Function sys_mq_open

components/lwp/lwp_syscall.c:9057–9102

* @brief Open a message queue. * * This function opens a message queue for communication between processes. * It can create a new message queue or open an existing one, depending on the specified * flags. * * @param[in] name The name of the message queue. The name should be a null-terminated * string and is subject to system-specific naming conventions. * @param[in] flags

 *       return `-1`.
 */
mqd_t sys_mq_open(const char *name, int flags, mode_t mode, struct mq_attr *attr)
{
    mqd_t mqdes;
    sysret_t ret = 0;
#ifdef ARCH_MM_MMU
    char *kname = RT_NULL;
    rt_size_t len = 0;
    struct mq_attr attr_k;

    len = lwp_user_strlen(name);
    if (!len)
        return (mqd_t)-EINVAL;

    kname = (char *)kmem_get(len + 1);
    if (!kname)
        return (mqd_t)-ENOMEM;

    if (attr == NULL)
    {
        attr_k.mq_maxmsg = 10;
        attr_k.mq_msgsize = 8192;
        attr_k.mq_flags = 0;
        attr = &attr_k;
    }
    else
    {
        if (!lwp_get_from_user(&attr_k, (void *)attr, sizeof(struct mq_attr)))
            return -EINVAL;
    }

    lwp_get_from_user(kname, (void *)name, len + 1);
    mqdes = mq_open(kname, flags, mode, &attr_k);
    if (mqdes == -1)
    {
        ret = GET_ERRNO();
    }
    lwp_put_to_user(attr, &attr_k, sizeof(struct mq_attr));
    kmem_put(kname);
#else
    mqdes = mq_open(name, flags, mode, attr);
#endif
    if (mqdes == -1)
        return (mqd_t)ret;
    else
        return mqdes;
}

/**
 * @brief Remove a message queue.