Function check_shared_ptr

tests/BS_thread_pool_test.cpp:2643–2682

* @brief Check, for a specific member function which parallelizes loops or sequences of tasks, that if a task that captures a shared pointer is submitted, the pointer is correctly shared between all the iterations of the task. * * @param which_func A string naming the function to check. */

 * @param which_func A string naming the function to check.
 */
void check_shared_ptr(const std::string_view which_func)
{
    BS::thread_pool pool;
    constexpr std::chrono::milliseconds sleep_time(10);
    const std::size_t num_tasks = pool.get_thread_count() * 10;
    std::atomic<bool> object_exists = false;
    std::atomic<std::size_t> uses_before_destruct = 0;
    std::atomic<std::size_t> uses_after_destruct = 0;
    logln("Checking ", which_func, "...");
    {
        std::shared_ptr<detect_destruct> ptr = std::make_shared<detect_destruct>(&object_exists);
        auto task = [ptr, &object_exists, &uses_before_destruct, &uses_after_destruct, &sleep_time](auto&&...)
        {
            std::this_thread::sleep_for(sleep_time);
            if (object_exists)
                ++uses_before_destruct;
            else
                ++uses_after_destruct;
        };
        if (which_func == "detach_blocks()")
            pool.detach_blocks(0, num_tasks, std::move(task), num_tasks);
        else if (which_func == "detach_loop()")
            pool.detach_loop(0, num_tasks, std::move(task));
        else if (which_func == "detach_sequence()")
            pool.detach_sequence(0, num_tasks, std::move(task));
        else if (which_func == "submit_blocks()")
            std::ignore = pool.submit_blocks(0, num_tasks, std::move(task), num_tasks);
        else if (which_func == "submit_loop()")
            std::ignore = pool.submit_loop(0, num_tasks, std::move(task));
        else if (which_func == "submit_sequence()")
            std::ignore = pool.submit_sequence(0, num_tasks, std::move(task));
        ptr.reset();
    }
    pool.wait();
    std::this_thread::sleep_for(sleep_time);
    logln("Uses before destruct:");
    check(num_tasks, uses_before_destruct.load());
    logln("Uses after destruct:");
    check(0, uses_after_destruct.load());
}

/**
 * @brief Check, for all member functions which parallelize loops or sequences of tasks, that if a task that captures a shared pointer is submitted, the pointer is correctly shared between all the iterations of the task.