1 {-# OPTIONS_GHC -fno-cse -fno-warn-orphans #-}
2 -- -fno-cse is needed for GLOBAL_VAR's to behave properly
4 -----------------------------------------------------------------------------
6 -- Monadery code used in InteractiveUI
8 -- (c) The GHC Team 2005-2006
10 -----------------------------------------------------------------------------
12 module GhciMonad where
14 #include "HsVersions.h"
17 import GhcMonad hiding (liftIO)
18 import Outputable hiding (printForUser, printForUserPartWay)
19 import qualified Outputable
20 import Panic hiding (showException)
29 import qualified MonadUtils
34 import Data.Int ( Int64 )
37 import System.Environment
39 import Control.Monad as Monad
42 import System.Console.Haskeline (CompletionFunc, InputT)
43 import qualified System.Console.Haskeline as Haskeline
44 import Control.Monad.Trans as Trans
46 -----------------------------------------------------------------------------
49 type Command = (String, String -> InputT GHCi Bool, CompletionFunc GHCi)
51 data GHCiState = GHCiState
58 options :: [GHCiOption],
59 prelude :: GHC.Module,
61 breaks :: ![(Int, BreakLocation)],
62 tickarrays :: ModuleEnv TickArray,
63 -- tickarrays caches the TickArray for loaded modules,
64 -- so that we don't rebuild it each time the user sets
66 -- ":" at the GHCi prompt repeats the last command, so we
68 last_command :: Maybe Command,
70 remembered_ctx :: [CtxtCmd],
71 -- we remember the :module commands between :loads, so that
72 -- on a :reload we can replay them. See bugs #2049,
73 -- \#1873, #1360. Previously we tried to remember modules that
74 -- were supposed to be in the context but currently had errors,
75 -- but this was complicated. Just replaying the :module commands
76 -- seems to be the right thing.
77 ghc_e :: Bool -- True if this is 'ghc -e' (or runghc)
81 = SetContext [String] [String]
82 | AddModules [String] [String]
83 | RemModules [String] [String]
86 type TickArray = Array Int [(BreakIndex,SrcSpan)]
89 = ShowTiming -- show time/allocs after evaluation
90 | ShowType -- show the type of expressions
91 | RevertCAFs -- revert CAFs after every evaluation
96 { breakModule :: !GHC.Module
97 , breakLoc :: !SrcSpan
98 , breakTick :: {-# UNPACK #-} !Int
99 , onBreakCmd :: String
102 instance Eq BreakLocation where
103 loc1 == loc2 = breakModule loc1 == breakModule loc2 &&
104 breakTick loc1 == breakTick loc2
106 prettyLocations :: [(Int, BreakLocation)] -> SDoc
107 prettyLocations [] = text "No active breakpoints."
108 prettyLocations locs = vcat $ map (\(i, loc) -> brackets (int i) <+> ppr loc) $ reverse $ locs
110 instance Outputable BreakLocation where
111 ppr loc = (ppr $ breakModule loc) <+> ppr (breakLoc loc) <+>
112 if null (onBreakCmd loc)
114 else doubleQuotes (text (onBreakCmd loc))
116 recordBreak :: BreakLocation -> GHCi (Bool{- was already present -}, Int)
117 recordBreak brkLoc = do
119 let oldActiveBreaks = breaks st
120 -- don't store the same break point twice
121 case [ nm | (nm, loc) <- oldActiveBreaks, loc == brkLoc ] of
122 (nm:_) -> return (True, nm)
124 let oldCounter = break_ctr st
125 newCounter = oldCounter + 1
126 setGHCiState $ st { break_ctr = newCounter,
127 breaks = (oldCounter, brkLoc) : oldActiveBreaks
129 return (False, oldCounter)
131 newtype GHCi a = GHCi { unGHCi :: IORef GHCiState -> Ghc a }
133 reflectGHCi :: (Session, IORef GHCiState) -> GHCi a -> IO a
134 reflectGHCi (s, gs) m = unGhc (unGHCi m gs) s
136 reifyGHCi :: ((Session, IORef GHCiState) -> IO a) -> GHCi a
137 reifyGHCi f = GHCi f'
139 -- f' :: IORef GHCiState -> Ghc a
140 f' gs = reifyGhc (f'' gs)
141 -- f'' :: IORef GHCiState -> Session -> IO a
144 startGHCi :: GHCi a -> GHCiState -> Ghc a
145 startGHCi g state = do ref <- liftIO $ newIORef state; unGHCi g ref
147 instance Monad GHCi where
148 (GHCi m) >>= k = GHCi $ \s -> m s >>= \a -> unGHCi (k a) s
149 return a = GHCi $ \_ -> return a
151 instance Functor GHCi where
152 fmap f m = m >>= return . f
154 ghciHandleGhcException :: (GhcException -> GHCi a) -> GHCi a -> GHCi a
155 ghciHandleGhcException = handleGhcException
157 getGHCiState :: GHCi GHCiState
158 getGHCiState = GHCi $ \r -> liftIO $ readIORef r
159 setGHCiState :: GHCiState -> GHCi ()
160 setGHCiState s = GHCi $ \r -> liftIO $ writeIORef r s
162 liftGhc :: Ghc a -> GHCi a
163 liftGhc m = GHCi $ \_ -> m
165 instance MonadUtils.MonadIO GHCi where
166 liftIO = liftGhc . MonadUtils.liftIO
168 instance Trans.MonadIO Ghc where
169 liftIO = MonadUtils.liftIO
171 instance GhcMonad GHCi where
172 setSession s' = liftGhc $ setSession s'
173 getSession = liftGhc $ getSession
175 instance GhcMonad (InputT GHCi) where
176 setSession = lift . setSession
177 getSession = lift getSession
179 instance MonadUtils.MonadIO (InputT GHCi) where
180 liftIO = Trans.liftIO
182 instance ExceptionMonad GHCi where
183 gcatch m h = GHCi $ \r -> unGHCi m r `gcatch` (\e -> unGHCi (h e) r)
184 gblock (GHCi m) = GHCi $ \r -> gblock (m r)
185 gunblock (GHCi m) = GHCi $ \r -> gunblock (m r)
187 GHCi $ \s -> gmask $ \io_restore ->
189 g_restore (GHCi m) = GHCi $ \s' -> io_restore (m s')
191 unGHCi (f g_restore) s
193 instance MonadIO GHCi where
194 liftIO = MonadUtils.liftIO
196 instance Haskeline.MonadException GHCi where
200 -- XXX when Haskeline's MonadException changes, we can drop our
201 -- deprecated block/unblock methods
203 instance ExceptionMonad (InputT GHCi) where
204 gcatch = Haskeline.catch
205 gmask f = Haskeline.block (f Haskeline.unblock) -- slightly wrong
206 gblock = Haskeline.block
207 gunblock = Haskeline.unblock
209 -- for convenience...
210 getPrelude :: GHCi Module
211 getPrelude = getGHCiState >>= return . prelude
213 getDynFlags :: GhcMonad m => m DynFlags
215 GHC.getSessionDynFlags
217 setDynFlags :: DynFlags -> GHCi [PackageId]
218 setDynFlags dflags = do
219 GHC.setSessionDynFlags dflags
221 isOptionSet :: GHCiOption -> GHCi Bool
223 = do st <- getGHCiState
224 return (opt `elem` options st)
226 setOption :: GHCiOption -> GHCi ()
228 = do st <- getGHCiState
229 setGHCiState (st{ options = opt : filter (/= opt) (options st) })
231 unsetOption :: GHCiOption -> GHCi ()
233 = do st <- getGHCiState
234 setGHCiState (st{ options = filter (/= opt) (options st) })
236 printForUser :: GhcMonad m => SDoc -> m ()
237 printForUser doc = do
238 unqual <- GHC.getPrintUnqual
239 MonadUtils.liftIO $ Outputable.printForUser stdout unqual doc
241 printForUserPartWay :: SDoc -> GHCi ()
242 printForUserPartWay doc = do
243 unqual <- GHC.getPrintUnqual
244 liftIO $ Outputable.printForUserPartWay stdout opt_PprUserLength unqual doc
246 runStmt :: String -> GHC.SingleStep -> GHCi GHC.RunResult
247 runStmt expr step = do
250 withProgName (progname st) $
253 GHC.handleSourceError (\e -> do GHC.printException e
254 return GHC.RunFailed) $ do
255 GHC.runStmt expr step
257 resume :: (SrcSpan -> Bool) -> GHC.SingleStep -> GHCi GHC.RunResult
258 resume canLogSpan step = do
261 withProgName (progname st) $
264 GHC.resume canLogSpan step
266 -- --------------------------------------------------------------------------
267 -- timing & statistics
269 timeIt :: InputT GHCi a -> InputT GHCi a
271 = do b <- lift $ isOptionSet ShowTiming
274 else do allocs1 <- liftIO $ getAllocations
275 time1 <- liftIO $ getCPUTime
277 allocs2 <- liftIO $ getAllocations
278 time2 <- liftIO $ getCPUTime
279 liftIO $ printTimes (fromIntegral (allocs2 - allocs1))
283 foreign import ccall unsafe "getAllocations" getAllocations :: IO Int64
284 -- defined in ghc/rts/Stats.c
286 printTimes :: Integer -> Integer -> IO ()
287 printTimes allocs psecs
288 = do let secs = (fromIntegral psecs / (10^(12::Integer))) :: Float
289 secs_str = showFFloat (Just 2) secs
291 parens (text (secs_str "") <+> text "secs" <> comma <+>
292 text (show allocs) <+> text "bytes")))
294 -----------------------------------------------------------------------------
297 revertCAFs :: GHCi ()
299 liftIO rts_revertCAFs
301 when (not (ghc_e s)) $ liftIO turnOffBuffering
302 -- Have to turn off buffering again, because we just
303 -- reverted stdout, stderr & stdin to their defaults.
305 foreign import ccall "revertCAFs" rts_revertCAFs :: IO ()
306 -- Make it "safe", just in case
308 -----------------------------------------------------------------------------
309 -- To flush buffers for the *interpreted* computation we need
310 -- to refer to *its* stdout/stderr handles
312 GLOBAL_VAR(stdin_ptr, error "no stdin_ptr", Ptr ())
313 GLOBAL_VAR(stdout_ptr, error "no stdout_ptr", Ptr ())
314 GLOBAL_VAR(stderr_ptr, error "no stderr_ptr", Ptr ())
316 -- After various attempts, I believe this is the least bad way to do
317 -- what we want. We know look up the address of the static stdin,
318 -- stdout, and stderr closures in the loaded base package, and each
319 -- time we need to refer to them we cast the pointer to a Handle.
320 -- This avoids any problems with the CAF having been reverted, because
321 -- we'll always get the current value.
323 -- The previous attempt that didn't work was to compile an expression
324 -- like "hSetBuffering stdout NoBuffering" into an expression of type
325 -- IO () and run this expression each time we needed it, but the
326 -- problem is that evaluating the expression might cache the contents
327 -- of the Handle rather than referring to it from its static address
328 -- each time. There's no safe workaround for this.
330 initInterpBuffering :: Ghc ()
331 initInterpBuffering = do -- make sure these are linked
332 dflags <- GHC.getSessionDynFlags
336 -- ToDo: we should really look up these names properly, but
337 -- it's a fiddle and not all the bits are exposed via the GHC
339 mb_stdin_ptr <- ObjLink.lookupSymbol "base_GHCziIOziHandleziFD_stdin_closure"
340 mb_stdout_ptr <- ObjLink.lookupSymbol "base_GHCziIOziHandleziFD_stdout_closure"
341 mb_stderr_ptr <- ObjLink.lookupSymbol "base_GHCziIOziHandleziFD_stderr_closure"
343 let f ref (Just ptr) = writeIORef ref ptr
344 f _ Nothing = panic "interactiveUI:setBuffering2"
345 zipWithM_ f [stdin_ptr,stdout_ptr,stderr_ptr]
346 [mb_stdin_ptr,mb_stdout_ptr,mb_stderr_ptr]
348 flushInterpBuffers :: GHCi ()
350 = liftIO $ do getHandle stdout_ptr >>= hFlush
351 getHandle stderr_ptr >>= hFlush
353 turnOffBuffering :: IO ()
355 = do hdls <- mapM getHandle [stdin_ptr,stdout_ptr,stderr_ptr]
356 mapM_ (\h -> hSetBuffering h NoBuffering) hdls
358 getHandle :: IORef (Ptr ()) -> IO Handle
360 (Ptr addr) <- readIORef ref
361 case addrToHValue# addr of (# hval #) -> return (unsafeCoerce# hval)