BufferReader(BufferReader const & src, uint64_t pos, uint64_t size)
: m_data(src.m_data)
{
ASSERT_LESS_OR_EQUAL(pos + size, src.Size(), (pos, size));
m_offset = static_cast<size_t>(src.m_offset + pos);
m_size = static_cast<size_t>(size);
}
