From: Joey Hess <joeyh@joeyh.name>
Date: Tue, 27 Dec 2016 20:26:26 +0000 (-0400)
Subject: avoid leaving MVar empty
X-Git-Tag: archive/raspbian/10.20250416-2+rpi1~1^2~278^2~26^2~8
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=41d956e0a0c785ece59b9047610419d5a4f99e9d;p=git-annex.git

avoid leaving MVar empty

Something might want to observe the code multiple times.
---

diff --git a/Utility/MagicWormhole.hs b/Utility/MagicWormhole.hs
index e217dcdca6..3743f352ce 100644
--- a/Utility/MagicWormhole.hs
+++ b/Utility/MagicWormhole.hs
@@ -78,7 +78,7 @@ mkCodeProducer :: IO CodeProducer
 mkCodeProducer = CodeProducer <$> newEmptyMVar
 
 waitCode :: CodeObserver -> IO Code
-waitCode (CodeObserver o) = takeMVar o
+waitCode (CodeObserver o) = readMVar o
 
 sendCode :: CodeProducer -> Code -> IO ()
 sendCode (CodeProducer p) = putMVar p
@@ -119,7 +119,7 @@ sendFile f (CodeObserver observer) ps = do
 -- read from the CodeProducer, and fed to wormhole on stdin.
 receiveFile :: FilePath -> CodeProducer -> WormHoleParams -> IO Bool
 receiveFile f (CodeProducer producer) ps = runWormHoleProcess p $ \hin _hout -> do
-	Code c <- takeMVar producer
+	Code c <- readMVar producer
 	hPutStrLn hin c
 	hFlush hin
 	return True