1 /* 2 * Copyright (C) 2008 Apple 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 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef ResourcePtr_h 27 #define ResourcePtr_h 28 29 #include "core/loader/cache/Resource.h" 30 31 namespace WebCore { 32 33 class ResourcePtrBase { 34 public: 35 ~ResourcePtrBase(); 36 37 Resource* get() const { return m_resource; } 38 bool operator!() const { return !m_resource; } 39 40 // This conversion operator allows implicit conversion to bool but not to other integer types. 41 typedef Resource* ResourcePtrBase::*UnspecifiedBoolType; 42 operator UnspecifiedBoolType() const { return m_resource ? &ResourcePtrBase::m_resource : 0; } 43 44 protected: 45 ResourcePtrBase() : m_resource(0) { } 46 ResourcePtrBase(Resource*); 47 ResourcePtrBase(const ResourcePtrBase&); 48 49 void setResource(Resource*); 50 51 private: 52 ResourcePtrBase& operator=(const ResourcePtrBase&) { return *this; } 53 54 friend class Resource; 55 56 Resource* m_resource; 57 }; 58 59 inline ResourcePtrBase::ResourcePtrBase(Resource* res) 60 : m_resource(res) 61 { 62 if (m_resource) 63 m_resource->registerHandle(this); 64 } 65 66 inline ResourcePtrBase::~ResourcePtrBase() 67 { 68 if (m_resource) 69 m_resource->unregisterHandle(this); 70 } 71 72 inline ResourcePtrBase::ResourcePtrBase(const ResourcePtrBase& o) 73 : m_resource(o.m_resource) 74 { 75 if (m_resource) 76 m_resource->registerHandle(this); 77 } 78 79 template <class R> class ResourcePtr : public ResourcePtrBase { 80 public: 81 ResourcePtr() { } 82 ResourcePtr(R* res) : ResourcePtrBase(res) { } 83 ResourcePtr(const ResourcePtr<R>& o) : ResourcePtrBase(o) { } 84 template<typename U> ResourcePtr(const ResourcePtr<U>& o) : ResourcePtrBase(o.get()) { } 85 86 R* get() const { return reinterpret_cast<R*>(ResourcePtrBase::get()); } 87 R* operator->() const { return get(); } 88 89 ResourcePtr& operator=(R* res) { setResource(res); return *this; } 90 ResourcePtr& operator=(const ResourcePtr& o) { setResource(o.get()); return *this; } 91 template<typename U> ResourcePtr& operator=(const ResourcePtr<U>& o) { setResource(o.get()); return *this; } 92 93 bool operator==(const ResourcePtrBase& o) const { return get() == o.get(); } 94 bool operator!=(const ResourcePtrBase& o) const { return get() != o.get(); } 95 }; 96 97 template <class R, class RR> bool operator==(const ResourcePtr<R>& h, const RR* res) 98 { 99 return h.get() == res; 100 } 101 template <class R, class RR> bool operator==(const RR* res, const ResourcePtr<R>& h) 102 { 103 return h.get() == res; 104 } 105 template <class R, class RR> bool operator!=(const ResourcePtr<R>& h, const RR* res) 106 { 107 return h.get() != res; 108 } 109 template <class R, class RR> bool operator!=(const RR* res, const ResourcePtr<R>& h) 110 { 111 return h.get() != res; 112 } 113 } 114 115 #endif 116