PollFD.hs


{- |
Copyright  : Will Thompson, Iñaki García Etxebarria and Jonas Platte
License    : LGPL-2.1
Maintainer : Iñaki García Etxebarria (inaki@blueleaf.cc)

A file descriptor object.
-}

#define ENABLE_OVERLOADING (MIN_VERSION_haskell_gi_overloading(1,0,0) \
       && !defined(__HADDOCK_VERSION__))

module GI.Gst.Structs.PollFD
    ( 

-- * Exported types
    PollFD(..)                              ,
    newZeroPollFD                           ,
    noPollFD                                ,


 -- * Methods
-- ** init #method:init#

#if ENABLE_OVERLOADING
    PollFDInitMethodInfo                    ,
#endif
    pollFDInit                              ,




 -- * Properties
-- ** fd #attr:fd#
{- | a file descriptor
-}
    getPollFDFd                             ,
#if ENABLE_OVERLOADING
    pollFD_fd                               ,
#endif
    setPollFDFd                             ,




    ) where

import Data.GI.Base.ShortPrelude
import qualified Data.GI.Base.ShortPrelude as SP
import qualified Data.GI.Base.Overloading as O
import qualified Prelude as P

import qualified Data.GI.Base.Attributes as GI.Attributes
import qualified Data.GI.Base.ManagedPtr as B.ManagedPtr
import qualified Data.GI.Base.GClosure as B.GClosure
import qualified Data.GI.Base.GError as B.GError
import qualified Data.GI.Base.GVariant as B.GVariant
import qualified Data.GI.Base.GValue as B.GValue
import qualified Data.GI.Base.GParamSpec as B.GParamSpec
import qualified Data.GI.Base.CallStack as B.CallStack
import qualified Data.GI.Base.Properties as B.Properties
import qualified Data.Text as T
import qualified Data.ByteString.Char8 as B
import qualified Data.Map as Map
import qualified Foreign.Ptr as FP
import qualified GHC.OverloadedLabels as OL


-- | Memory-managed wrapper type.
newtype PollFD = PollFD (ManagedPtr PollFD)
instance WrappedPtr PollFD where
    wrappedPtrCalloc = callocBytes 8
    wrappedPtrCopy = \p -> withManagedPtr p (copyBytes 8 >=> wrapPtr PollFD)
    wrappedPtrFree = Just ptr_to_g_free

-- | Construct a `PollFD` struct initialized to zero.
newZeroPollFD :: MonadIO m => m PollFD
newZeroPollFD = liftIO $ wrappedPtrCalloc >>= wrapPtr PollFD

instance tag ~ 'AttrSet => Constructible PollFD tag where
    new _ attrs = do
        o <- newZeroPollFD
        GI.Attributes.set o attrs
        return o


-- | A convenience alias for `Nothing` :: `Maybe` `PollFD`.
noPollFD :: Maybe PollFD
noPollFD = Nothing

{- |
Get the value of the “@fd@” field.
When <https://github.com/haskell-gi/haskell-gi/wiki/Overloading overloading> is enabled, this is equivalent to

@
'Data.GI.Base.Attributes.get' pollFD #fd
@
-}
getPollFDFd :: MonadIO m => PollFD -> m Int32
getPollFDFd s = liftIO $ withManagedPtr s $ \ptr -> do
    val <- peek (ptr `plusPtr` 0) :: IO Int32
    return val

{- |
Set the value of the “@fd@” field.
When <https://github.com/haskell-gi/haskell-gi/wiki/Overloading overloading> is enabled, this is equivalent to

@
'Data.GI.Base.Attributes.set' pollFD [ #fd 'Data.GI.Base.Attributes.:=' value ]
@
-}
setPollFDFd :: MonadIO m => PollFD -> Int32 -> m ()
setPollFDFd s val = liftIO $ withManagedPtr s $ \ptr -> do
    poke (ptr `plusPtr` 0) (val :: Int32)

#if ENABLE_OVERLOADING
data PollFDFdFieldInfo
instance AttrInfo PollFDFdFieldInfo where
    type AttrAllowedOps PollFDFdFieldInfo = '[ 'AttrSet, 'AttrGet]
    type AttrSetTypeConstraint PollFDFdFieldInfo = (~) Int32
    type AttrBaseTypeConstraint PollFDFdFieldInfo = (~) PollFD
    type AttrGetType PollFDFdFieldInfo = Int32
    type AttrLabel PollFDFdFieldInfo = "fd"
    type AttrOrigin PollFDFdFieldInfo = PollFD
    attrGet _ = getPollFDFd
    attrSet _ = setPollFDFd
    attrConstruct = undefined
    attrClear _ = undefined

pollFD_fd :: AttrLabelProxy "fd"
pollFD_fd = AttrLabelProxy

#endif



#if ENABLE_OVERLOADING
instance O.HasAttributeList PollFD
type instance O.AttributeList PollFD = PollFDAttributeList
type PollFDAttributeList = ('[ '("fd", PollFDFdFieldInfo)] :: [(Symbol, *)])
#endif

-- method PollFD::init
-- method type : OrdinaryMethod
-- Args : [Arg {argCName = "fd", argType = TInterface (Name {namespace = "Gst", name = "PollFD"}), direction = DirectionIn, mayBeNull = False, argDoc = Documentation {rawDocText = Just "a #GstPollFD", sinceVersion = Nothing}, argScope = ScopeTypeInvalid, argClosure = -1, argDestroy = -1, argCallerAllocates = False, transfer = TransferNothing}]
-- Lengths : []
-- returnType : Nothing
-- throws : False
-- Skip return : False

foreign import ccall "gst_poll_fd_init" gst_poll_fd_init :: 
    Ptr PollFD ->                           -- fd : TInterface (Name {namespace = "Gst", name = "PollFD"})
    IO ()

{- |
Initializes /@fd@/. Alternatively you can initialize it with
@/GST_POLL_FD_INIT/@.
-}
pollFDInit ::
    (B.CallStack.HasCallStack, MonadIO m) =>
    PollFD
    {- ^ /@fd@/: a 'GI.Gst.Structs.PollFD.PollFD' -}
    -> m ()
pollFDInit fd = liftIO $ do
    fd' <- unsafeManagedPtrGetPtr fd
    gst_poll_fd_init fd'
    touchManagedPtr fd
    return ()

#if ENABLE_OVERLOADING
data PollFDInitMethodInfo
instance (signature ~ (m ()), MonadIO m) => O.MethodInfo PollFDInitMethodInfo PollFD signature where
    overloadedMethod _ = pollFDInit

#endif

#if ENABLE_OVERLOADING
type family ResolvePollFDMethod (t :: Symbol) (o :: *) :: * where
    ResolvePollFDMethod "init" o = PollFDInitMethodInfo
    ResolvePollFDMethod l o = O.MethodResolutionFailed l o

instance (info ~ ResolvePollFDMethod t PollFD, O.MethodInfo info PollFD p) => OL.IsLabel t (PollFD -> p) where
#if MIN_VERSION_base(4,10,0)
    fromLabel = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
#else
    fromLabel _ = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
#endif

#endif