runtime_id_routing.c

int rt_id_routing(struct msu_type *type, struct local_msu *sender,
                  struct msu_msg *msg, struct msu_endpoint *output) {
    struct routing_table *table = get_type_from_route_set(&sender->routes, type->id);
    if (table == NULL) {
        log_error("No routes available from msu %d to type %s (%d)",
                  sender->id, type->name, type->id);
        return -1;
    }
    
    // Line MAX_ENDPOINTS could be replaced by a call to get_n_endpoints()
    struct msu_endpoint endpoints[MAX_ENDPOINTS];

    int n_endpoints = get_endpoints_by_runtime_id(table, RT_ID, endpoints, MAX_ENDPOINTS);
    if (n_endpoints <= 0) {
        log_error("No endpoints available on runtime %d", RT_ID);
        return -1;
    }

    // To choose a random one of the returned endpoints
    int idx = int(rand() * (n_endpoints - 1));
    // You could also use (msg->id % n_endpoints) if you wanted some
    // sort of consistency

    // Fill the output with the chosen endpoint
    *output = endpoints[idx];

    return 0;
}
...
struct msu_type MY_MSU_TYPE {
    .name = "My_MSU",
    ...
    .route = rt_id_routing
};

Hi Isaac,
For line 11, struct msu_endpoint endpoints[MAX_ENDPOINTS];, if it is guaranteed that there is only one msu of the specific type on the specific runtime, may I just create an array of length 1?
Thanks.
YZ