From e73e5b26aa50d41c2f6e226982446c0e883deef3 Mon Sep 17 00:00:00 2001
From: Sharif Olorin <sio@tesser.org>
Date: Wed, 28 Dec 2016 01:17:41 +0000
Subject: [PATCH] Add Sodium monad

---
 ambiata-tinfoil.cabal          |  1 +
 src/Tinfoil/Internal/Sodium.hs | 28 ++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 src/Tinfoil/Internal/Sodium.hs

diff --git a/ambiata-tinfoil.cabal b/ambiata-tinfoil.cabal
index 4df766f..432f4ac 100644
--- a/ambiata-tinfoil.cabal
+++ b/ambiata-tinfoil.cabal
@@ -50,6 +50,7 @@ library
                        Tinfoil.Data.Verify
                        Tinfoil.Encode
                        Tinfoil.Hash
+                       Tinfoil.Internal.Sodium
                        Tinfoil.Internal.Sodium.Data
                        Tinfoil.Internal.Sodium.Foreign
                        Tinfoil.KDF
diff --git a/src/Tinfoil/Internal/Sodium.hs b/src/Tinfoil/Internal/Sodium.hs
new file mode 100644
index 0000000..3bbf51c
--- /dev/null
+++ b/src/Tinfoil/Internal/Sodium.hs
@@ -0,0 +1,28 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+
+module Tinfoil.Internal.Sodium (
+    Sodium(..)
+  , runSodium
+  ) where
+
+import           P
+
+import           System.IO (IO)
+
+import           Tinfoil.Internal.Sodium.Data
+import           Tinfoil.Internal.Sodium.Foreign
+
+newtype Sodium a =
+    Sodium (IO a)
+  deriving (Monad, Functor, Applicative)
+
+runSodium :: Sodium a -> IO (Maybe' a)
+runSodium (Sodium s) =
+  sodiumInit >>= \x -> case x of
+    SodiumInitialised ->
+      Just' <$> s
+    SodiumNotInitialised ->
+      pure Nothing'