Function lwp_argscopy

components/lwp/lwp_args.c:310–388

* @brief Copy a light-weight process arguments info structure to user space * * @param[in] lwp Pointer to the light-weight process structure * @param[in] ai Pointer to the arguments info structure to copy * * @return struct process_aux* Pointer to the process auxiliary structure in user space */

 * @return struct process_aux* Pointer to the process auxiliary structure in user space
 */
struct process_aux *lwp_argscopy(struct rt_lwp *lwp, struct lwp_args_info *ai)
{
    int size = sizeof(rt_base_t) * 4; /* store argc, argv_NULL, envp_NULL, aux_NULL */
    char *str_ua;
    const char **args_ua;
    const char **iter;
    rt_base_t off;
    struct process_aux_item pa_item;
    struct process_aux *aux_ua;
    size_t prot = PROT_READ | PROT_WRITE;
    size_t flags = MAP_FIXED | MAP_PRIVATE;
    rt_base_t argc = ai->argv.string_count;
    rt_base_t envc = ai->envp.string_count;

    /**
     * counts the bytes to storage the args
     */
    size += argc * sizeof(char *) + envc * sizeof(char *)
        + ai->strings_length + sizeof(struct process_aux);

    args_ua = lwp_mmap2(lwp, (void *)(USER_STACK_VEND), size, prot, flags, -1, 0);
    if (args_ua == RT_NULL)
    {
        return RT_NULL;
    }

    /**
     * @brief Put data from args info to user space
     * argc, argv[], NULL, envp[], NULL, aux[], NULL, strings
     */
    iter = args_ua;

    /* argc */
    lwp_data_put(lwp, iter++, &argc, sizeof(char *));

    /* strings */
    str_ua = (char *)((rt_ubase_t)args_ua +
        (1 + argc + 1 + envc + 1 + AUX_ARRAY_ITEMS_NR * 2 + 1) * sizeof(rt_base_t));
    lwp_data_put(lwp, str_ua, ai->str_buf, ai->strings_length);

    /* argv */
    off = str_ua - ai->str_buf;
    for (size_t i = 0; i < argc; i++)
    {
        /* str_ua + ai->argv.strvec[i] - ai->str_buf */
        ai->argv.strvec[i] += off;
    }
    lwp_data_put(lwp, iter, ai->argv.strvec, sizeof(char *) * ai->argv.string_count);
    iter += ai->argv.string_count;

    /* NULL */
    lwp_data_set(lwp, iter++, 0, sizeof(char *));

    /* envp */
    for (size_t i = 0; i < envc; i++)
    {
        /* str_ua + ai->envp.strvec[i] - ai->str_buf */
        ai->envp.strvec[i] += off;