1 % ------------------------------------------------------------------------------
2 % $Id: PrelForeign.lhs,v 1.17 2001/01/11 17:25:57 simonmar Exp $
4 % (c) The University of Glasgow, 1994-2000
7 \section[Foreign]{Module @Foreign@}
10 {-# OPTIONS -fno-implicit-prelude #-}
12 module PrelForeign where
19 %*********************************************************
21 \subsection{ForeignPtr}
23 %*********************************************************
26 #ifndef __PARALLEL_HASKELL__
27 newForeignPtr :: Ptr a -> IO () -> IO (ForeignPtr a)
28 newForeignPtr p finalizer
29 = do fObj <- mkForeignPtr p
30 addForeignPtrFinalizer fObj finalizer
33 addForeignPtrFinalizer :: ForeignPtr a -> IO () -> IO ()
34 addForeignPtrFinalizer (ForeignPtr fo) finalizer =
35 IO $ \s -> case mkWeak# fo () finalizer s of { (# s1, w #) -> (# s1, () #) }
37 mkForeignPtr :: Ptr a -> IO (ForeignPtr a) {- not exported -}
38 mkForeignPtr (Ptr obj) = IO ( \ s# ->
39 case mkForeignObj# obj s# of
40 (# s1#, fo# #) -> (# s1#, ForeignPtr fo# #) )
42 touchForeignPtr :: ForeignPtr a -> IO ()
43 touchForeignPtr (ForeignPtr fo)
44 = IO $ \s -> case touch# fo s of s -> (# s, () #)
46 withForeignPtr :: ForeignPtr a -> (Ptr a -> IO b) -> IO b
48 = do r <- io (foreignPtrToPtr fo)
52 foreignPtrToPtr :: ForeignPtr a -> Ptr a
53 foreignPtrToPtr (ForeignPtr fo) = Ptr (foreignObjToAddr# fo)
55 castForeignPtr (ForeignPtr a) = ForeignPtr a