Only add/remove poll events when they aren't already done.

src/mux_poll.c

@@ -110,6 +110,7 @@ int mux_poll__add_out(struct mosquitto *context)
 {
 	int i;
 
+	if(!(context->events & POLLOUT)) {
 		if(context->pollfd_index != -1){
 			pollfds[context->pollfd_index].fd = context->sock;
 			pollfds[context->pollfd_index].events = POLLIN | POLLOUT;
@@ -128,6 +129,8 @@ int mux_poll__add_out(struct mosquitto *context)
 				}
 			}
 		}
+		context->events = POLLIN | POLLOUT;
+	}
 
 	return MOSQ_ERR_SUCCESS;
 }
@@ -135,7 +138,11 @@ int mux_poll__add_out(struct mosquitto *context)
 
 int mux_poll__remove_out(struct mosquitto *context)
 {
+	if(context->events & POLLOUT) {
 		return mux_poll__add_in(context);
+	}else{
+		return MOSQ_ERR_SUCCESS;
+	}
 }
 
 
@@ -161,6 +168,7 @@ int mux_poll__add_in(struct mosquitto *context)
 			}
 		}
 	}
+	context->events = POLLIN;
 
 	return MOSQ_ERR_SUCCESS;
 }