content: -----------------------------------------------------------------------------
  -- |
  -- Module      :  Distribution.Simple
  -- Copyright   :  Isaac Jones 2003-2005
  -- License     :  BSD3
  --
  -- Maintainer  :  cabal-devel@haskell.org
  -- Portability :  portable
  --
  -- This is the command line front end to the Simple build system. When given
  -- the parsed command-line args and package information, is able to perform
  -- basic commands like configure, build, install, register, etc.
  --
  -- This module exports the main functions that Setup.hs scripts use. It
  -- re-exports the 'UserHooks' type, the standard entry points like
  -- 'defaultMain' and 'defaultMainWithHooks' and the predefined sets of
  -- 'UserHooks' that custom @Setup.hs@ scripts can extend to add their own
  -- behaviour.
  --
  -- This module isn't called \"Simple\" because it's simple.  Far from
  -- it.  It's called \"Simple\" because it does complicated things to
  -- simple software.
  --
  -- The original idea was that there could be different build systems that all
  -- presented the same compatible command line interfaces. There is still a
  -- "Distribution.Make" system but in practice no packages use it.
  
  {-
  Work around this warning:
  libraries/Cabal/Distribution/Simple.hs:78:0:
      Warning: In the use of `runTests'
               (imported from Distribution.Simple.UserHooks):
               Deprecated: "Please use the new testing interface instead!"
  -}
  {-# OPTIONS_GHC -fno-warn-deprecations #-}
  
  module Distribution.Simple (
          module Distribution.Package,
          module Distribution.Version,
          module Distribution.License,
          module Distribution.Simple.Compiler,
          module Language.Haskell.Extension,
          -- * Simple interface
          defaultMain, defaultMainNoRead, defaultMainArgs,
          -- * Customization
          UserHooks(..), Args,
          defaultMainWithHooks, defaultMainWithHooksArgs,
          -- ** Standard sets of hooks
          simpleUserHooks,
          autoconfUserHooks,
          defaultUserHooks, emptyUserHooks,
          -- ** Utils
          defaultHookedPackageDesc
    ) where
  
  -- local
  import Distribution.Simple.Compiler hiding (Flag)
  import Distribution.Simple.UserHooks
  import Distribution.Package --must not specify imports, since we're exporting module.
  import Distribution.PackageDescription
           ( PackageDescription(..), GenericPackageDescription, Executable(..)
           , updatePackageDescription, hasLibs
           , HookedBuildInfo, emptyHookedBuildInfo )
  import Distribution.PackageDescription.Parse
           ( readPackageDescription, readHookedBuildInfo )
  import Distribution.PackageDescription.Configuration
           ( flattenPackageDescription )
  import Distribution.Simple.Program
           ( defaultProgramConfiguration, addKnownPrograms, builtinPrograms
           , restoreProgramConfiguration, reconfigurePrograms )
  import Distribution.Simple.PreProcess (knownSuffixHandlers, PPSuffixHandler)
  import Distribution.Simple.Setup
  import Distribution.Simple.Command
  
  import Distribution.Simple.Build        ( build, repl )
  import Distribution.Simple.SrcDist      ( sdist )
  import Distribution.Simple.Register
           ( register, unregister )
  
  import Distribution.Simple.Configure
           ( getPersistBuildConfig, maybeGetPersistBuildConfig
           , writePersistBuildConfig, checkPersistBuildConfigOutdated
           , configure, checkForeignDeps )
  
  import Distribution.Simple.LocalBuildInfo ( LocalBuildInfo(..) )
  import Distribution.Simple.Bench (bench)
  import Distribution.Simple.BuildPaths ( srcPref)
  import Distribution.Simple.Test (test)
  import Distribution.Simple.Install (install)
  import Distribution.Simple.Haddock (haddock, hscolour)
  import Distribution.Simple.Utils
           (die, notice, info, warn, setupMessage, chattyTry,
            defaultPackageDesc, defaultHookedPackageDesc,
            rawSystemExitWithEnv, cabalVersion, topHandler )
  import Distribution.System
           ( OS(..), buildOS )
  import Distribution.Verbosity
  import Language.Haskell.Extension
  import Distribution.Version
  import Distribution.License
  import Distribution.Text
           ( display )
  
  -- Base
  import System.Environment(getArgs, getProgName)
  import System.Directory(removeFile, doesFileExist,
                          doesDirectoryExist, removeDirectoryRecursive)
  import System.Exit       (exitWith,ExitCode(..))
  import System.IO.Error   (isDoesNotExistError)
  import Control.Exception (throwIO)
  import Distribution.Compat.Environment (getEnvironment)
  import Distribution.Compat.Exception (catchIO)
  
  import Control.Monad   (when)
  import Data.List       (intercalate, unionBy, nub, (\\))
  
  -- | A simple implementation of @main@ for a Cabal setup script.
  -- It reads the package description file using IO, and performs the
  -- action specified on the command line.
  defaultMain :: IO ()
  defaultMain = getArgs >>= defaultMainHelper simpleUserHooks
  
  -- | A version of 'defaultMain' that is passed the command line
  -- arguments, rather than getting them from the environment.
  defaultMainArgs :: [String] -> IO ()
  defaultMainArgs = defaultMainHelper simpleUserHooks
  
  -- | A customizable version of 'defaultMain'.
  defaultMainWithHooks :: UserHooks -> IO ()
  defaultMainWithHooks hooks = getArgs >>= defaultMainHelper hooks
  
  -- | A customizable version of 'defaultMain' that also takes the command
  -- line arguments.
  defaultMainWithHooksArgs :: UserHooks -> [String] -> IO ()
  defaultMainWithHooksArgs = defaultMainHelper
  
  -- | Like 'defaultMain', but accepts the package description as input
  -- rather than using IO to read it.
  defaultMainNoRead :: GenericPackageDescription -> IO ()
  defaultMainNoRead pkg_descr =
    getArgs >>=
    defaultMainHelper simpleUserHooks { readDesc = return (Just pkg_descr) }
  
  defaultMainHelper :: UserHooks -> Args -> IO ()
  defaultMainHelper hooks args = topHandler $
    case commandsRun (globalCommand commands) commands args of
      CommandHelp   help                 -> printHelp help
      CommandList   opts                 -> printOptionsList opts
      CommandErrors errs                 -> printErrors errs
      CommandReadyToGo (flags, commandParse)  ->
        case commandParse of
          _ | fromFlag (globalVersion flags)        -> printVersion
            | fromFlag (globalNumericVersion flags) -> printNumericVersion
          CommandHelp     help           -> printHelp help
          CommandList     opts           -> printOptionsList opts
          CommandErrors   errs           -> printErrors errs
          CommandReadyToGo action        -> action
  
    where
      printHelp help = getProgName >>= putStr . help
      printOptionsList = putStr . unlines
      printErrors errs = do
        putStr (intercalate "\n" errs)
        exitWith (ExitFailure 1)
      printNumericVersion = putStrLn $ display cabalVersion
      printVersion        = putStrLn $ "Cabal library version "
                                    ++ display cabalVersion
  
      progs = addKnownPrograms (hookedPrograms hooks) defaultProgramConfiguration
      commands =
        [configureCommand progs `commandAddAction` \fs as ->
                                                   configureAction    hooks fs as >> return ()
        ,buildCommand     progs `commandAddAction` buildAction        hooks
        ,replCommand      progs `commandAddAction` replAction         hooks
        ,installCommand         `commandAddAction` installAction      hooks
        ,copyCommand            `commandAddAction` copyAction         hooks
        ,haddockCommand         `commandAddAction` haddockAction      hooks
        ,cleanCommand           `commandAddAction` cleanAction        hooks
        ,sdistCommand           `commandAddAction` sdistAction        hooks
        ,hscolourCommand        `commandAddAction` hscolourAction     hooks
        ,registerCommand        `commandAddAction` registerAction     hooks
        ,unregisterCommand      `commandAddAction` unregisterAction   hooks
        ,testCommand            `commandAddAction` testAction         hooks
        ,benchmarkCommand       `commandAddAction` benchAction        hooks
        ]
  
  -- | Combine the preprocessors in the given hooks with the
  -- preprocessors built into cabal.
  allSuffixHandlers :: UserHooks
                    -> [PPSuffixHandler]
  allSuffixHandlers hooks
      = overridesPP (hookedPreProcessors hooks) knownSuffixHandlers
      where
        overridesPP :: [PPSuffixHandler] -> [PPSuffixHandler] -> [PPSuffixHandler]
        overridesPP = unionBy (\x y -> fst x == fst y)
  
  configureAction :: UserHooks -> ConfigFlags -> Args -> IO LocalBuildInfo
  configureAction hooks flags args = do
                  let distPref = fromFlag $ configDistPref flags
                  pbi <- preConf hooks args flags
  
                  (mb_pd_file, pkg_descr0) <- confPkgDescr
  
                  --    get_pkg_descr (configVerbosity flags')
                  --let pkg_descr = updatePackageDescription pbi pkg_descr0
                  let epkg_descr = (pkg_descr0, pbi)
  
                  --(warns, ers) <- sanityCheckPackage pkg_descr
                  --errorOut (configVerbosity flags') warns ers
  
                  localbuildinfo0 <- confHook hooks epkg_descr flags
  
                  -- remember the .cabal filename if we know it
                  -- and all the extra command line args
                  let localbuildinfo = localbuildinfo0 {
                                         pkgDescrFile = mb_pd_file,
                                         extraConfigArgs = args
                                       }
                  writePersistBuildConfig distPref localbuildinfo
  
                  let pkg_descr = localPkgDescr localbuildinfo
                  postConf hooks args flags pkg_descr localbuildinfo
                  return localbuildinfo
                where
                  verbosity = fromFlag (configVerbosity flags)
                  confPkgDescr :: IO (Maybe FilePath, GenericPackageDescription)
                  confPkgDescr = do
                    mdescr <- readDesc hooks
                    case mdescr of
                      Just descr -> return (Nothing, descr)
                      Nothing -> do
                        pdfile <- defaultPackageDesc verbosity
                        descr  <- readPackageDescription verbosity pdfile
                        return (Just pdfile, descr)
  
  buildAction :: UserHooks -> BuildFlags -> Args -> IO ()
  buildAction hooks flags args = do
    let distPref  = fromFlag $ buildDistPref flags
        verbosity = fromFlag $ buildVerbosity flags
  
    lbi <- getBuildConfig hooks verbosity distPref
    progs <- reconfigurePrograms verbosity
               (buildProgramPaths flags)
               (buildProgramArgs flags)
               (withPrograms lbi)
  
    hookedAction preBuild buildHook postBuild
                 (return lbi { withPrograms = progs })
                 hooks flags { buildArgs = args } args
  
  replAction :: UserHooks -> ReplFlags -> Args -> IO ()
  replAction hooks flags args = do
    let distPref  = fromFlag $ replDistPref flags
        verbosity = fromFlag $ replVerbosity flags
  
    lbi <- getBuildConfig hooks verbosity distPref
    progs <- reconfigurePrograms verbosity
               (replProgramPaths flags)
               (replProgramArgs flags)
               (withPrograms lbi)
  
    pbi <- preRepl hooks args flags
    let lbi' = lbi { withPrograms = progs }
        pkg_descr0 = localPkgDescr lbi'
        pkg_descr = updatePackageDescription pbi pkg_descr0
    replHook hooks pkg_descr lbi' hooks flags args
    postRepl hooks args flags pkg_descr lbi'
  
  hscolourAction :: UserHooks -> HscolourFlags -> Args -> IO ()
  hscolourAction hooks flags args
      = do let distPref  = fromFlag $ hscolourDistPref flags
               verbosity = fromFlag $ hscolourVerbosity flags
           hookedAction preHscolour hscolourHook postHscolour
                        (getBuildConfig hooks verbosity distPref)
                        hooks flags args
  
  haddockAction :: UserHooks -> HaddockFlags -> Args -> IO ()
  haddockAction hooks flags args = do
    let distPref  = fromFlag $ haddockDistPref flags
        verbosity = fromFlag $ haddockVerbosity flags
  
    lbi <- getBuildConfig hooks verbosity distPref
    progs <- reconfigurePrograms verbosity
               (haddockProgramPaths flags)
               (haddockProgramArgs flags)
               (withPrograms lbi)
  
    hookedAction preHaddock haddockHook postHaddock
                 (return lbi { withPrograms = progs })
                 hooks flags args
  
  cleanAction :: UserHooks -> CleanFlags -> Args -> IO ()
  cleanAction hooks flags args = do
                  pbi <- preClean hooks args flags
  
                  pdfile <- defaultPackageDesc verbosity
                  ppd <- readPackageDescription verbosity pdfile
                  let pkg_descr0 = flattenPackageDescription ppd
                  -- We don't sanity check for clean as an error
                  -- here would prevent cleaning:
                  --sanityCheckHookedBuildInfo pkg_descr0 pbi
                  let pkg_descr = updatePackageDescription pbi pkg_descr0
  
                  cleanHook hooks pkg_descr () hooks flags
                  postClean hooks args flags pkg_descr ()
    where verbosity = fromFlag (cleanVerbosity flags)
  
  copyAction :: UserHooks -> CopyFlags -> Args -> IO ()
  copyAction hooks flags args
      = do let distPref  = fromFlag $ copyDistPref flags
               verbosity = fromFlag $ copyVerbosity flags
           hookedAction preCopy copyHook postCopy
                        (getBuildConfig hooks verbosity distPref)
                        hooks flags args
  
  installAction :: UserHooks -> InstallFlags -> Args -> IO ()
  installAction hooks flags args
      = do let distPref  = fromFlag $ installDistPref flags
               verbosity = fromFlag $ installVerbosity flags
           hookedAction preInst instHook postInst
                        (getBuildConfig hooks verbosity distPref)
                        hooks flags args
  
  sdistAction :: UserHooks -> SDistFlags -> Args -> IO ()
  sdistAction hooks flags args = do
                  let distPref = fromFlag $ sDistDistPref flags
                  pbi <- preSDist hooks args flags
  
                  mlbi <- maybeGetPersistBuildConfig distPref
                  pdfile <- defaultPackageDesc verbosity
                  ppd <- readPackageDescription verbosity pdfile
                  let pkg_descr0 = flattenPackageDescription ppd
                  sanityCheckHookedBuildInfo pkg_descr0 pbi
                  let pkg_descr = updatePackageDescription pbi pkg_descr0
  
                  sDistHook hooks pkg_descr mlbi hooks flags
                  postSDist hooks args flags pkg_descr mlbi
    where verbosity = fromFlag (sDistVerbosity flags)
  
  testAction :: UserHooks -> TestFlags -> Args -> IO ()
  testAction hooks flags args = do
      let distPref  = fromFlag $ testDistPref flags
          verbosity = fromFlag $ testVerbosity flags
      localBuildInfo <- getBuildConfig hooks verbosity distPref
      let pkg_descr = localPkgDescr localBuildInfo
      -- It is safe to do 'runTests' before the new test handler because the
      -- default action is a no-op and if the package uses the old test interface
      -- the new handler will find no tests.
      runTests hooks args False pkg_descr localBuildInfo
      hookedActionWithArgs preTest testHook postTest
              (getBuildConfig hooks verbosity distPref)
              hooks flags args
  
  benchAction :: UserHooks -> BenchmarkFlags -> Args -> IO ()
  benchAction hooks flags args = do
      let distPref  = fromFlag $ benchmarkDistPref flags
          verbosity = fromFlag $ benchmarkVerbosity flags
      hookedActionWithArgs preBench benchHook postBench
              (getBuildConfig hooks verbosity distPref)
              hooks flags args
  
  registerAction :: UserHooks -> RegisterFlags -> Args -> IO ()
  registerAction hooks flags args
      = do let distPref  = fromFlag $ regDistPref flags
               verbosity = fromFlag $ regVerbosity flags
           hookedAction preReg regHook postReg
                        (getBuildConfig hooks verbosity distPref)
                        hooks flags args
  
  unregisterAction :: UserHooks -> RegisterFlags -> Args -> IO ()
  unregisterAction hooks flags args
      = do let distPref  = fromFlag $ regDistPref flags
               verbosity = fromFlag $ regVerbosity flags
           hookedAction preUnreg unregHook postUnreg
                        (getBuildConfig hooks verbosity distPref)
                        hooks flags args
  
  hookedAction :: (UserHooks -> Args -> flags -> IO HookedBuildInfo)
          -> (UserHooks -> PackageDescription -> LocalBuildInfo
                        -> UserHooks -> flags -> IO ())
          -> (UserHooks -> Args -> flags -> PackageDescription
                        -> LocalBuildInfo -> IO ())
          -> IO LocalBuildInfo
          -> UserHooks -> flags -> Args -> IO ()
  hookedAction pre_hook cmd_hook =
      hookedActionWithArgs pre_hook (\h _ pd lbi uh flags -> cmd_hook h pd lbi uh flags)
  
  hookedActionWithArgs :: (UserHooks -> Args -> flags -> IO HookedBuildInfo)
          -> (UserHooks -> Args -> PackageDescription -> LocalBuildInfo
                        -> UserHooks -> flags -> IO ())
          -> (UserHooks -> Args -> flags -> PackageDescription
                        -> LocalBuildInfo -> IO ())
          -> IO LocalBuildInfo
          -> UserHooks -> flags -> Args -> IO ()
  hookedActionWithArgs pre_hook cmd_hook post_hook get_build_config hooks flags args = do
     pbi <- pre_hook hooks args flags
     localbuildinfo <- get_build_config
     let pkg_descr0 = localPkgDescr localbuildinfo
     --pkg_descr0 <- get_pkg_descr (get_verbose flags)
     sanityCheckHookedBuildInfo pkg_descr0 pbi
     let pkg_descr = updatePackageDescription pbi pkg_descr0
     -- TODO: should we write the modified package descr back to the
     -- localbuildinfo?
     cmd_hook hooks args pkg_descr localbuildinfo hooks flags
     post_hook hooks args flags pkg_descr localbuildinfo
  
  sanityCheckHookedBuildInfo :: PackageDescription -> HookedBuildInfo -> IO ()
  sanityCheckHookedBuildInfo PackageDescription { library = Nothing } (Just _,_)
      = die $ "The buildinfo contains info for a library, "
           ++ "but the package does not have a library."
  
  sanityCheckHookedBuildInfo pkg_descr (_, hookExes)
      | not (null nonExistant)
      = die $ "The buildinfo contains info for an executable called '"
           ++ head nonExistant ++ "' but the package does not have a "
           ++ "executable with that name."
    where
      pkgExeNames  = nub (map exeName (executables pkg_descr))
      hookExeNames = nub (map fst hookExes)
      nonExistant  = hookExeNames \\ pkgExeNames
  
  sanityCheckHookedBuildInfo _ _ = return ()
  
  
  getBuildConfig :: UserHooks -> Verbosity -> FilePath -> IO LocalBuildInfo
  getBuildConfig hooks verbosity distPref = do
    lbi_wo_programs <- getPersistBuildConfig distPref
    -- Restore info about unconfigured programs, since it is not serialized
    let lbi = lbi_wo_programs {
      withPrograms = restoreProgramConfiguration
                       (builtinPrograms ++ hookedPrograms hooks)
                       (withPrograms lbi_wo_programs)
    }
  
    case pkgDescrFile lbi of
      Nothing -> return lbi
      Just pkg_descr_file -> do
        outdated <- checkPersistBuildConfigOutdated distPref pkg_descr_file
        if outdated
          then reconfigure pkg_descr_file lbi
          else return lbi
  
    where
      reconfigure :: FilePath -> LocalBuildInfo -> IO LocalBuildInfo
      reconfigure pkg_descr_file lbi = do
        notice verbosity $ pkg_descr_file ++ " has been changed. "
                        ++ "Re-configuring with most recently used options. "
                        ++ "If this fails, please run configure manually.\n"
        let cFlags = configFlags lbi
        let cFlags' = cFlags {
              -- Since the list of unconfigured programs is not serialized,
              -- restore it to the same value as normally used at the beginning
              -- of a configure run:
              configPrograms = restoreProgramConfiguration
                                 (builtinPrograms ++ hookedPrograms hooks)
                                 (configPrograms cFlags),
  
              -- Use the current, not saved verbosity level:
              configVerbosity = Flag verbosity
            }
        configureAction hooks cFlags' (extraConfigArgs lbi)
  
  
  -- --------------------------------------------------------------------------
  -- Cleaning
  
  clean :: PackageDescription -> CleanFlags -> IO ()
  clean pkg_descr flags = do
      let distPref = fromFlag $ cleanDistPref flags
      notice verbosity "cleaning..."
  
      maybeConfig <- if fromFlag (cleanSaveConf flags)
                       then maybeGetPersistBuildConfig distPref
                       else return Nothing
  
      -- remove the whole dist/ directory rather than tracking exactly what files
      -- we created in there.
      chattyTry "removing dist/" $ do
        exists <- doesDirectoryExist distPref
        when exists (removeDirectoryRecursive distPref)
  
      -- Any extra files the user wants to remove
      mapM_ removeFileOrDirectory (extraTmpFiles pkg_descr)
  
      -- If the user wanted to save the config, write it back
      maybe (return ()) (writePersistBuildConfig distPref) maybeConfig
  
    where
          removeFileOrDirectory :: FilePath -> IO ()
          removeFileOrDirectory fname = do
              isDir <- doesDirectoryExist fname
              isFile <- doesFileExist fname
              if isDir then removeDirectoryRecursive fname
                else when isFile $ removeFile fname
          verbosity = fromFlag (cleanVerbosity flags)
  
  -- --------------------------------------------------------------------------
  -- Default hooks
  
  -- | Hooks that correspond to a plain instantiation of the
  -- \"simple\" build system
  simpleUserHooks :: UserHooks
  simpleUserHooks =
      emptyUserHooks {
         confHook  = configure,
         postConf  = finalChecks,
         buildHook = defaultBuildHook,
         replHook  = defaultReplHook,
         copyHook  = \desc lbi _ f -> install desc lbi f, -- has correct 'copy' behavior with params
         testHook  = defaultTestHook,
         benchHook = defaultBenchHook,
         instHook  = defaultInstallHook,
         sDistHook = \p l h f -> sdist p l f srcPref (allSuffixHandlers h),
         cleanHook = \p _ _ f -> clean p f,
         hscolourHook = \p l h f -> hscolour p l (allSuffixHandlers h) f,
         haddockHook  = \p l h f -> haddock  p l (allSuffixHandlers h) f,
         regHook   = defaultRegHook,
         unregHook = \p l _ f -> unregister p l f
        }
    where
      finalChecks _args flags pkg_descr lbi =
        checkForeignDeps pkg_descr lbi (lessVerbose verbosity)
        where
          verbosity = fromFlag (configVerbosity flags)
  
  -- | Basic autoconf 'UserHooks':
  --
  -- * 'postConf' runs @.\/configure@, if present.
  --
  -- * the pre-hooks 'preBuild', 'preClean', 'preCopy', 'preInst',
  --   'preReg' and 'preUnreg' read additional build information from
  --   /package/@.buildinfo@, if present.
  --
  -- Thus @configure@ can use local system information to generate
  -- /package/@.buildinfo@ and possibly other files.
  
  {-# DEPRECATED defaultUserHooks
       "Use simpleUserHooks or autoconfUserHooks, unless you need Cabal-1.2\n             compatibility in which case you must stick with defaultUserHooks" #-}
  defaultUserHooks :: UserHooks
  defaultUserHooks = autoconfUserHooks {
            confHook = \pkg flags -> do
                         let verbosity = fromFlag (configVerbosity flags)
                         warn verbosity
                           "defaultUserHooks in Setup script is deprecated."
                         confHook autoconfUserHooks pkg flags,
            postConf = oldCompatPostConf
      }
      -- This is the annoying old version that only runs configure if it exists.
      -- It's here for compatibility with existing Setup.hs scripts. See:
      -- https://github.com/haskell/cabal/issues/158
      where oldCompatPostConf args flags pkg_descr lbi
                = do let verbosity = fromFlag (configVerbosity flags)
                     noExtraFlags args
                     confExists <- doesFileExist "configure"
                     when confExists $
                         runConfigureScript verbosity
                           backwardsCompatHack flags lbi
  
                     pbi <- getHookedBuildInfo verbosity
                     sanityCheckHookedBuildInfo pkg_descr pbi
                     let pkg_descr' = updatePackageDescription pbi pkg_descr
                     postConf simpleUserHooks args flags pkg_descr' lbi
  
            backwardsCompatHack = True
  
  autoconfUserHooks :: UserHooks
  autoconfUserHooks
      = simpleUserHooks
        {
         postConf    = defaultPostConf,
         preBuild    = readHook buildVerbosity,
         preClean    = readHook cleanVerbosity,
         preCopy     = readHook copyVerbosity,
         preInst     = readHook installVerbosity,
         preHscolour = readHook hscolourVerbosity,
         preHaddock  = readHook haddockVerbosity,
         preReg      = readHook regVerbosity,
         preUnreg    = readHook regVerbosity
        }
      where defaultPostConf :: Args -> ConfigFlags -> PackageDescription -> LocalBuildInfo -> IO ()
            defaultPostConf args flags pkg_descr lbi
                = do let verbosity = fromFlag (configVerbosity flags)
                     noExtraFlags args
                     confExists <- doesFileExist "configure"
                     if confExists
                       then runConfigureScript verbosity
                              backwardsCompatHack flags lbi
                       else die "configure script not found."
  
                     pbi <- getHookedBuildInfo verbosity
                     sanityCheckHookedBuildInfo pkg_descr pbi
                     let pkg_descr' = updatePackageDescription pbi pkg_descr
                     postConf simpleUserHooks args flags pkg_descr' lbi
  
            backwardsCompatHack = False
  
            readHook :: (a -> Flag Verbosity) -> Args -> a -> IO HookedBuildInfo
            readHook get_verbosity a flags = do
                noExtraFlags a
                getHookedBuildInfo verbosity
              where
                verbosity = fromFlag (get_verbosity flags)
  
  runConfigureScript :: Verbosity -> Bool -> ConfigFlags -> LocalBuildInfo
                     -> IO ()
  runConfigureScript verbosity backwardsCompatHack flags lbi = do
  
    env <- getEnvironment
    let programConfig = withPrograms lbi
    (ccProg, ccFlags) <- configureCCompiler verbosity programConfig
    -- The C compiler's compilation and linker flags (e.g.
    -- "C compiler flags" and "Gcc Linker flags" from GHC) have already
    -- been merged into ccFlags, so we set both CFLAGS and LDFLAGS
    -- to ccFlags
    -- We don't try and tell configure which ld to use, as we don't have
    -- a way to pass its flags too
    let env' = appendToEnvironment ("CFLAGS",  unwords ccFlags)
               env
        args' = args ++ ["--with-gcc=" ++ ccProg]
    handleNoWindowsSH $
      rawSystemExitWithEnv verbosity "sh" args' env'
  
    where
      args = "./configure" : configureArgs backwardsCompatHack flags
  
      appendToEnvironment (key, val) [] = [(key, val)]
      appendToEnvironment (key, val) (kv@(k, v) : rest)
       | key == k  = (key, v ++ " " ++ val) : rest
       | otherwise = kv : appendToEnvironment (key, val) rest
  
      handleNoWindowsSH action
        | buildOS /= Windows
        = action
  
        | otherwise
        = action
            `catchIO` \ioe -> if isDoesNotExistError ioe
                                then die notFoundMsg
                                else throwIO ioe
  
      notFoundMsg = "The package has a './configure' script. This requires a "
                 ++ "Unix compatibility toolchain such as MinGW+MSYS or Cygwin."
  
  getHookedBuildInfo :: Verbosity -> IO HookedBuildInfo
  getHookedBuildInfo verbosity = do
    maybe_infoFile <- defaultHookedPackageDesc
    case maybe_infoFile of
      Nothing       -> return emptyHookedBuildInfo
      Just infoFile -> do
        info verbosity $ "Reading parameters from " ++ infoFile
        readHookedBuildInfo verbosity infoFile
  
  defaultTestHook :: Args -> PackageDescription -> LocalBuildInfo
                  -> UserHooks -> TestFlags -> IO ()
  defaultTestHook args pkg_descr localbuildinfo _ flags =
      test args pkg_descr localbuildinfo flags
  
  defaultBenchHook :: Args -> PackageDescription -> LocalBuildInfo
                   -> UserHooks -> BenchmarkFlags -> IO ()
  defaultBenchHook args pkg_descr localbuildinfo _ flags =
      bench args pkg_descr localbuildinfo flags
  
  defaultInstallHook :: PackageDescription -> LocalBuildInfo
                     -> UserHooks -> InstallFlags -> IO ()
  defaultInstallHook pkg_descr localbuildinfo _ flags = do
    let copyFlags = defaultCopyFlags {
                        copyDistPref   = installDistPref flags,
                        copyDest       = toFlag NoCopyDest,
                        copyVerbosity  = installVerbosity flags
                    }
    install pkg_descr localbuildinfo copyFlags
    let registerFlags = defaultRegisterFlags {
                            regDistPref  = installDistPref flags,
                            regInPlace   = installInPlace flags,
                            regPackageDB = installPackageDB flags,
                            regVerbosity = installVerbosity flags
                        }
    when (hasLibs pkg_descr) $ register pkg_descr localbuildinfo registerFlags
  
  defaultBuildHook :: PackageDescription -> LocalBuildInfo
          -> UserHooks -> BuildFlags -> IO ()
  defaultBuildHook pkg_descr localbuildinfo hooks flags =
    build pkg_descr localbuildinfo flags (allSuffixHandlers hooks)
  
  defaultReplHook :: PackageDescription -> LocalBuildInfo
          -> UserHooks -> ReplFlags -> [String] -> IO ()
  defaultReplHook pkg_descr localbuildinfo hooks flags args =
    repl pkg_descr localbuildinfo flags (allSuffixHandlers hooks) args
  
  defaultRegHook :: PackageDescription -> LocalBuildInfo
          -> UserHooks -> RegisterFlags -> IO ()
  defaultRegHook pkg_descr localbuildinfo _ flags =
      if hasLibs pkg_descr
      then register pkg_descr localbuildinfo flags
      else setupMessage verbosity
             "Package contains no library to register:" (packageId pkg_descr)
    where verbosity = fromFlag (regVerbosity flags)
  