From d7aeb5f545bf41d4d735afd9dd070501f540f61e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=96mer=20Sinan=20A=C4=9Facan?= <omeragacan@gmail.com>
Date: Thu, 30 Nov 2017 10:30:29 +0300
Subject: [PATCH] withDev: Close the FD on exception

---
 Crypto/Random/Entropy/Unix.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Crypto/Random/Entropy/Unix.hs b/Crypto/Random/Entropy/Unix.hs
index 9a7400c..a8aae43 100644
--- a/Crypto/Random/Entropy/Unix.hs
+++ b/Crypto/Random/Entropy/Unix.hs
@@ -58,7 +58,7 @@ withDev :: String -> (H -> IO a) -> IO a
 withDev filepath f = openDev filepath >>= \h ->
     case h of
         Nothing -> error ("device " ++ filepath ++ " cannot be grabbed")
-        Just fd -> f fd >>= \r -> (closeDev fd >> return r)
+        Just fd -> f fd `E.finally` closeDev fd
 
 closeDev :: H -> IO ()
 closeDev h = hClose h