git-annex/Utility/DiskFree.hs
Joey Hess e38a839a80 Rewrote free disk space checking code
Moving the portability handling into a small C library cleans up things
a lot, avoiding the pain of unpacking structs from inside haskell code.
2012-03-22 17:32:47 -04:00

32 lines
692 B
Haskell

{- disk free space checking
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE ForeignFunctionInterface #-}
module Utility.DiskFree ( getDiskFree ) where
import Common
import Foreign.C.Types
import Foreign.C.String
import Foreign.C.Error
foreign import ccall unsafe "diskfree.h diskfree" c_diskfree
:: CString -> IO CULLong
getDiskFree :: String -> IO (Maybe Integer)
getDiskFree path = withFilePath path $ \c_path -> do
free <- c_diskfree c_path
ifM (safeErrno <$> getErrno)
( return $ Just $ toInteger free
, do
Errno i <- getErrno
print i
return Nothing
)
where
safeErrno (Errno v) = v == 0