// Copyright (C) 2000-2007, Luca Padovani <padovani@sti.uniurb.it>. // // This file is part of GtkMathView, a flexible, high-quality rendering // engine for MathML documents. // // GtkMathView is free software; you can redistribute it and/or modify it // under the terms of the GNU Lesser General Public License as published // by the Free Software Foundation; either version 3 of the License, or // (at your option) any later version. // // GtkMathView is distributed in the hope that it will be useful, but // WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public License // along with this program. If not, see <http://www.gnu.org/licenses/>. #ifndef __SmartPtr_hh__ #define __SmartPtr_hh__ #include <cassert> #include "gmv_defines.h" template <class P> class SmartPtr { public: SmartPtr(P* p = 0) : ptr(p) { if (ptr) ptr->ref(); } SmartPtr(const SmartPtr& p) : ptr(p.ptr) { if (ptr) ptr->ref(); } ~SmartPtr() { if (ptr) ptr->unref(); } P* operator->() const { assert(ptr); return ptr; } SmartPtr& operator=(const SmartPtr& p) { if (ptr == p.ptr) return *this; if (p.ptr) p.ptr->ref(); if (ptr) ptr->unref(); ptr = p.ptr; return *this; } operator P*() const { return ptr; } template <class Q, class R> friend SmartPtr<Q> smart_cast(const SmartPtr<R>&); template <class Q, class R> friend bool is_a(const SmartPtr<R>&); template <class Q> operator SmartPtr<Q>() const { return SmartPtr<Q>(ptr); } private: P* ptr; }; template <class Q, class P> SmartPtr<Q> smart_cast(const SmartPtr<P>& p) { return SmartPtr<Q>(dynamic_cast<Q*>(p.ptr)); } template <class Q, class R> bool is_a(const SmartPtr<R>& p) { return dynamic_cast<Q*>(p.ptr) != 0; } #endif // __SmartPtr_hh__