PollFD.hs


{- |
Copyright  : Will Thompson, Iñaki García Etxebarria and Jonas Platte
License    : LGPL-2.1
Maintainer : Iñaki García Etxebarria (garetxe@gmail.com)

Represents a file descriptor, which events to poll for, and which events
occurred.
-}

module GI.GLib.Structs.PollFD
    ( 

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


 -- * Properties
-- ** Events
    pollFDReadEvents                        ,


-- ** Fd
    pollFDReadFd                            ,


-- ** Revents
    pollFDReadRevents                       ,




    ) where

import Prelude ()
import Data.GI.Base.ShortPrelude

import qualified Data.Text as T
import qualified Data.ByteString.Char8 as B
import qualified Data.Map as Map

import GI.GLib.Types
import GI.GLib.Callbacks

newtype PollFD = PollFD (ForeignPtr PollFD)
foreign import ccall "g_pollfd_get_type" c_g_pollfd_get_type :: 
    IO GType

instance BoxedObject PollFD where
    boxedType _ = c_g_pollfd_get_type

-- | Construct a `PollFD` struct initialized to zero.
newZeroPollFD :: MonadIO m => m PollFD
newZeroPollFD = liftIO $ callocBoxedBytes 8 >>= wrapBoxed PollFD

noPollFD :: Maybe PollFD
noPollFD = Nothing

pollFDReadFd :: PollFD -> IO Int32
pollFDReadFd s = withManagedPtr s $ \ptr -> do
    val <- peek (ptr `plusPtr` 0) :: IO Int32
    return val

pollFDReadEvents :: PollFD -> IO Word16
pollFDReadEvents s = withManagedPtr s $ \ptr -> do
    val <- peek (ptr `plusPtr` 4) :: IO Word16
    return val

pollFDReadRevents :: PollFD -> IO Word16
pollFDReadRevents s = withManagedPtr s $ \ptr -> do
    val <- peek (ptr `plusPtr` 6) :: IO Word16
    return val

type family ResolvePollFDMethod (t :: Symbol) (o :: *) :: * where
    ResolvePollFDMethod l o = MethodResolutionFailed l o

instance (info ~ ResolvePollFDMethod t PollFD, MethodInfo info PollFD p) => IsLabelProxy t (PollFD -> p) where
    fromLabelProxy _ = overloadedMethod (MethodProxy :: MethodProxy info)

#if MIN_VERSION_base(4,9,0)
instance (info ~ ResolvePollFDMethod t PollFD, MethodInfo info PollFD p) => IsLabel t (PollFD -> p) where
    fromLabel _ = overloadedMethod (MethodProxy :: MethodProxy info)
#endif