From bcab29d53a8981993444c5d5fda642bc82ccd73f Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Tue, 5 Nov 2024 13:16:28 +0100
Subject: [PATCH] filter/Filter: Flush() returns empty span, not nullptr

---
 src/filter/Filter.hxx | 2 +-
 src/output/Thread.cxx | 2 +-
 test/run_filter.cxx   | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/filter/Filter.hxx b/src/filter/Filter.hxx
index b533965d4..ed82a2a19 100644
--- a/src/filter/Filter.hxx
+++ b/src/filter/Filter.hxx
@@ -49,7 +49,7 @@ public:
 
 	/**
 	 * Flush pending data and return it.  This should be called
-	 * repeatedly until it returns nullptr.
+	 * repeatedly until it returns an empty span.
 	 *
 	 * After calling this method, this object cannot be used again
          * (not even Reset() is allowed).
diff --git a/src/output/Thread.cxx b/src/output/Thread.cxx
index e1c3ed477..fd6ee3ef3 100644
--- a/src/output/Thread.cxx
+++ b/src/output/Thread.cxx
@@ -389,7 +389,7 @@ AudioOutputControl::InternalDrain() noexcept
 
 		while (true) {
 			auto buffer = source.Flush();
-			if (buffer.data() == nullptr)
+			if (buffer.empty())
 				break;
 
 			PlayFull(*output, buffer);
diff --git a/test/run_filter.cxx b/test/run_filter.cxx
index eab1dd692..2c318b7c4 100644
--- a/test/run_filter.cxx
+++ b/test/run_filter.cxx
@@ -128,7 +128,7 @@ try {
 
 	while (true) {
 		auto dest = filter->Flush();
-		if (dest.data() == nullptr)
+		if (dest.empty())
 			break;
 		output_fd.FullWrite(dest);
 	}