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A new flag is set, when property checks are present in an XCLASS.
1 nigel 77 /*************************************************
2     * Perl-Compatible Regular Expressions *
3     *************************************************/
4    
5     /* PCRE is a library of functions to support regular expressions whose syntax
6     and semantics are as close as possible to those of the Perl 5 language.
7    
8     Written by Philip Hazel
9 ph10 836 Copyright (c) 1997-2012 University of Cambridge
10 nigel 77
11     -----------------------------------------------------------------------------
12     Redistribution and use in source and binary forms, with or without
13     modification, are permitted provided that the following conditions are met:
14    
15     * Redistributions of source code must retain the above copyright notice,
16     this list of conditions and the following disclaimer.
17    
18     * Redistributions in binary form must reproduce the above copyright
19     notice, this list of conditions and the following disclaimer in the
20     documentation and/or other materials provided with the distribution.
21    
22     * Neither the name of the University of Cambridge nor the names of its
23     contributors may be used to endorse or promote products derived from
24     this software without specific prior written permission.
25    
26     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27     AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28     IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29     ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30     LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31     CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32     SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33     INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36     POSSIBILITY OF SUCH DAMAGE.
37     -----------------------------------------------------------------------------
38     */
39    
40    
41     /* This module contains the external function pcre_study(), along with local
42     supporting functions. */
43    
44    
45 ph10 200 #ifdef HAVE_CONFIG_H
46 ph10 236 #include "config.h"
47 ph10 200 #endif
48 ph10 199
49 nigel 77 #include "pcre_internal.h"
50    
51 ph10 524 #define SET_BIT(c) start_bits[c/8] |= (1 << (c&7))
52 nigel 77
53 nigel 93 /* Returns from set_start_bits() */
54    
55 ph10 605 enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE, SSB_UNKNOWN };
56 nigel 93
57    
58 ph10 455
59 nigel 77 /*************************************************
60 ph10 455 * Find the minimum subject length for a group *
61     *************************************************/
62    
63     /* Scan a parenthesized group and compute the minimum length of subject that
64 ph10 461 is needed to match it. This is a lower bound; it does not mean there is a
65 ph10 455 string of that length that matches. In UTF8 mode, the result is in characters
66     rather than bytes.
67    
68     Arguments:
69 ph10 1361 re compiled pattern block
70 ph10 697 code pointer to start of group (the bracket)
71 ph10 1361 startcode pointer to start of the whole pattern's code
72 ph10 697 options the compiling options
73     int RECURSE depth
74 ph10 455
75     Returns: the minimum length
76 ph10 697 -1 if \C in UTF-8 mode or (*ACCEPT) was encountered
77 ph10 461 -2 internal error (missing capturing bracket)
78 ph10 605 -3 internal error (opcode not listed)
79 ph10 455 */
80    
81     static int
82 ph10 1404 find_minlength(const REAL_PCRE *re, const pcre_uchar *code,
83 ph10 1361 const pcre_uchar *startcode, int options, int recurse_depth)
84 ph10 455 {
85     int length = -1;
86 ph10 836 /* PCRE_UTF16 has the same value as PCRE_UTF8. */
87     BOOL utf = (options & PCRE_UTF8) != 0;
88 ph10 455 BOOL had_recurse = FALSE;
89     register int branchlength = 0;
90 ph10 836 register pcre_uchar *cc = (pcre_uchar *)code + 1 + LINK_SIZE;
91 ph10 455
92 ph10 604 if (*code == OP_CBRA || *code == OP_SCBRA ||
93 ph10 836 *code == OP_CBRAPOS || *code == OP_SCBRAPOS) cc += IMM2_SIZE;
94 ph10 455
95     /* Scan along the opcodes for this branch. If we get to the end of the
96     branch, check the length against that of the other branches. */
97    
98     for (;;)
99     {
100     int d, min;
101 ph10 836 pcre_uchar *cs, *ce;
102 chpe 1084 register pcre_uchar op = *cc;
103 ph10 461
104 ph10 455 switch (op)
105     {
106 ph10 471 case OP_COND:
107     case OP_SCOND:
108    
109     /* If there is only one branch in a condition, the implied branch has zero
110     length, so we don't add anything. This covers the DEFINE "condition"
111     automatically. */
112    
113     cs = cc + GET(cc, 1);
114     if (*cs != OP_ALT)
115     {
116     cc = cs + 1 + LINK_SIZE;
117     break;
118     }
119    
120     /* Otherwise we can fall through and treat it the same as any other
121     subpattern. */
122    
123 ph10 455 case OP_CBRA:
124 ph10 461 case OP_SCBRA:
125 ph10 455 case OP_BRA:
126 ph10 461 case OP_SBRA:
127 ph10 604 case OP_CBRAPOS:
128     case OP_SCBRAPOS:
129     case OP_BRAPOS:
130     case OP_SBRAPOS:
131 ph10 455 case OP_ONCE:
132 ph10 723 case OP_ONCE_NC:
133 ph10 1361 d = find_minlength(re, cc, startcode, options, recurse_depth);
134 ph10 455 if (d < 0) return d;
135     branchlength += d;
136     do cc += GET(cc, 1); while (*cc == OP_ALT);
137     cc += 1 + LINK_SIZE;
138     break;
139    
140 ph10 697 /* ACCEPT makes things far too complicated; we have to give up. */
141 ph10 455
142 ph10 654 case OP_ACCEPT:
143     case OP_ASSERT_ACCEPT:
144 ph10 708 return -1;
145 ph10 697
146     /* Reached end of a branch; if it's a ket it is the end of a nested
147     call. If it's ALT it is an alternation in a nested call. If it is END it's
148 ph10 708 the end of the outer call. All can be handled by the same code. If an
149     ACCEPT was previously encountered, use the length that was in force at that
150 ph10 697 time, and pass back the shortest ACCEPT length. */
151 ph10 708
152 ph10 455 case OP_ALT:
153     case OP_KET:
154     case OP_KETRMAX:
155     case OP_KETRMIN:
156 ph10 605 case OP_KETRPOS:
157 ph10 455 case OP_END:
158 ph10 461 if (length < 0 || (!had_recurse && branchlength < length))
159 ph10 455 length = branchlength;
160 ph10 612 if (op != OP_ALT) return length;
161 ph10 455 cc += 1 + LINK_SIZE;
162     branchlength = 0;
163 ph10 461 had_recurse = FALSE;
164 ph10 455 break;
165    
166     /* Skip over assertive subpatterns */
167    
168     case OP_ASSERT:
169     case OP_ASSERT_NOT:
170     case OP_ASSERTBACK:
171     case OP_ASSERTBACK_NOT:
172     do cc += GET(cc, 1); while (*cc == OP_ALT);
173     /* Fall through */
174    
175     /* Skip over things that don't match chars */
176    
177     case OP_REVERSE:
178     case OP_CREF:
179 ph10 1365 case OP_DNCREF:
180 ph10 455 case OP_RREF:
181 ph10 1365 case OP_DNRREF:
182 ph10 455 case OP_DEF:
183     case OP_CALLOUT:
184     case OP_SOD:
185     case OP_SOM:
186     case OP_EOD:
187     case OP_EODN:
188     case OP_CIRC:
189 ph10 602 case OP_CIRCM:
190 ph10 455 case OP_DOLL:
191 ph10 602 case OP_DOLLM:
192 ph10 455 case OP_NOT_WORD_BOUNDARY:
193     case OP_WORD_BOUNDARY:
194 ph10 836 cc += PRIV(OP_lengths)[*cc];
195 ph10 455 break;
196 ph10 461
197 ph10 455 /* Skip over a subpattern that has a {0} or {0,x} quantifier */
198    
199     case OP_BRAZERO:
200 ph10 461 case OP_BRAMINZERO:
201 ph10 604 case OP_BRAPOSZERO:
202 ph10 455 case OP_SKIPZERO:
203 ph10 836 cc += PRIV(OP_lengths)[*cc];
204 ph10 455 do cc += GET(cc, 1); while (*cc == OP_ALT);
205     cc += 1 + LINK_SIZE;
206     break;
207    
208     /* Handle literal characters and + repetitions */
209    
210     case OP_CHAR:
211 ph10 602 case OP_CHARI:
212 ph10 455 case OP_NOT:
213 ph10 602 case OP_NOTI:
214 ph10 455 case OP_PLUS:
215 ph10 603 case OP_PLUSI:
216 ph10 455 case OP_MINPLUS:
217 ph10 603 case OP_MINPLUSI:
218 ph10 455 case OP_POSPLUS:
219 ph10 603 case OP_POSPLUSI:
220 ph10 455 case OP_NOTPLUS:
221 ph10 603 case OP_NOTPLUSI:
222 ph10 455 case OP_NOTMINPLUS:
223 ph10 603 case OP_NOTMINPLUSI:
224 ph10 455 case OP_NOTPOSPLUS:
225 ph10 603 case OP_NOTPOSPLUSI:
226 ph10 455 branchlength++;
227     cc += 2;
228 chpe 1114 #ifdef SUPPORT_UTF
229 ph10 836 if (utf && HAS_EXTRALEN(cc[-1])) cc += GET_EXTRALEN(cc[-1]);
230 ph10 455 #endif
231     break;
232 ph10 461
233 ph10 455 case OP_TYPEPLUS:
234     case OP_TYPEMINPLUS:
235 ph10 461 case OP_TYPEPOSPLUS:
236 ph10 455 branchlength++;
237     cc += (cc[1] == OP_PROP || cc[1] == OP_NOTPROP)? 4 : 2;
238     break;
239    
240     /* Handle exact repetitions. The count is already in characters, but we
241     need to skip over a multibyte character in UTF8 mode. */
242    
243     case OP_EXACT:
244 ph10 603 case OP_EXACTI:
245 ph10 461 case OP_NOTEXACT:
246 ph10 603 case OP_NOTEXACTI:
247 ph10 455 branchlength += GET2(cc,1);
248 ph10 836 cc += 2 + IMM2_SIZE;
249 chpe 1114 #ifdef SUPPORT_UTF
250 ph10 836 if (utf && HAS_EXTRALEN(cc[-1])) cc += GET_EXTRALEN(cc[-1]);
251 ph10 455 #endif
252     break;
253    
254     case OP_TYPEEXACT:
255     branchlength += GET2(cc,1);
256 ph10 836 cc += 2 + IMM2_SIZE + ((cc[1 + IMM2_SIZE] == OP_PROP
257     || cc[1 + IMM2_SIZE] == OP_NOTPROP)? 2 : 0);
258 ph10 455 break;
259    
260     /* Handle single-char non-literal matchers */
261    
262     case OP_PROP:
263     case OP_NOTPROP:
264     cc += 2;
265     /* Fall through */
266    
267     case OP_NOT_DIGIT:
268     case OP_DIGIT:
269     case OP_NOT_WHITESPACE:
270     case OP_WHITESPACE:
271     case OP_NOT_WORDCHAR:
272     case OP_WORDCHAR:
273     case OP_ANY:
274     case OP_ALLANY:
275     case OP_EXTUNI:
276 ph10 461 case OP_HSPACE:
277 ph10 455 case OP_NOT_HSPACE:
278     case OP_VSPACE:
279 ph10 461 case OP_NOT_VSPACE:
280 ph10 455 branchlength++;
281     cc++;
282     break;
283 ph10 461
284 ph10 654 /* "Any newline" might match two characters, but it also might match just
285 ph10 611 one. */
286 ph10 461
287 ph10 455 case OP_ANYNL:
288 ph10 611 branchlength += 1;
289 ph10 455 cc++;
290 ph10 461 break;
291 ph10 455
292 ph10 836 /* The single-byte matcher means we can't proceed in UTF-8 mode. (In
293     non-UTF-8 mode \C will actually be turned into OP_ALLANY, so won't ever
294 ph10 754 appear, but leave the code, just in case.) */
295 ph10 455
296     case OP_ANYBYTE:
297 ph10 836 #ifdef SUPPORT_UTF
298     if (utf) return -1;
299 ph10 455 #endif
300     branchlength++;
301     cc++;
302 ph10 461 break;
303 ph10 455
304     /* For repeated character types, we have to test for \p and \P, which have
305     an extra two bytes of parameters. */
306    
307     case OP_TYPESTAR:
308     case OP_TYPEMINSTAR:
309     case OP_TYPEQUERY:
310     case OP_TYPEMINQUERY:
311     case OP_TYPEPOSSTAR:
312     case OP_TYPEPOSQUERY:
313     if (cc[1] == OP_PROP || cc[1] == OP_NOTPROP) cc += 2;
314 ph10 836 cc += PRIV(OP_lengths)[op];
315 ph10 455 break;
316    
317     case OP_TYPEUPTO:
318     case OP_TYPEMINUPTO:
319     case OP_TYPEPOSUPTO:
320 ph10 836 if (cc[1 + IMM2_SIZE] == OP_PROP
321     || cc[1 + IMM2_SIZE] == OP_NOTPROP) cc += 2;
322     cc += PRIV(OP_lengths)[op];
323 ph10 455 break;
324    
325     /* Check a class for variable quantification */
326    
327     case OP_CLASS:
328     case OP_NCLASS:
329 zherczeg 1148 #if defined SUPPORT_UTF || defined COMPILE_PCRE16 || defined COMPILE_PCRE32
330     case OP_XCLASS:
331     /* The original code caused an unsigned overflow in 64 bit systems,
332     so now we use a conditional statement. */
333     if (op == OP_XCLASS)
334     cc += GET(cc, 1);
335     else
336     cc += PRIV(OP_lengths)[OP_CLASS];
337     #else
338 ph10 836 cc += PRIV(OP_lengths)[OP_CLASS];
339 zherczeg 1148 #endif
340 ph10 455
341     switch (*cc)
342     {
343     case OP_CRPLUS:
344     case OP_CRMINPLUS:
345 ph10 1379 case OP_CRPOSPLUS:
346 ph10 455 branchlength++;
347 ph10 461 /* Fall through */
348 ph10 455
349     case OP_CRSTAR:
350     case OP_CRMINSTAR:
351     case OP_CRQUERY:
352     case OP_CRMINQUERY:
353 ph10 1379 case OP_CRPOSSTAR:
354     case OP_CRPOSQUERY:
355 ph10 461 cc++;
356 ph10 455 break;
357 ph10 461
358 ph10 455 case OP_CRRANGE:
359     case OP_CRMINRANGE:
360 ph10 1379 case OP_CRPOSRANGE:
361 ph10 455 branchlength += GET2(cc,1);
362 ph10 836 cc += 1 + 2 * IMM2_SIZE;
363 ph10 455 break;
364 ph10 461
365 ph10 455 default:
366     branchlength++;
367 ph10 461 break;
368 ph10 455 }
369     break;
370 ph10 461
371     /* Backreferences and subroutine calls are treated in the same way: we find
372     the minimum length for the subpattern. A recursion, however, causes an
373 ph10 455 a flag to be set that causes the length of this branch to be ignored. The
374     logic is that a recursion can only make sense if there is another
375     alternation that stops the recursing. That will provide the minimum length
376     (when no recursion happens). A backreference within the group that it is
377 ph10 469 referencing behaves in the same way.
378    
379 ph10 467 If PCRE_JAVASCRIPT_COMPAT is set, a backreference to an unset bracket
380     matches an empty string (by default it causes a matching failure), so in
381     that case we must set the minimum length to zero. */
382 ph10 1404
383 ph10 1361 case OP_DNREF: /* Duplicate named pattern back reference */
384     case OP_DNREFI:
385     if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)
386     {
387 ph10 1404 int count = GET2(cc, 1+IMM2_SIZE);
388     pcre_uchar *slot = (pcre_uchar *)re +
389 ph10 1361 re->name_table_offset + GET2(cc, 1) * re->name_entry_size;
390     d = INT_MAX;
391     while (count-- > 0)
392     {
393     ce = cs = (pcre_uchar *)PRIV(find_bracket)(startcode, utf, GET2(slot, 0));
394     if (cs == NULL) return -2;
395     do ce += GET(ce, 1); while (*ce == OP_ALT);
396     if (cc > cs && cc < ce)
397     {
398     d = 0;
399     had_recurse = TRUE;
400 ph10 1404 break;
401 ph10 1361 }
402     else
403     {
404     int dd = find_minlength(re, cs, startcode, options, recurse_depth);
405 ph10 1404 if (dd < d) d = dd;
406 ph10 1361 }
407     slot += re->name_entry_size;
408 ph10 1404 }
409 ph10 1361 }
410 ph10 1404 else d = 0;
411 ph10 1361 cc += 1 + 2*IMM2_SIZE;
412 ph10 1404 goto REPEAT_BACK_REFERENCE;
413 ph10 461
414 ph10 1361 case OP_REF: /* Single back reference */
415 ph10 602 case OP_REFI:
416 ph10 467 if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)
417 ph10 469 {
418 ph10 836 ce = cs = (pcre_uchar *)PRIV(find_bracket)(startcode, utf, GET2(cc, 1));
419 ph10 467 if (cs == NULL) return -2;
420     do ce += GET(ce, 1); while (*ce == OP_ALT);
421     if (cc > cs && cc < ce)
422     {
423     d = 0;
424     had_recurse = TRUE;
425     }
426 ph10 654 else
427 ph10 612 {
428 ph10 1361 d = find_minlength(re, cs, startcode, options, recurse_depth);
429 ph10 654 }
430 ph10 461 }
431 ph10 469 else d = 0;
432 ph10 836 cc += 1 + IMM2_SIZE;
433 ph10 455
434     /* Handle repeated back references */
435 ph10 461
436 ph10 1361 REPEAT_BACK_REFERENCE:
437 ph10 455 switch (*cc)
438     {
439     case OP_CRSTAR:
440     case OP_CRMINSTAR:
441     case OP_CRQUERY:
442     case OP_CRMINQUERY:
443 ph10 1379 case OP_CRPOSSTAR:
444     case OP_CRPOSQUERY:
445 ph10 455 min = 0;
446     cc++;
447     break;
448 ph10 605
449     case OP_CRPLUS:
450     case OP_CRMINPLUS:
451 ph10 1379 case OP_CRPOSPLUS:
452 ph10 605 min = 1;
453     cc++;
454     break;
455    
456 ph10 455 case OP_CRRANGE:
457     case OP_CRMINRANGE:
458 ph10 1379 case OP_CRPOSRANGE:
459 ph10 455 min = GET2(cc, 1);
460 ph10 836 cc += 1 + 2 * IMM2_SIZE;
461 ph10 455 break;
462 ph10 461
463 ph10 455 default:
464     min = 1;
465     break;
466     }
467    
468     branchlength += min * d;
469 ph10 461 break;
470 ph10 455
471 ph10 654 /* We can easily detect direct recursion, but not mutual recursion. This is
472     caught by a recursion depth count. */
473    
474 ph10 461 case OP_RECURSE:
475 ph10 836 cs = ce = (pcre_uchar *)startcode + GET(cc, 1);
476 ph10 455 do ce += GET(ce, 1); while (*ce == OP_ALT);
477 ph10 620 if ((cc > cs && cc < ce) || recurse_depth > 10)
478 ph10 461 had_recurse = TRUE;
479     else
480 ph10 654 {
481 ph10 1404 branchlength += find_minlength(re, cs, startcode, options,
482 ph10 1361 recurse_depth + 1);
483 ph10 654 }
484 ph10 455 cc += 1 + LINK_SIZE;
485     break;
486    
487     /* Anything else does not or need not match a character. We can get the
488 ph10 461 item's length from the table, but for those that can match zero occurrences
489 ph10 602 of a character, we must take special action for UTF-8 characters. As it
490     happens, the "NOT" versions of these opcodes are used at present only for
491     ASCII characters, so they could be omitted from this list. However, in
492 ph10 605 future that may change, so we include them here so as not to leave a
493 ph10 603 gotcha for a future maintainer. */
494 ph10 461
495 ph10 455 case OP_UPTO:
496 ph10 602 case OP_UPTOI:
497 ph10 461 case OP_NOTUPTO:
498 ph10 602 case OP_NOTUPTOI:
499 ph10 455 case OP_MINUPTO:
500 ph10 602 case OP_MINUPTOI:
501 ph10 461 case OP_NOTMINUPTO:
502 ph10 602 case OP_NOTMINUPTOI:
503 ph10 455 case OP_POSUPTO:
504 ph10 602 case OP_POSUPTOI:
505     case OP_NOTPOSUPTO:
506     case OP_NOTPOSUPTOI:
507    
508 ph10 455 case OP_STAR:
509 ph10 602 case OP_STARI:
510     case OP_NOTSTAR:
511     case OP_NOTSTARI:
512 ph10 455 case OP_MINSTAR:
513 ph10 602 case OP_MINSTARI:
514 ph10 461 case OP_NOTMINSTAR:
515 ph10 602 case OP_NOTMINSTARI:
516 ph10 455 case OP_POSSTAR:
517 ph10 602 case OP_POSSTARI:
518 ph10 461 case OP_NOTPOSSTAR:
519 ph10 602 case OP_NOTPOSSTARI:
520    
521 ph10 455 case OP_QUERY:
522 ph10 602 case OP_QUERYI:
523     case OP_NOTQUERY:
524     case OP_NOTQUERYI:
525 ph10 455 case OP_MINQUERY:
526 ph10 602 case OP_MINQUERYI:
527 ph10 455 case OP_NOTMINQUERY:
528 ph10 602 case OP_NOTMINQUERYI:
529 ph10 455 case OP_POSQUERY:
530 ph10 602 case OP_POSQUERYI:
531 ph10 461 case OP_NOTPOSQUERY:
532 ph10 602 case OP_NOTPOSQUERYI:
533    
534 ph10 836 cc += PRIV(OP_lengths)[op];
535 chpe 1114 #ifdef SUPPORT_UTF
536 ph10 836 if (utf && HAS_EXTRALEN(cc[-1])) cc += GET_EXTRALEN(cc[-1]);
537 ph10 461 #endif
538 ph10 455 break;
539 ph10 512
540 ph10 510 /* Skip these, but we need to add in the name length. */
541 ph10 512
542 ph10 510 case OP_MARK:
543     case OP_PRUNE_ARG:
544     case OP_SKIP_ARG:
545 ph10 729 case OP_THEN_ARG:
546 ph10 836 cc += PRIV(OP_lengths)[op] + cc[1];
547 ph10 512 break;
548 ph10 455
549 ph10 603 /* The remaining opcodes are just skipped over. */
550 ph10 461
551 ph10 603 case OP_CLOSE:
552     case OP_COMMIT:
553     case OP_FAIL:
554     case OP_PRUNE:
555     case OP_SET_SOM:
556     case OP_SKIP:
557 ph10 605 case OP_THEN:
558 ph10 836 cc += PRIV(OP_lengths)[op];
559 ph10 455 break;
560 ph10 605
561 ph10 603 /* This should not occur: we list all opcodes explicitly so that when
562     new ones get added they are properly considered. */
563    
564     default:
565     return -3;
566 ph10 455 }
567     }
568     /* Control never gets here */
569     }
570    
571    
572    
573     /*************************************************
574 nigel 77 * Set a bit and maybe its alternate case *
575     *************************************************/
576    
577 ph10 535 /* Given a character, set its first byte's bit in the table, and also the
578 ph10 520 corresponding bit for the other version of a letter if we are caseless. In
579     UTF-8 mode, for characters greater than 127, we can only do the caseless thing
580     when Unicode property support is available.
581 nigel 77
582     Arguments:
583     start_bits points to the bit map
584 ph10 520 p points to the character
585 nigel 77 caseless the caseless flag
586     cd the block with char table pointers
587 chpe 1055 utf TRUE for UTF-8 / UTF-16 / UTF-32 mode
588 nigel 77
589 ph10 520 Returns: pointer after the character
590 nigel 77 */
591    
592 ph10 836 static const pcre_uchar *
593     set_table_bit(pcre_uint8 *start_bits, const pcre_uchar *p, BOOL caseless,
594     compile_data *cd, BOOL utf)
595 nigel 77 {
596 chpe 1102 pcre_uint32 c = *p;
597 ph10 520
598 ph10 836 #ifdef COMPILE_PCRE8
599 ph10 524 SET_BIT(c);
600    
601 ph10 836 #ifdef SUPPORT_UTF
602     if (utf && c > 127)
603 ph10 520 {
604     GETCHARINC(c, p);
605     #ifdef SUPPORT_UCP
606     if (caseless)
607     {
608 ph10 836 pcre_uchar buff[6];
609 ph10 520 c = UCD_OTHERCASE(c);
610 ph10 836 (void)PRIV(ord2utf)(c, buff);
611 ph10 535 SET_BIT(buff[0]);
612     }
613 ph10 1032 #endif /* Not SUPPORT_UCP */
614 ph10 520 return p;
615     }
616 ph10 1033 #else /* Not SUPPORT_UTF */
617 ph10 1221 (void)(utf); /* Stops warning for unused parameter */
618 ph10 1033 #endif /* SUPPORT_UTF */
619 ph10 520
620     /* Not UTF-8 mode, or character is less than 127. */
621    
622 ph10 524 if (caseless && (cd->ctypes[c] & ctype_letter) != 0) SET_BIT(cd->fcc[c]);
623 ph10 520 return p + 1;
624 ph10 1033 #endif /* COMPILE_PCRE8 */
625 ph10 836
626 chpe 1055 #if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
627 ph10 836 if (c > 0xff)
628     {
629     c = 0xff;
630     caseless = FALSE;
631     }
632     SET_BIT(c);
633    
634     #ifdef SUPPORT_UTF
635     if (utf && c > 127)
636     {
637     GETCHARINC(c, p);
638     #ifdef SUPPORT_UCP
639     if (caseless)
640     {
641     c = UCD_OTHERCASE(c);
642     if (c > 0xff)
643     c = 0xff;
644     SET_BIT(c);
645     }
646 ph10 1033 #endif /* SUPPORT_UCP */
647 ph10 836 return p;
648     }
649 ph10 1033 #else /* Not SUPPORT_UTF */
650 ph10 1221 (void)(utf); /* Stops warning for unused parameter */
651 ph10 1033 #endif /* SUPPORT_UTF */
652 ph10 836
653     if (caseless && (cd->ctypes[c] & ctype_letter) != 0) SET_BIT(cd->fcc[c]);
654     return p + 1;
655     #endif
656 nigel 77 }
657    
658    
659    
660     /*************************************************
661 ph10 539 * Set bits for a positive character type *
662     *************************************************/
663    
664     /* This function sets starting bits for a character type. In UTF-8 mode, we can
665     only do a direct setting for bytes less than 128, as otherwise there can be
666     confusion with bytes in the middle of UTF-8 characters. In a "traditional"
667     environment, the tables will only recognize ASCII characters anyway, but in at
668     least one Windows environment, some higher bytes bits were set in the tables.
669     So we deal with that case by considering the UTF-8 encoding.
670    
671     Arguments:
672     start_bits the starting bitmap
673     cbit type the type of character wanted
674     table_limit 32 for non-UTF-8; 16 for UTF-8
675 ph10 545 cd the block with char table pointers
676 ph10 539
677     Returns: nothing
678     */
679    
680     static void
681 chpe 1134 set_type_bits(pcre_uint8 *start_bits, int cbit_type, unsigned int table_limit,
682 ph10 539 compile_data *cd)
683     {
684 chpe 1095 register pcre_uint32 c;
685 ph10 539 for (c = 0; c < table_limit; c++) start_bits[c] |= cd->cbits[c+cbit_type];
686 ph10 836 #if defined SUPPORT_UTF && defined COMPILE_PCRE8
687 ph10 539 if (table_limit == 32) return;
688     for (c = 128; c < 256; c++)
689     {
690     if ((cd->cbits[c/8] & (1 << (c&7))) != 0)
691     {
692 ph10 836 pcre_uchar buff[6];
693     (void)PRIV(ord2utf)(c, buff);
694 ph10 545 SET_BIT(buff[0]);
695     }
696     }
697 ph10 836 #endif
698 ph10 539 }
699    
700    
701     /*************************************************
702     * Set bits for a negative character type *
703     *************************************************/
704    
705     /* This function sets starting bits for a negative character type such as \D.
706     In UTF-8 mode, we can only do a direct setting for bytes less than 128, as
707     otherwise there can be confusion with bytes in the middle of UTF-8 characters.
708 ph10 545 Unlike in the positive case, where we can set appropriate starting bits for
709 ph10 539 specific high-valued UTF-8 characters, in this case we have to set the bits for
710 ph10 545 all high-valued characters. The lowest is 0xc2, but we overkill by starting at
711 ph10 539 0xc0 (192) for simplicity.
712    
713     Arguments:
714     start_bits the starting bitmap
715     cbit type the type of character wanted
716     table_limit 32 for non-UTF-8; 16 for UTF-8
717 ph10 545 cd the block with char table pointers
718 ph10 539
719     Returns: nothing
720     */
721    
722     static void
723 chpe 1134 set_nottype_bits(pcre_uint8 *start_bits, int cbit_type, unsigned int table_limit,
724 ph10 539 compile_data *cd)
725     {
726 chpe 1095 register pcre_uint32 c;
727 ph10 539 for (c = 0; c < table_limit; c++) start_bits[c] |= ~cd->cbits[c+cbit_type];
728 ph10 836 #if defined SUPPORT_UTF && defined COMPILE_PCRE8
729 ph10 539 if (table_limit != 32) for (c = 24; c < 32; c++) start_bits[c] = 0xff;
730 ph10 836 #endif
731 ph10 539 }
732    
733    
734    
735     /*************************************************
736 nigel 93 * Create bitmap of starting bytes *
737 nigel 77 *************************************************/
738    
739 nigel 93 /* This function scans a compiled unanchored expression recursively and
740     attempts to build a bitmap of the set of possible starting bytes. As time goes
741     by, we may be able to get more clever at doing this. The SSB_CONTINUE return is
742     useful for parenthesized groups in patterns such as (a*)b where the group
743     provides some optional starting bytes but scanning must continue at the outer
744     level to find at least one mandatory byte. At the outermost level, this
745     function fails unless the result is SSB_DONE.
746 nigel 77
747     Arguments:
748     code points to an expression
749     start_bits points to a 32-byte table, initialized to 0
750 chpe 1055 utf TRUE if in UTF-8 / UTF-16 / UTF-32 mode
751 nigel 77 cd the block with char table pointers
752    
753 nigel 93 Returns: SSB_FAIL => Failed to find any starting bytes
754     SSB_DONE => Found mandatory starting bytes
755     SSB_CONTINUE => Found optional starting bytes
756 ph10 605 SSB_UNKNOWN => Hit an unrecognized opcode
757 nigel 77 */
758    
759 nigel 93 static int
760 ph10 836 set_start_bits(const pcre_uchar *code, pcre_uint8 *start_bits, BOOL utf,
761 ph10 603 compile_data *cd)
762 nigel 77 {
763 chpe 1095 register pcre_uint32 c;
764 nigel 93 int yield = SSB_DONE;
765 ph10 836 #if defined SUPPORT_UTF && defined COMPILE_PCRE8
766     int table_limit = utf? 16:32;
767     #else
768     int table_limit = 32;
769     #endif
770 nigel 77
771 nigel 91 #if 0
772     /* ========================================================================= */
773     /* The following comment and code was inserted in January 1999. In May 2006,
774     when it was observed to cause compiler warnings about unused values, I took it
775     out again. If anybody is still using OS/2, they will have to put it back
776     manually. */
777    
778 nigel 77 /* This next statement and the later reference to dummy are here in order to
779     trick the optimizer of the IBM C compiler for OS/2 into generating correct
780     code. Apparently IBM isn't going to fix the problem, and we would rather not
781     disable optimization (in this module it actually makes a big difference, and
782     the pcre module can use all the optimization it can get). */
783    
784     volatile int dummy;
785 nigel 91 /* ========================================================================= */
786     #endif
787 nigel 77
788     do
789     {
790     BOOL try_next = TRUE;
791 ph10 836 const pcre_uchar *tcode = code + 1 + LINK_SIZE;
792 ph10 605
793 ph10 604 if (*code == OP_CBRA || *code == OP_SCBRA ||
794 ph10 836 *code == OP_CBRAPOS || *code == OP_SCBRAPOS) tcode += IMM2_SIZE;
795 nigel 77
796 nigel 93 while (try_next) /* Loop for items in this branch */
797 nigel 77 {
798 nigel 93 int rc;
799 ph10 612
800 nigel 93 switch(*tcode)
801 nigel 77 {
802 ph10 605 /* If we reach something we don't understand, it means a new opcode has
803     been created that hasn't been added to this code. Hopefully this problem
804     will be discovered during testing. */
805 nigel 77
806     default:
807 ph10 605 return SSB_UNKNOWN;
808    
809     /* Fail for a valid opcode that implies no starting bits. */
810    
811     case OP_ACCEPT:
812 ph10 654 case OP_ASSERT_ACCEPT:
813 ph10 605 case OP_ALLANY:
814     case OP_ANY:
815     case OP_ANYBYTE:
816     case OP_CIRC:
817 ph10 654 case OP_CIRCM:
818 ph10 605 case OP_CLOSE:
819     case OP_COMMIT:
820     case OP_COND:
821 ph10 654 case OP_CREF:
822 ph10 605 case OP_DEF:
823 ph10 1365 case OP_DNCREF:
824     case OP_DNREF:
825     case OP_DNREFI:
826     case OP_DNRREF:
827 ph10 605 case OP_DOLL:
828 ph10 654 case OP_DOLLM:
829 ph10 605 case OP_END:
830     case OP_EOD:
831 ph10 654 case OP_EODN:
832 ph10 605 case OP_EXTUNI:
833     case OP_FAIL:
834     case OP_MARK:
835     case OP_NOT:
836     case OP_NOTEXACT:
837     case OP_NOTEXACTI:
838 ph10 654 case OP_NOTI:
839 ph10 605 case OP_NOTMINPLUS:
840     case OP_NOTMINPLUSI:
841     case OP_NOTMINQUERY:
842     case OP_NOTMINQUERYI:
843     case OP_NOTMINSTAR:
844     case OP_NOTMINSTARI:
845     case OP_NOTMINUPTO:
846     case OP_NOTMINUPTOI:
847     case OP_NOTPLUS:
848     case OP_NOTPLUSI:
849     case OP_NOTPOSPLUS:
850     case OP_NOTPOSPLUSI:
851     case OP_NOTPOSQUERY:
852     case OP_NOTPOSQUERYI:
853     case OP_NOTPOSSTAR:
854     case OP_NOTPOSSTARI:
855     case OP_NOTPOSUPTO:
856     case OP_NOTPOSUPTOI:
857     case OP_NOTPROP:
858     case OP_NOTQUERY:
859     case OP_NOTQUERYI:
860     case OP_NOTSTAR:
861     case OP_NOTSTARI:
862     case OP_NOTUPTO:
863     case OP_NOTUPTOI:
864     case OP_NOT_HSPACE:
865     case OP_NOT_VSPACE:
866     case OP_PROP:
867     case OP_PRUNE:
868     case OP_PRUNE_ARG:
869     case OP_RECURSE:
870     case OP_REF:
871     case OP_REFI:
872     case OP_REVERSE:
873     case OP_RREF:
874 ph10 654 case OP_SCOND:
875 ph10 605 case OP_SET_SOM:
876     case OP_SKIP:
877     case OP_SKIP_ARG:
878     case OP_SOD:
879     case OP_SOM:
880     case OP_THEN:
881     case OP_THEN_ARG:
882 nigel 93 return SSB_FAIL;
883 nigel 77
884 ph10 657 /* We can ignore word boundary tests. */
885 ph10 659
886 ph10 657 case OP_WORD_BOUNDARY:
887     case OP_NOT_WORD_BOUNDARY:
888 ph10 659 tcode++;
889     break;
890 ph10 657
891 nigel 93 /* If we hit a bracket or a positive lookahead assertion, recurse to set
892     bits from within the subpattern. If it can't find anything, we have to
893     give up. If it finds some mandatory character(s), we are done for this
894     branch. Otherwise, carry on scanning after the subpattern. */
895    
896     case OP_BRA:
897     case OP_SBRA:
898     case OP_CBRA:
899     case OP_SCBRA:
900 ph10 604 case OP_BRAPOS:
901     case OP_SBRAPOS:
902     case OP_CBRAPOS:
903     case OP_SCBRAPOS:
904 nigel 93 case OP_ONCE:
905 ph10 723 case OP_ONCE_NC:
906 nigel 93 case OP_ASSERT:
907 ph10 836 rc = set_start_bits(tcode, start_bits, utf, cd);
908 ph10 605 if (rc == SSB_FAIL || rc == SSB_UNKNOWN) return rc;
909 nigel 93 if (rc == SSB_DONE) try_next = FALSE; else
910     {
911     do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
912     tcode += 1 + LINK_SIZE;
913     }
914     break;
915    
916     /* If we hit ALT or KET, it means we haven't found anything mandatory in
917     this branch, though we might have found something optional. For ALT, we
918     continue with the next alternative, but we have to arrange that the final
919     result from subpattern is SSB_CONTINUE rather than SSB_DONE. For KET,
920     return SSB_CONTINUE: if this is the top level, that indicates failure,
921     but after a nested subpattern, it causes scanning to continue. */
922    
923     case OP_ALT:
924     yield = SSB_CONTINUE;
925     try_next = FALSE;
926     break;
927    
928     case OP_KET:
929     case OP_KETRMAX:
930     case OP_KETRMIN:
931 ph10 605 case OP_KETRPOS:
932 nigel 93 return SSB_CONTINUE;
933    
934 nigel 77 /* Skip over callout */
935    
936     case OP_CALLOUT:
937     tcode += 2 + 2*LINK_SIZE;
938     break;
939    
940     /* Skip over lookbehind and negative lookahead assertions */
941    
942     case OP_ASSERT_NOT:
943     case OP_ASSERTBACK:
944     case OP_ASSERTBACK_NOT:
945     do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
946 nigel 93 tcode += 1 + LINK_SIZE;
947 nigel 77 break;
948    
949     /* BRAZERO does the bracket, but carries on. */
950    
951     case OP_BRAZERO:
952     case OP_BRAMINZERO:
953 ph10 604 case OP_BRAPOSZERO:
954 ph10 836 rc = set_start_bits(++tcode, start_bits, utf, cd);
955 ph10 605 if (rc == SSB_FAIL || rc == SSB_UNKNOWN) return rc;
956 nigel 91 /* =========================================================================
957     See the comment at the head of this function concerning the next line,
958     which was an old fudge for the benefit of OS/2.
959 nigel 77 dummy = 1;
960 nigel 91 ========================================================================= */
961 nigel 77 do tcode += GET(tcode,1); while (*tcode == OP_ALT);
962 nigel 93 tcode += 1 + LINK_SIZE;
963 nigel 77 break;
964    
965 ph10 335 /* SKIPZERO skips the bracket. */
966    
967     case OP_SKIPZERO:
968 ph10 358 tcode++;
969 ph10 335 do tcode += GET(tcode,1); while (*tcode == OP_ALT);
970     tcode += 1 + LINK_SIZE;
971     break;
972    
973 nigel 77 /* Single-char * or ? sets the bit and tries the next item */
974    
975     case OP_STAR:
976     case OP_MINSTAR:
977 nigel 93 case OP_POSSTAR:
978 nigel 77 case OP_QUERY:
979     case OP_MINQUERY:
980 nigel 93 case OP_POSQUERY:
981 ph10 836 tcode = set_table_bit(start_bits, tcode + 1, FALSE, cd, utf);
982 nigel 77 break;
983    
984 ph10 602 case OP_STARI:
985     case OP_MINSTARI:
986     case OP_POSSTARI:
987     case OP_QUERYI:
988     case OP_MINQUERYI:
989     case OP_POSQUERYI:
990 ph10 836 tcode = set_table_bit(start_bits, tcode + 1, TRUE, cd, utf);
991 ph10 602 break;
992    
993 nigel 77 /* Single-char upto sets the bit and tries the next */
994    
995     case OP_UPTO:
996     case OP_MINUPTO:
997 nigel 93 case OP_POSUPTO:
998 ph10 836 tcode = set_table_bit(start_bits, tcode + 1 + IMM2_SIZE, FALSE, cd, utf);
999 nigel 77 break;
1000    
1001 ph10 602 case OP_UPTOI:
1002     case OP_MINUPTOI:
1003     case OP_POSUPTOI:
1004 ph10 836 tcode = set_table_bit(start_bits, tcode + 1 + IMM2_SIZE, TRUE, cd, utf);
1005 ph10 602 break;
1006    
1007 nigel 77 /* At least one single char sets the bit and stops */
1008    
1009 ph10 602 case OP_EXACT:
1010 ph10 836 tcode += IMM2_SIZE;
1011 ph10 602 /* Fall through */
1012 nigel 77 case OP_CHAR:
1013     case OP_PLUS:
1014     case OP_MINPLUS:
1015 nigel 93 case OP_POSPLUS:
1016 ph10 836 (void)set_table_bit(start_bits, tcode + 1, FALSE, cd, utf);
1017 nigel 77 try_next = FALSE;
1018     break;
1019 ph10 535
1020 ph10 603 case OP_EXACTI:
1021 ph10 836 tcode += IMM2_SIZE;
1022 ph10 603 /* Fall through */
1023 ph10 602 case OP_CHARI:
1024     case OP_PLUSI:
1025     case OP_MINPLUSI:
1026     case OP_POSPLUSI:
1027 ph10 836 (void)set_table_bit(start_bits, tcode + 1, TRUE, cd, utf);
1028 ph10 602 try_next = FALSE;
1029     break;
1030    
1031 ph10 535 /* Special spacing and line-terminating items. These recognize specific
1032     lists of characters. The difference between VSPACE and ANYNL is that the
1033     latter can match the two-character CRLF sequence, but that is not
1034     relevant for finding the first character, so their code here is
1035 ph10 524 identical. */
1036 ph10 535
1037 ph10 524 case OP_HSPACE:
1038 ph10 1033 SET_BIT(CHAR_HT);
1039     SET_BIT(CHAR_SPACE);
1040 ph10 836 #ifdef SUPPORT_UTF
1041     if (utf)
1042 ph10 535 {
1043 ph10 836 #ifdef COMPILE_PCRE8
1044 ph10 545 SET_BIT(0xC2); /* For U+00A0 */
1045 ph10 524 SET_BIT(0xE1); /* For U+1680, U+180E */
1046     SET_BIT(0xE2); /* For U+2000 - U+200A, U+202F, U+205F */
1047 ph10 535 SET_BIT(0xE3); /* For U+3000 */
1048 chpe 1055 #elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1049 ph10 836 SET_BIT(0xA0);
1050     SET_BIT(0xFF); /* For characters > 255 */
1051 chpe 1055 #endif /* COMPILE_PCRE[8|16|32] */
1052 ph10 524 }
1053 ph10 836 else
1054     #endif /* SUPPORT_UTF */
1055     {
1056 ph10 1221 #ifndef EBCDIC
1057 ph10 836 SET_BIT(0xA0);
1058 ph10 1221 #endif /* Not EBCDIC */
1059 chpe 1055 #if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1060 ph10 836 SET_BIT(0xFF); /* For characters > 255 */
1061 chpe 1055 #endif /* COMPILE_PCRE[16|32] */
1062 ph10 836 }
1063 ph10 524 try_next = FALSE;
1064 ph10 535 break;
1065 nigel 77
1066 ph10 535 case OP_ANYNL:
1067 ph10 524 case OP_VSPACE:
1068 ph10 1033 SET_BIT(CHAR_LF);
1069     SET_BIT(CHAR_VT);
1070     SET_BIT(CHAR_FF);
1071     SET_BIT(CHAR_CR);
1072 ph10 836 #ifdef SUPPORT_UTF
1073     if (utf)
1074 ph10 545 {
1075 ph10 836 #ifdef COMPILE_PCRE8
1076 ph10 545 SET_BIT(0xC2); /* For U+0085 */
1077 ph10 538 SET_BIT(0xE2); /* For U+2028, U+2029 */
1078 chpe 1055 #elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1079 ph10 1033 SET_BIT(CHAR_NEL);
1080 ph10 836 SET_BIT(0xFF); /* For characters > 255 */
1081 chpe 1055 #endif /* COMPILE_PCRE[8|16|32] */
1082 ph10 545 }
1083 ph10 836 else
1084     #endif /* SUPPORT_UTF */
1085     {
1086 ph10 1033 SET_BIT(CHAR_NEL);
1087 chpe 1055 #if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1088 ph10 836 SET_BIT(0xFF); /* For characters > 255 */
1089     #endif
1090     }
1091 ph10 524 try_next = FALSE;
1092 ph10 535 break;
1093 ph10 524
1094 ph10 535 /* Single character types set the bits and stop. Note that if PCRE_UCP
1095     is set, we do not see these op codes because \d etc are converted to
1096 ph10 545 properties. Therefore, these apply in the case when only characters less
1097 ph10 539 than 256 are recognized to match the types. */
1098 nigel 77
1099     case OP_NOT_DIGIT:
1100 ph10 539 set_nottype_bits(start_bits, cbit_digit, table_limit, cd);
1101 nigel 77 try_next = FALSE;
1102     break;
1103    
1104     case OP_DIGIT:
1105 ph10 539 set_type_bits(start_bits, cbit_digit, table_limit, cd);
1106 nigel 77 try_next = FALSE;
1107     break;
1108    
1109 nigel 91 /* The cbit_space table has vertical tab as whitespace; we have to
1110 ph10 1221 ensure it is set as not whitespace. Luckily, the code value is the same
1111 ph10 1033 (0x0b) in ASCII and EBCDIC, so we can just adjust the appropriate bit. */
1112 nigel 91
1113 nigel 77 case OP_NOT_WHITESPACE:
1114 ph10 539 set_nottype_bits(start_bits, cbit_space, table_limit, cd);
1115     start_bits[1] |= 0x08;
1116 nigel 77 try_next = FALSE;
1117     break;
1118    
1119 ph10 1033 /* The cbit_space table has vertical tab as whitespace; we have to not
1120     set it from the table. Luckily, the code value is the same (0x0b) in
1121     ASCII and EBCDIC, so we can just adjust the appropriate bit. */
1122 nigel 91
1123 nigel 77 case OP_WHITESPACE:
1124 ph10 539 c = start_bits[1]; /* Save in case it was already set */
1125     set_type_bits(start_bits, cbit_space, table_limit, cd);
1126     start_bits[1] = (start_bits[1] & ~0x08) | c;
1127 nigel 77 try_next = FALSE;
1128     break;
1129    
1130     case OP_NOT_WORDCHAR:
1131 ph10 539 set_nottype_bits(start_bits, cbit_word, table_limit, cd);
1132 nigel 77 try_next = FALSE;
1133     break;
1134    
1135     case OP_WORDCHAR:
1136 ph10 539 set_type_bits(start_bits, cbit_word, table_limit, cd);
1137 nigel 77 try_next = FALSE;
1138     break;
1139 ph10 545
1140 nigel 77 /* One or more character type fudges the pointer and restarts, knowing
1141     it will hit a single character type and stop there. */
1142    
1143     case OP_TYPEPLUS:
1144     case OP_TYPEMINPLUS:
1145 ph10 535 case OP_TYPEPOSPLUS:
1146 nigel 77 tcode++;
1147     break;
1148    
1149     case OP_TYPEEXACT:
1150 ph10 836 tcode += 1 + IMM2_SIZE;
1151 nigel 77 break;
1152    
1153     /* Zero or more repeats of character types set the bits and then
1154     try again. */
1155    
1156     case OP_TYPEUPTO:
1157     case OP_TYPEMINUPTO:
1158 nigel 93 case OP_TYPEPOSUPTO:
1159 ph10 836 tcode += IMM2_SIZE; /* Fall through */
1160 nigel 77
1161     case OP_TYPESTAR:
1162     case OP_TYPEMINSTAR:
1163 nigel 93 case OP_TYPEPOSSTAR:
1164 nigel 77 case OP_TYPEQUERY:
1165     case OP_TYPEMINQUERY:
1166 nigel 93 case OP_TYPEPOSQUERY:
1167 nigel 77 switch(tcode[1])
1168     {
1169 ph10 523 default:
1170 nigel 77 case OP_ANY:
1171 ph10 345 case OP_ALLANY:
1172 nigel 93 return SSB_FAIL;
1173 ph10 535
1174 ph10 524 case OP_HSPACE:
1175 ph10 1033 SET_BIT(CHAR_HT);
1176     SET_BIT(CHAR_SPACE);
1177 ph10 983 #ifdef SUPPORT_UTF
1178 ph10 836 if (utf)
1179 ph10 535 {
1180 ph10 836 #ifdef COMPILE_PCRE8
1181 ph10 545 SET_BIT(0xC2); /* For U+00A0 */
1182 ph10 524 SET_BIT(0xE1); /* For U+1680, U+180E */
1183     SET_BIT(0xE2); /* For U+2000 - U+200A, U+202F, U+205F */
1184 ph10 535 SET_BIT(0xE3); /* For U+3000 */
1185 chpe 1055 #elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1186 ph10 836 SET_BIT(0xA0);
1187     SET_BIT(0xFF); /* For characters > 255 */
1188 chpe 1055 #endif /* COMPILE_PCRE[8|16|32] */
1189 ph10 524 }
1190 ph10 836 else
1191     #endif /* SUPPORT_UTF */
1192 ph10 1033 #ifndef EBCDIC
1193 ph10 836 SET_BIT(0xA0);
1194 ph10 1221 #endif /* Not EBCDIC */
1195 ph10 535 break;
1196    
1197     case OP_ANYNL:
1198 ph10 524 case OP_VSPACE:
1199 ph10 1033 SET_BIT(CHAR_LF);
1200     SET_BIT(CHAR_VT);
1201     SET_BIT(CHAR_FF);
1202     SET_BIT(CHAR_CR);
1203 ph10 983 #ifdef SUPPORT_UTF
1204 ph10 836 if (utf)
1205 ph10 538 {
1206 ph10 836 #ifdef COMPILE_PCRE8
1207 ph10 545 SET_BIT(0xC2); /* For U+0085 */
1208 ph10 538 SET_BIT(0xE2); /* For U+2028, U+2029 */
1209 chpe 1055 #elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1210 ph10 1033 SET_BIT(CHAR_NEL);
1211 ph10 836 SET_BIT(0xFF); /* For characters > 255 */
1212 ph10 1033 #endif /* COMPILE_PCRE16 */
1213 ph10 545 }
1214 ph10 836 else
1215     #endif /* SUPPORT_UTF */
1216 ph10 1033 SET_BIT(CHAR_NEL);
1217 ph10 535 break;
1218    
1219 nigel 77 case OP_NOT_DIGIT:
1220 ph10 539 set_nottype_bits(start_bits, cbit_digit, table_limit, cd);
1221 nigel 77 break;
1222    
1223     case OP_DIGIT:
1224 ph10 539 set_type_bits(start_bits, cbit_digit, table_limit, cd);
1225 nigel 77 break;
1226    
1227 ph10 1404 /* The cbit_space table has vertical tab as whitespace; we no longer
1228     have to play fancy tricks because Perl added VT to its whitespace at
1229 ph10 1364 release 5.18. PCRE added it at release 8.34. */
1230 nigel 91
1231 nigel 77 case OP_NOT_WHITESPACE:
1232 ph10 539 set_nottype_bits(start_bits, cbit_space, table_limit, cd);
1233 nigel 77 break;
1234    
1235     case OP_WHITESPACE:
1236 ph10 539 set_type_bits(start_bits, cbit_space, table_limit, cd);
1237 nigel 77 break;
1238    
1239     case OP_NOT_WORDCHAR:
1240 ph10 539 set_nottype_bits(start_bits, cbit_word, table_limit, cd);
1241 nigel 77 break;
1242    
1243     case OP_WORDCHAR:
1244 ph10 539 set_type_bits(start_bits, cbit_word, table_limit, cd);
1245 nigel 77 break;
1246     }
1247    
1248     tcode += 2;
1249     break;
1250    
1251     /* Character class where all the information is in a bit map: set the
1252     bits and either carry on or not, according to the repeat count. If it was
1253     a negative class, and we are operating with UTF-8 characters, any byte
1254     with a value >= 0xc4 is a potentially valid starter because it starts a
1255     character with a value > 255. */
1256    
1257 zherczeg 1414 #if defined SUPPORT_UTF || !defined COMPILE_PCRE8
1258     case OP_XCLASS:
1259     if ((tcode[1 + LINK_SIZE] & XCL_HASPROP) != 0)
1260     return SSB_FAIL;
1261     /* All bits are set. */
1262     if ((tcode[1 + LINK_SIZE] & XCL_MAP) == 0 && (tcode[1 + LINK_SIZE] & XCL_NOT) != 0)
1263     return SSB_FAIL;
1264     #endif
1265     /* Fall through */
1266    
1267 nigel 77 case OP_NCLASS:
1268 ph10 836 #if defined SUPPORT_UTF && defined COMPILE_PCRE8
1269     if (utf)
1270 nigel 77 {
1271     start_bits[24] |= 0xf0; /* Bits for 0xc4 - 0xc8 */
1272     memset(start_bits+25, 0xff, 7); /* Bits for 0xc9 - 0xff */
1273     }
1274 ph10 111 #endif
1275 chpe 1055 #if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
1276 ph10 836 SET_BIT(0xFF); /* For characters > 255 */
1277     #endif
1278 nigel 77 /* Fall through */
1279    
1280     case OP_CLASS:
1281     {
1282 ph10 836 pcre_uint8 *map;
1283 zherczeg 1414 #if defined SUPPORT_UTF || !defined COMPILE_PCRE8
1284     map = NULL;
1285     if (*tcode == OP_XCLASS)
1286     {
1287     if ((tcode[1 + LINK_SIZE] & XCL_MAP) != 0)
1288     map = (pcre_uint8 *)(tcode + 1 + LINK_SIZE + 1);
1289     tcode += GET(tcode, 1);
1290     }
1291     else
1292     #endif
1293     {
1294     tcode++;
1295     map = (pcre_uint8 *)tcode;
1296     tcode += 32 / sizeof(pcre_uchar);
1297     }
1298 nigel 77
1299     /* In UTF-8 mode, the bits in a bit map correspond to character
1300     values, not to byte values. However, the bit map we are constructing is
1301     for byte values. So we have to do a conversion for characters whose
1302     value is > 127. In fact, there are only two possible starting bytes for
1303     characters in the range 128 - 255. */
1304    
1305 zherczeg 1414 #if defined SUPPORT_UTF || !defined COMPILE_PCRE8
1306     if (map != NULL)
1307     #endif
1308     {
1309 ph10 836 #if defined SUPPORT_UTF && defined COMPILE_PCRE8
1310 zherczeg 1414 if (utf)
1311 nigel 77 {
1312 zherczeg 1414 for (c = 0; c < 16; c++) start_bits[c] |= map[c];
1313     for (c = 128; c < 256; c++)
1314 nigel 77 {
1315 zherczeg 1414 if ((map[c/8] && (1 << (c&7))) != 0)
1316     {
1317     int d = (c >> 6) | 0xc0; /* Set bit for this starter */
1318     start_bits[d/8] |= (1 << (d&7)); /* and then skip on to the */
1319     c = (c & 0xc0) + 0x40 - 1; /* next relevant character. */
1320     }
1321 nigel 77 }
1322     }
1323 zherczeg 1414 else
1324 ph10 111 #endif
1325 zherczeg 1414 {
1326     /* In non-UTF-8 mode, the two bit maps are completely compatible. */
1327     for (c = 0; c < 32; c++) start_bits[c] |= map[c];
1328     }
1329 nigel 77 }
1330    
1331 ph10 654 /* Advance past the bit map, and act on what follows. For a zero
1332 ph10 605 minimum repeat, continue; otherwise stop processing. */
1333 nigel 77
1334     switch (*tcode)
1335     {
1336     case OP_CRSTAR:
1337     case OP_CRMINSTAR:
1338     case OP_CRQUERY:
1339     case OP_CRMINQUERY:
1340 ph10 1379 case OP_CRPOSSTAR:
1341     case OP_CRPOSQUERY:
1342 nigel 77 tcode++;
1343     break;
1344    
1345     case OP_CRRANGE:
1346     case OP_CRMINRANGE:
1347 ph10 1379 case OP_CRPOSRANGE:
1348 ph10 836 if (GET2(tcode, 1) == 0) tcode += 1 + 2 * IMM2_SIZE;
1349 nigel 77 else try_next = FALSE;
1350     break;
1351 ph10 654
1352 nigel 77 default:
1353     try_next = FALSE;
1354     break;
1355     }
1356     }
1357     break; /* End of bitmap class handling */
1358    
1359     } /* End of switch */
1360     } /* End of try_next loop */
1361    
1362     code += GET(code, 1); /* Advance to next branch */
1363     }
1364     while (*code == OP_ALT);
1365 nigel 93 return yield;
1366 nigel 77 }
1367    
1368    
1369    
1370 ph10 605
1371    
1372 nigel 77 /*************************************************
1373     * Study a compiled expression *
1374     *************************************************/
1375    
1376     /* This function is handed a compiled expression that it must study to produce
1377 zherczeg 850 information that will speed up the matching. It returns a pcre[16]_extra block
1378 nigel 77 which then gets handed back to pcre_exec().
1379    
1380     Arguments:
1381     re points to the compiled expression
1382     options contains option bits
1383     errorptr points to where to place error messages;
1384     set NULL unless error
1385    
1386 zherczeg 850 Returns: pointer to a pcre[16]_extra block, with study_data filled in and
1387     the appropriate flags set;
1388 nigel 77 NULL on error or if no optimization possible
1389     */
1390    
1391 chpe 1055 #if defined COMPILE_PCRE8
1392 ph10 359 PCRE_EXP_DEFN pcre_extra * PCRE_CALL_CONVENTION
1393 nigel 77 pcre_study(const pcre *external_re, int options, const char **errorptr)
1394 chpe 1055 #elif defined COMPILE_PCRE16
1395 zherczeg 850 PCRE_EXP_DEFN pcre16_extra * PCRE_CALL_CONVENTION
1396 zherczeg 852 pcre16_study(const pcre16 *external_re, int options, const char **errorptr)
1397 chpe 1055 #elif defined COMPILE_PCRE32
1398     PCRE_EXP_DEFN pcre32_extra * PCRE_CALL_CONVENTION
1399     pcre32_study(const pcre32 *external_re, int options, const char **errorptr)
1400 ph10 836 #endif
1401 nigel 77 {
1402 ph10 455 int min;
1403     BOOL bits_set = FALSE;
1404 ph10 836 pcre_uint8 start_bits[32];
1405 zherczeg 850 PUBL(extra) *extra = NULL;
1406 nigel 77 pcre_study_data *study;
1407 ph10 836 const pcre_uint8 *tables;
1408     pcre_uchar *code;
1409 nigel 91 compile_data compile_block;
1410 zherczeg 852 const REAL_PCRE *re = (const REAL_PCRE *)external_re;
1411 nigel 77
1412 ph10 1361
1413 nigel 77 *errorptr = NULL;
1414    
1415     if (re == NULL || re->magic_number != MAGIC_NUMBER)
1416     {
1417     *errorptr = "argument is not a compiled regular expression";
1418     return NULL;
1419     }
1420    
1421 ph10 836 if ((re->flags & PCRE_MODE) == 0)
1422     {
1423 chpe 1055 #if defined COMPILE_PCRE8
1424     *errorptr = "argument not compiled in 8 bit mode";
1425     #elif defined COMPILE_PCRE16
1426     *errorptr = "argument not compiled in 16 bit mode";
1427     #elif defined COMPILE_PCRE32
1428     *errorptr = "argument not compiled in 32 bit mode";
1429 ph10 836 #endif
1430     return NULL;
1431     }
1432    
1433 nigel 77 if ((options & ~PUBLIC_STUDY_OPTIONS) != 0)
1434     {
1435     *errorptr = "unknown or incorrect option bit(s) set";
1436     return NULL;
1437     }
1438    
1439 ph10 836 code = (pcre_uchar *)re + re->name_table_offset +
1440 nigel 91 (re->name_count * re->name_entry_size);
1441    
1442 nigel 77 /* For an anchored pattern, or an unanchored pattern that has a first char, or
1443 ph10 461 a multiline pattern that matches only at "line starts", there is no point in
1444 ph10 455 seeking a list of starting bytes. */
1445 nigel 77
1446 ph10 455 if ((re->options & PCRE_ANCHORED) == 0 &&
1447     (re->flags & (PCRE_FIRSTSET|PCRE_STARTLINE)) == 0)
1448     {
1449 ph10 605 int rc;
1450    
1451 ph10 455 /* Set the character tables in the block that is passed around */
1452 ph10 461
1453 ph10 455 tables = re->tables;
1454 ph10 836
1455 chpe 1055 #if defined COMPILE_PCRE8
1456 ph10 455 if (tables == NULL)
1457     (void)pcre_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
1458     (void *)(&tables));
1459 chpe 1055 #elif defined COMPILE_PCRE16
1460 ph10 836 if (tables == NULL)
1461     (void)pcre16_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
1462     (void *)(&tables));
1463 chpe 1055 #elif defined COMPILE_PCRE32
1464     if (tables == NULL)
1465     (void)pcre32_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
1466     (void *)(&tables));
1467 ph10 836 #endif
1468 ph10 461
1469 ph10 455 compile_block.lcc = tables + lcc_offset;
1470     compile_block.fcc = tables + fcc_offset;
1471     compile_block.cbits = tables + cbits_offset;
1472     compile_block.ctypes = tables + ctypes_offset;
1473 ph10 461
1474 ph10 455 /* See if we can find a fixed set of initial characters for the pattern. */
1475 ph10 461
1476 ph10 836 memset(start_bits, 0, 32 * sizeof(pcre_uint8));
1477 ph10 605 rc = set_start_bits(code, start_bits, (re->options & PCRE_UTF8) != 0,
1478     &compile_block);
1479     bits_set = rc == SSB_DONE;
1480 ph10 691 if (rc == SSB_UNKNOWN)
1481 ph10 688 {
1482     *errorptr = "internal error: opcode not recognized";
1483     return NULL;
1484 ph10 691 }
1485 ph10 455 }
1486 ph10 461
1487 ph10 455 /* Find the minimum length of subject string. */
1488 nigel 77
1489 ph10 1361 switch(min = find_minlength(re, code, code, re->options, 0))
1490 ph10 603 {
1491 ph10 688 case -2: *errorptr = "internal error: missing capturing bracket"; return NULL;
1492     case -3: *errorptr = "internal error: opcode not recognized"; return NULL;
1493 ph10 603 default: break;
1494 ph10 605 }
1495 ph10 708
1496 ph10 688 /* If a set of starting bytes has been identified, or if the minimum length is
1497 ph10 1221 greater than zero, or if JIT optimization has been requested, or if
1498 ph10 1022 PCRE_STUDY_EXTRA_NEEDED is set, get a pcre[16]_extra block and a
1499     pcre_study_data block. The study data is put in the latter, which is pointed to
1500     by the former, which may also get additional data set later by the calling
1501     program. At the moment, the size of pcre_study_data is fixed. We nevertheless
1502     save it in a field for returning via the pcre_fullinfo() function so that if it
1503     becomes variable in the future, we don't have to change that code. */
1504 nigel 77
1505 ph10 1022 if (bits_set || min > 0 || (options & (
1506 ph10 688 #ifdef SUPPORT_JIT
1507 ph10 1022 PCRE_STUDY_JIT_COMPILE | PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE |
1508 ph10 1221 PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE |
1509 ph10 688 #endif
1510 ph10 1022 PCRE_STUDY_EXTRA_NEEDED)) != 0)
1511 nigel 77 {
1512 zherczeg 850 extra = (PUBL(extra) *)(PUBL(malloc))
1513     (sizeof(PUBL(extra)) + sizeof(pcre_study_data));
1514 ph10 688 if (extra == NULL)
1515     {
1516     *errorptr = "failed to get memory";
1517     return NULL;
1518     }
1519 ph10 691
1520 zherczeg 850 study = (pcre_study_data *)((char *)extra + sizeof(PUBL(extra)));
1521 ph10 688 extra->flags = PCRE_EXTRA_STUDY_DATA;
1522     extra->study_data = study;
1523 ph10 691
1524 ph10 688 study->size = sizeof(pcre_study_data);
1525     study->flags = 0;
1526 ph10 797
1527 ph10 836 /* Set the start bits always, to avoid unset memory errors if the
1528     study data is written to a file, but set the flag only if any of the bits
1529     are set, to save time looking when none are. */
1530    
1531 ph10 797 if (bits_set)
1532 ph10 688 {
1533     study->flags |= PCRE_STUDY_MAPPED;
1534     memcpy(study->start_bits, start_bits, sizeof(start_bits));
1535     }
1536 ph10 836 else memset(study->start_bits, 0, 32 * sizeof(pcre_uint8));
1537 ph10 691
1538 ph10 836 #ifdef PCRE_DEBUG
1539     if (bits_set)
1540     {
1541 zherczeg 905 pcre_uint8 *ptr = start_bits;
1542 ph10 836 int i;
1543    
1544     printf("Start bits:\n");
1545     for (i = 0; i < 32; i++)
1546     printf("%3d: %02x%s", i * 8, *ptr++, ((i + 1) & 0x7) != 0? " " : "\n");
1547     }
1548     #endif
1549    
1550 ph10 691 /* Always set the minlength value in the block, because the JIT compiler
1551     makes use of it. However, don't set the bit unless the length is greater than
1552     zero - the interpretive pcre_exec() and pcre_dfa_exec() needn't waste time
1553 ph10 697 checking the zero case. */
1554 ph10 691
1555 ph10 708 if (min > 0)
1556 ph10 697 {
1557     study->flags |= PCRE_STUDY_MINLEN;
1558     study->minlength = min;
1559     }
1560 ph10 708 else study->minlength = 0;
1561 ph10 691
1562 ph10 688 /* If JIT support was compiled and requested, attempt the JIT compilation.
1563     If no starting bytes were found, and the minimum length is zero, and JIT
1564 ph10 1221 compilation fails, abandon the extra block and return NULL, unless
1565 ph10 1022 PCRE_STUDY_EXTRA_NEEDED is set. */
1566 ph10 691
1567 ph10 666 #ifdef SUPPORT_JIT
1568 ph10 688 extra->executable_jit = NULL;
1569 zherczeg 914 if ((options & PCRE_STUDY_JIT_COMPILE) != 0)
1570     PRIV(jit_compile)(re, extra, JIT_COMPILE);
1571     if ((options & PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE) != 0)
1572     PRIV(jit_compile)(re, extra, JIT_PARTIAL_SOFT_COMPILE);
1573     if ((options & PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE) != 0)
1574     PRIV(jit_compile)(re, extra, JIT_PARTIAL_HARD_COMPILE);
1575    
1576 ph10 1022 if (study->flags == 0 && (extra->flags & PCRE_EXTRA_EXECUTABLE_JIT) == 0 &&
1577     (options & PCRE_STUDY_EXTRA_NEEDED) == 0)
1578 ph10 688 {
1579 chpe 1055 #if defined COMPILE_PCRE8
1580 ph10 688 pcre_free_study(extra);
1581 chpe 1055 #elif defined COMPILE_PCRE16
1582 ph10 836 pcre16_free_study(extra);
1583 chpe 1055 #elif defined COMPILE_PCRE32
1584     pcre32_free_study(extra);
1585 ph10 836 #endif
1586 ph10 688 extra = NULL;
1587 ph10 691 }
1588 ph10 666 #endif
1589 ph10 688 }
1590 ph10 666
1591 nigel 77 return extra;
1592     }
1593    
1594 ph10 666
1595     /*************************************************
1596     * Free the study data *
1597     *************************************************/
1598    
1599     /* This function frees the memory that was obtained by pcre_study().
1600    
1601 zherczeg 850 Argument: a pointer to the pcre[16]_extra block
1602 ph10 666 Returns: nothing
1603     */
1604    
1605 chpe 1055 #if defined COMPILE_PCRE8
1606 ph10 666 PCRE_EXP_DEFN void
1607     pcre_free_study(pcre_extra *extra)
1608 chpe 1055 #elif defined COMPILE_PCRE16
1609 ph10 836 PCRE_EXP_DEFN void
1610 zherczeg 850 pcre16_free_study(pcre16_extra *extra)
1611 chpe 1055 #elif defined COMPILE_PCRE32
1612     PCRE_EXP_DEFN void
1613     pcre32_free_study(pcre32_extra *extra)
1614 ph10 836 #endif
1615 ph10 666 {
1616 ph10 836 if (extra == NULL)
1617     return;
1618 ph10 666 #ifdef SUPPORT_JIT
1619 ph10 691 if ((extra->flags & PCRE_EXTRA_EXECUTABLE_JIT) != 0 &&
1620 ph10 666 extra->executable_jit != NULL)
1621 ph10 836 PRIV(jit_free)(extra->executable_jit);
1622 ph10 666 #endif
1623 ph10 836 PUBL(free)(extra);
1624 ph10 666 }
1625    
1626 nigel 77 /* End of pcre_study.c */

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