490 static int costatus (lua_State *L, lua_State *co) {  in costatus()  argument
491   if (L == co) return CO_RUN;  in costatus()
492   switch (lua_status(co)) {  in costatus()
497       if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */  in costatus()
499       else if (lua_gettop(co) == 0)  in costatus()
511   lua_State *co = lua_tothread(L, 1);  in luaB_costatus()  local
512   luaL_argcheck(L, co, 1, "coroutine expected");  in luaB_costatus()
513   lua_pushstring(L, statnames[costatus(L, co)]);  in luaB_costatus()
518 static int auxresume (lua_State *L, lua_State *co, int narg) {  in auxresume()  argument
519   int status = costatus(L, co);  in auxresume()
520   if (!lua_checkstack(co, narg))  in auxresume()
526   lua_xmove(L, co, narg);  in auxresume()
527   lua_setlevel(L, co);  in auxresume()
528   status = lua_resume(co, narg);  in auxresume()
530     int nres = lua_gettop(co);  in auxresume()
533     lua_xmove(co, L, nres);  /* move yielded values */  in auxresume()
537     lua_xmove(co, L, 1);  /* move error message */  in auxresume()
544   lua_State *co = lua_tothread(L, 1);  in luaB_coresume()  local
546   luaL_argcheck(L, co, 1, "coroutine expected");  in luaB_coresume()
547   r = auxresume(L, co, lua_gettop(L) - 1);  in luaB_coresume()
562   lua_State *co = lua_tothread(L, lua_upvalueindex(1));  in luaB_auxwrap()  local
563   int r = auxresume(L, co, lua_gettop(L));  in luaB_auxwrap()