From eac6836898140a3755160261a7afbc5907d4fe5d Mon Sep 17 00:00:00 2001
From: "Andrew D. Zonenberg" <azonenberg@drawersteak.com>
Date: Tue, 7 Nov 2023 00:09:06 -0800
Subject: [PATCH] Session: don't crash on empty filters file

---
 src/ngscopeclient/Session.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/ngscopeclient/Session.cpp b/src/ngscopeclient/Session.cpp
index d1390651f..46d80a63b 100644
--- a/src/ngscopeclient/Session.cpp
+++ b/src/ngscopeclient/Session.cpp
@@ -295,8 +295,11 @@ bool Session::LoadWaveformData(int version, const string& dataDir)
 		fclose(fp);
 
 		auto docs = YAML::LoadAllFromFile(fname);
-		if(!LoadWaveformDataForFilters(version, docs[0], dataDir))
-			return false;
+		if(docs.size())
+		{
+			if(!LoadWaveformDataForFilters(version, docs[0], dataDir))
+				return false;
+		}
 	}
 
 	//Load data for each scope
@@ -333,6 +336,8 @@ bool Session::LoadWaveformDataForFilters(
 		const YAML::Node& node,
 		const string& dataDir)
 {
+	if(!node)
+		return true;
 	auto waveforms = node["waveforms"];
 	if(!waveforms)
 		return true;