1// Copyright (C) 2013 The Libphonenumber Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#ifndef I18N_PHONENUMBERS_BASE_MEMORY_SINGLETON_POSIX_H_
16#define I18N_PHONENUMBERS_BASE_MEMORY_SINGLETON_POSIX_H_
17
18#include <pthread.h>
19
20#include "phonenumbers/base/logging.h"
21
22namespace i18n {
23namespace phonenumbers {
24
25template <class T>
26class Singleton {
27 public:
28  virtual ~Singleton() {}
29
30  static T* GetInstance() {
31    const int ret = pthread_once(&once_control_, &Init);
32    (void) ret;
33    DCHECK_EQ(0, ret);
34    return instance_;
35  }
36
37 private:
38  static void Init() {
39    instance_ = new T();
40  }
41
42  static T* instance_;  // Leaky singleton.
43  static pthread_once_t once_control_;
44};
45
46template <class T> T* Singleton<T>::instance_;
47template <class T> pthread_once_t Singleton<T>::once_control_ =
48    PTHREAD_ONCE_INIT;
49
50}  // namespace phonenumbers
51}  // namespace i18n
52
53#endif  // I18N_PHONENUMBERS_BASE_MEMORY_SINGLETON_POSIX_H_
54