From c5153ca095ae07d07986f3d71cc831ece049d71c Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Thu, 1 Nov 2018 10:22:21 +0100
Subject: [PATCH] - fixed: Do not pass Sysex messages to Windows's GS Wavetable
 synth.

This will totally refuse to play a MIDI if that happens.
Duke Nukem's Alienz.mid, which did not play before works after this change.
---
 src/sound/i_musicinterns.h                     | 1 +
 src/sound/mididevices/music_win_mididevice.cpp | 6 ++++++
 src/sound/midisources/midisource.h             | 3 +++
 src/sound/midisources/midisource_hmi.cpp       | 2 +-
 src/sound/midisources/midisource_smf.cpp       | 2 +-
 src/sound/midisources/midisource_xmi.cpp       | 2 +-
 src/sound/musicformats/music_midistream.cpp    | 1 +
 7 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/sound/i_musicinterns.h b/src/sound/i_musicinterns.h
index c638afbe7..b3cebfccf 100644
--- a/src/sound/i_musicinterns.h
+++ b/src/sound/i_musicinterns.h
@@ -82,6 +82,7 @@ public:
 	virtual bool Preprocess(MIDIStreamer *song, bool looping);
 	virtual FString GetStats();
 	virtual int GetDeviceType() const { return MDEV_DEFAULT; }
+	virtual bool CanHandleSysex() const { return true; }
 };
 
 
diff --git a/src/sound/mididevices/music_win_mididevice.cpp b/src/sound/mididevices/music_win_mididevice.cpp
index 2e1a4c5a9..f9820033f 100644
--- a/src/sound/mididevices/music_win_mididevice.cpp
+++ b/src/sound/mididevices/music_win_mididevice.cpp
@@ -86,6 +86,12 @@ public:
 	bool Update() override;
 	void PrecacheInstruments(const uint16_t *instruments, int count);
 	DWORD PlayerLoop();
+	bool CanHandleSysex() const override
+	{
+		// No Sysex for GS synth.
+		return VolumeWorks;
+	}
+
 
 //protected:
 	static void CALLBACK CallbackFunc(HMIDIOUT, UINT, DWORD_PTR, DWORD, DWORD);
diff --git a/src/sound/midisources/midisource.h b/src/sound/midisources/midisource.h
index 7e7381eae..12e0188b4 100644
--- a/src/sound/midisources/midisource.h
+++ b/src/sound/midisources/midisource.h
@@ -25,6 +25,7 @@ class MIDISource
 protected:
 
 	bool isLooping = false;
+	bool skipSysex = false;
 	int Division = 0;
 	int Tempo = 500000;
 	int InitialTempo = 500000;
@@ -54,6 +55,8 @@ public:
 		LoopLimit = looplimit;
 		isLooping = looped;
 	}
+
+	void SkipSysex() { skipSysex = true; }
 	
 	bool isValid() const { return Division > 0; }
 	int getDivision() const { return Division; }
diff --git a/src/sound/midisources/midisource_hmi.cpp b/src/sound/midisources/midisource_hmi.cpp
index 0c555268c..1fe08e9cc 100644
--- a/src/sound/midisources/midisource_hmi.cpp
+++ b/src/sound/midisources/midisource_hmi.cpp
@@ -644,7 +644,7 @@ uint32_t *HMISong::SendCommand (uint32_t *events, TrackInfo *track, uint32_t del
 		if (event == MIDI_SYSEX || event == MIDI_SYSEXEND)
 		{
 			len = ReadVarLen(track);
-			if (len >= (MAX_MIDI_EVENTS-1)*3*4)
+			if (len >= (MAX_MIDI_EVENTS-1)*3*4 || skipSysex)
 			{ // This message will never fit. Throw it away.
 				track->TrackP += len;
 			}
diff --git a/src/sound/midisources/midisource_smf.cpp b/src/sound/midisources/midisource_smf.cpp
index d7e8808f1..42299b7f8 100644
--- a/src/sound/midisources/midisource_smf.cpp
+++ b/src/sound/midisources/midisource_smf.cpp
@@ -585,7 +585,7 @@ uint32_t *MIDISong2::SendCommand (uint32_t *events, TrackInfo *track, uint32_t d
 		if (event == MIDI_SYSEX || event == MIDI_SYSEXEND)
 		{
 			len = track->ReadVarLen();
-			if (len >= (MAX_MIDI_EVENTS-1)*3*4)
+			if (len >= (MAX_MIDI_EVENTS-1)*3*4 || skipSysex)
 			{ // This message will never fit. Throw it away.
 				track->TrackP += len;
 			}
diff --git a/src/sound/midisources/midisource_xmi.cpp b/src/sound/midisources/midisource_xmi.cpp
index caad0897c..3e2fcac87 100644
--- a/src/sound/midisources/midisource_xmi.cpp
+++ b/src/sound/midisources/midisource_xmi.cpp
@@ -515,7 +515,7 @@ uint32_t *XMISong::SendCommand (uint32_t *events, EventSource due, uint32_t dela
 		if (event == MIDI_SYSEX || event == MIDI_SYSEXEND)
 		{
 			len = track->ReadVarLen();
-			if (len >= (MAX_MIDI_EVENTS-1)*3*4)
+			if (len >= (MAX_MIDI_EVENTS-1)*3*4 || skipSysex)
 			{ // This message will never fit. Throw it away.
 				track->EventP += len;
 			}
diff --git a/src/sound/musicformats/music_midistream.cpp b/src/sound/musicformats/music_midistream.cpp
index 85c4135de..60061b264 100644
--- a/src/sound/musicformats/music_midistream.cpp
+++ b/src/sound/musicformats/music_midistream.cpp
@@ -364,6 +364,7 @@ bool MIDIStreamer::InitPlayback()
 	}
 
 	source->CheckCaps(MIDI->GetTechnology());
+	if (!MIDI->CanHandleSysex()) source->SkipSysex();
 
 	if (MIDI->Preprocess(this, m_Looping))
 	{