{- |

Module : $Header$

Description : ConservativityChecker for propositional logic

Copyright : (c) Dominik Luecke, Uni Bremen 2007

License : similar to LGPL, see HetCATS/LICENSE.txt or LIZENZ.txt

Maintainer : luecke@informatik.uni-bremen.de

Stability : experimental

Portability : portable

THe QBF solver sKizzo is used for conservativity checking. This is the

code connecting it to Hets

-}

module Propositional.Conservativity

(

conserCheck

)

where

import Common.AS_Annotation

import Common.Result

import Common.Consistency

import qualified Data.Set as Set

import Common.Id

import System.Exit

import System.IO.Unsafe

import Control.Monad

import qualified Data.Map as Map

import Common.Id

import System.Cmd

import System.Directory

import Data.Time.Clock

import System.Process

-- Propositional Stuff

import Propositional.Sign

import Propositional.AS_BASIC_Propositional

import Propositional.Morphism

import Propositional.Prop2CNF

import Propositional.Conversions

import Propositional.Tools

proverName :: String

proverName = "sKizzo"

defOptions :: String

defOptions = "-timeout 60"

-- | Conservativity Check for Propositional Logic

conserCheck :: (Sign, [Named FORMULA]) -- ^ Initial sign and formulas

-> Morphism -- ^ morhpism between specs

-> [Named FORMULA] -- ^ Formulas of extended spec

-> Result (Maybe (Conservativity, [FORMULA]))

conserCheck (_, inSens) mor cSens=

do

let cForms = getFormulas cSens

inSig = source mor

cSig = target mor

inFormsM <- mapM (mapSentence mor) $ getFormulas inSens

let checkForm =

Implication

(Conjunction inFormsM nullRange)

(Conjunction cForms nullRange)

nullRange

result <- unsafePerformIO $

doConservCheck inSig cSig checkForm

return result

-- | Extraction of needed formulas, removes all Axioms and Annotations

getFormulas :: [Named FORMULA] -> [FORMULA]

getFormulas sens = foldl (\out sen->

out ++

(

if (isAxiom sen)

then

[sentence sen]

else

[]

)

) [] sens

doConservCheck :: Sign -- ^ Initial Sign

-> Sign -- ^ Extended Sign

-> FORMULA -- ^ QBF Formula to Prove

-> IO (Result (Maybe (Conservativity, [FORMULA])))

doConservCheck inSig exSig form =

do

(oSig , cnf) <- translateToCNF (exSig, [makeNamed "QBF Formula" form])

if (length cnf /= 1)

then

fail "Translation error"

else

do

let iMap = createSignMap oSig 1 Map.empty

iSym = items inSig

eSym = (items oSig) `Set.difference` iSym

qdim <- showQDimacs iSym eSym iMap cnf

res <- runSKizzo qdim

return (return (Just (res,[])))

-- | Printer for QDimacs Format

showQDimacs :: Set.Set Id -- ^ Symbols of initial Sign

-> Set.Set Id -- ^ New symbols of extended Sign

-> Map.Map Token Integer -- ^ Map of Symbols

-> [Named FORMULA] -- ^ Formulas to Translate

-> IO String

showQDimacs inSym exSym sigMap forms =

do

let fforms = concat $ map flatten $ map sentence forms

numVars = Set.size inSym + Set.size exSym

return $ "c Conservativity Problem Created by Hets \n" ++

"p cnf " ++ show numVars ++ " " ++

(show $ length fforms) ++ "\n" ++

"a " ++ Set.fold

(\sym str ->

(show $ Map.findWithDefault 0 (head $

getSimpleId sym) sigMap) ++ " " ++ str

) "" inSym ++ "0\n" ++

"e " ++ Set.fold

(\sym str ->

(show $ Map.findWithDefault 0 (head $

getSimpleId sym) sigMap) ++ " " ++ str

) "" exSym ++ "0\n" ++

(\tflAxs ->

case tflAxs of

[] -> ""

_ -> "c Axioms\n" ++

(foldl (\sr xv -> sr ++

mapClause xv sigMap) "" tflAxs)

) fforms

-- | gets simple Id

getSimpleId :: Id -> [Token]

getSimpleId (Id toks _ _) = toks

-- | Runs sKizzo that has to reside in your path

runSKizzo :: String -- ^ File in qdimacs syntax

-> IO Conservativity

runSKizzo qd =

do

hasProgramm <- system ("which " ++ proverName

++ " > /dev/null 2> /dev/null")

case hasProgramm of

ExitFailure _ ->

do

return $ Unknown (proverName ++ " not found in your $PATH$")

ExitSuccess ->

do

tmp <- getTemporaryDirectory

time <- getCurrentTime

let path = tmp ++ "/sKizzoTemp_" ++

(replaceBaddies $ show time) ++ ".qdimacs"

writeFile path qd

let command = proverName ++ " " ++ defOptions ++ " " ++ path

(_,_,_,pid) <- runInteractiveCommand command

exCode <- waitForProcess pid

removeFile path

case exCode of

ExitFailure 10 -> return Cons

ExitFailure 20 -> return Inconsistent

ExitFailure 30 -> return $ Unknown "Timeout"

ExitFailure 40 -> return $ Unknown "Cannot solve"

ExitFailure 250 -> return $ Unknown "Out of memory"

ExitFailure 251 -> return $ Unknown "sKizzo crashed"

ExitFailure 254 -> return $ Unknown "File not found"

ExitFailure (-4) -> return $ Unknown "Parse error"

ExitFailure (-5) -> return $ Unknown "sKizzo crashed"

ExitFailure (-6) -> return $ Unknown "Out of memory"

n -> return $ Unknown $ "Unkown, exit was: " ++

show n

-- | Helper to filter out problematic characters

replaceBaddies :: String -> String

replaceBaddies s = map (\x -> case x of

' ' -> '_'

':' -> '_'

y -> y

) s