Method onSend

src/streams.ts:199–212

(size: number)

  // Called when a write of `size` bytes is about to be sent. Returns a token that must be
  // passed to onAck() when the ack arrives, and whether the sender should block (window full).
  onSend(size: number): { token: SendToken, shouldBlock: boolean } {
    this.bytesInFlight += size;

    let token: SendToken = {
      sentTime: this.now(),
      size,
      deliveredAtSend: this.delivered,
      deliveredTimeAtSend: this.deliveredTime,
      windowAtSend: this.window,
      windowFullAtSend: this.bytesInFlight >= this.window,
    };

    return { token, shouldBlock: token.windowFullAtSend };
  }

  // Called when a previously-sent write fails. Restores bytesInFlight without updating
  // any BDP estimates.