git-annex/Git/LsTree.hs
2015-01-21 12:50:09 -04:00

65 lines
1.6 KiB
Haskell

{- git ls-tree interface
-
- Copyright 2011 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.LsTree (
TreeItem(..),
lsTree,
lsTreeParams,
lsTreeFiles,
parseLsTree
) where
import Numeric
import Control.Applicative
import System.Posix.Types
import Common
import Git
import Git.Command
import Git.Sha
import Git.FilePath
import qualified Git.Filename
data TreeItem = TreeItem
{ mode :: FileMode
, typeobj :: String
, sha :: String
, file :: TopFilePath
} deriving Show
{- Lists the complete contents of a tree, recursing into sub-trees,
- with lazy output. -}
lsTree :: Ref -> Repo -> IO [TreeItem]
lsTree t repo = map parseLsTree
<$> pipeNullSplitZombie (lsTreeParams t) repo
lsTreeParams :: Ref -> [CommandParam]
lsTreeParams t = [ Params "ls-tree --full-tree -z -r --", File $ fromRef t ]
{- Lists specified files in a tree. -}
lsTreeFiles :: Ref -> [FilePath] -> Repo -> IO [TreeItem]
lsTreeFiles t fs repo = map parseLsTree <$> pipeNullSplitStrict ps repo
where
ps = [Params "ls-tree --full-tree -z --", File $ fromRef t] ++ map File fs
{- Parses a line of ls-tree output.
- (The --long format is not currently supported.) -}
parseLsTree :: String -> TreeItem
parseLsTree l = TreeItem
{ mode = fst $ Prelude.head $ readOct m
, typeobj = t
, sha = s
, file = asTopFilePath $ Git.Filename.decode f
}
where
-- l = <mode> SP <type> SP <sha> TAB <file>
-- All fields are fixed, so we can pull them out of
-- specific positions in the line.
(m, past_m) = splitAt 7 l
(t, past_t) = splitAt 4 past_m
(s, past_s) = splitAt shaSize $ Prelude.tail past_t
f = Prelude.tail past_s