Store pending messages in list.

This avoids copying elements around as they are added to the back and fetched from the front.

src/app/spreed-speakfreely-server/connection.go

@@ -59,7 +59,7 @@ type Connection struct {
 
 	// Data handling.
 	condition *sync.Cond
-	queue     []Buffer
+	queue     list.List
 	mutex     sync.Mutex
 	isClosed  bool
 
@@ -82,7 +82,6 @@ func NewConnection(h *Hub, ws *websocket.Conn, remoteAddr string) *Connection {
 		RemoteAddr: remoteAddr,
 	}
 	c.condition = sync.NewCond(&c.mutex)
-	c.queue = make([]Buffer, 0)
 
 	return c
 
@@ -95,7 +94,15 @@ func (c *Connection) close() {
 		c.mutex.Lock()
 		c.User = nil
 		c.isClosed = true
-		c.queue = c.queue[:0]
+		for {
+			head := c.queue.Front()
+			if head == nil {
+				break
+			}
+			c.queue.Remove(head)
+			message := head.Value.(Buffer)
+			message.Decref()
+		}
 		c.condition.Signal()
 		c.mutex.Unlock()
 	}
@@ -206,12 +213,12 @@ func (c *Connection) send(message Buffer) {
 		return
 	}
 	//fmt.Println("Outbound queue size", c.Idx, len(c.queue))
-	if len(c.queue) >= maxQueueSize {
+	if c.queue.Len() >= maxQueueSize {
-		log.Println("Outbound queue overflow", c.Idx, len(c.queue))
+		log.Println("Outbound queue overflow", c.Idx, c.queue.Len())
 		return
 	}
 	message.Incref()
-	c.queue = append(c.queue, message)
+	c.queue.PushBack(message)
 	c.condition.Signal()
 
 }
@@ -240,7 +247,7 @@ func (c *Connection) writePump() {
 
 		c.mutex.Lock()
 		// Wait until something todo.
-		for !ping && !c.isClosed && len(c.queue) == 0 {
+		for !ping && !c.isClosed && c.queue.Len() == 0 {
 			// Wait on signal (this also unlocks while waiting, and locks again when got the signal).
 			c.condition.Wait()
 		}
@@ -250,9 +257,13 @@ func (c *Connection) writePump() {
 			goto cleanup
 		}
 		// Flush queue if something.
-		for len(c.queue) > 0 {
+		for {
-			message := c.queue[0]
+			head := c.queue.Front()
-			c.queue = c.queue[1:]
+			if head == nil {
+				break
+			}
+			c.queue.Remove(head)
+			message := head.Value.(Buffer)
 			if ping {
 				// Send ping.
 				ping = false