C++: Do type and name equality checking in a safe manner.

Change the TypeMatcher to also match names, and use two "block" lists
in SafeMatcher to prevent infinite recursion.

Task-number: QTCREATORBUG-11240
Change-Id: I0367ae795ee6be579b83aeb8d46723c877e4aa75
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/libs/3rdparty/cplusplus/SafeMatcher.cpp

@@ -0,0 +1,160 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** 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, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "CoreTypes.h"
+#include "Names.h"
+#include "SafeMatcher.h"
+
+using namespace std;
+using namespace CPlusPlus;
+
+namespace {
+template<typename T>
+class Blocker
+{
+    vector<const T *> &v;
+
+public:
+    Blocker(vector<const T *> &v, const T *el1, const T *el2)
+        : v(v)
+    { v.push_back(el1); v.push_back(el2); }
+    ~Blocker() { v.pop_back(); v.pop_back(); }
+};
+
+template<typename T, typename U>
+bool isBlocked(const vector<const T *> &v, const U *t1, const U *t2)
+{
+    for (size_t i = v.size(); i > 0; ) {
+        const T *t = v[--i];
+        if (t == t1 || t == t2)
+            return true;
+    }
+
+    return false;
+}
+} // anonymous namespace
+
+SafeMatcher::SafeMatcher()
+{
+    _blockedTypes.reserve(8);
+    _blockedNames.reserve(8);
+}
+
+SafeMatcher::~SafeMatcher()
+{}
+
+bool SafeMatcher::match(const PointerToMemberType *type, const PointerToMemberType *otherType)
+{
+    if (isBlocked(_blockedTypes, type, otherType))
+        return true;
+
+    Blocker<Type> b(_blockedTypes, type, otherType);
+    return Matcher::match(type, otherType);
+}
+
+bool SafeMatcher::match(const PointerType *type, const PointerType *otherType)
+{
+    if (isBlocked(_blockedTypes, type, otherType))
+        return true;
+
+    Blocker<Type> b(_blockedTypes, type, otherType);
+    return Matcher::match(type, otherType);
+}
+
+bool SafeMatcher::match(const ReferenceType *type, const ReferenceType *otherType)
+{
+    if (isBlocked(_blockedTypes, type, otherType))
+        return true;
+
+    Blocker<Type> b(_blockedTypes, type, otherType);
+    return Matcher::match(type, otherType);
+}
+
+bool SafeMatcher::match(const ArrayType *type, const ArrayType *otherType)
+{
+    if (isBlocked(_blockedTypes, type, otherType))
+        return true;
+
+    Blocker<Type> b(_blockedTypes, type, otherType);
+    return Matcher::match(type, otherType);
+}
+
+bool SafeMatcher::match(const NamedType *type, const NamedType *otherType)
+{
+    if (isBlocked(_blockedTypes, type, otherType))
+        return true;
+
+    Blocker<Type> b(_blockedTypes, type, otherType);
+    return Matcher::match(type, otherType);
+}
+
+bool SafeMatcher::match(const TemplateNameId *name, const TemplateNameId *otherName)
+{
+    if (isBlocked(_blockedNames, name, otherName))
+        return true;
+
+    Blocker<Name> b(_blockedNames, name, otherName);
+    return Matcher::match(name, otherName);
+}
+
+bool SafeMatcher::match(const DestructorNameId *name, const DestructorNameId *otherName)
+{
+    if (isBlocked(_blockedNames, name, otherName))
+        return true;
+
+    Blocker<Name> b(_blockedNames, name, otherName);
+    return Matcher::match(name, otherName);
+}
+
+bool SafeMatcher::match(const ConversionNameId *name, const ConversionNameId *otherName)
+{
+    if (isBlocked(_blockedNames, name, otherName))
+        return true;
+
+    Blocker<Name> b(_blockedNames, name, otherName);
+    return Matcher::match(name, otherName);
+}
+
+bool SafeMatcher::match(const QualifiedNameId *name, const QualifiedNameId *otherName)
+{
+    if (isBlocked(_blockedNames, name, otherName))
+        return true;
+
+    Blocker<Name> b(_blockedNames, name, otherName);
+    return Matcher::match(name, otherName);
+}
+
+bool SafeMatcher::match(const SelectorNameId *name, const SelectorNameId *otherName)
+{
+    if (isBlocked(_blockedNames, name, otherName))
+        return true;
+
+    Blocker<Name> b(_blockedNames, name, otherName);
+    return Matcher::match(name, otherName);
+}