C++線程安全隊列

C++線程安全隊列

#ifndef COMMON_SOURCE_CPP_THREADSAFE_QUEUE_H_
#define COMMON_SOURCE_CPP_THREADSAFE_QUEUE_H_
#include <queue>
#include <mutex>
#include <condition_variable>
#include <initializer_list>
namespace queueSpace {
        /*
        * 線程安全隊列
        * T為隊列元素類型
        * 因為有std::mutex和std::condition_variable類成員,所以此類不支持復制構造函數也不支持賦值操作符(=)
        * */
        template<typename T>
        class threadsafe_queue{
        private:
            //data_queue訪問信號量
            mutable std::mutex mut;
            mutable std::condition_variable data_cond;
            using queue_type = std::queue<T>;
            queue_type data_queue;
        public:
            using value_type = typename queue_type::value_type;
            using container_type = typename queue_type::container_type;
            threadsafe_queue() = default;
            threadsafe_queue(const threadsafe_queue&) = delete;
            threadsafe_queue& operator=(const threadsafe_queue&) = delete;
            /*
            * 使用迭代器為參數的構造函數,適用所有容器對象
            * */
            template<typename _InputIterator>
            threadsafe_queue(_InputIterator first, _InputIterator last){
                for (auto itor = first; itor != last; ++itor){
                    data_queue.push(*itor);
                }
            }
            explicit threadsafe_queue(const container_type &c) :data_queue(c){}
            /*
            * 使用初始化列表為參數的構造函數
            * */
            threadsafe_queue(std::initializer_list<value_type> list) :threadsafe_queue(list.begin(), list.end()){
            }
            /*
            * 將元素加入隊列
            * */
            void push(const value_type &new_value){
                std::lock_guard<std::mutex>lk(mut);
                    data_queue.push(std::move(new_value));
                    data_cond.notify_one();
            }

            /*
            * 從隊列中彈出一個元素,如果隊列為空就阻塞
            * */
            value_type wait_and_pop(){
                std::unique_lock<std::mutex>lk(mut);
                data_cond.wait(lk, [this]{return !this->data_queue.empty(); });
                auto value = std::move(data_queue.front());
                data_queue.pop();
                return value;
            }
            /*
            * 從隊列中彈出一個元素,如果隊列為空返回false
            * */
            bool try_pop(value_type& value){
                std::lock_guard<std::mutex>lk(mut);
                if (data_queue.empty())
                    return false;
                value = std::move(data_queue.front());
                data_queue.pop();
                return true;
            }
            /*
            * 返回隊列是否為空
            * */
            auto empty() const->decltype(data_queue.empty()) {
                std::lock_guard<std::mutex>lk(mut);
                return data_queue.empty();
            }
            /*
            * 返回隊列中元素數個
            * */
            auto size() const->decltype(data_queue.size()){
                std::lock_guard<std::mutex>lk(mut);
                return data_queue.size();
            }
        }; /* threadsafe_queue */
}/* namespace queueSpace */
#endif /* COMMON_SOURCE_CPP_THREADSAFE_QUEUE_H_ */