关于mqtt_subscribe的topic_filter指针问题

[youcanplay]

在阅读源码时，发现mqtt_subscribe()函数里的msg_handler->topic_filter指针指向的是形参的地址，而没有保存完整的字符串内容。
如果topic_filter传入的是一个局部变量指向的缓冲区，调用mqtt_subscribe是不是会有问题？

int mqtt_subscribe(mqtt_client_t* c, const char* topic_filter, mqtt_qos_t qos, message_handler_t handler)
{
//.......
    /* create a message and record it */
    msg_handler = mqtt_msg_handler_create(topic_filter, qos, handler);
    if (NULL == msg_handler) {
        rc = MQTT_MEM_NOT_ENOUGH_ERROR;
        goto exit;
    }
//.......

}


static message_handlers_t *mqtt_msg_handler_create(const char* topic_filter, mqtt_qos_t qos, message_handler_t handler)
{
    message_handlers_t *msg_handler = NULL;

    msg_handler = (message_handlers_t *) platform_memory_alloc(sizeof(message_handlers_t));
    if (NULL == msg_handler)
        return NULL;
    
    mqtt_list_init(&msg_handler->list);
    
    msg_handler->qos = qos;
    msg_handler->handler = handler;     /* register  callback handler */
    msg_handler->topic_filter = topic_filter;    //这里仅保存了传入的指针，而没有保存完整的字符串内容。

    return msg_handler;
}