/* Unix only provides a single ALRM signal, so we use the same handler for
* frequent updates (every 5 seconds) and differential updates (every 30
* seconds). We trigger an ALRM every 5 seconds and only write differential
* updates every 6th ALRM. */
static void handle_signals(int sig) {
if (sig == SIGINT || sig == SIGTERM) {
write_update();
#ifdef ENABLE_FREQUENT_UPDATES
write_frequent_update();
#endif
exit(0);
} else if (sig == SIGALRM) {
alarm_count += 1;
if (alarm_count % ALARMS_PER_UPDATE == 0) {
#ifndef DISABLE_FLOW_THRESHOLDING
write_flow_log();
#endif
write_update();
}
#ifdef ENABLE_FREQUENT_UPDATES
write_frequent_update();
#endif
if (alarm_count % ALARMS_PER_UPDATE == 0
&& upload_failures_check(&upload_failures) > 0) {
exit(0);
}
set_next_alarm();
}
}
static void* frequent_updater(void* arg) {
while (1) {
sleep(FREQUENT_UPDATE_PERIOD_SECONDS);
if (pthread_mutex_lock(&update_lock)) {
perror("Error acquiring mutex for update");
exit(1);
}
write_frequent_update();
if (pthread_mutex_unlock(&update_lock)) {
perror("Error unlocking update mutex");
exit(1);
}
}
}
static void* handle_signals(void* arg) {
sigset_t* signal_set = (sigset_t*)arg;
int signal_handled;
while (1) {
if (sigwait(signal_set, &signal_handled)) {
perror("Error handling signal");
continue;
}
if (pthread_mutex_lock(&update_lock)) {
perror("Error acquiring mutex for update");
exit(1);
}
write_update();
#ifdef ENABLE_FREQUENT_UPDATES
write_frequent_update();
#endif
exit(0);
}
}