Merge branch 'joeyconfig'

Conflicts:
	Propellor/Property/Docker.hs

1 files changed, 18 insertions, 2 deletions

diff --git a/Propellor/CmdLine.hs b/Propellor/CmdLine.hs
index a9c61993..5ea982c3 100644
--- a/Propellor/CmdLine.hs
+++ b/Propellor/CmdLine.hs
@@ -8,9 +8,12 @@ import System.Log.Formatter
 import System.Log.Handler (setFormatter, LogHandler)
 import System.Log.Handler.Simple
 import System.PosixCompat
+import Control.Exception (bracket)
+import System.Posix.IO
 
 import Propellor
 import qualified Propellor.Property.Docker as Docker
+import qualified Propellor.Property.Docker.Shim as DockerShim
 import Utility.FileMode
 import Utility.SafeCommand
 
@@ -53,6 +56,7 @@ processCmdLine = go =<< getArgs
 
 defaultMain :: [HostName -> Maybe [Property]] -> IO ()
 defaultMain getprops = do
+	DockerShim.cleanEnv
 	checkDebugMode
 	cmdline <- processCmdLine
 	debug ["command line: ", show cmdline]
@@ -69,14 +73,26 @@ defaultMain getprops = do
 	go True cmdline = updateFirst cmdline $ go False cmdline
 	go False (Spin host) = withprops host $ const $ spin host
 	go False (Run host) = ifM ((==) 0 <$> getRealUserID)
-		( withprops host ensureProperties
+		( onlyProcess $ withprops host ensureProperties
 		, go True (Spin host)
 		)
-	go False (Boot host) = withprops host $ boot
+	go False (Boot host) = onlyProcess $ withprops host $ boot
 
 	withprops host a = maybe (unknownhost host) a $
 		headMaybe $ catMaybes $ map (\get -> get host) getprops
 
+onlyProcess :: IO a -> IO a
+onlyProcess a = bracket lock unlock (const a)
+  where
+	lock = do
+		l <- createFile lockfile stdFileMode
+		setLock l (WriteLock, AbsoluteSeek, 0, 0)
+			`catchIO` const alreadyrunning
+		return l
+	unlock = closeFd
+	alreadyrunning = error "Propellor is already running on this host!"
+	lockfile = localdir </> ".lock"
+
 unknownhost :: HostName -> IO a
 unknownhost h = errorMessage $ unlines
 	[ "Unknown host: " ++ h