{-# LANGUAGE CPP #-}
{-# OPTIONS_HADDOCK hide #-}

module Distribution.Compat.Internal.TempFile
  ( openTempFile
  , openBinaryTempFile
  , openNewBinaryFile
  , createTempDirectory
  ) where

import Distribution.Compat.Exception

import System.FilePath ((</>))

import System.IO (Handle, openBinaryTempFile, openTempFile)
#if defined(__IO_MANAGER_WINIO__)
import System.IO              (openBinaryTempFileWithDefaultPermissions)
#else
import Control.Exception      (onException)
import Data.Bits              ((.|.))
import Foreign.C              (CInt, eEXIST, getErrno, errnoToIOError)
import GHC.IO.Handle.FD       (fdToHandle)
import System.Posix.Internals (c_open, c_close, o_EXCL, o_BINARY, withFilePath,
                               o_CREAT, o_RDWR, o_NONBLOCK, o_NOCTTY)
#endif

import System.IO.Error (isAlreadyExistsError)
import System.Posix.Internals (c_getpid)

#if defined(mingw32_HOST_OS) || defined(ghcjs_HOST_OS)
import System.Directory       ( createDirectory )
#else
import qualified System.Posix
#endif

-- ------------------------------------------------------------

-- * temporary files

-- ------------------------------------------------------------

-- This is here for Haskell implementations that do not come with
-- System.IO.openTempFile. This includes nhc-1.20, hugs-2006.9.
-- TODO: This file should probably be removed.

-- This is a copy/paste of the openBinaryTempFile definition, but
-- it uses 666 rather than 600 for the permissions. Newer versions
-- of base have a new function with this behavior which we use on
-- Windows when the new IO manager is used.
openNewBinaryFile :: FilePath -> String -> IO (FilePath, Handle)
openNewBinaryFile :: FilePath -> FilePath -> IO (FilePath, Handle)
openNewBinaryFile FilePath
dir FilePath
template = do

-- This method can't be used under WINIO. Also the current implementation has
-- thread safety issues depending on which GHC is used.  On newer GHC's let's
-- use the built in one.
#if defined(__IO_MANAGER_WINIO__)
  openBinaryTempFileWithDefaultPermissions dir template
#else
  pid <- IO CPid
c_getpid
  findTempName pid
  where
    -- We split off the last extension, so we can use .foo.ext files
    -- for temporary files (hidden on Unix OSes). Unfortunately we're
    -- below file path in the hierarchy here.
    (FilePath
prefix,FilePath
suffix) =
       case (Char -> Bool) -> FilePath -> (FilePath, FilePath)
forall a. (a -> Bool) -> [a] -> ([a], [a])
break (Char -> Char -> Bool
forall a. Eq a => a -> a -> Bool
== Char
'.') (FilePath -> (FilePath, FilePath))
-> FilePath -> (FilePath, FilePath)
forall a b. (a -> b) -> a -> b
$ FilePath -> FilePath
forall a. [a] -> [a]
reverse FilePath
template of
         -- First case: template contains no '.'s. Just re-reverse it.
         (FilePath
rev_suffix, FilePath
"")       -> (FilePath -> FilePath
forall a. [a] -> [a]
reverse FilePath
rev_suffix, FilePath
"")
         -- Second case: template contains at least one '.'. Strip the
         -- dot from the prefix and prepend it to the suffix (if we don't
         -- do this, the unique number will get added after the '.' and
         -- thus be part of the extension, which is wrong.)
         (FilePath
rev_suffix, Char
'.':FilePath
rest) -> (FilePath -> FilePath
forall a. [a] -> [a]
reverse FilePath
rest, Char
'.'Char -> FilePath -> FilePath
forall a. a -> [a] -> [a]
:FilePath -> FilePath
forall a. [a] -> [a]
reverse FilePath
rev_suffix)
         -- Otherwise, something is wrong, because (break (== '.')) should
         -- always return a pair with either the empty string or a string
         -- beginning with '.' as the second component.
         (FilePath, FilePath)
_                      -> FilePath -> (FilePath, FilePath)
forall a. HasCallStack => FilePath -> a
error FilePath
"bug in System.IO.openTempFile"

    oflags :: CInt
oflags = CInt
rw_flags CInt -> CInt -> CInt
forall a. Bits a => a -> a -> a
.|. CInt
o_EXCL CInt -> CInt -> CInt
forall a. Bits a => a -> a -> a
.|. CInt
o_BINARY

    findTempName :: t -> IO (FilePath, Handle)
findTempName t
x = do
      fd <- FilePath -> (CString -> IO CInt) -> IO CInt
forall a. FilePath -> (CString -> IO a) -> IO a
withFilePath FilePath
filepath ((CString -> IO CInt) -> IO CInt)
-> (CString -> IO CInt) -> IO CInt
forall a b. (a -> b) -> a -> b
$ \ CString
f ->
              CString -> CInt -> FileMode -> IO CInt
c_open CString
f CInt
oflags FileMode
0o666
      if fd < 0
       then do
         errno <- getErrno
         if errno == eEXIST
           then findTempName (x+1)
           else ioError (errnoToIOError "openNewBinaryFile" errno Nothing (Just dir))
       else do
         -- TODO: We want to tell fdToHandle what the file path is,
         -- as any exceptions etc will only be able to report the
         -- FD currently
         h <- fdToHandle fd `onException` c_close fd
         return (filepath, h)
      where
        filename :: FilePath
filename        = FilePath
prefix FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ t -> FilePath
forall a. Show a => a -> FilePath
show t
x FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ FilePath
suffix
        filepath :: FilePath
filepath        = FilePath
dir FilePath -> FilePath -> FilePath
`combine` FilePath
filename

        -- FIXME: bits copied from System.FilePath
        combine :: FilePath -> FilePath -> FilePath
combine FilePath
a FilePath
b
                  | FilePath -> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null FilePath
b = FilePath
a
                  | FilePath -> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null FilePath
a = FilePath
b
                  | FilePath -> Char
forall a. HasCallStack => [a] -> a
last FilePath
a Char -> Char -> Bool
forall a. Eq a => a -> a -> Bool
== Char
pathSeparator = FilePath
a FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ FilePath
b
                  | Bool
otherwise = FilePath
a FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ [Char
pathSeparator] FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ FilePath
b

-- FIXME: Copied from GHC.Handle
std_flags, output_flags, rw_flags :: CInt
std_flags :: CInt
std_flags    = CInt
o_NONBLOCK   CInt -> CInt -> CInt
forall a. Bits a => a -> a -> a
.|. CInt
o_NOCTTY
output_flags :: CInt
output_flags = CInt
std_flags    CInt -> CInt -> CInt
forall a. Bits a => a -> a -> a
.|. CInt
o_CREAT
rw_flags :: CInt
rw_flags     = CInt
output_flags CInt -> CInt -> CInt
forall a. Bits a => a -> a -> a
.|. CInt
o_RDWR

-- FIXME: Should use System.FilePath library
pathSeparator :: Char
#ifdef mingw32_HOST_OS
pathSeparator = '\\'
#else
pathSeparator :: Char
pathSeparator = Char
'/'
#endif
-- /* __IO_MANAGER_WINIO__ */
#endif

createTempDirectory :: FilePath -> String -> IO FilePath
createTempDirectory :: FilePath -> FilePath -> IO FilePath
createTempDirectory FilePath
dir FilePath
template = do
  pid <- IO CPid
c_getpid
  findTempName pid
  where
    findTempName :: t -> IO FilePath
findTempName t
x = do
      let relpath :: FilePath
relpath = FilePath
template FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ FilePath
"-" FilePath -> FilePath -> FilePath
forall a. [a] -> [a] -> [a]
++ t -> FilePath
forall a. Show a => a -> FilePath
show t
x
          dirpath :: FilePath
dirpath = FilePath
dir FilePath -> FilePath -> FilePath
</> FilePath
relpath
      r <- IO () -> IO (Either IOError ())
forall a. IO a -> IO (Either IOError a)
tryIO (IO () -> IO (Either IOError ()))
-> IO () -> IO (Either IOError ())
forall a b. (a -> b) -> a -> b
$ FilePath -> IO ()
mkPrivateDir FilePath
dirpath
      case r of
        Right ()
_ -> FilePath -> IO FilePath
forall a. a -> IO a
forall (m :: * -> *) a. Monad m => a -> m a
return FilePath
relpath
        Left IOError
e
          | IOError -> Bool
isAlreadyExistsError IOError
e -> t -> IO FilePath
findTempName (t
x t -> t -> t
forall a. Num a => a -> a -> a
+ t
1)
          | Bool
otherwise -> IOError -> IO FilePath
forall a. HasCallStack => IOError -> IO a
ioError IOError
e

mkPrivateDir :: String -> IO ()
#if defined(mingw32_HOST_OS) || defined(ghcjs_HOST_OS)
mkPrivateDir s = createDirectory s
#else
mkPrivateDir :: FilePath -> IO ()
mkPrivateDir FilePath
s = FilePath -> FileMode -> IO ()
System.Posix.createDirectory FilePath
s FileMode
0o700
#endif