1 /*
2 ** $Id: lstrlib.c,v 1.178.1.1 2013/04/12 18:48:47 roberto Exp $
3 ** Standard library for string operations and pattern-matching
4 ** See Copyright Notice in lua.h
5 */
6
7
8 #include <sys/ctype.h>
9 #include <sys/zfs_context.h>
10
11 #define lstrlib_c
12 #define LUA_LIB
13
14 #include "lua.h"
15
16 #include "lauxlib.h"
17 #include "lualib.h"
18
19
20 /*
21 ** maximum number of captures that a pattern can do during
22 ** pattern-matching. This limit is arbitrary.
23 */
24 #if !defined(LUA_MAXCAPTURES)
25 #define LUA_MAXCAPTURES 32
26 #endif
27
28
29 /* macro to `unsign' a character */
30 #define uchar(c) ((unsigned char)(c))
31
32 /*
33 * PATCHED: add missing character macros.
34 */
35 #define tolower(C) (((C) >= 'A' && (C) <= 'Z') ? (C) - 'A' + 'a' : (C))
36 #define toupper(C) (((C) >= 'a' && (C) <= 'z') ? (C) - 'a' + 'A': (C))
37 #define isgraph(C) ((C) >= 0x21 && (C) <= 0x7E)
38 #define ispunct(C) (((C) >= 0x21 && (C) <= 0x2F) || \
39 ((C) >= 0x3A && (C) <= 0x40) || \
40 ((C) >= 0x5B && (C) <= 0x60) || \
41 ((C) >= 0x7B && (C) <= 0x7E))
42
43 /*
44 * The provided version of sprintf returns a char *, but str_format expects
45 * it to return the number of characters printed. This version has the expected
46 * behavior.
47 */
str_sprintf(char * buf,const char * fmt,...)48 static size_t str_sprintf(char *buf, const char *fmt, ...) {
49 va_list args;
50 size_t len;
51
52 va_start(args, fmt);
53 len = vsnprintf(buf, INT_MAX, fmt, args);
54 va_end(args);
55
56 return len;
57 }
58
59
str_len(lua_State * L)60 static int str_len (lua_State *L) {
61 size_t l;
62 luaL_checklstring(L, 1, &l);
63 lua_pushinteger(L, (lua_Integer)l);
64 return 1;
65 }
66
67
68 /* translate a relative string position: negative means back from end */
posrelat(ptrdiff_t pos,size_t len)69 static size_t posrelat (ptrdiff_t pos, size_t len) {
70 if (pos >= 0) return (size_t)pos;
71 else if (0u - (size_t)pos > len) return 0;
72 else return len - ((size_t)-pos) + 1;
73 }
74
75
str_sub(lua_State * L)76 static int str_sub (lua_State *L) {
77 size_t l;
78 const char *s = luaL_checklstring(L, 1, &l);
79 size_t start = posrelat(luaL_checkinteger(L, 2), l);
80 size_t end = posrelat(luaL_optinteger(L, 3, -1), l);
81 if (start < 1) start = 1;
82 if (end > l) end = l;
83 if (start <= end)
84 lua_pushlstring(L, s + start - 1, end - start + 1);
85 else lua_pushliteral(L, "");
86 return 1;
87 }
88
89
str_reverse(lua_State * L)90 static int str_reverse (lua_State *L) {
91 size_t l, i;
92 luaL_Buffer b;
93 const char *s = luaL_checklstring(L, 1, &l);
94 char *p = luaL_buffinitsize(L, &b, l);
95 for (i = 0; i < l; i++)
96 p[i] = s[l - i - 1];
97 luaL_pushresultsize(&b, l);
98 return 1;
99 }
100
101
str_lower(lua_State * L)102 static int str_lower (lua_State *L) {
103 size_t l;
104 size_t i;
105 luaL_Buffer b;
106 const char *s = luaL_checklstring(L, 1, &l);
107 char *p = luaL_buffinitsize(L, &b, l);
108 for (i=0; i<l; i++)
109 p[i] = tolower(uchar(s[i]));
110 luaL_pushresultsize(&b, l);
111 return 1;
112 }
113
114
str_upper(lua_State * L)115 static int str_upper (lua_State *L) {
116 size_t l;
117 size_t i;
118 luaL_Buffer b;
119 const char *s = luaL_checklstring(L, 1, &l);
120 char *p = luaL_buffinitsize(L, &b, l);
121 for (i=0; i<l; i++)
122 p[i] = toupper(uchar(s[i]));
123 luaL_pushresultsize(&b, l);
124 return 1;
125 }
126
127
128 /* reasonable limit to avoid arithmetic overflow */
129 #define MAXSIZE ((~(size_t)0) >> 1)
130
str_rep(lua_State * L)131 static int str_rep (lua_State *L) {
132 size_t l, lsep;
133 const char *s = luaL_checklstring(L, 1, &l);
134 int n = luaL_checkint(L, 2);
135 const char *sep = luaL_optlstring(L, 3, "", &lsep);
136 if (n <= 0) lua_pushliteral(L, "");
137 else if (l + lsep < l || l + lsep >= MAXSIZE / n) /* may overflow? */
138 return luaL_error(L, "resulting string too large");
139 else {
140 size_t totallen = n * l + (n - 1) * lsep;
141 luaL_Buffer b;
142 char *p = luaL_buffinitsize(L, &b, totallen);
143 while (n-- > 1) { /* first n-1 copies (followed by separator) */
144 memcpy(p, s, l * sizeof(char)); p += l;
145 if (lsep > 0) { /* avoid empty 'memcpy' (may be expensive) */
146 memcpy(p, sep, lsep * sizeof(char)); p += lsep;
147 }
148 }
149 memcpy(p, s, l * sizeof(char)); /* last copy (not followed by separator) */
150 luaL_pushresultsize(&b, totallen);
151 }
152 return 1;
153 }
154
155
str_byte(lua_State * L)156 static int str_byte (lua_State *L) {
157 size_t l;
158 const char *s = luaL_checklstring(L, 1, &l);
159 size_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
160 size_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
161 int n, i;
162 if (posi < 1) posi = 1;
163 if (pose > l) pose = l;
164 if (posi > pose) return 0; /* empty interval; return no values */
165 n = (int)(pose - posi + 1);
166 if (posi + n <= pose) /* (size_t -> int) overflow? */
167 return luaL_error(L, "string slice too long");
168 luaL_checkstack(L, n, "string slice too long");
169 for (i=0; i<n; i++)
170 lua_pushinteger(L, uchar(s[posi+i-1]));
171 return n;
172 }
173
174
str_char(lua_State * L)175 static int str_char (lua_State *L) {
176 int n = lua_gettop(L); /* number of arguments */
177 int i;
178 luaL_Buffer b;
179 char *p = luaL_buffinitsize(L, &b, n);
180 for (i=1; i<=n; i++) {
181 int c = luaL_checkint(L, i);
182 luaL_argcheck(L, uchar(c) == c, i, "value out of range");
183 p[i - 1] = uchar(c);
184 }
185 luaL_pushresultsize(&b, n);
186 return 1;
187 }
188
189
writer(lua_State * L,const void * b,size_t size,void * B)190 static int writer (lua_State *L, const void* b, size_t size, void* B) {
191 (void)L;
192 luaL_addlstring((luaL_Buffer*) B, (const char *)b, size);
193 return 0;
194 }
195
196
str_dump(lua_State * L)197 static int str_dump (lua_State *L) {
198 luaL_Buffer b;
199 luaL_checktype(L, 1, LUA_TFUNCTION);
200 lua_settop(L, 1);
201 luaL_buffinit(L,&b);
202 if (lua_dump(L, writer, &b) != 0)
203 return luaL_error(L, "unable to dump given function");
204 luaL_pushresult(&b);
205 return 1;
206 }
207
208
209
210 /*
211 ** {======================================================
212 ** PATTERN MATCHING
213 ** =======================================================
214 */
215
216
217 #define CAP_UNFINISHED (-1)
218 #define CAP_POSITION (-2)
219
220
221 typedef struct MatchState {
222 int matchdepth; /* control for recursive depth (to avoid C stack overflow) */
223 const char *src_init; /* init of source string */
224 const char *src_end; /* end ('\0') of source string */
225 const char *p_end; /* end ('\0') of pattern */
226 lua_State *L;
227 int level; /* total number of captures (finished or unfinished) */
228 struct {
229 const char *init;
230 ptrdiff_t len;
231 } capture[LUA_MAXCAPTURES];
232 } MatchState;
233
234
235 /* recursive function */
236 static const char *match (MatchState *ms, const char *s, const char *p);
237
238
239 /* maximum recursion depth for 'match' */
240 #if !defined(MAXCCALLS)
241 #define MAXCCALLS 200
242 #endif
243
244
245 #define L_ESC '%'
246 #define SPECIALS "^$*+?.([%-"
247
248
check_capture(MatchState * ms,int l)249 static int check_capture (MatchState *ms, int l) {
250 l -= '1';
251 if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
252 return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
253 return l;
254 }
255
256
capture_to_close(MatchState * ms)257 static int capture_to_close (MatchState *ms) {
258 int level = ms->level;
259 for (level--; level>=0; level--)
260 if (ms->capture[level].len == CAP_UNFINISHED) return level;
261 return luaL_error(ms->L, "invalid pattern capture");
262 }
263
264
classend(MatchState * ms,const char * p)265 static const char *classend (MatchState *ms, const char *p) {
266 switch (*p++) {
267 case L_ESC: {
268 if (p == ms->p_end)
269 luaL_error(ms->L, "malformed pattern (ends with " LUA_QL("%%") ")");
270 return p+1;
271 }
272 case '[': {
273 if (*p == '^') p++;
274 do { /* look for a `]' */
275 if (p == ms->p_end)
276 luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")");
277 if (*(p++) == L_ESC && p < ms->p_end)
278 p++; /* skip escapes (e.g. `%]') */
279 } while (*p != ']');
280 return p+1;
281 }
282 default: {
283 return p;
284 }
285 }
286 }
287
288
289 static int
iscntrl(int c)290 iscntrl(int c)
291 {
292 return ((c < 0x20) || (c == 0x7f));
293 }
294
295
match_class(int c,int cl)296 static int match_class (int c, int cl) {
297 int res;
298 switch (tolower(cl)) {
299 case 'a' : res = isalpha(c); break;
300 case 'c' : res = iscntrl(c); break;
301 case 'd' : res = isdigit(c); break;
302 case 'g' : res = isgraph(c); break;
303 case 'l' : res = islower(c); break;
304 case 'p' : res = ispunct(c); break;
305 case 's' : res = isspace(c); break;
306 case 'u' : res = isupper(c); break;
307 case 'w' : res = isalnum(c); break;
308 case 'x' : res = isxdigit(c); break;
309 case 'z' : res = (c == 0); break; /* deprecated option */
310 default: return (cl == c);
311 }
312 return (islower(cl) ? res : !res);
313 }
314
315
matchbracketclass(int c,const char * p,const char * ec)316 static int matchbracketclass (int c, const char *p, const char *ec) {
317 int sig = 1;
318 if (*(p+1) == '^') {
319 sig = 0;
320 p++; /* skip the `^' */
321 }
322 while (++p < ec) {
323 if (*p == L_ESC) {
324 p++;
325 if (match_class(c, uchar(*p)))
326 return sig;
327 }
328 else if ((*(p+1) == '-') && (p+2 < ec)) {
329 p+=2;
330 if (uchar(*(p-2)) <= c && c <= uchar(*p))
331 return sig;
332 }
333 else if (uchar(*p) == c) return sig;
334 }
335 return !sig;
336 }
337
338
singlematch(MatchState * ms,const char * s,const char * p,const char * ep)339 static int singlematch (MatchState *ms, const char *s, const char *p,
340 const char *ep) {
341 if (s >= ms->src_end)
342 return 0;
343 else {
344 int c = uchar(*s);
345 switch (*p) {
346 case '.': return 1; /* matches any char */
347 case L_ESC: return match_class(c, uchar(*(p+1)));
348 case '[': return matchbracketclass(c, p, ep-1);
349 default: return (uchar(*p) == c);
350 }
351 }
352 }
353
354
matchbalance(MatchState * ms,const char * s,const char * p)355 static const char *matchbalance (MatchState *ms, const char *s,
356 const char *p) {
357 if (p >= ms->p_end - 1)
358 luaL_error(ms->L, "malformed pattern "
359 "(missing arguments to " LUA_QL("%%b") ")");
360 if (*s != *p) return NULL;
361 else {
362 int b = *p;
363 int e = *(p+1);
364 int cont = 1;
365 while (++s < ms->src_end) {
366 if (*s == e) {
367 if (--cont == 0) return s+1;
368 }
369 else if (*s == b) cont++;
370 }
371 }
372 return NULL; /* string ends out of balance */
373 }
374
375
max_expand(MatchState * ms,const char * s,const char * p,const char * ep)376 static const char *max_expand (MatchState *ms, const char *s,
377 const char *p, const char *ep) {
378 ptrdiff_t i = 0; /* counts maximum expand for item */
379 while (singlematch(ms, s + i, p, ep))
380 i++;
381 /* keeps trying to match with the maximum repetitions */
382 while (i>=0) {
383 const char *res = match(ms, (s+i), ep+1);
384 if (res) return res;
385 i--; /* else didn't match; reduce 1 repetition to try again */
386 }
387 return NULL;
388 }
389
390
min_expand(MatchState * ms,const char * s,const char * p,const char * ep)391 static const char *min_expand (MatchState *ms, const char *s,
392 const char *p, const char *ep) {
393 for (;;) {
394 const char *res = match(ms, s, ep+1);
395 if (res != NULL)
396 return res;
397 else if (singlematch(ms, s, p, ep))
398 s++; /* try with one more repetition */
399 else return NULL;
400 }
401 }
402
403
start_capture(MatchState * ms,const char * s,const char * p,int what)404 static const char *start_capture (MatchState *ms, const char *s,
405 const char *p, int what) {
406 const char *res;
407 int level = ms->level;
408 if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
409 ms->capture[level].init = s;
410 ms->capture[level].len = what;
411 ms->level = level+1;
412 if ((res=match(ms, s, p)) == NULL) /* match failed? */
413 ms->level--; /* undo capture */
414 return res;
415 }
416
417
end_capture(MatchState * ms,const char * s,const char * p)418 static const char *end_capture (MatchState *ms, const char *s,
419 const char *p) {
420 int l = capture_to_close(ms);
421 const char *res;
422 ms->capture[l].len = s - ms->capture[l].init; /* close capture */
423 if ((res = match(ms, s, p)) == NULL) /* match failed? */
424 ms->capture[l].len = CAP_UNFINISHED; /* undo capture */
425 return res;
426 }
427
428
match_capture(MatchState * ms,const char * s,int l)429 static const char *match_capture (MatchState *ms, const char *s, int l) {
430 size_t len;
431 l = check_capture(ms, l);
432 len = ms->capture[l].len;
433 if ((size_t)(ms->src_end-s) >= len &&
434 memcmp(ms->capture[l].init, s, len) == 0)
435 return s+len;
436 else return NULL;
437 }
438
439
match(MatchState * ms,const char * s,const char * p)440 static const char *match (MatchState *ms, const char *s, const char *p) {
441 if (ms->matchdepth-- == 0)
442 luaL_error(ms->L, "pattern too complex");
443 init: /* using goto's to optimize tail recursion */
444 if (p != ms->p_end) { /* end of pattern? */
445 switch (*p) {
446 case '(': { /* start capture */
447 if (*(p + 1) == ')') /* position capture? */
448 s = start_capture(ms, s, p + 2, CAP_POSITION);
449 else
450 s = start_capture(ms, s, p + 1, CAP_UNFINISHED);
451 break;
452 }
453 case ')': { /* end capture */
454 s = end_capture(ms, s, p + 1);
455 break;
456 }
457 case '$': {
458 if ((p + 1) != ms->p_end) /* is the `$' the last char in pattern? */
459 goto dflt; /* no; go to default */
460 s = (s == ms->src_end) ? s : NULL; /* check end of string */
461 break;
462 }
463 case L_ESC: { /* escaped sequences not in the format class[*+?-]? */
464 switch (*(p + 1)) {
465 case 'b': { /* balanced string? */
466 s = matchbalance(ms, s, p + 2);
467 if (s != NULL) {
468 p += 4; goto init; /* return match(ms, s, p + 4); */
469 } /* else fail (s == NULL) */
470 break;
471 }
472 case 'f': { /* frontier? */
473 const char *ep; char previous;
474 p += 2;
475 if (*p != '[')
476 luaL_error(ms->L, "missing " LUA_QL("[") " after "
477 LUA_QL("%%f") " in pattern");
478 ep = classend(ms, p); /* points to what is next */
479 previous = (s == ms->src_init) ? '\0' : *(s - 1);
480 if (!matchbracketclass(uchar(previous), p, ep - 1) &&
481 matchbracketclass(uchar(*s), p, ep - 1)) {
482 p = ep; goto init; /* return match(ms, s, ep); */
483 }
484 s = NULL; /* match failed */
485 break;
486 }
487 case '0': case '1': case '2': case '3':
488 case '4': case '5': case '6': case '7':
489 case '8': case '9': { /* capture results (%0-%9)? */
490 s = match_capture(ms, s, uchar(*(p + 1)));
491 if (s != NULL) {
492 p += 2; goto init; /* return match(ms, s, p + 2) */
493 }
494 break;
495 }
496 default: goto dflt;
497 }
498 break;
499 }
500 default: dflt: { /* pattern class plus optional suffix */
501 const char *ep = classend(ms, p); /* points to optional suffix */
502 /* does not match at least once? */
503 if (!singlematch(ms, s, p, ep)) {
504 if (*ep == '*' || *ep == '?' || *ep == '-') { /* accept empty? */
505 p = ep + 1; goto init; /* return match(ms, s, ep + 1); */
506 }
507 else /* '+' or no suffix */
508 s = NULL; /* fail */
509 }
510 else { /* matched once */
511 switch (*ep) { /* handle optional suffix */
512 case '?': { /* optional */
513 const char *res;
514 if ((res = match(ms, s + 1, ep + 1)) != NULL)
515 s = res;
516 else {
517 p = ep + 1; goto init; /* else return match(ms, s, ep + 1); */
518 }
519 break;
520 }
521 case '+': /* 1 or more repetitions */
522 s++; /* 1 match already done */
523 /* FALLTHROUGH */
524 case '*': /* 0 or more repetitions */
525 s = max_expand(ms, s, p, ep);
526 break;
527 case '-': /* 0 or more repetitions (minimum) */
528 s = min_expand(ms, s, p, ep);
529 break;
530 default: /* no suffix */
531 s++; p = ep; goto init; /* return match(ms, s + 1, ep); */
532 }
533 }
534 break;
535 }
536 }
537 }
538 ms->matchdepth++;
539 return s;
540 }
541
542
543
lmemfind(const char * s1,size_t l1,const char * s2,size_t l2)544 static const char *lmemfind (const char *s1, size_t l1,
545 const char *s2, size_t l2) {
546 if (l2 == 0) return s1; /* empty strings are everywhere */
547 else if (l2 > l1) return NULL; /* avoids a negative `l1' */
548 else {
549 const char *init; /* to search for a `*s2' inside `s1' */
550 l2--; /* 1st char will be checked by `memchr' */
551 l1 = l1-l2; /* `s2' cannot be found after that */
552 while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
553 init++; /* 1st char is already checked */
554 if (memcmp(init, s2+1, l2) == 0)
555 return init-1;
556 else { /* correct `l1' and `s1' to try again */
557 l1 -= init-s1;
558 s1 = init;
559 }
560 }
561 return NULL; /* not found */
562 }
563 }
564
565
push_onecapture(MatchState * ms,int i,const char * s,const char * e)566 static void push_onecapture (MatchState *ms, int i, const char *s,
567 const char *e) {
568 if (i >= ms->level) {
569 if (i == 0) /* ms->level == 0, too */
570 lua_pushlstring(ms->L, s, e - s); /* add whole match */
571 else
572 luaL_error(ms->L, "invalid capture index");
573 }
574 else {
575 ptrdiff_t l = ms->capture[i].len;
576 if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
577 if (l == CAP_POSITION)
578 lua_pushinteger(ms->L, ms->capture[i].init - ms->src_init + 1);
579 else
580 lua_pushlstring(ms->L, ms->capture[i].init, l);
581 }
582 }
583
584
push_captures(MatchState * ms,const char * s,const char * e)585 static int push_captures (MatchState *ms, const char *s, const char *e) {
586 int i;
587 int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
588 luaL_checkstack(ms->L, nlevels, "too many captures");
589 for (i = 0; i < nlevels; i++)
590 push_onecapture(ms, i, s, e);
591 return nlevels; /* number of strings pushed */
592 }
593
594
595 /* check whether pattern has no special characters */
nospecials(const char * p,size_t l)596 static int nospecials (const char *p, size_t l) {
597 size_t upto = 0;
598 do {
599 if (strpbrk(p + upto, SPECIALS))
600 return 0; /* pattern has a special character */
601 upto += strlen(p + upto) + 1; /* may have more after \0 */
602 } while (upto <= l);
603 return 1; /* no special chars found */
604 }
605
606
str_find_aux(lua_State * L,int find)607 static int str_find_aux (lua_State *L, int find) {
608 size_t ls, lp;
609 const char *s = luaL_checklstring(L, 1, &ls);
610 const char *p = luaL_checklstring(L, 2, &lp);
611 size_t init = posrelat(luaL_optinteger(L, 3, 1), ls);
612 if (init < 1) init = 1;
613 else if (init > ls + 1) { /* start after string's end? */
614 lua_pushnil(L); /* cannot find anything */
615 return 1;
616 }
617 /* explicit request or no special characters? */
618 if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
619 /* do a plain search */
620 const char *s2 = lmemfind(s + init - 1, ls - init + 1, p, lp);
621 if (s2) {
622 lua_pushinteger(L, s2 - s + 1);
623 lua_pushinteger(L, s2 - s + lp);
624 return 2;
625 }
626 }
627 else {
628 MatchState ms;
629 const char *s1 = s + init - 1;
630 int anchor = (*p == '^');
631 if (anchor) {
632 p++; lp--; /* skip anchor character */
633 }
634 ms.L = L;
635 ms.matchdepth = MAXCCALLS;
636 ms.src_init = s;
637 ms.src_end = s + ls;
638 ms.p_end = p + lp;
639 do {
640 const char *res;
641 ms.level = 0;
642 lua_assert(ms.matchdepth == MAXCCALLS);
643 if ((res=match(&ms, s1, p)) != NULL) {
644 if (find) {
645 lua_pushinteger(L, s1 - s + 1); /* start */
646 lua_pushinteger(L, res - s); /* end */
647 return push_captures(&ms, NULL, 0) + 2;
648 }
649 else
650 return push_captures(&ms, s1, res);
651 }
652 } while (s1++ < ms.src_end && !anchor);
653 }
654 lua_pushnil(L); /* not found */
655 return 1;
656 }
657
658
str_find(lua_State * L)659 static int str_find (lua_State *L) {
660 return str_find_aux(L, 1);
661 }
662
663
str_match(lua_State * L)664 static int str_match (lua_State *L) {
665 return str_find_aux(L, 0);
666 }
667
668
gmatch_aux(lua_State * L)669 static int gmatch_aux (lua_State *L) {
670 MatchState ms;
671 size_t ls, lp;
672 const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
673 const char *p = lua_tolstring(L, lua_upvalueindex(2), &lp);
674 const char *src;
675 ms.L = L;
676 ms.matchdepth = MAXCCALLS;
677 ms.src_init = s;
678 ms.src_end = s+ls;
679 ms.p_end = p + lp;
680 for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3));
681 src <= ms.src_end;
682 src++) {
683 const char *e;
684 ms.level = 0;
685 lua_assert(ms.matchdepth == MAXCCALLS);
686 if ((e = match(&ms, src, p)) != NULL) {
687 lua_Integer newstart = e-s;
688 if (e == src) newstart++; /* empty match? go at least one position */
689 lua_pushinteger(L, newstart);
690 lua_replace(L, lua_upvalueindex(3));
691 return push_captures(&ms, src, e);
692 }
693 }
694 return 0; /* not found */
695 }
696
697
str_gmatch(lua_State * L)698 static int str_gmatch (lua_State *L) {
699 luaL_checkstring(L, 1);
700 luaL_checkstring(L, 2);
701 lua_settop(L, 2);
702 lua_pushinteger(L, 0);
703 lua_pushcclosure(L, gmatch_aux, 3);
704 return 1;
705 }
706
707
add_s(MatchState * ms,luaL_Buffer * b,const char * s,const char * e)708 static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
709 const char *e) {
710 size_t l, i;
711 const char *news = lua_tolstring(ms->L, 3, &l);
712 for (i = 0; i < l; i++) {
713 if (news[i] != L_ESC)
714 luaL_addchar(b, news[i]);
715 else {
716 i++; /* skip ESC */
717 if (!isdigit(uchar(news[i]))) {
718 if (news[i] != L_ESC)
719 luaL_error(ms->L, "invalid use of " LUA_QL("%c")
720 " in replacement string", L_ESC);
721 luaL_addchar(b, news[i]);
722 }
723 else if (news[i] == '0')
724 luaL_addlstring(b, s, e - s);
725 else {
726 push_onecapture(ms, news[i] - '1', s, e);
727 luaL_addvalue(b); /* add capture to accumulated result */
728 }
729 }
730 }
731 }
732
733
add_value(MatchState * ms,luaL_Buffer * b,const char * s,const char * e,int tr)734 static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
735 const char *e, int tr) {
736 lua_State *L = ms->L;
737 switch (tr) {
738 case LUA_TFUNCTION: {
739 int n;
740 lua_pushvalue(L, 3);
741 n = push_captures(ms, s, e);
742 lua_call(L, n, 1);
743 break;
744 }
745 case LUA_TTABLE: {
746 push_onecapture(ms, 0, s, e);
747 lua_gettable(L, 3);
748 break;
749 }
750 default: { /* LUA_TNUMBER or LUA_TSTRING */
751 add_s(ms, b, s, e);
752 return;
753 }
754 }
755 if (!lua_toboolean(L, -1)) { /* nil or false? */
756 lua_pop(L, 1);
757 lua_pushlstring(L, s, e - s); /* keep original text */
758 }
759 else if (!lua_isstring(L, -1))
760 luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
761 luaL_addvalue(b); /* add result to accumulator */
762 }
763
764
str_gsub(lua_State * L)765 static int str_gsub (lua_State *L) {
766 size_t srcl, lp;
767 const char *src = luaL_checklstring(L, 1, &srcl);
768 const char *p = luaL_checklstring(L, 2, &lp);
769 int tr = lua_type(L, 3);
770 size_t max_s = luaL_optinteger(L, 4, srcl+1);
771 int anchor = (*p == '^');
772 size_t n = 0;
773 MatchState ms;
774 luaL_Buffer b;
775 luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
776 tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
777 "string/function/table expected");
778 luaL_buffinit(L, &b);
779 if (anchor) {
780 p++; lp--; /* skip anchor character */
781 }
782 ms.L = L;
783 ms.matchdepth = MAXCCALLS;
784 ms.src_init = src;
785 ms.src_end = src+srcl;
786 ms.p_end = p + lp;
787 while (n < max_s) {
788 const char *e;
789 ms.level = 0;
790 lua_assert(ms.matchdepth == MAXCCALLS);
791 e = match(&ms, src, p);
792 if (e) {
793 n++;
794 add_value(&ms, &b, src, e, tr);
795 }
796 if (e && e>src) /* non empty match? */
797 src = e; /* skip it */
798 else if (src < ms.src_end)
799 luaL_addchar(&b, *src++);
800 else break;
801 if (anchor) break;
802 }
803 luaL_addlstring(&b, src, ms.src_end-src);
804 luaL_pushresult(&b);
805 lua_pushinteger(L, n); /* number of substitutions */
806 return 2;
807 }
808
809 /* }====================================================== */
810
811
812
813 /*
814 ** {======================================================
815 ** STRING FORMAT
816 ** =======================================================
817 */
818
819 /*
820 ** LUA_INTFRMLEN is the length modifier for integer conversions in
821 ** 'string.format'; LUA_INTFRM_T is the integer type corresponding to
822 ** the previous length
823 */
824 #if !defined(LUA_INTFRMLEN) /* { */
825 #if defined(LUA_USE_LONGLONG)
826
827 #define LUA_INTFRMLEN "ll"
828 #define LUA_INTFRM_T long long
829
830 #else
831
832 #define LUA_INTFRMLEN "l"
833 #define LUA_INTFRM_T long
834
835 #endif
836 #endif /* } */
837
838
839 /*
840 ** LUA_FLTFRMLEN is the length modifier for float conversions in
841 ** 'string.format'; LUA_FLTFRM_T is the float type corresponding to
842 ** the previous length
843 */
844 #if !defined(LUA_FLTFRMLEN)
845
846 #define LUA_FLTFRMLEN ""
847 #define LUA_FLTFRM_T double
848
849 #endif
850
851
852 /* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
853 #define MAX_ITEM 512
854 /* valid flags in a format specification */
855 #define FLAGS "-+ #0"
856 /*
857 ** maximum size of each format specification (such as '%-099.99d')
858 ** (+10 accounts for %99.99x plus margin of error)
859 */
860 #define MAX_FORMAT (sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10)
861
862
addquoted(lua_State * L,luaL_Buffer * b,int arg)863 static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
864 size_t l;
865 const char *s = luaL_checklstring(L, arg, &l);
866 luaL_addchar(b, '"');
867 while (l--) {
868 if (*s == '"' || *s == '\\' || *s == '\n') {
869 luaL_addchar(b, '\\');
870 luaL_addchar(b, *s);
871 }
872 else if (*s == '\0' || iscntrl(uchar(*s))) {
873 char buff[10];
874 if (!isdigit(uchar(*(s+1))))
875 sprintf(buff, "\\%d", (int)uchar(*s));
876 else
877 sprintf(buff, "\\%03d", (int)uchar(*s));
878 luaL_addstring(b, buff);
879 }
880 else
881 luaL_addchar(b, *s);
882 s++;
883 }
884 luaL_addchar(b, '"');
885 }
886
scanformat(lua_State * L,const char * strfrmt,char * form)887 static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
888 const char *p = strfrmt;
889 while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++; /* skip flags */
890 if ((size_t)(p - strfrmt) >= sizeof(FLAGS)/sizeof(char))
891 luaL_error(L, "invalid format (repeated flags)");
892 if (isdigit(uchar(*p))) p++; /* skip width */
893 if (isdigit(uchar(*p))) p++; /* (2 digits at most) */
894 if (*p == '.') {
895 p++;
896 if (isdigit(uchar(*p))) p++; /* skip precision */
897 if (isdigit(uchar(*p))) p++; /* (2 digits at most) */
898 }
899 if (isdigit(uchar(*p)))
900 luaL_error(L, "invalid format (width or precision too long)");
901 *(form++) = '%';
902 memcpy(form, strfrmt, (p - strfrmt + 1) * sizeof(char));
903 form += p - strfrmt + 1;
904 *form = '\0';
905 return p;
906 }
907
908
909 /*
910 ** add length modifier into formats
911 */
addlenmod(char * form,const char * lenmod)912 static void addlenmod (char *form, const char *lenmod) {
913 size_t l = strlen(form);
914 size_t lm = strlen(lenmod);
915 char spec = form[l - 1];
916 strcpy(form + l - 1, lenmod);
917 form[l + lm - 1] = spec;
918 form[l + lm] = '\0';
919 }
920
921
str_format(lua_State * L)922 static int str_format (lua_State *L) {
923 int top = lua_gettop(L);
924 int arg = 1;
925 size_t sfl;
926 const char *strfrmt = luaL_checklstring(L, arg, &sfl);
927 const char *strfrmt_end = strfrmt+sfl;
928 luaL_Buffer b;
929 luaL_buffinit(L, &b);
930 while (strfrmt < strfrmt_end) {
931 if (*strfrmt != L_ESC)
932 luaL_addchar(&b, *strfrmt++);
933 else if (*++strfrmt == L_ESC)
934 luaL_addchar(&b, *strfrmt++); /* %% */
935 else { /* format item */
936 char form[MAX_FORMAT]; /* to store the format (`%...') */
937 char *buff = luaL_prepbuffsize(&b, MAX_ITEM); /* to put formatted item */
938 int nb = 0; /* number of bytes in added item */
939 if (++arg > top)
940 luaL_argerror(L, arg, "no value");
941 strfrmt = scanformat(L, strfrmt, form);
942 switch (*strfrmt++) {
943 case 'c': {
944 nb = str_sprintf(buff, form, luaL_checkint(L, arg));
945 break;
946 }
947 case 'd': case 'i': {
948 lua_Number n = luaL_checknumber(L, arg);
949 LUA_INTFRM_T ni = (LUA_INTFRM_T)n;
950 lua_Number diff = n - (lua_Number)ni;
951 luaL_argcheck(L, -1 < diff && diff < 1, arg,
952 "not a number in proper range");
953 addlenmod(form, LUA_INTFRMLEN);
954 nb = str_sprintf(buff, form, ni);
955 break;
956 }
957 case 'o': case 'u': case 'x': case 'X': {
958 lua_Number n = luaL_checknumber(L, arg);
959 unsigned LUA_INTFRM_T ni = (unsigned LUA_INTFRM_T)n;
960 lua_Number diff = n - (lua_Number)ni;
961 luaL_argcheck(L, -1 < diff && diff < 1, arg,
962 "not a non-negative number in proper range");
963 addlenmod(form, LUA_INTFRMLEN);
964 nb = str_sprintf(buff, form, ni);
965 break;
966 }
967 #if defined(LUA_USE_FLOAT_FORMATS)
968 case 'e': case 'E': case 'f':
969 #if defined(LUA_USE_AFORMAT)
970 case 'a': case 'A':
971 #endif
972 case 'g': case 'G': {
973 addlenmod(form, LUA_FLTFRMLEN);
974 nb = str_sprintf(buff, form, (LUA_FLTFRM_T)luaL_checknumber(L, arg));
975 break;
976 }
977 #endif
978 case 'q': {
979 addquoted(L, &b, arg);
980 break;
981 }
982 case 's': {
983 size_t l;
984 const char *s = luaL_tolstring(L, arg, &l);
985 if (!strchr(form, '.') && l >= 100) {
986 /* no precision and string is too long to be formatted;
987 keep original string */
988 luaL_addvalue(&b);
989 break;
990 }
991 else {
992 nb = str_sprintf(buff, form, s);
993 lua_pop(L, 1); /* remove result from 'luaL_tolstring' */
994 break;
995 }
996 }
997 default: { /* also treat cases `pnLlh' */
998 return luaL_error(L, "invalid option " LUA_QL("%%%c") " to "
999 LUA_QL("format"), *(strfrmt - 1));
1000 }
1001 }
1002 luaL_addsize(&b, nb);
1003 }
1004 }
1005 luaL_pushresult(&b);
1006 return 1;
1007 }
1008
1009 /* }====================================================== */
1010
1011
1012 static const luaL_Reg strlib[] = {
1013 {"byte", str_byte},
1014 {"char", str_char},
1015 {"dump", str_dump},
1016 {"find", str_find},
1017 {"format", str_format},
1018 {"gmatch", str_gmatch},
1019 {"gsub", str_gsub},
1020 {"len", str_len},
1021 {"lower", str_lower},
1022 {"match", str_match},
1023 {"rep", str_rep},
1024 {"reverse", str_reverse},
1025 {"sub", str_sub},
1026 {"upper", str_upper},
1027 {NULL, NULL}
1028 };
1029
1030
createmetatable(lua_State * L)1031 static void createmetatable (lua_State *L) {
1032 lua_createtable(L, 0, 1); /* table to be metatable for strings */
1033 lua_pushliteral(L, ""); /* dummy string */
1034 lua_pushvalue(L, -2); /* copy table */
1035 lua_setmetatable(L, -2); /* set table as metatable for strings */
1036 lua_pop(L, 1); /* pop dummy string */
1037 lua_pushvalue(L, -2); /* get string library */
1038 lua_setfield(L, -2, "__index"); /* metatable.__index = string */
1039 lua_pop(L, 1); /* pop metatable */
1040 }
1041
1042
1043 /*
1044 ** Open string library
1045 */
luaopen_string(lua_State * L)1046 LUAMOD_API int luaopen_string (lua_State *L) {
1047 luaL_newlib(L, strlib);
1048 createmetatable(L);
1049 return 1;
1050 }
1051
1052