git-annex/Command/DiffDriver.hs
Joey Hess c19211774f
use filepath-bytestring for annex object manipulations
git-annex find is now RawFilePath end to end, no string conversions.
So is git-annex get when it does not need to get anything.
So this is a major milestone on optimisation.

Benchmarks indicate around 30% speedup in both commands.

Probably many other performance improvements. All or nearly all places
where a file is statted use RawFilePath now.
2019-12-11 15:25:07 -04:00

98 lines
2.5 KiB
Haskell

{- git-annex command
-
- Copyright 2014 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Command.DiffDriver where
import Command
import Annex.Content
import Annex.Link
import Git.Types
cmd :: Command
cmd = dontCheck repoExists $
command "diffdriver" SectionPlumbing
"external git diff driver shim"
("-- cmd --") (withParams seek)
seek :: CmdParams -> CommandSeek
seek = withWords (commandAction . start)
start :: [String] -> CommandStart
start opts = do
let (req, differ) = parseReq opts
void $ liftIO . exitBool =<< liftIO . differ =<< fixupReq req
stop
data Req
= Req
{ rPath :: FilePath
, rOldFile :: FilePath
, rOldHex :: String
, rOldMode :: String
, rNewFile :: FilePath
, rNewHex :: String
, rNewMode ::String
}
| UnmergedReq
{ rPath :: FilePath
}
type Differ = Req -> IO Bool
serializeReq :: Req -> [CommandParam]
serializeReq req@(UnmergedReq {}) = [Param $ rPath req]
serializeReq req@(Req {}) = map Param
[ rPath req
, rOldFile req
, rOldHex req
, rOldMode req
, rNewFile req
, rNewHex req
, rNewMode req
]
parseReq :: [String] -> (Req, Differ)
parseReq opts = case separate (== "--") opts of
(c:ps, l) -> (mk l, externalDiffer c ps)
([],_) -> badopts
where
mk (path:old_file:old_hex:old_mode:new_file:new_hex:new_mode:[]) =
Req
{ rPath = path
, rOldFile = old_file
, rOldHex = old_hex
, rOldMode = old_mode
, rNewFile = new_file
, rNewHex = new_hex
, rNewMode = new_mode
}
mk (unmergedpath:[]) = UnmergedReq { rPath = unmergedpath }
mk _ = badopts
badopts = giveup $ "Unexpected input: " ++ unwords opts
{- Check if either file is a symlink to a git-annex object,
- which git-diff will leave as a normal file containing the link text.
- Adjust the Req to instead point to the actual location of the annexed
- object (which may or may not exist). -}
fixupReq :: Req -> Annex Req
fixupReq req@(UnmergedReq {}) = return req
fixupReq req@(Req {}) =
check rOldFile rOldMode (\r f -> r { rOldFile = f }) req
>>= check rNewFile rNewMode (\r f -> r { rNewFile = f })
where
check getfile getmode setfile r = case readTreeItemType (encodeBS' (getmode r)) of
Just TreeSymlink -> do
v <- getAnnexLinkTarget' (toRawFilePath (getfile r)) False
case parseLinkTargetOrPointer =<< v of
Nothing -> return r
Just k -> withObjectLoc k $
pure . setfile r . fromRawFilePath
_ -> return r
externalDiffer :: String -> [String] -> Differ
externalDiffer c ps = \req -> boolSystem c (map Param ps ++ serializeReq req )