halfs-0.2: Halfs/TheInodeMap.hs

-- |Basically hidden under the FSRoot module (also used by SyncStructures)

module Halfs.TheInodeMap (TheInodeMap(..), emptyInodeMap,
                          freeInode) where

import Data.Integral(INInt)

-- |Keeps track of freed inodes so we can reuse their space.
data TheInodeMap = TheInodeMap {
                                freeInodes :: [INInt] -- Inode Numbers
                               ,imDirty    :: Bool
                               ,imMaxNum   :: INInt
                               }

emptyInodeMap :: INInt -- first free inode number
              -> TheInodeMap
emptyInodeMap n =  TheInodeMap [] True n

-- |Add this inode to the free list.
freeInode :: TheInodeMap -> INInt -> TheInodeMap
freeInode im@TheInodeMap{freeInodes=l} i
    = im{freeInodes=i:l, imDirty=True}