Method reset

test/read_at.cpp:51–63

  }

  void reset(const void* data, size_t length)
  {
    BOOST_ASIO_CHECK(length <= max_length);

    length_ = 0;
    while (length_ + length < max_length)
    {
      memcpy(data_ + length_, data, length);
      length_ += length;
    }

    next_read_length_ = length;
  }

  void next_read_length(size_t length)
  {