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+/****************************************************************************
+**
+** Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtXmlPatterns module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*
+ * NOTE: This file is included by qxsdstatemachine_p.h
+ * if you need some includes, put them in qxsdstatemachine_p.h (outside of the namespace)
+ */
+
+template <typename TransitionType>
+XsdStateMachine<TransitionType>::XsdStateMachine()
+ : m_counter(50)
+{
+}
+
+template <typename TransitionType>
+XsdStateMachine<TransitionType>::XsdStateMachine(const NamePool::Ptr &namePool)
+ : m_namePool(namePool)
+ , m_counter(50)
+{
+}
+
+template <typename TransitionType>
+typename XsdStateMachine<TransitionType>::StateId XsdStateMachine<TransitionType>::addState(StateType type)
+{
+#ifndef QT_NO_DEBUG
+ // make sure we don't have two start states
+ if (type == StartState) {
+ QHashIterator<StateId, StateType> it(m_states);
+ while (it.hasNext()) {
+ it.next();
+ Q_ASSERT(it.value() != StartState && it.value() != StartEndState);
+ }
+ }
+#endif // QT_NO_DEBUG
+
+ // reserve new state id
+ const StateId id = ++m_counter;
+ m_states.insert(id, type);
+
+ // if it is a start state, we make it to our current state
+ if (type == StartState || type == StartEndState)
+ m_currentState = id;
+
+ return id;
+}
+
+template <typename TransitionType>
+void XsdStateMachine<TransitionType>::addTransition(StateId start, TransitionType transition, StateId end)
+{
+ QHash<TransitionType, QVector<StateId> > &hash = m_transitions[start];
+ QVector<StateId> &states = hash[transition];
+ if (!states.contains(end))
+ states.append(end);
+}
+
+template <typename TransitionType>
+void XsdStateMachine<TransitionType>::addEpsilonTransition(StateId start, StateId end)
+{
+ QVector<StateId> &states = m_epsilonTransitions[start];
+ states.append(end);
+}
+
+template <typename TransitionType>
+void XsdStateMachine<TransitionType>::reset()
+{
+ // reset the machine to the start state
+ QHashIterator<StateId, StateType> it(m_states);
+ while (it.hasNext()) {
+ it.next();
+ if (it.value() == StartState || it.value() == StartEndState) {
+ m_currentState = it.key();
+ return;
+ }
+ }
+
+ Q_ASSERT(false);
+}
+
+template <typename TransitionType>
+void XsdStateMachine<TransitionType>::clear()
+{
+ m_states.clear();
+ m_transitions.clear();
+ m_epsilonTransitions.clear();
+ m_currentState = -1;
+ m_counter = 50;
+}
+
+template <typename TransitionType>
+bool XsdStateMachine<TransitionType>::proceed(TransitionType transition)
+{
+ // check that we are not in an invalid state
+ if (!m_transitions.contains(m_currentState)) {
+ return false;
+ }
+
+ // fetch the transition entry for the current state
+ const QHash<TransitionType, QVector<StateId> > &entry = m_transitions[m_currentState];
+ if (entry.contains(transition)) { // is there an transition for the given input?
+ m_currentState = entry.value(transition).first();
+ m_lastTransition = transition;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+template <typename TransitionType>
+QList<TransitionType> XsdStateMachine<TransitionType>::possibleTransitions() const
+{
+ // check that we are not in an invalid state
+ if (!m_transitions.contains(m_currentState)) {
+ return QList<TransitionType>();
+ }
+
+ // fetch the transition entry for the current state
+ const QHash<TransitionType, QVector<StateId> > &entry = m_transitions[m_currentState];
+
+ return entry.keys();
+}
+
+template <typename TransitionType>
+template <typename InputType>
+bool XsdStateMachine<TransitionType>::proceed(InputType input)
+{
+ // check that we are not in an invalid state
+ if (!m_transitions.contains(m_currentState)) {
+ return false;
+ }
+
+ // fetch the transition entry for the current state
+ const QHash<TransitionType, QVector<StateId> > &entry = m_transitions[m_currentState];
+ QHashIterator<TransitionType, QVector<StateId> > it(entry);
+ while (it.hasNext()) {
+ it.next();
+ if (inputEqualsTransition(input, it.key())) {
+ m_currentState = it.value().first();
+ m_lastTransition = it.key();
+ return true;
+ }
+ }
+
+ return false;
+}
+
+template <typename TransitionType>
+template <typename InputType>
+bool XsdStateMachine<TransitionType>::inputEqualsTransition(InputType input, TransitionType transition) const
+{
+ return false;
+}
+
+template <typename TransitionType>
+bool XsdStateMachine<TransitionType>::inEndState() const
+{
+ // check if current state is an end state
+ return (m_states.value(m_currentState) == StartEndState || m_states.value(m_currentState) == EndState);
+}
+
+template <typename TransitionType>
+TransitionType XsdStateMachine<TransitionType>::lastTransition() const
+{
+ return m_lastTransition;
+}
+
+template <typename TransitionType>
+typename XsdStateMachine<TransitionType>::StateId XsdStateMachine<TransitionType>::startState() const
+{
+ QHashIterator<StateId, StateType> it(m_states);
+ while (it.hasNext()) {
+ it.next();
+ if (it.value() == StartState || it.value() == StartEndState)
+ return it.key();
+ }
+
+ Q_ASSERT(false); // should never be reached
+ return -1;
+}
+
+template <typename TransitionType>
+QString XsdStateMachine<TransitionType>::transitionTypeToString(TransitionType type) const
+{
+ Q_UNUSED(type)
+
+ return QString();
+}
+
+template <typename TransitionType>
+bool XsdStateMachine<TransitionType>::outputGraph(QIODevice *device, const QString &graphName) const
+{
+ if (!device->isOpen()) {
+ qWarning("device must be open for writing");
+ return false;
+ }
+
+ QByteArray graph;
+ QTextStream s(&graph);
+
+ QHashIterator<StateId, QHash<TransitionType, QVector<StateId> > > it(m_transitions);
+ QHashIterator<StateId, StateType> it3(m_states);
+
+ s << "digraph " << graphName << " {\n";
+ s << " mindist = 2.0\n";
+
+ // draw edges
+ while (it.hasNext()) {
+ it.next();
+
+ QHashIterator<TransitionType, QVector<StateId> > it2(it.value());
+ while (it2.hasNext()) {
+ it2.next();
+ for (int i = 0; i < it2.value().count(); ++i)
+ s << " " << it.key() << " -> " << it2.value().at(i) << " [label=\"" << transitionTypeToString(it2.key()) << "\"]\n";
+ }
+ }
+
+ QHashIterator<StateId, QVector<StateId> > it4(m_epsilonTransitions);
+ while (it4.hasNext()) {
+ it4.next();
+
+ const QVector<StateId> states = it4.value();
+ for (int i = 0; i < states.count(); ++i)
+ s << " " << it4.key() << " -> " << states.at(i) << " [label=\"&#949;\"]\n";
+ }
+
+ // draw node infos
+ while (it3.hasNext()) {
+ it3.next();
+
+ QString style;
+ if (it3.value() == StartState) {
+ style = QLatin1String("shape=circle, style=filled, color=blue");
+ } else if (it3.value() == StartEndState) {
+ style = QLatin1String("shape=doublecircle, style=filled, color=blue");
+ } else if (it3.value() == InternalState) {
+ style = QLatin1String("shape=circle, style=filled, color=red");
+ } else if (it3.value() == EndState) {
+ style = QLatin1String("shape=doublecircle, style=filled, color=green");
+ }
+
+ s << " " << it3.key() << " [" << style << "]\n";
+ }
+
+ s << "}\n";
+
+ s.flush();
+
+ if (device->write(graph) == -1)
+ return false;
+
+ return true;
+}
+
+
+template <typename TransitionType>
+typename XsdStateMachine<TransitionType>::StateId XsdStateMachine<TransitionType>::dfaStateForNfaState(QSet<StateId> nfaState,
+ QList< QPair<QSet<StateId>, StateId> > &stateTable,
+ XsdStateMachine<TransitionType> &dfa) const
+{
+ // check whether we have the given state in our lookup table
+ // already, in that case simply return it
+ for (int i = 0; i < stateTable.count(); ++i) {
+ if (stateTable.at(i).first == nfaState)
+ return stateTable.at(i).second;
+ }
+
+ // check if the NFA state set contains a Start or End
+ // state, in that case our new DFA state will be a
+ // Start or End state as well
+ StateType type = InternalState;
+ QSetIterator<StateId> it(nfaState);
+ bool hasStartState = false;
+ bool hasEndState = false;
+ while (it.hasNext()) {
+ const StateId state = it.next();
+ if (m_states.value(state) == EndState) {
+ hasEndState = true;
+ } else if (m_states.value(state) == StartState) {
+ hasStartState = true;
+ }
+ }
+ if (hasStartState) {
+ if (hasEndState)
+ type = StartEndState;
+ else
+ type = StartState;
+ } else if (hasEndState) {
+ type = EndState;
+ }
+
+ // create the new DFA state
+ const StateId dfaState = dfa.addState(type);
+
+ // add the new DFA state to the lookup table
+ stateTable.append(qMakePair<QSet<StateId>, StateId>(nfaState, dfaState));
+
+ return dfaState;
+}
+
+template <typename TransitionType>
+XsdStateMachine<TransitionType> XsdStateMachine<TransitionType>::toDFA() const
+{
+ XsdStateMachine<TransitionType> dfa(m_namePool);
+ dfa.m_counter = 100;
+ QList< QPair< QSet<StateId>, StateId> > table;
+ QList< QSet<StateId> > isMarked;
+
+ // search the start state as the algorithm starts with it...
+ StateId startState = -1;
+ QHashIterator<StateId, StateType> stateTypeIt(m_states);
+ while (stateTypeIt.hasNext()) {
+ stateTypeIt.next();
+ if (stateTypeIt.value() == StartState) {
+ startState = stateTypeIt.key();
+ break;
+ }
+ }
+ Q_ASSERT(startState != -1);
+
+ // our list of state set that still have to be processed
+ QList< QSet<StateId> > workStates;
+
+ // add the start state to the list of to processed state sets
+ workStates.append(epsilonClosure(QSet<StateId>() << startState));
+
+ while (!workStates.isEmpty()) { // as long as there are state sets to process left
+
+ // enqueue set of states
+ const QSet<StateId> states = workStates.takeFirst();
+
+ if (isMarked.contains(states)) // we processed this state set already
+ continue;
+
+ // mark as processed
+ isMarked.append(states);
+
+ // select a list of all inputs that are possible for
+ // the 'states' set
+ QList<TransitionType> input;
+
+ {
+ QSetIterator<StateId> it(states);
+ while (it.hasNext()) {
+ input << m_transitions.value(it.next()).keys();
+ }
+ }
+
+ // get the state in DFA that corresponds to the 'states' set in the NFA
+ const StateId dfaBegin = dfaStateForNfaState(states, table, dfa);
+
+ for (int i = 0; i < input.count(); ++i) { // for each possible input
+ // retrieve the states that can be reached from the 'states' set by the
+ // given input or by epsilon transition
+ const QSet<StateId> followStates = epsilonClosure(move(states, input.at(i)));
+
+ // get the state in DFA that corresponds to the 'followStates' set in the NFA
+ const StateId dfaEnd = dfaStateForNfaState(followStates, table, dfa);
+
+ // adds a new transition to the DFA that corresponds to the transitions between
+ // 'states' and 'followStates' in the NFA
+ dfa.addTransition(dfaBegin, input.at(i), dfaEnd);
+
+ // add the 'followStates' to the list of to be processed state sets
+ workStates.append(followStates);
+ }
+ }
+
+ return dfa;
+}
+
+template <typename TransitionType>
+QHash<typename XsdStateMachine<TransitionType>::StateId, typename XsdStateMachine<TransitionType>::StateType> XsdStateMachine<TransitionType>::states() const
+{
+ return m_states;
+}