Fix concurrent map writes in presence queue

xmpp/component.go

@@ -90,7 +90,9 @@ func heartbeat(component *xmpp.Component) {
 			if err != nil {
 				gateway.LogBadPresence(presence)
 			} else {
+				gateway.QueueLock.Lock()
 				delete(gateway.Queue, key)
+				gateway.QueueLock.Unlock()
 			}
 		}
 

xmpp/gateway/gateway.go

@@ -3,6 +3,7 @@ package gateway
 import (
 	"encoding/xml"
 	"strings"
+	"sync"
 
 	"dev.narayana.im/narayana/telegabber/xmpp/extensions"
 
@@ -14,6 +15,7 @@ import (
 
 // Queue stores presences to send later
 var Queue = make(map[string]*stanza.Presence)
+var QueueLock = sync.Mutex{}
 
 // Jid stores the component's JID object
 var Jid *stanza.Jid
@@ -178,7 +180,9 @@ func SendPresence(component *xmpp.Component, to string, args ...args.V) error {
 			return err
 		}
 	} else {
+		QueueLock.Lock()
 		Queue[presence.From+presence.To] = &presence
+		QueueLock.Unlock()
 	}
 
 	return nil