Function atomic

Source/Misc/lua/src/lua.c:6527–6555

static void atomic (lua_State *L) {
global_State *g = G(L);
size_t udsize;  /* total size of userdata to be finalized */
/* remark occasional upvalues of (maybe) dead threads */
remarkupvals(g);
/* traverse objects cautch by write barrier and by 'remarkupvals' */
propagateall(g);
/* remark weak tables */
g->gray = g->weak;
g->weak = NULL;
lua_assert(!iswhite(obj2gco(g->mainthread)));
markobject(g, L);  /* mark running thread */
markmt(g);  /* mark basic metatables (again) */
propagateall(g);
/* remark gray again */
g->gray = g->grayagain;
g->grayagain = NULL;
propagateall(g);
udsize = luaC_separateudata(L, 0);  /* separate userdata to be finalized */
marktmu(g);  /* mark `preserved' userdata */
udsize += propagateall(g);  /* remark, to propagate `preserveness' */
cleartable(g->weak);  /* remove collected objects from weak tables */
/* flip current white */
g->currentwhite = cast_byte(otherwhite(g));
g->sweepstrgc = 0;
g->sweepgc = &g->rootgc;
g->gcstate = GCSsweepstring;
g->estimate = g->totalbytes - udsize;  /* first estimate */
}


static l_mem singlestep (lua_State *L) {