1/*-
2 * This code is derived from OpenBSD's libc/regex, original license follows:
3 *
4 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
5 * Copyright (c) 1992, 1993, 1994
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Henry Spencer.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)regcomp.c 8.5 (Berkeley) 3/20/94
36 */
37
38#include <sys/types.h>
39#include <stdint.h>
40#include <stdio.h>
41#include <string.h>
42#include <ctype.h>
43#include <limits.h>
44#include <stdlib.h>
45#include "regex_impl.h"
46
47#include "regutils.h"
48#include "regex2.h"
49
50#include "llvm/Config/config.h"
51#include "llvm/Support/Compiler.h"
52
53/* character-class table */
54static struct cclass {
55 const char *name;
56 const char *chars;
57 const char *multis;
58} cclasses[] = {
59 { "alnum", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
600123456789", ""} ,
61 { "alpha", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz",
62 ""} ,
63 { "blank", " \t", ""} ,
64 { "cntrl", "\007\b\t\n\v\f\r\1\2\3\4\5\6\16\17\20\21\22\23\24\
65\25\26\27\30\31\32\33\34\35\36\37\177", ""} ,
66 { "digit", "0123456789", ""} ,
67 { "graph", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
680123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
69 ""} ,
70 { "lower", "abcdefghijklmnopqrstuvwxyz",
71 ""} ,
72 { "print", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
730123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~ ",
74 ""} ,
75 { "punct", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
76 ""} ,
77 { "space", "\t\n\v\f\r ", ""} ,
78 { "upper", "ABCDEFGHIJKLMNOPQRSTUVWXYZ",
79 ""} ,
80 { "xdigit", "0123456789ABCDEFabcdef",
81 ""} ,
82 { NULL, 0, "" }
83};
84
85/* character-name table */
86static struct cname {
87 const char *name;
88 char code;
89} cnames[] = {
90 { "NUL", '\0' },
91 { "SOH", '\001' },
92 { "STX", '\002' },
93 { "ETX", '\003' },
94 { "EOT", '\004' },
95 { "ENQ", '\005' },
96 { "ACK", '\006' },
97 { "BEL", '\007' },
98 { "alert", '\007' },
99 { "BS", '\010' },
100 { "backspace", '\b' },
101 { "HT", '\011' },
102 { "tab", '\t' },
103 { "LF", '\012' },
104 { "newline", '\n' },
105 { "VT", '\013' },
106 { "vertical-tab", '\v' },
107 { "FF", '\014' },
108 { "form-feed", '\f' },
109 { "CR", '\015' },
110 { "carriage-return", '\r' },
111 { "SO", '\016' },
112 { "SI", '\017' },
113 { "DLE", '\020' },
114 { "DC1", '\021' },
115 { "DC2", '\022' },
116 { "DC3", '\023' },
117 { "DC4", '\024' },
118 { "NAK", '\025' },
119 { "SYN", '\026' },
120 { "ETB", '\027' },
121 { "CAN", '\030' },
122 { "EM", '\031' },
123 { "SUB", '\032' },
124 { "ESC", '\033' },
125 { "IS4", '\034' },
126 { "FS", '\034' },
127 { "IS3", '\035' },
128 { "GS", '\035' },
129 { "IS2", '\036' },
130 { "RS", '\036' },
131 { "IS1", '\037' },
132 { "US", '\037' },
133 { "space", ' ' },
134 { "exclamation-mark", '!' },
135 { "quotation-mark", '"' },
136 { "number-sign", '#' },
137 { "dollar-sign", '$' },
138 { "percent-sign", '%' },
139 { "ampersand", '&' },
140 { "apostrophe", '\'' },
141 { "left-parenthesis", '(' },
142 { "right-parenthesis", ')' },
143 { "asterisk", '*' },
144 { "plus-sign", '+' },
145 { "comma", ',' },
146 { "hyphen", '-' },
147 { "hyphen-minus", '-' },
148 { "period", '.' },
149 { "full-stop", '.' },
150 { "slash", '/' },
151 { "solidus", '/' },
152 { "zero", '0' },
153 { "one", '1' },
154 { "two", '2' },
155 { "three", '3' },
156 { "four", '4' },
157 { "five", '5' },
158 { "six", '6' },
159 { "seven", '7' },
160 { "eight", '8' },
161 { "nine", '9' },
162 { "colon", ':' },
163 { "semicolon", ';' },
164 { "less-than-sign", '<' },
165 { "equals-sign", '=' },
166 { "greater-than-sign", '>' },
167 { "question-mark", '?' },
168 { "commercial-at", '@' },
169 { "left-square-bracket", '[' },
170 { "backslash", '\\' },
171 { "reverse-solidus", '\\' },
172 { "right-square-bracket", ']' },
173 { "circumflex", '^' },
174 { "circumflex-accent", '^' },
175 { "underscore", '_' },
176 { "low-line", '_' },
177 { "grave-accent", '`' },
178 { "left-brace", '{' },
179 { "left-curly-bracket", '{' },
180 { "vertical-line", '|' },
181 { "right-brace", '}' },
182 { "right-curly-bracket", '}' },
183 { "tilde", '~' },
184 { "DEL", '\177' },
185 { NULL, 0 }
186};
187
188/*
189 * parse structure, passed up and down to avoid global variables and
190 * other clumsinesses
191 */
192struct parse {
193 const char *next; /* next character in RE */
194 const char *end; /* end of string (-> NUL normally) */
195 int error; /* has an error been seen? */
196 sop *strip; /* malloced strip */
197 sopno ssize; /* malloced strip size (allocated) */
198 sopno slen; /* malloced strip length (used) */
199 int ncsalloc; /* number of csets allocated */
200 struct re_guts *g;
201# define NPAREN 10 /* we need to remember () 1-9 for back refs */
202 sopno pbegin[NPAREN]; /* -> ( ([0] unused) */
203 sopno pend[NPAREN]; /* -> ) ([0] unused) */
204};
205
206static void p_ere(struct parse *, int);
207static void p_ere_exp(struct parse *);
208static void p_str(struct parse *);
209static void p_bre(struct parse *, int, int);
210static int p_simp_re(struct parse *, int);
211static int p_count(struct parse *);
212static void p_bracket(struct parse *);
213static void p_b_term(struct parse *, cset *);
214static void p_b_cclass(struct parse *, cset *);
215static void p_b_eclass(struct parse *, cset *);
216static char p_b_symbol(struct parse *);
217static char p_b_coll_elem(struct parse *, int);
218static char othercase(int);
219static void bothcases(struct parse *, int);
220static void ordinary(struct parse *, int);
221static void nonnewline(struct parse *);
222static void repeat(struct parse *, sopno, int, int);
223static int seterr(struct parse *, int);
224static cset *allocset(struct parse *);
225static void freeset(struct parse *, cset *);
226static int freezeset(struct parse *, cset *);
227static int firstch(struct parse *, cset *);
228static int nch(struct parse *, cset *);
229static void mcadd(struct parse *, cset *, const char *);
230static void mcinvert(struct parse *, cset *);
231static void mccase(struct parse *, cset *);
232static int isinsets(struct re_guts *, int);
233static int samesets(struct re_guts *, int, int);
234static void categorize(struct parse *, struct re_guts *);
235static sopno dupl(struct parse *, sopno, sopno);
236static void doemit(struct parse *, sop, size_t);
237static void doinsert(struct parse *, sop, size_t, sopno);
238static void dofwd(struct parse *, sopno, sop);
239static void enlarge(struct parse *, sopno);
240static void stripsnug(struct parse *, struct re_guts *);
241static void findmust(struct parse *, struct re_guts *);
242static sopno pluscount(struct parse *, struct re_guts *);
243
244static char nuls[10]; /* place to point scanner in event of error */
245
246/*
247 * macros for use with parse structure
248 * BEWARE: these know that the parse structure is named `p' !!!
249 */
250#define PEEK() (*p->next)
251#define PEEK2() (*(p->next+1))
252#define MORE() (p->end - p->next > 0)
253#define MORE2() (p->end - p->next > 1)
254#define SEE(c) (MORE() && PEEK() == (c))
255#define SEETWO(a, b) (MORE2() && PEEK() == (a) && PEEK2() == (b))
256#define EAT(c) ((SEE(c)) ? (NEXT(), 1) : 0)
257#define EATTWO(a, b) ((SEETWO(a, b)) ? (NEXT2(), 1) : 0)
258#define NEXT() (p->next++)
259#define NEXT2() (p->next += 2)
260#define NEXTn(n) (p->next += (n))
261#define GETNEXT() (*p->next++)
262#define SETERROR(e) seterr(p, (e))
263#define REQUIRE(co, e) (void)((co) || SETERROR(e))
264#define MUSTSEE(c, e) (REQUIRE(MORE() && PEEK() == (c), e))
265#define MUSTEAT(c, e) (REQUIRE(MORE() && GETNEXT() == (c), e))
266#define MUSTNOTSEE(c, e) (REQUIRE(!MORE() || PEEK() != (c), e))
267#define EMIT(op, sopnd) doemit(p, (sop)(op), (size_t)(sopnd))
268#define INSERT(op, pos) doinsert(p, (sop)(op), HERE()-(pos)+1, pos)
269#define AHEAD(pos) dofwd(p, pos, HERE()-(pos))
270#define ASTERN(sop, pos) EMIT(sop, HERE()-pos)
271#define HERE() (p->slen)
272#define THERE() (p->slen - 1)
273#define THERETHERE() (p->slen - 2)
274#define DROP(n) (p->slen -= (n))
275
276#ifdef _POSIX2_RE_DUP_MAX
277#define DUPMAX _POSIX2_RE_DUP_MAX
278#else
279#define DUPMAX 255
280#endif
281#define REGINFINITY (DUPMAX + 1)
282
283#ifndef NDEBUG
284static int never = 0; /* for use in asserts; shuts lint up */
285#else
286#define never 0 /* some <assert.h>s have bugs too */
287#endif
288
289/*
290 - llvm_regcomp - interface for parser and compilation
291 */
292int /* 0 success, otherwise REG_something */
293llvm_regcomp(llvm_regex_t *preg, const char *pattern, int cflags)
294{
295 struct parse pa;
296 struct re_guts *g;
297 struct parse *p = &pa;
298 int i;
299 size_t len;
300#ifdef REDEBUG
301# define GOODFLAGS(f) (f)
302#else
303# define GOODFLAGS(f) ((f)&~REG_DUMP)
304#endif
305
306 cflags = GOODFLAGS(cflags);
307 if ((cflags&REG_EXTENDED) && (cflags&REG_NOSPEC))
308 return(REG_INVARG);
309
310 if (cflags&REG_PEND) {
311 if (preg->re_endp < pattern)
312 return(REG_INVARG);
313 len = preg->re_endp - pattern;
314 } else
315 len = strlen(s: (const char *)pattern);
316
317 /* do the mallocs early so failure handling is easy */
318 g = (struct re_guts *)malloc(size: sizeof(struct re_guts) +
319 (NC-1)*sizeof(cat_t));
320 if (g == NULL)
321 return(REG_ESPACE);
322 p->ssize = len/(size_t)2*(size_t)3 + (size_t)1; /* ugh */
323 p->strip = (sop *)calloc(nmemb: p->ssize, size: sizeof(sop));
324 p->slen = 0;
325 if (p->strip == NULL) {
326 free(ptr: (char *)g);
327 return(REG_ESPACE);
328 }
329
330 /* set things up */
331 p->g = g;
332 p->next = pattern;
333 p->end = p->next + len;
334 p->error = 0;
335 p->ncsalloc = 0;
336 for (i = 0; i < NPAREN; i++) {
337 p->pbegin[i] = 0;
338 p->pend[i] = 0;
339 }
340 g->csetsize = NC;
341 g->sets = NULL;
342 g->setbits = NULL;
343 g->ncsets = 0;
344 g->cflags = cflags;
345 g->iflags = 0;
346 g->nbol = 0;
347 g->neol = 0;
348 g->must = NULL;
349 g->mlen = 0;
350 g->nsub = 0;
351 g->ncategories = 1; /* category 0 is "everything else" */
352 g->categories = &g->catspace[-(CHAR_MIN)];
353 (void) memset(s: (char *)g->catspace, c: 0, NC*sizeof(cat_t));
354 g->backrefs = 0;
355
356 /* do it */
357 EMIT(OEND, 0);
358 g->firststate = THERE();
359 if (cflags&REG_EXTENDED)
360 p_ere(p, OUT);
361 else if (cflags&REG_NOSPEC)
362 p_str(p);
363 else
364 p_bre(p, OUT, OUT);
365 EMIT(OEND, 0);
366 g->laststate = THERE();
367
368 /* tidy up loose ends and fill things in */
369 categorize(p, g);
370 stripsnug(p, g);
371 findmust(p, g);
372 g->nplus = pluscount(p, g);
373 g->magic = MAGIC2;
374 preg->re_nsub = g->nsub;
375 preg->re_g = g;
376 preg->re_magic = MAGIC1;
377#ifndef REDEBUG
378 /* not debugging, so can't rely on the assert() in llvm_regexec() */
379 if (g->iflags&REGEX_BAD)
380 SETERROR(REG_ASSERT);
381#endif
382
383 /* win or lose, we're done */
384 if (p->error != 0) /* lose */
385 llvm_regfree(preg);
386 return(p->error);
387}
388
389/*
390 - p_ere - ERE parser top level, concatenation and alternation
391 */
392static void
393p_ere(struct parse *p, int stop) /* character this ERE should end at */
394{
395 char c;
396 sopno prevback = 0;
397 sopno prevfwd = 0;
398 sopno conc;
399 int first = 1; /* is this the first alternative? */
400
401 for (;;) {
402 /* do a bunch of concatenated expressions */
403 conc = HERE();
404 while (MORE() && (c = PEEK()) != '|' && c != stop)
405 p_ere_exp(p);
406 REQUIRE(HERE() != conc, REG_EMPTY); /* require nonempty */
407
408 if (!EAT('|'))
409 break; /* NOTE BREAK OUT */
410
411 if (first) {
412 INSERT(OCH_, conc); /* offset is wrong */
413 prevfwd = conc;
414 prevback = conc;
415 first = 0;
416 }
417 ASTERN(OOR1, prevback);
418 prevback = THERE();
419 AHEAD(prevfwd); /* fix previous offset */
420 prevfwd = HERE();
421 EMIT(OOR2, 0); /* offset is very wrong */
422 }
423
424 if (!first) { /* tail-end fixups */
425 AHEAD(prevfwd);
426 ASTERN(O_CH, prevback);
427 }
428
429 assert(!MORE() || SEE(stop));
430}
431
432/*
433 - p_ere_exp - parse one subERE, an atom possibly followed by a repetition op
434 */
435static void
436p_ere_exp(struct parse *p)
437{
438 char c;
439 sopno pos;
440 int count;
441 int count2;
442 int backrefnum;
443 sopno subno;
444 int wascaret = 0;
445
446 assert(MORE()); /* caller should have ensured this */
447 c = GETNEXT();
448
449 pos = HERE();
450 switch (c) {
451 case '(':
452 REQUIRE(MORE(), REG_EPAREN);
453 p->g->nsub++;
454 subno = p->g->nsub;
455 if (subno < NPAREN)
456 p->pbegin[subno] = HERE();
457 EMIT(OLPAREN, subno);
458 if (!SEE(')'))
459 p_ere(p, stop: ')');
460 if (subno < NPAREN) {
461 p->pend[subno] = HERE();
462 assert(p->pend[subno] != 0);
463 }
464 EMIT(ORPAREN, subno);
465 MUSTEAT(')', REG_EPAREN);
466 break;
467#ifndef POSIX_MISTAKE
468 case ')': /* happens only if no current unmatched ( */
469 /*
470 * You may ask, why the ifndef? Because I didn't notice
471 * this until slightly too late for 1003.2, and none of the
472 * other 1003.2 regular-expression reviewers noticed it at
473 * all. So an unmatched ) is legal POSIX, at least until
474 * we can get it fixed.
475 */
476 SETERROR(REG_EPAREN);
477 break;
478#endif
479 case '^':
480 EMIT(OBOL, 0);
481 p->g->iflags |= USEBOL;
482 p->g->nbol++;
483 wascaret = 1;
484 break;
485 case '$':
486 EMIT(OEOL, 0);
487 p->g->iflags |= USEEOL;
488 p->g->neol++;
489 break;
490 case '|':
491 SETERROR(REG_EMPTY);
492 break;
493 case '*':
494 case '+':
495 case '?':
496 SETERROR(REG_BADRPT);
497 break;
498 case '.':
499 if (p->g->cflags&REG_NEWLINE)
500 nonnewline(p);
501 else
502 EMIT(OANY, 0);
503 break;
504 case '[':
505 p_bracket(p);
506 break;
507 case '\\':
508 REQUIRE(MORE(), REG_EESCAPE);
509 c = GETNEXT();
510 if (c >= '1' && c <= '9') {
511 /* \[0-9] is taken to be a back-reference to a previously specified
512 * matching group. backrefnum will hold the number. The matching
513 * group must exist (i.e. if \4 is found there must have been at
514 * least 4 matching groups specified in the pattern previously).
515 */
516 backrefnum = c - '0';
517 if (p->pend[backrefnum] == 0) {
518 SETERROR(REG_ESUBREG);
519 break;
520 }
521
522 /* Make sure everything checks out and emit the sequence
523 * that marks a back-reference to the parse structure.
524 */
525 assert(backrefnum <= p->g->nsub);
526 EMIT(OBACK_, backrefnum);
527 assert(p->pbegin[backrefnum] != 0);
528 assert(OP(p->strip[p->pbegin[backrefnum]]) == OLPAREN);
529 assert(OP(p->strip[p->pend[backrefnum]]) == ORPAREN);
530 (void) dupl(p, p->pbegin[backrefnum]+1, p->pend[backrefnum]);
531 EMIT(O_BACK, backrefnum);
532 p->g->backrefs = 1;
533 } else {
534 /* Other chars are simply themselves when escaped with a backslash.
535 */
536 ordinary(p, c);
537 }
538 break;
539 case '{': /* okay as ordinary except if digit follows */
540 REQUIRE(!MORE() || !isdigit((uch)PEEK()), REG_BADRPT);
541 LLVM_FALLTHROUGH;
542 default:
543 ordinary(p, c);
544 break;
545 }
546
547 if (!MORE())
548 return;
549 c = PEEK();
550 /* we call { a repetition if followed by a digit */
551 if (!( c == '*' || c == '+' || c == '?' ||
552 (c == '{' && MORE2() && isdigit((uch)PEEK2())) ))
553 return; /* no repetition, we're done */
554 NEXT();
555
556 REQUIRE(!wascaret, REG_BADRPT);
557 switch (c) {
558 case '*': /* implemented as +? */
559 /* this case does not require the (y|) trick, noKLUDGE */
560 INSERT(OPLUS_, pos);
561 ASTERN(O_PLUS, pos);
562 INSERT(OQUEST_, pos);
563 ASTERN(O_QUEST, pos);
564 break;
565 case '+':
566 INSERT(OPLUS_, pos);
567 ASTERN(O_PLUS, pos);
568 break;
569 case '?':
570 /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
571 INSERT(OCH_, pos); /* offset slightly wrong */
572 ASTERN(OOR1, pos); /* this one's right */
573 AHEAD(pos); /* fix the OCH_ */
574 EMIT(OOR2, 0); /* offset very wrong... */
575 AHEAD(THERE()); /* ...so fix it */
576 ASTERN(O_CH, THERETHERE());
577 break;
578 case '{':
579 count = p_count(p);
580 if (EAT(',')) {
581 if (isdigit((uch)PEEK())) {
582 count2 = p_count(p);
583 REQUIRE(count <= count2, REG_BADBR);
584 } else /* single number with comma */
585 count2 = REGINFINITY;
586 } else /* just a single number */
587 count2 = count;
588 repeat(p, pos, count, count2);
589 if (!EAT('}')) { /* error heuristics */
590 while (MORE() && PEEK() != '}')
591 NEXT();
592 REQUIRE(MORE(), REG_EBRACE);
593 SETERROR(REG_BADBR);
594 }
595 break;
596 }
597
598 if (!MORE())
599 return;
600 c = PEEK();
601 if (!( c == '*' || c == '+' || c == '?' ||
602 (c == '{' && MORE2() && isdigit((uch)PEEK2())) ) )
603 return;
604 SETERROR(REG_BADRPT);
605}
606
607/*
608 - p_str - string (no metacharacters) "parser"
609 */
610static void
611p_str(struct parse *p)
612{
613 REQUIRE(MORE(), REG_EMPTY);
614 while (MORE())
615 ordinary(p, GETNEXT());
616}
617
618/*
619 - p_bre - BRE parser top level, anchoring and concatenation
620 * Giving end1 as OUT essentially eliminates the end1/end2 check.
621 *
622 * This implementation is a bit of a kludge, in that a trailing $ is first
623 * taken as an ordinary character and then revised to be an anchor. The
624 * only undesirable side effect is that '$' gets included as a character
625 * category in such cases. This is fairly harmless; not worth fixing.
626 * The amount of lookahead needed to avoid this kludge is excessive.
627 */
628static void
629p_bre(struct parse *p,
630 int end1, /* first terminating character */
631 int end2) /* second terminating character */
632{
633 sopno start = HERE();
634 int first = 1; /* first subexpression? */
635 int wasdollar = 0;
636
637 if (EAT('^')) {
638 EMIT(OBOL, 0);
639 p->g->iflags |= USEBOL;
640 p->g->nbol++;
641 }
642 while (MORE() && !SEETWO(end1, end2)) {
643 wasdollar = p_simp_re(p, first);
644 first = 0;
645 }
646 if (wasdollar) { /* oops, that was a trailing anchor */
647 DROP(1);
648 EMIT(OEOL, 0);
649 p->g->iflags |= USEEOL;
650 p->g->neol++;
651 }
652
653 REQUIRE(HERE() != start, REG_EMPTY); /* require nonempty */
654}
655
656/*
657 - p_simp_re - parse a simple RE, an atom possibly followed by a repetition
658 */
659static int /* was the simple RE an unbackslashed $? */
660p_simp_re(struct parse *p,
661 int starordinary) /* is a leading * an ordinary character? */
662{
663 int c;
664 int count;
665 int count2;
666 sopno pos;
667 int i;
668 sopno subno;
669# define BACKSL (1<<CHAR_BIT)
670
671 pos = HERE(); /* repetition op, if any, covers from here */
672
673 assert(MORE()); /* caller should have ensured this */
674 c = GETNEXT();
675 if (c == '\\') {
676 REQUIRE(MORE(), REG_EESCAPE);
677 c = BACKSL | GETNEXT();
678 }
679 switch (c) {
680 case '.':
681 if (p->g->cflags&REG_NEWLINE)
682 nonnewline(p);
683 else
684 EMIT(OANY, 0);
685 break;
686 case '[':
687 p_bracket(p);
688 break;
689 case BACKSL|'{':
690 SETERROR(REG_BADRPT);
691 break;
692 case BACKSL|'(':
693 p->g->nsub++;
694 subno = p->g->nsub;
695 if (subno < NPAREN)
696 p->pbegin[subno] = HERE();
697 EMIT(OLPAREN, subno);
698 /* the MORE here is an error heuristic */
699 if (MORE() && !SEETWO('\\', ')'))
700 p_bre(p, end1: '\\', end2: ')');
701 if (subno < NPAREN) {
702 p->pend[subno] = HERE();
703 assert(p->pend[subno] != 0);
704 }
705 EMIT(ORPAREN, subno);
706 REQUIRE(EATTWO('\\', ')'), REG_EPAREN);
707 break;
708 case BACKSL|')': /* should not get here -- must be user */
709 case BACKSL|'}':
710 SETERROR(REG_EPAREN);
711 break;
712 case BACKSL|'1':
713 case BACKSL|'2':
714 case BACKSL|'3':
715 case BACKSL|'4':
716 case BACKSL|'5':
717 case BACKSL|'6':
718 case BACKSL|'7':
719 case BACKSL|'8':
720 case BACKSL|'9':
721 i = (c&~BACKSL) - '0';
722 assert(i < NPAREN);
723 if (p->pend[i] != 0) {
724 assert(i <= p->g->nsub);
725 EMIT(OBACK_, i);
726 assert(p->pbegin[i] != 0);
727 assert(OP(p->strip[p->pbegin[i]]) == OLPAREN);
728 assert(OP(p->strip[p->pend[i]]) == ORPAREN);
729 (void) dupl(p, p->pbegin[i]+1, p->pend[i]);
730 EMIT(O_BACK, i);
731 } else
732 SETERROR(REG_ESUBREG);
733 p->g->backrefs = 1;
734 break;
735 case '*':
736 REQUIRE(starordinary, REG_BADRPT);
737 LLVM_FALLTHROUGH;
738 default:
739 ordinary(p, (char)c);
740 break;
741 }
742
743 if (EAT('*')) { /* implemented as +? */
744 /* this case does not require the (y|) trick, noKLUDGE */
745 INSERT(OPLUS_, pos);
746 ASTERN(O_PLUS, pos);
747 INSERT(OQUEST_, pos);
748 ASTERN(O_QUEST, pos);
749 } else if (EATTWO('\\', '{')) {
750 count = p_count(p);
751 if (EAT(',')) {
752 if (MORE() && isdigit((uch)PEEK())) {
753 count2 = p_count(p);
754 REQUIRE(count <= count2, REG_BADBR);
755 } else /* single number with comma */
756 count2 = REGINFINITY;
757 } else /* just a single number */
758 count2 = count;
759 repeat(p, pos, count, count2);
760 if (!EATTWO('\\', '}')) { /* error heuristics */
761 while (MORE() && !SEETWO('\\', '}'))
762 NEXT();
763 REQUIRE(MORE(), REG_EBRACE);
764 SETERROR(REG_BADBR);
765 }
766 } else if (c == '$') /* $ (but not \$) ends it */
767 return(1);
768
769 return(0);
770}
771
772/*
773 - p_count - parse a repetition count
774 */
775static int /* the value */
776p_count(struct parse *p)
777{
778 int count = 0;
779 int ndigits = 0;
780
781 while (MORE() && isdigit((uch)PEEK()) && count <= DUPMAX) {
782 count = count*10 + (GETNEXT() - '0');
783 ndigits++;
784 }
785
786 REQUIRE(ndigits > 0 && count <= DUPMAX, REG_BADBR);
787 return(count);
788}
789
790/*
791 - p_bracket - parse a bracketed character list
792 *
793 * Note a significant property of this code: if the allocset() did SETERROR,
794 * no set operations are done.
795 */
796static void
797p_bracket(struct parse *p)
798{
799 cset *cs;
800 int invert = 0;
801
802 /* Dept of Truly Sickening Special-Case Kludges */
803 if (p->end - p->next > 5) {
804 if (strncmp(s1: p->next, s2: "[:<:]]", n: 6) == 0) {
805 EMIT(OBOW, 0);
806 NEXTn(6);
807 return;
808 }
809 if (strncmp(s1: p->next, s2: "[:>:]]", n: 6) == 0) {
810 EMIT(OEOW, 0);
811 NEXTn(6);
812 return;
813 }
814 }
815
816 if ((cs = allocset(p)) == NULL) {
817 /* allocset did set error status in p */
818 return;
819 }
820
821 if (EAT('^'))
822 invert++; /* make note to invert set at end */
823 if (EAT(']'))
824 CHadd(cs, ']');
825 else if (EAT('-'))
826 CHadd(cs, '-');
827 while (MORE() && PEEK() != ']' && !SEETWO('-', ']'))
828 p_b_term(p, cs);
829 if (EAT('-'))
830 CHadd(cs, '-');
831 MUSTEAT(']', REG_EBRACK);
832
833 if (p->error != 0) { /* don't mess things up further */
834 freeset(p, cs);
835 return;
836 }
837
838 if (p->g->cflags&REG_ICASE) {
839 int i;
840 int ci;
841
842 for (i = p->g->csetsize - 1; i >= 0; i--)
843 if (CHIN(cs, i) && isalpha(i)) {
844 ci = othercase(i);
845 if (ci != i)
846 CHadd(cs, ci);
847 }
848 if (cs->multis != NULL)
849 mccase(p, cs);
850 }
851 if (invert) {
852 int i;
853
854 for (i = p->g->csetsize - 1; i >= 0; i--)
855 if (CHIN(cs, i))
856 CHsub(cs, i);
857 else
858 CHadd(cs, i);
859 if (p->g->cflags&REG_NEWLINE)
860 CHsub(cs, '\n');
861 if (cs->multis != NULL)
862 mcinvert(p, cs);
863 }
864
865 assert(cs->multis == NULL); /* xxx */
866
867 if (nch(p, cs) == 1) { /* optimize singleton sets */
868 ordinary(p, firstch(p, cs));
869 freeset(p, cs);
870 } else
871 EMIT(OANYOF, freezeset(p, cs));
872}
873
874/*
875 - p_b_term - parse one term of a bracketed character list
876 */
877static void
878p_b_term(struct parse *p, cset *cs)
879{
880 char c;
881 char start, finish;
882 int i;
883
884 /* classify what we've got */
885 switch ((MORE()) ? PEEK() : '\0') {
886 case '[':
887 c = (MORE2()) ? PEEK2() : '\0';
888 break;
889 case '-':
890 SETERROR(REG_ERANGE);
891 return; /* NOTE RETURN */
892 break;
893 default:
894 c = '\0';
895 break;
896 }
897
898 switch (c) {
899 case ':': /* character class */
900 NEXT2();
901 REQUIRE(MORE(), REG_EBRACK);
902 c = PEEK();
903 REQUIRE(c != '-' && c != ']', REG_ECTYPE);
904 p_b_cclass(p, cs);
905 REQUIRE(MORE(), REG_EBRACK);
906 REQUIRE(EATTWO(':', ']'), REG_ECTYPE);
907 break;
908 case '=': /* equivalence class */
909 NEXT2();
910 REQUIRE(MORE(), REG_EBRACK);
911 c = PEEK();
912 REQUIRE(c != '-' && c != ']', REG_ECOLLATE);
913 p_b_eclass(p, cs);
914 REQUIRE(MORE(), REG_EBRACK);
915 REQUIRE(EATTWO('=', ']'), REG_ECOLLATE);
916 break;
917 default: /* symbol, ordinary character, or range */
918/* xxx revision needed for multichar stuff */
919 start = p_b_symbol(p);
920 if (SEE('-') && MORE2() && PEEK2() != ']') {
921 /* range */
922 NEXT();
923 if (EAT('-'))
924 finish = '-';
925 else
926 finish = p_b_symbol(p);
927 } else
928 finish = start;
929/* xxx what about signed chars here... */
930 REQUIRE(start <= finish, REG_ERANGE);
931 for (i = start; i <= finish; i++)
932 CHadd(cs, i);
933 break;
934 }
935}
936
937/*
938 - p_b_cclass - parse a character-class name and deal with it
939 */
940static void
941p_b_cclass(struct parse *p, cset *cs)
942{
943 const char *sp = p->next;
944 struct cclass *cp;
945 size_t len;
946 const char *u;
947 char c;
948
949 while (MORE() && isalpha((uch)PEEK()))
950 NEXT();
951 len = p->next - sp;
952 for (cp = cclasses; cp->name != NULL; cp++)
953 if (strncmp(s1: cp->name, s2: sp, n: len) == 0 && cp->name[len] == '\0')
954 break;
955 if (cp->name == NULL) {
956 /* oops, didn't find it */
957 SETERROR(REG_ECTYPE);
958 return;
959 }
960
961 u = cp->chars;
962 while ((c = *u++) != '\0')
963 CHadd(cs, c);
964 for (u = cp->multis; *u != '\0'; u += strlen(s: u) + 1)
965 MCadd(p, cs, u);
966}
967
968/*
969 - p_b_eclass - parse an equivalence-class name and deal with it
970 *
971 * This implementation is incomplete. xxx
972 */
973static void
974p_b_eclass(struct parse *p, cset *cs)
975{
976 char c;
977
978 c = p_b_coll_elem(p, '=');
979 CHadd(cs, c);
980}
981
982/*
983 - p_b_symbol - parse a character or [..]ed multicharacter collating symbol
984 */
985static char /* value of symbol */
986p_b_symbol(struct parse *p)
987{
988 char value;
989
990 REQUIRE(MORE(), REG_EBRACK);
991 if (!EATTWO('[', '.'))
992 return(GETNEXT());
993
994 /* collating symbol */
995 value = p_b_coll_elem(p, '.');
996 REQUIRE(EATTWO('.', ']'), REG_ECOLLATE);
997 return(value);
998}
999
1000/*
1001 - p_b_coll_elem - parse a collating-element name and look it up
1002 */
1003static char /* value of collating element */
1004p_b_coll_elem(struct parse *p,
1005 int endc) /* name ended by endc,']' */
1006{
1007 const char *sp = p->next;
1008 struct cname *cp;
1009 size_t len;
1010
1011 while (MORE() && !SEETWO(endc, ']'))
1012 NEXT();
1013 if (!MORE()) {
1014 SETERROR(REG_EBRACK);
1015 return(0);
1016 }
1017 len = p->next - sp;
1018 for (cp = cnames; cp->name != NULL; cp++)
1019 if (strncmp(s1: cp->name, s2: sp, n: len) == 0 && strlen(s: cp->name) == len)
1020 return(cp->code); /* known name */
1021 if (len == 1)
1022 return(*sp); /* single character */
1023 SETERROR(REG_ECOLLATE); /* neither */
1024 return(0);
1025}
1026
1027/*
1028 - othercase - return the case counterpart of an alphabetic
1029 */
1030static char /* if no counterpart, return ch */
1031othercase(int ch)
1032{
1033 ch = (uch)ch;
1034 assert(isalpha(ch));
1035 if (isupper(ch))
1036 return ((uch)tolower(ch));
1037 else if (islower(ch))
1038 return ((uch)toupper(ch));
1039 else /* peculiar, but could happen */
1040 return(ch);
1041}
1042
1043/*
1044 - bothcases - emit a dualcase version of a two-case character
1045 *
1046 * Boy, is this implementation ever a kludge...
1047 */
1048static void
1049bothcases(struct parse *p, int ch)
1050{
1051 const char *oldnext = p->next;
1052 const char *oldend = p->end;
1053 char bracket[3];
1054
1055 ch = (uch)ch;
1056 assert(othercase(ch) != ch); /* p_bracket() would recurse */
1057 p->next = bracket;
1058 p->end = bracket+2;
1059 bracket[0] = ch;
1060 bracket[1] = ']';
1061 bracket[2] = '\0';
1062 p_bracket(p);
1063 assert(p->next == bracket+2);
1064 p->next = oldnext;
1065 p->end = oldend;
1066}
1067
1068/*
1069 - ordinary - emit an ordinary character
1070 */
1071static void
1072ordinary(struct parse *p, int ch)
1073{
1074 cat_t *cap = p->g->categories;
1075
1076 if ((p->g->cflags&REG_ICASE) && isalpha((uch)ch) && othercase(ch) != ch)
1077 bothcases(p, ch);
1078 else {
1079 EMIT(OCHAR, (uch)ch);
1080 if (cap[ch] == 0)
1081 cap[ch] = p->g->ncategories++;
1082 }
1083}
1084
1085/*
1086 - nonnewline - emit REG_NEWLINE version of OANY
1087 *
1088 * Boy, is this implementation ever a kludge...
1089 */
1090static void
1091nonnewline(struct parse *p)
1092{
1093 const char *oldnext = p->next;
1094 const char *oldend = p->end;
1095 static const char bracket[4] = {'^', '\n', ']', '\0'};
1096
1097 p->next = bracket;
1098 p->end = bracket+3;
1099 p_bracket(p);
1100 assert(p->next == bracket+3);
1101 p->next = oldnext;
1102 p->end = oldend;
1103}
1104
1105/*
1106 - repeat - generate code for a bounded repetition, recursively if needed
1107 */
1108static void
1109repeat(struct parse *p,
1110 sopno start, /* operand from here to end of strip */
1111 int from, /* repeated from this number */
1112 int to) /* to this number of times (maybe INFINITY) */
1113{
1114 sopno finish = HERE();
1115# define N 2
1116# define INF 3
1117# define REP(f, t) ((f)*8 + (t))
1118# define MAP(n) (((n) <= 1) ? (n) : ((n) == REGINFINITY) ? INF : N)
1119 sopno copy;
1120
1121 if (p->error != 0) /* head off possible runaway recursion */
1122 return;
1123
1124 assert(from <= to);
1125
1126 switch (REP(MAP(from), MAP(to))) {
1127 case REP(0, 0): /* must be user doing this */
1128 DROP(finish-start); /* drop the operand */
1129 break;
1130 case REP(0, 1): /* as x{1,1}? */
1131 case REP(0, N): /* as x{1,n}? */
1132 case REP(0, INF): /* as x{1,}? */
1133 /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
1134 INSERT(OCH_, start); /* offset is wrong... */
1135 repeat(p, start: start+1, from: 1, to);
1136 ASTERN(OOR1, start);
1137 AHEAD(start); /* ... fix it */
1138 EMIT(OOR2, 0);
1139 AHEAD(THERE());
1140 ASTERN(O_CH, THERETHERE());
1141 break;
1142 case REP(1, 1): /* trivial case */
1143 /* done */
1144 break;
1145 case REP(1, N): /* as x?x{1,n-1} */
1146 /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
1147 INSERT(OCH_, start);
1148 ASTERN(OOR1, start);
1149 AHEAD(start);
1150 EMIT(OOR2, 0); /* offset very wrong... */
1151 AHEAD(THERE()); /* ...so fix it */
1152 ASTERN(O_CH, THERETHERE());
1153 copy = dupl(p, start+1, finish+1);
1154 assert(copy == finish+4);
1155 repeat(p, start: copy, from: 1, to: to-1);
1156 break;
1157 case REP(1, INF): /* as x+ */
1158 INSERT(OPLUS_, start);
1159 ASTERN(O_PLUS, start);
1160 break;
1161 case REP(N, N): /* as xx{m-1,n-1} */
1162 copy = dupl(p, start, finish);
1163 repeat(p, start: copy, from: from-1, to: to-1);
1164 break;
1165 case REP(N, INF): /* as xx{n-1,INF} */
1166 copy = dupl(p, start, finish);
1167 repeat(p, start: copy, from: from-1, to);
1168 break;
1169 default: /* "can't happen" */
1170 SETERROR(REG_ASSERT); /* just in case */
1171 break;
1172 }
1173}
1174
1175/*
1176 - seterr - set an error condition
1177 */
1178static int /* useless but makes type checking happy */
1179seterr(struct parse *p, int e)
1180{
1181 if (p->error == 0) /* keep earliest error condition */
1182 p->error = e;
1183 p->next = nuls; /* try to bring things to a halt */
1184 p->end = nuls;
1185 return(0); /* make the return value well-defined */
1186}
1187
1188/*
1189 - allocset - allocate a set of characters for []
1190 */
1191static cset *
1192allocset(struct parse *p)
1193{
1194 int no = p->g->ncsets++;
1195 size_t nc;
1196 size_t nbytes;
1197 cset *cs;
1198 size_t css = (size_t)p->g->csetsize;
1199 int i;
1200
1201 if (no >= p->ncsalloc) { /* need another column of space */
1202 void *ptr;
1203
1204 p->ncsalloc += CHAR_BIT;
1205 nc = p->ncsalloc;
1206 if (nc > SIZE_MAX / sizeof(cset))
1207 goto nomem;
1208 assert(nc % CHAR_BIT == 0);
1209 nbytes = nc / CHAR_BIT * css;
1210
1211 ptr = (cset *)realloc(ptr: (char *)p->g->sets, size: nc * sizeof(cset));
1212 if (ptr == NULL)
1213 goto nomem;
1214 p->g->sets = ptr;
1215
1216 ptr = (uch *)realloc(ptr: (char *)p->g->setbits, size: nbytes);
1217 if (ptr == NULL)
1218 goto nomem;
1219 p->g->setbits = ptr;
1220
1221 for (i = 0; i < no; i++)
1222 p->g->sets[i].ptr = p->g->setbits + css*(i/CHAR_BIT);
1223
1224 (void) memset(s: (char *)p->g->setbits + (nbytes - css), c: 0, n: css);
1225 }
1226 /* XXX should not happen */
1227 if (p->g->sets == NULL || p->g->setbits == NULL)
1228 goto nomem;
1229
1230 cs = &p->g->sets[no];
1231 cs->ptr = p->g->setbits + css*((no)/CHAR_BIT);
1232 cs->mask = 1 << ((no) % CHAR_BIT);
1233 cs->hash = 0;
1234 cs->smultis = 0;
1235 cs->multis = NULL;
1236
1237 return(cs);
1238nomem:
1239 free(ptr: p->g->sets);
1240 p->g->sets = NULL;
1241 free(ptr: p->g->setbits);
1242 p->g->setbits = NULL;
1243
1244 SETERROR(REG_ESPACE);
1245 /* caller's responsibility not to do set ops */
1246 return(NULL);
1247}
1248
1249/*
1250 - freeset - free a now-unused set
1251 */
1252static void
1253freeset(struct parse *p, cset *cs)
1254{
1255 size_t i;
1256 cset *top = &p->g->sets[p->g->ncsets];
1257 size_t css = (size_t)p->g->csetsize;
1258
1259 for (i = 0; i < css; i++)
1260 CHsub(cs, i);
1261 if (cs == top-1) /* recover only the easy case */
1262 p->g->ncsets--;
1263}
1264
1265/*
1266 - freezeset - final processing on a set of characters
1267 *
1268 * The main task here is merging identical sets. This is usually a waste
1269 * of time (although the hash code minimizes the overhead), but can win
1270 * big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash
1271 * is done using addition rather than xor -- all ASCII [aA] sets xor to
1272 * the same value!
1273 */
1274static int /* set number */
1275freezeset(struct parse *p, cset *cs)
1276{
1277 uch h = cs->hash;
1278 size_t i;
1279 cset *top = &p->g->sets[p->g->ncsets];
1280 cset *cs2;
1281 size_t css = (size_t)p->g->csetsize;
1282
1283 /* look for an earlier one which is the same */
1284 for (cs2 = &p->g->sets[0]; cs2 < top; cs2++)
1285 if (cs2->hash == h && cs2 != cs) {
1286 /* maybe */
1287 for (i = 0; i < css; i++)
1288 if (!!CHIN(cs2, i) != !!CHIN(cs, i))
1289 break; /* no */
1290 if (i == css)
1291 break; /* yes */
1292 }
1293
1294 if (cs2 < top) { /* found one */
1295 freeset(p, cs);
1296 cs = cs2;
1297 }
1298
1299 return((int)(cs - p->g->sets));
1300}
1301
1302/*
1303 - firstch - return first character in a set (which must have at least one)
1304 */
1305static int /* character; there is no "none" value */
1306firstch(struct parse *p, cset *cs)
1307{
1308 size_t i;
1309 size_t css = (size_t)p->g->csetsize;
1310
1311 for (i = 0; i < css; i++)
1312 if (CHIN(cs, i))
1313 return((char)i);
1314 assert(never);
1315 return(0); /* arbitrary */
1316}
1317
1318/*
1319 - nch - number of characters in a set
1320 */
1321static int
1322nch(struct parse *p, cset *cs)
1323{
1324 size_t i;
1325 size_t css = (size_t)p->g->csetsize;
1326 int n = 0;
1327
1328 for (i = 0; i < css; i++)
1329 if (CHIN(cs, i))
1330 n++;
1331 return(n);
1332}
1333
1334/*
1335 - mcadd - add a collating element to a cset
1336 */
1337static void
1338mcadd( struct parse *p, cset *cs, const char *cp)
1339{
1340 size_t oldend = cs->smultis;
1341 void *np;
1342
1343 cs->smultis += strlen(s: cp) + 1;
1344 np = realloc(ptr: cs->multis, size: cs->smultis);
1345 if (np == NULL) {
1346 if (cs->multis)
1347 free(ptr: cs->multis);
1348 cs->multis = NULL;
1349 SETERROR(REG_ESPACE);
1350 return;
1351 }
1352 cs->multis = np;
1353
1354 llvm_strlcpy(dst: cs->multis + oldend - 1, src: cp, siz: cs->smultis - oldend + 1);
1355}
1356
1357/*
1358 - mcinvert - invert the list of collating elements in a cset
1359 *
1360 * This would have to know the set of possibilities. Implementation
1361 * is deferred.
1362 */
1363/* ARGSUSED */
1364static void
1365mcinvert(struct parse *p, cset *cs)
1366{
1367 assert(cs->multis == NULL); /* xxx */
1368}
1369
1370/*
1371 - mccase - add case counterparts of the list of collating elements in a cset
1372 *
1373 * This would have to know the set of possibilities. Implementation
1374 * is deferred.
1375 */
1376/* ARGSUSED */
1377static void
1378mccase(struct parse *p, cset *cs)
1379{
1380 assert(cs->multis == NULL); /* xxx */
1381}
1382
1383/*
1384 - isinsets - is this character in any sets?
1385 */
1386static int /* predicate */
1387isinsets(struct re_guts *g, int c)
1388{
1389 uch *col;
1390 int i;
1391 int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT;
1392 unsigned uc = (uch)c;
1393
1394 for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize)
1395 if (col[uc] != 0)
1396 return(1);
1397 return(0);
1398}
1399
1400/*
1401 - samesets - are these two characters in exactly the same sets?
1402 */
1403static int /* predicate */
1404samesets(struct re_guts *g, int c1, int c2)
1405{
1406 uch *col;
1407 int i;
1408 int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT;
1409 unsigned uc1 = (uch)c1;
1410 unsigned uc2 = (uch)c2;
1411
1412 for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize)
1413 if (col[uc1] != col[uc2])
1414 return(0);
1415 return(1);
1416}
1417
1418/*
1419 - categorize - sort out character categories
1420 */
1421static void
1422categorize(struct parse *p, struct re_guts *g)
1423{
1424 cat_t *cats = g->categories;
1425 int c;
1426 int c2;
1427 cat_t cat;
1428
1429 /* avoid making error situations worse */
1430 if (p->error != 0)
1431 return;
1432
1433 for (c = CHAR_MIN; c <= CHAR_MAX; c++)
1434 if (cats[c] == 0 && isinsets(g, c)) {
1435 cat = g->ncategories++;
1436 cats[c] = cat;
1437 for (c2 = c+1; c2 <= CHAR_MAX; c2++)
1438 if (cats[c2] == 0 && samesets(g, c1: c, c2))
1439 cats[c2] = cat;
1440 }
1441}
1442
1443/*
1444 - dupl - emit a duplicate of a bunch of sops
1445 */
1446static sopno /* start of duplicate */
1447dupl(struct parse *p,
1448 sopno start, /* from here */
1449 sopno finish) /* to this less one */
1450{
1451 sopno ret = HERE();
1452 sopno len = finish - start;
1453
1454 assert(finish >= start);
1455 if (len == 0)
1456 return(ret);
1457 enlarge(p, p->ssize + len); /* this many unexpected additions */
1458 assert(p->ssize >= p->slen + len);
1459 (void) memmove(dest: (char *)(p->strip + p->slen),
1460 src: (char *)(p->strip + start), n: (size_t)len*sizeof(sop));
1461 p->slen += len;
1462 return(ret);
1463}
1464
1465/*
1466 - doemit - emit a strip operator
1467 *
1468 * It might seem better to implement this as a macro with a function as
1469 * hard-case backup, but it's just too big and messy unless there are
1470 * some changes to the data structures. Maybe later.
1471 */
1472static void
1473doemit(struct parse *p, sop op, size_t opnd)
1474{
1475 /* avoid making error situations worse */
1476 if (p->error != 0)
1477 return;
1478
1479 /* deal with oversize operands ("can't happen", more or less) */
1480 assert(opnd < 1<<OPSHIFT);
1481
1482 /* deal with undersized strip */
1483 if (p->slen >= p->ssize)
1484 enlarge(p, (p->ssize+1) / 2 * 3); /* +50% */
1485 assert(p->slen < p->ssize);
1486
1487 /* finally, it's all reduced to the easy case */
1488 p->strip[p->slen++] = SOP(op, opnd);
1489}
1490
1491/*
1492 - doinsert - insert a sop into the strip
1493 */
1494static void
1495doinsert(struct parse *p, sop op, size_t opnd, sopno pos)
1496{
1497 sopno sn;
1498 sop s;
1499 int i;
1500
1501 /* avoid making error situations worse */
1502 if (p->error != 0)
1503 return;
1504
1505 sn = HERE();
1506 EMIT(op, opnd); /* do checks, ensure space */
1507 assert(HERE() == sn+1);
1508 s = p->strip[sn];
1509
1510 /* adjust paren pointers */
1511 assert(pos > 0);
1512 for (i = 1; i < NPAREN; i++) {
1513 if (p->pbegin[i] >= pos) {
1514 p->pbegin[i]++;
1515 }
1516 if (p->pend[i] >= pos) {
1517 p->pend[i]++;
1518 }
1519 }
1520
1521 memmove(dest: (char *)&p->strip[pos+1], src: (char *)&p->strip[pos],
1522 n: (HERE()-pos-1)*sizeof(sop));
1523 p->strip[pos] = s;
1524}
1525
1526/*
1527 - dofwd - complete a forward reference
1528 */
1529static void
1530dofwd(struct parse *p, sopno pos, sop value)
1531{
1532 /* avoid making error situations worse */
1533 if (p->error != 0)
1534 return;
1535
1536 assert(value < 1<<OPSHIFT);
1537 p->strip[pos] = OP(p->strip[pos]) | value;
1538}
1539
1540/*
1541 - enlarge - enlarge the strip
1542 */
1543static void
1544enlarge(struct parse *p, sopno size)
1545{
1546 sop *sp;
1547
1548 if (p->ssize >= size)
1549 return;
1550
1551 if ((uintptr_t)size > SIZE_MAX / sizeof(sop)) {
1552 SETERROR(REG_ESPACE);
1553 return;
1554 }
1555
1556 sp = (sop *)realloc(ptr: p->strip, size: size*sizeof(sop));
1557 if (sp == NULL) {
1558 SETERROR(REG_ESPACE);
1559 return;
1560 }
1561 p->strip = sp;
1562 p->ssize = size;
1563}
1564
1565/*
1566 - stripsnug - compact the strip
1567 */
1568static void
1569stripsnug(struct parse *p, struct re_guts *g)
1570{
1571 g->nstates = p->slen;
1572 if ((uintptr_t)p->slen > SIZE_MAX / sizeof(sop)) {
1573 g->strip = p->strip;
1574 SETERROR(REG_ESPACE);
1575 return;
1576 }
1577
1578 g->strip = (sop *)realloc(ptr: (char *)p->strip, size: p->slen * sizeof(sop));
1579 if (g->strip == NULL) {
1580 SETERROR(REG_ESPACE);
1581 g->strip = p->strip;
1582 }
1583}
1584
1585/*
1586 - findmust - fill in must and mlen with longest mandatory literal string
1587 *
1588 * This algorithm could do fancy things like analyzing the operands of |
1589 * for common subsequences. Someday. This code is simple and finds most
1590 * of the interesting cases.
1591 *
1592 * Note that must and mlen got initialized during setup.
1593 */
1594static void
1595findmust(struct parse *p, struct re_guts *g)
1596{
1597 sop *scan;
1598 sop *start = 0; /* start initialized in the default case, after that */
1599 sop *newstart = 0; /* newstart was initialized in the OCHAR case */
1600 sopno newlen;
1601 sop s;
1602 char *cp;
1603 sopno i;
1604
1605 /* avoid making error situations worse */
1606 if (p->error != 0)
1607 return;
1608
1609 /* find the longest OCHAR sequence in strip */
1610 newlen = 0;
1611 scan = g->strip + 1;
1612 do {
1613 s = *scan++;
1614 switch (OP(s)) {
1615 case OCHAR: /* sequence member */
1616 if (newlen == 0) /* new sequence */
1617 newstart = scan - 1;
1618 newlen++;
1619 break;
1620 case OPLUS_: /* things that don't break one */
1621 case OLPAREN:
1622 case ORPAREN:
1623 break;
1624 case OQUEST_: /* things that must be skipped */
1625 case OCH_:
1626 scan--;
1627 do {
1628 scan += OPND(s);
1629 s = *scan;
1630 /* assert() interferes w debug printouts */
1631 if (OP(s) != O_QUEST && OP(s) != O_CH &&
1632 OP(s) != OOR2) {
1633 g->iflags |= REGEX_BAD;
1634 return;
1635 }
1636 } while (OP(s) != O_QUEST && OP(s) != O_CH);
1637 LLVM_FALLTHROUGH;
1638 default: /* things that break a sequence */
1639 if (newlen > g->mlen) { /* ends one */
1640 start = newstart;
1641 g->mlen = newlen;
1642 }
1643 newlen = 0;
1644 break;
1645 }
1646 } while (OP(s) != OEND);
1647
1648 if (g->mlen == 0) /* there isn't one */
1649 return;
1650
1651 /* turn it into a character string */
1652 g->must = malloc(size: (size_t)g->mlen + 1);
1653 if (g->must == NULL) { /* argh; just forget it */
1654 g->mlen = 0;
1655 return;
1656 }
1657 cp = g->must;
1658 scan = start;
1659 for (i = g->mlen; i > 0; i--) {
1660 while (OP(s = *scan++) != OCHAR)
1661 continue;
1662 assert(cp < g->must + g->mlen);
1663 *cp++ = (char)OPND(s);
1664 }
1665 assert(cp == g->must + g->mlen);
1666 *cp++ = '\0'; /* just on general principles */
1667}
1668
1669/*
1670 - pluscount - count + nesting
1671 */
1672static sopno /* nesting depth */
1673pluscount(struct parse *p, struct re_guts *g)
1674{
1675 sop *scan;
1676 sop s;
1677 sopno plusnest = 0;
1678 sopno maxnest = 0;
1679
1680 if (p->error != 0)
1681 return(0); /* there may not be an OEND */
1682
1683 scan = g->strip + 1;
1684 do {
1685 s = *scan++;
1686 switch (OP(s)) {
1687 case OPLUS_:
1688 plusnest++;
1689 break;
1690 case O_PLUS:
1691 if (plusnest > maxnest)
1692 maxnest = plusnest;
1693 plusnest--;
1694 break;
1695 }
1696 } while (OP(s) != OEND);
1697 if (plusnest != 0)
1698 g->iflags |= REGEX_BAD;
1699 return(maxnest);
1700}
1701