#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <time.h>
#include <string.h>

//#define CLOCKID CLOCK_REALTIME
#define CLOCKID    CLOCK_MONOTONIC

#define SIG SIGRTMIN   //實時訊號，可靠訊號

#define errExit(msg)    do { perror(msg); exit(EXIT_FAILURE); \
        } while (0)



static void
print_siginfo(siginfo_t *si)
{
    timer_t *tidp;
    int or;

    tidp = si->si_value.sival_ptr;

    printf("    sival_ptr = %p; ", si->si_value.sival_ptr);
    printf("    *sival_ptr = 0x%lx\n", (long) *tidp);

    or = timer_getoverrun(*tidp);
    if (or == -1)
        errExit("timer_getoverrun");
    else
        printf("    overrun count = %d\n", or);
}

static void
handler(int sig, siginfo_t *si, void *uc)
{
    /* Note: calling printf() from a signal handler is not
              strictly correct, since printf() is not async-signal-safe;
              see signal(7)
     */

    printf("Caught signal %d\n", sig);
    print_siginfo(si);
    //signal(sig, SIG_IGN);
}



static void
handler2(union sigval v)
{

    timer_t *tidp;
    tidp=v.sival_ptr;
    printf("Caught handler2 0x%lx\n",*(long *)tidp);//列印傳遞的引數


}


typedef  void (*sigHandler)(int , siginfo_t *, void *);
typedef  void (*pthHandler)(union sigval);

//定時器通知方式為訊號的處理方式
int testTimerSign(timer_t *pTimerid, struct itimerspec ts, int sig, sigHandler handler){

    struct sigevent evp;
    struct sigaction sa;
    int ret=0;

    printf("Establishing handler for signal %d\n", SIG);

    sa.sa_flags = SA_SIGINFO;
    sa.sa_sigaction = handler;
    sigemptyset(&sa.sa_mask);

    //安裝訊號處理函式
    if (sigaction(sig, &sa, NULL) == -1)
    {
        perror("testTimerSign:sigaction");
        ret=-1;
    }

    memset(&evp,0,sizeof(evp));
    evp.sigev_notify =SIGEV_SIGNAL;
    evp.sigev_signo = sig;
    evp.sigev_value.sival_ptr = pTimerid; //傳遞的引數,指標型

    ret = timer_create(CLOCKID, &evp, pTimerid);
    if(ret) {
        perror("timer_create");
    }

    printf("timer ID is 0x%lx\n", (long) *pTimerid);

    //  ts.it_value.tv_sec = 1;
    //  ts.it_value.tv_nsec = 10000000;
    //  ts.it_interval.tv_sec = its.it_value.tv_sec;
    //  ts.it_interval.tv_nsec = its.it_value.tv_nsec;
    printf("testTimerSign:start timer\n");
    ret = timer_settime(*pTimerid, 0, &ts, NULL);
    if(ret) {
        perror("timer_settime\n");
    }
    return ret;
}

//定時器通知方式為執行緒方式
int testTimerThread(timer_t *pTimerid,struct itimerspec its,pthHandler handler)
{
    struct sigevent sev;
    int ret=0;

    memset(&sev,0,sizeof(sev));
    sev.sigev_notify = SIGEV_THREAD;
    sev.sigev_notify_function=handler;//處理函式
    sev.sigev_value.sival_ptr = pTimerid;//傳遞給處理函式的引數，指標型
    //sev.sigev_value.sival_int=timerid;
    if (timer_create(CLOCKID, &sev, pTimerid) == -1)
    {
        perror("timer_create\n");
        ret=-1;
    }

    printf("timer ID is 0x%lx\n", (long) *pTimerid);


    //  its.it_value.tv_sec = 1;
    //  its.it_value.tv_nsec = 10000000;
    //  its.it_interval.tv_sec = its.it_value.tv_sec;
    //  its.it_interval.tv_nsec = its.it_value.tv_nsec;

    if (timer_settime(*pTimerid, 0, &its, NULL) == -1)
    {
        perror("timer_settime\n");
        ret=-1;
    }

    return ret;

}

int
main(int argc, char *argv[])
{
    timer_t timerid1,timerid2;
    struct  itimerspec ts1,ts2;

    if (argc != 2) {
        fprintf(stderr, "Usage: %s <sleep-secs>\n",
                argv[0]);
        exit(EXIT_FAILURE);
    }

    ts1.it_value.tv_sec =  1;  //定時器初次觸發時間
    ts1.it_value.tv_nsec = 0;
    ts1.it_interval.tv_sec = ts1.it_value.tv_sec;  //定時器週期性間隔時間
    ts1.it_interval.tv_nsec = ts1.it_value.tv_nsec;

    ts2.it_value.tv_sec =  4;  //定時器初次觸發時間
    ts2.it_value.tv_nsec = 0;
    ts2.it_interval.tv_sec = 2;  //定時器週期性間隔時間
    ts2.it_interval.tv_nsec = 0;

    testTimerSign(&timerid1,ts1,SIG,handler);
    testTimerThread(&timerid2,ts2,handler2);

    /*
     *
     * Sleep for a while; meanwhile, the timer may expire
              multiple times
     */

    printf("Sleeping for %d seconds\n", atoi(argv[1]));
    while(1)
        sleep(atoi(argv[1]));


    exit(EXIT_SUCCESS);
}