Only grab SIGHUP if we can do something with it.

adsbus/log.c

@@ -90,6 +90,7 @@ void log_init() {
 }
 
 void log_init_peer() {
+	if (log_path) {
 		sigset_t sigmask;
 		assert(!sigemptyset(&sigmask));
 		assert(!sigaddset(&sigmask, SIGHUP));
@@ -99,6 +100,9 @@ void log_init_peer() {
 		peer_epoll_add(&log_rotate_peer, EPOLLIN);
 
 		assert(!sigprocmask(SIG_BLOCK, &sigmask, NULL));
+	} else {
+		log_rotate_peer.fd = -1;
+	}
 }
 
 void log_cleanup_peer() {