From 148d7287e846afbe1bd32bf83c0083f39ec01cac Mon Sep 17 00:00:00 2001
From: narzoul <narzoul@users.noreply.github.com>
Date: Fri, 2 Apr 2021 18:04:00 +0200
Subject: [PATCH] Fixed incompatibility with Steam overlay

See issue #68.
---
 DDrawCompat/Common/CompatQueryInterface.h | 20 +++++------------
 DDrawCompat/Common/CompatVtable.h         |  5 +++++
 DDrawCompat/Common/Hook.cpp               | 27 ++++++++++++++---------
 DDrawCompat/D3dDdi/KernelModeThunks.cpp   |  2 +-
 4 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/DDrawCompat/Common/CompatQueryInterface.h b/DDrawCompat/Common/CompatQueryInterface.h
index 759c172..24a3548 100644
--- a/DDrawCompat/Common/CompatQueryInterface.h
+++ b/DDrawCompat/Common/CompatQueryInterface.h
@@ -20,6 +20,9 @@ namespace Compat
 	{
 	};
 
+	template <typename SrcIntf> struct IsConvertible<SrcIntf, IUnknown> : std::true_type {};
+	template <typename DestIntf> struct IsConvertible<IUnknown, DestIntf> : std::true_type {};
+
 	template<> struct IsConvertible<IDirect3D, IDirect3D7> : std::false_type {};
 	template<> struct IsConvertible<IDirect3D2, IDirect3D7> : std::false_type {};
 	template<> struct IsConvertible<IDirect3D3, IDirect3D7> : std::false_type {};
@@ -61,6 +64,8 @@ namespace Compat
 #define DEFINE_INTF_ID(Intf) \
 	template<> inline const IID& getIntfId<Intf>() { return IID_##Intf; }
 
+	DEFINE_INTF_ID(IUnknown);
+
 	DEFINE_INTF_ID(IDirectDraw);
 	DEFINE_INTF_ID(IDirectDraw2);
 	DEFINE_INTF_ID(IDirectDraw4);
@@ -94,21 +99,6 @@ namespace Compat
 
 #undef DEFINE_INTF_ID
 
-	template <typename NewIntf>
-	void queryInterface(IUnknown& origIntf, NewIntf*& newIntf)
-	{
-		getOrigVtable(newIntf).QueryInterface(
-			reinterpret_cast<NewIntf*>(&origIntf),
-			getIntfId<NewIntf>(),
-			reinterpret_cast<void**>(&newIntf));
-	}
-
-	template <typename OrigIntf>
-	void queryInterface(OrigIntf& origIntf, IUnknown*& newIntf)
-	{
-		getOrigVtable(&origIntf).QueryInterface(&origIntf, IID_IUnknown, reinterpret_cast<void**>(&newIntf));
-	}
-
 	template <typename NewIntf, typename OrigIntf>
 	std::enable_if_t<IsConvertible<OrigIntf, NewIntf>::value>
 	queryInterface(OrigIntf& origIntf, NewIntf*& newIntf)
diff --git a/DDrawCompat/Common/CompatVtable.h b/DDrawCompat/Common/CompatVtable.h
index abcfdd7..9f6d9f6 100644
--- a/DDrawCompat/Common/CompatVtable.h
+++ b/DDrawCompat/Common/CompatVtable.h
@@ -15,6 +15,11 @@ const Vtable<Interface>& getOrigVtable(Interface* /*This*/)
 	return CompatVtable<Vtable<Interface>>::s_origVtable;
 }
 
+inline const IUnknownVtbl& getOrigVtable(IUnknown* This)
+{
+	return *This->lpVtbl;
+}
+
 template <typename Vtable>
 class CompatVtable
 {
diff --git a/DDrawCompat/Common/Hook.cpp b/DDrawCompat/Common/Hook.cpp
index 4be47ba..5c614a0 100644
--- a/DDrawCompat/Common/Hook.cpp
+++ b/DDrawCompat/Common/Hook.cpp
@@ -1,6 +1,5 @@
 #undef CINTERFACE
 
-#include <filesystem>
 #include <list>
 #include <sstream>
 #include <string>
@@ -23,7 +22,7 @@ namespace
 	bool g_isDbgEngInitialized = false;
 
 	PIMAGE_NT_HEADERS getImageNtHeaders(HMODULE module);
-	std::filesystem::path getModulePath(HMODULE module);
+	std::string getModulePath(HMODULE module);
 	bool initDbgEng();
 
 	FARPROC* findProcAddressInIat(HMODULE module, const char* procName)
@@ -107,7 +106,7 @@ namespace
 		return static_cast<unsigned>(endOffset - g_debugBase);
 	}
 
-	std::filesystem::path getModulePath(HMODULE module)
+	std::string getModulePath(HMODULE module)
 	{
 		char path[MAX_PATH] = {};
 		GetModuleFileName(module, path, sizeof(path));
@@ -120,7 +119,7 @@ namespace
 
 		std::ostringstream oss;
 #ifdef DEBUGLOGS
-		oss << Compat::funcPtrToStr(targetFunc);
+		oss << Compat::funcPtrToStr(targetFunc) << ' ';
 
 		char origFuncPtrStr[20] = {};
 		if (!funcName)
@@ -128,20 +127,26 @@ namespace
 			sprintf_s(origFuncPtrStr, "%p", origFuncPtr);
 			funcName = origFuncPtrStr;
 		}
+
+		auto prevTargetFunc = targetFunc;
 #endif
 
 		while (true)
 		{
+			unsigned instructionSize = 0;
 			if (0xE9 == targetFunc[0])
 			{
-				targetFunc += 1 + *reinterpret_cast<int*>(targetFunc + 1);
+				instructionSize = 5;
+				targetFunc += instructionSize + *reinterpret_cast<int*>(targetFunc + 1);
 			}
 			else if (0xEB == targetFunc[0])
 			{
-				targetFunc += 1 + static_cast<signed char>(targetFunc[1]);
+				instructionSize = 2;
+				targetFunc += instructionSize + *reinterpret_cast<signed char*>(targetFunc + 1);
 			}
 			else if (0xFF == targetFunc[0] && 0x25 == targetFunc[1])
 			{
+				instructionSize = 6;
 				targetFunc = **reinterpret_cast<BYTE***>(targetFunc + 2);
 			}
 			else
@@ -149,12 +154,11 @@ namespace
 				break;
 			}
 #ifdef DEBUGLOGS
-			oss << " -> " << Compat::funcPtrToStr(targetFunc);
+			oss << Compat::hexDump(prevTargetFunc, instructionSize) << " -> " << Compat::funcPtrToStr(targetFunc) << ' ';
+			prevTargetFunc = targetFunc;
 #endif
 		}
 
-		LOG_DEBUG << "Hooking function: " << funcName << " (" << oss.str() << ')';
-
 		if (Compat::getModuleHandleFromAddress(targetFunc) == Dll::g_currentModule)
 		{
 			Compat::Log() << "ERROR: Target function is already hooked: " << funcName;
@@ -177,7 +181,8 @@ namespace
 			totalInstructionSize += instructionSize;
 		}
 
-		LOG_DEBUG << "Decoded instructions: " << Compat::hexDump(targetFunc, totalInstructionSize);
+		LOG_DEBUG << "Hooking function: " << funcName
+			<< " (" << oss.str() << Compat::hexDump(targetFunc, totalInstructionSize) << ')';
 
 		BYTE* trampoline = static_cast<BYTE*>(
 			VirtualAlloc(nullptr, totalInstructionSize + 5, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE));
@@ -299,7 +304,7 @@ namespace Compat
 		HMODULE module = Compat::getModuleHandleFromAddress(funcPtr);
 		if (module)
 		{
-			oss << getModulePath(module).string() << "+0x" << std::hex <<
+			oss << getModulePath(module) << "+0x" << std::hex <<
 				reinterpret_cast<DWORD>(funcPtr) - reinterpret_cast<DWORD>(module);
 		}
 		else
diff --git a/DDrawCompat/D3dDdi/KernelModeThunks.cpp b/DDrawCompat/D3dDdi/KernelModeThunks.cpp
index d8fd9a0..7dffd28 100644
--- a/DDrawCompat/D3dDdi/KernelModeThunks.cpp
+++ b/DDrawCompat/D3dDdi/KernelModeThunks.cpp
@@ -292,7 +292,7 @@ namespace D3dDdi
 				CompatPtr<IDirectDraw7> dd7(ddUnk);
 
 				DDDEVICEIDENTIFIER2 di = {};
-				dd7->GetDeviceIdentifier(dd7, &di, 0);
+				dd7.get()->lpVtbl->GetDeviceIdentifier(dd7, &di, 0);
 			}
 
 			return g_lastOpenAdapterInfo.monitorRect;