{-# OPTIONS_GHC -cpp -fffi #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  System.Process.Internals
-- Copyright   :  (c) The University of Glasgow 2004
-- License     :  BSD-style (see the file libraries/base/LICENSE)
-- 
-- Maintainer  :  libraries@haskell.org
-- Stability   :  experimental
-- Portability :  portable
--
-- Operations for creating and interacting with sub-processes.
--
-----------------------------------------------------------------------------

-- #hide
module System.Process.Internals (






	 pPrPr_disableITimers, c_execvpe,



	ignoreSignal, defaultSignal,








	withFilePathException, withCEnvironment
  ) where

import Prelude -- necessary to get dependencies right


import System.Posix.Types ( CPid )
import System.IO 	( Handle )





import System.Exit	( ExitCode )
import Data.Maybe	( fromMaybe )




import Hugs.Exception	( Exception(..), IOException(..) )


import Control.Concurrent
import Control.Exception ( handle, throwIO )
import Foreign.C
import Foreign












{-# CFILES cbits/execvpe.c  #-}


                                                                              
                                                                             

                         


                          


                              


                                 


                        


                                


                          


                            


                         


                           


                           


                         


                          


                         


                                


                                


                              


                           


                                


                          


                        


                          


                          


                          


                         


                          


                             


                                


                         


                          


                               


                         


                          


                       


                           


                          


                         


                          


                          


                            


                             


                                


                            


                             


                               


                          


                           


                            


                           


                          


                          


                           


                          


                           


                          


                          


                          


                               


                          


                         


                          


                          


                           


                            


                           


                             


                            


                          


                         


                              


                         


                                


                         


                            


                                


                                 


                                


                          


                                   


                              


                          


                           


                           


                         


                                


                            


                             


                                   


                          


                         


                          


                          


                         


                             


                                


                           


                          


                               


                         


                            


                           


                           


                          


                           


                           


                          


                          


                          


                          


                           


                           


                           


                           


                           


                           


                           


                          


                           


                           


                           


                           


                           


                          


                           


                           


                             


                           


                           


                             


                           


                           


                           


                               


                               


                                                        


                                                                                     


                                                                                    


                                                         


                                                        


                                                        


                                                  


                                                   


                                                       


                                                      
                          

                                                       


                                                          


                                                      


                                                           


                                                      


                                                         


                                                         


                                                         


                                                   


                                                         


                                                       


                                                       


                                                         


                                                         


                                                         


                                                          


                                                         


                                                        
                                   

                                                               


                                                             


                                                           


                                                              


                                                            


                                                             
                              

                                                            


                                                           


                                                            


                                                              


                                                           


                                                          


                                                   


                                                       


                                                                                                         
                         

                                                                                         


                                                         


                                                        


                                                   


                                                        
                         

                                                         


                                                          
                           

                                                          
                           

                                  


                                   


                                                     
                         

                                     


                                     


                                        


                                      


                                       


                                      


                                      


                                      


                                    


                                         


                                         


                                     


                                          


                                       


                                        


                                      


                                      


                                          


                                       


                                      


                                            


                                             


                                       


                                        


                                        


                                         


                                       


                                      


                                          


                                          


                                              


                                             


                                              


                                                   


                                               


                                        


                                       
                         

                                                                              


                                              


                                                          


                                                          


                                            


                                           


                                                      


                                                                           


                                                            
                           

                                                                       


                                                 
                         

                                                            
                  

                                                       
                  

                                                
                  







































































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



-- this function disables the itimer, which would otherwise cause confusing
-- signals to be sent to the new process.
foreign import ccall unsafe "pPrPr_disableITimers"
  pPrPr_disableITimers :: IO ()

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
































































ignoreSignal  = 1 :: CLong
defaultSignal = 0 :: CLong
























































































































































































-- ----------------------------------------------------------------------------
-- Utils

withFilePathException :: FilePath -> IO a -> IO a
withFilePathException fpath act = handle mapEx act
  where
    mapEx (IOException (IOError h iot fun str _)) = ioError (IOError h iot fun str (Just fpath))
    mapEx e                                       = throwIO e


withCEnvironment :: [(String,String)] -> (Ptr CString  -> IO a) -> IO a
withCEnvironment env act =
  let env' = map (\(name, val) -> name ++ ('=':val)) env 
  in withMany withCString env' (\pEnv -> withArray0 nullPtr pEnv act)