how to call c dll from latest lua 5.3 - c

Question

UPDATED: Problem solved. The dll must not be statically linking to lua, otherwise it crashes with a multiple Lua VMs detected exception. The code blow actually works fine, just leave it here in case someone got this problem too.
And wireshark uses lua5.2 because there's a "lua52.dll" in it's folder.
I'm writing wireshark plugin, some algorithm in C is difficult to implement in Lua, so I try to use these algorithm through dll.
Most examples online use the old version of Lua, which use luaL_register in the dll code. The luaL_register is replaced by lua_newtable/luaL_setfuncs in newer version, but I didn't find any working example online.
Here's what I tried :
#include <stdio.h>
#include <string.h>
#include "lua.hpp"
#include <windows.h>
extern "C" {
static int add(lua_State* L)
{
MessageBox(0, "", "", 0);
double op1 = luaL_checknumber(L,1);
double op2 = luaL_checknumber(L,2);
lua_pushnumber(L,op1 + op2);
return 1;
}
static luaL_Reg mylibs[] = {
{"add", add},
{0, 0}
};
__declspec(dllexport)
int luaopen_mylib(lua_State* L)
{
lua_newtable(L);
luaL_setfuncs(L, mylibs, 0);
lua_setglobal(L, "mylib");
return 1;
}
}
and the lua code:
require "mylib" -- <----------crashes
-- local mylib = package.loadlib("mylib.dll","luaopen_mylib");
print (mylib)
if(mylib)then
--mylib();
else
-- Error
end
local b=mylib.add(11,33);
print("sum:", b);
The lua code crashes at first line. How to fix it?
Another question, how to verify which version of Lua is wireshark using? Calling print(_VERSION) in wireshark's lua console, it shows nothing.

Answer 1

The crash occurs when statically linking to lua.lib, I guess there is already a lua VM in lua.lib, so use dynamic linking and the problem is gone.