1// Protocol Buffers - Google's data interchange format
2// Copyright 2014 Google Inc.  All rights reserved.
3// https://developers.google.com/protocol-buffers/
4//
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8//
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10// notice, this list of conditions and the following disclaimer.
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13// in the documentation and/or other materials provided with the
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18//
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20// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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30#ifndef GOOGLE_PROTOBUF_STUBS_SINGLETON_H__
31#define GOOGLE_PROTOBUF_STUBS_SINGLETON_H__
32
33#include <google/protobuf/stubs/atomicops.h>
34#include <google/protobuf/stubs/common.h>
35#include <google/protobuf/stubs/once.h>
36
37namespace google {
38namespace protobuf {
39namespace internal {
40template<typename T>
41class Singleton {
42 public:
43  static T* get() {
44    GoogleOnceInit(&once_, &Singleton<T>::Init);
45    return instance_;
46  }
47  static void ShutDown() {
48    delete instance_;
49    instance_ = NULL;
50  }
51 private:
52  static void Init() {
53    instance_ = new T();
54  }
55  static ProtobufOnceType once_;
56  static T* instance_;
57};
58
59template<typename T>
60ProtobufOnceType Singleton<T>::once_;
61
62template<typename T>
63T* Singleton<T>::instance_ = NULL;
64}  // namespace internal
65}  // namespace protobuf
66}  // namespace google
67
68#endif  // GOOGLE_PROTOBUF_STUBS_SINGLETON_H__
69