Add sanity checks and logs when patching KAGE::StartupEngine from the…

… loader

libzhl/ASMPatcher.cpp

@@ -52,10 +52,14 @@ void* ASMPatcher::PatchFromSig(const char* sig, const char* with) {
 	return PatchAt(scan.GetAddress(), with);
 }
 
-void* ASMPatcher::PatchAt(void* at, ASMPatch* with) {
+void* ASMPatcher::PatchAt(void* at, ASMPatch* with, size_t* len) {
 	void* targetPage = GetAllocPage(with->Length(), true);
 	std::unique_ptr<char[]> text = with->ToASM(targetPage);
-	return Patch(at, targetPage, text.get(), with->Length());
+	size_t patchLen = with->Length();
+	if (len) {
+		*len = patchLen;
+	}
+	return Patch(at, targetPage, text.get(), patchLen);
 }
 
 void* ASMPatcher::PatchAt(void* at, const char* with, size_t len) {

libzhl/ASMPatcher.hpp

@@ -20,7 +20,7 @@
 #include "libzhl.h"
 
 extern "C" {
-	__declspec(dllexport) int InitZHL(void (*ptr)());
+	__declspec(dllexport) int InitZHL(void (__stdcall*ptr)());
 }
 
 class LIBZHL_API ASMPatcher
@@ -72,7 +72,7 @@ class LIBZHL_API ASMPatcher
 	void* AttemptPatchFunction(const char* beginSig, const char* endSig, const char* patchSig, const char* with);
 	void* PatchFromSig(const char* sig, const char* with);
 	void* PatchAt(void* at, const char* with, size_t len = 0);
-	void* PatchAt(void* at, ASMPatch* with);
+	void* PatchAt(void* at, ASMPatch* with, size_t* len = NULL);
 	void* Patch(void* at, void* page, const char* with, size_t len);
 
 	void FlatPatch(void* at, ASMPatch* with, bool nopRest = false);
@@ -222,7 +222,7 @@ class LIBZHL_API ASMPatch
 
 	private:
 		friend ASMPatch;
-		friend __declspec(dllexport) int InitZHL(void (*ptr)());
+		friend __declspec(dllexport) int InitZHL(void (__stdcall*ptr)());
 
 		void Restore();
 		uint32_t GetMask() const;
@@ -467,7 +467,7 @@ class LIBZHL_API ASMPatch
 		void* _target;
 	};
 
-	friend __declspec(dllexport) int InitZHL(void (*ptr)());
+	friend __declspec(dllexport) int InitZHL(void (__stdcall*ptr)());
 	static void _Init();
 
 	uint8_t RegisterTox86(Registers reg);

libzhl/dllmain.cpp

@@ -15,7 +15,11 @@
 #include <filesystem>
 #include <sstream>
 
-void (*loaderFinish)() = NULL;
+void (__stdcall*loaderFinish)() = NULL;
+
+void __stdcall SanityCheckInitZHL() {
+	ZHL::Log("SanityCheckInitZHL: patch should be okay\n");
+}
 
 /* Because ZHL is not initialized when we enter InitZHL, we cannot hook 
  * anything, so we need to ASM patch instead.
@@ -29,22 +33,31 @@ void HookMain() {
 	char* movOffsetAddr = (char*)addr + 0x3;
 	void* movOffsetValue;
 	memcpy(&movOffsetValue, movOffsetAddr, 0x4);
-	printf("Found KAGE::EngineStartup hook address %p\n", addr);
+	ZHL::Log("Found KAGE::EngineStartup call address %p\n", addr);
+	ZHL::Log("Dumping ASM: ");
+	ZHL::DumpMemory(addr, 0x20, false, true);
 	ASMPatch patch;
 	ASMPatch::SavedRegisters registers(ASMPatch::SavedRegisters::GP_REGISTERS_STACKLESS, true);
 	patch.PreserveRegisters(registers);
+	patch.AddInternalCall(SanityCheckInitZHL);
 	patch.AddInternalCall(loaderFinish);
 	patch.RestoreRegisters(registers);
 	ByteBuffer buffer;
 	buffer.AddString("\x32\xd2\xb9");
 	buffer.AddPointer(movOffsetValue);
 	patch.AddBytes(buffer);
 	patch.AddRelativeJump((char*)addr + 0x7);
-	sASMPatcher.PatchAt(addr, &patch);
+	size_t patchLen = 0;
+	void* patchedAddr = sASMPatcher.PatchAt(addr, &patch, &patchLen);
+
+	ZHL::Log("Dumping ASM of the call to KAGE::Engine post patch: ");
+	ZHL::DumpMemory(addr, 0x20, false, true);
+	ZHL::Log("Dumping ASM of the patch: ");
+	ZHL::DumpMemory(patchedAddr, patchLen, false, true);
 }
 
 extern "C" {
-	__declspec(dllexport) int InitZHL(void (*loaderFinishPtr)())
+	__declspec(dllexport) int InitZHL(void (__stdcall*loaderFinishPtr)())
 	{
 #ifdef ZHL_LOG_FILE
 		std::ofstream f(ZHL_LOG_FILE, std::ios_base::app);
@@ -58,6 +71,7 @@ extern "C" {
 			ExitProcess(1);
 		}
 #endif
+		ZHL::ClearLogFile();
 		if (!FunctionDefinition::Init())
 		{
 			auto const& missing = Definition::GetMissing();

loader/loader.cpp

@@ -120,7 +120,7 @@ DWORD RedirectLua(FILE* f, HMODULE* outLua) {
 
 static HMODULE luaHandle = NULL;
 
-void LoadMods() {
+void __stdcall LoadMods() {
 	FILE* f = fopen("zhlLoader.log", "a");
 	Log(f, "INFO", "Loading mods...\n");
 
@@ -192,7 +192,7 @@ extern "C" {
 		Log(f, "INFO", "Loaded ZHL at %p\n", zhl);
 		Log(f, "INFO", "Search InitZHL in ZHL\n");
 
-		int (*initZhl)(void (*)()) = (int(*)(void(*)()))GetProcAddress(zhl, "InitZHL");
+		int (*initZhl)(void (__stdcall*)()) = (int(*)(void(__stdcall*)()))GetProcAddress(zhl, "InitZHL");
 		if (!initZhl) {
 			FreeLibrary(zhl);
 			Log(f, "ERROR", "InitZHL not found\n");

repentogon/dllmain.cpp

@@ -166,7 +166,6 @@ char REPENTOGON::moddedtitle[256] = "";
 // This small function loads all the hooks and must be present in every mod
 MOD_EXPORT int ModInit(int argc, char** argv)
 {
-	ZHL::ClearLogFile();
 	ZHL::Logger logger(true);
 	logger.Log("REPENTOGON: ModInit\n");