Function decodeBase64

include/engine/base64.hpp:101–113

// Decodes into a chunk of memory that is at least as large as the input.
template <typename OutputIter> void decodeBase64(const std::string &encoded, OutputIter out)
{
    auto unpadded = encoded;

    const auto num_padded = std::count(begin(encoded), end(encoded), '=');
    std::replace(begin(unpadded), end(unpadded), '=', 'A'); // A_64 == \0

    std::string decoded{detail::BinaryFromBase64{begin(unpadded)},
                        detail::BinaryFromBase64{begin(unpadded) + unpadded.length()}};

    decoded.erase(end(decoded) - num_padded, end(decoded));
    std::copy(begin(decoded), end(decoded), out);
}

// Convenience specialization, filling string instead of byte-dumping into it.
inline std::string decodeBase64(const std::string &encoded)