Clean up a bunch of code and comments.

[dead/halcyon.git] / src / OptionalConfiguration.hs

diff --git a/src/OptionalConfiguration.hs b/src/OptionalConfiguration.hs
index 0b5fd0a6b05cc0cd6ba5ee63a6cb3a5c342f0405..8fd9f6c68319d204a94efc4e3a9d17f052124758 100644 (file)
--- a/src/OptionalConfiguration.hs
+++ b/src/OptionalConfiguration.hs
@@ -11,18 +11,25 @@
 
 module OptionalConfiguration (
   OptionalCfg(..),
-  from_rc
-  )
+  from_rc )
 where
 
-import qualified Data.Configurator as DC
+import qualified Data.Configurator as DC (
+  Worth (Optional),
+  load,
+  lookup )
 
-import Data.Data (Data)
-import Data.Maybe (fromMaybe)
-import Data.Monoid (Monoid(..))
-import Data.Typeable (Typeable)
+import Data.Data ( Data )
+import Data.Maybe ( fromMaybe )
+import Data.Monoid ( Monoid(..) )
+import Data.Typeable ( Typeable )
+import Paths_halcyon ( getSysconfDir )
+import System.Directory ( getHomeDirectory )
+import System.FilePath ( (</>) )
+import System.IO ( hPutStrLn, stderr )
+import System.IO.Error ( catchIOError )
 
-import Usernames
+import Usernames ( Usernames(..) )
 
 
 -- | The same as Cfg, except everything is optional. It's easy to
@@ -87,9 +94,29 @@ instance Monoid OptionalCfg where
                     then cfg1
                     else cfg2
 
+
+-- | Obtain an 'OptionalCfg' from halcyonrc in either the global
+--   configuration directory or the user's home directory. The one in
+--   $HOME is prefixed by a dot so that it is hidden.
+--
+--   We make an attempt at cross-platform compatibility; we will try
+--   to find the correct directory even on Windows. But if the calls
+--   to getHomeDirectory/getSysconfDir fail for whatever reason, we
+--   fall back to using the Unix-specific /etc and $HOME.
+--
 from_rc :: IO OptionalCfg
 from_rc = do
-  cfg <- DC.load [ DC.Optional "$(HOME)/.halcyonrc" ]
+  etc  <- catchIOError getSysconfDir (\e -> do
+                                        hPutStrLn stderr (show e)
+                                        return "/etc")
+  home <- catchIOError getHomeDirectory (\e -> do
+                                           hPutStrLn stderr (show e)
+                                           return "$(HOME)")
+  let global_config_path = etc </> "halcyonrc"
+  let user_config_path = home </> ".halcyonrc"
+  cfg <- DC.load [ DC.Optional global_config_path,
+                   DC.Optional user_config_path ]
+
   cfg_consumer_key <- DC.lookup cfg "consumer-key"
   cfg_consumer_secret <- DC.lookup cfg "consumer-secret"
   cfg_access_token <- DC.lookup cfg "access-token"