decoder/Bridge: add flag to make initial seek errors fatal

NEWS

@@ -7,6 +7,8 @@ ver 0.21.24 (not yet released)
   - modplug: fix Windows build failure
   - wildmidi: attempt to detect WildMidi using pkg-config
   - wildmidi: fix Windows build failure
+* player
+  - don't restart current song if seeking beyond end
 * Android
   - enable the decoder plugins ModPlug and WildMidi
   - fix build failure with Android NDK r21

src/decoder/Bridge.cxx

@@ -33,6 +33,8 @@
 #include "util/ConstBuffer.hxx"
 #include "util/StringBuffer.hxx"
 
+#include <stdexcept>
+
 #include <assert.h>
 #include <string.h>
 #include <math.h>
@@ -344,6 +346,10 @@ DecoderBridge::SeekError()
 		/* d'oh, we can't seek to the sub-song start position,
 		   what now? - no idea, ignoring the problem for now. */
 		initial_seek_running = false;
+
+		if (initial_seek_essential)
+			error = std::make_exception_ptr(std::runtime_error("Decoder failed to seek"));
+
 		return;
 	}
 

src/decoder/Bridge.hxx

@@ -63,6 +63,11 @@ public:
 	bool initial_seek_pending;
 
 	/**
+	 * Are initial seek failures fatal?
+	 */
+	const bool initial_seek_essential;
+
+	/**
 	 * Is the initial seek currently running?  During this time,
 	 * the decoder command is SEEK.  This flag is set by
 	 * decoder_get_virtual_command(), when the virtual SEEK
@@ -107,9 +112,11 @@ public:
 	std::exception_ptr error;
 
 	DecoderBridge(DecoderControl &_dc, bool _initial_seek_pending,
+		      bool _initial_seek_essential,
 		      std::unique_ptr<Tag> _tag)
 		:dc(_dc),
 		 initial_seek_pending(_initial_seek_pending),
+		 initial_seek_essential(_initial_seek_essential),
 		 song_tag(std::move(_tag)) {}
 
 	~DecoderBridge();

src/decoder/Control.cxx

@@ -90,6 +90,7 @@ DecoderControl::IsCurrentSong(const DetachedSong &_song) const noexcept
 void
 DecoderControl::Start(std::unique_ptr<DetachedSong> _song,
 		      SongTime _start_time, SongTime _end_time,
+		      bool _initial_seek_essential,
 		      MusicBuffer &_buffer,
 		      std::shared_ptr<MusicPipe> _pipe) noexcept
 {
@@ -99,6 +100,7 @@ DecoderControl::Start(std::unique_ptr<DetachedSong> _song,
 	song = std::move(_song);
 	start_time = _start_time;
 	end_time = _end_time;
+	initial_seek_essential = _initial_seek_essential;
 	buffer = &_buffer;
 	pipe = std::move(_pipe);
 

src/decoder/Control.hxx

@@ -117,6 +117,12 @@ public:
 
 	bool seek_error;
 	bool seekable;
+
+	/**
+	 * @see #DecoderBridge::initial_seek_essential
+	 */
+	bool initial_seek_essential;
+
 	SongTime seek_time;
 
 private:
@@ -398,11 +404,14 @@ public:
 	 * owned and freed by the decoder
 	 * @param start_time see #DecoderControl
 	 * @param end_time see #DecoderControl
+	 * @param initial_seek_essential see
+	 * #DecoderBridge::initial_seek_essential
 	 * @param pipe the pipe which receives the decoded chunks (owned by
 	 * the caller)
 	 */
 	void Start(std::unique_ptr<DetachedSong> song,
 		   SongTime start_time, SongTime end_time,
+		   bool initial_seek_essential,
 		   MusicBuffer &buffer,
 		   std::shared_ptr<MusicPipe> pipe) noexcept;
 

src/decoder/Thread.cxx

@@ -461,6 +461,7 @@ decoder_run_song(DecoderControl &dc,
 		dc.start_time = dc.seek_time;
 
 	DecoderBridge bridge(dc, dc.start_time.IsPositive(),
+			     dc.initial_seek_essential,
 			     /* pass the song tag only if it's
 				authoritative, i.e. if it's a local
 				file - tags on "stream" songs are just

src/player/Thread.cxx

@@ -223,7 +223,8 @@ private:
 	 *
 	 * Caller must lock the mutex.
 	 */
-	void StartDecoder(std::shared_ptr<MusicPipe> pipe) noexcept;
+	void StartDecoder(std::shared_ptr<MusicPipe> pipe,
+			  bool initial_seek_essential) noexcept;
 
 	/**
 	 * The decoder has acknowledged the "START" command (see
@@ -364,7 +365,8 @@ public:
 };
 
 void
-Player::StartDecoder(std::shared_ptr<MusicPipe> _pipe) noexcept
+Player::StartDecoder(std::shared_ptr<MusicPipe> _pipe,
+		     bool initial_seek_essential) noexcept
 {
 	assert(queued || pc.command == PlayerCommand::SEEK);
 	assert(pc.next_song != nullptr);
@@ -376,6 +378,7 @@ Player::StartDecoder(std::shared_ptr<MusicPipe> _pipe) noexcept
 
 	dc.Start(std::make_unique<DetachedSong>(*pc.next_song),
 		 start_time, pc.next_song->GetEndTime(),
+		 initial_seek_essential,
 		 buffer, std::move(_pipe));
 }
 
@@ -633,7 +636,7 @@ Player::SeekDecoder() noexcept
 		pipe->Clear();
 
 		/* re-start the decoder */
-		StartDecoder(pipe);
+		StartDecoder(pipe, true);
 		ActivateDecoder();
 
 		pc.seeking = true;
@@ -711,7 +714,7 @@ Player::ProcessCommand() noexcept
 		pc.CommandFinished();
 
 		if (dc.IsIdle())
-			StartDecoder(std::make_shared<MusicPipe>());
+			StartDecoder(std::make_shared<MusicPipe>(), false);
 
 		break;
 
@@ -982,7 +985,7 @@ Player::Run() noexcept
 
 	const std::lock_guard<Mutex> lock(pc.mutex);
 
-	StartDecoder(pipe);
+	StartDecoder(pipe, true);
 	ActivateDecoder();
 
 	pc.state = PlayerState::PLAY;
@@ -1022,7 +1025,7 @@ Player::Run() noexcept
 
 			assert(dc.pipe == nullptr || dc.pipe == pipe);
 
-			StartDecoder(std::make_shared<MusicPipe>());
+			StartDecoder(std::make_shared<MusicPipe>(), false);
 		}
 
 		if (/* no cross-fading if MPD is going to pause at the