Fix #19: server-lifecycle & state-lock hardening#25
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- SessionEnd teardown is now bounded: teardownServerSession takes a lock-acquire
timeout and returns {skipped, reason:"lock-timeout", diagnostic} on
contention; the SessionEnd hook passes a 3s server-lock + 500ms state-lock
budget, logs the diagnostic, and skips clearing state on timeout so it can't be
killed mid-teardown by the hook host. ensureServer also fails safely when a
bounded acquisition times out.
- State lock adds async APIs (withStateLockAsync / updateStateAsync) that yield
the event loop via awaitable polling instead of Atomics.wait. The async
companion paths (enqueue/spawn bookkeeping, terminal-index sync, cancel read,
in-flight cancellation) and the SessionEnd job cleanup now use them. The
synchronous lock keeps stale-takeover recovery (no premature default timeout;
lockAcquireTimeoutMs is opt-in).
- EPERM is treated as "unconfirmed" (not alive) for lease liveness, so a reused
foreign pid can no longer hold server teardown hostage for the 6h TTL; the TTL
still covers legitimate long sessions.
- server.json is written atomically (temp-file + rename), reusing the state
writer.
npm test: 79 passed, 0 failed, 0 skipped (localhost tests included).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
…sue-19-lifecycle # Conflicts: # tests/runtime.test.mjs
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Closes #19.
Server-lifecycle & state-lock robustness.
teardownServerSessionpreviously acquired the server lock with no acquisition timeout, so under contention it could exceed the ~5s SessionEnd hook budget and be killed mid-teardown. It now accepts a lock-acquire timeout and returns{skipped, reason:"lock-timeout", diagnostic}on contention; the hook passes a 3s server-lock + 500ms state-lock budget, logs the diagnostic, and skipsclearServerSessionon timeout.ensureServeralso fails safely when a bounded acquisition times out (found via an internal review pass).withStateLockAsync/updateStateAsyncthat poll with awaitablesleepinstead ofAtomics.wait, and migrated the async paths (SessionEnd job cleanup; enqueue/spawn bookkeeping, terminal-index sync, cancel read, in-flight cancellation in the companion) to them, so contention no longer freezes concurrent async work. The synchronous lock keeps its stale-takeover recovery —lockAcquireTimeoutMsis opt-in, with no premature default.processIsAlivenow reports EPERM as "unconfirmed" andisLeaseActiverequires a confirmed-alive owner, so a reused foreign pid can't hold teardown hostage for the 6h TTL. Plugin processes are same-user, so legitimate leases are unaffected.server.json(Low).saveServerSessionnow uses the atomic temp-file + rename writer.Verification:
npm test— 79 passed, 0 failed, 0 skipped (localhost tests included). Regression tests cover bounded teardown diagnostics, sync stale-lock recovery beyond the former deadline, async-lock event-loop yielding, EPERM lease expiry, and atomicserver.json.🤖 Generated with Claude Code