git-annex/Utility/DiskFree.hs
2013-03-13 14:54:52 -04:00

38 lines
772 B
Haskell

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