1 /* $NetBSD: lbaselib.c,v 1.5 2015/10/08 13:21:00 mbalmer Exp $ */
2
3 /*
4 ** Id: lbaselib.c,v 1.310 2015/03/28 19:14:47 roberto Exp
5 ** Basic library
6 ** See Copyright Notice in lua.h
7 */
8
9 #define lbaselib_c
10 #define LUA_LIB
11
12 #include "lprefix.h"
13
14
15 #ifndef _KERNEL
16 #include <ctype.h>
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <string.h>
20 #endif
21
22 #include "lua.h"
23
24 #include "lauxlib.h"
25 #include "lualib.h"
26
27
luaB_print(lua_State * L)28 static int luaB_print (lua_State *L) {
29 int n = lua_gettop(L); /* number of arguments */
30 int i;
31 lua_getglobal(L, "tostring");
32 for (i=1; i<=n; i++) {
33 const char *s;
34 size_t l;
35 lua_pushvalue(L, -1); /* function to be called */
36 lua_pushvalue(L, i); /* value to print */
37 lua_call(L, 1, 1);
38 s = lua_tolstring(L, -1, &l); /* get result */
39 if (s == NULL)
40 return luaL_error(L, "'tostring' must return a string to 'print'");
41 if (i>1) lua_writestring("\t", 1);
42 lua_writestring(s, l);
43 lua_pop(L, 1); /* pop result */
44 }
45 lua_writeline();
46 return 0;
47 }
48
49
50 #define SPACECHARS " \f\n\r\t\v"
51
b_str2int(const char * s,int base,lua_Integer * pn)52 static const char *b_str2int (const char *s, int base, lua_Integer *pn) {
53 lua_Unsigned n = 0;
54 int neg = 0;
55 s += strspn(s, SPACECHARS); /* skip initial spaces */
56 if (*s == '-') { s++; neg = 1; } /* handle signal */
57 else if (*s == '+') s++;
58 if (!isalnum((unsigned char)*s)) /* no digit? */
59 return NULL;
60 do {
61 int digit = (isdigit((unsigned char)*s)) ? *s - '0'
62 : (toupper((unsigned char)*s) - 'A') + 10;
63 if (digit >= base) return NULL; /* invalid numeral */
64 n = n * base + digit;
65 s++;
66 } while (isalnum((unsigned char)*s));
67 s += strspn(s, SPACECHARS); /* skip trailing spaces */
68 *pn = (lua_Integer)((neg) ? (0u - n) : n);
69 return s;
70 }
71
72
luaB_tonumber(lua_State * L)73 static int luaB_tonumber (lua_State *L) {
74 if (lua_isnoneornil(L, 2)) { /* standard conversion? */
75 luaL_checkany(L, 1);
76 if (lua_type(L, 1) == LUA_TNUMBER) { /* already a number? */
77 lua_settop(L, 1); /* yes; return it */
78 return 1;
79 }
80 else {
81 size_t l;
82 const char *s = lua_tolstring(L, 1, &l);
83 if (s != NULL && lua_stringtonumber(L, s) == l + 1)
84 return 1; /* successful conversion to number */
85 /* else not a number */
86 }
87 }
88 else {
89 size_t l;
90 const char *s;
91 lua_Integer n = 0; /* to avoid warnings */
92 lua_Integer base = luaL_checkinteger(L, 2);
93 luaL_checktype(L, 1, LUA_TSTRING); /* before 'luaL_checklstring'! */
94 s = luaL_checklstring(L, 1, &l);
95 luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
96 if (b_str2int(s, (int)base, &n) == s + l) {
97 lua_pushinteger(L, n);
98 return 1;
99 } /* else not a number */
100 } /* else not a number */
101 lua_pushnil(L); /* not a number */
102 return 1;
103 }
104
105
luaB_error(lua_State * L)106 static int luaB_error (lua_State *L) {
107 int level = (int)luaL_optinteger(L, 2, 1);
108 lua_settop(L, 1);
109 if (lua_isstring(L, 1) && level > 0) { /* add extra information? */
110 luaL_where(L, level);
111 lua_pushvalue(L, 1);
112 lua_concat(L, 2);
113 }
114 return lua_error(L);
115 }
116
117
luaB_getmetatable(lua_State * L)118 static int luaB_getmetatable (lua_State *L) {
119 luaL_checkany(L, 1);
120 if (!lua_getmetatable(L, 1)) {
121 lua_pushnil(L);
122 return 1; /* no metatable */
123 }
124 luaL_getmetafield(L, 1, "__metatable");
125 return 1; /* returns either __metatable field (if present) or metatable */
126 }
127
128
luaB_setmetatable(lua_State * L)129 static int luaB_setmetatable (lua_State *L) {
130 int t = lua_type(L, 2);
131 luaL_checktype(L, 1, LUA_TTABLE);
132 luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
133 "nil or table expected");
134 if (luaL_getmetafield(L, 1, "__metatable") != LUA_TNIL)
135 return luaL_error(L, "cannot change a protected metatable");
136 lua_settop(L, 2);
137 lua_setmetatable(L, 1);
138 return 1;
139 }
140
141
luaB_rawequal(lua_State * L)142 static int luaB_rawequal (lua_State *L) {
143 luaL_checkany(L, 1);
144 luaL_checkany(L, 2);
145 lua_pushboolean(L, lua_rawequal(L, 1, 2));
146 return 1;
147 }
148
149
luaB_rawlen(lua_State * L)150 static int luaB_rawlen (lua_State *L) {
151 int t = lua_type(L, 1);
152 luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
153 "table or string expected");
154 lua_pushinteger(L, lua_rawlen(L, 1));
155 return 1;
156 }
157
158
luaB_rawget(lua_State * L)159 static int luaB_rawget (lua_State *L) {
160 luaL_checktype(L, 1, LUA_TTABLE);
161 luaL_checkany(L, 2);
162 lua_settop(L, 2);
163 lua_rawget(L, 1);
164 return 1;
165 }
166
luaB_rawset(lua_State * L)167 static int luaB_rawset (lua_State *L) {
168 luaL_checktype(L, 1, LUA_TTABLE);
169 luaL_checkany(L, 2);
170 luaL_checkany(L, 3);
171 lua_settop(L, 3);
172 lua_rawset(L, 1);
173 return 1;
174 }
175
176
luaB_collectgarbage(lua_State * L)177 static int luaB_collectgarbage (lua_State *L) {
178 static const char *const opts[] = {"stop", "restart", "collect",
179 "count", "step", "setpause", "setstepmul",
180 "isrunning", NULL};
181 static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
182 LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
183 LUA_GCISRUNNING};
184 int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
185 int ex = (int)luaL_optinteger(L, 2, 0);
186 int res = lua_gc(L, o, ex);
187 switch (o) {
188 case LUA_GCCOUNT: {
189 int b = lua_gc(L, LUA_GCCOUNTB, 0);
190 lua_pushnumber(L, (lua_Number)res + ((lua_Number)b/1024));
191 return 1;
192 }
193 case LUA_GCSTEP: case LUA_GCISRUNNING: {
194 lua_pushboolean(L, res);
195 return 1;
196 }
197 default: {
198 lua_pushinteger(L, res);
199 return 1;
200 }
201 }
202 }
203
204
205 /*
206 ** This function has all type names as upvalues, to maximize performance.
207 */
luaB_type(lua_State * L)208 static int luaB_type (lua_State *L) {
209 luaL_checkany(L, 1);
210 lua_pushvalue(L, lua_upvalueindex(lua_type(L, 1) + 1));
211 return 1;
212 }
213
214
pairsmeta(lua_State * L,const char * method,int iszero,lua_CFunction iter)215 static int pairsmeta (lua_State *L, const char *method, int iszero,
216 lua_CFunction iter) {
217 if (luaL_getmetafield(L, 1, method) == LUA_TNIL) { /* no metamethod? */
218 luaL_checktype(L, 1, LUA_TTABLE); /* argument must be a table */
219 lua_pushcfunction(L, iter); /* will return generator, */
220 lua_pushvalue(L, 1); /* state, */
221 if (iszero) lua_pushinteger(L, 0); /* and initial value */
222 else lua_pushnil(L);
223 }
224 else {
225 lua_pushvalue(L, 1); /* argument 'self' to metamethod */
226 lua_call(L, 1, 3); /* get 3 values from metamethod */
227 }
228 return 3;
229 }
230
231
luaB_next(lua_State * L)232 static int luaB_next (lua_State *L) {
233 luaL_checktype(L, 1, LUA_TTABLE);
234 lua_settop(L, 2); /* create a 2nd argument if there isn't one */
235 if (lua_next(L, 1))
236 return 2;
237 else {
238 lua_pushnil(L);
239 return 1;
240 }
241 }
242
243
luaB_pairs(lua_State * L)244 static int luaB_pairs (lua_State *L) {
245 return pairsmeta(L, "__pairs", 0, luaB_next);
246 }
247
248
249 /*
250 ** Traversal function for 'ipairs' for raw tables
251 */
ipairsaux_raw(lua_State * L)252 static int ipairsaux_raw (lua_State *L) {
253 lua_Integer i = luaL_checkinteger(L, 2) + 1;
254 luaL_checktype(L, 1, LUA_TTABLE);
255 lua_pushinteger(L, i);
256 return (lua_rawgeti(L, 1, i) == LUA_TNIL) ? 1 : 2;
257 }
258
259
260 /*
261 ** Traversal function for 'ipairs' for tables with metamethods
262 */
ipairsaux(lua_State * L)263 static int ipairsaux (lua_State *L) {
264 lua_Integer i = luaL_checkinteger(L, 2) + 1;
265 lua_pushinteger(L, i);
266 return (lua_geti(L, 1, i) == LUA_TNIL) ? 1 : 2;
267 }
268
269
270 /*
271 ** This function will use either 'ipairsaux' or 'ipairsaux_raw' to
272 ** traverse a table, depending on whether the table has metamethods
273 ** that can affect the traversal.
274 */
luaB_ipairs(lua_State * L)275 static int luaB_ipairs (lua_State *L) {
276 lua_CFunction iter = (luaL_getmetafield(L, 1, "__index") != LUA_TNIL)
277 ? ipairsaux : ipairsaux_raw;
278 #if defined(LUA_COMPAT_IPAIRS)
279 return pairsmeta(L, "__ipairs", 1, iter);
280 #else
281 luaL_checkany(L, 1);
282 lua_pushcfunction(L, iter); /* iteration function */
283 lua_pushvalue(L, 1); /* state */
284 lua_pushinteger(L, 0); /* initial value */
285 return 3;
286 #endif
287 }
288
289
load_aux(lua_State * L,int status,int envidx)290 static int load_aux (lua_State *L, int status, int envidx) {
291 if (status == LUA_OK) {
292 if (envidx != 0) { /* 'env' parameter? */
293 lua_pushvalue(L, envidx); /* environment for loaded function */
294 if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */
295 lua_pop(L, 1); /* remove 'env' if not used by previous call */
296 }
297 return 1;
298 }
299 else { /* error (message is on top of the stack) */
300 lua_pushnil(L);
301 lua_insert(L, -2); /* put before error message */
302 return 2; /* return nil plus error message */
303 }
304 }
305
306
307 #ifndef _KERNEL
luaB_loadfile(lua_State * L)308 static int luaB_loadfile (lua_State *L) {
309 const char *fname = luaL_optstring(L, 1, NULL);
310 const char *mode = luaL_optstring(L, 2, NULL);
311 int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */
312 int status = luaL_loadfilex(L, fname, mode);
313 return load_aux(L, status, env);
314 }
315 #endif
316
317
318 /*
319 ** {======================================================
320 ** Generic Read function
321 ** =======================================================
322 */
323
324
325 /*
326 ** reserved slot, above all arguments, to hold a copy of the returned
327 ** string to avoid it being collected while parsed. 'load' has four
328 ** optional arguments (chunk, source name, mode, and environment).
329 */
330 #define RESERVEDSLOT 5
331
332
333 /*
334 ** Reader for generic 'load' function: 'lua_load' uses the
335 ** stack for internal stuff, so the reader cannot change the
336 ** stack top. Instead, it keeps its resulting string in a
337 ** reserved slot inside the stack.
338 */
generic_reader(lua_State * L,void * ud,size_t * size)339 static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
340 (void)(ud); /* not used */
341 luaL_checkstack(L, 2, "too many nested functions");
342 lua_pushvalue(L, 1); /* get function */
343 lua_call(L, 0, 1); /* call it */
344 if (lua_isnil(L, -1)) {
345 lua_pop(L, 1); /* pop result */
346 *size = 0;
347 return NULL;
348 }
349 else if (!lua_isstring(L, -1))
350 luaL_error(L, "reader function must return a string");
351 lua_replace(L, RESERVEDSLOT); /* save string in reserved slot */
352 return lua_tolstring(L, RESERVEDSLOT, size);
353 }
354
355
luaB_load(lua_State * L)356 static int luaB_load (lua_State *L) {
357 int status;
358 size_t l;
359 const char *s = lua_tolstring(L, 1, &l);
360 const char *mode = luaL_optstring(L, 3, "bt");
361 int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */
362 if (s != NULL) { /* loading a string? */
363 const char *chunkname = luaL_optstring(L, 2, s);
364 status = luaL_loadbufferx(L, s, l, chunkname, mode);
365 }
366 else { /* loading from a reader function */
367 const char *chunkname = luaL_optstring(L, 2, "=(load)");
368 luaL_checktype(L, 1, LUA_TFUNCTION);
369 lua_settop(L, RESERVEDSLOT); /* create reserved slot */
370 status = lua_load(L, generic_reader, NULL, chunkname, mode);
371 }
372 return load_aux(L, status, env);
373 }
374
375 /* }====================================================== */
376
377
378 #ifndef _KERNEL
dofilecont(lua_State * L,int d1,lua_KContext d2)379 static int dofilecont (lua_State *L, int d1, lua_KContext d2) {
380 (void)d1; (void)d2; /* only to match 'lua_Kfunction' prototype */
381 return lua_gettop(L) - 1;
382 }
383
384
luaB_dofile(lua_State * L)385 static int luaB_dofile (lua_State *L) {
386 const char *fname = luaL_optstring(L, 1, NULL);
387 lua_settop(L, 1);
388 if (luaL_loadfile(L, fname) != LUA_OK)
389 return lua_error(L);
390 lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
391 return dofilecont(L, 0, 0);
392 }
393 #endif
394
395
luaB_assert(lua_State * L)396 static int luaB_assert (lua_State *L) {
397 if (lua_toboolean(L, 1)) /* condition is true? */
398 return lua_gettop(L); /* return all arguments */
399 else { /* error */
400 luaL_checkany(L, 1); /* there must be a condition */
401 lua_remove(L, 1); /* remove it */
402 lua_pushliteral(L, "assertion failed!"); /* default message */
403 lua_settop(L, 1); /* leave only message (default if no other one) */
404 return luaB_error(L); /* call 'error' */
405 }
406 }
407
408
luaB_select(lua_State * L)409 static int luaB_select (lua_State *L) {
410 int n = lua_gettop(L);
411 if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
412 lua_pushinteger(L, n-1);
413 return 1;
414 }
415 else {
416 lua_Integer i = luaL_checkinteger(L, 1);
417 if (i < 0) i = n + i;
418 else if (i > n) i = n;
419 luaL_argcheck(L, 1 <= i, 1, "index out of range");
420 return n - (int)i;
421 }
422 }
423
424
425 /*
426 ** Continuation function for 'pcall' and 'xpcall'. Both functions
427 ** already pushed a 'true' before doing the call, so in case of success
428 ** 'finishpcall' only has to return everything in the stack minus
429 ** 'extra' values (where 'extra' is exactly the number of items to be
430 ** ignored).
431 */
finishpcall(lua_State * L,int status,lua_KContext extra)432 static int finishpcall (lua_State *L, int status, lua_KContext extra) {
433 if (status != LUA_OK && status != LUA_YIELD) { /* error? */
434 lua_pushboolean(L, 0); /* first result (false) */
435 lua_pushvalue(L, -2); /* error message */
436 return 2; /* return false, msg */
437 }
438 else
439 return lua_gettop(L) - (int)extra; /* return all results */
440 }
441
442
luaB_pcall(lua_State * L)443 static int luaB_pcall (lua_State *L) {
444 int status;
445 luaL_checkany(L, 1);
446 lua_pushboolean(L, 1); /* first result if no errors */
447 lua_insert(L, 1); /* put it in place */
448 status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
449 return finishpcall(L, status, 0);
450 }
451
452
453 /*
454 ** Do a protected call with error handling. After 'lua_rotate', the
455 ** stack will have <f, err, true, f, [args...]>; so, the function passes
456 ** 2 to 'finishpcall' to skip the 2 first values when returning results.
457 */
luaB_xpcall(lua_State * L)458 static int luaB_xpcall (lua_State *L) {
459 int status;
460 int n = lua_gettop(L);
461 luaL_checktype(L, 2, LUA_TFUNCTION); /* check error function */
462 lua_pushboolean(L, 1); /* first result */
463 lua_pushvalue(L, 1); /* function */
464 lua_rotate(L, 3, 2); /* move them below function's arguments */
465 status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
466 return finishpcall(L, status, 2);
467 }
468
469
luaB_tostring(lua_State * L)470 static int luaB_tostring (lua_State *L) {
471 luaL_checkany(L, 1);
472 luaL_tolstring(L, 1, NULL);
473 return 1;
474 }
475
476
477 static const luaL_Reg base_funcs[] = {
478 {"assert", luaB_assert},
479 {"collectgarbage", luaB_collectgarbage},
480 #ifndef _KERNEL
481 {"dofile", luaB_dofile},
482 #endif
483 {"error", luaB_error},
484 {"getmetatable", luaB_getmetatable},
485 {"ipairs", luaB_ipairs},
486 #ifndef _KERNEL
487 {"loadfile", luaB_loadfile},
488 #endif
489 {"load", luaB_load},
490 #if defined(LUA_COMPAT_LOADSTRING)
491 {"loadstring", luaB_load},
492 #endif
493 {"next", luaB_next},
494 {"pairs", luaB_pairs},
495 {"pcall", luaB_pcall},
496 {"print", luaB_print},
497 {"rawequal", luaB_rawequal},
498 {"rawlen", luaB_rawlen},
499 {"rawget", luaB_rawget},
500 {"rawset", luaB_rawset},
501 {"select", luaB_select},
502 {"setmetatable", luaB_setmetatable},
503 {"tonumber", luaB_tonumber},
504 {"tostring", luaB_tostring},
505 {"xpcall", luaB_xpcall},
506 /* placeholders */
507 {"type", NULL},
508 {"_G", NULL},
509 {"_VERSION", NULL},
510 {NULL, NULL}
511 };
512
513
luaopen_base(lua_State * L)514 LUAMOD_API int luaopen_base (lua_State *L) {
515 int i;
516 /* open lib into global table */
517 lua_pushglobaltable(L);
518 luaL_setfuncs(L, base_funcs, 0);
519 /* set global _G */
520 lua_pushvalue(L, -1);
521 lua_setfield(L, -2, "_G");
522 /* set global _VERSION */
523 lua_pushliteral(L, LUA_VERSION);
524 lua_setfield(L, -2, "_VERSION");
525 /* set function 'type' with proper upvalues */
526 for (i = 0; i < LUA_NUMTAGS; i++) /* push all type names as upvalues */
527 lua_pushstring(L, lua_typename(L, i));
528 lua_pushcclosure(L, luaB_type, LUA_NUMTAGS);
529 lua_setfield(L, -2, "type");
530 return 1;
531 }
532
533