add inodes to kqueue's directory cache

This is necessary to generate events when a file is deleted and immediately
replaced. Otherwise, the cache will have the old file, and so no event
would be generated.

Use of getFileStatus is suboptimal, it would be faster to use
the inode returned by readdir -- but getDirectoryContents does not expose
it, so I'd have to copy and modify a lot of low-level code.
This commit is contained in:
Joey Hess 2012-07-17 15:57:49 -04:00
parent cfccfc19e0
commit e816776a62

View file

@ -22,6 +22,7 @@ module Utility.Kqueue (
import Common
import Utility.Types.DirWatcher
import System.Posix.Directory
import System.Posix.Types
import Foreign.C.Types
import Foreign.C.Error
@ -62,15 +63,19 @@ type DirMap = M.Map Fd DirInfo
{- A directory, and its last known contents (with filenames relative to it) -}
data DirInfo = DirInfo
{ dirName :: FilePath
, dirCache :: S.Set FilePath
, dirCache :: S.Set (FilePath, FileID)
}
deriving (Show)
getDirInfo :: FilePath -> IO DirInfo
getDirInfo dir = do
contents <- S.fromList . filter (not . dirCruft)
<$> getDirectoryContents dir
l <- filter (not . dirCruft) <$> getDirectoryContents dir
contents <- S.fromList <$> mapM addinode l
return $ DirInfo dir contents
where
addinode f = do
inode <- fileID <$> getFileStatus (dir </> f)
return (f, inode)
{- Difference between the dirCaches of two DirInfos. -}
(//) :: DirInfo -> DirInfo -> [Change]
@ -78,7 +83,7 @@ oldc // newc = deleted ++ added
where
deleted = calc Deleted oldc newc
added = calc Added newc oldc
calc a x y = map a . map (dirName x </>) $
calc a x y = map a . map (dirName x </>) . map fst $
S.toList $ S.difference (dirCache x) (dirCache y)
{- Builds a map of directories in a tree, possibly pruning some.
@ -99,7 +104,7 @@ scanRecursive topdir prune = M.fromList <$> walk [] [topdir]
case mfd of
Nothing -> walk c rest
Just fd -> do
let subdirs = map (dir </>) $
let subdirs = map (dir </>) . map fst $
S.toList $ dirCache info
walk ((fd, info):c) (subdirs ++ rest)
@ -123,7 +128,8 @@ removeSubDir dirmap dir = do
findDirContents :: DirMap -> FilePath -> [FilePath]
findDirContents dirmap dir = concatMap absolutecontents $ search
where
absolutecontents i = map (dirName i </>) (S.toList $ dirCache i)
absolutecontents i = map (dirName i </>)
(map fst $ S.toList $ dirCache i)
search = map snd $ M.toList $
M.filter (\i -> dirName i == dir) dirmap