int luaopen_upbtable(lua_State *L) {
lupb_newlib(L, "upb.table", lupbtable_toplevel_m);
// We define these here because they are not public (at least at the moment).
lupbtable_setfieldi(L, "CTYPE_PTR", UPB_CTYPE_PTR);
lupbtable_setfieldi(L, "CTYPE_INT32", UPB_CTYPE_INT32);
lua_pushlightuserdata(L, NULL);
lua_setfield(L, -2, "NULL");
return 1; // Return a single Lua value, the package table created above.
}
/* We store our module table in the registry, keyed by ptr.
* For more info about the motivation/rationale, see this thread:
* http://thread.gmane.org/gmane.comp.lang.lua.general/110632 */
bool lupb_openlib(lua_State *L, void *ptr, const char *name,
const luaL_Reg *funcs) {
/* Lookup cached module table. */
lua_pushlightuserdata(L, ptr);
lua_rawget(L, LUA_REGISTRYINDEX);
if (!lua_isnil(L, -1)) {
return true;
}
lupb_newlib(L, name, funcs);
/* Save module table in cache. */
lua_pushlightuserdata(L, ptr);
lua_pushvalue(L, -2);
lua_rawset(L, LUA_REGISTRYINDEX);
return false;
}
