www.pudn.com > ntp.zip > ntp.h

//Representation of an NTP timestamp 
struct CNtpTimePacket 
{ 
  DWORD m_dwInteger; 
	DWORD m_dwFractional; 
}; 
 
//Helper class to encapulate NTP time stamps 
class CNtpTime 
{ 
public: 
//Constructors / Destructors 
  CNtpTime(); 
  CNtpTime(const CNtpTime& time); 
  CNtpTime(CNtpTimePacket& packet); 
  CNtpTime(const SYSTEMTIME& st); 
 
//General functions 
  CNtpTime& operator=(const CNtpTime& time); 
	double operator-(const CNtpTime& time) const; 
	CNtpTime operator+(const double& timespan) const; 
  operator SYSTEMTIME() const; 
  operator CNtpTimePacket() const; 
  operator unsigned __int64() const { return m_Time; }; 
  DWORD Seconds() const; 
  DWORD Fraction() const; 
 
//Static functions 
  static CNtpTime GetCurrentTime(); 
  static DWORD MsToNtpFraction(WORD wMilliSeconds); 
  static WORD NtpFractionToMs(DWORD dwFraction); 
	static double NtpFractionToSecond(DWORD dwFraction); 
 
protected: 
//Internal static functions and data 
  static long GetJulianDay(WORD Year, WORD Month, WORD Day); 
  static void GetGregorianDate(long JD, WORD& Year, WORD& Month, WORD& Day); 
  static DWORD m_MsToNTP[1000]; 
 
//The actual data 
  unsigned __int64 m_Time; 
}; 
 
struct NtpServerResponse 
{ 
  int m_nLeapIndicator; //0: no warning 
                        //1: last minute in day has 61 seconds 
                        //2: last minute has 59 seconds 
                        //3: clock not synchronized 
 
  int m_nStratum; //0: unspecified or unavailable 
                  //1: primary reference (e.g., radio clock) 
                  //2-15: secondary reference (via NTP or NTP) 
                  //16-255: reserved 
 
  CNtpTime     m_OriginateTime;    //Time when the request was sent from the client to the NTP server 
  CNtpTime     m_ReceiveTime;      //Time when the request was received by the server 
  CNtpTime     m_TransmitTime;     //Time when the server sent the request back to the client 
  CNtpTime     m_DestinationTime;  //Time when the reply was received by the client 
  double       m_RoundTripDelay;   //Round trip time in seconds 
  double       m_LocalClockOffset; //Local clock offset relative to the server 
}; 
                   
//The actual NTP class 
class CNTPClient /////: public CObject 
{ 
public: 
	BOOL IsReadible(BOOL& bReadible, DWORD dwTimeout); 
//Constructors / Destructors 
  CNTPClient(); 
 
//General functions 
  BOOL  GetServerTime(LPCTSTR pszHostName, NtpServerResponse& response, int nPort = 123); 
  void  SetTimeout(DWORD dwTimeout) { m_dwTimeout = dwTimeout; }; 
  BOOL  SetClientTime(const CNtpTime& NewTime); 
 
protected: 
  BOOL EnableSetTimePriviledge(); 
  void RevertSetTimePriviledge(); 
  SOCKET m_hSocket; 
  DWORD            m_dwTimeout; 
  HANDLE           m_hToken; 
  TOKEN_PRIVILEGES m_TokenPriv; 
  BOOL             m_bTakenPriviledge; 
};