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authorPavan Rikhi <pavan.rikhi@gmail.com>2018-03-17 22:48:24 -0400
committerjao <jao@gnu.org>2018-11-21 21:41:35 +0000
commit4d1402a1a7d87767267d48a77998e4fb13395b31 (patch)
tree17fd6160dc1fa9c8a0676a94bcf8d19b551c655c /src/Xmobar/Plugins/PipeReader.hs
parent9e2a5c7daddf683d4be7c318aefed3da3ea7a89a (diff)
downloadxmobar-4d1402a1a7d87767267d48a77998e4fb13395b31.tar.gz
xmobar-4d1402a1a7d87767267d48a77998e4fb13395b31.tar.bz2
Split Modules into Library & Executable Structure
Move the Main module to a new `app` directory. All other modules have been nested under the `Xmobar` name. Lots of module headers & imports were updated.
Diffstat (limited to 'src/Xmobar/Plugins/PipeReader.hs')
-rw-r--r--src/Xmobar/Plugins/PipeReader.hs47
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diff --git a/src/Xmobar/Plugins/PipeReader.hs b/src/Xmobar/Plugins/PipeReader.hs
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+-----------------------------------------------------------------------------
+-- |
+-- Module : Plugins.PipeReader
+-- Copyright : (c) Andrea Rossato
+-- License : BSD-style (see LICENSE)
+--
+-- Maintainer : Jose A. Ortega Ruiz <jao@gnu.org>
+-- Stability : unstable
+-- Portability : unportable
+--
+-- A plugin for reading from named pipes
+--
+-----------------------------------------------------------------------------
+
+module Xmobar.Plugins.PipeReader where
+
+import System.IO
+import Xmobar.Plugins
+import Xmobar.Environment
+import System.Posix.Files
+import Control.Concurrent(threadDelay)
+import Control.Exception
+import Control.Monad(forever, unless)
+import Control.Applicative ((<$>))
+
+data PipeReader = PipeReader String String
+ deriving (Read, Show)
+
+instance Exec PipeReader where
+ alias (PipeReader _ a) = a
+ start (PipeReader p _) cb = do
+ (def, pipe) <- split ':' <$> expandEnv p
+ unless (null def) (cb def)
+ checkPipe pipe
+ h <- openFile pipe ReadWriteMode
+ forever (hGetLineSafe h >>= cb)
+ where
+ split c xs | c `elem` xs = let (pre, post) = span (c /=) xs
+ in (pre, dropWhile (c ==) post)
+ | otherwise = ([], xs)
+
+checkPipe :: FilePath -> IO ()
+checkPipe file =
+ handle (\(SomeException _) -> waitForPipe) $ do
+ status <- getFileStatus file
+ unless (isNamedPipe status) waitForPipe
+ where waitForPipe = threadDelay 1000000 >> checkPipe file