Same settings for the administrator account

[TymianekPL]

Description of the feature, modification, idea or suggestion

Recently Windows has introduced the Administrator Protection feature that basically creates a new account for the administrator named ADMIN_. I would like the settings to be shared with such configuration, as that's ideal.

Proposed implementation details (optional)

Check for Administrator Protection when running as admin, if that's the case, look for a username that's the part of the ADMIN_. I am unsure whether there exists an API to check that. This solution is not great, which is why I am not making a PR for this until I find a better solution.

[TymianekPL]

#ifdef UNICODE
using String = std::wstring;
#else
using String = std::string;
#endif

String GetRealUsername(void)
{
	HANDLE token = nullptr;
	if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &token))
		return L"";

	DWORD size = 0;
	GetTokenInformation(token, TokenLinkedToken, nullptr, 0, &size);
	if (size == 0)
	{
		CloseHandle(token);
		return L"";
	}

	std::unique_ptr<std::byte[]> buffer = std::make_unique_for_overwrite<std::byte[]>(size);
	if (!GetTokenInformation(token, TokenLinkedToken, buffer.get(), size, &size))
	{
		CloseHandle(token);
		return L"";
	}

	TOKEN_LINKED_TOKEN& linked = *std::launder(reinterpret_cast<TOKEN_LINKED_TOKEN*>(buffer.get()));
	HANDLE linkedToken = linked.LinkedToken;

	TCHAR name[256];
	TCHAR domain[256];
	DWORD nameLen = 256;
	DWORD domainLen = 256;
	SID_NAME_USE use;

	size = 0;
	GetTokenInformation(linkedToken, TokenUser, nullptr, 0, &size);
	auto userBuffer = std::make_unique_for_overwrite<std::byte[]>(size);
	if (!GetTokenInformation(linkedToken, TokenUser, userBuffer.get(), size, &size))
	{
		CloseHandle(linkedToken);
		CloseHandle(token);
		return L"";
	}

	auto& tokenUser = *std::launder(reinterpret_cast<TOKEN_USER*>(userBuffer.get()));

	if (!LookupAccountSid(nullptr, tokenUser.User.Sid, name, &nameLen, domain, &domainLen, &use))
	{
		CloseHandle(linkedToken);
		CloseHandle(token);
		return L"";
	}

	CloseHandle(linkedToken);
	CloseHandle(token);

	return std::wstring{ domain } + L"\\" + name;
}

That seems to work for administrator account (returns the real username)
Funny enough it returns the administrator account name when NOT ran as administrator, but that should not be an issue as elevation detection is trivial to implement