{-# LANGUAGE CApiFFI #-}
{-# LANGUAGE Trustworthy #-}

module System.Posix.Process.Internals (
       pPrPr_disableITimers, c_execvpe,
       decipherWaitStatus, ProcessStatus(..) ) where

import Foreign
import Foreign.C
import System.Exit
import System.IO.Error
import GHC.Conc (Signal)

-- | The exit status of a process
data ProcessStatus
   = Exited ExitCode        -- ^ the process exited by calling
                            -- @exit()@ or returning from @main@
   | Terminated Signal Bool -- ^ the process was terminated by a
                            -- signal, the @Bool@ is @True@ if a core
                            -- dump was produced
                            --
                            -- @since 2.7.0.0
   | Stopped Signal         -- ^ the process was stopped by a signal
   deriving (ProcessStatus -> ProcessStatus -> Bool
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-- this function disables the itimer, which would otherwise cause confusing
-- signals to be sent to the new process.
foreign import capi unsafe "Rts.h stopTimer"
  pPrPr_disableITimers :: IO ()

foreign import ccall unsafe "__hsunix_execvpe"
  c_execvpe :: CString -> Ptr CString -> Ptr CString -> IO CInt

decipherWaitStatus :: CInt -> IO ProcessStatus
decipherWaitStatus :: CInt -> IO ProcessStatus
decipherWaitStatus CInt
wstat =
  if CInt -> CInt
c_WIFEXITED CInt
wstat CInt -> CInt -> Bool
forall a. Eq a => a -> a -> Bool
/= CInt
0
      then do
        let exitstatus :: CInt
exitstatus = CInt -> CInt
c_WEXITSTATUS CInt
wstat
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      else do
        if CInt -> CInt
c_WIFSIGNALED CInt
wstat CInt -> CInt -> Bool
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termsig    = CInt -> CInt
c_WTERMSIG CInt
wstat
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coredumped = CInt -> CInt
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foreign import capi unsafe "HsUnix.h WIFEXITED"
  c_WIFEXITED :: CInt -> CInt

foreign import capi unsafe "HsUnix.h WEXITSTATUS"
  c_WEXITSTATUS :: CInt -> CInt

foreign import capi unsafe "HsUnix.h WIFSIGNALED"
  c_WIFSIGNALED :: CInt -> CInt

foreign import capi unsafe "HsUnix.h WTERMSIG"
  c_WTERMSIG :: CInt -> CInt

foreign import capi unsafe "HsUnix.h WIFSTOPPED"
  c_WIFSTOPPED :: CInt -> CInt

foreign import capi unsafe "HsUnix.h WSTOPSIG"
  c_WSTOPSIG :: CInt -> CInt

foreign import capi unsafe "HsUnix.h WCOREDUMP"
  c_WCOREDUMP :: CInt -> CInt