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Zoltán Papp
210de91665
AddCloseListener deduplicated listeners by comparing reflect.ValueOf(callback).Pointer(). For a method value that pointer is the address of the compiler-generated wrapper, not an identity bound to the receiver, so every peer's w.onRelayClientDisconnected compared equal. All peers on the home relay register under the same connectionURL key, so only the first registration survived and the rest were silently dropped. On a relay disconnect those peers were never notified: statusRelay stayed connected and the reconnect guard never fired. The relayed net.Conn itself was closed by closeAllConns, so nothing leaked, but the peer state machine did not learn about it. Foreign relays had the same defect scoped to the peers sharing that server. Rather than fixing the deduplication, drop the peer-level listener registry entirely. A relayed Conn now exposes Context(), cancelled when the connection is torn down, with a cancellation cause naming the reason. This is the same shape quic-go uses for its Conn and Stream types, and it removes the whole class of problems around listener identity, lifetime and deregistration: the signal belongs to the resource instead of a side table. WorkerRelay watches that context in a goroutine whose lifetime matches the connection. A watcher that wakes up for a superseded connection compares the conn pointer against the current one and returns without touching the state machine, so a fast relay reconnect cannot have a stale watcher tear down the connection that replaced it. Client.SetOnDisconnectListener stays: it is server-level and drives the reconnect guard and foreign relay eviction, unrelated to peers. handleRelayReady also checks the conn context, closing the race where the relay dies between OpenConn and the readiness handoff and the peer would otherwise build a WireGuard endpoint over a dead connection. TestNotifierDoubleAdd covered the removed mechanism and is gone. TestForeignAutoClose asserted nothing (both branches logged); it now waits for the relay to leave the client map and fails if it does not.