From 1a43f5145d511f37870639fee256c76eb5cb40d3 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@musicpd.org>
Date: Wed, 14 Nov 2018 10:08:29 +0100
Subject: [PATCH] output/alsa: throw on snd_pcm_writei() error while draining

This implements real error handling, and avoids calling
CancelInternal() from this code path.
---
 src/output/plugins/AlsaOutputPlugin.cxx | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/output/plugins/AlsaOutputPlugin.cxx b/src/output/plugins/AlsaOutputPlugin.cxx
index 8932a02fb..8b505db7d 100644
--- a/src/output/plugins/AlsaOutputPlugin.cxx
+++ b/src/output/plugins/AlsaOutputPlugin.cxx
@@ -727,9 +727,12 @@ AlsaOutput::DrainInternal()
 	/* drain period_buffer */
 	if (!period_buffer.IsEmpty()) {
 		auto frames_written = WriteFromPeriodBuffer();
-		if (frames_written < 0 && frames_written != -EAGAIN) {
-			CancelInternal();
-			return true;
+		if (frames_written < 0) {
+			if (frames_written == -EAGAIN)
+				return false;
+
+			throw FormatRuntimeError("snd_pcm_writei() failed: %s",
+						 snd_strerror(-frames_written));
 		}
 
 		if (!period_buffer.IsEmpty())