void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t);
TValue *oldval = cast(TValue *, luaH_get(h, key));
/* if previous value is not nil, there must be a previous entry
in the table; moreover, a metamethod has no relevance */
if (!ttisnil(oldval) ||
/* previous value is nil; must check the metamethod */
((tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL &&
/* no metamethod; is there a previous entry in the table? */
(oldval != luaO_nilobject ||
/* no previous entry; must create one. (The next test is
always true; we only need the assignment.) */
(oldval = luaH_newkey(L, h, key), 1)))) {
/* no metamethod and (now) there is an entry with given key */
setobj2t(L, oldval, val); /* assign new value to that entry */
invalidateTMcache(h);
luaC_barrierback(L, obj2gco(h), val);
return;
}
/* else will try the metamethod */
}
else /* not a table; check metamethod */
if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
/* there is a metamethod */
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val, 0);
return;
}
t = tm; /* else repeat with 'tm' */
}
void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
TValue temp;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t);
TValue *oldval = luaH_set(L, h, key); /* do a primitive set */
if (!ttisnil(oldval) || /* result is no nil? */
(tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
setobj2t(L, oldval, val);
luaC_barriert(L, h, val);
return;
}
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val);
return;
}
/* else repeat with `tm' */
setobj(L, &temp, tm); /* avoid pointing inside table (may rehash) */
t = &temp;
}
luaG_runerror(L, "loop in settable");
}
/*
* 获取哈希表
* L 虚拟机状态
* t 哈希表的指针
* key 哈希表的键
* val 哈希表的值在栈中的索引
*/
void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
/* 遍历 */
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
/* 如果t是哈希表类型 */
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t); /* 获取哈希表值 */
/* 从键中取出值 */
const TValue *res = luaH_get(h, key); /* do a primitive get */
/* 如果不是空值或者其表的元运算为空 */
if (!ttisnil(res) || /* result is not nil? */
(tm = fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */
/* 设置哈希值到指定的栈索引位置 */
setobj2s(L, val, res);
return;
}
/* else will try the tag method */
}
/* 如果t不是哈希表则判断其元运算是否为空值 */
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX)))
luaG_typeerror(L, t, "index");
/* 如果元运算是函数则进行调用 */
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val, 1);
return;
}
t = tm; /* else repeat with 'tm' */
}
luaG_runerror(L, "loop in gettable");
}
void luaV_settable (lua_State *L, TValue *t, TValue *key, StkId val) {
int loop;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
TValue *tm;
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t);
TValue *oldval = luaH_set(L, h, key); /* do a primitive set */
/* oldval is nil=> look for newindex, oldval is not nil => look for usedindex */
if (!((ttisnil(oldval) && ((tm = fasttm(L, h->metatable, TM_NEWINDEX)) != NULL)) ||
((!ttisnil(oldval)) && ((tm = fasttm(L, h->metatable, TM_USEDINDEX)) != NULL)))) {
setobj2t(L, oldval, val);
luaC_barriert(L, h, val);
return;
}
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val);
return;
}
t = tm; /* else repeat with `tm' */
}
luaG_runerror(L, "loop in settable");
}
//将t表中key对应的value放入栈中(val)
void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t);
const TValue *res = luaH_get(h, key); /* do a primitive get */
if (!ttisnil(res) || /* result is not nil? */
(tm = fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */
setobj2s(L, val, res);
return;
}
//else: 没找到，但该表有元表，则利用元方法来找，下一个loop会跳到ttisfunction分支里
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val, 1);
return;
}
t = tm; /* else repeat with 'tm' */
}
luaG_runerror(L, "loop in gettable");
}
void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t) || ttisrotable(t)) { /* `t' is a table? */
void *h = ttistable(t) ? hvalue(t) : rvalue(t);
TValue *oldval = ttistable(t) ? luaH_set(L, (Table*)h, key) : NULL; /* do a primitive set */
if ((oldval && !ttisnil(oldval)) || /* result is no nil? */
(tm = fasttm(L, ttistable(t) ? ((Table*)h)->metatable : (Table*)luaR_getmeta(h), TM_NEWINDEX)) == NULL) { /* or no TM? */
if(oldval) {
setobj2t(L, oldval, val);
luaC_barriert(L, (Table*)h, val);
}
return;
}
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm) || ttislightfunction(tm)) {
callTM(L, tm, t, key, val);
return;
}
t = tm; /* else repeat with `tm' */
}
luaG_runerror(L, "loop in settable");
}
/*
** equality of Lua values. L == NULL means raw equality (no metamethods)
*/
int luaV_equalobj_ (lua_State *L, const TValue *t1, const TValue *t2) {
const TValue *tm;
lua_assert(ttisequal(t1, t2));
switch (ttype(t1)) {
case LUA_TNIL: return 1;
case LUA_TNUMBER: return luai_numeq(nvalue(t1), nvalue(t2));
case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2); /* true must be 1 !! */
case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
case LUA_TLCF: return fvalue(t1) == fvalue(t2);
case LUA_TSTRING: return eqstr(rawtsvalue(t1), rawtsvalue(t2));
case LUA_TUSERDATA: {
if (uvalue(t1) == uvalue(t2)) return 1;
else if (L == NULL) return 0;
tm = get_equalTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable, TM_EQ);
break; /* will try TM */
}
case LUA_TTABLE: {
if (hvalue(t1) == hvalue(t2)) return 1;
else if (L == NULL) return 0;
tm = get_equalTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ);
break; /* will try TM */
}
default:
lua_assert(iscollectable(t1));
return gcvalue(t1) == gcvalue(t2);
}
if (tm == NULL) return 0; /* no TM? */
callTM(L, tm, t1, t2, L->top, 1); /* call TM */
return !l_isfalse(L->top);
}
static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2,
StkId res, TMS event) {
const TValue *tm = luaT_gettmbyobj(L, p1, event); /* try first operand */
if (ttisnil(tm))
tm = luaT_gettmbyobj(L, p2, event); /* try second operand */
if (ttisnil(tm)) return 0;
callTM(L, tm, p1, p2, res, 1);
return 1;
}
void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
TValue tmp;
int loop;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t);
TValue *oldval = luaH_set(L, h, key); /* do a primitive set */
if (!ttisnil(oldval) || /* result is no nil? */
(tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
setobj2t(L, oldval, val);
luaC_barriert(L, h, val);
#if LUA_REFCOUNT
if (ttisnil(val)) {
Node* keyNode = luaH_getkey(h, key);
if (keyNode) {
luaH_removekey(L, h, keyNode);
}
}
#endif /* LUA_REFCOUNT */
return;
}
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val);
#if LUA_REFCOUNT
{
TValue *newval;
if (ttistable(t)) {
newval = luaH_set(L, hvalue(t), key);
if (ttisnil(newval)) {
Node* keyNode = luaH_getkey(hvalue(t), key);
if (keyNode)
luaH_removekey(L, hvalue(t), keyNode);
}
}
}
#endif /* LUA_REFCOUNT */
return;
}
setobj(L, &tmp, tm);
t = &tmp; /* else repeat with copy of `tm' */
}
luaG_runerror(L, "loop in settable");
}
void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
TValue temp;
setnilvalue(L->top);
L->top++;
fixedstack(L);
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t) || ttisrotable(t)) { /* `t' is a table? */
void *h = ttistable(t) ? hvalue(t) : rvalue(t);
TValue *oldval = ttistable(t) ? luaH_set(L, (Table*)h, key) : NULL; /* do a primitive set */
if ((oldval && !ttisnil(oldval)) || /* result is no nil? */
(tm = fasttm(L, ttistable(t) ? ((Table*)h)->metatable : (Table*)luaR_getmeta(h), TM_NEWINDEX)) == NULL) { /* or no TM? */
if(oldval) {
L->top--;
unfixedstack(L);
setobj2t(L, oldval, val);
((Table *)h)->flags = 0;
luaC_barriert(L, (Table*)h, val);
}
return;
}
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm) || ttislightfunction(tm)) {
L->top--;
unfixedstack(L);
callTM(L, tm, t, key, val);
return;
}
/* else repeat with `tm' */
setobj(L, &temp, tm); /* avoid pointing inside table (may rehash) */
t = &temp;
setobj2s(L, L->top-1, t); /* need to protect value from EGC. */
}
luaG_runerror(L, "loop in settable");
}
void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
const TValue *tm;
switch (ttypenv(rb)) {
case LUA_TTABLE: {
Table *h = hvalue(rb);
tm = fasttm(L, h->metatable, TM_LEN);
if (tm) break; /* metamethod? break switch to call it */
setnvalue(ra, cast_num(luaH_getn(h))); /* else primitive len */
return;
}
case LUA_TSTRING: {
setnvalue(ra, cast_num(tsvalue(rb)->len));
return;
}
default: { /* try metamethod */
tm = luaT_gettmbyobj(L, rb, TM_LEN);
if (ttisnil(tm)) /* no metamethod? */
luaG_typeerror(L, rb, "get length of");
break;
}
}
callTM(L, tm, rb, rb, ra, 1);
}
/*
** Receives table at `t', key at `key' and value at `val'.
*/
void luaV_settable (lua_State *L, const TObject *t, TObject *key, StkId val) {
const TObject *tm;
int loop = 0;
do {
if (ttistable(t)) { /* `t' is a table? */
Table *h = hvalue(t);
TObject *oldval = luaH_set(L, h, key); /* do a primitive set */
if (!ttisnil(oldval) || /* result is no nil? */
(tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
setobj2t(oldval, val); /* write barrier */
return;
}
/* else will try the tag method */
}
else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
luaG_typeerror(L, t, "index");
if (ttisfunction(tm)) {
callTM(L, tm, t, key, val);
return;
}
t = tm; /* else repeat with `tm' */
} while (++loop <= MAXTAGLOOP);
luaG_runerror(L, "loop in settable");
}
void killaV_gettable (killa_State *L, const killa_TValue *t, killa_TValue *key, killa_StkId val) {
int loop;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const killa_TValue *tm;
if (killa_ttistable(t)) { /* `t' is a table? */
killa_Table *h = killa_hvalue(t);
const killa_TValue *res = killaH_get(h, key); /* do a primitive get */
if (!killa_ttisnil(res) || /* result is not nil? */
(tm = killa_fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */
killa_setobj2s(L, val, res);
return;
}
/* else will try the tag method */
}
else if (killa_ttisnil(tm = killaT_gettmbyobj(L, t, TM_INDEX)))
killaG_typeerror(L, t, "index");
if (killa_ttisfunction(tm)) {
callTM(L, tm, t, key, val, 1);
return;
}
t = tm; /* else repeat with 'tm' */
}
killaG_runerror(L, "loop in gettable");
}