From d7dc9acf2f8de78f058904c5390e6fc646ec9aad Mon Sep 17 00:00:00 2001
From: OV2 <OV2@sessionclan.de>
Date: Mon, 14 Feb 2022 01:05:57 +0100
Subject: [PATCH] win32: stop trying to send audio data after device removal

---
 win32/CWaveOut.cpp | 17 +++++++++++++----
 win32/CWaveOut.h   |  2 ++
 win32/CXAudio2.cpp |  3 +++
 win32/CXAudio2.h   | 19 ++++++++++++++++++-
 4 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/win32/CWaveOut.cpp b/win32/CWaveOut.cpp
index 7ba04949..df1071e0 100644
--- a/win32/CWaveOut.cpp
+++ b/win32/CWaveOut.cpp
@@ -20,17 +20,25 @@ CWaveOut::~CWaveOut(void)
     DeInitSoundOutput();
 }
 
-void CALLBACK WaveCallback(HWAVEOUT hWave, UINT uMsg, DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2)
+void CALLBACK CWaveOut::WaveCallback(HWAVEOUT hWave, UINT uMsg, DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2)
 {
+	CWaveOut *wo = (CWaveOut*)dwUser;
     if (uMsg == WOM_DONE)
     {
-        InterlockedDecrement(((volatile LONG *)dwUser));
+        InterlockedDecrement(&wo->bufferCount);
         SetEvent(GUI.SoundSyncEvent);
     }
+	else if (uMsg == WOM_CLOSE) // also sent on device removals
+	{
+		// this stops any output from being sent to the non existing device
+		wo->initDone = false;
+	}
 }
 
 bool CWaveOut::SetupSound()
 {
+	DeInitSoundOutput();
+
     WAVEFORMATEX wfx;
     wfx.wFormatTag = WAVE_FORMAT_PCM;
     wfx.nChannels = 2;
@@ -43,7 +51,7 @@ bool CWaveOut::SetupSound()
 	// subtract -1, we added "Default" as first index - Default will yield -1, which is WAVE_MAPPER
 	int device_index = FindDeviceIndex(GUI.AudioDevice) - 1;
 
-    waveOutOpen(&hWaveOut, device_index, &wfx, (DWORD_PTR)WaveCallback, (DWORD_PTR)&bufferCount, CALLBACK_FUNCTION);
+    waveOutOpen(&hWaveOut, device_index, &wfx, (DWORD_PTR)WaveCallback, (DWORD_PTR)this, CALLBACK_FUNCTION);
 
     UINT32 blockTime = GUI.SoundBufferSize / blockCount;
     singleBufferSamples = (Settings.SoundPlaybackRate * blockTime) / 1000;
@@ -91,7 +99,7 @@ bool CWaveOut::InitSoundOutput()
 
 void CWaveOut::DeInitSoundOutput()
 {
-    if (!initDone)
+    if (!hWaveOut)
         return;
 
     StopPlayback();
@@ -109,6 +117,7 @@ void CWaveOut::DeInitSoundOutput()
     waveHeaders.clear();
 
     waveOutClose(hWaveOut);
+	hWaveOut = NULL;
 
     initDone = false;
 }
diff --git a/win32/CWaveOut.h b/win32/CWaveOut.h
index 833283bd..01fb7e3e 100644
--- a/win32/CWaveOut.h
+++ b/win32/CWaveOut.h
@@ -44,4 +44,6 @@ class CWaveOut : public IS9xSoundOutput
     void SetVolume(double volume);
 	std::vector<std::wstring> GetDeviceList();
 	int FindDeviceIndex(TCHAR *audio_device);
+
+	static void CALLBACK WaveCallback(HWAVEOUT hWave, UINT uMsg, DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2);
 };
diff --git a/win32/CXAudio2.cpp b/win32/CXAudio2.cpp
index 4323e5d2..c4302a36 100644
--- a/win32/CXAudio2.cpp
+++ b/win32/CXAudio2.cpp
@@ -108,6 +108,8 @@ bool CXAudio2::InitXAudio2(void)
 	if(initDone)
 		return true;
 
+	DeInitXAudio2();
+
 	HRESULT hr;
 	if ( FAILED(hr = XAudio2Create( &pXAudio2, 0 , XAUDIO2_DEFAULT_PROCESSOR ) ) ) {
 		DXTRACE_ERR_MSGBOX(TEXT("Unable to create XAudio2 object."),hr);
@@ -115,6 +117,7 @@ bool CXAudio2::InitXAudio2(void)
 		return false;
 	}
 	initDone = true;
+	pXAudio2->RegisterForCallbacks(this);
 	return true;
 }
 
diff --git a/win32/CXAudio2.h b/win32/CXAudio2.h
index ea520796..10c9f8eb 100644
--- a/win32/CXAudio2.h
+++ b/win32/CXAudio2.h
@@ -11,7 +11,7 @@
 #include <windows.h>
 #include "IS9xSoundOutput.h"
 
-class CXAudio2 : public IXAudio2VoiceCallback, public IS9xSoundOutput
+class CXAudio2 : public IXAudio2VoiceCallback, public IXAudio2EngineCallback, public IS9xSoundOutput
 {
 private:
 	IXAudio2SourceVoice *pSourceVoice;
@@ -56,6 +56,23 @@ public:
 	STDMETHODIMP_(void) OnVoiceProcessingPassStart(UINT32 BytesRequired) {}
 
 
+	// inherited from IXAudio2EngineCallback - we only use OnCriticalError
+
+	// Called by XAudio2 just before an audio processing pass begins.
+	STDMETHODIMP_(void) OnProcessingPassStart() {}
+
+	// Called just after an audio processing pass ends.
+	STDMETHODIMP_(void) OnProcessingPassEnd() {}
+
+	// Called in the event of a critical system error which requires XAudio2
+	// to be closed down and restarted.  The error code is given in Error.
+	STDMETHODIMP_(void) OnCriticalError(HRESULT Error)
+	{
+		// this stops any output from being sent to the non existing device
+		initDone = false;
+	}
+
+
 	// Inherited from IS9xSoundOutput
 	bool InitSoundOutput(void) { return InitXAudio2(); }
 	void DeInitSoundOutput(void) { DeInitXAudio2(); }