merge from git-annex and relicense accordingly

Merge git library and utility from git-annex. The former is now relicensed
AGPL, so git-repair as a whole becomes AGPL.

For simplicity, I am relicensing the remainder of the code in git-repair
AGPL as well, per the header changes in this commit. While that code is
also technically available under the GPL license, as it's been released
under that license before, changes going forward will be only released by
me under the AGPL.

2 files changed, 68 insertions, 0 deletions

diff --git a/Utility/Env/Basic.hs b/Utility/Env/Basic.hs
new file mode 100644
index 0000000..db73827
--- /dev/null
+++ b/Utility/Env/Basic.hs
@@ -0,0 +1,25 @@
+{- portable environment variables, without any dependencies
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - License: BSD-2-clause
+ -}
+
+{-# OPTIONS_GHC -fno-warn-tabs #-}
+
+module Utility.Env.Basic (
+	getEnv,
+	getEnvDefault,
+) where
+
+import Utility.Exception
+import Control.Applicative
+import Data.Maybe
+import Prelude
+import qualified System.Environment as E
+
+getEnv :: String -> IO (Maybe String)
+getEnv = catchMaybeIO . E.getEnv
+
+getEnvDefault :: String -> String -> IO String
+getEnvDefault var fallback = fromMaybe fallback <$> getEnv var
diff --git a/Utility/Env/Set.hs b/Utility/Env/Set.hs
new file mode 100644
index 0000000..f14674c
--- /dev/null
+++ b/Utility/Env/Set.hs
@@ -0,0 +1,43 @@
+{- portable environment variables
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - License: BSD-2-clause
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Utility.Env.Set (
+	setEnv,
+	unsetEnv,
+) where
+
+#ifdef mingw32_HOST_OS
+import qualified System.SetEnv
+import Utility.Env
+#else
+import qualified System.Posix.Env as PE
+#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