{-# language BangPatterns #-}
{-# language MagicHash #-}
{-# language UnliftedFFITypes #-}
{-# language ScopedTypeVariables #-}
module Posix.Poll
( uninterruptiblePoll
, uninterruptiblePollMutablePrimArray
, PollFd(..)
, Exchange(..)
, PT.input
, PT.output
, PT.error
, PT.hangup
, PT.invalid
, PT.isSubeventOf
) where
import Posix.Types (CNfds(..))
import Foreign.C.Error (Errno,getErrno)
import Foreign.C.Types (CInt(..))
import GHC.Ptr (Ptr)
import GHC.Exts (RealWorld,MutableByteArray#)
import Posix.Poll.Types (PollFd(..),Exchange(..))
import Data.Primitive (MutablePrimArray(..))
import Data.Word (Word64)
import qualified Posix.Poll.Types as PT
foreign import ccall unsafe "poll.h poll"
c_poll_ptr :: Ptr PollFd -> CNfds -> CInt -> IO CInt
foreign import ccall unsafe "poll.h poll"
c_poll_prim_array :: MutableByteArray# RealWorld -> CNfds -> CInt -> IO CInt
uninterruptiblePoll ::
Ptr PollFd
-> CNfds
-> IO (Either Errno CInt)
uninterruptiblePoll pfds n =
c_poll_ptr pfds n 0 >>= errorsFromInt
uninterruptiblePollMutablePrimArray ::
MutablePrimArray RealWorld PollFd
-> CNfds
-> IO (Either Errno CInt)
uninterruptiblePollMutablePrimArray (MutablePrimArray pfds) n =
c_poll_prim_array pfds n 0 >>= errorsFromInt
errorsFromInt :: CInt -> IO (Either Errno CInt)
errorsFromInt r = if r >= 0
then pure (Right r)
else fmap Left getErrno