Bug fix: don't get confused by align separators in input (issue 14)

This solves the common case of a template separator character (such as
{) popping up in xmobar's input (e.g., inside a window title) and
confusing the parser.

4 files changed, 34 insertions, 18 deletions

diff --git a/NEWS b/NEWS
index 839c0dc..6d5ecd2 100644
--- a/NEWS
+++ b/NEWS
@@ -17,12 +17,16 @@ _Bug fixes_
 
   - Text is now correctly centered vertically.
   - `FullBM` border spec fixed.
+  - [issue 14]: `StdinReader` and other plugins accepting external
+    input don't get confused anymore when characters from `alignSep`
+    appear in their input.
   - [issue 27]: `BottomSize` placement now respects its width argument.
   - [issue 28]: Compilation in Mac OS X fixed.
   - [issue 30]: `Mail` plugin can be specified anywhere in commands list.
   - [issue 36]: Battery monitor now supports non-standard locations of
     the `/sys/class/power_supply/AC/online` file.
 
+[issue 14]: http://code.google.com/p/xmobar/issues/detail?id=14
 [issue 27]: http://code.google.com/p/xmobar/issues/detail?id=27
 [issue 28]: http://code.google.com/p/xmobar/issues/detail?id=28
 [issue 30]: http://code.google.com/p/xmobar/issues/detail?id=30
diff --git a/src/Main.hs b/src/Main.hs
index aad87e7..c069b8e 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -60,11 +60,26 @@ main = do
   doOpts civ o
   conf  <- readIORef civ
   fs    <- initFont d (font conf)
-  cl    <- parseTemplate conf (template conf)
-  vars  <- mapM startCommand cl
+  cls   <- mapM (parseTemplate conf) (splitTemplate conf)
+  vars  <- mapM (mapM startCommand) cls
   (r,w) <- createWin d fs conf
   eventLoop (XConf d r w fs conf) vars
 
+-- | Splits the template in its parts
+splitTemplate :: Config -> [String]
+splitTemplate conf =
+  case break (==l) t of
+    (le,_:re) -> case break (==r) re of
+                   (ce,_:ri) -> [le, ce, ri]
+                   _         -> def
+    _         -> def
+  where [l, r] = if length (alignSep conf) == 2
+                 then alignSep conf
+                 else alignSep defaultConfig
+        t = template conf
+        def = [t, "", ""]
+
+
 -- | Reads the configuration files or quits with an error
 readConfig :: FilePath -> IO (Config,[String])
 readConfig f = do
diff --git a/src/Plugins/StdinReader.hs b/src/Plugins/StdinReader.hs
index 2ee217e..935d76a 100644
--- a/src/Plugins/StdinReader.hs
+++ b/src/Plugins/StdinReader.hs
@@ -26,7 +26,8 @@ data StdinReader = StdinReader
 
 instance Exec StdinReader where
     start StdinReader cb = do
-        cb =<< catch (hGetLineSafe stdin) (\(SomeException e) -> do hPrint stderr e; return "")
+        cb =<< catch (hGetLineSafe stdin)
+                     (\(SomeException e) -> do hPrint stderr e; return "")
         eof <- hIsEOF stdin
         if eof
             then exitImmediately ExitSuccess
diff --git a/src/Xmobar.hs b/src/Xmobar.hs
index f3e0907..566f8e8 100644
--- a/src/Xmobar.hs
+++ b/src/Xmobar.hs
@@ -73,23 +73,27 @@ data WakeUp = WakeUp deriving (Show,Typeable)
 instance Exception WakeUp
 
 -- | The event loop
-eventLoop :: XConf -> [(Maybe ThreadId, TVar String)] -> IO ()
+eventLoop :: XConf -> [[(Maybe ThreadId, TVar String)]] -> IO ()
 eventLoop xc@(XConf d _ w fs c) v = block $ do
     tv <- atomically $ newTVar []
     t  <- myThreadId
-    ct <- forkIO (checker t tv "" `catch` \(SomeException _) -> return ())
+    ct <- forkIO (checker t tv [] `catch` \(SomeException _) -> return ())
     go tv ct
  where
     -- interrupt the drawing thread every time a var is updated
     checker t tvar ov = do
       nval <- atomically $ do
-              nv <- fmap concat $ mapM (readTVar . snd) v
+              nv <- mapM concatV v
               guard (nv /= ov)
               writeTVar tvar nv
               return nv
       throwTo t WakeUp
       checker t tvar nval
 
+    concatV xs = do
+      s <- mapM (readTVar . snd) xs
+      return $ concat s
+
     -- Continuously wait for a timer interrupt or an expose event
     go tv ct = do
       catch (unblock $ allocaXEvent $ \e ->
@@ -217,21 +221,13 @@ getStaticStrutValues (Static cx cy cw ch) rwh
           xe = xs + cw
 getStaticStrutValues _ _ = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
 
-updateWin :: TVar String -> X ()
+updateWin :: TVar [String] -> X ()
 updateWin v = do
   xc <- ask
+  s <- io $ atomically $ readTVar v
   let (conf,rec) = (config &&& rect) xc
-      [lc,rc]    = if length (alignSep conf) == 2
-                   then alignSep conf
-                   else alignSep defaultConfig
-  i <- io $ atomically $ readTVar v
-  let def     = [i,[],[]]
-      [l,c,r] = case break (==lc) i of
-                  (le,_:re) -> case break (==rc) re of
-                                 (ce,_:ri) -> [le,ce,ri]
-                                 _         -> def
-                  _         -> def
-  ps <- io $ mapM (parseString conf) [l,c,r]
+      l:c:r:_ = s ++ repeat ""
+  ps <- io $ mapM (parseString conf) [l, c, r]
   drawInWin rec ps
 
 -- $print