1 /*
2 ** $Id: lbaselib.c,v 1.314.1.1 2017/04/19 17:39:34 roberto Exp $
3 ** Basic library
4 ** See Copyright Notice in lua.h
5 */
6
7 #define lbaselib_c
8 #define LUA_LIB
9
10 #include "lprefix.h"
11
12
13 #include <ctype.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17
18 #include "lua.h"
19
20 #include "lauxlib.h"
21 #include "lualib.h"
22
23
luaB_print(lua_State * L)24 static int luaB_print (lua_State *L) {
25 int n = lua_gettop(L); /* number of arguments */
26 int i;
27 lua_getglobal(L, "tostring");
28 for (i=1; i<=n; i++) {
29 const char *s;
30 size_t l;
31 lua_pushvalue(L, -1); /* function to be called */
32 lua_pushvalue(L, i); /* value to print */
33 lua_call(L, 1, 1);
34 s = lua_tolstring(L, -1, &l); /* get result */
35 if (s == NULL)
36 return luaL_error(L, "'tostring' must return a string to 'print'");
37 if (i>1) lua_writestring("\t", 1);
38 lua_writestring(s, l);
39 lua_pop(L, 1); /* pop result */
40 }
41 lua_writeline();
42 return 0;
43 }
44
45
46 #define SPACECHARS " \f\n\r\t\v"
47
b_str2int(const char * s,int base,lua_Integer * pn)48 static const char *b_str2int (const char *s, int base, lua_Integer *pn) {
49 lua_Unsigned n = 0;
50 int neg = 0;
51 s += strspn(s, SPACECHARS); /* skip initial spaces */
52 if (*s == '-') { s++; neg = 1; } /* handle signal */
53 else if (*s == '+') s++;
54 if (!isalnum((unsigned char)*s)) /* no digit? */
55 return NULL;
56 do {
57 int digit = (isdigit((unsigned char)*s)) ? *s - '0'
58 : (toupper((unsigned char)*s) - 'A') + 10;
59 if (digit >= base) return NULL; /* invalid numeral */
60 n = n * base + digit;
61 s++;
62 } while (isalnum((unsigned char)*s));
63 s += strspn(s, SPACECHARS); /* skip trailing spaces */
64 *pn = (lua_Integer)((neg) ? (0u - n) : n);
65 return s;
66 }
67
68
luaB_tonumber(lua_State * L)69 static int luaB_tonumber (lua_State *L) {
70 if (lua_isnoneornil(L, 2)) { /* standard conversion? */
71 luaL_checkany(L, 1);
72 if (lua_type(L, 1) == LUA_TNUMBER) { /* already a number? */
73 lua_settop(L, 1); /* yes; return it */
74 return 1;
75 }
76 else {
77 size_t l;
78 const char *s = lua_tolstring(L, 1, &l);
79 if (s != NULL && lua_stringtonumber(L, s) == l + 1)
80 return 1; /* successful conversion to number */
81 /* else not a number */
82 }
83 }
84 else {
85 size_t l;
86 const char *s;
87 lua_Integer n = 0; /* to avoid warnings */
88 lua_Integer base = luaL_checkinteger(L, 2);
89 luaL_checktype(L, 1, LUA_TSTRING); /* no numbers as strings */
90 s = lua_tolstring(L, 1, &l);
91 luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
92 if (b_str2int(s, (int)base, &n) == s + l) {
93 lua_pushinteger(L, n);
94 return 1;
95 } /* else not a number */
96 } /* else not a number */
97 lua_pushnil(L); /* not a number */
98 return 1;
99 }
100
101
luaB_error(lua_State * L)102 static int luaB_error (lua_State *L) {
103 int level = (int)luaL_optinteger(L, 2, 1);
104 lua_settop(L, 1);
105 if (lua_type(L, 1) == LUA_TSTRING && level > 0) {
106 luaL_where(L, level); /* add extra information */
107 lua_pushvalue(L, 1);
108 lua_concat(L, 2);
109 }
110 return lua_error(L);
111 }
112
113
luaB_getmetatable(lua_State * L)114 static int luaB_getmetatable (lua_State *L) {
115 luaL_checkany(L, 1);
116 if (!lua_getmetatable(L, 1)) {
117 lua_pushnil(L);
118 return 1; /* no metatable */
119 }
120 luaL_getmetafield(L, 1, "__metatable");
121 return 1; /* returns either __metatable field (if present) or metatable */
122 }
123
124
luaB_setmetatable(lua_State * L)125 static int luaB_setmetatable (lua_State *L) {
126 int t = lua_type(L, 2);
127 luaL_checktype(L, 1, LUA_TTABLE);
128 luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
129 "nil or table expected");
130 if (luaL_getmetafield(L, 1, "__metatable") != LUA_TNIL)
131 return luaL_error(L, "cannot change a protected metatable");
132 lua_settop(L, 2);
133 lua_setmetatable(L, 1);
134 return 1;
135 }
136
137
luaB_rawequal(lua_State * L)138 static int luaB_rawequal (lua_State *L) {
139 luaL_checkany(L, 1);
140 luaL_checkany(L, 2);
141 lua_pushboolean(L, lua_rawequal(L, 1, 2));
142 return 1;
143 }
144
145
luaB_rawlen(lua_State * L)146 static int luaB_rawlen (lua_State *L) {
147 int t = lua_type(L, 1);
148 luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
149 "table or string expected");
150 lua_pushinteger(L, lua_rawlen(L, 1));
151 return 1;
152 }
153
154
luaB_rawget(lua_State * L)155 static int luaB_rawget (lua_State *L) {
156 luaL_checktype(L, 1, LUA_TTABLE);
157 luaL_checkany(L, 2);
158 lua_settop(L, 2);
159 lua_rawget(L, 1);
160 return 1;
161 }
162
luaB_rawset(lua_State * L)163 static int luaB_rawset (lua_State *L) {
164 luaL_checktype(L, 1, LUA_TTABLE);
165 luaL_checkany(L, 2);
166 luaL_checkany(L, 3);
167 lua_settop(L, 3);
168 lua_rawset(L, 1);
169 return 1;
170 }
171
172
luaB_collectgarbage(lua_State * L)173 static int luaB_collectgarbage (lua_State *L) {
174 static const char *const opts[] = {"stop", "restart", "collect",
175 "count", "step", "setpause", "setstepmul",
176 "isrunning", NULL};
177 static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
178 LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
179 LUA_GCISRUNNING};
180 int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
181 int ex = (int)luaL_optinteger(L, 2, 0);
182 int res = lua_gc(L, o, ex);
183 switch (o) {
184 case LUA_GCCOUNT: {
185 int b = lua_gc(L, LUA_GCCOUNTB, 0);
186 lua_pushnumber(L, (lua_Number)res + ((lua_Number)b/1024));
187 return 1;
188 }
189 case LUA_GCSTEP: case LUA_GCISRUNNING: {
190 lua_pushboolean(L, res);
191 return 1;
192 }
193 default: {
194 lua_pushinteger(L, res);
195 return 1;
196 }
197 }
198 }
199
200
luaB_type(lua_State * L)201 static int luaB_type (lua_State *L) {
202 int t = lua_type(L, 1);
203 luaL_argcheck(L, t != LUA_TNONE, 1, "value expected");
204 lua_pushstring(L, lua_typename(L, t));
205 return 1;
206 }
207
208
pairsmeta(lua_State * L,const char * method,int iszero,lua_CFunction iter)209 static int pairsmeta (lua_State *L, const char *method, int iszero,
210 lua_CFunction iter) {
211 luaL_checkany(L, 1);
212 if (luaL_getmetafield(L, 1, method) == LUA_TNIL) { /* no metamethod? */
213 lua_pushcfunction(L, iter); /* will return generator, */
214 lua_pushvalue(L, 1); /* state, */
215 if (iszero) lua_pushinteger(L, 0); /* and initial value */
216 else lua_pushnil(L);
217 }
218 else {
219 lua_pushvalue(L, 1); /* argument 'self' to metamethod */
220 lua_call(L, 1, 3); /* get 3 values from metamethod */
221 }
222 return 3;
223 }
224
225
luaB_next(lua_State * L)226 static int luaB_next (lua_State *L) {
227 luaL_checktype(L, 1, LUA_TTABLE);
228 lua_settop(L, 2); /* create a 2nd argument if there isn't one */
229 if (lua_next(L, 1))
230 return 2;
231 else {
232 lua_pushnil(L);
233 return 1;
234 }
235 }
236
237
luaB_pairs(lua_State * L)238 static int luaB_pairs (lua_State *L) {
239 return pairsmeta(L, "__pairs", 0, luaB_next);
240 }
241
242
243 /*
244 ** Traversal function for 'ipairs'
245 */
ipairsaux(lua_State * L)246 static int ipairsaux (lua_State *L) {
247 lua_Integer i = luaL_checkinteger(L, 2) + 1;
248 lua_pushinteger(L, i);
249 return (lua_geti(L, 1, i) == LUA_TNIL) ? 1 : 2;
250 }
251
252
253 /*
254 ** 'ipairs' function. Returns 'ipairsaux', given "table", 0.
255 ** (The given "table" may not be a table.)
256 */
luaB_ipairs(lua_State * L)257 static int luaB_ipairs (lua_State *L) {
258 #if defined(LUA_COMPAT_IPAIRS)
259 return pairsmeta(L, "__ipairs", 1, ipairsaux);
260 #else
261 luaL_checkany(L, 1);
262 lua_pushcfunction(L, ipairsaux); /* iteration function */
263 lua_pushvalue(L, 1); /* state */
264 lua_pushinteger(L, 0); /* initial value */
265 return 3;
266 #endif
267 }
268
269
load_aux(lua_State * L,int status,int envidx)270 static int load_aux (lua_State *L, int status, int envidx) {
271 if (status == LUA_OK) {
272 if (envidx != 0) { /* 'env' parameter? */
273 lua_pushvalue(L, envidx); /* environment for loaded function */
274 if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */
275 lua_pop(L, 1); /* remove 'env' if not used by previous call */
276 }
277 return 1;
278 }
279 else { /* error (message is on top of the stack) */
280 lua_pushnil(L);
281 lua_insert(L, -2); /* put before error message */
282 return 2; /* return nil plus error message */
283 }
284 }
285
286
luaB_loadfile(lua_State * L)287 static int luaB_loadfile (lua_State *L) {
288 const char *fname = luaL_optstring(L, 1, NULL);
289 const char *mode = luaL_optstring(L, 2, NULL);
290 int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */
291 int status = luaL_loadfilex(L, fname, mode);
292 return load_aux(L, status, env);
293 }
294
295
296 /*
297 ** {======================================================
298 ** Generic Read function
299 ** =======================================================
300 */
301
302
303 /*
304 ** reserved slot, above all arguments, to hold a copy of the returned
305 ** string to avoid it being collected while parsed. 'load' has four
306 ** optional arguments (chunk, source name, mode, and environment).
307 */
308 #define RESERVEDSLOT 5
309
310
311 /*
312 ** Reader for generic 'load' function: 'lua_load' uses the
313 ** stack for internal stuff, so the reader cannot change the
314 ** stack top. Instead, it keeps its resulting string in a
315 ** reserved slot inside the stack.
316 */
generic_reader(lua_State * L,void * ud,size_t * size)317 static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
318 (void)(ud); /* not used */
319 luaL_checkstack(L, 2, "too many nested functions");
320 lua_pushvalue(L, 1); /* get function */
321 lua_call(L, 0, 1); /* call it */
322 if (lua_isnil(L, -1)) {
323 lua_pop(L, 1); /* pop result */
324 *size = 0;
325 return NULL;
326 }
327 else if (!lua_isstring(L, -1))
328 luaL_error(L, "reader function must return a string");
329 lua_replace(L, RESERVEDSLOT); /* save string in reserved slot */
330 return lua_tolstring(L, RESERVEDSLOT, size);
331 }
332
333
luaB_load(lua_State * L)334 static int luaB_load (lua_State *L) {
335 int status;
336 size_t l;
337 const char *s = lua_tolstring(L, 1, &l);
338 const char *mode = luaL_optstring(L, 3, "bt");
339 int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */
340 if (s != NULL) { /* loading a string? */
341 const char *chunkname = luaL_optstring(L, 2, s);
342 status = luaL_loadbufferx(L, s, l, chunkname, mode);
343 }
344 else { /* loading from a reader function */
345 const char *chunkname = luaL_optstring(L, 2, "=(load)");
346 luaL_checktype(L, 1, LUA_TFUNCTION);
347 lua_settop(L, RESERVEDSLOT); /* create reserved slot */
348 status = lua_load(L, generic_reader, NULL, chunkname, mode);
349 }
350 return load_aux(L, status, env);
351 }
352
353 /* }====================================================== */
354
355
dofilecont(lua_State * L,int d1,lua_KContext d2)356 static int dofilecont (lua_State *L, int d1, lua_KContext d2) {
357 (void)d1; (void)d2; /* only to match 'lua_Kfunction' prototype */
358 return lua_gettop(L) - 1;
359 }
360
361
luaB_dofile(lua_State * L)362 static int luaB_dofile (lua_State *L) {
363 const char *fname = luaL_optstring(L, 1, NULL);
364 lua_settop(L, 1);
365 if (luaL_loadfile(L, fname) != LUA_OK)
366 return lua_error(L);
367 lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
368 return dofilecont(L, 0, 0);
369 }
370
371
luaB_assert(lua_State * L)372 static int luaB_assert (lua_State *L) {
373 if (lua_toboolean(L, 1)) /* condition is true? */
374 return lua_gettop(L); /* return all arguments */
375 else { /* error */
376 luaL_checkany(L, 1); /* there must be a condition */
377 lua_remove(L, 1); /* remove it */
378 lua_pushliteral(L, "assertion failed!"); /* default message */
379 lua_settop(L, 1); /* leave only message (default if no other one) */
380 return luaB_error(L); /* call 'error' */
381 }
382 }
383
384
luaB_select(lua_State * L)385 static int luaB_select (lua_State *L) {
386 int n = lua_gettop(L);
387 if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
388 lua_pushinteger(L, n-1);
389 return 1;
390 }
391 else {
392 lua_Integer i = luaL_checkinteger(L, 1);
393 if (i < 0) i = n + i;
394 else if (i > n) i = n;
395 luaL_argcheck(L, 1 <= i, 1, "index out of range");
396 return n - (int)i;
397 }
398 }
399
400
401 /*
402 ** Continuation function for 'pcall' and 'xpcall'. Both functions
403 ** already pushed a 'true' before doing the call, so in case of success
404 ** 'finishpcall' only has to return everything in the stack minus
405 ** 'extra' values (where 'extra' is exactly the number of items to be
406 ** ignored).
407 */
finishpcall(lua_State * L,int status,lua_KContext extra)408 static int finishpcall (lua_State *L, int status, lua_KContext extra) {
409 if (status != LUA_OK && status != LUA_YIELD) { /* error? */
410 lua_pushboolean(L, 0); /* first result (false) */
411 lua_pushvalue(L, -2); /* error message */
412 return 2; /* return false, msg */
413 }
414 else
415 return lua_gettop(L) - (int)extra; /* return all results */
416 }
417
418
luaB_pcall(lua_State * L)419 static int luaB_pcall (lua_State *L) {
420 int status;
421 luaL_checkany(L, 1);
422 lua_pushboolean(L, 1); /* first result if no errors */
423 lua_insert(L, 1); /* put it in place */
424 status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
425 return finishpcall(L, status, 0);
426 }
427
428
429 /*
430 ** Do a protected call with error handling. After 'lua_rotate', the
431 ** stack will have <f, err, true, f, [args...]>; so, the function passes
432 ** 2 to 'finishpcall' to skip the 2 first values when returning results.
433 */
luaB_xpcall(lua_State * L)434 static int luaB_xpcall (lua_State *L) {
435 int status;
436 int n = lua_gettop(L);
437 luaL_checktype(L, 2, LUA_TFUNCTION); /* check error function */
438 lua_pushboolean(L, 1); /* first result */
439 lua_pushvalue(L, 1); /* function */
440 lua_rotate(L, 3, 2); /* move them below function's arguments */
441 status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
442 return finishpcall(L, status, 2);
443 }
444
445
luaB_tostring(lua_State * L)446 static int luaB_tostring (lua_State *L) {
447 luaL_checkany(L, 1);
448 luaL_tolstring(L, 1, NULL);
449 return 1;
450 }
451
452
453 static const luaL_Reg base_funcs[] = {
454 {"assert", luaB_assert},
455 {"collectgarbage", luaB_collectgarbage},
456 {"dofile", luaB_dofile},
457 {"error", luaB_error},
458 {"getmetatable", luaB_getmetatable},
459 {"ipairs", luaB_ipairs},
460 {"loadfile", luaB_loadfile},
461 {"load", luaB_load},
462 #if defined(LUA_COMPAT_LOADSTRING)
463 {"loadstring", luaB_load},
464 #endif
465 {"next", luaB_next},
466 {"pairs", luaB_pairs},
467 {"pcall", luaB_pcall},
468 {"print", luaB_print},
469 {"rawequal", luaB_rawequal},
470 {"rawlen", luaB_rawlen},
471 {"rawget", luaB_rawget},
472 {"rawset", luaB_rawset},
473 {"select", luaB_select},
474 {"setmetatable", luaB_setmetatable},
475 {"tonumber", luaB_tonumber},
476 {"tostring", luaB_tostring},
477 {"type", luaB_type},
478 {"xpcall", luaB_xpcall},
479 /* placeholders */
480 {"_G", NULL},
481 {"_VERSION", NULL},
482 {NULL, NULL}
483 };
484
485
luaopen_base(lua_State * L)486 LUAMOD_API int luaopen_base (lua_State *L) {
487 /* open lib into global table */
488 lua_pushglobaltable(L);
489 luaL_setfuncs(L, base_funcs, 0);
490 /* set global _G */
491 lua_pushvalue(L, -1);
492 lua_setfield(L, -2, "_G");
493 /* set global _VERSION */
494 lua_pushliteral(L, LUA_VERSION);
495 lua_setfield(L, -2, "_VERSION");
496 return 1;
497 }
498
499