Вопросы по C++ (6 стр)

#ifndef LIB_M_CTIMER_M_H_
#define LIB_M_CTIMER_M_H_

#include <windows.h>

class CTimer_m {
private:
    DWORD   thID;

    int     period; // 1000 = 1 sec
    bool    timer_on;

    static DWORD WINAPI threadTimerGo(LPVOID IpParam);

    int timerTick();
    void (*procTimer)();
public:
    CTimer_m(int per);
    ~CTimer_m();

    void timerOn();
    void timerOff();

    bool setProcTimer(void (*proc)());
};

#endif /* LIB_M_CTIMER_M_H_ */

#include "CTimer_m.h"
#include <iostream>

//========================================================================
//========================================================================
CTimer_m::CTimer_m(int per) {
    procTimer   = NULL;
    timer_on    = false;
    period      = per;

    CreateThread(NULL, 0, threadTimerGo, this, 0, &thID);
    std::cout << "=== Start Thread Timer" << std::endl;
}

//========================================================================
//========================================================================
CTimer_m::~CTimer_m() {
    // TODO Auto-generated destructor stub
}

//========================================================================
//========================================================================
DWORD WINAPI CTimer_m::threadTimerGo(LPVOID IpParam) {
    CTimer_m *pThis = reinterpret_cast<CTimer_m*>(IpParam);
    return pThis->timerTick();
}

//========================================================================
//========================================================================
int CTimer_m::timerTick() {
    LARGE_INTEGER   time_s;
    LARGE_INTEGER   freq;
    int             time_1;
    int             time_2;

    QueryPerformanceFrequency(&freq);
    QueryPerformanceCounter(&time_s);
    time_1 = time_s.QuadPart / (freq.QuadPart/1000);

    while (1) {
        QueryPerformanceCounter(&time_s);
        time_2 = time_s.QuadPart / (freq.QuadPart/1000);
        if (time_2 > time_1 && timer_on) {
            time_1 += period;
            if (time_2 > time_1) {
                time_1 = time_2 + period;
            }
            if (procTimer != NULL) {
                procTimer();
            }
        }
        Sleep(1);
    }

    return 0;
}

//========================================================================
//========================================================================
void CTimer_m::timerOn() {
    timer_on = true;
}

//========================================================================
//========================================================================
void CTimer_m::timerOff() {
    timer_on = false;
}

//========================================================================
//========================================================================
bool CTimer_m::setProcTimer(void (*proc)()) {
    if (proc == NULL)
        return false;

    procTimer = proc;
    return true;
}