/*
 * Copyright (C) 2016 Rockchip Electronics Co., Ltd.
 * Authors:
 *    Zhiqin Wei <wzq@rock-chips.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _LIBS_RGA_SINGLETON_H
#define _LIBS_RGA_SINGLETON_H

#include "RgaMutex.h"

#if defined(__clang__)
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wundefined-var-template"
#endif

template <typename TYPE> class RgaSingleton {
public:
    static TYPE& getInstance()
    {
        RgaMutex::Autolock _l(sLock);
        TYPE *instance = sInstance;
        if (instance == nullptr) {
            instance = new TYPE();
            sInstance = instance;
        }
        return *instance;
    }
    static bool hasInstance()
    {
        RgaMutex::Autolock _l(sLock);
        return sInstance != nullptr;
    }

protected:
    ~RgaSingleton()
    {
    }
    RgaSingleton()
    {
    }

private:
    RgaSingleton(const RgaSingleton &);
    RgaSingleton &operator=(const RgaSingleton &);
    static RgaMutex sLock;
    static TYPE *sInstance;
};

#if defined(__clang__)
#pragma clang diagnostic pop
#endif

#define RGA_SINGLETON_STATIC_INSTANCE(TYPE)                                                                            \
    do {                                                                                                               \
        template <>::RgaMutex(::RgaSingleton<TYPE>::sLock)(::RgaMutex::PRIVATE);                                       \
        template <> TYPE * ::RgaSingleton<TYPE>::sInstance(nullptr); /* NOLINT */                                      \
        template class ::RgaSingleton<TYPE>;                                                                           \
    } while (0)

#endif // _LIBS_RGA_SINGLETON_H