ref: 7d6f6cd4091dc045928a6cfad514d5f5d3eb260f
dir: /lib/Foreign/Marshal/Utils.hs/
module Foreign.Marshal.Utils(module Foreign.Marshal.Utils) where
import Prelude(); import MiniPrelude
import Foreign.Marshal.Alloc
import Foreign.C.Types
import Foreign.Ptr
import Foreign.Storable
new :: forall a . Storable a => a -> IO (Ptr a)
new val = do
ptr <- malloc
poke ptr val
return ptr
with :: forall a b . Storable a => a -> (Ptr a -> IO b) -> IO b
with val f =
alloca $ \ ptr -> do
poke ptr val
f ptr
fromBool :: forall a . Num a => Bool -> a
fromBool False = 0
fromBool True = 1
toBool :: forall a . (Eq a, Num a) => a -> Bool
toBool = (/= 0)
maybeNew :: forall a b .
( a -> IO (Ptr b))
-> (Maybe a -> IO (Ptr b))
maybeNew = maybe (return nullPtr)
maybeWith :: forall a b c .
( a -> (Ptr b -> IO c) -> IO c)
-> (Maybe a -> (Ptr b -> IO c) -> IO c)
maybeWith = maybe ($ nullPtr)
maybePeek :: forall a b . (Ptr a -> IO b) -> Ptr a -> IO (Maybe b)
maybePeek peek ptr | ptr == nullPtr = return Nothing
| otherwise = do { a <- peek ptr; return (Just a) }
withMany :: forall a b res .
(a -> (b -> res) -> res)
-> [a]
-> ([b] -> res)
-> res
withMany _ [] f = f []
withMany wth (x : xs) f =
wth x $ \ x' ->
withMany wth xs (\ xs' -> f (x' : xs'))
foreign import ccall "memcpy" c_memcpy :: Ptr () -> Ptr () -> CSize -> IO ()
foreign import ccall "memmove" c_memmove :: Ptr () -> Ptr () -> CSize -> IO ()
copyBytes :: forall a b . Ptr a -> Ptr a -> Int -> IO ()
copyBytes p q i = c_memcpy (castPtr p) (castPtr q) (intToCSize i)
moveBytes :: forall a b . Ptr a -> Ptr a -> Int -> IO ()
moveBytes p q i = c_memmove (castPtr p) (castPtr q) (intToCSize i)