1 files changed, 54 insertions, 1 deletions
diff --git a/System/Posix/Process/Internals.hs b/System/Posix/Process/Internals.hs
index 8639819..deb1992 100644
--- a/System/Posix/Process/Internals.hs
+++ b/System/Posix/Process/Internals.hs
@@ -1,8 +1,20 @@
 
-module System.Posix.Process.Internals (pPrPr_disableITimers, c_execvpe) where
+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)
+
+-- we had to move this into GHC.Conc in GHC to avoid recursive dependencies.
+-- it can be moved back when the signal handling stuff in base is moved out.
+data ProcessStatus = Exited ExitCode
+                   | Terminated Signal
+                   | Stopped Signal
+		   deriving (Eq, Ord, Show)
 
 -- this function disables the itimer, which would otherwise cause confusing
 -- signals to be sent to the new process.
@@ -11,3 +23,44 @@ foreign import ccall unsafe "pPrPr_disableITimers"
 
 foreign import ccall unsafe "execvpe"
   c_execvpe :: CString -> Ptr CString -> Ptr CString -> IO CInt
+
+decipherWaitStatus :: CInt -> IO ProcessStatus
+decipherWaitStatus wstat =
+  if c_WIFEXITED wstat /= 0
+      then do
+        let exitstatus = c_WEXITSTATUS wstat
+        if exitstatus == 0
+	   then return (Exited ExitSuccess)
+	   else return (Exited (ExitFailure (fromIntegral exitstatus)))
+      else do
+        if c_WIFSIGNALED wstat /= 0
+	   then do
+		let termsig = c_WTERMSIG wstat
+		return (Terminated (fromIntegral termsig))
+	   else do
+		if c_WIFSTOPPED wstat /= 0
+		   then do
+			let stopsig = c_WSTOPSIG wstat
+			return (Stopped (fromIntegral stopsig))
+		   else do
+			ioError (mkIOError illegalOperationErrorType
+				   "waitStatus" Nothing Nothing)
+
+foreign import ccall unsafe "__hsunix_wifexited"
+  c_WIFEXITED :: CInt -> CInt 
+
+foreign import ccall unsafe "__hsunix_wexitstatus"
+  c_WEXITSTATUS :: CInt -> CInt
+
+foreign import ccall unsafe "__hsunix_wifsignaled"
+  c_WIFSIGNALED :: CInt -> CInt
+
+foreign import ccall unsafe "__hsunix_wtermsig"
+  c_WTERMSIG :: CInt -> CInt 
+
+foreign import ccall unsafe "__hsunix_wifstopped"
+  c_WIFSTOPPED :: CInt -> CInt
+
+foreign import ccall unsafe "__hsunix_wstopsig"
+  c_WSTOPSIG :: CInt -> CInt
+