DBusのサンプル

Counter.hs

{-# LANGUAGE OverloadedStrings #-}

module Main where

import Control.Concurrent
import Control.Monad (forever, when)
import Data.IORef
import Data.Int
import Data.ByteString.Char8
import System.Exit

import DBus
import DBus.Client

incCounter :: IORef Int -> IO Int32
incCounter counterRef = do
    y <- atomicModifyIORef counterRef (\x -> (x+1, x+1))
    return $ fromIntegral y

hello :: IORef Int -> IO ByteString
hello counterRef = do
    x <- readIORef counterRef
    return $ pack ("hello" ++ show x)

incThread :: IORef Int -> IO ()
incThread counterRef = forever $ do
    atomicModifyIORef counterRef (\x -> (x+1, x+1))
    threadDelay (1000000)

isEven :: IORef Int -> IO Bool
isEven counterRef = readIORef counterRef >>= return . even

echo :: IORef Int -> String -> IO String
echo counterRef input = do
    x <- readIORef counterRef
    return $ input ++ " " ++ show x

main :: IO ()
main = do
    counterRef <- newIORef (0 :: Int)
    client <- connectSession
    requestResult <- requestName client "com.worksap.ccms" []
    when (requestResult /= NamePrimaryOwner) $ do
        -- putStrLn "Another service owns the \"com.worksap.ccms\" bus name"                                                                                                                                       
        exitFailure

    forkIO $ incThread counterRef

    export client "/com/worksap/ccms/counter"
               [ autoMethod "com.worksap.ccms.counter" "Increment" (incCounter counterRef)
               , autoMethod "com.worksap.ccms.counter" "Hello" (hello counterRef)
               , autoMethod "com.worksap.ccms.counter" "IsEven" (isEven counterRef)
               , autoMethod "com.worksap.ccms.counter" "Echo" (echo counterRef)
               ]

    forever $ threadDelay 50000

    return ()

dbus-send --session --dest=com.worksap.ccms --print-reply /com/worksap/ccms/counter com.worksap.ccms.counter.Hello

dbus-send --session --dest=com.worksap.ccms --print-reply /com/worksap/ccms/counter com.worksap.ccms.counter.Echo string:hohogege