aboutsummaryrefslogtreecommitdiff
path: root/Distribution/Helper.hs
blob: 7bd76e904e2f4844fd95b89fa6b23049075772f6 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
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
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
-- ghc-mod: Making Haskell development *more* fun
-- Copyright (C) 2015  Daniel Gröber <dxld ÄT darkboxed DOT org>
--
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU Affero General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU Affero General Public License for more details.
--
-- You should have received a copy of the GNU Affero General Public License
-- along with this program.  If not, see <http://www.gnu.org/licenses/>.

{-# LANGUAGE CPP, RecordWildCards, FlexibleContexts, ConstraintKinds #-}
{-# LANGUAGE GeneralizedNewtypeDeriving, DeriveDataTypeable, DeriveGeneric #-}

module Distribution.Helper (
    Programs(..)
  , defaultPrograms
  , QueryEnv
  , qeReadProcess
  , qePrograms
  , qeProjectDir
  , qeDistDir
  , qeCabalPkgDb
  , qeCabalVer
  , defaultQueryEnv

  -- * Running Queries
  , Query
  , runQuery

  -- * Queries against Cabal\'s on disk state

  , packageDbStack
  , entrypoints
  , sourceDirs
  , ghcOptions
  , ghcSrcOptions
  , ghcPkgOptions
  , ghcMergedPkgOptions
  , ghcLangOptions
  , pkgLicenses
  , flags
  , configFlags
  , nonDefaultConfigFlags
  , packageId
  , compilerVersion

  -- * Result types
  , ChModuleName(..)
  , ChComponentName(..)
  , ChPkgDb(..)
  , ChEntrypoint(..)

  -- * General information
  , buildPlatform

  -- * Stuff that cabal-install really should export
  , Distribution.Helper.getSandboxPkgDb

  -- * Managing @dist/@
  , prepare
  , prepare'
  , reconfigure
  , writeAutogenFiles
  , writeAutogenFiles'

  -- * $libexec related error handling
  , LibexecNotFoundError(..)
  , libexecNotFoundError
  ) where

import Control.Applicative
import Control.Monad
import Control.Monad.IO.Class
import Control.Monad.State.Strict
import Control.Monad.Reader
import Control.Exception as E
import Data.Char
import Data.List
import Data.Maybe
import Data.Version
import Data.Typeable
import Distribution.Simple.BuildPaths (exeExtension)
import System.Environment
import System.FilePath
import System.Directory
import System.Process
import System.IO.Unsafe
import Text.Printf
import GHC.Generics
import Prelude

import Paths_cabal_helper (getLibexecDir)
import CabalHelper.Shared.Types hiding (Options(..))
import CabalHelper.Shared.Sandbox

-- | Paths or names of various programs we need.
data Programs = Programs {
      cabalProgram  :: FilePath,
      ghcProgram    :: FilePath,
      ghcPkgProgram :: FilePath
    } deriving (Eq, Ord, Show, Read, Generic, Typeable)

defaultPrograms :: Programs
defaultPrograms = Programs "cabal" "ghc" "ghc-pkg"

data QueryEnv = QueryEnv {
      -- | How to start the cabal-helper process. Useful if you need to
      -- capture stderr output from the helper.
      qeReadProcess :: FilePath -> [String] -> String -> IO String,

      qePrograms    :: Programs,

      -- | Path to project directory, i.e. the one containing the
      -- @project.cabal@ file
      qeProjectDir  :: FilePath,

      -- | Path to the @dist/@ directory
      qeDistDir     :: FilePath,

      -- | Where to look for the Cabal library when linking the helper
      qeCabalPkgDb  :: Maybe FilePath,

      -- | If @dist/setup-config@ wasn\'t written by this version of Cabal throw
      -- an error
      qeCabalVer    :: Maybe Version
    }

defaultQueryEnv :: FilePath
                -- ^ Path to project directory, i.e. the one containing the
                -- @project.cabal@ file
                -> FilePath
                -- ^ Path to the @dist/@ directory
                -> QueryEnv
defaultQueryEnv projdir distdir = QueryEnv {
    qeReadProcess = readProcess
  , qePrograms    = defaultPrograms
  , qeProjectDir  = projdir
  , qeDistDir     = distdir
  , qeCabalPkgDb  = Nothing
  , qeCabalVer    = Nothing
  }

data SomeLocalBuildInfo = SomeLocalBuildInfo {
      slbiPackageDbStack      :: [ChPkgDb],
      slbiEntrypoints         :: [(ChComponentName, ChEntrypoint)],
      slbiSourceDirs          :: [(ChComponentName, [String])],
      slbiGhcOptions          :: [(ChComponentName, [String])],
      slbiGhcSrcOptions       :: [(ChComponentName, [String])],
      slbiGhcPkgOptions       :: [(ChComponentName, [String])],
      slbiGhcMergedPkgOptions :: [String],
      slbiGhcLangOptions      :: [(ChComponentName, [String])],
      slbiPkgLicenses         :: [(String, [(String, Version)])],
      slbiFlags               :: [(String, Bool)],
      slbiConfigFlags         :: [(String, Bool)],
      slbiNonDefaultConfigFlags :: [(String, Bool)],
      slbiCompilerVersion     :: (String, Version)
    } deriving (Eq, Ord, Read, Show)

-- | Caches helper executable result so it doesn't have to be run more than once
-- as reading in Cabal's @LocalBuildInfo@ datatype from disk is very slow but
-- running all possible queries against it at once is cheap.
newtype Query m a = Query { unQuery :: StateT (Maybe SomeLocalBuildInfo)
                                         (ReaderT QueryEnv m) a }
    deriving (Functor, Applicative, Monad, MonadIO)

instance MonadTrans Query where
    lift = Query . lift . lift

type MonadQuery m = ( MonadIO m
                    , MonadState (Maybe SomeLocalBuildInfo) m
                    , MonadReader QueryEnv m)

run :: Monad m => QueryEnv -> Maybe SomeLocalBuildInfo -> Query m a -> m a
run e s action = flip runReaderT e (flip evalStateT s (unQuery action))

-- | @runQuery query distdir@. Run a 'Query'. @distdir@ is where Cabal's
-- @setup-config@ file is located.
runQuery :: Monad m
         => QueryEnv
         -> Query m a
         -> m a
runQuery qe action = run qe Nothing action

getSlbi :: MonadQuery m => m SomeLocalBuildInfo
getSlbi = do
  s <- get
  case s of
    Nothing -> do
            slbi <- getSomeConfigState
            put (Just slbi)
            return slbi
    Just slbi -> return slbi

-- | List of package databases to use.
packageDbStack :: MonadIO m => Query m [ChPkgDb]

-- | Modules or files Cabal would have the compiler build directly. Can be used
-- to compute the home module closure for a component.
entrypoints   :: MonadIO m => Query m [(ChComponentName, ChEntrypoint)]

-- | A component's @source-dirs@ field, beware as if this is empty implicit
-- behaviour in GHC kicks in.
sourceDirs    :: MonadIO m => Query m [(ChComponentName, [FilePath])]

-- | All options cabal would pass to GHC.
ghcOptions    :: MonadIO m => Query m [(ChComponentName, [String])]

-- | Only search path related GHC options.
ghcSrcOptions :: MonadIO m => Query m [(ChComponentName, [String])]

-- | Only package related GHC options, sufficient for things don't need to
-- access any home modules.
ghcPkgOptions :: MonadIO m => Query m [(ChComponentName, [String])]

-- | Like @ghcPkgOptions@ but for the whole package not just one component
ghcMergedPkgOptions :: MonadIO m => Query m [String]

-- | Only language related options, i.e. @-XSomeExtension@
ghcLangOptions :: MonadIO m => Query m [(ChComponentName, [String])]

-- | Get the licenses of the packages the current project is linking against.
pkgLicenses :: MonadIO m => Query m [(String, [(String, Version)])]

-- | Flag definitions from cabal file
flags :: MonadIO m => Query m [(String, Bool)]

-- | Flag assignments from setup-config
configFlags :: MonadIO m => Query m [(String, Bool)]

-- | Flag assignments from setup-config which differ from the default
-- setting. This can also include flags which cabal decided to modify,
-- i.e. don't rely on these being the flags set by the user directly.
nonDefaultConfigFlags :: MonadIO m => Query m [(String, Bool)]

-- | The version of GHC the project is configured to use
compilerVersion :: MonadIO m => Query m (String, Version)

-- | Package identifier, i.e. package name and version
packageId :: MonadIO m => Query m (String, Version)


packageDbStack      = Query $ slbiPackageDbStack      `liftM` getSlbi
entrypoints         = Query $ slbiEntrypoints         `liftM` getSlbi
sourceDirs          = Query $ slbiSourceDirs          `liftM` getSlbi
ghcOptions          = Query $ slbiGhcOptions          `liftM` getSlbi
ghcSrcOptions       = Query $ slbiGhcSrcOptions       `liftM` getSlbi
ghcPkgOptions       = Query $ slbiGhcPkgOptions       `liftM` getSlbi
ghcMergedPkgOptions = Query $ slbiGhcMergedPkgOptions `liftM` getSlbi
ghcLangOptions      = Query $ slbiGhcLangOptions      `liftM` getSlbi
pkgLicenses         = Query $ slbiPkgLicenses         `liftM` getSlbi
flags               = Query $ slbiFlags               `liftM` getSlbi
configFlags         = Query $ slbiConfigFlags         `liftM` getSlbi
nonDefaultConfigFlags = Query $ slbiNonDefaultConfigFlags `liftM` getSlbi
compilerVersion     = Query $ slbiCompilerVersion     `liftM` getSlbi
packageId           = Query $ getPackageId

-- | Run @cabal configure@
reconfigure :: MonadIO m
            => (FilePath -> [String] -> String -> IO String)
            -> Programs -- ^ Program paths
            -> [String] -- ^ Command line arguments to be passed to @cabal@
            -> m ()
reconfigure readProc progs cabalOpts = do
    let progOpts =
            [ "--with-ghc=" ++ ghcProgram progs ]
            -- Only pass ghc-pkg if it was actually set otherwise we
            -- might break cabal's guessing logic
            ++ if ghcPkgProgram progs /= "ghc-pkg"
                 then [ "--with-ghc-pkg=" ++ ghcPkgProgram progs ]
                 else []
            ++ cabalOpts
    _ <- liftIO $ readProc (cabalProgram progs) ("configure":progOpts) ""
    return ()

readHelper :: (MonadIO m, MonadQuery m) => [String] -> m [Maybe ChResponse]
readHelper args = ask >>= \qe -> liftIO $ do
  out <- either error id <$> invokeHelper qe args
  let res = read out
  liftIO $ evaluate res `E.catch` \se@(SomeException _) -> do
      md <- lookupEnv' "CABAL_HELPER_DEBUG"
      let msg = "readHelper: exception: '" ++ show se ++ "'"
      error $ msg ++ case md of
        Nothing -> ", for more information set the environment variable CABAL_HELPER_DEBUG"
        Just _ -> ", output: '"++ out ++"'"

invokeHelper :: QueryEnv -> [String] -> IO (Either String String)
invokeHelper QueryEnv {..} args = do
  let progArgs = [ "--with-ghc="     ++ ghcProgram qePrograms
                 , "--with-ghc-pkg=" ++ ghcPkgProgram qePrograms
                 , "--with-cabal="   ++ cabalProgram qePrograms
                 ]
  exe  <- findLibexecExe
  let args' = progArgs ++ qeProjectDir:qeDistDir:args
  out <- qeReadProcess exe args' ""
  (Right <$> evaluate out) `E.catch` \(SomeException _) ->
      return $ Left $ concat
                 ["invokeHelper", ": ", exe, " "
                 , intercalate " " (map show args')
                 , " failed"
                 ]


getPackageId :: MonadQuery m => m (String, Version)
getPackageId = ask >>= \QueryEnv {..} -> do
  [ Just (ChResponseVersion pkgName pkgVer) ] <- readHelper [ "package-id" ]
  return (pkgName, pkgVer)


getSomeConfigState :: MonadQuery m => m SomeLocalBuildInfo
getSomeConfigState = ask >>= \QueryEnv {..} -> do
  res <- readHelper
         [ "package-db-stack"
         , "entrypoints"
         , "source-dirs"
         , "ghc-options"
         , "ghc-src-options"
         , "ghc-pkg-options"
         , "ghc-merged-pkg-options"
         , "ghc-lang-options"
         , "licenses"
         , "flags"
         , "config-flags"
         , "non-default-config-flags"
         , "compiler-version"
         ]
  let [ Just (ChResponsePkgDbs pkgDbs),
        Just (ChResponseEntrypoints eps),
        Just (ChResponseCompList srcDirs),
        Just (ChResponseCompList ghcOpts),
        Just (ChResponseCompList ghcSrcOpts),
        Just (ChResponseCompList ghcPkgOpts),
        Just (ChResponseList     ghcMergedPkgOpts),
        Just (ChResponseCompList ghcLangOpts),
        Just (ChResponseLicenses pkgLics),
        Just (ChResponseFlags fls),
        Just (ChResponseFlags cfls),
        Just (ChResponseFlags ndcfls),
        Just (ChResponseVersion comp compVer)
        ] = res

  return $ SomeLocalBuildInfo
    pkgDbs eps srcDirs ghcOpts ghcSrcOpts ghcPkgOpts ghcMergedPkgOpts ghcLangOpts pkgLics fls cfls ndcfls (comp, compVer)

prepare :: MonadIO m
        => (FilePath -> [String] -> String -> IO String)
        -> FilePath
        -> FilePath
        -> m ()
prepare readProc projdir distdir = liftIO $ do
  exe  <- findLibexecExe
  void $ readProc exe [projdir, distdir] ""

{-# DEPRECATED prepare
  "Will be replaced by prepare' in the next major release" #-}

-- | Make sure the appropriate helper executable for the given project is
-- installed and ready to run queries.
prepare' :: MonadIO m => QueryEnv -> m ()
prepare' qe =
  liftIO $ void $ invokeHelper qe []

writeAutogenFiles :: MonadIO m
                  => (FilePath -> [String] -> String -> IO String)
                  -> FilePath
                  -- ^ Path to project directory, i.e. the one containing the
                  -- @project.cabal@ file
                  -> FilePath
                  -- ^ Path to the @dist/@ directory
                  -> m ()
writeAutogenFiles readProc projdir distdir = liftIO $ do
  exe  <- findLibexecExe
  void $ readProc exe [projdir, distdir, "write-autogen-files"] ""

{-# DEPRECATED writeAutogenFiles
  "Will be replaced by writeAutogenFiles' in the next major release" #-}

-- | Create @cabal_macros.h@ and @Paths_\<pkg\>@ possibly other generated files
-- in the usual place.
writeAutogenFiles' :: MonadIO m => QueryEnv -> m ()
writeAutogenFiles' qe  =
  liftIO $ void $ invokeHelper qe ["write-autogen-files"]

-- | Get the path to the sandbox package-db in a project
getSandboxPkgDb :: (FilePath -> [String] -> String -> IO String)
             -> FilePath
             -- ^ Cabal build platform, i.e. @buildPlatform@
             -> Version
             -- ^ GHC version (@cProjectVersion@ is your friend)
             -> IO (Maybe FilePath)
getSandboxPkgDb readProc =
    CabalHelper.Shared.Sandbox.getSandboxPkgDb $ unsafePerformIO $ buildPlatform readProc

buildPlatform :: (FilePath -> [String] -> String -> IO String) -> IO String
buildPlatform readProc = do
  exe  <- findLibexecExe
  CabalHelper.Shared.Sandbox.dropWhileEnd isSpace <$> readProc exe ["print-build-platform"] ""

-- | This exception is thrown by all 'runQuery' functions if the internal
-- wrapper executable cannot be found. You may catch this and present the user
-- an appropriate error message however the default is to print
-- 'libexecNotFoundError'.
data LibexecNotFoundError = LibexecNotFoundError String FilePath
                          deriving (Typeable)
instance Exception LibexecNotFoundError
instance Show LibexecNotFoundError where
  show (LibexecNotFoundError exe dir) =
    libexecNotFoundError exe dir "https://github.com/DanielG/cabal-helper/issues"

findLibexecExe :: IO FilePath
findLibexecExe = do
    libexecdir <- getLibexecDir
    let exeName = "cabal-helper-wrapper"
        exe = libexecdir </> exeName <.> exeExtension'

    exists <- doesFileExist exe

    if exists
       then return exe
       else do
         mdir <- tryFindCabalHelperTreeLibexecDir
         case mdir of
           Nothing ->
               error $ throw $ LibexecNotFoundError exeName libexecdir
           Just dir ->
               return $ dir </> "dist" </> "build" </> exeName </> exeName

tryFindCabalHelperTreeLibexecDir :: IO (Maybe FilePath)
tryFindCabalHelperTreeLibexecDir = do
  exe <- getExecutablePath'
  dir <- case takeFileName exe of
    "ghc" -> do -- we're probably in ghci; try CWD
        getCurrentDirectory
    _ ->
        return $ (!!4) $ iterate takeDirectory exe
  exists <- doesFileExist $ dir </> "cabal-helper.cabal"
  return $ if exists
             then Just dir
             else Nothing

libexecNotFoundError :: String   -- ^ Name of the executable we were trying to
                                 -- find
                     -> FilePath -- ^ Path to @$libexecdir@
                     -> String   -- ^ URL the user will be directed towards to
                                 -- report a bug.
                     -> String
libexecNotFoundError exe dir reportBug = printf
 ( "Could not find $libexecdir/%s\n"
 ++"\n"
 ++"If you are a cabal-helper developer you can set the environment variable\n"
 ++"`cabal_helper_libexecdir' to override $libexecdir[1]. The following will\n"
 ++"work in the cabal-helper source tree:\n"
 ++"\n"
 ++"    $ export cabal_helper_libexecdir=$PWD/dist/build/%s\n"
 ++"\n"
 ++"[1]: %s\n"
 ++"\n"
 ++"If you don't know what I'm talking about something went wrong with your\n"
 ++"installation. Please report this problem here:\n"
 ++"\n"
 ++"    %s") exe exe dir reportBug

getExecutablePath' :: IO FilePath
getExecutablePath' =
#if MIN_VERSION_base(4,6,0)
    getExecutablePath
#else
    getProgName
#endif

lookupEnv' :: String -> IO (Maybe String)
lookupEnv' k = lookup k <$> getEnvironment

exeExtension' :: FilePath
exeExtension' = Distribution.Simple.BuildPaths.exeExtension