use better demo locking to prevent double parsing

csgo/demo_loader.go

@@ -240,10 +240,17 @@ func (dml *DemoMatchLoader) Setup(config *DemoMatchLoaderConfig) error {
 }
 
 func (dml *DemoMatchLoader) LoadDemo(demo *Demo) error {
+	if dml.IsLoading(demo) {
+		log.Infof("[DL] Skipping %s: parsing in progress", demo.ShareCode)
+		return nil
+	}
+	dml.lockDemo(demo)
+
 	select {
 	case dml.parseDemo <- demo:
 		return nil
 	default:
+		dml.unlockDemo(demo)
 		return fmt.Errorf("queue full")
 	}
 }
@@ -368,11 +375,6 @@ func (dml *DemoMatchLoader) demoWorker() {
 }
 
 func (dml *DemoMatchLoader) handleDemo(demo *Demo, apiKey string, rl *rate.Limiter) error {
-	if dml.IsLoading(demo) {
-		log.Infof("[DL] Skipping %s: parsing in progress", demo.ShareCode)
-		return nil
-	}
-	dml.lockDemo(demo)
 	defer dml.unlockDemo(demo)
 
 	if !dml.GCReady {