+/*-
+ * 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 <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 "regcclass.h"
+#include "regcname.h"
+
+/*
+ * 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
+
+#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 = prevback;
+ sopno prevfwd = prevfwd;
+ 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;
+ 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();
+ 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(); /* repetion 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(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;
+ int 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 && cp->name[len] == '\0')
+ 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;
+ 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;
+
+ 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;
+ 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; /* start initialized in the default case, after that */
+ sop *newstart; /* 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);
+}
projects / oota-llvm.git / commitdiff