luajit: get cdata to not conflict with gmod's vector type

Author: RaphaelIT7

LuaJIT-2.1/src/gmod.cpp

@@ -1,4 +1,9 @@
-#include "gmod.h"
+extern "C"
+{
+	#include "gmod.h"
+	#include "lua.h"
+}
+#include "stdio.h"
 
 namespace std
 {
@@ -200,18 +205,37 @@ extern "C" void lua_init_stack_gmod(lua_State* L1, lua_State* L)
 	}
 }
 
-extern "C" void GMOD_LuaPrint(const char* str, lua_State* L) // Idk how gmod does it
+extern "C" void GMOD_LuaPrint(const char* str, lua_State* L) // Should be how gmod does it
 {
+	if (!L->luabase) // except for this, gmod doesn't do this, but we do making testing jit less of a pain
+	{
+		printf(str);
+		return;
+	}
+
 	((ILuaInterface*)L->luabase)->Msg("%s", str);
 }
 
+struct UserData {
+	void* data;
+	unsigned char type;
+};
+
 extern "C" void GMOD_LuaCreateEmptyUserdata(lua_State* L)
 {
 	//ILuaBase::UserData* udata = (ILuaBase::UserData*)((ILuaBase*)L->luabase)->NewUserdata(sizeof(ILuaBase::UserData)); // Gmod uses CLuaInterface::PushUserType(NULL, 7) Instead
 	//udata->data = nullptr;
 	//udata->type = 7; // 7 = Userdata
 
 	//return udata;
+
+	if (!L->luabase) // just to make testing easier. Gmod doesn't have this.
+	{
+		UserData* pData = (UserData*)lua_newuserdata(L, sizeof(ILuaBase::UserData));
+		pData->data = nullptr;
+		pData->type = 7;
+		return;
+	}
 
 
 	((ILuaBase*)L->luabase)->PushUserType(NULL, 7);

LuaJIT-2.1/src/lj_api.c

@@ -26,6 +26,9 @@
 #include "lj_strscan.h"
 #include "lj_strfmt.h"
 
+#include "lj_ctype.h"
+#include "lj_cconv.h"
+
 /* -- Common helper functions --------------------------------------------- */
 
 #define lj_checkapi_slot(idx) \
@@ -230,16 +233,18 @@ LUA_API int lua_type(lua_State *L, int idx)
 #endif
   } else if (o == niltv(L)) {
     return LUA_TNONE;
-  } else {  /* Magic internal/external tag conversion. ORDER LJ_T */
-    uint32_t t = ~itype(o);
+  } else if(tviscdata(o)) {
+    return LUA_TUSERDATA; // we would return 10 which conflicts with gmod!
+  }  /* Magic internal/external tag conversion. ORDER LJ_T */
+  
+  uint32_t t = ~itype(o);
 #if LJ_64
-    int tt = (int)((U64x(75a06,98042110) >> 4*t) & 15u);
+  int tt = (int)((U64x(75a06,98042110) >> 4*t) & 15u);
 #else
-    int tt = (int)(((t < 8 ? 0x98042110u : 0x75a06u) >> 4*(t&7)) & 15u);
+  int tt = (int)(((t < 8 ? 0x98042110u : 0x75a06u) >> 4*(t&7)) & 15u);
 #endif
-    lj_assertL(tt != LUA_TNIL || tvisnil(o), "bad tag conversion");
-    return tt;
-  }
+  lj_assertL(tt != LUA_TNIL || tvisnil(o), "bad tag conversion");
+  return tt;
 }
 
 LUALIB_API void luaL_checktype(lua_State *L, int idx, int tt)
@@ -257,25 +262,36 @@ LUALIB_API void luaL_checkany(lua_State *L, int idx)
 // Based off https://github.com/meepen/gluajit/blob/master/src/lj_api.c#L225-L247
 /*extern "C"*/ const char* GMODLUA_GetUserType(lua_State* L, int iStackPos)
 {
-	static char strName[128];
-	const char* strTypeName = "UserData";
-	if (lua_getmetatable(L, iStackPos))
-	{
-		lua_pushstring(L, "MetaName");
-		lua_gettable(L, -2);
-
-		if (lua_isstring(L, -1))
-		{
-			strncpy(strName, lua_tostring(L, -1), sizeof(strName));
-			strTypeName = strName;
-		}
+  static char strName[128];
+  const char* strTypeName = "UserData";
+  cTValue *o = index2adr(L, iStackPos);
+  GCtab *mt = NULL;
+  if (tvistab(o))
+    mt = tabref(tabV(o)->metatable);
+  else if (tvisudata(o))
+    mt = tabref(udataV(o)->metatable);
+  else if (tviscdata(o))
+  {
+    CTState *cts = ctype_cts(L);
+    CType *ct = ctype_raw(cts, cdataV(o)->ctypeid);
+    mt = tabV(lj_tab_getinth(cts->miscmap, -(int32_t)ctype_typeid(cts, ct)));
+  } else
+    mt = tabref(basemt_obj(G(L), o));
 
-		lua_pop(L, 1);
-	}
+  if (mt)
+  {
+    GCstr* str = lj_str_newz(L, "MetaName");
+    cTValue* val = lj_tab_getstr(mt, str);
+    lj_str_free(G(L), str);
 
-	lua_pop(L, 1);
+    if (val && tvisstr(val))
+    {
+      strncpy(strName, strdata(strV(val)), sizeof(strName));
+      strTypeName = strName;
+    }
+  }
 
-	return strTypeName;
+  return strTypeName;
 }
 
 LUA_API const char *lua_typename(lua_State *L, int t, int stackpos)