lapi.c 32 KB

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  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. #define lapi_c
  7. #define LUA_CORE
  8. #include "lprefix.h"
  9. #include <stdarg.h>
  10. #include <string.h>
  11. #include "lua.h"
  12. #include "lapi.h"
  13. #include "ldebug.h"
  14. #include "ldo.h"
  15. #include "lfunc.h"
  16. #include "lgc.h"
  17. #include "lmem.h"
  18. #include "lobject.h"
  19. #include "lstate.h"
  20. #include "lstring.h"
  21. #include "ltable.h"
  22. #include "ltm.h"
  23. #include "lundump.h"
  24. #include "lvm.h"
  25. const char lua_ident[] =
  26. "$LuaVersion: " LUA_COPYRIGHT " $"
  27. "$LuaAuthors: " LUA_AUTHORS " $";
  28. /* value at a non-valid index */
  29. #define NONVALIDVALUE cast(TValue *, luaO_nilobject)
  30. /* corresponding test */
  31. #define isvalid(o) ((o) != luaO_nilobject)
  32. /* test for pseudo index */
  33. #define ispseudo(i) ((i) <= LUA_REGISTRYINDEX)
  34. /* test for upvalue */
  35. #define isupvalue(i) ((i) < LUA_REGISTRYINDEX)
  36. /* test for valid but not pseudo index */
  37. #define isstackindex(i, o) (isvalid(o) && !ispseudo(i))
  38. #define api_checkvalidindex(l,o) api_check(l, isvalid(o), "invalid index")
  39. #define api_checkstackindex(l, i, o) \
  40. api_check(l, isstackindex(i, o), "index not in the stack")
  41. static TValue *index2addr (lua_State *L, int idx) {
  42. CallInfo *ci = L->ci;
  43. if (idx > 0) {
  44. TValue *o = ci->func + idx;
  45. api_check(L, idx <= ci->top - (ci->func + 1), "unacceptable index");
  46. if (o >= L->top) return NONVALIDVALUE;
  47. else return o;
  48. }
  49. else if (!ispseudo(idx)) { /* negative index */
  50. api_check(L, idx != 0 && -idx <= L->top - (ci->func + 1), "invalid index");
  51. return L->top + idx;
  52. }
  53. else if (idx == LUA_REGISTRYINDEX)
  54. return &G(L)->l_registry;
  55. else { /* upvalues */
  56. idx = LUA_REGISTRYINDEX - idx;
  57. api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large");
  58. if (ttislcf(ci->func)) /* light C function? */
  59. return NONVALIDVALUE; /* it has no upvalues */
  60. else {
  61. CClosure *func = clCvalue(ci->func);
  62. return (idx <= func->nupvalues) ? &func->upvalue[idx-1] : NONVALIDVALUE;
  63. }
  64. }
  65. }
  66. /*
  67. ** to be called by 'lua_checkstack' in protected mode, to grow stack
  68. ** capturing memory errors
  69. */
  70. static void growstack (lua_State *L, void *ud) {
  71. int size = *(int *)ud;
  72. luaD_growstack(L, size);
  73. }
  74. LUA_API int lua_checkstack (lua_State *L, int n) {
  75. int res;
  76. CallInfo *ci = L->ci;
  77. lua_lock(L);
  78. api_check(L, n >= 0, "negative 'n'");
  79. if (L->stack_last - L->top > n) /* stack large enough? */
  80. res = 1; /* yes; check is OK */
  81. else { /* no; need to grow stack */
  82. int inuse = cast_int(L->top - L->stack) + EXTRA_STACK;
  83. if (inuse > LUAI_MAXSTACK - n) /* can grow without overflow? */
  84. res = 0; /* no */
  85. else /* try to grow stack */
  86. res = (luaD_rawrunprotected(L, &growstack, &n) == LUA_OK);
  87. }
  88. if (res && ci->top < L->top + n)
  89. ci->top = L->top + n; /* adjust frame top */
  90. lua_unlock(L);
  91. return res;
  92. }
  93. LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
  94. int i;
  95. if (from == to) return;
  96. lua_lock(to);
  97. api_checknelems(from, n);
  98. api_check(from, G(from) == G(to), "moving among independent states");
  99. api_check(from, to->ci->top - to->top >= n, "stack overflow");
  100. from->top -= n;
  101. for (i = 0; i < n; i++) {
  102. setobj2s(to, to->top, from->top + i);
  103. to->top++; /* stack already checked by previous 'api_check' */
  104. }
  105. lua_unlock(to);
  106. }
  107. LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
  108. lua_CFunction old;
  109. lua_lock(L);
  110. old = G(L)->panic;
  111. G(L)->panic = panicf;
  112. lua_unlock(L);
  113. return old;
  114. }
  115. LUA_API const lua_Number *lua_version (lua_State *L) {
  116. static const lua_Number version = LUA_VERSION_NUM;
  117. if (L == NULL) return &version;
  118. else return G(L)->version;
  119. }
  120. /*
  121. ** basic stack manipulation
  122. */
  123. /*
  124. ** convert an acceptable stack index into an absolute index
  125. */
  126. LUA_API int lua_absindex (lua_State *L, int idx) {
  127. return (idx > 0 || ispseudo(idx))
  128. ? idx
  129. : cast_int(L->top - L->ci->func) + idx;
  130. }
  131. LUA_API int lua_gettop (lua_State *L) {
  132. return cast_int(L->top - (L->ci->func + 1));
  133. }
  134. LUA_API void lua_settop (lua_State *L, int idx) {
  135. StkId func = L->ci->func;
  136. lua_lock(L);
  137. if (idx >= 0) {
  138. api_check(L, idx <= L->stack_last - (func + 1), "new top too large");
  139. while (L->top < (func + 1) + idx)
  140. setnilvalue(L->top++);
  141. L->top = (func + 1) + idx;
  142. }
  143. else {
  144. api_check(L, -(idx+1) <= (L->top - (func + 1)), "invalid new top");
  145. L->top += idx+1; /* 'subtract' index (index is negative) */
  146. }
  147. lua_unlock(L);
  148. }
  149. /*
  150. ** Reverse the stack segment from 'from' to 'to'
  151. ** (auxiliary to 'lua_rotate')
  152. */
  153. static void reverse (lua_State *L, StkId from, StkId to) {
  154. for (; from < to; from++, to--) {
  155. TValue temp;
  156. setobj(L, &temp, from);
  157. setobjs2s(L, from, to);
  158. setobj2s(L, to, &temp);
  159. }
  160. }
  161. /*
  162. ** Let x = AB, where A is a prefix of length 'n'. Then,
  163. ** rotate x n == BA. But BA == (A^r . B^r)^r.
  164. */
  165. LUA_API void lua_rotate (lua_State *L, int idx, int n) {
  166. StkId p, t, m;
  167. lua_lock(L);
  168. t = L->top - 1; /* end of stack segment being rotated */
  169. p = index2addr(L, idx); /* start of segment */
  170. api_checkstackindex(L, idx, p);
  171. api_check(L, (n >= 0 ? n : -n) <= (t - p + 1), "invalid 'n'");
  172. m = (n >= 0 ? t - n : p - n - 1); /* end of prefix */
  173. reverse(L, p, m); /* reverse the prefix with length 'n' */
  174. reverse(L, m + 1, t); /* reverse the suffix */
  175. reverse(L, p, t); /* reverse the entire segment */
  176. lua_unlock(L);
  177. }
  178. LUA_API void lua_copy (lua_State *L, int fromidx, int toidx) {
  179. TValue *fr, *to;
  180. lua_lock(L);
  181. fr = index2addr(L, fromidx);
  182. to = index2addr(L, toidx);
  183. api_checkvalidindex(L, to);
  184. setobj(L, to, fr);
  185. if (isupvalue(toidx)) /* function upvalue? */
  186. luaC_barrier(L, clCvalue(L->ci->func), fr);
  187. /* LUA_REGISTRYINDEX does not need gc barrier
  188. (collector revisits it before finishing collection) */
  189. lua_unlock(L);
  190. }
  191. LUA_API void lua_pushvalue (lua_State *L, int idx) {
  192. lua_lock(L);
  193. setobj2s(L, L->top, index2addr(L, idx));
  194. api_incr_top(L);
  195. lua_unlock(L);
  196. }
  197. /*
  198. ** access functions (stack -> C)
  199. */
  200. LUA_API int lua_type (lua_State *L, int idx) {
  201. StkId o = index2addr(L, idx);
  202. return (isvalid(o) ? ttnov(o) : LUA_TNONE);
  203. }
  204. LUA_API const char *lua_typename (lua_State *L, int t) {
  205. UNUSED(L);
  206. api_check(L, LUA_TNONE <= t && t < LUA_NUMTAGS, "invalid tag");
  207. return ttypename(t);
  208. }
  209. LUA_API int lua_iscfunction (lua_State *L, int idx) {
  210. StkId o = index2addr(L, idx);
  211. return (ttislcf(o) || (ttisCclosure(o)));
  212. }
  213. LUA_API int lua_isinteger (lua_State *L, int idx) {
  214. StkId o = index2addr(L, idx);
  215. return ttisinteger(o);
  216. }
  217. LUA_API int lua_isnumber (lua_State *L, int idx) {
  218. lua_Number n;
  219. const TValue *o = index2addr(L, idx);
  220. return tonumber(o, &n);
  221. }
  222. LUA_API int lua_isstring (lua_State *L, int idx) {
  223. const TValue *o = index2addr(L, idx);
  224. return (ttisstring(o) || cvt2str(o));
  225. }
  226. LUA_API int lua_isuserdata (lua_State *L, int idx) {
  227. const TValue *o = index2addr(L, idx);
  228. return (ttisfulluserdata(o) || ttislightuserdata(o));
  229. }
  230. LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
  231. StkId o1 = index2addr(L, index1);
  232. StkId o2 = index2addr(L, index2);
  233. return (isvalid(o1) && isvalid(o2)) ? luaV_rawequalobj(o1, o2) : 0;
  234. }
  235. LUA_API void lua_arith (lua_State *L, int op) {
  236. lua_lock(L);
  237. if (op != LUA_OPUNM && op != LUA_OPBNOT)
  238. api_checknelems(L, 2); /* all other operations expect two operands */
  239. else { /* for unary operations, add fake 2nd operand */
  240. api_checknelems(L, 1);
  241. setobjs2s(L, L->top, L->top - 1);
  242. api_incr_top(L);
  243. }
  244. /* first operand at top - 2, second at top - 1; result go to top - 2 */
  245. luaO_arith(L, op, L->top - 2, L->top - 1, L->top - 2);
  246. L->top--; /* remove second operand */
  247. lua_unlock(L);
  248. }
  249. LUA_API int lua_compare (lua_State *L, int index1, int index2, int op) {
  250. StkId o1, o2;
  251. int i = 0;
  252. lua_lock(L); /* may call tag method */
  253. o1 = index2addr(L, index1);
  254. o2 = index2addr(L, index2);
  255. if (isvalid(o1) && isvalid(o2)) {
  256. switch (op) {
  257. case LUA_OPEQ: i = luaV_equalobj(L, o1, o2); break;
  258. case LUA_OPLT: i = luaV_lessthan(L, o1, o2); break;
  259. case LUA_OPLE: i = luaV_lessequal(L, o1, o2); break;
  260. default: api_check(L, 0, "invalid option");
  261. }
  262. }
  263. lua_unlock(L);
  264. return i;
  265. }
  266. LUA_API size_t lua_stringtonumber (lua_State *L, const char *s) {
  267. size_t sz = luaO_str2num(s, L->top);
  268. if (sz != 0)
  269. api_incr_top(L);
  270. return sz;
  271. }
  272. LUA_API lua_Number lua_tonumberx (lua_State *L, int idx, int *pisnum) {
  273. lua_Number n;
  274. const TValue *o = index2addr(L, idx);
  275. int isnum = tonumber(o, &n);
  276. if (!isnum)
  277. n = 0; /* call to 'tonumber' may change 'n' even if it fails */
  278. if (pisnum) *pisnum = isnum;
  279. return n;
  280. }
  281. LUA_API lua_Integer lua_tointegerx (lua_State *L, int idx, int *pisnum) {
  282. lua_Integer res;
  283. const TValue *o = index2addr(L, idx);
  284. int isnum = tointeger(o, &res);
  285. if (!isnum)
  286. res = 0; /* call to 'tointeger' may change 'n' even if it fails */
  287. if (pisnum) *pisnum = isnum;
  288. return res;
  289. }
  290. LUA_API int lua_toboolean (lua_State *L, int idx) {
  291. const TValue *o = index2addr(L, idx);
  292. return !l_isfalse(o);
  293. }
  294. LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
  295. StkId o = index2addr(L, idx);
  296. if (!ttisstring(o)) {
  297. if (!cvt2str(o)) { /* not convertible? */
  298. if (len != NULL) *len = 0;
  299. return NULL;
  300. }
  301. lua_lock(L); /* 'luaO_tostring' may create a new string */
  302. luaO_tostring(L, o);
  303. luaC_checkGC(L);
  304. o = index2addr(L, idx); /* previous call may reallocate the stack */
  305. lua_unlock(L);
  306. }
  307. if (len != NULL)
  308. *len = vslen(o);
  309. return svalue(o);
  310. }
  311. LUA_API size_t lua_rawlen (lua_State *L, int idx) {
  312. StkId o = index2addr(L, idx);
  313. switch (ttype(o)) {
  314. case LUA_TSHRSTR: return getshrlen(tsvalue(o));
  315. case LUA_TLNGSTR: return tsvalue(o)->u.lnglen;
  316. case LUA_TUSERDATA: return uvalue(o)->len;
  317. case LUA_TTBLRAM: return luaH_getn(hvalue(o));
  318. default: return 0;
  319. }
  320. }
  321. LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
  322. StkId o = index2addr(L, idx);
  323. if (ttislcf(o)) return fvalue(o);
  324. else if (ttisCclosure(o))
  325. return clCvalue(o)->f;
  326. else return NULL; /* not a C function */
  327. }
  328. LUA_API void *lua_touserdata (lua_State *L, int idx) {
  329. StkId o = index2addr(L, idx);
  330. switch (ttnov(o)) {
  331. case LUA_TUSERDATA: return getudatamem(uvalue(o));
  332. case LUA_TLIGHTUSERDATA: return pvalue(o);
  333. default: return NULL;
  334. }
  335. }
  336. LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
  337. StkId o = index2addr(L, idx);
  338. return (!ttisthread(o)) ? NULL : thvalue(o);
  339. }
  340. LUA_API const void *lua_topointer (lua_State *L, int idx) {
  341. StkId o = index2addr(L, idx);
  342. switch (ttype(o)) {
  343. case LUA_TTBLRAM:
  344. case LUA_TTBLROF: return hvalue(o);
  345. case LUA_TLCL: return clLvalue(o);
  346. case LUA_TCCL: return clCvalue(o);
  347. case LUA_TLCF: return cast(void *, cast(size_t, fvalue(o)));
  348. case LUA_TTHREAD: return thvalue(o);
  349. case LUA_TUSERDATA: return getudatamem(uvalue(o));
  350. case LUA_TLIGHTUSERDATA: return pvalue(o);
  351. default: return NULL;
  352. }
  353. }
  354. /*
  355. ** push functions (C -> stack)
  356. */
  357. LUA_API void lua_pushnil (lua_State *L) {
  358. lua_lock(L);
  359. setnilvalue(L->top);
  360. api_incr_top(L);
  361. lua_unlock(L);
  362. }
  363. LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
  364. lua_lock(L);
  365. setfltvalue(L->top, n);
  366. api_incr_top(L);
  367. lua_unlock(L);
  368. }
  369. LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
  370. lua_lock(L);
  371. setivalue(L->top, n);
  372. api_incr_top(L);
  373. lua_unlock(L);
  374. }
  375. /*
  376. ** Pushes on the stack a string with given length. Avoid using 's' when
  377. ** 'len' == 0 (as 's' can be NULL in that case), due to later use of
  378. ** 'memcmp' and 'memcpy'.
  379. */
  380. LUA_API const char *lua_pushlstring (lua_State *L, const char *s, size_t len) {
  381. TString *ts;
  382. lua_lock(L);
  383. ts = (len == 0) ? luaS_new(L, "") : luaS_newlstr(L, s, len);
  384. setsvalue2s(L, L->top, ts);
  385. api_incr_top(L);
  386. luaC_checkGC(L);
  387. lua_unlock(L);
  388. return getstr(ts);
  389. }
  390. LUA_API const char *lua_pushstring (lua_State *L, const char *s) {
  391. lua_lock(L);
  392. if (s == NULL)
  393. setnilvalue(L->top);
  394. else {
  395. TString *ts;
  396. ts = luaS_new(L, s);
  397. setsvalue2s(L, L->top, ts);
  398. s = getstr(ts); /* internal copy's address */
  399. }
  400. api_incr_top(L);
  401. luaC_checkGC(L);
  402. lua_unlock(L);
  403. return s;
  404. }
  405. LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
  406. va_list argp) {
  407. const char *ret;
  408. lua_lock(L);
  409. ret = luaO_pushvfstring(L, fmt, argp);
  410. luaC_checkGC(L);
  411. lua_unlock(L);
  412. return ret;
  413. }
  414. LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
  415. const char *ret;
  416. va_list argp;
  417. lua_lock(L);
  418. va_start(argp, fmt);
  419. ret = luaO_pushvfstring(L, fmt, argp);
  420. va_end(argp);
  421. luaC_checkGC(L);
  422. lua_unlock(L);
  423. return ret;
  424. }
  425. LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
  426. lua_lock(L);
  427. if (n == 0) {
  428. setfvalue(L->top, fn);
  429. api_incr_top(L);
  430. }
  431. else {
  432. CClosure *cl;
  433. api_checknelems(L, n);
  434. api_check(L, n <= MAXUPVAL, "upvalue index too large");
  435. cl = luaF_newCclosure(L, n);
  436. cl->f = fn;
  437. L->top -= n;
  438. while (n--) {
  439. setobj2n(L, &cl->upvalue[n], L->top + n);
  440. /* does not need barrier because closure is white */
  441. }
  442. setclCvalue(L, L->top, cl);
  443. api_incr_top(L);
  444. luaC_checkGC(L);
  445. }
  446. lua_unlock(L);
  447. }
  448. LUA_API void lua_pushboolean (lua_State *L, int b) {
  449. lua_lock(L);
  450. setbvalue(L->top, (b != 0)); /* ensure that true is 1 */
  451. api_incr_top(L);
  452. lua_unlock(L);
  453. }
  454. LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
  455. lua_lock(L);
  456. setpvalue(L->top, p);
  457. api_incr_top(L);
  458. lua_unlock(L);
  459. }
  460. LUA_API int lua_pushthread (lua_State *L) {
  461. lua_lock(L);
  462. setthvalue(L, L->top, L);
  463. api_incr_top(L);
  464. lua_unlock(L);
  465. return (G(L)->mainthread == L);
  466. }
  467. LUA_API void lua_pushrotable (lua_State *L, const ROTable *t) {
  468. lua_lock(L);
  469. sethvalue(L, L->top, cast(Table *, t));
  470. api_incr_top(L);
  471. lua_unlock(L);
  472. }
  473. /*
  474. ** get functions (Lua -> stack)
  475. */
  476. static int auxgetstr (lua_State *L, const TValue *t, const char *k) {
  477. const TValue *slot;
  478. TString *str = luaS_new(L, k);
  479. if (luaV_fastget(L, t, str, slot, luaH_getstr)) {
  480. setobj2s(L, L->top, slot);
  481. api_incr_top(L);
  482. }
  483. else {
  484. setsvalue2s(L, L->top, str);
  485. api_incr_top(L);
  486. luaV_finishget(L, t, L->top - 1, L->top - 1, slot);
  487. }
  488. lua_unlock(L);
  489. return ttnov(L->top - 1);
  490. }
  491. LUA_API int lua_getglobal (lua_State *L, const char *name) {
  492. Table *reg = hvalue(&G(L)->l_registry);
  493. lua_lock(L);
  494. return auxgetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
  495. }
  496. LUA_API int lua_gettable (lua_State *L, int idx) {
  497. StkId t;
  498. lua_lock(L);
  499. t = index2addr(L, idx);
  500. luaV_gettable(L, t, L->top - 1, L->top - 1);
  501. lua_unlock(L);
  502. return ttnov(L->top - 1);
  503. }
  504. LUA_API int lua_getfield (lua_State *L, int idx, const char *k) {
  505. lua_lock(L);
  506. return auxgetstr(L, index2addr(L, idx), k);
  507. }
  508. LUA_API int lua_geti (lua_State *L, int idx, lua_Integer n) {
  509. StkId t;
  510. const TValue *slot;
  511. lua_lock(L);
  512. t = index2addr(L, idx);
  513. if (luaV_fastget(L, t, n, slot, luaH_getint)) {
  514. setobj2s(L, L->top, slot);
  515. api_incr_top(L);
  516. }
  517. else {
  518. setivalue(L->top, n);
  519. api_incr_top(L);
  520. luaV_finishget(L, t, L->top - 1, L->top - 1, slot);
  521. }
  522. lua_unlock(L);
  523. return ttnov(L->top - 1);
  524. }
  525. LUA_API int lua_rawget (lua_State *L, int idx) {
  526. StkId t;
  527. lua_lock(L);
  528. t = index2addr(L, idx);
  529. api_check(L, ttistable(t), "table expected");
  530. setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
  531. lua_unlock(L);
  532. return ttnov(L->top - 1);
  533. }
  534. LUA_API int lua_rawgeti (lua_State *L, int idx, lua_Integer n) {
  535. StkId t;
  536. lua_lock(L);
  537. t = index2addr(L, idx);
  538. api_check(L, ttistable(t), "table expected");
  539. setobj2s(L, L->top, luaH_getint(hvalue(t), n));
  540. api_incr_top(L);
  541. lua_unlock(L);
  542. return ttnov(L->top - 1);
  543. }
  544. LUA_API int lua_rawgetp (lua_State *L, int idx, const void *p) {
  545. StkId t;
  546. TValue k;
  547. lua_lock(L);
  548. t = index2addr(L, idx);
  549. api_check(L, ttistable(t), "table expected");
  550. setpvalue(&k, cast(void *, p));
  551. setobj2s(L, L->top, luaH_get(hvalue(t), &k));
  552. api_incr_top(L);
  553. lua_unlock(L);
  554. return ttnov(L->top - 1);
  555. }
  556. LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
  557. Table *t;
  558. lua_lock(L);
  559. t = luaH_new(L);
  560. sethvalue(L, L->top, t);
  561. api_incr_top(L);
  562. if (narray > 0 || nrec > 0)
  563. luaH_resize(L, t, narray, nrec);
  564. luaC_checkGC(L);
  565. lua_unlock(L);
  566. }
  567. LUA_API int lua_getmetatable (lua_State *L, int objindex) {
  568. const TValue *obj;
  569. Table *mt;
  570. int res = 0;
  571. lua_lock(L);
  572. obj = index2addr(L, objindex);
  573. switch (ttnov(obj)) {
  574. case LUA_TTABLE:
  575. mt = hvalue(obj)->metatable;
  576. break;
  577. case LUA_TUSERDATA:
  578. mt = uvalue(obj)->metatable;
  579. break;
  580. default:
  581. mt = G(L)->mt[ttnov(obj)];
  582. break;
  583. }
  584. if (mt != NULL) {
  585. sethvalue(L, L->top, mt);
  586. api_incr_top(L);
  587. res = 1;
  588. }
  589. lua_unlock(L);
  590. return res;
  591. }
  592. LUA_API int lua_getuservalue (lua_State *L, int idx) {
  593. StkId o;
  594. lua_lock(L);
  595. o = index2addr(L, idx);
  596. api_check(L, ttisfulluserdata(o), "full userdata expected");
  597. getuservalue(L, uvalue(o), L->top);
  598. api_incr_top(L);
  599. lua_unlock(L);
  600. return ttnov(L->top - 1);
  601. }
  602. /*
  603. ** set functions (stack -> Lua)
  604. */
  605. /*
  606. ** t[k] = value at the top of the stack (where 'k' is a string)
  607. */
  608. static void auxsetstr (lua_State *L, const TValue *t, const char *k) {
  609. const TValue *slot;
  610. TString *str = luaS_new(L, k);
  611. api_checknelems(L, 1);
  612. if (luaV_fastset(L, t, str, slot, luaH_getstr, L->top - 1))
  613. L->top--; /* pop value */
  614. else {
  615. setsvalue2s(L, L->top, str); /* push 'str' (to make it a TValue) */
  616. api_incr_top(L);
  617. luaV_finishset(L, t, L->top - 1, L->top - 2, slot);
  618. L->top -= 2; /* pop value and key */
  619. }
  620. lua_unlock(L); /* lock done by caller */
  621. }
  622. LUA_API void lua_setglobal (lua_State *L, const char *name) {
  623. Table *reg = hvalue(&G(L)->l_registry);
  624. lua_lock(L); /* unlock done in 'auxsetstr' */
  625. auxsetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
  626. }
  627. LUA_API void lua_settable (lua_State *L, int idx) {
  628. StkId t;
  629. lua_lock(L);
  630. api_checknelems(L, 2);
  631. t = index2addr(L, idx);
  632. luaV_settable(L, t, L->top - 2, L->top - 1);
  633. L->top -= 2; /* pop index and value */
  634. lua_unlock(L);
  635. }
  636. LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
  637. lua_lock(L); /* unlock done in 'auxsetstr' */
  638. auxsetstr(L, index2addr(L, idx), k);
  639. }
  640. LUA_API void lua_seti (lua_State *L, int idx, lua_Integer n) {
  641. StkId t;
  642. const TValue *slot;
  643. lua_lock(L);
  644. api_checknelems(L, 1);
  645. t = index2addr(L, idx);
  646. if (luaV_fastset(L, t, n, slot, luaH_getint, L->top - 1))
  647. L->top--; /* pop value */
  648. else {
  649. setivalue(L->top, n);
  650. api_incr_top(L);
  651. luaV_finishset(L, t, L->top - 1, L->top - 2, slot);
  652. L->top -= 2; /* pop value and key */
  653. }
  654. lua_unlock(L);
  655. }
  656. LUA_API void lua_rawset (lua_State *L, int idx) {
  657. StkId o;
  658. TValue *slot;
  659. lua_lock(L);
  660. api_checknelems(L, 2);
  661. o = index2addr(L, idx);
  662. api_check(L, ttisrwtable(o), "RW table expected");
  663. slot = luaH_set(L, hvalue(o), L->top - 2);
  664. setobj2t(L, slot, L->top - 1);
  665. invalidateTMcache(hvalue(o));
  666. luaC_barrierback(L, hvalue(o), L->top-1);
  667. L->top -= 2;
  668. lua_unlock(L);
  669. }
  670. LUA_API void lua_rawseti (lua_State *L, int idx, lua_Integer n) {
  671. StkId o;
  672. lua_lock(L);
  673. api_checknelems(L, 1);
  674. o = index2addr(L, idx);
  675. api_check(L, ttisrwtable(o), "RW table expected");
  676. luaH_setint(L, hvalue(o), n, L->top - 1);
  677. luaC_barrierback(L, hvalue(o), L->top-1);
  678. L->top--;
  679. lua_unlock(L);
  680. }
  681. LUA_API void lua_rawsetp (lua_State *L, int idx, const void *p) {
  682. StkId o;
  683. TValue k, *slot;
  684. lua_lock(L);
  685. api_checknelems(L, 1);
  686. o = index2addr(L, idx);
  687. api_check(L, ttisrwtable(o), "RW table expected");
  688. setpvalue(&k, cast(void *, p));
  689. slot = luaH_set(L, hvalue(o), &k);
  690. setobj2t(L, slot, L->top - 1);
  691. luaC_barrierback(L, hvalue(o), L->top - 1);
  692. L->top--;
  693. lua_unlock(L);
  694. }
  695. LUA_API int lua_setmetatable (lua_State *L, int objindex) {
  696. TValue *obj;
  697. Table *mt;
  698. lua_lock(L);
  699. api_checknelems(L, 1);
  700. obj = index2addr(L, objindex);
  701. if (ttisnil(L->top - 1))
  702. mt = NULL;
  703. else {
  704. api_check(L, ttistable(L->top - 1), "table expected");
  705. mt = hvalue(L->top - 1);
  706. }
  707. switch (ttype(obj)) {
  708. case LUA_TTBLRAM: {
  709. hvalue(obj)->metatable = mt;
  710. if (mt) {
  711. luaC_objbarrier(L, gcvalue(obj), mt);
  712. luaC_checkfinalizer(L, gcvalue(obj), mt);
  713. }
  714. break;
  715. }
  716. case LUA_TTBLROF: {
  717. luai_apicheck(L, "RW table expected");
  718. }
  719. case LUA_TUSERDATA: {
  720. uvalue(obj)->metatable = mt;
  721. if (mt) {
  722. luaC_objbarrier(L, uvalue(obj), mt);
  723. luaC_checkfinalizer(L, gcvalue(obj), mt);
  724. }
  725. break;
  726. }
  727. default: {
  728. G(L)->mt[ttnov(obj)] = mt;
  729. break;
  730. }
  731. }
  732. L->top--;
  733. lua_unlock(L);
  734. return 1;
  735. }
  736. LUA_API void lua_setuservalue (lua_State *L, int idx) {
  737. StkId o;
  738. lua_lock(L);
  739. api_checknelems(L, 1);
  740. o = index2addr(L, idx);
  741. api_check(L, ttisfulluserdata(o), "full userdata expected");
  742. setuservalue(L, uvalue(o), L->top - 1);
  743. luaC_barrier(L, gcvalue(o), L->top - 1);
  744. L->top--;
  745. lua_unlock(L);
  746. }
  747. /*
  748. ** 'load' and 'call' functions (run Lua code)
  749. */
  750. #define checkresults(L,na,nr) \
  751. api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)), \
  752. "results from function overflow current stack size")
  753. LUA_API void lua_callk (lua_State *L, int nargs, int nresults,
  754. lua_KContext ctx, lua_KFunction k) {
  755. StkId func;
  756. lua_lock(L);
  757. api_check(L, k == NULL || !isLua(L->ci),
  758. "cannot use continuations inside hooks");
  759. api_checknelems(L, nargs+1);
  760. api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
  761. checkresults(L, nargs, nresults);
  762. func = L->top - (nargs+1);
  763. if (k != NULL && L->nny == 0) { /* need to prepare continuation? */
  764. L->ci->u.c.k = k; /* save continuation */
  765. L->ci->u.c.ctx = ctx; /* save context */
  766. luaD_call(L, func, nresults); /* do the call */
  767. }
  768. else /* no continuation or no yieldable */
  769. luaD_callnoyield(L, func, nresults); /* just do the call */
  770. adjustresults(L, nresults);
  771. lua_unlock(L);
  772. }
  773. /*
  774. ** Execute a protected call.
  775. */
  776. struct CallS { /* data to 'f_call' */
  777. StkId func;
  778. int nresults;
  779. };
  780. static void f_call (lua_State *L, void *ud) {
  781. struct CallS *c = cast(struct CallS *, ud);
  782. luaD_callnoyield(L, c->func, c->nresults);
  783. }
  784. LUA_API int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc,
  785. lua_KContext ctx, lua_KFunction k) {
  786. struct CallS c;
  787. int status;
  788. ptrdiff_t func;
  789. lua_lock(L);
  790. api_check(L, k == NULL || !isLua(L->ci),
  791. "cannot use continuations inside hooks");
  792. api_checknelems(L, nargs+1);
  793. api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
  794. checkresults(L, nargs, nresults);
  795. if (errfunc == 0)
  796. func = 0;
  797. else {
  798. StkId o = index2addr(L, errfunc);
  799. api_checkstackindex(L, errfunc, o);
  800. func = savestack(L, o);
  801. }
  802. c.func = L->top - (nargs+1); /* function to be called */
  803. if (k == NULL || L->nny > 0) { /* no continuation or no yieldable? */
  804. c.nresults = nresults; /* do a 'conventional' protected call */
  805. status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
  806. }
  807. else { /* prepare continuation (call is already protected by 'resume') */
  808. CallInfo *ci = L->ci;
  809. ci->u.c.k = k; /* save continuation */
  810. ci->u.c.ctx = ctx; /* save context */
  811. /* save information for error recovery */
  812. ci->extra = savestack(L, c.func);
  813. ci->u.c.old_errfunc = L->errfunc;
  814. L->errfunc = func;
  815. setoah(ci->callstatus, L->allowhook); /* save value of 'allowhook' */
  816. ci->callstatus |= CIST_YPCALL; /* function can do error recovery */
  817. luaD_call(L, c.func, nresults); /* do the call */
  818. ci->callstatus &= ~CIST_YPCALL;
  819. L->errfunc = ci->u.c.old_errfunc;
  820. status = LUA_OK; /* if it is here, there were no errors */
  821. }
  822. adjustresults(L, nresults);
  823. lua_unlock(L);
  824. return status;
  825. }
  826. LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
  827. const char *chunkname, const char *mode) {
  828. ZIO z;
  829. int status;
  830. lua_lock(L);
  831. if (!chunkname) chunkname = "?";
  832. luaZ_init(L, &z, reader, data);
  833. status = luaD_protectedparser(L, &z, chunkname, mode);
  834. if (status == LUA_OK) { /* no errors? */
  835. LClosure *f = clLvalue(L->top - 1); /* get newly created function */
  836. if (f->nupvalues >= 1) { /* does it have an upvalue? */
  837. /* get global table from registry */
  838. Table *reg = hvalue(&G(L)->l_registry);
  839. const TValue *gt = luaH_getint(reg, LUA_RIDX_GLOBALS);
  840. /* set global table as 1st upvalue of 'f' (may be LUA_ENV) */
  841. setobj(L, f->upvals[0]->v, gt);
  842. luaC_upvalbarrier(L, f->upvals[0]);
  843. }
  844. }
  845. lua_unlock(L);
  846. return status;
  847. }
  848. LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data, int strip) {
  849. int status;
  850. TValue *o;
  851. lua_lock(L);
  852. api_checknelems(L, 1);
  853. o = L->top - 1;
  854. if (strip == -1)
  855. strip = G(L)->stripdefault;
  856. if (isLfunction(o))
  857. status = luaU_dump(L, getproto(o), writer, data, strip);
  858. else
  859. status = 1;
  860. lua_unlock(L);
  861. return status;
  862. }
  863. LUA_API int lua_stripdebug (lua_State *L, int stripping){
  864. TValue *o = L->top - 1;
  865. Proto *p = NULL;
  866. int res = -1;
  867. lua_lock(L);
  868. api_checknelems(L, 1);
  869. if (isLfunction(o)) {
  870. p = getproto(o);
  871. if (p && !isLFSobj(p) && (unsigned) stripping < 3 ) {
  872. // found a valid proto to strip
  873. res = luaU_stripdebug(L, p, stripping, 1);
  874. }
  875. } else if (ttisnil(L->top - 1)) {
  876. // get or set the default strip level
  877. if ((unsigned) stripping < 3)
  878. G(L)->stripdefault = stripping;
  879. res = G(L)->stripdefault;
  880. }
  881. L->top--;
  882. lua_unlock(L);
  883. return res;
  884. }
  885. LUA_API int lua_status (lua_State *L) {
  886. return L->status;
  887. }
  888. /*
  889. ** Garbage-collection function
  890. */
  891. LUA_API int lua_gc (lua_State *L, int what, int data) {
  892. int res = 0;
  893. global_State *g;
  894. lua_lock(L);
  895. g = G(L);
  896. switch (what) {
  897. case LUA_GCSTOP: {
  898. g->gcrunning = 0;
  899. break;
  900. }
  901. case LUA_GCRESTART: {
  902. luaE_setdebt(g, 0);
  903. g->gcrunning = 1;
  904. break;
  905. }
  906. case LUA_GCCOLLECT: {
  907. luaC_fullgc(L, 0);
  908. break;
  909. }
  910. case LUA_GCCOUNT: {
  911. /* GC values are expressed in Kbytes: #bytes/2^10 */
  912. res = cast_int(gettotalbytes(g) >> 10);
  913. break;
  914. }
  915. case LUA_GCCOUNTB: {
  916. res = cast_int(gettotalbytes(g) & 0x3ff);
  917. break;
  918. }
  919. case LUA_GCSTEP: {
  920. l_mem debt = 1; /* =1 to signal that it did an actual step */
  921. lu_byte oldrunning = g->gcrunning;
  922. g->gcrunning = 1; /* allow GC to run */
  923. if (data == 0) {
  924. luaE_setdebt(g, -GCSTEPSIZE); /* to do a "small" step */
  925. luaC_step(L);
  926. }
  927. else { /* add 'data' to total debt */
  928. debt = cast(l_mem, data) * 1024 + g->GCdebt;
  929. luaE_setdebt(g, debt);
  930. luaC_checkGC(L);
  931. }
  932. g->gcrunning = oldrunning; /* restore previous state */
  933. if (debt > 0 && g->gcstate == GCSpause) /* end of cycle? */
  934. res = 1; /* signal it */
  935. break;
  936. }
  937. case LUA_GCSETPAUSE: {
  938. res = g->gcpause;
  939. g->gcpause = data;
  940. break;
  941. }
  942. case LUA_GCSETSTEPMUL: {
  943. res = g->gcstepmul;
  944. if (data < 40) data = 40; /* avoid ridiculous low values (and 0) */
  945. g->gcstepmul = data;
  946. break;
  947. }
  948. case LUA_GCSETMEMLIMIT: {
  949. /* GC values are expressed in Kbytes: #bytes/2^10 */
  950. l_mem new_memlimit = cast(l_mem, data) << 10;
  951. if(new_memlimit > lua_freeheap()) /* run a full GC */
  952. luaC_fullgc(L, 0);
  953. g->gcmemfreeboard = new_memlimit;
  954. /* new memlimit might be > then requested memlimit. */
  955. res = cast_int(new_memlimit >> 10);
  956. break;
  957. }
  958. case LUA_GCISRUNNING: {
  959. res = g->gcrunning;
  960. break;
  961. }
  962. default: res = -1; /* invalid option */
  963. }
  964. lua_unlock(L);
  965. return res;
  966. }
  967. /*
  968. ** miscellaneous functions
  969. */
  970. LUA_API int lua_error (lua_State *L) {
  971. lua_lock(L);
  972. api_checknelems(L, 1);
  973. luaG_errormsg(L);
  974. /* code unreachable; will unlock when control actually leaves the kernel */
  975. return 0; /* to avoid warnings */
  976. }
  977. LUA_API int lua_next (lua_State *L, int idx) {
  978. StkId t;
  979. int more;
  980. lua_lock(L);
  981. t = index2addr(L, idx);
  982. api_check(L, ttistable(t), "table expected");
  983. more = luaH_next(L, hvalue(t), L->top - 1);
  984. if (more) {
  985. api_incr_top(L);
  986. }
  987. else /* no more elements */
  988. L->top -= 1; /* remove key */
  989. lua_unlock(L);
  990. return more;
  991. }
  992. LUA_API void lua_concat (lua_State *L, int n) {
  993. lua_lock(L);
  994. api_checknelems(L, n);
  995. if (n >= 2) {
  996. luaV_concat(L, n);
  997. }
  998. else if (n == 0) { /* push empty string */
  999. setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
  1000. api_incr_top(L);
  1001. }
  1002. /* else n == 1; nothing to do */
  1003. luaC_checkGC(L);
  1004. lua_unlock(L);
  1005. }
  1006. LUA_API void lua_len (lua_State *L, int idx) {
  1007. StkId t;
  1008. lua_lock(L);
  1009. t = index2addr(L, idx);
  1010. luaV_objlen(L, L->top, t);
  1011. api_incr_top(L);
  1012. lua_unlock(L);
  1013. }
  1014. LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
  1015. lua_Alloc f;
  1016. lua_lock(L);
  1017. if (ud) *ud = G(L)->ud;
  1018. f = G(L)->frealloc;
  1019. lua_unlock(L);
  1020. return f;
  1021. }
  1022. LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
  1023. lua_lock(L);
  1024. G(L)->ud = ud;
  1025. G(L)->frealloc = f;
  1026. lua_unlock(L);
  1027. }
  1028. LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
  1029. Udata *u;
  1030. lua_lock(L);
  1031. u = luaS_newudata(L, size);
  1032. setuvalue(L, L->top, u);
  1033. api_incr_top(L);
  1034. luaC_checkGC(L);
  1035. lua_unlock(L);
  1036. return getudatamem(u);
  1037. }
  1038. static const char *aux_upvalue (StkId fi, int n, TValue **val,
  1039. CClosure **owner, UpVal **uv) {
  1040. switch (ttype(fi)) {
  1041. case LUA_TCCL: { /* C closure */
  1042. CClosure *f = clCvalue(fi);
  1043. if (!(1 <= n && n <= f->nupvalues)) return NULL;
  1044. *val = &f->upvalue[n-1];
  1045. if (owner) *owner = f;
  1046. return "";
  1047. }
  1048. case LUA_TLCL: { /* Lua closure */
  1049. LClosure *f = clLvalue(fi);
  1050. TString *name;
  1051. Proto *p = f->p;
  1052. if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
  1053. *val = f->upvals[n-1]->v;
  1054. if (uv) *uv = f->upvals[n - 1];
  1055. name = p->upvalues[n-1].name;
  1056. return (name == NULL) ? "(*no name)" : getstr(name);
  1057. }
  1058. default: return NULL; /* not a closure */
  1059. }
  1060. }
  1061. LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
  1062. const char *name;
  1063. TValue *val = NULL; /* to avoid warnings */
  1064. lua_lock(L);
  1065. name = aux_upvalue(index2addr(L, funcindex), n, &val, NULL, NULL);
  1066. if (name) {
  1067. setobj2s(L, L->top, val);
  1068. api_incr_top(L);
  1069. }
  1070. lua_unlock(L);
  1071. return name;
  1072. }
  1073. LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
  1074. const char *name;
  1075. TValue *val = NULL; /* to avoid warnings */
  1076. CClosure *owner = NULL;
  1077. UpVal *uv = NULL;
  1078. StkId fi;
  1079. lua_lock(L);
  1080. fi = index2addr(L, funcindex);
  1081. api_checknelems(L, 1);
  1082. name = aux_upvalue(fi, n, &val, &owner, &uv);
  1083. if (name) {
  1084. L->top--;
  1085. setobj(L, val, L->top);
  1086. if (owner) { luaC_barrier(L, owner, L->top); }
  1087. else if (uv) { luaC_upvalbarrier(L, uv); }
  1088. }
  1089. lua_unlock(L);
  1090. return name;
  1091. }
  1092. static UpVal **getupvalref (lua_State *L, int fidx, int n, LClosure **pf) {
  1093. LClosure *f;
  1094. StkId fi = index2addr(L, fidx);
  1095. api_check(L, ttisLclosure(fi), "Lua function expected");
  1096. f = clLvalue(fi);
  1097. api_check(L, (1 <= n && n <= f->p->sizeupvalues), "invalid upvalue index");
  1098. if (pf) *pf = f;
  1099. return &f->upvals[n - 1]; /* get its upvalue pointer */
  1100. }
  1101. LUA_API void *lua_upvalueid (lua_State *L, int fidx, int n) {
  1102. StkId fi = index2addr(L, fidx);
  1103. switch (ttype(fi)) {
  1104. case LUA_TLCL: { /* lua closure */
  1105. return *getupvalref(L, fidx, n, NULL);
  1106. }
  1107. case LUA_TCCL: { /* C closure */
  1108. CClosure *f = clCvalue(fi);
  1109. api_check(L, 1 <= n && n <= f->nupvalues, "invalid upvalue index");
  1110. return &f->upvalue[n - 1];
  1111. }
  1112. default: {
  1113. api_check(L, 0, "closure expected");
  1114. return NULL;
  1115. }
  1116. }
  1117. }
  1118. LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
  1119. int fidx2, int n2) {
  1120. LClosure *f1;
  1121. UpVal **up1 = getupvalref(L, fidx1, n1, &f1);
  1122. UpVal **up2 = getupvalref(L, fidx2, n2, NULL);
  1123. luaC_upvdeccount(L, *up1);
  1124. *up1 = *up2;
  1125. (*up1)->refcount++;
  1126. if (upisopen(*up1)) (*up1)->u.open.touched = 1;
  1127. luaC_upvalbarrier(L, *up1);
  1128. }