1 /* 2 * Copyright (C) 2009 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef SharedPersistent_h 32 #define SharedPersistent_h 33 34 #include <v8.h> 35 #include <wtf/PassRefPtr.h> 36 #include <wtf/RefCounted.h> 37 38 namespace WebCore { 39 40 // A shareable reference to a v8 persistent handle. Using a shared 41 // persistent any number of objects can share a reference to a v8 42 // object and when it should no longer be accessible the object's 43 // owner can clear it. 44 template <typename T> 45 class SharedPersistent : public RefCounted<SharedPersistent<T> > { 46 public: 47 void set(v8::Persistent<T> value) 48 { 49 m_value = value; 50 } 51 v8::Persistent<T> get() 52 { 53 return m_value; 54 } 55 void disposeHandle() 56 { 57 if (!m_value.IsEmpty()) { 58 m_value.Dispose(); 59 m_value.Clear(); 60 } 61 } 62 static PassRefPtr<SharedPersistent<T> > create(v8::Persistent<T> value) 63 { 64 return adoptRef(new SharedPersistent<T>(value)); 65 } 66 static PassRefPtr<SharedPersistent<T> > create() 67 { 68 return create(v8::Persistent<T>()); 69 } 70 private: 71 explicit SharedPersistent(v8::Persistent<T> value) : m_value(value) { } 72 v8::Persistent<T> m_value; 73 }; 74 75 } // namespace WebCore 76 77 #endif // SharedPersistent_h 78