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Diffstat (limited to 'CGroup')
| -rw-r--r-- | CGroup/Types.hs | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/CGroup/Types.hs b/CGroup/Types.hs new file mode 100644 index 0000000..53ff4fa --- /dev/null +++ b/CGroup/Types.hs @@ -0,0 +1,51 @@ +-- | +-- Module: CGroup.Types +-- Copyright: (c) 2014 Tomislav Viljetić +-- License: BSD3 +-- Maintainer: Tomislav Viljetić <tomislav@viljetic.de> +-- + +module CGroup.Types + ( CGroup + , cgroup + , cgroupPath + , ProcessID + ) where + +import Data.Monoid +import qualified System.FilePath as FP + + +-- | A 'CGroup' is defined by a mount point and a cgroup name. +-- +-- The mount point specifies where the cgroup hierarchy is mounted. +-- The cgroup name is a 'FilePath' relative to the mount point. +data CGroup = CGroup { mountPoint, cgroupName :: FilePath } + deriving Show + + +-- | @'cgroup' mountPoint cgroupName@ is a smart constructor for 'CGroup'. +-- +-- It will return 'Nothing' if @cgroupName@ could point outside +-- @mountPoint@ in order to prevent directory traversal attacks. +cgroup :: FilePath -> FilePath -> Maybe CGroup +cgroup mp0 cgn0 + | ".." `elem` parts = Nothing + | FP.isAbsolute cgn = Nothing + | otherwise = Just CGroup { mountPoint = mp, cgroupName = cgn } + where + mp = normaliseMountPoint mp0 + cgn = normaliseCGroupName cgn0 + parts = FP.splitDirectories cgn + normaliseMountPoint = FP.addTrailingPathSeparator . FP.normalise + normaliseCGroupName = FP.dropTrailingPathSeparator . FP.normalise + + +-- | @'cgroupPath' g@ returns the absolute 'FilePath' of cgroup @g@. +cgroupPath :: CGroup -> FilePath +cgroupPath CGroup { mountPoint = mp, cgroupName = cgn } = + mp <> cgn + + +-- | A 'ProcessID' defines a task / process. +type ProcessID = Int |