From b6308bab4f92376034360a15dfa4c756e9cafe26 Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <stenzek@gmail.com>
Date: Tue, 24 May 2022 00:20:29 +1000
Subject: [PATCH] Qt: Initialize COM ourselves on EmuThread

If we don't, SDL initializes it first in STA mode, which prevents MT
mode from being used, which prevents us from using XAudio2.
---
 pcsx2-qt/EmuThread.cpp |  4 +++-
 pcsx2-qt/QtHost.cpp    |  6 ++----
 pcsx2/VMManager.cpp    | 23 +++++++++++++++++++++++
 pcsx2/VMManager.h      |  3 +++
 4 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/pcsx2-qt/EmuThread.cpp b/pcsx2-qt/EmuThread.cpp
index 1bcf3e0537..6ffe480ec1 100644
--- a/pcsx2-qt/EmuThread.cpp
+++ b/pcsx2-qt/EmuThread.cpp
@@ -228,7 +228,8 @@ void EmuThread::run()
 	m_event_loop = new QEventLoop();
 	m_started_semaphore.release();
 
-	if (!VMManager::Internal::InitializeMemory())
+	// neither of these should ever fail.
+	if (!VMManager::Internal::InitializeGlobals() || !VMManager::Internal::InitializeMemory())
 		pxFailRel("Failed to allocate memory map");
 
 	// we need input sources ready for binding
@@ -252,6 +253,7 @@ void EmuThread::run()
 	InputManager::CloseSources();
 	VMManager::WaitForSaveStateFlush();
 	VMManager::Internal::ReleaseMemory();
+	VMManager::Internal::ReleaseGlobals();
 	PerformanceMetrics::SetCPUThread(Threading::ThreadHandle());
 	moveToThread(m_ui_thread);
 	deleteLater();
diff --git a/pcsx2-qt/QtHost.cpp b/pcsx2-qt/QtHost.cpp
index d579a62070..c411cff839 100644
--- a/pcsx2-qt/QtHost.cpp
+++ b/pcsx2-qt/QtHost.cpp
@@ -86,13 +86,11 @@ bool QtHost::Initialize()
 
 	if (!InitializeConfig())
 	{
-		Console.WriteLn("Failed to initialize config.");
+		// NOTE: No point translating this, because no config means the language won't be loaded anyway.
+		QMessageBox::critical(nullptr, QStringLiteral("Error"), QStringLiteral("Failed to initialize config."));
 		return false;
 	}
 
-	if (!VMManager::Internal::InitializeGlobals())
-		return false;
-
 	HookSignals();
 	return true;
 }
diff --git a/pcsx2/VMManager.cpp b/pcsx2/VMManager.cpp
index 82dd1fdf02..3b6e39b279 100644
--- a/pcsx2/VMManager.cpp
+++ b/pcsx2/VMManager.cpp
@@ -62,6 +62,10 @@
 #include "common/emitter/x86_intrin.h"
 #endif
 
+#ifdef _WIN32
+#include "common/RedtapeWindows.h"
+#endif
+
 namespace VMManager
 {
 	static void LoadSettings();
@@ -187,6 +191,18 @@ std::string VMManager::GetGameName()
 
 bool VMManager::Internal::InitializeGlobals()
 {
+	// On Win32, we have a bunch of things which use COM (e.g. SDL, XAudio2, etc).
+	// We need to initialize COM first, before anything else does, because otherwise they might
+	// initialize it in single-threaded/apartment mode, which can't be changed to multithreaded.
+#ifdef _WIN32
+	HRESULT hr = CoInitializeEx(nullptr, COINIT_MULTITHREADED);
+	if (FAILED(hr))
+	{
+		Host::ReportErrorAsync("Error", fmt::format("CoInitializeEx() failed: {:08X}", hr));
+		return false;
+	}
+#endif
+
 	x86caps.Identify();
 	x86caps.CountCores();
 	x86caps.SIMD_EstablishMXCSRmask();
@@ -196,6 +212,13 @@ bool VMManager::Internal::InitializeGlobals()
 	return true;
 }
 
+void VMManager::Internal::ReleaseGlobals()
+{
+#ifdef _WIN32
+	CoUninitialize();
+#endif
+}
+
 bool VMManager::Internal::InitializeMemory()
 {
 	pxAssert(!s_vm_memory && !s_cpu_provider_pack);
diff --git a/pcsx2/VMManager.h b/pcsx2/VMManager.h
index df29926d54..227d980389 100644
--- a/pcsx2/VMManager.h
+++ b/pcsx2/VMManager.h
@@ -153,6 +153,9 @@ namespace VMManager
 		/// Performs early global initialization.
 		bool InitializeGlobals();
 
+		/// Releases resources allocated in InitializeGlobals().
+		void ReleaseGlobals();
+
 		/// Reserves memory for the virtual machines.
 		bool InitializeMemory();