diff options
Diffstat (limited to 'Utility')
| -rw-r--r-- | Utility/Metered.hs | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/Utility/Metered.hs b/Utility/Metered.hs index 626aa2ca1..a5dda5413 100644 --- a/Utility/Metered.hs +++ b/Utility/Metered.hs @@ -171,22 +171,27 @@ defaultChunkSize = 32 * k - chunkOverhead k = 1024 chunkOverhead = 2 * sizeOf (1 :: Int) -- GHC specific -{- Runs an action, watching a file as it grows and updating the meter. -} +{- Runs an action, watching a file as it grows and updating the meter. + - + - The file may already exist, and the action could throw the original file + - away and start over. To avoid reporting the original file size followed + - by a smaller size in that case, wait until the file starts growing + - before updating the meter for the first time. + -} watchFileSize :: (MonadIO m, MonadMask m) => FilePath -> MeterUpdate -> m a -> m a watchFileSize f p a = bracket - (liftIO $ forkIO $ watcher zeroBytesProcessed) + (liftIO $ forkIO $ watcher =<< getsz) (liftIO . void . tryIO . killThread) (const a) where watcher oldsz = do - v <- catchMaybeIO $ toBytesProcessed <$> getFileSize f - newsz <- case v of - Just sz | sz /= oldsz -> do - p sz - return sz - _ -> return oldsz threadDelay 500000 -- 0.5 seconds - watcher newsz + sz <- getsz + when (sz > oldsz) $ + p sz + watcher sz + getsz = catchDefaultIO zeroBytesProcessed $ + toBytesProcessed <$> getFileSize f data OutputHandler = OutputHandler { quietMode :: Bool |