Fix SDRplay init/stop leaks and stats endpoint

cmd/sdrd/main.go

@@ -389,11 +389,7 @@ func main() {
 
 	http.HandleFunc("/api/stats", func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("Content-Type", "application/json")
-		if sp, ok := src.(sdr.StatsProvider); ok {
-			_ = json.NewEncoder(w).Encode(sp.Stats())
-			return
-		}
-		_ = json.NewEncoder(w).Encode(sdr.SourceStats{})
+		_ = json.NewEncoder(w).Encode(srcMgr.Stats())
 	})
 
 	http.HandleFunc("/api/gpu", func(w http.ResponseWriter, r *http.Request) {

internal/sdrplay/sdrplay.go

@@ -112,7 +112,12 @@ func New(sampleRate int, centerHz float64, gainDb float64, bwKHz int) (sdr.Sourc
 	s.cond = sync.NewCond(&s.mu)
 	s.resizeBuffer(sampleRate, 0)
 	s.handle = cgo.NewHandle(s)
-	return s, s.configure(sampleRate, centerHz, gainDb, bwKHz)
+	if err := s.configure(sampleRate, centerHz, gainDb, bwKHz); err != nil {
+		s.handle.Delete()
+		s.handle = 0
+		return nil, err
+	}
+	return s, nil
 }
 
 func (s *Source) configure(sampleRate int, centerHz float64, gainDb float64, bwKHz int) error {