| /* |
| * Copyright (C) 2005 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ANDROID_STRONG_POINTER_H |
| #define ANDROID_STRONG_POINTER_H |
| |
| // --------------------------------------------------------------------------- |
| namespace android { |
| |
| template<typename T> class wp; |
| |
| // --------------------------------------------------------------------------- |
| |
| #define COMPARE(_op_) \ |
| inline bool operator _op_ (const sp<T>& o) const { \ |
| return m_ptr _op_ o.m_ptr; \ |
| } \ |
| inline bool operator _op_ (const T* o) const { \ |
| return m_ptr _op_ o; \ |
| } \ |
| template<typename U> \ |
| inline bool operator _op_ (const sp<U>& o) const { \ |
| return m_ptr _op_ o.m_ptr; \ |
| } \ |
| template<typename U> \ |
| inline bool operator _op_ (const U* o) const { \ |
| return m_ptr _op_ o; \ |
| } \ |
| inline bool operator _op_ (const wp<T>& o) const { \ |
| return m_ptr _op_ o.m_ptr; \ |
| } \ |
| template<typename U> \ |
| inline bool operator _op_ (const wp<U>& o) const { \ |
| return m_ptr _op_ o.m_ptr; \ |
| } |
| |
| // --------------------------------------------------------------------------- |
| |
| template<typename T> |
| class sp { |
| public: |
| inline sp() : m_ptr(nullptr) { } |
| |
| sp(T* other); // NOLINT(implicit) |
| sp(const sp<T>& other); |
| sp(sp<T>&& other) noexcept; |
| template<typename U> sp(U* other); // NOLINT(implicit) |
| template<typename U> sp(const sp<U>& other); // NOLINT(implicit) |
| template<typename U> sp(sp<U>&& other); // NOLINT(implicit) |
| |
| ~sp(); |
| |
| // Assignment |
| |
| sp& operator = (T* other); |
| sp& operator = (const sp<T>& other); |
| sp& operator=(sp<T>&& other) noexcept; |
| |
| template<typename U> sp& operator = (const sp<U>& other); |
| template<typename U> sp& operator = (sp<U>&& other); |
| template<typename U> sp& operator = (U* other); |
| |
| //! Special optimization for use by ProcessState (and nobody else). |
| void force_set(T* other); |
| |
| // Reset |
| |
| void clear(); |
| |
| // Accessors |
| |
| inline T& operator* () const { return *m_ptr; } |
| inline T* operator-> () const { return m_ptr; } |
| inline T* get() const { return m_ptr; } |
| inline explicit operator bool () const { return m_ptr != nullptr; } |
| |
| // Operators |
| |
| COMPARE(==) |
| COMPARE(!=) |
| COMPARE(>) |
| COMPARE(<) |
| COMPARE(<=) |
| COMPARE(>=) |
| |
| private: |
| template<typename Y> friend class sp; |
| template<typename Y> friend class wp; |
| void set_pointer(T* ptr); |
| T* m_ptr; |
| }; |
| |
| // For code size reasons, we do not want this inlined or templated. |
| void sp_report_race(); |
| |
| #undef COMPARE |
| |
| // --------------------------------------------------------------------------- |
| // No user serviceable parts below here. |
| |
| template<typename T> |
| sp<T>::sp(T* other) |
| : m_ptr(other) { |
| if (other) |
| other->incStrong(this); |
| } |
| |
| template<typename T> |
| sp<T>::sp(const sp<T>& other) |
| : m_ptr(other.m_ptr) { |
| if (m_ptr) |
| m_ptr->incStrong(this); |
| } |
| |
| template <typename T> |
| sp<T>::sp(sp<T>&& other) noexcept : m_ptr(other.m_ptr) { |
| other.m_ptr = nullptr; |
| } |
| |
| template<typename T> template<typename U> |
| sp<T>::sp(U* other) |
| : m_ptr(other) { |
| if (other) |
| (static_cast<T*>(other))->incStrong(this); |
| } |
| |
| template<typename T> template<typename U> |
| sp<T>::sp(const sp<U>& other) |
| : m_ptr(other.m_ptr) { |
| if (m_ptr) |
| m_ptr->incStrong(this); |
| } |
| |
| template<typename T> template<typename U> |
| sp<T>::sp(sp<U>&& other) |
| : m_ptr(other.m_ptr) { |
| other.m_ptr = nullptr; |
| } |
| |
| template<typename T> |
| sp<T>::~sp() { |
| if (m_ptr) |
| m_ptr->decStrong(this); |
| } |
| |
| template<typename T> |
| sp<T>& sp<T>::operator =(const sp<T>& other) { |
| // Force m_ptr to be read twice, to heuristically check for data races. |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| T* otherPtr(other.m_ptr); |
| if (otherPtr) otherPtr->incStrong(this); |
| if (oldPtr) oldPtr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = otherPtr; |
| return *this; |
| } |
| |
| template <typename T> |
| sp<T>& sp<T>::operator=(sp<T>&& other) noexcept { |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| if (oldPtr) oldPtr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = other.m_ptr; |
| other.m_ptr = nullptr; |
| return *this; |
| } |
| |
| template<typename T> |
| sp<T>& sp<T>::operator =(T* other) { |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| if (other) other->incStrong(this); |
| if (oldPtr) oldPtr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = other; |
| return *this; |
| } |
| |
| template<typename T> template<typename U> |
| sp<T>& sp<T>::operator =(const sp<U>& other) { |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| T* otherPtr(other.m_ptr); |
| if (otherPtr) otherPtr->incStrong(this); |
| if (oldPtr) oldPtr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = otherPtr; |
| return *this; |
| } |
| |
| template<typename T> template<typename U> |
| sp<T>& sp<T>::operator =(sp<U>&& other) { |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| if (m_ptr) m_ptr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = other.m_ptr; |
| other.m_ptr = nullptr; |
| return *this; |
| } |
| |
| template<typename T> template<typename U> |
| sp<T>& sp<T>::operator =(U* other) { |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| if (other) (static_cast<T*>(other))->incStrong(this); |
| if (oldPtr) oldPtr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = other; |
| return *this; |
| } |
| |
| template<typename T> |
| void sp<T>::force_set(T* other) { |
| other->forceIncStrong(this); |
| m_ptr = other; |
| } |
| |
| template<typename T> |
| void sp<T>::clear() { |
| T* oldPtr(*const_cast<T* volatile*>(&m_ptr)); |
| if (oldPtr) { |
| oldPtr->decStrong(this); |
| if (oldPtr != *const_cast<T* volatile*>(&m_ptr)) sp_report_race(); |
| m_ptr = nullptr; |
| } |
| } |
| |
| template<typename T> |
| void sp<T>::set_pointer(T* ptr) { |
| m_ptr = ptr; |
| } |
| |
| } // namespace android |
| |
| // --------------------------------------------------------------------------- |
| |
| #endif // ANDROID_STRONG_POINTER_H |