Use rwlock to protect the bufConn map

Map in golang do not support concurrent read and write, use
rwlock to protect it.

console/console.go

@@ -33,7 +33,7 @@ type Console struct {
 	session   plugins.ConsoleSession // interface for plugin
 	running   chan bool
 	node      *Node
-	mutex     *sync.Mutex
+	mutex     *sync.RWMutex
 }
 
 func NewConsole(baseSession *plugins.BaseSession, node *Node) *Console {
@@ -44,13 +44,15 @@ func NewConsole(baseSession *plugins.BaseSession, node *Node) *Console {
 		network:   new(common.Network),
 		bufConn:   make(map[net.Conn]chan []byte),
 		running:   make(chan bool, 0),
-		mutex:     new(sync.Mutex)}
+		mutex:     new(sync.RWMutex)}
 }
 
 // Accept connection from client
 func (c *Console) Accept(conn net.Conn) {
 	plog.DebugNode(c.node.StorageNode.Name, "Accept connection from client")
+	c.mutex.Lock()
 	c.bufConn[conn] = make(chan []byte)
+	c.mutex.Unlock()
 	go c.writeTarget(conn)
 	go c.writeClient(conn)
 }
@@ -79,10 +81,13 @@ func (c *Console) writeTarget(conn net.Conn) {
 		c.Disconnect(conn)
 	}()
 	for {
+		c.mutex.RLock()
 		if _, ok := c.bufConn[conn]; !ok {
+			c.mutex.RUnlock()
 			plog.ErrorNode(c.node.StorageNode.Name, fmt.Sprintf("Failed to find the connection from bufConn, the connection may be closed."))
 			return
 		}
+		c.mutex.RUnlock()
 		n, err := c.network.ReceiveInt(conn)
 		if err != nil {
 			plog.WarningNode(c.node.StorageNode.Name, fmt.Sprintf("Failed to receive message head from client. Error:%s.", err.Error()))
@@ -132,10 +137,13 @@ func (c *Console) writeClient(conn net.Conn) {
 		plog.WarningNode(c.node.StorageNode.Name, fmt.Sprintf("Failed to log message to %s. Error:%s", logFile, err.Error()))
 	}
 	for {
+		c.mutex.RLock()
 		if bufChan, ok = c.bufConn[conn]; !ok {
+			c.mutex.RUnlock()
 			plog.ErrorNode(c.node.StorageNode.Name, fmt.Sprintf("Failed to find the connection from bufConn, the connection may be closed."))
 			return
 		}
+		c.mutex.RUnlock()
 		b := <-bufChan
 		err = c.network.SendByteWithLengthTimeout(conn, b, clientTimeout)
 		if err != nil {
@@ -192,9 +200,11 @@ func (c *Console) readTarget() {
 func (c *Console) writeClientChan(buf []byte) {
 	b := make([]byte, len(buf))
 	copy(b, buf)
+	c.mutex.RLock()
 	for _, v := range c.bufConn {
 		v <- b
 	}
+	c.mutex.RUnlock()
 }
 
 func (c *Console) Start() {
@@ -217,25 +227,25 @@ func (c *Console) Stop() {
 func (c *Console) ListSessionUser() []string {
 	ret := make([]string, len(c.bufConn))
 	i := 0
+	c.mutex.RLock()
 	for c, _ := range c.bufConn {
 		ret[i] = c.RemoteAddr().String()
 		i++
 	}
+	c.mutex.RUnlock()
 	return ret
 }
 
 // close session from rest api
 func (c *Console) Close() {
 	plog.DebugNode(c.node.StorageNode.Name, "Close console session.")
+	c.mutex.Lock()
 	for k, v := range c.bufConn {
-		c.mutex.Lock()
-		if _, ok := c.bufConn[k]; ok {
-			close(v)
-		}
+		close(v)
 		k.Close()
 		delete(c.bufConn, k)
-		c.mutex.Unlock()
 	}
+	c.mutex.Unlock()
 	if c.running != nil {
 		c.mutex.Lock()
 		if c.running != nil {