Function sys_mq_create

components/lwp/lwp_syscall.c:2590–2628

* @brief Creates a message queue. * * This system call creates a new message queue with a specified name, message size, * maximum number of messages, and associated flags. The message queue allows * messages of a given size to be sent and received between tasks or threads. * * @param[in] name The name of the message queue. It should be a unique * identifier and a

 *          `max_msgs` may lead to resource exhaustion.
 */
rt_mq_t sys_mq_create(const char *name,
                     rt_size_t   msg_size,
                     rt_size_t   max_msgs,
                     rt_uint8_t  flag)
{
    rt_mq_t mq = RT_NULL;

    int len = 0;
    char *kname = RT_NULL;

    len = lwp_user_strlen(name);
    if (len <= 0)
    {
        return RT_NULL;
    }

    kname = (char *)kmem_get(len + 1);
    if (!kname)
    {
        return RT_NULL;
    }

    if (lwp_get_from_user(kname, (void *)name, len + 1) != (len + 1))
    {
        kmem_put(kname);
        return RT_NULL;
    }

    mq = rt_mq_create(kname, msg_size, max_msgs, flag);
    if (lwp_user_object_add(lwp_self(), (rt_object_t)mq) != 0)
    {
        rt_mq_delete(mq);
        mq = NULL;
    }

    kmem_put(kname);

    return mq;
}

/**
 * @brief Deletes a message queue.