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Lookahead and lookbehind constraints aren't allowed to contain backrefs, and parentheses within them are always considered non-capturing. Or so says the manual. But the regexp parser forgot about these rules once inside a parenthesized subexpression, so that constructs like (\w)(?=(\1)) were accepted (but then not correctly executed --- a case like this acted like (\w)(?=\w), without any enforcement that the two \w's match the same text). And in (?=((foo))) the innermost parentheses would be counted as capturing parentheses, though no text would ever be captured for them. To fix, properly pass down the "type" argument to the recursive invocation of parse(). Back-patch to all supported branches; it was agreed that silent misexecution of such patterns is worse than throwing an error, even though new errors in minor releases are generally not desirable.
2222 lines
57 KiB
C
2222 lines
57 KiB
C
/*
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* re_*comp and friends - compile REs
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* This file #includes several others (see the bottom).
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*
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* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
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*
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* Development of this software was funded, in part, by Cray Research Inc.,
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* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
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* Corporation, none of whom are responsible for the results. The author
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* thanks all of them.
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*
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* Redistribution and use in source and binary forms -- with or without
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* modification -- are permitted for any purpose, provided that
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* redistributions in source form retain this entire copyright notice and
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* indicate the origin and nature of any modifications.
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*
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* I'd appreciate being given credit for this package in the documentation
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* of software which uses it, but that is not a requirement.
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*
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
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* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
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* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
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* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
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* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
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* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* src/backend/regex/regcomp.c
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*
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*/
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#include "regex/regguts.h"
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#include "miscadmin.h" /* needed by rcancelrequested/rstacktoodeep */
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/*
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* forward declarations, up here so forward datatypes etc. are defined early
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*/
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/* === regcomp.c === */
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static void moresubs(struct vars *, int);
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static int freev(struct vars *, int);
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static void makesearch(struct vars *, struct nfa *);
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static struct subre *parse(struct vars *, int, int, struct state *, struct state *);
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static struct subre *parsebranch(struct vars *, int, int, struct state *, struct state *, int);
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static void parseqatom(struct vars *, int, int, struct state *, struct state *, struct subre *);
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static void nonword(struct vars *, int, struct state *, struct state *);
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static void word(struct vars *, int, struct state *, struct state *);
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static int scannum(struct vars *);
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static void repeat(struct vars *, struct state *, struct state *, int, int);
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static void bracket(struct vars *, struct state *, struct state *);
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static void cbracket(struct vars *, struct state *, struct state *);
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static void brackpart(struct vars *, struct state *, struct state *);
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static const chr *scanplain(struct vars *);
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static void onechr(struct vars *, chr, struct state *, struct state *);
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static void dovec(struct vars *, struct cvec *, struct state *, struct state *);
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static void wordchrs(struct vars *);
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static void processlacon(struct vars *, struct state *, struct state *, int,
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struct state *, struct state *);
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static struct subre *subre(struct vars *, int, int, struct state *, struct state *);
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static void freesubre(struct vars *, struct subre *);
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static void freesrnode(struct vars *, struct subre *);
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static void optst(struct vars *, struct subre *);
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static int numst(struct subre *, int);
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static void markst(struct subre *);
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static void cleanst(struct vars *);
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static long nfatree(struct vars *, struct subre *, FILE *);
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static long nfanode(struct vars *, struct subre *, int, FILE *);
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static int newlacon(struct vars *, struct state *, struct state *, int);
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static void freelacons(struct subre *, int);
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static void rfree(regex_t *);
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static int rcancelrequested(void);
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static int rstacktoodeep(void);
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#ifdef REG_DEBUG
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static void dump(regex_t *, FILE *);
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static void dumpst(struct subre *, FILE *, int);
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static void stdump(struct subre *, FILE *, int);
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static const char *stid(struct subre *, char *, size_t);
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#endif
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/* === regc_lex.c === */
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static void lexstart(struct vars *);
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static void prefixes(struct vars *);
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static void lexnest(struct vars *, const chr *, const chr *);
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static void lexword(struct vars *);
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static int next(struct vars *);
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static int lexescape(struct vars *);
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static chr lexdigits(struct vars *, int, int, int);
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static int brenext(struct vars *, chr);
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static void skip(struct vars *);
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static chr newline(void);
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static chr chrnamed(struct vars *, const chr *, const chr *, chr);
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/* === regc_color.c === */
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static void initcm(struct vars *, struct colormap *);
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static void freecm(struct colormap *);
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static void cmtreefree(struct colormap *, union tree *, int);
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static color setcolor(struct colormap *, chr, pcolor);
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static color maxcolor(struct colormap *);
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static color newcolor(struct colormap *);
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static void freecolor(struct colormap *, pcolor);
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static color pseudocolor(struct colormap *);
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static color subcolor(struct colormap *, chr c);
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static color newsub(struct colormap *, pcolor);
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static void subrange(struct vars *, chr, chr, struct state *, struct state *);
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static void subblock(struct vars *, chr, struct state *, struct state *);
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static void okcolors(struct nfa *, struct colormap *);
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static void colorchain(struct colormap *, struct arc *);
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static void uncolorchain(struct colormap *, struct arc *);
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static void rainbow(struct nfa *, struct colormap *, int, pcolor, struct state *, struct state *);
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static void colorcomplement(struct nfa *, struct colormap *, int, struct state *, struct state *, struct state *);
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#ifdef REG_DEBUG
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static void dumpcolors(struct colormap *, FILE *);
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static void fillcheck(struct colormap *, union tree *, int, FILE *);
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static void dumpchr(chr, FILE *);
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#endif
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/* === regc_nfa.c === */
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static struct nfa *newnfa(struct vars *, struct colormap *, struct nfa *);
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static void freenfa(struct nfa *);
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static struct state *newstate(struct nfa *);
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static struct state *newfstate(struct nfa *, int flag);
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static void dropstate(struct nfa *, struct state *);
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static void freestate(struct nfa *, struct state *);
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static void destroystate(struct nfa *, struct state *);
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static void newarc(struct nfa *, int, pcolor, struct state *, struct state *);
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static void createarc(struct nfa *, int, pcolor, struct state *, struct state *);
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static struct arc *allocarc(struct nfa *, struct state *);
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static void freearc(struct nfa *, struct arc *);
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static void changearctarget(struct arc *, struct state *);
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static int hasnonemptyout(struct state *);
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static struct arc *findarc(struct state *, int, pcolor);
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static void cparc(struct nfa *, struct arc *, struct state *, struct state *);
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static void sortins(struct nfa *, struct state *);
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static int sortins_cmp(const void *, const void *);
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static void sortouts(struct nfa *, struct state *);
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static int sortouts_cmp(const void *, const void *);
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static void moveins(struct nfa *, struct state *, struct state *);
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static void copyins(struct nfa *, struct state *, struct state *);
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static void mergeins(struct nfa *, struct state *, struct arc **, int);
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static void moveouts(struct nfa *, struct state *, struct state *);
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static void copyouts(struct nfa *, struct state *, struct state *);
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static void cloneouts(struct nfa *, struct state *, struct state *, struct state *, int);
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static void delsub(struct nfa *, struct state *, struct state *);
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static void deltraverse(struct nfa *, struct state *, struct state *);
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static void dupnfa(struct nfa *, struct state *, struct state *, struct state *, struct state *);
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static void duptraverse(struct nfa *, struct state *, struct state *);
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static void cleartraverse(struct nfa *, struct state *);
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static struct state *single_color_transition(struct state *, struct state *);
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static void specialcolors(struct nfa *);
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static long optimize(struct nfa *, FILE *);
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static void pullback(struct nfa *, FILE *);
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static int pull(struct nfa *, struct arc *, struct state **);
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static void pushfwd(struct nfa *, FILE *);
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static int push(struct nfa *, struct arc *, struct state **);
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#define INCOMPATIBLE 1 /* destroys arc */
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#define SATISFIED 2 /* constraint satisfied */
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#define COMPATIBLE 3 /* compatible but not satisfied yet */
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static int combine(struct arc *, struct arc *);
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static void fixempties(struct nfa *, FILE *);
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static struct state *emptyreachable(struct nfa *, struct state *,
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struct state *, struct arc **);
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static int isconstraintarc(struct arc *);
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static int hasconstraintout(struct state *);
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static void fixconstraintloops(struct nfa *, FILE *);
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static int findconstraintloop(struct nfa *, struct state *);
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static void breakconstraintloop(struct nfa *, struct state *);
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static void clonesuccessorstates(struct nfa *, struct state *, struct state *,
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struct state *, struct arc *,
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char *, char *, int);
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static void cleanup(struct nfa *);
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static void markreachable(struct nfa *, struct state *, struct state *, struct state *);
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static void markcanreach(struct nfa *, struct state *, struct state *, struct state *);
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static long analyze(struct nfa *);
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static void compact(struct nfa *, struct cnfa *);
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static void carcsort(struct carc *, size_t);
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static int carc_cmp(const void *, const void *);
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static void freecnfa(struct cnfa *);
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static void dumpnfa(struct nfa *, FILE *);
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#ifdef REG_DEBUG
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static void dumpstate(struct state *, FILE *);
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static void dumparcs(struct state *, FILE *);
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static void dumparc(struct arc *, struct state *, FILE *);
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static void dumpcnfa(struct cnfa *, FILE *);
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static void dumpcstate(int, struct cnfa *, FILE *);
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#endif
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/* === regc_cvec.c === */
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static struct cvec *newcvec(int, int);
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static struct cvec *clearcvec(struct cvec *);
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static void addchr(struct cvec *, chr);
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static void addrange(struct cvec *, chr, chr);
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static struct cvec *getcvec(struct vars *, int, int);
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static void freecvec(struct cvec *);
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/* === regc_pg_locale.c === */
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static int pg_wc_isdigit(pg_wchar c);
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static int pg_wc_isalpha(pg_wchar c);
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static int pg_wc_isalnum(pg_wchar c);
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static int pg_wc_isupper(pg_wchar c);
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static int pg_wc_islower(pg_wchar c);
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static int pg_wc_isgraph(pg_wchar c);
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static int pg_wc_isprint(pg_wchar c);
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static int pg_wc_ispunct(pg_wchar c);
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static int pg_wc_isspace(pg_wchar c);
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static pg_wchar pg_wc_toupper(pg_wchar c);
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static pg_wchar pg_wc_tolower(pg_wchar c);
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/* === regc_locale.c === */
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static celt element(struct vars *, const chr *, const chr *);
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static struct cvec *range(struct vars *, celt, celt, int);
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static int before(celt, celt);
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static struct cvec *eclass(struct vars *, celt, int);
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static struct cvec *cclass(struct vars *, const chr *, const chr *, int);
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static struct cvec *allcases(struct vars *, chr);
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static int cmp(const chr *, const chr *, size_t);
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static int casecmp(const chr *, const chr *, size_t);
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/* internal variables, bundled for easy passing around */
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struct vars
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{
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regex_t *re;
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const chr *now; /* scan pointer into string */
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const chr *stop; /* end of string */
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const chr *savenow; /* saved now and stop for "subroutine call" */
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const chr *savestop;
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int err; /* error code (0 if none) */
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int cflags; /* copy of compile flags */
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int lasttype; /* type of previous token */
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int nexttype; /* type of next token */
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chr nextvalue; /* value (if any) of next token */
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int lexcon; /* lexical context type (see lex.c) */
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int nsubexp; /* subexpression count */
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struct subre **subs; /* subRE pointer vector */
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size_t nsubs; /* length of vector */
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struct subre *sub10[10]; /* initial vector, enough for most */
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struct nfa *nfa; /* the NFA */
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struct colormap *cm; /* character color map */
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color nlcolor; /* color of newline */
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struct state *wordchrs; /* state in nfa holding word-char outarcs */
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struct subre *tree; /* subexpression tree */
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struct subre *treechain; /* all tree nodes allocated */
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struct subre *treefree; /* any free tree nodes */
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int ntree; /* number of tree nodes, plus one */
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struct cvec *cv; /* interface cvec */
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struct cvec *cv2; /* utility cvec */
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struct subre *lacons; /* lookaround-constraint vector */
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int nlacons; /* size of lacons[]; note that only slots
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* numbered 1 .. nlacons-1 are used */
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size_t spaceused; /* approx. space used for compilation */
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};
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/* parsing macros; most know that `v' is the struct vars pointer */
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#define NEXT() (next(v)) /* advance by one token */
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#define SEE(t) (v->nexttype == (t)) /* is next token this? */
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#define EAT(t) (SEE(t) && next(v)) /* if next is this, swallow it */
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#define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
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#define ISERR() VISERR(v)
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#define VERR(vv,e) ((vv)->nexttype = EOS, \
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(vv)->err = ((vv)->err ? (vv)->err : (e)))
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#define ERR(e) VERR(v, e) /* record an error */
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#define NOERR() {if (ISERR()) return;} /* if error seen, return */
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#define NOERRN() {if (ISERR()) return NULL;} /* NOERR with retval */
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#define NOERRZ() {if (ISERR()) return 0;} /* NOERR with retval */
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#define INSIST(c, e) do { if (!(c)) ERR(e); } while (0) /* error if c false */
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#define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */
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#define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y)
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/* token type codes, some also used as NFA arc types */
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#define EMPTY 'n' /* no token present */
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#define EOS 'e' /* end of string */
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#define PLAIN 'p' /* ordinary character */
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#define DIGIT 'd' /* digit (in bound) */
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#define BACKREF 'b' /* back reference */
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#define COLLEL 'I' /* start of [. */
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#define ECLASS 'E' /* start of [= */
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#define CCLASS 'C' /* start of [: */
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#define END 'X' /* end of [. [= [: */
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#define RANGE 'R' /* - within [] which might be range delim. */
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#define LACON 'L' /* lookaround constraint subRE */
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#define AHEAD 'a' /* color-lookahead arc */
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#define BEHIND 'r' /* color-lookbehind arc */
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#define WBDRY 'w' /* word boundary constraint */
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#define NWBDRY 'W' /* non-word-boundary constraint */
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#define SBEGIN 'A' /* beginning of string (even if not BOL) */
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#define SEND 'Z' /* end of string (even if not EOL) */
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#define PREFER 'P' /* length preference */
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/* is an arc colored, and hence on a color chain? */
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#define COLORED(a) \
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((a)->type == PLAIN || (a)->type == AHEAD || (a)->type == BEHIND)
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/* static function list */
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static const struct fns functions = {
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rfree, /* regfree insides */
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rcancelrequested, /* check for cancel request */
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rstacktoodeep /* check for stack getting dangerously deep */
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};
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/*
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* pg_regcomp - compile regular expression
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*
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* Note: on failure, no resources remain allocated, so pg_regfree()
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* need not be applied to re.
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*/
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int
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pg_regcomp(regex_t *re,
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const chr *string,
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size_t len,
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int flags,
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Oid collation)
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{
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struct vars var;
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struct vars *v = &var;
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struct guts *g;
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int i;
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size_t j;
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#ifdef REG_DEBUG
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FILE *debug = (flags & REG_PROGRESS) ? stdout : (FILE *) NULL;
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#else
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FILE *debug = (FILE *) NULL;
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#endif
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#define CNOERR() { if (ISERR()) return freev(v, v->err); }
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/* sanity checks */
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if (re == NULL || string == NULL)
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return REG_INVARG;
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if ((flags & REG_QUOTE) &&
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(flags & (REG_ADVANCED | REG_EXPANDED | REG_NEWLINE)))
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return REG_INVARG;
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if (!(flags & REG_EXTENDED) && (flags & REG_ADVF))
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return REG_INVARG;
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/* Initialize locale-dependent support */
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pg_set_regex_collation(collation);
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/* initial setup (after which freev() is callable) */
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v->re = re;
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v->now = string;
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v->stop = v->now + len;
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v->savenow = v->savestop = NULL;
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v->err = 0;
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v->cflags = flags;
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v->nsubexp = 0;
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v->subs = v->sub10;
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v->nsubs = 10;
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for (j = 0; j < v->nsubs; j++)
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v->subs[j] = NULL;
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v->nfa = NULL;
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v->cm = NULL;
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v->nlcolor = COLORLESS;
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v->wordchrs = NULL;
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v->tree = NULL;
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v->treechain = NULL;
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v->treefree = NULL;
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v->cv = NULL;
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v->cv2 = NULL;
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v->lacons = NULL;
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v->nlacons = 0;
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v->spaceused = 0;
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re->re_magic = REMAGIC;
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re->re_info = 0; /* bits get set during parse */
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re->re_csize = sizeof(chr);
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re->re_collation = collation;
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re->re_guts = NULL;
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re->re_fns = VS(&functions);
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/* more complex setup, malloced things */
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re->re_guts = VS(MALLOC(sizeof(struct guts)));
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if (re->re_guts == NULL)
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return freev(v, REG_ESPACE);
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g = (struct guts *) re->re_guts;
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g->tree = NULL;
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initcm(v, &g->cmap);
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v->cm = &g->cmap;
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g->lacons = NULL;
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g->nlacons = 0;
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ZAPCNFA(g->search);
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v->nfa = newnfa(v, v->cm, (struct nfa *) NULL);
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CNOERR();
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/* set up a reasonably-sized transient cvec for getcvec usage */
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v->cv = newcvec(100, 20);
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if (v->cv == NULL)
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return freev(v, REG_ESPACE);
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/* parsing */
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lexstart(v); /* also handles prefixes */
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if ((v->cflags & REG_NLSTOP) || (v->cflags & REG_NLANCH))
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{
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/* assign newline a unique color */
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v->nlcolor = subcolor(v->cm, newline());
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okcolors(v->nfa, v->cm);
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}
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CNOERR();
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v->tree = parse(v, EOS, PLAIN, v->nfa->init, v->nfa->final);
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assert(SEE(EOS)); /* even if error; ISERR() => SEE(EOS) */
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CNOERR();
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assert(v->tree != NULL);
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/* finish setup of nfa and its subre tree */
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specialcolors(v->nfa);
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CNOERR();
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#ifdef REG_DEBUG
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if (debug != NULL)
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{
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fprintf(debug, "\n\n\n========= RAW ==========\n");
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dumpnfa(v->nfa, debug);
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dumpst(v->tree, debug, 1);
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}
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#endif
|
|
optst(v, v->tree);
|
|
v->ntree = numst(v->tree, 1);
|
|
markst(v->tree);
|
|
cleanst(v);
|
|
#ifdef REG_DEBUG
|
|
if (debug != NULL)
|
|
{
|
|
fprintf(debug, "\n\n\n========= TREE FIXED ==========\n");
|
|
dumpst(v->tree, debug, 1);
|
|
}
|
|
#endif
|
|
|
|
/* build compacted NFAs for tree and lacons */
|
|
re->re_info |= nfatree(v, v->tree, debug);
|
|
CNOERR();
|
|
assert(v->nlacons == 0 || v->lacons != NULL);
|
|
for (i = 1; i < v->nlacons; i++)
|
|
{
|
|
struct subre *lasub = &v->lacons[i];
|
|
|
|
#ifdef REG_DEBUG
|
|
if (debug != NULL)
|
|
fprintf(debug, "\n\n\n========= LA%d ==========\n", i);
|
|
#endif
|
|
|
|
/* Prepend .* to pattern if it's a lookbehind LACON */
|
|
nfanode(v, lasub, !LATYPE_IS_AHEAD(lasub->subno), debug);
|
|
}
|
|
CNOERR();
|
|
if (v->tree->flags & SHORTER)
|
|
NOTE(REG_USHORTEST);
|
|
|
|
/* build compacted NFAs for tree, lacons, fast search */
|
|
#ifdef REG_DEBUG
|
|
if (debug != NULL)
|
|
fprintf(debug, "\n\n\n========= SEARCH ==========\n");
|
|
#endif
|
|
/* can sacrifice main NFA now, so use it as work area */
|
|
(DISCARD) optimize(v->nfa, debug);
|
|
CNOERR();
|
|
makesearch(v, v->nfa);
|
|
CNOERR();
|
|
compact(v->nfa, &g->search);
|
|
CNOERR();
|
|
|
|
/* looks okay, package it up */
|
|
re->re_nsub = v->nsubexp;
|
|
v->re = NULL; /* freev no longer frees re */
|
|
g->magic = GUTSMAGIC;
|
|
g->cflags = v->cflags;
|
|
g->info = re->re_info;
|
|
g->nsub = re->re_nsub;
|
|
g->tree = v->tree;
|
|
v->tree = NULL;
|
|
g->ntree = v->ntree;
|
|
g->compare = (v->cflags & REG_ICASE) ? casecmp : cmp;
|
|
g->lacons = v->lacons;
|
|
v->lacons = NULL;
|
|
g->nlacons = v->nlacons;
|
|
|
|
#ifdef REG_DEBUG
|
|
if (flags & REG_DUMP)
|
|
dump(re, stdout);
|
|
#endif
|
|
|
|
assert(v->err == 0);
|
|
return freev(v, 0);
|
|
}
|
|
|
|
/*
|
|
* moresubs - enlarge subRE vector
|
|
*/
|
|
static void
|
|
moresubs(struct vars * v,
|
|
int wanted) /* want enough room for this one */
|
|
{
|
|
struct subre **p;
|
|
size_t n;
|
|
|
|
assert(wanted > 0 && (size_t) wanted >= v->nsubs);
|
|
n = (size_t) wanted *3 / 2 + 1;
|
|
|
|
if (v->subs == v->sub10)
|
|
{
|
|
p = (struct subre **) MALLOC(n * sizeof(struct subre *));
|
|
if (p != NULL)
|
|
memcpy(VS(p), VS(v->subs),
|
|
v->nsubs * sizeof(struct subre *));
|
|
}
|
|
else
|
|
p = (struct subre **) REALLOC(v->subs, n * sizeof(struct subre *));
|
|
if (p == NULL)
|
|
{
|
|
ERR(REG_ESPACE);
|
|
return;
|
|
}
|
|
v->subs = p;
|
|
for (p = &v->subs[v->nsubs]; v->nsubs < n; p++, v->nsubs++)
|
|
*p = NULL;
|
|
assert(v->nsubs == n);
|
|
assert((size_t) wanted < v->nsubs);
|
|
}
|
|
|
|
/*
|
|
* freev - free vars struct's substructures where necessary
|
|
*
|
|
* Optionally does error-number setting, and always returns error code
|
|
* (if any), to make error-handling code terser.
|
|
*/
|
|
static int
|
|
freev(struct vars * v,
|
|
int err)
|
|
{
|
|
if (v->re != NULL)
|
|
rfree(v->re);
|
|
if (v->subs != v->sub10)
|
|
FREE(v->subs);
|
|
if (v->nfa != NULL)
|
|
freenfa(v->nfa);
|
|
if (v->tree != NULL)
|
|
freesubre(v, v->tree);
|
|
if (v->treechain != NULL)
|
|
cleanst(v);
|
|
if (v->cv != NULL)
|
|
freecvec(v->cv);
|
|
if (v->cv2 != NULL)
|
|
freecvec(v->cv2);
|
|
if (v->lacons != NULL)
|
|
freelacons(v->lacons, v->nlacons);
|
|
ERR(err); /* nop if err==0 */
|
|
|
|
return v->err;
|
|
}
|
|
|
|
/*
|
|
* makesearch - turn an NFA into a search NFA (implicit prepend of .*?)
|
|
* NFA must have been optimize()d already.
|
|
*/
|
|
static void
|
|
makesearch(struct vars * v,
|
|
struct nfa * nfa)
|
|
{
|
|
struct arc *a;
|
|
struct arc *b;
|
|
struct state *pre = nfa->pre;
|
|
struct state *s;
|
|
struct state *s2;
|
|
struct state *slist;
|
|
|
|
/* no loops are needed if it's anchored */
|
|
for (a = pre->outs; a != NULL; a = a->outchain)
|
|
{
|
|
assert(a->type == PLAIN);
|
|
if (a->co != nfa->bos[0] && a->co != nfa->bos[1])
|
|
break;
|
|
}
|
|
if (a != NULL)
|
|
{
|
|
/* add implicit .* in front */
|
|
rainbow(nfa, v->cm, PLAIN, COLORLESS, pre, pre);
|
|
|
|
/* and ^* and \A* too -- not always necessary, but harmless */
|
|
newarc(nfa, PLAIN, nfa->bos[0], pre, pre);
|
|
newarc(nfa, PLAIN, nfa->bos[1], pre, pre);
|
|
}
|
|
|
|
/*
|
|
* Now here's the subtle part. Because many REs have no lookback
|
|
* constraints, often knowing when you were in the pre state tells you
|
|
* little; it's the next state(s) that are informative. But some of them
|
|
* may have other inarcs, i.e. it may be possible to make actual progress
|
|
* and then return to one of them. We must de-optimize such cases,
|
|
* splitting each such state into progress and no-progress states.
|
|
*/
|
|
|
|
/* first, make a list of the states reachable from pre and elsewhere */
|
|
slist = NULL;
|
|
for (a = pre->outs; a != NULL; a = a->outchain)
|
|
{
|
|
s = a->to;
|
|
for (b = s->ins; b != NULL; b = b->inchain)
|
|
{
|
|
if (b->from != pre)
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* We want to mark states as being in the list already by having non
|
|
* NULL tmp fields, but we can't just store the old slist value in tmp
|
|
* because that doesn't work for the first such state. Instead, the
|
|
* first list entry gets its own address in tmp.
|
|
*/
|
|
if (b != NULL && s->tmp == NULL)
|
|
{
|
|
s->tmp = (slist != NULL) ? slist : s;
|
|
slist = s;
|
|
}
|
|
}
|
|
|
|
/* do the splits */
|
|
for (s = slist; s != NULL; s = s2)
|
|
{
|
|
s2 = newstate(nfa);
|
|
NOERR();
|
|
copyouts(nfa, s, s2);
|
|
NOERR();
|
|
for (a = s->ins; a != NULL; a = b)
|
|
{
|
|
b = a->inchain;
|
|
if (a->from != pre)
|
|
{
|
|
cparc(nfa, a, a->from, s2);
|
|
freearc(nfa, a);
|
|
}
|
|
}
|
|
s2 = (s->tmp != s) ? s->tmp : NULL;
|
|
s->tmp = NULL; /* clean up while we're at it */
|
|
}
|
|
}
|
|
|
|
/*
|
|
* parse - parse an RE
|
|
*
|
|
* This is actually just the top level, which parses a bunch of branches
|
|
* tied together with '|'. They appear in the tree as the left children
|
|
* of a chain of '|' subres.
|
|
*/
|
|
static struct subre *
|
|
parse(struct vars * v,
|
|
int stopper, /* EOS or ')' */
|
|
int type, /* LACON (lookaround subRE) or PLAIN */
|
|
struct state * init, /* initial state */
|
|
struct state * final) /* final state */
|
|
{
|
|
struct state *left; /* scaffolding for branch */
|
|
struct state *right;
|
|
struct subre *branches; /* top level */
|
|
struct subre *branch; /* current branch */
|
|
struct subre *t; /* temporary */
|
|
int firstbranch; /* is this the first branch? */
|
|
|
|
assert(stopper == ')' || stopper == EOS);
|
|
|
|
branches = subre(v, '|', LONGER, init, final);
|
|
NOERRN();
|
|
branch = branches;
|
|
firstbranch = 1;
|
|
do
|
|
{ /* a branch */
|
|
if (!firstbranch)
|
|
{
|
|
/* need a place to hang it */
|
|
branch->right = subre(v, '|', LONGER, init, final);
|
|
NOERRN();
|
|
branch = branch->right;
|
|
}
|
|
firstbranch = 0;
|
|
left = newstate(v->nfa);
|
|
right = newstate(v->nfa);
|
|
NOERRN();
|
|
EMPTYARC(init, left);
|
|
EMPTYARC(right, final);
|
|
NOERRN();
|
|
branch->left = parsebranch(v, stopper, type, left, right, 0);
|
|
NOERRN();
|
|
branch->flags |= UP(branch->flags | branch->left->flags);
|
|
if ((branch->flags & ~branches->flags) != 0) /* new flags */
|
|
for (t = branches; t != branch; t = t->right)
|
|
t->flags |= branch->flags;
|
|
} while (EAT('|'));
|
|
assert(SEE(stopper) || SEE(EOS));
|
|
|
|
if (!SEE(stopper))
|
|
{
|
|
assert(stopper == ')' && SEE(EOS));
|
|
ERR(REG_EPAREN);
|
|
}
|
|
|
|
/* optimize out simple cases */
|
|
if (branch == branches)
|
|
{ /* only one branch */
|
|
assert(branch->right == NULL);
|
|
t = branch->left;
|
|
branch->left = NULL;
|
|
freesubre(v, branches);
|
|
branches = t;
|
|
}
|
|
else if (!MESSY(branches->flags))
|
|
{ /* no interesting innards */
|
|
freesubre(v, branches->left);
|
|
branches->left = NULL;
|
|
freesubre(v, branches->right);
|
|
branches->right = NULL;
|
|
branches->op = '=';
|
|
}
|
|
|
|
return branches;
|
|
}
|
|
|
|
/*
|
|
* parsebranch - parse one branch of an RE
|
|
*
|
|
* This mostly manages concatenation, working closely with parseqatom().
|
|
* Concatenated things are bundled up as much as possible, with separate
|
|
* ',' nodes introduced only when necessary due to substructure.
|
|
*/
|
|
static struct subre *
|
|
parsebranch(struct vars * v,
|
|
int stopper, /* EOS or ')' */
|
|
int type, /* LACON (lookaround subRE) or PLAIN */
|
|
struct state * left, /* leftmost state */
|
|
struct state * right, /* rightmost state */
|
|
int partial) /* is this only part of a branch? */
|
|
{
|
|
struct state *lp; /* left end of current construct */
|
|
int seencontent; /* is there anything in this branch yet? */
|
|
struct subre *t;
|
|
|
|
lp = left;
|
|
seencontent = 0;
|
|
t = subre(v, '=', 0, left, right); /* op '=' is tentative */
|
|
NOERRN();
|
|
while (!SEE('|') && !SEE(stopper) && !SEE(EOS))
|
|
{
|
|
if (seencontent)
|
|
{ /* implicit concat operator */
|
|
lp = newstate(v->nfa);
|
|
NOERRN();
|
|
moveins(v->nfa, right, lp);
|
|
}
|
|
seencontent = 1;
|
|
|
|
/* NB, recursion in parseqatom() may swallow rest of branch */
|
|
parseqatom(v, stopper, type, lp, right, t);
|
|
NOERRN();
|
|
}
|
|
|
|
if (!seencontent)
|
|
{ /* empty branch */
|
|
if (!partial)
|
|
NOTE(REG_UUNSPEC);
|
|
assert(lp == left);
|
|
EMPTYARC(left, right);
|
|
}
|
|
|
|
return t;
|
|
}
|
|
|
|
/*
|
|
* parseqatom - parse one quantified atom or constraint of an RE
|
|
*
|
|
* The bookkeeping near the end cooperates very closely with parsebranch();
|
|
* in particular, it contains a recursion that can involve parsing the rest
|
|
* of the branch, making this function's name somewhat inaccurate.
|
|
*/
|
|
static void
|
|
parseqatom(struct vars * v,
|
|
int stopper, /* EOS or ')' */
|
|
int type, /* LACON (lookaround subRE) or PLAIN */
|
|
struct state * lp, /* left state to hang it on */
|
|
struct state * rp, /* right state to hang it on */
|
|
struct subre * top) /* subtree top */
|
|
{
|
|
struct state *s; /* temporaries for new states */
|
|
struct state *s2;
|
|
|
|
#define ARCV(t, val) newarc(v->nfa, t, val, lp, rp)
|
|
int m,
|
|
n;
|
|
struct subre *atom; /* atom's subtree */
|
|
struct subre *t;
|
|
int cap; /* capturing parens? */
|
|
int latype; /* lookaround constraint type */
|
|
int subno; /* capturing-parens or backref number */
|
|
int atomtype;
|
|
int qprefer; /* quantifier short/long preference */
|
|
int f;
|
|
struct subre **atomp; /* where the pointer to atom is */
|
|
|
|
/* initial bookkeeping */
|
|
atom = NULL;
|
|
assert(lp->nouts == 0); /* must string new code */
|
|
assert(rp->nins == 0); /* between lp and rp */
|
|
subno = 0; /* just to shut lint up */
|
|
|
|
/* an atom or constraint... */
|
|
atomtype = v->nexttype;
|
|
switch (atomtype)
|
|
{
|
|
/* first, constraints, which end by returning */
|
|
case '^':
|
|
ARCV('^', 1);
|
|
if (v->cflags & REG_NLANCH)
|
|
ARCV(BEHIND, v->nlcolor);
|
|
NEXT();
|
|
return;
|
|
break;
|
|
case '$':
|
|
ARCV('$', 1);
|
|
if (v->cflags & REG_NLANCH)
|
|
ARCV(AHEAD, v->nlcolor);
|
|
NEXT();
|
|
return;
|
|
break;
|
|
case SBEGIN:
|
|
ARCV('^', 1); /* BOL */
|
|
ARCV('^', 0); /* or BOS */
|
|
NEXT();
|
|
return;
|
|
break;
|
|
case SEND:
|
|
ARCV('$', 1); /* EOL */
|
|
ARCV('$', 0); /* or EOS */
|
|
NEXT();
|
|
return;
|
|
break;
|
|
case '<':
|
|
wordchrs(v); /* does NEXT() */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
nonword(v, BEHIND, lp, s);
|
|
word(v, AHEAD, s, rp);
|
|
return;
|
|
break;
|
|
case '>':
|
|
wordchrs(v); /* does NEXT() */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
word(v, BEHIND, lp, s);
|
|
nonword(v, AHEAD, s, rp);
|
|
return;
|
|
break;
|
|
case WBDRY:
|
|
wordchrs(v); /* does NEXT() */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
nonword(v, BEHIND, lp, s);
|
|
word(v, AHEAD, s, rp);
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
word(v, BEHIND, lp, s);
|
|
nonword(v, AHEAD, s, rp);
|
|
return;
|
|
break;
|
|
case NWBDRY:
|
|
wordchrs(v); /* does NEXT() */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
word(v, BEHIND, lp, s);
|
|
word(v, AHEAD, s, rp);
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
nonword(v, BEHIND, lp, s);
|
|
nonword(v, AHEAD, s, rp);
|
|
return;
|
|
break;
|
|
case LACON: /* lookaround constraint */
|
|
latype = v->nextvalue;
|
|
NEXT();
|
|
s = newstate(v->nfa);
|
|
s2 = newstate(v->nfa);
|
|
NOERR();
|
|
t = parse(v, ')', LACON, s, s2);
|
|
freesubre(v, t); /* internal structure irrelevant */
|
|
NOERR();
|
|
assert(SEE(')'));
|
|
NEXT();
|
|
processlacon(v, s, s2, latype, lp, rp);
|
|
return;
|
|
break;
|
|
/* then errors, to get them out of the way */
|
|
case '*':
|
|
case '+':
|
|
case '?':
|
|
case '{':
|
|
ERR(REG_BADRPT);
|
|
return;
|
|
break;
|
|
default:
|
|
ERR(REG_ASSERT);
|
|
return;
|
|
break;
|
|
/* then plain characters, and minor variants on that theme */
|
|
case ')': /* unbalanced paren */
|
|
if ((v->cflags & REG_ADVANCED) != REG_EXTENDED)
|
|
{
|
|
ERR(REG_EPAREN);
|
|
return;
|
|
}
|
|
/* legal in EREs due to specification botch */
|
|
NOTE(REG_UPBOTCH);
|
|
/* fallthrough into case PLAIN */
|
|
case PLAIN:
|
|
onechr(v, v->nextvalue, lp, rp);
|
|
okcolors(v->nfa, v->cm);
|
|
NOERR();
|
|
NEXT();
|
|
break;
|
|
case '[':
|
|
if (v->nextvalue == 1)
|
|
bracket(v, lp, rp);
|
|
else
|
|
cbracket(v, lp, rp);
|
|
assert(SEE(']') || ISERR());
|
|
NEXT();
|
|
break;
|
|
case '.':
|
|
rainbow(v->nfa, v->cm, PLAIN,
|
|
(v->cflags & REG_NLSTOP) ? v->nlcolor : COLORLESS,
|
|
lp, rp);
|
|
NEXT();
|
|
break;
|
|
/* and finally the ugly stuff */
|
|
case '(': /* value flags as capturing or non */
|
|
cap = (type == LACON) ? 0 : v->nextvalue;
|
|
if (cap)
|
|
{
|
|
v->nsubexp++;
|
|
subno = v->nsubexp;
|
|
if ((size_t) subno >= v->nsubs)
|
|
moresubs(v, subno);
|
|
assert((size_t) subno < v->nsubs);
|
|
}
|
|
else
|
|
atomtype = PLAIN; /* something that's not '(' */
|
|
NEXT();
|
|
/* need new endpoints because tree will contain pointers */
|
|
s = newstate(v->nfa);
|
|
s2 = newstate(v->nfa);
|
|
NOERR();
|
|
EMPTYARC(lp, s);
|
|
EMPTYARC(s2, rp);
|
|
NOERR();
|
|
atom = parse(v, ')', type, s, s2);
|
|
assert(SEE(')') || ISERR());
|
|
NEXT();
|
|
NOERR();
|
|
if (cap)
|
|
{
|
|
v->subs[subno] = atom;
|
|
t = subre(v, '(', atom->flags | CAP, lp, rp);
|
|
NOERR();
|
|
t->subno = subno;
|
|
t->left = atom;
|
|
atom = t;
|
|
}
|
|
/* postpone everything else pending possible {0} */
|
|
break;
|
|
case BACKREF: /* the Feature From The Black Lagoon */
|
|
INSIST(type != LACON, REG_ESUBREG);
|
|
INSIST(v->nextvalue < v->nsubs, REG_ESUBREG);
|
|
INSIST(v->subs[v->nextvalue] != NULL, REG_ESUBREG);
|
|
NOERR();
|
|
assert(v->nextvalue > 0);
|
|
atom = subre(v, 'b', BACKR, lp, rp);
|
|
NOERR();
|
|
subno = v->nextvalue;
|
|
atom->subno = subno;
|
|
EMPTYARC(lp, rp); /* temporarily, so there's something */
|
|
NEXT();
|
|
break;
|
|
}
|
|
|
|
/* ...and an atom may be followed by a quantifier */
|
|
switch (v->nexttype)
|
|
{
|
|
case '*':
|
|
m = 0;
|
|
n = DUPINF;
|
|
qprefer = (v->nextvalue) ? LONGER : SHORTER;
|
|
NEXT();
|
|
break;
|
|
case '+':
|
|
m = 1;
|
|
n = DUPINF;
|
|
qprefer = (v->nextvalue) ? LONGER : SHORTER;
|
|
NEXT();
|
|
break;
|
|
case '?':
|
|
m = 0;
|
|
n = 1;
|
|
qprefer = (v->nextvalue) ? LONGER : SHORTER;
|
|
NEXT();
|
|
break;
|
|
case '{':
|
|
NEXT();
|
|
m = scannum(v);
|
|
if (EAT(','))
|
|
{
|
|
if (SEE(DIGIT))
|
|
n = scannum(v);
|
|
else
|
|
n = DUPINF;
|
|
if (m > n)
|
|
{
|
|
ERR(REG_BADBR);
|
|
return;
|
|
}
|
|
/* {m,n} exercises preference, even if it's {m,m} */
|
|
qprefer = (v->nextvalue) ? LONGER : SHORTER;
|
|
}
|
|
else
|
|
{
|
|
n = m;
|
|
/* {m} passes operand's preference through */
|
|
qprefer = 0;
|
|
}
|
|
if (!SEE('}'))
|
|
{ /* catches errors too */
|
|
ERR(REG_BADBR);
|
|
return;
|
|
}
|
|
NEXT();
|
|
break;
|
|
default: /* no quantifier */
|
|
m = n = 1;
|
|
qprefer = 0;
|
|
break;
|
|
}
|
|
|
|
/* annoying special case: {0} or {0,0} cancels everything */
|
|
if (m == 0 && n == 0)
|
|
{
|
|
if (atom != NULL)
|
|
freesubre(v, atom);
|
|
if (atomtype == '(')
|
|
v->subs[subno] = NULL;
|
|
delsub(v->nfa, lp, rp);
|
|
EMPTYARC(lp, rp);
|
|
return;
|
|
}
|
|
|
|
/* if not a messy case, avoid hard part */
|
|
assert(!MESSY(top->flags));
|
|
f = top->flags | qprefer | ((atom != NULL) ? atom->flags : 0);
|
|
if (atomtype != '(' && atomtype != BACKREF && !MESSY(UP(f)))
|
|
{
|
|
if (!(m == 1 && n == 1))
|
|
repeat(v, lp, rp, m, n);
|
|
if (atom != NULL)
|
|
freesubre(v, atom);
|
|
top->flags = f;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* hard part: something messy
|
|
*
|
|
* That is, capturing parens, back reference, short/long clash, or an atom
|
|
* with substructure containing one of those.
|
|
*/
|
|
|
|
/* now we'll need a subre for the contents even if they're boring */
|
|
if (atom == NULL)
|
|
{
|
|
atom = subre(v, '=', 0, lp, rp);
|
|
NOERR();
|
|
}
|
|
|
|
/*----------
|
|
* Prepare a general-purpose state skeleton.
|
|
*
|
|
* In the no-backrefs case, we want this:
|
|
*
|
|
* [lp] ---> [s] ---prefix---> [begin] ---atom---> [end] ---rest---> [rp]
|
|
*
|
|
* where prefix is some repetitions of atom. In the general case we need
|
|
*
|
|
* [lp] ---> [s] ---iterator---> [s2] ---rest---> [rp]
|
|
*
|
|
* where the iterator wraps around [begin] ---atom---> [end]
|
|
*
|
|
* We make the s state here for both cases; s2 is made below if needed
|
|
*----------
|
|
*/
|
|
s = newstate(v->nfa); /* first, new endpoints for the atom */
|
|
s2 = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, lp, s);
|
|
moveins(v->nfa, rp, s2);
|
|
NOERR();
|
|
atom->begin = s;
|
|
atom->end = s2;
|
|
s = newstate(v->nfa); /* set up starting state */
|
|
NOERR();
|
|
EMPTYARC(lp, s);
|
|
NOERR();
|
|
|
|
/* break remaining subRE into x{...} and what follows */
|
|
t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp);
|
|
NOERR();
|
|
t->left = atom;
|
|
atomp = &t->left;
|
|
|
|
/* here we should recurse... but we must postpone that to the end */
|
|
|
|
/* split top into prefix and remaining */
|
|
assert(top->op == '=' && top->left == NULL && top->right == NULL);
|
|
top->left = subre(v, '=', top->flags, top->begin, lp);
|
|
NOERR();
|
|
top->op = '.';
|
|
top->right = t;
|
|
|
|
/* if it's a backref, now is the time to replicate the subNFA */
|
|
if (atomtype == BACKREF)
|
|
{
|
|
assert(atom->begin->nouts == 1); /* just the EMPTY */
|
|
delsub(v->nfa, atom->begin, atom->end);
|
|
assert(v->subs[subno] != NULL);
|
|
|
|
/*
|
|
* And here's why the recursion got postponed: it must wait until the
|
|
* skeleton is filled in, because it may hit a backref that wants to
|
|
* copy the filled-in skeleton.
|
|
*/
|
|
dupnfa(v->nfa, v->subs[subno]->begin, v->subs[subno]->end,
|
|
atom->begin, atom->end);
|
|
NOERR();
|
|
}
|
|
|
|
/*
|
|
* It's quantifier time. If the atom is just a backref, we'll let it deal
|
|
* with quantifiers internally.
|
|
*/
|
|
if (atomtype == BACKREF)
|
|
{
|
|
/* special case: backrefs have internal quantifiers */
|
|
EMPTYARC(s, atom->begin); /* empty prefix */
|
|
/* just stuff everything into atom */
|
|
repeat(v, atom->begin, atom->end, m, n);
|
|
atom->min = (short) m;
|
|
atom->max = (short) n;
|
|
atom->flags |= COMBINE(qprefer, atom->flags);
|
|
/* rest of branch can be strung starting from atom->end */
|
|
s2 = atom->end;
|
|
}
|
|
else if (m == 1 && n == 1)
|
|
{
|
|
/* no/vacuous quantifier: done */
|
|
EMPTYARC(s, atom->begin); /* empty prefix */
|
|
/* rest of branch can be strung starting from atom->end */
|
|
s2 = atom->end;
|
|
}
|
|
else if (m > 0 && !(atom->flags & BACKR))
|
|
{
|
|
/*
|
|
* If there's no backrefs involved, we can turn x{m,n} into
|
|
* x{m-1,n-1}x, with capturing parens in only the second x. This is
|
|
* valid because we only care about capturing matches from the final
|
|
* iteration of the quantifier. It's a win because we can implement
|
|
* the backref-free left side as a plain DFA node, since we don't
|
|
* really care where its submatches are.
|
|
*/
|
|
dupnfa(v->nfa, atom->begin, atom->end, s, atom->begin);
|
|
assert(m >= 1 && m != DUPINF && n >= 1);
|
|
repeat(v, s, atom->begin, m - 1, (n == DUPINF) ? n : n - 1);
|
|
f = COMBINE(qprefer, atom->flags);
|
|
t = subre(v, '.', f, s, atom->end); /* prefix and atom */
|
|
NOERR();
|
|
t->left = subre(v, '=', PREF(f), s, atom->begin);
|
|
NOERR();
|
|
t->right = atom;
|
|
*atomp = t;
|
|
/* rest of branch can be strung starting from atom->end */
|
|
s2 = atom->end;
|
|
}
|
|
else
|
|
{
|
|
/* general case: need an iteration node */
|
|
s2 = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, atom->end, s2);
|
|
NOERR();
|
|
dupnfa(v->nfa, atom->begin, atom->end, s, s2);
|
|
repeat(v, s, s2, m, n);
|
|
f = COMBINE(qprefer, atom->flags);
|
|
t = subre(v, '*', f, s, s2);
|
|
NOERR();
|
|
t->min = (short) m;
|
|
t->max = (short) n;
|
|
t->left = atom;
|
|
*atomp = t;
|
|
/* rest of branch is to be strung from iteration's end state */
|
|
}
|
|
|
|
/* and finally, look after that postponed recursion */
|
|
t = top->right;
|
|
if (!(SEE('|') || SEE(stopper) || SEE(EOS)))
|
|
t->right = parsebranch(v, stopper, type, s2, rp, 1);
|
|
else
|
|
{
|
|
EMPTYARC(s2, rp);
|
|
t->right = subre(v, '=', 0, s2, rp);
|
|
}
|
|
NOERR();
|
|
assert(SEE('|') || SEE(stopper) || SEE(EOS));
|
|
t->flags |= COMBINE(t->flags, t->right->flags);
|
|
top->flags |= COMBINE(top->flags, t->flags);
|
|
}
|
|
|
|
/*
|
|
* nonword - generate arcs for non-word-character ahead or behind
|
|
*/
|
|
static void
|
|
nonword(struct vars * v,
|
|
int dir, /* AHEAD or BEHIND */
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
int anchor = (dir == AHEAD) ? '$' : '^';
|
|
|
|
assert(dir == AHEAD || dir == BEHIND);
|
|
newarc(v->nfa, anchor, 1, lp, rp);
|
|
newarc(v->nfa, anchor, 0, lp, rp);
|
|
colorcomplement(v->nfa, v->cm, dir, v->wordchrs, lp, rp);
|
|
/* (no need for special attention to \n) */
|
|
}
|
|
|
|
/*
|
|
* word - generate arcs for word character ahead or behind
|
|
*/
|
|
static void
|
|
word(struct vars * v,
|
|
int dir, /* AHEAD or BEHIND */
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
assert(dir == AHEAD || dir == BEHIND);
|
|
cloneouts(v->nfa, v->wordchrs, lp, rp, dir);
|
|
/* (no need for special attention to \n) */
|
|
}
|
|
|
|
/*
|
|
* scannum - scan a number
|
|
*/
|
|
static int /* value, <= DUPMAX */
|
|
scannum(struct vars * v)
|
|
{
|
|
int n = 0;
|
|
|
|
while (SEE(DIGIT) && n < DUPMAX)
|
|
{
|
|
n = n * 10 + v->nextvalue;
|
|
NEXT();
|
|
}
|
|
if (SEE(DIGIT) || n > DUPMAX)
|
|
{
|
|
ERR(REG_BADBR);
|
|
return 0;
|
|
}
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* repeat - replicate subNFA for quantifiers
|
|
*
|
|
* The sub-NFA strung from lp to rp is modified to represent m to n
|
|
* repetitions of its initial contents.
|
|
*
|
|
* The duplication sequences used here are chosen carefully so that any
|
|
* pointers starting out pointing into the subexpression end up pointing into
|
|
* the last occurrence. (Note that it may not be strung between the same
|
|
* left and right end states, however!) This used to be important for the
|
|
* subRE tree, although the important bits are now handled by the in-line
|
|
* code in parse(), and when this is called, it doesn't matter any more.
|
|
*/
|
|
static void
|
|
repeat(struct vars * v,
|
|
struct state * lp,
|
|
struct state * rp,
|
|
int m,
|
|
int n)
|
|
{
|
|
#define SOME 2
|
|
#define INF 3
|
|
#define PAIR(x, y) ((x)*4 + (y))
|
|
#define REDUCE(x) ( ((x) == DUPINF) ? INF : (((x) > 1) ? SOME : (x)) )
|
|
const int rm = REDUCE(m);
|
|
const int rn = REDUCE(n);
|
|
struct state *s;
|
|
struct state *s2;
|
|
|
|
switch (PAIR(rm, rn))
|
|
{
|
|
case PAIR(0, 0): /* empty string */
|
|
delsub(v->nfa, lp, rp);
|
|
EMPTYARC(lp, rp);
|
|
break;
|
|
case PAIR(0, 1): /* do as x| */
|
|
EMPTYARC(lp, rp);
|
|
break;
|
|
case PAIR(0, SOME): /* do as x{1,n}| */
|
|
repeat(v, lp, rp, 1, n);
|
|
NOERR();
|
|
EMPTYARC(lp, rp);
|
|
break;
|
|
case PAIR(0, INF): /* loop x around */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, lp, s);
|
|
moveins(v->nfa, rp, s);
|
|
EMPTYARC(lp, s);
|
|
EMPTYARC(s, rp);
|
|
break;
|
|
case PAIR(1, 1): /* no action required */
|
|
break;
|
|
case PAIR(1, SOME): /* do as x{0,n-1}x = (x{1,n-1}|)x */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, lp, s);
|
|
dupnfa(v->nfa, s, rp, lp, s);
|
|
NOERR();
|
|
repeat(v, lp, s, 1, n - 1);
|
|
NOERR();
|
|
EMPTYARC(lp, s);
|
|
break;
|
|
case PAIR(1, INF): /* add loopback arc */
|
|
s = newstate(v->nfa);
|
|
s2 = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, lp, s);
|
|
moveins(v->nfa, rp, s2);
|
|
EMPTYARC(lp, s);
|
|
EMPTYARC(s2, rp);
|
|
EMPTYARC(s2, s);
|
|
break;
|
|
case PAIR(SOME, SOME): /* do as x{m-1,n-1}x */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, lp, s);
|
|
dupnfa(v->nfa, s, rp, lp, s);
|
|
NOERR();
|
|
repeat(v, lp, s, m - 1, n - 1);
|
|
break;
|
|
case PAIR(SOME, INF): /* do as x{m-1,}x */
|
|
s = newstate(v->nfa);
|
|
NOERR();
|
|
moveouts(v->nfa, lp, s);
|
|
dupnfa(v->nfa, s, rp, lp, s);
|
|
NOERR();
|
|
repeat(v, lp, s, m - 1, n);
|
|
break;
|
|
default:
|
|
ERR(REG_ASSERT);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* bracket - handle non-complemented bracket expression
|
|
* Also called from cbracket for complemented bracket expressions.
|
|
*/
|
|
static void
|
|
bracket(struct vars * v,
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
assert(SEE('['));
|
|
NEXT();
|
|
while (!SEE(']') && !SEE(EOS))
|
|
brackpart(v, lp, rp);
|
|
assert(SEE(']') || ISERR());
|
|
okcolors(v->nfa, v->cm);
|
|
}
|
|
|
|
/*
|
|
* cbracket - handle complemented bracket expression
|
|
* We do it by calling bracket() with dummy endpoints, and then complementing
|
|
* the result. The alternative would be to invoke rainbow(), and then delete
|
|
* arcs as the b.e. is seen... but that gets messy.
|
|
*/
|
|
static void
|
|
cbracket(struct vars * v,
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
struct state *left = newstate(v->nfa);
|
|
struct state *right = newstate(v->nfa);
|
|
|
|
NOERR();
|
|
bracket(v, left, right);
|
|
if (v->cflags & REG_NLSTOP)
|
|
newarc(v->nfa, PLAIN, v->nlcolor, left, right);
|
|
NOERR();
|
|
|
|
assert(lp->nouts == 0); /* all outarcs will be ours */
|
|
|
|
/*
|
|
* Easy part of complementing, and all there is to do since the MCCE code
|
|
* was removed.
|
|
*/
|
|
colorcomplement(v->nfa, v->cm, PLAIN, left, lp, rp);
|
|
NOERR();
|
|
dropstate(v->nfa, left);
|
|
assert(right->nins == 0);
|
|
freestate(v->nfa, right);
|
|
}
|
|
|
|
/*
|
|
* brackpart - handle one item (or range) within a bracket expression
|
|
*/
|
|
static void
|
|
brackpart(struct vars * v,
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
celt startc;
|
|
celt endc;
|
|
struct cvec *cv;
|
|
const chr *startp;
|
|
const chr *endp;
|
|
chr c[1];
|
|
|
|
/* parse something, get rid of special cases, take shortcuts */
|
|
switch (v->nexttype)
|
|
{
|
|
case RANGE: /* a-b-c or other botch */
|
|
ERR(REG_ERANGE);
|
|
return;
|
|
break;
|
|
case PLAIN:
|
|
c[0] = v->nextvalue;
|
|
NEXT();
|
|
/* shortcut for ordinary chr (not range) */
|
|
if (!SEE(RANGE))
|
|
{
|
|
onechr(v, c[0], lp, rp);
|
|
return;
|
|
}
|
|
startc = element(v, c, c + 1);
|
|
NOERR();
|
|
break;
|
|
case COLLEL:
|
|
startp = v->now;
|
|
endp = scanplain(v);
|
|
INSIST(startp < endp, REG_ECOLLATE);
|
|
NOERR();
|
|
startc = element(v, startp, endp);
|
|
NOERR();
|
|
break;
|
|
case ECLASS:
|
|
startp = v->now;
|
|
endp = scanplain(v);
|
|
INSIST(startp < endp, REG_ECOLLATE);
|
|
NOERR();
|
|
startc = element(v, startp, endp);
|
|
NOERR();
|
|
cv = eclass(v, startc, (v->cflags & REG_ICASE));
|
|
NOERR();
|
|
dovec(v, cv, lp, rp);
|
|
return;
|
|
break;
|
|
case CCLASS:
|
|
startp = v->now;
|
|
endp = scanplain(v);
|
|
INSIST(startp < endp, REG_ECTYPE);
|
|
NOERR();
|
|
cv = cclass(v, startp, endp, (v->cflags & REG_ICASE));
|
|
NOERR();
|
|
dovec(v, cv, lp, rp);
|
|
return;
|
|
break;
|
|
default:
|
|
ERR(REG_ASSERT);
|
|
return;
|
|
break;
|
|
}
|
|
|
|
if (SEE(RANGE))
|
|
{
|
|
NEXT();
|
|
switch (v->nexttype)
|
|
{
|
|
case PLAIN:
|
|
case RANGE:
|
|
c[0] = v->nextvalue;
|
|
NEXT();
|
|
endc = element(v, c, c + 1);
|
|
NOERR();
|
|
break;
|
|
case COLLEL:
|
|
startp = v->now;
|
|
endp = scanplain(v);
|
|
INSIST(startp < endp, REG_ECOLLATE);
|
|
NOERR();
|
|
endc = element(v, startp, endp);
|
|
NOERR();
|
|
break;
|
|
default:
|
|
ERR(REG_ERANGE);
|
|
return;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
endc = startc;
|
|
|
|
/*
|
|
* Ranges are unportable. Actually, standard C does guarantee that digits
|
|
* are contiguous, but making that an exception is just too complicated.
|
|
*/
|
|
if (startc != endc)
|
|
NOTE(REG_UUNPORT);
|
|
cv = range(v, startc, endc, (v->cflags & REG_ICASE));
|
|
NOERR();
|
|
dovec(v, cv, lp, rp);
|
|
}
|
|
|
|
/*
|
|
* scanplain - scan PLAIN contents of [. etc.
|
|
*
|
|
* Certain bits of trickery in lex.c know that this code does not try
|
|
* to look past the final bracket of the [. etc.
|
|
*/
|
|
static const chr * /* just after end of sequence */
|
|
scanplain(struct vars * v)
|
|
{
|
|
const chr *endp;
|
|
|
|
assert(SEE(COLLEL) || SEE(ECLASS) || SEE(CCLASS));
|
|
NEXT();
|
|
|
|
endp = v->now;
|
|
while (SEE(PLAIN))
|
|
{
|
|
endp = v->now;
|
|
NEXT();
|
|
}
|
|
|
|
assert(SEE(END) || ISERR());
|
|
NEXT();
|
|
|
|
return endp;
|
|
}
|
|
|
|
/*
|
|
* onechr - fill in arcs for a plain character, and possible case complements
|
|
* This is mostly a shortcut for efficient handling of the common case.
|
|
*/
|
|
static void
|
|
onechr(struct vars * v,
|
|
chr c,
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
if (!(v->cflags & REG_ICASE))
|
|
{
|
|
newarc(v->nfa, PLAIN, subcolor(v->cm, c), lp, rp);
|
|
return;
|
|
}
|
|
|
|
/* rats, need general case anyway... */
|
|
dovec(v, allcases(v, c), lp, rp);
|
|
}
|
|
|
|
/*
|
|
* dovec - fill in arcs for each element of a cvec
|
|
*/
|
|
static void
|
|
dovec(struct vars * v,
|
|
struct cvec * cv,
|
|
struct state * lp,
|
|
struct state * rp)
|
|
{
|
|
chr ch,
|
|
from,
|
|
to;
|
|
const chr *p;
|
|
int i;
|
|
|
|
/* ordinary characters */
|
|
for (p = cv->chrs, i = cv->nchrs; i > 0; p++, i--)
|
|
{
|
|
ch = *p;
|
|
newarc(v->nfa, PLAIN, subcolor(v->cm, ch), lp, rp);
|
|
}
|
|
|
|
/* and the ranges */
|
|
for (p = cv->ranges, i = cv->nranges; i > 0; p += 2, i--)
|
|
{
|
|
from = *p;
|
|
to = *(p + 1);
|
|
if (from <= to)
|
|
subrange(v, from, to, lp, rp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* wordchrs - set up word-chr list for word-boundary stuff, if needed
|
|
*
|
|
* The list is kept as a bunch of arcs between two dummy states; it's
|
|
* disposed of by the unreachable-states sweep in NFA optimization.
|
|
* Does NEXT(). Must not be called from any unusual lexical context.
|
|
* This should be reconciled with the \w etc. handling in lex.c, and
|
|
* should be cleaned up to reduce dependencies on input scanning.
|
|
*/
|
|
static void
|
|
wordchrs(struct vars * v)
|
|
{
|
|
struct state *left;
|
|
struct state *right;
|
|
|
|
if (v->wordchrs != NULL)
|
|
{
|
|
NEXT(); /* for consistency */
|
|
return;
|
|
}
|
|
|
|
left = newstate(v->nfa);
|
|
right = newstate(v->nfa);
|
|
NOERR();
|
|
/* fine point: implemented with [::], and lexer will set REG_ULOCALE */
|
|
lexword(v);
|
|
NEXT();
|
|
assert(v->savenow != NULL && SEE('['));
|
|
bracket(v, left, right);
|
|
assert((v->savenow != NULL && SEE(']')) || ISERR());
|
|
NEXT();
|
|
NOERR();
|
|
v->wordchrs = left;
|
|
}
|
|
|
|
/*
|
|
* processlacon - generate the NFA representation of a LACON
|
|
*
|
|
* In the general case this is just newlacon() + newarc(), but some cases
|
|
* can be optimized.
|
|
*/
|
|
static void
|
|
processlacon(struct vars * v,
|
|
struct state * begin, /* start of parsed LACON sub-re */
|
|
struct state * end, /* end of parsed LACON sub-re */
|
|
int latype,
|
|
struct state * lp, /* left state to hang it on */
|
|
struct state * rp) /* right state to hang it on */
|
|
{
|
|
struct state *s1;
|
|
int n;
|
|
|
|
/*
|
|
* Check for lookaround RE consisting of a single plain color arc (or set
|
|
* of arcs); this would typically be a simple chr or a bracket expression.
|
|
*/
|
|
s1 = single_color_transition(begin, end);
|
|
switch (latype)
|
|
{
|
|
case LATYPE_AHEAD_POS:
|
|
/* If lookahead RE is just colorset C, convert to AHEAD(C) */
|
|
if (s1 != NULL)
|
|
{
|
|
cloneouts(v->nfa, s1, lp, rp, AHEAD);
|
|
return;
|
|
}
|
|
break;
|
|
case LATYPE_AHEAD_NEG:
|
|
/* If lookahead RE is just colorset C, convert to AHEAD(^C)|$ */
|
|
if (s1 != NULL)
|
|
{
|
|
colorcomplement(v->nfa, v->cm, AHEAD, s1, lp, rp);
|
|
newarc(v->nfa, '$', 1, lp, rp);
|
|
newarc(v->nfa, '$', 0, lp, rp);
|
|
return;
|
|
}
|
|
break;
|
|
case LATYPE_BEHIND_POS:
|
|
/* If lookbehind RE is just colorset C, convert to BEHIND(C) */
|
|
if (s1 != NULL)
|
|
{
|
|
cloneouts(v->nfa, s1, lp, rp, BEHIND);
|
|
return;
|
|
}
|
|
break;
|
|
case LATYPE_BEHIND_NEG:
|
|
/* If lookbehind RE is just colorset C, convert to BEHIND(^C)|^ */
|
|
if (s1 != NULL)
|
|
{
|
|
colorcomplement(v->nfa, v->cm, BEHIND, s1, lp, rp);
|
|
newarc(v->nfa, '^', 1, lp, rp);
|
|
newarc(v->nfa, '^', 0, lp, rp);
|
|
return;
|
|
}
|
|
break;
|
|
default:
|
|
assert(NOTREACHED);
|
|
}
|
|
|
|
/* General case: we need a LACON subre and arc */
|
|
n = newlacon(v, begin, end, latype);
|
|
newarc(v->nfa, LACON, n, lp, rp);
|
|
}
|
|
|
|
/*
|
|
* subre - allocate a subre
|
|
*/
|
|
static struct subre *
|
|
subre(struct vars * v,
|
|
int op,
|
|
int flags,
|
|
struct state * begin,
|
|
struct state * end)
|
|
{
|
|
struct subre *ret = v->treefree;
|
|
|
|
/*
|
|
* Checking for stack overflow here is sufficient to protect parse() and
|
|
* its recursive subroutines.
|
|
*/
|
|
if (STACK_TOO_DEEP(v->re))
|
|
{
|
|
ERR(REG_ETOOBIG);
|
|
return NULL;
|
|
}
|
|
|
|
if (ret != NULL)
|
|
v->treefree = ret->left;
|
|
else
|
|
{
|
|
ret = (struct subre *) MALLOC(sizeof(struct subre));
|
|
if (ret == NULL)
|
|
{
|
|
ERR(REG_ESPACE);
|
|
return NULL;
|
|
}
|
|
ret->chain = v->treechain;
|
|
v->treechain = ret;
|
|
}
|
|
|
|
assert(strchr("=b|.*(", op) != NULL);
|
|
|
|
ret->op = op;
|
|
ret->flags = flags;
|
|
ret->id = 0; /* will be assigned later */
|
|
ret->subno = 0;
|
|
ret->min = ret->max = 1;
|
|
ret->left = NULL;
|
|
ret->right = NULL;
|
|
ret->begin = begin;
|
|
ret->end = end;
|
|
ZAPCNFA(ret->cnfa);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* freesubre - free a subRE subtree
|
|
*/
|
|
static void
|
|
freesubre(struct vars * v, /* might be NULL */
|
|
struct subre * sr)
|
|
{
|
|
if (sr == NULL)
|
|
return;
|
|
|
|
if (sr->left != NULL)
|
|
freesubre(v, sr->left);
|
|
if (sr->right != NULL)
|
|
freesubre(v, sr->right);
|
|
|
|
freesrnode(v, sr);
|
|
}
|
|
|
|
/*
|
|
* freesrnode - free one node in a subRE subtree
|
|
*/
|
|
static void
|
|
freesrnode(struct vars * v, /* might be NULL */
|
|
struct subre * sr)
|
|
{
|
|
if (sr == NULL)
|
|
return;
|
|
|
|
if (!NULLCNFA(sr->cnfa))
|
|
freecnfa(&sr->cnfa);
|
|
sr->flags = 0;
|
|
|
|
if (v != NULL && v->treechain != NULL)
|
|
{
|
|
/* we're still parsing, maybe we can reuse the subre */
|
|
sr->left = v->treefree;
|
|
v->treefree = sr;
|
|
}
|
|
else
|
|
FREE(sr);
|
|
}
|
|
|
|
/*
|
|
* optst - optimize a subRE subtree
|
|
*/
|
|
static void
|
|
optst(struct vars * v,
|
|
struct subre * t)
|
|
{
|
|
/*
|
|
* DGP (2007-11-13): I assume it was the programmer's intent to eventually
|
|
* come back and add code to optimize subRE trees, but the routine coded
|
|
* just spends effort traversing the tree and doing nothing. We can do
|
|
* nothing with less effort.
|
|
*/
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* numst - number tree nodes (assigning "id" indexes)
|
|
*/
|
|
static int /* next number */
|
|
numst(struct subre * t,
|
|
int start) /* starting point for subtree numbers */
|
|
{
|
|
int i;
|
|
|
|
assert(t != NULL);
|
|
|
|
i = start;
|
|
t->id = (short) i++;
|
|
if (t->left != NULL)
|
|
i = numst(t->left, i);
|
|
if (t->right != NULL)
|
|
i = numst(t->right, i);
|
|
return i;
|
|
}
|
|
|
|
/*
|
|
* markst - mark tree nodes as INUSE
|
|
*
|
|
* Note: this is a great deal more subtle than it looks. During initial
|
|
* parsing of a regex, all subres are linked into the treechain list;
|
|
* discarded ones are also linked into the treefree list for possible reuse.
|
|
* After we are done creating all subres required for a regex, we run markst()
|
|
* then cleanst(), which results in discarding all subres not reachable from
|
|
* v->tree. We then clear v->treechain, indicating that subres must be found
|
|
* by descending from v->tree. This changes the behavior of freesubre(): it
|
|
* will henceforth FREE() unwanted subres rather than sticking them into the
|
|
* treefree list. (Doing that any earlier would result in dangling links in
|
|
* the treechain list.) This all means that freev() will clean up correctly
|
|
* if invoked before or after markst()+cleanst(); but it would not work if
|
|
* called partway through this state conversion, so we mustn't error out
|
|
* in or between these two functions.
|
|
*/
|
|
static void
|
|
markst(struct subre * t)
|
|
{
|
|
assert(t != NULL);
|
|
|
|
t->flags |= INUSE;
|
|
if (t->left != NULL)
|
|
markst(t->left);
|
|
if (t->right != NULL)
|
|
markst(t->right);
|
|
}
|
|
|
|
/*
|
|
* cleanst - free any tree nodes not marked INUSE
|
|
*/
|
|
static void
|
|
cleanst(struct vars * v)
|
|
{
|
|
struct subre *t;
|
|
struct subre *next;
|
|
|
|
for (t = v->treechain; t != NULL; t = next)
|
|
{
|
|
next = t->chain;
|
|
if (!(t->flags & INUSE))
|
|
FREE(t);
|
|
}
|
|
v->treechain = NULL;
|
|
v->treefree = NULL; /* just on general principles */
|
|
}
|
|
|
|
/*
|
|
* nfatree - turn a subRE subtree into a tree of compacted NFAs
|
|
*/
|
|
static long /* optimize results from top node */
|
|
nfatree(struct vars * v,
|
|
struct subre * t,
|
|
FILE *f) /* for debug output */
|
|
{
|
|
assert(t != NULL && t->begin != NULL);
|
|
|
|
if (t->left != NULL)
|
|
(DISCARD) nfatree(v, t->left, f);
|
|
if (t->right != NULL)
|
|
(DISCARD) nfatree(v, t->right, f);
|
|
|
|
return nfanode(v, t, 0, f);
|
|
}
|
|
|
|
/*
|
|
* nfanode - do one NFA for nfatree or lacons
|
|
*
|
|
* If converttosearch is true, apply makesearch() to the NFA.
|
|
*/
|
|
static long /* optimize results */
|
|
nfanode(struct vars * v,
|
|
struct subre * t,
|
|
int converttosearch,
|
|
FILE *f) /* for debug output */
|
|
{
|
|
struct nfa *nfa;
|
|
long ret = 0;
|
|
|
|
assert(t->begin != NULL);
|
|
|
|
#ifdef REG_DEBUG
|
|
if (f != NULL)
|
|
{
|
|
char idbuf[50];
|
|
|
|
fprintf(f, "\n\n\n========= TREE NODE %s ==========\n",
|
|
stid(t, idbuf, sizeof(idbuf)));
|
|
}
|
|
#endif
|
|
nfa = newnfa(v, v->cm, v->nfa);
|
|
NOERRZ();
|
|
dupnfa(nfa, t->begin, t->end, nfa->init, nfa->final);
|
|
if (!ISERR())
|
|
specialcolors(nfa);
|
|
if (!ISERR())
|
|
ret = optimize(nfa, f);
|
|
if (converttosearch && !ISERR())
|
|
makesearch(v, nfa);
|
|
if (!ISERR())
|
|
compact(nfa, &t->cnfa);
|
|
|
|
freenfa(nfa);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* newlacon - allocate a lookaround-constraint subRE
|
|
*/
|
|
static int /* lacon number */
|
|
newlacon(struct vars * v,
|
|
struct state * begin,
|
|
struct state * end,
|
|
int latype)
|
|
{
|
|
int n;
|
|
struct subre *newlacons;
|
|
struct subre *sub;
|
|
|
|
if (v->nlacons == 0)
|
|
{
|
|
n = 1; /* skip 0th */
|
|
newlacons = (struct subre *) MALLOC(2 * sizeof(struct subre));
|
|
}
|
|
else
|
|
{
|
|
n = v->nlacons;
|
|
newlacons = (struct subre *) REALLOC(v->lacons,
|
|
(n + 1) * sizeof(struct subre));
|
|
}
|
|
if (newlacons == NULL)
|
|
{
|
|
ERR(REG_ESPACE);
|
|
return 0;
|
|
}
|
|
v->lacons = newlacons;
|
|
v->nlacons = n + 1;
|
|
sub = &v->lacons[n];
|
|
sub->begin = begin;
|
|
sub->end = end;
|
|
sub->subno = latype;
|
|
ZAPCNFA(sub->cnfa);
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* freelacons - free lookaround-constraint subRE vector
|
|
*/
|
|
static void
|
|
freelacons(struct subre * subs,
|
|
int n)
|
|
{
|
|
struct subre *sub;
|
|
int i;
|
|
|
|
assert(n > 0);
|
|
for (sub = subs + 1, i = n - 1; i > 0; sub++, i--) /* no 0th */
|
|
if (!NULLCNFA(sub->cnfa))
|
|
freecnfa(&sub->cnfa);
|
|
FREE(subs);
|
|
}
|
|
|
|
/*
|
|
* rfree - free a whole RE (insides of regfree)
|
|
*/
|
|
static void
|
|
rfree(regex_t *re)
|
|
{
|
|
struct guts *g;
|
|
|
|
if (re == NULL || re->re_magic != REMAGIC)
|
|
return;
|
|
|
|
re->re_magic = 0; /* invalidate RE */
|
|
g = (struct guts *) re->re_guts;
|
|
re->re_guts = NULL;
|
|
re->re_fns = NULL;
|
|
if (g != NULL)
|
|
{
|
|
g->magic = 0;
|
|
freecm(&g->cmap);
|
|
if (g->tree != NULL)
|
|
freesubre((struct vars *) NULL, g->tree);
|
|
if (g->lacons != NULL)
|
|
freelacons(g->lacons, g->nlacons);
|
|
if (!NULLCNFA(g->search))
|
|
freecnfa(&g->search);
|
|
FREE(g);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* rcancelrequested - check for external request to cancel regex operation
|
|
*
|
|
* Return nonzero to fail the operation with error code REG_CANCEL,
|
|
* zero to keep going
|
|
*
|
|
* The current implementation is Postgres-specific. If we ever get around
|
|
* to splitting the regex code out as a standalone library, there will need
|
|
* to be some API to let applications define a callback function for this.
|
|
*/
|
|
static int
|
|
rcancelrequested(void)
|
|
{
|
|
return InterruptPending && (QueryCancelPending || ProcDiePending);
|
|
}
|
|
|
|
/*
|
|
* rstacktoodeep - check for stack getting dangerously deep
|
|
*
|
|
* Return nonzero to fail the operation with error code REG_ETOOBIG,
|
|
* zero to keep going
|
|
*
|
|
* The current implementation is Postgres-specific. If we ever get around
|
|
* to splitting the regex code out as a standalone library, there will need
|
|
* to be some API to let applications define a callback function for this.
|
|
*/
|
|
static int
|
|
rstacktoodeep(void)
|
|
{
|
|
return stack_is_too_deep();
|
|
}
|
|
|
|
#ifdef REG_DEBUG
|
|
|
|
/*
|
|
* dump - dump an RE in human-readable form
|
|
*/
|
|
static void
|
|
dump(regex_t *re,
|
|
FILE *f)
|
|
{
|
|
struct guts *g;
|
|
int i;
|
|
|
|
if (re->re_magic != REMAGIC)
|
|
fprintf(f, "bad magic number (0x%x not 0x%x)\n", re->re_magic,
|
|
REMAGIC);
|
|
if (re->re_guts == NULL)
|
|
{
|
|
fprintf(f, "NULL guts!!!\n");
|
|
return;
|
|
}
|
|
g = (struct guts *) re->re_guts;
|
|
if (g->magic != GUTSMAGIC)
|
|
fprintf(f, "bad guts magic number (0x%x not 0x%x)\n", g->magic,
|
|
GUTSMAGIC);
|
|
|
|
fprintf(f, "\n\n\n========= DUMP ==========\n");
|
|
fprintf(f, "nsub %d, info 0%lo, csize %d, ntree %d\n",
|
|
(int) re->re_nsub, re->re_info, re->re_csize, g->ntree);
|
|
|
|
dumpcolors(&g->cmap, f);
|
|
if (!NULLCNFA(g->search))
|
|
{
|
|
fprintf(f, "\nsearch:\n");
|
|
dumpcnfa(&g->search, f);
|
|
}
|
|
for (i = 1; i < g->nlacons; i++)
|
|
{
|
|
struct subre *lasub = &g->lacons[i];
|
|
const char *latype;
|
|
|
|
switch (lasub->subno)
|
|
{
|
|
case LATYPE_AHEAD_POS:
|
|
latype = "positive lookahead";
|
|
break;
|
|
case LATYPE_AHEAD_NEG:
|
|
latype = "negative lookahead";
|
|
break;
|
|
case LATYPE_BEHIND_POS:
|
|
latype = "positive lookbehind";
|
|
break;
|
|
case LATYPE_BEHIND_NEG:
|
|
latype = "negative lookbehind";
|
|
break;
|
|
default:
|
|
latype = "???";
|
|
break;
|
|
}
|
|
fprintf(f, "\nla%d (%s):\n", i, latype);
|
|
dumpcnfa(&lasub->cnfa, f);
|
|
}
|
|
fprintf(f, "\n");
|
|
dumpst(g->tree, f, 0);
|
|
}
|
|
|
|
/*
|
|
* dumpst - dump a subRE tree
|
|
*/
|
|
static void
|
|
dumpst(struct subre * t,
|
|
FILE *f,
|
|
int nfapresent) /* is the original NFA still around? */
|
|
{
|
|
if (t == NULL)
|
|
fprintf(f, "null tree\n");
|
|
else
|
|
stdump(t, f, nfapresent);
|
|
fflush(f);
|
|
}
|
|
|
|
/*
|
|
* stdump - recursive guts of dumpst
|
|
*/
|
|
static void
|
|
stdump(struct subre * t,
|
|
FILE *f,
|
|
int nfapresent) /* is the original NFA still around? */
|
|
{
|
|
char idbuf[50];
|
|
|
|
fprintf(f, "%s. `%c'", stid(t, idbuf, sizeof(idbuf)), t->op);
|
|
if (t->flags & LONGER)
|
|
fprintf(f, " longest");
|
|
if (t->flags & SHORTER)
|
|
fprintf(f, " shortest");
|
|
if (t->flags & MIXED)
|
|
fprintf(f, " hasmixed");
|
|
if (t->flags & CAP)
|
|
fprintf(f, " hascapture");
|
|
if (t->flags & BACKR)
|
|
fprintf(f, " hasbackref");
|
|
if (!(t->flags & INUSE))
|
|
fprintf(f, " UNUSED");
|
|
if (t->subno != 0)
|
|
fprintf(f, " (#%d)", t->subno);
|
|
if (t->min != 1 || t->max != 1)
|
|
{
|
|
fprintf(f, " {%d,", t->min);
|
|
if (t->max != DUPINF)
|
|
fprintf(f, "%d", t->max);
|
|
fprintf(f, "}");
|
|
}
|
|
if (nfapresent)
|
|
fprintf(f, " %ld-%ld", (long) t->begin->no, (long) t->end->no);
|
|
if (t->left != NULL)
|
|
fprintf(f, " L:%s", stid(t->left, idbuf, sizeof(idbuf)));
|
|
if (t->right != NULL)
|
|
fprintf(f, " R:%s", stid(t->right, idbuf, sizeof(idbuf)));
|
|
if (!NULLCNFA(t->cnfa))
|
|
{
|
|
fprintf(f, "\n");
|
|
dumpcnfa(&t->cnfa, f);
|
|
}
|
|
fprintf(f, "\n");
|
|
if (t->left != NULL)
|
|
stdump(t->left, f, nfapresent);
|
|
if (t->right != NULL)
|
|
stdump(t->right, f, nfapresent);
|
|
}
|
|
|
|
/*
|
|
* stid - identify a subtree node for dumping
|
|
*/
|
|
static const char * /* points to buf or constant string */
|
|
stid(struct subre * t,
|
|
char *buf,
|
|
size_t bufsize)
|
|
{
|
|
/* big enough for hex int or decimal t->id? */
|
|
if (bufsize < sizeof(void *) * 2 + 3 || bufsize < sizeof(t->id) * 3 + 1)
|
|
return "unable";
|
|
if (t->id != 0)
|
|
sprintf(buf, "%d", t->id);
|
|
else
|
|
sprintf(buf, "%p", t);
|
|
return buf;
|
|
}
|
|
#endif /* REG_DEBUG */
|
|
|
|
|
|
#include "regc_lex.c"
|
|
#include "regc_color.c"
|
|
#include "regc_nfa.c"
|
|
#include "regc_cvec.c"
|
|
#include "regc_pg_locale.c"
|
|
#include "regc_locale.c"
|