Copyright	(c) Dong Han 2020
License	BSD
Maintainer	winterland1989@gmail.com
Stability	experimental
Portability	non-portable
Safe Haskell	None
Language	Haskell2010

Z.Foreign.CPtr

Contents

CPtr type
Ptr type

Description

This module provide a lightweight foreign pointer, support c initializer and finalizer only.

Synopsis

data CPtr a
newCPtr' :: IO (Ptr a) -> FunPtr (Ptr a -> IO b) -> IO (CPtr a)
newCPtrUnsafe :: (MutableByteArray# RealWorld -> IO r) -> FunPtr (Ptr a -> IO b) -> IO (CPtr a, r)
newCPtr :: (Ptr (Ptr a) -> IO r) -> FunPtr (Ptr a -> IO b) -> IO (CPtr a, r)
withCPtr :: CPtr a -> (Ptr a -> IO b) -> IO b
withCPtrsUnsafe :: forall a b. [CPtr a] -> (BA# (Ptr a) -> Int -> IO b) -> IO b
withCPtrs :: forall a b. [CPtr a] -> (Ptr (Ptr a) -> Int -> IO b) -> IO b
data Ptr a
nullPtr :: Ptr a
data FunPtr a

CPtr type

data CPtr a Source #

Lightweight foreign pointers.

Instances

Instances details

Eq (CPtr a) Source #
Instance details Defined in Z.Foreign.CPtr Methods (==) :: CPtr a -> CPtr a -> Bool # (/=) :: CPtr a -> CPtr a -> Bool #
Ord (CPtr a) Source #
Instance details Defined in Z.Foreign.CPtr Methods compare :: CPtr a -> CPtr a -> Ordering # (<) :: CPtr a -> CPtr a -> Bool # (<=) :: CPtr a -> CPtr a -> Bool # (>) :: CPtr a -> CPtr a -> Bool # (>=) :: CPtr a -> CPtr a -> Bool # max :: CPtr a -> CPtr a -> CPtr a # min :: CPtr a -> CPtr a -> CPtr a #
Show (CPtr a) Source #
Instance details Defined in Z.Foreign.CPtr Methods showsPrec :: Int -> CPtr a -> ShowS # show :: CPtr a -> String # showList :: [CPtr a] -> ShowS #
Print (CPtr a) Source #
Instance details Defined in Z.Foreign.CPtr Methods toUTF8BuilderP :: Int -> CPtr a -> Builder () Source #

newCPtr' Source #

Arguments

:: IO (Ptr a)	initializer
-> FunPtr (Ptr a -> IO b)	finalizer
-> IO (CPtr a)

Initialize a CPtr with initializer which return an allocated pointer.

newCPtrUnsafe Source #

Arguments

:: (MutableByteArray# RealWorld -> IO r)	initializer
-> FunPtr (Ptr a -> IO b)	finalizer
-> IO (CPtr a, r)

Initialize a CPtr with initializer(must be unsafe FFI) and finalizer.

The initializer will receive a pointer of pointer so that it can do allocation and write pointer back.

newCPtr Source #

Arguments

:: (Ptr (Ptr a) -> IO r)	initializer
-> FunPtr (Ptr a -> IO b)	finalizer
-> IO (CPtr a, r)

Initialize a CPtr with initializer and finalizer.

The initializer will receive a pointer of pointer so that it can do allocation and write pointer back.

withCPtr :: CPtr a -> (Ptr a -> IO b) -> IO b Source #

The only way to use CPtr as a Ptr in FFI is to use withCPtr.

withCPtrsUnsafe :: forall a b. [CPtr a] -> (BA# (Ptr a) -> Int -> IO b) -> IO b Source #

Pass a list of 'CPtr Foo' as foo**. USE THIS FUNCTION WITH UNSAFE FFI ONLY!

withCPtrs :: forall a b. [CPtr a] -> (Ptr (Ptr a) -> Int -> IO b) -> IO b Source #

Pass a list of 'CPtr Foo' as foo**.

Ptr type

data Ptr a #

A value of type Ptr a represents a pointer to an object, or an array of objects, which may be marshalled to or from Haskell values of type a.

The type a will often be an instance of class Storable which provides the marshalling operations. However this is not essential, and you can provide your own operations to access the pointer. For example you might write small foreign functions to get or set the fields of a C struct.

Instances

Instances details

NFData1 Ptr	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Ptr a -> () #
Generic1 (URec (Ptr ()) :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec (Ptr ())) :: k -> Type # Methods from1 :: forall (a :: k0). URec (Ptr ()) a -> Rep1 (URec (Ptr ())) a # to1 :: forall (a :: k0). Rep1 (URec (Ptr ())) a -> URec (Ptr ()) a #
Eq (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods (==) :: Ptr a -> Ptr a -> Bool # (/=) :: Ptr a -> Ptr a -> Bool #
Data a => Data (Ptr a)	Since: base-4.8.0.0
Instance details Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ptr a -> c (Ptr a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Ptr a) # toConstr :: Ptr a -> Constr # dataTypeOf :: Ptr a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Ptr a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Ptr a)) # gmapT :: (forall b. Data b => b -> b) -> Ptr a -> Ptr a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ptr a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ptr a -> r # gmapQ :: (forall d. Data d => d -> u) -> Ptr a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Ptr a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ptr a -> m (Ptr a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ptr a -> m (Ptr a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ptr a -> m (Ptr a) #
Ord (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods compare :: Ptr a -> Ptr a -> Ordering # (<) :: Ptr a -> Ptr a -> Bool # (<=) :: Ptr a -> Ptr a -> Bool # (>) :: Ptr a -> Ptr a -> Bool # (>=) :: Ptr a -> Ptr a -> Bool # max :: Ptr a -> Ptr a -> Ptr a # min :: Ptr a -> Ptr a -> Ptr a #
Show (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods showsPrec :: Int -> Ptr a -> ShowS # show :: Ptr a -> String # showList :: [Ptr a] -> ShowS #
Foldable (UAddr :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => UAddr m -> m # foldMap :: Monoid m => (a -> m) -> UAddr a -> m # foldMap' :: Monoid m => (a -> m) -> UAddr a -> m # foldr :: (a -> b -> b) -> b -> UAddr a -> b # foldr' :: (a -> b -> b) -> b -> UAddr a -> b # foldl :: (b -> a -> b) -> b -> UAddr a -> b # foldl' :: (b -> a -> b) -> b -> UAddr a -> b # foldr1 :: (a -> a -> a) -> UAddr a -> a # foldl1 :: (a -> a -> a) -> UAddr a -> a # toList :: UAddr a -> [a] # null :: UAddr a -> Bool # length :: UAddr a -> Int # elem :: Eq a => a -> UAddr a -> Bool # maximum :: Ord a => UAddr a -> a # minimum :: Ord a => UAddr a -> a # sum :: Num a => UAddr a -> a # product :: Num a => UAddr a -> a #
Traversable (UAddr :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> UAddr a -> f (UAddr b) # sequenceA :: Applicative f => UAddr (f a) -> f (UAddr a) # mapM :: Monad m => (a -> m b) -> UAddr a -> m (UAddr b) # sequence :: Monad m => UAddr (m a) -> m (UAddr a) #
NFData (Ptr a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Ptr a -> () #
Hashable (Ptr a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ptr a -> Int # hash :: Ptr a -> Int #
Prim (Ptr a)
Instance details Defined in Data.Primitive.Types Methods sizeOf# :: Ptr a -> Int# # alignment# :: Ptr a -> Int# # indexByteArray# :: ByteArray# -> Int# -> Ptr a # readByteArray# :: MutableByteArray# s -> Int# -> State# s -> (# State# s, Ptr a #) # writeByteArray# :: MutableByteArray# s -> Int# -> Ptr a -> State# s -> State# s # setByteArray# :: MutableByteArray# s -> Int# -> Int# -> Ptr a -> State# s -> State# s # indexOffAddr# :: Addr# -> Int# -> Ptr a # readOffAddr# :: Addr# -> Int# -> State# s -> (# State# s, Ptr a #) # writeOffAddr# :: Addr# -> Int# -> Ptr a -> State# s -> State# s # setOffAddr# :: Addr# -> Int# -> Int# -> Ptr a -> State# s -> State# s #
Unaligned (Ptr a) Source #
Instance details Defined in Z.Data.Array.Unaligned Methods unalignedSize :: UnalignedSize (Ptr a) Source # indexWord8ArrayAs# :: ByteArray# -> Int# -> Ptr a Source # readWord8ArrayAs# :: MutableByteArray# s -> Int# -> State# s -> (# State# s, Ptr a #) Source # writeWord8ArrayAs# :: MutableByteArray# s -> Int# -> Ptr a -> State# s -> State# s Source # peekMBA :: MutableByteArray# RealWorld -> Int -> IO (Ptr a) Source # pokeMBA :: MutableByteArray# RealWorld -> Int -> Ptr a -> IO () Source # indexBA :: ByteArray# -> Int -> Ptr a Source #
Print (Ptr a) Source #
Instance details Defined in Z.Data.Text.Print Methods toUTF8BuilderP :: Int -> Ptr a -> Builder () Source #
Functor (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec (Ptr ()) a -> URec (Ptr ()) b # (<$) :: a -> URec (Ptr ()) b -> URec (Ptr ()) a #
Eq (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (/=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #
Ord (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec (Ptr ()) p -> URec (Ptr ()) p -> Ordering # (<) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (<=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # max :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p # min :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p #
Generic (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Associated Types type Rep (URec (Ptr ()) p) :: Type -> Type # Methods from :: URec (Ptr ()) p -> Rep (URec (Ptr ()) p) x # to :: Rep (URec (Ptr ()) p) x -> URec (Ptr ()) p #
data URec (Ptr ()) (p :: k)	Used for marking occurrences of `Addr#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec (Ptr ()) (p :: k) = UAddr { uAddr# :: Addr# }
type Rep1 (URec (Ptr ()) :: k -> Type)
Instance details Defined in GHC.Generics type Rep1 (URec (Ptr ()) :: k -> Type) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UAddr" 'PrefixI 'True) (S1 ('MetaSel ('Just "uAddr#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UAddr :: k -> Type)))
type Rep (URec (Ptr ()) p)
Instance details Defined in GHC.Generics type Rep (URec (Ptr ()) p) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UAddr" 'PrefixI 'True) (S1 ('MetaSel ('Just "uAddr#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UAddr :: Type -> Type)))

nullPtr :: Ptr a #

The constant nullPtr contains a distinguished value of Ptr that is not associated with a valid memory location.

data FunPtr a #

A value of type FunPtr a is a pointer to a function callable from foreign code. The type a will normally be a foreign type, a function type with zero or more arguments where

the argument types are marshallable foreign types, i.e. Char, Int, Double, Float, Bool, Int8, Int16, Int32, Int64, Word8, Word16, Word32, Word64, Ptr a, FunPtr a, StablePtr a or a renaming of any of these using newtype.
the return type is either a marshallable foreign type or has the form IO t where t is a marshallable foreign type or ().

A value of type FunPtr a may be a pointer to a foreign function, either returned by another foreign function or imported with a a static address import like

foreign import ccall "stdlib.h &free"
  p_free :: FunPtr (Ptr a -> IO ())

or a pointer to a Haskell function created using a wrapper stub declared to produce a FunPtr of the correct type. For example:

type Compare = Int -> Int -> Bool
foreign import ccall "wrapper"
  mkCompare :: Compare -> IO (FunPtr Compare)

Calls to wrapper stubs like mkCompare allocate storage, which should be released with freeHaskellFunPtr when no longer required.

To convert FunPtr values to corresponding Haskell functions, one can define a dynamic stub for the specific foreign type, e.g.

type IntFunction = CInt -> IO ()
foreign import ccall "dynamic"
  mkFun :: FunPtr IntFunction -> IntFunction

Instances

Instances details

NFData1 FunPtr	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> FunPtr a -> () #
Eq (FunPtr a)
Instance details Defined in GHC.Ptr Methods (==) :: FunPtr a -> FunPtr a -> Bool # (/=) :: FunPtr a -> FunPtr a -> Bool #
Ord (FunPtr a)
Instance details Defined in GHC.Ptr Methods compare :: FunPtr a -> FunPtr a -> Ordering # (<) :: FunPtr a -> FunPtr a -> Bool # (<=) :: FunPtr a -> FunPtr a -> Bool # (>) :: FunPtr a -> FunPtr a -> Bool # (>=) :: FunPtr a -> FunPtr a -> Bool # max :: FunPtr a -> FunPtr a -> FunPtr a # min :: FunPtr a -> FunPtr a -> FunPtr a #
Show (FunPtr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods showsPrec :: Int -> FunPtr a -> ShowS # show :: FunPtr a -> String # showList :: [FunPtr a] -> ShowS #
NFData (FunPtr a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: FunPtr a -> () #
Hashable (FunPtr a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> FunPtr a -> Int # hash :: FunPtr a -> Int #
Prim (FunPtr a)
Instance details Defined in Data.Primitive.Types Methods sizeOf# :: FunPtr a -> Int# # alignment# :: FunPtr a -> Int# # indexByteArray# :: ByteArray# -> Int# -> FunPtr a # readByteArray# :: MutableByteArray# s -> Int# -> State# s -> (# State# s, FunPtr a #) # writeByteArray# :: MutableByteArray# s -> Int# -> FunPtr a -> State# s -> State# s # setByteArray# :: MutableByteArray# s -> Int# -> Int# -> FunPtr a -> State# s -> State# s # indexOffAddr# :: Addr# -> Int# -> FunPtr a # readOffAddr# :: Addr# -> Int# -> State# s -> (# State# s, FunPtr a #) # writeOffAddr# :: Addr# -> Int# -> FunPtr a -> State# s -> State# s # setOffAddr# :: Addr# -> Int# -> Int# -> FunPtr a -> State# s -> State# s #