1// Copyright (C) 2011 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// Author: Philippe Liard 16 17#ifndef I18N_PHONENUMBERS_BASE_MEMORY_SINGLETON_H_ 18#define I18N_PHONENUMBERS_BASE_MEMORY_SINGLETON_H_ 19 20#if defined(I18N_PHONENUMBERS_USE_BOOST) 21 22#include <boost/scoped_ptr.hpp> 23#include <boost/thread/once.hpp> 24#include <boost/utility.hpp> 25 26namespace i18n { 27namespace phonenumbers { 28 29template <class T> 30class Singleton : private boost::noncopyable { 31 public: 32 virtual ~Singleton() {} 33 34 static T* GetInstance() { 35 boost::call_once(Init, flag); 36 return instance.get(); 37 } 38 39 private: 40 static void Init() { 41 instance.reset(new T()); 42 } 43 44 static boost::scoped_ptr<T> instance; 45 static boost::once_flag flag; 46}; 47 48template <class T> boost::scoped_ptr<T> Singleton<T>::instance; 49template <class T> boost::once_flag Singleton<T>::flag = BOOST_ONCE_INIT; 50 51} // namespace phonenumbers 52} // namespace i18n 53 54#else // !I18N_PHONENUMBERS_USE_BOOST 55 56#include "phonenumbers/base/logging.h" 57#include "phonenumbers/base/thread_checker.h" 58 59#if !defined(__linux__) && !defined(__APPLE__) 60 61namespace i18n { 62namespace phonenumbers { 63 64// Note that this implementation is not thread-safe. For a thread-safe 65// implementation on non-POSIX platforms, please compile with 66// -DI18N_PHONENUMBERS_USE_BOOST. 67template <class T> 68class Singleton { 69 public: 70 Singleton() : thread_checker_() {} 71 72 virtual ~Singleton() {} 73 74 static T* GetInstance() { 75 static T* instance = NULL; 76 if (!instance) { 77 instance = new T(); 78 } 79 DCHECK(instance->thread_checker_.CalledOnValidThread()); 80 return instance; 81 } 82 83 private: 84 const ThreadChecker thread_checker_; 85}; 86 87} // namespace phonenumbers 88} // namespace i18n 89 90#else 91#include "phonenumbers/base/memory/singleton_posix.h" 92#endif // !defined(__linux__) && !defined(__APPLE__) 93 94#endif // !I18N_PHONENUMBERS_USE_BOOST 95#endif // I18N_PHONENUMBERS_BASE_MEMORY_SINGLETON_H_ 96