1 /*
2 ** $Id: lapi.c,v 2.257 2015/11/02 18:48:07 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
34 const 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
60 static TValue *index2addr (lua_State *L, int idx) {
|
(1) Event deref_parm: |
Directly dereferencing parameter "L". |
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 */
91 static void growstack (lua_State *L, void *ud) {
92 int size = *(int *)ud;
93 luaD_growstack(L, size);
94 }
95
96
97 LUA_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
118 LUA_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
134 LUA_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
144 LUA_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 */
160 LUA_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
167 LUA_API int lua_gettop (lua_State *L) {
168 return cast_int(L->top - (L->ci->func + 1));
169 }
170
171
172 LUA_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 */
193 static 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 */
207 LUA_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
222 LUA_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
237 LUA_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
251 LUA_API int lua_type (lua_State *L, int idx) {
|
(1) Event deref_parm_in_call: |
Function "index2addr" dereferences "L". [details] |
252 StkId o = index2addr(L, idx);
253 return (isvalid(o) ? ttnov(o) : LUA_TNONE);
254 }
255
256
257 LUA_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
264 LUA_API int lua_iscfunction (lua_State *L, int idx) {
265 StkId o = index2addr(L, idx);
266 return (ttislcf(o) || (ttisCclosure(o)));
267 }
268
269
270 LUA_API int lua_isinteger (lua_State *L, int idx) {
271 StkId o = index2addr(L, idx);
272 return ttisinteger(o);
273 }
274
275
276 LUA_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
283 LUA_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
289 LUA_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
295 LUA_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
302 LUA_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
318 LUA_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
337 LUA_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
345 LUA_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
356 LUA_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
367 LUA_API int lua_toboolean (lua_State *L, int idx) {
368 const TValue *o = index2addr(L, idx);
369 return !l_isfalse(o);
370 }
371
372
373 LUA_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 luaC_checkGC(L);
382 o = index2addr(L, idx); /* previous call may reallocate the stack */
383 luaO_tostring(L, o);
384 lua_unlock(L);
385 }
386 if (len != NULL)
387 *len = vslen(o);
388 return svalue(o);
389 }
390
391
392 LUA_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
404 LUA_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
413 LUA_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
423 LUA_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
429 LUA_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
450 LUA_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
458 LUA_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
466 LUA_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 */
479 LUA_API const char *lua_pushlstring (lua_State *L, const char *s, size_t len) {
480 TString *ts;
481 lua_lock(L);
482 luaC_checkGC(L);
483 ts = (len == 0) ? luaS_new(L, "") : luaS_newlstr(L, s, len);
484 setsvalue2s(L, L->top, ts);
485 api_incr_top(L);
486 lua_unlock(L);
487 return getstr(ts);
488 }
489
490
491 LUA_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 luaC_checkGC(L);
498 ts = luaS_new(L, s);
499 setsvalue2s(L, L->top, ts);
500 s = getstr(ts); /* internal copy's address */
501 }
502 api_incr_top(L);
503 lua_unlock(L);
504 return s;
505 }
506
507
508 LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
509 va_list argp) {
510 const char *ret;
511 lua_lock(L);
512 luaC_checkGC(L);
513 ret = luaO_pushvfstring(L, fmt, argp);
514 lua_unlock(L);
515 return ret;
516 }
517
518
519 LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
520 const char *ret;
521 va_list argp;
522 lua_lock(L);
523 luaC_checkGC(L);
524 va_start(argp, fmt);
525 ret = luaO_pushvfstring(L, fmt, argp);
526 va_end(argp);
527 lua_unlock(L);
528 return ret;
529 }
530
531
532 LUA_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 }
537 else {
538 CClosure *cl;
539 api_checknelems(L, n);
540 api_check(L, n <= MAXUPVAL, "upvalue index too large");
541 luaC_checkGC(L);
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 }
551 api_incr_top(L);
552 lua_unlock(L);
553 }
554
555
556 LUA_API void lua_pushboolean (lua_State *L, int b) {
557 lua_lock(L);
558 setbvalue(L->top, (b != 0)); /* ensure that true is 1 */
559 api_incr_top(L);
560 lua_unlock(L);
561 }
562
563
564 LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
565 lua_lock(L);
566 setpvalue(L->top, p);
567 api_incr_top(L);
568 lua_unlock(L);
569 }
570
571
572 LUA_API int lua_pushthread (lua_State *L) {
573 lua_lock(L);
574 setthvalue(L, L->top, L);
575 api_incr_top(L);
576 lua_unlock(L);
577 return (G(L)->mainthread == L);
578 }
579
580
581
582 /*
583 ** get functions (Lua -> stack)
584 */
585
586
587 static int auxgetstr (lua_State *L, const TValue *t, const char *k) {
588 const TValue *aux;
589 TString *str = luaS_new(L, k);
590 if (luaV_fastget(L, t, str, aux, luaH_getstr)) {
591 setobj2s(L, L->top, aux);
592 api_incr_top(L);
593 }
594 else {
595 setsvalue2s(L, L->top, str);
596 api_incr_top(L);
597 luaV_finishget(L, t, L->top - 1, L->top - 1, aux);
598 }
599 lua_unlock(L);
600 return ttnov(L->top - 1);
601 }
602
603
604 LUA_API int lua_getglobal (lua_State *L, const char *name) {
605 Table *reg = hvalue(&G(L)->l_registry);
606 lua_lock(L);
607 return auxgetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
608 }
609
610
611 LUA_API int lua_gettable (lua_State *L, int idx) {
612 StkId t;
613 lua_lock(L);
614 t = index2addr(L, idx);
615 luaV_gettable(L, t, L->top - 1, L->top - 1);
616 lua_unlock(L);
617 return ttnov(L->top - 1);
618 }
619
620
621 LUA_API int lua_getfield (lua_State *L, int idx, const char *k) {
622 lua_lock(L);
623 return auxgetstr(L, index2addr(L, idx), k);
624 }
625
626
627 LUA_API int lua_geti (lua_State *L, int idx, lua_Integer n) {
628 StkId t;
629 const TValue *aux;
630 lua_lock(L);
631 t = index2addr(L, idx);
632 if (luaV_fastget(L, t, n, aux, luaH_getint)) {
633 setobj2s(L, L->top, aux);
634 api_incr_top(L);
635 }
636 else {
637 setivalue(L->top, n);
638 api_incr_top(L);
639 luaV_finishget(L, t, L->top - 1, L->top - 1, aux);
640 }
641 lua_unlock(L);
642 return ttnov(L->top - 1);
643 }
644
645
646 LUA_API int lua_rawget (lua_State *L, int idx) {
647 StkId t;
648 lua_lock(L);
649 t = index2addr(L, idx);
650 api_check(L, ttistable(t), "table expected");
651 setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
652 lua_unlock(L);
653 return ttnov(L->top - 1);
654 }
655
656
657 LUA_API int lua_rawgeti (lua_State *L, int idx, lua_Integer n) {
658 StkId t;
659 lua_lock(L);
660 t = index2addr(L, idx);
661 api_check(L, ttistable(t), "table expected");
662 setobj2s(L, L->top, luaH_getint(hvalue(t), n));
663 api_incr_top(L);
664 lua_unlock(L);
665 return ttnov(L->top - 1);
666 }
667
668
669 LUA_API int lua_rawgetp (lua_State *L, int idx, const void *p) {
670 StkId t;
671 TValue k;
672 lua_lock(L);
673 t = index2addr(L, idx);
674 api_check(L, ttistable(t), "table expected");
675 setpvalue(&k, cast(void *, p));
676 setobj2s(L, L->top, luaH_get(hvalue(t), &k));
677 api_incr_top(L);
678 lua_unlock(L);
679 return ttnov(L->top - 1);
680 }
681
682
683 LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
684 Table *t;
685 lua_lock(L);
686 luaC_checkGC(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 lua_unlock(L);
693 }
694
695
696 LUA_API int lua_getmetatable (lua_State *L, int objindex) {
697 const TValue *obj;
698 Table *mt;
699 int res = 0;
700 lua_lock(L);
701 obj = index2addr(L, objindex);
702 switch (ttnov(obj)) {
703 case LUA_TTABLE:
704 mt = hvalue(obj)->metatable;
705 break;
706 case LUA_TUSERDATA:
707 mt = uvalue(obj)->metatable;
708 break;
709 default:
710 mt = G(L)->mt[ttnov(obj)];
711 break;
712 }
713 if (mt != NULL) {
714 sethvalue(L, L->top, mt);
715 api_incr_top(L);
716 res = 1;
717 }
718 lua_unlock(L);
719 return res;
720 }
721
722
723 LUA_API int lua_getuservalue (lua_State *L, int idx) {
724 StkId o;
725 lua_lock(L);
726 o = index2addr(L, idx);
727 api_check(L, ttisfulluserdata(o), "full userdata expected");
728 getuservalue(L, uvalue(o), L->top);
729 api_incr_top(L);
730 lua_unlock(L);
731 return ttnov(L->top - 1);
732 }
733
734
735 /*
736 ** set functions (stack -> Lua)
737 */
738
739 /*
740 ** t[k] = value at the top of the stack (where 'k' is a string)
741 */
742 static void auxsetstr (lua_State *L, const TValue *t, const char *k) {
743 const TValue *aux;
744 TString *str = luaS_new(L, k);
745 api_checknelems(L, 1);
746 if (luaV_fastset(L, t, str, aux, luaH_getstr, L->top - 1))
747 L->top--; /* pop value */
748 else {
749 setsvalue2s(L, L->top, str); /* push 'str' (to make it a TValue) */
750 api_incr_top(L);
751 luaV_finishset(L, t, L->top - 1, L->top - 2, aux);
752 L->top -= 2; /* pop value and key */
753 }
754 lua_unlock(L); /* lock done by caller */
755 }
756
757
758 LUA_API void lua_setglobal (lua_State *L, const char *name) {
759 Table *reg = hvalue(&G(L)->l_registry);
760 lua_lock(L); /* unlock done in 'auxsetstr' */
761 auxsetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
762 }
763
764
765 LUA_API void lua_settable (lua_State *L, int idx) {
766 StkId t;
767 lua_lock(L);
768 api_checknelems(L, 2);
769 t = index2addr(L, idx);
770 luaV_settable(L, t, L->top - 2, L->top - 1);
771 L->top -= 2; /* pop index and value */
772 lua_unlock(L);
773 }
774
775
776 LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
777 lua_lock(L); /* unlock done in 'auxsetstr' */
778 auxsetstr(L, index2addr(L, idx), k);
779 }
780
781
782 LUA_API void lua_seti (lua_State *L, int idx, lua_Integer n) {
783 StkId t;
784 const TValue *aux;
785 lua_lock(L);
786 api_checknelems(L, 1);
787 t = index2addr(L, idx);
788 if (luaV_fastset(L, t, n, aux, luaH_getint, L->top - 1))
789 L->top--; /* pop value */
790 else {
791 setivalue(L->top, n);
792 api_incr_top(L);
793 luaV_finishset(L, t, L->top - 1, L->top - 2, aux);
794 L->top -= 2; /* pop value and key */
795 }
796 lua_unlock(L);
797 }
798
799
800 LUA_API void lua_rawset (lua_State *L, int idx) {
801 StkId o;
802 TValue *slot;
803 lua_lock(L);
804 api_checknelems(L, 2);
805 o = index2addr(L, idx);
806 api_check(L, ttistable(o), "table expected");
807 slot = luaH_set(L, hvalue(o), L->top - 2);
808 setobj2t(L, slot, L->top - 1);
809 invalidateTMcache(hvalue(o));
810 luaC_barrierback(L, hvalue(o), L->top-1);
811 L->top -= 2;
812 lua_unlock(L);
813 }
814
815
816 LUA_API void lua_rawseti (lua_State *L, int idx, lua_Integer n) {
817 StkId o;
818 lua_lock(L);
819 api_checknelems(L, 1);
820 o = index2addr(L, idx);
821 api_check(L, ttistable(o), "table expected");
822 luaH_setint(L, hvalue(o), n, L->top - 1);
823 luaC_barrierback(L, hvalue(o), L->top-1);
824 L->top--;
825 lua_unlock(L);
826 }
827
828
829 LUA_API void lua_rawsetp (lua_State *L, int idx, const void *p) {
830 StkId o;
831 TValue k, *slot;
832 lua_lock(L);
833 api_checknelems(L, 1);
834 o = index2addr(L, idx);
835 api_check(L, ttistable(o), "table expected");
836 setpvalue(&k, cast(void *, p));
837 slot = luaH_set(L, hvalue(o), &k);
838 setobj2t(L, slot, L->top - 1);
839 luaC_barrierback(L, hvalue(o), L->top - 1);
840 L->top--;
841 lua_unlock(L);
842 }
843
844
845 LUA_API int lua_setmetatable (lua_State *L, int objindex) {
846 TValue *obj;
847 Table *mt;
848 lua_lock(L);
849 api_checknelems(L, 1);
850 obj = index2addr(L, objindex);
851 if (ttisnil(L->top - 1))
852 mt = NULL;
853 else {
854 api_check(L, ttistable(L->top - 1), "table expected");
855 mt = hvalue(L->top - 1);
856 }
857 switch (ttnov(obj)) {
858 case LUA_TTABLE: {
859 hvalue(obj)->metatable = mt;
860 if (mt) {
861 luaC_objbarrier(L, gcvalue(obj), mt);
862 luaC_checkfinalizer(L, gcvalue(obj), mt);
863 }
864 break;
865 }
866 case LUA_TUSERDATA: {
867 uvalue(obj)->metatable = mt;
868 if (mt) {
869 luaC_objbarrier(L, uvalue(obj), mt);
870 luaC_checkfinalizer(L, gcvalue(obj), mt);
871 }
872 break;
873 }
874 default: {
875 G(L)->mt[ttnov(obj)] = mt;
876 break;
877 }
878 }
879 L->top--;
880 lua_unlock(L);
881 return 1;
882 }
883
884
885 LUA_API void lua_setuservalue (lua_State *L, int idx) {
886 StkId o;
887 lua_lock(L);
888 api_checknelems(L, 1);
889 o = index2addr(L, idx);
890 api_check(L, ttisfulluserdata(o), "full userdata expected");
891 setuservalue(L, uvalue(o), L->top - 1);
892 luaC_barrier(L, gcvalue(o), L->top - 1);
893 L->top--;
894 lua_unlock(L);
895 }
896
897
898 /*
899 ** 'load' and 'call' functions (run Lua code)
900 */
901
902
903 #define checkresults(L,na,nr) \
904 api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)), \
905 "results from function overflow current stack size")
906
907
908 LUA_API void lua_callk (lua_State *L, int nargs, int nresults,
909 lua_KContext ctx, lua_KFunction k) {
910 StkId func;
911 lua_lock(L);
912 api_check(L, k == NULL || !isLua(L->ci),
913 "cannot use continuations inside hooks");
914 api_checknelems(L, nargs+1);
915 api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
916 checkresults(L, nargs, nresults);
917 func = L->top - (nargs+1);
918 if (k != NULL && L->nny == 0) { /* need to prepare continuation? */
919 L->ci->u.c.k = k; /* save continuation */
920 L->ci->u.c.ctx = ctx; /* save context */
921 luaD_call(L, func, nresults); /* do the call */
922 }
923 else /* no continuation or no yieldable */
924 luaD_callnoyield(L, func, nresults); /* just do the call */
925 adjustresults(L, nresults);
926 lua_unlock(L);
927 }
928
929
930
931 /*
932 ** Execute a protected call.
933 */
934 struct CallS { /* data to 'f_call' */
935 StkId func;
936 int nresults;
937 };
938
939
940 static void f_call (lua_State *L, void *ud) {
941 struct CallS *c = cast(struct CallS *, ud);
942 luaD_callnoyield(L, c->func, c->nresults);
943 }
944
945
946
947 LUA_API int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc,
948 lua_KContext ctx, lua_KFunction k) {
949 struct CallS c;
950 int status;
951 ptrdiff_t func;
952 lua_lock(L);
953 api_check(L, k == NULL || !isLua(L->ci),
954 "cannot use continuations inside hooks");
955 api_checknelems(L, nargs+1);
956 api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
957 checkresults(L, nargs, nresults);
958 if (errfunc == 0)
959 func = 0;
960 else {
961 StkId o = index2addr(L, errfunc);
962 api_checkstackindex(L, errfunc, o);
963 func = savestack(L, o);
964 }
965 c.func = L->top - (nargs+1); /* function to be called */
966 if (k == NULL || L->nny > 0) { /* no continuation or no yieldable? */
967 c.nresults = nresults; /* do a 'conventional' protected call */
968 status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
969 }
970 else { /* prepare continuation (call is already protected by 'resume') */
971 CallInfo *ci = L->ci;
972 ci->u.c.k = k; /* save continuation */
973 ci->u.c.ctx = ctx; /* save context */
974 /* save information for error recovery */
975 ci->extra = savestack(L, c.func);
976 ci->u.c.old_errfunc = L->errfunc;
977 L->errfunc = func;
978 setoah(ci->callstatus, L->allowhook); /* save value of 'allowhook' */
979 ci->callstatus |= CIST_YPCALL; /* function can do error recovery */
980 luaD_call(L, c.func, nresults); /* do the call */
981 ci->callstatus &= ~CIST_YPCALL;
982 L->errfunc = ci->u.c.old_errfunc;
983 status = LUA_OK; /* if it is here, there were no errors */
984 }
985 adjustresults(L, nresults);
986 lua_unlock(L);
987 return status;
988 }
989
990
991 LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
992 const char *chunkname, const char *mode) {
993 ZIO z;
994 int status;
995 lua_lock(L);
996 if (!chunkname) chunkname = "?";
997 luaZ_init(L, &z, reader, data);
998 status = luaD_protectedparser(L, &z, chunkname, mode);
999 if (status == LUA_OK) { /* no errors? */
1000 LClosure *f = clLvalue(L->top - 1); /* get newly created function */
1001 if (f->nupvalues >= 1) { /* does it have an upvalue? */
1002 /* get global table from registry */
1003 Table *reg = hvalue(&G(L)->l_registry);
1004 const TValue *gt = luaH_getint(reg, LUA_RIDX_GLOBALS);
1005 /* set global table as 1st upvalue of 'f' (may be LUA_ENV) */
1006 setobj(L, f->upvals[0]->v, gt);
1007 luaC_upvalbarrier(L, f->upvals[0]);
1008 }
1009 }
1010 lua_unlock(L);
1011 return status;
1012 }
1013
1014
1015 LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data, int strip) {
1016 int status;
1017 TValue *o;
1018 lua_lock(L);
1019 api_checknelems(L, 1);
1020 o = L->top - 1;
1021 if (isLfunction(o))
1022 status = luaU_dump(L, getproto(o), writer, data, strip);
1023 else
1024 status = 1;
1025 lua_unlock(L);
1026 return status;
1027 }
1028
1029
1030 LUA_API int lua_status (lua_State *L) {
1031 return L->status;
1032 }
1033
1034
1035 /*
1036 ** Garbage-collection function
1037 */
1038
1039 LUA_API int lua_gc (lua_State *L, int what, int data) {
1040 int res = 0;
1041 global_State *g;
1042 lua_lock(L);
1043 g = G(L);
1044 switch (what) {
1045 case LUA_GCSTOP: {
1046 g->gcrunning = 0;
1047 break;
1048 }
1049 case LUA_GCRESTART: {
1050 luaE_setdebt(g, 0);
1051 g->gcrunning = 1;
1052 break;
1053 }
1054 case LUA_GCCOLLECT: {
1055 luaC_fullgc(L, 0);
1056 break;
1057 }
1058 case LUA_GCCOUNT: {
1059 /* GC values are expressed in Kbytes: #bytes/2^10 */
1060 res = cast_int(gettotalbytes(g) >> 10);
1061 break;
1062 }
1063 case LUA_GCCOUNTB: {
1064 res = cast_int(gettotalbytes(g) & 0x3ff);
1065 break;
1066 }
1067 case LUA_GCSTEP: {
1068 l_mem debt = 1; /* =1 to signal that it did an actual step */
1069 lu_byte oldrunning = g->gcrunning;
1070 g->gcrunning = 1; /* allow GC to run */
1071 if (data == 0) {
1072 luaE_setdebt(g, -GCSTEPSIZE); /* to do a "small" step */
1073 luaC_step(L);
1074 }
1075 else { /* add 'data' to total debt */
1076 debt = cast(l_mem, data) * 1024 + g->GCdebt;
1077 luaE_setdebt(g, debt);
1078 luaC_checkGC(L);
1079 }
1080 g->gcrunning = oldrunning; /* restore previous state */
1081 if (debt > 0 && g->gcstate == GCSpause) /* end of cycle? */
1082 res = 1; /* signal it */
1083 break;
1084 }
1085 case LUA_GCSETPAUSE: {
1086 res = g->gcpause;
1087 g->gcpause = data;
1088 break;
1089 }
1090 case LUA_GCSETSTEPMUL: {
1091 res = g->gcstepmul;
1092 if (data < 40) data = 40; /* avoid ridiculous low values (and 0) */
1093 g->gcstepmul = data;
1094 break;
1095 }
1096 case LUA_GCISRUNNING: {
1097 res = g->gcrunning;
1098 break;
1099 }
1100 default: res = -1; /* invalid option */
1101 }
1102 lua_unlock(L);
1103 return res;
1104 }
1105
1106
1107
1108 /*
1109 ** miscellaneous functions
1110 */
1111
1112
1113 LUA_API int lua_error (lua_State *L) {
1114 lua_lock(L);
1115 api_checknelems(L, 1);
1116 luaG_errormsg(L);
1117 /* code unreachable; will unlock when control actually leaves the kernel */
1118 return 0; /* to avoid warnings */
1119 }
1120
1121
1122 LUA_API int lua_next (lua_State *L, int idx) {
1123 StkId t;
1124 int more;
1125 lua_lock(L);
1126 t = index2addr(L, idx);
1127 api_check(L, ttistable(t), "table expected");
1128 more = luaH_next(L, hvalue(t), L->top - 1);
1129 if (more) {
1130 api_incr_top(L);
1131 }
1132 else /* no more elements */
1133 L->top -= 1; /* remove key */
1134 lua_unlock(L);
1135 return more;
1136 }
1137
1138
1139 LUA_API void lua_concat (lua_State *L, int n) {
1140 lua_lock(L);
1141 api_checknelems(L, n);
1142 if (n >= 2) {
1143 luaC_checkGC(L);
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 lua_unlock(L);
1152 }
1153
1154
1155 LUA_API void lua_len (lua_State *L, int idx) {
1156 StkId t;
1157 lua_lock(L);
1158 t = index2addr(L, idx);
1159 luaV_objlen(L, L->top, t);
1160 api_incr_top(L);
1161 lua_unlock(L);
1162 }
1163
1164
1165 LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
1166 lua_Alloc f;
1167 lua_lock(L);
1168 if (ud) *ud = G(L)->ud;
1169 f = G(L)->frealloc;
1170 lua_unlock(L);
1171 return f;
1172 }
1173
1174
1175 LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
1176 lua_lock(L);
1177 G(L)->ud = ud;
1178 G(L)->frealloc = f;
1179 lua_unlock(L);
1180 }
1181
1182
1183 LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
1184 Udata *u;
1185 lua_lock(L);
1186 luaC_checkGC(L);
1187 u = luaS_newudata(L, size);
1188 setuvalue(L, L->top, u);
1189 api_incr_top(L);
1190 lua_unlock(L);
1191 return getudatamem(u);
1192 }
1193
1194
1195
1196 static const char *aux_upvalue (StkId fi, int n, TValue **val,
1197 CClosure **owner, UpVal **uv) {
1198 switch (ttype(fi)) {
1199 case LUA_TCCL: { /* C closure */
1200 CClosure *f = clCvalue(fi);
1201 if (!(1 <= n && n <= f->nupvalues)) return NULL;
1202 *val = &f->upvalue[n-1];
1203 if (owner) *owner = f;
1204 return "";
1205 }
1206 case LUA_TLCL: { /* Lua closure */
1207 LClosure *f = clLvalue(fi);
1208 TString *name;
1209 Proto *p = f->p;
1210 if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
1211 *val = f->upvals[n-1]->v;
1212 if (uv) *uv = f->upvals[n - 1];
1213 name = p->upvalues[n-1].name;
1214 return (name == NULL) ? "(*no name)" : getstr(name);
1215 }
1216 default: return NULL; /* not a closure */
1217 }
1218 }
1219
1220
1221 LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
1222 const char *name;
1223 TValue *val = NULL; /* to avoid warnings */
1224 lua_lock(L);
1225 name = aux_upvalue(index2addr(L, funcindex), n, &val, NULL, NULL);
1226 if (name) {
1227 setobj2s(L, L->top, val);
1228 api_incr_top(L);
1229 }
1230 lua_unlock(L);
1231 return name;
1232 }
1233
1234
1235 LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
1236 const char *name;
1237 TValue *val = NULL; /* to avoid warnings */
1238 CClosure *owner = NULL;
1239 UpVal *uv = NULL;
1240 StkId fi;
1241 lua_lock(L);
1242 fi = index2addr(L, funcindex);
1243 api_checknelems(L, 1);
1244 name = aux_upvalue(fi, n, &val, &owner, &uv);
1245 if (name) {
1246 L->top--;
1247 setobj(L, val, L->top);
1248 if (owner) { luaC_barrier(L, owner, L->top); }
1249 else if (uv) { luaC_upvalbarrier(L, uv); }
1250 }
1251 lua_unlock(L);
1252 return name;
1253 }
1254
1255
1256 static UpVal **getupvalref (lua_State *L, int fidx, int n, LClosure **pf) {
1257 LClosure *f;
1258 StkId fi = index2addr(L, fidx);
1259 api_check(L, ttisLclosure(fi), "Lua function expected");
1260 f = clLvalue(fi);
1261 api_check(L, (1 <= n && n <= f->p->sizeupvalues), "invalid upvalue index");
1262 if (pf) *pf = f;
1263 return &f->upvals[n - 1]; /* get its upvalue pointer */
1264 }
1265
1266
1267 LUA_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, NULL);
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
1286 LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
1287 int fidx2, int n2) {
1288 LClosure *f1;
1289 UpVal **up1 = getupvalref(L, fidx1, n1, &f1);
1290 UpVal **up2 = getupvalref(L, fidx2, n2, NULL);
1291 luaC_upvdeccount(L, *up1);
1292 *up1 = *up2;
1293 (*up1)->refcount++;
1294 if (upisopen(*up1)) (*up1)->u.open.touched = 1;
1295 luaC_upvalbarrier(L, *up1);
1296 }
1297
1298
1299