/*
* re_*comp and friends - compile REs
* This file #includes several others (see the bottom).
*
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
*
* Development of this software was funded, in part, by Cray Research Inc.,
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
* Corporation, none of whom are responsible for the results. The author
* thanks all of them.
*
* Redistribution and use in source and binary forms -- with or without
* modification -- are permitted for any purpose, provided that
* redistributions in source form retain this entire copyright notice and
* indicate the origin and nature of any modifications.
*
* I'd appreciate being given credit for this package in the documentation
* of software which uses it, but that is not a requirement.
*
* THIS SOFTWARE IS PROVIDED ``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
* HENRY SPENCER 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.
*
*/
#include "regguts.h"
/*
* forward declarations, up here so forward datatypes etc. are defined early
*/
/* =====^!^===== begin forwards =====^!^===== */
/* automatically gathered by fwd; do not hand-edit */
/* === regcomp.c === */
int compile _ANSI_ARGS_((regex_t *, CONST chr *, size_t, int));
static VOID moresubs _ANSI_ARGS_((struct vars *, int));
static int freev _ANSI_ARGS_((struct vars *, int));
static VOID makesearch _ANSI_ARGS_((struct vars *, struct nfa *));
static struct subre *parse _ANSI_ARGS_((struct vars *, int, int, struct state *, struct state *));
static struct subre *parsebranch _ANSI_ARGS_((struct vars *, int, int, struct state *, struct state *, int));
static VOID parseqatom _ANSI_ARGS_((struct vars *, int, int, struct state *, struct state *, struct subre *));
static VOID nonword _ANSI_ARGS_((struct vars *, int, struct state *, struct state *));
static VOID word _ANSI_ARGS_((struct vars *, int, struct state *, struct state *));
static int scannum _ANSI_ARGS_((struct vars *));
static VOID repeat _ANSI_ARGS_((struct vars *, struct state *, struct state *, int, int));
static VOID bracket _ANSI_ARGS_((struct vars *, struct state *, struct state *));
static VOID cbracket _ANSI_ARGS_((struct vars *, struct state *, struct state *));
static VOID brackpart _ANSI_ARGS_((struct vars *, struct state *, struct state *));
static chr *scanplain _ANSI_ARGS_((struct vars *));
static VOID leaders _ANSI_ARGS_((struct vars *, struct cvec *));
static VOID onechr _ANSI_ARGS_((struct vars *, pchr, struct state *, struct state *));
static VOID dovec _ANSI_ARGS_((struct vars *, struct cvec *, struct state *, struct state *));
static celt nextleader _ANSI_ARGS_((struct vars *, pchr, pchr));
static VOID wordchrs _ANSI_ARGS_((struct vars *));
static struct subre *subre _ANSI_ARGS_((struct vars *, int, int, struct state *, struct state *));
static VOID freesubre _ANSI_ARGS_((struct vars *, struct subre *));
static VOID freesrnode _ANSI_ARGS_((struct vars *, struct subre *));
static VOID optst _ANSI_ARGS_((struct vars *, struct subre *));
static int numst _ANSI_ARGS_((struct subre *, int));
static VOID markst _ANSI_ARGS_((struct subre *));
static VOID cleanst _ANSI_ARGS_((struct vars *));
static long nfatree _ANSI_ARGS_((struct vars *, struct subre *, FILE *));
static long nfanode _ANSI_ARGS_((struct vars *, struct subre *, FILE *));
static int newlacon _ANSI_ARGS_((struct vars *, struct state *, struct state *, int));
static VOID freelacons _ANSI_ARGS_((struct subre *, int));
static VOID rfree _ANSI_ARGS_((regex_t *));
static VOID dump _ANSI_ARGS_((regex_t *, FILE *));
static VOID dumpst _ANSI_ARGS_((struct subre *, FILE *, int));
static VOID stdump _ANSI_ARGS_((struct subre *, FILE *, int));
static char *stid _ANSI_ARGS_((struct subre *, char *, size_t));
/* === regc_lex.c === */
static VOID lexstart _ANSI_ARGS_((struct vars *));
static VOID prefixes _ANSI_ARGS_((struct vars *));
static VOID lexnest _ANSI_ARGS_((struct vars *, chr *, chr *));
static VOID lexword _ANSI_ARGS_((struct vars *));
static int next _ANSI_ARGS_((struct vars *));
static int lexescape _ANSI_ARGS_((struct vars *));
static chr lexdigits _ANSI_ARGS_((struct vars *, int, int, int));
static int brenext _ANSI_ARGS_((struct vars *, pchr));
static VOID skip _ANSI_ARGS_((struct vars *));
static chr newline _ANSI_ARGS_((NOPARMS));
#ifdef REG_DEBUG
static chr *ch _ANSI_ARGS_((NOPARMS));
#endif
static chr chrnamed _ANSI_ARGS_((struct vars *, chr *, chr *, pchr));
/* === regc_color.c === */
static VOID initcm _ANSI_ARGS_((struct vars *, struct colormap *));
static VOID freecm _ANSI_ARGS_((struct colormap *));
static VOID cmtreefree _ANSI_ARGS_((struct colormap *, union tree *, int));
static color setcolor _ANSI_ARGS_((struct colormap *, pchr, pcolor));
static color maxcolor _ANSI_ARGS_((struct colormap *));
static color newcolor _ANSI_ARGS_((struct colormap *));
static VOID freecolor _ANSI_ARGS_((struct colormap *, pcolor));
static color pseudocolor _ANSI_ARGS_((struct colormap *));
static color subcolor _ANSI_ARGS_((struct colormap *, pchr c));
static color newsub _ANSI_ARGS_((struct colormap *, pcolor));
static VOID subrange _ANSI_ARGS_((struct vars *, pchr, pchr, struct state *, struct state *));
static VOID subblock _ANSI_ARGS_((struct vars *, pchr, struct state *, struct state *));
static VOID okcolors _ANSI_ARGS_((struct nfa *, struct colormap *));
static VOID colorchain _ANSI_ARGS_((struct colormap *, struct arc *));
static VOID uncolorchain _ANSI_ARGS_((struct colormap *, struct arc *));
static int singleton _ANSI_ARGS_((struct colormap *, pchr c));
static VOID rainbow _ANSI_ARGS_((struct nfa *, struct colormap *, int, pcolor, struct state *, struct state *));
static VOID colorcomplement _ANSI_ARGS_((struct nfa *, struct colormap *, int, struct state *, struct state *, struct state *));
#ifdef REG_DEBUG
static VOID dumpcolors _ANSI_ARGS_((struct colormap *, FILE *));
static VOID fillcheck _ANSI_ARGS_((struct colormap *, union tree *, int, FILE *));
static VOID dumpchr _ANSI_ARGS_((pchr, FILE *));
#endif
/* === regc_nfa.c === */
static struct nfa *newnfa _ANSI_ARGS_((struct vars *, struct colormap *, struct nfa *));
static VOID freenfa _ANSI_ARGS_((struct nfa *));
static struct state *newstate _ANSI_ARGS_((struct nfa *));
static struct state *newfstate _ANSI_ARGS_((struct nfa *, int flag));
static VOID dropstate _ANSI_ARGS_((struct nfa *, struct state *));
static VOID freestate _ANSI_ARGS_((struct nfa *, struct state *));
static VOID destroystate _ANSI_ARGS_((struct nfa *, struct state *));
static VOID newarc _ANSI_ARGS_((struct nfa *, int, pcolor, struct state *, struct state *));
static struct arc *allocarc _ANSI_ARGS_((struct nfa *, struct state *));
static VOID freearc _ANSI_ARGS_((struct nfa *, struct arc *));
static struct arc *findarc _ANSI_ARGS_((struct state *, int, pcolor));
static VOID cparc _ANSI_ARGS_((struct nfa *, struct arc *, struct state *, struct state *));
static VOID moveins _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID copyins _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID moveouts _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID copyouts _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID cloneouts _ANSI_ARGS_((struct nfa *, struct state *, struct state *, struct state *, int));
static VOID delsub _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID deltraverse _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID dupnfa _ANSI_ARGS_((struct nfa *, struct state *, struct state *, struct state *, struct state *));
static VOID duptraverse _ANSI_ARGS_((struct nfa *, struct state *, struct state *));
static VOID cleartraverse _ANSI_ARGS_((struct nfa *, struct state *));
static VOID specialcolors _ANSI_ARGS_((struct nfa *));
static long optimize _ANSI_ARGS_((struct nfa *, FILE *));
static VOID pullback _ANSI_ARGS_((struct nfa *, FILE *));
static int pull _ANSI_ARGS_((struct nfa *, struct arc *));
static VOID pushfwd _ANSI_ARGS_((struct nfa *, FILE *));
static int push _ANSI_ARGS_((struct nfa *, struct arc *));
#define INCOMPATIBLE 1 /* destroys arc */
#define SATISFIED 2 /* constraint satisfied */
#define COMPATIBLE 3 /* compatible but not satisfied yet */
static int combine _ANSI_ARGS_((struct arc *, struct arc *));
static VOID fixempties _ANSI_ARGS_((struct nfa *, FILE *));
static int unempty _ANSI_ARGS_((struct nfa *, struct arc *));
static VOID cleanup _ANSI_ARGS_((struct nfa *));
static VOID markreachable _ANSI_ARGS_((struct nfa *, struct state *, struct state *, struct state *));
static VOID markcanreach _ANSI_ARGS_((struct nfa *, struct state *, struct state *, struct state *));
static long analyze _ANSI_ARGS_((struct nfa *));
static VOID compact _ANSI_ARGS_((struct nfa *, struct cnfa *));
static VOID carcsort _ANSI_ARGS_((struct carc *, struct carc *));
static VOID freecnfa _ANSI_ARGS_((struct cnfa *));
static VOID dumpnfa _ANSI_ARGS_((struct nfa *, FILE *));
#ifdef REG_DEBUG
static VOID dumpstate _ANSI_ARGS_((struct state *, FILE *));
static VOID dumparcs _ANSI_ARGS_((struct state *, FILE *));
static int dumprarcs _ANSI_ARGS_((struct arc *, struct state *, FILE *, int));
static VOID dumparc _ANSI_ARGS_((struct arc *, struct state *, FILE *));
#endif
static VOID dumpcnfa _ANSI_ARGS_((struct cnfa *, FILE *));
#ifdef REG_DEBUG
static VOID dumpcstate _ANSI_ARGS_((int, struct carc *, struct cnfa *, FILE *));
#endif
/* === regc_cvec.c === */
static struct cvec *newcvec _ANSI_ARGS_((int, int, int));
static struct cvec *clearcvec _ANSI_ARGS_((struct cvec *));
static VOID addchr _ANSI_ARGS_((struct cvec *, pchr));
static VOID addrange _ANSI_ARGS_((struct cvec *, pchr, pchr));
static VOID addmcce _ANSI_ARGS_((struct cvec *, chr *, chr *));
static int haschr _ANSI_ARGS_((struct cvec *, pchr));
static struct cvec *getcvec _ANSI_ARGS_((struct vars *, int, int, int));
static VOID freecvec _ANSI_ARGS_((struct cvec *));
/* === regc_locale.c === */
static int nmcces _ANSI_ARGS_((struct vars *));
static int nleaders _ANSI_ARGS_((struct vars *));
static struct cvec *allmcces _ANSI_ARGS_((struct vars *, struct cvec *));
static celt element _ANSI_ARGS_((struct vars *, chr *, chr *));
static struct cvec *range _ANSI_ARGS_((struct vars *, celt, celt, int));
static int before _ANSI_ARGS_((celt, celt));
static struct cvec *eclass _ANSI_ARGS_((struct vars *, celt, int));
static struct cvec *cclass _ANSI_ARGS_((struct vars *, chr *, chr *, int));
static struct cvec *allcases _ANSI_ARGS_((struct vars *, pchr));
static int cmp _ANSI_ARGS_((CONST chr *, CONST chr *, size_t));
static int casecmp _ANSI_ARGS_((CONST chr *, CONST chr *, size_t));
/* automatically gathered by fwd; do not hand-edit */
/* =====^!^===== end forwards =====^!^===== */
/* internal variables, bundled for easy passing around */
struct vars {
regex_t *re;
chr *now; /* scan pointer into string */
chr *stop; /* end of string */
chr *savenow; /* saved now and stop for "subroutine call" */
chr *savestop;
int err; /* error code (0 if none) */
int cflags; /* copy of compile flags */
int lasttype; /* type of previous token */
int nexttype; /* type of next token */
chr nextvalue; /* value (if any) of next token */
int lexcon; /* lexical context type (see lex.c) */
int nsubexp; /* subexpression count */
struct subre **subs; /* subRE pointer vector */
size_t nsubs; /* length of vector */
struct subre *sub10[10]; /* initial vector, enough for most */
struct nfa *nfa; /* the NFA */
struct colormap *cm; /* character color map */
color nlcolor; /* color of newline */
struct state *wordchrs; /* state in nfa holding word-char outarcs */
struct subre *tree; /* subexpression tree */
struct subre *treechain; /* all tree nodes allocated */
struct subre *treefree; /* any free tree nodes */
int ntree; /* number of tree nodes */
struct cvec *cv; /* interface cvec */
struct cvec *cv2; /* utility cvec */
struct cvec *mcces; /* collating-element information */
# define ISCELEADER(v,c) (v->mcces != NULL && haschr(v->mcces, (c)))
struct state *mccepbegin; /* in nfa, start of MCCE prototypes */
struct state *mccepend; /* in nfa, end of MCCE prototypes */
struct subre *lacons; /* lookahead-constraint vector */
int nlacons; /* size of lacons */
};
/* parsing macros; most know that `v' is the struct vars pointer */
#define NEXT() (next(v)) /* advance by one token */
#define SEE(t) (v->nexttype == (t)) /* is next token this? */
#define EAT(t) (SEE(t) && next(v)) /* if next is this, swallow it */
#define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
#define ISERR() VISERR(v)
#define VERR(vv,e) ((vv)->nexttype = EOS, ((vv)->err) ? (vv)->err :\
((vv)->err = (e)))
#define ERR(e) VERR(v, e) /* record an error */
#define NOERR() {if (ISERR()) return;} /* if error seen, return */
#define NOERRN() {if (ISERR()) return NULL;} /* NOERR with retval */
#define NOERRZ() {if (ISERR()) return 0;} /* NOERR with retval */
#define INSIST(c, e) ((c) ? 0 : ERR(e)) /* if condition false, error */
#define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */
#define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y)
/* token type codes, some also used as NFA arc types */
#define EMPTY 'n' /* no token present */
#define EOS 'e' /* end of string */
#define PLAIN 'p' /* ordinary character */
#define DIGIT 'd' /* digit (in bound) */
#define BACKREF 'b' /* back reference */
#define COLLEL 'I' /* start of [. */
#define ECLASS 'E' /* start of [= */
#define CCLASS 'C' /* start of [: */
#define END 'X' /* end of [. [= [: */
#define RANGE 'R' /* - within [] which might be range delim. */
#define LACON 'L' /* lookahead constraint subRE */
#define AHEAD 'a' /* color-lookahead arc */
#define BEHIND 'r' /* color-lookbehind arc */
#define WBDRY 'w' /* word boundary constraint */
#define NWBDRY 'W' /* non-word-boundary constraint */
#define SBEGIN 'A' /* beginning of string (even if not BOL) */
#define SEND 'Z' /* end of string (even if not EOL) */
#define PREFER 'P' /* length preference */
/* is an arc colored, and hence on a color chain? */
#define COLORED(a) ((a)->type == PLAIN || (a)->type == AHEAD || \
(a)->type == BEHIND)
/* static function list */
static struct fns functions = {
rfree, /* regfree insides */
};
/*
- compile - compile regular expression
^ int compile(regex_t *, CONST chr *, size_t, int);
*/
int
compile(re, string, len, flags)
regex_t *re;
CONST chr *string;
size_t len;
int flags;
{
struct vars var;
struct vars *v = &var;
struct guts *g;
int i;
size_t j;
FILE *debug = (flags®_PROGRESS) ? stdout : (FILE *)NULL;
# define CNOERR() { if (ISERR()) return freev(v, v->err); }
/* sanity checks */
if (re == NULL || string == NULL)
return REG_INVARG;
if ((flags®_QUOTE) &&
(flags&(REG_ADVANCED|REG_EXPANDED|REG_NEWLINE)))
return REG_INVARG;
if (!(flags®_EXTENDED) && (flags®_ADVF))
return REG_INVARG;
/* initial setup (after which freev() is callable) */
v->re = re;
v->now = (chr *)string;
v->stop = v->now + len;
v->savenow = v->savestop = NULL;
v->err = 0;
v->cflags = flags;
v->nsubexp = 0;
v->subs = v->sub10;
v->nsubs = 10;
for (j = 0; j < v->nsubs; j++)
v->subs[j] = NULL;
v->nfa = NULL;
v->cm = NULL;
v->nlcolor = COLORLESS;
v->wordchrs = NULL;
v->tree = NULL;
v->treechain = NULL;
v->treefree = NULL;
v->cv = NULL;
v->cv2 = NULL;
v->mcces = NULL;
v->lacons = NULL;
v->nlacons = 0;
re->re_magic = REMAGIC;
re->re_info = 0; /* bits get set during parse */
re->re_csize = sizeof(chr);
re->re_guts = NULL;
re->re_fns = VS(&functions);
/* more complex setup, malloced things */
re->re_guts = VS(MALLOC(sizeof(struct guts)));
if (re->re_guts == NULL)
return freev(v, REG_ESPACE);
g = (struct guts *)re->re_guts;
g->tree = NULL;
initcm(v, &g->cmap);
v->cm = &g->cmap;
g->lacons = NULL;
g->nlacons = 0;
ZAPCNFA(g->search);
v->nfa = newnfa(v, v->cm, (struct nfa *)NULL);
CNOERR();
v->cv = newcvec(100, 20, 10);
if (v->cv == NULL)
return freev(v, REG_ESPACE);
i = nmcces(v);
if (i > 0) {
v->mcces = newcvec(nleaders(v), 0, i);
CNOERR();
v->mcces = allmcces(v, v->mcces);
leaders(v, v->mcces);
addmcce(v->mcces, (chr *)NULL, (chr *)NULL); /* dummy */
}
CNOERR();
/* parsing */
lexstart(v); /* also handles prefixes */
if ((v->cflags®_NLSTOP) || (v->cflags®_NLANCH)) {
/* assign newline a unique color */
v->nlcolor = subcolor(v->cm, newline());
okcolors(v->nfa, v->cm);
}
CNOERR();
v->tree = parse(v, EOS, PLAIN, v->nfa->init, v->nfa->final);
assert(SEE(EOS)); /* even if error; ISERR() => SEE(EOS) */
CNOERR();
assert(v->tree != NULL);
/* finish setup of nfa and its subre tree */
specialcolors(v->nfa);
CNOERR();
if (debug != NULL) {
fprintf(debug, "\n\n\n========= RAW ==========\n");
dumpnfa(v->nfa, debug);
dumpst(v->tree, debug, 1);
}
optst(v, v->tree);
v->ntree = numst(v->tree, 1);
markst(v->tree);
cleanst(v);
if (debug != NULL) {
fprintf(debug, "\n\n\n========= TREE FIXED ==========\n");
dumpst(v->tree, debug, 1);
}
/* 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++) {
if (debug != NULL)
fprintf(debug, "\n\n\n========= LA%d ==========\n", i);
nfanode(v, &v->lacons[i], debug);
}
CNOERR();
if (v->tree->flags&SHORTER)
NOTE(REG_USHORTEST);
/* build compacted NFAs for tree, lacons, fast search */
if (debug != NULL)
fprintf(debug, "\n\n\n========= SEARCH ==========\n");
/* 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®_ICASE) ? casecmp : cmp;
g->lacons = v->lacons;
v->lacons = NULL;
g->nlacons = v->nlacons;
if (flags®_DUMP)
dump(re, stdout);
assert(v->err == 0);
return freev(v, 0);
}
/*
- moresubs - enlarge subRE vector
^ static VOID moresubs(struct vars *, int);
*/
static VOID
moresubs(v, wanted)
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 *, int);
*/
static int
freev(v, err)
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->mcces != NULL)
freecvec(v->mcces);
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 *, struct nfa *);
*/
static VOID
makesearch(v, nfa)
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 */
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;
if (b != NULL) { /* must be split */
if (s->tmp == NULL) { /* if not already in the list */
/* (fixes bugs 505048, 230589, */
/* 840258, 504785) */
s->tmp = slist;
slist = s;
}
}
}
/* do the splits */
for (s = slist; s != NULL; s = s2) {
s2 = newstate(nfa);
copyouts(nfa, s, s2);
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->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 *, int, int, struct state *,
^ struct state *);
*/
static struct subre *
parse(v, stopper, type, init, final)
struct vars *v;
int stopper; /* EOS or ')' */
int type; /* LACON (lookahead 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 *, int, int, struct state *,
^ struct state *, int);
*/
static struct subre *
parsebranch(v, stopper, type, left, right, partial)
struct vars *v;
int stopper; /* EOS or ')' */
int type; /* LACON (lookahead 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);
}
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 *, int, int, struct state *,
^ struct state *, struct subre *);
*/
static VOID
parseqatom(v, stopper, type, lp, rp, top)
struct vars *v;
int stopper; /* EOS or ')' */
int type; /* LACON (lookahead 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 pos; /* positive lookahead? */
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®_NLANCH)
ARCV(BEHIND, v->nlcolor);
NEXT();
return;
break;
case '$':
ARCV('$', 1);
if (v->cflags®_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: /* lookahead constraint */
pos = v->nextvalue;
NEXT();
s = newstate(v->nfa);
s2 = newstate(v->nfa);
NOERR();
t = parse(v, ')', LACON, s, s2);
freesubre(v, t); /* internal structure irrelevant */
assert(SEE(')') || ISERR());
NEXT();
n = newlacon(v, s, s2, pos);
NOERR();
ARCV(LACON, n);
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®_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®_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, ')', PLAIN, 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);
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 = INFINITY;
qprefer = (v->nextvalue) ? LONGER : SHORTER;
NEXT();
break;
case '+':
m = 1;
n = INFINITY;
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 = INFINITY;
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
*
* ---> [s] ---prefix---> [begin] ---atom---> [end] ----rest---> [rp]
* / /
* [lp] ----> [s2] ----bypass---------------------
*
* where bypass is an empty, and prefix is some repetitions of atom
*/
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); /* and spots for prefix and bypass */
s2 = newstate(v->nfa);
NOERR();
EMPTYARC(lp, s);
EMPTYARC(lp, s2);
NOERR();
/* break remaining subRE into x{...} and what follows */
t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp);
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);
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; first, turn x{0,...} into x{1,...}|empty */
if (m == 0) {
EMPTYARC(s2, atom->end); /* the bypass */
assert(PREF(qprefer) != 0);
f = COMBINE(qprefer, atom->flags);
t = subre(v, '|', f, lp, atom->end);
NOERR();
t->left = atom;
t->right = subre(v, '|', PREF(f), s2, atom->end);
NOERR();
t->right->left = subre(v, '=', 0, s2, atom->end);
NOERR();
*atomp = t;
atomp = &t->left;
m = 1;
}
/* deal with the rest of the quantifier */
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);
} else if (m == 1 && n == 1) {
/* no/vacuous quantifier: done */
EMPTYARC(s, atom->begin); /* empty prefix */
} else {
/* turn x{m,n} into x{m-1,n-1}x, with capturing */
/* parens in only second x */
dupnfa(v->nfa, atom->begin, atom->end, s, atom->begin);
assert(m >= 1 && m != INFINITY && n >= 1);
repeat(v, s, atom->begin, m-1, (n == INFINITY) ? 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;
}
/* and finally, look after that postponed recursion */
t = top->right;
if (!(SEE('|') || SEE(stopper) || SEE(EOS)))
t->right = parsebranch(v, stopper, type, atom->end, rp, 1);
else {
EMPTYARC(atom->end, rp);
t->right = subre(v, '=', 0, atom->end, rp);
}
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 *, int, struct state *, struct state *);
*/
static VOID
nonword(v, dir, lp, rp)
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 *, int, struct state *, struct state *);
*/
static VOID
word(v, dir, lp, rp)
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 scannum(struct vars *);
*/
static int /* value, <= DUPMAX */
scannum(v)
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 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 *, struct state *, struct state *, int, int);
*/
static VOID
repeat(v, lp, rp, m, n)
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) == INFINITY) ? 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 *, struct state *, struct state *);
*/
static VOID
bracket(v, lp, rp)
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 *, struct state *, struct state *);
*/
static VOID
cbracket(v, lp, rp)
struct vars *v;
struct state *lp;
struct state *rp;
{
struct state *left = newstate(v->nfa);
struct state *right = newstate(v->nfa);
struct state *s;
struct arc *a; /* arc from lp */
struct arc *ba; /* arc from left, from bracket() */
struct arc *pa; /* MCCE-prototype arc */
color co;
chr *p;
int i;
NOERR();
bracket(v, left, right);
if (v->cflags®_NLSTOP)
newarc(v->nfa, PLAIN, v->nlcolor, left, right);
NOERR();
assert(lp->nouts == 0); /* all outarcs will be ours */
/* easy part of complementing */
colorcomplement(v->nfa, v->cm, PLAIN, left, lp, rp);
NOERR();
if (v->mcces == NULL) { /* no MCCEs -- we're done */
dropstate(v->nfa, left);
assert(right->nins == 0);
freestate(v->nfa, right);
return;
}
/* but complementing gets messy in the presence of MCCEs... */
NOTE(REG_ULOCALE);
for (p = v->mcces->chrs, i = v->mcces->nchrs; i > 0; p++, i--) {
co = GETCOLOR(v->cm, *p);
a = findarc(lp, PLAIN, co);
ba = findarc(left, PLAIN, co);
if (ba == NULL) {
assert(a != NULL);
freearc(v->nfa, a);
} else {
assert(a == NULL);
}
s = newstate(v->nfa);
NOERR();
newarc(v->nfa, PLAIN, co, lp, s);
NOERR();
pa = findarc(v->mccepbegin, PLAIN, co);
assert(pa != NULL);
if (ba == NULL) { /* easy case, need all of them */
cloneouts(v->nfa, pa->to, s, rp, PLAIN);
newarc(v->nfa, '$', 1, s, rp);
newarc(v->nfa, '$', 0, s, rp);
colorcomplement(v->nfa, v->cm, AHEAD, pa->to, s, rp);
} else { /* must be selective */
if (findarc(ba->to, '$', 1) == NULL) {
newarc(v->nfa, '$', 1, s, rp);
newarc(v->nfa, '$', 0, s, rp);
colorcomplement(v->nfa, v->cm, AHEAD, pa->to,
s, rp);
}
for (pa = pa->to->outs; pa != NULL; pa = pa->outchain)
if (findarc(ba->to, PLAIN, pa->co) == NULL)
newarc(v->nfa, PLAIN, pa->co, s, rp);
if (s->nouts == 0) /* limit of selectivity: none */
dropstate(v->nfa, s); /* frees arc too */
}
NOERR();
}
delsub(v->nfa, left, right);
assert(left->nouts == 0);
freestate(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 *, struct state *, struct state *);
*/
static VOID
brackpart(v, lp, rp)
struct vars *v;
struct state *lp;
struct state *rp;
{
celt startc;
celt endc;
struct cvec *cv;
chr *startp;
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, not MCCE leader) */
if (!SEE(RANGE) && !ISCELEADER(v, c[0])) {
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®_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®_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®_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 chr *scanplain(struct vars *);
*/
static chr * /* just after end of sequence */
scanplain(v)
struct vars *v;
{
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;
}
/*
- leaders - process a cvec of collating elements to also include leaders
* Also gives all characters involved their own colors, which is almost
* certainly necessary, and sets up little disconnected subNFA.
^ static VOID leaders(struct vars *, struct cvec *);
*/
static VOID
leaders(v, cv)
struct vars *v;
struct cvec *cv;
{
int mcce;
chr *p;
chr leader;
struct state *s;
struct arc *a;
v->mccepbegin = newstate(v->nfa);
v->mccepend = newstate(v->nfa);
NOERR();
for (mcce = 0; mcce < cv->nmcces; mcce++) {
p = cv->mcces[mcce];
leader = *p;
if (!haschr(cv, leader)) {
addchr(cv, leader);
s = newstate(v->nfa);
newarc(v->nfa, PLAIN, subcolor(v->cm, leader),
v->mccepbegin, s);
okcolors(v->nfa, v->cm);
} else {
a = findarc(v->mccepbegin, PLAIN,
GETCOLOR(v->cm, leader));
assert(a != NULL);
s = a->to;
assert(s != v->mccepend);
}
p++;
assert(*p != 0 && *(p+1) == 0); /* only 2-char MCCEs for now */
newarc(v->nfa, PLAIN, subcolor(v->cm, *p), s, v->mccepend);
okcolors(v->nfa, v->cm);
}
}
/*
- 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 *, pchr, struct state *, struct state *);
*/
static VOID
onechr(v, c, lp, rp)
struct vars *v;
pchr c;
struct state *lp;
struct state *rp;
{
if (!(v->cflags®_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
* This one has to handle the messy cases, like MCCEs and MCCE leaders.
^ static VOID dovec(struct vars *, struct cvec *, struct state *,
^ struct state *);
*/
static VOID
dovec(v, cv, lp, rp)
struct vars *v;
struct cvec *cv;
struct state *lp;
struct state *rp;
{
chr ch, from, to;
celt ce;
chr *p;
int i;
color co;
struct cvec *leads;
struct arc *a;
struct arc *pa; /* arc in prototype */
struct state *s;
struct state *ps; /* state in prototype */
/* need a place to store leaders, if any */
if (nmcces(v) > 0) {
assert(v->mcces != NULL);
if (v->cv2 == NULL || v->cv2->nchrs < v->mcces->nchrs) {
if (v->cv2 != NULL)
free(v->cv2);
v->cv2 = newcvec(v->mcces->nchrs, 0, v->mcces->nmcces);
NOERR();
leads = v->cv2;
} else
leads = clearcvec(v->cv2);
} else
leads = NULL;
/* first, get the ordinary characters out of the way */
for (p = cv->chrs, i = cv->nchrs; i > 0; p++, i--) {
ch = *p;
if (!ISCELEADER(v, ch))
newarc(v->nfa, PLAIN, subcolor(v->cm, ch), lp, rp);
else {
assert(singleton(v->cm, ch));
assert(leads != NULL);
if (!haschr(leads, ch))
addchr(leads, ch);
}
}
/* and the ranges */
for (p = cv->ranges, i = cv->nranges; i > 0; p += 2, i--) {
from = *p;
to = *(p+1);
while (from <= to && (ce = nextleader(v, from, to)) != NOCELT) {
if (from < ce)
subrange(v, from, ce - 1, lp, rp);
assert(singleton(v->cm, ce));
assert(leads != NULL);
if (!haschr(leads, ce))
addchr(leads, ce);
from = ce + 1;
}
if (from <= to)
subrange(v, from, to, lp, rp);
}
if ((leads == NULL || leads->nchrs == 0) && cv->nmcces == 0)
return;
/* deal with the MCCE leaders */
NOTE(REG_ULOCALE);
for (p = leads->chrs, i = leads->nchrs; i > 0; p++, i--) {
co = GETCOLOR(v->cm, *p);
a = findarc(lp, PLAIN, co);
if (a != NULL)
s = a->to;
else {
s = newstate(v->nfa);
NOERR();
newarc(v->nfa, PLAIN, co, lp, s);
NOERR();
}
pa = findarc(v->mccepbegin, PLAIN, co);
assert(pa != NULL);
ps = pa->to;
newarc(v->nfa, '$', 1, s, rp);
newarc(v->nfa, '$', 0, s, rp);
colorcomplement(v->nfa, v->cm, AHEAD, ps, s, rp);
NOERR();
}
/* and the MCCEs */
for (i = 0; i < cv->nmcces; i++) {
p = cv->mcces[i];
assert(singleton(v->cm, *p));
if (!singleton(v->cm, *p)) {
ERR(REG_ASSERT);
return;
}
ch = *p++;
co = GETCOLOR(v->cm, ch);
a = findarc(lp, PLAIN, co);
if (a != NULL)
s = a->to;
else {
s = newstate(v->nfa);
NOERR();
newarc(v->nfa, PLAIN, co, lp, s);
NOERR();
}
assert(*p != 0); /* at least two chars */
assert(singleton(v->cm, *p));
ch = *p++;
co = GETCOLOR(v->cm, ch);
assert(*p == 0); /* and only two, for now */
newarc(v->nfa, PLAIN, co, s, rp);
NOERR();
}
}
/*
- nextleader - find next MCCE leader within range
^ static celt nextleader(struct vars *, pchr, pchr);
*/
static celt /* NOCELT means none */
nextleader(v, from, to)
struct vars *v;
pchr from;
pchr to;
{
int i;
chr *p;
chr ch;
celt it = NOCELT;
if (v->mcces == NULL)
return it;
for (i = v->mcces->nchrs, p = v->mcces->chrs; i > 0; i--, p++) {
ch = *p;
if (from <= ch && ch <= to)
if (it == NOCELT || ch < it)
it = ch;
}
return it;
}
/*
- 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 *);
*/
static VOID
wordchrs(v)
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;
}
/*
- subre - allocate a subre
^ static struct subre *subre(struct vars *, int, int, struct state *,
^ struct state *);
*/
static struct subre *
subre(v, op, flags, begin, end)
struct vars *v;
int op;
int flags;
struct state *begin;
struct state *end;
{
struct subre *ret;
ret = v->treefree;
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->retry = 0;
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 *, struct subre *);
*/
static VOID
freesubre(v, sr)
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 *, struct subre *);
*/
static VOID
freesrnode(v, sr)
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) {
sr->left = v->treefree;
v->treefree = sr;
} else
FREE(sr);
}
/*
- optst - optimize a subRE subtree
^ static VOID optst(struct vars *, struct subre *);
*/
static VOID
optst(v, t)
struct vars *v;
struct subre *t;
{
if (t == NULL)
return;
/* recurse through children */
if (t->left != NULL)
optst(v, t->left);
if (t->right != NULL)
optst(v, t->right);
}
/*
- numst - number tree nodes (assigning retry indexes)
^ static int numst(struct subre *, int);
*/
static int /* next number */
numst(t, start)
struct subre *t;
int start; /* starting point for subtree numbers */
{
int i;
assert(t != NULL);
i = start;
t->retry = (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
^ static VOID markst(struct subre *);
*/
static VOID
markst(t)
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 *);
*/
static VOID
cleanst(v)
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 nfatree(struct vars *, struct subre *, FILE *);
*/
static long /* optimize results from top node */
nfatree(v, t, f)
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, f);
}
/*
- nfanode - do one NFA for nfatree
^ static long nfanode(struct vars *, struct subre *, FILE *);
*/
static long /* optimize results */
nfanode(v, t, f)
struct vars *v;
struct subre *t;
FILE *f; /* for debug output */
{
struct nfa *nfa;
long ret = 0;
char idbuf[50];
assert(t->begin != NULL);
if (f != NULL)
fprintf(f, "\n\n\n========= TREE NODE %s ==========\n",
stid(t, idbuf, sizeof(idbuf)));
nfa = newnfa(v, v->cm, v->nfa);
NOERRZ();
dupnfa(nfa, t->begin, t->end, nfa->init, nfa->final);
if (!ISERR()) {
specialcolors(nfa);
ret = optimize(nfa, f);
}
if (!ISERR())
compact(nfa, &t->cnfa);
freenfa(nfa);
return ret;
}
/*
- newlacon - allocate a lookahead-constraint subRE
^ static int newlacon(struct vars *, struct state *, struct state *, int);
*/
static int /* lacon number */
newlacon(v, begin, end, pos)
struct vars *v;
struct state *begin;
struct state *end;
int pos;
{
int n;
struct subre *sub;
if (v->nlacons == 0) {
v->lacons = (struct subre *)MALLOC(2 * sizeof(struct subre));
n = 1; /* skip 0th */
v->nlacons = 2;
} else {
v->lacons = (struct subre *)REALLOC(v->lacons,
(v->nlacons+1)*sizeof(struct subre));
n = v->nlacons++;
}
if (v->lacons == NULL) {
ERR(REG_ESPACE);
return 0;
}
sub = &v->lacons[n];
sub->begin = begin;
sub->end = end;
sub->subno = pos;
ZAPCNFA(sub->cnfa);
return n;
}
/*
- freelacons - free lookahead-constraint subRE vector
^ static VOID freelacons(struct subre *, int);
*/
static VOID
freelacons(subs, n)
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 *);
*/
static VOID
rfree(re)
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;
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);
}
/*
- dump - dump an RE in human-readable form
^ static VOID dump(regex_t *, FILE *);
*/
static VOID
dump(re, f)
regex_t *re;
FILE *f;
{
#ifdef REG_DEBUG
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",
re->re_nsub, re->re_info, re->re_csize, g->ntree);
dumpcolors(&g->cmap, f);
if (!NULLCNFA(g->search)) {
printf("\nsearch:\n");
dumpcnfa(&g->search, f);
}
for (i = 1; i < g->nlacons; i++) {
fprintf(f, "\nla%d (%s):\n", i,
(g->lacons[i].subno) ? "positive" : "negative");
dumpcnfa(&g->lacons[i].cnfa, f);
}
fprintf(f, "\n");
dumpst(g->tree, f, 0);
#endif
}
/*
- dumpst - dump a subRE tree
^ static VOID dumpst(struct subre *, FILE *, int);
*/
static VOID
dumpst(t, f, nfapresent)
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 *, FILE *, int);
*/
static VOID
stdump(t, f, nfapresent)
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 != INFINITY)
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 char *stid(struct subre *, char *, size_t);
*/
static char * /* points to buf or constant string */
stid(t, buf, bufsize)
struct subre *t;
char *buf;
size_t bufsize;
{
/* big enough for hex int or decimal t->retry? */
if (bufsize < sizeof(int)*2 + 3 || bufsize < sizeof(t->retry)*3 + 1)
return "unable";
if (t->retry != 0)
sprintf(buf, "%d", t->retry);
else
sprintf(buf, "0x%x", (int)t); /* may lose bits, that's okay */
return buf;
}
#include "regc_lex.c"
#include "regc_color.c"
#include "regc_nfa.c"
#include "regc_cvec.c"
#include "regc_locale.c"