Struct Bvll6Frame 

pub struct Bvll6Frame<'a> {
    pub function: Bvlc6Function,
    pub payload: &'a [u8],
}

A B/IPv6 BVLL message whose header checks out, before its payload is read.

Bvll6Frame::decode checks the BVLC type and the Length field and accepts any function code, so a receiver can see a function it doesn’t know before Bvll6Frame::message reads the payload by the function’s layout.

Fields

function: Bvlc6Function

The function octet.

payload: &'a [u8]

The octets after the 4-octet header, from the first VMAC on.

Implementations

impl<'a> Bvll6Frame<'a>

pub fn decode(datagram: &'a [u8]) -> Result<Self, Bvll6Error>

Check a datagram’s BVLL header and split off its payload.

The datagram must be one whole message: at least the 4-octet header, BVLC type 0x82, and a Length field equal to the datagram’s length, since it counts the whole message (Annex U.2). Octets after the declared length are refused rather than ignored, so a datagram can’t pass for a shorter message.

use bacnet_bip_codec::ipv6::{Bvlc6Function, Bvll6Error, Bvll6Frame};

// A Virtual-Address-Resolution from VMAC 00 04 D2.
let frame = Bvll6Frame::decode(&[0x82, 0x06, 0x00, 0x07, 0x00, 0x04, 0xD2])?;
assert_eq!(frame.function, Bvlc6Function::VIRTUAL_ADDRESS_RESOLUTION);
assert_eq!(frame.payload, [0x00, 0x04, 0xD2]);

// Function 0x0B still has a frame, but no message.
let frame = Bvll6Frame::decode(&[0x82, 0x0B, 0x00, 0x07, 0x00, 0x04, 0xD2])?;
assert_eq!(frame.message(), Err(Bvll6Error::UnknownFunction { function: 0x0B }));

// A trailing octet the Length field doesn't count.
assert_eq!(
    Bvll6Frame::decode(&[0x82, 0x06, 0x00, 0x07, 0x00, 0x04, 0xD2, 0x00]),
    Err(Bvll6Error::LengthMismatch { declared: 7, received: 8 }),
);

pub fn message(self) -> Result<Bvll6<'a>, Bvll6Error>

Read the payload by the function’s layout (see Bvlc6Function::payload_shape).

Fails with Bvll6Error::UnknownFunction for a function Annex U doesn’t define, and with Bvll6Error::PayloadLength when the payload is the wrong length for its function. Field values are not judged: any VMAC or address, an undefined result code, a zero time-to-live and an empty NPDU all decode.

Trait Implementations

impl<'a> Clone for Bvll6Frame<'a>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Copy for Bvll6Frame<'a>

impl<'a> Debug for Bvll6Frame<'a>

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

Formats the value using the given formatter.

impl<'a> Eq for Bvll6Frame<'a>

impl<'a> PartialEq for Bvll6Frame<'a>

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

Equality operator ==.

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

Inequality operator !=.

impl<'a> StructuralPartialEq for Bvll6Frame<'a>