1/*
2** String library.
3** Copyright (C) 2005-2014 Mike Pall. See Copyright Notice in luajit.h
4**
5** Major portions taken verbatim or adapted from the Lua interpreter.
6** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
7*/
8
9#include <stdio.h>
10
11#define lib_string_c
12#define LUA_LIB
13
14#include "lua.h"
15#include "lauxlib.h"
16#include "lualib.h"
17
18#include "lj_obj.h"
19#include "lj_gc.h"
20#include "lj_err.h"
21#include "lj_str.h"
22#include "lj_tab.h"
23#include "lj_meta.h"
24#include "lj_state.h"
25#include "lj_ff.h"
26#include "lj_bcdump.h"
27#include "lj_char.h"
28#include "lj_lib.h"
29
30/* ------------------------------------------------------------------------ */
31
32#define LJLIB_MODULE_string
33
34LJLIB_ASM(string_len) LJLIB_REC(.)
35{
36 lj_lib_checkstr(L, 1);
37 return FFH_RETRY;
38}
39
40LJLIB_ASM(string_byte) LJLIB_REC(string_range 0)
41{
42 GCstr *s = lj_lib_checkstr(L, 1);
43 int32_t len = (int32_t)s->len;
44 int32_t start = lj_lib_optint(L, 2, 1);
45 int32_t stop = lj_lib_optint(L, 3, start);
46 int32_t n, i;
47 const unsigned char *p;
48 if (stop < 0) stop += len+1;
49 if (start < 0) start += len+1;
50 if (start <= 0) start = 1;
51 if (stop > len) stop = len;
52 if (start > stop) return FFH_RES(0); /* Empty interval: return no results. */
53 start--;
54 n = stop - start;
55 if ((uint32_t)n > LUAI_MAXCSTACK)
56 lj_err_caller(L, LJ_ERR_STRSLC);
57 lj_state_checkstack(L, (MSize)n);
58 p = (const unsigned char *)strdata(s) + start;
59 for (i = 0; i < n; i++)
60 setintV(L->base + i-1, p[i]);
61 return FFH_RES(n);
62}
63
64LJLIB_ASM(string_char)
65{
66 int i, nargs = (int)(L->top - L->base);
67 char *buf = lj_str_needbuf(L, &G(L)->tmpbuf, (MSize)nargs);
68 for (i = 1; i <= nargs; i++) {
69 int32_t k = lj_lib_checkint(L, i);
70 if (!checku8(k))
71 lj_err_arg(L, i, LJ_ERR_BADVAL);
72 buf[i-1] = (char)k;
73 }
74 setstrV(L, L->base-1, lj_str_new(L, buf, (size_t)nargs));
75 return FFH_RES(1);
76}
77
78LJLIB_ASM(string_sub) LJLIB_REC(string_range 1)
79{
80 lj_lib_checkstr(L, 1);
81 lj_lib_checkint(L, 2);
82 setintV(L->base+2, lj_lib_optint(L, 3, -1));
83 return FFH_RETRY;
84}
85
86LJLIB_ASM(string_rep)
87{
88 GCstr *s = lj_lib_checkstr(L, 1);
89 int32_t k = lj_lib_checkint(L, 2);
90 GCstr *sep = lj_lib_optstr(L, 3);
91 int32_t len = (int32_t)s->len;
92 global_State *g = G(L);
93 int64_t tlen;
94 const char *src;
95 char *buf;
96 if (k <= 0) {
97 empty:
98 setstrV(L, L->base-1, &g->strempty);
99 return FFH_RES(1);
100 }
101 if (sep) {
102 tlen = (int64_t)len + sep->len;
103 if (tlen > LJ_MAX_STR)
104 lj_err_caller(L, LJ_ERR_STROV);
105 tlen *= k;
106 if (tlen > LJ_MAX_STR)
107 lj_err_caller(L, LJ_ERR_STROV);
108 } else {
109 tlen = (int64_t)k * len;
110 if (tlen > LJ_MAX_STR)
111 lj_err_caller(L, LJ_ERR_STROV);
112 }
113 if (tlen == 0) goto empty;
114 buf = lj_str_needbuf(L, &g->tmpbuf, (MSize)tlen);
115 src = strdata(s);
116 if (sep) {
117 tlen -= sep->len; /* Ignore trailing separator. */
118 if (k > 1) { /* Paste one string and one separator. */
119 int32_t i;
120 i = 0; while (i < len) *buf++ = src[i++];
121 src = strdata(sep); len = sep->len;
122 i = 0; while (i < len) *buf++ = src[i++];
123 src = g->tmpbuf.buf; len += s->len; k--; /* Now copy that k-1 times. */
124 }
125 }
126 do {
127 int32_t i = 0;
128 do { *buf++ = src[i++]; } while (i < len);
129 } while (--k > 0);
130 setstrV(L, L->base-1, lj_str_new(L, g->tmpbuf.buf, (size_t)tlen));
131 return FFH_RES(1);
132}
133
134LJLIB_ASM(string_reverse)
135{
136 GCstr *s = lj_lib_checkstr(L, 1);
137 lj_str_needbuf(L, &G(L)->tmpbuf, s->len);
138 return FFH_RETRY;
139}
140LJLIB_ASM_(string_lower)
141LJLIB_ASM_(string_upper)
142
143/* ------------------------------------------------------------------------ */
144
145static int writer_buf(lua_State *L, const void *p, size_t size, void *b)
146{
147 luaL_addlstring((luaL_Buffer *)b, (const char *)p, size);
148 UNUSED(L);
149 return 0;
150}
151
152LJLIB_CF(string_dump)
153{
154 GCfunc *fn = lj_lib_checkfunc(L, 1);
155 int strip = L->base+1 < L->top && tvistruecond(L->base+1);
156 luaL_Buffer b;
157 L->top = L->base+1;
158 luaL_buffinit(L, &b);
159 if (!isluafunc(fn) || lj_bcwrite(L, funcproto(fn), writer_buf, &b, strip))
160 lj_err_caller(L, LJ_ERR_STRDUMP);
161 luaL_pushresult(&b);
162 return 1;
163}
164
165/* ------------------------------------------------------------------------ */
166
167/* macro to `unsign' a character */
168#define uchar(c) ((unsigned char)(c))
169
170#define CAP_UNFINISHED (-1)
171#define CAP_POSITION (-2)
172
173typedef struct MatchState {
174 const char *src_init; /* init of source string */
175 const char *src_end; /* end (`\0') of source string */
176 lua_State *L;
177 int level; /* total number of captures (finished or unfinished) */
178 int depth;
179 struct {
180 const char *init;
181 ptrdiff_t len;
182 } capture[LUA_MAXCAPTURES];
183} MatchState;
184
185#define L_ESC '%'
186#define SPECIALS "^$*+?.([%-"
187
188static int check_capture(MatchState *ms, int l)
189{
190 l -= '1';
191 if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
192 lj_err_caller(ms->L, LJ_ERR_STRCAPI);
193 return l;
194}
195
196static int capture_to_close(MatchState *ms)
197{
198 int level = ms->level;
199 for (level--; level>=0; level--)
200 if (ms->capture[level].len == CAP_UNFINISHED) return level;
201 lj_err_caller(ms->L, LJ_ERR_STRPATC);
202 return 0; /* unreachable */
203}
204
205static const char *classend(MatchState *ms, const char *p)
206{
207 switch (*p++) {
208 case L_ESC:
209 if (*p == '\0')
210 lj_err_caller(ms->L, LJ_ERR_STRPATE);
211 return p+1;
212 case '[':
213 if (*p == '^') p++;
214 do { /* look for a `]' */
215 if (*p == '\0')
216 lj_err_caller(ms->L, LJ_ERR_STRPATM);
217 if (*(p++) == L_ESC && *p != '\0')
218 p++; /* skip escapes (e.g. `%]') */
219 } while (*p != ']');
220 return p+1;
221 default:
222 return p;
223 }
224}
225
226static const unsigned char match_class_map[32] = {
227 0,LJ_CHAR_ALPHA,0,LJ_CHAR_CNTRL,LJ_CHAR_DIGIT,0,0,LJ_CHAR_GRAPH,0,0,0,0,
228 LJ_CHAR_LOWER,0,0,0,LJ_CHAR_PUNCT,0,0,LJ_CHAR_SPACE,0,
229 LJ_CHAR_UPPER,0,LJ_CHAR_ALNUM,LJ_CHAR_XDIGIT,0,0,0,0,0,0,0
230};
231
232static int match_class(int c, int cl)
233{
234 if ((cl & 0xc0) == 0x40) {
235 int t = match_class_map[(cl&0x1f)];
236 if (t) {
237 t = lj_char_isa(c, t);
238 return (cl & 0x20) ? t : !t;
239 }
240 if (cl == 'z') return c == 0;
241 if (cl == 'Z') return c != 0;
242 }
243 return (cl == c);
244}
245
246static int matchbracketclass(int c, const char *p, const char *ec)
247{
248 int sig = 1;
249 if (*(p+1) == '^') {
250 sig = 0;
251 p++; /* skip the `^' */
252 }
253 while (++p < ec) {
254 if (*p == L_ESC) {
255 p++;
256 if (match_class(c, uchar(*p)))
257 return sig;
258 }
259 else if ((*(p+1) == '-') && (p+2 < ec)) {
260 p+=2;
261 if (uchar(*(p-2)) <= c && c <= uchar(*p))
262 return sig;
263 }
264 else if (uchar(*p) == c) return sig;
265 }
266 return !sig;
267}
268
269static int singlematch(int c, const char *p, const char *ep)
270{
271 switch (*p) {
272 case '.': return 1; /* matches any char */
273 case L_ESC: return match_class(c, uchar(*(p+1)));
274 case '[': return matchbracketclass(c, p, ep-1);
275 default: return (uchar(*p) == c);
276 }
277}
278
279static const char *match(MatchState *ms, const char *s, const char *p);
280
281static const char *matchbalance(MatchState *ms, const char *s, const char *p)
282{
283 if (*p == 0 || *(p+1) == 0)
284 lj_err_caller(ms->L, LJ_ERR_STRPATU);
285 if (*s != *p) {
286 return NULL;
287 } else {
288 int b = *p;
289 int e = *(p+1);
290 int cont = 1;
291 while (++s < ms->src_end) {
292 if (*s == e) {
293 if (--cont == 0) return s+1;
294 } else if (*s == b) {
295 cont++;
296 }
297 }
298 }
299 return NULL; /* string ends out of balance */
300}
301
302static const char *max_expand(MatchState *ms, const char *s,
303 const char *p, const char *ep)
304{
305 ptrdiff_t i = 0; /* counts maximum expand for item */
306 while ((s+i)<ms->src_end && singlematch(uchar(*(s+i)), p, ep))
307 i++;
308 /* keeps trying to match with the maximum repetitions */
309 while (i>=0) {
310 const char *res = match(ms, (s+i), ep+1);
311 if (res) return res;
312 i--; /* else didn't match; reduce 1 repetition to try again */
313 }
314 return NULL;
315}
316
317static const char *min_expand(MatchState *ms, const char *s,
318 const char *p, const char *ep)
319{
320 for (;;) {
321 const char *res = match(ms, s, ep+1);
322 if (res != NULL)
323 return res;
324 else if (s<ms->src_end && singlematch(uchar(*s), p, ep))
325 s++; /* try with one more repetition */
326 else
327 return NULL;
328 }
329}
330
331static const char *start_capture(MatchState *ms, const char *s,
332 const char *p, int what)
333{
334 const char *res;
335 int level = ms->level;
336 if (level >= LUA_MAXCAPTURES) lj_err_caller(ms->L, LJ_ERR_STRCAPN);
337 ms->capture[level].init = s;
338 ms->capture[level].len = what;
339 ms->level = level+1;
340 if ((res=match(ms, s, p)) == NULL) /* match failed? */
341 ms->level--; /* undo capture */
342 return res;
343}
344
345static const char *end_capture(MatchState *ms, const char *s,
346 const char *p)
347{
348 int l = capture_to_close(ms);
349 const char *res;
350 ms->capture[l].len = s - ms->capture[l].init; /* close capture */
351 if ((res = match(ms, s, p)) == NULL) /* match failed? */
352 ms->capture[l].len = CAP_UNFINISHED; /* undo capture */
353 return res;
354}
355
356static const char *match_capture(MatchState *ms, const char *s, int l)
357{
358 size_t len;
359 l = check_capture(ms, l);
360 len = (size_t)ms->capture[l].len;
361 if ((size_t)(ms->src_end-s) >= len &&
362 memcmp(ms->capture[l].init, s, len) == 0)
363 return s+len;
364 else
365 return NULL;
366}
367
368static const char *match(MatchState *ms, const char *s, const char *p)
369{
370 if (++ms->depth > LJ_MAX_XLEVEL)
371 lj_err_caller(ms->L, LJ_ERR_STRPATX);
372 init: /* using goto's to optimize tail recursion */
373 switch (*p) {
374 case '(': /* start capture */
375 if (*(p+1) == ')') /* position capture? */
376 s = start_capture(ms, s, p+2, CAP_POSITION);
377 else
378 s = start_capture(ms, s, p+1, CAP_UNFINISHED);
379 break;
380 case ')': /* end capture */
381 s = end_capture(ms, s, p+1);
382 break;
383 case L_ESC:
384 switch (*(p+1)) {
385 case 'b': /* balanced string? */
386 s = matchbalance(ms, s, p+2);
387 if (s == NULL) break;
388 p+=4;
389 goto init; /* else s = match(ms, s, p+4); */
390 case 'f': { /* frontier? */
391 const char *ep; char previous;
392 p += 2;
393 if (*p != '[')
394 lj_err_caller(ms->L, LJ_ERR_STRPATB);
395 ep = classend(ms, p); /* points to what is next */
396 previous = (s == ms->src_init) ? '\0' : *(s-1);
397 if (matchbracketclass(uchar(previous), p, ep-1) ||
398 !matchbracketclass(uchar(*s), p, ep-1)) { s = NULL; break; }
399 p=ep;
400 goto init; /* else s = match(ms, s, ep); */
401 }
402 default:
403 if (lj_char_isdigit(uchar(*(p+1)))) { /* capture results (%0-%9)? */
404 s = match_capture(ms, s, uchar(*(p+1)));
405 if (s == NULL) break;
406 p+=2;
407 goto init; /* else s = match(ms, s, p+2) */
408 }
409 goto dflt; /* case default */
410 }
411 break;
412 case '\0': /* end of pattern */
413 break; /* match succeeded */
414 case '$':
415 /* is the `$' the last char in pattern? */
416 if (*(p+1) != '\0') goto dflt;
417 if (s != ms->src_end) s = NULL; /* check end of string */
418 break;
419 default: dflt: { /* it is a pattern item */
420 const char *ep = classend(ms, p); /* points to what is next */
421 int m = s<ms->src_end && singlematch(uchar(*s), p, ep);
422 switch (*ep) {
423 case '?': { /* optional */
424 const char *res;
425 if (m && ((res=match(ms, s+1, ep+1)) != NULL)) {
426 s = res;
427 break;
428 }
429 p=ep+1;
430 goto init; /* else s = match(ms, s, ep+1); */
431 }
432 case '*': /* 0 or more repetitions */
433 s = max_expand(ms, s, p, ep);
434 break;
435 case '+': /* 1 or more repetitions */
436 s = (m ? max_expand(ms, s+1, p, ep) : NULL);
437 break;
438 case '-': /* 0 or more repetitions (minimum) */
439 s = min_expand(ms, s, p, ep);
440 break;
441 default:
442 if (m) { s++; p=ep; goto init; } /* else s = match(ms, s+1, ep); */
443 s = NULL;
444 break;
445 }
446 break;
447 }
448 }
449 ms->depth--;
450 return s;
451}
452
453static const char *lmemfind(const char *s1, size_t l1,
454 const char *s2, size_t l2)
455{
456 if (l2 == 0) {
457 return s1; /* empty strings are everywhere */
458 } else if (l2 > l1) {
459 return NULL; /* avoids a negative `l1' */
460 } else {
461 const char *init; /* to search for a `*s2' inside `s1' */
462 l2--; /* 1st char will be checked by `memchr' */
463 l1 = l1-l2; /* `s2' cannot be found after that */
464 while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
465 init++; /* 1st char is already checked */
466 if (memcmp(init, s2+1, l2) == 0) {
467 return init-1;
468 } else { /* correct `l1' and `s1' to try again */
469 l1 -= (size_t)(init-s1);
470 s1 = init;
471 }
472 }
473 return NULL; /* not found */
474 }
475}
476
477static void push_onecapture(MatchState *ms, int i, const char *s, const char *e)
478{
479 if (i >= ms->level) {
480 if (i == 0) /* ms->level == 0, too */
481 lua_pushlstring(ms->L, s, (size_t)(e - s)); /* add whole match */
482 else
483 lj_err_caller(ms->L, LJ_ERR_STRCAPI);
484 } else {
485 ptrdiff_t l = ms->capture[i].len;
486 if (l == CAP_UNFINISHED) lj_err_caller(ms->L, LJ_ERR_STRCAPU);
487 if (l == CAP_POSITION)
488 lua_pushinteger(ms->L, ms->capture[i].init - ms->src_init + 1);
489 else
490 lua_pushlstring(ms->L, ms->capture[i].init, (size_t)l);
491 }
492}
493
494static int push_captures(MatchState *ms, const char *s, const char *e)
495{
496 int i;
497 int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
498 luaL_checkstack(ms->L, nlevels, "too many captures");
499 for (i = 0; i < nlevels; i++)
500 push_onecapture(ms, i, s, e);
501 return nlevels; /* number of strings pushed */
502}
503
504static ptrdiff_t posrelat(ptrdiff_t pos, size_t len)
505{
506 /* relative string position: negative means back from end */
507 if (pos < 0) pos += (ptrdiff_t)len + 1;
508 return (pos >= 0) ? pos : 0;
509}
510
511static int str_find_aux(lua_State *L, int find)
512{
513 size_t l1, l2;
514 const char *s = luaL_checklstring(L, 1, &l1);
515 const char *p = luaL_checklstring(L, 2, &l2);
516 ptrdiff_t init = posrelat(luaL_optinteger(L, 3, 1), l1) - 1;
517 if (init < 0) {
518 init = 0;
519 } else if ((size_t)(init) > l1) {
520#if LJ_52
521 setnilV(L->top-1);
522 return 1;
523#else
524 init = (ptrdiff_t)l1;
525#endif
526 }
527 if (find && (lua_toboolean(L, 4) || /* explicit request? */
528 strpbrk(p, SPECIALS) == NULL)) { /* or no special characters? */
529 /* do a plain search */
530 const char *s2 = lmemfind(s+init, l1-(size_t)init, p, l2);
531 if (s2) {
532 lua_pushinteger(L, s2-s+1);
533 lua_pushinteger(L, s2-s+(ptrdiff_t)l2);
534 return 2;
535 }
536 } else {
537 MatchState ms;
538 int anchor = (*p == '^') ? (p++, 1) : 0;
539 const char *s1=s+init;
540 ms.L = L;
541 ms.src_init = s;
542 ms.src_end = s+l1;
543 do {
544 const char *res;
545 ms.level = ms.depth = 0;
546 if ((res=match(&ms, s1, p)) != NULL) {
547 if (find) {
548 lua_pushinteger(L, s1-s+1); /* start */
549 lua_pushinteger(L, res-s); /* end */
550 return push_captures(&ms, NULL, 0) + 2;
551 } else {
552 return push_captures(&ms, s1, res);
553 }
554 }
555 } while (s1++ < ms.src_end && !anchor);
556 }
557 lua_pushnil(L); /* not found */
558 return 1;
559}
560
561LJLIB_CF(string_find)
562{
563 return str_find_aux(L, 1);
564}
565
566LJLIB_CF(string_match)
567{
568 return str_find_aux(L, 0);
569}
570
571LJLIB_NOREG LJLIB_CF(string_gmatch_aux)
572{
573 const char *p = strVdata(lj_lib_upvalue(L, 2));
574 GCstr *str = strV(lj_lib_upvalue(L, 1));
575 const char *s = strdata(str);
576 TValue *tvpos = lj_lib_upvalue(L, 3);
577 const char *src = s + tvpos->u32.lo;
578 MatchState ms;
579 ms.L = L;
580 ms.src_init = s;
581 ms.src_end = s + str->len;
582 for (; src <= ms.src_end; src++) {
583 const char *e;
584 ms.level = ms.depth = 0;
585 if ((e = match(&ms, src, p)) != NULL) {
586 int32_t pos = (int32_t)(e - s);
587 if (e == src) pos++; /* Ensure progress for empty match. */
588 tvpos->u32.lo = (uint32_t)pos;
589 return push_captures(&ms, src, e);
590 }
591 }
592 return 0; /* not found */
593}
594
595LJLIB_CF(string_gmatch)
596{
597 lj_lib_checkstr(L, 1);
598 lj_lib_checkstr(L, 2);
599 L->top = L->base+3;
600 (L->top-1)->u64 = 0;
601 lj_lib_pushcc(L, lj_cf_string_gmatch_aux, FF_string_gmatch_aux, 3);
602 return 1;
603}
604
605static void add_s(MatchState *ms, luaL_Buffer *b, const char *s, const char *e)
606{
607 size_t l, i;
608 const char *news = lua_tolstring(ms->L, 3, &l);
609 for (i = 0; i < l; i++) {
610 if (news[i] != L_ESC) {
611 luaL_addchar(b, news[i]);
612 } else {
613 i++; /* skip ESC */
614 if (!lj_char_isdigit(uchar(news[i]))) {
615 luaL_addchar(b, news[i]);
616 } else if (news[i] == '0') {
617 luaL_addlstring(b, s, (size_t)(e - s));
618 } else {
619 push_onecapture(ms, news[i] - '1', s, e);
620 luaL_addvalue(b); /* add capture to accumulated result */
621 }
622 }
623 }
624}
625
626static void add_value(MatchState *ms, luaL_Buffer *b,
627 const char *s, const char *e)
628{
629 lua_State *L = ms->L;
630 switch (lua_type(L, 3)) {
631 case LUA_TNUMBER:
632 case LUA_TSTRING: {
633 add_s(ms, b, s, e);
634 return;
635 }
636 case LUA_TFUNCTION: {
637 int n;
638 lua_pushvalue(L, 3);
639 n = push_captures(ms, s, e);
640 lua_call(L, n, 1);
641 break;
642 }
643 case LUA_TTABLE: {
644 push_onecapture(ms, 0, s, e);
645 lua_gettable(L, 3);
646 break;
647 }
648 }
649 if (!lua_toboolean(L, -1)) { /* nil or false? */
650 lua_pop(L, 1);
651 lua_pushlstring(L, s, (size_t)(e - s)); /* keep original text */
652 } else if (!lua_isstring(L, -1)) {
653 lj_err_callerv(L, LJ_ERR_STRGSRV, luaL_typename(L, -1));
654 }
655 luaL_addvalue(b); /* add result to accumulator */
656}
657
658LJLIB_CF(string_gsub)
659{
660 size_t srcl;
661 const char *src = luaL_checklstring(L, 1, &srcl);
662 const char *p = luaL_checkstring(L, 2);
663 int tr = lua_type(L, 3);
664 int max_s = luaL_optint(L, 4, (int)(srcl+1));
665 int anchor = (*p == '^') ? (p++, 1) : 0;
666 int n = 0;
667 MatchState ms;
668 luaL_Buffer b;
669 if (!(tr == LUA_TNUMBER || tr == LUA_TSTRING ||
670 tr == LUA_TFUNCTION || tr == LUA_TTABLE))
671 lj_err_arg(L, 3, LJ_ERR_NOSFT);
672 luaL_buffinit(L, &b);
673 ms.L = L;
674 ms.src_init = src;
675 ms.src_end = src+srcl;
676 while (n < max_s) {
677 const char *e;
678 ms.level = ms.depth = 0;
679 e = match(&ms, src, p);
680 if (e) {
681 n++;
682 add_value(&ms, &b, src, e);
683 }
684 if (e && e>src) /* non empty match? */
685 src = e; /* skip it */
686 else if (src < ms.src_end)
687 luaL_addchar(&b, *src++);
688 else
689 break;
690 if (anchor)
691 break;
692 }
693 luaL_addlstring(&b, src, (size_t)(ms.src_end-src));
694 luaL_pushresult(&b);
695 lua_pushinteger(L, n); /* number of substitutions */
696 return 2;
697}
698
699/* ------------------------------------------------------------------------ */
700
701/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
702#define MAX_FMTITEM 512
703/* valid flags in a format specification */
704#define FMT_FLAGS "-+ #0"
705/*
706** maximum size of each format specification (such as '%-099.99d')
707** (+10 accounts for %99.99x plus margin of error)
708*/
709#define MAX_FMTSPEC (sizeof(FMT_FLAGS) + sizeof(LUA_INTFRMLEN) + 10)
710
711static void addquoted(lua_State *L, luaL_Buffer *b, int arg)
712{
713 GCstr *str = lj_lib_checkstr(L, arg);
714 int32_t len = (int32_t)str->len;
715 const char *s = strdata(str);
716 luaL_addchar(b, '"');
717 while (len--) {
718 uint32_t c = uchar(*s);
719 if (c == '"' || c == '\\' || c == '\n') {
720 luaL_addchar(b, '\\');
721 } else if (lj_char_iscntrl(c)) { /* This can only be 0-31 or 127. */
722 uint32_t d;
723 luaL_addchar(b, '\\');
724 if (c >= 100 || lj_char_isdigit(uchar(s[1]))) {
725 luaL_addchar(b, '0'+(c >= 100)); if (c >= 100) c -= 100;
726 goto tens;
727 } else if (c >= 10) {
728 tens:
729 d = (c * 205) >> 11; c -= d * 10; luaL_addchar(b, '0'+d);
730 }
731 c += '0';
732 }
733 luaL_addchar(b, c);
734 s++;
735 }
736 luaL_addchar(b, '"');
737}
738
739static const char *scanformat(lua_State *L, const char *strfrmt, char *form)
740{
741 const char *p = strfrmt;
742 while (*p != '\0' && strchr(FMT_FLAGS, *p) != NULL) p++; /* skip flags */
743 if ((size_t)(p - strfrmt) >= sizeof(FMT_FLAGS))
744 lj_err_caller(L, LJ_ERR_STRFMTR);
745 if (lj_char_isdigit(uchar(*p))) p++; /* skip width */
746 if (lj_char_isdigit(uchar(*p))) p++; /* (2 digits at most) */
747 if (*p == '.') {
748 p++;
749 if (lj_char_isdigit(uchar(*p))) p++; /* skip precision */
750 if (lj_char_isdigit(uchar(*p))) p++; /* (2 digits at most) */
751 }
752 if (lj_char_isdigit(uchar(*p)))
753 lj_err_caller(L, LJ_ERR_STRFMTW);
754 *(form++) = '%';
755 strncpy(form, strfrmt, (size_t)(p - strfrmt + 1));
756 form += p - strfrmt + 1;
757 *form = '\0';
758 return p;
759}
760
761static void addintlen(char *form)
762{
763 size_t l = strlen(form);
764 char spec = form[l - 1];
765 strcpy(form + l - 1, LUA_INTFRMLEN);
766 form[l + sizeof(LUA_INTFRMLEN) - 2] = spec;
767 form[l + sizeof(LUA_INTFRMLEN) - 1] = '\0';
768}
769
770static unsigned LUA_INTFRM_T num2intfrm(lua_State *L, int arg)
771{
772 if (sizeof(LUA_INTFRM_T) == 4) {
773 return (LUA_INTFRM_T)lj_lib_checkbit(L, arg);
774 } else {
775 cTValue *o;
776 lj_lib_checknumber(L, arg);
777 o = L->base+arg-1;
778 if (tvisint(o))
779 return (LUA_INTFRM_T)intV(o);
780 else
781 return (LUA_INTFRM_T)numV(o);
782 }
783}
784
785static unsigned LUA_INTFRM_T num2uintfrm(lua_State *L, int arg)
786{
787 if (sizeof(LUA_INTFRM_T) == 4) {
788 return (unsigned LUA_INTFRM_T)lj_lib_checkbit(L, arg);
789 } else {
790 cTValue *o;
791 lj_lib_checknumber(L, arg);
792 o = L->base+arg-1;
793 if (tvisint(o))
794 return (unsigned LUA_INTFRM_T)intV(o);
795 else if ((int32_t)o->u32.hi < 0)
796 return (unsigned LUA_INTFRM_T)(LUA_INTFRM_T)numV(o);
797 else
798 return (unsigned LUA_INTFRM_T)numV(o);
799 }
800}
801
802static GCstr *meta_tostring(lua_State *L, int arg)
803{
804 TValue *o = L->base+arg-1;
805 cTValue *mo;
806 lua_assert(o < L->top); /* Caller already checks for existence. */
807 if (LJ_LIKELY(tvisstr(o)))
808 return strV(o);
809 if (!tvisnil(mo = lj_meta_lookup(L, o, MM_tostring))) {
810 copyTV(L, L->top++, mo);
811 copyTV(L, L->top++, o);
812 lua_call(L, 1, 1);
813 L->top--;
814 if (tvisstr(L->top))
815 return strV(L->top);
816 o = L->base+arg-1;
817 copyTV(L, o, L->top);
818 }
819 if (tvisnumber(o)) {
820 return lj_str_fromnumber(L, o);
821 } else if (tvisnil(o)) {
822 return lj_str_newlit(L, "nil");
823 } else if (tvisfalse(o)) {
824 return lj_str_newlit(L, "false");
825 } else if (tvistrue(o)) {
826 return lj_str_newlit(L, "true");
827 } else {
828 if (tvisfunc(o) && isffunc(funcV(o)))
829 lj_str_pushf(L, "function: builtin#%d", funcV(o)->c.ffid);
830 else
831 lj_str_pushf(L, "%s: %p", lj_typename(o), lua_topointer(L, arg));
832 L->top--;
833 return strV(L->top);
834 }
835}
836
837LJLIB_CF(string_format)
838{
839 int arg = 1, top = (int)(L->top - L->base);
840 GCstr *fmt = lj_lib_checkstr(L, arg);
841 const char *strfrmt = strdata(fmt);
842 const char *strfrmt_end = strfrmt + fmt->len;
843 luaL_Buffer b;
844 luaL_buffinit(L, &b);
845 while (strfrmt < strfrmt_end) {
846 if (*strfrmt != L_ESC) {
847 luaL_addchar(&b, *strfrmt++);
848 } else if (*++strfrmt == L_ESC) {
849 luaL_addchar(&b, *strfrmt++); /* %% */
850 } else { /* format item */
851 char form[MAX_FMTSPEC]; /* to store the format (`%...') */
852 char buff[MAX_FMTITEM]; /* to store the formatted item */
853 if (++arg > top)
854 luaL_argerror(L, arg, lj_obj_typename[0]);
855 strfrmt = scanformat(L, strfrmt, form);
856 switch (*strfrmt++) {
857 case 'c':
858 sprintf(buff, form, lj_lib_checkint(L, arg));
859 break;
860 case 'd': case 'i':
861 addintlen(form);
862 sprintf(buff, form, num2intfrm(L, arg));
863 break;
864 case 'o': case 'u': case 'x': case 'X':
865 addintlen(form);
866 sprintf(buff, form, num2uintfrm(L, arg));
867 break;
868 case 'e': case 'E': case 'f': case 'g': case 'G': case 'a': case 'A': {
869 TValue tv;
870 tv.n = lj_lib_checknum(L, arg);
871 if (LJ_UNLIKELY((tv.u32.hi << 1) >= 0xffe00000)) {
872 /* Canonicalize output of non-finite values. */
873 char *p, nbuf[LJ_STR_NUMBUF];
874 size_t len = lj_str_bufnum(nbuf, &tv);
875 if (strfrmt[-1] < 'a') {
876 nbuf[len-3] = nbuf[len-3] - 0x20;
877 nbuf[len-2] = nbuf[len-2] - 0x20;
878 nbuf[len-1] = nbuf[len-1] - 0x20;
879 }
880 nbuf[len] = '\0';
881 for (p = form; *p < 'A' && *p != '.'; p++) ;
882 *p++ = 's'; *p = '\0';
883 sprintf(buff, form, nbuf);
884 break;
885 }
886 sprintf(buff, form, (double)tv.n);
887 break;
888 }
889 case 'q':
890 addquoted(L, &b, arg);
891 continue;
892 case 'p':
893 lj_str_pushf(L, "%p", lua_topointer(L, arg));
894 luaL_addvalue(&b);
895 continue;
896 case 's': {
897 GCstr *str = meta_tostring(L, arg);
898 if (!strchr(form, '.') && str->len >= 100) {
899 /* no precision and string is too long to be formatted;
900 keep original string */
901 setstrV(L, L->top++, str);
902 luaL_addvalue(&b);
903 continue;
904 }
905 sprintf(buff, form, strdata(str));
906 break;
907 }
908 default:
909 lj_err_callerv(L, LJ_ERR_STRFMTO, *(strfrmt -1));
910 break;
911 }
912 luaL_addlstring(&b, buff, strlen(buff));
913 }
914 }
915 luaL_pushresult(&b);
916 return 1;
917}
918
919/* ------------------------------------------------------------------------ */
920
921#include "lj_libdef.h"
922
923LUALIB_API int luaopen_string(lua_State *L)
924{
925 GCtab *mt;
926 global_State *g;
927 LJ_LIB_REG(L, LUA_STRLIBNAME, string);
928#if defined(LUA_COMPAT_GFIND) && !LJ_52
929 lua_getfield(L, -1, "gmatch");
930 lua_setfield(L, -2, "gfind");
931#endif
932 mt = lj_tab_new(L, 0, 1);
933 /* NOBARRIER: basemt is a GC root. */
934 g = G(L);
935 setgcref(basemt_it(g, LJ_TSTR), obj2gco(mt));
936 settabV(L, lj_tab_setstr(L, mt, mmname_str(g, MM_index)), tabV(L->top-1));
937 mt->nomm = (uint8_t)(~(1u<<MM_index));
938 return 1;
939}
940
941