+int main_loop(void) {
+ fd_set readset, writeset;
+#ifdef HAVE_PSELECT
+ struct timespec tv;
+ sigset_t omask, block_mask;
+ time_t next_event;
+#else
+ struct timeval tv;
+#endif
+ int r, maxfd;
+ time_t last_ping_check, last_config_check, last_graph_dump;
+ event_t *event;
+
+ last_ping_check = now;
+ last_config_check = now;
+ last_graph_dump = now;
+
+ srand(now);
+
+#ifdef HAVE_PSELECT
+
+ if(lookup_config(config_tree, "GraphDumpFile")) {
+ graph_dump = true;
+ }
+
+ /* Block SIGHUP & SIGALRM */
+ sigemptyset(&block_mask);
+ sigaddset(&block_mask, SIGHUP);
+ sigaddset(&block_mask, SIGALRM);
+ sigprocmask(SIG_BLOCK, &block_mask, &omask);
+#endif
+
+ running = true;
+
+ while(running) {
+#ifdef HAVE_PSELECT
+ next_event = last_ping_check + pingtimeout;
+
+ if(graph_dump && next_event > last_graph_dump + 60) {
+ next_event = last_graph_dump + 60;
+ }
+
+ if((event = peek_next_event()) && next_event > event->time) {
+ next_event = event->time;
+ }
+
+ if(next_event <= now) {
+ tv.tv_sec = 0;
+ } else {
+ tv.tv_sec = next_event - now;
+ }
+
+ tv.tv_nsec = 0;
+#else
+ tv.tv_sec = 1;
+ tv.tv_usec = 0;
+#endif
+
+ maxfd = build_fdset(&readset, &writeset);
+
+#ifdef HAVE_MINGW
+ LeaveCriticalSection(&mutex);
+#endif
+#ifdef HAVE_PSELECT
+ r = pselect(maxfd + 1, &readset, &writeset, NULL, &tv, &omask);
+#else
+ r = select(maxfd + 1, &readset, &writeset, NULL, &tv);
+#endif
+ now = time(NULL);
+#ifdef HAVE_MINGW
+ EnterCriticalSection(&mutex);
+#endif
+
+ if(r < 0) {
+ if(!sockwouldblock(sockerrno)) {
+ logger(LOG_ERR, "Error while waiting for input: %s", sockstrerror(sockerrno));
+ dump_connections();
+ return 1;
+ }
+ }
+
+ if(r > 0) {
+ check_network_activity(&readset, &writeset);
+ }
+
+ if(do_purge) {
+ purge();
+ do_purge = false;
+ }
+
+ /* Let's check if everybody is still alive */
+
+ if(last_ping_check + pingtimeout <= now) {
+ check_dead_connections();
+ last_ping_check = now;
+
+ if(routing_mode == RMODE_SWITCH) {
+ age_subnets();
+ }
+
+ age_past_requests();
+
+ /* Should we regenerate our key? */
+
+ if(keyexpires <= now) {
+ avl_node_t *node;
+ node_t *n;
+
+ ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys");
+
+ for(node = node_tree->head; node; node = node->next) {
+ n = node->data;
+
+ if(n->inkey) {
+ free(n->inkey);
+ n->inkey = NULL;
+ }
+ }
+
+ send_key_changed();
+ keyexpires = now + keylifetime;
+ }
+
+ /* Detect ADD_EDGE/DEL_EDGE storms that are caused when
+ * two tinc daemons with the same name are on the VPN.
+ * If so, sleep a while. If this happens multiple times
+ * in a row, sleep longer. */
+
+ if(contradicting_del_edge > 100 && contradicting_add_edge > 100) {
+ logger(LOG_WARNING, "Possible node with same Name as us! Sleeping %d seconds.", sleeptime);
+ usleep(sleeptime * 1000000LL);
+ sleeptime *= 2;