prepare for c++17

code/7/7.2.cpp

@@ -0,0 +1,61 @@
+//
+// 7.2.cpp
+// c++1x tutorial
+//
+// created by changkun at shiyanlou.com
+//
+// 生产者消费者模型
+
+#include <condition_variable>
+#include <mutex>
+#include <thread>
+#include <iostream>
+#include <queue>
+#include <chrono>
+
+int main()
+{
+    // 生产者数量
+    std::queue<int> produced_nums;
+    // 互斥锁
+    std::mutex m;
+    // 条件变量
+    std::condition_variable cond_var;
+    // 结束标志
+    bool done = false;
+    // 通知标志
+    bool notified = false;
+    
+    // 生产者线程
+    std::thread producer([&]() {
+        for (int i = 0; i < 5; ++i) {
+            std::this_thread::sleep_for(std::chrono::seconds(1));
+            // 创建互斥锁
+            std::unique_lock<std::mutex> lock(m);
+            std::cout << "producing " << i << '\n';
+            produced_nums.push(i);
+            notified = true;
+            // 通知一个线程
+            cond_var.notify_one();
+        }
+        done = true;
+        cond_var.notify_one();
+    });
+    // 消费者线程
+    std::thread consumer([&]() {
+        std::unique_lock<std::mutex> lock(m);
+        while (!done) {
+            while (!notified) {  // 循环避免虚假唤醒
+                cond_var.wait(lock);
+            }
+            while (!produced_nums.empty()) {
+                std::cout << "consuming " << produced_nums.front() << '\n';
+                produced_nums.pop();
+            }
+            notified = false;
+        }
+    });
+    
+    producer.join();
+    consumer.join();
+}