From bfd093d22b1a39af711e302a9c4c0cf95fcb75c9 Mon Sep 17 00:00:00 2001
From: Kawe Mazidjatari <48657826+Mauler125@users.noreply.github.com>
Date: Sun, 2 Jul 2023 11:28:07 +0200
Subject: [PATCH] Fix rare crash in 'ImGui_ImplWin32_WndProcHandler'

Don't run the 'ImGui_ImplWin32_WndProcHandler' if we are shutting down. During rare occasions when closing the game while hovering over the game window, 'ImGui_ImplWin32_WndProcHandler' is getting called while parts or all of the ImGui systems have been shut down, leading to a crash. The fix is to check if the engine is restarting or shutting down before running the ImGui window procedure logic.
---
 r5dev/engine/sys_mainwind.cpp | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/r5dev/engine/sys_mainwind.cpp b/r5dev/engine/sys_mainwind.cpp
index 493930ba..bca3375e 100644
--- a/r5dev/engine/sys_mainwind.cpp
+++ b/r5dev/engine/sys_mainwind.cpp
@@ -8,6 +8,7 @@
 #include "windows/id3dx.h"
 #include "windows/input.h"
 #include "engine/sys_mainwind.h"
+#include "engine/sys_engine.h"
 #include "gameui/IConsole.h"
 #include "gameui/IBrowser.h"
 
@@ -30,17 +31,25 @@ int CGame::WindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 	if (!g_bImGuiInitialized)
 		return v_CGame__WindowProc(hWnd, uMsg, wParam, lParam);
 
+	const IEngine::EngineState_t state = g_pEngine->GetState();
+
+	if (state == IEngine::DLL_CLOSE ||
+		state == IEngine::DLL_RESTART)
+		return v_CGame__WindowProc(hWnd, uMsg, wParam, lParam);
+
 	ImGui_ImplWin32_WndProcHandler(hWnd, uMsg, wParam, lParam);
 
 	if (uMsg == WM_KEYDOWN || uMsg == WM_SYSKEYDOWN)
 	{
-		if (wParam == g_pImGuiConfig->m_ConsoleConfig.m_nBind0 || wParam == g_pImGuiConfig->m_ConsoleConfig.m_nBind1)
+		if (wParam == g_pImGuiConfig->m_ConsoleConfig.m_nBind0 ||
+			wParam == g_pImGuiConfig->m_ConsoleConfig.m_nBind1)
 		{
 			g_pConsole->m_bActivate ^= true;
 			ResetInput(); // Disable input to game when console is drawn.
 		}
 
-		if (wParam == g_pImGuiConfig->m_BrowserConfig.m_nBind0 || wParam == g_pImGuiConfig->m_BrowserConfig.m_nBind1)
+		if (wParam == g_pImGuiConfig->m_BrowserConfig.m_nBind0 ||
+			wParam == g_pImGuiConfig->m_BrowserConfig.m_nBind1)
 		{
 			g_pBrowser->m_bActivate ^= true;
 			ResetInput(); // Disable input to game when browser is drawn.