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Function luaH_newkey

3rd/lua-5.4.3/src/ltable.c:654–708  ·  view source on GitHub ↗

** inserts a new key into a hash table; first, check whether key's main ** position is free. If not, check whether colliding node is in its main ** position or not: if it is not, move colliding node to an empty place and ** put new key in its main position; otherwise (colliding node is in its main ** position), new key goes to an empty position. */

Source from the content-addressed store, hash-verified

652** position), new key goes to an empty position.
653*/
654void luaH_newkey (lua_State *L, Table *t, const TValue *key, TValue *value) {
655 Node *mp;
656 TValue aux;
657 if (l_unlikely(ttisnil(key)))
658 luaG_runerror(L, "table index is nil");
659 else if (ttisfloat(key)) {
660 lua_Number f = fltvalue(key);
661 lua_Integer k;
662 if (luaV_flttointeger(f, &k, F2Ieq)) { /* does key fit in an integer? */
663 setivalue(&aux, k);
664 key = &aux; /* insert it as an integer */
665 }
666 else if (l_unlikely(luai_numisnan(f)))
667 luaG_runerror(L, "table index is NaN");
668 }
669 if (ttisnil(value))
670 return; /* do not insert nil values */
671 mp = mainpositionTV(t, key);
672 if (!isempty(gval(mp)) || isdummy(t)) { /* main position is taken? */
673 Node *othern;
674 Node *f = getfreepos(t); /* get a free place */
675 if (f == NULL) { /* cannot find a free place? */
676 rehash(L, t, key); /* grow table */
677 /* whatever called 'newkey' takes care of TM cache */
678 luaH_set(L, t, key, value); /* insert key into grown table */
679 return;
680 }
681 lua_assert(!isdummy(t));
682 othern = mainposition(t, keytt(mp), &keyval(mp));
683 if (othern != mp) { /* is colliding node out of its main position? */
684 /* yes; move colliding node into free position */
685 while (othern + gnext(othern) != mp) /* find previous */
686 othern += gnext(othern);
687 gnext(othern) = cast_int(f - othern); /* rechain to point to 'f' */
688 *f = *mp; /* copy colliding node into free pos. (mp->next also goes) */
689 if (gnext(mp) != 0) {
690 gnext(f) += cast_int(mp - f); /* correct 'next' */
691 gnext(mp) = 0; /* now 'mp' is free */
692 }
693 setempty(gval(mp));
694 }
695 else { /* colliding node is in its own main position */
696 /* new node will go into free position */
697 if (gnext(mp) != 0)
698 gnext(f) = cast_int((mp + gnext(mp)) - f); /* chain new position */
699 else lua_assert(gnext(f) == 0);
700 gnext(mp) = cast_int(f - mp);
701 mp = f;
702 }
703 }
704 setnodekey(L, mp, key);
705 luaC_barrierback(L, obj2gco(t), key);
706 lua_assert(isempty(gval(mp)));
707 setobj2t(L, gval(mp), value);
708}
709
710
711/*

Callers 2

luaH_finishsetFunction · 0.85
luaH_setintFunction · 0.85

Calls 7

luaG_runerrorFunction · 0.85
luaV_flttointegerFunction · 0.85
mainpositionTVFunction · 0.85
getfreeposFunction · 0.85
rehashFunction · 0.85
luaH_setFunction · 0.85
mainpositionFunction · 0.85

Tested by

no test coverage detected