static enum imds_token_copy_result s_copy_token_safely()

in source/aws_imds_client.c [786:850]

• 58 lines of code
• 9 McCabe index (conditional complexity)

static enum imds_token_copy_result s_copy_token_safely(struct imds_user_data *user_data) {
    struct aws_imds_client *client = user_data->client;
    enum imds_token_copy_result ret = AWS_IMDS_TCR_UNEXPECTED_ERROR;

    struct aws_linked_list pending_queries;
    aws_linked_list_init(&pending_queries);
    aws_mutex_lock(&client->token_lock);

    if (client->token_state == AWS_IMDS_TS_VALID) {
        aws_byte_buf_reset(&user_data->imds_token, true);
        struct aws_byte_cursor cursor = aws_byte_cursor_from_buf(&client->cached_token);
        if (aws_byte_buf_append_dynamic(&user_data->imds_token, &cursor)) {
            ret = AWS_IMDS_TCR_UNEXPECTED_ERROR;
        } else {
            ret = AWS_IMDS_TCR_SUCCESS;
        }
    } else {
        ret = AWS_IMDS_TCR_WAITING_IN_QUEUE;
        struct imds_token_query *query = aws_mem_calloc(client->allocator, 1, sizeof(struct imds_token_query));
        if (query != NULL) {
            query->user_data = user_data;
            aws_linked_list_push_back(&client->pending_queries, &query->node);
        } else {
            ret = AWS_IMDS_TCR_UNEXPECTED_ERROR;
        }

        if (client->token_state == AWS_IMDS_TS_INVALID) {
            if (s_client_start_query_token(client)) {
                ret = AWS_IMDS_TCR_UNEXPECTED_ERROR;
                aws_linked_list_swap_contents(&pending_queries, &client->pending_queries);
            } else {
                client->token_state = AWS_IMDS_TS_UPDATE_IN_PROGRESS;
            }
        }
    }
    aws_mutex_unlock(&client->token_lock);

    s_complete_pending_queries(client, &pending_queries, true, NULL);

    switch (ret) {
        case AWS_IMDS_TCR_SUCCESS:
            AWS_LOGF_DEBUG(
                AWS_LS_IMDS_CLIENT,
                "(id=%p) IMDS client copied token to requester %p successfully.",
                (void *)client,
                (void *)user_data);
            break;

        case AWS_IMDS_TCR_WAITING_IN_QUEUE:
            AWS_LOGF_DEBUG(
                AWS_LS_IMDS_CLIENT, "(id=%p) IMDS client's token is invalid and is now updating.", (void *)client);
            break;

        case AWS_IMDS_TCR_UNEXPECTED_ERROR:
            AWS_LOGF_DEBUG(
                AWS_LS_IMDS_CLIENT,
                "(id=%p) IMDS client encountered unexpected error when processing token query for requester %p, error: "
                "%s.",
                (void *)client,
                (void *)user_data,
                aws_error_str(aws_last_error()));
            break;
    }
    return ret;
}