get sid from sessionid

bool get_sid_from_session_id(__out LPTSTR &string_sid, __in DWORD session_number)
{
    bool result = false;
    HANDLE current_user_handle = nullptr;
 
    do
    {
        if (FALSE == WTSQueryUserToken(session_number, current_user_handle))
        {            
            break;
        }
 
        DWORD dwSize = 0;
        BYTE * token_information = nullptr;
        if (FALSE == GetTokenInformation(current_user_handle, TokenUser, 
            static_cast<LPVOID>(token_information), 0, &dwSize))
        {
            if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
            {
                token_information = new(std::nothrow) BYTE[dwSize];
                if(nullptr == token_information)
                {
                    break;
                }
 
                ::memset(token_information, 0, dwSize);
            }
            else
            {                
                break;
            }
        }
 
        PTOKEN_USER token_user = reinterpret_cast<PTOKEN_USER>(token_information);
        if (FALSE == GetTokenInformation(current_user_handle, TokenUser, 
            static_cast<LPVOID>(token_user), dwSize, &dwSize))
        {            
            break;
        }
 
        if (FALSE == ConvertSidToStringSid(token_user->User.Sid, &string_sid))
        {            
            break;
        }
 
        if (nullptr != string_sid)
        {
            result = true;
        }
 
    } while (false);
 
    if (nullptr != current_user_handle)
        CloseHandle(current_user_handle);
    current_user_handle = nullptr;
 
    return result;
}

__out 의 string_sid는 ::LocalFree를 해야함.

https://msdn.microsoft.com/ko-kr/library/windows/desktop/aa376399%28v=vs.85%29.aspx