path: root/src/Propellor/Protocol.hs
diff options
authorJoey Hess2017-06-18 18:57:41 -0400
committerJoey Hess2017-06-18 18:57:41 -0400
commit217f787df9d6474c9a57fd29b6b2fa29bef64a8a (patch)
tree08478eff44b6a4f54c8b9682a4c045c516723e0c /src/Propellor/Protocol.hs
parente32ff4337a1a7ebb9c6235cba55a8747e0429ec5 (diff)
my pipe trick didn't work; fallback to NoBuffering
Not sure what the problem was, but it hung. Also though, I noticed that stdin was still open when git fetch was run, so if git fetch itself decided to read from stdin, it would mess up the protocol forwarding. While git fetch should never read from stdin, that was reason enough to fall back to plan B.
Diffstat (limited to 'src/Propellor/Protocol.hs')
1 files changed, 7 insertions, 3 deletions
diff --git a/src/Propellor/Protocol.hs b/src/Propellor/Protocol.hs
index e90155f3..ae7e0404 100644
--- a/src/Propellor/Protocol.hs
+++ b/src/Propellor/Protocol.hs
@@ -53,7 +53,11 @@ sendMarked' h marker s = do
hFlush h
getMarked :: Handle -> Marker -> IO (Maybe String)
-getMarked h marker = go =<< catchMaybeIO (hGetLine h)
+getMarked h marker = do
+ -- Avoid buffering anything in Handle, so that the data after
+ -- the marker will be available to be read from the underlying Fd.
+ hSetBuffering stdin NoBuffering
+ go =<< catchMaybeIO (hGetLine h)
go Nothing = return Nothing
go (Just l) = case fromMarked marker l of
@@ -65,8 +69,8 @@ getMarked h marker = go =<< catchMaybeIO (hGetLine h)
debug ["received marked", marker]
return (Just v)
-req :: Stage -> Marker -> (String -> IO ()) -> IO ()
-req stage marker a = do
+reqMarked :: Stage -> Marker -> (String -> IO ()) -> IO ()
+reqMarked stage marker a = do
debug ["requested marked", marker]
sendMarked' stdout statusMarker (show stage)
maybe noop a =<< getMarked stdin marker