Struct SubgroupObjectMeta 

pub struct SubgroupObjectMeta {
    pub object_id: u64,
    pub extension_headers_len: u64,
    pub payload_length: u64,
    pub status: Option<u64>,
    pub wire_len: u64,
}

The framing of one draft-17 subgroup object, without its payload.

Produced by SubgroupObjectReader::read_object_meta for callers that forward an object’s bytes verbatim and never inspect the payload.

Fields

object_id: u64

Resolved absolute Object ID.

extension_headers_len: u64

Byte length of the properties block’s contents, excluding its length prefix.

payload_length: u64

Declared payload length. Zero when status is Some.

status: Option<u64>

Object status wire code, present only when the payload is empty.

wire_len: u64

Total bytes this object occupies on the wire, prefix fields included.

Implementations

impl SubgroupObjectMeta

pub fn payload_permission(&self) -> Option<PayloadPermission>

Whether this object’s stated status allows it a non-empty payload.

None when the object states no status at all. On a subgroup stream that is every object that carries bytes: draft-17 Section 10.4.2 puts the status field on the wire only when the Object Payload Length is zero, and Section 10.2.1.1 says Normal “is implicit for any non-zero length object”. An absent status is therefore not an unknown one — it is Normal, spelled by the payload’s own presence — but it is not a stated permission, and this method reports only what the object states.

Some otherwise, reading draft-17 Section 10.2.1.1’s rule off the code: “Any object with a status code other than zero MUST have an empty payload.” Zero permits, everything else forbids, which holds for codes beyond the three the draft assigns as well — the rule is arithmetic, not a lookup, so it does not go stale if a later draft assigns more.

Worth having even though a stated status here always sits beside a zero payload length, because the framing is not the destination. A caller forwarding this object onto a datagram, where the payload is whatever follows the header rather than a counted field, needs to know the object may not be given bytes there either; the length it read on this stream says nothing about that.

Trait Implementations

impl Clone for SubgroupObjectMeta

fn clone(&self) -> SubgroupObjectMeta

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SubgroupObjectMeta

impl Debug for SubgroupObjectMeta

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

Formats the value using the given formatter.

impl Eq for SubgroupObjectMeta

impl PartialEq for SubgroupObjectMeta

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for SubgroupObjectMeta