Commit | Line | Data |
---|---|---|
a0d0e21e LW |
1 | /* regexec.c |
2 | */ | |
3 | ||
4 | /* | |
5 | * "One Ring to rule them all, One Ring to find them..." | |
6 | */ | |
7 | ||
a687059c LW |
8 | /* NOTE: this is derived from Henry Spencer's regexp code, and should not |
9 | * confused with the original package (see point 3 below). Thanks, Henry! | |
10 | */ | |
11 | ||
12 | /* Additional note: this code is very heavily munged from Henry's version | |
13 | * in places. In some spots I've traded clarity for efficiency, so don't | |
14 | * blame Henry for some of the lack of readability. | |
15 | */ | |
16 | ||
e50aee73 AD |
17 | /* The names of the functions have been changed from regcomp and |
18 | * regexec to pregcomp and pregexec in order to avoid conflicts | |
19 | * with the POSIX routines of the same names. | |
20 | */ | |
21 | ||
f0fcb552 | 22 | /*SUPPRESS 112*/ |
a687059c | 23 | /* |
e50aee73 | 24 | * pregcomp and pregexec -- regsub and regerror are not used in perl |
a687059c LW |
25 | * |
26 | * Copyright (c) 1986 by University of Toronto. | |
27 | * Written by Henry Spencer. Not derived from licensed software. | |
28 | * | |
29 | * Permission is granted to anyone to use this software for any | |
30 | * purpose on any computer system, and to redistribute it freely, | |
31 | * subject to the following restrictions: | |
32 | * | |
33 | * 1. The author is not responsible for the consequences of use of | |
34 | * this software, no matter how awful, even if they arise | |
35 | * from defects in it. | |
36 | * | |
37 | * 2. The origin of this software must not be misrepresented, either | |
38 | * by explicit claim or by omission. | |
39 | * | |
40 | * 3. Altered versions must be plainly marked as such, and must not | |
41 | * be misrepresented as being the original software. | |
42 | * | |
43 | **** Alterations to Henry's code are... | |
44 | **** | |
a0d0e21e | 45 | **** Copyright (c) 1991-1994, Larry Wall |
a687059c | 46 | **** |
9ef589d8 LW |
47 | **** You may distribute under the terms of either the GNU General Public |
48 | **** License or the Artistic License, as specified in the README file. | |
a687059c LW |
49 | * |
50 | * Beware that some of this code is subtly aware of the way operator | |
51 | * precedence is structured in regular expressions. Serious changes in | |
52 | * regular-expression syntax might require a total rethink. | |
53 | */ | |
54 | #include "EXTERN.h" | |
55 | #include "perl.h" | |
56 | #include "regcomp.h" | |
57 | ||
58 | #ifndef STATIC | |
59 | #define STATIC static | |
60 | #endif | |
61 | ||
62 | #ifdef DEBUGGING | |
a0d0e21e LW |
63 | static I32 regnarrate = 0; |
64 | static char* regprogram = 0; | |
a687059c LW |
65 | #endif |
66 | ||
a0d0e21e LW |
67 | /* Current curly descriptor */ |
68 | typedef struct curcur CURCUR; | |
69 | struct curcur { | |
70 | int parenfloor; /* how far back to strip paren data */ | |
71 | int cur; /* how many instances of scan we've matched */ | |
72 | int min; /* the minimal number of scans to match */ | |
73 | int max; /* the maximal number of scans to match */ | |
74 | int minmod; /* whether to work our way up or down */ | |
75 | char * scan; /* the thing to match */ | |
76 | char * next; /* what has to match after it */ | |
77 | char * lastloc; /* where we started matching this scan */ | |
78 | CURCUR * oldcc; /* current curly before we started this one */ | |
79 | }; | |
80 | ||
81 | static CURCUR* regcc; | |
82 | ||
83 | typedef I32 CHECKPOINT; | |
84 | ||
85 | CHECKPOINT regcppush _((I32 parenfloor)); | |
86 | char * regcppop _((void)); | |
87 | ||
88 | CHECKPOINT | |
89 | regcppush(parenfloor) | |
90 | I32 parenfloor; | |
91 | { | |
92 | int retval = savestack_ix; | |
93 | int i = (regsize - parenfloor) * 3; | |
94 | int p; | |
95 | ||
96 | SSCHECK(i + 5); | |
97 | for (p = regsize; p > parenfloor; p--) { | |
98 | SSPUSHPTR(regendp[p]); | |
99 | SSPUSHPTR(regstartp[p]); | |
100 | SSPUSHINT(p); | |
101 | } | |
102 | SSPUSHINT(regsize); | |
103 | SSPUSHINT(*reglastparen); | |
104 | SSPUSHPTR(reginput); | |
105 | SSPUSHINT(i + 3); | |
106 | SSPUSHINT(SAVEt_REGCONTEXT); | |
107 | return retval; | |
108 | } | |
109 | ||
110 | char* | |
111 | regcppop() | |
112 | { | |
113 | I32 i = SSPOPINT; | |
114 | U32 paren = 0; | |
115 | char *input; | |
116 | char *tmps; | |
117 | assert(i == SAVEt_REGCONTEXT); | |
118 | i = SSPOPINT; | |
119 | input = (char *) SSPOPPTR; | |
120 | *reglastparen = SSPOPINT; | |
121 | regsize = SSPOPINT; | |
122 | for (i -= 3; i > 0; i -= 3) { | |
123 | paren = (U32)SSPOPINT; | |
124 | regstartp[paren] = (char *) SSPOPPTR; | |
125 | tmps = (char*)SSPOPPTR; | |
126 | if (paren <= *reglastparen) | |
127 | regendp[paren] = tmps; | |
128 | } | |
129 | for (paren = *reglastparen + 1; paren <= regnpar; paren++) { | |
130 | if (paren > regsize) | |
131 | regstartp[paren] = Nullch; | |
132 | regendp[paren] = Nullch; | |
133 | } | |
134 | return input; | |
135 | } | |
136 | ||
137 | #define regcpblow(cp) leave_scope(cp) | |
138 | ||
a687059c | 139 | /* |
e50aee73 | 140 | * pregexec and friends |
a687059c LW |
141 | */ |
142 | ||
143 | /* | |
a687059c LW |
144 | * Forwards. |
145 | */ | |
a0d0e21e LW |
146 | |
147 | static I32 regmatch _((char *prog)); | |
148 | static I32 regrepeat _((char *p, I32 max)); | |
149 | static I32 regtry _((regexp *prog, char *startpos)); | |
a687059c LW |
150 | |
151 | /* | |
e50aee73 | 152 | - pregexec - match a regexp against a string |
a687059c | 153 | */ |
79072805 | 154 | I32 |
e50aee73 | 155 | pregexec(prog, stringarg, strend, strbeg, minend, screamer, safebase) |
a687059c LW |
156 | register regexp *prog; |
157 | char *stringarg; | |
158 | register char *strend; /* pointer to null at end of string */ | |
159 | char *strbeg; /* real beginning of string */ | |
79072805 LW |
160 | I32 minend; /* end of match must be at least minend after stringarg */ |
161 | SV *screamer; | |
162 | I32 safebase; /* no need to remember string in subbase */ | |
a687059c | 163 | { |
a0d0e21e LW |
164 | register char *s; |
165 | register I32 i; | |
166 | register char *c; | |
167 | register char *startpos = stringarg; | |
168 | register I32 tmp; | |
169 | I32 minlen = 0; /* must match at least this many chars */ | |
170 | I32 dontbother = 0; /* how many characters not to try at end */ | |
171 | CURCUR cc; | |
a687059c | 172 | |
a0d0e21e | 173 | cc.cur = 0; |
4633a7c4 | 174 | cc.oldcc = 0; |
a0d0e21e LW |
175 | regcc = &cc; |
176 | ||
177 | #ifdef DEBUGGING | |
178 | regnarrate = debug & 512; | |
179 | regprogram = prog->program; | |
180 | #endif | |
181 | ||
182 | /* Be paranoid... */ | |
183 | if (prog == NULL || startpos == NULL) { | |
184 | croak("NULL regexp parameter"); | |
185 | return 0; | |
186 | } | |
187 | ||
188 | if (startpos == strbeg) /* is ^ valid at stringarg? */ | |
189 | regprev = '\n'; | |
190 | else { | |
191 | regprev = stringarg[-1]; | |
192 | if (!multiline && regprev == '\n') | |
193 | regprev = '\0'; /* force ^ to NOT match */ | |
194 | } | |
195 | regprecomp = prog->precomp; | |
196 | regnpar = prog->nparens; | |
197 | /* Check validity of program. */ | |
198 | if (UCHARAT(prog->program) != MAGIC) { | |
199 | FAIL("corrupted regexp program"); | |
200 | } | |
201 | ||
202 | if (prog->do_folding) { | |
203 | i = strend - startpos; | |
204 | New(1101,c,i+1,char); | |
205 | Copy(startpos, c, i+1, char); | |
206 | startpos = c; | |
207 | strend = startpos + i; | |
208 | for (s = startpos; s < strend; s++) | |
209 | if (isUPPER(*s)) | |
210 | *s = toLOWER(*s); | |
211 | } | |
212 | ||
213 | /* If there is a "must appear" string, look for it. */ | |
214 | s = startpos; | |
215 | if (prog->regmust != Nullsv && | |
216 | (!(prog->reganch & ROPT_ANCH) | |
217 | || (multiline && prog->regback >= 0)) ) | |
218 | { | |
219 | if (stringarg == strbeg && screamer) { | |
220 | if (screamfirst[BmRARE(prog->regmust)] >= 0) | |
221 | s = screaminstr(screamer,prog->regmust); | |
222 | else | |
223 | s = Nullch; | |
0a12ae7d | 224 | } |
a0d0e21e LW |
225 | else |
226 | s = fbm_instr((unsigned char*)s, (unsigned char*)strend, | |
227 | prog->regmust); | |
228 | if (!s) { | |
229 | ++BmUSEFUL(prog->regmust); /* hooray */ | |
230 | goto phooey; /* not present */ | |
a687059c | 231 | } |
a0d0e21e LW |
232 | else if (prog->regback >= 0) { |
233 | s -= prog->regback; | |
234 | if (s < startpos) | |
235 | s = startpos; | |
236 | minlen = prog->regback + SvCUR(prog->regmust); | |
a687059c | 237 | } |
a0d0e21e LW |
238 | else if (!prog->naughty && --BmUSEFUL(prog->regmust) < 0) { /* boo */ |
239 | SvREFCNT_dec(prog->regmust); | |
240 | prog->regmust = Nullsv; /* disable regmust */ | |
241 | s = startpos; | |
242 | } | |
243 | else { | |
244 | s = startpos; | |
245 | minlen = SvCUR(prog->regmust); | |
a687059c | 246 | } |
a0d0e21e | 247 | } |
a687059c | 248 | |
a0d0e21e LW |
249 | /* Mark beginning of line for ^ . */ |
250 | regbol = startpos; | |
a687059c | 251 | |
a0d0e21e LW |
252 | /* Mark end of line for $ (and such) */ |
253 | regeol = strend; | |
a687059c | 254 | |
a0d0e21e LW |
255 | /* see how far we have to get to not match where we matched before */ |
256 | regtill = startpos+minend; | |
a687059c | 257 | |
a0d0e21e LW |
258 | /* Simplest case: anchored match need be tried only once. */ |
259 | /* [unless multiline is set] */ | |
260 | if (prog->reganch & ROPT_ANCH) { | |
261 | if (regtry(prog, startpos)) | |
262 | goto got_it; | |
263 | else if (multiline || (prog->reganch & ROPT_IMPLICIT)) { | |
264 | if (minlen) | |
265 | dontbother = minlen - 1; | |
266 | strend -= dontbother; | |
267 | /* for multiline we only have to try after newlines */ | |
268 | if (s > startpos) | |
269 | s--; | |
270 | while (s < strend) { | |
271 | if (*s++ == '\n') { | |
272 | if (s < strend && regtry(prog, s)) | |
273 | goto got_it; | |
274 | } | |
35c8bce7 | 275 | } |
35c8bce7 | 276 | } |
a0d0e21e LW |
277 | goto phooey; |
278 | } | |
35c8bce7 | 279 | |
a0d0e21e LW |
280 | /* Messy cases: unanchored match. */ |
281 | if (prog->regstart) { | |
282 | if (prog->reganch & ROPT_SKIP) { /* we have /x+whatever/ */ | |
283 | /* it must be a one character string */ | |
284 | i = SvPVX(prog->regstart)[0]; | |
285 | while (s < strend) { | |
286 | if (*s == i) { | |
287 | if (regtry(prog, s)) | |
a687059c | 288 | goto got_it; |
a0d0e21e LW |
289 | s++; |
290 | while (s < strend && *s == i) | |
291 | s++; | |
a687059c | 292 | } |
a0d0e21e LW |
293 | s++; |
294 | } | |
a687059c | 295 | } |
a0d0e21e LW |
296 | else if (SvPOK(prog->regstart) == 3) { |
297 | /* We know what string it must start with. */ | |
298 | while ((s = fbm_instr((unsigned char*)s, | |
299 | (unsigned char*)strend, prog->regstart)) != NULL) | |
300 | { | |
301 | if (regtry(prog, s)) | |
302 | goto got_it; | |
303 | s++; | |
304 | } | |
305 | } | |
306 | else { | |
307 | c = SvPVX(prog->regstart); | |
308 | while ((s = ninstr(s, strend, c, c + SvCUR(prog->regstart))) != NULL) | |
309 | { | |
310 | if (regtry(prog, s)) | |
311 | goto got_it; | |
312 | s++; | |
313 | } | |
314 | } | |
315 | goto phooey; | |
316 | } | |
317 | /*SUPPRESS 560*/ | |
318 | if (c = prog->regstclass) { | |
319 | I32 doevery = (prog->reganch & ROPT_SKIP) == 0; | |
a687059c | 320 | |
a0d0e21e LW |
321 | if (minlen) |
322 | dontbother = minlen - 1; | |
323 | strend -= dontbother; /* don't bother with what can't match */ | |
324 | tmp = 1; | |
325 | /* We know what class it must start with. */ | |
326 | switch (OP(c)) { | |
327 | case ANYOF: | |
328 | c = OPERAND(c); | |
329 | while (s < strend) { | |
330 | i = UCHARAT(s); | |
331 | if (!(c[i >> 3] & (1 << (i&7)))) { | |
332 | if (tmp && regtry(prog, s)) | |
333 | goto got_it; | |
334 | else | |
335 | tmp = doevery; | |
a687059c | 336 | } |
a0d0e21e LW |
337 | else |
338 | tmp = 1; | |
339 | s++; | |
340 | } | |
341 | break; | |
342 | case BOUND: | |
343 | if (minlen) | |
344 | dontbother++,strend--; | |
345 | if (s != startpos) { | |
346 | i = s[-1]; | |
347 | tmp = isALNUM(i); | |
348 | } | |
349 | else | |
350 | tmp = isALNUM(regprev); /* assume not alphanumeric */ | |
351 | while (s < strend) { | |
352 | i = *s; | |
353 | if (tmp != isALNUM(i)) { | |
354 | tmp = !tmp; | |
355 | if (regtry(prog, s)) | |
356 | goto got_it; | |
a687059c | 357 | } |
a0d0e21e LW |
358 | s++; |
359 | } | |
360 | if ((minlen || tmp) && regtry(prog,s)) | |
361 | goto got_it; | |
362 | break; | |
363 | case NBOUND: | |
364 | if (minlen) | |
365 | dontbother++,strend--; | |
366 | if (s != startpos) { | |
367 | i = s[-1]; | |
368 | tmp = isALNUM(i); | |
369 | } | |
370 | else | |
371 | tmp = isALNUM(regprev); /* assume not alphanumeric */ | |
372 | while (s < strend) { | |
373 | i = *s; | |
374 | if (tmp != isALNUM(i)) | |
375 | tmp = !tmp; | |
376 | else if (regtry(prog, s)) | |
377 | goto got_it; | |
378 | s++; | |
379 | } | |
380 | if ((minlen || !tmp) && regtry(prog,s)) | |
381 | goto got_it; | |
382 | break; | |
383 | case ALNUM: | |
384 | while (s < strend) { | |
385 | i = *s; | |
386 | if (isALNUM(i)) { | |
387 | if (tmp && regtry(prog, s)) | |
388 | goto got_it; | |
a687059c | 389 | else |
a0d0e21e LW |
390 | tmp = doevery; |
391 | } | |
392 | else | |
393 | tmp = 1; | |
394 | s++; | |
395 | } | |
396 | break; | |
397 | case NALNUM: | |
398 | while (s < strend) { | |
399 | i = *s; | |
400 | if (!isALNUM(i)) { | |
401 | if (tmp && regtry(prog, s)) | |
402 | goto got_it; | |
a687059c | 403 | else |
a0d0e21e | 404 | tmp = doevery; |
a687059c | 405 | } |
a0d0e21e LW |
406 | else |
407 | tmp = 1; | |
408 | s++; | |
409 | } | |
410 | break; | |
411 | case SPACE: | |
412 | while (s < strend) { | |
413 | if (isSPACE(*s)) { | |
414 | if (tmp && regtry(prog, s)) | |
415 | goto got_it; | |
416 | else | |
417 | tmp = doevery; | |
2304df62 | 418 | } |
a0d0e21e LW |
419 | else |
420 | tmp = 1; | |
421 | s++; | |
422 | } | |
423 | break; | |
424 | case NSPACE: | |
425 | while (s < strend) { | |
426 | if (!isSPACE(*s)) { | |
427 | if (tmp && regtry(prog, s)) | |
428 | goto got_it; | |
429 | else | |
430 | tmp = doevery; | |
a687059c | 431 | } |
a0d0e21e LW |
432 | else |
433 | tmp = 1; | |
434 | s++; | |
435 | } | |
436 | break; | |
437 | case DIGIT: | |
438 | while (s < strend) { | |
439 | if (isDIGIT(*s)) { | |
440 | if (tmp && regtry(prog, s)) | |
441 | goto got_it; | |
442 | else | |
443 | tmp = doevery; | |
2b69d0c2 | 444 | } |
a0d0e21e LW |
445 | else |
446 | tmp = 1; | |
447 | s++; | |
448 | } | |
449 | break; | |
450 | case NDIGIT: | |
451 | while (s < strend) { | |
452 | if (!isDIGIT(*s)) { | |
453 | if (tmp && regtry(prog, s)) | |
454 | goto got_it; | |
455 | else | |
456 | tmp = doevery; | |
a687059c | 457 | } |
a0d0e21e LW |
458 | else |
459 | tmp = 1; | |
460 | s++; | |
461 | } | |
462 | break; | |
a687059c | 463 | } |
a0d0e21e LW |
464 | } |
465 | else { | |
466 | if (minlen) | |
467 | dontbother = minlen - 1; | |
468 | strend -= dontbother; | |
469 | /* We don't know much -- general case. */ | |
470 | do { | |
471 | if (regtry(prog, s)) | |
472 | goto got_it; | |
473 | } while (s++ < strend); | |
474 | } | |
475 | ||
476 | /* Failure. */ | |
477 | goto phooey; | |
a687059c | 478 | |
a0d0e21e | 479 | got_it: |
420218e7 | 480 | strend += dontbother; /* uncheat */ |
a0d0e21e LW |
481 | prog->subbeg = strbeg; |
482 | prog->subend = strend; | |
483 | if ((!safebase && (prog->nparens || sawampersand)) || prog->do_folding) { | |
a0d0e21e LW |
484 | i = strend - startpos + (stringarg - strbeg); |
485 | if (safebase) { /* no need for $digit later */ | |
486 | s = strbeg; | |
487 | prog->subend = s+i; | |
488 | } | |
489 | else if (strbeg != prog->subbase) { | |
490 | s = savepvn(strbeg,i); /* so $digit will work later */ | |
491 | if (prog->subbase) | |
492 | Safefree(prog->subbase); | |
493 | prog->subbeg = prog->subbase = s; | |
494 | prog->subend = s+i; | |
495 | } | |
496 | else { | |
497 | prog->subbeg = s = prog->subbase; | |
498 | prog->subend = s+i; | |
499 | } | |
500 | s += (stringarg - strbeg); | |
501 | for (i = 0; i <= prog->nparens; i++) { | |
502 | if (prog->endp[i]) { | |
503 | prog->startp[i] = s + (prog->startp[i] - startpos); | |
504 | prog->endp[i] = s + (prog->endp[i] - startpos); | |
505 | } | |
506 | } | |
a687059c | 507 | if (prog->do_folding) |
a0d0e21e LW |
508 | Safefree(startpos); |
509 | } | |
510 | return 1; | |
511 | ||
512 | phooey: | |
513 | if (prog->do_folding) | |
514 | Safefree(startpos); | |
515 | return 0; | |
a687059c LW |
516 | } |
517 | ||
518 | /* | |
519 | - regtry - try match at specific point | |
520 | */ | |
79072805 | 521 | static I32 /* 0 failure, 1 success */ |
a0d0e21e | 522 | regtry(prog, startpos) |
a687059c | 523 | regexp *prog; |
a0d0e21e | 524 | char *startpos; |
a687059c | 525 | { |
a0d0e21e LW |
526 | register I32 i; |
527 | register char **sp; | |
528 | register char **ep; | |
529 | ||
530 | reginput = startpos; | |
531 | regstartp = prog->startp; | |
532 | regendp = prog->endp; | |
533 | reglastparen = &prog->lastparen; | |
534 | prog->lastparen = 0; | |
535 | regsize = 0; | |
536 | ||
537 | sp = prog->startp; | |
538 | ep = prog->endp; | |
539 | if (prog->nparens) { | |
540 | for (i = prog->nparens; i >= 0; i--) { | |
541 | *sp++ = NULL; | |
542 | *ep++ = NULL; | |
a687059c | 543 | } |
a0d0e21e LW |
544 | } |
545 | if (regmatch(prog->program + 1) && reginput >= regtill) { | |
546 | prog->startp[0] = startpos; | |
547 | prog->endp[0] = reginput; | |
548 | return 1; | |
549 | } | |
550 | else | |
551 | return 0; | |
a687059c LW |
552 | } |
553 | ||
554 | /* | |
555 | - regmatch - main matching routine | |
556 | * | |
557 | * Conceptually the strategy is simple: check to see whether the current | |
558 | * node matches, call self recursively to see whether the rest matches, | |
559 | * and then act accordingly. In practice we make some effort to avoid | |
560 | * recursion, in particular by going through "ordinary" nodes (that don't | |
561 | * need to know whether the rest of the match failed) by a loop instead of | |
562 | * by recursion. | |
563 | */ | |
564 | /* [lwall] I've hoisted the register declarations to the outer block in order to | |
565 | * maybe save a little bit of pushing and popping on the stack. It also takes | |
566 | * advantage of machines that use a register save mask on subroutine entry. | |
567 | */ | |
79072805 | 568 | static I32 /* 0 failure, 1 success */ |
a687059c LW |
569 | regmatch(prog) |
570 | char *prog; | |
571 | { | |
a0d0e21e LW |
572 | register char *scan; /* Current node. */ |
573 | char *next; /* Next node. */ | |
574 | register I32 nextchar; | |
575 | register I32 n; /* no or next */ | |
576 | register I32 ln; /* len or last */ | |
577 | register char *s; /* operand or save */ | |
578 | register char *locinput = reginput; | |
579 | int minmod = 0; | |
4633a7c4 LW |
580 | #ifdef DEBUGGING |
581 | static int regindent = 0; | |
582 | regindent++; | |
583 | #endif | |
a0d0e21e LW |
584 | |
585 | nextchar = *locinput; | |
586 | scan = prog; | |
587 | while (scan != NULL) { | |
a687059c | 588 | #ifdef DEBUGGING |
4633a7c4 LW |
589 | #define sayYES goto yes |
590 | #define sayNO goto no | |
591 | #define saySAME(x) if (x) goto yes; else goto no | |
592 | if (regnarrate) { | |
593 | fprintf(stderr, "%*s%2d%-8.8s\t<%.10s>\n", regindent*2, "", | |
a0d0e21e | 594 | scan - regprogram, regprop(scan), locinput); |
4633a7c4 LW |
595 | } |
596 | #else | |
597 | #define sayYES return 1 | |
598 | #define sayNO return 0 | |
599 | #define saySAME(x) return x | |
a687059c LW |
600 | #endif |
601 | ||
602 | #ifdef REGALIGN | |
a0d0e21e LW |
603 | next = scan + NEXT(scan); |
604 | if (next == scan) | |
605 | next = NULL; | |
a687059c | 606 | #else |
a0d0e21e | 607 | next = regnext(scan); |
a687059c LW |
608 | #endif |
609 | ||
a0d0e21e LW |
610 | switch (OP(scan)) { |
611 | case BOL: | |
612 | if (locinput == regbol | |
613 | ? regprev == '\n' | |
614 | : ((nextchar || locinput < regeol) && locinput[-1] == '\n') ) | |
615 | { | |
616 | /* regtill = regbol; */ | |
617 | break; | |
618 | } | |
4633a7c4 | 619 | sayNO; |
a0d0e21e LW |
620 | case MBOL: |
621 | if (locinput == regbol | |
622 | ? regprev == '\n' | |
623 | : ((nextchar || locinput < regeol) && locinput[-1] == '\n') ) | |
624 | { | |
625 | break; | |
626 | } | |
4633a7c4 | 627 | sayNO; |
a0d0e21e LW |
628 | case SBOL: |
629 | if (locinput == regbol && regprev == '\n') | |
630 | break; | |
4633a7c4 | 631 | sayNO; |
a0d0e21e LW |
632 | case GBOL: |
633 | if (locinput == regbol) | |
634 | break; | |
4633a7c4 | 635 | sayNO; |
a0d0e21e LW |
636 | case EOL: |
637 | if (multiline) | |
638 | goto meol; | |
639 | else | |
640 | goto seol; | |
641 | case MEOL: | |
642 | meol: | |
643 | if ((nextchar || locinput < regeol) && nextchar != '\n') | |
4633a7c4 | 644 | sayNO; |
a0d0e21e LW |
645 | break; |
646 | case SEOL: | |
647 | seol: | |
648 | if ((nextchar || locinput < regeol) && nextchar != '\n') | |
4633a7c4 | 649 | sayNO; |
a0d0e21e | 650 | if (regeol - locinput > 1) |
4633a7c4 | 651 | sayNO; |
a0d0e21e LW |
652 | break; |
653 | case SANY: | |
654 | if (!nextchar && locinput >= regeol) | |
4633a7c4 | 655 | sayNO; |
a0d0e21e LW |
656 | nextchar = *++locinput; |
657 | break; | |
658 | case ANY: | |
659 | if (!nextchar && locinput >= regeol || nextchar == '\n') | |
4633a7c4 | 660 | sayNO; |
a0d0e21e LW |
661 | nextchar = *++locinput; |
662 | break; | |
663 | case EXACTLY: | |
664 | s = OPERAND(scan); | |
665 | ln = *s++; | |
666 | /* Inline the first character, for speed. */ | |
667 | if (*s != nextchar) | |
4633a7c4 | 668 | sayNO; |
a0d0e21e | 669 | if (regeol - locinput < ln) |
4633a7c4 | 670 | sayNO; |
a0d0e21e | 671 | if (ln > 1 && bcmp(s, locinput, ln) != 0) |
4633a7c4 | 672 | sayNO; |
a0d0e21e LW |
673 | locinput += ln; |
674 | nextchar = *locinput; | |
675 | break; | |
676 | case ANYOF: | |
677 | s = OPERAND(scan); | |
678 | if (nextchar < 0) | |
679 | nextchar = UCHARAT(locinput); | |
680 | if (s[nextchar >> 3] & (1 << (nextchar&7))) | |
4633a7c4 | 681 | sayNO; |
a0d0e21e | 682 | if (!nextchar && locinput >= regeol) |
4633a7c4 | 683 | sayNO; |
a0d0e21e LW |
684 | nextchar = *++locinput; |
685 | break; | |
686 | case ALNUM: | |
687 | if (!nextchar) | |
4633a7c4 | 688 | sayNO; |
a0d0e21e | 689 | if (!isALNUM(nextchar)) |
4633a7c4 | 690 | sayNO; |
a0d0e21e LW |
691 | nextchar = *++locinput; |
692 | break; | |
693 | case NALNUM: | |
694 | if (!nextchar && locinput >= regeol) | |
4633a7c4 | 695 | sayNO; |
a0d0e21e | 696 | if (isALNUM(nextchar)) |
4633a7c4 | 697 | sayNO; |
a0d0e21e LW |
698 | nextchar = *++locinput; |
699 | break; | |
700 | case NBOUND: | |
701 | case BOUND: | |
702 | if (locinput == regbol) /* was last char in word? */ | |
703 | ln = isALNUM(regprev); | |
704 | else | |
705 | ln = isALNUM(locinput[-1]); | |
706 | n = isALNUM(nextchar); /* is next char in word? */ | |
707 | if ((ln == n) == (OP(scan) == BOUND)) | |
4633a7c4 | 708 | sayNO; |
a0d0e21e LW |
709 | break; |
710 | case SPACE: | |
711 | if (!nextchar && locinput >= regeol) | |
4633a7c4 | 712 | sayNO; |
a0d0e21e | 713 | if (!isSPACE(nextchar)) |
4633a7c4 | 714 | sayNO; |
a0d0e21e LW |
715 | nextchar = *++locinput; |
716 | break; | |
717 | case NSPACE: | |
718 | if (!nextchar) | |
4633a7c4 | 719 | sayNO; |
a0d0e21e | 720 | if (isSPACE(nextchar)) |
4633a7c4 | 721 | sayNO; |
a0d0e21e LW |
722 | nextchar = *++locinput; |
723 | break; | |
724 | case DIGIT: | |
725 | if (!isDIGIT(nextchar)) | |
4633a7c4 | 726 | sayNO; |
a0d0e21e LW |
727 | nextchar = *++locinput; |
728 | break; | |
729 | case NDIGIT: | |
730 | if (!nextchar && locinput >= regeol) | |
4633a7c4 | 731 | sayNO; |
a0d0e21e | 732 | if (isDIGIT(nextchar)) |
4633a7c4 | 733 | sayNO; |
a0d0e21e LW |
734 | nextchar = *++locinput; |
735 | break; | |
736 | case REF: | |
737 | n = ARG1(scan); /* which paren pair */ | |
738 | s = regstartp[n]; | |
739 | if (!s) | |
4633a7c4 | 740 | sayNO; |
a0d0e21e | 741 | if (!regendp[n]) |
4633a7c4 | 742 | sayNO; |
a0d0e21e LW |
743 | if (s == regendp[n]) |
744 | break; | |
745 | /* Inline the first character, for speed. */ | |
746 | if (*s != nextchar) | |
4633a7c4 | 747 | sayNO; |
a0d0e21e LW |
748 | ln = regendp[n] - s; |
749 | if (locinput + ln > regeol) | |
4633a7c4 | 750 | sayNO; |
a0d0e21e | 751 | if (ln > 1 && bcmp(s, locinput, ln) != 0) |
4633a7c4 | 752 | sayNO; |
a0d0e21e LW |
753 | locinput += ln; |
754 | nextchar = *locinput; | |
755 | break; | |
756 | ||
757 | case NOTHING: | |
758 | break; | |
759 | case BACK: | |
760 | break; | |
761 | case OPEN: | |
762 | n = ARG1(scan); /* which paren pair */ | |
763 | regstartp[n] = locinput; | |
764 | if (n > regsize) | |
765 | regsize = n; | |
766 | break; | |
767 | case CLOSE: | |
768 | n = ARG1(scan); /* which paren pair */ | |
769 | regendp[n] = locinput; | |
770 | if (n > *reglastparen) | |
771 | *reglastparen = n; | |
772 | break; | |
773 | case CURLYX: { | |
774 | CURCUR cc; | |
775 | CHECKPOINT cp = savestack_ix; | |
776 | cc.oldcc = regcc; | |
777 | regcc = &cc; | |
778 | cc.parenfloor = *reglastparen; | |
779 | cc.cur = -1; | |
780 | cc.min = ARG1(scan); | |
781 | cc.max = ARG2(scan); | |
782 | cc.scan = NEXTOPER(scan) + 4; | |
783 | cc.next = next; | |
784 | cc.minmod = minmod; | |
785 | cc.lastloc = 0; | |
786 | reginput = locinput; | |
787 | n = regmatch(PREVOPER(next)); /* start on the WHILEM */ | |
788 | regcpblow(cp); | |
789 | regcc = cc.oldcc; | |
4633a7c4 | 790 | saySAME(n); |
a0d0e21e LW |
791 | } |
792 | /* NOT REACHED */ | |
793 | case WHILEM: { | |
794 | /* | |
795 | * This is really hard to understand, because after we match | |
796 | * what we're trying to match, we must make sure the rest of | |
797 | * the RE is going to match for sure, and to do that we have | |
798 | * to go back UP the parse tree by recursing ever deeper. And | |
799 | * if it fails, we have to reset our parent's current state | |
800 | * that we can try again after backing off. | |
801 | */ | |
802 | ||
803 | CURCUR* cc = regcc; | |
4633a7c4 | 804 | n = cc->cur + 1; /* how many we know we matched */ |
a0d0e21e LW |
805 | reginput = locinput; |
806 | ||
4633a7c4 LW |
807 | #ifdef DEBUGGING |
808 | if (regnarrate) | |
809 | fprintf(stderr, "%*s %d %lx\n", regindent*2, "", | |
810 | n, (long)cc); | |
811 | #endif | |
812 | ||
a0d0e21e LW |
813 | /* If degenerate scan matches "", assume scan done. */ |
814 | ||
815 | if (locinput == cc->lastloc) { | |
816 | regcc = cc->oldcc; | |
817 | ln = regcc->cur; | |
818 | if (regmatch(cc->next)) | |
4633a7c4 | 819 | sayYES; |
a0d0e21e LW |
820 | regcc->cur = ln; |
821 | regcc = cc; | |
4633a7c4 | 822 | sayNO; |
a0d0e21e LW |
823 | } |
824 | ||
825 | /* First just match a string of min scans. */ | |
826 | ||
827 | if (n < cc->min) { | |
828 | cc->cur = n; | |
829 | cc->lastloc = locinput; | |
4633a7c4 LW |
830 | if (regmatch(cc->scan)) |
831 | sayYES; | |
832 | cc->cur = n - 1; | |
833 | sayNO; | |
a0d0e21e LW |
834 | } |
835 | ||
836 | /* Prefer next over scan for minimal matching. */ | |
837 | ||
838 | if (cc->minmod) { | |
839 | regcc = cc->oldcc; | |
840 | ln = regcc->cur; | |
841 | if (regmatch(cc->next)) | |
4633a7c4 | 842 | sayYES; /* All done. */ |
a0d0e21e LW |
843 | regcc->cur = ln; |
844 | regcc = cc; | |
845 | ||
846 | if (n >= cc->max) /* Maximum greed exceeded? */ | |
4633a7c4 | 847 | sayNO; |
a687059c | 848 | |
a0d0e21e LW |
849 | /* Try scanning more and see if it helps. */ |
850 | reginput = locinput; | |
851 | cc->cur = n; | |
852 | cc->lastloc = locinput; | |
4633a7c4 LW |
853 | if (regmatch(cc->scan)) |
854 | sayYES; | |
855 | cc->cur = n - 1; | |
856 | sayNO; | |
a0d0e21e LW |
857 | } |
858 | ||
859 | /* Prefer scan over next for maximal matching. */ | |
860 | ||
861 | if (n < cc->max) { /* More greed allowed? */ | |
862 | regcppush(cc->parenfloor); | |
863 | cc->cur = n; | |
864 | cc->lastloc = locinput; | |
865 | if (regmatch(cc->scan)) | |
4633a7c4 | 866 | sayYES; |
a0d0e21e LW |
867 | regcppop(); /* Restore some previous $<digit>s? */ |
868 | reginput = locinput; | |
869 | } | |
870 | ||
871 | /* Failed deeper matches of scan, so see if this one works. */ | |
872 | regcc = cc->oldcc; | |
873 | ln = regcc->cur; | |
874 | if (regmatch(cc->next)) | |
4633a7c4 | 875 | sayYES; |
a0d0e21e LW |
876 | regcc->cur = ln; |
877 | regcc = cc; | |
4633a7c4 LW |
878 | cc->cur = n - 1; |
879 | sayNO; | |
a0d0e21e LW |
880 | } |
881 | /* NOT REACHED */ | |
882 | case BRANCH: { | |
883 | if (OP(next) != BRANCH) /* No choice. */ | |
884 | next = NEXTOPER(scan);/* Avoid recursion. */ | |
885 | else { | |
748a9306 | 886 | int lastparen = *reglastparen; |
a0d0e21e LW |
887 | do { |
888 | reginput = locinput; | |
889 | if (regmatch(NEXTOPER(scan))) | |
4633a7c4 | 890 | sayYES; |
748a9306 LW |
891 | for (n = *reglastparen; n > lastparen; n--) |
892 | regendp[n] = 0; | |
893 | *reglastparen = n; | |
894 | ||
a687059c | 895 | #ifdef REGALIGN |
a0d0e21e LW |
896 | /*SUPPRESS 560*/ |
897 | if (n = NEXT(scan)) | |
898 | scan += n; | |
899 | else | |
900 | scan = NULL; | |
a687059c | 901 | #else |
a0d0e21e | 902 | scan = regnext(scan); |
79072805 | 903 | #endif |
a0d0e21e | 904 | } while (scan != NULL && OP(scan) == BRANCH); |
4633a7c4 | 905 | sayNO; |
a0d0e21e | 906 | /* NOTREACHED */ |
a687059c | 907 | } |
a0d0e21e LW |
908 | } |
909 | break; | |
910 | case MINMOD: | |
911 | minmod = 1; | |
912 | break; | |
913 | case CURLY: | |
914 | ln = ARG1(scan); /* min to match */ | |
915 | n = ARG2(scan); /* max to match */ | |
916 | scan = NEXTOPER(scan) + 4; | |
917 | goto repeat; | |
918 | case STAR: | |
919 | ln = 0; | |
920 | n = 32767; | |
921 | scan = NEXTOPER(scan); | |
922 | goto repeat; | |
923 | case PLUS: | |
924 | /* | |
925 | * Lookahead to avoid useless match attempts | |
926 | * when we know what character comes next. | |
927 | */ | |
928 | ln = 1; | |
929 | n = 32767; | |
930 | scan = NEXTOPER(scan); | |
931 | repeat: | |
932 | if (OP(next) == EXACTLY) | |
933 | nextchar = *(OPERAND(next)+1); | |
934 | else | |
935 | nextchar = -1000; | |
936 | reginput = locinput; | |
937 | if (minmod) { | |
938 | minmod = 0; | |
939 | if (ln && regrepeat(scan, ln) < ln) | |
4633a7c4 | 940 | sayNO; |
8e07c86e | 941 | while (n >= ln || (n == 32767 && ln > 0)) { /* ln overflow ? */ |
a0d0e21e LW |
942 | /* If it could work, try it. */ |
943 | if (nextchar == -1000 || *reginput == nextchar) | |
944 | if (regmatch(next)) | |
4633a7c4 | 945 | sayYES; |
a0d0e21e | 946 | /* Couldn't or didn't -- back up. */ |
748a9306 | 947 | reginput = locinput + ln; |
a0d0e21e LW |
948 | if (regrepeat(scan, 1)) { |
949 | ln++; | |
950 | reginput = locinput + ln; | |
951 | } | |
952 | else | |
4633a7c4 | 953 | sayNO; |
a0d0e21e LW |
954 | } |
955 | } | |
956 | else { | |
957 | n = regrepeat(scan, n); | |
958 | if (ln < n && regkind[(U8)OP(next)] == EOL && | |
959 | (!multiline || OP(next) == SEOL)) | |
960 | ln = n; /* why back off? */ | |
961 | while (n >= ln) { | |
962 | /* If it could work, try it. */ | |
963 | if (nextchar == -1000 || *reginput == nextchar) | |
964 | if (regmatch(next)) | |
4633a7c4 | 965 | sayYES; |
a0d0e21e LW |
966 | /* Couldn't or didn't -- back up. */ |
967 | n--; | |
968 | reginput = locinput + n; | |
969 | } | |
970 | } | |
4633a7c4 | 971 | sayNO; |
a0d0e21e LW |
972 | case SUCCEED: |
973 | case END: | |
974 | reginput = locinput; /* put where regtry can find it */ | |
4633a7c4 | 975 | sayYES; /* Success! */ |
a0d0e21e LW |
976 | case IFMATCH: |
977 | reginput = locinput; | |
978 | scan = NEXTOPER(scan); | |
979 | if (!regmatch(scan)) | |
4633a7c4 | 980 | sayNO; |
a0d0e21e LW |
981 | break; |
982 | case UNLESSM: | |
983 | reginput = locinput; | |
984 | scan = NEXTOPER(scan); | |
985 | if (regmatch(scan)) | |
4633a7c4 | 986 | sayNO; |
a0d0e21e LW |
987 | break; |
988 | default: | |
989 | fprintf(stderr, "%x %d\n",(unsigned)scan,scan[1]); | |
990 | FAIL("regexp memory corruption"); | |
a687059c | 991 | } |
a0d0e21e LW |
992 | scan = next; |
993 | } | |
a687059c | 994 | |
a0d0e21e LW |
995 | /* |
996 | * We get here only if there's trouble -- normally "case END" is | |
997 | * the terminating point. | |
998 | */ | |
999 | FAIL("corrupted regexp pointers"); | |
1000 | /*NOTREACHED*/ | |
4633a7c4 LW |
1001 | sayNO; |
1002 | ||
1003 | yes: | |
1004 | #ifdef DEBUGGING | |
1005 | regindent--; | |
1006 | #endif | |
1007 | return 1; | |
1008 | ||
1009 | no: | |
1010 | #ifdef DEBUGGING | |
1011 | regindent--; | |
1012 | #endif | |
a0d0e21e | 1013 | return 0; |
a687059c LW |
1014 | } |
1015 | ||
1016 | /* | |
1017 | - regrepeat - repeatedly match something simple, report how many | |
1018 | */ | |
1019 | /* | |
1020 | * [This routine now assumes that it will only match on things of length 1. | |
1021 | * That was true before, but now we assume scan - reginput is the count, | |
1022 | * rather than incrementing count on every character.] | |
1023 | */ | |
79072805 | 1024 | static I32 |
00bf170e | 1025 | regrepeat(p, max) |
a687059c | 1026 | char *p; |
79072805 | 1027 | I32 max; |
a687059c | 1028 | { |
a0d0e21e LW |
1029 | register char *scan; |
1030 | register char *opnd; | |
1031 | register I32 c; | |
1032 | register char *loceol = regeol; | |
1033 | ||
1034 | scan = reginput; | |
1035 | if (max != 32767 && max < loceol - scan) | |
1036 | loceol = scan + max; | |
1037 | opnd = OPERAND(p); | |
1038 | switch (OP(p)) { | |
1039 | case ANY: | |
1040 | while (scan < loceol && *scan != '\n') | |
1041 | scan++; | |
1042 | break; | |
1043 | case SANY: | |
1044 | scan = loceol; | |
1045 | break; | |
1046 | case EXACTLY: /* length of string is 1 */ | |
1047 | opnd++; | |
1048 | while (scan < loceol && *opnd == *scan) | |
1049 | scan++; | |
1050 | break; | |
1051 | case ANYOF: | |
1052 | c = UCHARAT(scan); | |
1053 | while (scan < loceol && !(opnd[c >> 3] & (1 << (c & 7)))) { | |
1054 | scan++; | |
1055 | c = UCHARAT(scan); | |
a687059c | 1056 | } |
a0d0e21e LW |
1057 | break; |
1058 | case ALNUM: | |
1059 | while (scan < loceol && isALNUM(*scan)) | |
1060 | scan++; | |
1061 | break; | |
1062 | case NALNUM: | |
1063 | while (scan < loceol && !isALNUM(*scan)) | |
1064 | scan++; | |
1065 | break; | |
1066 | case SPACE: | |
1067 | while (scan < loceol && isSPACE(*scan)) | |
1068 | scan++; | |
1069 | break; | |
1070 | case NSPACE: | |
1071 | while (scan < loceol && !isSPACE(*scan)) | |
1072 | scan++; | |
1073 | break; | |
1074 | case DIGIT: | |
1075 | while (scan < loceol && isDIGIT(*scan)) | |
1076 | scan++; | |
1077 | break; | |
1078 | case NDIGIT: | |
1079 | while (scan < loceol && !isDIGIT(*scan)) | |
1080 | scan++; | |
1081 | break; | |
1082 | default: /* Called on something of 0 width. */ | |
1083 | break; /* So match right here or not at all. */ | |
1084 | } | |
a687059c | 1085 | |
a0d0e21e LW |
1086 | c = scan - reginput; |
1087 | reginput = scan; | |
a687059c | 1088 | |
a0d0e21e | 1089 | return(c); |
a687059c LW |
1090 | } |
1091 | ||
1092 | /* | |
1093 | - regnext - dig the "next" pointer out of a node | |
1094 | * | |
1095 | * [Note, when REGALIGN is defined there are two places in regmatch() | |
1096 | * that bypass this code for speed.] | |
1097 | */ | |
1098 | char * | |
1099 | regnext(p) | |
1100 | register char *p; | |
1101 | { | |
a0d0e21e | 1102 | register I32 offset; |
a687059c | 1103 | |
a0d0e21e LW |
1104 | if (p == ®dummy) |
1105 | return(NULL); | |
a687059c | 1106 | |
a0d0e21e LW |
1107 | offset = NEXT(p); |
1108 | if (offset == 0) | |
1109 | return(NULL); | |
a687059c LW |
1110 | |
1111 | #ifdef REGALIGN | |
a0d0e21e | 1112 | return(p+offset); |
a687059c | 1113 | #else |
a0d0e21e LW |
1114 | if (OP(p) == BACK) |
1115 | return(p-offset); | |
1116 | else | |
1117 | return(p+offset); | |
a687059c LW |
1118 | #endif |
1119 | } |