diff options
Diffstat (limited to 'src/Xmobar')
| -rw-r--r-- | src/Xmobar/Plugins/StdinReader.hs | 42 | ||||
| -rw-r--r-- | src/Xmobar/System/Utils.hs | 11 |
2 files changed, 25 insertions, 28 deletions
diff --git a/src/Xmobar/Plugins/StdinReader.hs b/src/Xmobar/Plugins/StdinReader.hs index a29c1ad..4d5c438 100644 --- a/src/Xmobar/Plugins/StdinReader.hs +++ b/src/Xmobar/Plugins/StdinReader.hs @@ -1,3 +1,5 @@ +{-# LANGUAGE ViewPatterns #-} + ----------------------------------------------------------------------------- -- | -- Module : Plugins.StdinReader @@ -22,30 +24,36 @@ import Prelude import System.Posix.Process import System.Exit import System.IO +import System.IO.Error (isEOFError) import Xmobar.Run.Exec import Xmobar.X11.Actions (stripActions) -import Xmobar.System.Utils (onSomeException) -import Control.Monad (when) +import Control.Concurrent (threadDelay) +import Control.Exception +import Control.Monad (forever) data StdinReader = StdinReader | UnsafeStdinReader deriving (Read, Show) instance Exec StdinReader where - start stdinReader cb = do - -- The EOF check is necessary for certain systems - -- More details here https://github.com/jaor/xmobar/issues/442 - eof <- isEOF - when eof $ - do hPrint stderr "xmobar: eof at an early stage" - exitImmediately ExitSuccess - s <- - getLine `onSomeException` - (\e -> do - let errorMessage = "xmobar: Received exception " <> show e - hPrint stderr errorMessage - cb errorMessage) - cb $ escape stdinReader s - start stdinReader cb + start stdinReader cb = forever $ (cb . escape stdinReader =<< getLine) `catch` handler + where + -- rethrow async exceptions like ThreadKilled, etc. + handler (fromException -> Just e) = throwIO (e :: SomeAsyncException) + -- XMonad.Hooks.DynamicLog.statusBar starts new xmobar on every xmonad + -- reload and the old xmobar is only signalled to exit via the pipe + -- being closed, so we must unconditionally terminate on EOF, otherwise + -- there'd be a pileup of xmobars + handler (fromException -> Just e) | isEOFError e = exitImmediately ExitSuccess + -- any other exception, like "invalid argument (invalid byte sequence)", + -- is logged to both stderr and the bar itself, throttled to avoid + -- excessive CPU usage whenever someone pipes garbage into xmobar, and + -- then discarded without terminating, so a single charset error doesn't + -- break the entire xmobar + handler e = do + let errorMessage = "xmobar: Received exception " <> show e + hPutStrLn stderr errorMessage + cb $ stripActions errorMessage + threadDelay 1000000 escape :: StdinReader -> String -> String escape StdinReader = stripActions diff --git a/src/Xmobar/System/Utils.hs b/src/Xmobar/System/Utils.hs index 53052ea..24c655e 100644 --- a/src/Xmobar/System/Utils.hs +++ b/src/Xmobar/System/Utils.hs @@ -20,7 +20,6 @@ module Xmobar.System.Utils ( expandHome , changeLoop - , onSomeException , safeIndex ) where @@ -31,7 +30,6 @@ import Data.Maybe (fromMaybe) import System.Environment import System.FilePath -import Control.Exception expandHome :: FilePath -> IO FilePath expandHome ('~':'/':path) = fmap (</> path) (getEnv "HOME") @@ -47,15 +45,6 @@ changeLoop s f = atomically s >>= go guard (new /= old) return new) --- | Like 'finally', but only performs the final action if there was an --- exception raised by the computation. --- --- Note that this implementation is a slight modification of --- onException function. -onSomeException :: IO a -> (SomeException -> IO b) -> IO a -onSomeException io what = io `catch` \e -> do _ <- what e - throwIO (e :: SomeException) - (!!?) :: [a] -> Int -> Maybe a (!!?) xs i | i < 0 = Nothing |