Struct SubgroupObjectReader 

pub struct SubgroupObjectReader {
    extensions_present: bool,
    prev_object_id: Option<u64>,
    group_id: u64,
    group_gap: Option<u64>,
}

Stateful reader/writer for draft-16 subgroup objects. Mirrors the draft-15 semantics (delta-encoded object IDs and header-typed extension presence).

Fields

extensions_present: bool

prev_object_id: Option<u64>

group_id: u64

group_gap: Option<u64>

Implementations

impl SubgroupObjectReader

pub fn new(header: &SubgroupHeader) -> Self

pub fn read_object( &mut self, buf: &mut impl Buf, ) -> Result<SubgroupObject, CodecError>

Decode the next object whole, payload included.

Refuses, with CodecError::InvalidField, extension headers on an object whose status is not Normal: Section 10.2.1.2, “If an endpoint receives extension headers on Objects with status that is not Normal, it MUST close the session with a PROTOCOL_VIOLATION.” Self::read_object_meta frames such an object without judging it.

Refuses, with CodecError::MalformedTrack, the Prior Group ID Gap and Prior Object ID Gap conditions of Section 11.3 and Section 11.4 this stream shows: those PriorGaps::from_properties refuses, and “A Group contains more than one Object with different values for Prior Group ID Gap”. It does not refuse “An endpoint receives an Object with a Prior Object ID Gap covering an Object it previously received”: draft-16 Section 2.1 says of an Object known to exist, “From this state, it can transition to not existing, but not vice versa”, so whether such a gap makes the Track malformed is ambiguous. Self::read_object_meta does not read extension headers and applies none of them.

fn check_stream_gaps(&mut self, gaps: PriorGaps) -> Result<(), CodecError>

pub fn read_object_meta( &mut self, buf: &mut impl Buf, ) -> Result<SubgroupObjectMeta, CodecError>

Decode the next object’s framing without copying its payload.

Consumes exactly the bytes Self::read_object consumes and leaves the same delta state behind, so the two are interchangeable on a given stream.

pub fn write_object( &mut self, object: &SubgroupObject, buf: &mut impl BufMut, ) -> Result<(), CodecError>

Serialize an object, producing the correct delta encoding.

Errors with CodecError::InvalidField when object.object_id is not strictly greater than the previously written object’s ID, since no valid delta exists for that case.

A zero payload_length makes this a status object, and the status field is then mandatory on the wire: an absent SubgroupObject::object_status is written as ObjectStatus::Normal. The code written is always one draft-16 assigns, because the field cannot hold any other, so the bytes this produces are always bytes SubgroupObjectReader::read_object accepts.

Errors with CodecError::InvalidField when payload_length is not exactly payload.len(). The declared length is written ahead of the payload, so a mismatch is a frame Self::read_object cannot parse and one no caller could fix by appending bytes.

Trait Implementations

impl Clone for SubgroupObjectReader

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SubgroupObjectReader

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

Formats the value using the given formatter.