The channel server had several concurrency issues found by the race
detector during isolation testing:
- acceptClients could send on a closed acceptConns channel during
shutdown, causing a panic. Replace close(acceptConns) with a done
channel and select-based shutdown signaling in both acceptClients
and manageSessions.
- invalidateSessions read isShuttingDown and iterated sessions without
holding the lock. Rewrite with ticker + done channel select and
snapshot sessions under lock before processing timeouts.
- sendLoop/recvLoop accessed global _config.ErupeConfig.LoopDelay
which races with tests modifying the global. Use the per-server
erupeConfig instead.
- logoutPlayer panicked on DB errors and crashed on nil DB (no-db
test scenarios). Guard with nil check and log errors instead.
- Shutdown was not idempotent, double-calling caused double-close
panic on done channel.
Add 5 channel isolation tests verifying independent shutdown,
listener failure, session panic recovery, cross-channel registry
after shutdown, and stage isolation.
