diff --git a/src/include/regex/cclass.h b/src/include/regex/cclass.h
new file mode 100644
index 0000000000000000000000000000000000000000..cabe7faf223ec2565c157cb934a265634d5b9864
--- /dev/null
+++ b/src/include/regex/cclass.h
@@ -0,0 +1,70 @@
+/*-
+ * Copyright (c) 1992, 1993, 1994 Henry Spencer.
+ * Copyright (c) 1992, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Henry Spencer.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)cclass.h	8.3 (Berkeley) 3/20/94
+ */
+
+/* character-class table */
+static struct cclass {
+	char *name;
+	char *chars;
+	char *multis;
+} cclasses[] = {
+	{"alnum",	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
+0123456789",				""},
+	{"alpha",	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz",
+					""},
+	{"blank",	" \t",		""},
+	{"cntrl",	"\007\b\t\n\v\f\r\1\2\3\4\5\6\16\17\20\21\22\23\24\
+\25\26\27\30\31\32\33\34\35\36\37\177",	""},
+	{"digit",	"0123456789",	""},
+	{"graph",	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
+0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
+					""},
+	{"lower",	"abcdefghijklmnopqrstuvwxyz",
+					""},
+	{"print",	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\
+0123456789!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~ ",
+					""},
+	{"punct",	"!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
+					""},
+	{"space",	"\t\n\v\f\r ",	""},
+	{"upper",	"ABCDEFGHIJKLMNOPQRSTUVWXYZ",
+					""},
+	{"xdigit",	"0123456789ABCDEFabcdef",
+					""},
+	{NULL,		0,		""}
+};
diff --git a/src/include/regex/cdefs.h b/src/include/regex/cdefs.h
new file mode 100644
index 0000000000000000000000000000000000000000..cdca2af164d545a5d8e640f515ecac312719cb0e
--- /dev/null
+++ b/src/include/regex/cdefs.h
@@ -0,0 +1,144 @@
+/*
+ * ++Copyright++ 1991, 1993
+ * -
+ * Copyright (c) 1991, 1993
+ *    The Regents of the University of California.  All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ * 	This product includes software developed by the University of
+ * 	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * -
+ * Portions Copyright (c) 1993 by Digital Equipment Corporation.
+ * 
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies, and that
+ * the name of Digital Equipment Corporation not be used in advertising or
+ * publicity pertaining to distribution of the document or software without
+ * specific, written prior permission.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
+ * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ * -
+ * --Copyright--
+ */
+
+/*
+ *	@(#)cdefs.h	8.1 (Berkeley) 6/2/93
+ *	$Id: cdefs.h,v 1.1 1996/09/20 05:29:23 scrappy Exp $
+ */
+
+#ifndef	_CDEFS_H_
+#define	_CDEFS_H_
+
+#if defined(__cplusplus)
+#define	__BEGIN_DECLS	extern "C" {
+#define	__END_DECLS	};
+#else
+#define	__BEGIN_DECLS
+#define	__END_DECLS
+#endif
+
+/*
+ * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
+ * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
+ * The __CONCAT macro is a bit tricky -- make sure you don't put spaces
+ * in between its arguments.  __CONCAT can also concatenate double-quoted
+ * strings produced by the __STRING macro, but this only works with ANSI C.
+ */
+#if defined(__STDC__) || defined(__cplusplus)
+#define	__P(protos)	protos		/* full-blown ANSI C */
+#define	__CONCAT(x,y)	x ## y
+#define	__STRING(x)	#x
+
+#define	__const		const		/* define reserved names to standard */
+#define	__signed	signed
+#define	__volatile	volatile
+#if defined(__cplusplus)
+#define	__inline	inline		/* convert to C++ keyword */
+#else
+#ifndef __GNUC__
+#define	__inline			/* delete GCC keyword */
+#endif /* !__GNUC__ */
+#endif /* !__cplusplus */
+
+#else	/* !(__STDC__ || __cplusplus) */
+#define	__P(protos)	()		/* traditional C preprocessor */
+#define	__CONCAT(x,y)	x/**/y
+#define	__STRING(x)	"x"
+
+#ifndef __GNUC__
+#define	__const				/* delete pseudo-ANSI C keywords */
+#define	__inline
+#define	__signed
+#define	__volatile
+/*
+ * In non-ANSI C environments, new programs will want ANSI-only C keywords
+ * deleted from the program and old programs will want them left alone.
+ * When using a compiler other than gcc, programs using the ANSI C keywords
+ * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
+ * When using "gcc -traditional", we assume that this is the intent; if
+ * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
+ */
+#ifndef	NO_ANSI_KEYWORDS
+#define	const				/* delete ANSI C keywords */
+#define	inline
+#define	signed
+#define	volatile
+#endif
+#endif	/* !__GNUC__ */
+#endif	/* !(__STDC__ || __cplusplus) */
+
+/*
+ * GCC1 and some versions of GCC2 declare dead (non-returning) and
+ * pure (no side effects) functions using "volatile" and "const";
+ * unfortunately, these then cause warnings under "-ansi -pedantic".
+ * GCC2 uses a new, peculiar __attribute__((attrs)) style.  All of
+ * these work for GNU C++ (modulo a slight glitch in the C++ grammar
+ * in the distribution version of 2.5.5).
+ */
+#if !defined(__GNUC__) || __GNUC__ < 2 || __GNUC_MINOR__ < 5
+#define	__attribute__(x)	/* delete __attribute__ if non-gcc or gcc1 */
+#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
+#define	__dead		__volatile
+#define	__pure		__const
+#endif
+#endif
+
+/* Delete pseudo-keywords wherever they are not available or needed. */
+#ifndef __dead
+#define	__dead
+#define	__pure
+#endif
+
+#endif /* !_CDEFS_H_ */
diff --git a/src/include/regex/cname.h b/src/include/regex/cname.h
new file mode 100644
index 0000000000000000000000000000000000000000..c6ba15bdc367b76c6392cfc342c9e83f7eb6776f
--- /dev/null
+++ b/src/include/regex/cname.h
@@ -0,0 +1,141 @@
+/*-
+ * Copyright (c) 1992, 1993, 1994 Henry Spencer.
+ * Copyright (c) 1992, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Henry Spencer.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)cname.h	8.3 (Berkeley) 3/20/94
+ */
+
+/* character-name table */
+static struct cname {
+	char *name;
+	char code;
+} cnames[] = {
+	{"NUL",	'\0'},
+	{"SOH",	'\001'},
+	{"STX",	'\002'},
+	{"ETX",	'\003'},
+	{"EOT",	'\004'},
+	{"ENQ",	'\005'},
+	{"ACK",	'\006'},
+	{"BEL",	'\007'},
+	{"alert",	'\007'},
+	{"BS",		'\010'},
+	{"backspace",	'\b'},
+	{"HT",		'\011'},
+	{"tab",		'\t'},
+	{"LF",		'\012'},
+	{"newline",	'\n'},
+	{"VT",		'\013'},
+	{"vertical-tab",	'\v'},
+	{"FF",		'\014'},
+	{"form-feed",	'\f'},
+	{"CR",		'\015'},
+	{"carriage-return",	'\r'},
+	{"SO",	'\016'},
+	{"SI",	'\017'},
+	{"DLE",	'\020'},
+	{"DC1",	'\021'},
+	{"DC2",	'\022'},
+	{"DC3",	'\023'},
+	{"DC4",	'\024'},
+	{"NAK",	'\025'},
+	{"SYN",	'\026'},
+	{"ETB",	'\027'},
+	{"CAN",	'\030'},
+	{"EM",	'\031'},
+	{"SUB",	'\032'},
+	{"ESC",	'\033'},
+	{"IS4",	'\034'},
+	{"FS",	'\034'},
+	{"IS3",	'\035'},
+	{"GS",	'\035'},
+	{"IS2",	'\036'},
+	{"RS",	'\036'},
+	{"IS1",	'\037'},
+	{"US",	'\037'},
+	{"space",		' '},
+	{"exclamation-mark",	'!'},
+	{"quotation-mark",	'"'},
+	{"number-sign",		'#'},
+	{"dollar-sign",		'$'},
+	{"percent-sign",		'%'},
+	{"ampersand",		'&'},
+	{"apostrophe",		'\''},
+	{"left-parenthesis",	'('},
+	{"right-parenthesis",	')'},
+	{"asterisk",	'*'},
+	{"plus-sign",	'+'},
+	{"comma",	','},
+	{"hyphen",	'-'},
+	{"hyphen-minus",	'-'},
+	{"period",	'.'},
+	{"full-stop",	'.'},
+	{"slash",	'/'},
+	{"solidus",	'/'},
+	{"zero",		'0'},
+	{"one",		'1'},
+	{"two",		'2'},
+	{"three",	'3'},
+	{"four",		'4'},
+	{"five",		'5'},
+	{"six",		'6'},
+	{"seven",	'7'},
+	{"eight",	'8'},
+	{"nine",		'9'},
+	{"colon",	':'},
+	{"semicolon",	';'},
+	{"less-than-sign",	'<'},
+	{"equals-sign",		'='},
+	{"greater-than-sign",	'>'},
+	{"question-mark",	'?'},
+	{"commercial-at",	'@'},
+	{"left-square-bracket",	'['},
+	{"backslash",		'\\'},
+	{"reverse-solidus",	'\\'},
+	{"right-square-bracket",	']'},
+	{"circumflex",		'^'},
+	{"circumflex-accent",	'^'},
+	{"underscore",		'_'},
+	{"low-line",		'_'},
+	{"grave-accent",		'`'},
+	{"left-brace",		'{'},
+	{"left-curly-bracket",	'{'},
+	{"vertical-line",	'|'},
+	{"right-brace",		'}'},
+	{"right-curly-bracket",	'}'},
+	{"tilde",		'~'},
+	{"DEL",	'\177'},
+	{NULL,	0}
+};
diff --git a/src/include/regex/regex.h b/src/include/regex/regex.h
new file mode 100644
index 0000000000000000000000000000000000000000..fd5484f13fb96eca5470c45ed5db416419806567
--- /dev/null
+++ b/src/include/regex/regex.h
@@ -0,0 +1,108 @@
+/*-
+ * Copyright (c) 1992 Henry Spencer.
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Henry Spencer of the University of Toronto.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)regex.h	8.2 (Berkeley) 1/3/94
+ */
+
+#ifndef _REGEX_H_
+#define	_REGEX_H_
+
+/* #include <sys/cdefs.h> */
+/* since not all systems have cdefs.h, we'll use our own here - jolly */
+#include "cdefs.h"
+
+/* types */
+typedef off_t regoff_t;
+
+typedef struct {
+	int re_magic;
+	size_t re_nsub;		/* number of parenthesized subexpressions */
+	__const char *re_endp;	/* end pointer for REG_PEND */
+	struct re_guts *re_g;	/* none of your business :-) */
+} regex_t;
+
+typedef struct {
+	regoff_t rm_so;		/* start of match */
+	regoff_t rm_eo;		/* end of match */
+} regmatch_t;
+
+/* regcomp() flags */
+#define	REG_BASIC	0000
+#define	REG_EXTENDED	0001
+#define	REG_ICASE	0002
+#define	REG_NOSUB	0004
+#define	REG_NEWLINE	0010
+#define	REG_NOSPEC	0020
+#define	REG_PEND	0040
+#define	REG_DUMP	0200
+
+/* regerror() flags */
+#define	REG_NOMATCH	 1
+#define	REG_BADPAT	 2
+#define	REG_ECOLLATE	 3
+#define	REG_ECTYPE	 4
+#define	REG_EESCAPE	 5
+#define	REG_ESUBREG	 6
+#define	REG_EBRACK	 7
+#define	REG_EPAREN	 8
+#define	REG_EBRACE	 9
+#define	REG_BADBR	10
+#define	REG_ERANGE	11
+#define	REG_ESPACE	12
+#define	REG_BADRPT	13
+#define	REG_EMPTY	14
+#define	REG_ASSERT	15
+#define	REG_INVARG	16
+#define	REG_ATOI	255	/* convert name to number (!) */
+#define	REG_ITOA	0400	/* convert number to name (!) */
+
+/* regexec() flags */
+#define	REG_NOTBOL	00001
+#define	REG_NOTEOL	00002
+#define	REG_STARTEND	00004
+#define	REG_TRACE	00400	/* tracing of execution */
+#define	REG_LARGE	01000	/* force large representation */
+#define	REG_BACKR	02000	/* force use of backref code */
+
+__BEGIN_DECLS
+int	pg95_regcomp __P((regex_t *, const char *, int));
+size_t	pg95_regerror __P((int, const regex_t *, char *, size_t));
+int	pg95_regexec __P((const regex_t *,
+	    const char *, size_t, regmatch_t [], int));
+void	pg95_regfree __P((regex_t *));
+__END_DECLS
+
+#endif /* !_REGEX_H_ */
diff --git a/src/include/regex/regex2.h b/src/include/regex/regex2.h
new file mode 100644
index 0000000000000000000000000000000000000000..0261b535d02921077197ce5b2af40a08c5b6c54f
--- /dev/null
+++ b/src/include/regex/regex2.h
@@ -0,0 +1,175 @@
+/*-
+ * Copyright (c) 1992, 1993, 1994 Henry Spencer.
+ * Copyright (c) 1992, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Henry Spencer.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)regex2.h	8.4 (Berkeley) 3/20/94
+ */
+
+/*
+ * First, the stuff that ends up in the outside-world include file
+*/
+/*
+ typedef off_t regoff_t;
+ typedef struct {
+ 	int re_magic;
+ 	size_t re_nsub;		// number of parenthesized subexpressions
+ 	const char *re_endp;	// end pointer for REG_PEND
+ 	struct re_guts *re_g;	// none of your business :-)
+ } regex_t;
+ typedef struct {
+ 	regoff_t rm_so;		// start of match
+ 	regoff_t rm_eo;		// end of match
+ } regmatch_t;
+*/
+/*
+ * internals of regex_t
+ */
+#define	MAGIC1	((('r'^0200)<<8) | 'e')
+
+/*
+ * The internal representation is a *strip*, a sequence of
+ * operators ending with an endmarker.  (Some terminology etc. is a
+ * historical relic of earlier versions which used multiple strips.)
+ * Certain oddities in the representation are there to permit running
+ * the machinery backwards; in particular, any deviation from sequential
+ * flow must be marked at both its source and its destination.  Some
+ * fine points:
+ *
+ * - OPLUS_ and O_PLUS are *inside* the loop they create.
+ * - OQUEST_ and O_QUEST are *outside* the bypass they create.
+ * - OCH_ and O_CH are *outside* the multi-way branch they create, while
+ *   OOR1 and OOR2 are respectively the end and the beginning of one of
+ *   the branches.  Note that there is an implicit OOR2 following OCH_
+ *   and an implicit OOR1 preceding O_CH.
+ *
+ * In state representations, an operator's bit is on to signify a state
+ * immediately *preceding* "execution" of that operator.
+ */
+typedef unsigned long sop;	/* strip operator */
+typedef long sopno;
+#define	OPRMASK	0xf8000000
+#define	OPDMASK	0x07ffffff
+#define	OPSHIFT	((unsigned)27)
+#define	OP(n)	((n)&OPRMASK)
+#define	OPND(n)	((n)&OPDMASK)
+#define	SOP(op, opnd)	((op)|(opnd))
+/* operators			   meaning	operand			*/
+/*						(back, fwd are offsets)	*/
+#define	OEND	(1<<OPSHIFT)	/* endmarker	-			*/
+#define	OCHAR	(2<<OPSHIFT)	/* character	unsigned char		*/
+#define	OBOL	(3<<OPSHIFT)	/* left anchor	-			*/
+#define	OEOL	(4<<OPSHIFT)	/* right anchor	-			*/
+#define	OANY	(5<<OPSHIFT)	/* .		-			*/
+#define	OANYOF	(6<<OPSHIFT)	/* [...]	set number		*/
+#define	OBACK_	(7<<OPSHIFT)	/* begin \d	paren number		*/
+#define	O_BACK	(8<<OPSHIFT)	/* end \d	paren number		*/
+#define	OPLUS_	(9<<OPSHIFT)	/* + prefix	fwd to suffix		*/
+#define	O_PLUS	(10<<OPSHIFT)	/* + suffix	back to prefix		*/
+#define	OQUEST_	(11<<OPSHIFT)	/* ? prefix	fwd to suffix		*/
+#define	O_QUEST	(12<<OPSHIFT)	/* ? suffix	back to prefix		*/
+#define	OLPAREN	(13<<OPSHIFT)	/* (		fwd to )		*/
+#define	ORPAREN	(14<<OPSHIFT)	/* )		back to (		*/
+#define	OCH_	(15<<OPSHIFT)	/* begin choice	fwd to OOR2		*/
+#define	OOR1	(16<<OPSHIFT)	/* | pt. 1	back to OOR1 or OCH_	*/
+#define	OOR2	(17<<OPSHIFT)	/* | pt. 2	fwd to OOR2 or O_CH	*/
+#define	O_CH	(18<<OPSHIFT)	/* end choice	back to OOR1		*/
+#define	OBOW	(19<<OPSHIFT)	/* begin word	-			*/
+#define	OEOW	(20<<OPSHIFT)	/* end word	-			*/
+
+/*
+ * Structure for [] character-set representation.  Character sets are
+ * done as bit vectors, grouped 8 to a byte vector for compactness.
+ * The individual set therefore has both a pointer to the byte vector
+ * and a mask to pick out the relevant bit of each byte.  A hash code
+ * simplifies testing whether two sets could be identical.
+ *
+ * This will get trickier for multicharacter collating elements.  As
+ * preliminary hooks for dealing with such things, we also carry along
+ * a string of multi-character elements, and decide the size of the
+ * vectors at run time.
+ */
+typedef struct {
+	uch *ptr;		/* -> uch [csetsize] */
+	uch mask;		/* bit within array */
+	uch hash;		/* hash code */
+	size_t smultis;
+	char *multis;		/* -> char[smulti]  ab\0cd\0ef\0\0 */
+} cset;
+/* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */
+#define	CHadd(cs, c)	((cs)->ptr[(uch)(c)] |= (cs)->mask, (cs)->hash += (c))
+#define	CHsub(cs, c)	((cs)->ptr[(uch)(c)] &= ~(cs)->mask, (cs)->hash -= (c))
+#define	CHIN(cs, c)	((cs)->ptr[(uch)(c)] & (cs)->mask)
+#define	MCadd(p, cs, cp)	mcadd(p, cs, cp)	/* regcomp() internal fns */
+#define	MCsub(p, cs, cp)	mcsub(p, cs, cp)
+#define	MCin(p, cs, cp)	mcin(p, cs, cp)
+
+/* stuff for character categories */
+typedef unsigned char cat_t;
+
+/*
+ * main compiled-expression structure
+ */
+struct re_guts {
+	int magic;
+#		define	MAGIC2	((('R'^0200)<<8)|'E')
+	sop *strip;		/* malloced area for strip */
+	int csetsize;		/* number of bits in a cset vector */
+	int ncsets;		/* number of csets in use */
+	cset *sets;		/* -> cset [ncsets] */
+	uch *setbits;		/* -> uch[csetsize][ncsets/CHAR_BIT] */
+	int cflags;		/* copy of regcomp() cflags argument */
+	sopno nstates;		/* = number of sops */
+	sopno firststate;	/* the initial OEND (normally 0) */
+	sopno laststate;	/* the final OEND */
+	int iflags;		/* internal flags */
+#		define	USEBOL	01	/* used ^ */
+#		define	USEEOL	02	/* used $ */
+#		define	BAD	04	/* something wrong */
+	int nbol;		/* number of ^ used */
+	int neol;		/* number of $ used */
+	int ncategories;	/* how many character categories */
+	cat_t *categories;	/* ->catspace[-CHAR_MIN] */
+	char *must;		/* match must contain this string */
+	int mlen;		/* length of must */
+	size_t nsub;		/* copy of re_nsub */
+	int backrefs;		/* does it use back references? */
+	sopno nplus;		/* how deep does it nest +s? */
+	/* catspace must be last */
+	cat_t catspace[1];	/* actually [NC] */
+};
+
+/* misc utilities */
+#define	OUT	(CHAR_MAX+1)	/* a non-character value */
+#define	ISWORD(c)	(isalnum(c) || (c) == '_')
diff --git a/src/include/regex/regexp.h b/src/include/regex/regexp.h
new file mode 100644
index 0000000000000000000000000000000000000000..bf39dab693ca46f24502718d0facab0056a27b9f
--- /dev/null
+++ b/src/include/regex/regexp.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 1986 by University of Toronto.
+ * Copyright (c) 1989, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley
+ * by Henry Spencer.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)regexp.h	8.1 (Berkeley) 6/2/93
+ */
+
+#ifndef	_REGEXP_H_
+#define	_REGEXP_H_
+
+/*
+ * Definitions etc. for regexp(3) routines.
+ *
+ * Caveat:  this is V8 regexp(3) [actually, a reimplementation thereof],
+ * not the System V one.
+ */
+#define NSUBEXP  10
+typedef struct regexp {
+	char *startp[NSUBEXP];
+	char *endp[NSUBEXP];
+	char regstart;		/* Internal use only. */
+	char reganch;		/* Internal use only. */
+	char *regmust;		/* Internal use only. */
+	int regmlen;		/* Internal use only. */
+	char program[1];	/* Unwarranted chumminess with compiler. */
+} regexp;
+
+/* #include <sys/cdefs.h> */
+/* since not all systems have cdefs.h, we'll use our own here - jolly */
+#include "cdefs.h"
+
+__BEGIN_DECLS
+regexp *pg95_regcomp __P((const char *));
+int pg95_regexec __P((const  regexp *, const char *));
+void pg95_regsub __P((const  regexp *, const char *, char *));
+void pg95_regerror __P((const char *));
+__END_DECLS
+
+#endif /* !_REGEXP_H_ */
diff --git a/src/include/regex/utils.h b/src/include/regex/utils.h
new file mode 100644
index 0000000000000000000000000000000000000000..cbab44259e0703849630675ebf186c96e3a38f8d
--- /dev/null
+++ b/src/include/regex/utils.h
@@ -0,0 +1,57 @@
+/*-
+ * Copyright (c) 1992, 1993, 1994 Henry Spencer.
+ * Copyright (c) 1992, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Henry Spencer.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)utils.h	8.3 (Berkeley) 3/20/94
+ */
+
+/* utility definitions */
+#define	DUPMAX		100000000	/* xxx is this right? */
+#define	INFINITY	(DUPMAX + 1)
+#define	NC		(CHAR_MAX - CHAR_MIN + 1)
+typedef unsigned char uch;
+
+/* switch off assertions (if not already off) if no REDEBUG */
+#ifndef REDEBUG
+#ifndef NDEBUG
+#define	NDEBUG	/* no assertions please */
+#endif
+#endif
+#include <assert.h>
+
+/* for old systems with bcopy() but no memmove() */
+#if defined(PORTNAME_sparc)
+#define	memmove(d, s, c)	bcopy(s, d, c)
+#endif