add musl and vi

1 files changed, 877 insertions, 0 deletions

diff --git a/libuxre/regdfa.c b/libuxre/regdfa.c
new file mode 100644
index 0000000..8142e8d
--- /dev/null
+++ b/libuxre/regdfa.c
@@ -0,0 +1,877 @@
+/*
+ * Changes by Gunnar Ritter, Freiburg i. Br., Germany, November 2002.
+ *
+ * Sccsid @(#)regdfa.c	1.9 (gritter) 9/22/03
+ */
+/*  UNIX(R) Regular Expresssion Library
+ *
+ *  Note: Code is released under the GNU LGPL
+ *
+ *  Copyright (C) 2001 Caldera International, Inc.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to:
+ *        Free Software Foundation, Inc.
+ *        59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*	#include "synonyms.h"	*/
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include "regdfa.h"
+
+/*
+* Deterministic Finite Automata.
+*/
+
+	/*
+	* Postorder traversal that returns a copy of the subtree,
+	* except that ROP_BKT becomes ROP_BKTCOPY (since they
+	* share the same pointed to Bracket object).
+	*/
+static Tree *
+copy(regex_t *ep, Tree *tp)
+{
+	Tree *np;
+
+	if ((np = malloc(sizeof(Tree))) == 0)
+		return 0;
+	switch (np->op = tp->op) /* almost always correct */
+	{
+	case ROP_BKT:
+		np->op = ROP_BKTCOPY;
+		/*FALLTHROUGH*/
+	case ROP_BKTCOPY:
+		np->right.info.bkt = tp->right.info.bkt;
+		/*FALLTHROUGH*/
+	default:
+		np->left.pos = ep->re_dfa->nposn++;
+		/*FALLTHROUGH*/
+	case ROP_EMPTY:
+		return np;
+	case ROP_CAT:
+	case ROP_OR:
+		if ((np->right.ptr = copy(ep, tp->right.ptr)) == 0)
+		{
+			free(np);
+			return 0;
+		}
+		np->right.ptr->parent = np;
+		/*FALLTHROUGH*/
+	case ROP_STAR:
+	case ROP_PLUS:
+	case ROP_QUEST:
+	case ROP_LP:
+		if ((np->left.ptr = copy(ep, tp->left.ptr)) == 0)
+			break;
+		np->left.ptr->parent = np;
+		return np;
+	}
+	libuxre_regdeltree(np, 1);
+	return 0;
+}
+
+	/*
+	* Postorder traversal.
+	* Assign unique ascending integer values to the leaves.
+	* Since the right child is traversed before the left,
+	* the position for ROP_END is guaranteed to be zero.
+	* The parse tree is rewritten in two cases:
+	* - Each ROP_BRACE is replaced by an equivalent--sometimes
+	*   large--subtree using only ROP_CAT, ROP_QUEST, and
+	*   ROP_PLUS.
+	* - If REG_ICASE, replace each simple character that has
+	*   an uppercase equivalent with a ROP_OR subtree over the
+	*   two versions.
+	* Since these rewrites occur bottom up, they have already
+	* been applied before any subtrees passed to copy().
+	*/
+static Tree *
+findposn(regex_t *ep, Tree *tp, int mb_cur_max)
+{
+	unsigned int lo, hi;
+	Tree *ptr, *par;
+	w_type wc;
+
+	switch (tp->op)
+	{
+	default:
+		if (ep->re_flags & REG_ICASE
+			&& (wc = to_upper(tp->op)) != tp->op)
+		{
+			if ((ptr = libuxre_reg1tree(tp->op, 0)) == 0)
+				return 0;
+			ptr->parent = tp;
+			ptr->left.pos = ep->re_dfa->nposn++;
+			tp->op = ROP_OR;
+			tp->left.ptr = ptr;
+			ptr = libuxre_reg1tree(wc, 0);
+			if ((tp->right.ptr = ptr) == 0)
+				return 0;
+			ptr->parent = tp;
+			ptr->left.pos = ep->re_dfa->nposn++;
+			return tp;
+		}
+		/*FALLTHROUGH*/
+	case ROP_BOL:
+	case ROP_EOL:
+	case ROP_ALL:
+	case ROP_ANYCH:
+	case ROP_NOTNL:
+	case ROP_NONE:
+	case ROP_BKT:
+	case ROP_BKTCOPY:
+	case ROP_END:
+		tp->left.pos = ep->re_dfa->nposn++;
+		return tp;
+	case ROP_EMPTY:
+		return tp;
+	case ROP_OR:
+	case ROP_CAT:
+		if ((tp->right.ptr = findposn(ep, tp->right.ptr,
+						mb_cur_max)) == 0)
+			return 0;
+		/*FALLTHROUGH*/
+	case ROP_STAR:
+	case ROP_PLUS:
+	case ROP_QUEST:
+	case ROP_LP:
+		if ((tp->left.ptr = findposn(ep, tp->left.ptr,
+						mb_cur_max)) == 0)
+			return 0;
+		return tp;
+	case ROP_BRACE:
+		if ((tp->left.ptr = findposn(ep, tp->left.ptr,
+						mb_cur_max)) == 0)
+			return 0;
+		break;
+	}
+	/*
+	* ROP_BRACE as is cannot be handled in a DFA.  This code
+	* duplicates the ROP_BRACE subtree as a left-towering
+	* series of ROP_CAT nodes, the first "lo" of which are
+	* direct copies of the original subtree.  The tail of
+	* the series are either some number of ROP_QUESTs over
+	* copies of the original subtree, or a single ROP_PLUS
+	* over a copy (when "hi" is infinity).
+	*
+	* All interesting cases {lo,hi}:
+	*  {0,0} -> ROP_EMPTY, parsing, temporary
+	*  {0,1} -> ROP_QUEST, parsing
+	*  {0,2} -> CAT(QUEST(left), QUEST(copy))
+	*  {0,n} -> CAT({0,n-1}, QUEST(copy))
+	*  {0,}  -> ROP_STAR, parsing
+	*
+	*  {1,1} -> ROP_NOP, parsing, temporary
+	*  {1,2} -> CAT(left, QUEST(copy))
+	*  {1,n} -> CAT({1,n-1}, QUEST(copy))
+	*  {1,}  -> ROP_PLUS, parsing
+	*
+	*  {2,2} -> CAT(left, copy)
+	*  {2,n} -> CAT({2,n-1}, QUEST(copy))
+	*  {2,}  -> CAT(left, PLUS(copy))
+	*
+	*  {3,3} -> CAT({2,2}, copy)
+	*  {3,n} -> CAT({3,n-1}, QUEST(copy))
+	*  {3,}  -> CAT({2,2}, PLUS(copy))
+	*
+	*  {n,}  -> CAT({n-1,n-1}, PLUS(copy))
+	*
+	* In all cases, the ROP_BRACE node is turned into the
+	* left-most ROP_CAT, and a copy of its original subtree
+	* is connected as the right child.  Note that the bottom-
+	* up nature of this duplication guarantees that copy()
+	* never sees a ROP_BRACE node.
+	*/
+	par = tp->parent;
+	lo = tp->right.info.num[0];
+	hi = tp->right.info.num[1];
+	if ((ptr = copy(ep, tp->left.ptr)) == 0)
+		return 0;
+	ptr->parent = tp;
+	tp->op = ROP_CAT;
+	tp->right.ptr = ptr;
+	if (lo == 0)
+	{
+		if ((tp->left.ptr = libuxre_reg1tree(ROP_QUEST, tp->left.ptr))
+				== 0)
+			return 0;
+		tp->left.ptr->parent = tp;
+	}
+	else
+	{
+		if (hi == BRACE_INF || (hi -= lo) == 0)
+			lo--;	/* lo > 1; no extra needed */
+		while (--lo != 0)
+		{
+			if ((tp = libuxre_reg2tree(ROP_CAT, tp, copy(ep, ptr)))
+					== 0)
+				return 0;
+		}
+	}
+	if (hi == BRACE_INF)
+	{
+		if ((tp->right.ptr = libuxre_reg1tree(ROP_PLUS, tp->right.ptr))
+				== 0)
+			return 0;
+		tp->right.ptr->parent = tp;
+	}
+	else if (hi != 0)
+	{
+		if ((tp->right.ptr = libuxre_reg1tree(ROP_QUEST, tp->right.ptr))
+				== 0)
+			return 0;
+		ptr = tp->right.ptr;
+		ptr->parent = tp;
+		while (--hi != 0)
+		{
+			if ((tp = libuxre_reg2tree(ROP_CAT, tp, copy(ep, ptr)))
+					== 0)
+				return 0;
+		}
+	}
+	tp->parent = par;
+	return tp;
+}
+
+	/*
+	* Postorder traversal, but not always entire subtree.
+	* For each leaf reachable by the empty string, add it
+	* to the set.  Return 0 if the subtree can match empty.
+	*/
+static int
+first(Dfa *dp, Tree *tp)
+{
+	switch (tp->op)
+	{
+	case ROP_BOL:
+		if (dp->flags & REG_NOTBOL)
+			return 0;
+		break;
+	case ROP_EOL:
+		if (dp->flags & REG_NOTEOL)
+			return 0;
+		break;
+	case ROP_EMPTY:
+		return 0;
+	case ROP_OR:
+		return first(dp, tp->left.ptr) & first(dp, tp->right.ptr);
+	case ROP_CAT:
+		if (first(dp, tp->left.ptr) != 0)
+			return 1;
+		return first(dp, tp->right.ptr);
+	case ROP_BRACE:
+		if (tp->right.info.num[0] != 0 && first(dp, tp->left.ptr) != 0)
+			return 1;
+		/*FALLTHROUGH*/
+	case ROP_STAR:
+	case ROP_QUEST:
+		first(dp, tp->left.ptr);
+		return 0;
+	case ROP_LP:
+	case ROP_PLUS:
+		return first(dp, tp->left.ptr);
+	}
+	if (dp->posset[tp->left.pos] == 0)
+	{
+		dp->posset[tp->left.pos] = 1;
+		dp->nset++;
+	}
+	return 1;
+}
+
+	/*
+	* Walk from leaf up (most likely not to root).
+	* Determine follow set for the leaf by filling
+	* set[] with the positions reachable.
+	*/
+static void
+follow(Dfa *dp, Tree *tp)
+{
+	Tree *pp;
+
+	switch ((pp = tp->parent)->op)
+	{
+	case ROP_CAT:
+		if (pp->left.ptr == tp && first(dp, pp->right.ptr) != 0)
+			break;
+		/*FALLTHROUGH*/
+	case ROP_OR:
+	case ROP_QUEST:
+	case ROP_LP:
+		follow(dp, pp);
+		break;
+	case ROP_STAR:
+	case ROP_PLUS:
+	case ROP_BRACE:
+		first(dp, tp);
+		follow(dp, pp);
+		break;
+	}
+}
+
+	/*
+	* Postorder traversal.
+	* At each leaf, copy it into posn[] and assign its follow set.
+	* Because the left-most subtree is ROP_ALL under ROP_STAR, the
+	* follow set for its leaf (position dp->nposn-1) is the same
+	* as the initial state's signature (prior to any ROP_BOL).
+	*/
+static int
+posnfoll(Dfa *dp, Tree *tp)
+{
+	unsigned char *s;
+	size_t i, n;
+	size_t *fp;
+	Posn *p;
+	int ret;
+
+	switch (tp->op)
+	{
+	case ROP_OR:
+	case ROP_CAT:
+		if ((ret = posnfoll(dp, tp->right.ptr)) != 0)
+			return ret;
+		/*FALLTHROUGH*/
+	case ROP_STAR:
+	case ROP_PLUS:
+	case ROP_QUEST:
+	case ROP_LP:
+		if ((ret = posnfoll(dp, tp->left.ptr)) != 0)
+			return ret;
+		return 0;
+	case ROP_END:	/* keeps follow() from walking above the root */
+		p = &dp->posn[tp->left.pos];
+		p->op = tp->op;
+		p->seti = 0;
+		p->nset = 0;
+		return 0;
+	case ROP_BKT:
+	case ROP_BKTCOPY:
+		p = &dp->posn[tp->left.pos];
+		p->bkt = tp->right.info.bkt;
+		goto skip;
+	case ROP_BOL:
+		dp->flags |= REG_NOTBOL; /* adjacent ROP_BOLs match empty */
+		break;
+	case ROP_EOL:
+		dp->flags |= REG_NOTEOL; /* adjacent ROP_EOLs match empty */
+		break;
+	}
+	p = &dp->posn[tp->left.pos];
+skip:;
+	p->op = tp->op;
+	memset(dp->posset, 0, dp->nposn);
+	dp->nset = 0;
+	follow(dp, tp);
+	dp->flags &= ~(REG_NOTBOL | REG_NOTEOL);
+	fp = dp->posfoll;
+	if ((p->nset = dp->nset) > dp->avail) /* need more */
+	{
+		if ((n = p->nset << 1) < dp->nposn)
+			n = dp->nposn;	
+		dp->avail += n;
+		if ((fp = realloc(dp->posfoll,
+			sizeof(size_t) * (dp->avail + dp->used))) == 0)
+		{
+			return REG_ESPACE;
+		}
+		dp->posfoll = fp;
+	}
+	p->seti = dp->used;
+	if ((i = dp->nset) != 0)
+	{
+		dp->used += i;
+		dp->avail -= i;
+		fp += p->seti;
+		s = dp->posset;
+		n = 0;
+		do
+		{
+			if (*s++ != 0)
+			{
+				*fp++ = n;
+				if (--i == 0)
+					break;
+			}
+		} while (++n != dp->nposn);
+	}
+	return 0;
+}
+
+static int
+addstate(Dfa *dp) /* install state if unique; return its index */
+{
+	size_t *sp, *fp;
+	size_t t, n, i;
+	int flushed;
+
+	/*
+	* Compare dp->nset/dp->cursig[] against remembered states.
+	*/
+	t = dp->top;
+	do
+	{
+		if (dp->nsig[--t] != dp->nset)
+			continue;
+		if ((n = dp->nset) != 0)
+		{
+			fp = &dp->sigfoll[dp->sigi[t]];
+			sp = &dp->cursig[0];
+		loop:;
+			if (*fp++ != *sp++)
+				continue; /* to the do-while */
+			if (--n != 0)
+				goto loop;
+		}
+		return t + 1;
+	} while (t != 0);
+	/*
+	* Not in currently cached states; add it.
+	*/
+	flushed = 0;
+	if ((t = dp->top) >= CACHESZ)	/* need to flush the cache */
+	{
+		flushed = 1;
+		n = dp->anybol;
+		n = dp->sigi[n] + dp->nsig[n];	/* past invariant states */
+		dp->avail += dp->used - n;
+		dp->used = n;
+		dp->top = n = dp->nfix;
+		memset((void *)&dp->trans, 0, sizeof(dp->trans));
+		memset((void *)&dp->acc[n], 0, CACHESZ - n);
+		t = n;
+	}
+	dp->top++;
+	fp = dp->sigfoll;
+	if ((n = dp->nset) > dp->avail)	/* grow strip */
+	{
+		i = dp->avail + n << 1;
+		if ((fp = realloc(fp, sizeof(size_t) * (i + dp->used))) == 0)
+			return 0;
+		dp->avail = i;
+		dp->sigfoll = fp;
+	}
+	dp->acc[t] = 0;
+	if ((dp->nsig[t] = n) != 0)
+	{
+		sp = dp->cursig;
+		if (sp[0] == 0)
+			dp->acc[t] = 1;
+		dp->sigi[t] = i = dp->used;
+		dp->used += n;
+		dp->avail -= n;
+		fp += i;
+		do
+			*fp++ = *sp++;
+		while (--n != 0);
+	}
+	t++;
+	if (flushed)
+		return -t;
+	return t;
+}
+
+void
+libuxre_regdeldfa(Dfa *dp)
+{
+	Posn *pp;
+	size_t np;
+
+	if (dp->posfoll != 0)
+		free(dp->posfoll);
+	if (dp->sigfoll != 0)
+		free(dp->sigfoll);
+	if (dp->cursig != 0)
+		free(dp->cursig);
+	if ((pp = dp->posn) != 0)
+	{
+		/*
+		* Need to walk the positions list to free any
+		* space used for ROP_BKTs.
+		*/
+		np = dp->nposn;
+		do
+		{
+			if (pp->op == ROP_BKT)
+			{
+				libuxre_bktfree(pp->bkt);
+				free(pp->bkt);
+			}
+		} while (++pp, --np != 0);
+		free(dp->posn);
+	}
+	free(dp);
+}
+
+int
+regtrans(Dfa *dp, int st, w_type wc, int mb_cur_max)
+{
+	const unsigned char *s;
+	size_t *fp, *sp;
+	size_t i, n;
+	Posn *pp;
+	int nst;
+
+	if ((n = dp->nsig[st]) == 0)	/* dead state */
+		return st + 1;		/* stay here */
+	memset(dp->posset, 0, dp->nposn);
+	dp->nset = 0;
+	fp = &dp->sigfoll[dp->sigi[st]];
+	do
+	{
+		pp = &dp->posn[*fp];
+		switch (pp->op)
+		{
+		case ROP_EOL:
+			if (wc == '\0' && (dp->flags & REG_NOTEOL) == 0)
+				break;
+			/*FALLTHROUGH*/
+		case ROP_BOL:
+		default:
+			if (pp->op == wc)
+				break;
+			/*FALLTHROUGH*/
+		case ROP_END:
+		case ROP_NONE:
+			continue;
+		case ROP_NOTNL:
+			if (wc == '\n')
+				continue;
+			/*FALLTHROUGH*/
+		case ROP_ANYCH:
+			if (wc <= '\0')
+				continue;
+			break;
+		case ROP_ALL:
+			if (wc == '\0')
+				continue;
+			break;
+		case ROP_BKT:
+		case ROP_BKTCOPY:
+			/*
+			* Note that multiple character bracket matches
+			* are precluded from DFAs.  (See regparse.c and
+			* regcomp.c.)  Thus, the continuation string
+			* argument is not used in libuxre_bktmbexec().
+			*/
+			if (wc > '\0' &&
+			    libuxre_bktmbexec(pp->bkt, wc, 0, mb_cur_max) == 0)
+				break;
+			continue;
+		}
+		/*
+		* Current character matches this position.
+		* For each position in its follow list,
+		* add that position to the new state's signature.
+		*/
+		i = pp->nset;
+		sp = &dp->posfoll[pp->seti];
+		do
+		{
+			if (dp->posset[*sp] == 0)
+			{
+				dp->posset[*sp] = 1;
+				dp->nset++;
+			}
+		} while (++sp, --i != 0);
+	} while (++fp, --n != 0);
+	/*
+	* Move the signature (if any) into cursig[] and install it.
+	*/
+	if ((i = dp->nset) != 0)
+	{
+		fp = dp->cursig;
+		s = dp->posset;
+		for (n = 0;; n++)
+		{
+			if (*s++ != 0)
+			{
+				*fp++ = n;
+				if (--i == 0)
+					break;
+			}
+		}
+	}
+	if ((nst = addstate(dp)) < 0) /* flushed cache */
+		nst = -nst;
+	else if (nst > 0 && (wc & ~(long)(NCHAR - 1)) == 0)
+		dp->trans[st][wc] = nst;
+	return nst;
+}
+
+LIBUXRE_STATIC int
+libuxre_regdfacomp(regex_t *ep, Tree *tp, Lex *lxp)
+{
+	Tree *lp;
+	Dfa *dp;
+	Posn *p;
+	int st;
+
+	/*
+	* It's convenient to insert an STAR(ALL) subtree to the
+	* immediate left of the current tree.  This makes the
+	* "any match" libuxre_regdfaexec() not a special case,
+	* and the initial state signature will fall out when
+	* building the follow sets for all the leaves.
+	*/
+	if ((lp = libuxre_reg1tree(ROP_ALL, 0)) == 0
+		|| (lp = libuxre_reg1tree(ROP_STAR, lp)) == 0
+		|| (tp->left.ptr = lp
+			= libuxre_reg2tree(ROP_CAT, lp, tp->left.ptr)) == 0)
+	{
+		return REG_ESPACE;
+	}
+	lp->parent = tp;
+	if ((dp = calloc(1, sizeof(Dfa))) == 0)
+		return REG_ESPACE;
+	ep->re_dfa = dp;
+	/*
+	* Just in case null pointers aren't just all bits zero...
+	*/
+	dp->posfoll = 0;
+	dp->sigfoll = 0;
+	dp->cursig = 0;
+	dp->posn = 0;
+	/*
+	* Assign position values to each of the tree's leaves
+	* (the important parts), meanwhile potentially rewriting
+	* the parse tree so that it fits within the restrictions
+	* of our DFA.
+	*/
+	if ((tp = findposn(ep, tp, lxp->mb_cur_max)) == 0)
+		goto err;
+	/*
+	* Get space for the array of positions and current set,
+	* now that the number of positions is known.
+	*/
+	if ((dp->posn = malloc(sizeof(Posn) * dp->nposn + dp->nposn)) == 0)
+		goto err;
+	dp->posset = (unsigned char *)&dp->posn[dp->nposn];
+	/*
+	* Get follow sets for each position.
+	*/
+	if (posnfoll(dp, tp) != 0)
+		goto err;
+	/*
+	* Set up the special invariant states:
+	*  - dead state (no valid transitions); index 0.
+	*  - initial state for any match [STAR(ALL) follow set]; index 1.
+	*  - initial state for any match after ROP_BOL.
+	*  - initial state for left-most longest if REG_NOTBOL.
+	*  - initial state for left-most longest after ROP_BOL.
+	* The final two are not allocated if leftmost() cannot be called.
+	* The pairs of initial states are the same if there is no
+	* explicit ROP_BOL transition.
+	*/
+	dp->avail += dp->used;
+	dp->used = 0;
+	if ((dp->sigfoll = malloc(sizeof(size_t) * dp->avail)) == 0)
+		goto err;
+	p = &dp->posn[dp->nposn - 1];	/* same as first(root) */
+	dp->cursig = &dp->posfoll[p->seti];
+	dp->nset = p->nset;
+	dp->top = 1;	/* index 0 is dead state */
+	addstate(dp);	/* must be state index 1 (returns 2) */
+	if ((dp->cursig = malloc(sizeof(size_t) * dp->nposn)) == 0)
+		goto err;
+	dp->nfix = 2;
+	if ((st = regtrans(dp, 1, ROP_BOL, lxp->mb_cur_max)) == 0)
+		goto err;
+	if ((dp->anybol = st - 1) == 2) /* new state */
+		dp->nfix = 3;
+	if ((ep->re_flags & REG_NOSUB) == 0) /* leftmost() might be called */
+	{
+		/*
+		* leftmost() initial states are the same as the
+		* "any match" ones without the STAR(ALL) position.
+		*/
+		dp->sigi[dp->nfix] = 0;
+		dp->nsig[dp->nfix] = dp->nsig[1] - 1;
+		dp->acc[dp->nfix] = dp->acc[1];
+		dp->leftbol = dp->leftmost = dp->nfix;
+		dp->nfix++;
+		if (dp->anybol != 1)	/* distinct state w/BOL */
+		{
+			dp->sigi[dp->nfix] = dp->sigi[2];
+			dp->nsig[dp->nfix] = dp->nsig[2] - 1;
+			dp->acc[dp->nfix] = dp->acc[2];
+			dp->leftbol = dp->nfix;
+			dp->nfix++;
+		}
+		dp->top = dp->nfix;
+	}
+	return 0;
+err:;
+	libuxre_regdeldfa(dp);
+	return REG_ESPACE;
+}
+
+static int
+leftmost(Dfa *dp, Exec *xp)
+{
+	const unsigned char *s, *beg, *end;
+	int i, nst, st, mb_cur_max;
+	w_type wc;
+
+	mb_cur_max = xp->mb_cur_max;
+	beg = s = xp->str;
+	end = 0;
+	st = dp->leftbol;
+	if (xp->flags & REG_NOTBOL)
+		st = dp->leftmost;
+	if (dp->acc[st] && (xp->flags & REG_NONEMPTY) == 0)
+		end = s;	/* initial empty match allowed */
+	for (;;)
+	{
+		if ((wc = *s++) == '\n')
+		{
+			if (xp->flags & REG_NEWLINE)
+				wc = ROP_EOL;
+		}
+		else if (!ISONEBYTE(wc) && (i = libuxre_mb2wc(&wc, s)) > 0)
+			s += i;
+		if ((wc & ~(long)(NCHAR - 1)) != 0
+			|| (nst = dp->trans[st][wc]) == 0)
+		{
+			if ((nst=regtrans(dp, st, wc, mb_cur_max)) == 0)
+				return REG_ESPACE;
+			if (wc == ROP_EOL) /* REG_NEWLINE only */
+			{
+				if (dp->acc[nst - 1])
+				{
+					if (end == 0 || end < s)
+						end = s;
+					break;
+				}
+				beg = s;
+				st = dp->leftbol;
+				goto newst;
+			}
+		}
+		if ((st = nst - 1) == 0) /* dead state */
+		{
+			if (end != 0)
+				break;
+			if ((wc = *beg++) == '\0')
+				return REG_NOMATCH;
+			else if (!ISONEBYTE(wc) &&
+					(i = libuxre_mb2wc(&wc, beg)) > 0)
+				beg += i;
+			s = beg;
+			st = dp->leftmost;
+			goto newst;
+		}
+		if (wc == '\0')
+		{
+			if (dp->acc[st])
+			{
+				s--;	/* don't include \0 */
+				if (end == 0 || end < s)
+					end = s;
+				break;
+			}
+			if (end != 0)
+				break;
+			return REG_NOMATCH;
+		}
+	newst:;
+		if (dp->acc[st])
+		{
+			if (end == 0 || end < s)
+				end = s;
+		}
+	}
+	xp->match[0].rm_so = beg - xp->str;
+	xp->match[0].rm_eo = end - xp->str;
+	return 0;
+}
+
+/*
+* Optimization by simplification: singlebyte locale and REG_NEWLINE not set.
+* Performance gain for grep is 25% so it's worth the hack.
+*/
+static int
+regdfaexec_opt(Dfa *dp, Exec *xp)
+{
+	const unsigned char *s;
+	int nst, st;
+
+	s = xp->str;
+	st = dp->anybol;
+	if (xp->flags & REG_NOTBOL)
+		st = 1;
+	if (dp->acc[st] && (xp->flags & REG_NONEMPTY) == 0)
+		return 0;	/* initial empty match allowed */
+	do
+	{
+		if ((nst = dp->trans[st][*s]) == 0)
+		{
+			if ((nst = regtrans(dp, st, *s, 1)) == 0)
+				return REG_ESPACE;
+		}
+		if (dp->acc[st = nst - 1])
+			return 0;
+	} while (*s++ != '\0');	/* st != 0 */
+	return REG_NOMATCH;
+}
+
+LIBUXRE_STATIC int
+libuxre_regdfaexec(Dfa *dp, Exec *xp)
+{
+	const unsigned char *s;
+	int i, nst, st, mb_cur_max;
+	w_type wc;
+
+	dp->flags = xp->flags & REG_NOTEOL;	/* for regtrans() */
+	mb_cur_max = xp->mb_cur_max;
+	if (xp->nmatch != 0)
+		return leftmost(dp, xp);
+	if (mb_cur_max == 1 && (xp->flags & REG_NEWLINE) == 0)
+		return regdfaexec_opt(dp, xp);
+	s = xp->str;
+	st = dp->anybol;
+	if (xp->flags & REG_NOTBOL)
+		st = 1;
+	if (dp->acc[st] && (xp->flags & REG_NONEMPTY) == 0)
+		return 0;	/* initial empty match allowed */
+	for (;;)
+	{
+		if ((wc = *s++) == '\n')
+		{
+			if (xp->flags & REG_NEWLINE)
+				wc = ROP_EOL;
+		}
+		else if (!ISONEBYTE(wc) && (i = libuxre_mb2wc(&wc, s)) > 0)
+			s += i;
+		if ((wc & ~(long)(NCHAR - 1)) != 0
+			|| (nst = dp->trans[st][wc]) == 0)
+		{
+			if ((nst=regtrans(dp, st, wc, mb_cur_max)) == 0)
+				return REG_ESPACE;
+			if (wc == ROP_EOL) /* REG_NEWLINE only */
+			{
+				if (dp->acc[nst - 1])
+					return 0;
+				if (dp->acc[st = dp->anybol])
+					return 0;
+				continue;
+			}
+		}
+		if (dp->acc[st = nst - 1])
+			return 0;
+		if (wc == '\0')	/* st == 0 */
+			return REG_NOMATCH;
+	}
+}