1 /* 2 * Copyright (C) 2000 Lars Knoll (knoll (at) kde.org) 3 * (C) 2000 Antti Koivisto (koivisto (at) kde.org) 4 * (C) 2000 Dirk Mueller (mueller (at) kde.org) 5 * Copyright (C) 2003, 2005, 2008 Apple Inc. All rights reserved. 6 * 7 * This library is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Library General Public 9 * License as published by the Free Software Foundation; either 10 * version 2 of the License, or (at your option) any later version. 11 * 12 * This library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Library General Public License for more details. 16 * 17 * You should have received a copy of the GNU Library General Public License 18 * along with this library; see the file COPYING.LIB. If not, write to 19 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 20 * Boston, MA 02110-1301, USA. 21 * 22 */ 23 24 #ifndef DataRef_h 25 #define DataRef_h 26 27 #include <wtf/RefPtr.h> 28 29 namespace WebCore { 30 31 template <typename T> class DataRef { 32 public: 33 const T* get() const { return m_data.get(); } 34 35 const T& operator*() const { return *get(); } 36 const T* operator->() const { return get(); } 37 38 T* access() 39 { 40 if (!m_data->hasOneRef()) 41 m_data = m_data->copy(); 42 return m_data.get(); 43 } 44 45 void init() 46 { 47 ASSERT(!m_data); 48 m_data = T::create(); 49 } 50 51 bool operator==(const DataRef<T>& o) const 52 { 53 ASSERT(m_data); 54 ASSERT(o.m_data); 55 return m_data == o.m_data || *m_data == *o.m_data; 56 } 57 58 bool operator!=(const DataRef<T>& o) const 59 { 60 ASSERT(m_data); 61 ASSERT(o.m_data); 62 return m_data != o.m_data && *m_data != *o.m_data; 63 } 64 65 private: 66 RefPtr<T> m_data; 67 }; 68 69 } // namespace WebCore 70 71 #endif // DataRef_h 72