevice :: Handle -> IO Bool
hIsTerminalDevice :: Handle -> IO Bool
hIsTerminalDevice handle :: Handle
handle = do
    String -> Handle -> (Handle__ -> IO Bool) -> IO Bool
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "hIsTerminalDevice" Handle
handle ((Handle__ -> IO Bool) -> IO Bool)
-> (Handle__ -> IO Bool) -> IO Bool
forall a b. (a -> b) -> a -> b
$ \ Handle__{..} -> do
     case HandleType
haType of
       ClosedHandle -> IO Bool
forall a. IO a
ioe_closedHandle
       _            -> dev -> IO Bool
forall a. IODevice a => a -> IO Bool
IODevice.isTerminal dev
haDevice

-- -----------------------------------------------------------------------------
-- hSetBinaryMode

-- | Select binary mode ('True') or text mode ('False') on a open handle.
-- (See also 'openBinaryFile'.)
--
-- This has the same effect as calling 'hSetEncoding' with 'char8', together
-- with 'hSetNewlineMode' with 'noNewlineTranslation'.
--
hSetBinaryMode :: Handle -> Bool -> IO ()
hSetBinaryMode :: Handle -> Bool -> IO ()
hSetBinaryMode handle :: Handle
handle bin :: Bool
bin =
  String -> Handle -> (Handle__ -> IO Handle__) -> IO ()
withAllHandles__ "hSetBinaryMode" Handle
handle ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \ h_ :: Handle__
h_@Handle__{..} ->
    do
         Handle__ -> IO ()
flushCharBuffer Handle__
h_
         Handle__ -> IO ()
closeTextCodecs Handle__
h_

         Maybe TextEncoding
mb_te <- if Bool
bin then Maybe TextEncoding -> IO (Maybe TextEncoding)
forall (m :: * -> *) a. Monad m => a -> m a
return Maybe TextEncoding
forall a. Maybe a
Nothing
                         else (TextEncoding -> Maybe TextEncoding)
-> IO TextEncoding -> IO (Maybe TextEncoding)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap TextEncoding -> Maybe TextEncoding
forall a. a -> Maybe a
Just IO TextEncoding
getLocaleEncoding

         Maybe TextEncoding
-> HandleType
-> (forall es ds.
    Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO Handle__)
-> IO Handle__
forall a.
Maybe TextEncoding
-> HandleType
-> (forall es ds.
    Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO a)
-> IO a
openTextEncoding Maybe TextEncoding
mb_te HandleType
haType ((forall es ds.
  Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO Handle__)
 -> IO Handle__)
-> (forall es ds.
    Maybe (TextEncoder es) -> Maybe (TextDecoder ds) -> IO Handle__)
-> IO Handle__
forall a b. (a -> b) -> a -> b
$ \ mb_encoder :: Maybe (TextEncoder es)
mb_encoder mb_decoder :: Maybe (TextDecoder ds)
mb_decoder -> do

         -- should match the default newline mode, whatever that is
         let nl :: NewlineMode
nl    | Bool
bin       = NewlineMode
noNewlineTranslation
                   | Bool
otherwise = NewlineMode
nativeNewlineMode

         Buffer Word8
bbuf <- IORef (Buffer Word8) -> IO (Buffer Word8)
forall a. IORef a -> IO a
readIORef IORef (Buffer Word8)
haByteBuffer
         IORef (ds, Buffer Word8)
ref <- (ds, Buffer Word8) -> IO (IORef (ds, Buffer Word8))
forall a. a -> IO (IORef a)
newIORef (String -> ds
forall a. String -> a
errorWithoutStackTrace "codec_state", Buffer Word8
bbuf)

         Handle__ -> IO Handle__
forall (m :: * -> *) a. Monad m => a -> m a
return $WHandle__ :: forall dev enc_state dec_state.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> HandleType
-> IORef (Buffer Word8)
-> BufferMode
-> IORef (dec_state, Buffer Word8)
-> IORef (Buffer CharBufElem)
-> IORef (BufferList CharBufElem)
-> Maybe (TextEncoder enc_state)
-> Maybe (TextDecoder dec_state)
-> Maybe TextEncoding
-> Newline
-> Newline
-> Maybe (MVar Handle__)
-> Handle__
Handle__{ haLastDecode :: IORef (ds, Buffer Word8)
haLastDecode = IORef (ds, Buffer Word8)
ref,
                          haEncoder :: Maybe (TextEncoder es)
haEncoder  = Maybe (TextEncoder es)
mb_encoder,
                          haDecoder :: Maybe (TextDecoder ds)
haDecoder  = Maybe (TextDecoder ds)
mb_decoder,
                          haCodec :: Maybe TextEncoding
haCodec    = Maybe TextEncoding
mb_te,
                          haInputNL :: Newline
haInputNL  = NewlineMode -> Newline
inputNL NewlineMode
nl,
                          haOutputNL :: Newline
haOutputNL = NewlineMode -> Newline
outputNL NewlineMode
nl, .. }

-- -----------------------------------------------------------------------------
-- hSetNewlineMode

-- | Set the 'NewlineMode' on the specified 'Handle'.  All buffered
-- data is flushed first.
hSetNewlineMode :: Handle -> NewlineMode -> IO ()
hSetNewlineMode :: Handle -> NewlineMode -> IO ()
hSetNewlineMode handle :: Handle
handle NewlineMode{ inputNL :: NewlineMode -> Newline
inputNL=Newline
i, outputNL :: NewlineMode -> Newline
outputNL=Newline
o } =
  String -> Handle -> (Handle__ -> IO Handle__) -> IO ()
withAllHandles__ "hSetNewlineMode" Handle
handle ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \h_ :: Handle__
h_@Handle__{..} ->
    do
         Handle__ -> IO ()
flushBuffer Handle__
h_
         Handle__ -> IO Handle__
forall (m :: * -> *) a. Monad m => a -> m a
return Handle__
h_{ haInputNL :: Newline
haInputNL=Newline
i, haOutputNL :: Newline
haOutputNL=Newline
o }

-- -----------------------------------------------------------------------------
-- Duplicating a Handle

-- | Returns a duplicate of the original handle, with its own buffer.
-- The two Handles will share a file pointer, however.  The original
-- handle's buffer is flushed, including discarding any input data,
-- before the handle is duplicated.

hDuplicate :: Handle -> IO Handle
hDuplicate :: Handle -> IO Handle
hDuplicate h :: Handle
h@(FileHandle path :: String
path m :: MVar Handle__
m) = do
  String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle) -> IO Handle
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "hDuplicate" Handle
h MVar Handle__
m ((Handle__ -> IO Handle) -> IO Handle)
-> (Handle__ -> IO Handle) -> IO Handle
forall a b. (a -> b) -> a -> b
$ \h_ :: Handle__
h_ ->
      String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle String
path Handle
h Maybe (MVar Handle__)
forall a. Maybe a
Nothing Handle__
h_ (HandleFinalizer -> Maybe HandleFinalizer
forall a. a -> Maybe a
Just HandleFinalizer
handleFinalizer)
hDuplicate h :: Handle
h@(DuplexHandle path :: String
path r :: MVar Handle__
r w :: MVar Handle__
w) = do
  write_side :: Handle
write_side@(FileHandle _ write_m :: MVar Handle__
write_m) <-
     String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle) -> IO Handle
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "hDuplicate" Handle
h MVar Handle__
w ((Handle__ -> IO Handle) -> IO Handle)
-> (Handle__ -> IO Handle) -> IO Handle
forall a b. (a -> b) -> a -> b
$ \h_ :: Handle__
h_ ->
        String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle String
path Handle
h Maybe (MVar Handle__)
forall a. Maybe a
Nothing Handle__
h_ (HandleFinalizer -> Maybe HandleFinalizer
forall a. a -> Maybe a
Just HandleFinalizer
handleFinalizer)
  read_side :: Handle
read_side@(FileHandle _ read_m :: MVar Handle__
read_m) <-
    String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle) -> IO Handle
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "hDuplicate" Handle
h MVar Handle__
r ((Handle__ -> IO Handle) -> IO Handle)
-> (Handle__ -> IO Handle) -> IO Handle
forall a b. (a -> b) -> a -> b
$ \h_ :: Handle__
h_ ->
        String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle String
path Handle
h (MVar Handle__ -> Maybe (MVar Handle__)
forall a. a -> Maybe a
Just MVar Handle__
write_m) Handle__
h_  Maybe HandleFinalizer
forall a. Maybe a
Nothing
  Handle -> IO Handle
forall (m :: * -> *) a. Monad m => a -> m a
return (String -> MVar Handle__ -> MVar Handle__ -> Handle
DuplexHandle String
path MVar Handle__
read_m MVar Handle__
write_m)

dupHandle :: FilePath
          -> Handle
          -> Maybe (MVar Handle__)
          -> Handle__
          -> Maybe HandleFinalizer
          -> IO Handle
dupHandle :: String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle filepath :: String
filepath h :: Handle
h other_side :: Maybe (MVar Handle__)
other_side h_ :: Handle__
h_@Handle__{..} mb_finalizer :: Maybe HandleFinalizer
mb_finalizer = do
  -- flush the buffer first, so we don't have to copy its contents
  Handle__ -> IO ()
flushBuffer Handle__
h_
  case Maybe (MVar Handle__)
other_side of
    Nothing -> do
       dev
new_dev <- dev -> IO dev
forall a. IODevice a => a -> IO a
IODevice.dup dev
haDevice
       dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
forall dev.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle_ dev
new_dev String
filepath Maybe (MVar Handle__)
other_side Handle__
h_ Maybe HandleFinalizer
mb_finalizer
    Just r :: MVar Handle__
r  ->
       String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle) -> IO Handle
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "dupHandle" Handle
h MVar Handle__
r ((Handle__ -> IO Handle) -> IO Handle)
-> (Handle__ -> IO Handle) -> IO Handle
forall a b. (a -> b) -> a -> b
$ \Handle__{haDevice :: ()
haDevice=dev
dev} -> do
         dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
forall dev.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle_ dev
dev String
filepath Maybe (MVar Handle__)
other_side Handle__
h_ Maybe HandleFinalizer
mb_finalizer

dupHandle_ :: (IODevice dev, BufferedIO dev, Typeable dev) => dev
           -> FilePath
           -> Maybe (MVar Handle__)
           -> Handle__
           -> Maybe HandleFinalizer
           -> IO Handle
dupHandle_ :: dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle_ new_dev :: dev
new_dev filepath :: String
filepath other_side :: Maybe (MVar Handle__)
other_side h_ :: Handle__
h_@Handle__{..} mb_finalizer :: Maybe HandleFinalizer
mb_finalizer = do
   -- XXX wrong!
  Maybe TextEncoding
mb_codec <- if Maybe (TextEncoder enc_state) -> Bool
forall a. Maybe a -> Bool
isJust Maybe (TextEncoder enc_state)
haEncoder then (TextEncoding -> Maybe TextEncoding)
-> IO TextEncoding -> IO (Maybe TextEncoding)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap TextEncoding -> Maybe TextEncoding
forall a. a -> Maybe a
Just IO TextEncoding
getLocaleEncoding else Maybe TextEncoding -> IO (Maybe TextEncoding)
forall (m :: * -> *) a. Monad m => a -> m a
return Maybe TextEncoding
forall a. Maybe a
Nothing
  dev
-> String
-> HandleType
-> Bool
-> Maybe TextEncoding
-> NewlineMode
-> Maybe HandleFinalizer
-> Maybe (MVar Handle__)
-> IO Handle
forall dev.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> String
-> HandleType
-> Bool
-> Maybe TextEncoding
-> NewlineMode
-> Maybe HandleFinalizer
-> Maybe (MVar Handle__)
-> IO Handle
mkHandle dev
new_dev String
filepath HandleType
haType Bool
True{-buffered-} Maybe TextEncoding
mb_codec
      NewlineMode :: Newline -> Newline -> NewlineMode
NewlineMode { inputNL :: Newline
inputNL = Newline
haInputNL, outputNL :: Newline
outputNL = Newline
haOutputNL }
      Maybe HandleFinalizer
mb_finalizer Maybe (MVar Handle__)
other_side

-- -----------------------------------------------------------------------------
-- Replacing a Handle

{- |
Makes the second handle a duplicate of the first handle.  The second
handle will be closed first, if it is not already.

This can be used to retarget the standard Handles, for example:

> do h <- openFile "mystdout" WriteMode
>    hDuplicateTo h stdout
-}

hDuplicateTo :: Handle -> Handle -> IO ()
hDuplicateTo :: Handle -> Handle -> IO ()
hDuplicateTo h1 :: Handle
h1@(FileHandle path :: String
path m1 :: MVar Handle__
m1) h2 :: Handle
h2@(FileHandle _ m2 :: MVar Handle__
m2)  = do
 String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle__) -> IO ()
withHandle__' "hDuplicateTo" Handle
h2 MVar Handle__
m2 ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \h2_ :: Handle__
h2_ -> do
   (Handle__, Maybe SomeException)
_ <- Handle__ -> IO (Handle__, Maybe SomeException)
hClose_help Handle__
h2_
   String
-> Handle
-> MVar Handle__
-> (Handle__ -> IO Handle__)
-> IO Handle__
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "hDuplicateTo" Handle
h1 MVar Handle__
m1 ((Handle__ -> IO Handle__) -> IO Handle__)
-> (Handle__ -> IO Handle__) -> IO Handle__
forall a b. (a -> b) -> a -> b
$ \h1_ :: Handle__
h1_ -> do
     String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle__
dupHandleTo String
path Handle
h1 Maybe (MVar Handle__)
forall a. Maybe a
Nothing Handle__
h2_ Handle__
h1_ (HandleFinalizer -> Maybe HandleFinalizer
forall a. a -> Maybe a
Just HandleFinalizer
handleFinalizer)
hDuplicateTo h1 :: Handle
h1@(DuplexHandle path :: String
path r1 :: MVar Handle__
r1 w1 :: MVar Handle__
w1) h2 :: Handle
h2@(DuplexHandle _ r2 :: MVar Handle__
r2 w2 :: MVar Handle__
w2)  = do
 String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle__) -> IO ()
withHandle__' "hDuplicateTo" Handle
h2 MVar Handle__
w2  ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \w2_ :: Handle__
w2_ -> do
   (Handle__, Maybe SomeException)
_ <- Handle__ -> IO (Handle__, Maybe SomeException)
hClose_help Handle__
w2_
   String
-> Handle
-> MVar Handle__
-> (Handle__ -> IO Handle__)
-> IO Handle__
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "hDuplicateTo" Handle
h1 MVar Handle__
w1 ((Handle__ -> IO Handle__) -> IO Handle__)
-> (Handle__ -> IO Handle__) -> IO Handle__
forall a b. (a -> b) -> a -> b
$ \w1_ :: Handle__
w1_ -> do
     String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle__
dupHandleTo String
path Handle
h1 Maybe (MVar Handle__)
forall a. Maybe a
Nothing Handle__
w2_ Handle__
w1_ (HandleFinalizer -> Maybe HandleFinalizer
forall a. a -> Maybe a
Just HandleFinalizer
handleFinalizer)
 String
-> Handle -> MVar Handle__ -> (Handle__ -> IO Handle__) -> IO ()
withHandle__' "hDuplicateTo" Handle
h2 MVar Handle__
r2  ((Handle__ -> IO Handle__) -> IO ())
-> (Handle__ -> IO Handle__) -> IO ()
forall a b. (a -> b) -> a -> b
$ \r2_ :: Handle__
r2_ -> do
   (Handle__, Maybe SomeException)
_ <- Handle__ -> IO (Handle__, Maybe SomeException)
hClose_help Handle__
r2_
   String
-> Handle
-> MVar Handle__
-> (Handle__ -> IO Handle__)
-> IO Handle__
forall a.
String -> Handle -> MVar Handle__ -> (Handle__ -> IO a) -> IO a
withHandle_' "hDuplicateTo" Handle
h1 MVar Handle__
r1 ((Handle__ -> IO Handle__) -> IO Handle__)
-> (Handle__ -> IO Handle__) -> IO Handle__
forall a b. (a -> b) -> a -> b
$ \r1_ :: Handle__
r1_ -> do
     String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle__
dupHandleTo String
path Handle
h1 (MVar Handle__ -> Maybe (MVar Handle__)
forall a. a -> Maybe a
Just MVar Handle__
w1) Handle__
r2_ Handle__
r1_ Maybe HandleFinalizer
forall a. Maybe a
Nothing
hDuplicateTo h1 :: Handle
h1 _ =
  Handle -> IO ()
forall a. Handle -> IO a
ioe_dupHandlesNotCompatible Handle
h1


ioe_dupHandlesNotCompatible :: Handle -> IO a
ioe_dupHandlesNotCompatible :: Handle -> IO a
ioe_dupHandlesNotCompatible h :: Handle
h =
   IOException -> IO a
forall a. IOException -> IO a
ioException (Maybe Handle
-> IOErrorType
-> String
-> String
-> Maybe CInt
-> Maybe String
-> IOException
IOError (Handle -> Maybe Handle
forall a. a -> Maybe a
Just Handle
h) IOErrorType
IllegalOperation "hDuplicateTo"
                "handles are incompatible" Maybe CInt
forall a. Maybe a
Nothing Maybe String
forall a. Maybe a
Nothing)

dupHandleTo :: FilePath
            -> Handle
            -> Maybe (MVar Handle__)
            -> Handle__
            -> Handle__
            -> Maybe HandleFinalizer
            -> IO Handle__
dupHandleTo :: String
-> Handle
-> Maybe (MVar Handle__)
-> Handle__
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle__
dupHandleTo filepath :: String
filepath h :: Handle
h other_side :: Maybe (MVar Handle__)
other_side
            hto_ :: Handle__
hto_@Handle__{haDevice :: ()
haDevice=dev
devTo,..}
            h_ :: Handle__
h_@Handle__{haDevice :: ()
haDevice=dev
dev} mb_finalizer :: Maybe HandleFinalizer
mb_finalizer = do
  Handle__ -> IO ()
flushBuffer Handle__
h_
  case dev -> Maybe dev
forall a b. (Typeable a, Typeable b) => a -> Maybe b
cast dev
devTo of
    Nothing   -> Handle -> IO Handle__
forall a. Handle -> IO a
ioe_dupHandlesNotCompatible Handle
h
    Just dev' :: dev
dev' -> do
      dev
_ <- dev -> dev -> IO dev
forall a. IODevice a => a -> a -> IO a
IODevice.dup2 dev
dev dev
dev'
      FileHandle _ m :: MVar Handle__
m <- dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
forall dev.
(IODevice dev, BufferedIO dev, Typeable dev) =>
dev
-> String
-> Maybe (MVar Handle__)
-> Handle__
-> Maybe HandleFinalizer
-> IO Handle
dupHandle_ dev
dev' String
filepath Maybe (MVar Handle__)
other_side Handle__
h_ Maybe HandleFinalizer
mb_finalizer
      MVar Handle__ -> IO Handle__
forall a. MVar a -> IO a
takeMVar MVar Handle__
m

-- ---------------------------------------------------------------------------
-- showing Handles.
--
-- | 'hShow' is in the 'IO' monad, and gives more comprehensive output
-- than the (pure) instance of 'Show' for 'Handle'.

hShow :: Handle -> IO String
hShow :: Handle -> IO String
hShow h :: Handle
h@(FileHandle path :: String
path _) = String -> Bool -> Handle -> IO String
showHandle' String
path Bool
False Handle
h
hShow h :: Handle
h@(DuplexHandle path :: String
path _ _) = String -> Bool -> Handle -> IO String
showHandle' String
path Bool
True Handle
h

showHandle' :: String -> Bool -> Handle -> IO String
showHandle' :: String -> Bool -> Handle -> IO String
showHandle' filepath :: String
filepath is_duplex :: Bool
is_duplex h :: Handle
h =
  String -> Handle -> (Handle__ -> IO String) -> IO String
forall a. String -> Handle -> (Handle__ -> IO a) -> IO a
withHandle_ "showHandle" Handle
h ((Handle__ -> IO String) -> IO String)
-> (Handle__ -> IO String) -> IO String
forall a b. (a -> b) -> a -> b
$ \hdl_ :: Handle__
hdl_ ->
    let
     showType :: ShowS
showType | Bool
is_duplex = String -> ShowS
showString "duplex (read-write)"
              | Bool
otherwise = HandleType -> ShowS
forall a. Show a => a -> ShowS
shows (Handle__ -> HandleType
haType Handle__
hdl_)
    in
    String -> IO String
forall (m :: * -> *) a. Monad m => a -> m a
return
      (( CharBufElem -> ShowS
showChar '{' ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
.
        HandleType -> ShowS -> ShowS
showHdl (Handle__ -> HandleType
haType Handle__
hdl_)
            (String -> ShowS
showString "loc=" ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. String -> ShowS
showString String
filepath ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. CharBufElem -> ShowS
showChar ',' ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
.
             String -> ShowS
showString "type=" ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. ShowS
showType ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. CharBufElem -> ShowS
showChar ',' ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
.
             String -> ShowS
showString "buffering=" ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Buffer CharBufElem -> BufferMode -> ShowS
forall e. Buffer e -> BufferMode -> ShowS
showBufMode (IO (Buffer CharBufElem) -> Buffer CharBufElem
forall a. IO a -> a
unsafePerformIO (IORef (Buffer CharBufElem) -> IO (Buffer CharBufElem)
forall a. IORef a -> IO a
readIORef (Handle__ -> IORef (Buffer CharBufElem)
haCharBuffer Handle__
hdl_))) (Handle__ -> BufferMode
haBufferMode Handle__
hdl_) ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. String -> ShowS
showString "}" )
      ) "")
   where

    showHdl :: HandleType -> ShowS -> ShowS
    showHdl :: HandleType -> ShowS -> ShowS
showHdl ht :: HandleType
ht cont :: ShowS
cont =
       case HandleType
ht of
        ClosedHandle  -> HandleType -> ShowS
forall a. Show a => a -> ShowS
shows HandleType
ht ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. String -> ShowS
showString "}"
        _ -> ShowS
cont

    showBufMode :: Buffer e -> BufferMode -> ShowS
    showBufMode :: Buffer e -> BufferMode -> ShowS
showBufMode buf :: Buffer e
buf bmo :: BufferMode
bmo =
      case BufferMode
bmo of
        NoBuffering   -> String -> ShowS
showString "none"
        LineBuffering -> String -> ShowS
showString "line"
        BlockBuffering (Just n :: Int
n) -> String -> ShowS
showString "block " ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Bool -> ShowS -> ShowS
showParen Bool
True (Int -> ShowS
forall a. Show a => a -> ShowS
shows Int
n)
        BlockBuffering Nothing  -> String -> ShowS
showString "block " ShowS -> ShowS -> ShowS
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Bool -> ShowS -> ShowS
showParen Bool
True (Int -> ShowS
forall a. Show a => a -> ShowS
shows Int
def)
      where
       def :: Int
       def :: Int
def = Buffer e -> Int
forall e. Buffer e -> Int
bufSize Buffer e
buf