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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 127 insertions, 0 deletions

diff --git a/util/lexgen/nfa.h b/util/lexgen/nfa.h
new file mode 100644
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--- /dev/null
+++ b/util/lexgen/nfa.h
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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the utils 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.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef NFA_H
+#define NFA_H
+
+#include <QMap>
+#include <QHash>
+#include <QString>
+#include <QVector>
+#include <QDebug>
+#include <QStack>
+#include <QByteArray>
+
+#include "global.h"
+
+typedef QHash<InputType, int> TransitionMap;
+
+struct State
+{
+    QString symbol;
+    TransitionMap transitions;
+};
+
+inline QDataStream &operator<<(QDataStream &stream, const State &state)
+{
+    return stream << state.symbol << state.transitions;
+}
+
+inline QDataStream &operator>>(QDataStream &stream, State &state)
+{
+    return stream >> state.symbol >> state.transitions;
+}
+
+struct DFA : public QVector<State>
+{
+    void debug() const;
+    DFA minimize() const;
+};
+
+class NFA
+{
+public:
+    static NFA createSingleInputNFA(InputType input);
+    static NFA createSymbolNFA(const QString &symbol);
+    static NFA createAlternatingNFA(const NFA &a, const NFA &b);
+    static NFA createConcatenatingNFA(const NFA &a, const NFA &b);
+    static NFA createOptionalNFA(const NFA &a);
+
+    // convenience
+    static NFA createStringNFA(const QByteArray &str);
+    static NFA createSetNFA(const QSet<InputType> &set);
+    static NFA createZeroOrOneNFA(const NFA &a);
+    static NFA applyQuantity(const NFA &a, int minOccurrences, int maxOccurrences);
+
+    void setTerminationSymbol(const QString &symbol);
+    
+    DFA toDFA() const;
+
+    inline bool isEmpty() const { return states.isEmpty(); }
+    inline int stateCount() const { return states.count(); }
+
+    void debug();
+
+private:
+    void initialize(int size);
+    void addTransition(int from, InputType input, int to);
+    void copyFrom(const NFA &other, int baseState);
+
+    void initializeFromPair(const NFA &a, const NFA &b,
+                            int *initialA, int *finalA,
+                            int *initialB, int *finalB);
+
+    QSet<int> epsilonClosure(const QSet<int> &initialClosure) const;
+
+    inline void assertValidState(int state)
+    { Q_UNUSED(state); Q_ASSERT(state >= 0); Q_ASSERT(state < states.count()); }
+    
+#if defined(AUTOTEST)
+public:
+#endif
+    int initialState;
+    int finalState;
+
+    QVector<State> states;
+};
+
+#endif // NFA_H
+