{-# LANGUAGE CPP #-}

{- |

Module : ./Common/Timing.hs

Description : utility module for measuring execution time

Copyright : (c) C. Maeder DFKI GmbH

License : GPLv2 or higher, see LICENSE.txt

Maintainer : Christian.Maeder@dfki.de

Stability : provisional

Portability : portable

Utility functions that can't be found in the libraries

but should be shared across Hets.

-}

module Common.Timing where

#ifdef UNIX

import System.Posix.Time

import System.Posix.Types

#else

import Data.Time.Clock

#endif

import Data.Fixed

import Data.Time

import Control.Monad

import Numeric

newtype HetsTime = HetsTime

#ifdef UNIX

EpochTime

#else

UTCTime

#endif

getHetsTime :: IO HetsTime

getHetsTime = liftM HetsTime

#ifdef UNIX

epochTime

#else

getCurrentTime

#endif

measureWallTime :: IO a -> IO (a, TimeOfDay)

measureWallTime f = do

startTime <- getHetsTime

result <- f

endTime <- getHetsTime

let wallTimeUsed = diffHetsTime endTime startTime

return (result, wallTimeUsed)

diffHetsTime :: HetsTime -> HetsTime -> TimeOfDay

diffHetsTime (HetsTime t1) (HetsTime t2) =

timeToTimeOfDay $ secondsToDiffTime $ round

(realToFrac (

#ifdef UNIX

(-)

#else

diffUTCTime

#endif

t1 t2) :: Double)

timeOfDayToSeconds :: TimeOfDay -> Int

timeOfDayToSeconds TimeOfDay { todHour = hours

, todMin = minutes

, todSec = seconds

} =

(floor . toDouble) seconds + 60 * (minutes + 60 * hours)

where

toDouble :: Pico -> Double

toDouble s = case readSigned readFloat $ show s of

[(x, "")] -> x

_ -> error $ "timeOfDayToSeconds: Failed reading the number " ++ show s