Exemple #1
0
int main(int argc, char *argv[])
{
	unsigned long sleep_time;
	double read_interval;
	
	start_time = time(0);
	memset(&rtiming, 0, sizeof(rtiming));
	rtiming.rt_variance.v_min = FLT_MAX;

	/*
	 * Early initialization before reading config
	 */
	conf_init_pre();
	parse_args_pre(argc, argv);

	/*
	 * Reading the configuration file */
	configfile_read();

	/*
	 * Late initialization after reading config
	 */
	if (parse_args_post(argc, argv))
		return 1;
	conf_init_post();

	module_init();

	read_interval = cfg_read_interval;
	sleep_time = cfg_getint(cfg, "sleep_time");

	if (((double) sleep_time / 1000000.0f) > read_interval)
		sleep_time = (unsigned long) (read_interval * 1000000.0f);

	DBG("Entering mainloop...");

	do {
		/*
		 * E  := Elapsed time
		 * NR := Next Read
		 * LR := Last Read
		 * RI := Read Interval
		 * ST := Sleep Time
		 * C  := Correction
		 */
		timestamp_t e, ri, tmp;
		unsigned long st;

		float_to_timestamp(&ri, read_interval);

		/*
		 * NR := NOW
		 */
		update_timestamp(&rtiming.rt_next_read);
		
		for (;;) {
			output_pre();

			/*
			 * E := NOW
			 */
			update_timestamp(&e);

			/*
			 * IF NR <= E THEN
			 */
			if (timestamp_le(&rtiming.rt_next_read, &e)) {
				timestamp_t c;

				/*
				 * C :=  (NR - E)
				 */
				timestamp_sub(&c, &rtiming.rt_next_read, &e);

				//calc_variance(&c, &ri);

				/*
				 * LR := E
				 */
				copy_timestamp(&rtiming.rt_last_read, &e);

				/*
				 * NR := E + RI + C
				 */
				timestamp_add(&rtiming.rt_next_read, &e, &ri);
				timestamp_add(&rtiming.rt_next_read,
				       &rtiming.rt_next_read, &c);


				reset_update_flags();
				input_read();
				free_unused_elements();
				output_draw();
				output_post();
			}

			if (do_quit)
				exit(0);

			/*
			 * ST := Configured ST
			 */
			st = sleep_time;

			/*
			 * IF (NR - E) < ST THEN
			 */
			timestamp_sub(&tmp, &rtiming.rt_next_read, &e);

			if (tmp.tv_sec < 0)
				continue;

			if (tmp.tv_sec == 0 && tmp.tv_usec < st) {
				if (tmp.tv_usec < 0)
					continue;
				/*
				 * ST := (NR - E)
				 */
				st = tmp.tv_usec;
			}
			
			/*
			 * SLEEP(ST)
			 */
			usleep(st);
		}
	} while (0);

	return 0; /* buddha says i'll never be reached */
}
Exemple #2
0
int main(int argc, char *argv[])
{
	unsigned long sleep_time;
	double read_interval;
	

	start_time = time(0);

	parse_args_pre(argc, argv);
	configfile_read();
	parse_args_post(argc, argv);

	conf_init();
	module_init();

	read_interval = cfg_read_interval;
	sleep_time = cfg_getint(cfg, "sleep_time");

	if (((double) sleep_time / 1000000.0f) > read_interval)
		sleep_time = (unsigned long) (read_interval * 1000000.0f);

	// pipe_start();

	if (cfg_getbool(cfg, "daemon")) {
		init_syslog();
		daemonize();
		write_pidfile();
	}

	drop_privs();

	do {
		/*
		 * E  := Elapsed time
		 * NR := Next Read
		 * LR := Last Read
		 * RI := Read Interval
		 * ST := Sleep Time
		 * C  := Correction
		 */
		timestamp_t e, ri, tmp;
		unsigned long st;

		float_to_timestamp(&ri, read_interval);

		/*
		 * NR := NOW
		 */
		update_timestamp(&rtiming.rt_next_read);
		
		for (;;) {
			output_pre();

			/*
			 * read the chucka chucka pipe
			 */
			// pipe_handle();

			/*
			 * E := NOW
			 */
			update_timestamp(&e);

			/*
			 * IF NR <= E THEN
			 */
			if (timestamp_le(&rtiming.rt_next_read, &e)) {
				timestamp_t c;

				/*
				 * C :=  (NR - E)
				 */
				timestamp_sub(&c, &rtiming.rt_next_read, &e);

				//calc_variance(&c, &ri);

				/*
				 * LR := E
				 */
				copy_timestamp(&rtiming.rt_last_read, &e);

				/*
				 * NR := E + RI + C
				 */
				timestamp_add(&rtiming.rt_next_read, &e, &ri);
				timestamp_add(&rtiming.rt_next_read,
				       &rtiming.rt_next_read, &c);


				reset_update_flags();
				input_read();
				free_unused_elements();
				output_draw();
				output_post();
			}

			if (do_quit)
				exit(0);

			/*
			 * ST := Configured ST
			 */
			st = sleep_time;

			/*
			 * IF (NR - E) < ST THEN
			 */
			timestamp_sub(&tmp, &rtiming.rt_next_read, &e);

			if (tmp.tv_sec < 0)
				continue;

			if (tmp.tv_sec == 0 && tmp.tv_usec < st) {
				if (tmp.tv_usec < 0)
					continue;
				/*
				 * ST := (NR - E)
				 */
				st = tmp.tv_usec;
			}
			
			/*
			 * SLEEP(ST)
			 */
			usleep(st);
		}
	} while (0);

	return 0; /* buddha says i'll never be reached */
}