CascadeSNTPClient.h

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// CascadeSNTPClient.h : interface of class CascadeSNTPClient
//
// Copyright (c) 2005, Roku, LLC.  All rights reserved.
//

#ifndef _ROKU_INCLUDE_CASCADE_NET_CASCADESNTPCLIENT_H
#define _ROKU_INCLUDE_CASCADE_NET_CASCADESNTPCLIENT_H

#include <cascade/CascadeObject.h>
#include <cascade/util/CascadeTime.h>

// class CascadeSNTPClient - an easy to use socket for client connections
class CascadeSNTPClient : public CascadeObject
{
#ifndef DOXY_SKIP
public:
    struct InternetTimeStruct;
#endif
    
public:
    CascadeSNTPClient();
    virtual ~CascadeSNTPClient();

public:
    enum { kDefaultTimeout = 5000 };
    bool FetchInternetTime(const char * pServerName, InternetTimeStruct & timeStructToSet, u32 nTimeoutMS = kDefaultTimeout);
    
public:
    struct TimeStamp
    {
    public:
        inline bool operator == (const TimeStamp & that) const { return ((m_seconds == that.m_seconds) && (m_fractional == that.m_fractional)) ? true : false; }
        inline bool operator != (const TimeStamp & that) const { return ((m_seconds != that.m_seconds) || (m_fractional != that.m_fractional)) ? true : false; }
    public:
        unsigned long m_seconds;
        unsigned long m_fractional;
    };
    
    struct Packet
    {
    public:
        unsigned char m_flags;
        unsigned char m_stratum;
        unsigned char m_poll;
        unsigned char m_precision;
        unsigned long m_rootDelay;
        unsigned long m_rootDispersion;
        unsigned long m_refID;
        TimeStamp     m_refTimeStamp;
        TimeStamp     m_originateTimeStamp;
        TimeStamp     m_receiveTimeStamp;
        TimeStamp     m_transmitTimeStamp;      
    };
    
    struct InternetTimeStruct
    {
    public:
        CascadeTime::TimeBase m_timeBase;
            // the interesting part: you can use m_timeBase in a call
            // to CascadeTime::SetSystemClockTimeBase()
            // to set the system clock time based on this InternetTimeStruct
            // you probably should gather more than one of these
            // from different servers, normalize their time bases and
            // average them before so doing.  In practice, I, RokuDon, will
            // do this from a daemon in the Cascade process so don't actually
            // call CascadeTime::SetSystemClockTimeBase() because my daemon will overwrite
            // you at some point in the future!
        u32 m_nRoundTripDelayMilliseconds;
            // calculated RoundTrip delay in milliseconds
        Packet m_packetSent;
            // the entire SNTP packet that was sent should you care to examine
        Packet m_packetReceived;
            // the entire SNTP packet that was received should you care to examine
    };
    
    enum
    {
        kFlagsLeapIndicatorMask     = 0xC0,
        kFlagsLeapIndicatorNone     = 0x00,
        kFlagsLeapIndicatorLong     = 0x40,
        kFlagsLeapIndicatorShort    = 0x80,
        kFlagsLeapIndicatorAlarm    = 0xC0,
        kFlagsVersionMask           = 0x38,
        kFlagsVersion1              = 0x08,
        kFlagsVersion2              = 0x10,
        kFlagsVersion3              = 0x18,
        kFlagsModeMask              = 0x07,
        kFlagsModeActive            = 0x01,
        kFlagsModePassive           = 0x02,
        kFlagsModeClient            = 0x03,
        kFlagsModeServer            = 0x04,
        kFlagsModeBroadcast         = 0x05,
        kFlagsModeControl           = 0x06,
    };
    
private:
    class Client;
    Client * m_pClient;
};

#endif // #ifndef _ROKU_INCLUDE_CASCADE_NET_CASCADESNTPCLIENT_H

//      LOG 
//  18-May-05   dwoodward   created

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