Method queryTxt

src/SFML/Network/Dns.cpp:797–890

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std::vector<std::vector<sf::String>> Dns::queryTxt(const String&                 hostname,
                                                   const std::vector<IpAddress>& servers,
                                                   std::optional<Time>           timeout)
{
    std::vector<std::vector<sf::String>> txtRecords;

    if (hostname.isEmpty())
        return txtRecords;

    auto encoded = encodeHostname(hostname);

    // On Android the libc provided resolv API doesn't work, we will have to do the work ourselves
#if defined(SFML_SYSTEM_ANDROID)
    const auto& serversToQuery = servers.empty() ? getAndroidServers() : servers;
#else
    const auto& serversToQuery = servers;
#endif

    if (!serversToQuery.empty())
    {
        queryDns(
            [&](const char* data, std::size_t length, const char*, std::uint16_t responseType, std::uint16_t responseClass)
            {
                // TXT, IN
                if ((responseType != 16) || (responseClass != 1))
                    return;

                auto&             list  = txtRecords.emplace_back();
                const auto*       begin = data;
                const auto* const end   = begin + length;
                std::string       buffer;
                buffer.reserve(length);

                while (begin < end)
                {
                    buffer.clear();
                    std::uint8_t txtLength{};
                    std::memcpy(&txtLength, begin++, 1);
                    for (auto i = 0u; (i < txtLength) && (begin < end); ++i)
                        buffer.push_back(*begin++);
                    if (!buffer.empty())
                        list.emplace_back(buffer);
                }
            },
            timeout,
            {{serversToQuery,
              16, // TXT
              1,  // IN
              encoded}});

        return txtRecords;
    }

#if defined(SFML_SYSTEM_WINDOWS)
    const auto records = getRecords(encoded, DNS_TYPE_TEXT);
    for (const auto* ptr = records.get(); ptr; ptr = ptr->pNext)
    {
        if (ptr->wType == DNS_TYPE_TEXT)