ntp_client.h

// Copyright 2024-2025 The Aerospace Corporation.
// This file is a part of SatCat5, licensed under CERN-OHL-W v2 or later.
// Client and/or server for the Network Time Protocol (NTP)
 
#pragma once
 
#include <satcat5/ntp_header.h>
#include <satcat5/polling.h>
#include <satcat5/ptp_source.h>
#include <satcat5/udp_core.h>
#include <satcat5/udp_dispatch.h>
 
namespace satcat5 {
    namespace ntp {
        class Client
            : public satcat5::net::Protocol
            , public satcat5::poll::Timer
            , public satcat5::ptp::Source
        {
        public:
            Client(
                satcat5::ptp::TrackingClock* refclk,
                satcat5::udp::Dispatch* iface);
            ~Client() SATCAT5_OPTIONAL_DTOR;
 
            void client_connect(
                const satcat5::ip::Addr& server,
                s8 poll_rate = satcat5::ntp::Header::TIME_1MIN);
 
            void client_close();
 
            inline bool client_ok()
                { return m_iface.ready(); }
 
            void client_set_rate(s8 poll_rate);
 
            inline void server_start(u8 stratum)
                { m_stratum = stratum; }
 
            u64 ntp_now() const;
            u64 to_ntp(const satcat5::ptp::Time& t) const;
            satcat5::ptp::Time to_ptp(u64 t) const;
 
        protected:
            // Inherited event handlers.
            void frame_rcvd(satcat5::io::LimitedRead& src) override;
            void timer_event() override;
 
            // Internal event handlers.
            void rcvd_reply(const satcat5::ntp::Header& msg, u64 rxtime);
            bool send_reply(const satcat5::ntp::Header& msg, u64 rxtime);
            bool send_query();
 
            // Internal state.
            satcat5::ptp::TrackingClock* const m_refclk;
            satcat5::udp::Address m_iface;
            u64 m_reftime;
            u8 m_leap;
            u8 m_stratum;
            s8 m_rate;
        };
    }
}