C++手写阻塞队列（纯C++11）

这个图可以解释阻塞队列要做什么，阻塞队列主要用于线程和线程之间的通信。当队列为空时，从队列中获取元素的线程将会被挂起；当队列是满时，往队列里添加元素的线程将会挂起。

#pragma once #include <condition_variable> #include <mutex> #include <deque> template<class T> class BlockQueue { public: typedef std::unique_lock<std::mutex> TLock; //maxCapacity为-1，代表队列无最大限制 explicit BlockQueue(const int maxCapacity = -1):m_maxCapacity(maxCapacity) { } size_t size() { TLock lock(m_mutex); return m_list.size(); } void push_back(const T &item) { TLock lock(m_mutex); if (true == hasCapacity()) { while (m_list.size() >= m_maxCapacity) { m_notFull.wait(lock); } } m_list.push_back(item); m_notEmpty.notify_all(); } T pop() { TLock lock(m_mutex); while (m_list.empty()) { m_notEmpty.wait(lock); } T temp = *m_list.begin(); m_list.pop_front(); m_notFull.notify_all(); lock.unlock(); return temp; } bool empty() { TLock lock(m_mutex); return m_list.empty(); } bool full() { if (false == hasCapacity) { return false; } TLock lock(m_mutex); return m_list.size() >= m_maxCapacity; } private: bool hasCapacity() const { return m_maxCapacity > 0; } typedef std::deque<T> TList; TList m_list; const int m_maxCapacity; std::mutex m_mutex; std::condition_variable m_notEmpty; std::condition_variable m_notFull; };

测试部分

#include <iostream> #include <thread> #include <stdio.h> using namespace std; typedef BlockQueue<int> TQueue; void produce(TQueue &queue) { const int num = 9; for (int i = 0; i < num; ++i) { queue.push_back(i); } } void consume(TQueue &queue) { while (false==queue.empty()) { int tmp = queue.pop(); printf("%d\n", tmp); std::this_thread::sleep_for(chrono::seconds(1)); } } int main() { TQueue queue(2); std::thread t1(produce, std::ref(queue)); std::thread t2(consume, std::ref(queue)); std::thread t3(consume, std::ref(queue)); t3.join(); t2.join(); t1.join(); return 0; }