1/*
2 * Copyright (C) 2016 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 CHRE_UTIL_SINGLETON_IMPL_H_
18#define CHRE_UTIL_SINGLETON_IMPL_H_
19
20#include <new>
21#include <utility>
22
23#include "chre/util/singleton.h"
24
25namespace chre {
26
27template<typename ObjectType>
28typename std::aligned_storage<sizeof(ObjectType), alignof(ObjectType)>::type
29    Singleton<ObjectType>::sObject;
30
31template<typename ObjectType>
32bool Singleton<ObjectType>::sIsInitialized = false;
33
34template<typename ObjectType>
35template<typename... Args>
36void Singleton<ObjectType>::init(Args&&... args) {
37  if (!sIsInitialized) {
38    sIsInitialized = true;
39    new (get()) ObjectType(std::forward<Args>(args)...);
40  }
41}
42
43template<typename ObjectType>
44void Singleton<ObjectType>::deinit() {
45  if (sIsInitialized) {
46    get()->~ObjectType();
47    sIsInitialized = false;
48  }
49}
50
51template<typename ObjectType>
52bool Singleton<ObjectType>::isInitialized() {
53  return sIsInitialized;
54}
55
56template<typename ObjectType>
57ObjectType *Singleton<ObjectType>::get() {
58  return reinterpret_cast<ObjectType *>(&sObject);
59}
60
61template<typename ObjectType>
62ObjectType *Singleton<ObjectType>::safeGet() {
63  if (sIsInitialized) {
64    return reinterpret_cast<ObjectType *>(&sObject);
65  } else {
66    return nullptr;
67  }
68}
69
70}  // namespace chre
71
72#endif  // CHRE_UTIL_SINGLETON_IMPL_H_
73