InteractiveUI.hs 115 KB
Newer Older
1 2 3
{-# OPTIONS -fno-cse #-}
-- -fno-cse is needed for GLOBAL_VAR's to behave properly

4 5 6 7
-----------------------------------------------------------------------------
--
-- GHC Interactive User Interface
--
8
-- (c) The GHC Team 2005-2006
9 10
--
-----------------------------------------------------------------------------
11

12 13 14 15 16 17 18
module InteractiveUI (
        interactiveUI,
        GhciSettings(..),
        defaultGhciSettings,
        ghciCommands,
        ghciWelcomeMsg
    ) where
19

20 21
#include "HsVersions.h"

dterei's avatar
dterei committed
22 23 24
-- GHCi
import qualified GhciMonad ( args, runStmt )
import GhciMonad hiding ( args, runStmt )
25
import GhciTags
26
import Debugger
27

28
-- The GHC interface
dterei's avatar
dterei committed
29
import DynFlags
30
import GhcMonad ( modifySession )
dterei's avatar
dterei committed
31 32 33 34
import qualified GHC
import GHC ( LoadHowMuch(..), Target(..),  TargetId(..), InteractiveImport(..),
             TyThing(..), Phase, BreakIndex, Resume, SingleStep, Ghc,
             handleSourceError )
35
import HsImpExp
dterei's avatar
dterei committed
36
import HscTypes ( tyThingParent_maybe, handleFlagWarnings, getSafeMode, hsc_IC, 
37
                  setInteractivePrintName )
dterei's avatar
dterei committed
38
import Module
39
import Name
dterei's avatar
dterei committed
40 41 42
import Packages ( trusted, getPackageDetails, exposed, exposedModules, pkgIdMap )
import PprTyThing
import RdrName ( getGRE_NameQualifier_maybes )
43
import SrcLoc
dterei's avatar
dterei committed
44 45 46 47 48
import qualified Lexer

import StringBuffer
import UniqFM ( eltsUFM )
import Outputable hiding ( printForUser, printForUserPartWay, bold )
49 50

-- Other random utilities
dterei's avatar
dterei committed
51
import BasicTypes hiding ( isTopLevel )
52
import Config
dterei's avatar
dterei committed
53 54 55
import Digraph
import Encoding
import FastString
56
import Linker
dterei's avatar
dterei committed
57
import Maybes ( orElse, expectJust )
dterei's avatar
dterei committed
58 59
import NameSet
import Panic hiding ( showException )
60
import Util
sof's avatar
sof committed
61

dterei's avatar
dterei committed
62
-- Haskell Libraries
63
import System.Console.Haskeline as Haskeline
64

dterei's avatar
dterei committed
65 66
import Control.Applicative hiding (empty)
import Control.Monad as Monad
67 68
import Control.Monad.Trans.Class
import Control.Monad.IO.Class
69

dterei's avatar
dterei committed
70
import Data.Array
Simon Marlow's avatar
Simon Marlow committed
71
import qualified Data.ByteString.Char8 as BS
dterei's avatar
dterei committed
72
import Data.Char
Ian Lynagh's avatar
Ian Lynagh committed
73
import Data.Function
dterei's avatar
dterei committed
74 75 76
import Data.IORef ( IORef, readIORef, writeIORef )
import Data.List ( find, group, intercalate, intersperse, isPrefixOf, nub,
                   partition, sort, sortBy )
77
import Data.Maybe
dterei's avatar
dterei committed
78

79
import Exception hiding (catch)
dterei's avatar
dterei committed
80 81 82 83

import Foreign.C
import Foreign.Safe

84
import System.Cmd
dterei's avatar
dterei committed
85
import System.Directory
86
import System.Environment
dterei's avatar
dterei committed
87
import System.Exit ( exitWith, ExitCode(..) )
dterei's avatar
dterei committed
88
import System.FilePath
ross's avatar
ross committed
89
import System.IO
90
import System.IO.Error
dterei's avatar
dterei committed
91
import System.IO.Unsafe ( unsafePerformIO )
Simon Marlow's avatar
Simon Marlow committed
92
import Text.Printf
93

dterei's avatar
dterei committed
94 95 96 97 98 99 100
#ifndef mingw32_HOST_OS
import System.Posix hiding ( getEnv )
#else
import qualified System.Win32
#endif

import GHC.Exts ( unsafeCoerce# )
dterei's avatar
dterei committed
101 102
import GHC.IO.Exception ( IOErrorType(InvalidArgument) )
import GHC.IO.Handle ( hFlushAll )
dterei's avatar
dterei committed
103
import GHC.TopHandler ( topHandler )
104

105

106 107
-----------------------------------------------------------------------------

108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123
data GhciSettings = GhciSettings {
        availableCommands :: [Command],
        shortHelpText     :: String,
        fullHelpText      :: String,
        defPrompt         :: String
    }

defaultGhciSettings :: GhciSettings
defaultGhciSettings =
    GhciSettings {
        availableCommands = ghciCommands,
        shortHelpText     = defShortHelpText,
        fullHelpText      = defFullHelpText,
        defPrompt         = default_prompt
    }

124 125 126
ghciWelcomeMsg :: String
ghciWelcomeMsg = "GHCi, version " ++ cProjectVersion ++
                 ": http://www.haskell.org/ghc/  :? for help"
127

Simon Marlow's avatar
Simon Marlow committed
128
cmdName :: Command -> String
129
cmdName (n,_,_) = n
130

Simon Marlow's avatar
Simon Marlow committed
131
GLOBAL_VAR(macros_ref, [], [Command])
Simon Marlow's avatar
Simon Marlow committed
132

133 134
ghciCommands :: [Command]
ghciCommands = [
135 136 137 138 139 140 141 142 143 144 145 146
  -- Hugs users are accustomed to :e, so make sure it doesn't overlap
  ("?",         keepGoing help,                 noCompletion),
  ("add",       keepGoingPaths addModule,       completeFilename),
  ("abandon",   keepGoing abandonCmd,           noCompletion),
  ("break",     keepGoing breakCmd,             completeIdentifier),
  ("back",      keepGoing backCmd,              noCompletion),
  ("browse",    keepGoing' (browseCmd False),   completeModule),
  ("browse!",   keepGoing' (browseCmd True),    completeModule),
  ("cd",        keepGoing' changeDirectory,     completeFilename),
  ("check",     keepGoing' checkModule,         completeHomeModule),
  ("continue",  keepGoing continueCmd,          noCompletion),
  ("cmd",       keepGoing cmdCmd,               completeExpression),
147 148
  ("ctags",     keepGoing createCTagsWithLineNumbersCmd, completeFilename),
  ("ctags!",    keepGoing createCTagsWithRegExesCmd, completeFilename),
149 150 151
  ("def",       keepGoing (defineMacro False),  completeExpression),
  ("def!",      keepGoing (defineMacro True),   completeExpression),
  ("delete",    keepGoing deleteCmd,            noCompletion),
152
  ("edit",      keepGoing' editFile,            completeFilename),
153 154 155 156 157
  ("etags",     keepGoing createETagsFileCmd,   completeFilename),
  ("force",     keepGoing forceCmd,             completeExpression),
  ("forward",   keepGoing forwardCmd,           noCompletion),
  ("help",      keepGoing help,                 noCompletion),
  ("history",   keepGoing historyCmd,           noCompletion),
158 159
  ("info",      keepGoing' (info False),        completeIdentifier),
  ("info!",     keepGoing' (info True),         completeIdentifier),
160
  ("issafe",    keepGoing' isSafeCmd,           completeModule),
161 162
  ("kind",      keepGoing' (kindOfType False),  completeIdentifier),
  ("kind!",     keepGoing' (kindOfType True),   completeIdentifier),
163 164
  ("load",      keepGoingPaths loadModule_,     completeHomeModuleOrFile),
  ("list",      keepGoing' listCmd,             noCompletion),
165
  ("module",    keepGoing moduleCmd,            completeSetModule),
166 167 168 169 170
  ("main",      keepGoing runMain,              completeFilename),
  ("print",     keepGoing printCmd,             completeExpression),
  ("quit",      quit,                           noCompletion),
  ("reload",    keepGoing' reloadModule,        noCompletion),
  ("run",       keepGoing runRun,               completeFilename),
vivian's avatar
vivian committed
171
  ("script",    keepGoing' scriptCmd,           completeFilename),
172
  ("set",       keepGoing setCmd,               completeSetOptions),
173
  ("seti",      keepGoing setiCmd,              completeSeti),
174
  ("show",      keepGoing showCmd,              completeShowOptions),
175
  ("showi",     keepGoing showiCmd,             completeShowiOptions),
176 177 178 179 180 181 182 183
  ("sprint",    keepGoing sprintCmd,            completeExpression),
  ("step",      keepGoing stepCmd,              completeIdentifier),
  ("steplocal", keepGoing stepLocalCmd,         completeIdentifier),
  ("stepmodule",keepGoing stepModuleCmd,        completeIdentifier),
  ("type",      keepGoing' typeOfExpr,          completeExpression),
  ("trace",     keepGoing traceCmd,             completeExpression),
  ("undef",     keepGoing undefineMacro,        completeMacro),
  ("unset",     keepGoing unsetOptions,         completeSetOptions)
184 185
  ]

186

dterei's avatar
dterei committed
187
-- We initialize readline (in the interactiveUI function) to use
188 189 190 191
-- word_break_chars as the default set of completion word break characters.
-- This can be overridden for a particular command (for example, filename
-- expansion shouldn't consider '/' to be a word break) by setting the third
-- entry in the Command tuple above.
dterei's avatar
dterei committed
192
--
193 194
-- NOTE: in order for us to override the default correctly, any custom entry
-- must be a SUBSET of word_break_chars.
195
word_break_chars :: String
196 197 198 199
word_break_chars = let symbols = "!#$%&*+/<=>?@\\^|-~"
                       specials = "(),;[]`{}"
                       spaces = " \t\n"
                   in spaces ++ specials ++ symbols
200

201
flagWordBreakChars :: String
202 203 204
flagWordBreakChars = " \t\n"


205 206 207 208 209
keepGoing :: (String -> GHCi ()) -> (String -> InputT GHCi Bool)
keepGoing a str = keepGoing' (lift . a) str

keepGoing' :: Monad m => (String -> m ()) -> String -> m Bool
keepGoing' a str = a str >> return False
210

211
keepGoingPaths :: ([FilePath] -> InputT GHCi ()) -> (String -> InputT GHCi Bool)
Ian Lynagh's avatar
Ian Lynagh committed
212 213
keepGoingPaths a str
 = do case toArgs str of
Ian Lynagh's avatar
Ian Lynagh committed
214
          Left err -> liftIO $ hPutStrLn stderr err
Ian Lynagh's avatar
Ian Lynagh committed
215 216
          Right args -> a args
      return False
sof's avatar
sof committed
217

218 219
defShortHelpText :: String
defShortHelpText = "use :? for help.\n"
220

221 222
defFullHelpText :: String
defFullHelpText =
dterei's avatar
dterei committed
223 224 225 226 227 228 229 230 231 232 233 234
  " Commands available from the prompt:\n" ++
  "\n" ++
  "   <statement>                 evaluate/run <statement>\n" ++
  "   :                           repeat last command\n" ++
  "   :{\\n ..lines.. \\n:}\\n       multiline command\n" ++
  "   :add [*]<module> ...        add module(s) to the current target set\n" ++
  "   :browse[!] [[*]<mod>]       display the names defined by module <mod>\n" ++
  "                               (!: more details; *: all top-level names)\n" ++
  "   :cd <dir>                   change directory to <dir>\n" ++
  "   :cmd <expr>                 run the commands returned by <expr>::IO String\n" ++
  "   :ctags[!] [<file>]          create tags file for Vi (default: \"tags\")\n" ++
  "                               (!: use regex instead of line number)\n" ++
235 236
  "   :def <cmd> <expr>           define command :<cmd> (later defined command has\n" ++
  "                               precedence, ::<cmd> is always a builtin command)\n" ++
dterei's avatar
dterei committed
237 238 239 240
  "   :edit <file>                edit file\n" ++
  "   :edit                       edit last module\n" ++
  "   :etags [<file>]             create tags file for Emacs (default: \"TAGS\")\n" ++
  "   :help, :?                   display this list of commands\n" ++
241 242
  "   :info[!] [<name> ...]       display information about the given names\n" ++
  "                               (!: do not filter instances)\n" ++
dterei's avatar
dterei committed
243 244 245 246 247 248 249 250
  "   :issafe [<mod>]             display safe haskell information of module <mod>\n" ++
  "   :kind <type>                show the kind of <type>\n" ++
  "   :load [*]<module> ...       load module(s) and their dependents\n" ++
  "   :main [<arguments> ...]     run the main function with the given arguments\n" ++
  "   :module [+/-] [*]<mod> ...  set the context for expression evaluation\n" ++
  "   :quit                       exit GHCi\n" ++
  "   :reload                     reload the current module set\n" ++
  "   :run function [<arguments> ...] run the function with the given arguments\n" ++
251
  "   :script <filename>          run the script <filename>\n" ++
dterei's avatar
dterei committed
252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278
  "   :type <expr>                show the type of <expr>\n" ++
  "   :undef <cmd>                undefine user-defined command :<cmd>\n" ++
  "   :!<command>                 run the shell command <command>\n" ++
  "\n" ++
  " -- Commands for debugging:\n" ++
  "\n" ++
  "   :abandon                    at a breakpoint, abandon current computation\n" ++
  "   :back                       go back in the history (after :trace)\n" ++
  "   :break [<mod>] <l> [<col>]  set a breakpoint at the specified location\n" ++
  "   :break <name>               set a breakpoint on the specified function\n" ++
  "   :continue                   resume after a breakpoint\n" ++
  "   :delete <number>            delete the specified breakpoint\n" ++
  "   :delete *                   delete all breakpoints\n" ++
  "   :force <expr>               print <expr>, forcing unevaluated parts\n" ++
  "   :forward                    go forward in the history (after :back)\n" ++
  "   :history [<n>]              after :trace, show the execution history\n" ++
  "   :list                       show the source code around current breakpoint\n" ++
  "   :list identifier            show the source code for <identifier>\n" ++
  "   :list [<module>] <line>     show the source code around line number <line>\n" ++
  "   :print [<name> ...]         prints a value without forcing its computation\n" ++
  "   :sprint [<name> ...]        simplifed version of :print\n" ++
  "   :step                       single-step after stopping at a breakpoint\n"++
  "   :step <expr>                single-step into <expr>\n"++
  "   :steplocal                  single-step within the current top-level binding\n"++
  "   :stepmodule                 single-step restricted to the current module\n"++
  "   :trace                      trace after stopping at a breakpoint\n"++
  "   :trace <expr>               evaluate <expr> with tracing on (see :history)\n"++
dterei's avatar
dterei committed
279

dterei's avatar
dterei committed
280 281 282 283
  "\n" ++
  " -- Commands for changing settings:\n" ++
  "\n" ++
  "   :set <option> ...           set options\n" ++
284
  "   :seti <option> ...          set options for interactive evaluation only\n" ++
dterei's avatar
dterei committed
285 286 287 288 289 290 291 292 293
  "   :set args <arg> ...         set the arguments returned by System.getArgs\n" ++
  "   :set prog <progname>        set the value returned by System.getProgName\n" ++
  "   :set prompt <prompt>        set the prompt used in GHCi\n" ++
  "   :set editor <cmd>           set the command used for :edit\n" ++
  "   :set stop [<n>] <cmd>       set the command to run when a breakpoint is hit\n" ++
  "   :unset <option> ...         unset options\n" ++
  "\n" ++
  "  Options for ':set' and ':unset':\n" ++
  "\n" ++
dterei's avatar
dterei committed
294
  "    +m            allow multiline commands\n" ++
dterei's avatar
dterei committed
295 296 297 298 299 300 301 302 303 304 305 306 307
  "    +r            revert top-level expressions after each evaluation\n" ++
  "    +s            print timing/memory stats after each evaluation\n" ++
  "    +t            print type after evaluation\n" ++
  "    -<flags>      most GHC command line flags can also be set here\n" ++
  "                         (eg. -v2, -fglasgow-exts, etc.)\n" ++
  "                    for GHCi-specific flags, see User's Guide,\n"++
  "                    Flag reference, Interactive-mode options\n" ++
  "\n" ++
  " -- Commands for displaying information:\n" ++
  "\n" ++
  "   :show bindings              show the current bindings made at the prompt\n" ++
  "   :show breaks                show the active breakpoints\n" ++
  "   :show context               show the breakpoint context\n" ++
308
  "   :show imports               show the current imports\n" ++
dterei's avatar
dterei committed
309 310
  "   :show modules               show the currently loaded modules\n" ++
  "   :show packages              show the currently active package flags\n" ++
311
  "   :show language              show the currently active language flags\n" ++
dterei's avatar
dterei committed
312 313
  "   :show <setting>             show value of <setting>, which is one of\n" ++
  "                                  [args, prog, prompt, editor, stop]\n" ++
314
  "   :showi language             show language flags for interactive evaluation\n" ++
dterei's avatar
dterei committed
315
  "\n"
316

Simon Marlow's avatar
Simon Marlow committed
317
findEditor :: IO String
Simon Marlow's avatar
Simon Marlow committed
318
findEditor = do
dterei's avatar
dterei committed
319
  getEnv "EDITOR"
320
    `catchIO` \_ -> do
321
#if mingw32_HOST_OS
Ian Lynagh's avatar
Ian Lynagh committed
322 323
        win <- System.Win32.getWindowsDirectory
        return (win </> "notepad.exe")
Simon Marlow's avatar
Simon Marlow committed
324
#else
Ian Lynagh's avatar
Ian Lynagh committed
325
        return ""
Simon Marlow's avatar
Simon Marlow committed
326 327
#endif

Simon Marlow's avatar
Simon Marlow committed
328 329
foreign import ccall unsafe "rts_isProfiled" isProfiled :: IO CInt

Simon Marlow's avatar
Simon Marlow committed
330
default_progname, default_prompt, default_stop :: String
Boris Lykah's avatar
Boris Lykah committed
331 332 333 334
default_progname = "<interactive>"
default_prompt = "%s> "
default_stop = ""

Simon Marlow's avatar
Simon Marlow committed
335 336 337
default_args :: [String]
default_args = []

338
interactiveUI :: GhciSettings -> [(FilePath, Maybe Phase)] -> Maybe [String]
339
              -> Ghc ()
340
interactiveUI config srcs maybe_exprs = do
341 342 343
   -- although GHCi compiles with -prof, it is not usable: the byte-code
   -- compiler and interpreter don't work with profiling.  So we check for
   -- this up front and emit a helpful error message (#2197)
Simon Marlow's avatar
Simon Marlow committed
344
   i <- liftIO $ isProfiled
dterei's avatar
dterei committed
345
   when (i /= 0) $
346
     throwGhcException (InstallationError "GHCi cannot be used when compiled with -prof")
347

348 349 350 351 352 353 354 355
   -- HACK! If we happen to get into an infinite loop (eg the user
   -- types 'let x=x in x' at the prompt), then the thread will block
   -- on a blackhole, and become unreachable during GC.  The GC will
   -- detect that it is unreachable and send it the NonTermination
   -- exception.  However, since the thread is unreachable, everything
   -- it refers to might be finalized, including the standard Handles.
   -- This sounds like a bug, but we don't have a good solution right
   -- now.
356 357 358
   _ <- liftIO $ newStablePtr stdin
   _ <- liftIO $ newStablePtr stdout
   _ <- liftIO $ newStablePtr stderr
359

Ian Lynagh's avatar
Ian Lynagh committed
360
    -- Initialise buffering for the *interpreted* I/O system
361
   initInterpBuffering
362

363
   -- The initial set of DynFlags used for interactive evaluation is the same
364 365
   -- as the global DynFlags, plus -XExtendedDefaultRules and
   -- -XNoMonomorphismRestriction.
366
   dflags <- getDynFlags
367 368 369 370
   let dflags' = (`xopt_set` Opt_ExtendedDefaultRules)
               . (`xopt_unset` Opt_MonomorphismRestriction)
               $ dflags
   GHC.setInteractiveDynFlags dflags'
371

372
   liftIO $ when (isNothing maybe_exprs) $ do
Ian Lynagh's avatar
Ian Lynagh committed
373 374 375 376 377 378 379 380 381 382
        -- Only for GHCi (not runghc and ghc -e):

        -- Turn buffering off for the compiled program's stdout/stderr
        turnOffBuffering
        -- Turn buffering off for GHCi's stdout
        hFlush stdout
        hSetBuffering stdout NoBuffering
        -- We don't want the cmd line to buffer any input that might be
        -- intended for the program, so unbuffer stdin.
        hSetBuffering stdin NoBuffering
383
#if defined(mingw32_HOST_OS)
384 385 386 387 388
        -- On Unix, stdin will use the locale encoding.  The IO library
        -- doesn't do this on Windows (yet), so for now we use UTF-8,
        -- for consistency with GHC 6.10 and to make the tests work.
        hSetEncoding stdin utf8
#endif
Ian Lynagh's avatar
Ian Lynagh committed
389

390
   default_editor <- liftIO $ findEditor
Simon Marlow's avatar
Simon Marlow committed
391

Ian Lynagh's avatar
Ian Lynagh committed
392
   startGHCi (runGHCi srcs maybe_exprs)
dterei's avatar
dterei committed
393 394
        GHCiState{ progname       = default_progname,
                   GhciMonad.args = default_args,
395 396
                   prompt         = defPrompt config,
                   def_prompt     = defPrompt config,
dterei's avatar
dterei committed
397 398 399 400 401 402 403
                   stop           = default_stop,
                   editor         = default_editor,
                   options        = [],
                   line_number    = 1,
                   break_ctr      = 0,
                   breaks         = [],
                   tickarrays     = emptyModuleEnv,
404
                   ghci_commands  = availableCommands config,
dterei's avatar
dterei committed
405 406
                   last_command   = Nothing,
                   cmdqueue       = [],
mnislaih's avatar
mnislaih committed
407
                   remembered_ctx = [],
dterei's avatar
dterei committed
408
                   transient_ctx  = [],
409 410 411
                   ghc_e          = isJust maybe_exprs,
                   short_help     = shortHelpText config,
                   long_help      = fullHelpText config
mnislaih's avatar
mnislaih committed
412
                 }
rrt's avatar
rrt committed
413

414 415
   return ()

416 417
withGhcAppData :: (FilePath -> IO a) -> IO a -> IO a
withGhcAppData right left = do
418
    either_dir <- tryIO (getAppUserDataDirectory "ghc")
419 420 421 422 423
    case either_dir of
        Right dir ->
            do createDirectoryIfMissing False dir `catchIO` \_ -> return ()
               right dir
        _ -> left
424

Ian Lynagh's avatar
Ian Lynagh committed
425 426
runGHCi :: [(FilePath, Maybe Phase)] -> Maybe [String] -> GHCi ()
runGHCi paths maybe_exprs = do
427
  dflags <- getDynFlags
428
  let
ian@well-typed.com's avatar
ian@well-typed.com committed
429
   read_dot_files = not (gopt Opt_IgnoreDotGhci dflags)
430

431 432
   current_dir = return (Just ".ghci")

Ian Lynagh's avatar
Ian Lynagh committed
433
   app_user_dir = liftIO $ withGhcAppData
434 435
                    (\dir -> return (Just (dir </> "ghci.conf")))
                    (return Nothing)
436 437

   home_dir = do
438
    either_dir <- liftIO $ tryIO (getEnv "HOME")
439 440 441 442
    case either_dir of
      Right home -> return (Just (home </> ".ghci"))
      _ -> return Nothing

443 444 445 446
   canonicalizePath' :: FilePath -> IO (Maybe FilePath)
   canonicalizePath' fp = liftM Just (canonicalizePath fp)
                `catchIO` \_ -> return Nothing

447 448
   sourceConfigFile :: FilePath -> GHCi ()
   sourceConfigFile file = do
Ian Lynagh's avatar
Ian Lynagh committed
449
     exists <- liftIO $ doesFileExist file
450
     when exists $ do
Ian Lynagh's avatar
Ian Lynagh committed
451 452
       dir_ok  <- liftIO $ checkPerms (getDirectory file)
       file_ok <- liftIO $ checkPerms file
453
       when (dir_ok && file_ok) $ do
454
         either_hdl <- liftIO $ tryIO (openFile file ReadMode)
455 456
         case either_hdl of
           Left _e   -> return ()
457 458 459
           -- NOTE: this assumes that runInputT won't affect the terminal;
           -- can we assume this will always be the case?
           -- This would be a good place for runFileInputT.
460 461
           Right hdl ->
               do runInputTWithPrefs defaultPrefs defaultSettings $
462
                            runCommands $ fileLoop hdl
463
                  liftIO (hClose hdl `catchIO` \_ -> return ())
464 465
     where
      getDirectory f = case takeDirectory f of "" -> "."; d -> d
466 467
  --

468
  setGHCContextFromGHCiState
Ian Lynagh's avatar
Ian Lynagh committed
469

470
  when (read_dot_files) $ do
471
    mcfgs0 <- sequence $ [ current_dir, app_user_dir, home_dir ] ++ map (return . Just ) (ghciScripts dflags)
Ian Lynagh's avatar
Ian Lynagh committed
472
    mcfgs <- liftIO $ mapM canonicalizePath' (catMaybes mcfgs0)
473
    mapM_ sourceConfigFile $ nub $ catMaybes mcfgs
474 475
        -- nub, because we don't want to read .ghci twice if the
        -- CWD is $HOME.
476

477
  -- Perform a :load for files given on the GHCi command line
478 479 480
  -- When in -e mode, if the load fails then we want to stop
  -- immediately rather than going on to evaluate the expression.
  when (not (null paths)) $ do
Ian Lynagh's avatar
Ian Lynagh committed
481
     ok <- ghciHandle (\e -> do showException e; return Failed) $
482
                -- TODO: this is a hack.
483 484
                runInputTWithPrefs defaultPrefs defaultSettings $
                    loadModule paths
Ian Lynagh's avatar
Ian Lynagh committed
485
     when (isJust maybe_exprs && failed ok) $
Ian Lynagh's avatar
Ian Lynagh committed
486
        liftIO (exitWith (ExitFailure 1))
487

488 489
  installInteractivePrint (interactivePrint dflags) (isJust maybe_exprs)

490 491
  -- if verbosity is greater than 0, or we are connected to a
  -- terminal, display the prompt in the interactive loop.
Ian Lynagh's avatar
Ian Lynagh committed
492
  is_tty <- liftIO (hIsTerminalDevice stdin)
493 494
  let show_prompt = verbosity dflags > 0 || is_tty

495 496 497
  -- reset line number
  getGHCiState >>= \st -> setGHCiState st{line_number=1}

Ian Lynagh's avatar
Ian Lynagh committed
498
  case maybe_exprs of
Ian Lynagh's avatar
Ian Lynagh committed
499
        Nothing ->
sof's avatar
sof committed
500
          do
Ian Lynagh's avatar
Ian Lynagh committed
501
            -- enter the interactive loop
502
            runGHCiInput $ runCommands $ nextInputLine show_prompt is_tty
Ian Lynagh's avatar
Ian Lynagh committed
503
        Just exprs -> do
Ian Lynagh's avatar
Ian Lynagh committed
504
            -- just evaluate the expression we were given
Ian Lynagh's avatar
Ian Lynagh committed
505
            enqueueCommands exprs
dterei's avatar
dterei committed
506 507 508 509 510 511 512 513
            let hdle e = do st <- getGHCiState
                            -- flush the interpreter's stdout/stderr on exit (#3890)
                            flushInterpBuffers
                            -- Jump through some hoops to get the
                            -- current progname in the exception text:
                            -- <progname>: <exception>
                            liftIO $ withProgName (progname st)
                                   $ topHandler e
514
                                   -- this used to be topHandlerFastExit, see #2228
515
            runInputTWithPrefs defaultPrefs defaultSettings $ do
dterei's avatar
dterei committed
516
                runCommands' hdle (return Nothing)
517 518

  -- and finally, exit
Ian Lynagh's avatar
Ian Lynagh committed
519
  liftIO $ when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
520

521 522
runGHCiInput :: InputT GHCi a -> GHCi a
runGHCiInput f = do
Ian Lynagh's avatar
Ian Lynagh committed
523
    dflags <- getDynFlags
ian@well-typed.com's avatar
ian@well-typed.com committed
524
    histFile <- if gopt Opt_GhciHistory dflags
Ian Lynagh's avatar
Ian Lynagh committed
525 526 527
                then liftIO $ withGhcAppData (\dir -> return (Just (dir </> "ghci_history")))
                                             (return Nothing)
                else return Nothing
dterei's avatar
dterei committed
528 529 530
    runInputT
        (setComplete ghciCompleteWord $ defaultSettings {historyFile = histFile})
        f
531

532
-- | How to get the next input line from the user
533 534 535
nextInputLine :: Bool -> Bool -> InputT GHCi (Maybe String)
nextInputLine show_prompt is_tty
  | is_tty = do
dterei's avatar
dterei committed
536 537
    prmpt <- if show_prompt then lift mkPrompt else return ""
    r <- getInputLine prmpt
538 539
    incrementLineNo
    return r
540 541 542
  | otherwise = do
    when show_prompt $ lift mkPrompt >>= liftIO . putStr
    fileLoop stdin
543

544
-- NOTE: We only read .ghci files if they are owned by the current user,
dterei's avatar
dterei committed
545
-- and aren't world writable.  Otherwise, we could be accidentally
546 547
-- running code planted by a malicious third party.

rrt's avatar
rrt committed
548 549 550 551
-- Furthermore, We only read ./.ghci if . is owned by the current user
-- and isn't writable by anyone else.  I think this is sufficient: we
-- don't need to check .. and ../.. etc. because "."  always refers to
-- the same directory while a process is running.
552 553

checkPerms :: String -> IO Bool
554
#ifdef mingw32_HOST_OS
dterei's avatar
dterei committed
555
checkPerms _ = return True
sof's avatar
sof committed
556
#else
Simon Marlow's avatar
Simon Marlow committed
557
checkPerms name =
558
  handleIO (\_ -> return False) $ do
dterei's avatar
dterei committed
559 560 561 562 563 564 565 566
    st <- getFileStatus name
    me <- getRealUserID
    if fileOwner st /= me then do
        putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
        return False
     else do
        let mode = System.Posix.fileMode st
        if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
dterei's avatar
dterei committed
567
            || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
dterei's avatar
dterei committed
568
            then do
dterei's avatar
dterei committed
569
                putStrLn $ "*** WARNING: " ++ name ++
dterei's avatar
dterei committed
570 571 572
                           " is writable by someone else, IGNORING!"
                return False
            else return True
sof's avatar
sof committed
573
#endif
574

575 576
incrementLineNo :: InputT GHCi ()
incrementLineNo = do
vivian's avatar
vivian committed
577 578 579 580 581
   st <- lift $ getGHCiState
   let ln = 1+(line_number st)
   lift $ setGHCiState st{line_number=ln}

fileLoop :: Handle -> InputT GHCi (Maybe String)
582
fileLoop hdl = do
583
   l <- liftIO $ tryIO $ hGetLine hdl
584
   case l of
585 586
        Left e | isEOFError e              -> return Nothing
               | InvalidArgument <- etype  -> return Nothing
587
               | otherwise                 -> liftIO $ ioError e
588 589 590 591 592
                where etype = ioeGetErrorType e
                -- treat InvalidArgument in the same way as EOF:
                -- this can happen if the user closed stdin, or
                -- perhaps did getContents which closes stdin at
                -- EOF.
dterei's avatar
dterei committed
593
        Right l' -> do
594
           incrementLineNo
dterei's avatar
dterei committed
595
           return (Just l')
596

Simon Marlow's avatar
Simon Marlow committed
597
mkPrompt :: GHCi String
598
mkPrompt = do
599
  imports <- GHC.getContext
600
  resumes <- GHC.getResumeContext
601 602 603 604

  context_bit <-
        case resumes of
            [] -> return empty
Simon Marlow's avatar
Simon Marlow committed
605
            r:_ -> do
606 607 608 609 610
                let ix = GHC.resumeHistoryIx r
                if ix == 0
                   then return (brackets (ppr (GHC.resumeSpan r)) <> space)
                   else do
                        let hist = GHC.resumeHistory r !! (ix-1)
dterei's avatar
dterei committed
611 612 613
                        pan <- GHC.getHistorySpan hist
                        return (brackets (ppr (negate ix) <> char ':'
                                          <+> ppr pan) <> space)
614
  let
Simon Marlow's avatar
Simon Marlow committed
615
        dots | _:rs <- resumes, not (null rs) = text "... "
616 617
             | otherwise = empty

618 619
        rev_imports = reverse imports -- rightmost are the most recent
        modules_bit =
620
             hsep [ char '*' <> ppr m | IIModule m <- rev_imports ] <+>
621 622 623 624 625
             hsep (map ppr [ myIdeclName d | IIDecl d <- rev_imports ])

         --  use the 'as' name if there is one
        myIdeclName d | Just m <- ideclAs d = m
                      | otherwise           = unLoc (ideclName d)
626

627 628 629 630 631 632
        deflt_prompt = dots <> context_bit <> modules_bit

        f ('%':'s':xs) = deflt_prompt <> f xs
        f ('%':'%':xs) = char '%' <> f xs
        f (x:xs) = char x <> f xs
        f [] = empty
dterei's avatar
dterei committed
633

634
  st <- getGHCiState
Ian Lynagh's avatar
Ian Lynagh committed
635 636
  dflags <- getDynFlags
  return (showSDoc dflags (f (prompt st)))
637

638

639 640 641 642 643 644 645 646
queryQueue :: GHCi (Maybe String)
queryQueue = do
  st <- getGHCiState
  case cmdqueue st of
    []   -> return Nothing
    c:cs -> do setGHCiState st{ cmdqueue = cs }
               return (Just c)

647 648 649 650 651 652
-- Reconfigurable pretty-printing Ticket #5461
installInteractivePrint :: Maybe String -> Bool -> GHCi ()
installInteractivePrint Nothing _  = return ()
installInteractivePrint (Just ipFun) exprmode = do
  ok <- trySuccess $ do
                (name:_) <- GHC.parseName ipFun
653 654
                modifySession (\he -> let new_ic = setInteractivePrintName (hsc_IC he) name 
                                      in he{hsc_IC = new_ic})
655 656 657 658
                return Succeeded

  when (failed ok && exprmode) $ liftIO (exitWith (ExitFailure 1))

659
-- | The main read-eval-print loop
660
runCommands :: InputT GHCi (Maybe String) -> InputT GHCi ()
661 662
runCommands = runCommands' handler

dterei's avatar
dterei committed
663
runCommands' :: (SomeException -> GHCi Bool) -- ^ Exception handler
664
             -> InputT GHCi (Maybe String) -> InputT GHCi ()
dterei's avatar
dterei committed
665
runCommands' eh gCmd = do
666
    b <- ghandle (\e -> case fromException e of
vivian's avatar
vivian committed
667
                          Just UserInterrupt -> return $ Just False
668
                          _ -> case fromException e of
dterei's avatar
dterei committed
669 670
                                 Just ghce ->
                                   do liftIO (print (ghce :: GhcException))
vivian's avatar
vivian committed
671
                                      return Nothing
672 673
                                 _other ->
                                   liftIO (Exception.throwIO e))
dterei's avatar
dterei committed
674
            (runOneCommand eh gCmd)
vivian's avatar
vivian committed
675 676
    case b of
      Nothing -> return ()
dterei's avatar
dterei committed
677
      Just _  -> runCommands' eh gCmd
678

679
-- | Evaluate a single line of user input (either :<command> or Haskell code)
680
runOneCommand :: (SomeException -> GHCi Bool) -> InputT GHCi (Maybe String)
vivian's avatar
vivian committed
681
            -> InputT GHCi (Maybe Bool)
dterei's avatar
dterei committed
682
runOneCommand eh gCmd = do
683 684
  -- run a previously queued command if there is one, otherwise get new
  -- input from user
dterei's avatar
dterei committed
685 686 687
  mb_cmd0 <- noSpace (lift queryQueue)
  mb_cmd1 <- maybe (noSpace gCmd) (return . Just) mb_cmd0
  case mb_cmd1 of
vivian's avatar
vivian committed
688 689
    Nothing -> return Nothing
    Just c  -> ghciHandle (\e -> lift $ eh e >>= return . Just) $
690 691
             handleSourceError printErrorAndKeepGoing
               (doCommand c)
vivian's avatar
vivian committed
692 693
               -- source error's are handled by runStmt
               -- is the handler necessary here?
694
  where
695
    printErrorAndKeepGoing err = do
696
        GHC.printException err
vivian's avatar
vivian committed
697
        return $ Just True
698

699
    noSpace q = q >>= maybe (return Nothing)
dterei's avatar
dterei committed
700 701 702
                            (\c -> case removeSpaces c of
                                     ""   -> noSpace q
                                     ":{" -> multiLineCmd q
703
                                     c'   -> return (Just c') )
704
    multiLineCmd q = do
705
      st <- lift getGHCiState
706
      let p = prompt st
707
      lift $ setGHCiState st{ prompt = "%s| " }
708
      mb_cmd <- collectCommand q ""
dterei's avatar
dterei committed
709
      lift $ getGHCiState >>= \st' -> setGHCiState st'{ prompt = p }
710
      return mb_cmd
dterei's avatar
dterei committed
711
    -- we can't use removeSpaces for the sublines here, so
712
    -- multiline commands are somewhat more brittle against
dterei's avatar
dterei committed
713 714
    -- fileformat errors (such as \r in dos input on unix),
    -- we get rid of any extra spaces for the ":}" test;
715
    -- we also avoid silent failure if ":}" is not found;
dterei's avatar
dterei committed
716
    -- and since there is no (?) valid occurrence of \r (as
717 718
    -- opposed to its String representation, "\r") inside a
    -- ghci command, we replace any such with ' ' (argh:-(
dterei's avatar
dterei committed
719
    collectCommand q c = q >>=
720
      maybe (liftIO (ioError collectError))
dterei's avatar
dterei committed
721 722
            (\l->if removeSpaces l == ":}"
                 then return (Just $ removeSpaces c)
723
                 else collectCommand q (c ++ "\n" ++ map normSpace l))
724
      where normSpace '\r' = ' '
dterei's avatar
dterei committed
725
            normSpace   x  = x
dterei's avatar
dterei committed
726
    -- SDM (2007-11-07): is userError the one to use here?
727
    collectError = userError "unterminated multiline command :{ .. :}"
728 729 730 731 732

    -- | Handle a line of input
    doCommand :: String -> InputT GHCi (Maybe Bool)

    -- command
vivian's avatar
vivian committed
733 734 735 736 737
    doCommand (':' : cmd) = do
      result <- specialCommand cmd
      case result of
        True -> return Nothing
        _    -> return $ Just True
738 739 740

    -- haskell
    doCommand stmt = do
vivian's avatar
vivian committed
741 742
      ml <- lift $ isOptionSet Multiline
      if ml
dterei's avatar
dterei committed
743 744
        then do
          mb_stmt <- checkInputForLayout stmt gCmd
vivian's avatar
vivian committed
745 746 747 748 749 750 751 752 753 754 755
          case mb_stmt of
            Nothing      -> return $ Just True
            Just ml_stmt -> do
              result <- timeIt $ lift $ runStmt ml_stmt GHC.RunToCompletion
              return $ Just result
        else do
          result <- timeIt $ lift $ runStmt stmt GHC.RunToCompletion
          return $ Just result

-- #4316
-- lex the input.  If there is an unclosed layout context, request input
vivian's avatar
vivian committed
756
checkInputForLayout :: String -> InputT GHCi (Maybe String)
vivian's avatar
vivian committed
757
                    -> InputT GHCi (Maybe String)
vivian's avatar
vivian committed
758
checkInputForLayout stmt getStmt = do
vivian's avatar
vivian committed
759 760
   dflags' <- lift $ getDynFlags
   let dflags = xopt_set dflags' Opt_AlternativeLayoutRule
dterei's avatar
dterei committed
761 762 763 764
   st0 <- lift $ getGHCiState
   let buf'   =  stringToStringBuffer stmt
       loc    = mkRealSrcLoc (fsLit (progname st0)) (line_number st0) 1
       pstate = Lexer.mkPState dflags buf' loc
vivian's avatar
vivian committed
765 766 767
   case Lexer.unP goToEnd pstate of
     (Lexer.POk _ False) -> return $ Just stmt
     _other              -> do
dterei's avatar
dterei committed
768 769 770
       st1 <- lift getGHCiState
       let p = prompt st1
       lift $ setGHCiState st1{ prompt = "%s| " }
vivian's avatar
vivian committed
771 772 773
       mb_stmt <- ghciHandle (\ex -> case fromException ex of
                            Just UserInterrupt -> return Nothing
                            _ -> case fromException ex of
dterei's avatar
dterei committed
774 775
                                 Just ghce ->
                                   do liftIO (print (ghce :: GhcException))
vivian's avatar
vivian committed
776
                                      return Nothing
dterei's avatar
dterei committed
777
                                 _other -> liftIO (Exception.throwIO ex))
vivian's avatar
vivian committed
778
                     getStmt
dterei's avatar
dterei committed
779
       lift $ getGHCiState >>= \st' -> setGHCiState st'{ prompt = p }
vivian's avatar
vivian committed
780 781 782 783 784 785
       -- the recursive call does not recycle parser state
       -- as we use a new string buffer
       case mb_stmt of
         Nothing  -> return Nothing
         Just str -> if str == ""
           then return $ Just stmt
vivian's avatar
vivian committed
786 787
           else do
             checkInputForLayout (stmt++"\n"++str) getStmt
vivian's avatar
vivian committed
788 789
     where goToEnd = do
             eof <- Lexer.nextIsEOF
dterei's avatar
dterei committed
790
             if eof
vivian's avatar
vivian committed
791 792
               then Lexer.activeContext
               else Lexer.lexer return >> goToEnd
793 794 795 796 797 798

enqueueCommands :: [String] -> GHCi ()
enqueueCommands cmds = do
  st <- getGHCiState
  setGHCiState st{ cmdqueue = cmds ++ cmdqueue st }

799 800 801
-- | If we one of these strings prefixes a command, then we treat it as a decl
-- rather than a stmt.
declPrefixes :: [String]
802
declPrefixes = ["class ","data ","newtype ","type ","instance ", "deriving ",
parcs's avatar
parcs committed
803
                "foreign ", "default ", "default("]
804

805
-- | Entry point to execute some haskell code from user
806 807
runStmt :: String -> SingleStep -> GHCi Bool
runStmt stmt step
808
 -- empty
809 810
 | null (filter (not.isSpace) stmt)
 = return False