From b1fe1059040cd8fd2cbd8ad7b163c3b30d481902 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@musicpd.org>
Date: Wed, 7 Nov 2018 00:17:48 +0100
Subject: [PATCH] output/Source: reset current_chunk in Open()

If the output is already open, the `current_chunk` pointer may be
bogus and out of sync with `SharedPipeConsumer::chunk`, leading to an
assertion failure in `SharedPipeConsumer::Consume()`.

Fixes #411
---
 NEWS                  | 2 ++
 src/output/Source.cxx | 4 +++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/NEWS b/NEWS
index f44fa5f23..f244ae53b 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,8 @@ ver 0.21.2 (not yet released)
 * decoder
   - ffmpeg: require FFmpeg 3.1 or later
   - ffmpeg: fix broken sound with certain codecs
+* output
+  - httpd: fix crash with "always_on"
 
 ver 0.21.1 (2018/11/04)
 * protocol
diff --git a/src/output/Source.cxx b/src/output/Source.cxx
index e516d05bc..7c47ad40c 100644
--- a/src/output/Source.cxx
+++ b/src/output/Source.cxx
@@ -41,8 +41,10 @@ AudioOutputSource::Open(const AudioFormat audio_format, const MusicPipe &_pipe,
 {
 	assert(audio_format.IsValid());
 
-	if (!IsOpen() || &_pipe != &pipe.GetPipe())
+	if (!IsOpen() || &_pipe != &pipe.GetPipe()) {
+		current_chunk = nullptr;
 		pipe.Init(_pipe);
+	}
 
 	/* (re)open the filter */