/* geiger.c */

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <time.h>

int main(int argc, char *argv[])
{
    int fd, flags, prevcts, count, events;

    if ((fd = open("/dev/cua0", O_RDONLY)) < 0) return 1;
    prevcts = -1;
    count = events = 0;
    while (ioctl(fd, TIOCMGET, &flags) == 0) {
        int cts = (flags & TIOCM_CTS);
        time_t t = time(0);
        struct tm *lt = localtime(&t);
        if (prevcts == -1) {
            prevcts = cts;
        } else if (cts != prevcts) {
            events++;
            prevcts = cts;
        }
        if (++count > 3000 && lt->tm_sec == 0 && lt->tm_min % 10 == 0) {
            FILE *f = fopen("/usr/local/apache/htdocs/geiger.dat", "a");
            if (f != NULL) {
                fprintf(f, "%04d-%02d-%02d %02d:%02d %d\n",
                        lt->tm_year + 1900, lt->tm_mon + 1, lt->tm_mday,
                        lt->tm_hour, lt->tm_min, events);
                fclose(f);
            }
            count = events = 0;
        }
        usleep(100000);
    }
    close(fd);
    return 0;
}