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Diffstat (limited to 'gnu/llvm/lib/Support/regcomp.c')
| -rw-r--r-- | gnu/llvm/lib/Support/regcomp.c | 1701 |
1 files changed, 0 insertions, 1701 deletions
diff --git a/gnu/llvm/lib/Support/regcomp.c b/gnu/llvm/lib/Support/regcomp.c deleted file mode 100644 index 12669ab75d1..00000000000 --- a/gnu/llvm/lib/Support/regcomp.c +++ /dev/null @@ -1,1701 +0,0 @@ -/*- - * This code is derived from OpenBSD's libc/regex, original license follows: - * - * Copyright (c) 1992, 1993, 1994 Henry Spencer. - * Copyright (c) 1992, 1993, 1994 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * Henry Spencer. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - * - * @(#)regcomp.c 8.5 (Berkeley) 3/20/94 - */ - -#include <sys/types.h> -#include <stdint.h> -#include <stdio.h> -#include <string.h> -#include <ctype.h> -#include <limits.h> -#include <stdlib.h> -#include "regex_impl.h" - -#include "regutils.h" -#include "regex2.h" - -#include "llvm/Config/config.h" - -/* character-class table */ -static struct cclass { - const char *name; - const char *chars; - const char *multis; -} cclasses[] = { - { "alnum", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\ -0123456789", ""} , - { "alpha", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", - ""} , - { "blank", " \t", ""} , - { "cntrl", "\007\b\t\n\v\f\r\1\2\3\4\5\6\16\17\20\21\22\23\24\ -\25\26\27\30\31\32\33\34\35\36\37\177", ""} , - { "digit", "0123456789", ""} , - { "graph", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\ -0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", - ""} , - { "lower", "abcdefghijklmnopqrstuvwxyz", - ""} , - { "print", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\ -0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~ ", - ""} , - { "punct", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", - ""} , - { "space", "\t\n\v\f\r ", ""} , - { "upper", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", - ""} , - { "xdigit", "0123456789ABCDEFabcdef", - ""} , - { NULL, 0, "" } -}; - -/* character-name table */ -static struct cname { - const char *name; - char code; -} cnames[] = { - { "NUL", '\0' }, - { "SOH", '\001' }, - { "STX", '\002' }, - { "ETX", '\003' }, - { "EOT", '\004' }, - { "ENQ", '\005' }, - { "ACK", '\006' }, - { "BEL", '\007' }, - { "alert", '\007' }, - { "BS", '\010' }, - { "backspace", '\b' }, - { "HT", '\011' }, - { "tab", '\t' }, - { "LF", '\012' }, - { "newline", '\n' }, - { "VT", '\013' }, - { "vertical-tab", '\v' }, - { "FF", '\014' }, - { "form-feed", '\f' }, - { "CR", '\015' }, - { "carriage-return", '\r' }, - { "SO", '\016' }, - { "SI", '\017' }, - { "DLE", '\020' }, - { "DC1", '\021' }, - { "DC2", '\022' }, - { "DC3", '\023' }, - { "DC4", '\024' }, - { "NAK", '\025' }, - { "SYN", '\026' }, - { "ETB", '\027' }, - { "CAN", '\030' }, - { "EM", '\031' }, - { "SUB", '\032' }, - { "ESC", '\033' }, - { "IS4", '\034' }, - { "FS", '\034' }, - { "IS3", '\035' }, - { "GS", '\035' }, - { "IS2", '\036' }, - { "RS", '\036' }, - { "IS1", '\037' }, - { "US", '\037' }, - { "space", ' ' }, - { "exclamation-mark", '!' }, - { "quotation-mark", '"' }, - { "number-sign", '#' }, - { "dollar-sign", '$' }, - { "percent-sign", '%' }, - { "ampersand", '&' }, - { "apostrophe", '\'' }, - { "left-parenthesis", '(' }, - { "right-parenthesis", ')' }, - { "asterisk", '*' }, - { "plus-sign", '+' }, - { "comma", ',' }, - { "hyphen", '-' }, - { "hyphen-minus", '-' }, - { "period", '.' }, - { "full-stop", '.' }, - { "slash", '/' }, - { "solidus", '/' }, - { "zero", '0' }, - { "one", '1' }, - { "two", '2' }, - { "three", '3' }, - { "four", '4' }, - { "five", '5' }, - { "six", '6' }, - { "seven", '7' }, - { "eight", '8' }, - { "nine", '9' }, - { "colon", ':' }, - { "semicolon", ';' }, - { "less-than-sign", '<' }, - { "equals-sign", '=' }, - { "greater-than-sign", '>' }, - { "question-mark", '?' }, - { "commercial-at", '@' }, - { "left-square-bracket", '[' }, - { "backslash", '\\' }, - { "reverse-solidus", '\\' }, - { "right-square-bracket", ']' }, - { "circumflex", '^' }, - { "circumflex-accent", '^' }, - { "underscore", '_' }, - { "low-line", '_' }, - { "grave-accent", '`' }, - { "left-brace", '{' }, - { "left-curly-bracket", '{' }, - { "vertical-line", '|' }, - { "right-brace", '}' }, - { "right-curly-bracket", '}' }, - { "tilde", '~' }, - { "DEL", '\177' }, - { NULL, 0 } -}; - -/* - * parse structure, passed up and down to avoid global variables and - * other clumsinesses - */ -struct parse { - char *next; /* next character in RE */ - char *end; /* end of string (-> NUL normally) */ - int error; /* has an error been seen? */ - sop *strip; /* malloced strip */ - sopno ssize; /* malloced strip size (allocated) */ - sopno slen; /* malloced strip length (used) */ - int ncsalloc; /* number of csets allocated */ - struct re_guts *g; -# define NPAREN 10 /* we need to remember () 1-9 for back refs */ - sopno pbegin[NPAREN]; /* -> ( ([0] unused) */ - sopno pend[NPAREN]; /* -> ) ([0] unused) */ -}; - -static void p_ere(struct parse *, int); -static void p_ere_exp(struct parse *); -static void p_str(struct parse *); -static void p_bre(struct parse *, int, int); -static int p_simp_re(struct parse *, int); -static int p_count(struct parse *); -static void p_bracket(struct parse *); -static void p_b_term(struct parse *, cset *); -static void p_b_cclass(struct parse *, cset *); -static void p_b_eclass(struct parse *, cset *); -static char p_b_symbol(struct parse *); -static char p_b_coll_elem(struct parse *, int); -static char othercase(int); -static void bothcases(struct parse *, int); -static void ordinary(struct parse *, int); -static void nonnewline(struct parse *); -static void repeat(struct parse *, sopno, int, int); -static int seterr(struct parse *, int); -static cset *allocset(struct parse *); -static void freeset(struct parse *, cset *); -static int freezeset(struct parse *, cset *); -static int firstch(struct parse *, cset *); -static int nch(struct parse *, cset *); -static void mcadd(struct parse *, cset *, const char *); -static void mcinvert(struct parse *, cset *); -static void mccase(struct parse *, cset *); -static int isinsets(struct re_guts *, int); -static int samesets(struct re_guts *, int, int); -static void categorize(struct parse *, struct re_guts *); -static sopno dupl(struct parse *, sopno, sopno); -static void doemit(struct parse *, sop, size_t); -static void doinsert(struct parse *, sop, size_t, sopno); -static void dofwd(struct parse *, sopno, sop); -static void enlarge(struct parse *, sopno); -static void stripsnug(struct parse *, struct re_guts *); -static void findmust(struct parse *, struct re_guts *); -static sopno pluscount(struct parse *, struct re_guts *); - -static char nuls[10]; /* place to point scanner in event of error */ - -/* - * macros for use with parse structure - * BEWARE: these know that the parse structure is named `p' !!! - */ -#define PEEK() (*p->next) -#define PEEK2() (*(p->next+1)) -#define MORE() (p->next < p->end) -#define MORE2() (p->next+1 < p->end) -#define SEE(c) (MORE() && PEEK() == (c)) -#define SEETWO(a, b) (MORE() && MORE2() && PEEK() == (a) && PEEK2() == (b)) -#define EAT(c) ((SEE(c)) ? (NEXT(), 1) : 0) -#define EATTWO(a, b) ((SEETWO(a, b)) ? (NEXT2(), 1) : 0) -#define NEXT() (p->next++) -#define NEXT2() (p->next += 2) -#define NEXTn(n) (p->next += (n)) -#define GETNEXT() (*p->next++) -#define SETERROR(e) seterr(p, (e)) -#define REQUIRE(co, e) (void)((co) || SETERROR(e)) -#define MUSTSEE(c, e) (REQUIRE(MORE() && PEEK() == (c), e)) -#define MUSTEAT(c, e) (REQUIRE(MORE() && GETNEXT() == (c), e)) -#define MUSTNOTSEE(c, e) (REQUIRE(!MORE() || PEEK() != (c), e)) -#define EMIT(op, sopnd) doemit(p, (sop)(op), (size_t)(sopnd)) -#define INSERT(op, pos) doinsert(p, (sop)(op), HERE()-(pos)+1, pos) -#define AHEAD(pos) dofwd(p, pos, HERE()-(pos)) -#define ASTERN(sop, pos) EMIT(sop, HERE()-pos) -#define HERE() (p->slen) -#define THERE() (p->slen - 1) -#define THERETHERE() (p->slen - 2) -#define DROP(n) (p->slen -= (n)) - -#ifdef _POSIX2_RE_DUP_MAX -#define DUPMAX _POSIX2_RE_DUP_MAX -#else -#define DUPMAX 255 -#endif -#define INFINITY (DUPMAX + 1) - -#ifndef NDEBUG -static int never = 0; /* for use in asserts; shuts lint up */ -#else -#define never 0 /* some <assert.h>s have bugs too */ -#endif - -/* - - llvm_regcomp - interface for parser and compilation - */ -int /* 0 success, otherwise REG_something */ -llvm_regcomp(llvm_regex_t *preg, const char *pattern, int cflags) -{ - struct parse pa; - struct re_guts *g; - struct parse *p = &pa; - int i; - size_t len; -#ifdef REDEBUG -# define GOODFLAGS(f) (f) -#else -# define GOODFLAGS(f) ((f)&~REG_DUMP) -#endif - - cflags = GOODFLAGS(cflags); - if ((cflags®_EXTENDED) && (cflags®_NOSPEC)) - return(REG_INVARG); - - if (cflags®_PEND) { - if (preg->re_endp < pattern) - return(REG_INVARG); - len = preg->re_endp - pattern; - } else - len = strlen((const char *)pattern); - - /* do the mallocs early so failure handling is easy */ - g = (struct re_guts *)malloc(sizeof(struct re_guts) + - (NC-1)*sizeof(cat_t)); - if (g == NULL) - return(REG_ESPACE); - p->ssize = len/(size_t)2*(size_t)3 + (size_t)1; /* ugh */ - p->strip = (sop *)calloc(p->ssize, sizeof(sop)); - p->slen = 0; - if (p->strip == NULL) { - free((char *)g); - return(REG_ESPACE); - } - - /* set things up */ - p->g = g; - p->next = (char *)pattern; /* convenience; we do not modify it */ - p->end = p->next + len; - p->error = 0; - p->ncsalloc = 0; - for (i = 0; i < NPAREN; i++) { - p->pbegin[i] = 0; - p->pend[i] = 0; - } - g->csetsize = NC; - g->sets = NULL; - g->setbits = NULL; - g->ncsets = 0; - g->cflags = cflags; - g->iflags = 0; - g->nbol = 0; - g->neol = 0; - g->must = NULL; - g->mlen = 0; - g->nsub = 0; - g->ncategories = 1; /* category 0 is "everything else" */ - g->categories = &g->catspace[-(CHAR_MIN)]; - (void) memset((char *)g->catspace, 0, NC*sizeof(cat_t)); - g->backrefs = 0; - - /* do it */ - EMIT(OEND, 0); - g->firststate = THERE(); - if (cflags®_EXTENDED) - p_ere(p, OUT); - else if (cflags®_NOSPEC) - p_str(p); - else - p_bre(p, OUT, OUT); - EMIT(OEND, 0); - g->laststate = THERE(); - - /* tidy up loose ends and fill things in */ - categorize(p, g); - stripsnug(p, g); - findmust(p, g); - g->nplus = pluscount(p, g); - g->magic = MAGIC2; - preg->re_nsub = g->nsub; - preg->re_g = g; - preg->re_magic = MAGIC1; -#ifndef REDEBUG - /* not debugging, so can't rely on the assert() in llvm_regexec() */ - if (g->iflags®EX_BAD) - SETERROR(REG_ASSERT); -#endif - - /* win or lose, we're done */ - if (p->error != 0) /* lose */ - llvm_regfree(preg); - return(p->error); -} - -/* - - p_ere - ERE parser top level, concatenation and alternation - */ -static void -p_ere(struct parse *p, int stop) /* character this ERE should end at */ -{ - char c; - sopno prevback = 0; - sopno prevfwd = 0; - sopno conc; - int first = 1; /* is this the first alternative? */ - - for (;;) { - /* do a bunch of concatenated expressions */ - conc = HERE(); - while (MORE() && (c = PEEK()) != '|' && c != stop) - p_ere_exp(p); - REQUIRE(HERE() != conc, REG_EMPTY); /* require nonempty */ - - if (!EAT('|')) - break; /* NOTE BREAK OUT */ - - if (first) { - INSERT(OCH_, conc); /* offset is wrong */ - prevfwd = conc; - prevback = conc; - first = 0; - } - ASTERN(OOR1, prevback); - prevback = THERE(); - AHEAD(prevfwd); /* fix previous offset */ - prevfwd = HERE(); - EMIT(OOR2, 0); /* offset is very wrong */ - } - - if (!first) { /* tail-end fixups */ - AHEAD(prevfwd); - ASTERN(O_CH, prevback); - } - - assert(!MORE() || SEE(stop)); -} - -/* - - p_ere_exp - parse one subERE, an atom possibly followed by a repetition op - */ -static void -p_ere_exp(struct parse *p) -{ - char c; - sopno pos; - int count; - int count2; - int backrefnum; - sopno subno; - int wascaret = 0; - - assert(MORE()); /* caller should have ensured this */ - c = GETNEXT(); - - pos = HERE(); - switch (c) { - case '(': - REQUIRE(MORE(), REG_EPAREN); - p->g->nsub++; - subno = p->g->nsub; - if (subno < NPAREN) - p->pbegin[subno] = HERE(); - EMIT(OLPAREN, subno); - if (!SEE(')')) - p_ere(p, ')'); - if (subno < NPAREN) { - p->pend[subno] = HERE(); - assert(p->pend[subno] != 0); - } - EMIT(ORPAREN, subno); - MUSTEAT(')', REG_EPAREN); - break; -#ifndef POSIX_MISTAKE - case ')': /* happens only if no current unmatched ( */ - /* - * You may ask, why the ifndef? Because I didn't notice - * this until slightly too late for 1003.2, and none of the - * other 1003.2 regular-expression reviewers noticed it at - * all. So an unmatched ) is legal POSIX, at least until - * we can get it fixed. - */ - SETERROR(REG_EPAREN); - break; -#endif - case '^': - EMIT(OBOL, 0); - p->g->iflags |= USEBOL; - p->g->nbol++; - wascaret = 1; - break; - case '$': - EMIT(OEOL, 0); - p->g->iflags |= USEEOL; - p->g->neol++; - break; - case '|': - SETERROR(REG_EMPTY); - break; - case '*': - case '+': - case '?': - SETERROR(REG_BADRPT); - break; - case '.': - if (p->g->cflags®_NEWLINE) - nonnewline(p); - else - EMIT(OANY, 0); - break; - case '[': - p_bracket(p); - break; - case '\\': - REQUIRE(MORE(), REG_EESCAPE); - c = GETNEXT(); - if (c >= '1' && c <= '9') { - /* \[0-9] is taken to be a back-reference to a previously specified - * matching group. backrefnum will hold the number. The matching - * group must exist (i.e. if \4 is found there must have been at - * least 4 matching groups specified in the pattern previously). - */ - backrefnum = c - '0'; - if (p->pend[backrefnum] == 0) { - SETERROR(REG_ESUBREG); - break; - } - - /* Make sure everything checks out and emit the sequence - * that marks a back-reference to the parse structure. - */ - assert(backrefnum <= p->g->nsub); - EMIT(OBACK_, backrefnum); - assert(p->pbegin[backrefnum] != 0); - assert(OP(p->strip[p->pbegin[backrefnum]]) != OLPAREN); - assert(OP(p->strip[p->pend[backrefnum]]) != ORPAREN); - (void) dupl(p, p->pbegin[backrefnum]+1, p->pend[backrefnum]); - EMIT(O_BACK, backrefnum); - p->g->backrefs = 1; - } else { - /* Other chars are simply themselves when escaped with a backslash. - */ - ordinary(p, c); - } - break; - case '{': /* okay as ordinary except if digit follows */ - REQUIRE(!MORE() || !isdigit((uch)PEEK()), REG_BADRPT); - /* FALLTHROUGH */ - default: - ordinary(p, c); - break; - } - - if (!MORE()) - return; - c = PEEK(); - /* we call { a repetition if followed by a digit */ - if (!( c == '*' || c == '+' || c == '?' || - (c == '{' && MORE2() && isdigit((uch)PEEK2())) )) - return; /* no repetition, we're done */ - NEXT(); - - REQUIRE(!wascaret, REG_BADRPT); - switch (c) { - case '*': /* implemented as +? */ - /* this case does not require the (y|) trick, noKLUDGE */ - INSERT(OPLUS_, pos); - ASTERN(O_PLUS, pos); - INSERT(OQUEST_, pos); - ASTERN(O_QUEST, pos); - break; - case '+': - INSERT(OPLUS_, pos); - ASTERN(O_PLUS, pos); - break; - case '?': - /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ - INSERT(OCH_, pos); /* offset slightly wrong */ - ASTERN(OOR1, pos); /* this one's right */ - AHEAD(pos); /* fix the OCH_ */ - EMIT(OOR2, 0); /* offset very wrong... */ - AHEAD(THERE()); /* ...so fix it */ - ASTERN(O_CH, THERETHERE()); - break; - case '{': - count = p_count(p); - if (EAT(',')) { - if (isdigit((uch)PEEK())) { - count2 = p_count(p); - REQUIRE(count <= count2, REG_BADBR); - } else /* single number with comma */ - count2 = INFINITY; - } else /* just a single number */ - count2 = count; - repeat(p, pos, count, count2); - if (!EAT('}')) { /* error heuristics */ - while (MORE() && PEEK() != '}') - NEXT(); - REQUIRE(MORE(), REG_EBRACE); - SETERROR(REG_BADBR); - } - break; - } - - if (!MORE()) - return; - c = PEEK(); - if (!( c == '*' || c == '+' || c == '?' || - (c == '{' && MORE2() && isdigit((uch)PEEK2())) ) ) - return; - SETERROR(REG_BADRPT); -} - -/* - - p_str - string (no metacharacters) "parser" - */ -static void -p_str(struct parse *p) -{ - REQUIRE(MORE(), REG_EMPTY); - while (MORE()) - ordinary(p, GETNEXT()); -} - -/* - - p_bre - BRE parser top level, anchoring and concatenation - * Giving end1 as OUT essentially eliminates the end1/end2 check. - * - * This implementation is a bit of a kludge, in that a trailing $ is first - * taken as an ordinary character and then revised to be an anchor. The - * only undesirable side effect is that '$' gets included as a character - * category in such cases. This is fairly harmless; not worth fixing. - * The amount of lookahead needed to avoid this kludge is excessive. - */ -static void -p_bre(struct parse *p, - int end1, /* first terminating character */ - int end2) /* second terminating character */ -{ - sopno start = HERE(); - int first = 1; /* first subexpression? */ - int wasdollar = 0; - - if (EAT('^')) { - EMIT(OBOL, 0); - p->g->iflags |= USEBOL; - p->g->nbol++; - } - while (MORE() && !SEETWO(end1, end2)) { - wasdollar = p_simp_re(p, first); - first = 0; - } - if (wasdollar) { /* oops, that was a trailing anchor */ - DROP(1); - EMIT(OEOL, 0); - p->g->iflags |= USEEOL; - p->g->neol++; - } - - REQUIRE(HERE() != start, REG_EMPTY); /* require nonempty */ -} - -/* - - p_simp_re - parse a simple RE, an atom possibly followed by a repetition - */ -static int /* was the simple RE an unbackslashed $? */ -p_simp_re(struct parse *p, - int starordinary) /* is a leading * an ordinary character? */ -{ - int c; - int count; - int count2; - sopno pos; - int i; - sopno subno; -# define BACKSL (1<<CHAR_BIT) - - pos = HERE(); /* repetition op, if any, covers from here */ - - assert(MORE()); /* caller should have ensured this */ - c = GETNEXT(); - if (c == '\\') { - REQUIRE(MORE(), REG_EESCAPE); - c = BACKSL | GETNEXT(); - } - switch (c) { - case '.': - if (p->g->cflags®_NEWLINE) - nonnewline(p); - else - EMIT(OANY, 0); - break; - case '[': - p_bracket(p); - break; - case BACKSL|'{': - SETERROR(REG_BADRPT); - break; - case BACKSL|'(': - p->g->nsub++; - subno = p->g->nsub; - if (subno < NPAREN) - p->pbegin[subno] = HERE(); - EMIT(OLPAREN, subno); - /* the MORE here is an error heuristic */ - if (MORE() && !SEETWO('\\', ')')) - p_bre(p, '\\', ')'); - if (subno < NPAREN) { - p->pend[subno] = HERE(); - assert(p->pend[subno] != 0); - } - EMIT(ORPAREN, subno); - REQUIRE(EATTWO('\\', ')'), REG_EPAREN); - break; - case BACKSL|')': /* should not get here -- must be user */ - case BACKSL|'}': - SETERROR(REG_EPAREN); - break; - case BACKSL|'1': - case BACKSL|'2': - case BACKSL|'3': - case BACKSL|'4': - case BACKSL|'5': - case BACKSL|'6': - case BACKSL|'7': - case BACKSL|'8': - case BACKSL|'9': - i = (c&~BACKSL) - '0'; - assert(i < NPAREN); - if (p->pend[i] != 0) { - assert(i <= p->g->nsub); - EMIT(OBACK_, i); - assert(p->pbegin[i] != 0); - assert(OP(p->strip[p->pbegin[i]]) == OLPAREN); - assert(OP(p->strip[p->pend[i]]) == ORPAREN); - (void) dupl(p, p->pbegin[i]+1, p->pend[i]); - EMIT(O_BACK, i); - } else - SETERROR(REG_ESUBREG); - p->g->backrefs = 1; - break; - case '*': - REQUIRE(starordinary, REG_BADRPT); - /* FALLTHROUGH */ - default: - ordinary(p, (char)c); - break; - } - - if (EAT('*')) { /* implemented as +? */ - /* this case does not require the (y|) trick, noKLUDGE */ - INSERT(OPLUS_, pos); - ASTERN(O_PLUS, pos); - INSERT(OQUEST_, pos); - ASTERN(O_QUEST, pos); - } else if (EATTWO('\\', '{')) { - count = p_count(p); - if (EAT(',')) { - if (MORE() && isdigit((uch)PEEK())) { - count2 = p_count(p); - REQUIRE(count <= count2, REG_BADBR); - } else /* single number with comma */ - count2 = INFINITY; - } else /* just a single number */ - count2 = count; - repeat(p, pos, count, count2); - if (!EATTWO('\\', '}')) { /* error heuristics */ - while (MORE() && !SEETWO('\\', '}')) - NEXT(); - REQUIRE(MORE(), REG_EBRACE); - SETERROR(REG_BADBR); - } - } else if (c == '$') /* $ (but not \$) ends it */ - return(1); - - return(0); -} - -/* - - p_count - parse a repetition count - */ -static int /* the value */ -p_count(struct parse *p) -{ - int count = 0; - int ndigits = 0; - - while (MORE() && isdigit((uch)PEEK()) && count <= DUPMAX) { - count = count*10 + (GETNEXT() - '0'); - ndigits++; - } - - REQUIRE(ndigits > 0 && count <= DUPMAX, REG_BADBR); - return(count); -} - -/* - - p_bracket - parse a bracketed character list - * - * Note a significant property of this code: if the allocset() did SETERROR, - * no set operations are done. - */ -static void -p_bracket(struct parse *p) -{ - cset *cs; - int invert = 0; - - /* Dept of Truly Sickening Special-Case Kludges */ - if (p->next + 5 < p->end && strncmp(p->next, "[:<:]]", 6) == 0) { - EMIT(OBOW, 0); - NEXTn(6); - return; - } - if (p->next + 5 < p->end && strncmp(p->next, "[:>:]]", 6) == 0) { - EMIT(OEOW, 0); - NEXTn(6); - return; - } - - if ((cs = allocset(p)) == NULL) { - /* allocset did set error status in p */ - return; - } - - if (EAT('^')) - invert++; /* make note to invert set at end */ - if (EAT(']')) - CHadd(cs, ']'); - else if (EAT('-')) - CHadd(cs, '-'); - while (MORE() && PEEK() != ']' && !SEETWO('-', ']')) - p_b_term(p, cs); - if (EAT('-')) - CHadd(cs, '-'); - MUSTEAT(']', REG_EBRACK); - - if (p->error != 0) { /* don't mess things up further */ - freeset(p, cs); - return; - } - - if (p->g->cflags®_ICASE) { - int i; - int ci; - - for (i = p->g->csetsize - 1; i >= 0; i--) - if (CHIN(cs, i) && isalpha(i)) { - ci = othercase(i); - if (ci != i) - CHadd(cs, ci); - } - if (cs->multis != NULL) - mccase(p, cs); - } - if (invert) { - int i; - - for (i = p->g->csetsize - 1; i >= 0; i--) - if (CHIN(cs, i)) - CHsub(cs, i); - else - CHadd(cs, i); - if (p->g->cflags®_NEWLINE) - CHsub(cs, '\n'); - if (cs->multis != NULL) - mcinvert(p, cs); - } - - assert(cs->multis == NULL); /* xxx */ - - if (nch(p, cs) == 1) { /* optimize singleton sets */ - ordinary(p, firstch(p, cs)); - freeset(p, cs); - } else - EMIT(OANYOF, freezeset(p, cs)); -} - -/* - - p_b_term - parse one term of a bracketed character list - */ -static void -p_b_term(struct parse *p, cset *cs) -{ - char c; - char start, finish; - int i; - - /* classify what we've got */ - switch ((MORE()) ? PEEK() : '\0') { - case '[': - c = (MORE2()) ? PEEK2() : '\0'; - break; - case '-': - SETERROR(REG_ERANGE); - return; /* NOTE RETURN */ - break; - default: - c = '\0'; - break; - } - - switch (c) { - case ':': /* character class */ - NEXT2(); - REQUIRE(MORE(), REG_EBRACK); - c = PEEK(); - REQUIRE(c != '-' && c != ']', REG_ECTYPE); - p_b_cclass(p, cs); - REQUIRE(MORE(), REG_EBRACK); - REQUIRE(EATTWO(':', ']'), REG_ECTYPE); - break; - case '=': /* equivalence class */ - NEXT2(); - REQUIRE(MORE(), REG_EBRACK); - c = PEEK(); - REQUIRE(c != '-' && c != ']', REG_ECOLLATE); - p_b_eclass(p, cs); - REQUIRE(MORE(), REG_EBRACK); - REQUIRE(EATTWO('=', ']'), REG_ECOLLATE); - break; - default: /* symbol, ordinary character, or range */ -/* xxx revision needed for multichar stuff */ - start = p_b_symbol(p); - if (SEE('-') && MORE2() && PEEK2() != ']') { - /* range */ - NEXT(); - if (EAT('-')) - finish = '-'; - else - finish = p_b_symbol(p); - } else - finish = start; -/* xxx what about signed chars here... */ - REQUIRE(start <= finish, REG_ERANGE); - for (i = start; i <= finish; i++) - CHadd(cs, i); - break; - } -} - -/* - - p_b_cclass - parse a character-class name and deal with it - */ -static void -p_b_cclass(struct parse *p, cset *cs) -{ - char *sp = p->next; - struct cclass *cp; - size_t len; - const char *u; - char c; - - while (MORE() && isalpha((uch)PEEK())) - NEXT(); - len = p->next - sp; - for (cp = cclasses; cp->name != NULL; cp++) - if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0') - break; - if (cp->name == NULL) { - /* oops, didn't find it */ - SETERROR(REG_ECTYPE); - return; - } - - u = cp->chars; - while ((c = *u++) != '\0') - CHadd(cs, c); - for (u = cp->multis; *u != '\0'; u += strlen(u) + 1) - MCadd(p, cs, u); -} - -/* - - p_b_eclass - parse an equivalence-class name and deal with it - * - * This implementation is incomplete. xxx - */ -static void -p_b_eclass(struct parse *p, cset *cs) -{ - char c; - - c = p_b_coll_elem(p, '='); - CHadd(cs, c); -} - -/* - - p_b_symbol - parse a character or [..]ed multicharacter collating symbol - */ -static char /* value of symbol */ -p_b_symbol(struct parse *p) -{ - char value; - - REQUIRE(MORE(), REG_EBRACK); - if (!EATTWO('[', '.')) - return(GETNEXT()); - - /* collating symbol */ - value = p_b_coll_elem(p, '.'); - REQUIRE(EATTWO('.', ']'), REG_ECOLLATE); - return(value); -} - -/* - - p_b_coll_elem - parse a collating-element name and look it up - */ -static char /* value of collating element */ -p_b_coll_elem(struct parse *p, - int endc) /* name ended by endc,']' */ -{ - char *sp = p->next; - struct cname *cp; - size_t len; - - while (MORE() && !SEETWO(endc, ']')) - NEXT(); - if (!MORE()) { - SETERROR(REG_EBRACK); - return(0); - } - len = p->next - sp; - for (cp = cnames; cp->name != NULL; cp++) - if (strncmp(cp->name, sp, len) == 0 && strlen(cp->name) == len) - return(cp->code); /* known name */ - if (len == 1) - return(*sp); /* single character */ - SETERROR(REG_ECOLLATE); /* neither */ - return(0); -} - -/* - - othercase - return the case counterpart of an alphabetic - */ -static char /* if no counterpart, return ch */ -othercase(int ch) -{ - ch = (uch)ch; - assert(isalpha(ch)); - if (isupper(ch)) - return ((uch)tolower(ch)); - else if (islower(ch)) - return ((uch)toupper(ch)); - else /* peculiar, but could happen */ - return(ch); -} - -/* - - bothcases - emit a dualcase version of a two-case character - * - * Boy, is this implementation ever a kludge... - */ -static void -bothcases(struct parse *p, int ch) -{ - char *oldnext = p->next; - char *oldend = p->end; - char bracket[3]; - - ch = (uch)ch; - assert(othercase(ch) != ch); /* p_bracket() would recurse */ - p->next = bracket; - p->end = bracket+2; - bracket[0] = ch; - bracket[1] = ']'; - bracket[2] = '\0'; - p_bracket(p); - assert(p->next == bracket+2); - p->next = oldnext; - p->end = oldend; -} - -/* - - ordinary - emit an ordinary character - */ -static void -ordinary(struct parse *p, int ch) -{ - cat_t *cap = p->g->categories; - - if ((p->g->cflags®_ICASE) && isalpha((uch)ch) && othercase(ch) != ch) - bothcases(p, ch); - else { - EMIT(OCHAR, (uch)ch); - if (cap[ch] == 0) - cap[ch] = p->g->ncategories++; - } -} - -/* - - nonnewline - emit REG_NEWLINE version of OANY - * - * Boy, is this implementation ever a kludge... - */ -static void -nonnewline(struct parse *p) -{ - char *oldnext = p->next; - char *oldend = p->end; - char bracket[4]; - - p->next = bracket; - p->end = bracket+3; - bracket[0] = '^'; - bracket[1] = '\n'; - bracket[2] = ']'; - bracket[3] = '\0'; - p_bracket(p); - assert(p->next == bracket+3); - p->next = oldnext; - p->end = oldend; -} - -/* - - repeat - generate code for a bounded repetition, recursively if needed - */ -static void -repeat(struct parse *p, - sopno start, /* operand from here to end of strip */ - int from, /* repeated from this number */ - int to) /* to this number of times (maybe INFINITY) */ -{ - sopno finish = HERE(); -# define N 2 -# define INF 3 -# define REP(f, t) ((f)*8 + (t)) -# define MAP(n) (((n) <= 1) ? (n) : ((n) == INFINITY) ? INF : N) - sopno copy; - - if (p->error != 0) /* head off possible runaway recursion */ - return; - - assert(from <= to); - - switch (REP(MAP(from), MAP(to))) { - case REP(0, 0): /* must be user doing this */ - DROP(finish-start); /* drop the operand */ - break; - case REP(0, 1): /* as x{1,1}? */ - case REP(0, N): /* as x{1,n}? */ - case REP(0, INF): /* as x{1,}? */ - /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ - INSERT(OCH_, start); /* offset is wrong... */ - repeat(p, start+1, 1, to); - ASTERN(OOR1, start); - AHEAD(start); /* ... fix it */ - EMIT(OOR2, 0); - AHEAD(THERE()); - ASTERN(O_CH, THERETHERE()); - break; - case REP(1, 1): /* trivial case */ - /* done */ - break; - case REP(1, N): /* as x?x{1,n-1} */ - /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ - INSERT(OCH_, start); - ASTERN(OOR1, start); - AHEAD(start); - EMIT(OOR2, 0); /* offset very wrong... */ - AHEAD(THERE()); /* ...so fix it */ - ASTERN(O_CH, THERETHERE()); - copy = dupl(p, start+1, finish+1); - assert(copy == finish+4); - repeat(p, copy, 1, to-1); - break; - case REP(1, INF): /* as x+ */ - INSERT(OPLUS_, start); - ASTERN(O_PLUS, start); - break; - case REP(N, N): /* as xx{m-1,n-1} */ - copy = dupl(p, start, finish); - repeat(p, copy, from-1, to-1); - break; - case REP(N, INF): /* as xx{n-1,INF} */ - copy = dupl(p, start, finish); - repeat(p, copy, from-1, to); - break; - default: /* "can't happen" */ - SETERROR(REG_ASSERT); /* just in case */ - break; - } -} - -/* - - seterr - set an error condition - */ -static int /* useless but makes type checking happy */ -seterr(struct parse *p, int e) -{ - if (p->error == 0) /* keep earliest error condition */ - p->error = e; - p->next = nuls; /* try to bring things to a halt */ - p->end = nuls; - return(0); /* make the return value well-defined */ -} - -/* - - allocset - allocate a set of characters for [] - */ -static cset * -allocset(struct parse *p) -{ - int no = p->g->ncsets++; - size_t nc; - size_t nbytes; - cset *cs; - size_t css = (size_t)p->g->csetsize; - int i; - - if (no >= p->ncsalloc) { /* need another column of space */ - void *ptr; - - p->ncsalloc += CHAR_BIT; - nc = p->ncsalloc; - if (nc > SIZE_MAX / sizeof(cset)) - goto nomem; - assert(nc % CHAR_BIT == 0); - nbytes = nc / CHAR_BIT * css; - - ptr = (cset *)realloc((char *)p->g->sets, nc * sizeof(cset)); - if (ptr == NULL) - goto nomem; - p->g->sets = ptr; - - ptr = (uch *)realloc((char *)p->g->setbits, nbytes); - if (ptr == NULL) - goto nomem; - p->g->setbits = ptr; - - for (i = 0; i < no; i++) - p->g->sets[i].ptr = p->g->setbits + css*(i/CHAR_BIT); - - (void) memset((char *)p->g->setbits + (nbytes - css), 0, css); - } - /* XXX should not happen */ - if (p->g->sets == NULL || p->g->setbits == NULL) - goto nomem; - - cs = &p->g->sets[no]; - cs->ptr = p->g->setbits + css*((no)/CHAR_BIT); - cs->mask = 1 << ((no) % CHAR_BIT); - cs->hash = 0; - cs->smultis = 0; - cs->multis = NULL; - - return(cs); -nomem: - free(p->g->sets); - p->g->sets = NULL; - free(p->g->setbits); - p->g->setbits = NULL; - - SETERROR(REG_ESPACE); - /* caller's responsibility not to do set ops */ - return(NULL); -} - -/* - - freeset - free a now-unused set - */ -static void -freeset(struct parse *p, cset *cs) -{ - size_t i; - cset *top = &p->g->sets[p->g->ncsets]; - size_t css = (size_t)p->g->csetsize; - - for (i = 0; i < css; i++) - CHsub(cs, i); - if (cs == top-1) /* recover only the easy case */ - p->g->ncsets--; -} - -/* - - freezeset - final processing on a set of characters - * - * The main task here is merging identical sets. This is usually a waste - * of time (although the hash code minimizes the overhead), but can win - * big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash - * is done using addition rather than xor -- all ASCII [aA] sets xor to - * the same value! - */ -static int /* set number */ -freezeset(struct parse *p, cset *cs) -{ - uch h = cs->hash; - size_t i; - cset *top = &p->g->sets[p->g->ncsets]; - cset *cs2; - size_t css = (size_t)p->g->csetsize; - - /* look for an earlier one which is the same */ - for (cs2 = &p->g->sets[0]; cs2 < top; cs2++) - if (cs2->hash == h && cs2 != cs) { - /* maybe */ - for (i = 0; i < css; i++) - if (!!CHIN(cs2, i) != !!CHIN(cs, i)) - break; /* no */ - if (i == css) - break; /* yes */ - } - - if (cs2 < top) { /* found one */ - freeset(p, cs); - cs = cs2; - } - - return((int)(cs - p->g->sets)); -} - -/* - - firstch - return first character in a set (which must have at least one) - */ -static int /* character; there is no "none" value */ -firstch(struct parse *p, cset *cs) -{ - size_t i; - size_t css = (size_t)p->g->csetsize; - - for (i = 0; i < css; i++) - if (CHIN(cs, i)) - return((char)i); - assert(never); - return(0); /* arbitrary */ -} - -/* - - nch - number of characters in a set - */ -static int -nch(struct parse *p, cset *cs) -{ - size_t i; - size_t css = (size_t)p->g->csetsize; - int n = 0; - - for (i = 0; i < css; i++) - if (CHIN(cs, i)) - n++; - return(n); -} - -/* - - mcadd - add a collating element to a cset - */ -static void -mcadd( struct parse *p, cset *cs, const char *cp) -{ - size_t oldend = cs->smultis; - void *np; - - cs->smultis += strlen(cp) + 1; - np = realloc(cs->multis, cs->smultis); - if (np == NULL) { - if (cs->multis) - free(cs->multis); - cs->multis = NULL; - SETERROR(REG_ESPACE); - return; - } - cs->multis = np; - - llvm_strlcpy(cs->multis + oldend - 1, cp, cs->smultis - oldend + 1); -} - -/* - - mcinvert - invert the list of collating elements in a cset - * - * This would have to know the set of possibilities. Implementation - * is deferred. - */ -/* ARGSUSED */ -static void -mcinvert(struct parse *p, cset *cs) -{ - assert(cs->multis == NULL); /* xxx */ -} - -/* - - mccase - add case counterparts of the list of collating elements in a cset - * - * This would have to know the set of possibilities. Implementation - * is deferred. - */ -/* ARGSUSED */ -static void -mccase(struct parse *p, cset *cs) -{ - assert(cs->multis == NULL); /* xxx */ -} - -/* - - isinsets - is this character in any sets? - */ -static int /* predicate */ -isinsets(struct re_guts *g, int c) -{ - uch *col; - int i; - int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT; - unsigned uc = (uch)c; - - for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) - if (col[uc] != 0) - return(1); - return(0); -} - -/* - - samesets - are these two characters in exactly the same sets? - */ -static int /* predicate */ -samesets(struct re_guts *g, int c1, int c2) -{ - uch *col; - int i; - int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT; - unsigned uc1 = (uch)c1; - unsigned uc2 = (uch)c2; - - for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) - if (col[uc1] != col[uc2]) - return(0); - return(1); -} - -/* - - categorize - sort out character categories - */ -static void -categorize(struct parse *p, struct re_guts *g) -{ - cat_t *cats = g->categories; - int c; - int c2; - cat_t cat; - - /* avoid making error situations worse */ - if (p->error != 0) - return; - - for (c = CHAR_MIN; c <= CHAR_MAX; c++) - if (cats[c] == 0 && isinsets(g, c)) { - cat = g->ncategories++; - cats[c] = cat; - for (c2 = c+1; c2 <= CHAR_MAX; c2++) - if (cats[c2] == 0 && samesets(g, c, c2)) - cats[c2] = cat; - } -} - -/* - - dupl - emit a duplicate of a bunch of sops - */ -static sopno /* start of duplicate */ -dupl(struct parse *p, - sopno start, /* from here */ - sopno finish) /* to this less one */ -{ - sopno ret = HERE(); - sopno len = finish - start; - - assert(finish >= start); - if (len == 0) - return(ret); - enlarge(p, p->ssize + len); /* this many unexpected additions */ - assert(p->ssize >= p->slen + len); - (void) memmove((char *)(p->strip + p->slen), - (char *)(p->strip + start), (size_t)len*sizeof(sop)); - p->slen += len; - return(ret); -} - -/* - - doemit - emit a strip operator - * - * It might seem better to implement this as a macro with a function as - * hard-case backup, but it's just too big and messy unless there are - * some changes to the data structures. Maybe later. - */ -static void -doemit(struct parse *p, sop op, size_t opnd) -{ - /* avoid making error situations worse */ - if (p->error != 0) - return; - - /* deal with oversize operands ("can't happen", more or less) */ - assert(opnd < 1<<OPSHIFT); - - /* deal with undersized strip */ - if (p->slen >= p->ssize) - enlarge(p, (p->ssize+1) / 2 * 3); /* +50% */ - assert(p->slen < p->ssize); - - /* finally, it's all reduced to the easy case */ - p->strip[p->slen++] = SOP(op, opnd); -} - -/* - - doinsert - insert a sop into the strip - */ -static void -doinsert(struct parse *p, sop op, size_t opnd, sopno pos) -{ - sopno sn; - sop s; - int i; - - /* avoid making error situations worse */ - if (p->error != 0) - return; - - sn = HERE(); - EMIT(op, opnd); /* do checks, ensure space */ - assert(HERE() == sn+1); - s = p->strip[sn]; - - /* adjust paren pointers */ - assert(pos > 0); - for (i = 1; i < NPAREN; i++) { - if (p->pbegin[i] >= pos) { - p->pbegin[i]++; - } - if (p->pend[i] >= pos) { - p->pend[i]++; - } - } - - memmove((char *)&p->strip[pos+1], (char *)&p->strip[pos], - (HERE()-pos-1)*sizeof(sop)); - p->strip[pos] = s; -} - -/* - - dofwd - complete a forward reference - */ -static void -dofwd(struct parse *p, sopno pos, sop value) -{ - /* avoid making error situations worse */ - if (p->error != 0) - return; - - assert(value < 1<<OPSHIFT); - p->strip[pos] = OP(p->strip[pos]) | value; -} - -/* - - enlarge - enlarge the strip - */ -static void -enlarge(struct parse *p, sopno size) -{ - sop *sp; - - if (p->ssize >= size) - return; - - if ((uintptr_t)size > SIZE_MAX / sizeof(sop)) { - SETERROR(REG_ESPACE); - return; - } - - sp = (sop *)realloc(p->strip, size*sizeof(sop)); - if (sp == NULL) { - SETERROR(REG_ESPACE); - return; - } - p->strip = sp; - p->ssize = size; -} - -/* - - stripsnug - compact the strip - */ -static void -stripsnug(struct parse *p, struct re_guts *g) -{ - g->nstates = p->slen; - if ((uintptr_t)p->slen > SIZE_MAX / sizeof(sop)) { - g->strip = p->strip; - SETERROR(REG_ESPACE); - return; - } - - g->strip = (sop *)realloc((char *)p->strip, p->slen * sizeof(sop)); - if (g->strip == NULL) { - SETERROR(REG_ESPACE); - g->strip = p->strip; - } -} - -/* - - findmust - fill in must and mlen with longest mandatory literal string - * - * This algorithm could do fancy things like analyzing the operands of | - * for common subsequences. Someday. This code is simple and finds most - * of the interesting cases. - * - * Note that must and mlen got initialized during setup. - */ -static void -findmust(struct parse *p, struct re_guts *g) -{ - sop *scan; - sop *start = 0; /* start initialized in the default case, after that */ - sop *newstart = 0; /* newstart was initialized in the OCHAR case */ - sopno newlen; - sop s; - char *cp; - sopno i; - - /* avoid making error situations worse */ - if (p->error != 0) - return; - - /* find the longest OCHAR sequence in strip */ - newlen = 0; - scan = g->strip + 1; - do { - s = *scan++; - switch (OP(s)) { - case OCHAR: /* sequence member */ - if (newlen == 0) /* new sequence */ - newstart = scan - 1; - newlen++; - break; - case OPLUS_: /* things that don't break one */ - case OLPAREN: - case ORPAREN: - break; - case OQUEST_: /* things that must be skipped */ - case OCH_: - scan--; - do { - scan += OPND(s); - s = *scan; - /* assert() interferes w debug printouts */ - if (OP(s) != O_QUEST && OP(s) != O_CH && - OP(s) != OOR2) { - g->iflags |= REGEX_BAD; - return; - } - } while (OP(s) != O_QUEST && OP(s) != O_CH); - /* fallthrough */ - default: /* things that break a sequence */ - if (newlen > g->mlen) { /* ends one */ - start = newstart; - g->mlen = newlen; - } - newlen = 0; - break; - } - } while (OP(s) != OEND); - - if (g->mlen == 0) /* there isn't one */ - return; - - /* turn it into a character string */ - g->must = malloc((size_t)g->mlen + 1); - if (g->must == NULL) { /* argh; just forget it */ - g->mlen = 0; - return; - } - cp = g->must; - scan = start; - for (i = g->mlen; i > 0; i--) { - while (OP(s = *scan++) != OCHAR) - continue; - assert(cp < g->must + g->mlen); - *cp++ = (char)OPND(s); - } - assert(cp == g->must + g->mlen); - *cp++ = '\0'; /* just on general principles */ -} - -/* - - pluscount - count + nesting - */ -static sopno /* nesting depth */ -pluscount(struct parse *p, struct re_guts *g) -{ - sop *scan; - sop s; - sopno plusnest = 0; - sopno maxnest = 0; - - if (p->error != 0) - return(0); /* there may not be an OEND */ - - scan = g->strip + 1; - do { - s = *scan++; - switch (OP(s)) { - case OPLUS_: - plusnest++; - break; - case O_PLUS: - if (plusnest > maxnest) - maxnest = plusnest; - plusnest--; - break; - } - } while (OP(s) != OEND); - if (plusnest != 0) - g->iflags |= REGEX_BAD; - return(maxnest); -} |