persist last seen on shutdown

irc/client.go

 
 func (client *Client) writeLoop() {
 	for {
-		client.performWrite()
+		client.performWrite(0)
 		client.writerSemaphore.Release()
 
 		client.stateMutex.RLock()
 	}
 }
 
-func (client *Client) performWrite() {
+func (client *Client) performWrite(additionalDirtyBits uint) {
 	client.stateMutex.Lock()
-	dirtyBits := client.dirtyBits
+	dirtyBits := client.dirtyBits | additionalDirtyBits
 	client.dirtyBits = 0
 	account := client.account
 	client.stateMutex.Unlock()
 		client.server.accounts.saveModes(account, uModes)
 	}
 }
+
+// Blocking store; see Channel.Store and Socket.BlockingWrite
+func (client *Client) Store(dirtyBits uint) (err error) {
+	defer func() {
+		client.stateMutex.Lock()
+		isDirty := client.dirtyBits != 0
+		client.stateMutex.Unlock()
+
+		if isDirty {
+			client.wakeWriter()
+		}
+	}()
+
+	client.writerSemaphore.Acquire()
+	defer client.writerSemaphore.Release()
+	client.performWrite(dirtyBits)
+	return nil
+}

irc/server.go

 	//TODO(dan): Make sure we disallow new nicks
 	for _, client := range server.clients.AllClients() {
 		client.Notice("Server is shutting down")
+		if client.AlwaysOn() {
+			client.Store(IncludeLastSeen)
+		}
 	}
 
 	if err := server.store.Close(); err != nil {