{-# LANGUAGE CPP, ForeignFunctionInterface, RecordWildCards #-} {-# OPTIONS_HADDOCK hide #-} {-# OPTIONS_GHC -w #-} -- XXX We get some warnings on Windows #if __GLASGOW_HASKELL__ >= 701 {-# LANGUAGE Trustworthy #-} #endif ----------------------------------------------------------------------------- -- | -- 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 ( #ifndef __HUGS__ ProcessHandle(..), ProcessHandle__(..), PHANDLE, closePHANDLE, mkProcessHandle, withProcessHandle, withProcessHandle_, #ifdef __GLASGOW_HASKELL__ CreateProcess(..), CmdSpec(..), StdStream(..), runGenProcess_, #endif #if !defined(mingw32_HOST_OS) && !defined(__MINGW32__) pPrPr_disableITimers, c_execvpe, ignoreSignal, defaultSignal, #endif #endif withFilePathException, withCEnvironment, translate, #ifndef __HUGS__ fdToHandle, #endif ) where #ifndef __HUGS__ #if !defined(mingw32_HOST_OS) && !defined(__MINGW32__) import System.Posix.Types import System.Posix.Process.Internals ( pPrPr_disableITimers, c_execvpe ) import System.IO ( IOMode(..) ) #else import Data.Word ( Word32 ) import Data.IORef #endif #endif import System.IO ( Handle ) import System.Exit ( ExitCode ) import Control.Concurrent import Control.Exception import Foreign.C import Foreign # ifdef __GLASGOW_HASKELL__ import System.Posix.Internals #if __GLASGOW_HASKELL__ >= 611 import GHC.IO.Exception import GHC.IO.Encoding import qualified GHC.IO.FD as FD import GHC.IO.Device import GHC.IO.Handle import GHC.IO.Handle.FD import GHC.IO.Handle.Internals import GHC.IO.Handle.Types import System.IO.Error import Data.Typeable #if defined(mingw32_HOST_OS) import GHC.IO.IOMode import System.Win32.DebugApi (PHANDLE) #endif #else import GHC.IOBase ( haFD, FD, IOException(..) ) import GHC.Handle #endif # elif __HUGS__ import Hugs.Exception ( IOException(..) ) # endif #ifdef base4 import System.IO.Error ( ioeSetFileName ) #endif #if defined(mingw32_HOST_OS) import Control.Monad ( when ) import System.Directory ( doesFileExist ) import System.IO.Error ( isDoesNotExistError, doesNotExistErrorType, mkIOError ) import System.Environment ( getEnv ) import System.FilePath #endif #ifdef __HUGS__ {-# CFILES cbits/execvpe.c #-} #endif #include "HsProcessConfig.h" #include "processFlags.h" #ifndef __HUGS__ -- ---------------------------------------------------------------------------- -- ProcessHandle type {- | A handle to a process, which can be used to wait for termination of the process using 'waitForProcess'. None of the process-creation functions in this library wait for termination: they all return a 'ProcessHandle' which may be used to wait for the process later. -} data ProcessHandle__ = OpenHandle PHANDLE | ClosedHandle ExitCode newtype ProcessHandle = ProcessHandle (MVar ProcessHandle__) withProcessHandle :: ProcessHandle -> (ProcessHandle__ -> IO (ProcessHandle__, a)) -> IO a withProcessHandle (ProcessHandle m) io = modifyMVar m io withProcessHandle_ :: ProcessHandle -> (ProcessHandle__ -> IO ProcessHandle__) -> IO () withProcessHandle_ (ProcessHandle m) io = modifyMVar_ m io #if !defined(mingw32_HOST_OS) && !defined(__MINGW32__) type PHANDLE = CPid throwErrnoIfBadPHandle :: String -> IO PHANDLE -> IO PHANDLE throwErrnoIfBadPHandle = throwErrnoIfMinus1 mkProcessHandle :: PHANDLE -> IO ProcessHandle mkProcessHandle p = do m <- newMVar (OpenHandle p) return (ProcessHandle m) closePHANDLE :: PHANDLE -> IO () closePHANDLE _ = return () #else throwErrnoIfBadPHandle :: String -> IO PHANDLE -> IO PHANDLE throwErrnoIfBadPHandle = throwErrnoIfNull -- On Windows, we have to close this HANDLE when it is no longer required, -- hence we add a finalizer to it, using an IORef as the box on which to -- attach the finalizer. mkProcessHandle :: PHANDLE -> IO ProcessHandle mkProcessHandle h = do m <- newMVar (OpenHandle h) addMVarFinalizer m (processHandleFinaliser m) return (ProcessHandle m) processHandleFinaliser m = modifyMVar_ m $ \p_ -> do case p_ of OpenHandle ph -> closePHANDLE ph _ -> return () return (error "closed process handle") closePHANDLE :: PHANDLE -> IO () closePHANDLE ph = c_CloseHandle ph foreign import stdcall unsafe "CloseHandle" c_CloseHandle :: PHANDLE -> IO () #endif #endif /* !__HUGS__ */ -- ---------------------------------------------------------------------------- data CreateProcess = CreateProcess{ cmdspec :: CmdSpec, -- ^ Executable & arguments, or shell command cwd :: Maybe FilePath, -- ^ Optional path to the working directory for the new process env :: Maybe [(String,String)], -- ^ Optional environment (otherwise inherit from the current process) std_in :: StdStream, -- ^ How to determine stdin std_out :: StdStream, -- ^ How to determine stdout std_err :: StdStream, -- ^ How to determine stderr close_fds :: Bool, -- ^ Close all file descriptors except stdin, stdout and stderr in the new process (on Windows, only works if std_in, std_out, and std_err are all Inherit) create_group :: Bool -- ^ Create a new process group } data CmdSpec = ShellCommand String -- ^ a command line to execute using the shell | RawCommand FilePath [String] -- ^ the filename of an executable with a list of arguments data StdStream = Inherit -- ^ Inherit Handle from parent | UseHandle Handle -- ^ Use the supplied Handle | CreatePipe -- ^ Create a new pipe. The returned -- @Handle@ will use the default encoding -- and newline translation mode (just -- like @Handle@s created by @openFile@). runGenProcess_ :: String -- ^ function name (for error messages) -> CreateProcess -> Maybe CLong -- ^ handler for SIGINT -> Maybe CLong -- ^ handler for SIGQUIT -> IO (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) #if !defined(mingw32_HOST_OS) && !defined(__MINGW32__) #ifdef __GLASGOW_HASKELL__ -- ----------------------------------------------------------------------------- -- POSIX runProcess with signal handling in the child runGenProcess_ fun CreateProcess{ cmdspec = cmdsp, cwd = mb_cwd, env = mb_env, std_in = mb_stdin, std_out = mb_stdout, std_err = mb_stderr, close_fds = mb_close_fds, create_group = mb_create_group } mb_sigint mb_sigquit = do let (cmd,args) = commandToProcess cmdsp withFilePathException cmd $ alloca $ \ pfdStdInput -> alloca $ \ pfdStdOutput -> alloca $ \ pfdStdError -> maybeWith withCEnvironment mb_env $ \pEnv -> maybeWith withFilePath mb_cwd $ \pWorkDir -> withMany withFilePath (cmd:args) $ \cstrs -> withArray0 nullPtr cstrs $ \pargs -> do fdin <- mbFd fun fd_stdin mb_stdin fdout <- mbFd fun fd_stdout mb_stdout fderr <- mbFd fun fd_stderr mb_stderr let (set_int, inthand) = case mb_sigint of Nothing -> (0, 0) Just hand -> (1, hand) (set_quit, quithand) = case mb_sigquit of Nothing -> (0, 0) Just hand -> (1, hand) -- runInteractiveProcess() blocks signals around the fork(). -- Since blocking/unblocking of signals is a global state -- operation, we better ensure mutual exclusion of calls to -- runInteractiveProcess(). proc_handle <- withMVar runInteractiveProcess_lock $ \_ -> throwErrnoIfMinus1 fun $ c_runInteractiveProcess pargs pWorkDir pEnv fdin fdout fderr pfdStdInput pfdStdOutput pfdStdError set_int inthand set_quit quithand ((if mb_close_fds then RUN_PROCESS_IN_CLOSE_FDS else 0) .|.(if mb_create_group then RUN_PROCESS_IN_NEW_GROUP else 0)) hndStdInput <- mbPipe mb_stdin pfdStdInput WriteMode hndStdOutput <- mbPipe mb_stdout pfdStdOutput ReadMode hndStdError <- mbPipe mb_stderr pfdStdError ReadMode ph <- mkProcessHandle proc_handle return (hndStdInput, hndStdOutput, hndStdError, ph) {-# NOINLINE runInteractiveProcess_lock #-} runInteractiveProcess_lock :: MVar () runInteractiveProcess_lock = unsafePerformIO $ newMVar () foreign import ccall unsafe "runInteractiveProcess" c_runInteractiveProcess :: Ptr CString -> CString -> Ptr CString -> FD -> FD -> FD -> Ptr FD -> Ptr FD -> Ptr FD -> CInt -- non-zero: set child's SIGINT handler -> CLong -- SIGINT handler -> CInt -- non-zero: set child's SIGQUIT handler -> CLong -- SIGQUIT handler -> CInt -- flags -> IO PHANDLE #endif /* __GLASGOW_HASKELL__ */ ignoreSignal, defaultSignal :: CLong ignoreSignal = CONST_SIG_IGN defaultSignal = CONST_SIG_DFL #else #ifdef __GLASGOW_HASKELL__ runGenProcess_ fun CreateProcess{ cmdspec = cmdsp, cwd = mb_cwd, env = mb_env, std_in = mb_stdin, std_out = mb_stdout, std_err = mb_stderr, close_fds = mb_close_fds, create_group = mb_create_group } _ignored_mb_sigint _ignored_mb_sigquit = do (cmd, cmdline) <- commandToProcess cmdsp withFilePathException cmd $ alloca $ \ pfdStdInput -> alloca $ \ pfdStdOutput -> alloca $ \ pfdStdError -> maybeWith withCEnvironment mb_env $ \pEnv -> maybeWith withCWString mb_cwd $ \pWorkDir -> do withCWString cmdline $ \pcmdline -> do fdin <- mbFd fun fd_stdin mb_stdin fdout <- mbFd fun fd_stdout mb_stdout fderr <- mbFd fun fd_stderr mb_stderr -- #2650: we must ensure mutual exclusion of c_runInteractiveProcess, -- because otherwise there is a race condition whereby one thread -- has created some pipes, and another thread spawns a process which -- accidentally inherits some of the pipe handles that the first -- thread has created. -- -- An MVar in Haskell is the best way to do this, because there -- is no way to do one-time thread-safe initialisation of a mutex -- the C code. Also the MVar will be cheaper when not running -- the threaded RTS. proc_handle <- withMVar runInteractiveProcess_lock $ \_ -> throwErrnoIfBadPHandle fun $ c_runInteractiveProcess pcmdline pWorkDir pEnv fdin fdout fderr pfdStdInput pfdStdOutput pfdStdError ((if mb_close_fds then RUN_PROCESS_IN_CLOSE_FDS else 0) .|.(if mb_create_group then RUN_PROCESS_IN_NEW_GROUP else 0)) hndStdInput <- mbPipe mb_stdin pfdStdInput WriteMode hndStdOutput <- mbPipe mb_stdout pfdStdOutput ReadMode hndStdError <- mbPipe mb_stderr pfdStdError ReadMode ph <- mkProcessHandle proc_handle return (hndStdInput, hndStdOutput, hndStdError, ph) {-# NOINLINE runInteractiveProcess_lock #-} runInteractiveProcess_lock :: MVar () runInteractiveProcess_lock = unsafePerformIO $ newMVar () foreign import ccall unsafe "runInteractiveProcess" c_runInteractiveProcess :: CWString -> CWString -> Ptr CWString -> FD -> FD -> FD -> Ptr FD -> Ptr FD -> Ptr FD -> CInt -- flags -> IO PHANDLE #endif #endif /* __GLASGOW_HASKELL__ */ fd_stdin, fd_stdout, fd_stderr :: FD fd_stdin = 0 fd_stdout = 1 fd_stderr = 2 mbFd :: String -> FD -> StdStream -> IO FD mbFd _ _std CreatePipe = return (-1) mbFd _fun std Inherit = return std mbFd fun _std (UseHandle hdl) = #if __GLASGOW_HASKELL__ < 611 withHandle_ fun hdl $ return . haFD #else withHandle fun hdl $ \h@Handle__{haDevice=dev,..} -> case cast dev of Just fd -> do -- clear the O_NONBLOCK flag on this FD, if it is set, since -- we're exposing it externally (see #3316) fd <- FD.setNonBlockingMode fd False return (Handle__{haDevice=fd,..}, FD.fdFD fd) Nothing -> ioError (mkIOError illegalOperationErrorType "createProcess" (Just hdl) Nothing `ioeSetErrorString` "handle is not a file descriptor") #endif mbPipe :: StdStream -> Ptr FD -> IOMode -> IO (Maybe Handle) mbPipe CreatePipe pfd mode = fmap Just (pfdToHandle pfd mode) mbPipe _std _pfd _mode = return Nothing pfdToHandle :: Ptr FD -> IOMode -> IO Handle pfdToHandle pfd mode = do fd <- peek pfd let filepath = "fd:" ++ show fd #if __GLASGOW_HASKELL__ >= 611 (fD,fd_type) <- FD.mkFD (fromIntegral fd) mode (Just (Stream,0,0)) -- avoid calling fstat() False {-is_socket-} False {-non-blocking-} fD <- FD.setNonBlockingMode fD True -- see #3316 enc <- getLocaleEncoding mkHandleFromFD fD fd_type filepath mode False {-is_socket-} (Just enc) #else fdToHandle' fd (Just Stream) False {-Windows: not a socket, Unix: don't set non-blocking-} filepath mode True {-binary-} #endif #if __GLASGOW_HASKELL__ < 703 getLocaleEncoding :: IO TextEncoding getLocaleEncoding = return localeEncoding #endif #ifndef __HUGS__ -- ---------------------------------------------------------------------------- -- commandToProcess {- | Turns a shell command into a raw command. Usually this involves wrapping it in an invocation of the shell. There's a difference in the signature of commandToProcess between the Windows and Unix versions. On Unix, exec takes a list of strings, and we want to pass our command to /bin/sh as a single argument. On Windows, CreateProcess takes a single string for the command, which is later decomposed by cmd.exe. In this case, we just want to prepend @\"c:\WINDOWS\CMD.EXE \/c\"@ to our command line. The command-line translation that we normally do for arguments on Windows isn't required (or desirable) here. -} #if !defined(mingw32_HOST_OS) && !defined(__MINGW32__) commandToProcess :: CmdSpec -> (FilePath, [String]) commandToProcess (ShellCommand string) = ("/bin/sh", ["-c", string]) commandToProcess (RawCommand cmd args) = (cmd, args) #else commandToProcess :: CmdSpec -> IO (FilePath, String) commandToProcess (ShellCommand string) = do cmd <- findCommandInterpreter return (cmd, translate cmd ++ " /c " ++ string) -- We don't want to put the cmd into a single -- argument, because cmd.exe will not try to split it up. Instead, -- we just tack the command on the end of the cmd.exe command line, -- which partly works. There seem to be some quoting issues, but -- I don't have the energy to find+fix them right now (ToDo). --SDM -- (later) Now I don't know what the above comment means. sigh. commandToProcess (RawCommand cmd args) = do return (cmd, translate cmd ++ concatMap ((' ':) . translate) args) -- Find CMD.EXE (or COMMAND.COM on Win98). We use the same algorithm as -- system() in the VC++ CRT (Vc7/crt/src/system.c in a VC++ installation). findCommandInterpreter :: IO FilePath findCommandInterpreter = do -- try COMSPEC first #ifdef base3 catchJust (\e -> case e of IOException e | isDoesNotExistError e -> Just e _otherwise -> Nothing) #else catchJust (\e -> if isDoesNotExistError e then Just e else Nothing) #endif (getEnv "COMSPEC") $ \e -> do -- try to find CMD.EXE or COMMAND.COM {- XXX We used to look at _osver (using cbits) and pick which shell to use with let filename | osver .&. 0x8000 /= 0 = "command.com" | otherwise = "cmd.exe" We ought to use GetVersionEx instead, but for now we just look for either filename -} path <- getEnv "PATH" let -- use our own version of System.Directory.findExecutable, because -- that assumes the .exe suffix. search :: [FilePath] -> IO (Maybe FilePath) search [] = return Nothing search (d:ds) = do let path1 = d "cmd.exe" path2 = d "command.com" b1 <- doesFileExist path1 b2 <- doesFileExist path2 if b1 then return (Just path1) else if b2 then return (Just path2) else search ds -- mb_path <- search (splitSearchPath path) case mb_path of Nothing -> ioError (mkIOError doesNotExistErrorType "findCommandInterpreter" Nothing Nothing) Just cmd -> return cmd #endif #endif /* __HUGS__ */ -- ------------------------------------------------------------------------ -- Escaping commands for shells {- On Windows we also use this for running commands. We use CreateProcess, passing a single command-line string (lpCommandLine) as its argument. (CreateProcess is well documented on http://msdn.microsoft.com.) - It parses the beginning of the string to find the command. If the file name has embedded spaces, it must be quoted, using double quotes thus "foo\this that\cmd" arg1 arg2 - The invoked command can in turn access the entire lpCommandLine string, and the C runtime does indeed do so, parsing it to generate the traditional argument vector argv[0], argv[1], etc. It does this using a complex and arcane set of rules which are described here: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vccelng/htm/progs_12.asp (if this URL stops working, you might be able to find it by searching for "Parsing C Command-Line Arguments" on MSDN. Also, the code in the Microsoft C runtime that does this translation is shipped with VC++). Our goal in runProcess is to take a command filename and list of arguments, and construct a string which inverts the translatsions described above, such that the program at the other end sees exactly the same arguments in its argv[] that we passed to rawSystem. This inverse translation is implemented by 'translate' below. Here are some pages that give informations on Windows-related limitations and deviations from Unix conventions: http://support.microsoft.com/default.aspx?scid=kb;en-us;830473 Command lines and environment variables effectively limited to 8191 characters on Win XP, 2047 on NT/2000 (probably even less on Win 9x): http://www.microsoft.com/windowsxp/home/using/productdoc/en/default.asp?url=/WINDOWSXP/home/using/productdoc/en/percent.asp Command-line substitution under Windows XP. IIRC these facilities (or at least a large subset of them) are available on Win NT and 2000. Some might be available on Win 9x. http://www.microsoft.com/windowsxp/home/using/productdoc/en/default.asp?url=/WINDOWSXP/home/using/productdoc/en/Cmd.asp How CMD.EXE processes command lines. Note: CreateProcess does have a separate argument (lpApplicationName) with which you can specify the command, but we have to slap the command into lpCommandLine anyway, so that argv[0] is what a C program expects (namely the application name). So it seems simpler to just use lpCommandLine alone, which CreateProcess supports. -} translate :: String -> String #if mingw32_HOST_OS translate str = '"' : snd (foldr escape (True,"\"") str) where escape '"' (b, str) = (True, '\\' : '"' : str) escape '\\' (True, str) = (True, '\\' : '\\' : str) escape '\\' (False, str) = (False, '\\' : str) escape c (b, str) = (False, c : str) -- See long comment above for what this function is trying to do. -- -- The Bool passed back along the string is True iff the -- rest of the string is a sequence of backslashes followed by -- a double quote. #else translate str = '\'' : foldr escape "'" str where escape '\'' = showString "'\\''" escape c = showChar c #endif -- ---------------------------------------------------------------------------- -- Utils withFilePathException :: FilePath -> IO a -> IO a withFilePathException fpath act = handle mapEx act where #ifdef base4 mapEx ex = ioError (ioeSetFileName ex fpath) #else mapEx (IOException (IOError h iot fun str _)) = ioError (IOError h iot fun str (Just fpath)) #endif #if !defined(mingw32_HOST_OS) && !defined(__MINGW32__) withCEnvironment :: [(String,String)] -> (Ptr CString -> IO a) -> IO a withCEnvironment envir act = let env' = map (\(name, val) -> name ++ ('=':val)) envir in withMany withCString env' (\pEnv -> withArray0 nullPtr pEnv act) #else withCEnvironment :: [(String,String)] -> (Ptr CWString -> IO a) -> IO a withCEnvironment envir act = let env' = foldr (\(name, val) env -> name ++ ('=':val)++'\0':env) "\0" envir in withCWString env' (act . castPtr) #endif