From 7d1ed2577ed4de7b9a71e6bf0f01737b4cbbaece Mon Sep 17 00:00:00 2001
From: F0ur <xuzhijie@xindong.com>
Date: Sat, 22 Aug 2020 23:06:53 +0800
Subject: [PATCH] fix(ws):  fix eventConn panic when ws connect close

---
 server/websocket.go | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/server/websocket.go b/server/websocket.go
index ce961439..784e1c20 100644
--- a/server/websocket.go
+++ b/server/websocket.go
@@ -324,18 +324,21 @@ func (c *websocketConn) handleRequest(bot *coolq.CQBot, payload []byte) {
 func (s *websocketServer) onBotPushEvent(m coolq.MSG) {
 	s.eventConnMutex.Lock()
 	defer s.eventConnMutex.Unlock()
-	pos := 0
-	for _, conn := range s.eventConn {
+	for i, l := 0, len(s.eventConn); i<l; i++ {
+		conn := s.eventConn[i]
 		log.Debugf("向WS客户端 %v 推送Event: %v", conn.RemoteAddr().String(), m.ToJson())
-		err := conn.WriteMessage(websocket.TextMessage, []byte(m.ToJson()))
-		if err != nil {
+		if err := conn.WriteMessage(websocket.TextMessage, []byte(m.ToJson())); err != nil {
 			_ = conn.Close()
-			s.eventConn = append(s.eventConn[:pos], s.eventConn[pos+1:]...)
-			if pos > 0 {
-				pos++
+			next := i +1
+			if next >= l {
+				next = l -1
 			}
+			s.eventConn[i], s.eventConn[next] = s.eventConn[next], s.eventConn[i]
+			s.eventConn = append(s.eventConn[:next], s.eventConn[next+1:]...)
+			i--
+			l--
+			conn = nil
 		}
-		pos++
 	}
 }