Commit | Line | Data |
---|---|---|
a687059c LW |
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 | ||
9ef589d8 | 10 | /* $RCSfile: regexec.c,v $$Revision: 4.0.1.2 $$Date: 91/06/07 11:50:33 $ |
a687059c LW |
11 | * |
12 | * $Log: regexec.c,v $ | |
9ef589d8 LW |
13 | * Revision 4.0.1.2 91/06/07 11:50:33 lwall |
14 | * patch4: new copyright notice | |
15 | * patch4: // wouldn't use previous pattern if it started with a null character | |
16 | * | |
35c8bce7 LW |
17 | * Revision 4.0.1.1 91/04/12 09:07:39 lwall |
18 | * patch1: regexec only allocated space for 9 subexpresssions | |
19 | * | |
fe14fcc3 LW |
20 | * Revision 4.0 91/03/20 01:39:16 lwall |
21 | * 4.0 baseline. | |
a687059c LW |
22 | * |
23 | */ | |
24 | ||
25 | /* | |
26 | * regcomp and regexec -- regsub and regerror are not used in perl | |
27 | * | |
28 | * Copyright (c) 1986 by University of Toronto. | |
29 | * Written by Henry Spencer. Not derived from licensed software. | |
30 | * | |
31 | * Permission is granted to anyone to use this software for any | |
32 | * purpose on any computer system, and to redistribute it freely, | |
33 | * subject to the following restrictions: | |
34 | * | |
35 | * 1. The author is not responsible for the consequences of use of | |
36 | * this software, no matter how awful, even if they arise | |
37 | * from defects in it. | |
38 | * | |
39 | * 2. The origin of this software must not be misrepresented, either | |
40 | * by explicit claim or by omission. | |
41 | * | |
42 | * 3. Altered versions must be plainly marked as such, and must not | |
43 | * be misrepresented as being the original software. | |
44 | * | |
45 | **** Alterations to Henry's code are... | |
46 | **** | |
9ef589d8 | 47 | **** Copyright (c) 1991, Larry Wall |
a687059c | 48 | **** |
9ef589d8 LW |
49 | **** You may distribute under the terms of either the GNU General Public |
50 | **** License or the Artistic License, as specified in the README file. | |
a687059c LW |
51 | * |
52 | * Beware that some of this code is subtly aware of the way operator | |
53 | * precedence is structured in regular expressions. Serious changes in | |
54 | * regular-expression syntax might require a total rethink. | |
55 | */ | |
56 | #include "EXTERN.h" | |
57 | #include "perl.h" | |
58 | #include "regcomp.h" | |
59 | ||
60 | #ifndef STATIC | |
61 | #define STATIC static | |
62 | #endif | |
63 | ||
64 | #ifdef DEBUGGING | |
65 | int regnarrate = 0; | |
66 | #endif | |
67 | ||
ac58e20f LW |
68 | #define isALNUM(c) (isascii(c) && (isalpha(c) || isdigit(c) || c == '_')) |
69 | #define isSPACE(c) (isascii(c) && isspace(c)) | |
70 | #define isDIGIT(c) (isascii(c) && isdigit(c)) | |
71 | #define isUPPER(c) (isascii(c) && isupper(c)) | |
72 | ||
a687059c LW |
73 | /* |
74 | * regexec and friends | |
75 | */ | |
76 | ||
77 | /* | |
78 | * Global work variables for regexec(). | |
79 | */ | |
80 | static char *regprecomp; | |
81 | static char *reginput; /* String-input pointer. */ | |
ac58e20f | 82 | static char regprev; /* char before regbol, \n if none */ |
a687059c LW |
83 | static char *regbol; /* Beginning of input, for ^ check. */ |
84 | static char *regeol; /* End of input, for $ check. */ | |
85 | static char **regstartp; /* Pointer to startp array. */ | |
86 | static char **regendp; /* Ditto for endp. */ | |
87 | static char *reglastparen; /* Similarly for lastparen. */ | |
88 | static char *regtill; | |
89 | ||
35c8bce7 LW |
90 | static int regmyp_size = 0; |
91 | static char **regmystartp = Null(char**); | |
92 | static char **regmyendp = Null(char**); | |
a687059c LW |
93 | |
94 | /* | |
95 | * Forwards. | |
96 | */ | |
97 | STATIC int regtry(); | |
98 | STATIC int regmatch(); | |
99 | STATIC int regrepeat(); | |
100 | ||
101 | extern int multiline; | |
102 | ||
103 | /* | |
104 | - regexec - match a regexp against a string | |
105 | */ | |
106 | int | |
107 | regexec(prog, stringarg, strend, strbeg, minend, screamer, safebase) | |
108 | register regexp *prog; | |
109 | char *stringarg; | |
110 | register char *strend; /* pointer to null at end of string */ | |
111 | char *strbeg; /* real beginning of string */ | |
112 | int minend; /* end of match must be at least minend after stringarg */ | |
113 | STR *screamer; | |
114 | int safebase; /* no need to remember string in subbase */ | |
115 | { | |
116 | register char *s; | |
117 | register int i; | |
118 | register char *c; | |
119 | register char *string = stringarg; | |
120 | register int tmp; | |
121 | int minlen = 0; /* must match at least this many chars */ | |
122 | int dontbother = 0; /* how many characters not to try at end */ | |
a687059c LW |
123 | |
124 | /* Be paranoid... */ | |
125 | if (prog == NULL || string == NULL) { | |
126 | fatal("NULL regexp parameter"); | |
127 | return(0); | |
128 | } | |
129 | ||
ac58e20f LW |
130 | if (string == strbeg) /* is ^ valid at stringarg? */ |
131 | regprev = '\n'; | |
0a12ae7d | 132 | else { |
ac58e20f | 133 | regprev = stringarg[-1]; |
0a12ae7d LW |
134 | if (!multiline && regprev == '\n') |
135 | regprev = '\0'; /* force ^ to NOT match */ | |
136 | } | |
a687059c LW |
137 | regprecomp = prog->precomp; |
138 | /* Check validity of program. */ | |
139 | if (UCHARAT(prog->program) != MAGIC) { | |
140 | FAIL("corrupted regexp program"); | |
141 | } | |
142 | ||
143 | if (prog->do_folding) { | |
144 | safebase = FALSE; | |
145 | i = strend - string; | |
146 | New(1101,c,i+1,char); | |
147 | (void)bcopy(string, c, i+1); | |
148 | string = c; | |
149 | strend = string + i; | |
150 | for (s = string; s < strend; s++) | |
ac58e20f | 151 | if (isUPPER(*s)) |
a687059c LW |
152 | *s = tolower(*s); |
153 | } | |
154 | ||
155 | /* If there is a "must appear" string, look for it. */ | |
156 | s = string; | |
34de22dd | 157 | if (prog->regmust != Nullstr && |
9ef589d8 LW |
158 | (!(prog->reganch & ROPT_ANCH) |
159 | || (multiline && prog->regback >= 0)) ) { | |
ac58e20f | 160 | if (stringarg == strbeg && screamer) { |
a687059c LW |
161 | if (screamfirst[prog->regmust->str_rare] >= 0) |
162 | s = screaminstr(screamer,prog->regmust); | |
163 | else | |
164 | s = Nullch; | |
165 | } | |
166 | #ifndef lint | |
167 | else | |
168 | s = fbminstr((unsigned char*)s, (unsigned char*)strend, | |
169 | prog->regmust); | |
170 | #endif | |
171 | if (!s) { | |
172 | ++prog->regmust->str_u.str_useful; /* hooray */ | |
173 | goto phooey; /* not present */ | |
174 | } | |
175 | else if (prog->regback >= 0) { | |
176 | s -= prog->regback; | |
177 | if (s < string) | |
178 | s = string; | |
179 | minlen = prog->regback + prog->regmust->str_cur; | |
180 | } | |
181 | else if (--prog->regmust->str_u.str_useful < 0) { /* boo */ | |
182 | str_free(prog->regmust); | |
183 | prog->regmust = Nullstr; /* disable regmust */ | |
184 | s = string; | |
185 | } | |
186 | else { | |
187 | s = string; | |
188 | minlen = prog->regmust->str_cur; | |
189 | } | |
190 | } | |
191 | ||
192 | /* Mark beginning of line for ^ . */ | |
ac58e20f | 193 | regbol = string; |
a687059c LW |
194 | |
195 | /* Mark end of line for $ (and such) */ | |
196 | regeol = strend; | |
197 | ||
198 | /* see how far we have to get to not match where we matched before */ | |
199 | regtill = string+minend; | |
200 | ||
35c8bce7 LW |
201 | /* Allocate our backreference arrays */ |
202 | if ( regmyp_size < prog->nparens + 1 ) { | |
203 | /* Allocate or enlarge the arrays */ | |
204 | regmyp_size = prog->nparens + 1; | |
205 | if ( regmyp_size < 10 ) regmyp_size = 10; /* minimum */ | |
206 | if ( regmystartp ) { | |
207 | /* reallocate larger */ | |
208 | Renew(regmystartp,regmyp_size,char*); | |
209 | Renew(regmyendp, regmyp_size,char*); | |
210 | } | |
211 | else { | |
212 | /* Initial allocation */ | |
213 | New(1102,regmystartp,regmyp_size,char*); | |
214 | New(1102,regmyendp, regmyp_size,char*); | |
215 | } | |
216 | ||
217 | } | |
218 | ||
a687059c LW |
219 | /* Simplest case: anchored match need be tried only once. */ |
220 | /* [unless multiline is set] */ | |
9ef589d8 | 221 | if (prog->reganch & ROPT_ANCH) { |
a687059c LW |
222 | if (regtry(prog, string)) |
223 | goto got_it; | |
224 | else if (multiline) { | |
225 | if (minlen) | |
226 | dontbother = minlen - 1; | |
227 | strend -= dontbother; | |
228 | /* for multiline we only have to try after newlines */ | |
229 | if (s > string) | |
230 | s--; | |
00bf170e LW |
231 | while (s < strend) { |
232 | if (*s++ == '\n') { | |
233 | if (s < strend && regtry(prog, s)) | |
a687059c LW |
234 | goto got_it; |
235 | } | |
236 | } | |
237 | } | |
238 | goto phooey; | |
239 | } | |
240 | ||
241 | /* Messy cases: unanchored match. */ | |
242 | if (prog->regstart) { | |
9ef589d8 | 243 | if (prog->reganch & ROPT_SKIP) { /* we have /x+whatever/ */ |
00bf170e LW |
244 | /* it must be a one character string */ |
245 | i = prog->regstart->str_ptr[0]; | |
246 | while (s < strend) { | |
247 | if (*s == i) { | |
248 | if (regtry(prog, s)) | |
249 | goto got_it; | |
250 | s++; | |
251 | while (s < strend && *s == i) | |
252 | s++; | |
253 | } | |
254 | s++; | |
255 | } | |
256 | } | |
257 | else if (prog->regstart->str_pok == 3) { | |
258 | /* We know what string it must start with. */ | |
a687059c LW |
259 | #ifndef lint |
260 | while ((s = fbminstr((unsigned char*)s, | |
261 | (unsigned char*)strend, prog->regstart)) != NULL) | |
262 | #else | |
263 | while (s = Nullch) | |
264 | #endif | |
265 | { | |
266 | if (regtry(prog, s)) | |
267 | goto got_it; | |
268 | s++; | |
269 | } | |
270 | } | |
271 | else { | |
272 | c = prog->regstart->str_ptr; | |
273 | while ((s = ninstr(s, strend, | |
274 | c, c + prog->regstart->str_cur )) != NULL) { | |
275 | if (regtry(prog, s)) | |
276 | goto got_it; | |
277 | s++; | |
278 | } | |
279 | } | |
280 | goto phooey; | |
281 | } | |
282 | if (c = prog->regstclass) { | |
9ef589d8 | 283 | int doevery = (prog->reganch & ROPT_SKIP) == 0; |
00bf170e | 284 | |
a687059c LW |
285 | if (minlen) |
286 | dontbother = minlen - 1; | |
287 | strend -= dontbother; /* don't bother with what can't match */ | |
00bf170e | 288 | tmp = 1; |
a687059c LW |
289 | /* We know what class it must start with. */ |
290 | switch (OP(c)) { | |
00bf170e | 291 | case ANYOF: |
a687059c LW |
292 | c = OPERAND(c); |
293 | while (s < strend) { | |
ac58e20f | 294 | i = UCHARAT(s); |
00bf170e LW |
295 | if (!(c[i >> 3] & (1 << (i&7)))) { |
296 | if (tmp && regtry(prog, s)) | |
a687059c | 297 | goto got_it; |
00bf170e LW |
298 | else |
299 | tmp = doevery; | |
300 | } | |
301 | else | |
302 | tmp = 1; | |
a687059c LW |
303 | s++; |
304 | } | |
305 | break; | |
306 | case BOUND: | |
307 | if (minlen) | |
308 | dontbother++,strend--; | |
309 | if (s != string) { | |
310 | i = s[-1]; | |
ac58e20f | 311 | tmp = isALNUM(i); |
a687059c LW |
312 | } |
313 | else | |
ac58e20f | 314 | tmp = isALNUM(regprev); /* assume not alphanumeric */ |
a687059c LW |
315 | while (s < strend) { |
316 | i = *s; | |
ac58e20f | 317 | if (tmp != isALNUM(i)) { |
a687059c LW |
318 | tmp = !tmp; |
319 | if (regtry(prog, s)) | |
320 | goto got_it; | |
321 | } | |
322 | s++; | |
323 | } | |
ae986130 | 324 | if ((minlen || tmp) && regtry(prog,s)) |
a687059c LW |
325 | goto got_it; |
326 | break; | |
327 | case NBOUND: | |
328 | if (minlen) | |
329 | dontbother++,strend--; | |
330 | if (s != string) { | |
331 | i = s[-1]; | |
ac58e20f | 332 | tmp = isALNUM(i); |
a687059c LW |
333 | } |
334 | else | |
ac58e20f | 335 | tmp = isALNUM(regprev); /* assume not alphanumeric */ |
a687059c LW |
336 | while (s < strend) { |
337 | i = *s; | |
ac58e20f | 338 | if (tmp != isALNUM(i)) |
a687059c LW |
339 | tmp = !tmp; |
340 | else if (regtry(prog, s)) | |
341 | goto got_it; | |
342 | s++; | |
343 | } | |
ae986130 | 344 | if ((minlen || !tmp) && regtry(prog,s)) |
a687059c LW |
345 | goto got_it; |
346 | break; | |
347 | case ALNUM: | |
348 | while (s < strend) { | |
349 | i = *s; | |
00bf170e LW |
350 | if (isALNUM(i)) { |
351 | if (tmp && regtry(prog, s)) | |
a687059c | 352 | goto got_it; |
00bf170e LW |
353 | else |
354 | tmp = doevery; | |
355 | } | |
356 | else | |
357 | tmp = 1; | |
a687059c LW |
358 | s++; |
359 | } | |
360 | break; | |
361 | case NALNUM: | |
362 | while (s < strend) { | |
363 | i = *s; | |
00bf170e LW |
364 | if (!isALNUM(i)) { |
365 | if (tmp && regtry(prog, s)) | |
a687059c | 366 | goto got_it; |
00bf170e LW |
367 | else |
368 | tmp = doevery; | |
369 | } | |
370 | else | |
371 | tmp = 1; | |
a687059c LW |
372 | s++; |
373 | } | |
374 | break; | |
375 | case SPACE: | |
376 | while (s < strend) { | |
00bf170e LW |
377 | if (isSPACE(*s)) { |
378 | if (tmp && regtry(prog, s)) | |
a687059c | 379 | goto got_it; |
00bf170e LW |
380 | else |
381 | tmp = doevery; | |
382 | } | |
383 | else | |
384 | tmp = 1; | |
a687059c LW |
385 | s++; |
386 | } | |
387 | break; | |
388 | case NSPACE: | |
389 | while (s < strend) { | |
00bf170e LW |
390 | if (!isSPACE(*s)) { |
391 | if (tmp && regtry(prog, s)) | |
a687059c | 392 | goto got_it; |
00bf170e LW |
393 | else |
394 | tmp = doevery; | |
395 | } | |
396 | else | |
397 | tmp = 1; | |
a687059c LW |
398 | s++; |
399 | } | |
400 | break; | |
401 | case DIGIT: | |
402 | while (s < strend) { | |
00bf170e LW |
403 | if (isDIGIT(*s)) { |
404 | if (tmp && regtry(prog, s)) | |
a687059c | 405 | goto got_it; |
00bf170e LW |
406 | else |
407 | tmp = doevery; | |
408 | } | |
409 | else | |
410 | tmp = 1; | |
a687059c LW |
411 | s++; |
412 | } | |
413 | break; | |
414 | case NDIGIT: | |
415 | while (s < strend) { | |
00bf170e LW |
416 | if (!isDIGIT(*s)) { |
417 | if (tmp && regtry(prog, s)) | |
a687059c | 418 | goto got_it; |
00bf170e LW |
419 | else |
420 | tmp = doevery; | |
421 | } | |
422 | else | |
423 | tmp = 1; | |
a687059c LW |
424 | s++; |
425 | } | |
426 | break; | |
427 | } | |
428 | } | |
429 | else { | |
663a0e37 LW |
430 | if (minlen) |
431 | dontbother = minlen - 1; | |
a687059c LW |
432 | strend -= dontbother; |
433 | /* We don't know much -- general case. */ | |
434 | do { | |
435 | if (regtry(prog, s)) | |
436 | goto got_it; | |
437 | } while (s++ < strend); | |
438 | } | |
439 | ||
440 | /* Failure. */ | |
441 | goto phooey; | |
442 | ||
443 | got_it: | |
444 | if ((!safebase && (prog->nparens || sawampersand)) || prog->do_folding){ | |
445 | strend += dontbother; /* uncheat */ | |
446 | if (safebase) /* no need for $digit later */ | |
447 | s = strbeg; | |
448 | else if (strbeg != prog->subbase) { | |
449 | i = strend - string + (stringarg - strbeg); | |
450 | s = nsavestr(strbeg,i); /* so $digit will work later */ | |
451 | if (prog->subbase) | |
452 | Safefree(prog->subbase); | |
9ef589d8 | 453 | prog->subbeg = prog->subbase = s; |
00bf170e | 454 | prog->subend = s+i; |
a687059c LW |
455 | } |
456 | else | |
457 | s = prog->subbase; | |
458 | s += (stringarg - strbeg); | |
459 | for (i = 0; i <= prog->nparens; i++) { | |
460 | if (prog->endp[i]) { | |
461 | prog->startp[i] = s + (prog->startp[i] - string); | |
462 | prog->endp[i] = s + (prog->endp[i] - string); | |
463 | } | |
464 | } | |
465 | if (prog->do_folding) | |
466 | Safefree(string); | |
467 | } | |
468 | return(1); | |
469 | ||
470 | phooey: | |
471 | if (prog->do_folding) | |
472 | Safefree(string); | |
473 | return(0); | |
474 | } | |
475 | ||
476 | /* | |
477 | - regtry - try match at specific point | |
478 | */ | |
479 | static int /* 0 failure, 1 success */ | |
480 | regtry(prog, string) | |
481 | regexp *prog; | |
482 | char *string; | |
483 | { | |
484 | register int i; | |
485 | register char **sp; | |
486 | register char **ep; | |
487 | ||
488 | reginput = string; | |
489 | regstartp = prog->startp; | |
490 | regendp = prog->endp; | |
491 | reglastparen = &prog->lastparen; | |
492 | prog->lastparen = 0; | |
493 | ||
494 | sp = prog->startp; | |
495 | ep = prog->endp; | |
496 | if (prog->nparens) { | |
fe14fcc3 | 497 | for (i = prog->nparens; i >= 0; i--) { |
a687059c LW |
498 | *sp++ = NULL; |
499 | *ep++ = NULL; | |
500 | } | |
501 | } | |
502 | if (regmatch(prog->program + 1) && reginput >= regtill) { | |
503 | prog->startp[0] = string; | |
504 | prog->endp[0] = reginput; | |
505 | return(1); | |
506 | } else | |
507 | return(0); | |
508 | } | |
509 | ||
510 | /* | |
511 | - regmatch - main matching routine | |
512 | * | |
513 | * Conceptually the strategy is simple: check to see whether the current | |
514 | * node matches, call self recursively to see whether the rest matches, | |
515 | * and then act accordingly. In practice we make some effort to avoid | |
516 | * recursion, in particular by going through "ordinary" nodes (that don't | |
517 | * need to know whether the rest of the match failed) by a loop instead of | |
518 | * by recursion. | |
519 | */ | |
520 | /* [lwall] I've hoisted the register declarations to the outer block in order to | |
521 | * maybe save a little bit of pushing and popping on the stack. It also takes | |
522 | * advantage of machines that use a register save mask on subroutine entry. | |
523 | */ | |
524 | static int /* 0 failure, 1 success */ | |
525 | regmatch(prog) | |
526 | char *prog; | |
527 | { | |
528 | register char *scan; /* Current node. */ | |
529 | char *next; /* Next node. */ | |
530 | register int nextchar; | |
531 | register int n; /* no or next */ | |
532 | register int ln; /* len or last */ | |
533 | register char *s; /* operand or save */ | |
534 | register char *locinput = reginput; | |
535 | ||
536 | nextchar = *locinput; | |
537 | scan = prog; | |
538 | #ifdef DEBUGGING | |
539 | if (scan != NULL && regnarrate) | |
540 | fprintf(stderr, "%s(\n", regprop(scan)); | |
541 | #endif | |
542 | while (scan != NULL) { | |
543 | #ifdef DEBUGGING | |
544 | if (regnarrate) | |
545 | fprintf(stderr, "%s...\n", regprop(scan)); | |
546 | #endif | |
547 | ||
548 | #ifdef REGALIGN | |
549 | next = scan + NEXT(scan); | |
550 | if (next == scan) | |
551 | next = NULL; | |
552 | #else | |
553 | next = regnext(scan); | |
554 | #endif | |
555 | ||
556 | switch (OP(scan)) { | |
557 | case BOL: | |
ac58e20f | 558 | if (locinput == regbol ? regprev == '\n' : |
a687059c LW |
559 | ((nextchar || locinput < regeol) && |
560 | locinput[-1] == '\n') ) | |
561 | { | |
fe14fcc3 | 562 | /* regtill = regbol; */ |
a687059c LW |
563 | break; |
564 | } | |
565 | return(0); | |
566 | case EOL: | |
567 | if ((nextchar || locinput < regeol) && nextchar != '\n') | |
568 | return(0); | |
00bf170e LW |
569 | if (!multiline && regeol - locinput > 1) |
570 | return 0; | |
fe14fcc3 | 571 | /* regtill = regbol; */ |
a687059c LW |
572 | break; |
573 | case ANY: | |
574 | if ((nextchar == '\0' && locinput >= regeol) || | |
575 | nextchar == '\n') | |
576 | return(0); | |
577 | nextchar = *++locinput; | |
578 | break; | |
579 | case EXACTLY: | |
580 | s = OPERAND(scan); | |
581 | ln = *s++; | |
582 | /* Inline the first character, for speed. */ | |
583 | if (*s != nextchar) | |
584 | return(0); | |
00bf170e | 585 | if (regeol - locinput < ln) |
a687059c LW |
586 | return 0; |
587 | if (ln > 1 && bcmp(s, locinput, ln) != 0) | |
588 | return(0); | |
589 | locinput += ln; | |
590 | nextchar = *locinput; | |
591 | break; | |
592 | case ANYOF: | |
a687059c LW |
593 | s = OPERAND(scan); |
594 | if (nextchar < 0) | |
595 | nextchar = UCHARAT(locinput); | |
596 | if (s[nextchar >> 3] & (1 << (nextchar&7))) | |
597 | return(0); | |
34de22dd | 598 | if (!nextchar && locinput >= regeol) |
a687059c | 599 | return 0; |
34de22dd | 600 | nextchar = *++locinput; |
a687059c LW |
601 | break; |
602 | case ALNUM: | |
603 | if (!nextchar) | |
604 | return(0); | |
ac58e20f | 605 | if (!isALNUM(nextchar)) |
a687059c LW |
606 | return(0); |
607 | nextchar = *++locinput; | |
608 | break; | |
609 | case NALNUM: | |
610 | if (!nextchar && locinput >= regeol) | |
611 | return(0); | |
ac58e20f | 612 | if (isALNUM(nextchar)) |
a687059c LW |
613 | return(0); |
614 | nextchar = *++locinput; | |
615 | break; | |
616 | case NBOUND: | |
617 | case BOUND: | |
618 | if (locinput == regbol) /* was last char in word? */ | |
ac58e20f | 619 | ln = isALNUM(regprev); |
a687059c | 620 | else |
ac58e20f LW |
621 | ln = isALNUM(locinput[-1]); |
622 | n = isALNUM(nextchar); /* is next char in word? */ | |
a687059c LW |
623 | if ((ln == n) == (OP(scan) == BOUND)) |
624 | return(0); | |
625 | break; | |
626 | case SPACE: | |
627 | if (!nextchar && locinput >= regeol) | |
628 | return(0); | |
ac58e20f | 629 | if (!isSPACE(nextchar)) |
a687059c LW |
630 | return(0); |
631 | nextchar = *++locinput; | |
632 | break; | |
633 | case NSPACE: | |
634 | if (!nextchar) | |
635 | return(0); | |
ac58e20f | 636 | if (isSPACE(nextchar)) |
a687059c LW |
637 | return(0); |
638 | nextchar = *++locinput; | |
639 | break; | |
640 | case DIGIT: | |
ac58e20f | 641 | if (!isDIGIT(nextchar)) |
a687059c LW |
642 | return(0); |
643 | nextchar = *++locinput; | |
644 | break; | |
645 | case NDIGIT: | |
646 | if (!nextchar && locinput >= regeol) | |
647 | return(0); | |
ac58e20f | 648 | if (isDIGIT(nextchar)) |
a687059c LW |
649 | return(0); |
650 | nextchar = *++locinput; | |
651 | break; | |
652 | case REF: | |
fe14fcc3 | 653 | n = ARG1(scan); /* which paren pair */ |
a687059c LW |
654 | s = regmystartp[n]; |
655 | if (!s) | |
656 | return(0); | |
657 | if (!regmyendp[n]) | |
658 | return(0); | |
659 | if (s == regmyendp[n]) | |
660 | break; | |
661 | /* Inline the first character, for speed. */ | |
662 | if (*s != nextchar) | |
663 | return(0); | |
664 | ln = regmyendp[n] - s; | |
665 | if (locinput + ln > regeol) | |
666 | return 0; | |
667 | if (ln > 1 && bcmp(s, locinput, ln) != 0) | |
668 | return(0); | |
669 | locinput += ln; | |
670 | nextchar = *locinput; | |
671 | break; | |
672 | ||
673 | case NOTHING: | |
674 | break; | |
675 | case BACK: | |
676 | break; | |
fe14fcc3 LW |
677 | case OPEN: |
678 | n = ARG1(scan); /* which paren pair */ | |
a687059c LW |
679 | reginput = locinput; |
680 | ||
681 | regmystartp[n] = locinput; /* for REF */ | |
682 | if (regmatch(next)) { | |
683 | /* | |
684 | * Don't set startp if some later | |
685 | * invocation of the same parentheses | |
686 | * already has. | |
687 | */ | |
688 | if (regstartp[n] == NULL) | |
689 | regstartp[n] = locinput; | |
690 | return(1); | |
691 | } else | |
692 | return(0); | |
693 | /* NOTREACHED */ | |
fe14fcc3 LW |
694 | case CLOSE: { |
695 | n = ARG1(scan); /* which paren pair */ | |
a687059c LW |
696 | reginput = locinput; |
697 | ||
698 | regmyendp[n] = locinput; /* for REF */ | |
699 | if (regmatch(next)) { | |
700 | /* | |
701 | * Don't set endp if some later | |
702 | * invocation of the same parentheses | |
703 | * already has. | |
704 | */ | |
705 | if (regendp[n] == NULL) { | |
706 | regendp[n] = locinput; | |
707 | if (n > *reglastparen) | |
708 | *reglastparen = n; | |
709 | } | |
710 | return(1); | |
711 | } else | |
712 | return(0); | |
713 | } | |
714 | /*NOTREACHED*/ | |
715 | case BRANCH: { | |
716 | if (OP(next) != BRANCH) /* No choice. */ | |
717 | next = NEXTOPER(scan); /* Avoid recursion. */ | |
718 | else { | |
719 | do { | |
720 | reginput = locinput; | |
721 | if (regmatch(NEXTOPER(scan))) | |
722 | return(1); | |
723 | #ifdef REGALIGN | |
724 | if (n = NEXT(scan)) | |
725 | scan += n; | |
726 | else | |
727 | scan = NULL; | |
728 | #else | |
729 | scan = regnext(scan); | |
730 | #endif | |
731 | } while (scan != NULL && OP(scan) == BRANCH); | |
732 | return(0); | |
733 | /* NOTREACHED */ | |
734 | } | |
735 | } | |
736 | break; | |
00bf170e LW |
737 | case CURLY: |
738 | ln = ARG1(scan); /* min to match */ | |
739 | n = ARG2(scan); /* max to match */ | |
740 | scan = NEXTOPER(scan) + 4; | |
741 | goto repeat; | |
a687059c | 742 | case STAR: |
00bf170e LW |
743 | ln = 0; |
744 | n = 0; | |
745 | scan = NEXTOPER(scan); | |
746 | goto repeat; | |
a687059c LW |
747 | case PLUS: |
748 | /* | |
749 | * Lookahead to avoid useless match attempts | |
750 | * when we know what character comes next. | |
751 | */ | |
00bf170e LW |
752 | ln = 1; |
753 | n = 0; | |
754 | scan = NEXTOPER(scan); | |
755 | repeat: | |
a687059c LW |
756 | if (OP(next) == EXACTLY) |
757 | nextchar = *(OPERAND(next)+1); | |
758 | else | |
759 | nextchar = -1000; | |
a687059c | 760 | reginput = locinput; |
00bf170e | 761 | n = regrepeat(scan, n); |
0a12ae7d | 762 | if (!multiline && OP(next) == EOL && ln < n) |
00bf170e | 763 | ln = n; /* why back off? */ |
a687059c LW |
764 | while (n >= ln) { |
765 | /* If it could work, try it. */ | |
766 | if (nextchar == -1000 || *reginput == nextchar) | |
767 | if (regmatch(next)) | |
768 | return(1); | |
769 | /* Couldn't or didn't -- back up. */ | |
770 | n--; | |
771 | reginput = locinput + n; | |
772 | } | |
773 | return(0); | |
774 | case END: | |
775 | reginput = locinput; /* put where regtry can find it */ | |
776 | return(1); /* Success! */ | |
777 | default: | |
778 | printf("%x %d\n",scan,scan[1]); | |
779 | FAIL("regexp memory corruption"); | |
780 | } | |
781 | ||
782 | scan = next; | |
783 | } | |
784 | ||
785 | /* | |
786 | * We get here only if there's trouble -- normally "case END" is | |
787 | * the terminating point. | |
788 | */ | |
789 | FAIL("corrupted regexp pointers"); | |
790 | /*NOTREACHED*/ | |
791 | #ifdef lint | |
792 | return 0; | |
793 | #endif | |
794 | } | |
795 | ||
796 | /* | |
797 | - regrepeat - repeatedly match something simple, report how many | |
798 | */ | |
799 | /* | |
800 | * [This routine now assumes that it will only match on things of length 1. | |
801 | * That was true before, but now we assume scan - reginput is the count, | |
802 | * rather than incrementing count on every character.] | |
803 | */ | |
804 | static int | |
00bf170e | 805 | regrepeat(p, max) |
a687059c | 806 | char *p; |
00bf170e | 807 | int max; |
a687059c LW |
808 | { |
809 | register char *scan; | |
810 | register char *opnd; | |
811 | register int c; | |
812 | register char *loceol = regeol; | |
813 | ||
814 | scan = reginput; | |
00bf170e LW |
815 | if (max && max < loceol - scan) |
816 | loceol = scan + max; | |
a687059c LW |
817 | opnd = OPERAND(p); |
818 | switch (OP(p)) { | |
819 | case ANY: | |
820 | while (scan < loceol && *scan != '\n') | |
821 | scan++; | |
822 | break; | |
823 | case EXACTLY: /* length of string is 1 */ | |
824 | opnd++; | |
825 | while (scan < loceol && *opnd == *scan) | |
826 | scan++; | |
827 | break; | |
828 | case ANYOF: | |
a687059c LW |
829 | c = UCHARAT(scan); |
830 | while (scan < loceol && !(opnd[c >> 3] & (1 << (c & 7)))) { | |
831 | scan++; | |
832 | c = UCHARAT(scan); | |
833 | } | |
834 | break; | |
835 | case ALNUM: | |
0a12ae7d | 836 | while (scan < loceol && isALNUM(*scan)) |
a687059c LW |
837 | scan++; |
838 | break; | |
839 | case NALNUM: | |
ac58e20f | 840 | while (scan < loceol && !isALNUM(*scan)) |
a687059c LW |
841 | scan++; |
842 | break; | |
843 | case SPACE: | |
ac58e20f | 844 | while (scan < loceol && isSPACE(*scan)) |
a687059c LW |
845 | scan++; |
846 | break; | |
847 | case NSPACE: | |
ac58e20f | 848 | while (scan < loceol && !isSPACE(*scan)) |
a687059c LW |
849 | scan++; |
850 | break; | |
851 | case DIGIT: | |
0a12ae7d | 852 | while (scan < loceol && isDIGIT(*scan)) |
a687059c LW |
853 | scan++; |
854 | break; | |
855 | case NDIGIT: | |
ac58e20f | 856 | while (scan < loceol && !isDIGIT(*scan)) |
a687059c LW |
857 | scan++; |
858 | break; | |
859 | default: /* Oh dear. Called inappropriately. */ | |
860 | FAIL("internal regexp foulup"); | |
861 | /* NOTREACHED */ | |
862 | } | |
863 | ||
864 | c = scan - reginput; | |
865 | reginput = scan; | |
866 | ||
867 | return(c); | |
868 | } | |
869 | ||
870 | /* | |
871 | - regnext - dig the "next" pointer out of a node | |
872 | * | |
873 | * [Note, when REGALIGN is defined there are two places in regmatch() | |
874 | * that bypass this code for speed.] | |
875 | */ | |
876 | char * | |
877 | regnext(p) | |
878 | register char *p; | |
879 | { | |
880 | register int offset; | |
881 | ||
882 | if (p == ®dummy) | |
883 | return(NULL); | |
884 | ||
885 | offset = NEXT(p); | |
886 | if (offset == 0) | |
887 | return(NULL); | |
888 | ||
889 | #ifdef REGALIGN | |
890 | return(p+offset); | |
891 | #else | |
892 | if (OP(p) == BACK) | |
893 | return(p-offset); | |
894 | else | |
895 | return(p+offset); | |
896 | #endif | |
897 | } |