Method initialize

io/QfitReader.cpp:203–265

void QfitReader::initialize()
{
    ISwitchableStream str(m_filename);
    if (!str)
        throwError("Unable to open file '" + m_filename + "'");
    str.seek(0);

    int32_t int4(0);

    str >> int4;

    // They started writting little-endian data->

    /* For years we produced ATM data in big-endian format. With changes in
    computer hardware, we reluctantly changed our standard output to
    little-endian. The transition occurred between the two 2010 campaigns. The
    format of the binary ( .qi, for example) files can be identified by
    examining the first four bytes of the file. Read as a long integer (one
    4-byte word), the value will contain the record length (in bytes) of the
    data records. For example, a .qi file containing 14 words per record will
    have a value 56 (=4*14). If the format of the file matches the format of
    your processor, the value will be reasonable without byte-swapping. If the
    format of the file differs from your processor, then the value is
    interpreted as some very large number, unless you swap the byte order. If
    you use Intel or equivalent processors, then you had to byte-swap files
    from spring 2010 and earlier, you do not swap the ones from fall 2010 and
    later. */

    // If the size comes back something other than 4*no_dimensions, we assume
    // The data were flipped
    if (int4 < 100)
    {
        m_littleEndian = true;
    }
    else
    {
        str.switchToBigEndian();
    }

    if (!m_littleEndian)
        int4 = int32_t(be32toh(uint32_t(int4)));

    if (int4 % 4 != 0)
        throwError("Base QFIT format is not a multiple of 4, "
            "unrecognized format!");

    m_size = int4;
    m_format = static_cast<QFIT_Format_Type>(m_size / sizeof(m_size));

    // The offset to start reading point data should be here.
    str.seek(m_size + sizeof(int4));

    str >> int4;
    m_offset = static_cast<std::size_t>(int4);

    // Seek to the end
    str.seek(0, std::istream::end);
    std::ios::pos_type end = str.position();