Function write_sector

arch/macintosh/encoder.cc:172–211

}

static void write_sector(std::vector<bool>& bits,
    unsigned& cursor,
    const std::shared_ptr<const Sector>& sector)
{
    if ((sector->data.size() != 512) && (sector->data.size() != 524))
        error("unsupported sector size --- you must pick 512 or 524");

    write_bits(bits, cursor, 0xff, 1 * 8); /* pad byte */
    for (int i = 0; i < 7; i++)
        write_bits(bits, cursor, 0xff3fcff3fcffLL, 6 * 8); /* sync */
    write_bits(bits, cursor, MAC_SECTOR_RECORD, 3 * 8);

    uint8_t encodedTrack = sector->logicalCylinder & 0x3f;
    uint8_t encodedSector = sector->logicalSector;
    uint8_t encodedSide =
        encode_side(sector->logicalCylinder, sector->logicalHead);
    uint8_t formatByte = MAC_FORMAT_BYTE;
    uint8_t headerChecksum =
        (encodedTrack ^ encodedSector ^ encodedSide ^ formatByte) & 0x3f;

    write_bits(bits, cursor, encode_data_gcr(encodedTrack), 1 * 8);
    write_bits(bits, cursor, encode_data_gcr(encodedSector), 1 * 8);
    write_bits(bits, cursor, encode_data_gcr(encodedSide), 1 * 8);
    write_bits(bits, cursor, encode_data_gcr(formatByte), 1 * 8);
    write_bits(bits, cursor, encode_data_gcr(headerChecksum), 1 * 8);

    write_bits(bits, cursor, 0xdeaaff, 3 * 8);
    write_bits(bits, cursor, 0xff3fcff3fcffLL, 6 * 8); /* sync */
    write_bits(bits, cursor, MAC_DATA_RECORD, 3 * 8);
    write_bits(bits, cursor, encode_data_gcr(sector->logicalSector), 1 * 8);

    Bytes wireData;
    wireData.writer()
        .append(sector->data.slice(512, 12))
        .append(sector->data.slice(0, 512));
    for (uint8_t b : encode_crazy_data(wireData))
        write_bits(bits, cursor, encode_data_gcr(b), 1 * 8);

    write_bits(bits, cursor, 0xdeaaff, 3 * 8);
}

class MacintoshEncoder : public Encoder
{