Commit | Line | Data |
a687059c |
1 | /* NOTE: this is derived from Henry Spencer's regexp code, and should not |
2 | * confused with the original package (see point 3 below). Thanks, Henry! |
3 | */ |
4 | |
5 | /* Additional note: this code is very heavily munged from Henry's version |
6 | * in places. In some spots I've traded clarity for efficiency, so don't |
7 | * blame Henry for some of the lack of readability. |
8 | */ |
9 | |
0a12ae7d |
10 | /* $Header: regexec.c,v 3.0.1.5 90/10/16 10:25:36 lwall Locked $ |
a687059c |
11 | * |
12 | * $Log: regexec.c,v $ |
0a12ae7d |
13 | * Revision 3.0.1.5 90/10/16 10:25:36 lwall |
14 | * patch29: /^pat/ occasionally matched in middle of string when $* = 0 |
15 | * patch29: /.{n,m}$/ could match with fewer than n characters remaining |
16 | * patch29: /\d{9}/ could match more than 9 characters |
17 | * |
00bf170e |
18 | * Revision 3.0.1.4 90/08/09 05:12:03 lwall |
19 | * patch19: sped up /x+y/ patterns greatly by not retrying on every x |
20 | * patch19: inhibited backoff on patterns anchored to the end like /\s+$/ |
21 | * patch19: sped up {m,n} on simple items |
22 | * patch19: $' broke on embedded nulls |
23 | * patch19: $ will now only match at end of string if $* == 0 |
24 | * |
ac58e20f |
25 | * Revision 3.0.1.3 90/02/28 18:14:39 lwall |
26 | * patch9: /[\200-\377]/ didn't work on machines with signed chars |
27 | * patch9: \d, \w, and \s could misfire on characters with high bit set |
28 | * patch9: /\bfoo/i didn't work |
29 | * |
663a0e37 |
30 | * Revision 3.0.1.2 89/12/21 20:16:27 lwall |
31 | * patch7: certain patterns didn't match correctly at end of string |
32 | * |
ae986130 |
33 | * Revision 3.0.1.1 89/11/11 04:52:04 lwall |
34 | * patch2: /\b$foo/ didn't work |
35 | * |
a687059c |
36 | * Revision 3.0 89/10/18 15:22:53 lwall |
37 | * 3.0 baseline |
38 | * |
39 | */ |
40 | |
41 | /* |
42 | * regcomp and regexec -- regsub and regerror are not used in perl |
43 | * |
44 | * Copyright (c) 1986 by University of Toronto. |
45 | * Written by Henry Spencer. Not derived from licensed software. |
46 | * |
47 | * Permission is granted to anyone to use this software for any |
48 | * purpose on any computer system, and to redistribute it freely, |
49 | * subject to the following restrictions: |
50 | * |
51 | * 1. The author is not responsible for the consequences of use of |
52 | * this software, no matter how awful, even if they arise |
53 | * from defects in it. |
54 | * |
55 | * 2. The origin of this software must not be misrepresented, either |
56 | * by explicit claim or by omission. |
57 | * |
58 | * 3. Altered versions must be plainly marked as such, and must not |
59 | * be misrepresented as being the original software. |
60 | * |
61 | **** Alterations to Henry's code are... |
62 | **** |
63 | **** Copyright (c) 1989, Larry Wall |
64 | **** |
65 | **** You may distribute under the terms of the GNU General Public License |
66 | **** as specified in the README file that comes with the perl 3.0 kit. |
67 | * |
68 | * Beware that some of this code is subtly aware of the way operator |
69 | * precedence is structured in regular expressions. Serious changes in |
70 | * regular-expression syntax might require a total rethink. |
71 | */ |
72 | #include "EXTERN.h" |
73 | #include "perl.h" |
74 | #include "regcomp.h" |
75 | |
76 | #ifndef STATIC |
77 | #define STATIC static |
78 | #endif |
79 | |
80 | #ifdef DEBUGGING |
81 | int regnarrate = 0; |
82 | #endif |
83 | |
ac58e20f |
84 | #define isALNUM(c) (isascii(c) && (isalpha(c) || isdigit(c) || c == '_')) |
85 | #define isSPACE(c) (isascii(c) && isspace(c)) |
86 | #define isDIGIT(c) (isascii(c) && isdigit(c)) |
87 | #define isUPPER(c) (isascii(c) && isupper(c)) |
88 | |
a687059c |
89 | /* |
90 | * regexec and friends |
91 | */ |
92 | |
93 | /* |
94 | * Global work variables for regexec(). |
95 | */ |
96 | static char *regprecomp; |
97 | static char *reginput; /* String-input pointer. */ |
ac58e20f |
98 | static char regprev; /* char before regbol, \n if none */ |
a687059c |
99 | static char *regbol; /* Beginning of input, for ^ check. */ |
100 | static char *regeol; /* End of input, for $ check. */ |
101 | static char **regstartp; /* Pointer to startp array. */ |
102 | static char **regendp; /* Ditto for endp. */ |
103 | static char *reglastparen; /* Similarly for lastparen. */ |
104 | static char *regtill; |
105 | |
106 | static char *regmystartp[10]; /* For remembering backreferences. */ |
107 | static char *regmyendp[10]; |
108 | |
109 | /* |
110 | * Forwards. |
111 | */ |
112 | STATIC int regtry(); |
113 | STATIC int regmatch(); |
114 | STATIC int regrepeat(); |
115 | |
116 | extern int multiline; |
117 | |
118 | /* |
119 | - regexec - match a regexp against a string |
120 | */ |
121 | int |
122 | regexec(prog, stringarg, strend, strbeg, minend, screamer, safebase) |
123 | register regexp *prog; |
124 | char *stringarg; |
125 | register char *strend; /* pointer to null at end of string */ |
126 | char *strbeg; /* real beginning of string */ |
127 | int minend; /* end of match must be at least minend after stringarg */ |
128 | STR *screamer; |
129 | int safebase; /* no need to remember string in subbase */ |
130 | { |
131 | register char *s; |
132 | register int i; |
133 | register char *c; |
134 | register char *string = stringarg; |
135 | register int tmp; |
136 | int minlen = 0; /* must match at least this many chars */ |
137 | int dontbother = 0; /* how many characters not to try at end */ |
a687059c |
138 | |
139 | /* Be paranoid... */ |
140 | if (prog == NULL || string == NULL) { |
141 | fatal("NULL regexp parameter"); |
142 | return(0); |
143 | } |
144 | |
ac58e20f |
145 | if (string == strbeg) /* is ^ valid at stringarg? */ |
146 | regprev = '\n'; |
0a12ae7d |
147 | else { |
ac58e20f |
148 | regprev = stringarg[-1]; |
0a12ae7d |
149 | if (!multiline && regprev == '\n') |
150 | regprev = '\0'; /* force ^ to NOT match */ |
151 | } |
a687059c |
152 | regprecomp = prog->precomp; |
153 | /* Check validity of program. */ |
154 | if (UCHARAT(prog->program) != MAGIC) { |
155 | FAIL("corrupted regexp program"); |
156 | } |
157 | |
158 | if (prog->do_folding) { |
159 | safebase = FALSE; |
160 | i = strend - string; |
161 | New(1101,c,i+1,char); |
162 | (void)bcopy(string, c, i+1); |
163 | string = c; |
164 | strend = string + i; |
165 | for (s = string; s < strend; s++) |
ac58e20f |
166 | if (isUPPER(*s)) |
a687059c |
167 | *s = tolower(*s); |
168 | } |
169 | |
170 | /* If there is a "must appear" string, look for it. */ |
171 | s = string; |
172 | if (prog->regmust != Nullstr) { |
ac58e20f |
173 | if (stringarg == strbeg && screamer) { |
a687059c |
174 | if (screamfirst[prog->regmust->str_rare] >= 0) |
175 | s = screaminstr(screamer,prog->regmust); |
176 | else |
177 | s = Nullch; |
178 | } |
179 | #ifndef lint |
180 | else |
181 | s = fbminstr((unsigned char*)s, (unsigned char*)strend, |
182 | prog->regmust); |
183 | #endif |
184 | if (!s) { |
185 | ++prog->regmust->str_u.str_useful; /* hooray */ |
186 | goto phooey; /* not present */ |
187 | } |
188 | else if (prog->regback >= 0) { |
189 | s -= prog->regback; |
190 | if (s < string) |
191 | s = string; |
192 | minlen = prog->regback + prog->regmust->str_cur; |
193 | } |
194 | else if (--prog->regmust->str_u.str_useful < 0) { /* boo */ |
195 | str_free(prog->regmust); |
196 | prog->regmust = Nullstr; /* disable regmust */ |
197 | s = string; |
198 | } |
199 | else { |
200 | s = string; |
201 | minlen = prog->regmust->str_cur; |
202 | } |
203 | } |
204 | |
205 | /* Mark beginning of line for ^ . */ |
ac58e20f |
206 | regbol = string; |
a687059c |
207 | |
208 | /* Mark end of line for $ (and such) */ |
209 | regeol = strend; |
210 | |
211 | /* see how far we have to get to not match where we matched before */ |
212 | regtill = string+minend; |
213 | |
214 | /* Simplest case: anchored match need be tried only once. */ |
215 | /* [unless multiline is set] */ |
00bf170e |
216 | if (prog->reganch & 1) { |
a687059c |
217 | if (regtry(prog, string)) |
218 | goto got_it; |
219 | else if (multiline) { |
220 | if (minlen) |
221 | dontbother = minlen - 1; |
222 | strend -= dontbother; |
223 | /* for multiline we only have to try after newlines */ |
224 | if (s > string) |
225 | s--; |
00bf170e |
226 | while (s < strend) { |
227 | if (*s++ == '\n') { |
228 | if (s < strend && regtry(prog, s)) |
a687059c |
229 | goto got_it; |
230 | } |
231 | } |
232 | } |
233 | goto phooey; |
234 | } |
235 | |
236 | /* Messy cases: unanchored match. */ |
237 | if (prog->regstart) { |
00bf170e |
238 | if (prog->reganch & 2) { /* we have /x+whatever/ */ |
239 | /* it must be a one character string */ |
240 | i = prog->regstart->str_ptr[0]; |
241 | while (s < strend) { |
242 | if (*s == i) { |
243 | if (regtry(prog, s)) |
244 | goto got_it; |
245 | s++; |
246 | while (s < strend && *s == i) |
247 | s++; |
248 | } |
249 | s++; |
250 | } |
251 | } |
252 | else if (prog->regstart->str_pok == 3) { |
253 | /* We know what string it must start with. */ |
a687059c |
254 | #ifndef lint |
255 | while ((s = fbminstr((unsigned char*)s, |
256 | (unsigned char*)strend, prog->regstart)) != NULL) |
257 | #else |
258 | while (s = Nullch) |
259 | #endif |
260 | { |
261 | if (regtry(prog, s)) |
262 | goto got_it; |
263 | s++; |
264 | } |
265 | } |
266 | else { |
267 | c = prog->regstart->str_ptr; |
268 | while ((s = ninstr(s, strend, |
269 | c, c + prog->regstart->str_cur )) != NULL) { |
270 | if (regtry(prog, s)) |
271 | goto got_it; |
272 | s++; |
273 | } |
274 | } |
275 | goto phooey; |
276 | } |
277 | if (c = prog->regstclass) { |
00bf170e |
278 | int doevery = (prog->reganch & 2) == 0; |
279 | |
a687059c |
280 | if (minlen) |
281 | dontbother = minlen - 1; |
282 | strend -= dontbother; /* don't bother with what can't match */ |
00bf170e |
283 | tmp = 1; |
a687059c |
284 | /* We know what class it must start with. */ |
285 | switch (OP(c)) { |
00bf170e |
286 | case ANYOF: |
a687059c |
287 | c = OPERAND(c); |
288 | while (s < strend) { |
ac58e20f |
289 | i = UCHARAT(s); |
00bf170e |
290 | if (!(c[i >> 3] & (1 << (i&7)))) { |
291 | if (tmp && regtry(prog, s)) |
a687059c |
292 | goto got_it; |
00bf170e |
293 | else |
294 | tmp = doevery; |
295 | } |
296 | else |
297 | tmp = 1; |
a687059c |
298 | s++; |
299 | } |
300 | break; |
301 | case BOUND: |
302 | if (minlen) |
303 | dontbother++,strend--; |
304 | if (s != string) { |
305 | i = s[-1]; |
ac58e20f |
306 | tmp = isALNUM(i); |
a687059c |
307 | } |
308 | else |
ac58e20f |
309 | tmp = isALNUM(regprev); /* assume not alphanumeric */ |
a687059c |
310 | while (s < strend) { |
311 | i = *s; |
ac58e20f |
312 | if (tmp != isALNUM(i)) { |
a687059c |
313 | tmp = !tmp; |
314 | if (regtry(prog, s)) |
315 | goto got_it; |
316 | } |
317 | s++; |
318 | } |
ae986130 |
319 | if ((minlen || tmp) && regtry(prog,s)) |
a687059c |
320 | goto got_it; |
321 | break; |
322 | case NBOUND: |
323 | if (minlen) |
324 | dontbother++,strend--; |
325 | if (s != string) { |
326 | i = s[-1]; |
ac58e20f |
327 | tmp = isALNUM(i); |
a687059c |
328 | } |
329 | else |
ac58e20f |
330 | tmp = isALNUM(regprev); /* assume not alphanumeric */ |
a687059c |
331 | while (s < strend) { |
332 | i = *s; |
ac58e20f |
333 | if (tmp != isALNUM(i)) |
a687059c |
334 | tmp = !tmp; |
335 | else if (regtry(prog, s)) |
336 | goto got_it; |
337 | s++; |
338 | } |
ae986130 |
339 | if ((minlen || !tmp) && regtry(prog,s)) |
a687059c |
340 | goto got_it; |
341 | break; |
342 | case ALNUM: |
343 | while (s < strend) { |
344 | i = *s; |
00bf170e |
345 | if (isALNUM(i)) { |
346 | if (tmp && regtry(prog, s)) |
a687059c |
347 | goto got_it; |
00bf170e |
348 | else |
349 | tmp = doevery; |
350 | } |
351 | else |
352 | tmp = 1; |
a687059c |
353 | s++; |
354 | } |
355 | break; |
356 | case NALNUM: |
357 | while (s < strend) { |
358 | i = *s; |
00bf170e |
359 | if (!isALNUM(i)) { |
360 | if (tmp && regtry(prog, s)) |
a687059c |
361 | goto got_it; |
00bf170e |
362 | else |
363 | tmp = doevery; |
364 | } |
365 | else |
366 | tmp = 1; |
a687059c |
367 | s++; |
368 | } |
369 | break; |
370 | case SPACE: |
371 | while (s < strend) { |
00bf170e |
372 | if (isSPACE(*s)) { |
373 | if (tmp && regtry(prog, s)) |
a687059c |
374 | goto got_it; |
00bf170e |
375 | else |
376 | tmp = doevery; |
377 | } |
378 | else |
379 | tmp = 1; |
a687059c |
380 | s++; |
381 | } |
382 | break; |
383 | case NSPACE: |
384 | while (s < strend) { |
00bf170e |
385 | if (!isSPACE(*s)) { |
386 | if (tmp && regtry(prog, s)) |
a687059c |
387 | goto got_it; |
00bf170e |
388 | else |
389 | tmp = doevery; |
390 | } |
391 | else |
392 | tmp = 1; |
a687059c |
393 | s++; |
394 | } |
395 | break; |
396 | case DIGIT: |
397 | while (s < strend) { |
00bf170e |
398 | if (isDIGIT(*s)) { |
399 | if (tmp && regtry(prog, s)) |
a687059c |
400 | goto got_it; |
00bf170e |
401 | else |
402 | tmp = doevery; |
403 | } |
404 | else |
405 | tmp = 1; |
a687059c |
406 | s++; |
407 | } |
408 | break; |
409 | case NDIGIT: |
410 | while (s < strend) { |
00bf170e |
411 | if (!isDIGIT(*s)) { |
412 | if (tmp && regtry(prog, s)) |
a687059c |
413 | goto got_it; |
00bf170e |
414 | else |
415 | tmp = doevery; |
416 | } |
417 | else |
418 | tmp = 1; |
a687059c |
419 | s++; |
420 | } |
421 | break; |
422 | } |
423 | } |
424 | else { |
663a0e37 |
425 | if (minlen) |
426 | dontbother = minlen - 1; |
a687059c |
427 | strend -= dontbother; |
428 | /* We don't know much -- general case. */ |
429 | do { |
430 | if (regtry(prog, s)) |
431 | goto got_it; |
432 | } while (s++ < strend); |
433 | } |
434 | |
435 | /* Failure. */ |
436 | goto phooey; |
437 | |
438 | got_it: |
439 | if ((!safebase && (prog->nparens || sawampersand)) || prog->do_folding){ |
440 | strend += dontbother; /* uncheat */ |
441 | if (safebase) /* no need for $digit later */ |
442 | s = strbeg; |
443 | else if (strbeg != prog->subbase) { |
444 | i = strend - string + (stringarg - strbeg); |
445 | s = nsavestr(strbeg,i); /* so $digit will work later */ |
446 | if (prog->subbase) |
447 | Safefree(prog->subbase); |
448 | prog->subbase = s; |
00bf170e |
449 | prog->subend = s+i; |
a687059c |
450 | } |
451 | else |
452 | s = prog->subbase; |
453 | s += (stringarg - strbeg); |
454 | for (i = 0; i <= prog->nparens; i++) { |
455 | if (prog->endp[i]) { |
456 | prog->startp[i] = s + (prog->startp[i] - string); |
457 | prog->endp[i] = s + (prog->endp[i] - string); |
458 | } |
459 | } |
460 | if (prog->do_folding) |
461 | Safefree(string); |
462 | } |
463 | return(1); |
464 | |
465 | phooey: |
466 | if (prog->do_folding) |
467 | Safefree(string); |
468 | return(0); |
469 | } |
470 | |
471 | /* |
472 | - regtry - try match at specific point |
473 | */ |
474 | static int /* 0 failure, 1 success */ |
475 | regtry(prog, string) |
476 | regexp *prog; |
477 | char *string; |
478 | { |
479 | register int i; |
480 | register char **sp; |
481 | register char **ep; |
482 | |
483 | reginput = string; |
484 | regstartp = prog->startp; |
485 | regendp = prog->endp; |
486 | reglastparen = &prog->lastparen; |
487 | prog->lastparen = 0; |
488 | |
489 | sp = prog->startp; |
490 | ep = prog->endp; |
491 | if (prog->nparens) { |
492 | for (i = NSUBEXP; i > 0; i--) { |
493 | *sp++ = NULL; |
494 | *ep++ = NULL; |
495 | } |
496 | } |
497 | if (regmatch(prog->program + 1) && reginput >= regtill) { |
498 | prog->startp[0] = string; |
499 | prog->endp[0] = reginput; |
500 | return(1); |
501 | } else |
502 | return(0); |
503 | } |
504 | |
505 | /* |
506 | - regmatch - main matching routine |
507 | * |
508 | * Conceptually the strategy is simple: check to see whether the current |
509 | * node matches, call self recursively to see whether the rest matches, |
510 | * and then act accordingly. In practice we make some effort to avoid |
511 | * recursion, in particular by going through "ordinary" nodes (that don't |
512 | * need to know whether the rest of the match failed) by a loop instead of |
513 | * by recursion. |
514 | */ |
515 | /* [lwall] I've hoisted the register declarations to the outer block in order to |
516 | * maybe save a little bit of pushing and popping on the stack. It also takes |
517 | * advantage of machines that use a register save mask on subroutine entry. |
518 | */ |
519 | static int /* 0 failure, 1 success */ |
520 | regmatch(prog) |
521 | char *prog; |
522 | { |
523 | register char *scan; /* Current node. */ |
524 | char *next; /* Next node. */ |
525 | register int nextchar; |
526 | register int n; /* no or next */ |
527 | register int ln; /* len or last */ |
528 | register char *s; /* operand or save */ |
529 | register char *locinput = reginput; |
530 | |
531 | nextchar = *locinput; |
532 | scan = prog; |
533 | #ifdef DEBUGGING |
534 | if (scan != NULL && regnarrate) |
535 | fprintf(stderr, "%s(\n", regprop(scan)); |
536 | #endif |
537 | while (scan != NULL) { |
538 | #ifdef DEBUGGING |
539 | if (regnarrate) |
540 | fprintf(stderr, "%s...\n", regprop(scan)); |
541 | #endif |
542 | |
543 | #ifdef REGALIGN |
544 | next = scan + NEXT(scan); |
545 | if (next == scan) |
546 | next = NULL; |
547 | #else |
548 | next = regnext(scan); |
549 | #endif |
550 | |
551 | switch (OP(scan)) { |
552 | case BOL: |
ac58e20f |
553 | if (locinput == regbol ? regprev == '\n' : |
a687059c |
554 | ((nextchar || locinput < regeol) && |
555 | locinput[-1] == '\n') ) |
556 | { |
00bf170e |
557 | regtill = regbol; |
a687059c |
558 | break; |
559 | } |
560 | return(0); |
561 | case EOL: |
562 | if ((nextchar || locinput < regeol) && nextchar != '\n') |
563 | return(0); |
00bf170e |
564 | if (!multiline && regeol - locinput > 1) |
565 | return 0; |
566 | regtill = regbol; |
a687059c |
567 | break; |
568 | case ANY: |
569 | if ((nextchar == '\0' && locinput >= regeol) || |
570 | nextchar == '\n') |
571 | return(0); |
572 | nextchar = *++locinput; |
573 | break; |
574 | case EXACTLY: |
575 | s = OPERAND(scan); |
576 | ln = *s++; |
577 | /* Inline the first character, for speed. */ |
578 | if (*s != nextchar) |
579 | return(0); |
00bf170e |
580 | if (regeol - locinput < ln) |
a687059c |
581 | return 0; |
582 | if (ln > 1 && bcmp(s, locinput, ln) != 0) |
583 | return(0); |
584 | locinput += ln; |
585 | nextchar = *locinput; |
586 | break; |
587 | case ANYOF: |
a687059c |
588 | s = OPERAND(scan); |
589 | if (nextchar < 0) |
590 | nextchar = UCHARAT(locinput); |
591 | if (s[nextchar >> 3] & (1 << (nextchar&7))) |
592 | return(0); |
593 | nextchar = *++locinput; |
594 | if (!nextchar && locinput > regeol) |
595 | return 0; |
596 | break; |
597 | case ALNUM: |
598 | if (!nextchar) |
599 | return(0); |
ac58e20f |
600 | if (!isALNUM(nextchar)) |
a687059c |
601 | return(0); |
602 | nextchar = *++locinput; |
603 | break; |
604 | case NALNUM: |
605 | if (!nextchar && locinput >= regeol) |
606 | return(0); |
ac58e20f |
607 | if (isALNUM(nextchar)) |
a687059c |
608 | return(0); |
609 | nextchar = *++locinput; |
610 | break; |
611 | case NBOUND: |
612 | case BOUND: |
613 | if (locinput == regbol) /* was last char in word? */ |
ac58e20f |
614 | ln = isALNUM(regprev); |
a687059c |
615 | else |
ac58e20f |
616 | ln = isALNUM(locinput[-1]); |
617 | n = isALNUM(nextchar); /* is next char in word? */ |
a687059c |
618 | if ((ln == n) == (OP(scan) == BOUND)) |
619 | return(0); |
620 | break; |
621 | case SPACE: |
622 | if (!nextchar && locinput >= regeol) |
623 | return(0); |
ac58e20f |
624 | if (!isSPACE(nextchar)) |
a687059c |
625 | return(0); |
626 | nextchar = *++locinput; |
627 | break; |
628 | case NSPACE: |
629 | if (!nextchar) |
630 | return(0); |
ac58e20f |
631 | if (isSPACE(nextchar)) |
a687059c |
632 | return(0); |
633 | nextchar = *++locinput; |
634 | break; |
635 | case DIGIT: |
ac58e20f |
636 | if (!isDIGIT(nextchar)) |
a687059c |
637 | return(0); |
638 | nextchar = *++locinput; |
639 | break; |
640 | case NDIGIT: |
641 | if (!nextchar && locinput >= regeol) |
642 | return(0); |
ac58e20f |
643 | if (isDIGIT(nextchar)) |
a687059c |
644 | return(0); |
645 | nextchar = *++locinput; |
646 | break; |
647 | case REF: |
648 | case REF+1: |
649 | case REF+2: |
650 | case REF+3: |
651 | case REF+4: |
652 | case REF+5: |
653 | case REF+6: |
654 | case REF+7: |
655 | case REF+8: |
656 | case REF+9: |
657 | n = OP(scan) - REF; |
658 | s = regmystartp[n]; |
659 | if (!s) |
660 | return(0); |
661 | if (!regmyendp[n]) |
662 | return(0); |
663 | if (s == regmyendp[n]) |
664 | break; |
665 | /* Inline the first character, for speed. */ |
666 | if (*s != nextchar) |
667 | return(0); |
668 | ln = regmyendp[n] - s; |
669 | if (locinput + ln > regeol) |
670 | return 0; |
671 | if (ln > 1 && bcmp(s, locinput, ln) != 0) |
672 | return(0); |
673 | locinput += ln; |
674 | nextchar = *locinput; |
675 | break; |
676 | |
677 | case NOTHING: |
678 | break; |
679 | case BACK: |
680 | break; |
681 | case OPEN+1: |
682 | case OPEN+2: |
683 | case OPEN+3: |
684 | case OPEN+4: |
685 | case OPEN+5: |
686 | case OPEN+6: |
687 | case OPEN+7: |
688 | case OPEN+8: |
689 | case OPEN+9: |
690 | n = OP(scan) - OPEN; |
691 | reginput = locinput; |
692 | |
693 | regmystartp[n] = locinput; /* for REF */ |
694 | if (regmatch(next)) { |
695 | /* |
696 | * Don't set startp if some later |
697 | * invocation of the same parentheses |
698 | * already has. |
699 | */ |
700 | if (regstartp[n] == NULL) |
701 | regstartp[n] = locinput; |
702 | return(1); |
703 | } else |
704 | return(0); |
705 | /* NOTREACHED */ |
706 | case CLOSE+1: |
707 | case CLOSE+2: |
708 | case CLOSE+3: |
709 | case CLOSE+4: |
710 | case CLOSE+5: |
711 | case CLOSE+6: |
712 | case CLOSE+7: |
713 | case CLOSE+8: |
714 | case CLOSE+9: { |
715 | n = OP(scan) - CLOSE; |
716 | reginput = locinput; |
717 | |
718 | regmyendp[n] = locinput; /* for REF */ |
719 | if (regmatch(next)) { |
720 | /* |
721 | * Don't set endp if some later |
722 | * invocation of the same parentheses |
723 | * already has. |
724 | */ |
725 | if (regendp[n] == NULL) { |
726 | regendp[n] = locinput; |
727 | if (n > *reglastparen) |
728 | *reglastparen = n; |
729 | } |
730 | return(1); |
731 | } else |
732 | return(0); |
733 | } |
734 | /*NOTREACHED*/ |
735 | case BRANCH: { |
736 | if (OP(next) != BRANCH) /* No choice. */ |
737 | next = NEXTOPER(scan); /* Avoid recursion. */ |
738 | else { |
739 | do { |
740 | reginput = locinput; |
741 | if (regmatch(NEXTOPER(scan))) |
742 | return(1); |
743 | #ifdef REGALIGN |
744 | if (n = NEXT(scan)) |
745 | scan += n; |
746 | else |
747 | scan = NULL; |
748 | #else |
749 | scan = regnext(scan); |
750 | #endif |
751 | } while (scan != NULL && OP(scan) == BRANCH); |
752 | return(0); |
753 | /* NOTREACHED */ |
754 | } |
755 | } |
756 | break; |
00bf170e |
757 | case CURLY: |
758 | ln = ARG1(scan); /* min to match */ |
759 | n = ARG2(scan); /* max to match */ |
760 | scan = NEXTOPER(scan) + 4; |
761 | goto repeat; |
a687059c |
762 | case STAR: |
00bf170e |
763 | ln = 0; |
764 | n = 0; |
765 | scan = NEXTOPER(scan); |
766 | goto repeat; |
a687059c |
767 | case PLUS: |
768 | /* |
769 | * Lookahead to avoid useless match attempts |
770 | * when we know what character comes next. |
771 | */ |
00bf170e |
772 | ln = 1; |
773 | n = 0; |
774 | scan = NEXTOPER(scan); |
775 | repeat: |
a687059c |
776 | if (OP(next) == EXACTLY) |
777 | nextchar = *(OPERAND(next)+1); |
778 | else |
779 | nextchar = -1000; |
a687059c |
780 | reginput = locinput; |
00bf170e |
781 | n = regrepeat(scan, n); |
0a12ae7d |
782 | if (!multiline && OP(next) == EOL && ln < n) |
00bf170e |
783 | ln = n; /* why back off? */ |
a687059c |
784 | while (n >= ln) { |
785 | /* If it could work, try it. */ |
786 | if (nextchar == -1000 || *reginput == nextchar) |
787 | if (regmatch(next)) |
788 | return(1); |
789 | /* Couldn't or didn't -- back up. */ |
790 | n--; |
791 | reginput = locinput + n; |
792 | } |
793 | return(0); |
794 | case END: |
795 | reginput = locinput; /* put where regtry can find it */ |
796 | return(1); /* Success! */ |
797 | default: |
798 | printf("%x %d\n",scan,scan[1]); |
799 | FAIL("regexp memory corruption"); |
800 | } |
801 | |
802 | scan = next; |
803 | } |
804 | |
805 | /* |
806 | * We get here only if there's trouble -- normally "case END" is |
807 | * the terminating point. |
808 | */ |
809 | FAIL("corrupted regexp pointers"); |
810 | /*NOTREACHED*/ |
811 | #ifdef lint |
812 | return 0; |
813 | #endif |
814 | } |
815 | |
816 | /* |
817 | - regrepeat - repeatedly match something simple, report how many |
818 | */ |
819 | /* |
820 | * [This routine now assumes that it will only match on things of length 1. |
821 | * That was true before, but now we assume scan - reginput is the count, |
822 | * rather than incrementing count on every character.] |
823 | */ |
824 | static int |
00bf170e |
825 | regrepeat(p, max) |
a687059c |
826 | char *p; |
00bf170e |
827 | int max; |
a687059c |
828 | { |
829 | register char *scan; |
830 | register char *opnd; |
831 | register int c; |
832 | register char *loceol = regeol; |
833 | |
834 | scan = reginput; |
00bf170e |
835 | if (max && max < loceol - scan) |
836 | loceol = scan + max; |
a687059c |
837 | opnd = OPERAND(p); |
838 | switch (OP(p)) { |
839 | case ANY: |
840 | while (scan < loceol && *scan != '\n') |
841 | scan++; |
842 | break; |
843 | case EXACTLY: /* length of string is 1 */ |
844 | opnd++; |
845 | while (scan < loceol && *opnd == *scan) |
846 | scan++; |
847 | break; |
848 | case ANYOF: |
a687059c |
849 | c = UCHARAT(scan); |
850 | while (scan < loceol && !(opnd[c >> 3] & (1 << (c & 7)))) { |
851 | scan++; |
852 | c = UCHARAT(scan); |
853 | } |
854 | break; |
855 | case ALNUM: |
0a12ae7d |
856 | while (scan < loceol && isALNUM(*scan)) |
a687059c |
857 | scan++; |
858 | break; |
859 | case NALNUM: |
ac58e20f |
860 | while (scan < loceol && !isALNUM(*scan)) |
a687059c |
861 | scan++; |
862 | break; |
863 | case SPACE: |
ac58e20f |
864 | while (scan < loceol && isSPACE(*scan)) |
a687059c |
865 | scan++; |
866 | break; |
867 | case NSPACE: |
ac58e20f |
868 | while (scan < loceol && !isSPACE(*scan)) |
a687059c |
869 | scan++; |
870 | break; |
871 | case DIGIT: |
0a12ae7d |
872 | while (scan < loceol && isDIGIT(*scan)) |
a687059c |
873 | scan++; |
874 | break; |
875 | case NDIGIT: |
ac58e20f |
876 | while (scan < loceol && !isDIGIT(*scan)) |
a687059c |
877 | scan++; |
878 | break; |
879 | default: /* Oh dear. Called inappropriately. */ |
880 | FAIL("internal regexp foulup"); |
881 | /* NOTREACHED */ |
882 | } |
883 | |
884 | c = scan - reginput; |
885 | reginput = scan; |
886 | |
887 | return(c); |
888 | } |
889 | |
890 | /* |
891 | - regnext - dig the "next" pointer out of a node |
892 | * |
893 | * [Note, when REGALIGN is defined there are two places in regmatch() |
894 | * that bypass this code for speed.] |
895 | */ |
896 | char * |
897 | regnext(p) |
898 | register char *p; |
899 | { |
900 | register int offset; |
901 | |
902 | if (p == ®dummy) |
903 | return(NULL); |
904 | |
905 | offset = NEXT(p); |
906 | if (offset == 0) |
907 | return(NULL); |
908 | |
909 | #ifdef REGALIGN |
910 | return(p+offset); |
911 | #else |
912 | if (OP(p) == BACK) |
913 | return(p-offset); |
914 | else |
915 | return(p+offset); |
916 | #endif |
917 | } |