const Parameters::CaptureParams Parameters::capture_params()

in src/controller/parameters.cpp [288:342]

• 44 lines of code
• 8 McCabe index (conditional complexity)

const Parameters::CaptureParams Parameters::capture_params() const
{
    Parameters::CaptureParams params;
    params.interface   = impl->get(CLI::ArgInterface);
    params.filter      = impl->get(CLI::ArgFilter);
    params.snaplen     = impl->get(CLI::ArgSnaplen).to_int();
    params.timeout_ms  = impl->get(CLI::ArgTimeout).to_int();
    params.buffer_size = impl->get(CLI::ArgBSize).to_int() * 1024 * 1024; // MBytes
    params.promisc     = impl->get(CLI::ArgPromisc).to_bool();

    // check interface
    if(impl->is_default(CLI::ArgInterface))
    {
        params.interface = NST::filtration::pcap::NetworkInterfaces::default_device();
    }

    // check capture buffer size
    if(params.buffer_size < 1024 * 1024) // less than 1 MBytes
    {
        throw cmdline::CLIError{std::string{"Invalid value of kernel buffer size: "} + impl->get(CLI::ArgBSize).to_cstr()};
    }

    // check max length of raw captured UDP packet
    if(params.snaplen < 1 || params.snaplen > 65535)
    {
        throw cmdline::CLIError{std::string{"Invalid value of max length of raw captured UDP packet: "} + impl->get(CLI::ArgSnaplen).to_cstr()};
    }

    // check the read timeout that will be used on a capture
    if(params.timeout_ms < 1)
    {
        throw cmdline::CLIError{std::string{"Invalid value of read timeout that will be used on a capture: "} + impl->get(CLI::ArgTimeout).to_cstr()};
    }

    // check and set capture direction
    const auto& direction = impl->get(CLI::ArgDirection);
    if(direction.is("in"))
    {
        params.direction = decltype(params.direction)::IN;
    }
    else if(direction.is("out"))
    {
        params.direction = decltype(params.direction)::OUT;
    }
    else if(direction.is("inout"))
    {
        params.direction = decltype(params.direction)::INOUT;
    }
    else
    {
        throw cmdline::CLIError{std::string{"Unknown capturing direction: "} + direction.to_cstr()};
    }

    return params;
}