1/* 2 * Copyright (C) 2012 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 ART_RUNTIME_ATOMIC_INTEGER_H_ 18#define ART_RUNTIME_ATOMIC_INTEGER_H_ 19 20#include "cutils/atomic.h" 21#include "cutils/atomic-inline.h" 22 23namespace art { 24 25class AtomicInteger { 26 public: 27 AtomicInteger() : value_(0) { } 28 29 explicit AtomicInteger(int32_t value) : value_(value) { } 30 31 // Unsafe = operator for non atomic operations on the integer. 32 void store(int32_t desired) { 33 value_ = desired; 34 } 35 36 AtomicInteger& operator=(int32_t desired) { 37 store(desired); 38 return *this; 39 } 40 41 int32_t load() const { 42 return value_; 43 } 44 45 operator int32_t() const { 46 return load(); 47 } 48 49 int32_t fetch_add(const int32_t value) { 50 return android_atomic_add(value, &value_); 51 } 52 53 int32_t fetch_sub(const int32_t value) { 54 return android_atomic_add(-value, &value_); 55 } 56 57 int32_t operator++() { 58 return android_atomic_inc(&value_) + 1; 59 } 60 61 int32_t operator++(int32_t) { 62 return android_atomic_inc(&value_); 63 } 64 65 int32_t operator--() { 66 return android_atomic_dec(&value_) - 1; 67 } 68 69 int32_t operator--(int32_t) { 70 return android_atomic_dec(&value_); 71 } 72 73 bool compare_and_swap(int32_t expected_value, int32_t desired_value) { 74 return android_atomic_cas(expected_value, desired_value, &value_) == 0; 75 } 76 77 private: 78 volatile int32_t value_; 79}; 80 81} // namespace art 82 83#endif // ART_RUNTIME_ATOMIC_INTEGER_H_ 84