diff options
Diffstat (limited to 'libraries/ghc-boot/GHC/BaseDir.hs')
-rw-r--r-- | libraries/ghc-boot/GHC/BaseDir.hs | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/libraries/ghc-boot/GHC/BaseDir.hs b/libraries/ghc-boot/GHC/BaseDir.hs index 0001837f75..c2fb3bbdae 100644 --- a/libraries/ghc-boot/GHC/BaseDir.hs +++ b/libraries/ghc-boot/GHC/BaseDir.hs @@ -12,7 +12,11 @@ -- installation location at build time. ghc-pkg also can expand those variables -- and so needs the top dir location to do that too. -module GHC.BaseDir where +module GHC.BaseDir + ( expandTopDir + , expandPathVar + , getBaseDir + ) where import Prelude -- See Note [Why do we import Prelude here?] @@ -20,11 +24,9 @@ import Data.List (stripPrefix) import Data.Maybe (listToMaybe) import System.FilePath --- Windows -#if defined(mingw32_HOST_OS) -import System.Environment (getExecutablePath) --- POSIX -#elif defined(darwin_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS) || defined(openbsd_HOST_OS) || defined(netbsd_HOST_OS) +#if MIN_VERSION_base(4,17,0) +import System.Environment (executablePath) +#else import System.Environment (getExecutablePath) #endif @@ -43,17 +45,27 @@ expandPathVar var value str expandPathVar var value (x:xs) = x : expandPathVar var value xs expandPathVar _ _ [] = [] +#if !MIN_VERSION_base(4,17,0) +-- Polyfill for base-4.17 executablePath +executablePath :: Maybe (IO (Maybe FilePath)) +executablePath = Just (Just <$> getExecutablePath) +#elif !MIN_VERSION_base(4,18,0) && defined(js_HOST_ARCH) +-- executablePath is missing from base < 4.18.0 on js_HOST_ARCH +executablePath :: Maybe (IO (Maybe FilePath)) +executablePath = Nothing +#endif + -- | Calculate the location of the base dir getBaseDir :: IO (Maybe String) #if defined(mingw32_HOST_OS) -getBaseDir = Just . (\p -> p </> "lib") . rootDir <$> getExecutablePath +getBaseDir = maybe (pure Nothing) ((((</> "lib") . rootDir) <$>) <$>) executablePath where -- locate the "base dir" when given the path -- to the real ghc executable (as opposed to symlink) -- that is running this function. rootDir :: FilePath -> FilePath rootDir = takeDirectory . takeDirectory . normalise -#elif defined(darwin_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS) || defined(openbsd_HOST_OS) || defined(netbsd_HOST_OS) +#else -- on unix, this is a bit more confusing. -- The layout right now is something like -- @@ -65,14 +77,15 @@ getBaseDir = Just . (\p -> p </> "lib") . rootDir <$> getExecutablePath -- As such, we first need to find the absolute location to the -- binary. -- --- getExecutablePath will return (3). One takeDirectory will +-- executablePath will return (3). One takeDirectory will -- give use /lib/ghc-X.Y.Z/bin, and another will give us (4). -- -- This of course only works due to the current layout. If -- the layout is changed, such that we have ghc-X.Y.Z/{bin,lib} -- this would need to be changed accordingly. -- -getBaseDir = Just . (\p -> p </> "lib") . takeDirectory . takeDirectory <$> getExecutablePath -#else -getBaseDir = return Nothing +getBaseDir = maybe (pure Nothing) ((((</> "lib") . rootDir) <$>) <$>) executablePath + where + rootDir :: FilePath -> FilePath + rootDir = takeDirectory . takeDirectory #endif |