michael@0: /*
michael@0:  * Copyright (C) 2005 The Android Open Source Project
michael@0:  *
michael@0:  * Licensed under the Apache License, Version 2.0 (the "License");
michael@0:  * you may not use this file except in compliance with the License.
michael@0:  * You may obtain a copy of the License at
michael@0:  *
michael@0:  *      http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing, software
michael@0:  * distributed under the License is distributed on an "AS IS" BASIS,
michael@0:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
michael@0:  * See the License for the specific language governing permissions and
michael@0:  * limitations under the License.
michael@0:  */
michael@0: 
michael@0: #ifndef ANDROID_STRONG_POINTER_H
michael@0: #define ANDROID_STRONG_POINTER_H
michael@0: 
michael@0: #include <cutils/atomic.h>
michael@0: 
michael@0: #include <stdint.h>
michael@0: #include <sys/types.h>
michael@0: #include <stdlib.h>
michael@0: 
michael@0: // ---------------------------------------------------------------------------
michael@0: namespace android {
michael@0: 
michael@0: class TextOutput;
michael@0: TextOutput& printStrongPointer(TextOutput& to, const void* val);
michael@0: 
michael@0: template<typename T> class wp;
michael@0: 
michael@0: // ---------------------------------------------------------------------------
michael@0: 
michael@0: #define COMPARE(_op_)                                           \
michael@0: inline bool operator _op_ (const sp<T>& o) const {              \
michael@0:     return m_ptr _op_ o.m_ptr;                                  \
michael@0: }                                                               \
michael@0: inline bool operator _op_ (const T* o) const {                  \
michael@0:     return m_ptr _op_ o;                                        \
michael@0: }                                                               \
michael@0: template<typename U>                                            \
michael@0: inline bool operator _op_ (const sp<U>& o) const {              \
michael@0:     return m_ptr _op_ o.m_ptr;                                  \
michael@0: }                                                               \
michael@0: template<typename U>                                            \
michael@0: inline bool operator _op_ (const U* o) const {                  \
michael@0:     return m_ptr _op_ o;                                        \
michael@0: }                                                               \
michael@0: inline bool operator _op_ (const wp<T>& o) const {              \
michael@0:     return m_ptr _op_ o.m_ptr;                                  \
michael@0: }                                                               \
michael@0: template<typename U>                                            \
michael@0: inline bool operator _op_ (const wp<U>& o) const {              \
michael@0:     return m_ptr _op_ o.m_ptr;                                  \
michael@0: }
michael@0: 
michael@0: // ---------------------------------------------------------------------------
michael@0: 
michael@0: template <typename T>
michael@0: class sp
michael@0: {
michael@0: public:
michael@0:     inline sp() : m_ptr(0) { }
michael@0: 
michael@0:     sp(T* other);
michael@0:     sp(const sp<T>& other);
michael@0:     template<typename U> sp(U* other);
michael@0:     template<typename U> sp(const sp<U>& other);
michael@0: 
michael@0:     ~sp();
michael@0: 
michael@0:     // Assignment
michael@0: 
michael@0:     sp& operator = (T* other);
michael@0:     sp& operator = (const sp<T>& other);
michael@0: 
michael@0:     template<typename U> sp& operator = (const sp<U>& other);
michael@0:     template<typename U> sp& operator = (U* other);
michael@0: 
michael@0:     //! Special optimization for use by ProcessState (and nobody else).
michael@0:     void force_set(T* other);
michael@0: 
michael@0:     // Reset
michael@0: 
michael@0:     void clear();
michael@0: 
michael@0:     // Accessors
michael@0: 
michael@0:     inline  T&      operator* () const  { return *m_ptr; }
michael@0:     inline  T*      operator-> () const { return m_ptr;  }
michael@0:     inline  T*      get() const         { return m_ptr; }
michael@0: 
michael@0:     // Operators
michael@0: 
michael@0:     COMPARE(==)
michael@0:     COMPARE(!=)
michael@0:     COMPARE(>)
michael@0:     COMPARE(<)
michael@0:     COMPARE(<=)
michael@0:     COMPARE(>=)
michael@0: 
michael@0: private:    
michael@0:     template<typename Y> friend class sp;
michael@0:     template<typename Y> friend class wp;
michael@0:     void set_pointer(T* ptr);
michael@0:     T* m_ptr;
michael@0: };
michael@0: 
michael@0: #undef COMPARE
michael@0: 
michael@0: template <typename T>
michael@0: TextOutput& operator<<(TextOutput& to, const sp<T>& val);
michael@0: 
michael@0: // ---------------------------------------------------------------------------
michael@0: // No user serviceable parts below here.
michael@0: 
michael@0: template<typename T>
michael@0: sp<T>::sp(T* other)
michael@0: : m_ptr(other)
michael@0:   {
michael@0:     if (other) other->incStrong(this);
michael@0:   }
michael@0: 
michael@0: template<typename T>
michael@0: sp<T>::sp(const sp<T>& other)
michael@0: : m_ptr(other.m_ptr)
michael@0:   {
michael@0:     if (m_ptr) m_ptr->incStrong(this);
michael@0:   }
michael@0: 
michael@0: template<typename T> template<typename U>
michael@0: sp<T>::sp(U* other) : m_ptr(other)
michael@0: {
michael@0:     if (other) ((T*)other)->incStrong(this);
michael@0: }
michael@0: 
michael@0: template<typename T> template<typename U>
michael@0: sp<T>::sp(const sp<U>& other)
michael@0: : m_ptr(other.m_ptr)
michael@0:   {
michael@0:     if (m_ptr) m_ptr->incStrong(this);
michael@0:   }
michael@0: 
michael@0: template<typename T>
michael@0: sp<T>::~sp()
michael@0: {
michael@0:     if (m_ptr) m_ptr->decStrong(this);
michael@0: }
michael@0: 
michael@0: template<typename T>
michael@0: sp<T>& sp<T>::operator = (const sp<T>& other) {
michael@0:     T* otherPtr(other.m_ptr);
michael@0:     if (otherPtr) otherPtr->incStrong(this);
michael@0:     if (m_ptr) m_ptr->decStrong(this);
michael@0:     m_ptr = otherPtr;
michael@0:     return *this;
michael@0: }
michael@0: 
michael@0: template<typename T>
michael@0: sp<T>& sp<T>::operator = (T* other)
michael@0: {
michael@0:     if (other) other->incStrong(this);
michael@0:     if (m_ptr) m_ptr->decStrong(this);
michael@0:     m_ptr = other;
michael@0:     return *this;
michael@0: }
michael@0: 
michael@0: template<typename T> template<typename U>
michael@0: sp<T>& sp<T>::operator = (const sp<U>& other)
michael@0: {
michael@0:     T* otherPtr(other.m_ptr);
michael@0:     if (otherPtr) otherPtr->incStrong(this);
michael@0:     if (m_ptr) m_ptr->decStrong(this);
michael@0:     m_ptr = otherPtr;
michael@0:     return *this;
michael@0: }
michael@0: 
michael@0: template<typename T> template<typename U>
michael@0: sp<T>& sp<T>::operator = (U* other)
michael@0: {
michael@0:     if (other) ((T*)other)->incStrong(this);
michael@0:     if (m_ptr) m_ptr->decStrong(this);
michael@0:     m_ptr = other;
michael@0:     return *this;
michael@0: }
michael@0: 
michael@0: template<typename T>    
michael@0: void sp<T>::force_set(T* other)
michael@0: {
michael@0:     other->forceIncStrong(this);
michael@0:     m_ptr = other;
michael@0: }
michael@0: 
michael@0: template<typename T>
michael@0: void sp<T>::clear()
michael@0: {
michael@0:     if (m_ptr) {
michael@0:         m_ptr->decStrong(this);
michael@0:         m_ptr = 0;
michael@0:     }
michael@0: }
michael@0: 
michael@0: template<typename T>
michael@0: void sp<T>::set_pointer(T* ptr) {
michael@0:     m_ptr = ptr;
michael@0: }
michael@0: 
michael@0: template <typename T>
michael@0: inline TextOutput& operator<<(TextOutput& to, const sp<T>& val)
michael@0: {
michael@0:     return printStrongPointer(to, val.get());
michael@0: }
michael@0: 
michael@0: }; // namespace android
michael@0: 
michael@0: // ---------------------------------------------------------------------------
michael@0: 
michael@0: #endif // ANDROID_STRONG_POINTER_H