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-rw-r--r--src/lua/lobject.c583
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diff --git a/src/lua/lobject.c b/src/lua/lobject.c
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1/*
2** $Id: lobject.c $
3** Some generic functions over Lua objects
4** See Copyright Notice in lua.h
5*/
6
7#define lobject_c
8#define LUA_CORE
9
10#include "lprefix.h"
11
12
13#include <locale.h>
14#include <math.h>
15#include <stdarg.h>
16#include <stdio.h>
17#include <stdlib.h>
18#include <string.h>
19
20#include "lua.h"
21
22#include "lctype.h"
23#include "ldebug.h"
24#include "ldo.h"
25#include "lmem.h"
26#include "lobject.h"
27#include "lstate.h"
28#include "lstring.h"
29#include "lvm.h"
30
31
32/*
33** Computes ceil(log2(x))
34*/
35int luaO_ceillog2 (unsigned int x) {
36 static const lu_byte log_2[256] = { /* log_2[i] = ceil(log2(i - 1)) */
37 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
38 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
39 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
40 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
41 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
42 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
43 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
44 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
45 };
46 int l = 0;
47 x--;
48 while (x >= 256) { l += 8; x >>= 8; }
49 return l + log_2[x];
50}
51
52
53static lua_Integer intarith (lua_State *L, int op, lua_Integer v1,
54 lua_Integer v2) {
55 switch (op) {
56 case LUA_OPADD: return intop(+, v1, v2);
57 case LUA_OPSUB:return intop(-, v1, v2);
58 case LUA_OPMUL:return intop(*, v1, v2);
59 case LUA_OPMOD: return luaV_mod(L, v1, v2);
60 case LUA_OPIDIV: return luaV_idiv(L, v1, v2);
61 case LUA_OPBAND: return intop(&, v1, v2);
62 case LUA_OPBOR: return intop(|, v1, v2);
63 case LUA_OPBXOR: return intop(^, v1, v2);
64 case LUA_OPSHL: return luaV_shiftl(v1, v2);
65 case LUA_OPSHR: return luaV_shiftl(v1, -v2);
66 case LUA_OPUNM: return intop(-, 0, v1);
67 case LUA_OPBNOT: return intop(^, ~l_castS2U(0), v1);
68 default: lua_assert(0); return 0;
69 }
70}
71
72
73static lua_Number numarith (lua_State *L, int op, lua_Number v1,
74 lua_Number v2) {
75 switch (op) {
76 case LUA_OPADD: return luai_numadd(L, v1, v2);
77 case LUA_OPSUB: return luai_numsub(L, v1, v2);
78 case LUA_OPMUL: return luai_nummul(L, v1, v2);
79 case LUA_OPDIV: return luai_numdiv(L, v1, v2);
80 case LUA_OPPOW: return luai_numpow(L, v1, v2);
81 case LUA_OPIDIV: return luai_numidiv(L, v1, v2);
82 case LUA_OPUNM: return luai_numunm(L, v1);
83 case LUA_OPMOD: return luaV_modf(L, v1, v2);
84 default: lua_assert(0); return 0;
85 }
86}
87
88
89int luaO_rawarith (lua_State *L, int op, const TValue *p1, const TValue *p2,
90 TValue *res) {
91 switch (op) {
92 case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR:
93 case LUA_OPSHL: case LUA_OPSHR:
94 case LUA_OPBNOT: { /* operate only on integers */
95 lua_Integer i1; lua_Integer i2;
96 if (tointegerns(p1, &i1) && tointegerns(p2, &i2)) {
97 setivalue(res, intarith(L, op, i1, i2));
98 return 1;
99 }
100 else return 0; /* fail */
101 }
102 case LUA_OPDIV: case LUA_OPPOW: { /* operate only on floats */
103 lua_Number n1; lua_Number n2;
104 if (tonumberns(p1, n1) && tonumberns(p2, n2)) {
105 setfltvalue(res, numarith(L, op, n1, n2));
106 return 1;
107 }
108 else return 0; /* fail */
109 }
110 default: { /* other operations */
111 lua_Number n1; lua_Number n2;
112 if (ttisinteger(p1) && ttisinteger(p2)) {
113 setivalue(res, intarith(L, op, ivalue(p1), ivalue(p2)));
114 return 1;
115 }
116 else if (tonumberns(p1, n1) && tonumberns(p2, n2)) {
117 setfltvalue(res, numarith(L, op, n1, n2));
118 return 1;
119 }
120 else return 0; /* fail */
121 }
122 }
123}
124
125
126void luaO_arith (lua_State *L, int op, const TValue *p1, const TValue *p2,
127 StkId res) {
128 if (!luaO_rawarith(L, op, p1, p2, s2v(res))) {
129 /* could not perform raw operation; try metamethod */
130 luaT_trybinTM(L, p1, p2, res, cast(TMS, (op - LUA_OPADD) + TM_ADD));
131 }
132}
133
134
135int luaO_hexavalue (int c) {
136 if (lisdigit(c)) return c - '0';
137 else return (ltolower(c) - 'a') + 10;
138}
139
140
141static int isneg (const char **s) {
142 if (**s == '-') { (*s)++; return 1; }
143 else if (**s == '+') (*s)++;
144 return 0;
145}
146
147
148
149/*
150** {==================================================================
151** Lua's implementation for 'lua_strx2number'
152** ===================================================================
153*/
154
155#if !defined(lua_strx2number)
156
157/* maximum number of significant digits to read (to avoid overflows
158 even with single floats) */
159#define MAXSIGDIG 30
160
161/*
162** convert a hexadecimal numeric string to a number, following
163** C99 specification for 'strtod'
164*/
165static lua_Number lua_strx2number (const char *s, char **endptr) {
166 int dot = lua_getlocaledecpoint();
167 lua_Number r = 0.0; /* result (accumulator) */
168 int sigdig = 0; /* number of significant digits */
169 int nosigdig = 0; /* number of non-significant digits */
170 int e = 0; /* exponent correction */
171 int neg; /* 1 if number is negative */
172 int hasdot = 0; /* true after seen a dot */
173 *endptr = cast_charp(s); /* nothing is valid yet */
174 while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */
175 neg = isneg(&s); /* check sign */
176 if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X'))) /* check '0x' */
177 return 0.0; /* invalid format (no '0x') */
178 for (s += 2; ; s++) { /* skip '0x' and read numeral */
179 if (*s == dot) {
180 if (hasdot) break; /* second dot? stop loop */
181 else hasdot = 1;
182 }
183 else if (lisxdigit(cast_uchar(*s))) {
184 if (sigdig == 0 && *s == '0') /* non-significant digit (zero)? */
185 nosigdig++;
186 else if (++sigdig <= MAXSIGDIG) /* can read it without overflow? */
187 r = (r * cast_num(16.0)) + luaO_hexavalue(*s);
188 else e++; /* too many digits; ignore, but still count for exponent */
189 if (hasdot) e--; /* decimal digit? correct exponent */
190 }
191 else break; /* neither a dot nor a digit */
192 }
193 if (nosigdig + sigdig == 0) /* no digits? */
194 return 0.0; /* invalid format */
195 *endptr = cast_charp(s); /* valid up to here */
196 e *= 4; /* each digit multiplies/divides value by 2^4 */
197 if (*s == 'p' || *s == 'P') { /* exponent part? */
198 int exp1 = 0; /* exponent value */
199 int neg1; /* exponent sign */
200 s++; /* skip 'p' */
201 neg1 = isneg(&s); /* sign */
202 if (!lisdigit(cast_uchar(*s)))
203 return 0.0; /* invalid; must have at least one digit */
204 while (lisdigit(cast_uchar(*s))) /* read exponent */
205 exp1 = exp1 * 10 + *(s++) - '0';
206 if (neg1) exp1 = -exp1;
207 e += exp1;
208 *endptr = cast_charp(s); /* valid up to here */
209 }
210 if (neg) r = -r;
211 return l_mathop(ldexp)(r, e);
212}
213
214#endif
215/* }====================================================== */
216
217
218/* maximum length of a numeral */
219#if !defined (L_MAXLENNUM)
220#define L_MAXLENNUM 200
221#endif
222
223static const char *l_str2dloc (const char *s, lua_Number *result, int mode) {
224 char *endptr;
225 *result = (mode == 'x') ? lua_strx2number(s, &endptr) /* try to convert */
226 : lua_str2number(s, &endptr);
227 if (endptr == s) return NULL; /* nothing recognized? */
228 while (lisspace(cast_uchar(*endptr))) endptr++; /* skip trailing spaces */
229 return (*endptr == '\0') ? endptr : NULL; /* OK if no trailing characters */
230}
231
232
233/*
234** Convert string 's' to a Lua number (put in 'result'). Return NULL
235** on fail or the address of the ending '\0' on success.
236** 'pmode' points to (and 'mode' contains) special things in the string:
237** - 'x'/'X' means a hexadecimal numeral
238** - 'n'/'N' means 'inf' or 'nan' (which should be rejected)
239** - '.' just optimizes the search for the common case (nothing special)
240** This function accepts both the current locale or a dot as the radix
241** mark. If the conversion fails, it may mean number has a dot but
242** locale accepts something else. In that case, the code copies 's'
243** to a buffer (because 's' is read-only), changes the dot to the
244** current locale radix mark, and tries to convert again.
245*/
246static const char *l_str2d (const char *s, lua_Number *result) {
247 const char *endptr;
248 const char *pmode = strpbrk(s, ".xXnN");
249 int mode = pmode ? ltolower(cast_uchar(*pmode)) : 0;
250 if (mode == 'n') /* reject 'inf' and 'nan' */
251 return NULL;
252 endptr = l_str2dloc(s, result, mode); /* try to convert */
253 if (endptr == NULL) { /* failed? may be a different locale */
254 char buff[L_MAXLENNUM + 1];
255 const char *pdot = strchr(s, '.');
256 if (strlen(s) > L_MAXLENNUM || pdot == NULL)
257 return NULL; /* string too long or no dot; fail */
258 strcpy(buff, s); /* copy string to buffer */
259 buff[pdot - s] = lua_getlocaledecpoint(); /* correct decimal point */
260 endptr = l_str2dloc(buff, result, mode); /* try again */
261 if (endptr != NULL)
262 endptr = s + (endptr - buff); /* make relative to 's' */
263 }
264 return endptr;
265}
266
267
268#define MAXBY10 cast(lua_Unsigned, LUA_MAXINTEGER / 10)
269#define MAXLASTD cast_int(LUA_MAXINTEGER % 10)
270
271static const char *l_str2int (const char *s, lua_Integer *result) {
272 lua_Unsigned a = 0;
273 int empty = 1;
274 int neg;
275 while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */
276 neg = isneg(&s);
277 if (s[0] == '0' &&
278 (s[1] == 'x' || s[1] == 'X')) { /* hex? */
279 s += 2; /* skip '0x' */
280 for (; lisxdigit(cast_uchar(*s)); s++) {
281 a = a * 16 + luaO_hexavalue(*s);
282 empty = 0;
283 }
284 }
285 else { /* decimal */
286 for (; lisdigit(cast_uchar(*s)); s++) {
287 int d = *s - '0';
288 if (a >= MAXBY10 && (a > MAXBY10 || d > MAXLASTD + neg)) /* overflow? */
289 return NULL; /* do not accept it (as integer) */
290 a = a * 10 + d;
291 empty = 0;
292 }
293 }
294 while (lisspace(cast_uchar(*s))) s++; /* skip trailing spaces */
295 if (empty || *s != '\0') return NULL; /* something wrong in the numeral */
296 else {
297 *result = l_castU2S((neg) ? 0u - a : a);
298 return s;
299 }
300}
301
302
303size_t luaO_str2num (const char *s, TValue *o) {
304 lua_Integer i; lua_Number n;
305 const char *e;
306 if ((e = l_str2int(s, &i)) != NULL) { /* try as an integer */
307 setivalue(o, i);
308 }
309 else if ((e = l_str2d(s, &n)) != NULL) { /* else try as a float */
310 setfltvalue(o, n);
311 }
312 else
313 return 0; /* conversion failed */
314 return (e - s) + 1; /* success; return string size */
315}
316
317
318int luaO_utf8esc (char *buff, unsigned long x) {
319 int n = 1; /* number of bytes put in buffer (backwards) */
320 lua_assert(x <= 0x7FFFFFFFu);
321 if (x < 0x80) /* ascii? */
322 buff[UTF8BUFFSZ - 1] = cast_char(x);
323 else { /* need continuation bytes */
324 unsigned int mfb = 0x3f; /* maximum that fits in first byte */
325 do { /* add continuation bytes */
326 buff[UTF8BUFFSZ - (n++)] = cast_char(0x80 | (x & 0x3f));
327 x >>= 6; /* remove added bits */
328 mfb >>= 1; /* now there is one less bit available in first byte */
329 } while (x > mfb); /* still needs continuation byte? */
330 buff[UTF8BUFFSZ - n] = cast_char((~mfb << 1) | x); /* add first byte */
331 }
332 return n;
333}
334
335
336/* maximum length of the conversion of a number to a string */
337#define MAXNUMBER2STR 50
338
339
340/*
341** Convert a number object to a string, adding it to a buffer
342*/
343static int tostringbuff (TValue *obj, char *buff) {
344 int len;
345 lua_assert(ttisnumber(obj));
346 if (ttisinteger(obj))
347 len = lua_integer2str(buff, MAXNUMBER2STR, ivalue(obj));
348 else {
349 len = lua_number2str(buff, MAXNUMBER2STR, fltvalue(obj));
350 if (buff[strspn(buff, "-0123456789")] == '\0') { /* looks like an int? */
351 buff[len++] = lua_getlocaledecpoint();
352 buff[len++] = '0'; /* adds '.0' to result */
353 }
354 }
355 return len;
356}
357
358
359/*
360** Convert a number object to a Lua string, replacing the value at 'obj'
361*/
362void luaO_tostring (lua_State *L, TValue *obj) {
363 char buff[MAXNUMBER2STR];
364 int len = tostringbuff(obj, buff);
365 setsvalue(L, obj, luaS_newlstr(L, buff, len));
366}
367
368
369
370
371/*
372** {==================================================================
373** 'luaO_pushvfstring'
374** ===================================================================
375*/
376
377/* size for buffer space used by 'luaO_pushvfstring' */
378#define BUFVFS 400
379
380/* buffer used by 'luaO_pushvfstring' */
381typedef struct BuffFS {
382 lua_State *L;
383 int pushed; /* number of string pieces already on the stack */
384 int blen; /* length of partial string in 'space' */
385 char space[BUFVFS]; /* holds last part of the result */
386} BuffFS;
387
388
389/*
390** Push given string to the stack, as part of the buffer. If the stack
391** is almost full, join all partial strings in the stack into one.
392*/
393static void pushstr (BuffFS *buff, const char *str, size_t l) {
394 lua_State *L = buff->L;
395 setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
396 L->top++; /* may use one extra slot */
397 buff->pushed++;
398 if (buff->pushed > 1 && L->top + 1 >= L->stack_last) {
399 luaV_concat(L, buff->pushed); /* join all partial results into one */
400 buff->pushed = 1;
401 }
402}
403
404
405/*
406** empty the buffer space into the stack
407*/
408static void clearbuff (BuffFS *buff) {
409 pushstr(buff, buff->space, buff->blen); /* push buffer contents */
410 buff->blen = 0; /* space now is empty */
411}
412
413
414/*
415** Get a space of size 'sz' in the buffer. If buffer has not enough
416** space, empty it. 'sz' must fit in an empty buffer.
417*/
418static char *getbuff (BuffFS *buff, int sz) {
419 lua_assert(buff->blen <= BUFVFS); lua_assert(sz <= BUFVFS);
420 if (sz > BUFVFS - buff->blen) /* not enough space? */
421 clearbuff(buff);
422 return buff->space + buff->blen;
423}
424
425
426#define addsize(b,sz) ((b)->blen += (sz))
427
428
429/*
430** Add 'str' to the buffer. If string is larger than the buffer space,
431** push the string directly to the stack.
432*/
433static void addstr2buff (BuffFS *buff, const char *str, size_t slen) {
434 if (slen <= BUFVFS) { /* does string fit into buffer? */
435 char *bf = getbuff(buff, cast_int(slen));
436 memcpy(bf, str, slen); /* add string to buffer */
437 addsize(buff, cast_int(slen));
438 }
439 else { /* string larger than buffer */
440 clearbuff(buff); /* string comes after buffer's content */
441 pushstr(buff, str, slen); /* push string */
442 }
443}
444
445
446/*
447** Add a number to the buffer.
448*/
449static void addnum2buff (BuffFS *buff, TValue *num) {
450 char *numbuff = getbuff(buff, MAXNUMBER2STR);
451 int len = tostringbuff(num, numbuff); /* format number into 'numbuff' */
452 addsize(buff, len);
453}
454
455
456/*
457** this function handles only '%d', '%c', '%f', '%p', '%s', and '%%'
458 conventional formats, plus Lua-specific '%I' and '%U'
459*/
460const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
461 BuffFS buff; /* holds last part of the result */
462 const char *e; /* points to next '%' */
463 buff.pushed = buff.blen = 0;
464 buff.L = L;
465 while ((e = strchr(fmt, '%')) != NULL) {
466 addstr2buff(&buff, fmt, e - fmt); /* add 'fmt' up to '%' */
467 switch (*(e + 1)) { /* conversion specifier */
468 case 's': { /* zero-terminated string */
469 const char *s = va_arg(argp, char *);
470 if (s == NULL) s = "(null)";
471 addstr2buff(&buff, s, strlen(s));
472 break;
473 }
474 case 'c': { /* an 'int' as a character */
475 char c = cast_uchar(va_arg(argp, int));
476 addstr2buff(&buff, &c, sizeof(char));
477 break;
478 }
479 case 'd': { /* an 'int' */
480 TValue num;
481 setivalue(&num, va_arg(argp, int));
482 addnum2buff(&buff, &num);
483 break;
484 }
485 case 'I': { /* a 'lua_Integer' */
486 TValue num;
487 setivalue(&num, cast(lua_Integer, va_arg(argp, l_uacInt)));
488 addnum2buff(&buff, &num);
489 break;
490 }
491 case 'f': { /* a 'lua_Number' */
492 TValue num;
493 setfltvalue(&num, cast_num(va_arg(argp, l_uacNumber)));
494 addnum2buff(&buff, &num);
495 break;
496 }
497 case 'p': { /* a pointer */
498 const int sz = 3 * sizeof(void*) + 8; /* enough space for '%p' */
499 char *bf = getbuff(&buff, sz);
500 void *p = va_arg(argp, void *);
501 int len = lua_pointer2str(bf, sz, p);
502 addsize(&buff, len);
503 break;
504 }
505 case 'U': { /* a 'long' as a UTF-8 sequence */
506 char bf[UTF8BUFFSZ];
507 int len = luaO_utf8esc(bf, va_arg(argp, long));
508 addstr2buff(&buff, bf + UTF8BUFFSZ - len, len);
509 break;
510 }
511 case '%': {
512 addstr2buff(&buff, "%", 1);
513 break;
514 }
515 default: {
516 luaG_runerror(L, "invalid option '%%%c' to 'lua_pushfstring'",
517 *(e + 1));
518 }
519 }
520 fmt = e + 2; /* skip '%' and the specifier */
521 }
522 addstr2buff(&buff, fmt, strlen(fmt)); /* rest of 'fmt' */
523 clearbuff(&buff); /* empty buffer into the stack */
524 if (buff.pushed > 1)
525 luaV_concat(L, buff.pushed); /* join all partial results */
526 return svalue(s2v(L->top - 1));
527}
528
529
530const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {
531 const char *msg;
532 va_list argp;
533 va_start(argp, fmt);
534 msg = luaO_pushvfstring(L, fmt, argp);
535 va_end(argp);
536 return msg;
537}
538
539/* }================================================================== */
540
541
542#define RETS "..."
543#define PRE "[string \""
544#define POS "\"]"
545
546#define addstr(a,b,l) ( memcpy(a,b,(l) * sizeof(char)), a += (l) )
547
548void luaO_chunkid (char *out, const char *source, size_t srclen) {
549 size_t bufflen = LUA_IDSIZE; /* free space in buffer */
550 if (*source == '=') { /* 'literal' source */
551 if (srclen <= bufflen) /* small enough? */
552 memcpy(out, source + 1, srclen * sizeof(char));
553 else { /* truncate it */
554 addstr(out, source + 1, bufflen - 1);
555 *out = '\0';
556 }
557 }
558 else if (*source == '@') { /* file name */
559 if (srclen <= bufflen) /* small enough? */
560 memcpy(out, source + 1, srclen * sizeof(char));
561 else { /* add '...' before rest of name */
562 addstr(out, RETS, LL(RETS));
563 bufflen -= LL(RETS);
564 memcpy(out, source + 1 + srclen - bufflen, bufflen * sizeof(char));
565 }
566 }
567 else { /* string; format as [string "source"] */
568 const char *nl = strchr(source, '\n'); /* find first new line (if any) */
569 addstr(out, PRE, LL(PRE)); /* add prefix */
570 bufflen -= LL(PRE RETS POS) + 1; /* save space for prefix+suffix+'\0' */
571 if (srclen < bufflen && nl == NULL) { /* small one-line source? */
572 addstr(out, source, srclen); /* keep it */
573 }
574 else {
575 if (nl != NULL) srclen = nl - source; /* stop at first newline */
576 if (srclen > bufflen) srclen = bufflen;
577 addstr(out, source, srclen);
578 addstr(out, RETS, LL(RETS));
579 }
580 memcpy(out, POS, (LL(POS) + 1) * sizeof(char));
581 }
582}
583