Haskell virus scanner

hs-clamscan.hs

import qualified Data.ByteString as BS
import qualified Data.ByteString.Char8 as BSC
import System.Process.ByteString
import System.Exit

data VirusScanResult
  = VSRClean
  | VSRVirusFound BS.ByteString
    deriving (Eq, Ord, Show)

virusScan :: BS.ByteString -> IO VirusScanResult
virusScan testData = do
  ( exitCode, stdout, stderr ) <- readProcessWithExitCode "clamscan" ["-"] testData
  -- see "man clamscan"
  case exitCode of
    ExitSuccess -> return VSRClean
    ExitFailure 1 -> return (VSRVirusFound stdout)
    ExitFailure _ -> fail ("Virus scan failed: " ++ BSC.unpack stderr)