1{- git hash-object interface
2 -
3 - Copyright 2011-2019 Joey Hess <id@joeyh.name>
4 -
5 - Licensed under the GNU AGPL version 3 or higher.
6 -}
7
8{-# LANGUAGE CPP #-}
9
10module Git.HashObject where
11
12import Common
13import Git
14import Git.Sha
15import Git.Command
16import Git.Types
17import qualified Utility.CoProcess as CoProcess
18import Utility.Tmp
19
20import qualified Data.ByteString as S
21import qualified Data.ByteString.Char8 as S8
22import qualified Data.ByteString.Lazy as L
23import Data.ByteString.Builder
24
25type HashObjectHandle = CoProcess.CoProcessHandle
26
27hashObjectStart :: Bool -> Repo -> IO HashObjectHandle
28hashObjectStart writeobject = gitCoProcessStart True $ catMaybes
29	[ Just (Param "hash-object")
30	, if writeobject then Just (Param "-w") else Nothing
31	, Just (Param "--stdin-paths")
32	, Just (Param "--no-filters")
33	]
34
35hashObjectStop :: HashObjectHandle -> IO ()
36hashObjectStop = CoProcess.stop
37
38{- Injects a file into git, returning the Sha of the object. -}
39hashFile :: HashObjectHandle -> RawFilePath -> IO Sha
40hashFile h file = CoProcess.query h send receive
41  where
42	send to = S8.hPutStrLn to =<< absPath file
43	receive from = getSha "hash-object" $ S8.hGetLine from
44
45class HashableBlob t where
46	hashableBlobToHandle :: Handle -> t -> IO ()
47
48instance HashableBlob L.ByteString where
49	hashableBlobToHandle = L.hPut
50
51instance HashableBlob S.ByteString where
52	hashableBlobToHandle = S.hPut
53
54instance HashableBlob Builder where
55	hashableBlobToHandle = hPutBuilder
56
57{- Injects a blob into git. Unfortunately, the current git-hash-object
58 - interface does not allow batch hashing without using temp files. -}
59hashBlob :: HashableBlob b => HashObjectHandle -> b -> IO Sha
60hashBlob h b = withTmpFile "hash" $ \tmp tmph -> do
61	hashableBlobToHandle tmph b
62	hClose tmph
63	hashFile h (toRawFilePath tmp)
64
65{- Injects some content into git, returning its Sha.
66 -
67 - Avoids using a tmp file, but runs a new hash-object command each
68 - time called. -}
69hashObject :: ObjectType -> String -> Repo -> IO Sha
70hashObject objtype content = hashObject' objtype (flip hPutStr content)
71
72hashObject' :: ObjectType -> (Handle -> IO ()) -> Repo -> IO Sha
73hashObject' objtype writer repo = getSha subcmd $
74	pipeWriteRead (map Param params) (Just writer) repo
75  where
76	subcmd = "hash-object"
77	params = [subcmd, "-t", decodeBS (fmtObjectType objtype), "-w", "--stdin", "--no-filters"]
78