CloseOnExec.hs

{- This is a subset of the functions provided by file-io.
 -
 - All functions have been modified to set the close-on-exec
 - flag to True.
 -
 - Copyright 2025-2026 Joey Hess <id@joeyh.name>
 - Copyright 2024 Julian Ospald
 -
 - License: BSD-3-clause
 -}

{-# OPTIONS_GHC -fno-warn-tabs #-}
{-# LANGUAGE CPP #-}
{-# LANGUAGE NoImplicitPrelude #-}

module Utility.FileIO.CloseOnExec
(
#ifdef WITH_OSPATH
	withFile,
	withFile',
	openFile,
	withBinaryFile,
	openBinaryFile,
	readFile,
	readFile',
	writeFile,
	writeFile',
	appendFile,
	appendFile',
	openTempFile,
#endif
) where

#ifdef WITH_OSPATH

import System.File.OsPath.Internal (withOpenFile', augmentError)
import qualified System.File.OsPath.Internal as I
import System.IO (IO, Handle, IOMode(..))
import System.OsPath (OsPath, OsString)
import Prelude (Bool(..), pure, either, (.), (>>=), ($))
import Control.Exception
import qualified Data.ByteString as BS
import qualified Data.ByteString.Lazy as BSL

closeOnExec :: Bool
closeOnExec = True

withFile :: OsPath -> IOMode -> (Handle -> IO r) -> IO r
withFile osfp iomode act = (augmentError "withFile" osfp
    $ withOpenFile' osfp iomode False False closeOnExec (try . act) True)
  >>= either ioError pure

withFile' :: OsPath -> IOMode -> (Handle -> IO r) -> IO r
withFile' osfp iomode act = (augmentError "withFile'" osfp
    $ withOpenFile' osfp iomode False False closeOnExec (try . act) False)
  >>= either ioError pure

openFile :: OsPath -> IOMode -> IO Handle
openFile osfp iomode =  augmentError "openFile" osfp $
	withOpenFile' osfp iomode False False closeOnExec pure False

withBinaryFile :: OsPath -> IOMode -> (Handle -> IO r) -> IO r
withBinaryFile osfp iomode act = (augmentError "withBinaryFile" osfp
    $ withOpenFile' osfp iomode True False closeOnExec (try . act) True)
  >>= either ioError pure

openBinaryFile :: OsPath -> IOMode -> IO Handle
openBinaryFile osfp iomode = augmentError "openBinaryFile" osfp $
	 withOpenFile' osfp iomode True False closeOnExec pure False

readFile :: OsPath -> IO BSL.ByteString
readFile fp = withFile' fp ReadMode BSL.hGetContents

readFile' :: OsPath -> IO BS.ByteString
readFile' fp = withFile fp ReadMode BS.hGetContents

writeFile :: OsPath -> BSL.ByteString -> IO ()
writeFile fp contents = withFile fp WriteMode (`BSL.hPut` contents)

writeFile' :: OsPath -> BS.ByteString -> IO ()
writeFile' fp contents = withFile fp WriteMode (`BS.hPut` contents)

appendFile :: OsPath -> BSL.ByteString -> IO ()
appendFile fp contents = withFile fp AppendMode (`BSL.hPut` contents)

appendFile' :: OsPath -> BS.ByteString -> IO ()
appendFile' fp contents = withFile fp AppendMode (`BS.hPut` contents)

openTempFile :: OsPath -> OsString -> IO (OsPath, Handle)
openTempFile tmp_dir template =
	I.openTempFile' "openTempFile" tmp_dir template False 0o600 closeOnExec
#endif