UI.hs 137 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE CPP #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE MagicHash #-}
{-# LANGUAGE MultiWayIf #-}
{-# LANGUAGE NondecreasingIndentation #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE TupleSections #-}
{-# LANGUAGE ViewPatterns #-}

12
13
14
{-# OPTIONS -fno-cse #-}
-- -fno-cse is needed for GLOBAL_VAR's to behave properly

15
16
17
18
-----------------------------------------------------------------------------
--
-- GHC Interactive User Interface
--
19
-- (c) The GHC Team 2005-2006
20
21
--
-----------------------------------------------------------------------------
22

23
module GHCi.UI (
24
25
26
27
28
29
        interactiveUI,
        GhciSettings(..),
        defaultGhciSettings,
        ghciCommands,
        ghciWelcomeMsg
    ) where
30

31
32
#include "HsVersions.h"

dterei's avatar
dterei committed
33
-- GHCi
34
35
36
37
import qualified GHCi.UI.Monad as GhciMonad ( args, runStmt, runDecls )
import GHCi.UI.Monad hiding ( args, runStmt, runDecls )
import GHCi.UI.Tags
import GHCi.UI.Info
38
import Debugger
39

40
-- The GHC interface
41
import GHCi
42
43
import GHCi.RemoteTypes
import GHCi.BreakArray
dterei's avatar
dterei committed
44
import DynFlags
45
import ErrUtils
46
import GhcMonad ( modifySession )
dterei's avatar
dterei committed
47
48
49
import qualified GHC
import GHC ( LoadHowMuch(..), Target(..),  TargetId(..), InteractiveImport(..),
             TyThing(..), Phase, BreakIndex, Resume, SingleStep, Ghc,
50
             getModuleGraph, handleSourceError )
51
import HsImpExp
52
import HsSyn
53
import HscTypes ( tyThingParent_maybe, handleFlagWarnings, getSafeMode, hsc_IC,
54
                  setInteractivePrintName, hsc_dflags )
dterei's avatar
dterei committed
55
import Module
56
import Name
57
import Packages ( trusted, getPackageDetails, listVisibleModuleNames, pprFlag )
dterei's avatar
dterei committed
58
import PprTyThing
59
60
import PrelNames
import RdrName ( RdrName, getGRE_NameQualifier_maybes, getRdrName )
61
import SrcLoc
dterei's avatar
dterei committed
62
63
64
65
import qualified Lexer

import StringBuffer
import Outputable hiding ( printForUser, printForUserPartWay, bold )
66
67

-- Other random utilities
dterei's avatar
dterei committed
68
import BasicTypes hiding ( isTopLevel )
69
import Config
dterei's avatar
dterei committed
70
71
72
import Digraph
import Encoding
import FastString
73
import Linker
dterei's avatar
dterei committed
74
import Maybes ( orElse, expectJust )
dterei's avatar
dterei committed
75
76
import NameSet
import Panic hiding ( showException )
77
import Util
78
import qualified GHC.LanguageExtensions as LangExt
sof's avatar
sof committed
79

dterei's avatar
dterei committed
80
-- Haskell Libraries
81
import System.Console.Haskeline as Haskeline
82

dterei's avatar
dterei committed
83
import Control.Applicative hiding (empty)
84
85
import Control.DeepSeq (deepseq)
import Control.Monad as Monad
86
import Control.Monad.IO.Class
87
import Control.Monad.Trans.Class
88
import Control.Monad.Trans.Except
89

dterei's avatar
dterei committed
90
import Data.Array
Simon Marlow's avatar
Simon Marlow committed
91
import qualified Data.ByteString.Char8 as BS
dterei's avatar
dterei committed
92
import Data.Char
Ian Lynagh's avatar
Ian Lynagh committed
93
import Data.Function
94
import Data.IORef ( IORef, modifyIORef, newIORef, readIORef, writeIORef )
dterei's avatar
dterei committed
95
96
import Data.List ( find, group, intercalate, intersperse, isPrefixOf, nub,
                   partition, sort, sortBy )
97
import Data.Maybe
98
import qualified Data.Map as M
dterei's avatar
dterei committed
99

100
import Exception hiding (catch)
101
import Foreign
102
import GHC.Stack hiding (SrcLoc(..))
dterei's avatar
dterei committed
103
104

import System.Directory
105
import System.Environment
dterei's avatar
dterei committed
106
import System.Exit ( exitWith, ExitCode(..) )
dterei's avatar
dterei committed
107
import System.FilePath
ross's avatar
ross committed
108
import System.IO
109
import System.IO.Error
dterei's avatar
dterei committed
110
import System.IO.Unsafe ( unsafePerformIO )
111
import System.Process
Simon Marlow's avatar
Simon Marlow committed
112
import Text.Printf
113
import Text.Read ( readMaybe )
114

dterei's avatar
dterei committed
115
116
117
118
119
120
#ifndef mingw32_HOST_OS
import System.Posix hiding ( getEnv )
#else
import qualified System.Win32
#endif

dterei's avatar
dterei committed
121
122
import GHC.IO.Exception ( IOErrorType(InvalidArgument) )
import GHC.IO.Handle ( hFlushAll )
dterei's avatar
dterei committed
123
import GHC.TopHandler ( topHandler )
124

125
126
-----------------------------------------------------------------------------

127
128
129
data GhciSettings = GhciSettings {
        availableCommands :: [Command],
        shortHelpText     :: String,
130
131
132
        fullHelpText      :: String,
        defPrompt         :: String,
        defPrompt2        :: String
133
134
135
136
137
138
139
    }

defaultGhciSettings :: GhciSettings
defaultGhciSettings =
    GhciSettings {
        availableCommands = ghciCommands,
        shortHelpText     = defShortHelpText,
140
141
        defPrompt         = default_prompt,
        defPrompt2        = default_prompt2,
142
        fullHelpText      = defFullHelpText
143
144
    }

145
146
147
ghciWelcomeMsg :: String
ghciWelcomeMsg = "GHCi, version " ++ cProjectVersion ++
                 ": http://www.haskell.org/ghc/  :? for help"
148

Simon Marlow's avatar
Simon Marlow committed
149
GLOBAL_VAR(macros_ref, [], [Command])
Simon Marlow's avatar
Simon Marlow committed
150

151
ghciCommands :: [Command]
152
ghciCommands = map mkCmd [
153
154
155
156
157
158
159
160
161
162
163
164
  -- 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),
165
166
  ("ctags",     keepGoing createCTagsWithLineNumbersCmd, completeFilename),
  ("ctags!",    keepGoing createCTagsWithRegExesCmd, completeFilename),
167
168
169
  ("def",       keepGoing (defineMacro False),  completeExpression),
  ("def!",      keepGoing (defineMacro True),   completeExpression),
  ("delete",    keepGoing deleteCmd,            noCompletion),
170
  ("edit",      keepGoing' editFile,            completeFilename),
171
172
173
174
175
  ("etags",     keepGoing createETagsFileCmd,   completeFilename),
  ("force",     keepGoing forceCmd,             completeExpression),
  ("forward",   keepGoing forwardCmd,           noCompletion),
  ("help",      keepGoing help,                 noCompletion),
  ("history",   keepGoing historyCmd,           noCompletion),
176
177
  ("info",      keepGoing' (info False),        completeIdentifier),
  ("info!",     keepGoing' (info True),         completeIdentifier),
178
  ("issafe",    keepGoing' isSafeCmd,           completeModule),
179
180
  ("kind",      keepGoing' (kindOfType False),  completeIdentifier),
  ("kind!",     keepGoing' (kindOfType True),   completeIdentifier),
181
182
  ("load",      keepGoingPaths (loadModule_ False), completeHomeModuleOrFile),
  ("load!",     keepGoingPaths (loadModule_ True), completeHomeModuleOrFile),
183
  ("list",      keepGoing' listCmd,             noCompletion),
184
  ("module",    keepGoing moduleCmd,            completeSetModule),
185
186
187
  ("main",      keepGoing runMain,              completeFilename),
  ("print",     keepGoing printCmd,             completeExpression),
  ("quit",      quit,                           noCompletion),
188
189
  ("reload",    keepGoing' (reloadModule False), noCompletion),
  ("reload!",   keepGoing' (reloadModule True), noCompletion),
190
  ("run",       keepGoing runRun,               completeFilename),
vivian's avatar
vivian committed
191
  ("script",    keepGoing' scriptCmd,           completeFilename),
192
  ("set",       keepGoing setCmd,               completeSetOptions),
193
  ("seti",      keepGoing setiCmd,              completeSeti),
194
  ("show",      keepGoing showCmd,              completeShowOptions),
195
  ("showi",     keepGoing showiCmd,             completeShowiOptions),
196
197
198
199
200
201
202
  ("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),
203
204
  ("unset",     keepGoing unsetOptions,         completeSetOptions),
  ("where",     keepGoing whereCmd,             noCompletion)
205
  ] ++ map mkCmdHidden [ -- hidden commands
206
207
208
209
210
  ("all-types", keepGoing' allTypesCmd),
  ("complete",  keepGoing completeCmd),
  ("loc-at",    keepGoing' locAtCmd),
  ("type-at",   keepGoing' typeAtCmd),
  ("uses",      keepGoing' usesCmd)
211
  ]
212
213
214
215
216
217
218
219
220
221
222
223
 where
  mkCmd (n,a,c) = Command { cmdName = n
                          , cmdAction = a
                          , cmdHidden = False
                          , cmdCompletionFunc = c
                          }

  mkCmdHidden (n,a) = Command { cmdName = n
                              , cmdAction = a
                              , cmdHidden = True
                              , cmdCompletionFunc = noCompletion
                              }
224

dterei's avatar
dterei committed
225
-- We initialize readline (in the interactiveUI function) to use
226
227
228
229
-- 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
230
--
231
232
-- NOTE: in order for us to override the default correctly, any custom entry
-- must be a SUBSET of word_break_chars.
233
word_break_chars :: String
234
235
236
237
word_break_chars = let symbols = "!#$%&*+/<=>?@\\^|-~"
                       specials = "(),;[]`{}"
                       spaces = " \t\n"
                   in spaces ++ specials ++ symbols
238

239
flagWordBreakChars :: String
240
241
242
flagWordBreakChars = " \t\n"


243
244
245
246
247
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
248

249
keepGoingPaths :: ([FilePath] -> InputT GHCi ()) -> (String -> InputT GHCi Bool)
Ian Lynagh's avatar
Ian Lynagh committed
250
251
keepGoingPaths a str
 = do case toArgs str of
Ian Lynagh's avatar
Ian Lynagh committed
252
          Left err -> liftIO $ hPutStrLn stderr err
Ian Lynagh's avatar
Ian Lynagh committed
253
254
          Right args -> a args
      return False
sof's avatar
sof committed
255

256
257
defShortHelpText :: String
defShortHelpText = "use :? for help.\n"
258

259
260
defFullHelpText :: String
defFullHelpText =
dterei's avatar
dterei committed
261
262
263
264
265
266
267
268
269
270
  " 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" ++
271
  "   :complete <dom> [<rng>] <s> list completions for partial input string\n" ++
272
  "   :ctags[!] [<file>]          create tags file <file> for Vi (default: \"tags\")\n" ++
dterei's avatar
dterei committed
273
  "                               (!: use regex instead of line number)\n" ++
274
275
  "   :def <cmd> <expr>           define command :<cmd> (later defined command has\n" ++
  "                               precedence, ::<cmd> is always a builtin command)\n" ++
dterei's avatar
dterei committed
276
277
  "   :edit <file>                edit file\n" ++
  "   :edit                       edit last module\n" ++
278
  "   :etags [<file>]             create tags file <file> for Emacs (default: \"TAGS\")\n" ++
dterei's avatar
dterei committed
279
  "   :help, :?                   display this list of commands\n" ++
280
281
  "   :info[!] [<name> ...]       display information about the given names\n" ++
  "                               (!: do not filter instances)\n" ++
dterei's avatar
dterei committed
282
  "   :issafe [<mod>]             display safe haskell information of module <mod>\n" ++
283
284
  "   :kind[!] <type>             show the kind of <type>\n" ++
  "                               (!: also print the normalised type)\n" ++
285
286
  "   :load[!] [*]<module> ...    load module(s) and their dependents\n" ++
  "                               (!: defer type errors)\n" ++
dterei's avatar
dterei committed
287
288
289
  "   :main [<arguments> ...]     run the main function with the given arguments\n" ++
  "   :module [+/-] [*]<mod> ...  set the context for expression evaluation\n" ++
  "   :quit                       exit GHCi\n" ++
290
291
  "   :reload[!]                  reload the current module set\n" ++
  "                               (!: defer type errors)\n" ++
dterei's avatar
dterei committed
292
  "   :run function [<arguments> ...] run the function with the given arguments\n" ++
293
  "   :script <file>              run the script <file>\n" ++
dterei's avatar
dterei committed
294
295
296
297
298
299
300
  "   :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" ++
301
  "   :back [<n>]                 go back in the history N steps (after :trace)\n" ++
dterei's avatar
dterei committed
302
303
304
305
306
307
  "   :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" ++
308
  "   :forward [<n>]              go forward in the history N step s(after :back)\n" ++
dterei's avatar
dterei committed
309
310
  "   :history [<n>]              after :trace, show the execution history\n" ++
  "   :list                       show the source code around current breakpoint\n" ++
311
  "   :list <identifier>          show the source code for <identifier>\n" ++
dterei's avatar
dterei committed
312
  "   :list [<module>] <line>     show the source code around line number <line>\n" ++
Austin Seipp's avatar
Austin Seipp committed
313
314
  "   :print [<name> ...]         show a value without forcing its computation\n" ++
  "   :sprint [<name> ...]        simplified version of :print\n" ++
dterei's avatar
dterei committed
315
316
317
318
319
320
  "   :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
321

dterei's avatar
dterei committed
322
323
324
325
  "\n" ++
  " -- Commands for changing settings:\n" ++
  "\n" ++
  "   :set <option> ...           set options\n" ++
326
  "   :seti <option> ...          set options for interactive evaluation only\n" ++
dterei's avatar
dterei committed
327
328
329
  "   :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" ++
330
  "   :set prompt2 <prompt>       set the continuation prompt used in GHCi\n" ++
dterei's avatar
dterei committed
331
332
333
334
335
336
  "   :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
337
  "    +m            allow multiline commands\n" ++
dterei's avatar
dterei committed
338
339
340
  "    +r            revert top-level expressions after each evaluation\n" ++
  "    +s            print timing/memory stats after each evaluation\n" ++
  "    +t            print type after evaluation\n" ++
341
  "    +c            collect type/location info after loading modules\n" ++
dterei's avatar
dterei committed
342
  "    -<flags>      most GHC command line flags can also be set here\n" ++
343
  "                         (eg. -v2, -XFlexibleInstances, etc.)\n" ++
dterei's avatar
dterei committed
344
345
346
347
348
349
350
351
  "                    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" ++
352
  "   :show imports               show the current imports\n" ++
353
  "   :show linker                show current linker state\n" ++
dterei's avatar
dterei committed
354
355
  "   :show modules               show the currently loaded modules\n" ++
  "   :show packages              show the currently active package flags\n" ++
356
  "   :show paths                 show the currently active search paths\n" ++
357
  "   :show language              show the currently active language flags\n" ++
dterei's avatar
dterei committed
358
359
  "   :show <setting>             show value of <setting>, which is one of\n" ++
  "                                  [args, prog, prompt, editor, stop]\n" ++
360
  "   :showi language             show language flags for interactive evaluation\n" ++
dterei's avatar
dterei committed
361
  "\n"
362

Simon Marlow's avatar
Simon Marlow committed
363
findEditor :: IO String
Simon Marlow's avatar
Simon Marlow committed
364
findEditor = do
dterei's avatar
dterei committed
365
  getEnv "EDITOR"
366
    `catchIO` \_ -> do
367
#if mingw32_HOST_OS
Ian Lynagh's avatar
Ian Lynagh committed
368
369
        win <- System.Win32.getWindowsDirectory
        return (win </> "notepad.exe")
Simon Marlow's avatar
Simon Marlow committed
370
#else
Ian Lynagh's avatar
Ian Lynagh committed
371
        return ""
Simon Marlow's avatar
Simon Marlow committed
372
373
#endif

374
default_progname, default_prompt, default_prompt2, default_stop :: String
Boris Lykah's avatar
Boris Lykah committed
375
default_progname = "<interactive>"
376
377
default_prompt = "%s> "
default_prompt2 = "%s| "
Boris Lykah's avatar
Boris Lykah committed
378
379
default_stop = ""

Simon Marlow's avatar
Simon Marlow committed
380
381
382
default_args :: [String]
default_args = []

383
interactiveUI :: GhciSettings -> [(FilePath, Maybe Phase)] -> Maybe [String]
384
              -> Ghc ()
385
interactiveUI config srcs maybe_exprs = do
386
387
388
389
390
391
392
393
   -- 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.
394
395
396
   _ <- liftIO $ newStablePtr stdin
   _ <- liftIO $ newStablePtr stdout
   _ <- liftIO $ newStablePtr stderr
397

Ian Lynagh's avatar
Ian Lynagh committed
398
    -- Initialise buffering for the *interpreted* I/O system
399
   (nobuffering, flush) <- initInterpBuffering
400

401
   -- The initial set of DynFlags used for interactive evaluation is the same
402
403
   -- as the global DynFlags, plus -XExtendedDefaultRules and
   -- -XNoMonomorphismRestriction.
404
   dflags <- getDynFlags
405
406
   let dflags' = (`xopt_set` LangExt.ExtendedDefaultRules)
               . (`xopt_unset` LangExt.MonomorphismRestriction)
407
408
               $ dflags
   GHC.setInteractiveDynFlags dflags'
409

410
411
412
413
414
   lastErrLocationsRef <- liftIO $ newIORef []
   progDynFlags <- GHC.getProgramDynFlags
   _ <- GHC.setProgramDynFlags $
      progDynFlags { log_action = ghciLogAction lastErrLocationsRef }

415
   when (isNothing maybe_exprs) $ do
Ian Lynagh's avatar
Ian Lynagh committed
416
417
418
        -- Only for GHCi (not runghc and ghc -e):

        -- Turn buffering off for the compiled program's stdout/stderr
419
        turnOffBuffering_ nobuffering
Ian Lynagh's avatar
Ian Lynagh committed
420
        -- Turn buffering off for GHCi's stdout
421
422
        liftIO $ hFlush stdout
        liftIO $ hSetBuffering stdout NoBuffering
Ian Lynagh's avatar
Ian Lynagh committed
423
424
        -- We don't want the cmd line to buffer any input that might be
        -- intended for the program, so unbuffer stdin.
425
426
        liftIO $ hSetBuffering stdin NoBuffering
        liftIO $ hSetBuffering stderr NoBuffering
427
#if defined(mingw32_HOST_OS)
428
429
430
        -- 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.
431
        liftIO $ hSetEncoding stdin utf8
432
#endif
Ian Lynagh's avatar
Ian Lynagh committed
433

434
   default_editor <- liftIO $ findEditor
435
   eval_wrapper <- mkEvalWrapper default_progname default_args
Ian Lynagh's avatar
Ian Lynagh committed
436
   startGHCi (runGHCi srcs maybe_exprs)
437
        GHCiState{ progname           = default_progname,
438
                   args               = default_args,
439
                   evalWrapper        = eval_wrapper,
440
441
                   prompt             = defPrompt config,
                   prompt2            = defPrompt2 config,
442
443
444
                   stop               = default_stop,
                   editor             = default_editor,
                   options            = [],
445
446
447
448
                   -- We initialize line number as 0, not 1, because we use
                   -- current line number while reporting errors which is
                   -- incremented after reading a line.
                   line_number        = 0,
449
450
451
452
453
454
455
456
457
458
459
                   break_ctr          = 0,
                   breaks             = [],
                   tickarrays         = emptyModuleEnv,
                   ghci_commands      = availableCommands config,
                   last_command       = Nothing,
                   cmdqueue           = [],
                   remembered_ctx     = [],
                   transient_ctx      = [],
                   ghc_e              = isJust maybe_exprs,
                   short_help         = shortHelpText config,
                   long_help          = fullHelpText config,
460
                   lastErrorLocations = lastErrLocationsRef,
461
                   mod_infos          = M.empty,
462
463
                   flushStdHandles    = flush,
                   noBuffering        = nobuffering
mnislaih's avatar
mnislaih committed
464
                 }
465

466
467
   return ()

468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
resetLastErrorLocations :: GHCi ()
resetLastErrorLocations = do
    st <- getGHCiState
    liftIO $ writeIORef (lastErrorLocations st) []

ghciLogAction :: IORef [(FastString, Int)] ->  LogAction
ghciLogAction lastErrLocations dflags severity srcSpan style msg = do
    defaultLogAction dflags severity srcSpan style msg
    case severity of
        SevError -> case srcSpan of
            RealSrcSpan rsp -> modifyIORef lastErrLocations
                (++ [(srcLocFile (realSrcSpanStart rsp), srcLocLine (realSrcSpanStart rsp))])
            _ -> return ()
        _ -> return ()

483
484
withGhcAppData :: (FilePath -> IO a) -> IO a -> IO a
withGhcAppData right left = do
485
    either_dir <- tryIO (getAppUserDataDirectory "ghc")
486
487
488
489
490
    case either_dir of
        Right dir ->
            do createDirectoryIfMissing False dir `catchIO` \_ -> return ()
               right dir
        _ -> left
491

Ian Lynagh's avatar
Ian Lynagh committed
492
493
runGHCi :: [(FilePath, Maybe Phase)] -> Maybe [String] -> GHCi ()
runGHCi paths maybe_exprs = do
494
  dflags <- getDynFlags
495
  let
496
   ignore_dot_ghci = gopt Opt_IgnoreDotGhci dflags
497

498
499
   current_dir = return (Just ".ghci")

Ian Lynagh's avatar
Ian Lynagh committed
500
   app_user_dir = liftIO $ withGhcAppData
501
502
                    (\dir -> return (Just (dir </> "ghci.conf")))
                    (return Nothing)
503
504

   home_dir = do
505
    either_dir <- liftIO $ tryIO (getEnv "HOME")
506
507
508
509
    case either_dir of
      Right home -> return (Just (home </> ".ghci"))
      _ -> return Nothing

510
511
512
513
   canonicalizePath' :: FilePath -> IO (Maybe FilePath)
   canonicalizePath' fp = liftM Just (canonicalizePath fp)
                `catchIO` \_ -> return Nothing

514
515
   sourceConfigFile :: FilePath -> GHCi ()
   sourceConfigFile file = do
Ian Lynagh's avatar
Ian Lynagh committed
516
     exists <- liftIO $ doesFileExist file
517
     when exists $ do
518
519
520
521
522
523
524
525
526
527
528
       either_hdl <- liftIO $ tryIO (openFile file ReadMode)
       case either_hdl of
         Left _e   -> return ()
         -- 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.
         Right hdl ->
             do runInputTWithPrefs defaultPrefs defaultSettings $
                          runCommands $ fileLoop hdl
                liftIO (hClose hdl `catchIO` \_ -> return ())

529
530
  --

531
  setGHCContextFromGHCiState
Ian Lynagh's avatar
Ian Lynagh committed
532

533
534
  dot_cfgs <- if ignore_dot_ghci then return [] else do
    dot_files <- catMaybes <$> sequence [ current_dir, app_user_dir, home_dir ]
535
    liftIO $ filterM checkFileAndDirPerms dot_files
536
537
538
539
540
541
542
  let arg_cfgs = reverse $ ghciScripts dflags
    -- -ghci-script are collected in reverse order
  mcfgs <- liftIO $ mapM canonicalizePath' $ dot_cfgs ++ arg_cfgs
    -- We don't require that a script explicitly added by -ghci-script
    -- is owned by the current user. (#6017)
  mapM_ sourceConfigFile $ nub $ catMaybes mcfgs
    -- nub, because we don't want to read .ghci twice if the CWD is $HOME.
543

544
  -- Perform a :load for files given on the GHCi command line
545
546
547
  -- 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
548
     ok <- ghciHandle (\e -> do showException e; return Failed) $
549
                -- TODO: this is a hack.
550
551
                runInputTWithPrefs defaultPrefs defaultSettings $
                    loadModule paths
Ian Lynagh's avatar
Ian Lynagh committed
552
     when (isJust maybe_exprs && failed ok) $
Ian Lynagh's avatar
Ian Lynagh committed
553
        liftIO (exitWith (ExitFailure 1))
554

555
556
  installInteractivePrint (interactivePrint dflags) (isJust maybe_exprs)

557
558
  -- 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
559
  is_tty <- liftIO (hIsTerminalDevice stdin)
560
561
  let show_prompt = verbosity dflags > 0 || is_tty

562
  -- reset line number
563
  modifyGHCiState $ \st -> st{line_number=0}
564

Ian Lynagh's avatar
Ian Lynagh committed
565
  case maybe_exprs of
Ian Lynagh's avatar
Ian Lynagh committed
566
        Nothing ->
sof's avatar
sof committed
567
          do
Ian Lynagh's avatar
Ian Lynagh committed
568
            -- enter the interactive loop
569
            runGHCiInput $ runCommands $ nextInputLine show_prompt is_tty
Ian Lynagh's avatar
Ian Lynagh committed
570
        Just exprs -> do
Ian Lynagh's avatar
Ian Lynagh committed
571
            -- just evaluate the expression we were given
Ian Lynagh's avatar
Ian Lynagh committed
572
            enqueueCommands exprs
dterei's avatar
dterei committed
573
574
575
576
577
578
579
580
            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
581
                                   -- this used to be topHandlerFastExit, see #2228
582
            runInputTWithPrefs defaultPrefs defaultSettings $ do
583
                -- make `ghc -e` exit nonzero on invalid input, see Trac #7962
584
585
586
587
                _ <- runCommands' hdle
                     (Just $ hdle (toException $ ExitFailure 1) >> return ())
                     (return Nothing)
                return ()
588
589

  -- and finally, exit
Ian Lynagh's avatar
Ian Lynagh committed
590
  liftIO $ when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
591

592
593
runGHCiInput :: InputT GHCi a -> GHCi a
runGHCiInput f = do
Ian Lynagh's avatar
Ian Lynagh committed
594
    dflags <- getDynFlags
ian@well-typed.com's avatar
ian@well-typed.com committed
595
    histFile <- if gopt Opt_GhciHistory dflags
Ian Lynagh's avatar
Ian Lynagh committed
596
597
598
                then liftIO $ withGhcAppData (\dir -> return (Just (dir </> "ghci_history")))
                                             (return Nothing)
                else return Nothing
dterei's avatar
dterei committed
599
600
601
    runInputT
        (setComplete ghciCompleteWord $ defaultSettings {historyFile = histFile})
        f
602

603
-- | How to get the next input line from the user
604
605
606
nextInputLine :: Bool -> Bool -> InputT GHCi (Maybe String)
nextInputLine show_prompt is_tty
  | is_tty = do
dterei's avatar
dterei committed
607
608
    prmpt <- if show_prompt then lift mkPrompt else return ""
    r <- getInputLine prmpt
609
610
    incrementLineNo
    return r
611
612
613
  | otherwise = do
    when show_prompt $ lift mkPrompt >>= liftIO . putStr
    fileLoop stdin
614

615
-- NOTE: We only read .ghci files if they are owned by the current user,
616
617
618
-- and aren't world writable (files owned by root are ok, see #9324).
-- Otherwise, we could be accidentally running code planted by
-- a malicious third party.
619

rrt's avatar
rrt committed
620
621
622
623
-- 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.
624

625
626
checkFileAndDirPerms :: FilePath -> IO Bool
checkFileAndDirPerms file = do
627
  file_ok <- checkPerms file
thomie's avatar
thomie committed
628
629
630
631
  -- Do not check dir perms when .ghci doesn't exist, otherwise GHCi will
  -- print some confusing and useless warnings in some cases (e.g. in
  -- travis). Note that we can't add a test for this, as all ghci tests should
  -- run with -ignore-dot-ghci, which means we never get here.
632
  if file_ok then checkPerms (getDirectory file) else return False
633
634
635
636
637
638
  where
  getDirectory f = case takeDirectory f of
    "" -> "."
    d -> d

checkPerms :: FilePath -> IO Bool
639
#ifdef mingw32_HOST_OS
dterei's avatar
dterei committed
640
checkPerms _ = return True
sof's avatar
sof committed
641
#else
642
checkPerms file =
643
  handleIO (\_ -> return False) $ do
644
    st <- getFileStatus file
dterei's avatar
dterei committed
645
    me <- getRealUserID
646
647
648
649
650
    let mode = System.Posix.fileMode st
        ok = (fileOwner st == me || fileOwner st == 0) &&
             groupWriteMode /= mode `intersectFileModes` groupWriteMode &&
             otherWriteMode /= mode `intersectFileModes` otherWriteMode
    unless ok $
651
      -- #8248: Improving warning to include a possible fix.
652
      putStrLn $ "*** WARNING: " ++ file ++
653
                 " is writable by someone else, IGNORING!" ++
Ben Gamari's avatar
Ben Gamari committed
654
                 "\nSuggested fix: execute 'chmod go-w " ++ file ++ "'"
655
    return ok
sof's avatar
sof committed
656
#endif
657

658
incrementLineNo :: InputT GHCi ()
659
660
661
incrementLineNo = modifyGHCiState incLineNo
  where
    incLineNo st = st { line_number = line_number st + 1 }
vivian's avatar
vivian committed
662
663

fileLoop :: Handle -> InputT GHCi (Maybe String)
664
fileLoop hdl = do
665
   l <- liftIO $ tryIO $ hGetLine hdl
666
   case l of
667
        Left e | isEOFError e              -> return Nothing
668
669
670
671
672
               | -- as we share stdin with the program, the program
                 -- might have already closed it, so we might get a
                 -- handle-closed exception. We therefore catch that
                 -- too.
                 isIllegalOperation e      -> return Nothing
673
               | InvalidArgument <- etype  -> return Nothing
674
               | otherwise                 -> liftIO $ ioError e
675
676
677
678
679
                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
680
        Right l' -> do
681
           incrementLineNo
dterei's avatar
dterei committed
682
           return (Just l')
683

Simon Marlow's avatar
Simon Marlow committed
684
mkPrompt :: GHCi String
685
mkPrompt = do
686
  st <- getGHCiState
687
  imports <- GHC.getContext
688
  resumes <- GHC.getResumeContext
689
690
691
692

  context_bit <-
        case resumes of
            [] -> return empty
Simon Marlow's avatar
Simon Marlow committed
693
            r:_ -> do
694
695
696
697
698
                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
699
700
701
                        pan <- GHC.getHistorySpan hist
                        return (brackets (ppr (negate ix) <> char ':'
                                          <+> ppr pan) <> space)
702
  let
Simon Marlow's avatar
Simon Marlow committed
703
        dots | _:rs <- resumes, not (null rs) = text "... "
704
705
             | otherwise = empty

706
        rev_imports = reverse imports -- rightmost are the most recent
707
708
709
        modules_bit =
             hsep [ char '*' <> ppr m | IIModule m <- rev_imports ] <+>
             hsep (map ppr [ myIdeclName d | IIDecl d <- rev_imports ])
710
711
712
713

         --  use the 'as' name if there is one
        myIdeclName d | Just m <- ideclAs d = m
                      | otherwise           = unLoc (ideclName d)
714

715
        deflt_prompt = dots <> context_bit <> modules_bit
716

717
        f ('%':'l':xs) = ppr (1 + line_number st) <> f xs
718
719
720
721
        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
722

723
724
  dflags <- getDynFlags
  return (showSDoc dflags (f (prompt st)))
725

726

727
728
729
730
731
732
733
734
queryQueue :: GHCi (Maybe String)
queryQueue = do
  st <- getGHCiState
  case cmdqueue st of
    []   -> return Nothing
    c:cs -> do setGHCiState st{ cmdqueue = cs }
               return (Just c)

735
736
737
738
739
740
-- 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
741
                modifySession (\he -> let new_ic = setInteractivePrintName (hsc_IC he) name
742
                                      in he{hsc_IC = new_ic})
743
744
745
746
                return Succeeded

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

747
-- | The main read-eval-print loop
748
runCommands :: InputT GHCi (Maybe String) -> InputT GHCi ()
749
runCommands gCmd = runCommands' handler Nothing gCmd >> return ()
750

dterei's avatar
dterei committed
751
runCommands' :: (SomeException -> GHCi Bool) -- ^ Exception handler
752
             -> Maybe (GHCi ()) -- ^ Source error handler
753
754
755
756
757
758
             -> InputT GHCi (Maybe String)
             -> InputT GHCi (Maybe Bool)
         -- We want to return () here, but have to return (Maybe Bool)
         -- because gmask is not polymorphic enough: we want to use
         -- unmask at two different types.
runCommands' eh sourceErrorHandler gCmd = gmask $ \unmask -> do
759
    b <- ghandle (\e -> case fromException e of
vivian's avatar
vivian committed
760
                          Just UserInterrupt -> return $ Just False
761
                          _ -> case fromException e of
dterei's avatar
dterei committed
762
763
                                 Just ghce ->
                                   do liftIO (print (ghce :: GhcException))
vivian's avatar
vivian committed
764
                                      return Nothing
765
766
                                 _other ->
                                   liftIO (Exception.throwIO e))
767
            (unmask $ runOneCommand eh gCmd)
vivian's avatar
vivian committed
768
    case b of
769
      Nothing -> return Nothing
770
      Just success -> do
771
        unless success $ maybe (return ()) lift sourceErrorHandler
772
        unmask $ runCommands' eh sourceErrorHandler gCmd
773

774
775
776
777
778
-- | Evaluate a single line of user input (either :<command> or Haskell code).
-- A result of Nothing means there was no more input to process.
-- Otherwise the result is Just b where b is True if the command succeeded;
-- this is relevant only to ghc -e, which will exit with status 1
-- if the commmand was unsuccessful. GHCi will continue in either case.
779
runOneCommand :: (SomeException -> GHCi Bool) -> InputT GHCi (Maybe String)
vivian's avatar
vivian committed
780
            -> InputT GHCi (Maybe Bool)
dterei's avatar
dterei committed
781
runOneCommand eh gCmd = do
782
783
  -- run a previously queued command if there is one, otherwise get new
  -- input from user
dterei's avatar
dterei committed
784
785
786
  mb_cmd0 <- noSpace (lift queryQueue)
  mb_cmd1 <- maybe (noSpace gCmd) (return . Just) mb_cmd0
  case mb_cmd1 of
vivian's avatar
vivian committed
787
788
    Nothing -> return Nothing
    Just c  -> ghciHandle (\e -> lift $ eh e >>= return . Just) $
789
             handleSourceError printErrorAndFail
790
               (doCommand c)
vivian's avatar
vivian committed
791
792
               -- source error's are handled by runStmt
               -- is the handler necessary here?
793
  where
794
    printErrorAndFail err = do
795
        GHC.printException err
796
        return $ Just False     -- Exit ghc -e, but not GHCi
797

798
    noSpace q = q >>= maybe (return Nothing)
dterei's avatar
dterei committed
799
800
801
                            (\c -> case removeSpaces c of
                                     ""   -> noSpace q
                                     ":{" -> multiLineCmd q
802
                                     _    -> return (Just c) )
803
    multiLineCmd q = do
804
      st <- getGHCiState
805
      let p = prompt st
806
807
808
      setGHCiState st{ prompt = prompt2 st }
      mb_cmd <- collectCommand q "" `GHC.gfinally`
                modifyGHCiState (\st' -> st' { prompt = p })
809
      return mb_cmd
dterei's avatar
dterei committed
810
    -- we can't use removeSpaces for the sublines here, so
811
    -- multiline commands are somewhat more brittle against
dterei's avatar
dterei committed
812
813
    -- fileformat errors (such as \r in dos input on unix),
    -- we get rid of any extra spaces for the ":}" test;
814
    -- we also avoid silent failure if ":}" is not found;
dterei's avatar
dterei committed
815
    -- and since there is no (?) valid occurrence of \r (as
816
817
    -- opposed to its String representation, "\r") inside a
    -- ghci command, we replace any such with ' ' (argh:-(
dterei's avatar
dterei committed
818
    collectCommand q c = q >>=
819
      maybe (liftIO (ioError collectError))
dterei's avatar
dterei committed
820
            (\l->if removeSpaces l == ":}"
821
                 then return (Just c)
822
                 else collectCommand q (c ++ "\n" ++ map normSpace l))
823
      where normSpace '\r' = ' '
dterei's avatar
dterei committed
824
            normSpace   x  = x
dterei's avatar
dterei committed
825
    -- SDM (2007-11-07): is userError the one to use here?
826
    collectError = userError "unterminated multiline command :{ .. :}"
827
828
829
830
831

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

    -- command
832
    doCommand stmt | (':' : cmd) <- removeSpaces stmt = do
vivian's avatar
vivian committed
833
834
835
836
      result <- specialCommand cmd
      case result of
        True -> return Nothing
        _    -> return $ Just True
837
838
839

    -- haskell
    doCommand stmt = do
840
841
      -- if 'stmt' was entered via ':{' it will contain '\n's
      let stmt_nl_cnt = length [ () | '\n' <- stmt ]
vivian's avatar
vivian committed
842
      ml <- lift $ isOptionSet Multiline
843
      if ml && stmt_nl_cnt == 0 -- don't trigger automatic multi-line mode for ':{'-multiline input
dterei's avatar
dterei committed
844
        then do
845
          fst_line_num <- line_number <$> getGHCiState
dterei's avatar
dterei committed
846
          mb_stmt <- checkInputForLayout stmt gCmd
vivian's avatar
vivian committed
847
848
849
          case mb_stmt of
            Nothing      -> return $ Just True
            Just ml_stmt -> do
850
              -- temporarily compensate line-number for multi-line input
851
852
853
854
              result <- timeIt runAllocs $ lift $
                runStmtWithLineNum fst_line_num ml_stmt GHC.RunToCompletion
              return $ Just (runSuccess result)
        else do -- single line input and :{ - multiline input
855
          last_line_num <- line_number <$> getGHCiState
856
857
858
859
860
861
          -- reconstruct first line num from last line num and stmt
          let fst_line_num | stmt_nl_cnt > 0 = last_line_num - (stmt_nl_cnt2 + 1)
                           | otherwise = last_line_num -- single line input
              stmt_nl_cnt2 = length [ () | '\n' <- stmt' ]
              stmt' = dropLeadingWhiteLines stmt -- runStmt doesn't like leading empty lines
          -- temporarily compensate line-number for multi-line input
862
863
864
          result <- timeIt runAllocs $ lift $
            runStmtWithLineNum fst_line_num stmt' GHC.RunToCompletion
          return $ Just (runSuccess result)
vivian's avatar
vivian committed
865

866
    -- runStmt wrapper for temporarily overridden line-number
867
868
    runStmtWithLineNum :: Int -> String -> SingleStep
                       -> GHCi (Maybe GHC.ExecResult)
869
870
871
872
873
874
875
876
877
878
879
880
881
882
    runStmtWithLineNum lnum stmt step = do
        st0 <- getGHCiState
        setGHCiState st0 { line_number = lnum }
        result <- runStmt stmt step
        -- restore original line_number
        getGHCiState >>= \st -> setGHCiState st { line_number = line_number st0 }
        return result

    -- note: this is subtly different from 'unlines . dropWhile (all isSpace) . lines'
    dropLeadingWhiteLines s | (l0,'\n':r) <- break (=='\n') s
                            , all isSpace l0 = dropLeadingWhiteLines r
                            | otherwise = s


vivian's avatar
vivian committed
883
884
-- #4316
-- lex the input.  If there is an unclosed layout context, request input
vivian's avatar
vivian committed
885
checkInputForLayout :: String -> InputT GHCi (Maybe String)
vivian's avatar
vivian committed
886
                    -> InputT GHCi (Maybe String)
vivian's avatar
vivian committed
887
checkInputForLayout stmt getStmt = do
888
   dflags' <- getDynFlags
889
   let dflags =