+ * 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.
+ *
+ * $Header: /projects/cvsroot/pgsql-server/src/backend/regex/regexec.c,v 1.23 2003/08/08 21:41:56 momjian Exp $
+ *
+ */
+
+#include "regguts.h"
+
+
+
+/* lazy-DFA representation */
+struct arcp
+{ /* "pointer" to an outarc */
+ struct sset *ss;
+ color co;
+};
+
+struct sset
+{ /* state set */
+ unsigned *states; /* pointer to bitvector */
+ unsigned hash; /* hash of bitvector */
+#define HASH(bv, nw) (((nw) == 1) ? *(bv) : hash(bv, nw))
+#define HIT(h,bv,ss,nw) ((ss)->hash == (h) && ((nw) == 1 || \
+ memcmp(VS(bv), VS((ss)->states), (nw)*sizeof(unsigned)) == 0))
+ int flags;
+#define STARTER 01 /* the initial state set */
+#define POSTSTATE 02 /* includes the goal state */
+#define LOCKED 04 /* locked in cache */
+#define NOPROGRESS 010 /* zero-progress state set */
+ struct arcp ins; /* chain of inarcs pointing here */
+ chr *lastseen; /* last entered on arrival here */
+ struct sset **outs; /* outarc vector indexed by color */
+ struct arcp *inchain; /* chain-pointer vector for outarcs */
+};
+
+struct dfa
+{
+ int nssets; /* size of cache */
+ int nssused; /* how many entries occupied yet */
+ int nstates; /* number of states */
+ int ncolors; /* length of outarc and inchain vectors */
+ int wordsper; /* length of state-set bitvectors */
+ struct sset *ssets; /* state-set cache */
+ unsigned *statesarea; /* bitvector storage */
+ unsigned *work; /* pointer to work area within statesarea */
+ struct sset **outsarea; /* outarc-vector storage */
+ struct arcp *incarea; /* inchain storage */
+ struct cnfa *cnfa;
+ struct colormap *cm;
+ chr *lastpost; /* location of last cache-flushed success */
+ chr *lastnopr; /* location of last cache-flushed
+ * NOPROGRESS */
+ struct sset *search; /* replacement-search-pointer memory */
+ int cptsmalloced; /* were the areas individually malloced? */
+ char *mallocarea; /* self, or master malloced area, or NULL */
+};
+
+#define WORK 1 /* number of work bitvectors needed */
+
+/* setup for non-malloc allocation for small cases */
+#define FEWSTATES 20 /* must be less than UBITS */
+#define FEWCOLORS 15
+struct smalldfa
+{
+ struct dfa dfa;
+ struct sset ssets[FEWSTATES * 2];
+ unsigned statesarea[FEWSTATES * 2 + WORK];
+ struct sset *outsarea[FEWSTATES * 2 * FEWCOLORS];
+ struct arcp incarea[FEWSTATES * 2 * FEWCOLORS];
+};
+
+#define DOMALLOC ((struct smalldfa *)NULL) /* force malloc */
+
+
+
+/* internal variables, bundled for easy passing around */
+struct vars
+{
+ regex_t *re;
+ struct guts *g;
+ int eflags; /* copies of arguments */
+ size_t nmatch;
+ regmatch_t *pmatch;
+ rm_detail_t *details;
+ chr *start; /* start of string */
+ chr *stop; /* just past end of string */
+ int err; /* error code if any (0 none) */
+ regoff_t *mem; /* memory vector for backtracking */
+ struct smalldfa dfa1;
+ struct smalldfa dfa2;
+};
+
+#define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
+#define ISERR() VISERR(v)
+#define VERR(vv,e) (((vv)->err) ? (vv)->err : ((vv)->err = (e)))
+#define ERR(e) VERR(v, e) /* record an error */
+#define NOERR() {if (ISERR()) return v->err;} /* if error seen, return
+ * it */
+#define OFF(p) ((p) - v->start)
+#define LOFF(p) ((long)OFF(p))
+
+
+
+/*
+ * forward declarations
+ */
+/* === regexec.c === */
+static int find(struct vars *, struct cnfa *, struct colormap *);
+static int cfind(struct vars *, struct cnfa *, struct colormap *);
+static int cfindloop(struct vars *, struct cnfa *, struct colormap *, struct dfa *, struct dfa *, chr **);
+static void zapsubs(regmatch_t *, size_t);
+static void zapmem(struct vars *, struct subre *);
+static void subset(struct vars *, struct subre *, chr *, chr *);
+static int dissect(struct vars *, struct subre *, chr *, chr *);
+static int condissect(struct vars *, struct subre *, chr *, chr *);
+static int altdissect(struct vars *, struct subre *, chr *, chr *);
+static int cdissect(struct vars *, struct subre *, chr *, chr *);
+static int ccondissect(struct vars *, struct subre *, chr *, chr *);
+static int crevdissect(struct vars *, struct subre *, chr *, chr *);
+static int cbrdissect(struct vars *, struct subre *, chr *, chr *);
+static int caltdissect(struct vars *, struct subre *, chr *, chr *);
+
+/* === rege_dfa.c === */
+static chr *longest(struct vars *, struct dfa *, chr *, chr *, int *);
+static chr *shortest(struct vars *, struct dfa *, chr *, chr *, chr *, chr **, int *);
+static chr *lastcold(struct vars *, struct dfa *);
+static struct dfa *newdfa(struct vars *, struct cnfa *, struct colormap *, struct smalldfa *);
+static void freedfa(struct dfa *);
+static unsigned hash(unsigned *, int);
+static struct sset *initialize(struct vars *, struct dfa *, chr *);
+static struct sset *miss(struct vars *, struct dfa *, struct sset *, pcolor, chr *, chr *);
+static int lacon(struct vars *, struct cnfa *, chr *, pcolor);
+static struct sset *getvacant(struct vars *, struct dfa *, chr *, chr *);
+static struct sset *pickss(struct vars *, struct dfa *, chr *, chr *);
+
+
+/*
+ * regexec - match regular expression
+ */
+int
+regexec(regex_t *re,
+ const chr *string,
+ size_t nmatch,
+ regmatch_t pmatch[],
+ int flags)
+{
+ rm_detail_t det;
+ size_t nLen = 0;
+ chr* s2 = (chr*) string;
+
+ if (string && *string)
+ {
+ while(*++s2);
+ }
+
+ nLen = ((s2 - string) / sizeof(chr));
+
+ return wx_regexec(re, string, nLen, &det, nmatch, pmatch, flags);
+}
+int
+wx_regexec(regex_t *re,
+ const chr *string,
+ size_t len,
+ rm_detail_t *details,
+ size_t nmatch,
+ regmatch_t pmatch[],
+ int flags)
+{
+ struct vars var;
+ register struct vars *v = &var;
+ int st;
+ size_t n;
+ int backref;
+
+#define LOCALMAT 20
+ regmatch_t mat[LOCALMAT];
+
+#define LOCALMEM 40
+ regoff_t mem[LOCALMEM];
+
+ /* sanity checks */
+ if (re == NULL || string == NULL || re->re_magic != REMAGIC)
+ return REG_INVARG;
+ if (re->re_csize != sizeof(chr))
+ return REG_MIXED;
+
+ /* setup */
+ v->re = re;
+ v->g = (struct guts *) re->re_guts;
+ if ((v->g->cflags & REG_EXPECT) && details == NULL)
+ return REG_INVARG;
+ if (v->g->info & REG_UIMPOSSIBLE)
+ return REG_NOMATCH;
+ backref = (v->g->info & REG_UBACKREF) ? 1 : 0;
+ v->eflags = flags;
+ if (v->g->cflags & REG_NOSUB)
+ nmatch = 0; /* override client */
+ v->nmatch = nmatch;
+ if (backref)
+ {
+ /* need work area */
+ if (v->g->nsub + 1 <= LOCALMAT)
+ v->pmatch = mat;
+ else
+ v->pmatch = (regmatch_t *) MALLOC((v->g->nsub + 1) *
+ sizeof(regmatch_t));
+ if (v->pmatch == NULL)
+ return REG_ESPACE;
+ v->nmatch = v->g->nsub + 1;
+ }
+ else
+ v->pmatch = pmatch;
+ v->details = details;
+ v->start = (chr *) string;
+ v->stop = (chr *) string + len;
+ v->err = 0;
+ if (backref)
+ {
+ /* need retry memory */
+ assert(v->g->ntree >= 0);
+ n = (size_t) v->g->ntree;
+ if (n <= LOCALMEM)
+ v->mem = mem;
+ else
+ v->mem = (regoff_t *) MALLOC(n * sizeof(regoff_t));
+ if (v->mem == NULL)
+ {
+ if (v->pmatch != pmatch && v->pmatch != mat)
+ FREE(v->pmatch);
+ return REG_ESPACE;
+ }
+ }
+ else
+ v->mem = NULL;
+
+ /* do it */
+ assert(v->g->tree != NULL);
+ if (backref)
+ st = cfind(v, &v->g->tree->cnfa, &v->g->cmap);
+ else
+ st = find(v, &v->g->tree->cnfa, &v->g->cmap);
+
+ /* copy (portion of) match vector over if necessary */
+ if (st == REG_OKAY && v->pmatch != pmatch && nmatch > 0)
+ {
+ zapsubs(pmatch, nmatch);
+ n = (nmatch < v->nmatch) ? nmatch : v->nmatch;
+ memcpy(VS(pmatch), VS(v->pmatch), n * sizeof(regmatch_t));
+ }
+
+ /* clean up */
+ if (v->pmatch != pmatch && v->pmatch != mat)
+ FREE(v->pmatch);
+ if (v->mem != NULL && v->mem != mem)
+ FREE(v->mem);
+ return st;
+}
+
+/*
+ * find - find a match for the main NFA (no-complications case)
+ */
+static int
+find(struct vars * v,
+ struct cnfa * cnfa,
+ struct colormap * cm)
+{
+ struct dfa *s;
+ struct dfa *d;
+ chr *begin;
+ chr *end = NULL;
+ chr *cold;
+ chr *open; /* open and close of range of possible
+ * starts */
+ chr *close;
+ int hitend;
+ int shorter = (v->g->tree->flags & SHORTER) ? 1 : 0;
+
+ /* first, a shot with the search RE */
+ s = newdfa(v, &v->g->search, cm, &v->dfa1);
+ assert(!(ISERR() && s != NULL));
+ NOERR();
+ MDEBUG(("\nsearch at %ld\n", LOFF(v->start)));
+ cold = NULL;
+ close = shortest(v, s, v->start, v->start, v->stop, &cold, (int *) NULL);
+ freedfa(s);
+ NOERR();
+ if (v->g->cflags & REG_EXPECT)
+ {
+ assert(v->details != NULL);
+ if (cold != NULL)
+ v->details->rm_extend.rm_so = OFF(cold);
+ else
+ v->details->rm_extend.rm_so = OFF(v->stop);
+ v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
+ }
+ if (close == NULL) /* not found */
+ return REG_NOMATCH;
+ if (v->nmatch == 0) /* found, don't need exact location */
+ return REG_OKAY;
+
+ /* find starting point and match */
+ assert(cold != NULL);
+ open = cold;
+ cold = NULL;
+ MDEBUG(("between %ld and %ld\n", LOFF(open), LOFF(close)));
+ d = newdfa(v, cnfa, cm, &v->dfa1);
+ assert(!(ISERR() && d != NULL));
+ NOERR();
+ for (begin = open; begin <= close; begin++)
+ {
+ MDEBUG(("\nfind trying at %ld\n", LOFF(begin)));
+ if (shorter)
+ end = shortest(v, d, begin, begin, v->stop,
+ (chr **) NULL, &hitend);
+ else
+ end = longest(v, d, begin, v->stop, &hitend);
+ NOERR();
+ if (hitend && cold == NULL)
+ cold = begin;
+ if (end != NULL)
+ break; /* NOTE BREAK OUT */
+ }
+ assert(end != NULL); /* search RE succeeded so loop should */
+ freedfa(d);
+
+ /* and pin down details */
+ assert(v->nmatch > 0);
+ v->pmatch[0].rm_so = OFF(begin);
+ v->pmatch[0].rm_eo = OFF(end);
+ if (v->g->cflags & REG_EXPECT)
+ {
+ if (cold != NULL)
+ v->details->rm_extend.rm_so = OFF(cold);
+ else
+ v->details->rm_extend.rm_so = OFF(v->stop);
+ v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
+ }
+ if (v->nmatch == 1) /* no need for submatches */
+ return REG_OKAY;
+
+ /* submatches */
+ zapsubs(v->pmatch, v->nmatch);
+ return dissect(v, v->g->tree, begin, end);
+}
+
+/*
+ * cfind - find a match for the main NFA (with complications)
+ */
+static int
+cfind(struct vars * v,
+ struct cnfa * cnfa,
+ struct colormap * cm)
+{
+ struct dfa *s;
+ struct dfa *d;
+ chr *cold;
+ int ret;
+
+ s = newdfa(v, &v->g->search, cm, &v->dfa1);
+ NOERR();
+ d = newdfa(v, cnfa, cm, &v->dfa2);
+ if (ISERR())
+ {
+ assert(d == NULL);
+ freedfa(s);
+ return v->err;
+ }
+
+ ret = cfindloop(v, cnfa, cm, d, s, &cold);
+
+ freedfa(d);
+ freedfa(s);
+ NOERR();
+ if (v->g->cflags & REG_EXPECT)
+ {
+ assert(v->details != NULL);
+ if (cold != NULL)
+ v->details->rm_extend.rm_so = OFF(cold);
+ else
+ v->details->rm_extend.rm_so = OFF(v->stop);
+ v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
+ }
+ return ret;
+}
+
+/*
+ * cfindloop - the heart of cfind
+ */
+static int
+cfindloop(struct vars * v,
+ struct cnfa * cnfa,
+ struct colormap * cm,
+ struct dfa * d,
+ struct dfa * s,
+ chr **coldp) /* where to put coldstart pointer */
+{
+ chr *begin;
+ chr *end;
+ chr *cold;
+ chr *open; /* open and close of range of possible
+ * starts */
+ chr *close;
+ chr *estart;
+ chr *estop;
+ int er;
+ int shorter = v->g->tree->flags & SHORTER;
+ int hitend;
+
+ assert(d != NULL && s != NULL);
+ cold = NULL;
+ close = v->start;
+ do
+ {
+ MDEBUG(("\ncsearch at %ld\n", LOFF(close)));
+ close = shortest(v, s, close, close, v->stop, &cold, (int *) NULL);
+ if (close == NULL)
+ break; /* NOTE BREAK */
+ assert(cold != NULL);
+ open = cold;
+ cold = NULL;
+ MDEBUG(("cbetween %ld and %ld\n", LOFF(open), LOFF(close)));
+ for (begin = open; begin <= close; begin++)
+ {
+ MDEBUG(("\ncfind trying at %ld\n", LOFF(begin)));
+ estart = begin;
+ estop = v->stop;
+ for (;;)
+ {
+ if (shorter)
+ end = shortest(v, d, begin, estart,
+ estop, (chr **) NULL, &hitend);
+ else
+ end = longest(v, d, begin, estop,
+ &hitend);
+ if (hitend && cold == NULL)
+ cold = begin;
+ if (end == NULL)
+ break; /* NOTE BREAK OUT */
+ MDEBUG(("tentative end %ld\n", LOFF(end)));
+ zapsubs(v->pmatch, v->nmatch);
+ zapmem(v, v->g->tree);
+ er = cdissect(v, v->g->tree, begin, end);
+ if (er == REG_OKAY)
+ {
+ if (v->nmatch > 0)
+ {
+ v->pmatch[0].rm_so = OFF(begin);
+ v->pmatch[0].rm_eo = OFF(end);
+ }
+ *coldp = cold;
+ return REG_OKAY;
+ }
+ if (er != REG_NOMATCH)
+ {
+ ERR(er);
+ return er;
+ }
+ if ((shorter) ? end == estop : end == begin)
+ {
+ /* no point in trying again */
+ *coldp = cold;
+ return REG_NOMATCH;
+ }
+ /* go around and try again */
+ if (shorter)
+ estart = end + 1;
+ else
+ estop = end - 1;
+ }
+ }
+ } while (close < v->stop);
+
+ *coldp = cold;
+ return REG_NOMATCH;
+}
+
+/*
+ * zapsubs - initialize the subexpression matches to "no match"
+ */
+static void
+zapsubs(regmatch_t *p,
+ size_t n)
+{
+ size_t i;
+
+ for (i = n - 1; i > 0; i--)
+ {
+ p[i].rm_so = -1;
+ p[i].rm_eo = -1;
+ }
+}
+
+/*
+ * zapmem - initialize the retry memory of a subtree to zeros
+ */
+static void
+zapmem(struct vars * v,
+ struct subre * t)
+{
+ if (t == NULL)
+ return;
+
+ assert(v->mem != NULL);
+ v->mem[t->retry] = 0;
+ if (t->op == '(')
+ {
+ assert(t->subno > 0);
+ v->pmatch[t->subno].rm_so = -1;
+ v->pmatch[t->subno].rm_eo = -1;
+ }
+
+ if (t->left != NULL)
+ zapmem(v, t->left);
+ if (t->right != NULL)
+ zapmem(v, t->right);
+}
+
+/*
+ * subset - set any subexpression relevant to a successful subre
+ */
+static void
+subset(struct vars * v,
+ struct subre * sub,
+ chr *begin,
+ chr *end)
+{
+ int n = sub->subno;
+
+ assert(n > 0);
+ if ((size_t) n >= v->nmatch)
+ return;
+
+ MDEBUG(("setting %d\n", n));
+ v->pmatch[n].rm_so = OFF(begin);
+ v->pmatch[n].rm_eo = OFF(end);
+}
+
+/*
+ * dissect - determine subexpression matches (uncomplicated case)
+ */
+static int /* regexec return code */
+dissect(struct vars * v,
+ struct subre * t,
+ chr *begin, /* beginning of relevant substring */
+ chr *end) /* end of same */
+{
+ assert(t != NULL);
+ MDEBUG(("dissect %ld-%ld\n", LOFF(begin), LOFF(end)));
+
+ switch (t->op)
+ {
+ case '=': /* terminal node */
+ assert(t->left == NULL && t->right == NULL);
+ return REG_OKAY; /* no action, parent did the work */
+ break;
+ case '|': /* alternation */
+ assert(t->left != NULL);
+ return altdissect(v, t, begin, end);
+ break;
+ case 'b': /* back ref -- shouldn't be calling us! */
+ return REG_ASSERT;
+ break;
+ case '.': /* concatenation */
+ assert(t->left != NULL && t->right != NULL);
+ return condissect(v, t, begin, end);
+ break;
+ case '(': /* capturing */
+ assert(t->left != NULL && t->right == NULL);
+ assert(t->subno > 0);
+ subset(v, t, begin, end);
+ return dissect(v, t->left, begin, end);
+ break;
+ default:
+ return REG_ASSERT;
+ break;
+ }
+}
+
+/*
+ * condissect - determine concatenation subexpression matches (uncomplicated)
+ */
+static int /* regexec return code */
+condissect(struct vars * v,
+ struct subre * t,
+ chr *begin, /* beginning of relevant substring */
+ chr *end) /* end of same */
+{
+ struct dfa *d;
+ struct dfa *d2;
+ chr *mid;
+ int i;
+ int shorter = (t->left->flags & SHORTER) ? 1 : 0;
+ chr *stop = (shorter) ? end : begin;
+
+ assert(t->op == '.');
+ assert(t->left != NULL && t->left->cnfa.nstates > 0);
+ assert(t->right != NULL && t->right->cnfa.nstates > 0);
+
+ d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
+ NOERR();
+ d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, &v->dfa2);
+ if (ISERR())
+ {
+ assert(d2 == NULL);
+ freedfa(d);
+ return v->err;
+ }
+
+ /* pick a tentative midpoint */
+ if (shorter)
+ mid = shortest(v, d, begin, begin, end, (chr **) NULL,
+ (int *) NULL);
projects / wxWidgets.git / blobdiff