Struct StreamAckRanges 

pub struct StreamAckRanges {
    pub stream_id: u64,
    pub ack_seq: u64,
    pub ranges: Vec<(u64, u64)>,
}

Receiver → sender positive SACK-range ACK (STREAM_ACK_BATCHING R-1).

Semantics, precisely: ack_seq cumulatively acknowledges every sequence < ack_seq (identical to StreamWindow::ack_seq — the receiver’s next_expected). ranges selectively acknowledge received runs strictly above ack_seq as half-open [start, end) intervals. ack_seq itself is by definition the missing head — it is never inside a range, and the cumulative run is never duplicated as a range. Example: ack_seq = 101, ranges = [(102, 10001)] ⇒ everything below 101 received, 101 missing, 102..=10000 received.

Wire order is DESCENDING by end (newest first): when the receiver truncates to MAX_ACK_RANGES it drops the oldest ranges — the ones the next cumulative advance covers first. Ranges are fully merged: non-overlapping and non-adjacent.

The sender feeds this to ReliableStream::on_ack_ranges, which removes SACKed packets from the retransmit window so one lost head packet no longer RTO-floods everything behind it.

Fields

stream_id: u64

Stream the ack applies to.

ack_seq: u64

Cumulative ack — every sequence < ack_seq is received.

ranges: Vec<(u64, u64)>

Received runs strictly above ack_seq: half-open [start, end), descending by end, merged, 1..=MAX_ACK_RANGES entries.

Implementations

impl StreamAckRanges

pub const MIN_SIZE: usize

Minimum wire size: header + one range. A rangeless message is meaningless (the grant’s ack_seq already covers the contiguous case) and is rejected by Self::decode.

pub const MAX_SIZE: usize

Maximum wire size (header + MAX_ACK_RANGES ranges).

pub fn encode(&self) -> Vec<u8>

Encode to 16 + 16·n bytes.

pub fn decode(data: &[u8]) -> Result<Self, StreamWindowCodecError>

Decode with strict validation. Rejects: truncated / non-16·n bodies, zero or more than MAX_ACK_RANGES ranges, empty or inverted ranges, ranges not strictly above ack_seq, and any ordering that is not strictly-descending / merged (overlap or adjacency means the producer failed to merge — treat as malformed rather than guessing).

Trait Implementations

impl Clone for StreamAckRanges

fn clone(&self) -> StreamAckRanges

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StreamAckRanges

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

Formats the value using the given formatter.

impl Eq for StreamAckRanges

impl PartialEq for StreamAckRanges

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for StreamAckRanges