Fix Application shutdown (#120)

Previously we used the `red::Main` function, which was changing the hash
every few updates, so we changed the offset to `WinMain` in
45d49e0.

`WinMain` as a `quick_exit` function, which prevents our hook from
catching the return value, and by extension not calling `App::Shutdown`
at all.

Author: wopss

src/dll/App.cpp

@@ -11,8 +11,9 @@
 #include "Hooks/ExecuteProcess.hpp"
 #include "Hooks/InitScripts.hpp"
 #include "Hooks/LoadScripts.hpp"
-#include "Hooks/Main_Hooks.hpp"
+#include "Hooks/QuickExit.hpp"
 #include "Hooks/ValidateScripts.hpp"
+#include "Hooks/WinMain.hpp"
 #include "Hooks/gsmState_SessionActive.hpp"
 
 namespace
@@ -124,9 +125,10 @@ void App::Destruct()
     DetourTransaction transaction;
     if (transaction.IsValid())
     {
-        auto success = Hooks::CGameApplication::Detach() && Hooks::Main::Detach() && Hooks::ExecuteProcess::Detach() &&
-                       Hooks::InitScripts::Detach() && Hooks::LoadScripts::Detach() &&
-                       Hooks::ValidateScripts::Detach() && Hooks::AssertionFailed::Detach() &&
+        auto success = Hooks::WinMain::Detach() && Hooks::QuickExit::Detach() && Hooks::CGameApplication::Detach() &&
+                       Hooks::ExecuteProcess::Detach() && Hooks::InitScripts::Detach() &&
+                       Hooks::LoadScripts::Detach() && Hooks::ValidateScripts::Detach() &&
+                       Hooks::AssertionFailed::Detach() && Hooks::CollectSaveableSystems::Detach() &&
                        Hooks::gsmState_SessionActive::Detach();
         if (success)
         {
@@ -222,10 +224,10 @@ bool App::AttachHooks() const
         return false;
     }
 
-    auto success = Hooks::Main::Attach() && Hooks::CGameApplication::Attach() && Hooks::ExecuteProcess::Attach() &&
-                   Hooks::InitScripts::Attach() && Hooks::LoadScripts::Attach() && Hooks::ValidateScripts::Attach() &&
-                   Hooks::AssertionFailed::Attach() && Hooks::CollectSaveableSystems::Attach() &&
-                   Hooks::gsmState_SessionActive::Attach();
+    auto success = Hooks::WinMain::Attach() && Hooks::QuickExit::Attach() && Hooks::CGameApplication::Attach() &&
+                   Hooks::ExecuteProcess::Attach() && Hooks::InitScripts::Attach() && Hooks::LoadScripts::Attach() &&
+                   Hooks::ValidateScripts::Attach() && Hooks::AssertionFailed::Attach() &&
+                   Hooks::CollectSaveableSystems::Attach() && Hooks::gsmState_SessionActive::Attach();
     if (success)
     {
         return transaction.Commit();

src/dll/Detail/AddressHashes.hpp

@@ -3,6 +3,9 @@
 
 namespace Hashes
 {
+constexpr std::uint32_t WinMain = 240386859ul;
+constexpr std::uint32_t QuickExit = 388826167ul;
+
 constexpr std::uint32_t AssertionFailed = 4285205681UL;
 
 constexpr std::uint32_t CBaseEngine_InitScripts = 2875532677UL;
@@ -15,6 +18,5 @@ constexpr std::uint32_t Global_ExecuteProcess = 2203918127UL;
 constexpr std::uint32_t GsmState_SessionActive_ReportErrorCode = 2141394294UL;
 
 constexpr std::uint32_t IGameSystem_vtbl = 1854670959UL;
-constexpr std::uint32_t Main = 240386859UL;
 constexpr std::uint32_t ScriptValidator_Validate = 898639042UL;
 } // namespace Hashes

src/dll/Hooks/Main_Hooks.cpp

@@ -0,0 +1,78 @@
+#include "QuickExit.hpp"
+#include "App.hpp"
+#include "Detail/AddressHashes.hpp"
+#include "Hook.hpp"
+
+#include <cstdint>
+
+namespace
+{
+bool isAttached = false;
+
+int WINAPI _QuickExit_fnc(std::int32_t aExitCode);
+Hook<decltype(&_QuickExit_fnc)> _QuickExit(Hashes::QuickExit, &_QuickExit_fnc);
+
+int WINAPI _QuickExit_fnc(std::int32_t aExitCode)
+{
+    try
+    {
+        auto app = App::Get();
+        if (app)
+        {
+            app->Shutdown();
+        }
+    }
+    catch (const std::exception& e)
+    {
+        SHOW_MESSAGE_BOX_AND_EXIT_FILE_LINE("An exception occurred while RED4ext was shutting down.\n\n{}",
+                                            Utils::Widen(e.what()));
+    }
+    catch (...)
+    {
+        SHOW_MESSAGE_BOX_AND_EXIT_FILE_LINE("An unknown exception occurred while RED4ext was shutting down.");
+    }
+
+    return _QuickExit(aExitCode);
+}
+} // namespace
+
+bool Hooks::QuickExit::Attach()
+{
+    spdlog::trace("Trying to attach the hook for the 'quick_exit' function at {:#x}...", _QuickExit.GetAddress());
+
+    auto result = _QuickExit.Attach();
+    if (result != NO_ERROR)
+    {
+        spdlog::error("Could not attach the hook for the 'quick_exit' function. Detour error code: {}", result);
+    }
+    else
+    {
+        spdlog::trace("The hook for the 'quick_exit' function was attached");
+    }
+
+    isAttached = result == NO_ERROR;
+    return isAttached;
+}
+
+bool Hooks::QuickExit::Detach()
+{
+    if (!isAttached)
+    {
+        return false;
+    }
+
+    spdlog::trace("Trying to detach the hook for the 'quick_exit' function at {:#x}...", _QuickExit.GetAddress());
+
+    auto result = _QuickExit.Detach();
+    if (result != NO_ERROR)
+    {
+        spdlog::error("Could not detach the hook for the 'quick_exit' function. Detour error code: {}", result);
+    }
+    else
+    {
+        spdlog::trace("The hook for the 'quick_exit' function was detached");
+    }
+
+    isAttached = result != NO_ERROR;
+    return !isAttached;
+}

src/dll/Hooks/Main_Hooks.hpp

@@ -0,0 +1,7 @@
+#pragma once
+
+namespace Hooks::QuickExit
+{
+bool Attach();
+bool Detach();
+} // namespace Hooks::QuickExit

src/dll/Hooks/QuickExit.cpp

@@ -0,0 +1,74 @@
+#include "WinMain.hpp"
+#include "Addresses.hpp"
+#include "App.hpp"
+#include "Detail/AddressHashes.hpp"
+#include "Hook.hpp"
+
+namespace
+{
+bool isAttached = false;
+
+int WINAPI WinMain_fnc(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow);
+Hook<decltype(&WinMain_fnc)> _WinMain(Hashes::WinMain, &WinMain_fnc);
+
+int WINAPI WinMain_fnc(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)
+{
+    try
+    {
+        auto app = App::Get();
+        app->Startup();
+    }
+    catch (const std::exception& e)
+    {
+        SHOW_MESSAGE_BOX_AND_EXIT_FILE_LINE("An exception occurred while RED4ext was starting up.\n\n{}",
+                                            Utils::Widen(e.what()));
+    }
+    catch (...)
+    {
+        SHOW_MESSAGE_BOX_AND_EXIT_FILE_LINE("An unknown exception occurred while RED4ext was starting up.");
+    }
+
+    return _WinMain(hInstance, hPrevInstance, pCmdLine, nCmdShow);
+}
+} // namespace
+
+bool Hooks::WinMain::Attach()
+{
+    spdlog::trace("Trying to attach the hook for the WinMain function at {:#x}...", _WinMain.GetAddress());
+
+    auto result = _WinMain.Attach();
+    if (result != NO_ERROR)
+    {
+        spdlog::error("Could not attach the hook for the WinMain function. Detour error code: {}", result);
+    }
+    else
+    {
+        spdlog::trace("The hook for the WinMain function was attached");
+    }
+
+    isAttached = result == NO_ERROR;
+    return isAttached;
+}
+
+bool Hooks::WinMain::Detach()
+{
+    if (!isAttached)
+    {
+        return false;
+    }
+
+    spdlog::trace("Trying to detach the hook for the WinMain function at {:#x}...", _WinMain.GetAddress());
+
+    auto result = _WinMain.Detach();
+    if (result != NO_ERROR)
+    {
+        spdlog::error("Could not detach the hook for the WinMain function. Detour error code: {}", result);
+    }
+    else
+    {
+        spdlog::trace("The hook for the WinMain function was detached");
+    }
+
+    isAttached = result != NO_ERROR;
+    return !isAttached;
+}

src/dll/Hooks/QuickExit.hpp

@@ -0,0 +1,7 @@
+#pragma once
+
+namespace Hooks::WinMain
+{
+bool Attach();
+bool Detach();
+} // namespace Hooks::WinMain