From c30c293d6f9acd6c89d075c8004a6a4b60078af3 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Sat, 28 Jan 2023 07:41:47 +0100
Subject: [PATCH] input/async: check for errors in Seek()

Fixes a busy loop in BufferingInputStream::RunThreadLocked() because
the method never learns that seeking is ignored, even though the HTTP
stream is already broken and can never be read; nobody cared to check
for errors.

Closes https://github.com/MusicPlayerDaemon/MPD/issues/1727
---
 NEWS                           |  1 +
 src/input/AsyncInputStream.cxx | 12 ++++++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/NEWS b/NEWS
index 788f93d53..1d21a4b98 100644
--- a/NEWS
+++ b/NEWS
@@ -12,6 +12,7 @@ ver 0.24 (not yet released)
   - add option to disable archive plugins in mpd.conf
 * input
   - curl: add "connect_timeout" configuration
+  - curl: fix busy loop after connection failed
 * decoder
   - hybrid_dsd: remove
   - opus: implement bitrate calculation
diff --git a/src/input/AsyncInputStream.cxx b/src/input/AsyncInputStream.cxx
index 9133dada4..2a117b4d6 100644
--- a/src/input/AsyncInputStream.cxx
+++ b/src/input/AsyncInputStream.cxx
@@ -102,9 +102,17 @@ AsyncInputStream::Seek(std::unique_lock<Mutex> &lock,
 	assert(IsReady());
 	assert(seek_state == SeekState::NONE);
 
-	if (new_offset == offset)
-		/* no-op */
+	if (new_offset == offset) {
+		/* no-op, but if the stream is not open anymore (maybe
+		   because it has failed), nothing can be read, so we
+		   should check for errors here instead of pretending
+		   everything's fine */
+
+		if (!open)
+			Check();
+
 		return;
+	}
 
 	if (!IsSeekable())
 		throw std::runtime_error("Not seekable");