Enum ProtocolVersion

pub enum ProtocolVersion {
    V0,
    V1,
}

Protocol version. This can be extracted from the payload of the sync packet and will determine what features a connection supports.

Variants

V0

Protocol version 0

V1

Protocol version 1

Implementations

impl ProtocolVersion

pub const LATEST: ProtocolVersion = ProtocolVersion::V1

The latest protocol version.

pub fn magic(&self) -> &[u8]

Magic sent in the sync packet of the USB protocol.

The format is a byte string of the form vsock:0, where the 0 indicates protocol version 0, and we expect the reply sync packet to have the exact same contents. As we version the protocol this may increment.

To document the semantics, let’s say this header were “vsock:3”. The device could reply with a lower number, say “vsock:1”. This is the device requesting a downgrade, and if we accept we send the final sync with “vsock:1”. Otherwise we hang up.

pub fn from_magic(magic: &[u8]) -> Option<ProtocolVersion>

Derive the protocol version from the magic sent in the sync packet.

pub fn negotiate( &self, host_version: &ProtocolVersion, ) -> Option<ProtocolVersion>

Given self is the protocol version the target prefers and host_version is the protocol version sent in the magic as the host connects, find the protocol version that should be sent in the reply magic and used for the connection. If None, negotiation has broken down.

Trait Implementations

impl Clone for ProtocolVersion

fn clone(&self) -> ProtocolVersion

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Display for ProtocolVersion

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

Formats the value using the given formatter.

impl PartialEq for ProtocolVersion

fn eq(&self, other: &ProtocolVersion) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for ProtocolVersion

impl Eq for ProtocolVersion

impl StructuralPartialEq for ProtocolVersion