Example #1
0
        private Dictionary <string, LocalPair> IsEventStrongFair(Dictionary <string, LocalPair> StronglyConnectedComponents, Dictionary <string, List <string> > OutgoingTransitionTable)
        {
            List <string> EngagedEvents = new List <string>();

            EngagedEvents.Add(Constants.TAU);

            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                ConfigurationBase componetStep = value.Value.configuration;
                if (!EngagedEvents.Contains(componetStep.Event) && (StronglyConnectedComponents.Count > 1 || !componetStep.IsDeadLock)) //&& componetStep.Event != Constants.TERMINATION
                {
                    EngagedEvents.Add(componetStep.Event);
                }
            }

            List <string> badStates = new List <string>();

            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                string    componet = value.Key;
                LocalPair pair     = value.Value;

                foreach (string evt in pair.Enabled)
                {
                    if (!EngagedEvents.Contains(evt))
                    {
                        badStates.Add(componet);
                    }
                }
            }

            if (badStates.Count > 0)
            {
                foreach (string var in badStates)
                {
                    StronglyConnectedComponents.Remove(var);
                }

                if (StronglyConnectedComponents.Count > 0)
                {
                    Dictionary <string, LocalPair> value = TarjanModelChecking2(StronglyConnectedComponents, OutgoingTransitionTable);
                    if (value != null)
                    {
                        return(value);
                    }
                }

                return(null);
            }
            else
            {
                //This SCC is fair.
                return(StronglyConnectedComponents);
                //return true;
            }
        }
Example #2
0
        private Dictionary <string, LocalPair> IsProcesstWeakFair(Dictionary <string, LocalPair> StronglyConnectedComponents)
        {
            List <string>    AlwaysEnabledProcesses = new List <string>();
            HashSet <string> EngagedProcesses       = new HashSet <string>();

            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                string    componet     = value.Key;
                LocalPair componetStep = value.Value;

                if (AlwaysEnabledProcesses.Count > 0)
                {
                    AlwaysEnabledProcesses = Ultility.Ultility.Intersect(AlwaysEnabledProcesses, componetStep.Enabled);
                }
                else
                {
                    AlwaysEnabledProcesses.AddRange(componetStep.Enabled);
                }
                //The above gets the processes which are always enabled during the SCC.

                //The below gets the processes which made some progress during the SCC.
                if (componetStep.configuration.ParticipatingProcesses != null)
                {
                    string[] indexes = componetStep.configuration.ParticipatingProcesses;
                    foreach (string s in indexes)
                    {
                        if (!EngagedProcesses.Contains(s))
                        {
                            EngagedProcesses.Add(s);
                        }
                    }
                }
                //The above gets the processes which made some progress during the SCC.
            }

            //discard the SCC if there exists a process which is always enabled but never engaged.
            foreach (string s in AlwaysEnabledProcesses)
            {
                if (!EngagedProcesses.Contains(s))
                {
                    return(null);
                }
            }

            return(StronglyConnectedComponents);
            //return true;
        }
Example #3
0
        private Dictionary <string, LocalPair> IsEventWeakFair(Dictionary <string, LocalPair> StronglyConnectedComponents)
        {
            List <string> AlwaysEnabled = null; //for weak-fair annotation.

            HashSet <string> EngagedEvents = new HashSet <string>();

            EngagedEvents.Add(Constants.TAU);

            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                //string componet = value.Key;
                LocalPair componetStep = value.Value;

                if (!EngagedEvents.Contains(componetStep.configuration.Event) && (StronglyConnectedComponents.Count > 1 || !componetStep.configuration.IsDeadLock)) //componetStep.Event != Constants.TERMINATION &&
                {
                    EngagedEvents.Add(componetStep.configuration.Event);
                }

                if (AlwaysEnabled == null)
                {
                    AlwaysEnabled = new List <string>();
                    AlwaysEnabled.AddRange(componetStep.Enabled);
                }
                else if (AlwaysEnabled.Count > 0)
                {
                    AlwaysEnabled = Ultility.Ultility.Intersect(AlwaysEnabled, componetStep.Enabled);
                }
            }

            //discard the SCC if there exists an event which is always enabled but never engaged.
            for (int j = 0; j < AlwaysEnabled.Count; j++)
            {
                string s = AlwaysEnabled[j];
                if (!EngagedEvents.Contains(s))
                {
                    return(null);
                }
            }

            return(StronglyConnectedComponents);
            //FairSCC = StronglyConnectedComponents;
            //return true;
        }
Example #4
0
        private Dictionary <string, LocalPair> IsGlobalFair(Dictionary <string, LocalPair> StronglyConnectedComponents, Dictionary <string, List <string> > OutgoingTransitionTable)
        {
            //for (int i = 0; i < StronglyConnectedComponents.Count; i++)
            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                string    componet = value.Key;
                LocalPair pair     = value.Value;

                List <string> nextStates = OutgoingTransitionTable[componet];

                foreach (string nextID in pair.Enabled)
                {
                    bool found = false;

                    foreach (string state in nextStates)
                    {
                        if (StronglyConnectedComponents.ContainsKey(state))
                        {
                            if (StronglyConnectedComponents[state].configuration.GetIDWithEvent() == nextID)
                            {
                                found = true;
                                break;
                            }
                        }
                    }

                    if (!found)
                    {
                        return(null);
                    }
                }
            }

            return(StronglyConnectedComponents);
            //return true;
        }
Example #5
0
        private Dictionary <string, LocalPair> IsProcessStrongFair(Dictionary <string, LocalPair> StronglyConnectedComponents, Dictionary <string, List <string> > OutgoingTransitionTable)
        {
            HashSet <string> EngagedProcesses = new HashSet <string>();

            //the following collects the processes which make progress during the SCC.
            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                //string componet = value.Key;
                ConfigurationBase componetStep = value.Value.configuration;

                if (componetStep.ParticipatingProcesses != null)
                {
                    string[] indexes = componetStep.ParticipatingProcesses;
                    if (indexes != null)
                    {
                        for (int j = 0; j < indexes.Length; j++)
                        {
                            if (!EngagedProcesses.Contains(indexes[j]))
                            {
                                EngagedProcesses.Add(indexes[j]);
                            }
                        }
                    }
                }
            }
            //the above collects the processes which make progress during the SCC.

            //the following collects the processes which has been enabled at least once but failed to make progress during the SCC.
            HashSet <string> badStates = new HashSet <string>();

            foreach (KeyValuePair <string, LocalPair> value in StronglyConnectedComponents)
            {
                string    componet     = value.Key;
                LocalPair componetStep = value.Value;

                for (int j = 0; j < componetStep.Enabled.Count; j++)
                {
                    if (!EngagedProcesses.Contains(componetStep.Enabled[j]) && !badStates.Contains(componet))
                    {
                        badStates.Add(componet);
                    }
                }
            }
            //the above collects the processes which has been enabled at least once but failed to make progress during the SCC.

            //if there are bad states, the SCC is not fair.
            if (badStates.Count > 0)
            {
                foreach (string var in badStates)
                {
                    StronglyConnectedComponents.Remove(var);
                }

                if (StronglyConnectedComponents.Count > 0)
                {
                    Dictionary <string, LocalPair> value = TarjanModelChecking2(StronglyConnectedComponents, OutgoingTransitionTable);
                    if (value != null)
                    {
                        return(value);
                    }
                }

                return(null);
            }
            //otherwise, it is fair.
            else
            {
                //This SCC is fair.
                return(StronglyConnectedComponents);
                //return true;
            }
        }
Example #6
0
        public void TarjanModelChecking()
        {
            OutgoingTransitionTable = new Dictionary <string, List <string> >(Ultility.Ultility.MC_INITIAL_SIZE);
            TaskStack = new Stack <LocalPair>(Ultility.Ultility.MC_INITIAL_SIZE);
            DFSData   = new StringDictionary <int[]>(Ultility.Ultility.MC_INITIAL_SIZE);

            List <LocalPair> initials = LocalPair.GetInitialPairsLocal(BA, initialStep);

            if (initials.Count == 0 || !BA.HasAcceptState)
            {
                VerificationResult = VerificationResultType.VALID;
                return;
            }

            for (int z = 0; z < initials.Count; z++)
            {
                LocalPair initState = initials[z];
                TaskStack.Push(initState);
                string ID = initState.GetCompressedState();
                DFSData.Add(ID, new int[] { VISITED_NOPREORDER, 0 });
                OutgoingTransitionTable.Add(ID, new List <string>(8));
            }

            Dictionary <string, LocalPair> SCCPairs = new Dictionary <string, LocalPair>(1024);
            Stack <LocalPair> stepStack             = new Stack <LocalPair>(1024);

            //# Preorder counter
            int i = 0;

            //store the expended event step of a node to avoid multiple invocation of the make one move.
            Dictionary <string, List <LocalPair> > ExpendedNode = new Dictionary <string, List <LocalPair> >(1024);

            //PrintMessage("Start to find the Strongly Connected Component of graph.");

            do
            {
                if (SearchedDepth < TaskStack.Count)
                {
                    SearchedDepth = TaskStack.Count;
                }

                if (JobFinished)
                {
                    return;
                }

                LocalPair         pair    = TaskStack.Peek();
                ConfigurationBase evt     = pair.configuration;
                string            BAState = pair.state;

                string v = pair.GetCompressedState();

                List <string> outgoing = OutgoingTransitionTable[v];

                int[] nodeData = DFSData.GetContainsKey(v);

                if (nodeData[0] == VISITED_NOPREORDER)
                {
                    nodeData[0] = i;
                    i++;
                }

                bool done = true;

                if (ExpendedNode.ContainsKey(v))
                {
                    List <LocalPair> list = ExpendedNode[v];
                    if (list.Count > 0)
                    {
                        //transverse all steps
                        for (int k = list.Count - 1; k >= 0; k--)
                        {
                            LocalPair step = list[k];

                            string tmp = step.GetCompressedState();

                            //if the step is a unvisited step
                            if (DFSData.GetContainsKey(tmp)[0] == VISITED_NOPREORDER)
                            {
                                //only add the first unvisited step
                                //for the second or more unvisited steps, ignore at the monent
                                if (done)
                                {
                                    TaskStack.Push(step);
                                    done = false;
                                    list.RemoveAt(k);
                                }
                            }
                            else
                            {
                                list.RemoveAt(k);
                            }
                        }
                    }
                }
                else
                {
                    //ConfigurationBase[] list = evt.MakeOneMove().ToArray();
                    IEnumerable <ConfigurationBase> list = evt.MakeOneMove();
                    pair.SetEnabled(list, FairnessType);
                    List <LocalPair> product = LocalPair.NextLocal(BA, list, BAState);

                    //count the transitions visited
                    Transitions += product.Count;

                    for (int k = product.Count - 1; k >= 0; k--)
                    {
                        LocalPair step = product[k];
                        string    tmp  = step.GetCompressedState();

                        //if (VisitedWithID.ContainsKey(tmp))
                        int[] data = DFSData.GetContainsKey(tmp);
                        if (data != null)
                        {
                            //update the incoming and outgoing edges
                            //int t = VisitedWithID.GetContainsKey(tmp); //DataStore.DataManager.GetID(tmp);
                            outgoing.Add(tmp);

                            //if this node is still not visited
                            if (data[0] == VISITED_NOPREORDER)
                            {
                                //step.ID = t;
                                //only put the first one to the work list stack.
                                //if there are more than one node to be visited,
                                //simply ignore them and keep its event step in the list.
                                if (done)
                                {
                                    TaskStack.Push(step);
                                    done = false;
                                    product.RemoveAt(k);
                                }
                                else
                                {
                                    product[k] = step;
                                }
                            }
                            //this node is truly visited. can be removed
                            else
                            {
                                product.RemoveAt(k);
                            }
                        }
                        else
                        {
                            //int stateID = VisitedWithID.Count;
                            //VisitedWithID.Add(tmp,false);
                            DFSData.Add(tmp, new int[] { VISITED_NOPREORDER, 0 });

                            OutgoingTransitionTable.Add(tmp, new List <string>(8));
                            //step.ID = stateID;
                            outgoing.Add(tmp);

                            //only put the first one into the stack.
                            if (done)
                            {
                                TaskStack.Push(step);
                                done = false;
                                product.RemoveAt(k);
                            }
                            else
                            {
                                product[k] = step;
                            }
                        }
                    }

                    //create the remaining steps as the expending list for v
                    ExpendedNode.Add(v, product);
                }

                if (done)
                {
                    int lowlinkV  = nodeData[0];
                    int preorderV = lowlinkV;

                    bool selfLoop = false;

                    // Calculate the low link of an explored state
                    for (int j = 0; j < outgoing.Count; j++)
                    {
                        string w = outgoing[j];
                        if (w == v)
                        {
                            selfLoop = true;
                        }

                        int[] wdata = DFSData.GetContainsKey(w);
                        if (wdata[0] != SCC_FOUND)
                        {
                            if (wdata[0] > preorderV)
                            {
                                lowlinkV = Math.Min(lowlinkV, wdata[1]);
                            }
                            else
                            {
                                lowlinkV = Math.Min(lowlinkV, wdata[0]);
                            }
                        }
                    }

                    nodeData[1] = lowlinkV;

                    TaskStack.Pop();

                    // Check whether the current state is the root of the SCC
                    if (lowlinkV == preorderV)
                    {
                        SCCPairs.Add(v, pair);
                        nodeData[0] = SCC_FOUND;

                        bool BuchiFair = pair.state.EndsWith(Constants.ACCEPT_STATE); //for buchi-fair

                        // Get the elements of the SCC from the step stack
                        while (stepStack.Count > 0 && DFSData.GetContainsKey(stepStack.Peek().GetCompressedState())[0] > preorderV)
                        {
                            LocalPair s = stepStack.Pop();
                            string    k = s.GetCompressedState();

                            SCCPairs.Add(k, s);
                            DFSData.GetContainsKey(k)[0] = SCC_FOUND;

                            if (!BuchiFair && s.state.EndsWith(Constants.ACCEPT_STATE))
                            {
                                BuchiFair = true;
                            }
                        }

                        //outgoing.Count == 0 --> deadlock, we need to check //outgoing.Count == 0
                        //StronglyConnectedComponets.Count > 1 || selfLoop -> non-trivial case, we need to check
                        int SCCSize = SCCPairs.Count;

                        if (BuchiFair && (evt.IsDeadLock || SCCSize > 1 || selfLoop))
                        {
                            //SCCCount++;
                            SCCTotalSize += SCCSize;

                            //System.Diagnostics.Debug.WriteLine(size);

                            // If forking condition is met, create new thread to process the SCC
                            if (SCCSize >= SCC_MINIMUM_SIZE_BOUND_FOR_THREAD_FORKING && ThreadPool.ThreadNumber < Ultility.Ultility.PARALLEL_MODEL_CHECKIMG_BOUND)
                            {
                                //System.Diagnostics.Debug.WriteLine("fork");
                                //BigSCCCount++;
                                Dictionary <string, LocalPair> SCC = new Dictionary <string, LocalPair>(SCCPairs);
                                StartFairThread(SCC);
                                //System.Diagnostics.Debug.WriteLine("(" + ThreadPool.ThreadNumber + ")");
                            }

                            // If the size of scc is small or the thread pool is full,
                            // process the SCC locally is more efficient
                            else
                            {
                                //System.Diagnostics.Debug.WriteLine("self");
                                Dictionary <string, LocalPair> value = IsFair(SCCPairs, OutgoingTransitionTable);
                                if (value != null)
                                {
                                    JobFinished        = true;
                                    VerificationResult = VerificationResultType.INVALID;
                                    FairSCC            = value;
                                    ThreadPool.StopAllThreads();
                                    return;
                                }
                            }
                        }

                        foreach (string componet in SCCPairs.Keys)
                        {
                            ExpendedNode.Remove(componet);
                            //BuchiFairTable.Remove(componet.ToString());

                            //OutgoingTransitionTable.Remove(componet);
                        }

                        SCCPairs = new Dictionary <string, LocalPair>(1024);
                    }
                    else
                    {
                        stepStack.Push(pair);
                    }
                }
            } while (TaskStack.Count > 0);

            JobFinished = true;

            return;
        }