lbaselib.c 15 KB

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  1. /*
  2. ** $Id: lbaselib.c $
  3. ** Basic library
  4. ** See Copyright Notice in lua.h
  5. */
  6. #define lbaselib_c
  7. #define LUA_LIB
  8. #include "lprefix.h"
  9. #include <ctype.h>
  10. #include <stdio.h>
  11. #include <stdlib.h>
  12. #include <string.h>
  13. #include "lua.h"
  14. #include "lauxlib.h"
  15. #include "lualib.h"
  16. static int luaB_print (lua_State *L) {
  17. int n = lua_gettop(L); /* number of arguments */
  18. int i;
  19. for (i = 1; i <= n; i++) { /* for each argument */
  20. size_t l;
  21. const char *s = luaL_tolstring(L, i, &l); /* convert it to string */
  22. if (i > 1) /* not the first element? */
  23. lua_writestring("\t", 1); /* add a tab before it */
  24. lua_writestring(s, l); /* print it */
  25. lua_pop(L, 1); /* pop result */
  26. }
  27. lua_writeline();
  28. return 0;
  29. }
  30. /*
  31. ** Creates a warning with all given arguments.
  32. ** Check first for errors; otherwise an error may interrupt
  33. ** the composition of a warning, leaving it unfinished.
  34. */
  35. static int luaB_warn (lua_State *L) {
  36. int n = lua_gettop(L); /* number of arguments */
  37. int i;
  38. luaL_checkstring(L, 1); /* at least one argument */
  39. for (i = 2; i <= n; i++)
  40. luaL_checkstring(L, i); /* make sure all arguments are strings */
  41. for (i = 1; i < n; i++) /* compose warning */
  42. lua_warning(L, lua_tostring(L, i), 1);
  43. lua_warning(L, lua_tostring(L, n), 0); /* close warning */
  44. return 0;
  45. }
  46. #define SPACECHARS " \f\n\r\t\v"
  47. static const char *b_str2int (const char *s, int base, lua_Integer *pn) {
  48. lua_Unsigned n = 0;
  49. int neg = 0;
  50. s += strspn(s, SPACECHARS); /* skip initial spaces */
  51. if (*s == '-') { s++; neg = 1; } /* handle sign */
  52. else if (*s == '+') s++;
  53. if (!isalnum((unsigned char)*s)) /* no digit? */
  54. return NULL;
  55. do {
  56. int digit = (isdigit((unsigned char)*s)) ? *s - '0'
  57. : (toupper((unsigned char)*s) - 'A') + 10;
  58. if (digit >= base) return NULL; /* invalid numeral */
  59. n = n * base + digit;
  60. s++;
  61. } while (isalnum((unsigned char)*s));
  62. s += strspn(s, SPACECHARS); /* skip trailing spaces */
  63. *pn = (lua_Integer)((neg) ? (0u - n) : n);
  64. return s;
  65. }
  66. static int luaB_tonumber (lua_State *L) {
  67. if (lua_isnoneornil(L, 2)) { /* standard conversion? */
  68. if (lua_type(L, 1) == LUA_TNUMBER) { /* already a number? */
  69. lua_settop(L, 1); /* yes; return it */
  70. return 1;
  71. }
  72. else {
  73. size_t l;
  74. const char *s = lua_tolstring(L, 1, &l);
  75. if (s != NULL && lua_stringtonumber(L, s) == l + 1)
  76. return 1; /* successful conversion to number */
  77. /* else not a number */
  78. luaL_checkany(L, 1); /* (but there must be some parameter) */
  79. }
  80. }
  81. else {
  82. size_t l;
  83. const char *s;
  84. lua_Integer n = 0; /* to avoid warnings */
  85. lua_Integer base = luaL_checkinteger(L, 2);
  86. luaL_checktype(L, 1, LUA_TSTRING); /* no numbers as strings */
  87. s = lua_tolstring(L, 1, &l);
  88. luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
  89. if (b_str2int(s, (int)base, &n) == s + l) {
  90. lua_pushinteger(L, n);
  91. return 1;
  92. } /* else not a number */
  93. } /* else not a number */
  94. luaL_pushfail(L); /* not a number */
  95. return 1;
  96. }
  97. static int luaB_error (lua_State *L) {
  98. int level = (int)luaL_optinteger(L, 2, 1);
  99. lua_settop(L, 1);
  100. if (lua_type(L, 1) == LUA_TSTRING && level > 0) {
  101. luaL_where(L, level); /* add extra information */
  102. lua_pushvalue(L, 1);
  103. lua_concat(L, 2);
  104. }
  105. return lua_error(L);
  106. }
  107. static int luaB_getmetatable (lua_State *L) {
  108. luaL_checkany(L, 1);
  109. if (!lua_getmetatable(L, 1)) {
  110. lua_pushnil(L);
  111. return 1; /* no metatable */
  112. }
  113. luaL_getmetafield(L, 1, "__metatable");
  114. return 1; /* returns either __metatable field (if present) or metatable */
  115. }
  116. static int luaB_setmetatable (lua_State *L) {
  117. int t = lua_type(L, 2);
  118. luaL_checktype(L, 1, LUA_TTABLE);
  119. luaL_argexpected(L, t == LUA_TNIL || t == LUA_TTABLE, 2, "nil or table");
  120. if (l_unlikely(luaL_getmetafield(L, 1, "__metatable") != LUA_TNIL))
  121. return luaL_error(L, "cannot change a protected metatable");
  122. lua_settop(L, 2);
  123. lua_setmetatable(L, 1);
  124. return 1;
  125. }
  126. static int luaB_rawequal (lua_State *L) {
  127. luaL_checkany(L, 1);
  128. luaL_checkany(L, 2);
  129. lua_pushboolean(L, lua_rawequal(L, 1, 2));
  130. return 1;
  131. }
  132. static int luaB_rawlen (lua_State *L) {
  133. int t = lua_type(L, 1);
  134. luaL_argexpected(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
  135. "table or string");
  136. lua_pushinteger(L, lua_rawlen(L, 1));
  137. return 1;
  138. }
  139. static int luaB_rawget (lua_State *L) {
  140. luaL_checktype(L, 1, LUA_TTABLE);
  141. luaL_checkany(L, 2);
  142. lua_settop(L, 2);
  143. lua_rawget(L, 1);
  144. return 1;
  145. }
  146. static int luaB_rawset (lua_State *L) {
  147. luaL_checktype(L, 1, LUA_TTABLE);
  148. luaL_checkany(L, 2);
  149. luaL_checkany(L, 3);
  150. lua_settop(L, 3);
  151. lua_rawset(L, 1);
  152. return 1;
  153. }
  154. static int pushmode (lua_State *L, int oldmode) {
  155. if (oldmode == -1)
  156. luaL_pushfail(L); /* invalid call to 'lua_gc' */
  157. else
  158. lua_pushstring(L, (oldmode == LUA_GCINC) ? "incremental"
  159. : "generational");
  160. return 1;
  161. }
  162. /*
  163. ** check whether call to 'lua_gc' was valid (not inside a finalizer)
  164. */
  165. #define checkvalres(res) { if (res == -1) break; }
  166. static int luaB_collectgarbage (lua_State *L) {
  167. static const char *const opts[] = {"stop", "restart", "collect",
  168. "count", "step", "setpause", "setstepmul",
  169. "isrunning", "generational", "incremental", NULL};
  170. static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
  171. LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
  172. LUA_GCISRUNNING, LUA_GCGEN, LUA_GCINC};
  173. int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
  174. switch (o) {
  175. case LUA_GCCOUNT: {
  176. int k = lua_gc(L, o);
  177. int b = lua_gc(L, LUA_GCCOUNTB);
  178. checkvalres(k);
  179. lua_pushnumber(L, (lua_Number)k + ((lua_Number)b/1024));
  180. return 1;
  181. }
  182. case LUA_GCSTEP: {
  183. int step = (int)luaL_optinteger(L, 2, 0);
  184. int res = lua_gc(L, o, step);
  185. checkvalres(res);
  186. lua_pushboolean(L, res);
  187. return 1;
  188. }
  189. case LUA_GCSETPAUSE:
  190. case LUA_GCSETSTEPMUL: {
  191. int p = (int)luaL_optinteger(L, 2, 0);
  192. int previous = lua_gc(L, o, p);
  193. checkvalres(previous);
  194. lua_pushinteger(L, previous);
  195. return 1;
  196. }
  197. case LUA_GCISRUNNING: {
  198. int res = lua_gc(L, o);
  199. checkvalres(res);
  200. lua_pushboolean(L, res);
  201. return 1;
  202. }
  203. case LUA_GCGEN: {
  204. int minormul = (int)luaL_optinteger(L, 2, 0);
  205. int majormul = (int)luaL_optinteger(L, 3, 0);
  206. return pushmode(L, lua_gc(L, o, minormul, majormul));
  207. }
  208. case LUA_GCINC: {
  209. int pause = (int)luaL_optinteger(L, 2, 0);
  210. int stepmul = (int)luaL_optinteger(L, 3, 0);
  211. int stepsize = (int)luaL_optinteger(L, 4, 0);
  212. return pushmode(L, lua_gc(L, o, pause, stepmul, stepsize));
  213. }
  214. default: {
  215. int res = lua_gc(L, o);
  216. checkvalres(res);
  217. lua_pushinteger(L, res);
  218. return 1;
  219. }
  220. }
  221. luaL_pushfail(L); /* invalid call (inside a finalizer) */
  222. return 1;
  223. }
  224. static int luaB_type (lua_State *L) {
  225. int t = lua_type(L, 1);
  226. luaL_argcheck(L, t != LUA_TNONE, 1, "value expected");
  227. lua_pushstring(L, lua_typename(L, t));
  228. return 1;
  229. }
  230. static int luaB_next (lua_State *L) {
  231. luaL_checktype(L, 1, LUA_TTABLE);
  232. lua_settop(L, 2); /* create a 2nd argument if there isn't one */
  233. if (lua_next(L, 1))
  234. return 2;
  235. else {
  236. lua_pushnil(L);
  237. return 1;
  238. }
  239. }
  240. static int pairscont (lua_State *L, int status, lua_KContext k) {
  241. (void)L; (void)status; (void)k; /* unused */
  242. return 3;
  243. }
  244. static int luaB_pairs (lua_State *L) {
  245. luaL_checkany(L, 1);
  246. if (luaL_getmetafield(L, 1, "__pairs") == LUA_TNIL) { /* no metamethod? */
  247. lua_pushcfunction(L, luaB_next); /* will return generator, */
  248. lua_pushvalue(L, 1); /* state, */
  249. lua_pushnil(L); /* and initial value */
  250. }
  251. else {
  252. lua_pushvalue(L, 1); /* argument 'self' to metamethod */
  253. lua_callk(L, 1, 3, 0, pairscont); /* get 3 values from metamethod */
  254. }
  255. return 3;
  256. }
  257. /*
  258. ** Traversal function for 'ipairs'
  259. */
  260. static int ipairsaux (lua_State *L) {
  261. lua_Integer i = luaL_checkinteger(L, 2);
  262. i = luaL_intop(+, i, 1);
  263. lua_pushinteger(L, i);
  264. return (lua_geti(L, 1, i) == LUA_TNIL) ? 1 : 2;
  265. }
  266. /*
  267. ** 'ipairs' function. Returns 'ipairsaux', given "table", 0.
  268. ** (The given "table" may not be a table.)
  269. */
  270. static int luaB_ipairs (lua_State *L) {
  271. luaL_checkany(L, 1);
  272. lua_pushcfunction(L, ipairsaux); /* iteration function */
  273. lua_pushvalue(L, 1); /* state */
  274. lua_pushinteger(L, 0); /* initial value */
  275. return 3;
  276. }
  277. static int load_aux (lua_State *L, int status, int envidx) {
  278. if (l_likely(status == LUA_OK)) {
  279. if (envidx != 0) { /* 'env' parameter? */
  280. lua_pushvalue(L, envidx); /* environment for loaded function */
  281. if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */
  282. lua_pop(L, 1); /* remove 'env' if not used by previous call */
  283. }
  284. return 1;
  285. }
  286. else { /* error (message is on top of the stack) */
  287. luaL_pushfail(L);
  288. lua_insert(L, -2); /* put before error message */
  289. return 2; /* return fail plus error message */
  290. }
  291. }
  292. static int luaB_loadfile (lua_State *L) {
  293. const char *fname = luaL_optstring(L, 1, NULL);
  294. const char *mode = luaL_optstring(L, 2, NULL);
  295. int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */
  296. int status = luaL_loadfilex(L, fname, mode);
  297. return load_aux(L, status, env);
  298. }
  299. /*
  300. ** {======================================================
  301. ** Generic Read function
  302. ** =======================================================
  303. */
  304. /*
  305. ** reserved slot, above all arguments, to hold a copy of the returned
  306. ** string to avoid it being collected while parsed. 'load' has four
  307. ** optional arguments (chunk, source name, mode, and environment).
  308. */
  309. #define RESERVEDSLOT 5
  310. /*
  311. ** Reader for generic 'load' function: 'lua_load' uses the
  312. ** stack for internal stuff, so the reader cannot change the
  313. ** stack top. Instead, it keeps its resulting string in a
  314. ** reserved slot inside the stack.
  315. */
  316. static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
  317. (void)(ud); /* not used */
  318. luaL_checkstack(L, 2, "too many nested functions");
  319. lua_pushvalue(L, 1); /* get function */
  320. lua_call(L, 0, 1); /* call it */
  321. if (lua_isnil(L, -1)) {
  322. lua_pop(L, 1); /* pop result */
  323. *size = 0;
  324. return NULL;
  325. }
  326. else if (l_unlikely(!lua_isstring(L, -1)))
  327. luaL_error(L, "reader function must return a string");
  328. lua_replace(L, RESERVEDSLOT); /* save string in reserved slot */
  329. return lua_tolstring(L, RESERVEDSLOT, size);
  330. }
  331. static int luaB_load (lua_State *L) {
  332. int status;
  333. size_t l;
  334. const char *s = lua_tolstring(L, 1, &l);
  335. const char *mode = luaL_optstring(L, 3, "bt");
  336. int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */
  337. if (s != NULL) { /* loading a string? */
  338. const char *chunkname = luaL_optstring(L, 2, s);
  339. status = luaL_loadbufferx(L, s, l, chunkname, mode);
  340. }
  341. else { /* loading from a reader function */
  342. const char *chunkname = luaL_optstring(L, 2, "=(load)");
  343. luaL_checktype(L, 1, LUA_TFUNCTION);
  344. lua_settop(L, RESERVEDSLOT); /* create reserved slot */
  345. status = lua_load(L, generic_reader, NULL, chunkname, mode);
  346. }
  347. return load_aux(L, status, env);
  348. }
  349. /* }====================================================== */
  350. static int dofilecont (lua_State *L, int d1, lua_KContext d2) {
  351. (void)d1; (void)d2; /* only to match 'lua_Kfunction' prototype */
  352. return lua_gettop(L) - 1;
  353. }
  354. static int luaB_dofile (lua_State *L) {
  355. const char *fname = luaL_optstring(L, 1, NULL);
  356. lua_settop(L, 1);
  357. if (l_unlikely(luaL_loadfile(L, fname) != LUA_OK))
  358. return lua_error(L);
  359. lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
  360. return dofilecont(L, 0, 0);
  361. }
  362. static int luaB_assert (lua_State *L) {
  363. if (l_likely(lua_toboolean(L, 1))) /* condition is true? */
  364. return lua_gettop(L); /* return all arguments */
  365. else { /* error */
  366. luaL_checkany(L, 1); /* there must be a condition */
  367. lua_remove(L, 1); /* remove it */
  368. lua_pushliteral(L, "assertion failed!"); /* default message */
  369. lua_settop(L, 1); /* leave only message (default if no other one) */
  370. return luaB_error(L); /* call 'error' */
  371. }
  372. }
  373. static int luaB_select (lua_State *L) {
  374. int n = lua_gettop(L);
  375. if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
  376. lua_pushinteger(L, n-1);
  377. return 1;
  378. }
  379. else {
  380. lua_Integer i = luaL_checkinteger(L, 1);
  381. if (i < 0) i = n + i;
  382. else if (i > n) i = n;
  383. luaL_argcheck(L, 1 <= i, 1, "index out of range");
  384. return n - (int)i;
  385. }
  386. }
  387. /*
  388. ** Continuation function for 'pcall' and 'xpcall'. Both functions
  389. ** already pushed a 'true' before doing the call, so in case of success
  390. ** 'finishpcall' only has to return everything in the stack minus
  391. ** 'extra' values (where 'extra' is exactly the number of items to be
  392. ** ignored).
  393. */
  394. static int finishpcall (lua_State *L, int status, lua_KContext extra) {
  395. if (l_unlikely(status != LUA_OK && status != LUA_YIELD)) { /* error? */
  396. lua_pushboolean(L, 0); /* first result (false) */
  397. lua_pushvalue(L, -2); /* error message */
  398. return 2; /* return false, msg */
  399. }
  400. else
  401. return lua_gettop(L) - (int)extra; /* return all results */
  402. }
  403. static int luaB_pcall (lua_State *L) {
  404. int status;
  405. luaL_checkany(L, 1);
  406. lua_pushboolean(L, 1); /* first result if no errors */
  407. lua_insert(L, 1); /* put it in place */
  408. status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
  409. return finishpcall(L, status, 0);
  410. }
  411. /*
  412. ** Do a protected call with error handling. After 'lua_rotate', the
  413. ** stack will have <f, err, true, f, [args...]>; so, the function passes
  414. ** 2 to 'finishpcall' to skip the 2 first values when returning results.
  415. */
  416. static int luaB_xpcall (lua_State *L) {
  417. int status;
  418. int n = lua_gettop(L);
  419. luaL_checktype(L, 2, LUA_TFUNCTION); /* check error function */
  420. lua_pushboolean(L, 1); /* first result */
  421. lua_pushvalue(L, 1); /* function */
  422. lua_rotate(L, 3, 2); /* move them below function's arguments */
  423. status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
  424. return finishpcall(L, status, 2);
  425. }
  426. static int luaB_tostring (lua_State *L) {
  427. luaL_checkany(L, 1);
  428. luaL_tolstring(L, 1, NULL);
  429. return 1;
  430. }
  431. static const luaL_Reg base_funcs[] = {
  432. {"assert", luaB_assert},
  433. {"collectgarbage", luaB_collectgarbage},
  434. {"dofile", luaB_dofile},
  435. {"error", luaB_error},
  436. {"getmetatable", luaB_getmetatable},
  437. {"ipairs", luaB_ipairs},
  438. {"loadfile", luaB_loadfile},
  439. {"load", luaB_load},
  440. {"next", luaB_next},
  441. {"pairs", luaB_pairs},
  442. {"pcall", luaB_pcall},
  443. {"print", luaB_print},
  444. {"warn", luaB_warn},
  445. {"rawequal", luaB_rawequal},
  446. {"rawlen", luaB_rawlen},
  447. {"rawget", luaB_rawget},
  448. {"rawset", luaB_rawset},
  449. {"select", luaB_select},
  450. {"setmetatable", luaB_setmetatable},
  451. {"tonumber", luaB_tonumber},
  452. {"tostring", luaB_tostring},
  453. {"type", luaB_type},
  454. {"xpcall", luaB_xpcall},
  455. /* placeholders */
  456. {LUA_GNAME, NULL},
  457. {"_VERSION", NULL},
  458. {NULL, NULL}
  459. };
  460. LUAMOD_API int luaopen_base (lua_State *L) {
  461. /* open lib into global table */
  462. lua_pushglobaltable(L);
  463. luaL_setfuncs(L, base_funcs, 0);
  464. /* set global _G */
  465. lua_pushvalue(L, -1);
  466. lua_setfield(L, -2, LUA_GNAME);
  467. /* set global _VERSION */
  468. lua_pushliteral(L, LUA_VERSION);
  469. lua_setfield(L, -2, "_VERSION");
  470. return 1;
  471. }