{-# LINE 1 "System/Posix/Fcntl.hsc" #-}
{-# LANGUAGE CApiFFI #-}

{-# LINE 3 "System/Posix/Fcntl.hsc" #-}
{-# LANGUAGE Safe #-}

{-# LINE 7 "System/Posix/Fcntl.hsc" #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  System.Posix.Fcntl
-- Copyright   :  (c) The University of Glasgow 2014
-- License     :  BSD-style (see the file LICENSE)
--
-- Maintainer  :  libraries@haskell.org
-- Stability   :  provisional
-- Portability :  non-portable (requires POSIX)
--
-- POSIX file control support
--
-- @since 2.7.1.0
-----------------------------------------------------------------------------



module System.Posix.Fcntl (
    -- * File allocation
    Advice(..), fileAdvise,
    fileAllocate,
  ) where


{-# LINE 33 "System/Posix/Fcntl.hsc" #-}
import System.Posix.Types


{-# LINE 36 "System/Posix/Fcntl.hsc" #-}
import System.IO.Error ( ioeSetLocation )
import GHC.IO.Exception ( unsupportedOperation )

{-# LINE 39 "System/Posix/Fcntl.hsc" #-}

-- -----------------------------------------------------------------------------
-- File control

-- | Advice parameter for 'fileAdvise' operation.
--
-- For more details, see documentation of @posix_fadvise(2)@.
--
-- @since 2.7.1.0
data Advice
  = AdviceNormal
  | AdviceRandom
  | AdviceSequential
  | AdviceWillNeed
  | AdviceDontNeed
  | AdviceNoReuse
  deriving Eq

-- | Performs @posix_fadvise(2)@ operation on file-descriptor.
--
-- If platform does not provide @posix_fadvise(2)@ 'fileAdvise'
-- becomes a no-op.
--
-- (use @#if HAVE_POSIX_FADVISE@ CPP guard to detect availability)
--
-- @since 2.7.1.0
fileAdvise :: Fd -> FileOffset -> FileOffset -> Advice -> IO ()

{-# LINE 81 "System/Posix/Fcntl.hsc" #-}
fileAdvise _ _ _ _ = return ()

{-# LINE 83 "System/Posix/Fcntl.hsc" #-}

-- | Performs @posix_fallocate(2)@ operation on file-descriptor.
--
-- Throws 'IOError' (\"unsupported operation\") if platform does not
-- provide @posix_fallocate(2)@.
--
-- (use @#if HAVE_POSIX_FALLOCATE@ CPP guard to detect availability).
--
-- @since 2.7.1.0
fileAllocate :: Fd -> FileOffset -> FileOffset -> IO ()

{-# LINE 100 "System/Posix/Fcntl.hsc" #-}
{-# WARNING fileAllocate
    "operation will throw 'IOError' \"unsupported operation\" (CPP guard: @#if HAVE_POSIX_FALLOCATE@)" #-}
fileAllocate _ _ _ = ioError (ioeSetLocation unsupportedOperation
                              "fileAllocate")

{-# LINE 105 "System/Posix/Fcntl.hsc" #-}