git-annex/Logs/Chunk/Pure.hs
Joey Hess 80cc554c82 add ChunkMethod type and make Logs.Chunk use it, rather than assuming fixed size chunks (so eg, rolling hash chunks can be supported later)
If a newer git-annex starts logging something else in the chunk log, it
won't be used by this version, but it will be preserved when updating the
log.
2014-07-28 13:19:08 -04:00

55 lines
1.2 KiB
Haskell

{- Chunk logs, pure operations.
-
- Copyright 2014 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Logs.Chunk.Pure
( ChunkMethod(..)
, ChunkSize
, ChunkCount
, ChunkLog
, parseLog
, showLog
) where
import Common.Annex
import Logs.MapLog
import Data.Int
-- Currently chunks are all fixed size, but other chunking methods
-- may be added.
data ChunkMethod = FixedSizeChunks ChunkSize | UnknownChunks String
deriving (Ord, Eq)
type ChunkSize = Int64
-- 0 when chunks are no longer present
type ChunkCount = Integer
type ChunkLog = MapLog (UUID, ChunkMethod) ChunkCount
parseChunkMethod :: String -> ChunkMethod
parseChunkMethod s = maybe (UnknownChunks s) FixedSizeChunks (readish s)
showChunkMethod :: ChunkMethod -> String
showChunkMethod (FixedSizeChunks sz) = show sz
showChunkMethod (UnknownChunks s) = s
parseLog :: String -> ChunkLog
parseLog = parseMapLog fieldparser valueparser
where
fieldparser s =
let (u,m) = separate (== sep) s
in Just (toUUID u, parseChunkMethod m)
valueparser = readish
showLog :: ChunkLog -> String
showLog = showMapLog fieldshower valueshower
where
fieldshower (u, m) = fromUUID u ++ sep : showChunkMethod m
valueshower = show
sep :: Char
sep = ':'