[PATCH master 7/7] Add support for GANETI_ROOTDIR in Haskell code

[Michael Hanselmann]

unsafePerformIO is required to go from the IO monad to pure code.

Signed-off-by: Michael Hanselmann <han...@google.com>
---
 htools/Ganeti/Path.hs |   26 ++++++++++++++------------
 1 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/htools/Ganeti/Path.hs b/htools/Ganeti/Path.hs
index 5f439dd..2446f52 100644
--- a/htools/Ganeti/Path.hs
+++ b/htools/Ganeti/Path.hs
@@ -23,31 +23,33 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 
MA
 
 -}
 
-module Ganeti.Path
-  ( defaultLuxiSocket
-  , defaultQuerySocket
-  , dataDir
-  , logDir
-  , runDir
-  , confdHmacKey
-  , clusterConfFile
-  ) where
+module Ganeti.Path where
 
 import qualified Ganeti.Constants as C
 import System.FilePath
+import System.Posix.Env (getEnv)
+import System.IO.Unsafe
 
 
+-- | Prefixes a path with the current root directory
+addNodePrefix :: FilePath -> FilePath
+addNodePrefix path = do
+  let val = unsafePerformIO $ getEnv "GANETI_ROOTDIR"
+  case val of
+    Just rootdir -> rootdir ++ path
+    Nothing -> path
+
 -- | Directory for data
 dataDir :: FilePath
-dataDir = C.autoconfLocalstatedir </> "lib" </> "ganeti"
+dataDir = addNodePrefix $ C.autoconfLocalstatedir </> "lib" </> "ganeti"
 
 -- | Directory for runtime files
 runDir :: FilePath
-runDir = C.autoconfLocalstatedir </> "run" </> "ganeti"
+runDir = addNodePrefix $ C.autoconfLocalstatedir </> "run" </> "ganeti"
 
 -- | Directory for log files
 logDir :: FilePath
-logDir = C.autoconfLocalstatedir </> "log" </> "ganeti"
+logDir = addNodePrefix $ C.autoconfLocalstatedir </> "log" </> "ganeti"
 
 -- | Directory for Unix sockets
 socketDir :: FilePath
-- 
1.7.6