Linked List Based SPSC Blocking Queue

In this exercise, you'll implement a thread-safe queue using:

• A singly-linked list as the underlying container
• std::mutex and std::condition_variable for synchronization
• Blocking pop() behavior if the queue is empty

This is a basic example of a blocking queue used in multithreaded producer-consumer pipelines. While flexible, the use of dynamic memory makes it less predictable for latency-sensitive workloads.

> 💡 In real systems like logging or event pipelines, such queues help offload work from the main thread without busy waiting.

Requirements

• push(const T&) should add to the back.
• pop() should block if the queue is empty until a new element arrives.
• The queue should allow exactly one producer and one consumer thread.

Bonus: Implement an optional try_pop() and shutdown() method if you're feeling adventurous.

Implement a blocking queue using a linked list with one producer and one consumer.

#include <mutex>
#include <condition_variable>

template <typename T>
class BlockingQueue {
private:
    struct Node;
    // Data members here
public:
    BlockingQueue() {
        // TODO: Initialize data structures
    }

    ~BlockingQueue() {
        // TODO: Cleanup
    }

    void push(const T& val) {
        // TODO: Push to queue
    }

    T pop() {
        // TODO: Pop from queue
    }
};