Check for there being any servers to connect to

resolves #197

client.go

@@ -196,10 +196,18 @@ func (c *client) Connect() Token {
 		c.persist.Open()
 
 		c.setConnected(connecting)
+		c.errors = make(chan error, 1)
+		c.stop = make(chan struct{})
+
 		var rc byte
 		cm := newConnectMsgFromOptions(&c.options)
 		protocolVersion := c.options.ProtocolVersion
 
+		if len(c.options.Servers) == 0 {
+			t.setError(fmt.Errorf("No servers defined to connect to"))
+			return
+		}
+
 		for _, broker := range c.options.Servers {
 			c.options.ProtocolVersion = protocolVersion
 		CONN:
@@ -247,23 +255,19 @@ func (c *client) Connect() Token {
 
 		if c.conn == nil {
 			ERROR.Println(CLI, "Failed to connect to a broker")
+			c.setConnected(disconnected)
+			c.persist.Close()
 			t.returnCode = rc
 			if rc != packets.ErrNetworkError {
-				t.err = packets.ConnErrors[rc]
+				t.setError(packets.ConnErrors[rc])
 			} else {
-				t.err = fmt.Errorf("%s : %s", packets.ConnErrors[rc], err)
+				t.setError(fmt.Errorf("%s : %s", packets.ConnErrors[rc], err))
 			}
-			c.setConnected(disconnected)
-			c.persist.Close()
-			t.flowComplete()
 			return
 		}
 
 		c.options.protocolVersionExplicit = true
 
-		c.errors = make(chan error, 1)
-		c.stop = make(chan struct{})
-
 		if c.options.KeepAlive != 0 {
 			atomic.StoreInt32(&c.pingOutstanding, 0)
 			atomic.StoreInt64(&c.lastReceived, time.Now().Unix())

token.go

@@ -93,8 +93,6 @@ func (b *baseToken) Error() error {
 }
 
 func (b *baseToken) setError(e error) {
-	b.m.Lock()
-	defer b.m.Unlock()
 	b.err = e
 	b.flowComplete()
 }