1/*
2** $Id: lapi.c,v 2.259.1.2 2017/12/06 18:35:12 roberto Exp $
3** Lua API
4** See Copyright Notice in lua.h
5*/
6
7#define lapi_c
8#define LUA_CORE
9
10#include "lprefix.h"
11
12
13#include <stdarg.h>
14#include <string.h>
15
16#include "lua.h"
17
18#include "lapi.h"
19#include "ldebug.h"
20#include "ldo.h"
21#include "lfunc.h"
22#include "lgc.h"
23#include "lmem.h"
24#include "lobject.h"
25#include "lstate.h"
26#include "lstring.h"
27#include "ltable.h"
28#include "ltm.h"
29#include "lundump.h"
30#include "lvm.h"
31
32
33
34const char lua_ident[] =
35 "$LuaVersion: " LUA_COPYRIGHT " $"
36 "$LuaAuthors: " LUA_AUTHORS " $";
37
38
39/* value at a non-valid index */
40#define NONVALIDVALUE cast(TValue *, luaO_nilobject)
41
42/* corresponding test */
43#define isvalid(o) ((o) != luaO_nilobject)
44
45/* test for pseudo index */
46#define ispseudo(i) ((i) <= LUA_REGISTRYINDEX)
47
48/* test for upvalue */
49#define isupvalue(i) ((i) < LUA_REGISTRYINDEX)
50
51/* test for valid but not pseudo index */
52#define isstackindex(i, o) (isvalid(o) && !ispseudo(i))
53
54#define api_checkvalidindex(l,o) api_check(l, isvalid(o), "invalid index")
55
56#define api_checkstackindex(l, i, o) \
57 api_check(l, isstackindex(i, o), "index not in the stack")
58
59
60static TValue *index2addr (lua_State *L, int idx) {
61 CallInfo *ci = L->ci;
62 if (idx > 0) {
63 TValue *o = ci->func + idx;
64 api_check(L, idx <= ci->top - (ci->func + 1), "unacceptable index");
65 if (o >= L->top) return NONVALIDVALUE;
66 else return o;
67 }
68 else if (!ispseudo(idx)) { /* negative index */
69 api_check(L, idx != 0 && -idx <= L->top - (ci->func + 1), "invalid index");
70 return L->top + idx;
71 }
72 else if (idx == LUA_REGISTRYINDEX)
73 return &G(L)->l_registry;
74 else { /* upvalues */
75 idx = LUA_REGISTRYINDEX - idx;
76 api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large");
77 if (ttislcf(ci->func)) /* light C function? */
78 return NONVALIDVALUE; /* it has no upvalues */
79 else {
80 CClosure *func = clCvalue(ci->func);
81 return (idx <= func->nupvalues) ? &func->upvalue[idx-1] : NONVALIDVALUE;
82 }
83 }
84}
85
86
87/*
88** to be called by 'lua_checkstack' in protected mode, to grow stack
89** capturing memory errors
90*/
91static void growstack (lua_State *L, void *ud) {
92 int size = *(int *)ud;
93 luaD_growstack(L, size);
94}
95
96
97LUA_API int lua_checkstack (lua_State *L, int n) {
98 int res;
99 CallInfo *ci = L->ci;
100 lua_lock(L);
101 api_check(L, n >= 0, "negative 'n'");
102 if (L->stack_last - L->top > n) /* stack large enough? */
103 res = 1; /* yes; check is OK */
104 else { /* no; need to grow stack */
105 int inuse = cast_int(L->top - L->stack) + EXTRA_STACK;
106 if (inuse > LUAI_MAXSTACK - n) /* can grow without overflow? */
107 res = 0; /* no */
108 else /* try to grow stack */
109 res = (luaD_rawrunprotected(L, &growstack, &n) == LUA_OK);
110 }
111 if (res && ci->top < L->top + n)
112 ci->top = L->top + n; /* adjust frame top */
113 lua_unlock(L);
114 return res;
115}
116
117
118LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
119 int i;
120 if (from == to) return;
121 lua_lock(to);
122 api_checknelems(from, n);
123 api_check(from, G(from) == G(to), "moving among independent states");
124 api_check(from, to->ci->top - to->top >= n, "stack overflow");
125 from->top -= n;
126 for (i = 0; i < n; i++) {
127 setobj2s(to, to->top, from->top + i);
128 to->top++; /* stack already checked by previous 'api_check' */
129 }
130 lua_unlock(to);
131}
132
133
134LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
135 lua_CFunction old;
136 lua_lock(L);
137 old = G(L)->panic;
138 G(L)->panic = panicf;
139 lua_unlock(L);
140 return old;
141}
142
143
144LUA_API const lua_Number *lua_version (lua_State *L) {
145 static const lua_Number version = LUA_VERSION_NUM;
146 if (L == NULL) return &version;
147 else return G(L)->version;
148}
149
150
151
152/*
153** basic stack manipulation
154*/
155
156
157/*
158** convert an acceptable stack index into an absolute index
159*/
160LUA_API int lua_absindex (lua_State *L, int idx) {
161 return (idx > 0 || ispseudo(idx))
162 ? idx
163 : cast_int(L->top - L->ci->func) + idx;
164}
165
166
167LUA_API int lua_gettop (lua_State *L) {
168 return cast_int(L->top - (L->ci->func + 1));
169}
170
171
172LUA_API void lua_settop (lua_State *L, int idx) {
173 StkId func = L->ci->func;
174 lua_lock(L);
175 if (idx >= 0) {
176 api_check(L, idx <= L->stack_last - (func + 1), "new top too large");
177 while (L->top < (func + 1) + idx)
178 setnilvalue(L->top++);
179 L->top = (func + 1) + idx;
180 }
181 else {
182 api_check(L, -(idx+1) <= (L->top - (func + 1)), "invalid new top");
183 L->top += idx+1; /* 'subtract' index (index is negative) */
184 }
185 lua_unlock(L);
186}
187
188
189/*
190** Reverse the stack segment from 'from' to 'to'
191** (auxiliary to 'lua_rotate')
192*/
193static void reverse (lua_State *L, StkId from, StkId to) {
194 for (; from < to; from++, to--) {
195 TValue temp;
196 setobj(L, &temp, from);
197 setobjs2s(L, from, to);
198 setobj2s(L, to, &temp);
199 }
200}
201
202
203/*
204** Let x = AB, where A is a prefix of length 'n'. Then,
205** rotate x n == BA. But BA == (A^r . B^r)^r.
206*/
207LUA_API void lua_rotate (lua_State *L, int idx, int n) {
208 StkId p, t, m;
209 lua_lock(L);
210 t = L->top - 1; /* end of stack segment being rotated */
211 p = index2addr(L, idx); /* start of segment */
212 api_checkstackindex(L, idx, p);
213 api_check(L, (n >= 0 ? n : -n) <= (t - p + 1), "invalid 'n'");
214 m = (n >= 0 ? t - n : p - n - 1); /* end of prefix */
215 reverse(L, p, m); /* reverse the prefix with length 'n' */
216 reverse(L, m + 1, t); /* reverse the suffix */
217 reverse(L, p, t); /* reverse the entire segment */
218 lua_unlock(L);
219}
220
221
222LUA_API void lua_copy (lua_State *L, int fromidx, int toidx) {
223 TValue *fr, *to;
224 lua_lock(L);
225 fr = index2addr(L, fromidx);
226 to = index2addr(L, toidx);
227 api_checkvalidindex(L, to);
228 setobj(L, to, fr);
229 if (isupvalue(toidx)) /* function upvalue? */
230 luaC_barrier(L, clCvalue(L->ci->func), fr);
231 /* LUA_REGISTRYINDEX does not need gc barrier
232 (collector revisits it before finishing collection) */
233 lua_unlock(L);
234}
235
236
237LUA_API void lua_pushvalue (lua_State *L, int idx) {
238 lua_lock(L);
239 setobj2s(L, L->top, index2addr(L, idx));
240 api_incr_top(L);
241 lua_unlock(L);
242}
243
244
245
246/*
247** access functions (stack -> C)
248*/
249
250
251LUA_API int lua_type (lua_State *L, int idx) {
252 StkId o = index2addr(L, idx);
253 return (isvalid(o) ? ttnov(o) : LUA_TNONE);
254}
255
256
257LUA_API const char *lua_typename (lua_State *L, int t) {
258 UNUSED(L);
259 api_check(L, LUA_TNONE <= t && t < LUA_NUMTAGS, "invalid tag");
260 return ttypename(t);
261}
262
263
264LUA_API int lua_iscfunction (lua_State *L, int idx) {
265 StkId o = index2addr(L, idx);
266 return (ttislcf(o) || (ttisCclosure(o)));
267}
268
269
270LUA_API int lua_isinteger (lua_State *L, int idx) {
271 StkId o = index2addr(L, idx);
272 return ttisinteger(o);
273}
274
275
276LUA_API int lua_isnumber (lua_State *L, int idx) {
277 lua_Number n;
278 const TValue *o = index2addr(L, idx);
279 return tonumber(o, &n);
280}
281
282
283LUA_API int lua_isstring (lua_State *L, int idx) {
284 const TValue *o = index2addr(L, idx);
285 return (ttisstring(o) || cvt2str(o));
286}
287
288
289LUA_API int lua_isuserdata (lua_State *L, int idx) {
290 const TValue *o = index2addr(L, idx);
291 return (ttisfulluserdata(o) || ttislightuserdata(o));
292}
293
294
295LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
296 StkId o1 = index2addr(L, index1);
297 StkId o2 = index2addr(L, index2);
298 return (isvalid(o1) && isvalid(o2)) ? luaV_rawequalobj(o1, o2) : 0;
299}
300
301
302LUA_API void lua_arith (lua_State *L, int op) {
303 lua_lock(L);
304 if (op != LUA_OPUNM && op != LUA_OPBNOT)
305 api_checknelems(L, 2); /* all other operations expect two operands */
306 else { /* for unary operations, add fake 2nd operand */
307 api_checknelems(L, 1);
308 setobjs2s(L, L->top, L->top - 1);
309 api_incr_top(L);
310 }
311 /* first operand at top - 2, second at top - 1; result go to top - 2 */
312 luaO_arith(L, op, L->top - 2, L->top - 1, L->top - 2);
313 L->top--; /* remove second operand */
314 lua_unlock(L);
315}
316
317
318LUA_API int lua_compare (lua_State *L, int index1, int index2, int op) {
319 StkId o1, o2;
320 int i = 0;
321 lua_lock(L); /* may call tag method */
322 o1 = index2addr(L, index1);
323 o2 = index2addr(L, index2);
324 if (isvalid(o1) && isvalid(o2)) {
325 switch (op) {
326 case LUA_OPEQ: i = luaV_equalobj(L, o1, o2); break;
327 case LUA_OPLT: i = luaV_lessthan(L, o1, o2); break;
328 case LUA_OPLE: i = luaV_lessequal(L, o1, o2); break;
329 default: api_check(L, 0, "invalid option");
330 }
331 }
332 lua_unlock(L);
333 return i;
334}
335
336
337LUA_API size_t lua_stringtonumber (lua_State *L, const char *s) {
338 size_t sz = luaO_str2num(s, L->top);
339 if (sz != 0)
340 api_incr_top(L);
341 return sz;
342}
343
344
345LUA_API lua_Number lua_tonumberx (lua_State *L, int idx, int *pisnum) {
346 lua_Number n;
347 const TValue *o = index2addr(L, idx);
348 int isnum = tonumber(o, &n);
349 if (!isnum)
350 n = 0; /* call to 'tonumber' may change 'n' even if it fails */
351 if (pisnum) *pisnum = isnum;
352 return n;
353}
354
355
356LUA_API lua_Integer lua_tointegerx (lua_State *L, int idx, int *pisnum) {
357 lua_Integer res;
358 const TValue *o = index2addr(L, idx);
359 int isnum = tointeger(o, &res);
360 if (!isnum)
361 res = 0; /* call to 'tointeger' may change 'n' even if it fails */
362 if (pisnum) *pisnum = isnum;
363 return res;
364}
365
366
367LUA_API int lua_toboolean (lua_State *L, int idx) {
368 const TValue *o = index2addr(L, idx);
369 return !l_isfalse(o);
370}
371
372
373LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
374 StkId o = index2addr(L, idx);
375 if (!ttisstring(o)) {
376 if (!cvt2str(o)) { /* not convertible? */
377 if (len != NULL) *len = 0;
378 return NULL;
379 }
380 lua_lock(L); /* 'luaO_tostring' may create a new string */
381 luaO_tostring(L, o);
382 luaC_checkGC(L);
383 o = index2addr(L, idx); /* previous call may reallocate the stack */
384 lua_unlock(L);
385 }
386 if (len != NULL)
387 *len = vslen(o);
388 return svalue(o);
389}
390
391
392LUA_API size_t lua_rawlen (lua_State *L, int idx) {
393 StkId o = index2addr(L, idx);
394 switch (ttype(o)) {
395 case LUA_TSHRSTR: return tsvalue(o)->shrlen;
396 case LUA_TLNGSTR: return tsvalue(o)->u.lnglen;
397 case LUA_TUSERDATA: return uvalue(o)->len;
398 case LUA_TTABLE: return luaH_getn(hvalue(o));
399 default: return 0;
400 }
401}
402
403
404LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
405 StkId o = index2addr(L, idx);
406 if (ttislcf(o)) return fvalue(o);
407 else if (ttisCclosure(o))
408 return clCvalue(o)->f;
409 else return NULL; /* not a C function */
410}
411
412
413LUA_API void *lua_touserdata (lua_State *L, int idx) {
414 StkId o = index2addr(L, idx);
415 switch (ttnov(o)) {
416 case LUA_TUSERDATA: return getudatamem(uvalue(o));
417 case LUA_TLIGHTUSERDATA: return pvalue(o);
418 default: return NULL;
419 }
420}
421
422
423LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
424 StkId o = index2addr(L, idx);
425 return (!ttisthread(o)) ? NULL : thvalue(o);
426}
427
428
429LUA_API const void *lua_topointer (lua_State *L, int idx) {
430 StkId o = index2addr(L, idx);
431 switch (ttype(o)) {
432 case LUA_TTABLE: return hvalue(o);
433 case LUA_TLCL: return clLvalue(o);
434 case LUA_TCCL: return clCvalue(o);
435 case LUA_TLCF: return cast(void *, cast(size_t, fvalue(o)));
436 case LUA_TTHREAD: return thvalue(o);
437 case LUA_TUSERDATA: return getudatamem(uvalue(o));
438 case LUA_TLIGHTUSERDATA: return pvalue(o);
439 default: return NULL;
440 }
441}
442
443
444
445/*
446** push functions (C -> stack)
447*/
448
449
450LUA_API void lua_pushnil (lua_State *L) {
451 lua_lock(L);
452 setnilvalue(L->top);
453 api_incr_top(L);
454 lua_unlock(L);
455}
456
457
458LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
459 lua_lock(L);
460 setfltvalue(L->top, n);
461 api_incr_top(L);
462 lua_unlock(L);
463}
464
465
466LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
467 lua_lock(L);
468 setivalue(L->top, n);
469 api_incr_top(L);
470 lua_unlock(L);
471}
472
473
474/*
475** Pushes on the stack a string with given length. Avoid using 's' when
476** 'len' == 0 (as 's' can be NULL in that case), due to later use of
477** 'memcmp' and 'memcpy'.
478*/
479LUA_API const char *lua_pushlstring (lua_State *L, const char *s, size_t len) {
480 TString *ts;
481 lua_lock(L);
482 ts = (len == 0) ? luaS_new(L, "") : luaS_newlstr(L, s, len);
483 setsvalue2s(L, L->top, ts);
484 api_incr_top(L);
485 luaC_checkGC(L);
486 lua_unlock(L);
487 return getstr(ts);
488}
489
490
491LUA_API const char *lua_pushstring (lua_State *L, const char *s) {
492 lua_lock(L);
493 if (s == NULL)
494 setnilvalue(L->top);
495 else {
496 TString *ts;
497 ts = luaS_new(L, s);
498 setsvalue2s(L, L->top, ts);
499 s = getstr(ts); /* internal copy's address */
500 }
501 api_incr_top(L);
502 luaC_checkGC(L);
503 lua_unlock(L);
504 return s;
505}
506
507
508LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
509 va_list argp) {
510 const char *ret;
511 lua_lock(L);
512 ret = luaO_pushvfstring(L, fmt, argp);
513 luaC_checkGC(L);
514 lua_unlock(L);
515 return ret;
516}
517
518
519LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
520 const char *ret;
521 va_list argp;
522 lua_lock(L);
523 va_start(argp, fmt);
524 ret = luaO_pushvfstring(L, fmt, argp);
525 va_end(argp);
526 luaC_checkGC(L);
527 lua_unlock(L);
528 return ret;
529}
530
531
532LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
533 lua_lock(L);
534 if (n == 0) {
535 setfvalue(L->top, fn);
536 api_incr_top(L);
537 }
538 else {
539 CClosure *cl;
540 api_checknelems(L, n);
541 api_check(L, n <= MAXUPVAL, "upvalue index too large");
542 cl = luaF_newCclosure(L, n);
543 cl->f = fn;
544 L->top -= n;
545 while (n--) {
546 setobj2n(L, &cl->upvalue[n], L->top + n);
547 /* does not need barrier because closure is white */
548 }
549 setclCvalue(L, L->top, cl);
550 api_incr_top(L);
551 luaC_checkGC(L);
552 }
553 lua_unlock(L);
554}
555
556
557LUA_API void lua_pushboolean (lua_State *L, int b) {
558 lua_lock(L);
559 setbvalue(L->top, (b != 0)); /* ensure that true is 1 */
560 api_incr_top(L);
561 lua_unlock(L);
562}
563
564
565LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
566 lua_lock(L);
567 setpvalue(L->top, p);
568 api_incr_top(L);
569 lua_unlock(L);
570}
571
572
573LUA_API int lua_pushthread (lua_State *L) {
574 lua_lock(L);
575 setthvalue(L, L->top, L);
576 api_incr_top(L);
577 lua_unlock(L);
578 return (G(L)->mainthread == L);
579}
580
581
582
583/*
584** get functions (Lua -> stack)
585*/
586
587
588static int auxgetstr (lua_State *L, const TValue *t, const char *k) {
589 const TValue *slot;
590 TString *str = luaS_new(L, k);
591 if (luaV_fastget(L, t, str, slot, luaH_getstr)) {
592 setobj2s(L, L->top, slot);
593 api_incr_top(L);
594 }
595 else {
596 setsvalue2s(L, L->top, str);
597 api_incr_top(L);
598 luaV_finishget(L, t, L->top - 1, L->top - 1, slot);
599 }
600 lua_unlock(L);
601 return ttnov(L->top - 1);
602}
603
604
605LUA_API int lua_getglobal (lua_State *L, const char *name) {
606 Table *reg = hvalue(&G(L)->l_registry);
607 lua_lock(L);
608 return auxgetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
609}
610
611
612LUA_API int lua_gettable (lua_State *L, int idx) {
613 StkId t;
614 lua_lock(L);
615 t = index2addr(L, idx);
616 luaV_gettable(L, t, L->top - 1, L->top - 1);
617 lua_unlock(L);
618 return ttnov(L->top - 1);
619}
620
621
622LUA_API int lua_getfield (lua_State *L, int idx, const char *k) {
623 lua_lock(L);
624 return auxgetstr(L, index2addr(L, idx), k);
625}
626
627
628LUA_API int lua_geti (lua_State *L, int idx, lua_Integer n) {
629 StkId t;
630 const TValue *slot;
631 lua_lock(L);
632 t = index2addr(L, idx);
633 if (luaV_fastget(L, t, n, slot, luaH_getint)) {
634 setobj2s(L, L->top, slot);
635 api_incr_top(L);
636 }
637 else {
638 setivalue(L->top, n);
639 api_incr_top(L);
640 luaV_finishget(L, t, L->top - 1, L->top - 1, slot);
641 }
642 lua_unlock(L);
643 return ttnov(L->top - 1);
644}
645
646
647LUA_API int lua_rawget (lua_State *L, int idx) {
648 StkId t;
649 lua_lock(L);
650 t = index2addr(L, idx);
651 api_check(L, ttistable(t), "table expected");
652 setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
653 lua_unlock(L);
654 return ttnov(L->top - 1);
655}
656
657
658LUA_API int lua_rawgeti (lua_State *L, int idx, lua_Integer n) {
659 StkId t;
660 lua_lock(L);
661 t = index2addr(L, idx);
662 api_check(L, ttistable(t), "table expected");
663 setobj2s(L, L->top, luaH_getint(hvalue(t), n));
664 api_incr_top(L);
665 lua_unlock(L);
666 return ttnov(L->top - 1);
667}
668
669
670LUA_API int lua_rawgetp (lua_State *L, int idx, const void *p) {
671 StkId t;
672 TValue k;
673 lua_lock(L);
674 t = index2addr(L, idx);
675 api_check(L, ttistable(t), "table expected");
676 setpvalue(&k, cast(void *, p));
677 setobj2s(L, L->top, luaH_get(hvalue(t), &k));
678 api_incr_top(L);
679 lua_unlock(L);
680 return ttnov(L->top - 1);
681}
682
683
684LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
685 Table *t;
686 lua_lock(L);
687 t = luaH_new(L);
688 sethvalue(L, L->top, t);
689 api_incr_top(L);
690 if (narray > 0 || nrec > 0)
691 luaH_resize(L, t, narray, nrec);
692 luaC_checkGC(L);
693 lua_unlock(L);
694}
695
696
697LUA_API int lua_getmetatable (lua_State *L, int objindex) {
698 const TValue *obj;
699 Table *mt;
700 int res = 0;
701 lua_lock(L);
702 obj = index2addr(L, objindex);
703 switch (ttnov(obj)) {
704 case LUA_TTABLE:
705 mt = hvalue(obj)->metatable;
706 break;
707 case LUA_TUSERDATA:
708 mt = uvalue(obj)->metatable;
709 break;
710 default:
711 mt = G(L)->mt[ttnov(obj)];
712 break;
713 }
714 if (mt != NULL) {
715 sethvalue(L, L->top, mt);
716 api_incr_top(L);
717 res = 1;
718 }
719 lua_unlock(L);
720 return res;
721}
722
723
724LUA_API int lua_getuservalue (lua_State *L, int idx) {
725 StkId o;
726 lua_lock(L);
727 o = index2addr(L, idx);
728 api_check(L, ttisfulluserdata(o), "full userdata expected");
729 getuservalue(L, uvalue(o), L->top);
730 api_incr_top(L);
731 lua_unlock(L);
732 return ttnov(L->top - 1);
733}
734
735
736/*
737** set functions (stack -> Lua)
738*/
739
740/*
741** t[k] = value at the top of the stack (where 'k' is a string)
742*/
743static void auxsetstr (lua_State *L, const TValue *t, const char *k) {
744 const TValue *slot;
745 TString *str = luaS_new(L, k);
746 api_checknelems(L, 1);
747 if (luaV_fastset(L, t, str, slot, luaH_getstr, L->top - 1))
748 L->top--; /* pop value */
749 else {
750 setsvalue2s(L, L->top, str); /* push 'str' (to make it a TValue) */
751 api_incr_top(L);
752 luaV_finishset(L, t, L->top - 1, L->top - 2, slot);
753 L->top -= 2; /* pop value and key */
754 }
755 lua_unlock(L); /* lock done by caller */
756}
757
758
759LUA_API void lua_setglobal (lua_State *L, const char *name) {
760 Table *reg = hvalue(&G(L)->l_registry);
761 lua_lock(L); /* unlock done in 'auxsetstr' */
762 auxsetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
763}
764
765
766LUA_API void lua_settable (lua_State *L, int idx) {
767 StkId t;
768 lua_lock(L);
769 api_checknelems(L, 2);
770 t = index2addr(L, idx);
771 luaV_settable(L, t, L->top - 2, L->top - 1);
772 L->top -= 2; /* pop index and value */
773 lua_unlock(L);
774}
775
776
777LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
778 lua_lock(L); /* unlock done in 'auxsetstr' */
779 auxsetstr(L, index2addr(L, idx), k);
780}
781
782
783LUA_API void lua_seti (lua_State *L, int idx, lua_Integer n) {
784 StkId t;
785 const TValue *slot;
786 lua_lock(L);
787 api_checknelems(L, 1);
788 t = index2addr(L, idx);
789 if (luaV_fastset(L, t, n, slot, luaH_getint, L->top - 1))
790 L->top--; /* pop value */
791 else {
792 setivalue(L->top, n);
793 api_incr_top(L);
794 luaV_finishset(L, t, L->top - 1, L->top - 2, slot);
795 L->top -= 2; /* pop value and key */
796 }
797 lua_unlock(L);
798}
799
800
801LUA_API void lua_rawset (lua_State *L, int idx) {
802 StkId o;
803 TValue *slot;
804 lua_lock(L);
805 api_checknelems(L, 2);
806 o = index2addr(L, idx);
807 api_check(L, ttistable(o), "table expected");
808 slot = luaH_set(L, hvalue(o), L->top - 2);
809 setobj2t(L, slot, L->top - 1);
810 invalidateTMcache(hvalue(o));
811 luaC_barrierback(L, hvalue(o), L->top-1);
812 L->top -= 2;
813 lua_unlock(L);
814}
815
816
817LUA_API void lua_rawseti (lua_State *L, int idx, lua_Integer n) {
818 StkId o;
819 lua_lock(L);
820 api_checknelems(L, 1);
821 o = index2addr(L, idx);
822 api_check(L, ttistable(o), "table expected");
823 luaH_setint(L, hvalue(o), n, L->top - 1);
824 luaC_barrierback(L, hvalue(o), L->top-1);
825 L->top--;
826 lua_unlock(L);
827}
828
829
830LUA_API void lua_rawsetp (lua_State *L, int idx, const void *p) {
831 StkId o;
832 TValue k, *slot;
833 lua_lock(L);
834 api_checknelems(L, 1);
835 o = index2addr(L, idx);
836 api_check(L, ttistable(o), "table expected");
837 setpvalue(&k, cast(void *, p));
838 slot = luaH_set(L, hvalue(o), &k);
839 setobj2t(L, slot, L->top - 1);
840 luaC_barrierback(L, hvalue(o), L->top - 1);
841 L->top--;
842 lua_unlock(L);
843}
844
845
846LUA_API int lua_setmetatable (lua_State *L, int objindex) {
847 TValue *obj;
848 Table *mt;
849 lua_lock(L);
850 api_checknelems(L, 1);
851 obj = index2addr(L, objindex);
852 if (ttisnil(L->top - 1))
853 mt = NULL;
854 else {
855 api_check(L, ttistable(L->top - 1), "table expected");
856 mt = hvalue(L->top - 1);
857 }
858 switch (ttnov(obj)) {
859 case LUA_TTABLE: {
860 hvalue(obj)->metatable = mt;
861 if (mt) {
862 luaC_objbarrier(L, gcvalue(obj), mt);
863 luaC_checkfinalizer(L, gcvalue(obj), mt);
864 }
865 break;
866 }
867 case LUA_TUSERDATA: {
868 uvalue(obj)->metatable = mt;
869 if (mt) {
870 luaC_objbarrier(L, uvalue(obj), mt);
871 luaC_checkfinalizer(L, gcvalue(obj), mt);
872 }
873 break;
874 }
875 default: {
876 G(L)->mt[ttnov(obj)] = mt;
877 break;
878 }
879 }
880 L->top--;
881 lua_unlock(L);
882 return 1;
883}
884
885
886LUA_API void lua_setuservalue (lua_State *L, int idx) {
887 StkId o;
888 lua_lock(L);
889 api_checknelems(L, 1);
890 o = index2addr(L, idx);
891 api_check(L, ttisfulluserdata(o), "full userdata expected");
892 setuservalue(L, uvalue(o), L->top - 1);
893 luaC_barrier(L, gcvalue(o), L->top - 1);
894 L->top--;
895 lua_unlock(L);
896}
897
898
899/*
900** 'load' and 'call' functions (run Lua code)
901*/
902
903
904#define checkresults(L,na,nr) \
905 api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)), \
906 "results from function overflow current stack size")
907
908
909LUA_API void lua_callk (lua_State *L, int nargs, int nresults,
910 lua_KContext ctx, lua_KFunction k) {
911 StkId func;
912 lua_lock(L);
913 api_check(L, k == NULL || !isLua(L->ci),
914 "cannot use continuations inside hooks");
915 api_checknelems(L, nargs+1);
916 api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
917 checkresults(L, nargs, nresults);
918 func = L->top - (nargs+1);
919 if (k != NULL && L->nny == 0) { /* need to prepare continuation? */
920 L->ci->u.c.k = k; /* save continuation */
921 L->ci->u.c.ctx = ctx; /* save context */
922 luaD_call(L, func, nresults); /* do the call */
923 }
924 else /* no continuation or no yieldable */
925 luaD_callnoyield(L, func, nresults); /* just do the call */
926 adjustresults(L, nresults);
927 lua_unlock(L);
928}
929
930
931
932/*
933** Execute a protected call.
934*/
935struct CallS { /* data to 'f_call' */
936 StkId func;
937 int nresults;
938};
939
940
941static void f_call (lua_State *L, void *ud) {
942 struct CallS *c = cast(struct CallS *, ud);
943 luaD_callnoyield(L, c->func, c->nresults);
944}
945
946
947
948LUA_API int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc,
949 lua_KContext ctx, lua_KFunction k) {
950 struct CallS c;
951 int status;
952 ptrdiff_t func;
953 lua_lock(L);
954 api_check(L, k == NULL || !isLua(L->ci),
955 "cannot use continuations inside hooks");
956 api_checknelems(L, nargs+1);
957 api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
958 checkresults(L, nargs, nresults);
959 if (errfunc == 0)
960 func = 0;
961 else {
962 StkId o = index2addr(L, errfunc);
963 api_checkstackindex(L, errfunc, o);
964 func = savestack(L, o);
965 }
966 c.func = L->top - (nargs+1); /* function to be called */
967 if (k == NULL || L->nny > 0) { /* no continuation or no yieldable? */
968 c.nresults = nresults; /* do a 'conventional' protected call */
969 status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
970 }
971 else { /* prepare continuation (call is already protected by 'resume') */
972 CallInfo *ci = L->ci;
973 ci->u.c.k = k; /* save continuation */
974 ci->u.c.ctx = ctx; /* save context */
975 /* save information for error recovery */
976 ci->extra = savestack(L, c.func);
977 ci->u.c.old_errfunc = L->errfunc;
978 L->errfunc = func;
979 setoah(ci->callstatus, L->allowhook); /* save value of 'allowhook' */
980 ci->callstatus |= CIST_YPCALL; /* function can do error recovery */
981 luaD_call(L, c.func, nresults); /* do the call */
982 ci->callstatus &= ~CIST_YPCALL;
983 L->errfunc = ci->u.c.old_errfunc;
984 status = LUA_OK; /* if it is here, there were no errors */
985 }
986 adjustresults(L, nresults);
987 lua_unlock(L);
988 return status;
989}
990
991
992LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
993 const char *chunkname, const char *mode) {
994 ZIO z;
995 int status;
996 lua_lock(L);
997 if (!chunkname) chunkname = "?";
998 luaZ_init(L, &z, reader, data);
999 status = luaD_protectedparser(L, &z, chunkname, mode);
1000 if (status == LUA_OK) { /* no errors? */
1001 LClosure *f = clLvalue(L->top - 1); /* get newly created function */
1002 if (f->nupvalues >= 1) { /* does it have an upvalue? */
1003 /* get global table from registry */
1004 Table *reg = hvalue(&G(L)->l_registry);
1005 const TValue *gt = luaH_getint(reg, LUA_RIDX_GLOBALS);
1006 /* set global table as 1st upvalue of 'f' (may be LUA_ENV) */
1007 setobj(L, f->upvals[0]->v, gt);
1008 luaC_upvalbarrier(L, f->upvals[0]);
1009 }
1010 }
1011 lua_unlock(L);
1012 return status;
1013}
1014
1015
1016LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data, int strip) {
1017 int status;
1018 TValue *o;
1019 lua_lock(L);
1020 api_checknelems(L, 1);
1021 o = L->top - 1;
1022 if (isLfunction(o))
1023 status = luaU_dump(L, getproto(o), writer, data, strip);
1024 else
1025 status = 1;
1026 lua_unlock(L);
1027 return status;
1028}
1029
1030
1031LUA_API int lua_status (lua_State *L) {
1032 return L->status;
1033}
1034
1035
1036/*
1037** Garbage-collection function
1038*/
1039
1040LUA_API int lua_gc (lua_State *L, int what, int data) {
1041 int res = 0;
1042 global_State *g;
1043 lua_lock(L);
1044 g = G(L);
1045 switch (what) {
1046 case LUA_GCSTOP: {
1047 g->gcrunning = 0;
1048 break;
1049 }
1050 case LUA_GCRESTART: {
1051 luaE_setdebt(g, 0);
1052 g->gcrunning = 1;
1053 break;
1054 }
1055 case LUA_GCCOLLECT: {
1056 luaC_fullgc(L, 0);
1057 break;
1058 }
1059 case LUA_GCCOUNT: {
1060 /* GC values are expressed in Kbytes: #bytes/2^10 */
1061 res = cast_int(gettotalbytes(g) >> 10);
1062 break;
1063 }
1064 case LUA_GCCOUNTB: {
1065 res = cast_int(gettotalbytes(g) & 0x3ff);
1066 break;
1067 }
1068 case LUA_GCSTEP: {
1069 l_mem debt = 1; /* =1 to signal that it did an actual step */
1070 lu_byte oldrunning = g->gcrunning;
1071 g->gcrunning = 1; /* allow GC to run */
1072 if (data == 0) {
1073 luaE_setdebt(g, -GCSTEPSIZE); /* to do a "small" step */
1074 luaC_step(L);
1075 }
1076 else { /* add 'data' to total debt */
1077 debt = cast(l_mem, data) * 1024 + g->GCdebt;
1078 luaE_setdebt(g, debt);
1079 luaC_checkGC(L);
1080 }
1081 g->gcrunning = oldrunning; /* restore previous state */
1082 if (debt > 0 && g->gcstate == GCSpause) /* end of cycle? */
1083 res = 1; /* signal it */
1084 break;
1085 }
1086 case LUA_GCSETPAUSE: {
1087 res = g->gcpause;
1088 g->gcpause = data;
1089 break;
1090 }
1091 case LUA_GCSETSTEPMUL: {
1092 res = g->gcstepmul;
1093 if (data < 40) data = 40; /* avoid ridiculous low values (and 0) */
1094 g->gcstepmul = data;
1095 break;
1096 }
1097 case LUA_GCISRUNNING: {
1098 res = g->gcrunning;
1099 break;
1100 }
1101 default: res = -1; /* invalid option */
1102 }
1103 lua_unlock(L);
1104 return res;
1105}
1106
1107
1108
1109/*
1110** miscellaneous functions
1111*/
1112
1113
1114LUA_API int lua_error (lua_State *L) {
1115 lua_lock(L);
1116 api_checknelems(L, 1);
1117 luaG_errormsg(L);
1118 /* code unreachable; will unlock when control actually leaves the kernel */
1119 return 0; /* to avoid warnings */
1120}
1121
1122
1123LUA_API int lua_next (lua_State *L, int idx) {
1124 StkId t;
1125 int more;
1126 lua_lock(L);
1127 t = index2addr(L, idx);
1128 api_check(L, ttistable(t), "table expected");
1129 more = luaH_next(L, hvalue(t), L->top - 1);
1130 if (more) {
1131 api_incr_top(L);
1132 }
1133 else /* no more elements */
1134 L->top -= 1; /* remove key */
1135 lua_unlock(L);
1136 return more;
1137}
1138
1139
1140LUA_API void lua_concat (lua_State *L, int n) {
1141 lua_lock(L);
1142 api_checknelems(L, n);
1143 if (n >= 2) {
1144 luaV_concat(L, n);
1145 }
1146 else if (n == 0) { /* push empty string */
1147 setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
1148 api_incr_top(L);
1149 }
1150 /* else n == 1; nothing to do */
1151 luaC_checkGC(L);
1152 lua_unlock(L);
1153}
1154
1155
1156LUA_API void lua_len (lua_State *L, int idx) {
1157 StkId t;
1158 lua_lock(L);
1159 t = index2addr(L, idx);
1160 luaV_objlen(L, L->top, t);
1161 api_incr_top(L);
1162 lua_unlock(L);
1163}
1164
1165
1166LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
1167 lua_Alloc f;
1168 lua_lock(L);
1169 if (ud) *ud = G(L)->ud;
1170 f = G(L)->frealloc;
1171 lua_unlock(L);
1172 return f;
1173}
1174
1175
1176LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
1177 lua_lock(L);
1178 G(L)->ud = ud;
1179 G(L)->frealloc = f;
1180 lua_unlock(L);
1181}
1182
1183
1184LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
1185 Udata *u;
1186 lua_lock(L);
1187 u = luaS_newudata(L, size);
1188 setuvalue(L, L->top, u);
1189 api_incr_top(L);
1190 luaC_checkGC(L);
1191 lua_unlock(L);
1192 return getudatamem(u);
1193}
1194
1195
1196
1197static const char *aux_upvalue (StkId fi, int n, TValue **val,
1198 CClosure **owner, UpVal **uv) {
1199 switch (ttype(fi)) {
1200 case LUA_TCCL: { /* C closure */
1201 CClosure *f = clCvalue(fi);
1202 if (!(1 <= n && n <= f->nupvalues)) return NULL;
1203 *val = &f->upvalue[n-1];
1204 if (owner) *owner = f;
1205 return "";
1206 }
1207 case LUA_TLCL: { /* Lua closure */
1208 LClosure *f = clLvalue(fi);
1209 TString *name;
1210 Proto *p = f->p;
1211 if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
1212 *val = f->upvals[n-1]->v;
1213 if (uv) *uv = f->upvals[n - 1];
1214 name = p->upvalues[n-1].name;
1215 return (name == NULL) ? "(*no name)" : getstr(name);
1216 }
1217 default: return NULL; /* not a closure */
1218 }
1219}
1220
1221
1222LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
1223 const char *name;
1224 TValue *val = NULL; /* to avoid warnings */
1225 lua_lock(L);
1226 name = aux_upvalue(index2addr(L, funcindex), n, &val, NULL, NULL);
1227 if (name) {
1228 setobj2s(L, L->top, val);
1229 api_incr_top(L);
1230 }
1231 lua_unlock(L);
1232 return name;
1233}
1234
1235
1236LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
1237 const char *name;
1238 TValue *val = NULL; /* to avoid warnings */
1239 CClosure *owner = NULL;
1240 UpVal *uv = NULL;
1241 StkId fi;
1242 lua_lock(L);
1243 fi = index2addr(L, funcindex);
1244 api_checknelems(L, 1);
1245 name = aux_upvalue(fi, n, &val, &owner, &uv);
1246 if (name) {
1247 L->top--;
1248 setobj(L, val, L->top);
1249 if (owner) { luaC_barrier(L, owner, L->top); }
1250 else if (uv) { luaC_upvalbarrier(L, uv); }
1251 }
1252 lua_unlock(L);
1253 return name;
1254}
1255
1256
1257static UpVal **getupvalref (lua_State *L, int fidx, int n) {
1258 LClosure *f;
1259 StkId fi = index2addr(L, fidx);
1260 api_check(L, ttisLclosure(fi), "Lua function expected");
1261 f = clLvalue(fi);
1262 api_check(L, (1 <= n && n <= f->p->sizeupvalues), "invalid upvalue index");
1263 return &f->upvals[n - 1]; /* get its upvalue pointer */
1264}
1265
1266
1267LUA_API void *lua_upvalueid (lua_State *L, int fidx, int n) {
1268 StkId fi = index2addr(L, fidx);
1269 switch (ttype(fi)) {
1270 case LUA_TLCL: { /* lua closure */
1271 return *getupvalref(L, fidx, n);
1272 }
1273 case LUA_TCCL: { /* C closure */
1274 CClosure *f = clCvalue(fi);
1275 api_check(L, 1 <= n && n <= f->nupvalues, "invalid upvalue index");
1276 return &f->upvalue[n - 1];
1277 }
1278 default: {
1279 api_check(L, 0, "closure expected");
1280 return NULL;
1281 }
1282 }
1283}
1284
1285
1286LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
1287 int fidx2, int n2) {
1288 UpVal **up1 = getupvalref(L, fidx1, n1);
1289 UpVal **up2 = getupvalref(L, fidx2, n2);
1290 if (*up1 == *up2)
1291 return;
1292 luaC_upvdeccount(L, *up1);
1293 *up1 = *up2;
1294 (*up1)->refcount++;
1295 if (upisopen(*up1)) (*up1)->u.open.touched = 1;
1296 luaC_upvalbarrier(L, *up1);
1297}
1298
1299
1300