gistfile1.txt

-- | throw a timeout exception to the handling thread -- it'll clean up
-- everything
timerCallback :: EvLoopPtr         -- ^ loop obj
              -> EvTimerPtr        -- ^ timer obj
              -> IORef CTime       -- ^ when to timeout?
              -> MVar ThreadId     -- ^ thread to kill
              -> TimerCallback
timerCallback loop tmr ioref tmv _ _ _ = do
    debug "Backend.timerCallback: entered"

    now       <- getCurrentDateTime
    whenToDie <- readIORef ioref

    if whenToDie < now
      then do
          debug "Backend.timerCallback: killing thread"
          tid <- readMVar tmv
          throwTo tid TimeoutException

      else do    -- re-arm the timer
          -- fixme: should set repeat here, have to wait for an hlibev patch to
          -- do it
        let newtval = fromRational . toRational $ (whenToDie - now)
        evTimerSetRepeat tmr newtval
        evTimerAgain loop tmr