Function precallC

xrepo/packages/l/lua/port/lua/src/ldo.c:493–511

** precall for C functions */

** precall for C functions
*/
l_sinline int precallC (lua_State *L, StkId func, int nresults,
                                            lua_CFunction f) {
  int n;  /* number of returns */
  CallInfo *ci;
  checkstackGCp(L, LUA_MINSTACK, func);  /* ensure minimum stack size */
  L->ci = ci = prepCallInfo(L, func, nresults, CIST_C,
                               L->top + LUA_MINSTACK);
  lua_assert(ci->top <= L->stack_last);
  if (l_unlikely(L->hookmask & LUA_MASKCALL)) {
    int narg = cast_int(L->top - func) - 1;
    luaD_hook(L, LUA_HOOKCALL, -1, 1, narg);
  }
  lua_unlock(L);
  n = (*f)(L);  /* do the actual call */
  lua_lock(L);
  api_checknelems(L, n);
  luaD_poscall(L, ci, n);
  return n;
}


/*