#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/time.h>
#include <string.h>
#include "lceb.h"

int sigint_received=0;
int displaytimer=0;
static  struct timespec start;

static void stopall(signum)
    int signum;
{
    printf("SIGNAL %d RECEIVED: aborting eval\n", signum);
    sigint_received=1;
}

int stopped()
{
    return sigint_received;
}

void set_intr()
{
    struct sigaction sig;

    sig.sa_handler = stopall;
    sigemptyset(&sig.sa_mask);
    sig.sa_flags = 0;
    sigaction(SIGINT, &sig, NULL);
    //sigaction(SIGUSR1, &sig, NULL);
#   ifdef DEBUG
    printf("SIGINT armed.\n");
#   endif
}

void set_alarm(ms)
    int ms;
{
    struct sigaction sig;
    struct itimerval timer;

    /* Install timer_handler as the signal handler for SIGVTALRM. */
    //memset (&sa, 0, sizeof (sa));
    sig.sa_handler = stopall;
    sigemptyset(&sig.sa_mask);
    sig.sa_flags = 0;
    sigaction (SIGALRM, &sig, NULL);

    timer.it_value.tv_sec = ms/1000;
    timer.it_value.tv_usec = (ms%1000)*1000;
#   ifdef DEBUG
    printf("alarm clock set to %.2f secs.\n",
           timer.it_value.tv_sec + timer.it_value.tv_usec / 1000000.);
#   endif
    /* ... and every 250 msec after that. */
    timer.it_interval.tv_sec = 0;
    timer.it_interval.tv_usec = 0;
    /* Start a virtual timer. It counts down whenever this process is executing. */
    setitimer (ITIMER_REAL, &timer, NULL);

}

void start_timer()
{
    printf("timer started...\n");
    clock_gettime(CLOCK_MONOTONIC, &start);
#   ifdef DEBUG_TIMER
    printf("sec=%d nsec=%d\n", start.tv_sec, start.tv_nsec);
#   endif
}

void set_timer(timer)
    struct timespec *timer;
{
    clock_gettime(CLOCK_MONOTONIC, timer);
#   ifdef DEBUG_TIMER
    printf("timer: sec=%d nsec=%d orig: sec=%ld nsec=%ld\n",
           timer->tv_sec, timer->tv_nsec, start.tv_sec, start.tv_nsec);
#   endif
}

double get_timer(timer)
    struct timespec timer;
{
    double diff;
    diff=(timer.tv_sec - start.tv_sec) + (timer.tv_nsec - start.tv_nsec) / NANOSEC;
#   ifdef DEBUG_TIMER
    printf("timer sec: %.5f\n", diff);
#   endif
    return diff;
}

#ifdef STANDALONE
int main(ac, av)
    int ac;
    char **av;
{
    int delay;
    struct timespec end;

    if (ac != 2) {
        fprintf(stderr, "usage: %s msecs\n", *av);
        exit (1);
    }
    delay=atoi(*(av+1))*10;
    start_timer();
    set_intr();
    set_alarm(delay);
    //tsdelay.tv_sec=delay/MILLISEC;
    //tsdelay.tv_nsec=delay%MILLISEC;
    //printf("delay %d=%ld:%ld\n", delay, tsdelay.tv_sec, tsdelay.tv_nsec);
    sleep(5);
    set_timer(&end);
    printf("Time elapsed: %.5f seconds\n", get_timer(end));

    return 0;
}
#endif