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comparison src/lua/lstrlib.c @ 11:27763b933818

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raise lua sources up one level
author Robert McIntyre <rlm@mit.edu>
date Sat, 03 Mar 2012 11:07:39 -0600
parents src/lua/src/lstrlib.c@f9f4f1b99eed
children
comparison
equal deleted inserted replaced
10:48b74a4e4692 11:27763b933818
1 /*
2 ** $Id: lstrlib.c,v 1.132.1.4 2008/07/11 17:27:21 roberto Exp $
3 ** Standard library for string operations and pattern-matching
4 ** See Copyright Notice in lua.h
5 */
6
7
8 #include <ctype.h>
9 #include <stddef.h>
10 #include <stdio.h>
11 #include <stdlib.h>
12 #include <string.h>
13
14 #define lstrlib_c
15 #define LUA_LIB
16
17 #include "lua.h"
18
19 #include "lauxlib.h"
20 #include "lualib.h"
21
22
23 /* macro to `unsign' a character */
24 #define uchar(c) ((unsigned char)(c))
25
26
27
28 static int str_len (lua_State *L) {
29 size_t l;
30 luaL_checklstring(L, 1, &l);
31 lua_pushinteger(L, l);
32 return 1;
33 }
34
35
36 static ptrdiff_t posrelat (ptrdiff_t pos, size_t len) {
37 /* relative string position: negative means back from end */
38 if (pos < 0) pos += (ptrdiff_t)len + 1;
39 return (pos >= 0) ? pos : 0;
40 }
41
42
43 static int str_sub (lua_State *L) {
44 size_t l;
45 const char *s = luaL_checklstring(L, 1, &l);
46 ptrdiff_t start = posrelat(luaL_checkinteger(L, 2), l);
47 ptrdiff_t end = posrelat(luaL_optinteger(L, 3, -1), l);
48 if (start < 1) start = 1;
49 if (end > (ptrdiff_t)l) end = (ptrdiff_t)l;
50 if (start <= end)
51 lua_pushlstring(L, s+start-1, end-start+1);
52 else lua_pushliteral(L, "");
53 return 1;
54 }
55
56
57 static int str_reverse (lua_State *L) {
58 size_t l;
59 luaL_Buffer b;
60 const char *s = luaL_checklstring(L, 1, &l);
61 luaL_buffinit(L, &b);
62 while (l--) luaL_addchar(&b, s[l]);
63 luaL_pushresult(&b);
64 return 1;
65 }
66
67
68 static int str_lower (lua_State *L) {
69 size_t l;
70 size_t i;
71 luaL_Buffer b;
72 const char *s = luaL_checklstring(L, 1, &l);
73 luaL_buffinit(L, &b);
74 for (i=0; i<l; i++)
75 luaL_addchar(&b, tolower(uchar(s[i])));
76 luaL_pushresult(&b);
77 return 1;
78 }
79
80
81 static int str_upper (lua_State *L) {
82 size_t l;
83 size_t i;
84 luaL_Buffer b;
85 const char *s = luaL_checklstring(L, 1, &l);
86 luaL_buffinit(L, &b);
87 for (i=0; i<l; i++)
88 luaL_addchar(&b, toupper(uchar(s[i])));
89 luaL_pushresult(&b);
90 return 1;
91 }
92
93 static int str_rep (lua_State *L) {
94 size_t l;
95 luaL_Buffer b;
96 const char *s = luaL_checklstring(L, 1, &l);
97 int n = luaL_checkint(L, 2);
98 luaL_buffinit(L, &b);
99 while (n-- > 0)
100 luaL_addlstring(&b, s, l);
101 luaL_pushresult(&b);
102 return 1;
103 }
104
105
106 static int str_byte (lua_State *L) {
107 size_t l;
108 const char *s = luaL_checklstring(L, 1, &l);
109 ptrdiff_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
110 ptrdiff_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
111 int n, i;
112 if (posi <= 0) posi = 1;
113 if ((size_t)pose > l) pose = l;
114 if (posi > pose) return 0; /* empty interval; return no values */
115 n = (int)(pose - posi + 1);
116 if (posi + n <= pose) /* overflow? */
117 luaL_error(L, "string slice too long");
118 luaL_checkstack(L, n, "string slice too long");
119 for (i=0; i<n; i++)
120 lua_pushinteger(L, uchar(s[posi+i-1]));
121 return n;
122 }
123
124
125 static int str_char (lua_State *L) {
126 int n = lua_gettop(L); /* number of arguments */
127 int i;
128 luaL_Buffer b;
129 luaL_buffinit(L, &b);
130 for (i=1; i<=n; i++) {
131 int c = luaL_checkint(L, i);
132 luaL_argcheck(L, uchar(c) == c, i, "invalid value");
133 luaL_addchar(&b, uchar(c));
134 }
135 luaL_pushresult(&b);
136 return 1;
137 }
138
139
140 static int writer (lua_State *L, const void* b, size_t size, void* B) {
141 (void)L;
142 luaL_addlstring((luaL_Buffer*) B, (const char *)b, size);
143 return 0;
144 }
145
146
147 static int str_dump (lua_State *L) {
148 luaL_Buffer b;
149 luaL_checktype(L, 1, LUA_TFUNCTION);
150 lua_settop(L, 1);
151 luaL_buffinit(L,&b);
152 if (lua_dump(L, writer, &b) != 0)
153 luaL_error(L, "unable to dump given function");
154 luaL_pushresult(&b);
155 return 1;
156 }
157
158
159
160 /*
161 ** {======================================================
162 ** PATTERN MATCHING
163 ** =======================================================
164 */
165
166
167 #define CAP_UNFINISHED (-1)
168 #define CAP_POSITION (-2)
169
170 typedef struct MatchState {
171 const char *src_init; /* init of source string */
172 const char *src_end; /* end (`\0') of source string */
173 lua_State *L;
174 int level; /* total number of captures (finished or unfinished) */
175 struct {
176 const char *init;
177 ptrdiff_t len;
178 } capture[LUA_MAXCAPTURES];
179 } MatchState;
180
181
182 #define L_ESC '%'
183 #define SPECIALS "^$*+?.([%-"
184
185
186 static int check_capture (MatchState *ms, int l) {
187 l -= '1';
188 if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
189 return luaL_error(ms->L, "invalid capture index");
190 return l;
191 }
192
193
194 static int capture_to_close (MatchState *ms) {
195 int level = ms->level;
196 for (level--; level>=0; level--)
197 if (ms->capture[level].len == CAP_UNFINISHED) return level;
198 return luaL_error(ms->L, "invalid pattern capture");
199 }
200
201
202 static const char *classend (MatchState *ms, const char *p) {
203 switch (*p++) {
204 case L_ESC: {
205 if (*p == '\0')
206 luaL_error(ms->L, "malformed pattern (ends with " LUA_QL("%%") ")");
207 return p+1;
208 }
209 case '[': {
210 if (*p == '^') p++;
211 do { /* look for a `]' */
212 if (*p == '\0')
213 luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")");
214 if (*(p++) == L_ESC && *p != '\0')
215 p++; /* skip escapes (e.g. `%]') */
216 } while (*p != ']');
217 return p+1;
218 }
219 default: {
220 return p;
221 }
222 }
223 }
224
225
226 static int match_class (int c, int cl) {
227 int res;
228 switch (tolower(cl)) {
229 case 'a' : res = isalpha(c); break;
230 case 'c' : res = iscntrl(c); break;
231 case 'd' : res = isdigit(c); break;
232 case 'l' : res = islower(c); break;
233 case 'p' : res = ispunct(c); break;
234 case 's' : res = isspace(c); break;
235 case 'u' : res = isupper(c); break;
236 case 'w' : res = isalnum(c); break;
237 case 'x' : res = isxdigit(c); break;
238 case 'z' : res = (c == 0); break;
239 default: return (cl == c);
240 }
241 return (islower(cl) ? res : !res);
242 }
243
244
245 static int matchbracketclass (int c, const char *p, const char *ec) {
246 int sig = 1;
247 if (*(p+1) == '^') {
248 sig = 0;
249 p++; /* skip the `^' */
250 }
251 while (++p < ec) {
252 if (*p == L_ESC) {
253 p++;
254 if (match_class(c, uchar(*p)))
255 return sig;
256 }
257 else if ((*(p+1) == '-') && (p+2 < ec)) {
258 p+=2;
259 if (uchar(*(p-2)) <= c && c <= uchar(*p))
260 return sig;
261 }
262 else if (uchar(*p) == c) return sig;
263 }
264 return !sig;
265 }
266
267
268 static int singlematch (int c, const char *p, const char *ep) {
269 switch (*p) {
270 case '.': return 1; /* matches any char */
271 case L_ESC: return match_class(c, uchar(*(p+1)));
272 case '[': return matchbracketclass(c, p, ep-1);
273 default: return (uchar(*p) == c);
274 }
275 }
276
277
278 static const char *match (MatchState *ms, const char *s, const char *p);
279
280
281 static const char *matchbalance (MatchState *ms, const char *s,
282 const char *p) {
283 if (*p == 0 || *(p+1) == 0)
284 luaL_error(ms->L, "unbalanced pattern");
285 if (*s != *p) return NULL;
286 else {
287 int b = *p;
288 int e = *(p+1);
289 int cont = 1;
290 while (++s < ms->src_end) {
291 if (*s == e) {
292 if (--cont == 0) return s+1;
293 }
294 else if (*s == b) cont++;
295 }
296 }
297 return NULL; /* string ends out of balance */
298 }
299
300
301 static const char *max_expand (MatchState *ms, const char *s,
302 const char *p, const char *ep) {
303 ptrdiff_t i = 0; /* counts maximum expand for item */
304 while ((s+i)<ms->src_end && singlematch(uchar(*(s+i)), p, ep))
305 i++;
306 /* keeps trying to match with the maximum repetitions */
307 while (i>=0) {
308 const char *res = match(ms, (s+i), ep+1);
309 if (res) return res;
310 i--; /* else didn't match; reduce 1 repetition to try again */
311 }
312 return NULL;
313 }
314
315
316 static const char *min_expand (MatchState *ms, const char *s,
317 const char *p, const char *ep) {
318 for (;;) {
319 const char *res = match(ms, s, ep+1);
320 if (res != NULL)
321 return res;
322 else if (s<ms->src_end && singlematch(uchar(*s), p, ep))
323 s++; /* try with one more repetition */
324 else return NULL;
325 }
326 }
327
328
329 static const char *start_capture (MatchState *ms, const char *s,
330 const char *p, int what) {
331 const char *res;
332 int level = ms->level;
333 if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
334 ms->capture[level].init = s;
335 ms->capture[level].len = what;
336 ms->level = level+1;
337 if ((res=match(ms, s, p)) == NULL) /* match failed? */
338 ms->level--; /* undo capture */
339 return res;
340 }
341
342
343 static const char *end_capture (MatchState *ms, const char *s,
344 const char *p) {
345 int l = capture_to_close(ms);
346 const char *res;
347 ms->capture[l].len = s - ms->capture[l].init; /* close capture */
348 if ((res = match(ms, s, p)) == NULL) /* match failed? */
349 ms->capture[l].len = CAP_UNFINISHED; /* undo capture */
350 return res;
351 }
352
353
354 static const char *match_capture (MatchState *ms, const char *s, int l) {
355 size_t len;
356 l = check_capture(ms, l);
357 len = ms->capture[l].len;
358 if ((size_t)(ms->src_end-s) >= len &&
359 memcmp(ms->capture[l].init, s, len) == 0)
360 return s+len;
361 else return NULL;
362 }
363
364
365 static const char *match (MatchState *ms, const char *s, const char *p) {
366 init: /* using goto's to optimize tail recursion */
367 switch (*p) {
368 case '(': { /* start capture */
369 if (*(p+1) == ')') /* position capture? */
370 return start_capture(ms, s, p+2, CAP_POSITION);
371 else
372 return start_capture(ms, s, p+1, CAP_UNFINISHED);
373 }
374 case ')': { /* end capture */
375 return end_capture(ms, s, p+1);
376 }
377 case L_ESC: {
378 switch (*(p+1)) {
379 case 'b': { /* balanced string? */
380 s = matchbalance(ms, s, p+2);
381 if (s == NULL) return NULL;
382 p+=4; goto init; /* else return match(ms, s, p+4); */
383 }
384 case 'f': { /* frontier? */
385 const char *ep; char previous;
386 p += 2;
387 if (*p != '[')
388 luaL_error(ms->L, "missing " LUA_QL("[") " after "
389 LUA_QL("%%f") " in pattern");
390 ep = classend(ms, p); /* points to what is next */
391 previous = (s == ms->src_init) ? '\0' : *(s-1);
392 if (matchbracketclass(uchar(previous), p, ep-1) ||
393 !matchbracketclass(uchar(*s), p, ep-1)) return NULL;
394 p=ep; goto init; /* else return match(ms, s, ep); */
395 }
396 default: {
397 if (isdigit(uchar(*(p+1)))) { /* capture results (%0-%9)? */
398 s = match_capture(ms, s, uchar(*(p+1)));
399 if (s == NULL) return NULL;
400 p+=2; goto init; /* else return match(ms, s, p+2) */
401 }
402 goto dflt; /* case default */
403 }
404 }
405 }
406 case '\0': { /* end of pattern */
407 return s; /* match succeeded */
408 }
409 case '$': {
410 if (*(p+1) == '\0') /* is the `$' the last char in pattern? */
411 return (s == ms->src_end) ? s : NULL; /* check end of string */
412 else goto dflt;
413 }
414 default: dflt: { /* it is a pattern item */
415 const char *ep = classend(ms, p); /* points to what is next */
416 int m = s<ms->src_end && singlematch(uchar(*s), p, ep);
417 switch (*ep) {
418 case '?': { /* optional */
419 const char *res;
420 if (m && ((res=match(ms, s+1, ep+1)) != NULL))
421 return res;
422 p=ep+1; goto init; /* else return match(ms, s, ep+1); */
423 }
424 case '*': { /* 0 or more repetitions */
425 return max_expand(ms, s, p, ep);
426 }
427 case '+': { /* 1 or more repetitions */
428 return (m ? max_expand(ms, s+1, p, ep) : NULL);
429 }
430 case '-': { /* 0 or more repetitions (minimum) */
431 return min_expand(ms, s, p, ep);
432 }
433 default: {
434 if (!m) return NULL;
435 s++; p=ep; goto init; /* else return match(ms, s+1, ep); */
436 }
437 }
438 }
439 }
440 }
441
442
443
444 static const char *lmemfind (const char *s1, size_t l1,
445 const char *s2, size_t l2) {
446 if (l2 == 0) return s1; /* empty strings are everywhere */
447 else if (l2 > l1) return NULL; /* avoids a negative `l1' */
448 else {
449 const char *init; /* to search for a `*s2' inside `s1' */
450 l2--; /* 1st char will be checked by `memchr' */
451 l1 = l1-l2; /* `s2' cannot be found after that */
452 while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
453 init++; /* 1st char is already checked */
454 if (memcmp(init, s2+1, l2) == 0)
455 return init-1;
456 else { /* correct `l1' and `s1' to try again */
457 l1 -= init-s1;
458 s1 = init;
459 }
460 }
461 return NULL; /* not found */
462 }
463 }
464
465
466 static void push_onecapture (MatchState *ms, int i, const char *s,
467 const char *e) {
468 if (i >= ms->level) {
469 if (i == 0) /* ms->level == 0, too */
470 lua_pushlstring(ms->L, s, e - s); /* add whole match */
471 else
472 luaL_error(ms->L, "invalid capture index");
473 }
474 else {
475 ptrdiff_t l = ms->capture[i].len;
476 if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
477 if (l == CAP_POSITION)
478 lua_pushinteger(ms->L, ms->capture[i].init - ms->src_init + 1);
479 else
480 lua_pushlstring(ms->L, ms->capture[i].init, l);
481 }
482 }
483
484
485 static int push_captures (MatchState *ms, const char *s, const char *e) {
486 int i;
487 int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
488 luaL_checkstack(ms->L, nlevels, "too many captures");
489 for (i = 0; i < nlevels; i++)
490 push_onecapture(ms, i, s, e);
491 return nlevels; /* number of strings pushed */
492 }
493
494
495 static int str_find_aux (lua_State *L, int find) {
496 size_t l1, l2;
497 const char *s = luaL_checklstring(L, 1, &l1);
498 const char *p = luaL_checklstring(L, 2, &l2);
499 ptrdiff_t init = posrelat(luaL_optinteger(L, 3, 1), l1) - 1;
500 if (init < 0) init = 0;
501 else if ((size_t)(init) > l1) init = (ptrdiff_t)l1;
502 if (find && (lua_toboolean(L, 4) || /* explicit request? */
503 strpbrk(p, SPECIALS) == NULL)) { /* or no special characters? */
504 /* do a plain search */
505 const char *s2 = lmemfind(s+init, l1-init, p, l2);
506 if (s2) {
507 lua_pushinteger(L, s2-s+1);
508 lua_pushinteger(L, s2-s+l2);
509 return 2;
510 }
511 }
512 else {
513 MatchState ms;
514 int anchor = (*p == '^') ? (p++, 1) : 0;
515 const char *s1=s+init;
516 ms.L = L;
517 ms.src_init = s;
518 ms.src_end = s+l1;
519 do {
520 const char *res;
521 ms.level = 0;
522 if ((res=match(&ms, s1, p)) != NULL) {
523 if (find) {
524 lua_pushinteger(L, s1-s+1); /* start */
525 lua_pushinteger(L, res-s); /* end */
526 return push_captures(&ms, NULL, 0) + 2;
527 }
528 else
529 return push_captures(&ms, s1, res);
530 }
531 } while (s1++ < ms.src_end && !anchor);
532 }
533 lua_pushnil(L); /* not found */
534 return 1;
535 }
536
537
538 static int str_find (lua_State *L) {
539 return str_find_aux(L, 1);
540 }
541
542
543 static int str_match (lua_State *L) {
544 return str_find_aux(L, 0);
545 }
546
547
548 static int gmatch_aux (lua_State *L) {
549 MatchState ms;
550 size_t ls;
551 const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
552 const char *p = lua_tostring(L, lua_upvalueindex(2));
553 const char *src;
554 ms.L = L;
555 ms.src_init = s;
556 ms.src_end = s+ls;
557 for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3));
558 src <= ms.src_end;
559 src++) {
560 const char *e;
561 ms.level = 0;
562 if ((e = match(&ms, src, p)) != NULL) {
563 lua_Integer newstart = e-s;
564 if (e == src) newstart++; /* empty match? go at least one position */
565 lua_pushinteger(L, newstart);
566 lua_replace(L, lua_upvalueindex(3));
567 return push_captures(&ms, src, e);
568 }
569 }
570 return 0; /* not found */
571 }
572
573
574 static int gmatch (lua_State *L) {
575 luaL_checkstring(L, 1);
576 luaL_checkstring(L, 2);
577 lua_settop(L, 2);
578 lua_pushinteger(L, 0);
579 lua_pushcclosure(L, gmatch_aux, 3);
580 return 1;
581 }
582
583
584 static int gfind_nodef (lua_State *L) {
585 return luaL_error(L, LUA_QL("string.gfind") " was renamed to "
586 LUA_QL("string.gmatch"));
587 }
588
589
590 static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
591 const char *e) {
592 size_t l, i;
593 const char *news = lua_tolstring(ms->L, 3, &l);
594 for (i = 0; i < l; i++) {
595 if (news[i] != L_ESC)
596 luaL_addchar(b, news[i]);
597 else {
598 i++; /* skip ESC */
599 if (!isdigit(uchar(news[i])))
600 luaL_addchar(b, news[i]);
601 else if (news[i] == '0')
602 luaL_addlstring(b, s, e - s);
603 else {
604 push_onecapture(ms, news[i] - '1', s, e);
605 luaL_addvalue(b); /* add capture to accumulated result */
606 }
607 }
608 }
609 }
610
611
612 static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
613 const char *e) {
614 lua_State *L = ms->L;
615 switch (lua_type(L, 3)) {
616 case LUA_TNUMBER:
617 case LUA_TSTRING: {
618 add_s(ms, b, s, e);
619 return;
620 }
621 case LUA_TFUNCTION: {
622 int n;
623 lua_pushvalue(L, 3);
624 n = push_captures(ms, s, e);
625 lua_call(L, n, 1);
626 break;
627 }
628 case LUA_TTABLE: {
629 push_onecapture(ms, 0, s, e);
630 lua_gettable(L, 3);
631 break;
632 }
633 }
634 if (!lua_toboolean(L, -1)) { /* nil or false? */
635 lua_pop(L, 1);
636 lua_pushlstring(L, s, e - s); /* keep original text */
637 }
638 else if (!lua_isstring(L, -1))
639 luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
640 luaL_addvalue(b); /* add result to accumulator */
641 }
642
643
644 static int str_gsub (lua_State *L) {
645 size_t srcl;
646 const char *src = luaL_checklstring(L, 1, &srcl);
647 const char *p = luaL_checkstring(L, 2);
648 int tr = lua_type(L, 3);
649 int max_s = luaL_optint(L, 4, srcl+1);
650 int anchor = (*p == '^') ? (p++, 1) : 0;
651 int n = 0;
652 MatchState ms;
653 luaL_Buffer b;
654 luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
655 tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
656 "string/function/table expected");
657 luaL_buffinit(L, &b);
658 ms.L = L;
659 ms.src_init = src;
660 ms.src_end = src+srcl;
661 while (n < max_s) {
662 const char *e;
663 ms.level = 0;
664 e = match(&ms, src, p);
665 if (e) {
666 n++;
667 add_value(&ms, &b, src, e);
668 }
669 if (e && e>src) /* non empty match? */
670 src = e; /* skip it */
671 else if (src < ms.src_end)
672 luaL_addchar(&b, *src++);
673 else break;
674 if (anchor) break;
675 }
676 luaL_addlstring(&b, src, ms.src_end-src);
677 luaL_pushresult(&b);
678 lua_pushinteger(L, n); /* number of substitutions */
679 return 2;
680 }
681
682 /* }====================================================== */
683
684
685 /* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
686 #define MAX_ITEM 512
687 /* valid flags in a format specification */
688 #define FLAGS "-+ #0"
689 /*
690 ** maximum size of each format specification (such as '%-099.99d')
691 ** (+10 accounts for %99.99x plus margin of error)
692 */
693 #define MAX_FORMAT (sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10)
694
695
696 static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
697 size_t l;
698 const char *s = luaL_checklstring(L, arg, &l);
699 luaL_addchar(b, '"');
700 while (l--) {
701 switch (*s) {
702 case '"': case '\\': case '\n': {
703 luaL_addchar(b, '\\');
704 luaL_addchar(b, *s);
705 break;
706 }
707 case '\r': {
708 luaL_addlstring(b, "\\r", 2);
709 break;
710 }
711 case '\0': {
712 luaL_addlstring(b, "\\000", 4);
713 break;
714 }
715 default: {
716 luaL_addchar(b, *s);
717 break;
718 }
719 }
720 s++;
721 }
722 luaL_addchar(b, '"');
723 }
724
725 static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
726 const char *p = strfrmt;
727 while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++; /* skip flags */
728 if ((size_t)(p - strfrmt) >= sizeof(FLAGS))
729 luaL_error(L, "invalid format (repeated flags)");
730 if (isdigit(uchar(*p))) p++; /* skip width */
731 if (isdigit(uchar(*p))) p++; /* (2 digits at most) */
732 if (*p == '.') {
733 p++;
734 if (isdigit(uchar(*p))) p++; /* skip precision */
735 if (isdigit(uchar(*p))) p++; /* (2 digits at most) */
736 }
737 if (isdigit(uchar(*p)))
738 luaL_error(L, "invalid format (width or precision too long)");
739 *(form++) = '%';
740 strncpy(form, strfrmt, p - strfrmt + 1);
741 form += p - strfrmt + 1;
742 *form = '\0';
743 return p;
744 }
745
746
747 static void addintlen (char *form) {
748 size_t l = strlen(form);
749 char spec = form[l - 1];
750 strcpy(form + l - 1, LUA_INTFRMLEN);
751 form[l + sizeof(LUA_INTFRMLEN) - 2] = spec;
752 form[l + sizeof(LUA_INTFRMLEN) - 1] = '\0';
753 }
754
755
756 static int str_format (lua_State *L) {
757 int arg = 1;
758 size_t sfl;
759 const char *strfrmt = luaL_checklstring(L, arg, &sfl);
760 const char *strfrmt_end = strfrmt+sfl;
761 luaL_Buffer b;
762 luaL_buffinit(L, &b);
763 while (strfrmt < strfrmt_end) {
764 if (*strfrmt != L_ESC)
765 luaL_addchar(&b, *strfrmt++);
766 else if (*++strfrmt == L_ESC)
767 luaL_addchar(&b, *strfrmt++); /* %% */
768 else { /* format item */
769 char form[MAX_FORMAT]; /* to store the format (`%...') */
770 char buff[MAX_ITEM]; /* to store the formatted item */
771 arg++;
772 strfrmt = scanformat(L, strfrmt, form);
773 switch (*strfrmt++) {
774 case 'c': {
775 sprintf(buff, form, (int)luaL_checknumber(L, arg));
776 break;
777 }
778 case 'd': case 'i': {
779 addintlen(form);
780 sprintf(buff, form, (LUA_INTFRM_T)luaL_checknumber(L, arg));
781 break;
782 }
783 case 'o': case 'u': case 'x': case 'X': {
784 addintlen(form);
785 sprintf(buff, form, (unsigned LUA_INTFRM_T)luaL_checknumber(L, arg));
786 break;
787 }
788 case 'e': case 'E': case 'f':
789 case 'g': case 'G': {
790 sprintf(buff, form, (double)luaL_checknumber(L, arg));
791 break;
792 }
793 case 'q': {
794 addquoted(L, &b, arg);
795 continue; /* skip the 'addsize' at the end */
796 }
797 case 's': {
798 size_t l;
799 const char *s = luaL_checklstring(L, arg, &l);
800 if (!strchr(form, '.') && l >= 100) {
801 /* no precision and string is too long to be formatted;
802 keep original string */
803 lua_pushvalue(L, arg);
804 luaL_addvalue(&b);
805 continue; /* skip the `addsize' at the end */
806 }
807 else {
808 sprintf(buff, form, s);
809 break;
810 }
811 }
812 default: { /* also treat cases `pnLlh' */
813 return luaL_error(L, "invalid option " LUA_QL("%%%c") " to "
814 LUA_QL("format"), *(strfrmt - 1));
815 }
816 }
817 luaL_addlstring(&b, buff, strlen(buff));
818 }
819 }
820 luaL_pushresult(&b);
821 return 1;
822 }
823
824
825 static const luaL_Reg strlib[] = {
826 {"byte", str_byte},
827 {"char", str_char},
828 {"dump", str_dump},
829 {"find", str_find},
830 {"format", str_format},
831 {"gfind", gfind_nodef},
832 {"gmatch", gmatch},
833 {"gsub", str_gsub},
834 {"len", str_len},
835 {"lower", str_lower},
836 {"match", str_match},
837 {"rep", str_rep},
838 {"reverse", str_reverse},
839 {"sub", str_sub},
840 {"upper", str_upper},
841 {NULL, NULL}
842 };
843
844
845 static void createmetatable (lua_State *L) {
846 lua_createtable(L, 0, 1); /* create metatable for strings */
847 lua_pushliteral(L, ""); /* dummy string */
848 lua_pushvalue(L, -2);
849 lua_setmetatable(L, -2); /* set string metatable */
850 lua_pop(L, 1); /* pop dummy string */
851 lua_pushvalue(L, -2); /* string library... */
852 lua_setfield(L, -2, "__index"); /* ...is the __index metamethod */
853 lua_pop(L, 1); /* pop metatable */
854 }
855
856
857 /*
858 ** Open string library
859 */
860 LUALIB_API int luaopen_string (lua_State *L) {
861 luaL_register(L, LUA_STRLIBNAME, strlib);
862 #if defined(LUA_COMPAT_GFIND)
863 lua_getfield(L, -1, "gmatch");
864 lua_setfield(L, -2, "gfind");
865 #endif
866 createmetatable(L);
867 return 1;
868 }
869