Replace LUA_PushLightUserdata with LUA_PushUserdata

See 7df6a309 and 83a87042. I didn't realize that light
userdata's metatable is shared--like numbers or strings.
So it cannot be paired with a metatable.

I also made a few minor tweaks to Lua cvars, other than
accounting for the double pointer in the userdata.

src/command.c

@@ -1577,7 +1577,7 @@ finish:
 	}
 	var->flags |= CV_MODIFIED;
 	// raise 'on change' code
-	LUA_CVarChanged(var->name); // let consolelib know what cvar this is.
+	LUA_CVarChanged(var); // let consolelib know what cvar this is.
 	if (var->flags & CV_CALL && !stealth)
 		var->func();
 

src/lua_consolelib.c

@@ -28,7 +28,7 @@ return luaL_error(L, "HUD rendering code should not call this function!");
 #define NOHOOK if (!lua_lumploading)\
 		return luaL_error(L, "This function cannot be called from within a hook or coroutine!");
 
-static const char *cvname = NULL;
+static consvar_t *this_cvar;
 
 void Got_Luacmd(UINT8 **cp, INT32 playernum)
 {
@@ -273,16 +273,13 @@ static int lib_comBufInsertText(lua_State *L)
 	return 0;
 }
 
-void LUA_CVarChanged(const char *name)
+void LUA_CVarChanged(void *cvar)
 {
-	cvname = name;
+	this_cvar = cvar;
 }
 
 static void Lua_OnChange(void)
 {
-	I_Assert(gL != NULL);
-	I_Assert(cvname != NULL);
-
 	/// \todo Network this! XD_LUAVAR
 
 	lua_pushcfunction(gL, LUA_GetErrorMessage);
@@ -291,13 +288,10 @@ static void Lua_OnChange(void)
 	// From CV_OnChange registry field, get the function for this cvar by name.
 	lua_getfield(gL, LUA_REGISTRYINDEX, "CV_OnChange");
 	I_Assert(lua_istable(gL, -1));
-	lua_getfield(gL, -1, cvname); // get function
+	lua_pushlightuserdata(gL, this_cvar);
+	lua_rawget(gL, -2); // get function
 
-	// From the CV_Vars registry field, get the cvar's userdata by name.
+	LUA_RawPushUserdata(gL, this_cvar);
-	lua_getfield(gL, LUA_REGISTRYINDEX, "CV_Vars");
-	I_Assert(lua_istable(gL, -1));
-	lua_getfield(gL, -1, cvname); // get consvar_t* userdata.
-	lua_remove(gL, -2); // pop the CV_Vars table.
 
 	LUA_Call(gL, 1, 0, 1); // call function(cvar)
 	lua_pop(gL, 1); // pop CV_OnChange table
@@ -312,15 +306,12 @@ static int lib_cvRegisterVar(lua_State *L)
 	luaL_checktype(L, 1, LUA_TTABLE);
 	lua_settop(L, 1); // Clear out all other possible arguments, leaving only the first one.
 	NOHOOK
-	cvar = lua_newuserdata(L, sizeof(consvar_t));
+	cvar = ZZ_Calloc(sizeof(consvar_t));
-	luaL_getmetatable(L, META_CVAR);
+	LUA_PushUserdata(L, cvar, META_CVAR);
-	lua_setmetatable(L, -2);
 
 #define FIELDERROR(f, e) luaL_error(L, "bad value for " LUA_QL(f) " in table passed to " LUA_QL("CV_RegisterVar") " (%s)", e);
 #define TYPEERROR(f, t) FIELDERROR(f, va("%s expected, got %s", lua_typename(L, t), luaL_typename(L, -1)))
 
-	memset(cvar, 0x00, sizeof(consvar_t)); // zero everything by default
-
 	lua_pushnil(L);
 	while (lua_next(L, 1)) {
 		// stack: cvar table, cvar userdata, key/index, value
@@ -369,7 +360,7 @@ static int lib_cvRegisterVar(lua_State *L)
 
 				lua_getfield(L, LUA_REGISTRYINDEX, "CV_PossibleValue");
 				I_Assert(lua_istable(L, 5));
-				lua_pushvalue(L, 2); // cvar userdata
+				lua_pushlightuserdata(L, cvar);
 				cvpv = lua_newuserdata(L, sizeof(CV_PossibleValue_t) * (count+1));
 				lua_rawset(L, 5);
 				lua_pop(L, 1); // pop CV_PossibleValue registry table
@@ -397,8 +388,9 @@ static int lib_cvRegisterVar(lua_State *L)
 				TYPEERROR("func", LUA_TFUNCTION)
 			lua_getfield(L, LUA_REGISTRYINDEX, "CV_OnChange");
 			I_Assert(lua_istable(L, 5));
+			lua_pushlightuserdata(L, cvar);
 			lua_pushvalue(L, 4);
-			lua_setfield(L, 5, cvar->name);
+			lua_rawset(L, 5);
 			lua_pop(L, 1);
 			cvar->func = Lua_OnChange;
 		}
@@ -415,19 +407,6 @@ static int lib_cvRegisterVar(lua_State *L)
 	if ((cvar->flags & CV_CALL) && !cvar->func)
 		return luaL_error(L, M_GetText("Variable %s has CV_CALL without a function\n"), cvar->name);
 
-	// stack: cvar table, cvar userdata
-	lua_getfield(L, LUA_REGISTRYINDEX, "CV_Vars");
-	I_Assert(lua_istable(L, 3));
-
-	lua_getfield(L, 3, cvar->name);
-	if (lua_type(L, -1) != LUA_TNIL)
-		return luaL_error(L, M_GetText("Variable %s is already defined\n"), cvar->name);
-	lua_pop(L, 1);
-
-	lua_pushvalue(L, 2);
-	lua_setfield(L, 3, cvar->name);
-	lua_pop(L, 1);
-
 	// actually time to register it to the console now! Finally!
 	cvar->flags |= CV_MODIFIED;
 	CV_RegisterVar(cvar);
@@ -440,22 +419,9 @@ static int lib_cvRegisterVar(lua_State *L)
 
 static int lib_cvFindVar(lua_State *L)
 {
-	consvar_t *cv;
+	const char *name = luaL_checkstring(L, 1);
-	if (( cv = CV_FindVar(luaL_checkstring(L,1)) ))
+	LUA_PushUserdata(L, CV_FindVar(name), META_CVAR);
-	{
-		lua_settop(L,1);/* We only want one argument in the stack. */
-		lua_pushlightuserdata(L, cv);/* Now the second value on stack. */
-		luaL_getmetatable(L, META_CVAR);
-		/*
-		The metatable is the last value on the stack, so this
-		applies it to the second value, which is the cvar.
-		*/
-		lua_setmetatable(L,2);
-		lua_pushvalue(L,2);
 	return 1;
-	}
-	else
-		return 0;
 }
 
 static int CVarSetFunction
@@ -464,7 +430,7 @@ static int CVarSetFunction
 		void (*Set)(consvar_t *, const char *),
 		void (*SetValue)(consvar_t *, INT32)
 ){
-	consvar_t *cvar = (consvar_t *)luaL_checkudata(L, 1, META_CVAR);
+	consvar_t *cvar = *(consvar_t **)luaL_checkudata(L, 1, META_CVAR);
 
 	if (cvar->flags & CV_NOLUA)
 		return luaL_error(L, "Variable %s cannot be set from Lua.", cvar->name);
@@ -496,7 +462,7 @@ static int lib_cvStealthSet(lua_State *L)
 
 static int lib_cvAddValue(lua_State *L)
 {
-	consvar_t *cvar = (consvar_t *)luaL_checkudata(L, 1, META_CVAR);
+	consvar_t *cvar = *(consvar_t **)luaL_checkudata(L, 1, META_CVAR);
 
 	if (cvar->flags & CV_NOLUA)
 		return luaL_error(L, "Variable %s cannot be set from Lua.", cvar->name);
@@ -555,7 +521,7 @@ static luaL_Reg lib[] = {
 
 static int cvar_get(lua_State *L)
 {
-	consvar_t *cvar = (consvar_t *)luaL_checkudata(L, 1, META_CVAR);
+	consvar_t *cvar = *(consvar_t **)luaL_checkudata(L, 1, META_CVAR);
 	const char *field = luaL_checkstring(L, 2);
 
 	if(fastcmp(field,"name"))

src/lua_script.h

@@ -56,7 +56,7 @@ void LUA_UnArchive(void);
 int LUA_PushGlobals(lua_State *L, const char *word);
 int LUA_CheckGlobals(lua_State *L, const char *word);
 void Got_Luacmd(UINT8 **cp, INT32 playernum); // lua_consolelib.c
-void LUA_CVarChanged(const char *name); // lua_consolelib.c
+void LUA_CVarChanged(void *cvar); // lua_consolelib.c
 int Lua_optoption(lua_State *L, int narg,
 	const char *def, const char *const lst[]);
 void LUAh_NetArchiveHook(lua_CFunction archFunc);

src/lua_skinlib.c

@@ -213,7 +213,7 @@ static int skin_get(lua_State *L)
 		lua_pushinteger(L, skin->availability);
 		break;
 	case skin_sprites:
-		LUA_PushLightUserdata(L, skin->sprites, META_SKINSPRITES);
+		LUA_PushUserdata(L, skin->sprites, META_SKINSPRITES);
 		break;
 	}
 	return 1;
@@ -336,13 +336,13 @@ static const char *const sprites_opt[] = {
 // skin.sprites[i] -> sprites[i]
 static int lib_getSkinSprite(lua_State *L)
 {
-	spritedef_t *sprites = (spritedef_t *)luaL_checkudata(L, 1, META_SKINSPRITES);
+	spritedef_t *sprites = *(spritedef_t **)luaL_checkudata(L, 1, META_SKINSPRITES);
 	playersprite_t i = luaL_checkinteger(L, 2);
 
 	if (i < 0 || i >= NUMPLAYERSPRITES*2)
 		return luaL_error(L, LUA_QL("skin_t") " field 'sprites' index %d out of range (0 - %d)", i, (NUMPLAYERSPRITES*2)-1);
 
-	LUA_PushLightUserdata(L, &sprites[i], META_SKINSPRITESLIST);
+	LUA_PushUserdata(L, &sprites[i], META_SKINSPRITESLIST);
 	return 1;
 }
 
@@ -355,7 +355,7 @@ static int lib_numSkinsSprites(lua_State *L)
 
 static int sprite_get(lua_State *L)
 {
-	spritedef_t *sprite = (spritedef_t *)luaL_checkudata(L, 1, META_SKINSPRITESLIST);
+	spritedef_t *sprite = *(spritedef_t **)luaL_checkudata(L, 1, META_SKINSPRITESLIST);
 	enum spritesopt field = luaL_checkoption(L, 2, NULL, sprites_opt);
 
 	switch (field)