threading.cpp

#include <iostream>
#include <mutex>
#include <thread>
#include <chrono>
#include <unistd.h>

std::mutex mx;

//----------------------------------------------------------------------

struct shMemory
{

    int shearedTimer;

} shm;

//----------------------------------------------------------------------

auto get_time()
{

    return std::chrono::high_resolution_clock::now();
}

//----------------------------------------------------------------------

void resetTime(int t, bool resetTime)
{

    if (!resetTime)
    {
        std::cout << "no reset in " << __FUNCTION__ << std::endl;
        shm.shearedTimer++;
    }
    if (resetTime)
    {
        std::cout << " ### RESET ###" << __FUNCTION__ << std::endl;
        shm.shearedTimer = 0;
    }
}
//----------------------------------------------------------------------

void watchDog()
{

    while (true)
    {

        std::this_thread::sleep_for(std::chrono::milliseconds(200));
        std::cout << " ======> " << __FUNCTION__ << " barking " << shm.shearedTimer << " sek" << std::endl;
        mx.lock();
        resetTime(shm.shearedTimer, false);
        mx.unlock();
        if (shm.shearedTimer % 10 == 0)
        {

            std::cout << " Sending Alert..." << std::endl;
        }
    }
}
//----------------------------------------------------------------------

void threadOneWorker(int sleep)
{

    auto start = get_time();

    for (int i = 0; i < 10000; i++)
    {

        std::cout << __FUNCTION__ << std::endl;
        std::this_thread::sleep_for(std::chrono::milliseconds(sleep));
        mx.lock();
        resetTime(0, true);
        mx.unlock();
    }

    auto stop = get_time();
    auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(stop - start);

    std::cout << "total exeqution time of " << __FUNCTION__ << " : " << duration.count() << std::endl;
}
//----------------------------------------------------------------------

void threadTwoWorker(int sleep)
{

    auto start = get_time();

    for (int i = 0; i < 10000; i++)
    {

        std::cout << __FUNCTION__ << std::endl;
        std::this_thread::sleep_for(std::chrono::milliseconds(sleep));
        mx.lock();
        resetTime(0, true);
        mx.unlock();
    }

    auto stop = get_time();
    auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(stop - start);

    std::cout << "total exeqution time of " << __FUNCTION__ << " : " << duration.count() << std::endl;
}
//----------------------------------------------------------------------

int main()
{
    pid_t pid;

    std::cout << "PID : " << getpid() << std::endl;

    std::thread threadOne(threadOneWorker, 1900); // spawn new thread that calls threadOneWorker()
    std::thread threadTwo(threadTwoWorker, 750);  // spawn new thread that calls threadTwoWorker()
    std::thread threadThree(watchDog);            // spawn new thread that calls watchDog()
    threadOne.join();
    threadTwo.join();
    threadThree.join();
}