OLD | NEW |
(Empty) | |
| 1 /* Copyright (c) 2014 The Chromium Authors. All rihts reserved. |
| 2 * Use of this source code is governed by a BSD-style license that can be |
| 3 * found in the LICENSE file. |
| 4 */ |
| 5 |
| 6 #ifndef WebWillBePrivateGarbageCollectedPtr_h |
| 7 #define WebWillBePrivateGarbageCollectedPtr_h |
| 8 |
| 9 #include "WebCommon.h" |
| 10 |
| 11 #if BLINK_IMPLEMENTATION |
| 12 #include "heap/Handle.h" |
| 13 #include "wtf/PassRefPtr.h" |
| 14 #endif |
| 15 |
| 16 namespace blink { |
| 17 |
| 18 // A variant of WebPrivatePtr that holds a Blink object that's garbage |
| 19 // collected, without exposing the details of how (and with what |
| 20 // types.) If no support for having such objects (i.e., Oilpan not |
| 21 // enabled), WebWillBePrivateGarbageCollectedPtr is equal to |
| 22 // WebPrivatePtr and the object will be reference counted. |
| 23 // |
| 24 // See WebPrivatePtr.h comment for how to make use of |
| 25 // WebWillBePrivateGarbageCollectedPtr; same pattern applies, but for |
| 26 // one detail. Instead of declaring & defining, |
| 27 // |
| 28 // #if BLINK_IMPLEMENTATION |
| 29 // WebFoo(const WTF::PassRefPtr<WebCore::Foo>&); |
| 30 // #endif |
| 31 // |
| 32 // provide |
| 33 // |
| 34 // #if BLINK_IMPLEMENTATION |
| 35 // WebFoo(const PassRefPtrWillBeRawPtr<WebCore::Foo>&); |
| 36 // #endif |
| 37 // |
| 38 template <typename T> |
| 39 class WebWillBePrivateGarbageCollectedPtr { |
| 40 public: |
| 41 WebWillBePrivateGarbageCollectedPtr() : m_ptr(0) { } |
| 42 ~WebWillBePrivateGarbageCollectedPtr() |
| 43 { |
| 44 // We don't destruct the object pointed by m_ptr here because we don't |
| 45 // want to expose destructors of core classes to embedders. We should |
| 46 // call reset() manually in destructors of classes with WebWillBePrivate
GarbageCollectedPtr |
| 47 // members. |
| 48 BLINK_ASSERT(!m_ptr); |
| 49 } |
| 50 |
| 51 bool isNull() const { return !m_ptr; } |
| 52 |
| 53 #if BLINK_IMPLEMENTATION |
| 54 #if ENABLE(OILPAN) |
| 55 WebWillBePrivateGarbageCollectedPtr(const PassRefPtrWillBeRawPtr<T>& p) |
| 56 { |
| 57 assign(p); |
| 58 } |
| 59 |
| 60 void reset() |
| 61 { |
| 62 if (m_ptr) { |
| 63 delete reinterpret_cast<WebCore::Persistent<T>*>(m_ptr); |
| 64 m_ptr = 0; |
| 65 } |
| 66 } |
| 67 |
| 68 WebWillBePrivateGarbageCollectedPtr<T>& operator=(const WebWillBePrivateGarb
ageCollectedPtr<T>& other) |
| 69 { |
| 70 assign(other.get()); |
| 71 return *this; |
| 72 } |
| 73 |
| 74 WebWillBePrivateGarbageCollectedPtr<T>& operator=(const PassRefPtrWillBeRawP
tr<T>& p) |
| 75 { |
| 76 assign(p); |
| 77 return *this; |
| 78 } |
| 79 |
| 80 T* get() const |
| 81 { |
| 82 if (!m_ptr) |
| 83 return 0; |
| 84 return (reinterpret_cast<WebCore::Persistent<T>* >(m_ptr))->get(); |
| 85 } |
| 86 |
| 87 T* operator->() const |
| 88 { |
| 89 ASSERT(m_ptr); |
| 90 return (reinterpret_cast<WebCore::Persistent<T>* >(m_ptr))->get(); |
| 91 } |
| 92 #else |
| 93 WebWillBePrivateGarbageCollectedPtr(const PassRefPtrWillBeRawPtr<T>& p) |
| 94 { |
| 95 m_ptr = p.leakRef(); |
| 96 } |
| 97 |
| 98 void reset() |
| 99 { |
| 100 assign(0); |
| 101 } |
| 102 |
| 103 WebWillBePrivateGarbageCollectedPtr<T>& operator=(const WebWillBePrivateGarb
ageCollectedPtr<T>& other) |
| 104 { |
| 105 T* p = other.m_ptr; |
| 106 if (p) |
| 107 p->ref(); |
| 108 assign(p); |
| 109 return *this; |
| 110 } |
| 111 |
| 112 WebWillBePrivateGarbageCollectedPtr<T>& operator=(const PassRefPtrWillBeRawP
tr<T>& p) |
| 113 { |
| 114 assign(p.leakRef()); |
| 115 return *this; |
| 116 } |
| 117 |
| 118 T* get() const |
| 119 { |
| 120 return m_ptr; |
| 121 } |
| 122 |
| 123 T* operator->() const |
| 124 { |
| 125 ASSERT(m_ptr); |
| 126 return m_ptr; |
| 127 } |
| 128 #endif |
| 129 #endif |
| 130 |
| 131 private: |
| 132 #if BLINK_IMPLEMENTATION |
| 133 #if ENABLE(OILPAN) |
| 134 void assign(T* p) |
| 135 { |
| 136 if (!p) { |
| 137 reset(); |
| 138 return; |
| 139 } |
| 140 // Keep an opaque object pointer to avoid exposing |
| 141 // representation details. |
| 142 if (!m_ptr) |
| 143 m_ptr = reinterpret_cast<T*>(new WebCore::Persistent<T>(p)); |
| 144 else |
| 145 *reinterpret_cast<WebCore::Persistent<T>*>(m_ptr) = p; |
| 146 } |
| 147 #else |
| 148 void assign(T* p) |
| 149 { |
| 150 // p is already ref'd for us by the caller |
| 151 if (m_ptr) |
| 152 m_ptr->deref(); |
| 153 m_ptr = p; |
| 154 } |
| 155 #endif |
| 156 #else |
| 157 // Disable the assignment operator; we define it above for when |
| 158 // BLINK_IMPLEMENTATION is set, but we need to make sure that it is not |
| 159 // used outside there; the compiler-provided version won't handle reference |
| 160 // counting properly. |
| 161 WebWillBePrivateGarbageCollectedPtr<T>& operator=(const WebWillBePrivateGarb
ageCollectedPtr<T>& other); |
| 162 #endif |
| 163 // Disable the copy constructor; classes that contain a |
| 164 // WebPrivateGarbageCollectedPtr should implement their copy |
| 165 // constructor using assign(). |
| 166 WebWillBePrivateGarbageCollectedPtr(const WebWillBePrivateGarbageCollectedPt
r<T>&); |
| 167 |
| 168 T* m_ptr; |
| 169 }; |
| 170 |
| 171 } // namespace blink |
| 172 |
| 173 #endif |
OLD | NEW |