diff options
author | 2011-11-15 23:48:50 -0400 | |
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committer | 2011-11-15 23:51:24 -0400 | |
commit | e83b966eb5197171a6af46595049d661c4229c58 (patch) | |
tree | 7bf1e84cfd19c34906a981bb088b50f0717351f3 | |
parent | 21a925dcf1ebe088b5c64da0ce159ffb6d535f04 (diff) |
cleanup
-rw-r--r-- | Git/UnionMerge.hs | 39 | ||||
-rw-r--r-- | doc/todo/optimise_git-annex_merge.mdwn | 6 |
2 files changed, 27 insertions, 18 deletions
diff --git a/Git/UnionMerge.hs b/Git/UnionMerge.hs index c86d69979..a2344e59d 100644 --- a/Git/UnionMerge.hs +++ b/Git/UnionMerge.hs @@ -42,25 +42,27 @@ merge_index :: CatFileHandle -> Repo -> [String] -> IO () merge_index h repo bs = update_index_via repo $ map (\b -> merge_tree_index b h repo) bs -update_index :: Repo -> [String] -> IO () -update_index repo ls = update_index_via repo [\h -> mapM_ (sendContent h) ls] - {- Feeds content into update-index. Later items in the list can override - earlier ones, so the list can be generated from any combination of - ls_tree, merge_trees, and merge_tree_index. -} -update_index_via :: Repo -> [Handle -> IO ()] -> IO () -update_index_via repo ls = do +update_index :: Repo -> [String] -> IO () +update_index repo ls = update_index_via repo [\s -> mapM_ s ls] + +type Streamer = (String -> IO ()) -> IO () + +{- Streams content into update-index. -} +update_index_via :: Repo -> [Streamer] -> IO () +update_index_via repo as = do (p, h) <- hPipeTo "git" (toCommand $ Git.gitCommandLine params repo) - forM_ ls $ \l -> l h + forM_ as (stream h) hClose h forceSuccess p where params = map Param ["update-index", "-z", "--index-info"] - -sendContent :: Handle -> String -> IO () -sendContent h s = do - hPutStr h s - hPutStr h "\0" + stream h a = a (streamer h) + streamer h s = do + hPutStr h s + hPutStr h "\0" {- Generates a line suitable to be fed into update-index, to add - a given file with a given sha. -} @@ -68,17 +70,17 @@ update_index_line :: String -> FilePath -> String update_index_line sha file = "100644 blob " ++ sha ++ "\t" ++ file {- Gets the contents of a tree. -} -ls_tree :: String -> Repo -> Handle -> IO () -ls_tree x repo h = mapM_ (sendContent h) =<< pipeNullSplit params repo +ls_tree :: String -> Repo -> Streamer +ls_tree x repo streamer = mapM_ streamer =<< pipeNullSplit params repo where params = map Param ["ls-tree", "-z", "-r", "--full-tree", x] {- For merging two trees. -} -merge_trees :: String -> String -> CatFileHandle -> Repo -> Handle -> IO () +merge_trees :: String -> String -> CatFileHandle -> Repo -> Streamer merge_trees x y h = calc_merge h $ "diff-tree":diff_opts ++ [x, y] {- For merging a single tree into the index. -} -merge_tree_index :: String -> CatFileHandle -> Repo -> Handle -> IO () +merge_tree_index :: String -> CatFileHandle -> Repo -> Streamer merge_tree_index x h = calc_merge h $ "diff-index":diff_opts ++ ["--cached", x] diff_opts :: [String] @@ -86,12 +88,13 @@ diff_opts = ["--raw", "-z", "-r", "--no-renames", "-l0"] {- Calculates how to perform a merge, using git to get a raw diff, - and returning a list suitable for update_index. -} -calc_merge :: CatFileHandle -> [String] -> Repo -> Handle -> IO () -calc_merge ch differ repo ih = pipeNullSplit (map Param differ) repo >>= go +calc_merge :: CatFileHandle -> [String] -> Repo -> Streamer +calc_merge ch differ repo streamer = gendiff >>= go where + gendiff = pipeNullSplit (map Param differ) repo go [] = return () go (info:file:rest) = mergeFile info file ch repo >>= - maybe (go rest) (\l -> sendContent ih l >> go rest) + maybe (go rest) (\l -> streamer l >> go rest) go (_:[]) = error "calc_merge parse error" {- Given an info line from a git raw diff, and the filename, generates diff --git a/doc/todo/optimise_git-annex_merge.mdwn b/doc/todo/optimise_git-annex_merge.mdwn index 2df196cfd..91d18ebd7 100644 --- a/doc/todo/optimise_git-annex_merge.mdwn +++ b/doc/todo/optimise_git-annex_merge.mdwn @@ -15,3 +15,9 @@ merged. This could be reduced to a single call to `git-cat-file --batch`, There is already a Git.CatFile library that can do this easily. --[[Joey]] > This is now done, part above remains todo. --[[Joey]] + +--- + +Merging used to use memory proportional to the size of the diff. It now +streams data, running in constant space. This probably sped it up a lot, +as there's much less allocation and GC action. --[[Joey]] |