still can't express custom-setup deps

They need unix on non-windows, for Utility.Env, which Build.Configure uses,
but cabal can't express that in a custom-setup stanza.

To avoid this problem, Utility.Env would need to be moved into
unix-compat..

1 files changed, 24 insertions, 0 deletions

diff --git a/Utility/Env.hs b/Utility/Env.hs
index dfebd9868..c56f4ec23 100644
--- a/Utility/Env.hs
+++ b/Utility/Env.hs
@@ -16,6 +16,7 @@ import Control.Applicative
 import Data.Maybe
 import Prelude
 import qualified System.Environment as E
+import qualified System.SetEnv
 #else
 import qualified System.Posix.Env as PE
 #endif
@@ -41,6 +42,29 @@ getEnvironment = PE.getEnvironment
 getEnvironment = E.getEnvironment
 #endif
 
+{- Sets an environment variable. To overwrite an existing variable,
+ - overwrite must be True.
+ -
+ - On Windows, setting a variable to "" unsets it. -}
+setEnv :: String -> String -> Bool -> IO ()
+#ifndef mingw32_HOST_OS
+setEnv var val overwrite = PE.setEnv var val overwrite
+#else
+setEnv var val True = System.SetEnv.setEnv var val
+setEnv var val False = do
+	r <- getEnv var
+	case r of
+		Nothing -> setEnv var val True
+		Just _ -> return ()
+#endif
+
+unsetEnv :: String -> IO ()
+#ifndef mingw32_HOST_OS
+unsetEnv = PE.unsetEnv
+#else
+unsetEnv = System.SetEnv.unsetEnv
+#endif
+
 {- Adds the environment variable to the input environment. If already
  - present in the list, removes the old value.
  -