void Lex_input_stream::body_utf8_append(const char *ptr,
                                        const char *end_ptr)
{
  DBUG_ASSERT(m_cpp_buf <= ptr && ptr <= m_cpp_buf + m_buf_length);
  DBUG_ASSERT(m_cpp_buf <= end_ptr && end_ptr <= m_cpp_buf + m_buf_length);

  if (!m_body_utf8)
    return;

  if (m_cpp_utf8_processed_ptr >= ptr)
    return;

  size_t bytes_to_copy= ptr - m_cpp_utf8_processed_ptr;

  memcpy(m_body_utf8_ptr, m_cpp_utf8_processed_ptr, bytes_to_copy);
  m_body_utf8_ptr += bytes_to_copy;
  *m_body_utf8_ptr= 0;

  m_cpp_utf8_processed_ptr= end_ptr;
}