X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Futils%2FPanic.lhs;h=6251d1baf414bc81b0ca6bc8af5f478b10a1de88;hb=153b9cb9b11e05c4edb1b6bc0a7b972660e41f70;hp=81818df42e2a8b87a3484b0e643177414adddd35;hpb=1dbd9ba1fa6518393572997a547d6a9156f533c6;p=ghc-hetmet.git

diff --git a/ghc/compiler/utils/Panic.lhs b/ghc/compiler/utils/Panic.lhs
index 81818df..6251d1b 100644
--- a/ghc/compiler/utils/Panic.lhs
+++ b/ghc/compiler/utils/Panic.lhs
@@ -12,32 +12,74 @@ some unnecessary loops in the module dependency graph.
 module Panic  
    ( 
      GhcException(..), ghcError, progName, 
-     panic, panic#, assertPanic, trace 
+     pgmError,
+     panic, panic#, assertPanic, trace,
+     showException, showGhcException, tryMost,
+     installSignalHandlers, 
+
+     catchJust, tryJust, ioErrors, throwTo,
    ) where
 
+#include "HsVersions.h"
+
 import Config
 import FastTypes
 
-import Dynamic
-import IOExts
-import Exception
+#ifndef mingw32_HOST_OS
+# if __GLASGOW_HASKELL__ > 504
+import System.Posix.Signals
+# else
+import Posix		( Handler(Catch), installHandler, sigINT, sigQUIT )
+# endif /* GHC > 504 */
+#endif /* mingw32_HOST_OS */
+
+#if defined(mingw32_HOST_OS) && __GLASGOW_HASKELL__ >= 603
+import GHC.ConsoleHandler
+#endif
+
+# if __GLASGOW_HASKELL__ < 500
+import EXCEPTION        ( raiseInThread )
+# else
+import EXCEPTION	( throwTo )
+# endif /* GHC < 500 */
+
+#if __GLASGOW_HASKELL__ > 408
+import EXCEPTION	( catchJust, tryJust, ioErrors )
+#endif
+
+import CONCURRENT	( myThreadId )
+import DYNAMIC
+import qualified EXCEPTION as Exception
+import TRACE		( trace )
+import UNSAFE_IO	( unsafePerformIO )
 
 import System
-#include "HsVersions.h"
 \end{code}
 
 GHC's own exception type.
 
 \begin{code}
 ghcError :: GhcException -> a
-ghcError e = throwDyn e
+ghcError e = Exception.throwDyn e
+
+-- error messages all take the form
+--
+--	<location>: <error>
+--
+-- If the location is on the command line, or in GHC itself, then 
+-- <location>="ghc".  All of the error types below correspond to 
+-- a <location> of "ghc", except for ProgramError (where the string is
+-- assumed to contain a location already, so we don't print one).
 
 data GhcException
-  = PhaseFailed String ExitCode
-  | Interrupted
+  = PhaseFailed String		-- name of phase 
+  		ExitCode	-- an external phase (eg. cpp) failed
+  | Interrupted			-- someone pressed ^C
   | UsageError String		-- prints the short usage msg after the error
+  | CmdLineError String		-- cmdline prob, but doesn't print usage
   | Panic String		-- the `impossible' happened
-  | OtherError String		-- just prints the error message
+  | InstallationError String	-- an installation problem
+  | ProgramError String		-- error in the user's code, probably
   deriving Eq
 
 progName = unsafePerformIO (getProgName)
@@ -45,35 +87,61 @@ progName = unsafePerformIO (getProgName)
 
 short_usage = "Usage: For basic information, try the `--help' option."
    
+showException :: Exception.Exception -> String
+-- Show expected dynamic exceptions specially
+showException (Exception.DynException d) | Just e <- fromDynamic d 
+					 = show (e::GhcException)
+showException other_exn	       	 	 = show other_exn
+
 instance Show GhcException where
-  showsPrec _ e = showString progName . showString ": " . showBarf e
+  showsPrec _ e@(ProgramError _) = showGhcException e
+  showsPrec _ e = showString progName . showString ": " . showGhcException e
 
-showBarf (UsageError str)
+showGhcException (UsageError str)
    = showString str . showChar '\n' . showString short_usage
-showBarf (OtherError str)
+showGhcException (PhaseFailed phase code)
+   = showString "phase `" . showString phase . 
+     showString "' failed (exitcode = " . shows int_code . 
+     showString ")"
+  where
+    int_code = 
+      case code of
+        ExitSuccess   -> (0::Int)
+	ExitFailure x -> x
+showGhcException (CmdLineError str)
+   = showString str
+showGhcException (ProgramError str)
    = showString str
-showBarf (PhaseFailed phase code)
-   = showString phase . showString " failed, code = " . shows code
-showBarf (Interrupted)
+showGhcException (InstallationError str)
+   = showString str
+showGhcException (Interrupted)
    = showString "interrupted"
-showBarf (Panic s)
+showGhcException (Panic s)
    = showString ("panic! (the `impossible' happened, GHC version "
 		 ++ cProjectVersion ++ "):\n\t"
 	         ++ s ++ "\n\n"
 	         ++ "Please report it as a compiler bug "
-	         ++ "to glasgow-haskell-bugs@haskell.org.\n\n")
+	         ++ "to glasgow-haskell-bugs@haskell.org,\n"
+		 ++ "or http://sourceforge.net/projects/ghc/.\n\n")
+
+#if __GLASGOW_HASKELL__ < 603
+myMkTyConApp = mkAppTy
+#else 
+myMkTyConApp = mkTyConApp
+#endif
 
 ghcExceptionTc = mkTyCon "GhcException"
 {-# NOINLINE ghcExceptionTc #-}
 instance Typeable GhcException where
-  typeOf _ = mkAppTy ghcExceptionTc []
+  typeOf _ = myMkTyConApp ghcExceptionTc []
 \end{code}
 
 Panics and asserts.
 
 \begin{code}
-panic :: String -> a
-panic x = throwDyn (Panic x)
+panic, pgmError :: String -> a
+panic    x = Exception.throwDyn (Panic x)
+pgmError x = Exception.throwDyn (ProgramError x)
 
 -- #-versions because panic can't return an unboxed int, and that's
 -- what TAG_ is with GHC at the moment.  Ugh. (Simon)
@@ -84,6 +152,74 @@ panic# s = case (panic s) of () -> _ILIT 0
 
 assertPanic :: String -> Int -> a
 assertPanic file line = 
-  throw (AssertionFailed 
+  Exception.throw (Exception.AssertionFailed 
            ("ASSERT failed! file " ++ file ++ ", line " ++ show line))
 \end{code}
+
+\begin{code}
+-- | tryMost is like try, but passes through Interrupted and Panic
+-- exceptions.  Used when we want soft failures when reading interface
+-- files, for example.
+
+tryMost :: IO a -> IO (Either Exception.Exception a)
+tryMost action = do r <- myTry action; filter r
+  where
+   filter (Left e@(Exception.DynException d))
+	    | Just ghc_ex <- fromDynamic d
+		= case ghc_ex of
+		    Interrupted -> Exception.throw e
+		    Panic _     -> Exception.throw e
+		    _other      -> return (Left e)
+   filter other 
+     = return other
+
+#if __GLASGOW_HASKELL__ <= 408
+myTry = Exception.tryAllIO
+#else
+myTry = Exception.try
+#endif
+\end{code}	
+
+Compatibility stuff:
+
+\begin{code}
+#if __GLASGOW_HASKELL__ <= 408
+catchJust = Exception.catchIO
+tryJust   = Exception.tryIO
+ioErrors  = Exception.justIoErrors
+throwTo   = Exception.raiseInThread
+#endif
+\end{code}
+
+Standard signal handlers for catching ^C, which just throw an
+exception in the main thread.  NOTE: must be called from the main
+thread.
+
+\begin{code}
+installSignalHandlers :: IO ()
+installSignalHandlers = do
+  main_thread <- myThreadId
+  let
+      interrupt_exn = Exception.DynException (toDyn Interrupted)
+      interrupt = throwTo main_thread interrupt_exn
+  --
+#if !defined(mingw32_HOST_OS)
+  installHandler sigQUIT (Catch interrupt) Nothing 
+  installHandler sigINT  (Catch interrupt) Nothing
+  return ()
+#elif __GLASGOW_HASKELL__ >= 603
+  -- GHC 6.3+ has support for console events on Windows
+  -- NOTE: running GHCi under a bash shell for some reason requires
+  -- you to press Ctrl-Break rather than Ctrl-C to provoke
+  -- an interrupt.  Ctrl-C is getting blocked somewhere, I don't know
+  -- why --SDM 17/12/2004
+  let sig_handler ControlC = interrupt
+      sig_handler Break    = interrupt
+      sig_handler _        = return ()
+
+  installHandler (Catch sig_handler)
+  return ()
+#else
+  return () -- nothing
+#endif
+\end{code}