diff options
Diffstat (limited to 'Utility/Metered.hs')
| -rw-r--r-- | Utility/Metered.hs | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/Utility/Metered.hs b/Utility/Metered.hs index 0d94c1c..4618aec 100644 --- a/Utility/Metered.hs +++ b/Utility/Metered.hs @@ -16,6 +16,7 @@ import qualified Data.ByteString as S import System.IO.Unsafe import Foreign.Storable (Storable(sizeOf)) import System.Posix.Types +import Data.Int {- An action that can be run repeatedly, updating it on the bytes processed. - @@ -23,6 +24,9 @@ import System.Posix.Types - far, *not* an incremental amount since the last call. -} type MeterUpdate = (BytesProcessed -> IO ()) +nullMeterUpdate :: MeterUpdate +nullMeterUpdate _ = return () + {- Total number of bytes processed so far. -} newtype BytesProcessed = BytesProcessed Integer deriving (Eq, Ord, Show) @@ -31,6 +35,10 @@ class AsBytesProcessed a where toBytesProcessed :: a -> BytesProcessed fromBytesProcessed :: BytesProcessed -> a +instance AsBytesProcessed BytesProcessed where + toBytesProcessed = id + fromBytesProcessed = id + instance AsBytesProcessed Integer where toBytesProcessed i = BytesProcessed i fromBytesProcessed (BytesProcessed i) = i @@ -39,6 +47,10 @@ instance AsBytesProcessed Int where toBytesProcessed i = BytesProcessed $ toInteger i fromBytesProcessed (BytesProcessed i) = fromInteger i +instance AsBytesProcessed Int64 where + toBytesProcessed i = BytesProcessed $ toInteger i + fromBytesProcessed (BytesProcessed i) = fromInteger i + instance AsBytesProcessed FileOffset where toBytesProcessed sz = BytesProcessed $ toInteger sz fromBytesProcessed (BytesProcessed sz) = fromInteger sz @@ -77,6 +89,13 @@ meteredWriteFile :: MeterUpdate -> FilePath -> L.ByteString -> IO () meteredWriteFile meterupdate f b = withBinaryFile f WriteMode $ \h -> meteredWrite meterupdate h b +{- Applies an offset to a MeterUpdate. This can be useful when + - performing a sequence of actions, such as multiple meteredWriteFiles, + - that all update a common meter progressively. Or when resuming. + -} +offsetMeterUpdate :: MeterUpdate -> BytesProcessed -> MeterUpdate +offsetMeterUpdate base offset = \n -> base (offset `addBytesProcessed` n) + {- This is like L.hGetContents, but after each chunk is read, a meter - is updated based on the size of the chunk. - |