altoslib: create logfiles preference object. check link in existing_data

[fw/altos] / altoslib / AltosTelemetryReader.java

diff --git a/altoslib/AltosTelemetryReader.java b/altoslib/AltosTelemetryReader.java
index 8803e19f74087b528fdc0281877d03bb85a00ec9..7539452d4ad9cf3cb609a48b58292b197e128911 100644 (file)
--- a/altoslib/AltosTelemetryReader.java
+++ b/altoslib/AltosTelemetryReader.java
@@ -185,6 +185,9 @@ public class AltosTelemetryReader extends AltosFlightReader {
        }
 
        private static AltosFlightReader existing_data(AltosLink link) {
+               if (link == null)
+                       return null;
+
                File    file = AltosPreferences.logfile(link.serial);
                if (file != null) {
                        AltosStateIterable      iterable = AltosStateIterable.iterable(file);