Function auxupvalue

third-party/lua-5.2.4/src/ldblib.c:213–222

static int auxupvalue (lua_State *L, int get) {
  const char *name;
  int n = luaL_checkint(L, 2);
  luaL_checktype(L, 1, LUA_TFUNCTION);
  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
  if (name == NULL) return 0;
  lua_pushstring(L, name);
  lua_insert(L, -(get+1));
  return get + 1;
}


static int db_getupvalue (lua_State *L) {