1 /* 2 * Copyright (C) 2005, 2006, 2008 Apple Inc. All rights reserved. 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Library General Public 6 * License as published by the Free Software Foundation; either 7 * version 2 of the License, or (at your option) any later version. 8 * 9 * This library is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Library General Public License for more details. 13 * 14 * You should have received a copy of the GNU Library General Public License 15 * along with this library; see the file COPYING.LIB. If not, write to 16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 17 * Boston, MA 02110-1301, USA. 18 * 19 */ 20 21 #ifndef WTF_ListRefPtr_h 22 #define WTF_ListRefPtr_h 23 24 #include <wtf/RefPtr.h> 25 26 namespace WTF { 27 28 // Specialized version of RefPtr desgined for use in singly-linked lists. 29 // Derefs the list iteratively to avoid recursive derefing that can overflow the stack. 30 template <typename T> class ListRefPtr : public RefPtr<T> { 31 public: 32 ListRefPtr() : RefPtr<T>() {} 33 ListRefPtr(T* ptr) : RefPtr<T>(ptr) {} 34 ListRefPtr(const RefPtr<T>& o) : RefPtr<T>(o) {} 35 // see comment in PassRefPtr.h for why this takes const reference 36 template <typename U> ListRefPtr(const PassRefPtr<U>& o) : RefPtr<T>(o) {} 37 38 ~ListRefPtr(); 39 40 ListRefPtr& operator=(T* optr) { RefPtr<T>::operator=(optr); return *this; } 41 ListRefPtr& operator=(const RefPtr<T>& o) { RefPtr<T>::operator=(o); return *this; } 42 ListRefPtr& operator=(const PassRefPtr<T>& o) { RefPtr<T>::operator=(o); return *this; } 43 template <typename U> ListRefPtr& operator=(const RefPtr<U>& o) { RefPtr<T>::operator=(o); return *this; } 44 template <typename U> ListRefPtr& operator=(const PassRefPtr<U>& o) { RefPtr<T>::operator=(o); return *this; } 45 }; 46 47 // Remove inline for winscw compiler to prevent the compiler agressively resolving 48 // T::ref() in RefPtr<T>'s copy constructor. The bug is reported at: 49 // https://xdabug001.ext.nokia.com/bugzilla/show_bug.cgi?id=9812. 50 template <typename T> 51 #if !COMPILER(WINSCW) 52 inline 53 #endif 54 ListRefPtr<T>::~ListRefPtr() 55 { 56 RefPtr<T> reaper = this->release(); 57 while (reaper && reaper->hasOneRef()) 58 reaper = reaper->releaseNext(); // implicitly protects reaper->next, then derefs reaper 59 } 60 61 template <typename T> inline T* getPtr(const ListRefPtr<T>& p) 62 { 63 return p.get(); 64 } 65 66 } // namespace WTF 67 68 using WTF::ListRefPtr; 69 70 #endif // WTF_ListRefPtr_h 71
