Measured first: tools/java-oracle's ModemRun joins two networks by a pair
of Java modems over TCP on localhost. The modem has no card and adds no
delay of its own — a frame takes the cables on both sides, nothing more.
The core pairs the two enabled modems on a port (Swift's inProject, with
its conditions and cycle suppression) on Java's timing: no 20 ms. The
modem example of FILIUS now pings through instead of failing the core.
A modem of another project (relay) gives its frames to whoever runs the
engine and puts on its cable what comes back, with this engine's frame
and packet numbers; a frame dies after MAXIMUM_RELAY_HOPS trips.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
TcpRun loses exactly one frame (loseFirst: the card's output buffer drops
it; the sender's packet log still shows it, as with setDrop) in three new
stories: lostSynAck, lostFin, lostLastFin.
Measured: Java never repeats a SYN+ACK or a FIN. The server gives a
handshake up after one timeout (3 RTT) and closes with a FIN from SYN_RCVD
(its boundary check sometimes lets it wait twice; it means once). After its
FIN a socket waits at most five times, each wait ended by a segment or the
timeout; then it is gone. The core does the same (TCP_CLOSING_WAITS, with
TIME_WAIT in the loop) and shows CLOSED where Java leaves the state
standing (a named Java bug).
One departure: a repeated SYN in SYN_RCVD gets the SYN+ACK once more and
the wait starts anew; Java closes there, but its client never repeats the
SYN. lostSynAck is compared up to the second SYN (JAVA_UNTIL); the rest is
an engine test.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A send hands its frame to the card and returns, as in Java; the frames
travel while the clock advances. Swift's send ran the network until every
frame had arrived; the option swiftSends keeps that for the Swift
comparison. Waiting calls (TCP connect, acknowledgement) now run event by
event until the answer instead of to the timeout.
UDP and TCP send through a thread per node and protocol (Java's
TransportProtokoll): one segment after the other; while IP waits for ARP,
the next send blocks and a segment from an event queues behind it. Senders
that wait take their turns in the order they came (a fair lock; Java's
leaves the order to chance).
All four ArpRun stories now match Java FILIUS, including when each call
returns. Tests let frames arrive explicitly with letFramesArrive.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
First slice of the TypeScript port of the filius-ipad runtime engine,
with 29 tests ported from the Swift suite. Parts not ported yet throw
NotPortedError instead of guessing.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
julian.kiedaischandClaude Opus 5.5