實現NCThread功能

功能描述：定義一個類，繼承NCThread 類，調用start函數就可以啓動一個線程，線程調用子類的run函數

步驟：

1. 定義父類NCThread，定義一個靜態函數，函數參數爲void*，這裏會傳該類的指針進來
2. 父類NCThread中定義run函數，注意爲virtual，這樣纔可以調到子類的run函數
3. 父類NCThread定義start函數，啓動一個線程，線程函數爲該類中的靜態函數，參數爲this指針
4. 定義子類MyThread，重寫父類的run函數

#include <iostream>
#include <thread>
#include <unistd.h>
#include <atomic>

using namespace std;

std::atomic<int> global_counter (0);
void increase_global (int n) {
    for (int i=0; i<n; ++i)
        cout << ++global_counter << endl;
}

class NCThread {
public:
    static void* pthread_func(void* param) {
        NCThread *m_thread = (NCThread*)param;
        if (m_thread != nullptr) {
            m_thread->run();
        }
    }

    static void thread_func(void* param) {
        NCThread *m_thread = (NCThread*)param;
        m_thread->run();
    }
    virtual void run() {
       cout << "father:run()" << endl;
    }
    void start() {
        cout << "thread start0" << endl;
        thread t2(thread_func, (void*)this);
        t2.detach();
        cout << "thread start1" << endl;
        //pthread_create(&id, NULL, pthread_func, (void *)this);
    }
private:
    pthread_t id;
};


class MyThread : public NCThread {
public:
    void run() {
        while (1) {
            m_i++;
            cout << "time:" << m_i << endl;
            sleep(1);
        }
    }
private:
    int m_i = 0;
};

int main() {
    MyThread myThread;
    myThread.start();
    //std::thread t1(increase_global,1000);
    //t1.join();

    sleep(10);
    return -1;
}