From efef527d5b2e42e261fa7af6947aad6553426ebe Mon Sep 17 00:00:00 2001
From: Joey Hess <joey@kitenet.net>
Date: Sun, 12 Oct 2014 14:32:56 -0400
Subject: Merge from git-annex.

Includes changing to new exceptions library, and some whitespace fixes.
---
 Utility/Metered.hs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

(limited to 'Utility/Metered.hs')

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.
  -
-- 
cgit v1.2.3