Properly implementing GameDLL unloading.

core-legacy/gamedll_bridge.cpp

@@ -34,8 +34,17 @@ public:
 		LoadAsGameDLL(info);
 		return true;
 	}
-	virtual void DLLInit_Post()
+	virtual void DLLInit_Post(int *isgdUnload)
 	{
+		SourceHook::MemFuncInfo mfi;
+
+		mfi.isVirtual = false;
+		SourceHook::GetFuncInfo(&IServerGameDLL::DLLShutdown, mfi);
+		assert(mfi.isVirtual);
+		assert(mfi.vtbloffs == 0);
+		assert(mfi.thisptroffs == 0);
+		*isgdUnload = mfi.vtblindex;
+
 		g_PluginMngr.SetAllLoaded();
 	}
 	virtual void *QueryInterface(const char *iface, int *ret)
@@ -53,6 +62,7 @@ public:
 	}
 	virtual void Unload()
 	{
+		UnloadMetamod(true);
 	}
 };
 

core-legacy/sourcemm.cpp

@@ -32,13 +32,11 @@ using namespace SourceMM;
 #undef CommandLine
 DLL_IMPORT ICommandLine *CommandLine();
 
-SH_DECL_HOOK0_void(IServerGameDLL, DLLShutdown, SH_NOATTRIB, false);
 SH_DECL_HOOK0_void(IServerGameDLL, LevelShutdown, SH_NOATTRIB, false);
 SH_DECL_HOOK6(IServerGameDLL, LevelInit, SH_NOATTRIB, false, bool, const char *, const char *, const char *, const char *, bool, bool);
 SH_DECL_HOOK1_void(IServerGameClients, ClientCommand, SH_NOATTRIB, 0, edict_t *);
 SH_DECL_HOOK0(IServerGameDLL, GameInit, SH_NOATTRIB, false, bool);
 
-void DLLShutdown_handler();
 void LevelShutdown_handler();
 bool LevelInit_handler(char const *pMapName,
 					   char const *pMapEntities,
@@ -101,7 +99,6 @@ void InitMainStates()
 	abspath(smm_path, game_dir);
 	g_ModPath.assign(smm_path);
 
-	SH_ADD_HOOK_STATICFUNC(IServerGameDLL, DLLShutdown, g_GameDll.pGameDLL, DLLShutdown_handler, false);
 	SH_ADD_HOOK_STATICFUNC(IServerGameDLL, LevelShutdown, g_GameDll.pGameDLL, LevelShutdown_handler, true);
 	SH_ADD_HOOK_STATICFUNC(IServerGameDLL, LevelInit, g_GameDll.pGameDLL, LevelInit_handler, true);
 	SH_ADD_HOOK_STATICFUNC(IServerGameDLL, GameInit, g_GameDll.pGameDLL, GameInit_handler, false);
@@ -304,8 +301,6 @@ void UnloadMetamod(bool shutting_down)
 		/* Add the FCVAR_GAMEDLL flag to our cvars so the engine removes them properly */
 		g_SMConVarAccessor.MarkCommandsAsGameDLL();
 		g_Engine.icvar->UnlinkVariables(FCVAR_GAMEDLL);
-
-		SH_CALL(g_GameDllPatch, &IServerGameDLL::DLLShutdown)();
 	}
 
 	SH_RELEASE_CALLCLASS(g_GameDllPatch);
@@ -316,12 +311,6 @@ void UnloadMetamod(bool shutting_down)
 	g_SourceHook.CompleteShutdown();
 }
 
-void DLLShutdown_handler()
-{
-	UnloadMetamod(true);
-	RETURN_META(MRES_SUPERCEDE);
-}
-
 void LoadFromVDF(const char *file)
 {
 	PluginId id;

loader/gamedll.cpp

@@ -25,6 +25,7 @@ static void *gamedll_lib = NULL;
 static IServerGameDLL *gamedll_iface = NULL;
 static QueryValveInterface gamedll_qvi = NULL;
 static int gamedll_version = 0;
+static int isgd_shutdown_index = -1;
 
 #if defined _WIN32
 #define TIER0_NAME			"bin\\tier0.dll"
@@ -213,7 +214,11 @@ mm_FreeCachedLibraries()
 static void
 mm_PatchDllInit(bool patch);
 
-static void *isgd_orig_call = NULL;
+static void
+mm_PatchDllShutdown();
+
+static void *isgd_orig_init = NULL;
+static void *isgd_orig_shutdown = NULL;
 
 class VEmptyClass
 {
@@ -286,7 +291,7 @@ public:
 #if defined _WIN32
 				void *addr;
 			} u;
-			u.addr = isgd_orig_call;
+			u.addr = isgd_orig_init;
 #else
 				struct
 				{
@@ -294,7 +299,7 @@ public:
 					intptr_t adjustor;
 				} s;
 			} u;
-			u.s.addr = isgd_orig_call;
+			u.s.addr = isgd_orig_init;
 			u.s.adjustor = 0;
 #endif
 			result = (((VEmptyClass *)gamedll_iface)->*u.mfpnew)(engineFactory,
@@ -316,13 +321,47 @@ public:
 		}
 		else if (gamedll_bridge != NULL)
 		{
-			gamedll_bridge->DLLInit_Post();
+			gamedll_bridge->DLLInit_Post(&isgd_shutdown_index);
+			assert(isgd_shutdown_index != -1);
+			mm_PatchDllShutdown();
 		}
 
 		mm_PatchDllInit(false);
 
 		return result;
 	}
+
+	virtual void DLLShutdown()
+	{
+		gamedll_bridge->Unload();
+		gamedll_bridge = NULL;
+		mm_UnloadMetamodLibrary();
+
+		/* Call original function */
+		{
+			union
+			{
+				void (VEmptyClass::*mfpnew)();
+#if defined _WIN32
+				void *addr;
+			} u;
+			u.addr = isgd_orig_shutdown;
+#else
+				struct
+				{
+					void *addr;
+					intptr_t adjustor;
+				} s;
+			} u;
+			u.s.addr = isgd_orig_shutdown;
+			u.s.adjustor = 0;
+#endif
+			(((VEmptyClass *)gamedll_iface)->*u.mfpnew)();
+		}
+
+		mm_UnloadLibrary(gamedll_lib);
+		gamedll_lib = NULL;
+	}
 };
 
 static IServerGameDLL isgd_thunk;
@@ -349,18 +388,38 @@ mm_PatchDllInit(bool patch)
 
 	if (patch)
 	{
-		assert(isgd_orig_call == NULL);
-		isgd_orig_call = vtable_dest[mfp.vtblindex];
+		assert(isgd_orig_init == NULL);
+		isgd_orig_init = vtable_dest[mfp.vtblindex];
 		vtable_dest[mfp.vtblindex] = vtable_src[mfp.vtblindex];
 	}
 	else
 	{
-		assert(isgd_orig_call != NULL);
-		vtable_dest[mfp.vtblindex] = isgd_orig_call;
-		isgd_orig_call = NULL;
+		assert(isgd_orig_init != NULL);
+		vtable_dest[mfp.vtblindex] = isgd_orig_init;
+		isgd_orig_init = NULL;
 	}
 }
 
+static void
+mm_PatchDllShutdown()
+{
+	void **vtable_src;
+	void **vtable_dest;
+	SourceHook::MemFuncInfo mfp;
+
+	mfp.isVirtual = false;
+	SourceHook::GetFuncInfo(&IServerGameDLL::DLLShutdown, mfp);
+	assert(mfp.isVirtual);
+	assert(mfp.thisptroffs == 0);
+	assert(mfp.vtbloffs == 0);
+
+	vtable_src = (void **)*(void **)&isgd_thunk;
+	vtable_dest = (void **)*(void **)gamedll_iface;
+
+	isgd_orig_shutdown = vtable_dest[isgd_shutdown_index];
+	vtable_dest[isgd_shutdown_index] = vtable_src[mfp.vtblindex];
+}
+
 static void
 mm_PrepForGameLoad()
 {

loader/loader_bridge.h

@@ -35,7 +35,7 @@ class IGameDllBridge
 {
 public:
 	virtual bool DLLInit_Pre(const gamedll_bridge_info *info, char *buffer, size_t maxlength) = 0;
-	virtual void DLLInit_Post() = 0;
+	virtual void DLLInit_Post(int *isgdUnload) = 0;
 	virtual void *QueryInterface(const char *name, int *ret) = 0;
 	virtual void Unload() = 0;
 };