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- 新增现代 C++ 教程的 Preface 章节，包括英文和中文版本 - 添加 C++ Primer 练习代码 - 新增 Learn C++ 教程的 C++ 开发简介章节 - 添加头文件解析文档 - 更新 mkdocs.yml，包含新教程的目录结构 - 修改项目设置，使用 Python 3.10环境
65 lines
1.7 KiB
C++
65 lines
1.7 KiB
C++
//
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// 7.5.producer.consumer.cpp
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// chapter 7 parallelism and concurrency
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// modern c++ tutorial
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//
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// created by changkun at changkun.de
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// https://github.com/changkun/modern-cpp-tutorial
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//
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#include <queue>
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#include <chrono>
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#include <mutex>
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#include <thread>
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#include <iostream>
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#include <condition_variable>
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int main() {
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std::queue<int> produced_nums;
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std::mutex mtx;
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std::condition_variable cv;
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bool notified = false; // notification sign
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auto producer = [&]() {
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for (int i = 0; ; i++) {
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std::this_thread::sleep_for(std::chrono::milliseconds(500));
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std::unique_lock<std::mutex> lock(mtx);
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std::cout << "producing " << i << std::endl;
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produced_nums.push(i);
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notified = true;
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cv.notify_all();
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}
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};
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auto consumer = [&]() {
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while (true) {
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std::unique_lock<std::mutex> lock(mtx);
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while (!notified) { // avoid spurious wakeup
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cv.wait(lock);
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}
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// temporal unlock to allow producer produces more rather than
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// let consumer hold the lock until its consumed.
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lock.unlock();
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std::this_thread::sleep_for(std::chrono::milliseconds(1000)); // consumer is slower
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lock.lock();
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if (!produced_nums.empty()) {
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std::cout << "consuming " << produced_nums.front() << std::endl;
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produced_nums.pop();
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}
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notified = false;
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}
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};
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std::thread p(producer);
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std::thread cs[2];
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for (int i = 0; i < 2; ++i) {
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cs[i] = std::thread(consumer);
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}
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p.join();
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for (int i = 0; i < 2; ++i) {
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cs[i].join();
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}
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return 0;
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}
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