git-annex/Remote/Helper/Http.hs
Joey Hess 4f657aa14e add getFileSize, which can get the real size of a large file on Windows
Avoid using fileSize which maxes out at just 2 gb on Windows.
Instead, use hFileSize, which doesn't have a bounded size.
Fixes support for files > 2 gb on Windows.

Note that the InodeCache code only needs to compare a file size,
so it doesn't matter it the file size wraps. So it has been
left as-is. This was necessary both to avoid invalidating existing inode
caches, and because the code passed FileStatus around and would have become
more expensive if it called getFileSize.

This commit was sponsored by Christian Dietrich.
2015-01-20 17:09:24 -04:00

85 lines
2.7 KiB
Haskell

{- helpers for remotes using http
-
- Copyright 2014 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE BangPatterns #-}
module Remote.Helper.Http where
import Common.Annex
import Types.StoreRetrieve
import Utility.Metered
import Remote.Helper.Special
import Network.HTTP.Client (RequestBody(..), Response, responseStatus, responseBody, BodyReader, NeedsPopper)
import Network.HTTP.Types
import qualified Data.ByteString.Lazy as L
import qualified Data.ByteString as S
import Control.Concurrent
-- A storer that expects to be provided with a http RequestBody containing
-- the content to store.
--
-- Implemented as a fileStorer, so that the content can be streamed
-- from the file in constant space.
httpStorer :: (Key -> RequestBody -> Annex Bool) -> Storer
httpStorer a = fileStorer $ \k f m -> a k =<< liftIO (httpBodyStorer f m)
-- Reads the file and generates a streaming request body, that will update
-- the meter as it's sent.
httpBodyStorer :: FilePath -> MeterUpdate -> IO RequestBody
httpBodyStorer src m = do
size <- getFileSize src
let streamer sink = withMeteredFile src m $ \b -> byteStringPopper b sink
return $ RequestBodyStream (fromInteger size) streamer
byteStringPopper :: L.ByteString -> NeedsPopper () -> IO ()
byteStringPopper b sink = do
mvar <- newMVar $ L.toChunks b
let getnextchunk = modifyMVar mvar $ \v ->
case v of
[] -> return ([], S.empty)
(c:cs) -> return (cs, c)
sink getnextchunk
{- Makes a Popper that streams a given number of chunks of a given
- size from the handle, updating the meter as the chunks are read. -}
handlePopper :: Integer -> Int -> MeterUpdate -> Handle -> NeedsPopper () -> IO ()
handlePopper numchunks chunksize meterupdate h sink = do
mvar <- newMVar zeroBytesProcessed
let getnextchunk = do
sent <- takeMVar mvar
if sent >= target
then do
putMVar mvar sent
return S.empty
else do
b <- S.hGet h chunksize
let !sent' = addBytesProcessed sent chunksize
putMVar mvar sent'
meterupdate sent'
return b
sink getnextchunk
where
target = toBytesProcessed (numchunks * fromIntegral chunksize)
-- Reads the http body and stores it to the specified file, updating the
-- meter as it goes.
httpBodyRetriever :: FilePath -> MeterUpdate -> Response BodyReader -> IO ()
httpBodyRetriever dest meterupdate resp
| responseStatus resp /= ok200 = error $ show $ responseStatus resp
| otherwise = bracket (openBinaryFile dest WriteMode) hClose (go zeroBytesProcessed)
where
reader = responseBody resp
go sofar h = do
b <- reader
if S.null b
then return ()
else do
let sofar' = addBytesProcessed sofar $ S.length b
S.hPut h b
meterupdate sofar'
go sofar' h