Function check_task_monitoring

tests/BS_thread_pool_test.cpp:2049–2085

* @brief Check that task monitoring works. */

 * @brief Check that task monitoring works.
 */
void check_task_monitoring()
{
    constexpr std::chrono::milliseconds sleep_time(300);
    const std::size_t num_threads = std::min<std::size_t>(std::thread::hardware_concurrency(), 4);
    logln("Creating pool with ", num_threads, " threads.");
    BS::thread_pool pool(num_threads);
    logln("Submitting ", num_threads * 3, " tasks.");
    counting_semaphore sem(0);
    for (std::size_t i = 0; i < num_threads * 3; ++i)
    {
        pool.detach_task(
            [i, &sem]
            {
                sem.acquire();
                logln("Task ", i, " released.");
            });
    }
    std::this_thread::sleep_for(sleep_time);
    logln("After submission, should have: ", num_threads * 3, " tasks total, ", num_threads, " tasks running, ", num_threads * 2, " tasks queued...");
    log("Result: ", pool.get_tasks_total(), " tasks total, ", pool.get_tasks_running(), " tasks running, ", pool.get_tasks_queued(), " tasks queued ");
    check(pool.get_tasks_total() == num_threads * 3 && pool.get_tasks_running() == num_threads && pool.get_tasks_queued() == num_threads * 2);
    sem.release(static_cast<std::ptrdiff_t>(num_threads));
    std::this_thread::sleep_for(sleep_time);
    logln("After releasing ", num_threads, " tasks, should have: ", num_threads * 2, " tasks total, ", num_threads, " tasks running, ", num_threads, " tasks queued...");
    log("Result: ", pool.get_tasks_total(), " tasks total, ", pool.get_tasks_running(), " tasks running, ", pool.get_tasks_queued(), " tasks queued ");
    check(pool.get_tasks_total() == num_threads * 2 && pool.get_tasks_running() == num_threads && pool.get_tasks_queued() == num_threads);
    sem.release(static_cast<std::ptrdiff_t>(num_threads));
    std::this_thread::sleep_for(sleep_time);
    logln("After releasing ", num_threads, " more tasks, should have: ", num_threads, " tasks total, ", num_threads, " tasks running, ", 0, " tasks queued...");
    log("Result: ", pool.get_tasks_total(), " tasks total, ", pool.get_tasks_running(), " tasks running, ", pool.get_tasks_queued(), " tasks queued ");
    check(pool.get_tasks_total() == num_threads && pool.get_tasks_running() == num_threads && pool.get_tasks_queued() == 0);
    sem.release(static_cast<std::ptrdiff_t>(num_threads));
    std::this_thread::sleep_for(sleep_time);
    logln("After releasing the final ", num_threads, " tasks, should have: ", 0, " tasks total, ", 0, " tasks running, ", 0, " tasks queued...");
    log("Result: ", pool.get_tasks_total(), " tasks total, ", pool.get_tasks_running(), " tasks running, ", pool.get_tasks_queued(), " tasks queued ");
    check(pool.get_tasks_total() == 0 && pool.get_tasks_running() == 0 && pool.get_tasks_queued() == 0);
}

/**
 * @brief Check that pausing works.