Function rt_link_dev_read

components/utilities/rt-link/src/rtlink_dev.c:268–306

}

rt_ssize_t rt_link_dev_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
{
    RT_ASSERT(dev != RT_NULL);
    RT_ASSERT(buffer != RT_NULL);
    RT_ASSERT(size != 0);

    struct rt_link_device *rtlink = (struct rt_link_device *)dev;
    struct rtlink_recv_list *node;
    rt_size_t read_len = 0;
    rt_size_t unread_len = 0;

    if (dev->rx_indicate == RT_NULL)
    {
        /* RT_LINK_RX_BLOCKING, wait service receive data event */
        rt_link_event_recv(&rtlink->service);
    }

    if (rt_slist_first(&rtlink->recv_head) != RT_NULL)
    {
        node = rt_container_of(rt_slist_next(&rtlink->recv_head), struct rtlink_recv_list, list);
        unread_len = (node->size) - (node->index);
        read_len = (size > unread_len) ? unread_len : size;
        rt_memcpy(buffer, (rt_uint8_t *)node->data + node->index, read_len);
        node->index += read_len;

        if (node->index >= node->size)
        {
            rt_slist_remove(&rtlink->recv_head, &node->list);
            node->index = 0;
            rt_free(node->data);
            rt_free(node);
        }
        if (rt_slist_first(&rtlink->recv_head) != RT_NULL)
        {
            rt_link_event_send(&rtlink->service);
        }
    }
    return read_len;
}

rt_ssize_t rt_link_dev_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
{