Function lwp_get_envp

components/lwp/lwp_args.c:900–962

* @brief Get environment variables of light-weight process * * @param[in] lwp Pointer to the light-weight process structure * @param[out] penvp_counts Pointer to store the number of environment variables * * @return char** Returns a NULL-terminated array of environment variable strings on success: * - The array and each string are allocated in kernel space * - The caller is

 *         RT_NULL Returns NULL on failure (invalid LWP, memory allocation failure, or copy error)
 */
char** lwp_get_envp(struct rt_lwp *lwp, rt_size_t *penvp_counts)
{
    int ret, len;
    rt_base_t argc;
    char **p_kenvp = RT_NULL;
    char *envp, **p_envp;
    size_t envp_counts = 0;

    if (lwp)
    {
        ret = lwp_data_get(lwp, &argc, lwp->args, sizeof(argc));
        if (ret == 0)
        {
            return RT_NULL;
        }
        p_envp = (char **)lwp->args + 1 + argc + 1;

        /* counts envp */
        while (lwp_data_get(lwp, &envp, p_envp, sizeof(void *)) == sizeof(void *)
               && envp != NULL)
        {
            p_envp++;
            envp_counts++;
        }

        p_kenvp = (char **)rt_malloc((envp_counts + 1) * sizeof(char *));
        if (p_kenvp)
        {
            /* copy env from envp array */
            p_envp =  (char **)lwp->args + 1 + argc + 1;
            for (size_t i = 0; i < envp_counts; i++)
            {
                ret = lwp_data_get(lwp, &envp, &p_envp[i], sizeof(char *));
                if (ret != sizeof(char **))
                {
                    lwp_free_command_line_args(p_kenvp);
                    return RT_NULL;
                }

                len = lwp_user_strlen_ext(lwp, envp);
                if (len > 0)
                {
                    p_kenvp[i] = (char*)rt_malloc(len + 1);
                    ret = lwp_data_get(lwp, p_kenvp[i], envp, len + 1);
                    if (ret != len + 1)
                    {
                        lwp_free_command_line_args(p_kenvp);
                        return RT_NULL;
                    }
                }
                else
                {
                    p_kenvp[i] = NULL;
                }
            }
            if (penvp_counts)
                *penvp_counts = envp_counts;
            p_kenvp[envp_counts] = NULL;