1 /* 2 * Copyright (C) 2005 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_STRONG_POINTER_H 18 #define ANDROID_STRONG_POINTER_H 19 20 #include <cutils/atomic.h> 21 22 #include <stdint.h> 23 #include <sys/types.h> 24 #include <stdlib.h> 25 26 // --------------------------------------------------------------------------- 27 namespace android { 28 29 class TextOutput; 30 TextOutput& printStrongPointer(TextOutput& to, const void* val); 31 32 template<typename T> class wp; 33 34 // --------------------------------------------------------------------------- 35 36 #define COMPARE(_op_) \ 37 inline bool operator _op_ (const sp<T>& o) const { \ 38 return m_ptr _op_ o.m_ptr; \ 39 } \ 40 inline bool operator _op_ (const T* o) const { \ 41 return m_ptr _op_ o; \ 42 } \ 43 template<typename U> \ 44 inline bool operator _op_ (const sp<U>& o) const { \ 45 return m_ptr _op_ o.m_ptr; \ 46 } \ 47 template<typename U> \ 48 inline bool operator _op_ (const U* o) const { \ 49 return m_ptr _op_ o; \ 50 } \ 51 inline bool operator _op_ (const wp<T>& o) const { \ 52 return m_ptr _op_ o.m_ptr; \ 53 } \ 54 template<typename U> \ 55 inline bool operator _op_ (const wp<U>& o) const { \ 56 return m_ptr _op_ o.m_ptr; \ 57 } 58 59 // --------------------------------------------------------------------------- 60 61 template <typename T> 62 class sp 63 { 64 public: 65 inline sp() : m_ptr(0) { } 66 67 sp(T* other); 68 sp(const sp<T>& other); 69 template<typename U> sp(U* other); 70 template<typename U> sp(const sp<U>& other); 71 72 ~sp(); 73 74 // Assignment 75 76 sp& operator = (T* other); 77 sp& operator = (const sp<T>& other); 78 79 template<typename U> sp& operator = (const sp<U>& other); 80 template<typename U> sp& operator = (U* other); 81 82 //! Special optimization for use by ProcessState (and nobody else). 83 void force_set(T* other); 84 85 // Reset 86 87 void clear(); 88 89 // Accessors 90 91 inline T& operator* () const { return *m_ptr; } 92 inline T* operator-> () const { return m_ptr; } 93 inline T* get() const { return m_ptr; } 94 95 // Operators 96 97 COMPARE(==) 98 COMPARE(!=) 99 COMPARE(>) 100 COMPARE(<) 101 COMPARE(<=) 102 COMPARE(>=) 103 104 private: 105 template<typename Y> friend class sp; 106 template<typename Y> friend class wp; 107 void set_pointer(T* ptr); 108 T* m_ptr; 109 }; 110 111 #undef COMPARE 112 113 template <typename T> 114 TextOutput& operator<<(TextOutput& to, const sp<T>& val); 115 116 // --------------------------------------------------------------------------- 117 // No user serviceable parts below here. 118 119 template<typename T> 120 sp<T>::sp(T* other) 121 : m_ptr(other) 122 { 123 if (other) other->incStrong(this); 124 } 125 126 template<typename T> 127 sp<T>::sp(const sp<T>& other) 128 : m_ptr(other.m_ptr) 129 { 130 if (m_ptr) m_ptr->incStrong(this); 131 } 132 133 template<typename T> template<typename U> 134 sp<T>::sp(U* other) : m_ptr(other) 135 { 136 if (other) ((T*)other)->incStrong(this); 137 } 138 139 template<typename T> template<typename U> 140 sp<T>::sp(const sp<U>& other) 141 : m_ptr(other.m_ptr) 142 { 143 if (m_ptr) m_ptr->incStrong(this); 144 } 145 146 template<typename T> 147 sp<T>::~sp() 148 { 149 if (m_ptr) m_ptr->decStrong(this); 150 } 151 152 template<typename T> 153 sp<T>& sp<T>::operator = (const sp<T>& other) { 154 T* otherPtr(other.m_ptr); 155 if (otherPtr) otherPtr->incStrong(this); 156 if (m_ptr) m_ptr->decStrong(this); 157 m_ptr = otherPtr; 158 return *this; 159 } 160 161 template<typename T> 162 sp<T>& sp<T>::operator = (T* other) 163 { 164 if (other) other->incStrong(this); 165 if (m_ptr) m_ptr->decStrong(this); 166 m_ptr = other; 167 return *this; 168 } 169 170 template<typename T> template<typename U> 171 sp<T>& sp<T>::operator = (const sp<U>& other) 172 { 173 T* otherPtr(other.m_ptr); 174 if (otherPtr) otherPtr->incStrong(this); 175 if (m_ptr) m_ptr->decStrong(this); 176 m_ptr = otherPtr; 177 return *this; 178 } 179 180 template<typename T> template<typename U> 181 sp<T>& sp<T>::operator = (U* other) 182 { 183 if (other) ((T*)other)->incStrong(this); 184 if (m_ptr) m_ptr->decStrong(this); 185 m_ptr = other; 186 return *this; 187 } 188 189 template<typename T> 190 void sp<T>::force_set(T* other) 191 { 192 other->forceIncStrong(this); 193 m_ptr = other; 194 } 195 196 template<typename T> 197 void sp<T>::clear() 198 { 199 if (m_ptr) { 200 m_ptr->decStrong(this); 201 m_ptr = 0; 202 } 203 } 204 205 template<typename T> 206 void sp<T>::set_pointer(T* ptr) { 207 m_ptr = ptr; 208 } 209 210 template <typename T> 211 inline TextOutput& operator<<(TextOutput& to, const sp<T>& val) 212 { 213 return printStrongPointer(to, val.get()); 214 } 215 216 }; // namespace android 217 218 // --------------------------------------------------------------------------- 219 220 #endif // ANDROID_STRONG_POINTER_H 221
