Running several one-shot commands at once returned "no results" for queries that
had plenty. Four defects, each of which made a dead session look like an empty
network:
- The peer listener bound its port inside a detached thread and panicked on
EADDRINUSE, unwinding that thread alone. The process carried on with no
listener, so no peer could deliver a search response. `Listen::bind` now takes
the socket before login and falls back to an ephemeral port when the
configured one is held.
- SetWaitPort advertised the configured port whether or not it was bound, so
peers dialled a sibling process that discarded responses to tickets it never
issued. The port the listener really holds is what gets advertised, mapped
through UPnP, and reported by `whoami` and `serve`.
- A zero-byte read is EOF on a TCP socket, but MessageReader reported it as
success, so a server that closed cleanly left the actor polling a dead socket.
It is now an error, and Relogged (code 41) has a handler. The peer actor
classifies that error: a control connection that was established and then
closed is a clean disconnect, because peers drop idle sockets while the bytes
move over their own connection, and reporting an error there fails every
download queued with that peer including the one streaming. A connection that
never established keeps the error path, which is what the server-brokered
fallback reads to know a peer is unreachable.
- A session the server cut off - usually because another process logged in under
the same name - exited 4, documented as "it worked and found nothing". Callers
concluded the file was unavailable. Sessions now record why they ended and
those verdicts become exit 7.
The server allows one session per account, so concurrency still needs a distinct
--username per run; SKILL.md documents that. The listener port needs no such
care any more.
Six e2e tests against soulfind cover it, each of which fails without the fix: a
taken listen port, a displaced session, three clients searching at once under
one configured port, the two CLI equivalents, and a peer that hangs up its
control connection while a transfer is still to come.
BREAKING CHANGE: `Listen::start` is replaced by `Listen::bind` and
`Listen::serve`, so the caller owns the socket and can read the port it actually
bound. `Client::listen_port` and `Client::session_loss` are new.
Michel de Graaf
e8a48c6b06