From e807ed58704c29c3f894c7fb65442afdde4679b3 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Fri, 8 Jul 2022 18:11:00 +0200
Subject: [PATCH] output/PipeWire: ignore SPA_PROP_channelVolumes if
 n_values==0

After connecting, PipeWire sometimes sends SPA_PROP_channelVolumes
with no values, and this led to "volume=-NaN".
---
 src/output/plugins/PipeWireOutputPlugin.cxx | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/output/plugins/PipeWireOutputPlugin.cxx b/src/output/plugins/PipeWireOutputPlugin.cxx
index cfa45292d..a64471a15 100644
--- a/src/output/plugins/PipeWireOutputPlugin.cxx
+++ b/src/output/plugins/PipeWireOutputPlugin.cxx
@@ -223,6 +223,9 @@ private:
 	}
 
 	void OnChannelVolumes(const struct pw_stream_control &control) noexcept {
+		if (control.n_values < 1)
+			return;
+
 		float sum = std::accumulate(control.values,
 					    control.values + control.n_values,
 					    0.0f);