Struct ClientRecord 

pub struct ClientRecord {
    pub last_seen: f64,
    pub requests: u64,
    pub responses: u64,
    pub dropped: u64,
    pub last_receive: NtpTimestamp,
    pub last_transmit: NtpTimestamp,
    pub last_receive_sent: NtpTimestamp,
    pub interleaved_now: bool,
    /* private fields */
}

Per-client state: enough for rate limiting, interleaved mode and the MRU report, and no more — this is multiplied by every client that has ever spoken to us.

Fields

last_seen: f64

requests: u64

responses: u64

dropped: u64

last_receive: NtpTimestamp

T2 of the last request we accepted. NtpTimestamp::ZERO until there has been one.

Zero rather than Option deliberately: NtpTimestamp is a bare u64 with no niche, so Option<NtpTimestamp> is SIXTEEN bytes for eight bytes of payload and every read tests a discriminant. An all-zero timestamp is already how RFC 5905 spells “unset” on the wire, so the sentinel is the protocol’s own, not one invented here (rusty-compiler-leverage B5: the one win in that table was a representation change, not a bit trick).

last_transmit: NtpTimestamp

The true transmit timestamp of our last response, once the driver reports it. NtpTimestamp::ZERO until then, which is why interleaved mode cannot answer the very first request.

last_receive_sent: NtpTimestamp

The receive timestamp we put in our last response. A client asks for interleaved mode by echoing exactly this. NtpTimestamp::ZERO until we have answered once.

interleaved_now: bool

Whether the last answered request was actually served interleaved.

Distinct from “we could serve it interleaved”: every client we have answered once is capable, but only a client that asks is using it, and an operator reading a client log needs the second fact.

Trait Implementations

impl Clone for ClientRecord

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for ClientRecord

impl Debug for ClientRecord

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.