import Data.Dynamic
import Data.Int ( Int64 )
import Data.IORef
+import Data.List
import Data.Typeable
import System.CPUTime
import System.IO
unqual <- io (GHC.getPrintUnqual session)
return $! showSDocForUser unqual doc
------------------------------------------------------------------------------
--- User code exception handling
+-- --------------------------------------------------------------------------
+-- Inferior Sessions Exceptions (used by the debugger)
--- This hierarchy of exceptions is used to signal interruption of a child session
-data BkptException = StopChildSession -- A child debugging session requests to be stopped
- | ChildSessionStopped String
+data InfSessionException =
+ StopChildSession -- A child session requests to be stopped
+ | StopParentSession -- A child session requests to be stopped
+ -- AND that the parent session quits after that
+ | ChildSessionStopped String -- A child session has stopped
deriving Typeable
--- This is the exception handler for exceptions generated by the
--- user's code and exceptions coming from children sessions;
--- it normally just prints out the exception. The
--- handler must be recursive, in case showing the exception causes
--- more exceptions to be raised.
---
--- Bugfix: if the user closed stdout or stderr, the flushing will fail,
--- raising another exception. We therefore don't put the recursive
--- handler arond the flushing operation, so if stderr is closed
--- GHCi will just die gracefully rather than going into an infinite loop.
-handler :: Exception -> GHCi Bool
-handler (DynException dyn)
- | Just StopChildSession <- fromDynamic dyn
- -- propagate to the parent session
- = ASSERTM (liftM not isTopLevel) >> throwDyn StopChildSession
-
- | Just (ChildSessionStopped msg) <- fromDynamic dyn
- -- Revert CAFs and display some message
- = ASSERTM (isTopLevel) >>
- io (revertCAFs >> putStrLn msg) >>
- return False
-
-handler exception = do
- flushInterpBuffers
- io installSignalHandlers
- ghciHandle handler (showException exception >> return False)
-
-showException (DynException dyn) =
- case fromDynamic dyn of
- Nothing -> io (putStrLn ("*** Exception: (unknown)"))
- Just Interrupted -> io (putStrLn "Interrupted.")
- Just (CmdLineError s) -> io (putStrLn s) -- omit the location for CmdLineError
- Just ph@PhaseFailed{} -> io (putStrLn (showGhcException ph "")) -- ditto
- Just other_ghc_ex -> io (print other_ghc_ex)
-
-showException other_exception
- = io (putStrLn ("*** Exception: " ++ show other_exception))
-
------------------------------------------------------------------------------
--- recursive exception handlers
-
--- Don't forget to unblock async exceptions in the handler, or if we're
--- in an exception loop (eg. let a = error a in a) the ^C exception
--- may never be delivered. Thanks to Marcin for pointing out the bug.
-
-ghciHandle :: (Exception -> GHCi a) -> GHCi a -> GHCi a
-ghciHandle h (GHCi m) = GHCi $ \s ->
- Exception.catch (m s)
- (\e -> unGHCi (ghciUnblock (h e)) s)
-
-ghciUnblock :: GHCi a -> GHCi a
-ghciUnblock (GHCi a) = GHCi $ \s -> Exception.unblock (a s)
------------------------------------------------------------------------------
+-- --------------------------------------------------------------------------
-- timing & statistics
timeIt :: GHCi a -> GHCi a
GLOBAL_VAR(flush_interp, error "no flush_interp", IO ())
GLOBAL_VAR(turn_off_buffering, error "no flush_stdout", IO ())
-no_buf_cmd = "System.IO.hSetBuffering System.IO.stdout System.IO.NoBuffering" ++
- " Prelude.>> System.IO.hSetBuffering System.IO.stderr System.IO.NoBuffering"
-flush_cmd = "System.IO.hFlush System.IO.stdout Prelude.>> System.IO.hFlush System.IO.stderr"
+command_sequence :: [String] -> String
+command_sequence = unwords . intersperse "Prelude.>>"
+
+no_buffer :: String -> String
+no_buffer h = unwords ["System.IO.hSetBuffering",
+ "System.IO." ++ h,
+ "System.IO.NoBuffering"]
+
+no_buf_cmd :: String
+no_buf_cmd = command_sequence $ map no_buffer ["stdout", "stderr", "stdin"]
+
+flush_buffer :: String -> String
+flush_buffer h = unwords ["System.IO.hFlush", "System.IO." ++ h]
+
+flush_cmd :: String
+flush_cmd = command_sequence [flush_buffer "stdout", flush_buffer "stderr"]
-initInterpBuffering :: Session -> IO ()
+initInterpBuffering :: GHC.Session -> IO ()
initInterpBuffering session
= do maybe_hval <- GHC.compileExpr session no_buf_cmd