| // Copyright 2010-2014, Google Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #ifndef MOZC_BASE_SINGLETON_H_ |
| #define MOZC_BASE_SINGLETON_H_ |
| |
| #include "base/mutex.h" |
| |
| namespace mozc { |
| |
| class SingletonFinalizer { |
| public: |
| typedef void (*FinalizerFunc)(); |
| |
| // Do not call this method directly. |
| // use Singleton<Typename> instead. |
| static void AddFinalizer(FinalizerFunc func); |
| |
| // Call Finalize() if you want to finalize |
| // all instances created by Sigleton. |
| // |
| // Mozc UI for Windows (DLL) can call |
| // SigletonFinalizer::Finalize() |
| // at an appropriate timing. |
| static void Finalize(); |
| }; |
| |
| // Thread-safe Singleton class. |
| // Usage: |
| // |
| // class Foo {} |
| // |
| // Foo *instance = mozc::Singleton<Foo>::get(); |
| template <typename T> |
| class Singleton { |
| public: |
| static T *get() { |
| CallOnce(&once_, &Singleton<T>::Init); |
| return instance_; |
| } |
| |
| private: |
| static void Init() { |
| SingletonFinalizer::AddFinalizer(&Singleton<T>::Delete); |
| instance_ = new T; |
| } |
| |
| static void Delete() { |
| delete instance_; |
| instance_ = NULL; |
| ResetOnce(&once_); |
| } |
| |
| static once_t once_; |
| static T *instance_; |
| }; |
| |
| template <typename T> |
| once_t Singleton<T>::once_ = MOZC_ONCE_INIT; |
| |
| template <typename T> |
| T* Singleton<T>::instance_ = NULL; |
| } // namespace mozc |
| |
| #endif // MOZC_BASE_SINGLETON_H_ |